From 6f9bd3d731aac0d2ac21dd78a642af5df38fb5c5 Mon Sep 17 00:00:00 2001 From: Lawrence Brakmo Date: Thu, 25 Jan 2018 16:14:13 -0800 Subject: [PATCH] bpf: Add sock_ops R/W access to tclass Adds direct write access to sk_txhash and access to tclass for ipv6 flows through getsockopt and setsockopt. Sample usage for tclass: bpf_getsockopt(skops, SOL_IPV6, IPV6_TCLASS, &v, sizeof(v)) where skops is a pointer to the ctx (struct bpf_sock_ops). Signed-off-by: Lawrence Brakmo Signed-off-by: Alexei Starovoitov --- net/core/filter.c | 47 +++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 45 insertions(+), 2 deletions(-) diff --git a/net/core/filter.c b/net/core/filter.c index a858ebc4ece4..fe2c7937351f 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; } @@ -3871,6 +3911,7 @@ static bool sock_ops_is_valid_access(int off, int size, if (type == BPF_WRITE) { switch (off) { case offsetof(struct bpf_sock_ops, reply): + case offsetof(struct bpf_sock_ops, sk_txhash): if (size != size_default) return false; break; @@ -4690,7 +4731,8 @@ static u32 sock_ops_convert_ctx_access(enum bpf_access_type type, break; case offsetof(struct bpf_sock_ops, sk_txhash): - SOCK_OPS_GET_FIELD(sk_txhash, sk_txhash, struct sock); + SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash, + struct sock, type); break; case offsetof(struct bpf_sock_ops, bytes_received): @@ -4701,6 +4743,7 @@ static u32 sock_ops_convert_ctx_access(enum bpf_access_type type, case offsetof(struct bpf_sock_ops, bytes_acked): SOCK_OPS_GET_FIELD(bytes_acked, bytes_acked, struct tcp_sock); break; + } return insn - insn_buf; } -- 2.30.2