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linux/net/core/filter.c

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/*
* Linux Socket Filter - Kernel level socket filtering
*
* Based on the design of the Berkeley Packet Filter. The new
* internal format has been designed by PLUMgrid:
*
* Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
*
* Authors:
*
* Jay Schulist <jschlst@samba.org>
* Alexei Starovoitov <ast@plumgrid.com>
* Daniel Borkmann <dborkman@redhat.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Andi Kleen - Fix a few bad bugs and races.
* Kris Katterjohn - Added many additional checks in bpf_check_classic()
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/sock_diag.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_packet.h>
#include <linux/if_arp.h>
#include <linux/gfp.h>
#include <net/inet_common.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <net/netlink.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/flow_dissector.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <linux/uaccess.h>
#include <asm/unaligned.h>
#include <asm/cmpxchg.h>
#include <linux/filter.h>
#include <linux/ratelimit.h>
#include <linux/seccomp.h>
#include <linux/if_vlan.h>
#include <linux/bpf.h>
#include <net/sch_generic.h>
#include <net/cls_cgroup.h>
#include <net/dst_metadata.h>
#include <net/dst.h>
#include <net/sock_reuseport.h>
#include <net/busy_poll.h>
#include <net/tcp.h>
#include <net/xfrm.h>
#include <linux/bpf_trace.h>
#include <net/xdp_sock.h>
#include <linux/inetdevice.h>
#include <net/ip_fib.h>
#include <net/flow.h>
#include <net/arp.h>
#include <net/ipv6.h>
#include <linux/seg6_local.h>
#include <net/seg6.h>
#include <net/seg6_local.h>
/**
* sk_filter_trim_cap - run a packet through a socket filter
* @sk: sock associated with &sk_buff
* @skb: buffer to filter
* @cap: limit on how short the eBPF program may trim the packet
*
* Run the eBPF program and then cut skb->data to correct size returned by
* the program. If pkt_len is 0 we toss packet. If skb->len is smaller
* than pkt_len we keep whole skb->data. This is the socket level
* wrapper to BPF_PROG_RUN. It returns 0 if the packet should
* be accepted or -EPERM if the packet should be tossed.
*
*/
int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
{
int err;
struct sk_filter *filter;
/*
* If the skb was allocated from pfmemalloc reserves, only
* allow SOCK_MEMALLOC sockets to use it as this socket is
* helping free memory
*/
if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) {
NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP);
return -ENOMEM;
}
err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb);
if (err)
return err;
err = security_sock_rcv_skb(sk, skb);
if (err)
return err;
rcu_read_lock();
filter = rcu_dereference(sk->sk_filter);
if (filter) {
struct sock *save_sk = skb->sk;
unsigned int pkt_len;
skb->sk = sk;
pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
skb->sk = save_sk;
err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
}
rcu_read_unlock();
return err;
}
EXPORT_SYMBOL(sk_filter_trim_cap);
BPF_CALL_1(bpf_skb_get_pay_offset, struct sk_buff *, skb)
{
return skb_get_poff(skb);
}
BPF_CALL_3(bpf_skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x)
{
struct nlattr *nla;
if (skb_is_nonlinear(skb))
return 0;
if (skb->len < sizeof(struct nlattr))
return 0;
if (a > skb->len - sizeof(struct nlattr))
return 0;
nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x);
if (nla)
return (void *) nla - (void *) skb->data;
return 0;
}
BPF_CALL_3(bpf_skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x)
{
struct nlattr *nla;
if (skb_is_nonlinear(skb))
return 0;
if (skb->len < sizeof(struct nlattr))
return 0;
if (a > skb->len - sizeof(struct nlattr))
return 0;
nla = (struct nlattr *) &skb->data[a];
if (nla->nla_len > skb->len - a)
return 0;
nla = nla_find_nested(nla, x);
if (nla)
return (void *) nla - (void *) skb->data;
return 0;
}
BPF_CALL_4(bpf_skb_load_helper_8, const struct sk_buff *, skb, const void *,
data, int, headlen, int, offset)
{
u8 tmp, *ptr;
const int len = sizeof(tmp);
if (offset >= 0) {
if (headlen - offset >= len)
return *(u8 *)(data + offset);
if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
return tmp;
} else {
ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
if (likely(ptr))
return *(u8 *)ptr;
}
return -EFAULT;
}
BPF_CALL_2(bpf_skb_load_helper_8_no_cache, const struct sk_buff *, skb,
int, offset)
{
return ____bpf_skb_load_helper_8(skb, skb->data, skb->len - skb->data_len,
offset);
}
BPF_CALL_4(bpf_skb_load_helper_16, const struct sk_buff *, skb, const void *,
data, int, headlen, int, offset)
{
u16 tmp, *ptr;
const int len = sizeof(tmp);
if (offset >= 0) {
if (headlen - offset >= len)
return get_unaligned_be16(data + offset);
if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
return be16_to_cpu(tmp);
} else {
ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
if (likely(ptr))
return get_unaligned_be16(ptr);
}
return -EFAULT;
}
BPF_CALL_2(bpf_skb_load_helper_16_no_cache, const struct sk_buff *, skb,
int, offset)
{
return ____bpf_skb_load_helper_16(skb, skb->data, skb->len - skb->data_len,
offset);
}
BPF_CALL_4(bpf_skb_load_helper_32, const struct sk_buff *, skb, const void *,
data, int, headlen, int, offset)
{
u32 tmp, *ptr;
const int len = sizeof(tmp);
if (likely(offset >= 0)) {
if (headlen - offset >= len)
return get_unaligned_be32(data + offset);
if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
return be32_to_cpu(tmp);
} else {
ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
if (likely(ptr))
return get_unaligned_be32(ptr);
}
return -EFAULT;
}
BPF_CALL_2(bpf_skb_load_helper_32_no_cache, const struct sk_buff *, skb,
int, offset)
{
return ____bpf_skb_load_helper_32(skb, skb->data, skb->len - skb->data_len,
offset);
}
BPF_CALL_0(bpf_get_raw_cpu_id)
{
return raw_smp_processor_id();
}
static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = {
.func = bpf_get_raw_cpu_id,
.gpl_only = false,
.ret_type = RET_INTEGER,
};
static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
struct bpf_insn *insn_buf)
{
struct bpf_insn *insn = insn_buf;
switch (skb_field) {
case SKF_AD_MARK:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4);
*insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
offsetof(struct sk_buff, mark));
break;
case SKF_AD_PKTTYPE:
*insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET());
*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
#ifdef __BIG_ENDIAN_BITFIELD
*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
#endif
break;
case SKF_AD_QUEUE:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, queue_mapping) != 2);
*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
offsetof(struct sk_buff, queue_mapping));
break;
case SKF_AD_VLAN_TAG:
case SKF_AD_VLAN_TAG_PRESENT:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
/* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
offsetof(struct sk_buff, vlan_tci));
if (skb_field == SKF_AD_VLAN_TAG) {
*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg,
~VLAN_TAG_PRESENT);
} else {
/* dst_reg >>= 12 */
*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 12);
/* dst_reg &= 1 */
*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1);
}
break;
}
return insn - insn_buf;
}
static bool convert_bpf_extensions(struct sock_filter *fp,
struct bpf_insn **insnp)
{
struct bpf_insn *insn = *insnp;
u32 cnt;
switch (fp->k) {
case SKF_AD_OFF + SKF_AD_PROTOCOL:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2);
/* A = *(u16 *) (CTX + offsetof(protocol)) */
*insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
offsetof(struct sk_buff, protocol));
/* A = ntohs(A) [emitting a nop or swap16] */
*insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
break;
case SKF_AD_OFF + SKF_AD_PKTTYPE:
cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
insn += cnt - 1;
break;
case SKF_AD_OFF + SKF_AD_IFINDEX:
case SKF_AD_OFF + SKF_AD_HATYPE:
BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4);
BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, type) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
BPF_REG_TMP, BPF_REG_CTX,
offsetof(struct sk_buff, dev));
/* if (tmp != 0) goto pc + 1 */
*insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
*insn++ = BPF_EXIT_INSN();
if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
offsetof(struct net_device, ifindex));
else
*insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
offsetof(struct net_device, type));
break;
case SKF_AD_OFF + SKF_AD_MARK:
cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
insn += cnt - 1;
break;
case SKF_AD_OFF + SKF_AD_RXHASH:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4);
*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
offsetof(struct sk_buff, hash));
break;
case SKF_AD_OFF + SKF_AD_QUEUE:
cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
insn += cnt - 1;
break;
case SKF_AD_OFF + SKF_AD_VLAN_TAG:
cnt = convert_skb_access(SKF_AD_VLAN_TAG,
BPF_REG_A, BPF_REG_CTX, insn);
insn += cnt - 1;
break;
case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
BPF_REG_A, BPF_REG_CTX, insn);
insn += cnt - 1;
break;
case SKF_AD_OFF + SKF_AD_VLAN_TPID:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_proto) != 2);
/* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
*insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
offsetof(struct sk_buff, vlan_proto));
/* A = ntohs(A) [emitting a nop or swap16] */
*insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
break;
case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
case SKF_AD_OFF + SKF_AD_NLATTR:
case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
case SKF_AD_OFF + SKF_AD_CPU:
case SKF_AD_OFF + SKF_AD_RANDOM:
/* arg1 = CTX */
*insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
/* arg2 = A */
*insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
/* arg3 = X */
*insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
/* Emit call(arg1=CTX, arg2=A, arg3=X) */
switch (fp->k) {
case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
*insn = BPF_EMIT_CALL(bpf_skb_get_pay_offset);
break;
case SKF_AD_OFF + SKF_AD_NLATTR:
*insn = BPF_EMIT_CALL(bpf_skb_get_nlattr);
break;
case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
*insn = BPF_EMIT_CALL(bpf_skb_get_nlattr_nest);
break;
case SKF_AD_OFF + SKF_AD_CPU:
*insn = BPF_EMIT_CALL(bpf_get_raw_cpu_id);
break;
case SKF_AD_OFF + SKF_AD_RANDOM:
*insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
bpf_user_rnd_init_once();
break;
}
break;
case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
/* A ^= X */
*insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
break;
default:
/* This is just a dummy call to avoid letting the compiler
* evict __bpf_call_base() as an optimization. Placed here
* where no-one bothers.
*/
BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
return false;
}
*insnp = insn;
return true;
}
static bool convert_bpf_ld_abs(struct sock_filter *fp, struct bpf_insn **insnp)
{
const bool unaligned_ok = IS_BUILTIN(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS);
int size = bpf_size_to_bytes(BPF_SIZE(fp->code));
bool endian = BPF_SIZE(fp->code) == BPF_H ||
BPF_SIZE(fp->code) == BPF_W;
bool indirect = BPF_MODE(fp->code) == BPF_IND;
const int ip_align = NET_IP_ALIGN;
struct bpf_insn *insn = *insnp;
int offset = fp->k;
if (!indirect &&
((unaligned_ok && offset >= 0) ||
(!unaligned_ok && offset >= 0 &&
offset + ip_align >= 0 &&
offset + ip_align % size == 0))) {
bool ldx_off_ok = offset <= S16_MAX;
*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_H);
*insn++ = BPF_ALU64_IMM(BPF_SUB, BPF_REG_TMP, offset);
*insn++ = BPF_JMP_IMM(BPF_JSLT, BPF_REG_TMP,
size, 2 + endian + (!ldx_off_ok * 2));
if (ldx_off_ok) {
*insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
BPF_REG_D, offset);
} else {
*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_D);
*insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_TMP, offset);
*insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
BPF_REG_TMP, 0);
}
if (endian)
*insn++ = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, size * 8);
*insn++ = BPF_JMP_A(8);
}
*insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
*insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_D);
*insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_H);
if (!indirect) {
*insn++ = BPF_MOV64_IMM(BPF_REG_ARG4, offset);
} else {
*insn++ = BPF_MOV64_REG(BPF_REG_ARG4, BPF_REG_X);
if (fp->k)
*insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG4, offset);
}
switch (BPF_SIZE(fp->code)) {
case BPF_B:
*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8);
break;
case BPF_H:
*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16);
break;
case BPF_W:
*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32);
break;
default:
return false;
}
*insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_A, 0, 2);
*insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
*insn = BPF_EXIT_INSN();
*insnp = insn;
return true;
}
/**
* bpf_convert_filter - convert filter program
* @prog: the user passed filter program
* @len: the length of the user passed filter program
* @new_prog: allocated 'struct bpf_prog' or NULL
* @new_len: pointer to store length of converted program
* @seen_ld_abs: bool whether we've seen ld_abs/ind
*
* Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
* style extended BPF (eBPF).
* Conversion workflow:
*
* 1) First pass for calculating the new program length:
* bpf_convert_filter(old_prog, old_len, NULL, &new_len, &seen_ld_abs)
*
* 2) 2nd pass to remap in two passes: 1st pass finds new
* jump offsets, 2nd pass remapping:
* bpf_convert_filter(old_prog, old_len, new_prog, &new_len, &seen_ld_abs)
*/
static int bpf_convert_filter(struct sock_filter *prog, int len,
struct bpf_prog *new_prog, int *new_len,
bool *seen_ld_abs)
{
int new_flen = 0, pass = 0, target, i, stack_off;
struct bpf_insn *new_insn, *first_insn = NULL;
struct sock_filter *fp;
int *addrs = NULL;
u8 bpf_src;
BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
if (len <= 0 || len > BPF_MAXINSNS)
return -EINVAL;
if (new_prog) {
first_insn = new_prog->insnsi;
addrs = kcalloc(len, sizeof(*addrs),
GFP_KERNEL | __GFP_NOWARN);
if (!addrs)
return -ENOMEM;
}
do_pass:
new_insn = first_insn;
fp = prog;
/* Classic BPF related prologue emission. */
if (new_prog) {
/* Classic BPF expects A and X to be reset first. These need
* to be guaranteed to be the first two instructions.
*/
*new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
*new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);
/* All programs must keep CTX in callee saved BPF_REG_CTX.
* In eBPF case it's done by the compiler, here we need to
* do this ourself. Initial CTX is present in BPF_REG_ARG1.
*/
*new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
if (*seen_ld_abs) {
/* For packet access in classic BPF, cache skb->data
* in callee-saved BPF R8 and skb->len - skb->data_len
* (headlen) in BPF R9. Since classic BPF is read-only
* on CTX, we only need to cache it once.
*/
*new_insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
BPF_REG_D, BPF_REG_CTX,
offsetof(struct sk_buff, data));
*new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_H, BPF_REG_CTX,
offsetof(struct sk_buff, len));
*new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_TMP, BPF_REG_CTX,
offsetof(struct sk_buff, data_len));
*new_insn++ = BPF_ALU32_REG(BPF_SUB, BPF_REG_H, BPF_REG_TMP);
}
} else {
new_insn += 3;
}
for (i = 0; i < len; fp++, i++) {
struct bpf_insn tmp_insns[32] = { };
struct bpf_insn *insn = tmp_insns;
if (addrs)
addrs[i] = new_insn - first_insn;
switch (fp->code) {
/* All arithmetic insns and skb loads map as-is. */
case BPF_ALU | BPF_ADD | BPF_X:
case BPF_ALU | BPF_ADD | BPF_K:
case BPF_ALU | BPF_SUB | BPF_X:
case BPF_ALU | BPF_SUB | BPF_K:
case BPF_ALU | BPF_AND | BPF_X:
case BPF_ALU | BPF_AND | BPF_K:
case BPF_ALU | BPF_OR | BPF_X:
case BPF_ALU | BPF_OR | BPF_K:
case BPF_ALU | BPF_LSH | BPF_X:
case BPF_ALU | BPF_LSH | BPF_K:
case BPF_ALU | BPF_RSH | BPF_X:
case BPF_ALU | BPF_RSH | BPF_K:
case BPF_ALU | BPF_XOR | BPF_X:
case BPF_ALU | BPF_XOR | BPF_K:
case BPF_ALU | BPF_MUL | BPF_X:
case BPF_ALU | BPF_MUL | BPF_K:
case BPF_ALU | BPF_DIV | BPF_X:
case BPF_ALU | BPF_DIV | BPF_K:
case BPF_ALU | BPF_MOD | BPF_X:
case BPF_ALU | BPF_MOD | BPF_K:
case BPF_ALU | BPF_NEG:
case BPF_LD | BPF_ABS | BPF_W:
case BPF_LD | BPF_ABS | BPF_H:
case BPF_LD | BPF_ABS | BPF_B:
case BPF_LD | BPF_IND | BPF_W:
case BPF_LD | BPF_IND | BPF_H:
case BPF_LD | BPF_IND | BPF_B:
/* Check for overloaded BPF extension and
* directly convert it if found, otherwise
* just move on with mapping.
*/
if (BPF_CLASS(fp->code) == BPF_LD &&
BPF_MODE(fp->code) == BPF_ABS &&
convert_bpf_extensions(fp, &insn))
break;
if (BPF_CLASS(fp->code) == BPF_LD &&
convert_bpf_ld_abs(fp, &insn)) {
*seen_ld_abs = true;
break;
}
if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) ||
fp->code == (BPF_ALU | BPF_MOD | BPF_X)) {
*insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X);
/* Error with exception code on div/mod by 0.
* For cBPF programs, this was always return 0.
*/
*insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_X, 0, 2);
*insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
*insn++ = BPF_EXIT_INSN();
}
*insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
break;
/* Jump transformation cannot use BPF block macros
* everywhere as offset calculation and target updates
* require a bit more work than the rest, i.e. jump
* opcodes map as-is, but offsets need adjustment.
*/
#define BPF_EMIT_JMP \
do { \
const s32 off_min = S16_MIN, off_max = S16_MAX; \
s32 off; \
\
if (target >= len || target < 0) \
goto err; \
off = addrs ? addrs[target] - addrs[i] - 1 : 0; \
/* Adjust pc relative offset for 2nd or 3rd insn. */ \
off -= insn - tmp_insns; \
/* Reject anything not fitting into insn->off. */ \
if (off < off_min || off > off_max) \
goto err; \
insn->off = off; \
} while (0)
case BPF_JMP | BPF_JA:
target = i + fp->k + 1;
insn->code = fp->code;
BPF_EMIT_JMP;
break;
case BPF_JMP | BPF_JEQ | BPF_K:
case BPF_JMP | BPF_JEQ | BPF_X:
case BPF_JMP | BPF_JSET | BPF_K:
case BPF_JMP | BPF_JSET | BPF_X:
case BPF_JMP | BPF_JGT | BPF_K:
case BPF_JMP | BPF_JGT | BPF_X:
case BPF_JMP | BPF_JGE | BPF_K:
case BPF_JMP | BPF_JGE | BPF_X:
if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
/* BPF immediates are signed, zero extend
* immediate into tmp register and use it
* in compare insn.
*/
*insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
insn->dst_reg = BPF_REG_A;
insn->src_reg = BPF_REG_TMP;
bpf_src = BPF_X;
} else {
insn->dst_reg = BPF_REG_A;
insn->imm = fp->k;
bpf_src = BPF_SRC(fp->code);
insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
}
/* Common case where 'jump_false' is next insn. */
if (fp->jf == 0) {
insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
target = i + fp->jt + 1;
BPF_EMIT_JMP;
break;
}
/* Convert some jumps when 'jump_true' is next insn. */
if (fp->jt == 0) {
switch (BPF_OP(fp->code)) {
case BPF_JEQ:
insn->code = BPF_JMP | BPF_JNE | bpf_src;
break;
case BPF_JGT:
insn->code = BPF_JMP | BPF_JLE | bpf_src;
break;
case BPF_JGE:
insn->code = BPF_JMP | BPF_JLT | bpf_src;
break;
default:
goto jmp_rest;
}
target = i + fp->jf + 1;
BPF_EMIT_JMP;
break;
}
jmp_rest:
/* Other jumps are mapped into two insns: Jxx and JA. */
target = i + fp->jt + 1;
insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
BPF_EMIT_JMP;
insn++;
insn->code = BPF_JMP | BPF_JA;
target = i + fp->jf + 1;
BPF_EMIT_JMP;
break;
/* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
case BPF_LDX | BPF_MSH | BPF_B: {
struct sock_filter tmp = {
.code = BPF_LD | BPF_ABS | BPF_B,
.k = fp->k,
};
*seen_ld_abs = true;
/* X = A */
*insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
/* A = BPF_R0 = *(u8 *) (skb->data + K) */
convert_bpf_ld_abs(&tmp, &insn);
insn++;
/* A &= 0xf */
*insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
/* A <<= 2 */
*insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
/* tmp = X */
*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_X);
/* X = A */
*insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
/* A = tmp */
*insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
break;
}
/* RET_K is remaped into 2 insns. RET_A case doesn't need an
* extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
*/
case BPF_RET | BPF_A:
case BPF_RET | BPF_K:
if (BPF_RVAL(fp->code) == BPF_K)
*insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
0, fp->k);
*insn = BPF_EXIT_INSN();
break;
/* Store to stack. */
case BPF_ST:
case BPF_STX:
stack_off = fp->k * 4 + 4;
*insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
BPF_ST ? BPF_REG_A : BPF_REG_X,
-stack_off);
/* check_load_and_stores() verifies that classic BPF can
* load from stack only after write, so tracking
* stack_depth for ST|STX insns is enough
*/
if (new_prog && new_prog->aux->stack_depth < stack_off)
new_prog->aux->stack_depth = stack_off;
break;
/* Load from stack. */
case BPF_LD | BPF_MEM:
case BPF_LDX | BPF_MEM:
stack_off = fp->k * 4 + 4;
*insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
BPF_REG_A : BPF_REG_X, BPF_REG_FP,
-stack_off);
break;
/* A = K or X = K */
case BPF_LD | BPF_IMM:
case BPF_LDX | BPF_IMM:
*insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
BPF_REG_A : BPF_REG_X, fp->k);
break;
/* X = A */
case BPF_MISC | BPF_TAX:
*insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
break;
/* A = X */
case BPF_MISC | BPF_TXA:
*insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
break;
/* A = skb->len or X = skb->len */
case BPF_LD | BPF_W | BPF_LEN:
case BPF_LDX | BPF_W | BPF_LEN:
*insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
offsetof(struct sk_buff, len));
break;
/* Access seccomp_data fields. */
case BPF_LDX | BPF_ABS | BPF_W:
/* A = *(u32 *) (ctx + K) */
*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
break;
/* Unknown instruction. */
default:
goto err;
}
insn++;
if (new_prog)
memcpy(new_insn, tmp_insns,
sizeof(*insn) * (insn - tmp_insns));
new_insn += insn - tmp_insns;
}
if (!new_prog) {
/* Only calculating new length. */
*new_len = new_insn - first_insn;
if (*seen_ld_abs)
*new_len += 4; /* Prologue bits. */
return 0;
}
pass++;
if (new_flen != new_insn - first_insn) {
new_flen = new_insn - first_insn;
if (pass > 2)
goto err;
goto do_pass;
}
kfree(addrs);
BUG_ON(*new_len != new_flen);
return 0;
err:
kfree(addrs);
return -EINVAL;
}
/* Security:
*
* As we dont want to clear mem[] array for each packet going through
* __bpf_prog_run(), we check that filter loaded by user never try to read
* a cell if not previously written, and we check all branches to be sure
* a malicious user doesn't try to abuse us.
