From 7d5d5525bd88313e6fd90c0659665aee5114bc2d Mon Sep 17 00:00:00 2001 From: YOSHIFUJI Hideaki Date: Thu, 17 Apr 2008 12:29:53 +0900 Subject: [PATCH] tcp md5sig: Share MD5 Signature option parser between IPv4 and IPv6. Signed-off-by: YOSHIFUJI Hideaki --- include/net/tcp.h | 2 ++ net/ipv4/tcp_input.c | 40 ++++++++++++++++++++++++++++++++++++++++ net/ipv4/tcp_ipv4.c | 42 +----------------------------------------- net/ipv6/tcp_ipv6.c | 33 +-------------------------------- 4 files changed, 44 insertions(+), 73 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index 633147cb6bbc..b1c4b78f1cb8 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -399,6 +399,8 @@ extern void tcp_parse_options(struct sk_buff *skb, struct tcp_options_received *opt_rx, int estab); +extern u8 *tcp_parse_md5sig_option(struct tcphdr *th); + /* * TCP v4 functions exported for the inet6 API */ diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index eba873e9b560..f331e67f2328 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3450,6 +3450,43 @@ static int tcp_fast_parse_options(struct sk_buff *skb, struct tcphdr *th, return 1; } +#ifdef CONFIG_TCP_MD5SIG +/* + * Parse MD5 Signature option + */ +u8 *tcp_parse_md5sig_option(struct tcphdr *th) +{ + int length = (th->doff << 2) - sizeof (*th); + u8 *ptr = (u8*)(th + 1); + + /* If the TCP option is too short, we can short cut */ + if (length < TCPOLEN_MD5SIG) + return NULL; + + while (length > 0) { + int opcode = *ptr++; + int opsize; + + switch(opcode) { + case TCPOPT_EOL: + return NULL; + case TCPOPT_NOP: + length--; + continue; + default: + opsize = *ptr++; + if (opsize < 2 || opsize > length) + return NULL; + if (opcode == TCPOPT_MD5SIG) + return ptr; + } + ptr += opsize - 2; + length -= opsize; + } + return NULL; +} +#endif + static inline void tcp_store_ts_recent(struct tcp_sock *tp) { tp->rx_opt.ts_recent = tp->rx_opt.rcv_tsval; @@ -5467,6 +5504,9 @@ EXPORT_SYMBOL(sysctl_tcp_ecn); EXPORT_SYMBOL(sysctl_tcp_reordering); EXPORT_SYMBOL(sysctl_tcp_adv_win_scale); EXPORT_SYMBOL(tcp_parse_options); +#ifdef CONFIG_TCP_MD5SIG +EXPORT_SYMBOL(tcp_parse_md5sig_option); +#endif EXPORT_SYMBOL(tcp_rcv_established); EXPORT_SYMBOL(tcp_rcv_state_process); EXPORT_SYMBOL(tcp_initialize_rcv_mss); diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index cd601a866c2f..56f550933644 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1134,52 +1134,12 @@ static int tcp_v4_inbound_md5_hash(struct sock *sk, struct sk_buff *skb) struct tcp_md5sig_key *hash_expected; const struct iphdr *iph = ip_hdr(skb); struct tcphdr *th = tcp_hdr(skb); - int length = (th->doff << 2) - sizeof(struct tcphdr); int genhash; - unsigned char *ptr; unsigned char newhash[16]; hash_expected = tcp_v4_md5_do_lookup(sk, iph->saddr); + hash_location = tcp_parse_md5sig_option(th); - /* - * If the TCP option length is less than the TCP_MD5SIG - * option length, then we can shortcut - */ - if (length < TCPOLEN_MD5SIG) { - if (hash_expected) - return 1; - else - return 0; - } - - /* Okay, we can't shortcut - we have to grub through the options */ - ptr = (unsigned char *)(th + 1); - while (length > 0) { - int opcode = *ptr++; - int opsize; - - switch (opcode) { - case TCPOPT_EOL: - goto done_opts; - case TCPOPT_NOP: - length--; - continue; - default: - opsize = *ptr++; - if (opsize < 2) - goto done_opts; - if (opsize > length) - goto done_opts; - - if (opcode == TCPOPT_MD5SIG) { - hash_location = ptr; - goto done_opts; - } - } - ptr += opsize-2; - length -= opsize; - } -done_opts: /* We've parsed the options - do we have a hash? */ if (!hash_expected && !hash_location) return 0; diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 715965f0fac0..dd4ddb30a3a9 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -844,43 +844,12 @@ static int tcp_v6_inbound_md5_hash (struct sock *sk, struct sk_buff *skb) struct tcp_md5sig_key *hash_expected; struct ipv6hdr *ip6h = ipv6_hdr(skb); struct tcphdr *th = tcp_hdr(skb); - int length = (th->doff << 2) - sizeof (*th); int genhash; - u8 *ptr; u8 newhash[16]; hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr); + hash_location = tcp_parse_md5sig_option(th); - /* If the TCP option is too short, we can short cut */ - if (length < TCPOLEN_MD5SIG) - return hash_expected ? 1 : 0; - - /* parse options */ - ptr = (u8*)(th + 1); - while (length > 0) { - int opcode = *ptr++; - int opsize; - - switch(opcode) { - case TCPOPT_EOL: - goto done_opts; - case TCPOPT_NOP: - length--; - continue; - default: - opsize = *ptr++; - if (opsize < 2 || opsize > length) - goto done_opts; - if (opcode == TCPOPT_MD5SIG) { - hash_location = ptr; - goto done_opts; - } - } - ptr += opsize - 2; - length -= opsize; - } - -done_opts: /* do we have a hash as expected? */ if (!hash_expected) { if (!hash_location) -- 2.20.1