| Message ID | 56e95bcb5c99a4547cb896b1e7e732d7926d23e1.1541695683.git.rdna@fb.com |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | bpf: Support socket lookup in CGROUP_SOCK_ADDR progs | expand |
On Thu, Nov 08, 2018 at 08:54:24AM -0800, Andrey Ignatov wrote: > Make bpf_sk_lookup_tcp, bpf_sk_lookup_udp and bpf_sk_release helpers > available in programs of type BPF_PROG_TYPE_CGROUP_SOCK_ADDR. > > Such programs operate on sockets and have access to socket and struct > sockaddr passed by user to system calls such as sys_bind, sys_connect, > sys_sendmsg. > > It's useful to be able to lookup other sockets from these programs. > E.g. sys_connect may lookup IP:port endpoint and if there is a server > socket bound to that endpoint ("server" can be defined by saddr & sport > being zero), redirect client connection to it by rewriting IP:port in > sockaddr passed to sys_connect. > > Signed-off-by: Andrey Ignatov <rdna@fb.com> > Acked-by: Alexei Starovoitov <ast@kernel.org> > --- > net/core/filter.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 53 insertions(+) > > diff --git a/net/core/filter.c b/net/core/filter.c > index dc0f86a707b7..2e8575a34a1e 100644 > --- a/net/core/filter.c > +++ b/net/core/filter.c > @@ -4971,6 +4971,51 @@ static const struct bpf_func_proto bpf_sk_release_proto = { > .ret_type = RET_INTEGER, > .arg1_type = ARG_PTR_TO_SOCKET, > }; > + > +static unsigned long > +bpf_sock_addr_sk_lookup(struct sock *sk, struct bpf_sock_tuple *tuple, u32 len, > + u8 proto, u64 netns_id, u64 flags) Nit. This func looks unnecessary. as good as directly calling __bpf_sk_lookup(). Others LGTM. > +{ > + return __bpf_sk_lookup(NULL, tuple, len, proto, netns_id, sock_net(sk), > + 0, flags); > +} > + > +BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp, struct bpf_sock_addr_kern *, ctx, > + struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags) > +{ > + return bpf_sock_addr_sk_lookup(ctx->sk, tuple, len, IPPROTO_TCP, > + netns_id, flags); > +} > + > +static const struct bpf_func_proto bpf_sock_addr_sk_lookup_tcp_proto = { > + .func = bpf_sock_addr_sk_lookup_tcp, > + .gpl_only = false, > + .ret_type = RET_PTR_TO_SOCKET_OR_NULL, > + .arg1_type = ARG_PTR_TO_CTX, > + .arg2_type = ARG_PTR_TO_MEM, > + .arg3_type = ARG_CONST_SIZE, > + .arg4_type = ARG_ANYTHING, > + .arg5_type = ARG_ANYTHING, > +}; > + > +BPF_CALL_5(bpf_sock_addr_sk_lookup_udp, struct bpf_sock_addr_kern *, ctx, > + struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags) > +{ > + return bpf_sock_addr_sk_lookup(ctx->sk, tuple, len, IPPROTO_UDP, > + netns_id, flags); > +} > + > +static const struct bpf_func_proto bpf_sock_addr_sk_lookup_udp_proto = { > + .func = bpf_sock_addr_sk_lookup_udp, > + .gpl_only = false, > + .ret_type = RET_PTR_TO_SOCKET_OR_NULL, > + .arg1_type = ARG_PTR_TO_CTX, > + .arg2_type = ARG_PTR_TO_MEM, > + .arg3_type = ARG_CONST_SIZE, > + .arg4_type = ARG_ANYTHING, > + .arg5_type = ARG_ANYTHING, > +}; > + > #endif /* CONFIG_INET */ > > bool bpf_helper_changes_pkt_data(void *func) > @@ -5077,6 +5122,14 @@ sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) > return &bpf_get_socket_cookie_sock_addr_proto; > case BPF_FUNC_get_local_storage: > return &bpf_get_local_storage_proto; > +#ifdef CONFIG_INET > + case BPF_FUNC_sk_lookup_tcp: > + return &bpf_sock_addr_sk_lookup_tcp_proto; > + case BPF_FUNC_sk_lookup_udp: > + return &bpf_sock_addr_sk_lookup_udp_proto; > + case BPF_FUNC_sk_release: > + return &bpf_sk_release_proto; > +#endif /* CONFIG_INET */ > default: > return bpf_base_func_proto(func_id); > } > -- > 2.17.1 >