*/
static int check_load_and_stores(const struct sock_filter *filter, int flen)
{
u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
int pc, ret = 0;
BUILD_BUG_ON(BPF_MEMWORDS > 16);
masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
if (!masks)
return -ENOMEM;
memset(masks, 0xff, flen * sizeof(*masks));
for (pc = 0; pc < flen; pc++) {
memvalid &= masks[pc];
switch (filter[pc].code) {
case BPF_ST:
case BPF_STX:
memvalid |= (1 << filter[pc].k);
break;
case BPF_LD | BPF_MEM:
case BPF_LDX | BPF_MEM:
if (!(memvalid & (1 << filter[pc].k))) {
ret = -EINVAL;
goto error;
}
break;
case BPF_JMP | BPF_JA:
/* A jump must set masks on target */
masks[pc + 1 + filter[pc].k] &= memvalid;
memvalid = ~0;
break;
case BPF_JMP | BPF_JEQ | BPF_K:
case BPF_JMP | BPF_JEQ | BPF_X:
case BPF_JMP | BPF_JGE | BPF_K:
case BPF_JMP | BPF_JGE | BPF_X:
case BPF_JMP | BPF_JGT | BPF_K:
case BPF_JMP | BPF_JGT | BPF_X:
case BPF_JMP | BPF_JSET | BPF_K:
case BPF_JMP | BPF_JSET | BPF_X:
/* A jump must set masks on targets */
masks[pc + 1 + filter[pc].jt] &= memvalid;
masks[pc + 1 + filter[pc].jf] &= memvalid;
memvalid = ~0;
break;
}
}
error:
kfree(masks);
return ret;
}
static bool chk_code_allowed(u16 code_to_probe)
{
static const bool codes[] = {
/* 32 bit ALU operations */
[BPF_ALU | BPF_ADD | BPF_K] = true,
[BPF_ALU | BPF_ADD | BPF_X] = true,
[BPF_ALU | BPF_SUB | BPF_K] = true,
[BPF_ALU | BPF_SUB | BPF_X] = true,
[BPF_ALU | BPF_MUL | BPF_K] = true,
[BPF_ALU | BPF_MUL | BPF_X] = true,
[BPF_ALU | BPF_DIV | BPF_K] = true,
[BPF_ALU | BPF_DIV | BPF_X] = true,
[BPF_ALU | BPF_MOD | BPF_K] = true,
[BPF_ALU | BPF_MOD | BPF_X] = true,
[BPF_ALU | BPF_AND | BPF_K] = true,
[BPF_ALU | BPF_AND | BPF_X] = true,
[BPF_ALU | BPF_OR | BPF_K] = true,
[BPF_ALU | BPF_OR | BPF_X] = true,
[BPF_ALU | BPF_XOR | BPF_K] = true,
[BPF_ALU | BPF_XOR | BPF_X] = true,
[BPF_ALU | BPF_LSH | BPF_K] = true,
[BPF_ALU | BPF_LSH | BPF_X] = true,
[BPF_ALU | BPF_RSH | BPF_K] = true,
[BPF_ALU | BPF_RSH | BPF_X] = true,
[BPF_ALU | BPF_NEG] = true,
/* Load instructions */
[BPF_LD | BPF_W | BPF_ABS] = true,
[BPF_LD | BPF_H | BPF_ABS] = true,
[BPF_LD | BPF_B | BPF_ABS] = true,
[BPF_LD | BPF_W | BPF_LEN] = true,
[BPF_LD | BPF_W | BPF_IND] = true,
[BPF_LD | BPF_H | BPF_IND] = true,
[BPF_LD | BPF_B | BPF_IND] = true,
[BPF_LD | BPF_IMM] = true,
[BPF_LD | BPF_MEM] = true,
[BPF_LDX | BPF_W | BPF_LEN] = true,
[BPF_LDX | BPF_B | BPF_MSH] = true,
[BPF_LDX | BPF_IMM] = true,
[BPF_LDX | BPF_MEM] = true,
/* Store instructions */
[BPF_ST] = true,
[BPF_STX] = true,
/* Misc instructions */
[BPF_MISC | BPF_TAX] = true,
[BPF_MISC | BPF_TXA] = true,
/* Return instructions */
[BPF_RET | BPF_K] = true,
[BPF_RET | BPF_A] = true,
/* Jump instructions */
[BPF_JMP | BPF_JA] = true,
[BPF_JMP | BPF_JEQ | BPF_K] = true,
[BPF_JMP | BPF_JEQ | BPF_X] = true,
[BPF_JMP | BPF_JGE | BPF_K] = true,
[BPF_JMP | BPF_JGE | BPF_X] = true,
[BPF_JMP | BPF_JGT | BPF_K] = true,
[BPF_JMP | BPF_JGT | BPF_X] = true,
[BPF_JMP | BPF_JSET | BPF_K] = true,
[BPF_JMP | BPF_JSET | BPF_X] = true,
};
if (code_to_probe >= ARRAY_SIZE(codes))
return false;
return codes[code_to_probe];
}
static bool bpf_check_basics_ok(const struct sock_filter *filter,
unsigned int flen)
{
if (filter == NULL)
return false;
if (flen == 0 || flen > BPF_MAXINSNS)
return false;
return true;
}
/**
* bpf_check_classic - verify socket filter code
* @filter: filter to verify
* @flen: length of filter
*
* Check the user's filter code. If we let some ugly
* filter code slip through kaboom! The filter must contain
* no references or jumps that are out of range, no illegal
* instructions, and must end with a RET instruction.
*
* All jumps are forward as they are not signed.
*
* Returns 0 if the rule set is legal or -EINVAL if not.
*/
static int bpf_check_classic(const struct sock_filter *filter,
unsigned int flen)
{
bool anc_found;
int pc;
/* Check the filter code now */
for (pc = 0; pc < flen; pc++) {
const struct sock_filter *ftest = &filter[pc];
/* May we actually operate on this code? */
if (!chk_code_allowed(ftest->code))
return -EINVAL;
/* Some instructions need special checks */
switch (ftest->code) {
case BPF_ALU | BPF_DIV | BPF_K:
case BPF_ALU | BPF_MOD | BPF_K:
/* Check for division by zero */
if (ftest->k == 0)
return -EINVAL;
break;
case BPF_ALU | BPF_LSH | BPF_K:
case BPF_ALU | BPF_RSH | BPF_K:
if (ftest->k >= 32)
return -EINVAL;
break;
case BPF_LD | BPF_MEM:
case BPF_LDX | BPF_MEM:
case BPF_ST:
case BPF_STX:
/* Check for invalid memory addresses */
if (ftest->k >= BPF_MEMWORDS)
return -EINVAL;
break;
case BPF_JMP | BPF_JA:
/* Note, the large ftest->k might cause loops.
* Compare this with conditional jumps below,
* where offsets are limited. --ANK (981016)
*/
if (ftest->k >= (unsigned int)(flen - pc - 1))
return -EINVAL;
break;
case BPF_JMP | BPF_JEQ | BPF_K:
case BPF_JMP | BPF_JEQ | BPF_X:
case BPF_JMP | BPF_JGE | BPF_K:
case BPF_JMP | BPF_JGE | BPF_X:
case BPF_JMP | BPF_JGT | BPF_K:
case BPF_JMP | BPF_JGT | BPF_X:
case BPF_JMP | BPF_JSET | BPF_K:
case BPF_JMP | BPF_JSET | BPF_X:
/* Both conditionals must be safe */
if (pc + ftest->jt + 1 >= flen ||
pc + ftest->jf + 1 >= flen)
return -EINVAL;
break;
case BPF_LD | BPF_W | BPF_ABS:
case BPF_LD | BPF_H | BPF_ABS:
case BPF_LD | BPF_B | BPF_ABS:
anc_found = false;
if (bpf_anc_helper(ftest) & BPF_ANC)
anc_found = true;
/* Ancillary operation unknown or unsupported */
if (anc_found == false && ftest->k >= SKF_AD_OFF)
return -EINVAL;
}
}
/* Last instruction must be a RET code */
switch (filter[flen - 1].code) {
case BPF_RET | BPF_K:
case BPF_RET | BPF_A:
return check_load_and_stores(filter, flen);
}
return -EINVAL;
}
static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
const struct sock_fprog *fprog)
{
unsigned int fsize = bpf_classic_proglen(fprog);
struct sock_fprog_kern *fkprog;
fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
if (!fp->orig_prog)
return -ENOMEM;
fkprog = fp->orig_prog;
fkprog->len = fprog->len;
fkprog->filter = kmemdup(fp->insns, fsize,
GFP_KERNEL | __GFP_NOWARN);
if (!fkprog->filter) {
kfree(fp->orig_prog);
return -ENOMEM;
}
return 0;
}
static void bpf_release_orig_filter(struct bpf_prog *fp)
{
struct sock_fprog_kern *fprog = fp->orig_prog;
if (fprog) {
kfree(fprog->filter);
kfree(fprog);
}
}
static void __bpf_prog_release(struct bpf_prog *prog)
{
if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
bpf_prog_put(prog);
} else {
bpf_release_orig_filter(prog);
bpf_prog_free(prog);
}
}
static void __sk_filter_release(struct sk_filter *fp)
{
__bpf_prog_release(fp->prog);
kfree(fp);
}
/**
* sk_filter_release_rcu - Release a socket filter by rcu_head
* @rcu: rcu_head that contains the sk_filter to free
*/
static void sk_filter_release_rcu(struct rcu_head *rcu)
{
struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
__sk_filter_release(fp);
}
/**
* sk_filter_release - release a socket filter
* @fp: filter to remove
*
* Remove a filter from a socket and release its resources.
*/
static void sk_filter_release(struct sk_filter *fp)
{
if (refcount_dec_and_test(&fp->refcnt))
call_rcu(&fp->rcu, sk_filter_release_rcu);
}
void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
{
u32 filter_size = bpf_prog_size(fp->prog->len);
atomic_sub(filter_size, &sk->sk_omem_alloc);
sk_filter_release(fp);
}
/* try to charge the socket memory if there is space available
* return true on success
*/
static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
{
u32 filter_size = bpf_prog_size(fp->prog->len);
/* same check as in sock_kmalloc() */
if (filter_size <= sysctl_optmem_max &&
atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) {
atomic_add(filter_size, &sk->sk_omem_alloc);
return true;
}
return false;
}
bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
{
if (!refcount_inc_not_zero(&fp->refcnt))
return false;
if (!__sk_filter_charge(sk, fp)) {
sk_filter_release(fp);
return false;
}
return true;
}
static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
{
struct sock_filter *old_prog;
struct bpf_prog *old_fp;
int err, new_len, old_len = fp->len;
bool seen_ld_abs = false;
/* We are free to overwrite insns et al right here as it
* won't be used at this point in time anymore internally
* after the migration to the internal BPF instruction
* representation.
*/
BUILD_BUG_ON(sizeof(struct sock_filter) !=
sizeof(struct bpf_insn));
/* Conversion cannot happen on overlapping memory areas,
* so we need to keep the user BPF around until the 2nd
* pass. At this time, the user BPF is stored in fp->insns.
*/
old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
GFP_KERNEL | __GFP_NOWARN);
if (!old_prog) {
err = -ENOMEM;
goto out_err;
}
/* 1st pass: calculate the new program length. */
err = bpf_convert_filter(old_prog, old_len, NULL, &new_len,
&seen_ld_abs);
if (err)
goto out_err_free;
/* Expand fp for appending the new filter representation. */
old_fp = fp;
fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
if (!fp) {
/* The old_fp is still around in case we couldn't
* allocate new memory, so uncharge on that one.
*/
fp = old_fp;
err = -ENOMEM;
goto out_err_free;
}
fp->len = new_len;
/* 2nd pass: remap sock_filter insns into bpf_insn insns. */
err = bpf_convert_filter(old_prog, old_len, fp, &new_len,
&seen_ld_abs);
if (err)
/* 2nd bpf_convert_filter() can fail only if it fails
* to allocate memory, remapping must succeed. Note,
* that at this time old_fp has already been released
* by krealloc().
*/
goto out_err_free;
fp = bpf_prog_select_runtime(fp, &err);
if (err)
goto out_err_free;
kfree(old_prog);
return fp;
out_err_free:
kfree(old_prog);
out_err:
__bpf_prog_release(fp);
return ERR_PTR(err);
}
static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
bpf_aux_classic_check_t trans)
{
int err;
fp->bpf_func = NULL;
fp->jited = 0;
err = bpf_check_classic(fp->insns, fp->len);
if (err) {
__bpf_prog_release(fp);
return ERR_PTR(err);
}
/* There might be additional checks and transformations
* needed on classic filters, f.e. in case of seccomp.
*/
if (trans) {
err = trans(fp->insns, fp->len);
if (err) {
__bpf_prog_release(fp);
return ERR_PTR(err);
}
}
/* Probe if we can JIT compile the filter and if so, do
* the compilation of the filter.
*/
bpf_jit_compile(fp);
/* JIT compiler couldn't process this filter, so do the
* internal BPF translation for the optimized interpreter.
*/
if (!fp->jited)
fp = bpf_migrate_filter(fp);
return fp;
}
/**
* bpf_prog_create - create an unattached filter
* @pfp: the unattached filter that is created
* @fprog: the filter program
*
* Create a filter independent of any socket. We first run some
* sanity checks on it to make sure it does not explode on us later.
* If an error occurs or there is insufficient memory for the filter
* a negative errno code is returned. On success the return is zero.
*/
int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
{
unsigned int fsize = bpf_classic_proglen(fprog);
struct bpf_prog *fp;
/* Make sure new filter is there and in the right amounts. */
if (!bpf_check_basics_ok(fprog->filter, fprog->len))
return -EINVAL;
fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
if (!fp)
return -ENOMEM;
memcpy(fp->insns, fprog->filter, fsize);
fp->len = fprog->len;
/* Since unattached filters are not copied back to user
* space through sk_get_filter(), we do not need to hold
* a copy here, and can spare us the work.
*/
fp->orig_prog = NULL;
/* bpf_prepare_filter() already takes care of freeing
* memory in case something goes wrong.
*/
fp = bpf_prepare_filter(fp, NULL);
if (IS_ERR(fp))
return PTR_ERR(fp);
*pfp = fp;
return 0;
}
EXPORT_SYMBOL_GPL(bpf_prog_create);
/**
* bpf_prog_create_from_user - create an unattached filter from user buffer
* @pfp: the unattached filter that is created
* @fprog: the filter program
* @trans: post-classic verifier transformation handler
* @save_orig: save classic BPF program
*
* This function effectively does the same as bpf_prog_create(), only
* that it builds up its insns buffer from user space provided buffer.
* It also allows for passing a bpf_aux_classic_check_t handler.
*/
int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
bpf_aux_classic_check_t trans, bool save_orig)
{
unsigned int fsize = bpf_classic_proglen(fprog);
struct bpf_prog *fp;
int err;
/* Make sure new filter is there and in the right amounts. */
if (!bpf_check_basics_ok(fprog->filter, fprog->len))
return -EINVAL;
fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
if (!fp)
return -ENOMEM;
if (copy_from_user(fp->insns, fprog->filter, fsize)) {
__bpf_prog_free(fp);
return -EFAULT;
}
fp->len = fprog->len;
fp->orig_prog = NULL;
if (save_orig) {
err = bpf_prog_store_orig_filter(fp, fprog);
if (err) {
__bpf_prog_free(fp);
return -ENOMEM;
}
}
/* bpf_prepare_filter() already takes care of freeing
* memory in case something goes wrong.
*/
fp = bpf_prepare_filter(fp, trans);
if (IS_ERR(fp))
return PTR_ERR(fp);
*pfp = fp;
return 0;
}
EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);
void bpf_prog_destroy(struct bpf_prog *fp)
{
__bpf_prog_release(fp);
}
EXPORT_SYMBOL_GPL(bpf_prog_destroy);
static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
{
struct sk_filter *fp, *old_fp;
fp = kmalloc(sizeof(*fp), GFP_KERNEL);
if (!fp)
return -ENOMEM;
fp->prog = prog;
if (!__sk_filter_charge(sk, fp)) {
kfree(fp);
return -ENOMEM;
}
refcount_set(&fp->refcnt, 1);
old_fp = rcu_dereference_protected(sk->sk_filter,
lockdep_sock_is_held(sk));
rcu_assign_pointer(sk->sk_filter, fp);
if (old_fp)
sk_filter_uncharge(sk, old_fp);
return 0;
}
static
struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
{
unsigned int fsize = bpf_classic_proglen(fprog);
struct bpf_prog *prog;
int err;
if (sock_flag(sk, SOCK_FILTER_LOCKED))
return ERR_PTR(-EPERM);
/* Make sure new filter is there and in the right amounts. */
if (!bpf_check_basics_ok(fprog->filter, fprog->len))
return ERR_PTR(-EINVAL);
prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
if (!prog)
return ERR_PTR(-ENOMEM);
if (copy_from_user(prog->insns, fprog->filter, fsize)) {
__bpf_prog_free(prog);
return ERR_PTR(-EFAULT);
}
prog->len = fprog->len;
err = bpf_prog_store_orig_filter(prog, fprog);
if (err) {
__bpf_prog_free(prog);
return ERR_PTR(-ENOMEM);
}
/* bpf_prepare_filter() already takes care of freeing
* memory in case something goes wrong.
*/
return bpf_prepare_filter(prog, NULL);
}
/**
* sk_attach_filter - attach a socket filter
* @fprog: the filter program
* @sk: the socket to use
*
* Attach the user's filter code. We first run some sanity checks on
* it to make sure it does not explode on us later. If an error
* occurs or there is insufficient memory for the filter a negative
* errno code is returned. On success the return is zero.
*/
int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
{
struct bpf_prog *prog = __get_filter(fprog, sk);
int err;
if (IS_ERR(prog))
return PTR_ERR(prog);
err = __sk_attach_prog(prog, sk);
if (err < 0) {
__bpf_prog_release(prog);
return err;
}
return 0;
}
EXPORT_SYMBOL_GPL(sk_attach_filter);
int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
{
struct bpf_prog *prog = __get_filter(fprog, sk);
int err;
if (IS_ERR(prog))
return PTR_ERR(prog);
if (bpf_prog_size(prog->len) > sysctl_optmem_max)
err = -ENOMEM;
else
err = reuseport_attach_prog(sk, prog);
if (err)
__bpf_prog_release(prog);
return err;
}
static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
{
if (sock_flag(sk, SOCK_FILTER_LOCKED))
return ERR_PTR(-EPERM);
return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
}
int sk_attach_bpf(u32 ufd, struct sock *sk)
{
struct bpf_prog *prog = __get_bpf(ufd, sk);
int err;
if (IS_ERR(prog))
return PTR_ERR(prog);
err = __sk_attach_prog(prog, sk);
if (err < 0) {
bpf_prog_put(prog);
return err;
}
return 0;
}
int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
{
struct bpf_prog *prog;
int err;
if (sock_flag(sk, SOCK_FILTER_LOCKED))
return -EPERM;
prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
if (IS_ERR(prog) && PTR_ERR(prog) == -EINVAL)
prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SK_REUSEPORT);
if (IS_ERR(prog))
return PTR_ERR(prog);
if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT) {
/* Like other non BPF_PROG_TYPE_SOCKET_FILTER
* bpf prog (e.g. sockmap). It depends on the
* limitation imposed by bpf_prog_load().
* Hence, sysctl_optmem_max is not checked.
*/
if ((sk->sk_type != SOCK_STREAM &&
sk->sk_type != SOCK_DGRAM) ||
(sk->sk_protocol != IPPROTO_UDP &&
sk->sk_protocol != IPPROTO_TCP) ||
(sk->sk_family != AF_INET &&
sk->sk_family != AF_INET6)) {
err = -ENOTSUPP;
goto err_prog_put;
}
} else {
/* BPF_PROG_TYPE_SOCKET_FILTER */
if (bpf_prog_size(prog->len) > sysctl_optmem_max) {
err = -ENOMEM;
goto err_prog_put;
}
}
err = reuseport_attach_prog(sk, prog);
err_prog_put:
if (err)
bpf_prog_put(prog);
return err;
}
void sk_reuseport_prog_free(struct bpf_prog *prog)
{
if (!prog)
return;
if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT)
bpf_prog_put(prog);
else
bpf_prog_destroy(prog);
}
struct bpf_scratchpad {
union {
__be32 diff[MAX_BPF_STACK / sizeof(__be32)];
u8 buff[MAX_BPF_STACK];
};
};
static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp);
static inline int __bpf_try_make_writable(struct sk_buff *skb,
unsigned int write_len)
{
return skb_ensure_writable(skb, write_len);
}
static inline int bpf_try_make_writable(struct sk_buff *skb,
unsigned int write_len)
{
int err = __bpf_try_make_writable(skb, write_len);
bpf_compute_data_pointers(skb);
return err;
}
static int bpf_try_make_head_writable(struct sk_buff *skb)
{
return bpf_try_make_writable(skb, skb_headlen(skb));
}
static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
{
if (skb_at_tc_ingress(skb))
skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
}
static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
{
if (skb_at_tc_ingress(skb))
skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
}
BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
const void *, from, u32, len, u64, flags)
{
void *ptr;
if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
return -EINVAL;
if (unlikely(offset > 0xffff))
return -EFAULT;
if (unlikely(bpf_try_make_writable(skb, offset + len)))
return -EFAULT;
ptr = skb->data + offset;
if (flags & BPF_F_RECOMPUTE_CSUM)
__skb_postpull_rcsum(skb, ptr, len, offset);
memcpy(ptr, from, len);
if (flags & BPF_F_RECOMPUTE_CSUM)
__skb_postpush_rcsum(skb, ptr, len, offset);
if (flags & BPF_F_INVALIDATE_HASH)
skb_clear_hash(skb);
return 0;
}
static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
.func = bpf_skb_store_bytes,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_PTR_TO_MEM,
.arg4_type = ARG_CONST_SIZE,
.arg5_type = ARG_ANYTHING,
};
BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
void *, to, u32, len)
{
void *ptr;
if (unlikely(offset > 0xffff))
goto err_clear;
ptr = skb_header_pointer(skb, offset, len, to);
if (unlikely(!ptr))
goto err_clear;
if (ptr != to)
memcpy(to, ptr, len);
return 0;
err_clear:
memset(to, 0, len);
return -EFAULT;
}
static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
.func = bpf_skb_load_bytes,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_PTR_TO_UNINIT_MEM,
.arg4_type = ARG_CONST_SIZE,
};
BPF_CALL_5(bpf_skb_load_bytes_relative, const struct sk_buff *, skb,
u32, offset, void *, to, u32, len, u32, start_header)
{
u8 *end = skb_tail_pointer(skb);
u8 *net = skb_network_header(skb);
u8 *mac = skb_mac_header(skb);
u8 *ptr;
if (unlikely(offset > 0xffff || len > (end - mac)))
goto err_clear;
switch (start_header) {
case BPF_HDR_START_MAC:
ptr = mac + offset;
break;
case BPF_HDR_START_NET:
ptr = net + offset;
break;
default:
goto err_clear;
}
if (likely(ptr >= mac && ptr + len <= end)) {
memcpy(to, ptr, len);
return 0;
}
err_clear:
memset(to, 0, len);
return -EFAULT;
}
static const struct bpf_func_proto bpf_skb_load_bytes_relative_proto = {
.func = bpf_skb_load_bytes_relative,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_PTR_TO_UNINIT_MEM,
.arg4_type = ARG_CONST_SIZE,
.arg5_type = ARG_ANYTHING,
};
BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
{
/* Idea is the following: should the needed direct read/write
* test fail during runtime, we can pull in more data and redo
* again, since implicitly, we invalidate previous checks here.
