From 1b66d253610c7f8f257103808a9460223a087469 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Tue, 19 May 2020 00:45:45 +0200 Subject: [PATCH 1/4] bpf: Add get{peer, sock}name attach types for sock_addr As stated in 983695fa6765 ("bpf: fix unconnected udp hooks"), the objective for the existing cgroup connect/sendmsg/recvmsg/bind BPF hooks is to be transparent to applications. In Cilium we make use of these hooks [0] in order to enable E-W load balancing for existing Kubernetes service types for all Cilium managed nodes in the cluster. Those backends can be local or remote. The main advantage of this approach is that it operates as close as possible to the socket, and therefore allows to avoid packet-based NAT given in connect/sendmsg/recvmsg hooks we only need to xlate sock addresses. This also allows to expose NodePort services on loopback addresses in the host namespace, for example. As another advantage, this also efficiently blocks bind requests for applications in the host namespace for exposed ports. However, one missing item is that we also need to perform reverse xlation for inet{,6}_getname() hooks such that we can return the service IP/port tuple back to the application instead of the remote peer address. The vast majority of applications does not bother about getpeername(), but in a few occasions we've seen breakage when validating the peer's address since it returns unexpectedly the backend tuple instead of the service one. Therefore, this trivial patch allows to customise and adds a getpeername() as well as getsockname() BPF cgroup hook for both IPv4 and IPv6 in order to address this situation. Simple example: # ./cilium/cilium service list ID Frontend Service Type Backend 1 1.2.3.4:80 ClusterIP 1 => 10.0.0.10:80 Before; curl's verbose output example, no getpeername() reverse xlation: # curl --verbose 1.2.3.4 * Rebuilt URL to: 1.2.3.4/ * Trying 1.2.3.4... * TCP_NODELAY set * Connected to 1.2.3.4 (10.0.0.10) port 80 (#0) > GET / HTTP/1.1 > Host: 1.2.3.4 > User-Agent: curl/7.58.0 > Accept: */* [...] After; with getpeername() reverse xlation: # curl --verbose 1.2.3.4 * Rebuilt URL to: 1.2.3.4/ * Trying 1.2.3.4... * TCP_NODELAY set * Connected to 1.2.3.4 (1.2.3.4) port 80 (#0) > GET / HTTP/1.1 > Host: 1.2.3.4 > User-Agent: curl/7.58.0 > Accept: */* [...] Originally, I had both under a BPF_CGROUP_INET{4,6}_GETNAME type and exposed peer to the context similar as in inet{,6}_getname() fashion, but API-wise this is suboptimal as it always enforces programs having to test for ctx->peer which can easily be missed, hence BPF_CGROUP_INET{4,6}_GET{PEER,SOCK}NAME split. Similarly, the checked return code is on tnum_range(1, 1), but if a use case comes up in future, it can easily be changed to return an error code instead. Helper and ctx member access is the same as with connect/sendmsg/etc hooks. [0] https://github.com/cilium/cilium/blob/master/bpf/bpf_sock.c Signed-off-by: Daniel Borkmann Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Acked-by: Andrey Ignatov Link: https://lore.kernel.org/bpf/61a479d759b2482ae3efb45546490bacd796a220.1589841594.git.daniel@iogearbox.net --- include/linux/bpf-cgroup.h | 1 + include/uapi/linux/bpf.h | 4 ++++ kernel/bpf/syscall.c | 12 ++++++++++++ kernel/bpf/verifier.c | 6 +++++- net/core/filter.c | 4 ++++ net/ipv4/af_inet.c | 8 ++++++-- net/ipv6/af_inet6.c | 9 ++++++--- tools/include/uapi/linux/bpf.h | 4 ++++ 8 files changed, 42 insertions(+), 6 deletions(-) diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h index 272626cc3fc9d..c66c545e161a6 100644 --- a/include/linux/bpf-cgroup.h +++ b/include/linux/bpf-cgroup.h @@ -396,6 +396,7 @@ static inline int bpf_percpu_cgroup_storage_update(struct bpf_map *map, } #define cgroup_bpf_enabled (0) +#define BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, type, t_ctx) ({ 0; }) #define BPF_CGROUP_PRE_CONNECT_ENABLED(sk) (0) #define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk,skb) ({ 