From: Dmitry Safonov <0x7f454...@gmail.com>

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 <eduma...@google.com>
Signed-off-by: Dmitry Safonov <0x7f454...@gmail.com>
---
 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 @@ tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff 
*skb,
 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;

-- 
2.42.0



Reply via email to