*
* Or, since we know how much we need to make read/writeable,
* this can be done once at the program beginning for direct
* access case. By this we overcome limitations of only current
* headroom being accessible.
*/
return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
}
static const struct bpf_func_proto bpf_skb_pull_data_proto = {
.func = bpf_skb_pull_data,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
static inline int sk_skb_try_make_writable(struct sk_buff *skb,
unsigned int write_len)
{
int err = __bpf_try_make_writable(skb, write_len);
bpf_compute_data_end_sk_skb(skb);
return err;
}
BPF_CALL_2(sk_skb_pull_data, struct sk_buff *, skb, u32, len)
{
/* Idea is the following: should the needed direct read/write
* test fail during runtime, we can pull in more data and redo
* again, since implicitly, we invalidate previous checks here.
*
* Or, since we know how much we need to make read/writeable,
* this can be done once at the program beginning for direct
* access case. By this we overcome limitations of only current
* headroom being accessible.
*/
return sk_skb_try_make_writable(skb, len ? : skb_headlen(skb));
}
static const struct bpf_func_proto sk_skb_pull_data_proto = {
.func = sk_skb_pull_data,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
u64, from, u64, to, u64, flags)
{
__sum16 *ptr;
if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
return -EINVAL;
if (unlikely(offset > 0xffff || offset & 1))
return -EFAULT;
if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
return -EFAULT;
ptr = (__sum16 *)(skb->data + offset);
switch (flags & BPF_F_HDR_FIELD_MASK) {
case 0:
if (unlikely(from != 0))
return -EINVAL;
csum_replace_by_diff(ptr, to);
break;
case 2:
csum_replace2(ptr, from, to);
break;
case 4:
csum_replace4(ptr, from, to);
break;
default:
return -EINVAL;
}
return 0;
}
static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
.func = bpf_l3_csum_replace,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_ANYTHING,
.arg5_type = ARG_ANYTHING,
};
BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
u64, from, u64, to, u64, flags)
{
bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
bool do_mforce = flags & BPF_F_MARK_ENFORCE;
__sum16 *ptr;
if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK)))
return -EINVAL;
if (unlikely(offset > 0xffff || offset & 1))
return -EFAULT;
if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
return -EFAULT;
ptr = (__sum16 *)(skb->data + offset);
if (is_mmzero && !do_mforce && !*ptr)
return 0;
switch (flags & BPF_F_HDR_FIELD_MASK) {
case 0:
if (unlikely(from != 0))
return -EINVAL;
inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo);
break;
case 2:
inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
break;
case 4:
inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
break;
default:
return -EINVAL;
}
if (is_mmzero && !*ptr)
*ptr = CSUM_MANGLED_0;
return 0;
}
static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
.func = bpf_l4_csum_replace,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_ANYTHING,
.arg5_type = ARG_ANYTHING,
};
BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
__be32 *, to, u32, to_size, __wsum, seed)
{
struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp);
u32 diff_size = from_size + to_size;
int i, j = 0;
/* This is quite flexible, some examples:
*
* from_size == 0, to_size > 0, seed := csum --> pushing data
* from_size > 0, to_size == 0, seed := csum --> pulling data
* from_size > 0, to_size > 0, seed := 0 --> diffing data
*
* Even for diffing, from_size and to_size don't need to be equal.
*/
if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) ||
diff_size > sizeof(sp->diff)))
return -EINVAL;
for (i = 0; i < from_size / sizeof(__be32); i++, j++)
sp->diff[j] = ~from[i];
for (i = 0; i < to_size / sizeof(__be32); i++, j++)
sp->diff[j] = to[i];
return csum_partial(sp->diff, diff_size, seed);
}
static const struct bpf_func_proto bpf_csum_diff_proto = {
.func = bpf_csum_diff,
.gpl_only = false,
.pkt_access = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_MEM_OR_NULL,
.arg2_type = ARG_CONST_SIZE_OR_ZERO,
.arg3_type = ARG_PTR_TO_MEM_OR_NULL,
.arg4_type = ARG_CONST_SIZE_OR_ZERO,
.arg5_type = ARG_ANYTHING,
};
BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
{
/* The interface is to be used in combination with bpf_csum_diff()
* for direct packet writes. csum rotation for alignment as well
* as emulating csum_sub() can be done from the eBPF program.
*/
if (skb->ip_summed == CHECKSUM_COMPLETE)
return (skb->csum = csum_add(skb->csum, csum));
return -ENOTSUPP;
}
static const struct bpf_func_proto bpf_csum_update_proto = {
.func = bpf_csum_update,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
{
return dev_forward_skb(dev, skb);
}
static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
struct sk_buff *skb)
{
int ret = ____dev_forward_skb(dev, skb);
if (likely(!ret)) {
skb->dev = dev;
ret = netif_rx(skb);
}
return ret;
}
static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
{
int ret;
if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) {
net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
kfree_skb(skb);
return -ENETDOWN;
}
skb->dev = dev;
__this_cpu_inc(xmit_recursion);
ret = dev_queue_xmit(skb);
__this_cpu_dec(xmit_recursion);
return ret;
}
static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
u32 flags)
{
/* skb->mac_len is not set on normal egress */
unsigned int mlen = skb->network_header - skb->mac_header;
__skb_pull(skb, mlen);
/* At ingress, the mac header has already been pulled once.
* At egress, skb_pospull_rcsum has to be done in case that
* the skb is originated from ingress (i.e. a forwarded skb)
* to ensure that rcsum starts at net header.
*/
if (!skb_at_tc_ingress(skb))
skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
skb_pop_mac_header(skb);
skb_reset_mac_len(skb);
return flags & BPF_F_INGRESS ?
__bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
}
static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
u32 flags)
{
/* Verify that a link layer header is carried */
if (unlikely(skb->mac_header >= skb->network_header)) {
kfree_skb(skb);
return -ERANGE;
}
bpf_push_mac_rcsum(skb);
return flags & BPF_F_INGRESS ?
__bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
}
static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
u32 flags)
{
if (dev_is_mac_header_xmit(dev))
return __bpf_redirect_common(skb, dev, flags);
else
return __bpf_redirect_no_mac(skb, dev, flags);
}
BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
{
struct net_device *dev;
struct sk_buff *clone;
int ret;
if (unlikely(flags & ~(BPF_F_INGRESS)))
return -EINVAL;
dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
if (unlikely(!dev))
return -EINVAL;
clone = skb_clone(skb, GFP_ATOMIC);
if (unlikely(!clone))
return -ENOMEM;
/* For direct write, we need to keep the invariant that the skbs
* we're dealing with need to be uncloned. Should uncloning fail
* here, we need to free the just generated clone to unclone once
* again.
*/
ret = bpf_try_make_head_writable(skb);
if (unlikely(ret)) {
kfree_skb(clone);
return -ENOMEM;
}
return __bpf_redirect(clone, dev, flags);
}
static const struct bpf_func_proto bpf_clone_redirect_proto = {
.func = bpf_clone_redirect,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
DEFINE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
EXPORT_PER_CPU_SYMBOL_GPL(bpf_redirect_info);
BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
if (unlikely(flags & ~(BPF_F_INGRESS)))
return TC_ACT_SHOT;
ri->ifindex = ifindex;
ri->flags = flags;
return TC_ACT_REDIRECT;
}
int skb_do_redirect(struct sk_buff *skb)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
struct net_device *dev;
dev = dev_get_by_index_rcu(dev_net(skb->dev), ri->ifindex);
ri->ifindex = 0;
if (unlikely(!dev)) {
kfree_skb(skb);
return -EINVAL;
}
return __bpf_redirect(skb, dev, ri->flags);
}
static const struct bpf_func_proto bpf_redirect_proto = {
.func = bpf_redirect,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_ANYTHING,
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_4(bpf_sk_redirect_hash, struct sk_buff *, skb,
struct bpf_map *, map, void *, key, u64, flags)
{
struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
/* If user passes invalid input drop the packet. */
if (unlikely(flags & ~(BPF_F_INGRESS)))
return SK_DROP;
tcb->bpf.flags = flags;
tcb->bpf.sk_redir = __sock_hash_lookup_elem(map, key);
if (!tcb->bpf.sk_redir)
return SK_DROP;
return SK_PASS;
}
static const struct bpf_func_proto bpf_sk_redirect_hash_proto = {
.func = bpf_sk_redirect_hash,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_PTR_TO_MAP_KEY,
.arg4_type = ARG_ANYTHING,
};
BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb,
struct bpf_map *, map, u32, key, u64, flags)
{
struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
/* If user passes invalid input drop the packet. */
if (unlikely(flags & ~(BPF_F_INGRESS)))
return SK_DROP;
tcb->bpf.flags = flags;
tcb->bpf.sk_redir = __sock_map_lookup_elem(map, key);
if (!tcb->bpf.sk_redir)
return SK_DROP;
return SK_PASS;
}
struct sock *do_sk_redirect_map(struct sk_buff *skb)
{
struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
return tcb->bpf.sk_redir;
}
static const struct bpf_func_proto bpf_sk_redirect_map_proto = {
.func = bpf_sk_redirect_map,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_ANYTHING,
};
BPF_CALL_4(bpf_msg_redirect_hash, struct sk_msg_buff *, msg,
struct bpf_map *, map, void *, key, u64, flags)
{
/* If user passes invalid input drop the packet. */
if (unlikely(flags & ~(BPF_F_INGRESS)))
return SK_DROP;
msg->flags = flags;
msg->sk_redir = __sock_hash_lookup_elem(map, key);
if (!msg->sk_redir)
return SK_DROP;
return SK_PASS;
}
static const struct bpf_func_proto bpf_msg_redirect_hash_proto = {
.func = bpf_msg_redirect_hash,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_PTR_TO_MAP_KEY,
.arg4_type = ARG_ANYTHING,
};
BPF_CALL_4(bpf_msg_redirect_map, struct sk_msg_buff *, msg,
struct bpf_map *, map, u32, key, u64, flags)
{
/* If user passes invalid input drop the packet. */
if (unlikely(flags & ~(BPF_F_INGRESS)))
return SK_DROP;
msg->flags = flags;
msg->sk_redir = __sock_map_lookup_elem(map, key);
if (!msg->sk_redir)
return SK_DROP;
return SK_PASS;
}
struct sock *do_msg_redirect_map(struct sk_msg_buff *msg)
{
return msg->sk_redir;
}
static const struct bpf_func_proto bpf_msg_redirect_map_proto = {
.func = bpf_msg_redirect_map,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_ANYTHING,
};
BPF_CALL_2(bpf_msg_apply_bytes, struct sk_msg_buff *, msg, u32, bytes)
{
msg->apply_bytes = bytes;
return 0;
}
static const struct bpf_func_proto bpf_msg_apply_bytes_proto = {
.func = bpf_msg_apply_bytes,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg_buff *, msg, u32, bytes)
{
msg->cork_bytes = bytes;
return 0;
}
static const struct bpf_func_proto bpf_msg_cork_bytes_proto = {
.func = bpf_msg_cork_bytes,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_4(bpf_msg_pull_data,
struct sk_msg_buff *, msg, u32, start, u32, end, u64, flags)
{
unsigned int len = 0, offset = 0, copy = 0;
struct scatterlist *sg = msg->sg_data;
int first_sg, last_sg, i, shift;
unsigned char *p, *to, *from;
int bytes = end - start;
struct page *page;
if (unlikely(flags || end <= start))
return -EINVAL;
/* First find the starting scatterlist element */
i = msg->sg_start;
do {
len = sg[i].length;
offset += len;
if (start < offset + len)
break;
i++;
if (i == MAX_SKB_FRAGS)
i = 0;
} while (i != msg->sg_end);
if (unlikely(start >= offset + len))
return -EINVAL;
if (!msg->sg_copy[i] && bytes <= len)
goto out;
first_sg = i;
/* At this point we need to linearize multiple scatterlist
* elements or a single shared page. Either way we need to
* copy into a linear buffer exclusively owned by BPF. Then
* place the buffer in the scatterlist and fixup the original
* entries by removing the entries now in the linear buffer
* and shifting the remaining entries. For now we do not try
* to copy partial entries to avoid complexity of running out
* of sg_entry slots. The downside is reading a single byte
* will copy the entire sg entry.
*/
do {
copy += sg[i].length;
i++;
if (i == MAX_SKB_FRAGS)
i = 0;
if (bytes < copy)
break;
} while (i != msg->sg_end);
last_sg = i;
if (unlikely(copy < end - start))
return -EINVAL;
page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC, get_order(copy));
if (unlikely(!page))
return -ENOMEM;
p = page_address(page);
offset = 0;
i = first_sg;
do {
from = sg_virt(&sg[i]);
len = sg[i].length;
to = p + offset;
memcpy(to, from, len);
offset += len;
sg[i].length = 0;
put_page(sg_page(&sg[i]));
i++;
if (i == MAX_SKB_FRAGS)
i = 0;
} while (i != last_sg);
sg[first_sg].length = copy;
sg_set_page(&sg[first_sg], page, copy, 0);
/* To repair sg ring we need to shift entries. If we only
* had a single entry though we can just replace it and
* be done. Otherwise walk the ring and shift the entries.
*/
shift = last_sg - first_sg - 1;
if (!shift)
goto out;
i = first_sg + 1;
do {
int move_from;
if (i + shift >= MAX_SKB_FRAGS)
move_from = i + shift - MAX_SKB_FRAGS;
else
move_from = i + shift;
if (move_from == msg->sg_end)
break;
sg[i] = sg[move_from];
sg[move_from].length = 0;
sg[move_from].page_link = 0;
sg[move_from].offset = 0;
i++;
if (i == MAX_SKB_FRAGS)
i = 0;
} while (1);
msg->sg_end -= shift;
if (msg->sg_end < 0)
msg->sg_end += MAX_SKB_FRAGS;
out:
msg->data = sg_virt(&sg[i]) + start - offset;
msg->data_end = msg->data + bytes;
return 0;
}
static const struct bpf_func_proto bpf_msg_pull_data_proto = {
.func = bpf_msg_pull_data,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_ANYTHING,
};
BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
{
return task_get_classid(skb);
}
static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
.func = bpf_get_cgroup_classid,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
{
return dst_tclassid(skb);
}
static const struct bpf_func_proto bpf_get_route_realm_proto = {
.func = bpf_get_route_realm,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
{
/* If skb_clear_hash() was called due to mangling, we can
* trigger SW recalculation here. Later access to hash
* can then use the inline skb->hash via context directly
* instead of calling this helper again.
*/
return skb_get_hash(skb);
}
static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
.func = bpf_get_hash_recalc,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
{
/* After all direct packet write, this can be used once for
* triggering a lazy recalc on next skb_get_hash() invocation.
*/
skb_clear_hash(skb);
return 0;
}
static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
.func = bpf_set_hash_invalid,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
{
/* Set user specified hash as L4(+), so that it gets returned
* on skb_get_hash() call unless BPF prog later on triggers a
* skb_clear_hash().
*/
__skb_set_sw_hash(skb, hash, true);
return 0;
}
static const struct bpf_func_proto bpf_set_hash_proto = {
.func = bpf_set_hash,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
u16, vlan_tci)
{
int ret;
if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
vlan_proto != htons(ETH_P_8021AD)))
vlan_proto = htons(ETH_P_8021Q);
bpf_push_mac_rcsum(skb);
ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
bpf_pull_mac_rcsum(skb);
bpf_compute_data_pointers(skb);
return ret;
}
static const struct bpf_func_proto bpf_skb_vlan_push_proto = {
.func = bpf_skb_vlan_push,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
{
int ret;
bpf_push_mac_rcsum(skb);
ret = skb_vlan_pop(skb);
bpf_pull_mac_rcsum(skb);
bpf_compute_data_pointers(skb);
return ret;
}
static const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
.func = bpf_skb_vlan_pop,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
{
/* Caller already did skb_cow() with len as headroom,
* so no need to do it here.
*/
skb_push(skb, len);
memmove(skb->data, skb->data + len, off);
memset(skb->data + off, 0, len);
/* No skb_postpush_rcsum(skb, skb->data + off, len)
* needed here as it does not change the skb->csum
* result for checksum complete when summing over
* zeroed blocks.
*/
return 0;
}
static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
{
/* skb_ensure_writable() is not needed here, as we're
* already working on an uncloned skb.
*/
if (unlikely(!pskb_may_pull(skb, off + len)))
return -ENOMEM;
skb_postpull_rcsum(skb, skb->data + off, len);
memmove(skb->data + len, skb->data, off);
__skb_pull(skb, len);
return 0;
}
static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
{
bool trans_same = skb->transport_header == skb->network_header;
int ret;
/* There's no need for __skb_push()/__skb_pull() pair to
* get to the start of the mac header as we're guaranteed
* to always start from here under eBPF.
*/
ret = bpf_skb_generic_push(skb, off, len);
if (likely(!ret)) {
skb->mac_header -= len;
skb->network_header -= len;
if (trans_same)
skb->transport_header = skb->network_header;
}
return ret;
}
static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
{
bool trans_same = skb->transport_header == skb->network_header;
int ret;
/* Same here, __skb_push()/__skb_pull() pair not needed. */
ret = bpf_skb_generic_pop(skb, off, len);
if (likely(!ret)) {
skb->mac_header += len;
skb->network_header += len;
if (trans_same)
skb->transport_header = skb->network_header;
}
return ret;
}
static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
{
const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
u32 off = skb_mac_header_len(skb);
int ret;
/* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */
if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb)))
return -ENOTSUPP;
ret = skb_cow(skb, len_diff);
if (unlikely(ret < 0))
return ret;
ret = bpf_skb_net_hdr_push(skb, off, len_diff);
if (unlikely(ret < 0))
return ret;
if (skb_is_gso(skb)) {
struct skb_shared_info *shinfo = skb_shinfo(skb);
/* SKB_GSO_TCPV4 needs to be changed into
* SKB_GSO_TCPV6.
*/
if (shinfo->gso_type & SKB_GSO_TCPV4) {
shinfo->gso_type &= ~SKB_GSO_TCPV4;
shinfo->gso_type |= SKB_GSO_TCPV6;
}
/* Due to IPv6 header, MSS needs to be downgraded. */
skb_decrease_gso_size(shinfo, len_diff);
/* Header must be checked, and gso_segs recomputed. */
shinfo->gso_type |= SKB_GSO_DODGY;
shinfo->gso_segs = 0;
}
skb->protocol = htons(ETH_P_IPV6);
skb_clear_hash(skb);
return 0;
}
static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
{
const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
u32 off = skb_mac_header_len(skb);
int ret;
/* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */
if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb)))
return -ENOTSUPP;
ret = skb_unclone(skb, GFP_ATOMIC);
if (unlikely(ret < 0))
return ret;
ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
if (unlikely(ret < 0))
return ret;
if (skb_is_gso(skb)) {
struct skb_shared_info *shinfo = skb_shinfo(skb);
/* SKB_GSO_TCPV6 needs to be changed into
* SKB_GSO_TCPV4.
*/
if (shinfo->gso_type & SKB_GSO_TCPV6) {
shinfo->gso_type &= ~SKB_GSO_TCPV6;
shinfo->gso_type |= SKB_GSO_TCPV4;
}
/* Due to IPv4 header, MSS can be upgraded. */
skb_increase_gso_size(shinfo, len_diff);
/* Header must be checked, and gso_segs recomputed. */
shinfo->gso_type |= SKB_GSO_DODGY;
shinfo->gso_segs = 0;
}
skb->protocol = htons(ETH_P_IP);
skb_clear_hash(skb);
return 0;
}
static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
{
__be16 from_proto = skb->protocol;
if (from_proto == htons(ETH_P_IP) &&
to_proto == htons(ETH_P_IPV6))
return bpf_skb_proto_4_to_6(skb);
if (from_proto == htons(ETH_P_IPV6) &&
to_proto == htons(ETH_P_IP))
return bpf_skb_proto_6_to_4(skb);
return -ENOTSUPP;
}
BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
u64, flags)
{
int ret;
if (unlikely(flags))
return -EINVAL;
/* General idea is that this helper does the basic groundwork
* needed for changing the protocol, and eBPF program fills the
* rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
* and other helpers, rather than passing a raw buffer here.
*
* The rationale is to keep this minimal and without a need to
* deal with raw packet data. F.e. even if we would pass buffers
* here, the program still needs to call the bpf_lX_csum_replace()
* helpers anyway. Plus, this way we keep also separation of
* concerns, since f.e. bpf_skb_store_bytes() should only take
* care of stores.
*
* Currently, additional options and extension header space are
* not supported, but flags register is reserved so we can adapt
* that. For offloads, we mark packet as dodgy, so that headers
* need to be verified first.
