From 626e264dd1989bdc98a5eaf2e059af4dba07ac4f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= Date: Thu, 9 Oct 2008 14:42:40 -0700 Subject: [PATCH] tcpv6: combine tcp_v6_send_(reset|ack) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit $ codiff tcp_ipv6.o.old tcp_ipv6.o.new net/ipv6/tcp_ipv6.c: tcp_v6_md5_hash_hdr | -144 tcp_v6_send_ack | -585 tcp_v6_send_reset | -540 3 functions changed, 1269 bytes removed, diff: -1269 net/ipv6/tcp_ipv6.c: tcp_v6_send_response | +791 1 function changed, 791 bytes added, diff: +791 tcp_ipv6.o.new: 4 functions changed, 791 bytes added, 1269 bytes removed, diff: -478 I choose to leave the reset related netns comment in place (not the one that is killed) as I cannot understand its English so it's a bit hard for me to evaluate its usefulness :-). Signed-off-by: Ilpo Järvinen Signed-off-by: David S. Miller --- net/ipv6/tcp_ipv6.c | 151 ++++++++++++++------------------------------ 1 file changed, 46 insertions(+), 105 deletions(-) diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 1941c5c888d3..13c65144a00a 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -942,110 +942,8 @@ static int tcp_v6_gso_send_check(struct sk_buff *skb) return 0; } -static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb) -{ - struct tcphdr *th = tcp_hdr(skb), *t1; - struct sk_buff *buff; - struct flowi fl; - struct net *net = dev_net(skb->dst->dev); - struct sock *ctl_sk = net->ipv6.tcp_sk; - unsigned int tot_len = sizeof(struct tcphdr); - __be32 *topt; -#ifdef CONFIG_TCP_MD5SIG - struct tcp_md5sig_key *key; -#endif - - if (th->rst) - return; - - if (!ipv6_unicast_destination(skb)) - return; - -#ifdef CONFIG_TCP_MD5SIG - if (sk) - key = tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr); - else - key = NULL; - - if (key) - tot_len += TCPOLEN_MD5SIG_ALIGNED; -#endif - - /* - * We need to grab some memory, and put together an RST, - * and then put it into the queue to be sent. - */ - - buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len, - GFP_ATOMIC); - if (buff == NULL) - return; - - skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len); - - t1 = (struct tcphdr *) skb_push(buff, tot_len); - - /* Swap the send and the receive. */ - memset(t1, 0, sizeof(*t1)); - t1->dest = th->source; - t1->source = th->dest; - t1->doff = tot_len / 4; - t1->rst = 1; - - if(th->ack) { - t1->seq = th->ack_seq; - } else { - t1->ack = 1; - t1->ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin - + skb->len - (th->doff<<2)); - } - - topt = (__be32 *)(t1 + 1); - -#ifdef CONFIG_TCP_MD5SIG - if (key) { - *topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | - (TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG); - tcp_v6_md5_hash_hdr((__u8 *)topt, key, - &ipv6_hdr(skb)->saddr, - &ipv6_hdr(skb)->daddr, t1); - } -#endif - - buff->csum = csum_partial((char *)t1, tot_len, 0); - - memset(&fl, 0, sizeof(fl)); - ipv6_addr_copy(&fl.fl6_dst, &ipv6_hdr(skb)->saddr); - ipv6_addr_copy(&fl.fl6_src, &ipv6_hdr(skb)->daddr); - - t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst, - tot_len, IPPROTO_TCP, - buff->csum); - - fl.proto = IPPROTO_TCP; - fl.oif = inet6_iif(skb); - fl.fl_ip_dport = t1->dest; - fl.fl_ip_sport = t1->source; - security_skb_classify_flow(skb, &fl); - - /* Pass a socket to ip6_dst_lookup either it is for RST - * Underlying function will use this to retrieve the network - * namespace - */ - if (!ip6_dst_lookup(ctl_sk, &buff->dst, &fl)) { - if (xfrm_lookup(&buff->dst, &fl, NULL, 0) >= 0) { - ip6_xmit(ctl_sk, buff, &fl, NULL, 0); - TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS); - TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS); - return; - } - } - - kfree_skb(buff); -} - -static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts, - struct tcp_md5sig_key *key) +static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win, + u32 ts, struct tcp_md5sig_key *key, int rst) { struct tcphdr *th = tcp_hdr(skb), *t1; struct sk_buff *buff; @@ -1078,7 +976,8 @@ static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 t1->doff = tot_len / 4; t1->seq = htonl(seq); t1->ack_seq = htonl(ack); - t1->ack = 1; + t1->ack = !rst || !th->ack; + t1->rst = rst; t1->window = htons(win); topt = (__be32 *)(t1 + 1); @@ -1116,10 +1015,16 @@ static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 fl.fl_ip_sport = t1->source; security_skb_classify_flow(skb, &fl); + /* Pass a socket to ip6_dst_lookup either it is for RST + * Underlying function will use this to retrieve the network + * namespace + */ if (!ip6_dst_lookup(ctl_sk, &buff->dst, &fl)) { if (xfrm_lookup(&buff->dst, &fl, NULL, 0) >= 0) { ip6_xmit(ctl_sk, buff, &fl, NULL, 0); TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS); + if (rst) + TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS); return; } } @@ -1127,6 +1032,42 @@ static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 kfree_skb(buff); } +static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb) +{ + struct tcphdr *th = tcp_hdr(skb); + u32 seq = 0, ack_seq = 0; +#ifdef CONFIG_TCP_MD5SIG + struct tcp_md5sig_key *key; +#endif + + if (th->rst) + return; + + if (!ipv6_unicast_destination(skb)) + return; + +#ifdef CONFIG_TCP_MD5SIG + if (sk) + key = tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr); + else + key = NULL; +#endif + + if (th->ack) + seq = ntohl(th->ack_seq); + else + ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len - + (th->doff << 2); + + tcp_v6_send_response(skb, seq, ack_seq, 0, 0, key, 1); +} + +static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts, + struct tcp_md5sig_key *key) +{ + tcp_v6_send_response(skb, seq, ack, win, ts, key, 0); +} + static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) { struct inet_timewait_sock *tw = inet_twsk(sk);