[IPSEC]: Fix bogus usage of u64 on input sequence number

Al Viro spotted a bogus use of u64 on the input sequence number which
is big-endian.  This patch fixes it by giving the input sequence number
its own member in the xfrm_skb_cb structure.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/xfrm.h

@@ -508,7 +508,10 @@ struct xfrm_skb_cb {
         } header;
 
         /* Sequence number for replay protection. */
-        u64 seq;
+	union {
+		u64 output;
+		__be32 input;
+	} seq;
 };
 
 #define XFRM_SKB_CB(__skb) ((struct xfrm_skb_cb *)&((__skb)->cb[0]))

net/ipv4/ah4.c

@@ -96,7 +96,7 @@ static int ah_output(struct xfrm_state *x, struct sk_buff *skb)
 
 	ah->reserved = 0;
 	ah->spi = x->id.spi;
-	ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq);
+	ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output);
 
 	spin_lock_bh(&x->lock);
 	err = ah_mac_digest(ahp, skb, ah->auth_data);

net/ipv4/esp4.c

@@ -199,7 +199,7 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
 	}
 
 	esph->spi = x->id.spi;
-	esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq);
+	esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output);
 
 	sg_init_table(sg, nfrags);
 	skb_to_sgvec(skb, sg,
@@ -210,7 +210,8 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
 	aead_givcrypt_set_callback(req, 0, esp_output_done, skb);
 	aead_givcrypt_set_crypt(req, sg, sg, clen, iv);
 	aead_givcrypt_set_assoc(req, asg, sizeof(*esph));
-	aead_givcrypt_set_giv(req, esph->enc_data, XFRM_SKB_CB(skb)->seq);
+	aead_givcrypt_set_giv(req, esph->enc_data,
+			      XFRM_SKB_CB(skb)->seq.output);
 
 	ESP_SKB_CB(skb)->tmp = tmp;
 	err = crypto_aead_givencrypt(req);

net/ipv6/ah6.c

@@ -283,7 +283,7 @@ static int ah6_output(struct xfrm_state *x, struct sk_buff *skb)
 
 	ah->reserved = 0;
 	ah->spi = x->id.spi;
-	ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq);
+	ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output);
 
 	spin_lock_bh(&x->lock);
 	err = ah_mac_digest(ahp, skb, ah->auth_data);

net/ipv6/esp6.c

@@ -188,7 +188,7 @@ static int esp6_output(struct xfrm_state *x, struct sk_buff *skb)
 	*skb_mac_header(skb) = IPPROTO_ESP;
 
 	esph->spi = x->id.spi;
-	esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq);
+	esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output);
 
 	sg_init_table(sg, nfrags);
 	skb_to_sgvec(skb, sg,
@@ -199,7 +199,8 @@ static int esp6_output(struct xfrm_state *x, struct sk_buff *skb)
 	aead_givcrypt_set_callback(req, 0, esp_output_done, skb);
 	aead_givcrypt_set_crypt(req, sg, sg, clen, iv);
 	aead_givcrypt_set_assoc(req, asg, sizeof(*esph));
-	aead_givcrypt_set_giv(req, esph->enc_data, XFRM_SKB_CB(skb)->seq);
+	aead_givcrypt_set_giv(req, esph->enc_data,
+			      XFRM_SKB_CB(skb)->seq.output);
 
 	ESP_SKB_CB(skb)->tmp = tmp;
 	err = crypto_aead_givencrypt(req);

net/xfrm/xfrm_input.c

@@ -109,7 +109,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 	if (encap_type < 0) {
 		async = 1;
 		x = xfrm_input_state(skb);
-		seq = XFRM_SKB_CB(skb)->seq;
+		seq = XFRM_SKB_CB(skb)->seq.input;
 		goto resume;
 	}
 
@@ -175,7 +175,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 
 		spin_unlock(&x->lock);
 
-		XFRM_SKB_CB(skb)->seq = seq;
+		XFRM_SKB_CB(skb)->seq.input = seq;
 
 		nexthdr = x->type->input(x, skb);
 

net/xfrm/xfrm_output.c

@@ -62,7 +62,7 @@ static int xfrm_output_one(struct sk_buff *skb, int err)
 		}
 
 		if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
-			XFRM_SKB_CB(skb)->seq = ++x->replay.oseq;
+			XFRM_SKB_CB(skb)->seq.output = ++x->replay.oseq;
 			if (unlikely(x->replay.oseq == 0)) {
 				XFRM_INC_STATS(LINUX_MIB_XFRMOUTSTATESEQERROR);
 				x->replay.oseq--;