*/
ret = bpf_skb_proto_xlat(skb, proto);
bpf_compute_data_pointers(skb);
return ret;
}
static const struct bpf_func_proto bpf_skb_change_proto_proto = {
.func = bpf_skb_change_proto,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
{
/* We only allow a restricted subset to be changed for now. */
if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
!skb_pkt_type_ok(pkt_type)))
return -EINVAL;
skb->pkt_type = pkt_type;
return 0;
}
static const struct bpf_func_proto bpf_skb_change_type_proto = {
.func = bpf_skb_change_type,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
{
switch (skb->protocol) {
case htons(ETH_P_IP):
return sizeof(struct iphdr);
case htons(ETH_P_IPV6):
return sizeof(struct ipv6hdr);
default:
return ~0U;
}
}
static int bpf_skb_net_grow(struct sk_buff *skb, u32 len_diff)
{
u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
int ret;
/* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */
if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb)))
return -ENOTSUPP;
ret = skb_cow(skb, len_diff);
if (unlikely(ret < 0))
return ret;
ret = bpf_skb_net_hdr_push(skb, off, len_diff);
if (unlikely(ret < 0))
return ret;
if (skb_is_gso(skb)) {
struct skb_shared_info *shinfo = skb_shinfo(skb);
/* Due to header grow, MSS needs to be downgraded. */
skb_decrease_gso_size(shinfo, len_diff);
/* Header must be checked, and gso_segs recomputed. */
shinfo->gso_type |= SKB_GSO_DODGY;
shinfo->gso_segs = 0;
}
return 0;
}
static int bpf_skb_net_shrink(struct sk_buff *skb, u32 len_diff)
{
u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
int ret;
/* SCTP uses GSO_BY_FRAGS, thus cannot adjust it. */
if (skb_is_gso(skb) && unlikely(skb_is_gso_sctp(skb)))
return -ENOTSUPP;
ret = skb_unclone(skb, GFP_ATOMIC);
if (unlikely(ret < 0))
return ret;
ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
if (unlikely(ret < 0))
return ret;
if (skb_is_gso(skb)) {
struct skb_shared_info *shinfo = skb_shinfo(skb);
/* Due to header shrink, MSS can be upgraded. */
skb_increase_gso_size(shinfo, len_diff);
/* Header must be checked, and gso_segs recomputed. */
shinfo->gso_type |= SKB_GSO_DODGY;
shinfo->gso_segs = 0;
}
return 0;
}
static u32 __bpf_skb_max_len(const struct sk_buff *skb)
{
return skb->dev ? skb->dev->mtu + skb->dev->hard_header_len :
SKB_MAX_ALLOC;
}
static int bpf_skb_adjust_net(struct sk_buff *skb, s32 len_diff)
{
bool trans_same = skb->transport_header == skb->network_header;
u32 len_cur, len_diff_abs = abs(len_diff);
u32 len_min = bpf_skb_net_base_len(skb);
u32 len_max = __bpf_skb_max_len(skb);
__be16 proto = skb->protocol;
bool shrink = len_diff < 0;
int ret;
if (unlikely(len_diff_abs > 0xfffU))
return -EFAULT;
if (unlikely(proto != htons(ETH_P_IP) &&
proto != htons(ETH_P_IPV6)))
return -ENOTSUPP;
len_cur = skb->len - skb_network_offset(skb);
if (skb_transport_header_was_set(skb) && !trans_same)
len_cur = skb_network_header_len(skb);
if ((shrink && (len_diff_abs >= len_cur ||
len_cur - len_diff_abs < len_min)) ||
(!shrink && (skb->len + len_diff_abs > len_max &&
!skb_is_gso(skb))))
return -ENOTSUPP;
ret = shrink ? bpf_skb_net_shrink(skb, len_diff_abs) :
bpf_skb_net_grow(skb, len_diff_abs);
bpf_compute_data_pointers(skb);
return ret;
}
BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
u32, mode, u64, flags)
{
if (unlikely(flags))
return -EINVAL;
if (likely(mode == BPF_ADJ_ROOM_NET))
return bpf_skb_adjust_net(skb, len_diff);
return -ENOTSUPP;
}
static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
.func = bpf_skb_adjust_room,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_ANYTHING,
};
static u32 __bpf_skb_min_len(const struct sk_buff *skb)
{
u32 min_len = skb_network_offset(skb);
if (skb_transport_header_was_set(skb))
min_len = skb_transport_offset(skb);
if (skb->ip_summed == CHECKSUM_PARTIAL)
min_len = skb_checksum_start_offset(skb) +
skb->csum_offset + sizeof(__sum16);
return min_len;
}
static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
{
unsigned int old_len = skb->len;
int ret;
ret = __skb_grow_rcsum(skb, new_len);
if (!ret)
memset(skb->data + old_len, 0, new_len - old_len);
return ret;
}
static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
{
return __skb_trim_rcsum(skb, new_len);
}
static inline int __bpf_skb_change_tail(struct sk_buff *skb, u32 new_len,
u64 flags)
{
u32 max_len = __bpf_skb_max_len(skb);
u32 min_len = __bpf_skb_min_len(skb);
int ret;
if (unlikely(flags || new_len > max_len || new_len < min_len))
return -EINVAL;
if (skb->encapsulation)
return -ENOTSUPP;
/* The basic idea of this helper is that it's performing the
* needed work to either grow or trim an skb, and eBPF program
* rewrites the rest via helpers like bpf_skb_store_bytes(),
* bpf_lX_csum_replace() and others rather than passing a raw
* buffer here. This one is a slow path helper and intended
* for replies with control messages.
*
* Like in bpf_skb_change_proto(), we want to keep this rather
* minimal and without protocol specifics so that we are able
* to separate concerns as in bpf_skb_store_bytes() should only
* be the one responsible for writing buffers.
*
* It's really expected to be a slow path operation here for
* control message replies, so we're implicitly linearizing,
* uncloning and drop offloads from the skb by this.
*/
ret = __bpf_try_make_writable(skb, skb->len);
if (!ret) {
if (new_len > skb->len)
ret = bpf_skb_grow_rcsum(skb, new_len);
else if (new_len < skb->len)
ret = bpf_skb_trim_rcsum(skb, new_len);
if (!ret && skb_is_gso(skb))
skb_gso_reset(skb);
}
return ret;
}
BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
u64, flags)
{
int ret = __bpf_skb_change_tail(skb, new_len, flags);
bpf_compute_data_pointers(skb);
return ret;
}
static const struct bpf_func_proto bpf_skb_change_tail_proto = {
.func = bpf_skb_change_tail,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
BPF_CALL_3(sk_skb_change_tail, struct sk_buff *, skb, u32, new_len,
u64, flags)
{
int ret = __bpf_skb_change_tail(skb, new_len, flags);
bpf_compute_data_end_sk_skb(skb);
return ret;
}
static const struct bpf_func_proto sk_skb_change_tail_proto = {
.func = sk_skb_change_tail,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
static inline int __bpf_skb_change_head(struct sk_buff *skb, u32 head_room,
u64 flags)
{
u32 max_len = __bpf_skb_max_len(skb);
u32 new_len = skb->len + head_room;
int ret;
if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) ||
new_len < skb->len))
return -EINVAL;
ret = skb_cow(skb, head_room);
if (likely(!ret)) {
/* Idea for this helper is that we currently only
* allow to expand on mac header. This means that
* skb->protocol network header, etc, stay as is.
* Compared to bpf_skb_change_tail(), we're more
* flexible due to not needing to linearize or
* reset GSO. Intention for this helper is to be
* used by an L3 skb that needs to push mac header
* for redirection into L2 device.
*/
__skb_push(skb, head_room);
memset(skb->data, 0, head_room);
skb_reset_mac_header(skb);
}
return ret;
}
BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
u64, flags)
{
int ret = __bpf_skb_change_head(skb, head_room, flags);
bpf_compute_data_pointers(skb);
return ret;
}
static const struct bpf_func_proto bpf_skb_change_head_proto = {
.func = bpf_skb_change_head,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
BPF_CALL_3(sk_skb_change_head, struct sk_buff *, skb, u32, head_room,
u64, flags)
{
int ret = __bpf_skb_change_head(skb, head_room, flags);
bpf_compute_data_end_sk_skb(skb);
return ret;
}
static const struct bpf_func_proto sk_skb_change_head_proto = {
.func = sk_skb_change_head,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
{
return xdp_data_meta_unsupported(xdp) ? 0 :
xdp->data - xdp->data_meta;
}
BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
{
void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
unsigned long metalen = xdp_get_metalen(xdp);
void *data_start = xdp_frame_end + metalen;
void *data = xdp->data + offset;
if (unlikely(data < data_start ||
data > xdp->data_end - ETH_HLEN))
return -EINVAL;
if (metalen)
memmove(xdp->data_meta + offset,
xdp->data_meta, metalen);
xdp->data_meta += offset;
xdp->data = data;
return 0;
}
static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
.func = bpf_xdp_adjust_head,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset)
{
void *data_end = xdp->data_end + offset;
/* only shrinking is allowed for now. */
if (unlikely(offset >= 0))
return -EINVAL;
if (unlikely(data_end < xdp->data + ETH_HLEN))
return -EINVAL;
xdp->data_end = data_end;
return 0;
}
static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = {
.func = bpf_xdp_adjust_tail,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
{
void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
void *meta = xdp->data_meta + offset;
unsigned long metalen = xdp->data - meta;
if (xdp_data_meta_unsupported(xdp))
return -ENOTSUPP;
if (unlikely(meta < xdp_frame_end ||
meta > xdp->data))
return -EINVAL;
if (unlikely((metalen & (sizeof(__u32) - 1)) ||
(metalen > 32)))
return -EACCES;
xdp->data_meta = meta;
return 0;
}
static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
.func = bpf_xdp_adjust_meta,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
static int __bpf_tx_xdp(struct net_device *dev,
struct bpf_map *map,
struct xdp_buff *xdp,
u32 index)
{
struct xdp_frame *xdpf;
int err, sent;
if (!dev->netdev_ops->ndo_xdp_xmit) {
return -EOPNOTSUPP;
}
err = xdp_ok_fwd_dev(dev, xdp->data_end - xdp->data);
if (unlikely(err))
return err;
xdpf = convert_to_xdp_frame(xdp);
if (unlikely(!xdpf))
return -EOVERFLOW;
sent = dev->netdev_ops->ndo_xdp_xmit(dev, 1, &xdpf, XDP_XMIT_FLUSH);
if (sent <= 0)
return sent;
return 0;
}
static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd,
struct bpf_map *map,
struct xdp_buff *xdp,
u32 index)
{
int err;
switch (map->map_type) {
case BPF_MAP_TYPE_DEVMAP: {
struct bpf_dtab_netdev *dst = fwd;
err = dev_map_enqueue(dst, xdp, dev_rx);
if (err)
return err;
__dev_map_insert_ctx(map, index);
break;
}
case BPF_MAP_TYPE_CPUMAP: {
struct bpf_cpu_map_entry *rcpu = fwd;
err = cpu_map_enqueue(rcpu, xdp, dev_rx);
if (err)
return err;
__cpu_map_insert_ctx(map, index);
break;
}
case BPF_MAP_TYPE_XSKMAP: {
struct xdp_sock *xs = fwd;
err = __xsk_map_redirect(map, xdp, xs);
return err;
}
default:
break;
}
return 0;
}
void xdp_do_flush_map(void)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
struct bpf_map *map = ri->map_to_flush;
ri->map_to_flush = NULL;
if (map) {
switch (map->map_type) {
case BPF_MAP_TYPE_DEVMAP:
__dev_map_flush(map);
break;
case BPF_MAP_TYPE_CPUMAP:
__cpu_map_flush(map);
break;
case BPF_MAP_TYPE_XSKMAP:
__xsk_map_flush(map);
break;
default:
break;
}
}
}
EXPORT_SYMBOL_GPL(xdp_do_flush_map);
static void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index)
{
switch (map->map_type) {
case BPF_MAP_TYPE_DEVMAP:
return __dev_map_lookup_elem(map, index);
case BPF_MAP_TYPE_CPUMAP:
return __cpu_map_lookup_elem(map, index);
case BPF_MAP_TYPE_XSKMAP:
return __xsk_map_lookup_elem(map, index);
default:
return NULL;
}
}
static inline bool xdp_map_invalid(const struct bpf_prog *xdp_prog,
unsigned long aux)
{
return (unsigned long)xdp_prog->aux != aux;
}
static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp,
struct bpf_prog *xdp_prog)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
unsigned long map_owner = ri->map_owner;
struct bpf_map *map = ri->map;
u32 index = ri->ifindex;
void *fwd = NULL;
int err;
ri->ifindex = 0;
ri->map = NULL;
ri->map_owner = 0;
if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) {
err = -EFAULT;
map = NULL;
goto err;
}
fwd = __xdp_map_lookup_elem(map, index);
if (!fwd) {
err = -EINVAL;
goto err;
}
if (ri->map_to_flush && ri->map_to_flush != map)
xdp_do_flush_map();
err = __bpf_tx_xdp_map(dev, fwd, map, xdp, index);
if (unlikely(err))
goto err;
ri->map_to_flush = map;
_trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
return 0;
err:
_trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
return err;
}
int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
struct bpf_prog *xdp_prog)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
struct net_device *fwd;
u32 index = ri->ifindex;
int err;
if (ri->map)
return xdp_do_redirect_map(dev, xdp, xdp_prog);
fwd = dev_get_by_index_rcu(dev_net(dev), index);
ri->ifindex = 0;
if (unlikely(!fwd)) {
err = -EINVAL;
goto err;
}
err = __bpf_tx_xdp(fwd, NULL, xdp, 0);
if (unlikely(err))
goto err;
_trace_xdp_redirect(dev, xdp_prog, index);
return 0;
err:
_trace_xdp_redirect_err(dev, xdp_prog, index, err);
return err;
}
EXPORT_SYMBOL_GPL(xdp_do_redirect);
static int xdp_do_generic_redirect_map(struct net_device *dev,
struct sk_buff *skb,
struct xdp_buff *xdp,
struct bpf_prog *xdp_prog)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
unsigned long map_owner = ri->map_owner;
struct bpf_map *map = ri->map;
u32 index = ri->ifindex;
void *fwd = NULL;
int err = 0;
ri->ifindex = 0;
ri->map = NULL;
ri->map_owner = 0;
if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) {
err = -EFAULT;
map = NULL;
goto err;
}
fwd = __xdp_map_lookup_elem(map, index);
if (unlikely(!fwd)) {
err = -EINVAL;
goto err;
}
if (map->map_type == BPF_MAP_TYPE_DEVMAP) {
struct bpf_dtab_netdev *dst = fwd;
err = dev_map_generic_redirect(dst, skb, xdp_prog);
if (unlikely(err))
goto err;
} else if (map->map_type == BPF_MAP_TYPE_XSKMAP) {
struct xdp_sock *xs = fwd;
err = xsk_generic_rcv(xs, xdp);
if (err)
goto err;
consume_skb(skb);
} else {
/* TODO: Handle BPF_MAP_TYPE_CPUMAP */
err = -EBADRQC;
goto err;
}
_trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
return 0;
err:
_trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
return err;
}
int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
struct xdp_buff *xdp, struct bpf_prog *xdp_prog)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
u32 index = ri->ifindex;
struct net_device *fwd;
int err = 0;
if (ri->map)
return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog);
ri->ifindex = 0;
fwd = dev_get_by_index_rcu(dev_net(dev), index);
if (unlikely(!fwd)) {
err = -EINVAL;
goto err;
}
err = xdp_ok_fwd_dev(fwd, skb->len);
if (unlikely(err))
goto err;
skb->dev = fwd;
_trace_xdp_redirect(dev, xdp_prog, index);
generic_xdp_tx(skb, xdp_prog);
return 0;
err:
_trace_xdp_redirect_err(dev, xdp_prog, index, err);
return err;
}
EXPORT_SYMBOL_GPL(xdp_do_generic_redirect);
BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
if (unlikely(flags))
return XDP_ABORTED;
ri->ifindex = ifindex;
ri->flags = flags;
ri->map = NULL;
ri->map_owner = 0;
return XDP_REDIRECT;
}
static const struct bpf_func_proto bpf_xdp_redirect_proto = {
.func = bpf_xdp_redirect,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_ANYTHING,
.arg2_type = ARG_ANYTHING,
};
BPF_CALL_4(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, u64, flags,
unsigned long, map_owner)
{
struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
if (unlikely(flags))
return XDP_ABORTED;
ri->ifindex = ifindex;
ri->flags = flags;
ri->map = map;
ri->map_owner = map_owner;
return XDP_REDIRECT;
}
/* Note, arg4 is hidden from users and populated by the verifier
* with the right pointer.
*/
static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
.func = bpf_xdp_redirect_map,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_CONST_MAP_PTR,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
unsigned long off, unsigned long len)
{
void *ptr = skb_header_pointer(skb, off, len, dst_buff);
if (unlikely(!ptr))
return len;
if (ptr != dst_buff)
memcpy(dst_buff, ptr, len);
return 0;
}
BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
u64, flags, void *, meta, u64, meta_size)
{
u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
return -EINVAL;
if (unlikely(skb_size > skb->len))
return -EFAULT;
return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
bpf_skb_copy);
}
static const struct bpf_func_proto bpf_skb_event_output_proto = {
.func = bpf_skb_event_output,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_PTR_TO_MEM,
.arg5_type = ARG_CONST_SIZE_OR_ZERO,
};
static unsigned short bpf_tunnel_key_af(u64 flags)
{
return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
}
BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
u32, size, u64, flags)
{
const struct ip_tunnel_info *info = skb_tunnel_info(skb);
u8 compat[sizeof(struct bpf_tunnel_key)];
void *to_orig = to;
int err;
if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) {
err = -EINVAL;
goto err_clear;
}
if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
err = -EPROTO;
goto err_clear;
}
if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
err = -EINVAL;
switch (size) {
case offsetof(struct bpf_tunnel_key, tunnel_label):
case offsetof(struct bpf_tunnel_key, tunnel_ext):
goto set_compat;
case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
/* Fixup deprecated structure layouts here, so we have
* a common path later on.
*/
if (ip_tunnel_info_af(info) != AF_INET)
goto err_clear;
set_compat:
to = (struct bpf_tunnel_key *)compat;
break;
default:
goto err_clear;
}
}
to->tunnel_id = be64_to_cpu(info->key.tun_id);
to->tunnel_tos = info->key.tos;
to->tunnel_ttl = info->key.ttl;
to->tunnel_ext = 0;
if (flags & BPF_F_TUNINFO_IPV6) {
memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
sizeof(to->remote_ipv6));
to->tunnel_label = be32_to_cpu(info->key.label);
} else {
to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
to->tunnel_label = 0;
}
if (unlikely(size != sizeof(struct bpf_tunnel_key)))
memcpy(to_orig, to, size);
return 0;
err_clear:
memset(to_orig, 0, size);
return err;
}
static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
.func = bpf_skb_get_tunnel_key,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_PTR_TO_UNINIT_MEM,
.arg3_type = ARG_CONST_SIZE,
.arg4_type = ARG_ANYTHING,
};
BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
{
const struct ip_tunnel_info *info = skb_tunnel_info(skb);
int err;
if (unlikely(!info ||
!(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) {
err = -ENOENT;
goto err_clear;
}
if (unlikely(size < info->options_len)) {
err = -ENOMEM;
goto err_clear;
}
ip_tunnel_info_opts_get(to, info);
if (size > info->options_len)
memset(to + info->options_len, 0, size - info->options_len);
return info->options_len;
err_clear:
memset(to, 0, size);
return err;
}
static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
.func = bpf_skb_get_tunnel_opt,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_PTR_TO_UNINIT_MEM,
.arg3_type = ARG_CONST_SIZE,
};
static struct metadata_dst __percpu *md_dst;
BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
const struct bpf_tunnel_key *, from, u32, size, u64, flags)
{
struct metadata_dst *md = this_cpu_ptr(md_dst);
u8 compat[sizeof(struct bpf_tunnel_key)];
struct ip_tunnel_info *info;
if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
BPF_F_DONT_FRAGMENT | BPF_F_SEQ_NUMBER)))
return -EINVAL;
if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
switch (size) {
case offsetof(struct bpf_tunnel_key, tunnel_label):
case offsetof(struct bpf_tunnel_key, tunnel_ext):
case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
/* Fixup deprecated structure layouts here, so we have
* a common path later on.