diff --git a/net/core/filter.c b/net/core/filter.c index dc0f86a707b7..2e8575a34a1e 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -4971,6 +4971,51 @@ static const struct bpf_func_proto bpf_sk_release_proto = { .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_SOCKET, }; + +static unsigned long +bpf_sock_addr_sk_lookup(struct sock *sk, struct bpf_sock_tuple *tuple, u32 len, + u8 proto, u64 netns_id, u64 flags) +{ + return __bpf_sk_lookup(NULL, tuple, len, proto, netns_id, sock_net(sk), + 0, flags); +} + +BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp, struct bpf_sock_addr_kern *, ctx, + struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags) +{ + return bpf_sock_addr_sk_lookup(ctx->sk, tuple, len, IPPROTO_TCP, + netns_id, flags); +} + +static const struct bpf_func_proto bpf_sock_addr_sk_lookup_tcp_proto = { + .func = bpf_sock_addr_sk_lookup_tcp, + .gpl_only = false, + .ret_type = RET_PTR_TO_SOCKET_OR_NULL, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_PTR_TO_MEM, + .arg3_type = ARG_CONST_SIZE, + .arg4_type = ARG_ANYTHING, + .arg5_type = ARG_ANYTHING, +}; + +BPF_CALL_5(bpf_sock_addr_sk_lookup_udp, struct bpf_sock_addr_kern *, ctx, + struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags) +{ + return bpf_sock_addr_sk_lookup(ctx->sk, tuple, len, IPPROTO_UDP, + netns_id, flags); +} + +static const struct bpf_func_proto bpf_sock_addr_sk_lookup_udp_proto = { + .func = bpf_sock_addr_sk_lookup_udp, + .gpl_only = false, + .ret_type = RET_PTR_TO_SOCKET_OR_NULL, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_PTR_TO_MEM, + .arg3_type = ARG_CONST_SIZE, + .arg4_type = ARG_ANYTHING, + .arg5_type = ARG_ANYTHING, +}; + #endif /* CONFIG_INET */ bool bpf_helper_changes_pkt_data(void *func) @@ -5077,6 +5122,14 @@ sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_socket_cookie_sock_addr_proto; case BPF_FUNC_get_local_storage: return &bpf_get_local_storage_proto; +#ifdef CONFIG_INET + case BPF_FUNC_sk_lookup_tcp: + return &bpf_sock_addr_sk_lookup_tcp_proto; + case BPF_FUNC_sk_lookup_udp: + return &bpf_sock_addr_sk_lookup_udp_proto; + case BPF_FUNC_sk_release: + return &bpf_sk_release_proto; +#endif /* CONFIG_INET */ default: return bpf_base_func_proto(func_id); }
Make bpf_sk_lookup_tcp, bpf_sk_lookup_udp and bpf_sk_release helpers available in programs of type BPF_PROG_TYPE_CGROUP_SOCK_ADDR. Such programs operate on sockets and have access to socket and struct sockaddr passed by user to system calls such as sys_bind, sys_connect, sys_sendmsg. It's useful to be able to lookup other sockets from these programs. E.g. sys_connect may lookup IP:port endpoint and if there is a server socket bound to that endpoint ("server" can be defined by saddr & sport being zero), redirect client connection to it by rewriting IP:port in sockaddr passed to sys_connect. Signed-off-by: Andrey Ignatov <rdna@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> --- net/core/filter.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+)