0; }) #define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk,skb) ({ 0; }) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index b9b8a0f63b913..97e1fd19ff58a 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -220,6 +220,10 @@ enum bpf_attach_type { BPF_MODIFY_RETURN, BPF_LSM_MAC, BPF_TRACE_ITER, + BPF_CGROUP_INET4_GETPEERNAME, + BPF_CGROUP_INET6_GETPEERNAME, + BPF_CGROUP_INET4_GETSOCKNAME, + BPF_CGROUP_INET6_GETSOCKNAME, __MAX_BPF_ATTACH_TYPE }; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 57dfc98289d53..431241c746143 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1978,6 +1978,10 @@ bpf_prog_load_check_attach(enum bpf_prog_type prog_type, case BPF_CGROUP_INET6_BIND: case BPF_CGROUP_INET4_CONNECT: case BPF_CGROUP_INET6_CONNECT: + case BPF_CGROUP_INET4_GETPEERNAME: + case BPF_CGROUP_INET6_GETPEERNAME: + case BPF_CGROUP_INET4_GETSOCKNAME: + case BPF_CGROUP_INET6_GETSOCKNAME: case BPF_CGROUP_UDP4_SENDMSG: case BPF_CGROUP_UDP6_SENDMSG: case BPF_CGROUP_UDP4_RECVMSG: @@ -2767,6 +2771,10 @@ attach_type_to_prog_type(enum bpf_attach_type attach_type) case BPF_CGROUP_INET6_BIND: case BPF_CGROUP_INET4_CONNECT: case BPF_CGROUP_INET6_CONNECT: + case BPF_CGROUP_INET4_GETPEERNAME: + case BPF_CGROUP_INET6_GETPEERNAME: + case BPF_CGROUP_INET4_GETSOCKNAME: + case BPF_CGROUP_INET6_GETSOCKNAME: case BPF_CGROUP_UDP4_SENDMSG: case BPF_CGROUP_UDP6_SENDMSG: case BPF_CGROUP_UDP4_RECVMSG: @@ -2912,6 +2920,10 @@ static int bpf_prog_query(const union bpf_attr *attr, case BPF_CGROUP_INET6_POST_BIND: case BPF_CGROUP_INET4_CONNECT: case BPF_CGROUP_INET6_CONNECT: + case BPF_CGROUP_INET4_GETPEERNAME: + case BPF_CGROUP_INET6_GETPEERNAME: + case BPF_CGROUP_INET4_GETSOCKNAME: + case BPF_CGROUP_INET6_GETSOCKNAME: case BPF_CGROUP_UDP4_SENDMSG: case BPF_CGROUP_UDP6_SENDMSG: case BPF_CGROUP_UDP4_RECVMSG: diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 9c7d67d65d8cc..2ed8351f47a49 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -7094,7 +7094,11 @@ static int check_return_code(struct bpf_verifier_env *env) switch (env->prog->type) { case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: if (env->prog->expected_attach_type == BPF_CGROUP_UDP4_RECVMSG || - env->prog->expected_attach_type == BPF_CGROUP_UDP6_RECVMSG) + env->prog->expected_attach_type == BPF_CGROUP_UDP6_RECVMSG || + env->prog->expected_attach_type == BPF_CGROUP_INET4_GETPEERNAME || + env->prog->expected_attach_type == BPF_CGROUP_INET6_GETPEERNAME || + env->prog->expected_attach_type == BPF_CGROUP_INET4_GETSOCKNAME || + env->prog->expected_attach_type == BPF_CGROUP_INET6_GETSOCKNAME) range = tnum_range(1, 1); break; case BPF_PROG_TYPE_CGROUP_SKB: diff --git a/net/core/filter.c b/net/core/filter.c index 822d662f97ef9..bd2853d23b505 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -7049,6 +7049,8 @@ static bool sock_addr_is_valid_access(int off, int size, switch (prog->expected_attach_type) { case BPF_CGROUP_INET4_BIND: case BPF_CGROUP_INET4_CONNECT: + case BPF_CGROUP_INET4_GETPEERNAME: + case BPF_CGROUP_INET4_GETSOCKNAME: case BPF_CGROUP_UDP4_SENDMSG: case BPF_CGROUP_UDP4_RECVMSG: break; @@ -7060,6 +7062,8 @@ static bool sock_addr_is_valid_access(int off, int size, switch (prog->expected_attach_type) { case BPF_CGROUP_INET6_BIND: case BPF_CGROUP_INET6_CONNECT: + case BPF_CGROUP_INET6_GETPEERNAME: + case BPF_CGROUP_INET6_GETSOCKNAME: case BPF_CGROUP_UDP6_SENDMSG: case BPF_CGROUP_UDP6_RECVMSG: break; diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index fcf0d12a407a9..8f5c8c9409d39 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -755,12 +755,11 @@ int inet_accept(struct socket *sock, struct socket *newsock, int flags, } EXPORT_SYMBOL(inet_accept); - /* * This does both peername and sockname. */ int inet_getname(struct socket *sock, struct sockaddr *uaddr, - int peer) + int peer) { struct sock *sk = sock->sk; struct