Refactor update of IPv6 flow destination address for srcrt (RH) option

PATCH In review Arnaud Ebalard 3 participants 6 messages Jun 1, 2010 – Jun 2, 2010

Subsystems (5)

Networking Network drivers IPv4/IPv6 TCP +1 more subsystems

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Arnaud Ebalard

author

2010-06-01 16:20 UTC #0 lore raw

PATCH 1/1 Refactor update of IPv6 flow destination address for srcrt (RH) option

Hi,

While playing with associated code, I noticed there are more than a dozen occurrences of the following 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;
    }

Maybe this can be replaced with a helper (not sure about the name though).

Signed-off-by Arnaud Ebalard <[email protected]>

---
 include/net/ipv6.h               |   13 +++++++++++++
 net/dccp/ipv6.c                  |   24 +++---------------------
 net/ipv6/af_inet6.c              |    7 +------
 net/ipv6/datagram.c              |   16 +++-------------
 net/ipv6/inet6_connection_sock.c |    7 +------
 net/ipv6/raw.c                   |    8 +-------
 net/ipv6/syncookies.c            |    7 +------
 net/ipv6/tcp_ipv6.c              |   21 +++------------------
 net/ipv6/udp.c                   |    9 ++-------
 9 files changed, 28 insertions(+), 84 deletions(-)

include/net/ipv6.h +13 -0

index 2600b69..9edfa1c 100644
@@ -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)

net/dccp/ipv6.c +3 ~~-21~~

index 0916988..fc435ba 100644
@@ -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)

@@ -551,13 +545,7 @@ static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
 		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;

@@ -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)

net/ipv6/af_inet6.c +1 -6

index e733942..d6e6491 100644
@@ -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) {

net/ipv6/datagram.c +3 ~~-13~~

index 7126846..2fcba06 100644
@@ -42,6 +42,7 @@ int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	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)

net/ipv6/inet6_connection_sock.c +1 -6

index 0c5e3c3..505c8de 100644
@@ -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);

net/ipv6/raw.c +1 -7

index 4a4dcbe..91211bd 100644
@@ -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;

net/ipv6/syncookies.c +1 -6

index 34d1f06..7d27bc7 100644
@@ -245,12 +245,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
 		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;

net/ipv6/tcp_ipv6.c +3 ~~-18~~

index 2b7c3a1..2dcb536 100644
@@ -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);

@@ -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)

@@ -1398,12 +1388,7 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
 		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;

net/ipv6/udp.c +2 -7

index 87be586..a46ad07 100644
@@ -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;

Signature · 1 line

1.7.1

Arnaud Ebalard

author

2010-06-01 19:17 UTC #1 lore raw

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,

Quoted 1 line

From 50e59bf48323777a05476e0d094f15b67194f0bd Mon Sep 17 00:00:00 2001

From: Arnaud Ebalard <[email protected]>
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 <[email protected]>

---
 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(-)

include/net/ipv6.h +13 -0

index 2600b69..9edfa1c 100644
@@ -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)

net/dccp/ipv6.c +6 ~~-24~~

index 0916988..38151db 100644
@@ -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)

net/ipv6/af_inet6.c +2 -7

index e733942..9df2373 100644
@@ -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) {

net/ipv6/datagram.c +4 ~~-14~~

index 7126846..378fd58 100644
@@ -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)

net/ipv6/inet6_connection_sock.c +2 -7

index 0c5e3c3..14b5ec5 100644
@@ -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);

net/ipv6/raw.c +2 -8

index 4a4dcbe..f161a54 100644
@@ -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;

net/ipv6/syncookies.c +2 -7

index 34d1f06..edcaa92 100644
@@ -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;

net/ipv6/tcp_ipv6.c +6 ~~-21~~

index 2b7c3a1..212315a 100644
@@ -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;

net/ipv6/udp.c +3 -8

index 87be586..33aa47c 100644
@@ -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;

Signature · 1 line

1.7.1

Joe Perches

2010-06-01 20:08 UTC #2 lore raw

Quoted 7 lines · Arnaud Ebalard

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.

Quoted 5 lines

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.

