diff --git a/include/linux/filter.h b/include/linux/filter.h index 425056c7f96ce..20384c4bed25e 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -1003,10 +1003,20 @@ struct bpf_sock_ops_kern { struct sock *sk; u32 op; union { + u32 args[4]; u32 reply; u32 replylong[4]; }; u32 is_fullsock; + u64 temp; /* temp and everything after is not + * initialized to 0 before calling + * the BPF program. New fields that + * should be initialized to 0 should + * be inserted before temp. + * temp is scratch storage used by + * sock_ops_convert_ctx_access + * as temporary storage of a register. + */ }; #endif /* __LINUX_FILTER_H__ */ diff --git a/include/linux/tcp.h b/include/linux/tcp.h index 4f93f0953c411..8f4c54986f974 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -335,6 +335,17 @@ struct tcp_sock { int linger2; + +/* Sock_ops bpf program related variables */ +#ifdef CONFIG_BPF + u8 bpf_sock_ops_cb_flags; /* Control calling BPF programs + * values defined in uapi/linux/tcp.h + */ +#define BPF_SOCK_OPS_TEST_FLAG(TP, ARG) (TP->bpf_sock_ops_cb_flags & ARG) +#else +#define BPF_SOCK_OPS_TEST_FLAG(TP, ARG) 0 +#endif + /* Receiver side RTT estimation */ struct { u32 rtt_us; diff --git a/include/net/tcp.h b/include/net/tcp.h index 5a1d26a185998..093e967a29600 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2006,12 +2006,12 @@ void tcp_cleanup_ulp(struct sock *sk); * program loaded). */ #ifdef CONFIG_BPF -static inline int tcp_call_bpf(struct sock *sk, int op) +static inline int tcp_call_bpf(struct sock *sk, int op, u32 nargs, u32 *args) { struct bpf_sock_ops_kern sock_ops; int ret; - memset(&sock_ops, 0, sizeof(sock_ops)); + memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp)); if (sk_fullsock(sk)) { sock_ops.is_fullsock = 1; sock_owned_by_me(sk); @@ -2019,6 +2019,8 @@ static inline int tcp_call_bpf(struct sock *sk, int op) sock_ops.sk = sk; sock_ops.op = op; + if (nargs > 0) + memcpy(sock_ops.args, args, nargs * sizeof(*args)); ret = BPF_CGROUP_RUN_PROG_SOCK_OPS(&sock_ops); if (ret == 0) @@ -2027,18 +2029,46 @@ static inline int tcp_call_bpf(struct sock *sk, int op) ret = -1; return ret; } + +static inline int tcp_call_bpf_2arg(struct sock *sk, int op, u32 arg1, u32 arg2) +{ + u32 args[2] = {arg1, arg2}; + + return tcp_call_bpf(sk, op, 2, args); +} + +static inline int tcp_call_bpf_3arg(struct sock *sk, int op, u32 arg1, u32 arg2, + u32 arg3) +{ + u32 args[3] = {arg1, arg2, arg3}; + + return tcp_call_bpf(sk, op, 3, args); +} + #else -static inline int tcp_call_bpf(struct sock *sk, int op) +static inline int tcp_call_bpf(struct sock *sk, int op, u32 nargs, u32 *args) { return -EPERM; } + +static inline int tcp_call_bpf_2arg(struct sock *sk, int op, u32 arg1, u32 arg2) +{ + return -EPERM; +} + +static inline int tcp_call_bpf_3arg(struct sock *sk, int op, u32 arg1, u32 arg2, + u32 arg3) +{ + return -EPERM; +} + #endif static inline u32 tcp_timeout_init(struct sock *sk) { int timeout; - timeout = tcp_call_bpf(sk, BPF_SOCK_OPS_TIMEOUT_INIT); + timeout = tcp_call_bpf(sk, BPF_SOCK_OPS_TIMEOUT_INIT, 0, NULL); if (timeout <= 0) timeout = TCP_TIMEOUT_INIT; @@ -2049,7 +2079,7 @@ static inline u32 tcp_rwnd_init_bpf(struct sock *sk) { int rwnd; - rwnd = tcp_call_bpf(sk, BPF_SOCK_OPS_RWND_INIT); + rwnd = tcp_call_bpf(sk, BPF_SOCK_OPS_RWND_INIT, 0, NULL); if (rwnd < 0) rwnd = 0; @@ -2058,7 +2088,7 @@ static inline u32 tcp_rwnd_init_bpf(struct sock *sk) static inline bool tcp_bpf_ca_needs_ecn(struct sock *sk) { - return (tcp_call_bpf(sk, BPF_SOCK_OPS_NEEDS_ECN) == 