diff options
Diffstat (limited to 'net/ipv4/esp4.c')
| -rw-r--r-- | net/ipv4/esp4.c | 59 |
1 files changed, 35 insertions, 24 deletions
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index 31041127eeb..47c95e8ef04 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -21,13 +21,14 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb) struct blkcipher_desc desc; struct esp_data *esp; struct sk_buff *trailer; + u8 *tail; int blksize; int clen; int alen; int nfrags; /* Strip IP+ESP header. */ - __skb_pull(skb, skb->h.raw - skb->data); + __skb_pull(skb, skb_transport_offset(skb)); /* Now skb is pure payload to encrypt */ err = -ENOMEM; @@ -49,19 +50,21 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb) goto error; /* Fill padding... */ + tail = skb_tail_pointer(trailer); do { int i; for (i=0; i<clen-skb->len - 2; i++) - *(u8*)(trailer->tail + i) = i+1; + tail[i] = i + 1; } while (0); - *(u8*)(trailer->tail + clen-skb->len - 2) = (clen - skb->len)-2; + tail[clen - skb->len - 2] = (clen - skb->len) - 2; pskb_put(skb, trailer, clen - skb->len); - __skb_push(skb, skb->data - skb->nh.raw); - top_iph = skb->nh.iph; - esph = (struct ip_esp_hdr *)(skb->nh.raw + top_iph->ihl*4); + __skb_push(skb, skb->data - skb_network_header(skb)); + top_iph = ip_hdr(skb); + esph = (struct ip_esp_hdr *)(skb_network_header(skb) + + top_iph->ihl * 4); top_iph->tot_len = htons(skb->len + alen); - *(u8*)(trailer->tail - 1) = top_iph->protocol; + *(skb_tail_pointer(trailer) - 1) = top_iph->protocol; /* this is non-NULL only with UDP Encapsulation */ if (x->encap) { @@ -217,12 +220,12 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb) /* ... check padding bits here. Silly. :-) */ - iph = skb->nh.iph; + iph = ip_hdr(skb); ihl = iph->ihl * 4; if (x->encap) { struct xfrm_encap_tmpl *encap = x->encap; - struct udphdr *uh = (void *)(skb->nh.raw + ihl); + struct udphdr *uh = (void *)(skb_network_header(skb) + ihl); /* * 1) if the NAT-T peer's IP or port changed then @@ -260,7 +263,8 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb) iph->protocol = nexthdr[1]; pskb_trim(skb, skb->len - alen - padlen - 2); - skb->h.raw = __skb_pull(skb, sizeof(*esph) + esp->conf.ivlen) - ihl; + __skb_pull(skb, sizeof(*esph) + esp->conf.ivlen); + skb_set_transport_header(skb, -ihl); return 0; @@ -268,32 +272,33 @@ out: return -EINVAL; } -static u32 esp4_get_max_size(struct xfrm_state *x, int mtu) +static u32 esp4_get_mtu(struct xfrm_state *x, int mtu) { struct esp_data *esp = x->data; u32 blksize = ALIGN(crypto_blkcipher_blocksize(esp->conf.tfm), 4); - int enclen = 0; + u32 align = max_t(u32, blksize, esp->conf.padlen); + u32 rem; + + mtu -= x->props.header_len + esp->auth.icv_trunc_len; + rem = mtu & (align - 1); + mtu &= ~(align - 1); switch (x->props.mode) { case XFRM_MODE_TUNNEL: - mtu = ALIGN(mtu +2, blksize); break; default: case XFRM_MODE_TRANSPORT: /* The worst case */ - mtu = ALIGN(mtu + 2, 4) + blksize - 4; + mtu -= blksize - 4; + mtu += min_t(u32, blksize - 4, rem); break; case XFRM_MODE_BEET: /* The worst case. */ - enclen = IPV4_BEET_PHMAXLEN; - mtu = ALIGN(mtu + enclen + 2, blksize); + mtu += min_t(u32, IPV4_BEET_PHMAXLEN, rem); break; } - if (esp->conf.padlen) - mtu = ALIGN(mtu, esp->conf.padlen); - - return mtu + x->props.header_len + esp->auth.icv_trunc_len - enclen; + return mtu - 2; } static void esp4_err(struct sk_buff *skb, u32 info) @@ -302,8 +307,8 @@ static void esp4_err(struct sk_buff *skb, u32 info) struct ip_esp_hdr *esph = (struct ip_esp_hdr*)(skb->data+(iph->ihl<<2)); struct xfrm_state *x; - if (skb->h.icmph->type != ICMP_DEST_UNREACH || - skb->h.icmph->code != ICMP_FRAG_NEEDED) + if (icmp_hdr(skb)->type != ICMP_DEST_UNREACH || + icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) return; x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, esph->spi, IPPROTO_ESP, AF_INET); @@ -336,6 +341,7 @@ static int esp_init_state(struct xfrm_state *x) { struct esp_data *esp = NULL; struct crypto_blkcipher *tfm; + u32 align; /* null auth and encryption can have zero length keys */ if (x->aalg) { @@ -402,6 +408,8 @@ static int esp_init_state(struct xfrm_state *x) x->props.header_len = sizeof(struct ip_esp_hdr) + esp->conf.ivlen; if (x->props.mode == XFRM_MODE_TUNNEL) x->props.header_len += sizeof(struct iphdr); + else if (x->props.mode == XFRM_MODE_BEET) + x->props.header_len += IPV4_BEET_PHMAXLEN; if (x->encap) { struct xfrm_encap_tmpl *encap = x->encap; @@ -417,7 +425,10 @@ static int esp_init_state(struct xfrm_state *x) } } x->data = esp; - x->props.trailer_len = esp4_get_max_size(x, 0) - x->props.header_len; + align = ALIGN(crypto_blkcipher_blocksize(esp->conf.tfm), 4); + if (esp->conf.padlen) + align = max_t(u32, align, esp->conf.padlen); + x->props.trailer_len = align + 1 + esp->auth.icv_trunc_len; return 0; error: @@ -434,7 +445,7 @@ static struct xfrm_type esp_type = .proto = IPPROTO_ESP, .init_state = esp_init_state, .destructor = esp_destroy, - .get_max_size = esp4_get_max_size, + .get_mtu = esp4_get_mtu, .input = esp_input, .output = esp_output }; |