| Message ID | 20240224-tcp-ao-tracepoints-v1-3-15f31b7f30a7@arista.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | net/tcp: TCP-AO and TCP-MD5 tracepoints | expand |
On Sat, Feb 24, 2024 at 10:04 AM Dmitry Safonov <dima@arista.com> wrote: > > Two reasons: > 1. It's grown up enough > 2. In order to not do header spaghetti by including > <trace/events/tcp.h>, which is necessary for TCP tracepoints. > > Signed-off-by: Dmitry Safonov <dima@arista.com> Okay, but what about CONFIG_IPV6=m ? I do not see any EXPORT_SYMBOL() in this patch.
On 2/24/24 09:30, Eric Dumazet wrote: > On Sat, Feb 24, 2024 at 10:04 AM Dmitry Safonov <dima@arista.com> wrote: >> >> Two reasons: >> 1. It's grown up enough >> 2. In order to not do header spaghetti by including >> <trace/events/tcp.h>, which is necessary for TCP tracepoints. >> >> Signed-off-by: Dmitry Safonov <dima@arista.com> > > Okay, but what about CONFIG_IPV6=m ? > > I do not see any EXPORT_SYMBOL() in this patch. Ouch. I keep forgetting about that case, will fix in v2. Thanks, Dmitry
On Sat, Feb 24, 2024 at 09:04:11AM +0000, Dmitry Safonov wrote: > Two reasons: > 1. It's grown up enough > 2. In order to not do header spaghetti by including > <trace/events/tcp.h>, which is necessary for TCP tracepoints. > > Signed-off-by: Dmitry Safonov <dima@arista.com> ... > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > index c82dc42f57c6..5fd61ae6bcc9 100644 > --- a/net/ipv4/tcp.c > +++ b/net/ipv4/tcp.c > @@ -4485,6 +4485,78 @@ EXPORT_SYMBOL(tcp_inbound_md5_hash); > > #endif > > +/* Called with rcu_read_lock() */ > +enum skb_drop_reason > +tcp_inbound_hash(struct sock *sk, const struct request_sock *req, > + const struct sk_buff *skb, > + const void *saddr, const void *daddr, > + int family, int dif, int sdif) > +{ > + const struct tcphdr *th = tcp_hdr(skb); > + const struct tcp_ao_hdr *aoh; > + const __u8 *md5_location; > + int l3index; > + > + /* 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, ""); > + return SKB_DROP_REASON_TCP_AUTH_HDR; > + } > + > + if (req) { > + if (tcp_rsk_used_ao(req) != !!aoh) { > + u8 keyid, rnext, maclen; > + > + if (aoh) { > + keyid = aoh->keyid; > + rnext = aoh->rnext_keyid; > + maclen = tcp_ao_hdr_maclen(aoh); > + } else { > + keyid = rnext = maclen = 0; > + } Hi Dmitry, it looks like keyid is set but otherwise unused. Flagged by W=1 builds with gcc-13 and clang-17. > + > + 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"); > + return SKB_DROP_REASON_TCP_AOFAILURE; > + } > + } > + > + /* sdif set, means packet ingressed via a device > + * in an L3 domain and dif is set to the l3mdev > + */ > + l3index = sdif ? dif : 0; > + > + /* Fast path: unsigned segments */ > + if (likely(!md5_location && !aoh)) { > + /* Drop if there's TCP-MD5 or TCP-AO key with any rcvid/sndid > + * for the remote peer. On TCP-AO established connection > + * the last key is impossible to remove, so there's > + * 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); > + 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); > + return SKB_DROP_REASON_TCP_MD5NOTFOUND; > + } > + return SKB_NOT_DROPPED_YET; > + } > + > + if (aoh) > + return tcp_inbound_ao_hash(sk, skb, family, req, l3index, aoh); > + > + return tcp_inbound_md5_hash(sk, skb, saddr, daddr, family, > + l3index, md5_location); > +} > + > void tcp_done(struct sock *sk) > { > struct request_sock *req; > > -- > 2.43.0 > >
On Mon, Feb 26, 2024 at 8:43 PM Simon Horman <horms@kernel.org> wrote: > > On Sat, Feb 24, 2024 at 09:04:11AM +0000, Dmitry Safonov wrote: [..] > > + if (req) { > > + if (tcp_rsk_used_ao(req) != !!aoh) { > > + u8 keyid, rnext, maclen; > > + > > + if (aoh) { > > + keyid = aoh->keyid; > > + rnext = aoh->rnext_keyid; > > + maclen = tcp_ao_hdr_maclen(aoh); > > + } else { > > + keyid = rnext = maclen = 0; > > + } > > Hi Dmitry, > > it looks like keyid is set but otherwise unused. > > Flagged by W=1 builds with gcc-13 and clang-17. Hi Simon, Yeah, I think I didn't notice it when I was splitting the WIP patch. It should be in the very next patch that uses them: + trace_tcp_ao_handshake_failure(sk, skb, keyid, rnext, maclen); Thanks for the report, going to fix in v2, Dmitry