inet_sock *inet = inet_sk(sk); @@ -781,6 +780,11 @@ int inet_getname(struct socket *sock, struct sockaddr *uaddr, sin->sin_port = inet->inet_sport; sin->sin_addr.s_addr = addr; } + if (cgroup_bpf_enabled) + BPF_CGROUP_RUN_SA_PROG_LOCK(sk, (struct sockaddr *)sin, + peer ? BPF_CGROUP_INET4_GETPEERNAME : + BPF_CGROUP_INET4_GETSOCKNAME, + NULL); memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); return sizeof(*sin); } diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index 771a462a8322b..3b6fcc0c321ae 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -504,9 +504,8 @@ EXPORT_SYMBOL_GPL(inet6_destroy_sock); /* * This does both peername and sockname. */ - int inet6_getname(struct socket *sock, struct sockaddr *uaddr, - int peer) + int peer) { struct sockaddr_in6 *sin = (struct sockaddr_in6 *)uaddr; struct sock *sk = sock->sk; @@ -531,9 +530,13 @@ int inet6_getname(struct socket *sock, struct sockaddr *uaddr, sin->sin6_addr = np->saddr; else sin->sin6_addr = sk->sk_v6_rcv_saddr; - sin->sin6_port = inet->inet_sport; } + if (cgroup_bpf_enabled) + BPF_CGROUP_RUN_SA_PROG_LOCK(sk, (struct sockaddr *)sin, + peer ? BPF_CGROUP_INET6_GETPEERNAME : + BPF_CGROUP_INET6_GETSOCKNAME, + NULL); sin->sin6_scope_id = ipv6_iface_scope_id(&sin->sin6_addr, sk->sk_bound_dev_if); return sizeof(*sin); diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 146c742f1d491..1cddc398404a8 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -220,6 +220,10 @@ enum bpf_attach_type { BPF_MODIFY_RETURN, BPF_LSM_MAC, BPF_TRACE_ITER, + BPF_CGROUP_INET4_GETPEERNAME, + BPF_CGROUP_INET6_GETPEERNAME, + BPF_CGROUP_INET4_GETSOCKNAME, + BPF_CGROUP_INET6_GETSOCKNAME, __MAX_BPF_ATTACH_TYPE }; From f15ed0185de7d471e907783739dffbe397a93142 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Tue, 19 May 2020 00:45:46 +0200 Subject: [PATCH 2/4] bpf, libbpf: Enable get{peer, sock}name attach types Trivial patch to add the new get{peer,sock}name attach types to the section definitions in order to hook them up to sock_addr cgroup program type. Signed-off-by: Daniel Borkmann Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Acked-by: Andrey Ignatov Link: https://lore.kernel.org/bpf/7fcd4b1e41a8ebb364754a5975c75a7795051bd2.1589841594.git.daniel@iogearbox.net --- tools/lib/bpf/libbpf.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 2922579954877..fa04cbe547ed8 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -6705,6 +6705,14 @@ static const struct bpf_sec_def section_defs[] = { BPF_CGROUP_UDP4_RECVMSG), BPF_EAPROG_SEC("cgroup/recvmsg6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_UDP6_RECVMSG), + BPF_EAPROG_SEC("cgroup/getpeername4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, + BPF_CGROUP_INET4_GETPEERNAME), + BPF_EAPROG_SEC("cgroup/getpeername6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, + BPF_CGROUP_INET6_GETPEERNAME), + BPF_EAPROG_SEC("cgroup/getsockname4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, + BPF_CGROUP_INET4_GETSOCKNAME), + BPF_EAPROG_SEC("cgroup/getsockname6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, + BPF_CGROUP_INET6_GETSOCKNAME), BPF_EAPROG_SEC("cgroup/sysctl", BPF_PROG_TYPE_CGROUP_SYSCTL, BPF_CGROUP_SYSCTL), BPF_EAPROG_SEC("cgroup/getsockopt", BPF_PROG_TYPE_CGROUP_SOCKOPT, From 05ee19c18c2bb3dea69e29219017367c4a77e65a Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Tue, 19 May 2020 00:45:47 +0200 Subject: [PATCH 3/4] bpf, bpftool: Enable get{peer, sock}name attach types Make bpftool aware and add the new get{peer,sock}name attach types to its cli, documentation and bash completion to allow attachment/detachment of sock_addr programs there. Signed-off-by: Daniel Borkmann Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Acked-by: Andrey Ignatov Link: https://lore.kernel.org/bpf/9765b3d03e4c29210c4df56a9cc7e52f5f7bb5ef.1589841594.git.daniel@iogearbox.net --- .../bpf/bpftool/Documentation/bpftool-cgroup.rst | 