From 1314ef561102e534e14cb1d37f89f5c1df0b2ea7 Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Wed, 12 Jun 2019 10:30:38 -0700 Subject: [PATCH] bpf: export bpf_sock for BPF_PROG_TYPE_SOCK_OPS prog type And let it use bpf_sk_storage_{get,delete} helpers to access socket storage. Kernel context (struct bpf_sock_ops_kern) already has sk member, so I just expose it to the BPF hooks. I use PTR_TO_SOCKET_OR_NULL and return NULL in !is_fullsock case. I also export bpf_tcp_sock to make it possible to access tcp socket stats. Cc: Martin Lau Signed-off-by: Stanislav Fomichev Signed-off-by: Daniel Borkmann --- include/uapi/linux/bpf.h | 1 + net/core/filter.c | 26 ++++++++++++++++++++++++++ 2 files changed, 27 insertions(+) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 8815fc418cde..d0a23476f887 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -3299,6 +3299,7 @@ struct bpf_sock_ops { __u32 sk_txhash; __u64 bytes_received; __u64 bytes_acked; + __bpf_md_ptr(struct bpf_sock *, sk); }; /* Definitions for bpf_sock_ops_cb_flags */ diff --git a/net/core/filter.c b/net/core/filter.c index 37c4a2fd559b..8c18f2781afa 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -6147,6 +6147,14 @@ sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_local_storage_proto; case BPF_FUNC_perf_event_output: return &bpf_sockopt_event_output_proto; + case BPF_FUNC_sk_storage_get: + return &bpf_sk_storage_get_proto; + case BPF_FUNC_sk_storage_delete: + return &bpf_sk_storage_delete_proto; +#ifdef CONFIG_INET + case BPF_FUNC_tcp_sock: + return &bpf_tcp_sock_proto; +#endif /* CONFIG_INET */ default: return bpf_base_func_proto(func_id); } @@ -6882,6 +6890,11 @@ static bool sock_ops_is_valid_access(int off, int size, if (size != sizeof(__u64)) return false; break; + case offsetof(struct bpf_sock_ops, sk): + if (size != sizeof(__u64)) + return false; + info->reg_type = PTR_TO_SOCKET_OR_NULL; + break; default: if (size != size_default) return false; @@ -8053,6 +8066,19 @@ static u32 sock_ops_convert_ctx_access(enum bpf_access_type type, SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash, struct sock, type); break; + case offsetof(struct bpf_sock_ops, sk): + *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, 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)); + break; } return insn - insn_buf; } -- 2.30.2