tcp: use inet6_csk_route_req() in tcp_v6_send_synack()
With the recent change (earlier in this patch series) to set
flowi6_oif to treq->iif in inet6_csk_route_req(), the dst lookup in
these two functions is now identical, so tcp_v6_send_synack() can now
just call inet6_csk_route_req(), to reduce code duplication and keep
things closer to the IPv4 side, which is structured this way.
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 4e5fa5f..d1db0ca 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -485,34 +485,17 @@
struct inet6_request_sock *treq = inet6_rsk(req);
struct ipv6_pinfo *np = inet6_sk(sk);
struct sk_buff * skb;
- struct ipv6_txoptions *opt = NULL;
- struct in6_addr * final_p, final;
+ struct ipv6_txoptions *opt = np->opt;
struct flowi6 fl6;
struct dst_entry *dst;
- int err;
+ int err = -ENOMEM;
- memset(&fl6, 0, sizeof(fl6));
- fl6.flowi6_proto = IPPROTO_TCP;
- fl6.daddr = treq->rmt_addr;
- fl6.saddr = treq->loc_addr;
- fl6.flowlabel = 0;
- fl6.flowi6_oif = treq->iif;
- fl6.flowi6_mark = sk->sk_mark;
- fl6.fl6_dport = inet_rsk(req)->rmt_port;
- fl6.fl6_sport = inet_rsk(req)->loc_port;
- security_req_classify_flow(req, flowi6_to_flowi(&fl6));
-
- opt = np->opt;
- final_p = fl6_update_dst(&fl6, opt, &final);
-
- dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
- if (IS_ERR(dst)) {
- err = PTR_ERR(dst);
- dst = NULL;
+ dst = inet6_csk_route_req(sk, &fl6, req);
+ if (!dst)
goto done;
- }
+
skb = tcp_make_synack(sk, dst, req, rvp);
- err = -ENOMEM;
+
if (skb) {
__tcp_v6_send_check(skb, &treq->loc_addr, &treq->rmt_addr);
