ipv6: make lookups simpler and faster

[~andy/linux] / net / l2tp / l2tp_core.c

diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c
index feae495a0a30accd9eb5a88baf1c23095bb38d66..9af77d9c0ec9b7327c275feeacc6766c7681f54d 100644 (file)
--- a/net/l2tp/l2tp_core.c
+++ b/net/l2tp/l2tp_core.c
@@ -115,6 +115,11 @@ struct l2tp_net {
 static void l2tp_session_set_header_len(struct l2tp_session *session, int version);
 static void l2tp_tunnel_free(struct l2tp_tunnel *tunnel);
 
+static inline struct l2tp_tunnel *l2tp_tunnel(struct sock *sk)
+{
+       return sk->sk_user_data;
+}
+
 static inline struct l2tp_net *l2tp_pernet(struct net *net)
 {
        BUG_ON(!net);
@@ -504,7 +509,7 @@ static inline int l2tp_verify_udp_checksum(struct sock *sk,
                return 0;
 
 #if IS_ENABLED(CONFIG_IPV6)
-       if (sk->sk_family == PF_INET6) {
+       if (sk->sk_family == PF_INET6 && !l2tp_tunnel(sk)->v4mapped) {
                if (!uh->check) {
                        LIMIT_NETDEBUG(KERN_INFO "L2TP: IPv6: checksum is 0\n");
                        return 1;
@@ -1128,7 +1133,7 @@ static int l2tp_xmit_core(struct l2tp_session *session, struct sk_buff *skb,
        /* Queue the packet to IP for output */
        skb->local_df = 1;
 #if IS_ENABLED(CONFIG_IPV6)
-       if (skb->sk->sk_family == PF_INET6)
+       if (skb->sk->sk_family == PF_INET6 && !tunnel->v4mapped)
                error = inet6_csk_xmit(skb, NULL);
        else
 #endif
@@ -1176,7 +1181,7 @@ static void l2tp_xmit_ipv6_csum(struct sock *sk, struct sk_buff *skb,
            !(skb_dst(skb)->dev->features & NETIF_F_IPV6_CSUM)) {
                __wsum csum = skb_checksum(skb, 0, udp_len, 0);
                skb->ip_summed = CHECKSUM_UNNECESSARY;
-               uh->check = csum_ipv6_magic(&np->saddr, &np->daddr, udp_len,
+               uh->check = csum_ipv6_magic(&np->saddr, &sk->sk_v6_daddr, udp_len,
                                            IPPROTO_UDP, csum);
                if (uh->check == 0)
                        uh->check = CSUM_MANGLED_0;
@@ -1184,7 +1189,7 @@ static void l2tp_xmit_ipv6_csum(struct sock *sk, struct sk_buff *skb,
                skb->ip_summed = CHECKSUM_PARTIAL;
                skb->csum_start = skb_transport_header(skb) - skb->head;
                skb->csum_offset = offsetof(struct udphdr, check);
-               uh->check = ~csum_ipv6_magic(&np->saddr, &np->daddr,
+               uh->check = ~csum_ipv6_magic(&np->saddr, &sk->sk_v6_daddr,
                                             udp_len, IPPROTO_UDP, 0);
        }
 }
@@ -1255,7 +1260,7 @@ int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len
 
                /* Calculate UDP checksum if configured to do so */
 #if IS_ENABLED(CONFIG_IPV6)
-               if (sk->sk_family == PF_INET6)
+               if (sk->sk_family == PF_INET6 && !tunnel->v4mapped)
                        l2tp_xmit_ipv6_csum(sk, skb, udp_len);
                else
 #endif
@@ -1304,10 +1309,9 @@ EXPORT_SYMBOL_GPL(l2tp_xmit_skb);
  */
 static void l2tp_tunnel_destruct(struct sock *sk)
 {
-       struct l2tp_tunnel *tunnel;
+       struct l2tp_tunnel *tunnel = l2tp_tunnel(sk);
        struct l2tp_net *pn;
 
-       tunnel = sk->sk_user_data;
        if (tunnel == NULL)
                goto end;
 
@@ -1675,7 +1679,7 @@ int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id, u32
        }
 
        /* Check if this socket has already been prepped */
-       tunnel = (struct l2tp_tunnel *)sk->sk_user_data;
+       tunnel = l2tp_tunnel(sk);
        if (tunnel != NULL) {
                /* This socket has already been prepped */
                err = -EBUSY;
@@ -1704,6 +1708,24 @@ int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id, u32
        if (cfg != NULL)
                tunnel->debug = cfg->debug;
 
+#if IS_ENABLED(CONFIG_IPV6)
+       if (sk->sk_family == PF_INET6) {
+               struct ipv6_pinfo *np = inet6_sk(sk);
+
+               if (ipv6_addr_v4mapped(&np->saddr) &&
+                   ipv6_addr_v4mapped(&sk->sk_v6_daddr)) {
+                       struct inet_sock *inet = inet_sk(sk);
+
+                       tunnel->v4mapped = true;
+                       inet->inet_saddr = np->saddr.s6_addr32[3];
+                       inet->inet_rcv_saddr = sk->sk_v6_rcv_saddr.s6_addr32[3];
+                       inet->inet_daddr = sk->sk_v6_daddr.s6_addr32[3];
+               } else {
+                       tunnel->v4mapped = false;
+               }
+       }
+#endif
+
        /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */
        tunnel->encap = encap;
        if (encap == L2TP_ENCAPTYPE_UDP) {
@@ -1712,7 +1734,7 @@ int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id, u32
                udp_sk(sk)->encap_rcv = l2tp_udp_encap_recv;
                udp_sk(sk)->encap_destroy = l2tp_udp_encap_destroy;
 #if IS_ENABLED(CONFIG_IPV6)
-               if (sk->sk_family == PF_INET6)
+               if (sk->sk_family == PF_INET6 && !tunnel->v4mapped)
                        udpv6_encap_enable();
                else
 #endif