10 +++++++--- tools/bpf/bpftool/Documentation/bpftool-prog.rst | 3 ++- tools/bpf/bpftool/bash-completion/bpftool | 15 +++++++++------ tools/bpf/bpftool/cgroup.c | 7 ++++--- tools/bpf/bpftool/main.h | 4 ++++ tools/bpf/bpftool/prog.c | 6 ++++-- 6 files changed, 30 insertions(+), 15 deletions(-) diff --git a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst index e4d9da654e842..a226aee3574fd 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-cgroup.rst @@ -29,8 +29,8 @@ CGROUP COMMANDS | *PROG* := { **id** *PROG_ID* | **pinned** *FILE* | **tag** *PROG_TAG* } | *ATTACH_TYPE* := { **ingress** | **egress** | **sock_create** | **sock_ops** | **device** | | **bind4** | **bind6** | **post_bind4** | **post_bind6** | **connect4** | **connect6** | -| **sendmsg4** | **sendmsg6** | **recvmsg4** | **recvmsg6** | **sysctl** | -| **getsockopt** | **setsockopt** } +| **getpeername4** | **getpeername6** | **getsockname4** | **getsockname6** | **sendmsg4** | +| **sendmsg6** | **recvmsg4** | **recvmsg6** | **sysctl** | **getsockopt** | **setsockopt** } | *ATTACH_FLAGS* := { **multi** | **override** } DESCRIPTION @@ -101,7 +101,11 @@ DESCRIPTION an unconnected udp6 socket (since 5.2); **sysctl** sysctl access (since 5.2); **getsockopt** call to getsockopt (since 5.3); - **setsockopt** call to setsockopt (since 5.3). + **setsockopt** call to setsockopt (since 5.3); + **getpeername4** call to getpeername(2) for an inet4 socket (since 5.8); + **getpeername6** call to getpeername(2) for an inet6 socket (since 5.8); + **getsockname4** call to getsockname(2) for an inet4 socket (since 5.8); + **getsockname6** call to getsockname(2) for an inet6 socket (since 5.8). **bpftool cgroup detach** *CGROUP* *ATTACH_TYPE* *PROG* Detach *PROG* from the cgroup *CGROUP* and attach type diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst index 5948e9d89c8d8..2b254959d4880 100644 --- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst +++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst @@ -41,7 +41,8 @@ PROG COMMANDS | **cgroup/sock** | **cgroup/dev** | **lwt_in** | **lwt_out** | **lwt_xmit** | | **lwt_seg6local** | **sockops** | **sk_skb** | **sk_msg** | **lirc_mode2** | | **cgroup/bind4** | **cgroup/bind6** | **cgroup/post_bind4** | **cgroup/post_bind6** | -| **cgroup/connect4** | **cgroup/connect6** | **cgroup/sendmsg4** | **cgroup/sendmsg6** | +| **cgroup/connect4** | **cgroup/connect6** | **cgroup/getpeername4** | **cgroup/getpeername6** | +| **cgroup/getsockname4** | **cgroup/getsockname6** | **cgroup/sendmsg4** | **cgroup/sendmsg6** | | **cgroup/recvmsg4** | **cgroup/recvmsg6** | **cgroup/sysctl** | | **cgroup/getsockopt** | **cgroup/setsockopt** | | **struct_ops** | **fentry** | **fexit** | **freplace** diff --git a/tools/bpf/bpftool/bash-completion/bpftool b/tools/bpf/bpftool/bash-completion/bpftool index 9f0f20e73b87a..25b25aca11120 100644 --- a/tools/bpf/bpftool/bash-completion/bpftool +++ b/tools/bpf/bpftool/bash-completion/bpftool @@ -472,6 +472,8 @@ _bpftool() lwt_seg6local sockops sk_skb sk_msg \ lirc_mode2 cgroup/bind4 cgroup/bind6 \ cgroup/connect4 cgroup/connect6 \ + cgroup/getpeername4 cgroup/getpeername6 \ + cgroup/getsockname4 cgroup/getsockname6 \ cgroup/sendmsg4 cgroup/sendmsg6 \ cgroup/recvmsg4 cgroup/recvmsg6 \ cgroup/post_bind4 cgroup/post_bind6 \ @@ -966,9 +968,10 @@ _bpftool() ;; attach|detach) local ATTACH_TYPES='ingress egress sock_create sock_ops \ - device bind4 bind6 post_bind4 post_bind6 connect4 \ - connect6 sendmsg4 sendmsg6 recvmsg4 recvmsg6 sysctl \ - getsockopt setsockopt' + device bind4 bind6 post_bind4 post_bind6 connect4 connect6 \ + getpeername4 getpeername6 getsockname4 getsockname6 \ + sendmsg4 sendmsg6 recvmsg4 recvmsg6 sysctl getsockopt \ + setsockopt' local ATTACH_FLAGS='multi override' local PROG_TYPE='id pinned tag name' case $prev in @@ -977,9 +980,9 @@ _bpftool() return 0 ;; ingress|egress|sock_create|sock_ops|device|bind4|bind6|\ - post_bind4|post_bind6|connect4|connect6|sendmsg4|\ - sendmsg6|recvmsg4|recvmsg6|sysctl|getsockopt|\ - setsockopt) + post_bind4|post_bind6|connect4|connect6|getpeername4|\ + getpeername6|getsockname4|getsockname6|sendmsg4|sendmsg6|\ + recvmsg4|recvmsg6|sysctl|getsockopt|setsockopt) COMPREPLY=( $( compgen -W "$PROG_TYPE" -- \ "$cur" ) ) return 0 diff --git a/tools/bpf/bpftool/cgroup.c b/tools/bpf/bpftool/cgroup.c index 1693c802bb207..27931db421d81 100644 --- a/tools/bpf/bpftool/cgroup.c +++ b/tools/bpf/bpftool/cgroup.c @@ -25,9 +25,10 @@ " ATTACH_TYPE := { ingress | egress | sock_create |\n" \ " sock_ops | device | bind4 | bind6 |\n" \ " post_bind4 | post_bind6 | connect4 |\n" \ - " connect6 | sendmsg4 | sendmsg6 |\n" \ - " recvmsg4 | recvmsg6 | sysctl |\n" \ - " getsockopt | setsockopt }" + " connect6 | getpeername4 | getpeername6 |\n" \ + " getsockname4 | getsockname6 | sendmsg4 |\n" \ + " sendmsg6 | recvmsg4 | recvmsg6 |\n" \ + " sysctl | getsockopt | setsockopt }" static unsigned int query_flags; diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index f89ac70ef973f..5cdf0bc049bd9 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h @@ -100,6 +100,10 @@ static const char * const attach_type_name[__MAX_BPF_ATTACH_TYPE] = { [BPF_CGROUP_INET6_CONNECT] = "connect6", [BPF_CGROUP_INET4_POST_BIND] = "post_bind4", [BPF_CGROUP_INET6_POST_BIND] = "post_bind6", + [BPF_CGROUP_INET4_GETPEERNAME] = "getpeername4", + [BPF_CGROUP_INET6_GETPEERNAME] = "getpeername6", + [BPF_CGROUP_INET4_GETSOCKNAME] = "getsockname4", + [BPF_CGROUP_INET6_GETSOCKNAME] = "getsockname6", [BPF_CGROUP_UDP4_SENDMSG] = "sendmsg4", [BPF_CGROUP_UDP6_SENDMSG] = "sendmsg6", [BPF_CGROUP_SYSCTL] = "sysctl", diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index b6e5ba568f98c..245f941fdbcf1 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -2012,8 +2012,10 @@ static int do_help(int argc, char **argv) " sk_reuseport | flow_dissector | cgroup/sysctl |\n" " cgroup/bind4 | cgroup/bind6 | cgroup/post_bind4 |\n" " cgroup/post_bind6 | cgroup/connect4 | cgroup/connect6 |\n" - " cgroup/sendmsg4 | cgroup/sendmsg6 | cgroup/recvmsg4 |\n" - " cgroup/recvmsg6 | cgroup/getsockopt | cgroup/setsockopt |\n" + " cgroup/getpeername4 | cgroup/getpeername6 |\n" + " cgroup/getsockname4 | cgroup/getsockname6 | cgroup/sendmsg4 |\n" + " cgroup/sendmsg6 | cgroup/recvmsg4 | cgroup/recvmsg6 |\n" + " cgroup/getsockopt | cgroup/setsockopt |\n" " struct_ops | fentry | fexit | freplace }\n" " ATTACH_TYPE := { msg_verdict | stream_verdict | stream_parser |\n" " flow_dissector }\n" From 566fc3f5d1c641b510ec487cf274a047f8a1e849 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Tue, 19 May 2020 00:45:48 +0200 Subject: [PATCH 4/4] bpf, testing: Add get{peer, sock}name selftests to test_progs Extend the existing connect_force_port test to assert get{peer,sock}name programs as well. The workflow for e.g. IPv4 is as follows: i) server binds to concrete port, ii) client calls getsockname() on server fd which exposes 1.2.3.4:60000 to client, iii) client connects to service address 1.2.3.4:60000 binds to concrete local address (127.0.0.1:22222) and remaps service address to a concrete backend address (127.0.0.1:60123), iv) client then calls getsockname() on its own fd to verify local address (127.0.0.1:22222) and getpeername() on its own fd which then publishes service address (1.2.3.4:60000) instead of actual backend. Same workflow is done for IPv6 just with different address/port tuples. # ./test_progs -t connect_force_port #14 connect_force_port:OK Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Daniel Borkmann Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Acked-by: Andrey Ignatov Link: https://lore.kernel.org/bpf/3343da6ad08df81af715a95d61a84fb4a960f2bf.1589841594.git.daniel@iogearbox.net --- tools/testing/selftests/bpf/network_helpers.c | 11 +- tools/testing/selftests/bpf/network_helpers.h | 1 + .../bpf/prog_tests/connect_force_port.c | 107 +++++++++++++----- .../selftests/bpf/progs/connect_force_port4.c | 59 +++++++++- .../selftests/bpf/progs/connect_force_port6.c | 70 +++++++++++- 5 files changed, 215 insertions(+), 33 deletions(-) diff --git a/tools/testing/selftests/bpf/network_helpers.c b/tools/testing/selftests/bpf/network_helpers.c index 999a775484c19..e36dd1a1780d8 100644 --- a/tools/testing/selftests/bpf/network_helpers.c +++ b/tools/testing/selftests/bpf/network_helpers.c @@ -5,6 +5,8 @@ #include #include +#include + #include #include @@ -35,7 +37,7 @@ struct ipv6_packet pkt_v6 = { .tcp.doff = 5, }; -int start_server(int family, int type) +int start_server_with_port(int family, int type, __u16 port) { struct sockaddr_storage addr = {}; socklen_t len; @@ -45,11 +47,13 @@ int start_server(int family, int type) struct sockaddr_in *sin = (void *)&addr; sin->sin_family = AF_INET; + sin->sin_port = htons(port); len = sizeof(*sin); } else { struct sockaddr_in6 *sin6 = (void *)&addr; sin6->sin6_family = AF_INET6; + sin6->sin6_port = htons(port); len = sizeof(*sin6); } @@ -76,6 +80,11 @@ int start_server(int family, int type) return fd; } +int start_server(int family, int type) +{ + return start_server_with_port(family, type, 0); +} + static const struct timeval timeo_sec = { .tv_sec = 3 }; static const size_t timeo_optlen = sizeof(timeo_sec); diff --git a/tools/testing/selftests/bpf/network_helpers.h b/tools/testing/selftests/bpf/network_helpers.h index 86914e6e7b535..6a8009605670c 100644 --- a/tools/testing/selftests/bpf/network_helpers.h +++ b/tools/testing/selftests/bpf/network_helpers.h @@ -34,6 +34,7 @@ struct ipv6_packet { extern struct ipv6_packet pkt_v6; int start_server(int family, int type); +int start_server_with_port(int family, int type, __u16 port); int connect_to_fd(int family, int type, int server_fd); int connect_fd_to_fd(int client_fd, int server_fd); int connect_wait(int client_fd); diff --git a/tools/testing/selftests/bpf/prog_tests/connect_force_port.c b/tools/testing/selftests/bpf/prog_tests/connect_force_port.c index 47fbb20cb6a66..17bbf76812ca5 100644 --- a/tools/testing/selftests/bpf/prog_tests/connect_force_port.c +++ b/tools/testing/selftests/bpf/prog_tests/connect_force_port.c @@ -4,7 +4,8 @@ #include "cgroup_helpers.h" #include "network_helpers.h" -static int verify_port(int family, int fd, int expected) +static int verify_ports(int family, int fd, + __u16 expected_local, __u16 expected_peer) { struct sockaddr_storage addr; socklen_t len = sizeof(addr); @@ -20,9 +21,25 @@ static int verify_port(int family, int fd, int expected) else port = ((struct sockaddr_in6 *)&addr)->sin6_port; - if (ntohs(port) != expected) { - log_err("Unexpected port %d, expected %d", ntohs(port), - expected); + if (ntohs(port) != expected_local) { + log_err("Unexpected local port %d, expected %d", ntohs(port), + expected_local); + return -1; + } + + if (getpeername(fd, (struct sockaddr *)&addr, &len)) { + log_err("Failed to get peer addr"); + return -1; + } + + if (family == AF_INET) + port = ((struct sockaddr_in *)&addr)->sin_port; + else + port = ((struct sockaddr_in6 *)&addr)->sin6_port; + + if (ntohs(port) != expected_peer) { + log_err("Unexpected peer port %d, expected %d", ntohs(port), + expected_peer); return -1; } @@ -31,33 +48,67 @@ static int verify_port(int family, int fd, int expected) static int run_test(int cgroup_fd, int server_fd, int family, int type) { + bool v4 = family == AF_INET; + __u16 expected_local_port = v4 ? 