From 4bf05eceecf2efb4c883e9e9b17825682e7330dd Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Mon, 27 Feb 2006 13:00:01 -0800 Subject: [IPSEC] esp: Kill unnecessary block and indentation We used to keep sg on the stack which is why the extra block was useful. We've long since stopped doing that so let's kill the block and save some indentation. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/ipv4/esp4.c | 87 ++++++++++++++++++++++++++++----------------------------- 1 file changed, 43 insertions(+), 44 deletions(-) (limited to 'net/ipv4/esp4.c') diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index 73bfcae8af9c..3f47419cb9c5 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -150,6 +150,10 @@ static int esp_input(struct xfrm_state *x, struct xfrm_decap_state *decap, struc int elen = skb->len - sizeof(struct ip_esp_hdr) - esp->conf.ivlen - alen; int nfrags; int encap_len = 0; + u8 nexthdr[2]; + struct scatterlist *sg; + u8 workbuf[60]; + int padlen; if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr))) goto out; @@ -185,61 +189,56 @@ static int esp_input(struct xfrm_state *x, struct xfrm_decap_state *decap, struc if (esp->conf.ivlen) crypto_cipher_set_iv(esp->conf.tfm, esph->enc_data, crypto_tfm_alg_ivsize(esp->conf.tfm)); - { - u8 nexthdr[2]; - struct scatterlist *sg = &esp->sgbuf[0]; - u8 workbuf[60]; - int padlen; + sg = &esp->sgbuf[0]; - if (unlikely(nfrags > ESP_NUM_FAST_SG)) { - sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC); - if (!sg) - goto out; - } - skb_to_sgvec(skb, sg, sizeof(struct ip_esp_hdr) + esp->conf.ivlen, elen); - crypto_cipher_decrypt(esp->conf.tfm, sg, sg, elen); - if (unlikely(sg != &esp->sgbuf[0])) - kfree(sg); + if (unlikely(nfrags > ESP_NUM_FAST_SG)) { + sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC); + if (!sg) + goto out; + } + skb_to_sgvec(skb, sg, sizeof(struct ip_esp_hdr) + esp->conf.ivlen, elen); + crypto_cipher_decrypt(esp->conf.tfm, sg, sg, elen); + if (unlikely(sg != &esp->sgbuf[0])) + kfree(sg); - if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2)) - BUG(); + if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2)) + BUG(); - padlen = nexthdr[0]; - if (padlen+2 >= elen) - goto out; + padlen = nexthdr[0]; + if (padlen+2 >= elen) + goto out; - /* ... check padding bits here. Silly. :-) */ + /* ... check padding bits here. Silly. :-) */ - if (x->encap && decap && decap->decap_type) { - struct esp_decap_data *encap_data; - struct udphdr *uh = (struct udphdr *) (iph+1); + if (x->encap && decap && decap->decap_type) { + struct esp_decap_data *encap_data; + struct udphdr *uh = (struct udphdr *) (iph+1); - encap_data = (struct esp_decap_data *) (decap->decap_data); - encap_data->proto = 0; + encap_data = (struct esp_decap_data *) (decap->decap_data); + encap_data->proto = 0; - switch (decap->decap_type) { - case UDP_ENCAP_ESPINUDP: - case UDP_ENCAP_ESPINUDP_NON_IKE: - encap_data->proto = AF_INET; - encap_data->saddr.a4 = iph->saddr; - encap_data->sport = uh->source; - encap_len = (void*)esph - (void*)uh; - break; + switch (decap->decap_type) { + case UDP_ENCAP_ESPINUDP: + case UDP_ENCAP_ESPINUDP_NON_IKE: + encap_data->proto = AF_INET; + encap_data->saddr.a4 = iph->saddr; + encap_data->sport = uh->source; + encap_len = (void*)esph - (void*)uh; + break; - default: - goto out; - } + default: + goto out; } - - iph->protocol = nexthdr[1]; - pskb_trim(skb, skb->len - alen - padlen - 2); - memcpy(workbuf, skb->nh.raw, iph->ihl*4); - skb->h.raw = skb_pull(skb, sizeof(struct ip_esp_hdr) + esp->conf.ivlen); - skb->nh.raw += encap_len + sizeof(struct ip_esp_hdr) + esp->conf.ivlen; - memcpy(skb->nh.raw, workbuf, iph->ihl*4); - skb->nh.iph->tot_len = htons(skb->len); } + iph->protocol = nexthdr[1]; + pskb_trim(skb, skb->len - alen - padlen - 2); + memcpy(workbuf, skb->nh.raw, iph->ihl*4); + skb->h.raw = skb_pull(skb, sizeof(struct ip_esp_hdr) + esp->conf.ivlen); + skb->nh.raw += encap_len + sizeof(struct ip_esp_hdr) + esp->conf.ivlen; + memcpy(skb->nh.raw, workbuf, iph->ihl*4); + skb->nh.iph->tot_len = htons(skb->len); + return 0; out: -- cgit v1.2.2 From 752c1f4c78fe86d0fd6497387f763306b0d8fc53 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Mon, 27 Feb 2006 13:00:40 -0800 Subject: [IPSEC]: Kill post_input hook and do NAT-T in esp_input directly The only reason post_input exists at all is that it gives us the potential to adjust the checksums incrementally in future which we ought to do. However, after thinking about it for a bit we can adjust the checksums without using this post_input stuff at all. The crucial point is that only the inner-most NAT-T SA needs to be considered when adjusting checksums. What's more, the checksum adjustment comes down to a single u32 due to the linearity of IP checksums. We just happen to have a spare u32 lying around in our skb structure :) When ip_summed is set to CHECKSUM_NONE on input, the value of skb->csum is currently unused. All we have to do is to make that the checksum adjustment and voila, there goes all the post_input and decap structures! I've left in the decap data structures for now since it's intricately woven into the sec_path stuff. We can kill them later too. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/ipv4/esp4.c | 128 +++++++++++++++++--------------------------------------- 1 file changed, 38 insertions(+), 90 deletions(-) (limited to 'net/ipv4/esp4.c') diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index 3f47419cb9c5..09590f356086 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -12,13 +12,6 @@ #include #include -/* decapsulation data for use when post-processing */ -struct esp_decap_data { - xfrm_address_t saddr; - __u16 sport; - __u8 proto; -}; - static int esp_output(struct xfrm_state *x, struct sk_buff *skb) { int err; @@ -210,25 +203,47 @@ static int esp_input(struct xfrm_state *x, struct xfrm_decap_state *decap, struc /* ... check padding bits here. Silly. :-) */ - if (x->encap && decap && decap->decap_type) { - struct esp_decap_data *encap_data; - struct udphdr *uh = (struct udphdr *) (iph+1); - - encap_data = (struct esp_decap_data *) (decap->decap_data); - encap_data->proto = 0; - - switch (decap->decap_type) { - case UDP_ENCAP_ESPINUDP: - case UDP_ENCAP_ESPINUDP_NON_IKE: - encap_data->proto = AF_INET; - encap_data->saddr.a4 = iph->saddr; - encap_data->sport = uh->source; - encap_len = (void*)esph - (void*)uh; - break; + if (x->encap) { + struct xfrm_encap_tmpl *encap = x->encap; + struct udphdr *uh; - default: + if (encap->encap_type != decap->decap_type) goto out; + + uh = (struct udphdr *)(iph + 1); + encap_len = (void*)esph - (void*)uh; + + /* + * 1) if the NAT-T peer's IP or port changed then + * advertize the change to the keying daemon. + * This is an inbound SA, so just compare + * SRC ports. + */ + if (iph->saddr != x->props.saddr.a4 || + uh->source != encap->encap_sport) { + xfrm_address_t ipaddr; + + ipaddr.a4 = iph->saddr; + km_new_mapping(x, &ipaddr, uh->source); + + /* XXX: perhaps add an extra + * policy check here, to see + * if we should allow or + * reject a packet from a + * different source + * address/port. + */ } + + /* + * 2) ignore UDP/TCP checksums in case + * of NAT-T in Transport Mode, or + * perform other post-processing fixes + * as per draft-ietf-ipsec-udp-encaps-06, + * section 3.1.2 + */ + if (!x->props.mode) + skb->ip_summed = CHECKSUM_UNNECESSARY; } iph->protocol = nexthdr[1]; @@ -245,63 +260,6 @@ out: return -EINVAL; } -static int esp_post_input(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb) -{ - - if (x->encap) { - struct xfrm_encap_tmpl *encap; - struct esp_decap_data *decap_data; - - encap = x->encap; - decap_data = (struct esp_decap_data *)(decap->decap_data); - - /* first, make sure that the decap type == the encap type */ - if (encap->encap_type != decap->decap_type) - return -EINVAL; - - switch (encap->encap_type) { - default: - case UDP_ENCAP_ESPINUDP: - case UDP_ENCAP_ESPINUDP_NON_IKE: - /* - * 1) if the NAT-T peer's IP or port changed then - * advertize the change to the keying daemon. - * This is an inbound SA, so just compare - * SRC ports. - */ - if (decap_data->proto == AF_INET && - (decap_data->saddr.a4 != x->props.saddr.a4 || - decap_data->sport != encap->encap_sport)) { - xfrm_address_t ipaddr; - - ipaddr.a4 = decap_data->saddr.a4; - km_new_mapping(x, &ipaddr, decap_data->sport); - - /* XXX: perhaps add an extra - * policy check here, to see - * if we should allow or - * reject a packet from a - * different source - * address/port. - */ - } - - /* - * 2) ignore UDP/TCP checksums in case - * of NAT-T in Transport Mode, or - * perform other post-processing fixes - * as per * draft-ietf-ipsec-udp-encaps-06, - * section 3.1.2 - */ - if (!x->props.mode) - skb->ip_summed = CHECKSUM_UNNECESSARY; - - break; - } - } - return 0; -} - static u32 esp4_get_max_size(struct xfrm_state *x, int mtu) { struct esp_data *esp = x->data; @@ -457,7 +415,6 @@ static struct xfrm_type esp_type = .destructor = esp_destroy, .get_max_size = esp4_get_max_size, .input = esp_input, - .post_input = esp_post_input, .output = esp_output }; @@ -469,15 +426,6 @@ static struct net_protocol esp4_protocol = { static int __init esp4_init(void) { - struct xfrm_decap_state decap; - - if (sizeof(struct esp_decap_data) > - sizeof(decap.decap_data)) { - extern void decap_data_too_small(void); - - decap_data_too_small(); - } - if (xfrm_register_type(&esp_type, AF_INET) < 0) { printk(KERN_INFO "ip esp init: can't add xfrm type\n"); return -EAGAIN; -- cgit v1.2.2