*/
memcpy(compat, from, size);
memset(compat + size, 0, sizeof(compat) - size);
from = (const struct bpf_tunnel_key *) compat;
break;
default:
return -EINVAL;
}
}
if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
from->tunnel_ext))
return -EINVAL;
skb_dst_drop(skb);
dst_hold((struct dst_entry *) md);
skb_dst_set(skb, (struct dst_entry *) md);
info = &md->u.tun_info;
memset(info, 0, sizeof(*info));
info->mode = IP_TUNNEL_INFO_TX;
info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
if (flags & BPF_F_DONT_FRAGMENT)
info->key.tun_flags |= TUNNEL_DONT_FRAGMENT;
if (flags & BPF_F_ZERO_CSUM_TX)
info->key.tun_flags &= ~TUNNEL_CSUM;
if (flags & BPF_F_SEQ_NUMBER)
info->key.tun_flags |= TUNNEL_SEQ;
info->key.tun_id = cpu_to_be64(from->tunnel_id);
info->key.tos = from->tunnel_tos;
info->key.ttl = from->tunnel_ttl;
if (flags & BPF_F_TUNINFO_IPV6) {
info->mode |= IP_TUNNEL_INFO_IPV6;
memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
sizeof(from->remote_ipv6));
info->key.label = cpu_to_be32(from->tunnel_label) &
IPV6_FLOWLABEL_MASK;
} else {
info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
}
return 0;
}
static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
.func = bpf_skb_set_tunnel_key,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_PTR_TO_MEM,
.arg3_type = ARG_CONST_SIZE,
.arg4_type = ARG_ANYTHING,
};
BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
const u8 *, from, u32, size)
{
struct ip_tunnel_info *info = skb_tunnel_info(skb);
const struct metadata_dst *md = this_cpu_ptr(md_dst);
if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
return -EINVAL;
if (unlikely(size > IP_TUNNEL_OPTS_MAX))
return -ENOMEM;
ip_tunnel_info_opts_set(info, from, size, TUNNEL_OPTIONS_PRESENT);
return 0;
}
static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
.func = bpf_skb_set_tunnel_opt,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_PTR_TO_MEM,
.arg3_type = ARG_CONST_SIZE,
};
static const struct bpf_func_proto *
bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
{
if (!md_dst) {
struct metadata_dst __percpu *tmp;
tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
METADATA_IP_TUNNEL,
GFP_KERNEL);
if (!tmp)
return NULL;
if (cmpxchg(&md_dst, NULL, tmp))
metadata_dst_free_percpu(tmp);
}
switch (which) {
case BPF_FUNC_skb_set_tunnel_key:
return &bpf_skb_set_tunnel_key_proto;
case BPF_FUNC_skb_set_tunnel_opt:
return &bpf_skb_set_tunnel_opt_proto;
default:
return NULL;
}
}
BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
u32, idx)
{
struct bpf_array *array = container_of(map, struct bpf_array, map);
struct cgroup *cgrp;
struct sock *sk;
sk = skb_to_full_sk(skb);
if (!sk || !sk_fullsock(sk))
return -ENOENT;
if (unlikely(idx >= array->map.max_entries))
return -E2BIG;
cgrp = READ_ONCE(array->ptrs[idx]);
if (unlikely(!cgrp))
return -EAGAIN;
return sk_under_cgroup_hierarchy(sk, cgrp);
}
static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
.func = bpf_skb_under_cgroup,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_ANYTHING,
};
#ifdef CONFIG_SOCK_CGROUP_DATA
BPF_CALL_1(bpf_skb_cgroup_id, const struct sk_buff *, skb)
{
struct sock *sk = skb_to_full_sk(skb);
struct cgroup *cgrp;
if (!sk || !sk_fullsock(sk))
return 0;
cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
return cgrp->kn->id.id;
}
static const struct bpf_func_proto bpf_skb_cgroup_id_proto = {
.func = bpf_skb_cgroup_id,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
#endif
static unsigned long bpf_xdp_copy(void *dst_buff, const void *src_buff,
unsigned long off, unsigned long len)
{
memcpy(dst_buff, src_buff + off, len);
return 0;
}
BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
u64, flags, void *, meta, u64, meta_size)
{
u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
return -EINVAL;
if (unlikely(xdp_size > (unsigned long)(xdp->data_end - xdp->data)))
return -EFAULT;
return bpf_event_output(map, flags, meta, meta_size, xdp->data,
xdp_size, bpf_xdp_copy);
}
static const struct bpf_func_proto bpf_xdp_event_output_proto = {
.func = bpf_xdp_event_output,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_PTR_TO_MEM,
.arg5_type = ARG_CONST_SIZE_OR_ZERO,
};
BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
{
return skb->sk ? sock_gen_cookie(skb->sk) : 0;
}
static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
.func = bpf_get_socket_cookie,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_1(bpf_get_socket_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
{
return sock_gen_cookie(ctx->sk);
}
static const struct bpf_func_proto bpf_get_socket_cookie_sock_addr_proto = {
.func = bpf_get_socket_cookie_sock_addr,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
{
return sock_gen_cookie(ctx->sk);
}
static const struct bpf_func_proto bpf_get_socket_cookie_sock_ops_proto = {
.func = bpf_get_socket_cookie_sock_ops,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
{
struct sock *sk = sk_to_full_sk(skb->sk);
kuid_t kuid;
if (!sk || !sk_fullsock(sk))
return overflowuid;
kuid = sock_net_uid(sock_net(sk), sk);
return from_kuid_munged(sock_net(sk)->user_ns, kuid);
}
static const struct bpf_func_proto bpf_get_socket_uid_proto = {
.func = bpf_get_socket_uid,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
};
BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
int, level, int, optname, char *, optval, int, optlen)
{
struct sock *sk = bpf_sock->sk;
int ret = 0;
int val;
if (!sk_fullsock(sk))
return -EINVAL;
if (level == SOL_SOCKET) {
if (optlen != sizeof(int))
return -EINVAL;
val = *((int *)optval);
/* Only some socketops are supported */
switch (optname) {
case SO_RCVBUF:
sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
break;
case SO_SNDBUF:
sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
break;
case SO_MAX_PACING_RATE:
sk->sk_max_pacing_rate = val;
sk->sk_pacing_rate = min(sk->sk_pacing_rate,
sk->sk_max_pacing_rate);
break;
case SO_PRIORITY:
sk->sk_priority = val;
break;
case SO_RCVLOWAT:
if (val < 0)
val = INT_MAX;
sk->sk_rcvlowat = val ? : 1;
break;
case SO_MARK:
sk->sk_mark = val;
break;
default:
ret = -EINVAL;
}
#ifdef CONFIG_INET
} else if (level == SOL_IP) {
if (optlen != sizeof(int) || sk->sk_family != AF_INET)
return -EINVAL;
val = *((int *)optval);
/* Only some options are supported */
switch (optname) {
case IP_TOS:
if (val < -1 || val > 0xff) {
ret = -EINVAL;
} else {
struct inet_sock *inet = inet_sk(sk);
if (val == -1)
val = 0;
inet->tos = val;
}
break;
default:
ret = -EINVAL;
}
#if IS_ENABLED(CONFIG_IPV6)
} else if (level == SOL_IPV6) {
if (optlen != sizeof(int) || sk->sk_family != AF_INET6)
return -EINVAL;
val = *((int *)optval);
/* Only some options are supported */
switch (optname) {
case IPV6_TCLASS:
if (val < -1 || val > 0xff) {
ret = -EINVAL;
} else {
struct ipv6_pinfo *np = inet6_sk(sk);
if (val == -1)
val = 0;
np->tclass = val;
}
break;
default:
ret = -EINVAL;
}
#endif
} else if (level == SOL_TCP &&
sk->sk_prot->setsockopt == tcp_setsockopt) {
if (optname == TCP_CONGESTION) {
char name[TCP_CA_NAME_MAX];
bool reinit = bpf_sock->op > BPF_SOCK_OPS_NEEDS_ECN;
strncpy(name, optval, min_t(long, optlen,
TCP_CA_NAME_MAX-1));
name[TCP_CA_NAME_MAX-1] = 0;
ret = tcp_set_congestion_control(sk, name, false,
reinit);
} else {
struct tcp_sock *tp = tcp_sk(sk);
if (optlen != sizeof(int))
return -EINVAL;
val = *((int *)optval);
/* Only some options are supported */
switch (optname) {
case TCP_BPF_IW:
if (val <= 0 || tp->data_segs_out > 0)
ret = -EINVAL;
else
tp->snd_cwnd = val;
break;
case TCP_BPF_SNDCWND_CLAMP:
if (val <= 0) {
ret = -EINVAL;
} else {
tp->snd_cwnd_clamp = val;
tp->snd_ssthresh = val;
}
break;
default:
ret = -EINVAL;
}
}
#endif
} else {
ret = -EINVAL;
}
return ret;
}
static const struct bpf_func_proto bpf_setsockopt_proto = {
.func = bpf_setsockopt,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_PTR_TO_MEM,
.arg5_type = ARG_CONST_SIZE,
};
BPF_CALL_5(bpf_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
int, level, int, optname, char *, optval, int, optlen)
{
struct sock *sk = bpf_sock->sk;
if (!sk_fullsock(sk))
goto err_clear;
#ifdef CONFIG_INET
if (level == SOL_TCP && sk->sk_prot->getsockopt == tcp_getsockopt) {
if (optname == TCP_CONGESTION) {
struct inet_connection_sock *icsk = inet_csk(sk);
if (!icsk->icsk_ca_ops || optlen <= 1)
goto err_clear;
strncpy(optval, icsk->icsk_ca_ops->name, optlen);
optval[optlen - 1] = 0;
} else {
goto err_clear;
}
} else if (level == SOL_IP) {
struct inet_sock *inet = inet_sk(sk);
if (optlen != sizeof(int) || sk->sk_family != AF_INET)
goto err_clear;
/* Only some options are supported */
switch (optname) {
case IP_TOS:
*((int *)optval) = (int)inet->tos;
break;
default:
goto err_clear;
}
#if IS_ENABLED(CONFIG_IPV6)
} else if (level == SOL_IPV6) {
struct ipv6_pinfo *np = inet6_sk(sk);
if (optlen != sizeof(int) || sk->sk_family != AF_INET6)
goto err_clear;
/* Only some options are supported */
switch (optname) {
case IPV6_TCLASS:
*((int *)optval) = (int)np->tclass;
break;
default:
goto err_clear;
}
#endif
} else {
goto err_clear;
}
return 0;
#endif
err_clear:
memset(optval, 0, optlen);
return -EINVAL;
}
static const struct bpf_func_proto bpf_getsockopt_proto = {
.func = bpf_getsockopt,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
.arg4_type = ARG_PTR_TO_UNINIT_MEM,
.arg5_type = ARG_CONST_SIZE,
};
BPF_CALL_2(bpf_sock_ops_cb_flags_set, struct bpf_sock_ops_kern *, bpf_sock,
int, argval)
{
struct sock *sk = bpf_sock->sk;
int val = argval & BPF_SOCK_OPS_ALL_CB_FLAGS;
if (!IS_ENABLED(CONFIG_INET) || !sk_fullsock(sk))
return -EINVAL;
if (val)
tcp_sk(sk)->bpf_sock_ops_cb_flags = val;
return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS);
}
static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = {
.func = bpf_sock_ops_cb_flags_set,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
};
const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly;
EXPORT_SYMBOL_GPL(ipv6_bpf_stub);
BPF_CALL_3(bpf_bind, struct bpf_sock_addr_kern *, ctx, struct sockaddr *, addr,
int, addr_len)
{
#ifdef CONFIG_INET
struct sock *sk = ctx->sk;
int err;
/* Binding to port can be expensive so it's prohibited in the helper.
* Only binding to IP is supported.
*/
err = -EINVAL;
if (addr->sa_family == AF_INET) {
if (addr_len < sizeof(struct sockaddr_in))
return err;
if (((struct sockaddr_in *)addr)->sin_port != htons(0))
return err;
return __inet_bind(sk, addr, addr_len, true, false);
#if IS_ENABLED(CONFIG_IPV6)
} else if (addr->sa_family == AF_INET6) {
if (addr_len < SIN6_LEN_RFC2133)
return err;
if (((struct sockaddr_in6 *)addr)->sin6_port != htons(0))
return err;
/* ipv6_bpf_stub cannot be NULL, since it's called from
* bpf_cgroup_inet6_connect hook and ipv6 is already loaded
*/
return ipv6_bpf_stub->inet6_bind(sk, addr, addr_len, true, false);
#endif /* CONFIG_IPV6 */
}
#endif /* CONFIG_INET */
return -EAFNOSUPPORT;
}
static const struct bpf_func_proto bpf_bind_proto = {
.func = bpf_bind,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_PTR_TO_MEM,
.arg3_type = ARG_CONST_SIZE,
};
#ifdef CONFIG_XFRM
BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index,
struct bpf_xfrm_state *, to, u32, size, u64, flags)
{
const struct sec_path *sp = skb_sec_path(skb);
const struct xfrm_state *x;
if (!sp || unlikely(index >= sp->len || flags))
goto err_clear;
x = sp->xvec[index];
if (unlikely(size != sizeof(struct bpf_xfrm_state)))
goto err_clear;
to->reqid = x->props.reqid;
to->spi = x->id.spi;
to->family = x->props.family;
to->ext = 0;
if (to->family == AF_INET6) {
memcpy(to->remote_ipv6, x->props.saddr.a6,
sizeof(to->remote_ipv6));
} else {
to->remote_ipv4 = x->props.saddr.a4;
memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
}
return 0;
err_clear:
memset(to, 0, size);
return -EINVAL;
}
static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = {
.func = bpf_skb_get_xfrm_state,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_PTR_TO_UNINIT_MEM,
.arg4_type = ARG_CONST_SIZE,
.arg5_type = ARG_ANYTHING,
};
#endif
#if IS_ENABLED(CONFIG_INET) || IS_ENABLED(CONFIG_IPV6)
static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params,
const struct neighbour *neigh,
const struct net_device *dev)
{
memcpy(params->dmac, neigh->ha, ETH_ALEN);
memcpy(params->smac, dev->dev_addr, ETH_ALEN);
params->h_vlan_TCI = 0;
params->h_vlan_proto = 0;
params->ifindex = dev->ifindex;
return 0;
}
#endif
#if IS_ENABLED(CONFIG_INET)
static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
u32 flags, bool check_mtu)
{
struct in_device *in_dev;
struct neighbour *neigh;
struct net_device *dev;
struct fib_result res;
struct fib_nh *nh;
struct flowi4 fl4;
int err;
u32 mtu;
dev = dev_get_by_index_rcu(net, params->ifindex);
if (unlikely(!dev))
return -ENODEV;
/* verify forwarding is enabled on this interface */
in_dev = __in_dev_get_rcu(dev);
if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev)))
return BPF_FIB_LKUP_RET_FWD_DISABLED;
if (flags & BPF_FIB_LOOKUP_OUTPUT) {
fl4.flowi4_iif = 1;
fl4.flowi4_oif = params->ifindex;
} else {
fl4.flowi4_iif = params->ifindex;
fl4.flowi4_oif = 0;
}
fl4.flowi4_tos = params->tos & IPTOS_RT_MASK;
fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
fl4.flowi4_flags = 0;
fl4.flowi4_proto = params->l4_protocol;
fl4.daddr = params->ipv4_dst;
fl4.saddr = params->ipv4_src;
fl4.fl4_sport = params->sport;
fl4.fl4_dport = params->dport;
if (flags & BPF_FIB_LOOKUP_DIRECT) {
u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
struct fib_table *tb;
tb = fib_get_table(net, tbid);
if (unlikely(!tb))
return BPF_FIB_LKUP_RET_NOT_FWDED;
err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
} else {
fl4.flowi4_mark = 0;
fl4.flowi4_secid = 0;
fl4.flowi4_tun_key.tun_id = 0;
fl4.flowi4_uid = sock_net_uid(net, NULL);
err = fib_lookup(net, &fl4, &res, FIB_LOOKUP_NOREF);
}
if (err) {
/* map fib lookup errors to RTN_ type */
if (err == -EINVAL)
return BPF_FIB_LKUP_RET_BLACKHOLE;
if (err == -EHOSTUNREACH)
return BPF_FIB_LKUP_RET_UNREACHABLE;
if (err == -EACCES)
return BPF_FIB_LKUP_RET_PROHIBIT;
return BPF_FIB_LKUP_RET_NOT_FWDED;
}
if (res.type != RTN_UNICAST)
return BPF_FIB_LKUP_RET_NOT_FWDED;
if (res.fi->fib_nhs > 1)
fib_select_path(net, &res, &fl4, NULL);
if (check_mtu) {
mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst);
if (params->tot_len > mtu)
return BPF_FIB_LKUP_RET_FRAG_NEEDED;
}
nh = &res.fi->fib_nh[res.nh_sel];
/* do not handle lwt encaps right now */
if (nh->nh_lwtstate)
return BPF_FIB_LKUP_RET_UNSUPP_LWT;
dev = nh->nh_dev;
if (nh->nh_gw)
params->ipv4_dst = nh->nh_gw;
params->rt_metric = res.fi->fib_priority;
/* xdp and cls_bpf programs are run in RCU-bh so
* rcu_read_lock_bh is not needed here
*/
neigh = __ipv4_neigh_lookup_noref(dev, (__force u32)params->ipv4_dst);
if (!neigh)
return BPF_FIB_LKUP_RET_NO_NEIGH;
return bpf_fib_set_fwd_params(params, neigh, dev);
}
#endif
#if IS_ENABLED(CONFIG_IPV6)
static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
u32 flags, bool check_mtu)
{
struct in6_addr *src = (struct in6_addr *) params->ipv6_src;
struct in6_addr *dst = (struct in6_addr *) params->ipv6_dst;
struct neighbour *neigh;
struct net_device *dev;
struct inet6_dev *idev;
struct fib6_info *f6i;
struct flowi6 fl6;
int strict = 0;
int oif;
u32 mtu;
/* link local addresses are never forwarded */
if (rt6_need_strict(dst) || rt6_need_strict(src))
return BPF_FIB_LKUP_RET_NOT_FWDED;
dev = dev_get_by_index_rcu(net, params->ifindex);
if (unlikely(!dev))
return -ENODEV;
idev = __in6_dev_get_safely(dev);
if (unlikely(!idev || !net->ipv6.devconf_all->forwarding))
return BPF_FIB_LKUP_RET_FWD_DISABLED;
if (flags & BPF_FIB_LOOKUP_OUTPUT) {
fl6.flowi6_iif = 1;
oif = fl6.flowi6_oif = params->ifindex;
} else {
oif = fl6.flowi6_iif = params->ifindex;
fl6.flowi6_oif = 0;
strict = RT6_LOOKUP_F_HAS_SADDR;
}
fl6.flowlabel = params->flowinfo;
fl6.flowi6_scope = 0;
fl6.flowi6_flags = 0;
fl6.mp_hash = 0;
fl6.flowi6_proto = params->l4_protocol;
fl6.daddr = *dst;
fl6.saddr = *src;
fl6.fl6_sport = params->sport;
fl6.fl6_dport = params->dport;
if (flags & BPF_FIB_LOOKUP_DIRECT) {
u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
struct fib6_table *tb;
tb = ipv6_stub->fib6_get_table(net, tbid);
if (unlikely(!tb))
return BPF_FIB_LKUP_RET_NOT_FWDED;
f6i = ipv6_stub->fib6_table_lookup(net, tb, oif, &fl6, strict);
} else {
fl6.flowi6_mark = 0;
fl6.flowi6_secid = 0;
fl6.flowi6_tun_key.tun_id = 0;
fl6.flowi6_uid = sock_net_uid(net, NULL);
f6i = ipv6_stub->fib6_lookup(net, oif, &fl6, strict);
}
if (unlikely(IS_ERR_OR_NULL(f6i) || f6i == net->ipv6.fib6_null_entry))
return BPF_FIB_LKUP_RET_NOT_FWDED;
if (unlikely(f6i->fib6_flags & RTF_REJECT)) {
switch (f6i->fib6_type) {
case RTN_BLACKHOLE:
return BPF_FIB_LKUP_RET_BLACKHOLE;
case RTN_UNREACHABLE:
return BPF_FIB_LKUP_RET_UNREACHABLE;
case RTN_PROHIBIT:
return BPF_FIB_LKUP_RET_PROHIBIT;
default:
return BPF_FIB_LKUP_RET_NOT_FWDED;
}
}
if (f6i->fib6_type != RTN_UNICAST)
return BPF_FIB_LKUP_RET_NOT_FWDED;
if (f6i->fib6_nsiblings && fl6.flowi6_oif == 0)
f6i = ipv6_stub->fib6_multipath_select(net, f6i, &fl6,
fl6.flowi6_oif, NULL,
strict);
if (check_mtu) {
mtu = ipv6_stub->ip6_mtu_from_fib6(f6i, dst, src);
if (params->tot_len > mtu)
return BPF_FIB_LKUP_RET_FRAG_NEEDED;
}
if (f6i->fib6_nh.nh_lwtstate)
return BPF_FIB_LKUP_RET_UNSUPP_LWT;
if (f6i->fib6_flags & RTF_GATEWAY)
*dst = f6i->fib6_nh.nh_gw;
dev = f6i->fib6_nh.nh_dev;
params->rt_metric = f6i->fib6_metric;
/* xdp and cls_bpf programs are run in RCU-bh so rcu_read_lock_bh is
* not needed here. Can not use __ipv6_neigh_lookup_noref here
* because we need to get nd_tbl via the stub
*/
neigh = ___neigh_lookup_noref(ipv6_stub->nd_tbl, neigh_key_eq128,
ndisc_hashfn, dst, dev);
if (!neigh)
return BPF_FIB_LKUP_RET_NO_NEIGH;
return bpf_fib_set_fwd_params(params, neigh, dev);
}
#endif
BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx,
struct bpf_fib_lookup *, params, int, plen, u32, flags)
{
if (plen < sizeof(*params))
return -EINVAL;
if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT))
return -EINVAL;
switch (params->family) {
#if IS_ENABLED(CONFIG_INET)
case AF_INET:
return bpf_ipv4_fib_lookup(dev_net(ctx->rxq->dev), params,
flags, true);
#endif
#if IS_ENABLED(CONFIG_IPV6)
case AF_INET6:
return bpf_ipv6_fib_lookup(dev_net(ctx->rxq->dev), params,
flags, true);
#endif
}
return -EAFNOSUPPORT;
}
static const struct bpf_func_proto bpf_xdp_fib_lookup_proto = {
.func = bpf_xdp_fib_lookup,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_PTR_TO_MEM,
.arg3_type = ARG_CONST_SIZE,
.arg4_type = ARG_ANYTHING,
};
BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb,
struct bpf_fib_lookup *, params, int, plen, u32, flags)
{
struct net *net = dev_net(skb->dev);
int rc = -EAFNOSUPPORT;
if (plen < sizeof(*params))
return -EINVAL;
if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT))
return -EINVAL;
switch (params->family) {
#if IS_ENABLED(CONFIG_INET)
case AF_INET:
rc = bpf_ipv4_fib_lookup(net, params, flags, false);
break;
#endif
#if IS_ENABLED(CONFIG_IPV6)
case AF_INET6:
rc = bpf_ipv6_fib_lookup(net, params, flags, false);
break;
#endif
}
if (!rc) {
struct net_device *dev;
dev = dev_get_by_index_rcu(net, params->ifindex);
if (!is_skb_forwardable(dev, skb))
rc = BPF_FIB_LKUP_RET_FRAG_NEEDED;
}
return rc;
}
static const struct bpf_func_proto bpf_skb_fib_lookup_proto = {
.func = bpf_skb_fib_lookup,
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_PTR_TO_MEM,
.arg3_type = ARG_CONST_SIZE,
.arg4_type = ARG_ANYTHING,
};
#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
{
int err;
struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr;
if (!seg6_validate_srh(srh, len))
return -EINVAL;
switch (type) {
case BPF_LWT_ENCAP_SEG6_INLINE:
if (skb->protocol != htons(ETH_P_IPV6))
return -EBADMSG;
err = seg6_do_srh_inline(skb, srh);
break;