22222 : 22223; + __u16 expected_peer_port = 60000; struct bpf_prog_load_attr attr = { - .prog_type = BPF_PROG_TYPE_CGROUP_SOCK_ADDR, + .file = v4 ? "./connect_force_port4.o" : + "./connect_force_port6.o", }; + struct bpf_program *prog; struct bpf_object *obj; - int expected_port; - int prog_fd; - int err; - int fd; - - if (family == AF_INET) { - attr.file = "./connect_force_port4.o"; - attr.expected_attach_type = BPF_CGROUP_INET4_CONNECT; - expected_port = 22222; - } else { - attr.file = "./connect_force_port6.o"; - attr.expected_attach_type = BPF_CGROUP_INET6_CONNECT; - expected_port = 22223; - } + int xlate_fd, fd, err; + __u32 duration = 0; - err = bpf_prog_load_xattr(&attr, &obj, &prog_fd); + err = bpf_prog_load_xattr(&attr, &obj, &xlate_fd); if (err) { log_err("Failed to load BPF object"); return -1; } - err = bpf_prog_attach(prog_fd, cgroup_fd, attr.expected_attach_type, - 0); + prog = bpf_object__find_program_by_title(obj, v4 ? + "cgroup/connect4" : + "cgroup/connect6"); + if (CHECK(!prog, "find_prog", "connect prog not found\n")) { + err = -EIO; + goto close_bpf_object; + } + + err = bpf_prog_attach(bpf_program__fd(prog), cgroup_fd, v4 ? + BPF_CGROUP_INET4_CONNECT : + BPF_CGROUP_INET6_CONNECT, 0); + if (err) { + log_err("Failed to attach BPF program"); + goto close_bpf_object; + } + + prog = bpf_object__find_program_by_title(obj, v4 ? + "cgroup/getpeername4" : + "cgroup/getpeername6"); + if (CHECK(!prog, "find_prog", "getpeername prog not found\n")) { + err = -EIO; + goto close_bpf_object; + } + + err = bpf_prog_attach(bpf_program__fd(prog), cgroup_fd, v4 ? + BPF_CGROUP_INET4_GETPEERNAME : + BPF_CGROUP_INET6_GETPEERNAME, 0); + if (err) { + log_err("Failed to attach BPF program"); + goto close_bpf_object; + } + + prog = bpf_object__find_program_by_title(obj, v4 ? + "cgroup/getsockname4" : + "cgroup/getsockname6"); + if (CHECK(!prog, "find_prog", "getsockname prog not found\n")) { + err = -EIO; + goto close_bpf_object; + } + + err = bpf_prog_attach(bpf_program__fd(prog), cgroup_fd, v4 ? + BPF_CGROUP_INET4_GETSOCKNAME : + BPF_CGROUP_INET6_GETSOCKNAME, 0); if (err) { log_err("Failed to attach BPF program"); goto close_bpf_object; @@ -69,8 +120,8 @@ static int run_test(int cgroup_fd, int server_fd, int family, int type) goto close_bpf_object; } - err = verify_port(family, fd, expected_port); - + err = verify_ports(family, fd, expected_local_port, + expected_peer_port); close(fd); close_bpf_object: @@ -86,25 +137,25 @@ void test_connect_force_port(void) if (CHECK_FAIL(cgroup_fd < 0)) return; - server_fd = start_server(AF_INET, SOCK_STREAM); + server_fd = start_server_with_port(AF_INET, SOCK_STREAM, 60123); if (CHECK_FAIL(server_fd < 0)) goto close_cgroup_fd; CHECK_FAIL(run_test(cgroup_fd, server_fd, AF_INET, SOCK_STREAM)); close(server_fd); - server_fd = start_server(AF_INET6, SOCK_STREAM); + server_fd = start_server_with_port(AF_INET6, SOCK_STREAM, 60124); if (CHECK_FAIL(server_fd < 0)) goto close_cgroup_fd; CHECK_FAIL(run_test(cgroup_fd, server_fd, AF_INET6, SOCK_STREAM)); close(server_fd); - server_fd = start_server(AF_INET, SOCK_DGRAM); + server_fd = start_server_with_port(AF_INET, SOCK_DGRAM, 60123); if (CHECK_FAIL(server_fd < 0)) goto close_cgroup_fd; CHECK_FAIL(run_test(cgroup_fd, server_fd, AF_INET, SOCK_DGRAM)); close(server_fd); - server_fd = start_server(AF_INET6, SOCK_DGRAM); + server_fd = start_server_with_port(AF_INET6, SOCK_DGRAM, 60124); if (CHECK_FAIL(server_fd < 0)) goto close_cgroup_fd; CHECK_FAIL(run_test(cgroup_fd, server_fd, AF_INET6, SOCK_DGRAM)); diff --git a/tools/testing/selftests/bpf/progs/connect_force_port4.c b/tools/testing/selftests/bpf/progs/connect_force_port4.c index 1b8eb34b2db0c..7396308677a30 100644 --- a/tools/testing/selftests/bpf/progs/connect_force_port4.c +++ b/tools/testing/selftests/bpf/progs/connect_force_port4.