From f7dca36fc54afa2eb76bff8d0589a2ef18caea91 Mon Sep 17 00:00:00 2001 From: Dmitry Safonov Date: Mon, 23 Oct 2023 20:21:59 +0100 Subject: net/tcp: Add tcp_parse_auth_options() Introduce a helper that: (1) shares the common code with TCP-MD5 header options parsing (2) looks for hash signature only once for both TCP-MD5 and TCP-AO (3) fails with -EEXIST if any TCP sign option is present twice, see RFC5925 (2.2): ">> A single TCP segment MUST NOT have more than one TCP-AO in its options sequence. When multiple TCP-AOs appear, TCP MUST discard the segment." Co-developed-by: Francesco Ruggeri Signed-off-by: Francesco Ruggeri Co-developed-by: Salam Noureddine Signed-off-by: Salam Noureddine Signed-off-by: Dmitry Safonov Acked-by: David Ahern Signed-off-by: David S. Miller --- include/net/tcp.h | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) (limited to 'include/net/tcp.h') diff --git a/include/net/tcp.h b/include/net/tcp.h index 96e83159f1be..423807ae3e37 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -438,7 +438,6 @@ int tcp_mmap(struct file *file, struct socket *sock, void tcp_parse_options(const struct net *net, const struct sk_buff *skb, struct tcp_options_received *opt_rx, int estab, struct tcp_fastopen_cookie *foc); -const u8 *tcp_parse_md5sig_option(const struct tcphdr *th); /* * BPF SKB-less helpers @@ -2675,6 +2674,29 @@ static inline u64 tcp_transmit_time(const struct sock *sk) return 0; } +static inline int tcp_parse_auth_options(const struct tcphdr *th, + const u8 **md5_hash, const struct tcp_ao_hdr **aoh) +{ + const u8 *md5_tmp, *ao_tmp; + int ret; + + ret = tcp_do_parse_auth_options(th, &md5_tmp, &ao_tmp); + if (ret) + return ret; + + if (md5_hash) + *md5_hash = md5_tmp; + + if (aoh) { + if (!ao_tmp) + *aoh = NULL; + else + *aoh = (struct tcp_ao_hdr *)(ao_tmp - 2); + } + + return 0; +} + static inline bool tcp_ao_required(struct sock *sk, const void *saddr, int family) { -- cgit v1.2.3