[]

include/net/ipv6.h static inline void ipv6_addr_copy(struct in6_addr *a1, const struct in6_addr *a2 · line 305

Quoted 13 lines

include/net/ipv6.h +13 -0

+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;
+}
+

Should this be inline? Maybe it'd be better moved to exthdrs.c

Perhaps this is clearer as something like:

/**
* fl6_update_dst - update flow destination address
*
* @fl: flowlabel fl_dst to update
* @opt: struct ipv6_txoptions
* @orig: original fl_dst if modified
*
* Returns NULL if no txoptions or no srcrt, otherwise
* returns orig and initial value of fl->fl6_dst set in orig */
struct in6_addr *fl6_update_dst(struct ip6_flowlabel *fl,
const struct ipv6_txoptions *opt, struct in6_addr *orig)

{
	if (!opt || !opt->srcrt)
		return NULL;

	ipv6_addr_copy(orig, &fl->fl6_dst);
	ipv6_addr_copy(&fl->fl6_dst, ((struct rt0_hdr *)opt->srcrt)->addr);
	return orig;
}

Arnaud Ebalard

author

2010-06-01 21:58 UTC #3 lore raw

Hi,

Quoted 7 lines · Joe Perches

Quoted 7 lines

include/net/ipv6.h +7 -0

+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);

Quoted 8 lines

include/net/ipv6.h static inline void ipv6_addr_copy(struct in6_addr *a1, const struct in6_addr *a2 · line 305
Quoted 6 lines
include/net/ipv6.h +6 -0
+		ipv6_addr_copy(fl6dst, rt0->addr);
+		return final;
+	}
+	return NULL;
+}
+
Should this be inline? Maybe it'd be better moved to exthdrs.c

I thought it was small enough to keep it inline in ipv6.h but removing the inline and moving it to exthdrs.c makes sense.

Quoted 15 lines

Perhaps this is clearer as something like:
/**
* fl6_update_dst - update flow destination address
*
* @fl: flowlabel fl_dst to update
* @opt: struct ipv6_txoptions
* @orig: original fl_dst if modified
*
* Returns NULL if no txoptions or no srcrt, otherwise
* returns orig and initial value of fl->fl6_dst set in orig */
struct in6_addr *fl6_update_dst(struct ip6_flowlabel *fl,
const struct ipv6_txoptions *opt, struct in6_addr *orig)

Quoted 8 lines

{
	if (!opt || !opt->srcrt)
		return NULL;

	ipv6_addr_copy(orig, &fl->fl6_dst);
	ipv6_addr_copy(&fl->fl6_dst, ((struct rt0_hdr *)opt->srcrt)->addr);
	return orig;
}

I'll send an updated new version tomorrow, i.e. in a few hours (with s/ip6_flowlabel/flowi/).

Thanks for your feedback.

Cheers,

Arnaud Ebalard

author

2010-06-02 07:35 UTC #4 lore raw

Re: [PATCHv3] Refactor update of IPv6 flowi destination address for srcrt (RH) option

In reply to Joe Perches

Hi,

Here is a v3 based on the comments I received from Joe. The helper is now in exthdrs.c (no more inline) and has a proper name.

Applies on net-2.6. Tested on 2.6.34.

Cheers,

Quoted 1 line

From ec9c9695345f4821060a78bd3243cdfeaa852897 Mon Sep 17 00:00:00 2001

From: Arnaud Ebalard <[email protected]>
Date: Wed, 2 Jun 2010 09:25:27 +0200
Subject: [PATCH] Refactor update of IPv6 flowi 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 <[email protected]>

---
 include/net/ipv6.h               |    4 ++++
 net/dccp/ipv6.c                  |   30 ++++++------------------------
 net/ipv6/af_inet6.c              |    9 ++-------
 net/ipv6/datagram.c              |   18 ++++--------------
 net/ipv6/exthdrs.c               |   24 ++++++++++++++++++++++++
 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 +++--------
 10 files changed, 55 insertions(+), 96 deletions(-)

include/net/ipv6.h +4 -0

index 2600b69..f5808d5 100644
@@ -551,6 +551,10 @@ extern int 			ipv6_ext_hdr(u8 nexthdr);
 
 extern int ipv6_find_tlv(struct sk_buff *skb, int offset, int type);
 
+extern struct in6_addr *fl6_update_dst(struct flowi *fl,
+				       const struct ipv6_txoptions *opt,
+				       struct in6_addr *orig);
+
 /*
  *	socket options (ipv6_sockglue.c)
  */

net/dccp/ipv6.c +6 ~~-24~~

index 0916988..6e3f325 100644
@@ -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 = fl6_update_dst(&fl, opt, &final);
 
