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Diffstat (limited to 'net/ipv4/esp4.c')
-rw-r--r--net/ipv4/esp4.c59
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
};