diff --git a/include/net/tcp.h b/include/net/tcp.h index c1fff9207e2d..c80bdfb5efe5 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2789,66 +2789,9 @@ static inline bool tcp_ao_required(struct sock *sk, const void *saddr, return false; } -/* Called with rcu_read_lock() */ -static inline enum skb_drop_reason -tcp_inbound_hash(struct sock *sk, const struct request_sock *req, - const struct sk_buff *skb, - const void *saddr, const void *daddr, - int family, int dif, int sdif) -{ - const struct tcphdr *th = tcp_hdr(skb); - const struct tcp_ao_hdr *aoh; - const __u8 *md5_location; - int l3index; - - /* 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, ""); - return SKB_DROP_REASON_TCP_AUTH_HDR; - } - - if (req) { - if (tcp_rsk_used_ao(req) != !!aoh) { - 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"); - return SKB_DROP_REASON_TCP_AOFAILURE; - } - } - - /* sdif set, means packet ingressed via a device - * in an L3 domain and dif is set to the l3mdev - */ - l3index = sdif ? dif : 0; - - /* Fast path: unsigned segments */ - if (likely(!md5_location && !aoh)) { - /* Drop if there's TCP-MD5 or TCP-AO key with any rcvid/sndid - * for the remote peer. On TCP-AO established connection - * the last key is impossible to remove, so there's - * 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); - 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); - return SKB_DROP_REASON_TCP_MD5NOTFOUND; - } - return SKB_NOT_DROPPED_YET; - } - - if (aoh) - return tcp_inbound_ao_hash(sk, skb, family, req, l3index, aoh); - - return tcp_inbound_md5_hash(sk, skb, saddr, daddr, family, - l3index, md5_location); -} +enum skb_drop_reason tcp_inbound_hash(struct sock *sk, + const struct request_sock *req, const struct sk_buff *skb, + const void *saddr, const void *daddr, + int family, int dif, int sdif); #endif /* _TCP_H */ diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index c82dc42f57c6..5fd61ae6bcc9 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4485,6 +4485,78 @@ EXPORT_SYMBOL(tcp_inbound_md5_hash); #endif +/* Called with rcu_read_lock() */ +enum skb_drop_reason +tcp_inbound_hash(struct sock *sk, const struct request_sock *req, + const struct sk_buff *skb, + const void *saddr, const void *daddr, + int family, int dif, int sdif) +{ + const struct tcphdr *th = tcp_hdr(skb); + const struct tcp_ao_hdr *aoh; + const __u8 *md5_location; + int l3index; + + /* 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, ""); + return SKB_DROP_REASON_TCP_AUTH_HDR; + } + + if (req) { + if (tcp_rsk_used_ao(req) != !!aoh) { + u8 keyid, rnext, maclen; + + if (aoh) { + keyid = aoh->keyid; + rnext = aoh->rnext_keyid; + maclen = tcp_ao_hdr_maclen(aoh); + } else { + keyid = rnext = maclen = 0; + } + + 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"); + return SKB_DROP_REASON_TCP_AOFAILURE; + } + } + + /* sdif set, means packet ingressed via a device + * in an L3 domain and dif is set to the l3mdev + */ + l3index = sdif ? dif : 0; + + /* Fast path: unsigned segments */ + if (likely(!md5_location && !aoh)) { + /* Drop if there's TCP-MD5 or TCP-AO key with any rcvid/sndid + * for the remote peer. On TCP-AO established connection + * the last key is impossible to remove, so there's + * 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); + 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); + return SKB_DROP_REASON_TCP_MD5NOTFOUND; + } + return SKB_NOT_DROPPED_YET; + } + + if (aoh) + return tcp_inbound_ao_hash(sk, skb, family, req, l3index, aoh); + + return tcp_inbound_md5_hash(sk, skb, saddr, daddr, family, + l3index, md5_location); +} + void tcp_done(struct sock *sk) { struct request_sock *req;
Two reasons: 1. It's grown up enough 2. In order to not do header spaghetti by including <trace/events/tcp.h>, which is necessary for TCP tracepoints. Signed-off-by: Dmitry Safonov <dima@arista.com> --- include/net/tcp.h | 65 ++++--------------------------------------------- net/ipv4/tcp.c | 72 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 76 insertions(+), 61 deletions(-)