X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=net%2Fipv4%2Fsyncookies.c;h=4704f27f6c0b4f16d929668a9f043a96a57fd7ac;hb=7524d7d6de5d5d3f081de8cf5479819fad339661;hp=33016cc90f0b8a7add18555666a010f87bc550ab;hpb=a727fea99bf4b2addcd64c596735148117a7b37f;p=linux-2.6

diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
index 33016cc90f..4704f27f6c 100644
--- a/net/ipv4/syncookies.c
+++ b/net/ipv4/syncookies.c
@@ -10,8 +10,6 @@
  *      2 of the License, or (at your option) any later version.
  *
  *  $Id: syncookies.c,v 1.18 2002/02/01 22:01:04 davem Exp $
- *
- *  Missing: IPv6 support.
  */
 
 #include <linux/tcp.h>
@@ -23,22 +21,25 @@
 
 extern int sysctl_tcp_syncookies;
 
-static __u32 syncookie_secret[2][16-3+SHA_DIGEST_WORDS];
+__u32 syncookie_secret[2][16-3+SHA_DIGEST_WORDS];
+EXPORT_SYMBOL(syncookie_secret);
 
 static __init int init_syncookies(void)
 {
 	get_random_bytes(syncookie_secret, sizeof(syncookie_secret));
 	return 0;
 }
-module_init(init_syncookies);
+__initcall(init_syncookies);
 
 #define COOKIEBITS 24	/* Upper bits store count */
 #define COOKIEMASK (((__u32)1 << COOKIEBITS) - 1)
 
+static DEFINE_PER_CPU(__u32, cookie_scratch)[16 + 5 + SHA_WORKSPACE_WORDS];
+
 static u32 cookie_hash(__be32 saddr, __be32 daddr, __be16 sport, __be16 dport,
 		       u32 count, int c)
 {
-	__u32 tmp[16 + 5 + SHA_WORKSPACE_WORDS];
+	__u32 *tmp = __get_cpu_var(cookie_scratch);
 
 	memcpy(tmp + 3, syncookie_secret[c], sizeof(syncookie_secret[c]));
 	tmp[0] = (__force u32)saddr;
@@ -125,10 +126,11 @@ static __u16 const msstab[] = {
 __u32 cookie_v4_init_sequence(struct sock *sk, struct sk_buff *skb, __u16 *mssp)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
+	const struct iphdr *iph = ip_hdr(skb);
+	const struct tcphdr *th = tcp_hdr(skb);
 	int mssind;
 	const __u16 mss = *mssp;
 
-
 	tp->last_synq_overflow = jiffies;
 
 	/* XXX sort msstab[] by probability?  Binary search? */
@@ -138,9 +140,8 @@ __u32 cookie_v4_init_sequence(struct sock *sk, struct sk_buff *skb, __u16 *mssp)
 
 	NET_INC_STATS_BH(LINUX_MIB_SYNCOOKIESSENT);
 
-	return secure_tcp_syn_cookie(skb->nh.iph->saddr, skb->nh.iph->daddr,
-				     skb->h.th->source, skb->h.th->dest,
-				     ntohl(skb->h.th->seq),
+	return secure_tcp_syn_cookie(iph->saddr, iph->daddr,
+				     th->source, th->dest, ntohl(th->seq),
 				     jiffies / (HZ * 60), mssind);
 }
 
@@ -157,14 +158,13 @@ __u32 cookie_v4_init_sequence(struct sock *sk, struct sk_buff *skb, __u16 *mssp)
  */
 static inline int cookie_check(struct sk_buff *skb, __u32 cookie)
 {
-	__u32 seq;
-	__u32 mssind;
-
-	seq = ntohl(skb->h.th->seq)-1;
-	mssind = check_tcp_syn_cookie(cookie,
-				      skb->nh.iph->saddr, skb->nh.iph->daddr,
-				      skb->h.th->source, skb->h.th->dest,
-				      seq, jiffies / (HZ * 60), COUNTER_TRIES);
+	const struct iphdr *iph = ip_hdr(skb);
+	const struct tcphdr *th = tcp_hdr(skb);
+	__u32 seq = ntohl(th->seq) - 1;
+	__u32 mssind = check_tcp_syn_cookie(cookie, iph->saddr, iph->daddr,
+					    th->source, th->dest, seq,
+					    jiffies / (HZ * 60),
+					    COUNTER_TRIES);
 
 	return mssind < NUM_MSS ? msstab[mssind] + 1 : 0;
 }
@@ -191,14 +191,15 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb,
 	struct inet_request_sock *ireq;
 	struct tcp_request_sock *treq;
 	struct tcp_sock *tp = tcp_sk(sk);
-	__u32 cookie = ntohl(skb->h.th->ack_seq) - 1;
+	const struct tcphdr *th = tcp_hdr(skb);
+	__u32 cookie = ntohl(th->ack_seq) - 1;
 	struct sock *ret = sk;
 	struct request_sock *req;
 	int mss;
 	struct rtable *rt;
 	__u8 rcv_wscale;
 
-	if (!sysctl_tcp_syncookies || !skb->h.th->ack)
+	if (!sysctl_tcp_syncookies || !th->ack)
 		goto out;
 
 	if (time_after(jiffies, tp->last_synq_overflow + TCP_TIMEOUT_INIT) ||
@@ -220,12 +221,12 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb,
 	}
 	ireq = inet_rsk(req);
 	treq = tcp_rsk(req);
-	treq->rcv_isn		= ntohl(skb->h.th->seq) - 1;
+	treq->rcv_isn		= ntohl(th->seq) - 1;
 	treq->snt_isn		= cookie;
 	req->mss		= mss;
-	ireq->rmt_port		= skb->h.th->source;
-	ireq->loc_addr		= skb->nh.iph->daddr;
-	ireq->rmt_addr		= skb->nh.iph->saddr;
+	ireq->rmt_port		= th->source;
+	ireq->loc_addr		= ip_hdr(skb)->daddr;
+	ireq->rmt_addr		= ip_hdr(skb)->saddr;
 	ireq->opt		= NULL;
 
 	/* We throwed the options of the initial SYN away, so we hope
@@ -261,10 +262,10 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb,
 						.tos = RT_CONN_FLAGS(sk) } },
 				    .proto = IPPROTO_TCP,
 				    .uli_u = { .ports =
-					       { .sport = skb->h.th->dest,
-						 .dport = skb->h.th->source } } };
+					       { .sport = th->dest,
+						 .dport = th->source } } };
 		security_req_classify_flow(req, &fl);
-		if (ip_route_output_key(&rt, &fl)) {
+		if (ip_route_output_key(&init_net, &rt, &fl)) {
 			reqsk_free(req);
 			goto out;
 		}