 	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 = fl6_update_dst(&fl, opt, &final);
 		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 = fl6_update_dst(&fl, np->opt, &final);
 
 	err = ip6_dst_lookup(sk, &dst, &fl);
 	if (err)

net/ipv6/af_inet6.c +2 -7

index e733942..94b1b9c 100644
@@ -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 = fl6_update_dst(&fl, np->opt, &final);
 
 		err = ip6_dst_lookup(sk, &dst, &fl);
 		if (err) {

net/ipv6/datagram.c +4 ~~-14~~

index 7126846..7d929a2 100644
@@ -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 = fl6_update_dst(&fl, opt, &final);
 
 	err = ip6_dst_lookup(sk, &dst, &fl);
 	if (err)

net/ipv6/exthdrs.c +24 -0

index 8a659f9..853a633 100644
@@ -874,3 +874,27 @@ struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
 	return opt;
 }
 
+/**
+ * fl6_update_dst - update flowi destination address with info given
+ *                  by srcrt option, if any.
+ *
+ * @fl: flowi for which fl6_dst is to be updated
+ * @opt: struct ipv6_txoptions in which to look for srcrt opt
+ * @orig: copy of original fl6_dst address if modified
+ *
+ * Returns NULL if no txoptions or no srcrt, otherwise returns orig
+ * and initial value of fl->fl6_dst set in orig
+ */
+struct in6_addr *fl6_update_dst(struct flowi *fl,
+				const struct ipv6_txoptions *opt,
+				struct in6_addr *orig)
+{
+	if (!opt || !opt->srcrt)
+		return NULL;
+
+	ipv6_addr_copy(orig, &fl->fl6_dst);
+	ipv6_addr_copy(&fl->fl6_dst, ((struct rt0_hdr *)opt->srcrt)->addr);
+	return orig;
+}
+
+EXPORT_SYMBOL_GPL(fl6_update_dst);

net/ipv6/inet6_connection_sock.c +2 -7

index 0c5e3c3..8a16280 100644
@@ -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 = fl6_update_dst(&fl, np->opt, &final);
 
 	dst = __inet6_csk_dst_check(sk, np->dst_cookie);

net/ipv6/raw.c +2 -8

index 4a4dcbe..864eb8e 100644
@@ -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 = fl6_update_dst(&fl, opt, &final);
 
 	if (!fl.oif && ipv6_addr_is_multicast(&fl.fl6_dst))
 		fl.oif = np->mcast_oif;

net/ipv6/syncookies.c +2 -7

index 34d1f06..1238370 100644
@@ -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 = fl6_update_dst(&fl, np->opt, &final);
 		ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr);
 		fl.oif = sk->sk_bound_dev_if;
 		fl.mark = sk->sk_mark;

net/ipv6/tcp_ipv6.c +6 ~~-21~~

index 2b7c3a1..e487080 100644
@@ -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 = fl6_update_dst(&fl, np->opt, &final);
 
 	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 = fl6_update_dst(&fl, opt, &final);
 
 	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 = fl6_update_dst(&fl, opt, &final);
 		ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr);
 		fl.oif = sk->sk_bound_dev_if;
 		fl.mark = sk->sk_mark;

net/ipv6/udp.c +3 -8

index 87be586..1dd1aff 100644
@@ -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 = fl6_update_dst(&fl, opt, &final);
+	if (final_p)
 		connected = 0;
-	}
 
 	if (!fl.oif && ipv6_addr_is_multicast(&fl.fl6_dst)) {
 		fl.oif = np->mcast_oif;

Signature · 1 line

1.7.1

David Miller

maintainer

2010-06-02 14:08 UTC #5 lore raw

Re: [PATCHv3] Refactor update of IPv6 flowi destination address for srcrt (RH) option

From: [email protected] (Arnaud Ebalard)
Date: Wed, 02 Jun 2010 09:35:01 +0200

Quoted 4 lines

Here is a v3 based on the comments I received from Joe. The helper is now in exthdrs.c (no more inline) and has a proper name.
Applies on net-2.6. Tested on 2.6.34.

Looks good, applied to net-next-2.6, thanks.