case BPF_LWT_ENCAP_SEG6:
skb_reset_inner_headers(skb);
skb->encapsulation = 1;
err = seg6_do_srh_encap(skb, srh, IPPROTO_IPV6);
break;
default:
return -EINVAL;
}
bpf_compute_data_pointers(skb);
if (err)
return err;
ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
skb_set_transport_header(skb, sizeof(struct ipv6hdr));
return seg6_lookup_nexthop(skb, NULL, 0);
}
#endif /* CONFIG_IPV6_SEG6_BPF */
BPF_CALL_4(bpf_lwt_push_encap, struct sk_buff *, skb, u32, type, void *, hdr,
u32, len)
{
switch (type) {
#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
case BPF_LWT_ENCAP_SEG6:
case BPF_LWT_ENCAP_SEG6_INLINE:
return bpf_push_seg6_encap(skb, type, hdr, len);
#endif
default:
return -EINVAL;
}
}
static const struct bpf_func_proto bpf_lwt_push_encap_proto = {
.func = bpf_lwt_push_encap,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_PTR_TO_MEM,
.arg4_type = ARG_CONST_SIZE
};
#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset,
const void *, from, u32, len)
{
struct seg6_bpf_srh_state *srh_state =
this_cpu_ptr(&seg6_bpf_srh_states);
struct ipv6_sr_hdr *srh = srh_state->srh;
void *srh_tlvs, *srh_end, *ptr;
int srhoff = 0;
if (srh == NULL)
return -EINVAL;
srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4));
srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen);
ptr = skb->data + offset;
if (ptr >= srh_tlvs && ptr + len <= srh_end)
srh_state->valid = false;
else if (ptr < (void *)&srh->flags ||
ptr + len > (void *)&srh->segments)
return -EFAULT;
if (unlikely(bpf_try_make_writable(skb, offset + len)))
return -EFAULT;
if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
return -EINVAL;
srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
memcpy(skb->data + offset, from, len);
return 0;
}
static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = {
.func = bpf_lwt_seg6_store_bytes,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_PTR_TO_MEM,
.arg4_type = ARG_CONST_SIZE
};
static void bpf_update_srh_state(struct sk_buff *skb)
{
struct seg6_bpf_srh_state *srh_state =
this_cpu_ptr(&seg6_bpf_srh_states);
int srhoff = 0;
if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) {
srh_state->srh = NULL;
} else {
srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
srh_state->hdrlen = srh_state->srh->hdrlen << 3;
srh_state->valid = true;
}
}
BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb,
u32, action, void *, param, u32, param_len)
{
struct seg6_bpf_srh_state *srh_state =
this_cpu_ptr(&seg6_bpf_srh_states);
int hdroff = 0;
int err;
switch (action) {
case SEG6_LOCAL_ACTION_END_X:
if (!seg6_bpf_has_valid_srh(skb))
return -EBADMSG;
if (param_len != sizeof(struct in6_addr))
return -EINVAL;
return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0);
case SEG6_LOCAL_ACTION_END_T:
if (!seg6_bpf_has_valid_srh(skb))
return -EBADMSG;
if (param_len != sizeof(int))
return -EINVAL;
return seg6_lookup_nexthop(skb, NULL, *(int *)param);
case SEG6_LOCAL_ACTION_END_DT6:
if (!seg6_bpf_has_valid_srh(skb))
return -EBADMSG;
if (param_len != sizeof(int))
return -EINVAL;
if (ipv6_find_hdr(skb, &hdroff, IPPROTO_IPV6, NULL, NULL) < 0)
return -EBADMSG;
if (!pskb_pull(skb, hdroff))
return -EBADMSG;
skb_postpull_rcsum(skb, skb_network_header(skb), hdroff);
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
skb->encapsulation = 0;
bpf_compute_data_pointers(skb);
bpf_update_srh_state(skb);
return seg6_lookup_nexthop(skb, NULL, *(int *)param);
case SEG6_LOCAL_ACTION_END_B6:
if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
return -EBADMSG;
err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE,
param, param_len);
if (!err)
bpf_update_srh_state(skb);
return err;
case SEG6_LOCAL_ACTION_END_B6_ENCAP:
if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
return -EBADMSG;
err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6,
param, param_len);
if (!err)
bpf_update_srh_state(skb);
return err;
default:
return -EINVAL;
}
}
static const struct bpf_func_proto bpf_lwt_seg6_action_proto = {
.func = bpf_lwt_seg6_action,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_PTR_TO_MEM,
.arg4_type = ARG_CONST_SIZE
};
BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset,
s32, len)
{
struct seg6_bpf_srh_state *srh_state =
this_cpu_ptr(&seg6_bpf_srh_states);
struct ipv6_sr_hdr *srh = srh_state->srh;
void *srh_end, *srh_tlvs, *ptr;
struct ipv6hdr *hdr;
int srhoff = 0;
int ret;
if (unlikely(srh == NULL))
return -EINVAL;
srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) +
((srh->first_segment + 1) << 4));
srh_end = (void *)((unsigned char *)srh + sizeof(*srh) +
srh_state->hdrlen);
ptr = skb->data + offset;
if (unlikely(ptr < srh_tlvs || ptr > srh_end))
return -EFAULT;
if (unlikely(len < 0 && (void *)((char *)ptr - len) > srh_end))
return -EFAULT;
if (len > 0) {
ret = skb_cow_head(skb, len);
if (unlikely(ret < 0))
return ret;
ret = bpf_skb_net_hdr_push(skb, offset, len);
} else {
ret = bpf_skb_net_hdr_pop(skb, offset, -1 * len);
}
bpf_compute_data_pointers(skb);
if (unlikely(ret < 0))
return ret;
hdr = (struct ipv6hdr *)skb->data;
hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
return -EINVAL;
srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
srh_state->hdrlen += len;
srh_state->valid = false;
return 0;
}
static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = {
.func = bpf_lwt_seg6_adjust_srh,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_ANYTHING,
};
#endif /* CONFIG_IPV6_SEG6_BPF */
bool bpf_helper_changes_pkt_data(void *func)
{
if (func == bpf_skb_vlan_push ||
func == bpf_skb_vlan_pop ||
func == bpf_skb_store_bytes ||
func == bpf_skb_change_proto ||
func == bpf_skb_change_head ||
func == sk_skb_change_head ||
func == bpf_skb_change_tail ||
func == sk_skb_change_tail ||
func == bpf_skb_adjust_room ||
func == bpf_skb_pull_data ||
func == sk_skb_pull_data ||
func == bpf_clone_redirect ||
func == bpf_l3_csum_replace ||
func == bpf_l4_csum_replace ||
func == bpf_xdp_adjust_head ||
func == bpf_xdp_adjust_meta ||
func == bpf_msg_pull_data ||
func == bpf_xdp_adjust_tail ||
#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
func == bpf_lwt_seg6_store_bytes ||
func == bpf_lwt_seg6_adjust_srh ||
func == bpf_lwt_seg6_action ||
#endif
func == bpf_lwt_push_encap)
return true;
return false;
}
static const struct bpf_func_proto *
bpf_base_func_proto(enum bpf_func_id func_id)
{
switch (func_id) {
case BPF_FUNC_map_lookup_elem:
return &bpf_map_lookup_elem_proto;
case BPF_FUNC_map_update_elem:
return &bpf_map_update_elem_proto;
case BPF_FUNC_map_delete_elem:
return &bpf_map_delete_elem_proto;
case BPF_FUNC_get_prandom_u32:
return &bpf_get_prandom_u32_proto;
case BPF_FUNC_get_smp_processor_id:
return &bpf_get_raw_smp_processor_id_proto;
case BPF_FUNC_get_numa_node_id:
return &bpf_get_numa_node_id_proto;
case BPF_FUNC_tail_call:
return &bpf_tail_call_proto;
case BPF_FUNC_ktime_get_ns:
return &bpf_ktime_get_ns_proto;
case BPF_FUNC_trace_printk:
if (capable(CAP_SYS_ADMIN))
return bpf_get_trace_printk_proto();
/* else: fall through */
default:
return NULL;
}
}
static const struct bpf_func_proto *
sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
/* inet and inet6 sockets are created in a process
* context so there is always a valid uid/gid
*/
case BPF_FUNC_get_current_uid_gid:
return &bpf_get_current_uid_gid_proto;
case BPF_FUNC_get_local_storage:
return &bpf_get_local_storage_proto;
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
/* inet and inet6 sockets are created in a process
* context so there is always a valid uid/gid
*/
case BPF_FUNC_get_current_uid_gid:
return &bpf_get_current_uid_gid_proto;
case BPF_FUNC_bind:
switch (prog->expected_attach_type) {
case BPF_CGROUP_INET4_CONNECT:
case BPF_CGROUP_INET6_CONNECT:
return &bpf_bind_proto;
default:
return NULL;
}
case BPF_FUNC_get_socket_cookie:
return &bpf_get_socket_cookie_sock_addr_proto;
case BPF_FUNC_get_local_storage:
return &bpf_get_local_storage_proto;
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_skb_load_bytes:
return &bpf_skb_load_bytes_proto;
case BPF_FUNC_skb_load_bytes_relative:
return &bpf_skb_load_bytes_relative_proto;
case BPF_FUNC_get_socket_cookie:
return &bpf_get_socket_cookie_proto;
case BPF_FUNC_get_socket_uid:
return &bpf_get_socket_uid_proto;
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_get_local_storage:
return &bpf_get_local_storage_proto;
default:
return sk_filter_func_proto(func_id, prog);
}
}
static const struct bpf_func_proto *
tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_skb_store_bytes:
return &bpf_skb_store_bytes_proto;
case BPF_FUNC_skb_load_bytes:
return &bpf_skb_load_bytes_proto;
case BPF_FUNC_skb_load_bytes_relative:
return &bpf_skb_load_bytes_relative_proto;
case BPF_FUNC_skb_pull_data:
return &bpf_skb_pull_data_proto;
case BPF_FUNC_csum_diff:
return &bpf_csum_diff_proto;
case BPF_FUNC_csum_update:
return &bpf_csum_update_proto;
case BPF_FUNC_l3_csum_replace:
return &bpf_l3_csum_replace_proto;
case BPF_FUNC_l4_csum_replace:
return &bpf_l4_csum_replace_proto;
case BPF_FUNC_clone_redirect:
return &bpf_clone_redirect_proto;
case BPF_FUNC_get_cgroup_classid:
return &bpf_get_cgroup_classid_proto;
case BPF_FUNC_skb_vlan_push:
return &bpf_skb_vlan_push_proto;
case BPF_FUNC_skb_vlan_pop:
return &bpf_skb_vlan_pop_proto;
case BPF_FUNC_skb_change_proto:
return &bpf_skb_change_proto_proto;
case BPF_FUNC_skb_change_type:
return &bpf_skb_change_type_proto;
case BPF_FUNC_skb_adjust_room:
return &bpf_skb_adjust_room_proto;
case BPF_FUNC_skb_change_tail:
return &bpf_skb_change_tail_proto;
case BPF_FUNC_skb_get_tunnel_key:
return &bpf_skb_get_tunnel_key_proto;
case BPF_FUNC_skb_set_tunnel_key:
return bpf_get_skb_set_tunnel_proto(func_id);
case BPF_FUNC_skb_get_tunnel_opt:
return &bpf_skb_get_tunnel_opt_proto;
case BPF_FUNC_skb_set_tunnel_opt:
return bpf_get_skb_set_tunnel_proto(func_id);
case BPF_FUNC_redirect:
return &bpf_redirect_proto;
case BPF_FUNC_get_route_realm:
return &bpf_get_route_realm_proto;
case BPF_FUNC_get_hash_recalc:
return &bpf_get_hash_recalc_proto;
case BPF_FUNC_set_hash_invalid:
return &bpf_set_hash_invalid_proto;
case BPF_FUNC_set_hash:
return &bpf_set_hash_proto;
case BPF_FUNC_perf_event_output:
return &bpf_skb_event_output_proto;
case BPF_FUNC_get_smp_processor_id:
return &bpf_get_smp_processor_id_proto;
case BPF_FUNC_skb_under_cgroup:
return &bpf_skb_under_cgroup_proto;
case BPF_FUNC_get_socket_cookie:
return &bpf_get_socket_cookie_proto;
case BPF_FUNC_get_socket_uid:
return &bpf_get_socket_uid_proto;
case BPF_FUNC_fib_lookup:
return &bpf_skb_fib_lookup_proto;
#ifdef CONFIG_XFRM
case BPF_FUNC_skb_get_xfrm_state:
return &bpf_skb_get_xfrm_state_proto;
#endif
#ifdef CONFIG_SOCK_CGROUP_DATA
case BPF_FUNC_skb_cgroup_id:
return &bpf_skb_cgroup_id_proto;
#endif
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_perf_event_output:
return &bpf_xdp_event_output_proto;
case BPF_FUNC_get_smp_processor_id:
return &bpf_get_smp_processor_id_proto;
case BPF_FUNC_csum_diff:
return &bpf_csum_diff_proto;
case BPF_FUNC_xdp_adjust_head:
return &bpf_xdp_adjust_head_proto;
case BPF_FUNC_xdp_adjust_meta:
return &bpf_xdp_adjust_meta_proto;
case BPF_FUNC_redirect:
return &bpf_xdp_redirect_proto;
case BPF_FUNC_redirect_map:
return &bpf_xdp_redirect_map_proto;
case BPF_FUNC_xdp_adjust_tail:
return &bpf_xdp_adjust_tail_proto;
case BPF_FUNC_fib_lookup:
return &bpf_xdp_fib_lookup_proto;
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_setsockopt:
return &bpf_setsockopt_proto;
case BPF_FUNC_getsockopt:
return &bpf_getsockopt_proto;
case BPF_FUNC_sock_ops_cb_flags_set:
return &bpf_sock_ops_cb_flags_set_proto;
case BPF_FUNC_sock_map_update:
return &bpf_sock_map_update_proto;
case BPF_FUNC_sock_hash_update:
return &bpf_sock_hash_update_proto;
case BPF_FUNC_get_socket_cookie:
return &bpf_get_socket_cookie_sock_ops_proto;
case BPF_FUNC_get_local_storage:
return &bpf_get_local_storage_proto;
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_msg_redirect_map:
return &bpf_msg_redirect_map_proto;
case BPF_FUNC_msg_redirect_hash:
return &bpf_msg_redirect_hash_proto;
case BPF_FUNC_msg_apply_bytes:
return &bpf_msg_apply_bytes_proto;
case BPF_FUNC_msg_cork_bytes:
return &bpf_msg_cork_bytes_proto;
case BPF_FUNC_msg_pull_data:
return &bpf_msg_pull_data_proto;
case BPF_FUNC_get_local_storage:
return &bpf_get_local_storage_proto;
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_skb_store_bytes:
return &bpf_skb_store_bytes_proto;
case BPF_FUNC_skb_load_bytes:
return &bpf_skb_load_bytes_proto;
case BPF_FUNC_skb_pull_data:
return &sk_skb_pull_data_proto;
case BPF_FUNC_skb_change_tail:
return &sk_skb_change_tail_proto;
case BPF_FUNC_skb_change_head:
return &sk_skb_change_head_proto;
case BPF_FUNC_get_socket_cookie:
return &bpf_get_socket_cookie_proto;
case BPF_FUNC_get_socket_uid:
return &bpf_get_socket_uid_proto;
case BPF_FUNC_sk_redirect_map:
return &bpf_sk_redirect_map_proto;
case BPF_FUNC_sk_redirect_hash:
return &bpf_sk_redirect_hash_proto;
case BPF_FUNC_get_local_storage:
return &bpf_get_local_storage_proto;
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
lwt_out_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_skb_load_bytes:
return &bpf_skb_load_bytes_proto;
case BPF_FUNC_skb_pull_data:
return &bpf_skb_pull_data_proto;
case BPF_FUNC_csum_diff:
return &bpf_csum_diff_proto;
case BPF_FUNC_get_cgroup_classid:
return &bpf_get_cgroup_classid_proto;
case BPF_FUNC_get_route_realm:
return &bpf_get_route_realm_proto;
case BPF_FUNC_get_hash_recalc:
return &bpf_get_hash_recalc_proto;
case BPF_FUNC_perf_event_output:
return &bpf_skb_event_output_proto;
case BPF_FUNC_get_smp_processor_id:
return &bpf_get_smp_processor_id_proto;
case BPF_FUNC_skb_under_cgroup:
return &bpf_skb_under_cgroup_proto;
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
lwt_in_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_lwt_push_encap:
return &bpf_lwt_push_encap_proto;
default:
return lwt_out_func_proto(func_id, prog);
}
}
static const struct bpf_func_proto *
lwt_xmit_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_skb_get_tunnel_key:
return &bpf_skb_get_tunnel_key_proto;
case BPF_FUNC_skb_set_tunnel_key:
return bpf_get_skb_set_tunnel_proto(func_id);
case BPF_FUNC_skb_get_tunnel_opt:
return &bpf_skb_get_tunnel_opt_proto;
case BPF_FUNC_skb_set_tunnel_opt:
return bpf_get_skb_set_tunnel_proto(func_id);
case BPF_FUNC_redirect:
return &bpf_redirect_proto;
case BPF_FUNC_clone_redirect:
return &bpf_clone_redirect_proto;
case BPF_FUNC_skb_change_tail:
return &bpf_skb_change_tail_proto;
case BPF_FUNC_skb_change_head:
return &bpf_skb_change_head_proto;
case BPF_FUNC_skb_store_bytes:
return &bpf_skb_store_bytes_proto;
case BPF_FUNC_csum_update:
return &bpf_csum_update_proto;
case BPF_FUNC_l3_csum_replace:
return &bpf_l3_csum_replace_proto;
case BPF_FUNC_l4_csum_replace:
return &bpf_l4_csum_replace_proto;
case BPF_FUNC_set_hash_invalid:
return &bpf_set_hash_invalid_proto;
default:
return lwt_out_func_proto(func_id, prog);
}
}
static const struct bpf_func_proto *
lwt_seg6local_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
#if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
case BPF_FUNC_lwt_seg6_store_bytes:
return &bpf_lwt_seg6_store_bytes_proto;
case BPF_FUNC_lwt_seg6_action:
return &bpf_lwt_seg6_action_proto;
case BPF_FUNC_lwt_seg6_adjust_srh:
return &bpf_lwt_seg6_adjust_srh_proto;
#endif
default:
return lwt_out_func_proto(func_id, prog);
}
}
static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
const int size_default = sizeof(__u32);
if (off < 0 || off >= sizeof(struct __sk_buff))
return false;
/* The verifier guarantees that size > 0. */
if (off % size != 0)
return false;
switch (off) {
case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
if (off + size > offsetofend(struct __sk_buff, cb[4]))
return false;
break;
case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]):
case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]):
case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4):
case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4):
case bpf_ctx_range(struct __sk_buff, data):
case bpf_ctx_range(struct __sk_buff, data_meta):
case bpf_ctx_range(struct __sk_buff, data_end):
if (size != size_default)
return false;
break;
default:
/* Only narrow read access allowed for now. */
if (type == BPF_WRITE) {
if (size != size_default)
return false;
} else {
bpf_ctx_record_field_size(info, size_default);
if (!bpf_ctx_narrow_access_ok(off, size, size_default))
return false;
}
}
return true;
}
static bool sk_filter_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
switch (off) {
case bpf_ctx_range(struct __sk_buff, tc_classid):
case bpf_ctx_range(struct __sk_buff, data):
case bpf_ctx_range(struct __sk_buff, data_meta):
case bpf_ctx_range(struct __sk_buff, data_end):
case bpf_ctx_range_till(struct __sk_buff, family, local_port):
return false;
}
if (type == BPF_WRITE) {
switch (off) {
case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
break;
default:
return false;
}
}
return bpf_skb_is_valid_access(off, size, type, prog, info);
}
static bool lwt_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
switch (off) {
case bpf_ctx_range(struct __sk_buff, tc_classid):
case bpf_ctx_range_till(struct __sk_buff, family, local_port):
case bpf_ctx_range(struct __sk_buff, data_meta):
return false;
}
if (type == BPF_WRITE) {
switch (off) {
case bpf_ctx_range(struct __sk_buff, mark):
case bpf_ctx_range(struct __sk_buff, priority):
case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
break;
default:
return false;
}
}
switch (off) {
case bpf_ctx_range(struct __sk_buff, data):
info->reg_type = PTR_TO_PACKET;
break;
case bpf_ctx_range(struct __sk_buff, data_end):
info->reg_type = PTR_TO_PACKET_END;
break;
}
return bpf_skb_is_valid_access(off, size, type, prog, info);
}
/* Attach type specific accesses */
static bool __sock_filter_check_attach_type(int off,
enum bpf_access_type access_type,
enum bpf_attach_type attach_type)
{
switch (off) {
case offsetof(struct bpf_sock, bound_dev_if):
case offsetof(struct bpf_sock, mark):
case offsetof(struct bpf_sock, priority):
switch (attach_type) {
case BPF_CGROUP_INET_SOCK_CREATE:
goto full_access;
default:
return false;
}
case bpf_ctx_range(struct bpf_sock, src_ip4):
switch (attach_type) {
case BPF_CGROUP_INET4_POST_BIND:
goto read_only;
default:
return false;
}
case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
switch (attach_type) {
case BPF_CGROUP_INET6_POST_BIND:
goto read_only;
default:
return false;
}
case bpf_ctx_range(struct bpf_sock, src_port):
switch (attach_type) {
case BPF_CGROUP_INET4_POST_BIND:
case BPF_CGROUP_INET6_POST_BIND:
goto read_only;
default:
return false;
}
}
read_only:
return access_type == BPF_READ;
full_access:
return true;
}
static bool __sock_filter_check_size(int off, int size,
struct bpf_insn_access_aux *info)
{
const int size_default = sizeof(__u32);
switch (off) {
case bpf_ctx_range(struct bpf_sock, src_ip4):
case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
bpf_ctx_record_field_size(info, size_default);
return bpf_ctx_narrow_access_ok(off, size, size_default);
}
return size == size_default;
}
static bool sock_filter_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
if (off < 0 || off >= sizeof(struct bpf_sock))
return false;
if (off % size != 0)
return false;
if (!__sock_filter_check_attach_type(off, type,
prog->expected_attach_type))
return false;
if (!__sock_filter_check_size(off, size, info))
return false;
return true;
}
static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
const struct bpf_prog *prog, int drop_verdict)
{
struct bpf_insn *insn = insn_buf;
if (!direct_write)
return 0;
/* if (!skb->cloned)
* goto start;
*
* (Fast-path, otherwise approximation that we might be
* a clone, do the rest in helper.)
