diff options
| -rw-r--r-- | include/linux/filter.h | 1 | ||||
| -rw-r--r-- | include/net/tcp.h | 6 | ||||
| -rw-r--r-- | include/uapi/linux/bpf.h | 6 | ||||
| -rw-r--r-- | net/core/filter.c | 36 |
4 files changed, 47 insertions, 2 deletions
diff --git a/include/linux/filter.h b/include/linux/filter.h index 80b5b482cb46..0062302e1285 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -985,6 +985,7 @@ struct bpf_sock_ops_kern { u32 reply; u32 replylong[4]; }; + u32 is_fullsock; }; #endif /* __LINUX_FILTER_H__ */ diff --git a/include/net/tcp.h b/include/net/tcp.h index 4e09398009c1..89a656077884 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2012,10 +2012,12 @@ static inline int tcp_call_bpf(struct sock *sk, int op) struct bpf_sock_ops_kern sock_ops; int ret; - if (sk_fullsock(sk)) + memset(&sock_ops, 0, sizeof(sock_ops)); + if (sk_fullsock(sk)) { + sock_ops.is_fullsock = 1; sock_owned_by_me(sk); + } - memset(&sock_ops, 0, sizeof(sock_ops)); sock_ops.sk = sk; sock_ops.op = op; diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 4c223ab30293..80d62e88590c 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -941,6 +941,12 @@ struct bpf_sock_ops { __u32 local_ip6[4]; /* Stored in network byte order */ __u32 remote_port; /* Stored in network byte order */ __u32 local_port; /* stored in host byte order */ + __u32 is_fullsock; /* Some TCP fields are only valid if + * there is a full socket. If not, the + * fields read as zero. + */ + __u32 snd_cwnd; + __u32 srtt_us; /* Averaged RTT << 3 in usecs */ }; /* List of known BPF sock_ops operators. diff --git a/net/core/filter.c b/net/core/filter.c index 4d644ad17457..754abe1041b7 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -4437,6 +4437,42 @@ static u32 sock_ops_convert_ctx_access(enum bpf_access_type type, *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; + +/* Helper macro for adding read access to tcp_sock fields. */ +#define SOCK_OPS_GET_TCP32(FIELD_NAME) \ + do { \ + BUILD_BUG_ON(FIELD_SIZEOF(struct tcp_sock, FIELD_NAME) != 4); \ + *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_W, si->dst_reg, si->dst_reg, \ + offsetof(struct tcp_sock, FIELD_NAME)); \ + } while (0) + + case offsetof(struct bpf_sock_ops, snd_cwnd): + SOCK_OPS_GET_TCP32(snd_cwnd); + break; + + case offsetof(struct bpf_sock_ops, srtt_us): + SOCK_OPS_GET_TCP32(srtt_us); + break; } return insn - insn_buf; } |