1); + return (tcp_call_bpf(sk, BPF_SOCK_OPS_NEEDS_ECN, 0, NULL) == 1); } #if IS_ENABLED(CONFIG_SMC) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 406c19d6016b2..db6bdc3751268 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -642,6 +642,14 @@ union bpf_attr { * @optlen: length of optval in bytes * Return: 0 or negative error * + * int bpf_sock_ops_cb_flags_set(bpf_sock_ops, flags) + * Set callback flags for sock_ops + * @bpf_sock_ops: pointer to bpf_sock_ops_kern struct + * @flags: flags value + * Return: 0 for no error + * -EINVAL if there is no full tcp socket + * bits in flags that are not supported by current kernel + * * int bpf_skb_adjust_room(skb, len_diff, mode, flags) * Grow or shrink room in sk_buff. * @skb: pointer to skb @@ -748,7 +756,8 @@ union bpf_attr { FN(perf_event_read_value), \ FN(perf_prog_read_value), \ FN(getsockopt), \ - FN(override_return), + FN(override_return), \ + FN(sock_ops_cb_flags_set), /* integer value in 'imm' field of BPF_CALL instruction selects which helper * function eBPF program intends to call @@ -952,8 +961,9 @@ struct bpf_map_info { struct bpf_sock_ops { __u32 op; union { - __u32 reply; - __u32 replylong[4]; + __u32 args[4]; /* Optionally passed to bpf program */ + __u32 reply; /* Returned by bpf program */ + __u32 replylong[4]; /* Optionally returned by bpf prog */ }; __u32 family; __u32 remote_ip4; /* Stored in network byte order */ @@ -968,8 +978,39 @@ struct bpf_sock_ops { */ __u32 snd_cwnd; __u32 srtt_us; /* Averaged RTT << 3 in usecs */ + __u32 bpf_sock_ops_cb_flags; /* flags defined in uapi/linux/tcp.h */ + __u32 state; + __u32 rtt_min; + __u32 snd_ssthresh; + __u32 rcv_nxt; + __u32 snd_nxt; + __u32 snd_una; + __u32 mss_cache; + __u32 ecn_flags; + __u32 rate_delivered; + __u32 rate_interval_us; + __u32 packets_out; + __u32 retrans_out; + __u32 total_retrans; + __u32 segs_in; + __u32 data_segs_in; + __u32 segs_out; + __u32 data_segs_out; + __u32 lost_out; + __u32 sacked_out; + __u32 sk_txhash; + __u64 bytes_received; + __u64 bytes_acked; }; +/* Definitions for bpf_sock_ops_cb_flags */ +#define BPF_SOCK_OPS_RTO_CB_FLAG (1<<0) +#define BPF_SOCK_OPS_RETRANS_CB_FLAG (1<<1) +#define BPF_SOCK_OPS_STATE_CB_FLAG (1<<2) +#define BPF_SOCK_OPS_ALL_CB_FLAGS 0x7 /* Mask of all currently + * supported cb flags + */ + /* List of known BPF sock_ops operators. * New entries can only be added at the end */ @@ -1003,6 +1044,43 @@ enum { * a congestion threshold. RTTs above * this indicate congestion */ + BPF_SOCK_OPS_RTO_CB, /* Called when an RTO has triggered. + * Arg1: value of icsk_retransmits + * Arg2: value of icsk_rto + * Arg3: whether RTO has expired + */ + BPF_SOCK_OPS_RETRANS_CB, /* Called when skb is retransmitted. + * Arg1: sequence number of 1st byte + * Arg2: # segments + * Arg3: return value of + * tcp_transmit_skb (0 => success) + */ + BPF_SOCK_OPS_STATE_CB, /* Called when TCP changes state. + * Arg1: old_state + * Arg2: new_state + */ +}; + +/* List of TCP states. There is a build check in net/ipv4/tcp.c to detect + * changes between the TCP and BPF versions. Ideally this should never happen. + * If it does, we need to add code to convert them before calling + * the BPF sock_ops function. + */ +enum { + BPF_TCP_ESTABLISHED = 1, + BPF_TCP_SYN_SENT, + BPF_TCP_SYN_RECV, + BPF_TCP_FIN_WAIT1, + BPF_TCP_FIN_WAIT2, + BPF_TCP_TIME_WAIT, + BPF_TCP_CLOSE, + BPF_TCP_CLOSE_WAIT, + BPF_TCP_LAST_ACK, + BPF_TCP_LISTEN, + BPF_TCP_CLOSING, /* Now a valid state */ + BPF_TCP_NEW_SYN_RECV, + + BPF_TCP_MAX_STATES /* Leave at the