From mboxrd@z Thu Jan 1 00:00:00 1970 From: arno@natisbad.org (Arnaud Ebalard) Subject: Re: [PATCHv2] Refactor update of IPv6 flow destination address for srcrt (RH) option Date: Tue, 01 Jun 2010 21:17:33 +0200 Message-ID: <8739x6d0ky.fsf@small.ssi.corp> References: <87wruid8rx.fsf@small.ssi.corp> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: YOSHIFUJI Hideaki / =?utf-8?B?5ZCJ6Jek6Iux5piO?= , To: "David S. Miller" Return-path: Received: from copper.chdir.org ([88.191.97.87]:55101 "EHLO copper.chdir.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752985Ab0FATRq (ORCPT ); Tue, 1 Jun 2010 15:17:46 -0400 Sender: netdev-owner@vger.kernel.org List-ID: Hi, I received a comment (privately) about the fact that the transform isn't equivalent as its sets final_p in all cases now, and asked if it matters? It does not: in current code, final_p is always initialized to NULL when it is declared. I also verified it is not used by anything between the declaration and the code I replace by the helper. In fact, one additional thing which can be done is to remove the initialization final_p to NULL when it is declared. The updated version below does that. Patch is against net-2.6. Tested on 2.6.34. Cheers, a+ >>From 50e59bf48323777a05476e0d094f15b67194f0bd Mon Sep 17 00:00:00 2001 From: Arnaud Ebalard Date: Tue, 1 Jun 2010 19:40:54 +0200 Subject: [PATCHv2] Refactor update of IPv6 flow destination address for srcrt (RH) option There are more than a dozen occurrences of following code in the IPv6 stack: if (opt && opt->srcrt) { struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt; ipv6_addr_copy(&final, &fl.fl6_dst); ipv6_addr_copy(&fl.fl6_dst, rt0->addr); final_p = &final; } Replace those with a helper. Note that the helper overrides final_p in all cases. This is ok as final_p was previously initialized to NULL when declared. Signed-off-by: Arnaud Ebalard --- include/net/ipv6.h | 13 +++++++++++++ net/dccp/ipv6.c | 30 ++++++------------------------ net/ipv6/af_inet6.c | 9 ++------- net/ipv6/datagram.c | 18 ++++-------------- net/ipv6/inet6_connection_sock.c | 9 ++------- net/ipv6/raw.c | 10 ++-------- net/ipv6/syncookies.c | 9 ++------- net/ipv6/tcp_ipv6.c | 27 ++++++--------------------- net/ipv6/udp.c | 11 +++-------- 9 files changed, 40 insertions(+), 96 deletions(-) diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 2600b69..9edfa1c 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -290,6 +290,19 @@ static inline void ipv6_addr_copy(struct in6_addr *a1, const struct in6_addr *a2 memcpy(a1, a2, sizeof(struct in6_addr)); } +static inline struct in6_addr *srcrt_dst_flow_update(struct in6_addr *final, + struct in6_addr *fl6dst, + const struct ipv6_txoptions *opt) +{ + if (opt && opt->srcrt) { + const struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt; + ipv6_addr_copy(final, fl6dst); + ipv6_addr_copy(fl6dst, rt0->addr); + return final; + } + return NULL; +} + static inline void ipv6_addr_prefix(struct in6_addr *pfx, const struct in6_addr *addr, int plen) diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c index 0916988..38151db 100644 --- a/net/dccp/ipv6.c +++ b/net/dccp/ipv6.c @@ -248,7 +248,7 @@ static int dccp_v6_send_response(struct sock *sk, struct request_sock *req, struct ipv6_pinfo *np = inet6_sk(sk); struct sk_buff *skb; struct ipv6_txoptions *opt = NULL; - struct in6_addr *final_p = NULL, final; + struct in6_addr *final_p, final; struct flowi fl; int err = -1; struct dst_entry *dst; @@ -265,13 +265,7 @@ static int dccp_v6_send_response(struct sock *sk, struct request_sock *req, opt = np->opt; - if (opt != NULL && opt->srcrt != NULL) { - const struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt; - - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } + final_p = srcrt_dst_flow_update(&final, &fl.fl6_dst, opt); err = ip6_dst_lookup(sk, &dst, &fl); if (err) @@ -545,19 +539,13 @@ static struct sock *dccp_v6_request_recv_sock(struct sock *sk, goto out_overflow; if (dst == NULL) { - struct in6_addr *final_p = NULL, final; + struct in6_addr *final_p, final; struct flowi fl; memset(&fl, 0, sizeof(fl)); fl.proto = IPPROTO_DCCP; ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr); - if (opt != NULL && opt->srcrt != NULL) { - const struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt; - - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } + final_p = srcrt_dst_flow_update(&final, &fl.fl6_dst, opt); ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr); fl.oif = sk->sk_bound_dev_if; fl.fl_ip_dport = inet_rsk(req)->rmt_port; @@ -885,7 +873,7 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr, struct inet_sock *inet = inet_sk(sk); struct ipv6_pinfo *np = inet6_sk(sk); struct dccp_sock *dp = dccp_sk(sk); - struct in6_addr *saddr = NULL, *final_p = NULL, final; + struct in6_addr *saddr = NULL, *final_p, final; struct flowi fl; struct dst_entry *dst; int addr_type; @@ -988,13 +976,7 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr, fl.fl_ip_sport = inet->inet_sport; security_sk_classify_flow(sk, &fl); - if (np->opt != NULL && np->opt->srcrt != NULL) { - const struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt; - - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } + final_p = srcrt_dst_flow_update(&final, &fl.fl6_dst, np->opt); err = ip6_dst_lookup(sk, &dst, &fl); if (err) diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index e733942..9df2373 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -651,7 +651,7 @@ int inet6_sk_rebuild_header(struct sock *sk) if (dst == NULL) { struct inet_sock *inet = inet_sk(sk); - struct in6_addr *final_p = NULL, final; + struct in6_addr *final_p, final; struct flowi fl; memset(&fl, 0, sizeof(fl)); @@ -665,12 +665,7 @@ int inet6_sk_rebuild_header(struct sock *sk) fl.fl_ip_sport = inet->inet_sport; security_sk_classify_flow(sk, &fl); - if (np->opt && np->opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } + final_p = srcrt_dst_flow_update(&final, &fl.fl6_dst, np->opt); err = ip6_dst_lookup(sk, &dst, &fl); if (err) { diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c index 7126846..378fd58 100644 --- a/net/ipv6/datagram.c +++ b/net/ipv6/datagram.c @@ -38,10 +38,11 @@ int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; struct inet_sock *inet = inet_sk(sk); struct ipv6_pinfo *np = inet6_sk(sk); - struct in6_addr *daddr, *final_p = NULL, final; + struct in6_addr *daddr, *final_p, final; struct dst_entry *dst; struct flowi fl; struct ip6_flowlabel *flowlabel = NULL; + struct ipv6_txoptions *opt; int addr_type; int err; @@ -155,19 +156,8 @@ ipv4_connected: security_sk_classify_flow(sk, &fl); - if (flowlabel) { - if (flowlabel->opt && flowlabel->opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *) flowlabel->opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } - } else if (np->opt && np->opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } + opt = flowlabel ? flowlabel->opt : np->opt; + final_p = srcrt_dst_flow_update(&final, &fl.fl6_dst, opt); err = ip6_dst_lookup(sk, &dst, &fl); if (err) diff --git a/net/ipv6/inet6_connection_sock.c b/net/ipv6/inet6_connection_sock.c index 0c5e3c3..14b5ec5 100644 --- a/net/ipv6/inet6_connection_sock.c +++ b/net/ipv6/inet6_connection_sock.c @@ -185,7 +185,7 @@ int inet6_csk_xmit(struct sk_buff *skb) struct ipv6_pinfo *np = inet6_sk(sk); struct flowi fl; struct dst_entry *dst; - struct in6_addr *final_p = NULL, final; + struct in6_addr *final_p, final; memset(&fl, 0, sizeof(fl)); fl.proto = sk->sk_protocol; @@ -199,12 +199,7 @@ int inet6_csk_xmit(struct sk_buff *skb) fl.fl_ip_dport = inet->inet_dport; security_sk_classify_flow(sk, &fl); - if (np->opt && np->opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } + final_p = srcrt_dst_flow_update(&final, &fl.fl6_dst, np->opt); dst = __inet6_csk_dst_check(sk, np->dst_cookie); diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index 4a4dcbe..f161a54 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -725,7 +725,7 @@ static int rawv6_sendmsg(struct kiocb *iocb, struct sock *sk, { struct ipv6_txoptions opt_space; struct sockaddr_in6 * sin6 = (struct sockaddr_in6 *) msg->msg_name; - struct in6_addr *daddr, *final_p = NULL, final; + struct in6_addr *daddr, *final_p, final; struct inet_sock *inet = inet_sk(sk); struct ipv6_pinfo *np = inet6_sk(sk); struct raw6_sock *rp = raw6_sk(sk); @@ -847,13 +847,7 @@ static int rawv6_sendmsg(struct kiocb *iocb, struct sock *sk, if (ipv6_addr_any(&fl.fl6_src) && !ipv6_addr_any(&np->saddr)) ipv6_addr_copy(&fl.fl6_src, &np->saddr); - /* merge ip6_build_xmit from ip6_output */ - if (opt && opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } + final_p = srcrt_dst_flow_update(&final, &fl.fl6_dst, opt); if (!fl.oif && ipv6_addr_is_multicast(&fl.fl6_dst)) fl.oif = np->mcast_oif; diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c index 34d1f06..edcaa92 100644 --- a/net/ipv6/syncookies.c +++ b/net/ipv6/syncookies.c @@ -240,17 +240,12 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) * me if there is a preferred way. */ { - struct in6_addr *final_p = NULL, final; + struct in6_addr *final_p, final; struct flowi fl; memset(&fl, 0, sizeof(fl)); fl.proto = IPPROTO_TCP; ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr); - if (np->opt && np->opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } + final_p = srcrt_dst_flow_update(&final, &fl.fl6_dst, np->opt); ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr); fl.oif = sk->sk_bound_dev_if; fl.mark = sk->sk_mark; diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 2b7c3a1..212315a 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -129,7 +129,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, struct inet_connection_sock *icsk = inet_csk(sk); struct ipv6_pinfo *np = inet6_sk(sk); struct tcp_sock *tp = tcp_sk(sk); - struct in6_addr *saddr = NULL, *final_p = NULL, final; + struct in6_addr *saddr = NULL, *final_p, final; struct flowi fl; struct dst_entry *dst; int addr_type; @@ -250,12 +250,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, fl.fl_ip_dport = usin->sin6_port; fl.fl_ip_sport = inet->inet_sport; - if (np->opt && np->opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } + final_p = srcrt_dst_flow_update(&final, &fl.fl6_dst, np->opt); security_sk_classify_flow(sk, &fl); @@ -477,7 +472,7 @@ static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req, struct ipv6_pinfo *np = inet6_sk(sk); struct sk_buff * skb; struct ipv6_txoptions *opt = NULL; - struct in6_addr * final_p = NULL, final; + struct in6_addr * final_p, final; struct flowi fl; struct dst_entry *dst; int err = -1; @@ -494,12 +489,7 @@ static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req, security_req_classify_flow(req, &fl); opt = np->opt; - if (opt && opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } + final_p = srcrt_dst_flow_update(&final, &fl.fl6_dst, opt); err = ip6_dst_lookup(sk, &dst, &fl); if (err) @@ -1392,18 +1382,13 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb, goto out_overflow; if (dst == NULL) { - struct in6_addr *final_p = NULL, final; + struct in6_addr *final_p, final; struct flowi fl; memset(&fl, 0, sizeof(fl)); fl.proto = IPPROTO_TCP; ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr); - if (opt && opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; - } + final_p = srcrt_dst_flow_update(&final, &fl.fl6_dst, opt); ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr); fl.oif = sk->sk_bound_dev_if; fl.mark = sk->sk_mark; diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 87be586..33aa47c 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -927,7 +927,7 @@ int udpv6_sendmsg(struct kiocb *iocb, struct sock *sk, struct inet_sock *inet = inet_sk(sk); struct ipv6_pinfo *np = inet6_sk(sk); struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) msg->msg_name; - struct in6_addr *daddr, *final_p = NULL, final; + struct in6_addr *daddr, *final_p, final; struct ipv6_txoptions *opt = NULL; struct ip6_flowlabel *flowlabel = NULL; struct flowi fl; @@ -1097,14 +1097,9 @@ do_udp_sendmsg: ipv6_addr_copy(&fl.fl6_src, &np->saddr); fl.fl_ip_sport = inet->inet_sport; - /* merge ip6_build_xmit from ip6_output */ - if (opt && opt->srcrt) { - struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt; - ipv6_addr_copy(&final, &fl.fl6_dst); - ipv6_addr_copy(&fl.fl6_dst, rt0->addr); - final_p = &final; + final_p = srcrt_dst_flow_update(&final, &fl.fl6_dst, opt); + if (final_p) connected = 0; - } if (!fl.oif && ipv6_addr_is_multicast(&fl.fl6_dst)) { fl.oif = np->mcast_oif; -- 1.7.1