From 78b1b27db91c7a94297a8b6a665fe7e86dfc5750 Mon Sep 17 00:00:00 2001 From: Dmitry Safonov <0x7f454c46@gmail.com> Date: Fri, 7 Jun 2024 00:25:59 +0100 Subject: [PATCH] net/tcp: Remove tcp_hash_fail() Now there are tracepoints, that cover all functionality of tcp_hash_fail(), but also wire up missing places They are also faster, can be disabled and provide filtering. This potentially may create a regression if a userspace depends on dmesg logs. Fingers crossed, let's see if anyone complains in reality. Reviewed-by: Eric Dumazet Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Signed-off-by: David S. Miller --- include/net/tcp_ao.h | 37 ------------------------------------- net/ipv4/tcp.c | 25 ------------------------- net/ipv4/tcp_ao.c | 9 --------- 3 files changed, 71 deletions(-) diff --git a/include/net/tcp_ao.h b/include/net/tcp_ao.h index 198e02004ad2..1d46460d0fef 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -149,43 +149,6 @@ extern struct static_key_false_deferred tcp_ao_needed; #define static_branch_tcp_ao() false #endif -static inline bool tcp_hash_should_produce_warnings(void) -{ - return static_branch_tcp_md5() || static_branch_tcp_ao(); -} - -#define tcp_hash_fail(msg, family, skb, fmt, ...) \ -do { \ - const struct tcphdr *th = tcp_hdr(skb); \ - char hdr_flags[6]; \ - char *f = hdr_flags; \ - \ - if (!tcp_hash_should_produce_warnings()) \ - break; \ - if (th->fin) \ - *f++ = 'F'; \ - if (th->syn) \ - *f++ = 'S'; \ - if (th->rst) \ - *f++ = 'R'; \ - if (th->psh) \ - *f++ = 'P'; \ - if (th->ack) \ - *f++ = '.'; \ - *f = 0; \ - if ((family) == AF_INET) { \ - net_info_ratelimited("%s for %pI4.%d->%pI4.%d [%s] " fmt "\n", \ - msg, &ip_hdr(skb)->saddr, ntohs(th->source), \ - &ip_hdr(skb)->daddr, ntohs(th->dest), \ - hdr_flags, ##__VA_ARGS__); \ - } else { \ - net_info_ratelimited("%s for [%pI6c].%d->[%pI6c].%d [%s]" fmt "\n", \ - msg, &ipv6_hdr(skb)->saddr, ntohs(th->source), \ - &ipv6_hdr(skb)->daddr, ntohs(th->dest), \ - hdr_flags, ##__VA_ARGS__); \ - } \ -} while (0) - #ifdef CONFIG_TCP_AO /* TCP-AO structures and functions */ struct tcp4_ao_context { diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 73152ce1367e..e03a342c9162 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4484,7 +4484,6 @@ tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, if (!key && hash_location) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); - tcp_hash_fail("Unexpected MD5 Hash found", family, skb, ""); trace_tcp_hash_md5_unexpected(sk, skb); return SKB_DROP_REASON_TCP_MD5UNEXPECTED; } @@ -4500,21 +4499,6 @@ tcp_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, NULL, skb); if (genhash || memcmp(hash_location, newhash, 16) != 0) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE); - if (family == AF_INET) { - tcp_hash_fail("MD5 Hash failed", AF_INET, skb, "%s L3 index %d", - genhash ? "tcp_v4_calc_md5_hash failed" - : "", l3index); - } else { - if (genhash) { - tcp_hash_fail("MD5 Hash failed", - AF_INET6, skb, "L3 index %d", - l3index); - } else { - tcp_hash_fail("MD5 Hash mismatch", - AF_INET6, skb, "L3 index %d", - l3index); - } - } trace_tcp_hash_md5_mismatch(sk, skb); return