end! */ }; #define TCP_BPF_IW 1001 /* Set TCP initial congestion window */ diff --git a/net/core/filter.c b/net/core/filter.c index 18da42a81d0c8..fe2c7937351f5 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3232,6 +3232,29 @@ BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock, ret = -EINVAL; } #ifdef CONFIG_INET +#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) { @@ -3241,7 +3264,8 @@ BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock, 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); + ret = tcp_set_congestion_control(sk, name, false, + reinit); } else { struct tcp_sock *tp = tcp_sk(sk); @@ -3307,6 +3331,22 @@ BPF_CALL_5(bpf_getsockopt, struct bpf_sock_ops_kern *, bpf_sock, } else { 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; } @@ -3328,6 +3368,33 @@ static const struct bpf_func_proto bpf_getsockopt_proto = { .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 (!sk_fullsock(sk)) + return -EINVAL; + +#ifdef CONFIG_INET + if (val) + tcp_sk(sk)->bpf_sock_ops_cb_flags = val; + + return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS); +#else + return -EINVAL; +#endif +} + +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, +}; + static const struct bpf_func_proto * bpf_base_func_proto(enum bpf_func_id func_id) { @@ -3510,6 +3577,8 @@ static const struct bpf_func_proto * 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; default: @@ -3826,34 +3895,44 @@ void bpf_warn_invalid_xdp_action(u32 act) } EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action); -static bool __is_valid_sock_ops_access(int off, int size) +static bool sock_ops_is_valid_access(int off, int size, + enum bpf_access_type type, + 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 (size != sizeof(__u32)) - return false; - return true; -} - -static bool sock_ops_is_valid_access(int off, int size, - enum bpf_access_type type, - struct bpf_insn_access_aux *info) -{ if (type == BPF_WRITE) { switch (off) { - case offsetof(struct bpf_sock_ops, op) ... - offsetof(struct bpf_sock_ops, replylong[3]): + 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 __is_valid_sock_ops_access(off, size); + return true; } static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write, @@ -4470,10 +4549,37 @@ static u32 sock_ops_convert_ctx_access(enum bpf_access_type type, is_fullsock)); break; -/* Helper macro for adding read access to tcp_sock fields. */ -#define SOCK_OPS_GET_TCP32(FIELD_NAME) \ + 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(struct tcp_sock, FIELD_NAME) != 4); \ + 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), \ @@ -4485,17 +4591,159 @@ static u32 sock_ops_convert_ctx_access(enum bpf_access_type type, 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, FIELD_NAME)); \ + *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_TCP32(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_TCP32(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; } diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index d7cf861bf699f..f013ddc191e0c 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -463,7 +463,7 @@ void tcp_init_transfer(struct sock *sk, int bpf_op) tcp_mtup_init(sk); icsk->icsk_af_ops->rebuild_header(sk); tcp_init_metrics(sk); - tcp_call_bpf(sk, bpf_op); + tcp_call_bpf(sk, bpf_op, 0, NULL); tcp_init_congestion_control(sk); tcp_init_buffer_space(sk); } @@ -2042,6 +2042,30 @@ void tcp_set_state(struct sock *sk, int state) { int oldstate = sk->sk_state; + /* We defined a new enum for TCP states that are