return err;
}
+static inline void syn_flood_warning(struct sk_buff *skb)
+{
+#ifdef CONFIG_SYN_COOKIES
+ if (sysctl_tcp_syncookies)
+ printk(KERN_INFO
+ "TCPv6: Possible SYN flooding on port %d. "
+ "Sending cookies.\n", ntohs(tcp_hdr(skb)->dest));
+ else
+#endif
+ printk(KERN_INFO
+ "TCPv6: Possible SYN flooding on port %d. "
+ "Dropping request.\n", ntohs(tcp_hdr(skb)->dest));
+}
+
static void tcp_v6_reqsk_destructor(struct request_sock *req)
{
if (inet6_rsk(req)->pktopts)
hp = tcp_get_md5sig_pool();
if (!hp) {
- printk(KERN_WARNING "%s(): hash pool not found...\n", __FUNCTION__);
+ printk(KERN_WARNING "%s(): hash pool not found...\n", __func__);
goto clear_hash_noput;
}
bp = &hp->md5_blk.ip6;
/* Now store the hash into the packet */
err = crypto_hash_init(desc);
if (err) {
- printk(KERN_WARNING "%s(): hash_init failed\n", __FUNCTION__);
+ printk(KERN_WARNING "%s(): hash_init failed\n", __func__);
goto clear_hash;
}
err = crypto_hash_update(desc, sg, nbytes);
if (err) {
- printk(KERN_WARNING "%s(): hash_update failed\n", __FUNCTION__);
+ printk(KERN_WARNING "%s(): hash_update failed\n", __func__);
goto clear_hash;
}
err = crypto_hash_final(desc, md5_hash);
if (err) {
- printk(KERN_WARNING "%s(): hash_final failed\n", __FUNCTION__);
+ printk(KERN_WARNING "%s(): hash_final failed\n", __func__);
goto clear_hash;
}
}
#endif
-static struct request_sock_ops tcp6_request_sock_ops __read_mostly = {
+struct request_sock_ops tcp6_request_sock_ops __read_mostly = {
.family = AF_INET6,
.obj_size = sizeof(struct tcp6_request_sock),
.rtx_syn_ack = tcp_v6_send_synack,
fl.fl_ip_sport = t1->source;
security_skb_classify_flow(skb, &fl);
- /* sk = NULL, but it is safe for now. RST socket required. */
- if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) {
+ /* Pass a socket to ip6_dst_lookup either it is for RST
+ * Underlying function will use this to retrieve the network
+ * namespace
+ */
+ if (!ip6_dst_lookup(tcp6_socket->sk, &buff->dst, &fl)) {
if (xfrm_lookup(&buff->dst, &fl, NULL, 0) >= 0) {
ip6_xmit(tcp6_socket->sk, buff, &fl, NULL, 0);
fl.fl_ip_sport = t1->source;
security_skb_classify_flow(skb, &fl);
- if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) {
+ if (!ip6_dst_lookup(tcp6_socket->sk, &buff->dst, &fl)) {
if (xfrm_lookup(&buff->dst, &fl, NULL, 0) >= 0) {
ip6_xmit(tcp6_socket->sk, buff, &fl, NULL, 0);
TCP_INC_STATS_BH(TCP_MIB_OUTSEGS);
return NULL;
}
-#if 0 /*def CONFIG_SYN_COOKIES*/
+#ifdef CONFIG_SYN_COOKIES
if (!th->rst && !th->syn && th->ack)
- sk = cookie_v6_check(sk, skb, &(IPCB(skb)->opt));
+ sk = cookie_v6_check(sk, skb);
#endif
return sk;
}
struct tcp_sock *tp = tcp_sk(sk);
struct request_sock *req = NULL;
__u32 isn = TCP_SKB_CB(skb)->when;
+#ifdef CONFIG_SYN_COOKIES
+ int want_cookie = 0;
+#else
+#define want_cookie 0
+#endif
if (skb->protocol == htons(ETH_P_IP))
return tcp_v4_conn_request(sk, skb);
if (!ipv6_unicast_destination(skb))
goto drop;
- /*
- * There are no SYN attacks on IPv6, yet...
- */
if (inet_csk_reqsk_queue_is_full(sk) && !isn) {
if (net_ratelimit())
- printk(KERN_INFO "TCPv6: dropping request, synflood is possible\n");
+ syn_flood_warning(skb);
+#ifdef CONFIG_SYN_COOKIES
+ if (sysctl_tcp_syncookies)
+ want_cookie = 1;
+ else
+#endif
goto drop;
}
tcp_parse_options(skb, &tmp_opt, 0);
+ if (want_cookie) {
+ tcp_clear_options(&tmp_opt);
+ tmp_opt.saw_tstamp = 0;
+ }
+
tmp_opt.tstamp_ok = tmp_opt.saw_tstamp;
tcp_openreq_init(req, &tmp_opt, skb);
treq = inet6_rsk(req);
ipv6_addr_copy(&treq->rmt_addr, &ipv6_hdr(skb)->saddr);
ipv6_addr_copy(&treq->loc_addr, &ipv6_hdr(skb)->daddr);
- TCP_ECN_create_request(req, tcp_hdr(skb));
treq->pktopts = NULL;
- if (ipv6_opt_accepted(sk, skb) ||
- np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
- np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
- atomic_inc(&skb->users);
- treq->pktopts = skb;
- }
- treq->iif = sk->sk_bound_dev_if;
+ if (!want_cookie)
+ TCP_ECN_create_request(req, tcp_hdr(skb));
+
+ if (want_cookie) {
+ isn = cookie_v6_init_sequence(sk, skb, &req->mss);
+ } else if (!isn) {
+ if (ipv6_opt_accepted(sk, skb) ||
+ np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
+ np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
+ atomic_inc(&skb->users);
+ treq->pktopts = skb;
+ }
+ treq->iif = sk->sk_bound_dev_if;
- /* So that link locals have meaning */
- if (!sk->sk_bound_dev_if &&
- ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL)
- treq->iif = inet6_iif(skb);
+ /* So that link locals have meaning */
+ if (!sk->sk_bound_dev_if &&
+ ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL)
+ treq->iif = inet6_iif(skb);
- if (isn == 0)
isn = tcp_v6_init_sequence(skb);
+ }
tcp_rsk(req)->snt_isn = isn;
if (tcp_v6_send_synack(sk, req))
goto drop;
- inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
- return 0;
+ if (!want_cookie) {
+ inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
+ return 0;
+ }
drop:
if (req)