SKB_DROP_REASON_TCP_MD5FAILURE; } @@ -4545,8 +4529,6 @@ tcp_inbound_hash(struct sock *sk, const struct request_sock *req, /* Invalid option or two times meet any of auth options */ if (tcp_parse_auth_options(th, &md5_location, &aoh)) { - tcp_hash_fail("TCP segment has incorrect auth options set", - family, skb, ""); trace_tcp_hash_bad_header(sk, skb); return SKB_DROP_REASON_TCP_AUTH_HDR; } @@ -4564,9 +4546,6 @@ tcp_inbound_hash(struct sock *sk, const struct request_sock *req, } NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOBAD); - tcp_hash_fail("TCP connection can't start/end using TCP-AO", - family, skb, "%s", - !aoh ? "missing AO" : "AO signed"); trace_tcp_ao_handshake_failure(sk, skb, keyid, rnext, maclen); return SKB_DROP_REASON_TCP_AOFAILURE; } @@ -4585,15 +4564,11 @@ tcp_inbound_hash(struct sock *sk, const struct request_sock *req, * always at least one current_key. */ if (tcp_ao_required(sk, saddr, family, l3index, true)) { - tcp_hash_fail("AO hash is required, but not found", - family, skb, "L3 index %d", l3index); trace_tcp_hash_ao_required(sk, skb); return SKB_DROP_REASON_TCP_AONOTFOUND; } if (unlikely(tcp_md5_do_lookup(sk, l3index, saddr, family))) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); - tcp_hash_fail("MD5 Hash not found", - family, skb, "L3 index %d", l3index); trace_tcp_hash_md5_required(sk, skb); return SKB_DROP_REASON_TCP_MD5NOTFOUND; } diff --git a/net/ipv4/tcp_ao.c b/net/ipv4/tcp_ao.c index 1e5087c6cd7d..0de863aa5f66 100644 --- a/net/ipv4/tcp_ao.c +++ b/net/ipv4/tcp_ao.c @@ -893,9 +893,6 @@ tcp_ao_verify_hash(const struct sock *sk, const struct sk_buff *skb, NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOBAD); atomic64_inc(&info->counters.pkt_bad); atomic64_inc(&key->pkt_bad); - tcp_hash_fail("AO hash wrong length", family, skb, - "%u != %d L3index: %d", maclen, - tcp_ao_maclen(key), l3index); trace_tcp_ao_wrong_maclen(sk, skb, aoh->keyid, aoh->rnext_keyid, maclen); return SKB_DROP_REASON_TCP_AOFAILURE; @@ -912,8 +909,6 @@ tcp_ao_verify_hash(const struct sock *sk, const struct sk_buff *skb, NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOBAD); atomic64_inc(&info->counters.pkt_bad); atomic64_inc(&key->pkt_bad); - tcp_hash_fail("AO hash mismatch", family, skb, - "L3index: %d", l3index); trace_tcp_ao_mismatch(sk, skb, aoh->keyid, aoh->rnext_keyid, maclen); kfree(hash_buf); @@ -945,8 +940,6 @@ tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb, info = rcu_dereference(tcp_sk(sk)->ao_info); if (!info) { NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOKEYNOTFOUND); - tcp_hash_fail("AO key not found", family, skb, - "keyid: %u L3index: %d", aoh->keyid, l3index); trace_tcp_ao_key_not_found(sk, skb, aoh->keyid, aoh->rnext_keyid, maclen); return SKB_DROP_REASON_TCP_AOUNEXPECTED; @@ -1057,8 +1050,6 @@ verify_hash: key_not_found: NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOKEYNOTFOUND); atomic64_inc(&info->counters.key_not_found); - tcp_hash_fail("Requested by the peer AO key id not found", - family, skb, "L3index: %d", l3index); trace_tcp_ao_key_not_found(sk, skb, aoh->keyid, aoh->rnext_keyid, maclen); return SKB_DROP_REASON_TCP_AOKEYNOTFOUND;