exported in BPF + * so as not force the internal TCP states to be frozen. The + * following checks will detect if an internal state value ever + * differs from the BPF value. If this ever happens, then we will + * need to remap the internal value to the BPF value before calling + * tcp_call_bpf_2arg. + */ + BUILD_BUG_ON((int)BPF_TCP_ESTABLISHED != (int)TCP_ESTABLISHED); + BUILD_BUG_ON((int)BPF_TCP_SYN_SENT != (int)TCP_SYN_SENT); + BUILD_BUG_ON((int)BPF_TCP_SYN_RECV != (int)TCP_SYN_RECV); + BUILD_BUG_ON((int)BPF_TCP_FIN_WAIT1 != (int)TCP_FIN_WAIT1); + BUILD_BUG_ON((int)BPF_TCP_FIN_WAIT2 != (int)TCP_FIN_WAIT2); + BUILD_BUG_ON((int)BPF_TCP_TIME_WAIT != (int)TCP_TIME_WAIT); + BUILD_BUG_ON((int)BPF_TCP_CLOSE != (int)TCP_CLOSE); + BUILD_BUG_ON((int)BPF_TCP_CLOSE_WAIT != (int)TCP_CLOSE_WAIT); + BUILD_BUG_ON((int)BPF_TCP_LAST_ACK != (int)TCP_LAST_ACK); + BUILD_BUG_ON((int)BPF_TCP_LISTEN != (int)TCP_LISTEN); + BUILD_BUG_ON((int)BPF_TCP_CLOSING != (int)TCP_CLOSING); + BUILD_BUG_ON((int)BPF_TCP_NEW_SYN_RECV != (int)TCP_NEW_SYN_RECV); + BUILD_BUG_ON((int)BPF_TCP_MAX_STATES != (int)TCP_MAX_STATES); + + if (BPF_SOCK_OPS_TEST_FLAG(tcp_sk(sk), BPF_SOCK_OPS_STATE_CB_FLAG)) + tcp_call_bpf_2arg(sk, BPF_SOCK_OPS_STATE_CB, oldstate, state); + switch (state) { case TCP_ESTABLISHED: if (oldstate != TCP_ESTABLISHED) diff --git a/net/ipv4/tcp_nv.c b/net/ipv4/tcp_nv.c index 0b5a05bd82e35..ddbce73edae89 100644 --- a/net/ipv4/tcp_nv.c +++ b/net/ipv4/tcp_nv.c @@ -146,7 +146,7 @@ static void tcpnv_init(struct sock *sk) * within a datacenter, where we have reasonable estimates of * RTTs */ - base_rtt = tcp_call_bpf(sk, BPF_SOCK_OPS_BASE_RTT); + base_rtt = tcp_call_bpf(sk, BPF_SOCK_OPS_BASE_RTT, 0, NULL); if (base_rtt > 0) { ca->nv_base_rtt = base_rtt; ca->nv_lower_bound_rtt = (base_rtt * 205) >> 8; /* 80% */ diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 95461f02ac9a2..e9f985e42405a 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2905,6 +2905,10 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs) err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC); } + if (BPF_SOCK_OPS_TEST_FLAG(tp, BPF_SOCK_OPS_RETRANS_CB_FLAG)) + tcp_call_bpf_3arg(sk, BPF_SOCK_OPS_RETRANS_CB, + TCP_SKB_CB(skb)->seq, segs, err); + if (likely(!err)) { TCP_SKB_CB(skb)->sacked |= TCPCB_EVER_RETRANS; trace_tcp_retransmit_skb(sk, skb); @@ -3469,7 +3473,7 @@ int tcp_connect(struct sock *sk) struct sk_buff *buff; int err; - tcp_call_bpf(sk, BPF_SOCK_OPS_TCP_CONNECT_CB); + tcp_call_bpf(sk, BPF_SOCK_OPS_TCP_CONNECT_CB, 0, NULL); if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk)) return -EHOSTUNREACH; /* Routing failure or similar. */ diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c index 6db3124cdbda9..257abdde23b0d 100644 --- a/net/ipv4/tcp_timer.c +++ b/net/ipv4/tcp_timer.c @@ -213,11 +213,18 @@ static int tcp_write_timeout(struct sock *sk) icsk->icsk_user_timeout); } tcp_fastopen_active_detect_blackhole(sk, expired); + + if (BPF_SOCK_OPS_TEST_FLAG(tp, BPF_SOCK_OPS_RTO_CB_FLAG)) + tcp_call_bpf_3arg(sk, BPF_SOCK_OPS_RTO_CB, + icsk->icsk_retransmits, + icsk->icsk_rto, (int)expired); + if (expired) { /* Has it gone just too far? */ tcp_write_err(sk); return 1; } + return 0; } diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index af1f49ad8b88d..db6bdc3751268 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -17,7 +17,7 @@ #define BPF_ALU64 0x07 /* alu mode in double word width */ /* ld/ldx fields */ -#define BPF_DW 0x18 /* double word */ +#define BPF_DW 0x18 /* double word (64-bit) */ #define BPF_XADD 0xc0 /* exclusive add */ /* alu/jmp fields */ @@ -642,6 +642,14 @@ union bpf_attr { * @optlen: length of optval in bytes * Return: 0 or negative error * + * int bpf_sock_ops_cb_flags_set(bpf_sock_ops, flags) + * Set callback flags for sock_ops + * @bpf_sock_ops: pointer to bpf_sock_ops_kern struct + * @flags: flags value + * Return: 0 for no error + * -EINVAL if there is no full tcp socket + * bits in flags that are not supported by current kernel + * * int bpf_skb_adjust_room(skb, len_diff, mode, flags) * Grow or shrink room in sk_buff. * @skb: pointer to skb @@ -748,7 +756,8 @@ union bpf_attr { FN(perf_event_read_value), \ FN(perf_prog_read_value), \ FN(getsockopt), \ - FN(override_return), + FN(override_return), \ + FN(sock_ops_cb_flags_set), /* integer value in 'imm' field of BPF_CALL instruction selects which helper * function eBPF program intends to call @@ -952,8 +961,9 @@ struct bpf_map_info { struct bpf_sock_ops { __u32 op; union { - __u32 reply; - __u32 replylong[4]; + __u32 args[4]; /* Optionally passed to bpf program */ + __u32 reply; /* Returned by bpf program */ + __u32 replylong[4]; /* Optionally returned by bpf prog */ }; __u32 family; __u32 remote_ip4; /* Stored in network byte order */ @@ -968,8 +978,39 @@ struct bpf_sock_ops { */ __u32 snd_cwnd; __u32 srtt_us; /* Averaged RTT << 3 in usecs */ + __u32 bpf_sock_ops_cb_flags; /* flags defined in uapi/linux/tcp.h */ + __u32 state; + __u32 rtt_min; + __u32 snd_ssthresh; + __u32 rcv_nxt; + __u32 snd_nxt; + __u32 snd_una; + __u32 mss_cache; + __u32 ecn_flags; + __u32 rate_delivered; + __u32 rate_interval_us; + __u32 packets_out; + __u32 retrans_out; + __u32 total_retrans; + __u32 segs_in; + __u32 data_segs_in; + __u32 segs_out; + __u32 data_segs_out; + __u32 lost_out; + __u32 sacked_out; + __u32 sk_txhash; + __u64 bytes_received; + __u64 bytes_acked; }; +/* Definitions for bpf_sock_ops_cb_flags */ +#define BPF_SOCK_OPS_RTO_CB_FLAG (1<<0) +#define BPF_SOCK_OPS_RETRANS_CB_FLAG (1<<1) +#define BPF_SOCK_OPS_STATE_CB_FLAG (1<<2) +#define BPF_SOCK_OPS_ALL_CB_FLAGS 0x7 /* Mask of all currently + * supported cb flags + */ + /* List of known BPF sock_ops operators. * New entries can only be added at the end */ @@ -1003,6 +1044,43 @@ enum { * a congestion threshold. RTTs above * this indicate congestion */ + BPF_SOCK_OPS_RTO_CB, /* Called when an RTO has triggered. + * Arg1: value of icsk_retransmits + * Arg2: value of icsk_rto + * Arg3: whether RTO has expired + */ + BPF_SOCK_OPS_RETRANS_CB, /* Called when skb is retransmitted. + * Arg1: sequence number of 1st byte + * Arg2: # segments + * Arg3: return value of + * tcp_transmit_skb (0 => success) + */ + BPF_SOCK_OPS_STATE_CB, /* Called when TCP changes state. + * Arg1: old_state + * Arg2: new_state + */ +}; + +/* List of TCP states. There is a build check in net/ipv4/tcp.c to detect + * changes between the TCP and BPF versions. Ideally this should never happen. + * If it does, we need to add code to convert them before calling + * the BPF sock_ops function. + */ +enum { + BPF_TCP_ESTABLISHED = 1, + BPF_TCP_SYN_SENT, + BPF_TCP_SYN_RECV, + BPF_TCP_FIN_WAIT1, + BPF_TCP_FIN_WAIT2, + BPF_TCP_TIME_WAIT, + BPF_TCP_CLOSE, + BPF_TCP_CLOSE_WAIT, + BPF_TCP_LAST_ACK, + BPF_TCP_LISTEN, + BPF_TCP_CLOSING, /* Now a valid state */ + BPF_TCP_NEW_SYN_RECV, + + BPF_TCP_MAX_STATES /* Leave at the end! */ }; #define TCP_BPF_IW 1001 /* Set TCP initial congestion window */ diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 3a44b655d852d..98688352208b5 