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #include +#include #include #include @@ -12,17 +13,71 @@ char _license[] SEC("license") = "GPL"; int _version SEC("version") = 1; +struct svc_addr { + __be32 addr; + __be16 port; +}; + +struct { + __uint(type, BPF_MAP_TYPE_SK_STORAGE); + __uint(map_flags, BPF_F_NO_PREALLOC); + __type(key, int); + __type(value, struct svc_addr); +} service_mapping SEC(".maps"); + SEC("cgroup/connect4") -int _connect4(struct bpf_sock_addr *ctx) +int connect4(struct bpf_sock_addr *ctx) { struct sockaddr_in sa = {}; + struct svc_addr *orig; + /* Force local address to 127.0.0.1:22222. */ sa.sin_family = AF_INET; sa.sin_port = bpf_htons(22222); - sa.sin_addr.s_addr = bpf_htonl(0x7f000001); /* 127.0.0.1 */ + sa.sin_addr.s_addr = bpf_htonl(0x7f000001); if (bpf_bind(ctx, (struct sockaddr *)&sa, sizeof(sa)) != 0) return 0; + /* Rewire service 1.2.3.4:60000 to backend 127.0.0.1:60123. */ + if (ctx->user_port == bpf_htons(60000)) { + orig = bpf_sk_storage_get(&service_mapping, ctx->sk, 0, + BPF_SK_STORAGE_GET_F_CREATE); + if (!orig) + return 0; + + orig->addr = ctx->user_ip4; + orig->port = ctx->user_port; + + ctx->user_ip4 = bpf_htonl(0x7f000001); + ctx->user_port = bpf_htons(60123); + } + return 1; +} + +SEC("cgroup/getsockname4") +int getsockname4(struct bpf_sock_addr *ctx) +{ + /* Expose local server as 1.2.3.4:60000 to client. */ + if (ctx->user_port == bpf_htons(60123)) { + ctx->user_ip4 = bpf_htonl(0x01020304); + ctx->user_port = bpf_htons(60000); + } + return 1; +} + +SEC("cgroup/getpeername4") +int getpeername4(struct bpf_sock_addr *ctx) +{ + struct svc_addr *orig; + + /* Expose service 1.2.3.4:60000 as peer instead of backend. */ + if (ctx->user_port == bpf_htons(60123)) { + orig = bpf_sk_storage_get(&service_mapping, ctx->sk, 0, 0); + if (orig) { + ctx->user_ip4 = orig->addr; + ctx->user_port = orig->port; + } + } return 1; } diff --git a/tools/testing/selftests/bpf/progs/connect_force_port6.c b/tools/testing/selftests/bpf/progs/connect_force_port6.c index ae6f7d750b4cf..c1a2b555e9ad1 100644 --- a/tools/testing/selftests/bpf/progs/connect_force_port6.c +++ b/tools/testing/selftests/bpf/progs/connect_force_port6.c @@ -12,17 +12,83 @@ char _license[] SEC("license") = "GPL"; int _version SEC("version") = 1; +struct svc_addr { + __be32 addr[4]; + __be16 port; +}; + +struct { + __uint(type, BPF_MAP_TYPE_SK_STORAGE); + __uint(map_flags, BPF_F_NO_PREALLOC); + __type(key, int); + __type(value, struct svc_addr); +} service_mapping SEC(".maps"); + SEC("cgroup/connect6") -int _connect6(struct bpf_sock_addr *ctx) +int connect6(struct bpf_sock_addr *ctx) { struct sockaddr_in6 sa = {}; + struct svc_addr *orig; + /* Force local address to [::1]:22223. */ sa.sin6_family = AF_INET6; sa.sin6_port = bpf_htons(22223); - sa.sin6_addr.s6_addr32[3] = bpf_htonl(1); /* ::1 */ + sa.sin6_addr.s6_addr32[3] = bpf_htonl(1); if (bpf_bind(ctx, (struct sockaddr *)&sa, sizeof(sa)) != 0) return 0; + /* Rewire service [fc00::1]:60000 to backend [::1]:60124. */ + if (ctx->user_port == bpf_htons(60000)) { + orig = bpf_sk_storage_get(&service_mapping, ctx->sk, 0, + BPF_SK_STORAGE_GET_F_CREATE); + if (!orig) + return 0; + + orig->addr[0] = ctx->user_ip6[0]; + orig->addr[1] = ctx->user_ip6[1]; + orig->addr[2] = ctx->user_ip6[2]; + orig->addr[3] = ctx->user_ip6[3]; + orig->port = ctx->user_port; + + ctx->user_ip6[0] = 0; + ctx->user_ip6[1] = 0; + ctx->user_ip6[2] = 0; + ctx->user_ip6[3] = bpf_htonl(1); + ctx->user_port = bpf_htons(60124); + } + return 1; +} + +SEC("cgroup/getsockname6") +int getsockname6(struct bpf_sock_addr *ctx) +{ + /* Expose local server as [fc00::1]:60000 to client. */ + if (ctx->user_port == bpf_htons(60124)) { + ctx->user_ip6[0] = bpf_htonl(0xfc000000); + ctx->user_ip6[1] = 0; + ctx->user_ip6[2] = 0; + ctx->user_ip6[3] = bpf_htonl(1); + ctx->user_port = bpf_htons(60000); + } + return 1; +} + +SEC("cgroup/getpeername6") +int getpeername6(struct bpf_sock_addr *ctx) +{ + struct svc_addr *orig; + + /* Expose service [fc00::1]:60000 as peer instead of backend. */ + if (ctx->user_port == bpf_htons(60124)) { + orig = bpf_sk_storage_get(&service_mapping, ctx->sk, 0, 0); + if (orig) { + ctx->user_ip6[0] = orig->addr[0]; + ctx->user_ip6[1] = orig->addr[1]; + ctx->user_ip6[2] = orig->addr[2]; + ctx->user_ip6[3] = orig->addr[3]; + ctx->user_port = orig->port; + } + } return 1; }