[PATCH] knfsd: SUNRPC: support IPv6 addresses in RPC server's UDP receive path

Add support for IPv6 addresses in the RPC server's UDP receive path.

[akpm@linux-foundation.org: cleanups]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/sunrpc/svc.h

@@ -270,6 +270,11 @@ static inline struct sockaddr_in *svc_addr_in(struct svc_rqst *rqst)
 	return (struct sockaddr_in *) &rqst->rq_addr;
 }
 
+static inline struct sockaddr_in6 *svc_addr_in6(struct svc_rqst *rqst)
+{
+	return (struct sockaddr_in6 *) &rqst->rq_addr;
+}
+
 static inline struct sockaddr *svc_addr(struct svc_rqst *rqst)
 {
 	return (struct sockaddr *) &rqst->rq_addr;

net/sunrpc/svcsock.c

@@ -721,13 +721,53 @@ svc_write_space(struct sock *sk)
 	}
 }
 
+static void svc_udp_get_sender_address(struct svc_rqst *rqstp,
+					struct sk_buff *skb)
+{
+	switch (rqstp->rq_sock->sk_sk->sk_family) {
+	case AF_INET: {
+		/* this seems to come from net/ipv4/udp.c:udp_recvmsg */
+			struct sockaddr_in *sin = svc_addr_in(rqstp);
+
+			sin->sin_family = AF_INET;
+			sin->sin_port = skb->h.uh->source;
+			sin->sin_addr.s_addr = skb->nh.iph->saddr;
+			rqstp->rq_addrlen = sizeof(struct sockaddr_in);
+			/* Remember which interface received this request */
+			rqstp->rq_daddr.addr.s_addr = skb->nh.iph->daddr;
+		}
+		break;
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+	case AF_INET6: {
+		/* this is derived from net/ipv6/udp.c:udpv6_recvmesg */
+			struct sockaddr_in6 *sin6 = svc_addr_in6(rqstp);
+
+			sin6->sin6_family = AF_INET6;
+			sin6->sin6_port = skb->h.uh->source;
+			sin6->sin6_flowinfo = 0;
+			sin6->sin6_scope_id = 0;
+			if (ipv6_addr_type(&sin6->sin6_addr) &
+							IPV6_ADDR_LINKLOCAL)
+				sin6->sin6_scope_id = IP6CB(skb)->iif;
+			ipv6_addr_copy(&sin6->sin6_addr,
+							&skb->nh.ipv6h->saddr);
+			rqstp->rq_addrlen = sizeof(struct sockaddr_in);
+			/* Remember which interface received this request */
+			ipv6_addr_copy(&rqstp->rq_daddr.addr6,
+							&skb->nh.ipv6h->saddr);
+		}
+		break;
+#endif
+	}
+	return;
+}
+
 /*
  * Receive a datagram from a UDP socket.
  */
 static int
 svc_udp_recvfrom(struct svc_rqst *rqstp)
 {
-	struct sockaddr_in *sin = svc_addr_in(rqstp);
 	struct svc_sock	*svsk = rqstp->rq_sock;
 	struct svc_serv	*serv = svsk->sk_server;
 	struct sk_buff	*skb;
@@ -785,16 +825,9 @@ svc_udp_recvfrom(struct svc_rqst *rqstp)
 	len  = skb->len - sizeof(struct udphdr);
 	rqstp->rq_arg.len = len;
 
-	rqstp->rq_prot        = IPPROTO_UDP;
-
-	/* Get sender address */
-	sin->sin_family = AF_INET;
-	sin->sin_port = skb->h.uh->source;
-	sin->sin_addr.s_addr = skb->nh.iph->saddr;
-	rqstp->rq_addrlen = sizeof(struct sockaddr_in);
+	rqstp->rq_prot = IPPROTO_UDP;
 
-	/* Remember which interface received this request */
-	rqstp->rq_daddr.addr.s_addr = skb->nh.iph->daddr;
+	svc_udp_get_sender_address(rqstp, skb);
 
 	if (skb_is_nonlinear(skb)) {
 		/* we have to copy */