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -14,13 +14,13 @@ CFLAGS += -Wall -O2 -I$(APIDIR) -I$(LIBDIR) -I$(GENDIR) $(GENFLAGS) -I../../../i LDLIBS += -lcap -lelf -lrt TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \ - test_align test_verifier_log test_dev_cgroup + test_align test_verifier_log test_dev_cgroup test_tcpbpf_user TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test_obj_id.o \ test_pkt_md_access.o test_xdp_redirect.o test_xdp_meta.o sockmap_parse_prog.o \ sockmap_verdict_prog.o dev_cgroup.o sample_ret0.o test_tracepoint.o \ test_l4lb_noinline.o test_xdp_noinline.o test_stacktrace_map.o \ - sample_map_ret0.o + sample_map_ret0.o test_tcpbpf_kern.o TEST_PROGS := test_kmod.sh test_xdp_redirect.sh test_xdp_meta.sh \ test_offload.py diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h index 33cb00e46c49f..dde2c11d77710 100644 --- a/tools/testing/selftests/bpf/bpf_helpers.h +++ b/tools/testing/selftests/bpf/bpf_helpers.h @@ -71,6 +71,8 @@ static int (*bpf_setsockopt)(void *ctx, int level, int optname, void *optval, static int (*bpf_getsockopt)(void *ctx, int level, int optname, void *optval, int optlen) = (void *) BPF_FUNC_getsockopt; +static int (*bpf_sock_ops_cb_flags_set)(void *ctx, int flags) = + (void *) BPF_FUNC_sock_ops_cb_flags_set; static int (*bpf_sk_redirect_map)(void *ctx, void *map, int key, int flags) = (void *) BPF_FUNC_sk_redirect_map; static int (*bpf_sock_map_update)(void *map, void *key, void *value, diff --git a/tools/testing/selftests/bpf/tcp_client.py b/tools/testing/selftests/bpf/tcp_client.py new file mode 100755 index 0000000000000..481dccdf140ce --- /dev/null +++ b/tools/testing/selftests/bpf/tcp_client.py @@ -0,0 +1,51 @@ +#!/usr/bin/env python2 +# +# SPDX-License-Identifier: GPL-2.0 +# + +import sys, os, os.path, getopt +import socket, time +import subprocess +import select + +def read(sock, n): + buf = '' + while len(buf) < n: + rem = n - len(buf) + try: s = sock.recv(rem) + except (socket.error), e: return '' + buf += s + return buf + +def send(sock, s): + total = len(s) + count = 0 + while count < total: + try: n = sock.send(s) + except (socket.error), e: n = 0 + if n == 0: + return count; + count += n + return count + + +serverPort = int(sys.argv[1]) +HostName = socket.gethostname() + +# create active socket +sock = socket.socket(socket.AF_INET6, socket.SOCK_STREAM) +try: + sock.connect((HostName, serverPort)) +except socket.error as e: + sys.exit(1) + +buf = '' +n = 0 +while n < 1000: + buf += '+' + n += 1 + +sock.settimeout(1); +n = send(sock, buf) +n = read(sock, 500) +sys.exit(0) diff --git a/tools/testing/selftests/bpf/tcp_server.py b/tools/testing/selftests/bpf/tcp_server.py new file mode 100755 index 0000000000000..bc454d7d0be21 --- /dev/null +++ b/tools/testing/selftests/bpf/tcp_server.py @@ -0,0 +1,83 @@ +#!/usr/bin/env python2 +# +# SPDX-License-Identifier: GPL-2.0 +# + +import sys, os, os.path, getopt +import socket, time +import subprocess +import select + +def read(sock, n): + buf = '' + while len(buf) < n: + rem = n - len(buf) + try: s = sock.recv(rem) + except (socket.error), e: return '' + buf += s + return buf + +def send(sock, s): + total = len(s) + count = 0 + while count < total: + try: n = sock.send(s) + except (socket.error), e: n = 0 + if n == 0: + return count; + count += n + return count + + +SERVER_PORT = 12877 +MAX_PORTS = 2 + +serverPort = SERVER_PORT +serverSocket = None + +HostName = socket.gethostname() + +# create passive socket +serverSocket = socket.socket(socket.AF_INET6, socket.SOCK_STREAM) +host = socket.gethostname() + +try: serverSocket.bind((host, 0)) +except socket.error as msg: + print 'bind fails: ', msg + +sn = serverSocket.getsockname() +serverPort = sn[1] + +cmdStr = ("./tcp_client.py %d &") % (serverPort) +os.system(cmdStr) + +buf = '' +n = 0 +while n < 500: + buf += '.' + n += 1 + +serverSocket.listen(MAX_PORTS) +readList = [serverSocket] + +while True: + readyRead, readyWrite, inError = \ + select.select(readList, [], [], 2) + + if len(readyRead) > 0: + waitCount = 0 + for sock in readyRead: + if sock == serverSocket: + (clientSocket, address) = serverSocket.accept() + address = str(address[0]) + readList.append(clientSocket) + else: + sock.settimeout(1); + s = read(sock, 1000) + n = send(sock, buf) + sock.close() + serverSocket.close() + sys.exit(0) + else: + print 'Select timeout!' + sys.exit(1) diff --git a/tools/testing/selftests/bpf/test_tcpbpf.h b/tools/testing/selftests/bpf/test_tcpbpf.h new file mode 100644 index 0000000000000..2fe43289943c7 --- /dev/null +++ b/tools/testing/selftests/bpf/test_tcpbpf.h @@ -0,0 +1,16 @@ +// SPDX-License-Identifier: GPL-2.0 + +#ifndef _TEST_TCPBPF_H +#define _TEST_TCPBPF_H + +struct tcpbpf_globals { + __u32 event_map; + __u32 total_retrans; + __u32 data_segs_in; + __u32 data_segs_out; + __u32 bad_cb_test_rv; + __u32 good_cb_test_rv; + __u64 bytes_received; + __u64 bytes_acked; +}; +#endif diff --git a/tools/testing/selftests/bpf/test_tcpbpf_kern.c b/tools/testing/selftests/bpf/test_tcpbpf_kern.c new file mode 100644 index 0000000000000..66bf71541903f --- /dev/null +++ b/tools/testing/selftests/bpf/test_tcpbpf_kern.c @@ -0,0 +1,118 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "bpf_helpers.h" +#include "bpf_endian.h" +#include "test_tcpbpf.h" + +struct bpf_map_def SEC("maps") global_map = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(__u32), + .value_size = sizeof(struct tcpbpf_globals), + .max_entries = 2, +}; + +static inline void update_event_map(int event) +{ + __u32 key = 0; + struct tcpbpf_globals g, *gp; + + gp = bpf_map_lookup_elem(&global_map, &key); + if (gp == NULL) { + struct tcpbpf_globals g = {0}; + + g.event_map |= (1 << event); + bpf_map_update_elem(&global_map, &key, &g, + BPF_ANY); + } else { + g = *gp; + g.event_map |= (1 << event); + bpf_map_update_elem(&global_map, &key, &g, + BPF_ANY); + } +} + +int _version SEC("version") = 1; + +SEC("sockops") +int bpf_testcb(struct bpf_sock_ops *skops) +{ + int rv = -1; + int bad_call_rv = 0; + int good_call_rv = 0; + int op; + int v = 0; + + op = (int) skops->op; + + update_event_map(op); + + switch (op) { + case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB: + /* Test failure to set largest cb flag (assumes not defined) */ + bad_call_rv = bpf_sock_ops_cb_flags_set(skops, 0x80); + /* Set callback */ + good_call_rv = bpf_sock_ops_cb_flags_set(skops, + BPF_SOCK_OPS_STATE_CB_FLAG); + /* Update results */ + { + __u32 key = 0; + struct tcpbpf_globals g, *gp; + + gp = bpf_map_lookup_elem(&global_map, &key); + if (!gp) + break; + g = *gp; + g.bad_cb_test_rv = bad_call_rv; + g.good_cb_test_rv = good_call_rv; + bpf_map_update_elem(&global_map, &key, &g, + BPF_ANY); + } + break; + case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB: + /* Set callback */ +// good_call_rv = bpf_sock_ops_cb_flags_set(skops, +// BPF_SOCK_OPS_STATE_CB_FLAG); + skops->sk_txhash = 0x12345f; + v = 0xff; + rv = bpf_setsockopt(skops, SOL_IPV6, IPV6_TCLASS, &v, + sizeof(v)); + break; + case BPF_SOCK_OPS_RTO_CB: + break; + case BPF_SOCK_OPS_RETRANS_CB: + break; + case BPF_SOCK_OPS_STATE_CB: + if (skops->args[1] == BPF_TCP_CLOSE) { + __u32 key = 0; + struct tcpbpf_globals g, *gp; + + gp = bpf_map_lookup_elem(&global_map, &key); + if (!gp) + break; + g = *gp; + g.total_retrans = skops->total_retrans; + g.data_segs_in = skops->data_segs_in; + g.data_segs_out = skops->data_segs_out; + g.bytes_received = skops->bytes_received; + g.bytes_acked = skops->bytes_acked; + bpf_map_update_elem(&global_map, &key, &g, + BPF_ANY); + } + break; + default: + rv = -1; + } + skops->reply = rv; + return 1; +} +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/test_tcpbpf_user.c b/tools/testing/selftests/bpf/test_tcpbpf_user.c new file mode 100644 index 0000000000000..95a370f3d3784 --- /dev/null +++ b/tools/testing/selftests/bpf/test_tcpbpf_user.c @@ -0,0 +1,126 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "bpf_util.h" +#include +#include "test_tcpbpf.h" + +static int bpf_find_map(const char *test, struct bpf_object *obj, + const char *name) +{ + struct bpf_map *map; + + map = bpf_object__find_map_by_name(obj, name); + if (!map) { + printf("%s:FAIL:map '%s' not found\n", test, name); + return -1; + } + return bpf_map__fd(map); +} + +#define SYSTEM(CMD) \ + do { \ + if (system(CMD)) { \ + printf("system(%s) FAILS!\n", CMD); \ + } \ + } while (0) + +int main(int argc, char **argv) +{ + const char *file = "test_tcpbpf_kern.o"; + struct tcpbpf_globals g = {0}; + int cg_fd, prog_fd, map_fd; + bool debug_flag = false; + int error = EXIT_FAILURE; + struct bpf_object *obj; + char cmd[100], *dir; + struct stat buffer; + __u32 key = 0; + int pid; + int rv; + + if (argc > 1 && strcmp(argv[1], "-d") == 0) + debug_flag = true; + + dir = "/tmp/cgroupv2/foo"; + + if (stat(dir, &buffer) != 0) { + SYSTEM("mkdir -p /tmp/cgroupv2"); + SYSTEM("mount -t cgroup2 none /tmp/cgroupv2"); + SYSTEM("mkdir -p /tmp/cgroupv2/foo"); + } + pid = (int) getpid(); + sprintf(cmd, "echo %d >> /tmp/cgroupv2/foo/cgroup.procs", pid); + SYSTEM(cmd); + + cg_fd = open(dir, O_DIRECTORY, O_RDONLY); + if (bpf_prog_load(file, BPF_PROG_TYPE_SOCK_OPS, &obj, &prog_fd)) { + printf("FAILED: load_bpf_file failed for: %s\n", file); + goto err; + } + + rv = bpf_prog_attach(prog_fd, cg_fd, BPF_CGROUP_SOCK_OPS, 0); + if (rv) { + printf("FAILED: bpf_prog_attach: %d (%s)\n", + error, strerror(errno)); + goto err; + } + + SYSTEM("./tcp_server.py"); + + map_fd = bpf_find_map(__func__, obj, "global_map"); + if (map_fd < 0) + goto err; + + rv = bpf_map_lookup_elem(map_fd, &key, &g); + if (rv != 0) { + printf("FAILED: bpf_map_lookup_elem returns %d\n", rv); + goto err; + } + + if (g.bytes_received != 501 || g.bytes_acked != 1002 || + g.data_segs_in != 1 || g.data_segs_out != 1 || + (g.event_map ^ 0x47e) != 0 || g.bad_cb_test_rv != 0x80 || + g.good_cb_test_rv != 0) { + printf("FAILED: Wrong stats\n"); + if (debug_flag) { + printf("\n"); + printf("bytes_received: %d (expecting 501)\n", + (int)g.bytes_received); + printf("bytes_acked: %d (expecting 1002)\n", + (int)g.bytes_acked); + printf("data_segs_in: %d (expecting 1)\n", + g.data_segs_in); + printf("data_segs_out: %d (expecting 1)\n", + g.data_segs_out); + printf("event_map: 0x%x (at least 0x47e)\n", + g.event_map); + printf("bad_cb_test_rv: 0x%x (expecting 0x80)\n", + g.bad_cb_test_rv); + printf("good_cb_test_rv:0x%x (expecting 0)\n", + g.good_cb_test_rv); + } + goto err; + } + printf("PASSED!\n"); + error = 0; +err: + bpf_prog_detach(cg_fd, BPF_CGROUP_SOCK_OPS); + return error; + +}