*/
*insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET());
*insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
*insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);
/* ret = bpf_skb_pull_data(skb, 0); */
*insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
*insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
*insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_skb_pull_data);
/* if (!ret)
* goto restore;
* return TC_ACT_SHOT;
*/
*insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
*insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
*insn++ = BPF_EXIT_INSN();
/* restore: */
*insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
/* start: */
*insn++ = prog->insnsi[0];
return insn - insn_buf;
}
static int bpf_gen_ld_abs(const struct bpf_insn *orig,
struct bpf_insn *insn_buf)
{
bool indirect = BPF_MODE(orig->code) == BPF_IND;
struct bpf_insn *insn = insn_buf;
/* We're guaranteed here that CTX is in R6. */
*insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_CTX);
if (!indirect) {
*insn++ = BPF_MOV64_IMM(BPF_REG_2, orig->imm);
} else {
*insn++ = BPF_MOV64_REG(BPF_REG_2, orig->src_reg);
if (orig->imm)
*insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, orig->imm);
}
switch (BPF_SIZE(orig->code)) {
case BPF_B:
*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8_no_cache);
break;
case BPF_H:
*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16_no_cache);
break;
case BPF_W:
*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32_no_cache);
break;
}
*insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_0, 0, 2);
*insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_0, BPF_REG_0);
*insn++ = BPF_EXIT_INSN();
return insn - insn_buf;
}
static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
const struct bpf_prog *prog)
{
return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT);
}
static bool tc_cls_act_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
if (type == BPF_WRITE) {
switch (off) {
case bpf_ctx_range(struct __sk_buff, mark):
case bpf_ctx_range(struct __sk_buff, tc_index):
case bpf_ctx_range(struct __sk_buff, priority):
case bpf_ctx_range(struct __sk_buff, tc_classid):
case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
break;
default:
return false;
}
}
switch (off) {
case bpf_ctx_range(struct __sk_buff, data):
info->reg_type = PTR_TO_PACKET;
break;
case bpf_ctx_range(struct __sk_buff, data_meta):
info->reg_type = PTR_TO_PACKET_META;
break;
case bpf_ctx_range(struct __sk_buff, data_end):
info->reg_type = PTR_TO_PACKET_END;
break;
case bpf_ctx_range_till(struct __sk_buff, family, local_port):
return false;
}
return bpf_skb_is_valid_access(off, size, type, prog, info);
}
static bool __is_valid_xdp_access(int off, int size)
{
if (off < 0 || off >= sizeof(struct xdp_md))
return false;
if (off % size != 0)
return false;
if (size != sizeof(__u32))
return false;
return true;
}
static bool xdp_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
if (type == BPF_WRITE) {
if (bpf_prog_is_dev_bound(prog->aux)) {
switch (off) {
case offsetof(struct xdp_md, rx_queue_index):
return __is_valid_xdp_access(off, size);
}
}
return false;
}
switch (off) {
case offsetof(struct xdp_md, data):
info->reg_type = PTR_TO_PACKET;
break;
case offsetof(struct xdp_md, data_meta):
info->reg_type = PTR_TO_PACKET_META;
break;
case offsetof(struct xdp_md, data_end):
info->reg_type = PTR_TO_PACKET_END;
break;
}
return __is_valid_xdp_access(off, size);
}
void bpf_warn_invalid_xdp_action(u32 act)
{
const u32 act_max = XDP_REDIRECT;
WARN_ONCE(1, "%s XDP return value %u, expect packet loss!\n",
act > act_max ? "Illegal" : "Driver unsupported",
act);
}
EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
static bool sock_addr_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
const int size_default = sizeof(__u32);
if (off < 0 || off >= sizeof(struct bpf_sock_addr))
return false;
if (off % size != 0)
return false;
/* Disallow access to IPv6 fields from IPv4 contex and vise
* versa.
*/
switch (off) {
case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
switch (prog->expected_attach_type) {
case BPF_CGROUP_INET4_BIND:
case BPF_CGROUP_INET4_CONNECT:
case BPF_CGROUP_UDP4_SENDMSG:
break;
default:
return false;
}
break;
case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
switch (prog->expected_attach_type) {
case BPF_CGROUP_INET6_BIND:
case BPF_CGROUP_INET6_CONNECT:
case BPF_CGROUP_UDP6_SENDMSG:
break;
default:
return false;
}
break;
case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
switch (prog->expected_attach_type) {
case BPF_CGROUP_UDP4_SENDMSG:
break;
default:
return false;
}
break;
case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
msg_src_ip6[3]):
switch (prog->expected_attach_type) {
case BPF_CGROUP_UDP6_SENDMSG:
break;
default:
return false;
}
break;
}
switch (off) {
case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
msg_src_ip6[3]):
/* Only narrow read access allowed for now. */
if (type == BPF_READ) {
bpf_ctx_record_field_size(info, size_default);
if (!bpf_ctx_narrow_access_ok(off, size, size_default))
return false;
} else {
if (size != size_default)
return false;
}
break;
case bpf_ctx_range(struct bpf_sock_addr, user_port):
if (size != size_default)
return false;
break;
default:
if (type == BPF_READ) {
if (size != size_default)
return false;
} else {
return false;
}
}
return true;
}
static bool sock_ops_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
const int size_default = sizeof(__u32);
if (off < 0 || off >= sizeof(struct bpf_sock_ops))
return false;
/* The verifier guarantees that size > 0. */
if (off % size != 0)
return false;
if (type == BPF_WRITE) {
switch (off) {
case offsetof(struct bpf_sock_ops, reply):
case offsetof(struct bpf_sock_ops, sk_txhash):
if (size != size_default)
return false;
break;
default:
return false;
}
} else {
switch (off) {
case bpf_ctx_range_till(struct bpf_sock_ops, bytes_received,
bytes_acked):
if (size != sizeof(__u64))
return false;
break;
default:
if (size != size_default)
return false;
break;
}
}
return true;
}
static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
const struct bpf_prog *prog)
{
return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP);
}
static bool sk_skb_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
switch (off) {
case bpf_ctx_range(struct __sk_buff, tc_classid):
case bpf_ctx_range(struct __sk_buff, data_meta):
return false;
}
if (type == BPF_WRITE) {
switch (off) {
case bpf_ctx_range(struct __sk_buff, tc_index):
case bpf_ctx_range(struct __sk_buff, priority):
break;
default:
return false;
}
}
switch (off) {
case bpf_ctx_range(struct __sk_buff, mark):
return false;
case bpf_ctx_range(struct __sk_buff, data):
info->reg_type = PTR_TO_PACKET;
break;
case bpf_ctx_range(struct __sk_buff, data_end):
info->reg_type = PTR_TO_PACKET_END;
break;
}
return bpf_skb_is_valid_access(off, size, type, prog, info);
}
static bool sk_msg_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
if (type == BPF_WRITE)
return false;
switch (off) {
case offsetof(struct sk_msg_md, data):
info->reg_type = PTR_TO_PACKET;
if (size != sizeof(__u64))
return false;
break;
case offsetof(struct sk_msg_md, data_end):
info->reg_type = PTR_TO_PACKET_END;
if (size != sizeof(__u64))
return false;
break;
default:
if (size != sizeof(__u32))
return false;
}
if (off < 0 || off >= sizeof(struct sk_msg_md))
return false;
if (off % size != 0)
return false;
return true;
}
static u32 bpf_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
int off;
switch (si->off) {
case offsetof(struct __sk_buff, len):
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, len, 4,
target_size));
break;
case offsetof(struct __sk_buff, protocol):
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, protocol, 2,
target_size));
break;
case offsetof(struct __sk_buff, vlan_proto):
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, vlan_proto, 2,
target_size));
break;
case offsetof(struct __sk_buff, priority):
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, priority, 4,
target_size));
else
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, priority, 4,
target_size));
break;
case offsetof(struct __sk_buff, ingress_ifindex):
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, skb_iif, 4,
target_size));
break;
case offsetof(struct __sk_buff, ifindex):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, dev));
*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
bpf_target_off(struct net_device, ifindex, 4,
target_size));
break;
case offsetof(struct __sk_buff, hash):
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, hash, 4,
target_size));
break;
case offsetof(struct __sk_buff, mark):
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, mark, 4,
target_size));
else
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, mark, 4,
target_size));
break;
case offsetof(struct __sk_buff, pkt_type):
*target_size = 1;
*insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
PKT_TYPE_OFFSET());
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
#ifdef __BIG_ENDIAN_BITFIELD
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
#endif
break;
case offsetof(struct __sk_buff, queue_mapping):
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, queue_mapping, 2,
target_size));
break;
case offsetof(struct __sk_buff, vlan_present):
case offsetof(struct __sk_buff, vlan_tci):
BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, vlan_tci, 2,
target_size));
if (si->off == offsetof(struct __sk_buff, vlan_tci)) {
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg,
~VLAN_TAG_PRESENT);
} else {
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 12);
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
}
break;
case offsetof(struct __sk_buff, cb[0]) ...
offsetofend(struct __sk_buff, cb[4]) - 1:
BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, data) < 20);
BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
offsetof(struct qdisc_skb_cb, data)) %
sizeof(__u64));
prog->cb_access = 1;
off = si->off;
off -= offsetof(struct __sk_buff, cb[0]);
off += offsetof(struct sk_buff, cb);
off += offsetof(struct qdisc_skb_cb, data);
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
si->src_reg, off);
else
*insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
si->src_reg, off);
break;
case offsetof(struct __sk_buff, tc_classid):
BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, tc_classid) != 2);
off = si->off;
off -= offsetof(struct __sk_buff, tc_classid);
off += offsetof(struct sk_buff, cb);
off += offsetof(struct qdisc_skb_cb, tc_classid);
*target_size = 2;
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_H, si->dst_reg,
si->src_reg, off);
else
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
si->src_reg, off);
break;
case offsetof(struct __sk_buff, data):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, data));
break;
case offsetof(struct __sk_buff, data_meta):
off = si->off;
off -= offsetof(struct __sk_buff, data_meta);
off += offsetof(struct sk_buff, cb);
off += offsetof(struct bpf_skb_data_end, data_meta);
*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
si->src_reg, off);
break;
case offsetof(struct __sk_buff, data_end):
off = si->off;
off -= offsetof(struct __sk_buff, data_end);
off += offsetof(struct sk_buff, cb);
off += offsetof(struct bpf_skb_data_end, data_end);
*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
si->src_reg, off);
break;
case offsetof(struct __sk_buff, tc_index):
#ifdef CONFIG_NET_SCHED
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, tc_index, 2,
target_size));
else
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, tc_index, 2,
target_size));
#else
*target_size = 2;
if (type == BPF_WRITE)
*insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
else
*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
#endif
break;
case offsetof(struct __sk_buff, napi_id):
#if defined(CONFIG_NET_RX_BUSY_POLL)
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
bpf_target_off(struct sk_buff, napi_id, 4,
target_size));
*insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
#else
*target_size = 4;
*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
#endif
break;
case offsetof(struct __sk_buff, family):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
bpf_target_off(struct sock_common,
skc_family,
2, target_size));
break;
case offsetof(struct __sk_buff, remote_ip4):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
bpf_target_off(struct sock_common,
skc_daddr,
4, target_size));
break;
case offsetof(struct __sk_buff, local_ip4):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
skc_rcv_saddr) != 4);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
bpf_target_off(struct sock_common,
skc_rcv_saddr,
4, target_size));
break;
case offsetof(struct __sk_buff, remote_ip6[0]) ...
offsetof(struct __sk_buff, remote_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
skc_v6_daddr.s6_addr32[0]) != 4);
off = si->off;
off -= offsetof(struct __sk_buff, remote_ip6[0]);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct sock_common,
skc_v6_daddr.s6_addr32[0]) +
off);
#else
*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
break;
case offsetof(struct __sk_buff, local_ip6[0]) ...
offsetof(struct __sk_buff, local_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
skc_v6_rcv_saddr.s6_addr32[0]) != 4);
off = si->off;
off -= offsetof(struct __sk_buff, local_ip6[0]);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct sock_common,
skc_v6_rcv_saddr.s6_addr32[0]) +
off);
#else
*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
break;
case offsetof(struct __sk_buff, remote_port):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
bpf_target_off(struct sock_common,
skc_dport,
2, target_size));
#ifndef __BIG_ENDIAN_BITFIELD
*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
#endif
break;
case offsetof(struct __sk_buff, local_port):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
bpf_target_off(struct sock_common,
skc_num, 2, target_size));
break;
}
return insn - insn_buf;
}
static u32 sock_filter_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
int off;
switch (si->off) {
case offsetof(struct bpf_sock, bound_dev_if):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_bound_dev_if) != 4);
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
offsetof(struct sock, sk_bound_dev_if));
else
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
offsetof(struct sock, sk_bound_dev_if));
break;
case offsetof(struct bpf_sock, mark):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_mark) != 4);
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
offsetof(struct sock, sk_mark));
else
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
offsetof(struct sock, sk_mark));
break;
case offsetof(struct bpf_sock, priority):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_priority) != 4);
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
offsetof(struct sock, sk_priority));
else
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
offsetof(struct sock, sk_priority));
break;
case offsetof(struct bpf_sock, family):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_family) != 2);
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
offsetof(struct sock, sk_family));
break;
case offsetof(struct bpf_sock, type):
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
offsetof(struct sock, __sk_flags_offset));
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK);
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT);
break;
case offsetof(struct bpf_sock, protocol):
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
offsetof(struct sock, __sk_flags_offset));
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_PROTO_SHIFT);
break;
case offsetof(struct bpf_sock, src_ip4):
*insn++ = BPF_LDX_MEM(
BPF_SIZE(si->code), si->dst_reg, si->src_reg,
bpf_target_off(struct sock_common, skc_rcv_saddr,
FIELD_SIZEOF(struct sock_common,
skc_rcv_saddr),
target_size));
break;
case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
off = si->off;
off -= offsetof(struct bpf_sock, src_ip6[0]);
*insn++ = BPF_LDX_MEM(
BPF_SIZE(si->code), si->dst_reg, si->src_reg,
bpf_target_off(
struct sock_common,
skc_v6_rcv_saddr.s6_addr32[0],
FIELD_SIZEOF(struct sock_common,
skc_v6_rcv_saddr.s6_addr32[0]),
target_size) + off);
#else
(void)off;
*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
break;
case offsetof(struct bpf_sock, src_port):
*insn++ = BPF_LDX_MEM(
BPF_FIELD_SIZEOF(struct sock_common, skc_num),
si->dst_reg, si->src_reg,
bpf_target_off(struct sock_common, skc_num,
FIELD_SIZEOF(struct sock_common,
skc_num),
target_size));
break;
}
return insn - insn_buf;
}
static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
switch (si->off) {
case offsetof(struct __sk_buff, ifindex):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
si->dst_reg, si->src_reg,
offsetof(struct sk_buff, dev));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
bpf_target_off(struct net_device, ifindex, 4,
target_size));
break;
default:
return bpf_convert_ctx_access(type, si, insn_buf, prog,
target_size);
}
return insn - insn_buf;
}
static u32 xdp_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
switch (si->off) {
case offsetof(struct xdp_md, data):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
si->dst_reg, si->src_reg,
offsetof(struct xdp_buff, data));
break;
case offsetof(struct xdp_md, data_meta):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta),
si->dst_reg, si->src_reg,
offsetof(struct xdp_buff, data_meta));
break;
case offsetof(struct xdp_md, data_end):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
si->dst_reg, si->src_reg,
offsetof(struct xdp_buff, data_end));
break;
case offsetof(struct xdp_md, ingress_ifindex):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
si->dst_reg, si->src_reg,
offsetof(struct xdp_buff, rxq));
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev),
si->dst_reg, si->dst_reg,
offsetof(struct xdp_rxq_info, dev));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct net_device, ifindex));
break;
case offsetof(struct xdp_md, rx_queue_index):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
si->dst_reg, si->src_reg,
offsetof(struct xdp_buff, rxq));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct xdp_rxq_info,
queue_index));
break;
}
return insn - insn_buf;
}
/* SOCK_ADDR_LOAD_NESTED_FIELD() loads Nested Field S.F.NF where S is type of
* context Structure, F is Field in context structure that contains a pointer
* to Nested Structure of type NS that has the field NF.
*
* SIZE encodes the load size (BPF_B, BPF_H, etc). It's up to caller to make
* sure that SIZE is not greater than actual size of S.F.NF.
*
* If offset OFF is provided, the load happens from that offset relative to
* offset of NF.
*/
#define SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF) \
do { \
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), si->dst_reg, \
si->src_reg, offsetof(S, F)); \
*insn++ = BPF_LDX_MEM( \
SIZE, si->dst_reg, si->dst_reg, \
bpf_target_off(NS, NF, FIELD_SIZEOF(NS, NF), \
target_size) \
+ OFF); \
} while (0)
#define SOCK_ADDR_LOAD_NESTED_FIELD(S, NS, F, NF) \
SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, \
BPF_FIELD_SIZEOF(NS, NF), 0)
/* SOCK_ADDR_STORE_NESTED_FIELD_OFF() has semantic similar to
* SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF() but for store operation.
*
* It doesn't support SIZE argument though since narrow stores are not
* supported for now.
*
* In addition it uses Temporary Field TF (member of struct S) as the 3rd
* "register" since two registers available in convert_ctx_access are not
* enough: we can't override neither SRC, since it contains value to store, nor
* DST since it contains pointer to context that may be used by later
* instructions. But we need a temporary place to save pointer to nested
* structure whose field we want to store to.
*/
#define SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, OFF, TF) \
do { \
int tmp_reg = BPF_REG_9; \
if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \
--tmp_reg; \
if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \
--tmp_reg; \
*insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, tmp_reg, \
offsetof(S, TF)); \
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), tmp_reg, \
si->dst_reg, offsetof(S, F)); \
*insn++ = BPF_STX_MEM( \
BPF_FIELD_SIZEOF(NS, NF), tmp_reg, si->src_reg, \
bpf_target_off(NS, NF, FIELD_SIZEOF(NS, NF), \
target_size) \
+ OFF); \
*insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, si->dst_reg, \
offsetof(S, TF)); \
} while (0)
#define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF, \
TF) \
do { \
if (type == BPF_WRITE) { \
SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, OFF, \
TF); \
} else { \
SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( \
S, NS, F, NF, SIZE, OFF); \
} \
} while (0)
#define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(S, NS, F, NF, TF) \
SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( \
S, NS, F, NF, BPF_FIELD_SIZEOF(NS, NF), 0, TF)
static u32 sock_addr_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
int off;
switch (si->off) {
case offsetof(struct bpf_sock_addr, user_family):
SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
struct sockaddr, uaddr, sa_family);
break;
case offsetof(struct bpf_sock_addr, user_ip4):
SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
struct bpf_sock_addr_kern, struct sockaddr_in, uaddr,
sin_addr, BPF_SIZE(si->code), 0, tmp_reg);
break;
case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
off = si->off;
off -= offsetof(struct bpf_sock_addr, user_ip6[0]);
SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
sin6_addr.s6_addr32[0], BPF_SIZE(si->code), off,
tmp_reg);
break;
case offsetof(struct bpf_sock_addr, user_port):
/* To get port we need to know sa_family first and then treat
* sockaddr as either sockaddr_in or sockaddr_in6.
* Though we can simplify since port field has same offset and
* size in both structures.
* Here we check this invariant and use just one of the
* structures if it's true.
*/
BUILD_BUG_ON(offsetof(struct sockaddr_in, sin_port) !=
offsetof(struct sockaddr_in6, sin6_port));
BUILD_BUG_ON(FIELD_SIZEOF(struct sockaddr_in, sin_port) !=
FIELD_SIZEOF(struct sockaddr_in6, sin6_port));
SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(struct bpf_sock_addr_kern,
struct sockaddr_in6, uaddr,
sin6_port, tmp_reg);
break;
case offsetof(struct bpf_sock_addr, family):
SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
struct sock, sk, sk_family);
break;
case offsetof(struct bpf_sock_addr, type):
SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(
struct bpf_sock_addr_kern, struct sock, sk,
__sk_flags_offset, BPF_W, 0);
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK);
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT);
break;
case offsetof(struct bpf_sock_addr, protocol):
SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(
struct bpf_sock_addr_kern, struct sock, sk,
__sk_flags_offset, BPF_W, 0);
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg,
SK_FL_PROTO_SHIFT);
break;
case offsetof(struct bpf_sock_addr, msg_src_ip4):
/* Treat t_ctx as struct in_addr for msg_src_ip4. */
SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
struct bpf_sock_addr_kern, struct in_addr, t_ctx,
s_addr, BPF_SIZE(si->code), 0, tmp_reg);
break;
case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
msg_src_ip6[3]):
off = si->off;
off -= offsetof(struct bpf_sock_addr, msg_src_ip6[0]);
/* Treat t_ctx as struct in6_addr for msg_src_ip6. */
SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
struct bpf_sock_addr_kern, struct in6_addr, t_ctx,
s6_addr32[0], BPF_SIZE(si->code), off, tmp_reg);
break;
}
return insn - insn_buf;
}
static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog,
u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
int off;
switch (si->off) {
case offsetof(struct bpf_sock_ops, op) ...
offsetof(struct bpf_sock_ops, replylong[3]):
BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, op) !=
FIELD_SIZEOF(struct bpf_sock_ops_kern, op));
BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, reply) !=
FIELD_SIZEOF(struct bpf_sock_ops_kern, reply));
BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, replylong) !=
FIELD_SIZEOF(struct bpf_sock_ops_kern, replylong));
off = si->off;
off -= offsetof(struct bpf_sock_ops, op);
off += offsetof(struct bpf_sock_ops_kern, op);
if (type == BPF_WRITE)
*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
off);
else
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
off);
break;
case offsetof(struct bpf_sock_ops, family):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_family));
break;
case offsetof(struct bpf_sock_ops, remote_ip4):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_daddr));
break;
case offsetof(struct bpf_sock_ops, local_ip4):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
skc_rcv_saddr) != 4);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct sock_common,
skc_rcv_saddr));
break;
case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
offsetof(struct bpf_sock_ops, remote_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
skc_v6_daddr.s6_addr32[0]) != 4);
off = si->off;
off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct sock_common,
skc_v6_daddr.s6_addr32[0]) +
off);
#else
*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
break;
case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
offsetof(struct bpf_sock_ops, local_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
skc_v6_rcv_saddr.s6_addr32[0]) != 4);
off = si->off;
off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct sock_common,
skc_v6_rcv_saddr.s6_addr32[0]) +
off);
#else
*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
break;
case offsetof(struct bpf_sock_ops, remote_port):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_dport));
#ifndef __BIG_ENDIAN_BITFIELD
*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
#endif
break;
case offsetof(struct bpf_sock_ops, local_port):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_num));
break;
case offsetof(struct bpf_sock_ops, is_fullsock):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern,
is_fullsock),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern,
is_fullsock));
break;
case offsetof(struct bpf_sock_ops, state):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_state) != 1);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_state));
break;
case offsetof(struct bpf_sock_ops, rtt_min):
BUILD_BUG_ON(FIELD_SIZEOF(struct tcp_sock, rtt_min) !=
sizeof(struct minmax));
BUILD_BUG_ON(sizeof(struct minmax) <
sizeof(struct minmax_sample));
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct bpf_sock_ops_kern, sk),
si->dst_reg, si->src_reg,
offsetof(struct bpf_sock_ops_kern, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct tcp_sock, rtt_min) +
FIELD_SIZEOF(struct minmax_sample, t));
break;
/* Helper macro for adding read access to tcp_sock or sock fields. */
#define SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \
do { \
BUILD_BUG_ON(FIELD_SIZEOF(OBJ, OBJ_FIELD) > \
FIELD_SIZEOF(struct bpf_sock_ops, BPF_FIELD)); \
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
struct bpf_sock_ops_kern, \
is_fullsock), \
si->dst_reg, si->src_reg, \
offsetof(struct bpf_sock_ops_kern, \
is_fullsock)); \
*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 2); \
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
struct bpf_sock_ops_kern, sk),\
si->dst_reg, si->src_reg, \
offsetof(struct bpf_sock_ops_kern, sk));\
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(OBJ, \
OBJ_FIELD), \
si->dst_reg, si->dst_reg, \
offsetof(OBJ, OBJ_FIELD)); \
} while (0)
/* Helper macro for adding write access to tcp_sock or sock fields.
