Re: xfrm_input() and ->seq oddities
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: 2008-02-03 00:20:30
Subsystem:
networking [general], networking [ipsec], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Steffen Klassert, Herbert Xu, Linus Torvalds
On Sat, Feb 02, 2008 at 11:58:27PM +0000, Al Viro wrote:
What's going on with XFRM_SKB_CB(skb)->seq? Almost all users expect it to be u32 (feeding it to htonl()), except xfrm_input(). That one expects __be32 in there - check what it does to seq and you'll see. Moreover, it updates the sucker in a way that makes sense only for __be32.
My bad.
a) are we just missing ntohl() and htonl() in obvious places in xfrm_input()?
It's semantically correct. However, my mistake that I'm mixing the input sequence number which is network endian with the output sequence number which is host endian (and 64-bit).
b) WTF is it declared as 64bit, anyway?
For extended sequence numbers which we'll support soon (I hope). [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> Thanks, -- Visit Openswan at http://www.openswan.org/ Email: Herbert Xu ~{PmV>HI~} [off-list ref] Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt --
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index ac72116..eea7785 100644
--- a/include/net/xfrm.h
+++ b/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]))
diff --git a/net/ipv4/ah4.c b/net/ipv4/ah4.c
index 9d4555e..8219b7e 100644
--- a/net/ipv4/ah4.c
+++ b/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);
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index 258d176..091e670 100644
--- a/net/ipv4/esp4.c
+++ b/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);
diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index 379c8e0..2ff0c82 100644
--- a/net/ipv6/ah6.c
+++ b/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);
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 8e0f142..0ec1402 100644
--- a/net/ipv6/esp6.c
+++ b/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);
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index 4d6ebc6..62188c6 100644
--- a/net/xfrm/xfrm_input.c
+++ b/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);
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index fc69036..569d377 100644
--- a/net/xfrm/xfrm_output.c
+++ b/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--;