* The macro is called with two registers, dst_reg which contains a pointer
* to ctx (context) and src_reg which contains the value that should be
* stored. However, we need an additional register since we cannot overwrite
* dst_reg because it may be used later in the program.
* Instead we "borrow" one of the other register. We first save its value
* into a new (temp) field in bpf_sock_ops_kern, use it, and then restore
* it at the end of the macro.
*/
#define SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \
do { \
int reg = BPF_REG_9; \
BUILD_BUG_ON(FIELD_SIZEOF(OBJ, OBJ_FIELD) > \
FIELD_SIZEOF(struct bpf_sock_ops, BPF_FIELD)); \
if (si->dst_reg == reg || si->src_reg == reg) \
reg--; \
if (si->dst_reg == reg || si->src_reg == reg) \
reg--; \
*insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, reg, \
offsetof(struct bpf_sock_ops_kern, \
temp)); \
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
struct bpf_sock_ops_kern, \
is_fullsock), \
reg, si->dst_reg, \
offsetof(struct bpf_sock_ops_kern, \
is_fullsock)); \
*insn++ = BPF_JMP_IMM(BPF_JEQ, reg, 0, 2); \
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
struct bpf_sock_ops_kern, sk),\
reg, si->dst_reg, \
offsetof(struct bpf_sock_ops_kern, sk));\
*insn++ = BPF_STX_MEM(BPF_FIELD_SIZEOF(OBJ, OBJ_FIELD), \
reg, si->src_reg, \
offsetof(OBJ, OBJ_FIELD)); \
*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->dst_reg, \
offsetof(struct bpf_sock_ops_kern, \
temp)); \
} while (0)
#define SOCK_OPS_GET_OR_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ, TYPE) \
do { \
if (TYPE == BPF_WRITE) \
SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \
else \
SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \
} while (0)
case offsetof(struct bpf_sock_ops, snd_cwnd):
SOCK_OPS_GET_FIELD(snd_cwnd, snd_cwnd, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, srtt_us):
SOCK_OPS_GET_FIELD(srtt_us, srtt_us, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, bpf_sock_ops_cb_flags):
SOCK_OPS_GET_FIELD(bpf_sock_ops_cb_flags, bpf_sock_ops_cb_flags,
struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, snd_ssthresh):
SOCK_OPS_GET_FIELD(snd_ssthresh, snd_ssthresh, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, rcv_nxt):
SOCK_OPS_GET_FIELD(rcv_nxt, rcv_nxt, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, snd_nxt):
SOCK_OPS_GET_FIELD(snd_nxt, snd_nxt, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, snd_una):
SOCK_OPS_GET_FIELD(snd_una, snd_una, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, mss_cache):
SOCK_OPS_GET_FIELD(mss_cache, mss_cache, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, ecn_flags):
SOCK_OPS_GET_FIELD(ecn_flags, ecn_flags, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, rate_delivered):
SOCK_OPS_GET_FIELD(rate_delivered, rate_delivered,
struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, rate_interval_us):
SOCK_OPS_GET_FIELD(rate_interval_us, rate_interval_us,
struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, packets_out):
SOCK_OPS_GET_FIELD(packets_out, packets_out, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, retrans_out):
SOCK_OPS_GET_FIELD(retrans_out, retrans_out, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, total_retrans):
SOCK_OPS_GET_FIELD(total_retrans, total_retrans,
struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, segs_in):
SOCK_OPS_GET_FIELD(segs_in, segs_in, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, data_segs_in):
SOCK_OPS_GET_FIELD(data_segs_in, data_segs_in, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, segs_out):
SOCK_OPS_GET_FIELD(segs_out, segs_out, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, data_segs_out):
SOCK_OPS_GET_FIELD(data_segs_out, data_segs_out,
struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, lost_out):
SOCK_OPS_GET_FIELD(lost_out, lost_out, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, sacked_out):
SOCK_OPS_GET_FIELD(sacked_out, sacked_out, struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, sk_txhash):
SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash,
struct sock, type);
break;
case offsetof(struct bpf_sock_ops, bytes_received):
SOCK_OPS_GET_FIELD(bytes_received, bytes_received,
struct tcp_sock);
break;
case offsetof(struct bpf_sock_ops, bytes_acked):
SOCK_OPS_GET_FIELD(bytes_acked, bytes_acked, struct tcp_sock);
break;
}
return insn - insn_buf;
}
static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
int off;
switch (si->off) {
case offsetof(struct __sk_buff, data_end):
off = si->off;
off -= offsetof(struct __sk_buff, data_end);
off += offsetof(struct sk_buff, cb);
off += offsetof(struct tcp_skb_cb, bpf.data_end);
*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
si->src_reg, off);
break;
default:
return bpf_convert_ctx_access(type, si, insn_buf, prog,
target_size);
}
return insn - insn_buf;
}
static u32 sk_msg_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
#if IS_ENABLED(CONFIG_IPV6)
int off;
#endif
switch (si->off) {
case offsetof(struct sk_msg_md, data):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_buff, data),
si->dst_reg, si->src_reg,
offsetof(struct sk_msg_buff, data));
break;
case offsetof(struct sk_msg_md, data_end):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_buff, data_end),
si->dst_reg, si->src_reg,
offsetof(struct sk_msg_buff, data_end));
break;
case offsetof(struct sk_msg_md, family):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct sk_msg_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_msg_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_family));
break;
case offsetof(struct sk_msg_md, remote_ip4):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct sk_msg_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_msg_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_daddr));
break;
case offsetof(struct sk_msg_md, local_ip4):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
skc_rcv_saddr) != 4);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct sk_msg_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_msg_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct sock_common,
skc_rcv_saddr));
break;
case offsetof(struct sk_msg_md, remote_ip6[0]) ...
offsetof(struct sk_msg_md, remote_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
skc_v6_daddr.s6_addr32[0]) != 4);
off = si->off;
off -= offsetof(struct sk_msg_md, remote_ip6[0]);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct sk_msg_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_msg_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct sock_common,
skc_v6_daddr.s6_addr32[0]) +
off);
#else
*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
break;
case offsetof(struct sk_msg_md, local_ip6[0]) ...
offsetof(struct sk_msg_md, local_ip6[3]):
#if IS_ENABLED(CONFIG_IPV6)
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
skc_v6_rcv_saddr.s6_addr32[0]) != 4);
off = si->off;
off -= offsetof(struct sk_msg_md, local_ip6[0]);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct sk_msg_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_msg_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
offsetof(struct sock_common,
skc_v6_rcv_saddr.s6_addr32[0]) +
off);
#else
*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
#endif
break;
case offsetof(struct sk_msg_md, remote_port):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct sk_msg_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_msg_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_dport));
#ifndef __BIG_ENDIAN_BITFIELD
*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
#endif
break;
case offsetof(struct sk_msg_md, local_port):
BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
struct sk_msg_buff, sk),
si->dst_reg, si->src_reg,
offsetof(struct sk_msg_buff, sk));
*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
offsetof(struct sock_common, skc_num));
break;
}
return insn - insn_buf;
}
const struct bpf_verifier_ops sk_filter_verifier_ops = {
.get_func_proto = sk_filter_func_proto,
.is_valid_access = sk_filter_is_valid_access,
.convert_ctx_access = bpf_convert_ctx_access,
.gen_ld_abs = bpf_gen_ld_abs,
};
const struct bpf_prog_ops sk_filter_prog_ops = {
.test_run = bpf_prog_test_run_skb,
};
const struct bpf_verifier_ops tc_cls_act_verifier_ops = {
.get_func_proto = tc_cls_act_func_proto,
.is_valid_access = tc_cls_act_is_valid_access,
.convert_ctx_access = tc_cls_act_convert_ctx_access,
.gen_prologue = tc_cls_act_prologue,
.gen_ld_abs = bpf_gen_ld_abs,
};
const struct bpf_prog_ops tc_cls_act_prog_ops = {
.test_run = bpf_prog_test_run_skb,
};
const struct bpf_verifier_ops xdp_verifier_ops = {
.get_func_proto = xdp_func_proto,
.is_valid_access = xdp_is_valid_access,
.convert_ctx_access = xdp_convert_ctx_access,
};
const struct bpf_prog_ops xdp_prog_ops = {
.test_run = bpf_prog_test_run_xdp,
};
const struct bpf_verifier_ops cg_skb_verifier_ops = {
.get_func_proto = cg_skb_func_proto,
.is_valid_access = sk_filter_is_valid_access,
.convert_ctx_access = bpf_convert_ctx_access,
};
const struct bpf_prog_ops cg_skb_prog_ops = {
.test_run = bpf_prog_test_run_skb,
};
const struct bpf_verifier_ops lwt_in_verifier_ops = {
.get_func_proto = lwt_in_func_proto,
.is_valid_access = lwt_is_valid_access,
.convert_ctx_access = bpf_convert_ctx_access,
};
const struct bpf_prog_ops lwt_in_prog_ops = {
.test_run = bpf_prog_test_run_skb,
};
const struct bpf_verifier_ops lwt_out_verifier_ops = {
.get_func_proto = lwt_out_func_proto,
.is_valid_access = lwt_is_valid_access,
.convert_ctx_access = bpf_convert_ctx_access,
};
const struct bpf_prog_ops lwt_out_prog_ops = {
.test_run = bpf_prog_test_run_skb,
};
const struct bpf_verifier_ops lwt_xmit_verifier_ops = {
.get_func_proto = lwt_xmit_func_proto,
.is_valid_access = lwt_is_valid_access,
.convert_ctx_access = bpf_convert_ctx_access,
.gen_prologue = tc_cls_act_prologue,
};
const struct bpf_prog_ops lwt_xmit_prog_ops = {
.test_run = bpf_prog_test_run_skb,
};
const struct bpf_verifier_ops lwt_seg6local_verifier_ops = {
.get_func_proto = lwt_seg6local_func_proto,
.is_valid_access = lwt_is_valid_access,
.convert_ctx_access = bpf_convert_ctx_access,
};
const struct bpf_prog_ops lwt_seg6local_prog_ops = {
.test_run = bpf_prog_test_run_skb,
};
const struct bpf_verifier_ops cg_sock_verifier_ops = {
.get_func_proto = sock_filter_func_proto,
.is_valid_access = sock_filter_is_valid_access,
.convert_ctx_access = sock_filter_convert_ctx_access,
};
const struct bpf_prog_ops cg_sock_prog_ops = {
};
const struct bpf_verifier_ops cg_sock_addr_verifier_ops = {
.get_func_proto = sock_addr_func_proto,
.is_valid_access = sock_addr_is_valid_access,
.convert_ctx_access = sock_addr_convert_ctx_access,
};
const struct bpf_prog_ops cg_sock_addr_prog_ops = {
};
const struct bpf_verifier_ops sock_ops_verifier_ops = {
.get_func_proto = sock_ops_func_proto,
.is_valid_access = sock_ops_is_valid_access,
.convert_ctx_access = sock_ops_convert_ctx_access,
};
const struct bpf_prog_ops sock_ops_prog_ops = {
};
const struct bpf_verifier_ops sk_skb_verifier_ops = {
.get_func_proto = sk_skb_func_proto,
.is_valid_access = sk_skb_is_valid_access,
.convert_ctx_access = sk_skb_convert_ctx_access,
.gen_prologue = sk_skb_prologue,
};
const struct bpf_prog_ops sk_skb_prog_ops = {
};
const struct bpf_verifier_ops sk_msg_verifier_ops = {
.get_func_proto = sk_msg_func_proto,
.is_valid_access = sk_msg_is_valid_access,
.convert_ctx_access = sk_msg_convert_ctx_access,
};
const struct bpf_prog_ops sk_msg_prog_ops = {
};
int sk_detach_filter(struct sock *sk)
{
int ret = -ENOENT;
struct sk_filter *filter;
if (sock_flag(sk, SOCK_FILTER_LOCKED))
return -EPERM;
filter = rcu_dereference_protected(sk->sk_filter,
lockdep_sock_is_held(sk));
if (filter) {
RCU_INIT_POINTER(sk->sk_filter, NULL);
sk_filter_uncharge(sk, filter);
ret = 0;
}
return ret;
}
EXPORT_SYMBOL_GPL(sk_detach_filter);
int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf,
unsigned int len)
{
struct sock_fprog_kern *fprog;
struct sk_filter *filter;
int ret = 0;
lock_sock(sk);
filter = rcu_dereference_protected(sk->sk_filter,
lockdep_sock_is_held(sk));
if (!filter)
goto out;
/* We're copying the filter that has been originally attached,
* so no conversion/decode needed anymore. eBPF programs that
* have no original program cannot be dumped through this.
*/
ret = -EACCES;
fprog = filter->prog->orig_prog;
if (!fprog)
goto out;
ret = fprog->len;
if (!len)
/* User space only enquires number of filter blocks. */
goto out;
ret = -EINVAL;
if (len < fprog->len)
goto out;
ret = -EFAULT;
if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog)))
goto out;
/* Instead of bytes, the API requests to return the number
* of filter blocks.
*/
ret = fprog->len;
out:
release_sock(sk);
return ret;
}
#ifdef CONFIG_INET
struct sk_reuseport_kern {
struct sk_buff *skb;
struct sock *sk;
struct sock *selected_sk;
void *data_end;
u32 hash;
u32 reuseport_id;
bool bind_inany;
};
static void bpf_init_reuseport_kern(struct sk_reuseport_kern *reuse_kern,
struct sock_reuseport *reuse,
struct sock *sk, struct sk_buff *skb,
u32 hash)
{
reuse_kern->skb = skb;
reuse_kern->sk = sk;
reuse_kern->selected_sk = NULL;
reuse_kern->data_end = skb->data + skb_headlen(skb);
reuse_kern->hash = hash;
reuse_kern->reuseport_id = reuse->reuseport_id;
reuse_kern->bind_inany = reuse->bind_inany;
}
struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
struct bpf_prog *prog, struct sk_buff *skb,
u32 hash)
{
struct sk_reuseport_kern reuse_kern;
enum sk_action action;
bpf_init_reuseport_kern(&reuse_kern, reuse, sk, skb, hash);
action = BPF_PROG_RUN(prog, &reuse_kern);
if (action == SK_PASS)
return reuse_kern.selected_sk;
else
return ERR_PTR(-ECONNREFUSED);
}
BPF_CALL_4(sk_select_reuseport, struct sk_reuseport_kern *, reuse_kern,
struct bpf_map *, map, void *, key, u32, flags)
{
struct sock_reuseport *reuse;
struct sock *selected_sk;
selected_sk = map->ops->map_lookup_elem(map, key);
if (!selected_sk)
return -ENOENT;
reuse = rcu_dereference(selected_sk->sk_reuseport_cb);
if (!reuse)
/* selected_sk is unhashed (e.g. by close()) after the
* above map_lookup_elem(). Treat selected_sk has already
* been removed from the map.
*/
return -ENOENT;
if (unlikely(reuse->reuseport_id != reuse_kern->reuseport_id)) {
struct sock *sk;
if (unlikely(!reuse_kern->reuseport_id))
/* There is a small race between adding the
* sk to the map and setting the
* reuse_kern->reuseport_id.
* Treat it as the sk has not been added to
* the bpf map yet.
*/
return -ENOENT;
sk = reuse_kern->sk;
if (sk->sk_protocol != selected_sk->sk_protocol)
return -EPROTOTYPE;
else if (sk->sk_family != selected_sk->sk_family)
return -EAFNOSUPPORT;
/* Catch all. Likely bound to a different sockaddr. */
return -EBADFD;
}
reuse_kern->selected_sk = selected_sk;
return 0;
}
static const struct bpf_func_proto sk_select_reuseport_proto = {
.func = sk_select_reuseport,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_CONST_MAP_PTR,
.arg3_type = ARG_PTR_TO_MAP_KEY,
.arg4_type = ARG_ANYTHING,
};
BPF_CALL_4(sk_reuseport_load_bytes,
const struct sk_reuseport_kern *, reuse_kern, u32, offset,
void *, to, u32, len)
{
return ____bpf_skb_load_bytes(reuse_kern->skb, offset, to, len);
}
static const struct bpf_func_proto sk_reuseport_load_bytes_proto = {
.func = sk_reuseport_load_bytes,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_PTR_TO_UNINIT_MEM,
.arg4_type = ARG_CONST_SIZE,
};
BPF_CALL_5(sk_reuseport_load_bytes_relative,
const struct sk_reuseport_kern *, reuse_kern, u32, offset,
void *, to, u32, len, u32, start_header)
{
return ____bpf_skb_load_bytes_relative(reuse_kern->skb, offset, to,
len, start_header);
}
static const struct bpf_func_proto sk_reuseport_load_bytes_relative_proto = {
.func = sk_reuseport_load_bytes_relative,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_CTX,
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_PTR_TO_UNINIT_MEM,
.arg4_type = ARG_CONST_SIZE,
.arg5_type = ARG_ANYTHING,
};
static const struct bpf_func_proto *
sk_reuseport_func_proto(enum bpf_func_id func_id,
const struct bpf_prog *prog)
{
switch (func_id) {
case BPF_FUNC_sk_select_reuseport:
return &sk_select_reuseport_proto;
case BPF_FUNC_skb_load_bytes:
return &sk_reuseport_load_bytes_proto;
case BPF_FUNC_skb_load_bytes_relative:
return &sk_reuseport_load_bytes_relative_proto;
default:
return bpf_base_func_proto(func_id);
}
}
static bool
sk_reuseport_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
struct bpf_insn_access_aux *info)
{
const u32 size_default = sizeof(__u32);
if (off < 0 || off >= sizeof(struct sk_reuseport_md) ||
off % size || type != BPF_READ)
return false;
switch (off) {
case offsetof(struct sk_reuseport_md, data):
info->reg_type = PTR_TO_PACKET;
return size == sizeof(__u64);
case offsetof(struct sk_reuseport_md, data_end):
info->reg_type = PTR_TO_PACKET_END;
return size == sizeof(__u64);
case offsetof(struct sk_reuseport_md, hash):
return size == size_default;
/* Fields that allow narrowing */
case offsetof(struct sk_reuseport_md, eth_protocol):
if (size < FIELD_SIZEOF(struct sk_buff, protocol))
return false;
case offsetof(struct sk_reuseport_md, ip_protocol):
case offsetof(struct sk_reuseport_md, bind_inany):
case offsetof(struct sk_reuseport_md, len):
bpf_ctx_record_field_size(info, size_default);
return bpf_ctx_narrow_access_ok(off, size, size_default);
default:
return false;
}
}
#define SK_REUSEPORT_LOAD_FIELD(F) ({ \
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_reuseport_kern, F), \
si->dst_reg, si->src_reg, \
bpf_target_off(struct sk_reuseport_kern, F, \
FIELD_SIZEOF(struct sk_reuseport_kern, F), \
target_size)); \
})
#define SK_REUSEPORT_LOAD_SKB_FIELD(SKB_FIELD) \
SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern, \
struct sk_buff, \
skb, \
SKB_FIELD)
#define SK_REUSEPORT_LOAD_SK_FIELD_SIZE_OFF(SK_FIELD, BPF_SIZE, EXTRA_OFF) \
SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(struct sk_reuseport_kern, \
struct sock, \
sk, \
SK_FIELD, BPF_SIZE, EXTRA_OFF)
static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
struct bpf_prog *prog,
u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
switch (si->off) {
case offsetof(struct sk_reuseport_md, data):
SK_REUSEPORT_LOAD_SKB_FIELD(data);
break;
case offsetof(struct sk_reuseport_md, len):
SK_REUSEPORT_LOAD_SKB_FIELD(len);
break;
case offsetof(struct sk_reuseport_md, eth_protocol):
SK_REUSEPORT_LOAD_SKB_FIELD(protocol);
break;
case offsetof(struct sk_reuseport_md, ip_protocol):
BUILD_BUG_ON(hweight_long(SK_FL_PROTO_MASK) != BITS_PER_BYTE);
SK_REUSEPORT_LOAD_SK_FIELD_SIZE_OFF(__sk_flags_offset,
BPF_W, 0);
*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg,
SK_FL_PROTO_SHIFT);
/* SK_FL_PROTO_MASK and SK_FL_PROTO_SHIFT are endian
* aware. No further narrowing or masking is needed.
*/
*target_size = 1;
break;
case offsetof(struct sk_reuseport_md, data_end):
SK_REUSEPORT_LOAD_FIELD(data_end);
break;
case offsetof(struct sk_reuseport_md, hash):
SK_REUSEPORT_LOAD_FIELD(hash);
break;
case offsetof(struct sk_reuseport_md, bind_inany):
SK_REUSEPORT_LOAD_FIELD(bind_inany);
break;
}
return insn - insn_buf;
}
const struct bpf_verifier_ops sk_reuseport_verifier_ops = {
.get_func_proto = sk_reuseport_func_proto,
.is_valid_access = sk_reuseport_is_valid_access,
.convert_ctx_access = sk_reuseport_convert_ctx_access,
};
const struct bpf_prog_ops sk_reuseport_prog_ops = {
};
#endif /* CONFIG_INET */