static int ipcomp6_output(struct sk_buff **pskb)
{
int err;
struct dst_entry *dst = (*pskb)->dst;
struct xfrm_state *x = dst->xfrm;
struct ipv6hdr *tmp_iph = NULL, *iph, *top_iph;
int hdr_len = 0;
struct ipv6_comp_hdr *ipch;
struct ipcomp_data *ipcd = x->data;
u8 *prevhdr;
u8 nexthdr = 0;
int plen, dlen;
u8 *start, *scratch = ipcd->scratch;
if ((*pskb)->ip_summed == CHECKSUM_HW) {
err = skb_checksum_help(pskb, 0);
if (err)
goto error_nolock;
}
spin_lock_bh(&x->lock);
err = xfrm_check_output(x, *pskb, AF_INET6);
if (err)
goto error;
if (x->props.mode) {
hdr_len = sizeof(struct ipv6hdr);
nexthdr = IPPROTO_IPV6;
iph = (*pskb)->nh.ipv6h;
top_iph = (struct ipv6hdr *)skb_push(*pskb, sizeof(struct ipv6hdr));
top_iph->version = 6;
top_iph->priority = iph->priority;
top_iph->flow_lbl[0] = iph->flow_lbl[0];
top_iph->flow_lbl[1] = iph->flow_lbl[1];
top_iph->flow_lbl[2] = iph->flow_lbl[2];
top_iph->nexthdr = IPPROTO_IPV6; /* initial */
top_iph->payload_len = htons((*pskb)->len - sizeof(struct ipv6hdr));
top_iph->hop_limit = iph->hop_limit;
memcpy(&top_iph->saddr, (struct in6_addr *)&x->props.saddr, sizeof(struct in6_addr));
memcpy(&top_iph->daddr, (struct in6_addr *)&x->id.daddr, sizeof(struct in6_addr));
(*pskb)->nh.raw = (*pskb)->data; /* == top_iph */
(*pskb)->h.raw = (*pskb)->nh.raw + hdr_len;
} else {
hdr_len = ip6_find_1stfragopt(*pskb, &prevhdr);
nexthdr = *prevhdr;
}
/* check whether datagram len is larger than threshold */
if (((*pskb)->len - hdr_len) < ipcd->threshold) {
goto out_ok;
}
if ((skb_is_nonlinear(*pskb) || skb_cloned(*pskb)) &&
skb_linearize(*pskb, GFP_ATOMIC) != 0) {
err = -ENOMEM;
goto error;
}
/* compression */
plen = (*pskb)->len - hdr_len;
dlen = IPCOMP_SCRATCH_SIZE;
start = (*pskb)->data + hdr_len;
err = crypto_comp_compress(ipcd->tfm, start, plen, scratch, &dlen);
if (err) {
goto error;
}
if ((dlen + sizeof(struct ipv6_comp_hdr)) >= plen) {
goto out_ok;
}
memcpy(start, scratch, dlen);
pskb_trim(*pskb, hdr_len+dlen);
/* insert ipcomp header and replace datagram */
tmp_iph = kmalloc(hdr_len, GFP_ATOMIC);
if (!tmp_iph) {
err = -ENOMEM;
goto error;
}
memcpy(tmp_iph, (*pskb)->nh.raw, hdr_len);
top_iph = (struct ipv6hdr*)skb_push(*pskb, sizeof(struct ipv6_comp_hdr));
memcpy(top_iph, tmp_iph, hdr_len);
kfree(tmp_iph);
if (x->props.mode && (x->props.flags & XFRM_STATE_NOECN))
IP6_ECN_clear(top_iph);
top_iph->payload_len = htons((*pskb)->len - sizeof(struct ipv6hdr));
(*pskb)->nh.raw = (*pskb)->data; /* top_iph */
ip6_find_1stfragopt(*pskb, &prevhdr);
*prevhdr = IPPROTO_COMP;
ipch = (struct ipv6_comp_hdr *)((unsigned char *)top_iph + hdr_len);
ipch->nexthdr = nexthdr;
ipch->flags = 0;
ipch->cpi = htons((u16 )ntohl(x->id.spi));
(*pskb)->h.raw = (unsigned char*)ipch;
out_ok:
x->curlft.bytes += (*pskb)->len;
x->curlft.packets++;
spin_unlock_bh(&x->lock);
if (((*pskb)->dst = dst_pop(dst)) == NULL) {
err = -EHOSTUNREACH;
goto error_nolock;
}
err = NET_XMIT_BYPASS;
out_exit:
return err;
error:
spin_unlock_bh(&x->lock);
error_nolock:
kfree_skb(*pskb);
goto out_exit;
}
int esp6_output(struct sk_buff *skb)
{
int err;
int hdr_len = 0;
struct dst_entry *dst = skb->dst;
struct xfrm_state *x = dst->xfrm;
struct ipv6hdr *iph = NULL, *top_iph;
struct ipv6_esp_hdr *esph;
struct crypto_tfm *tfm;
struct esp_data *esp;
struct sk_buff *trailer;
int blksize;
int clen;
int alen;
int nfrags;
u8 *prevhdr;
u8 nexthdr = 0;
/* First, if the skb is not checksummed, complete checksum. */
if (skb->ip_summed == CHECKSUM_HW && skb_checksum_help(skb) == NULL) {
err = -EINVAL;
goto error_nolock;
}
spin_lock_bh(&x->lock);
err = xfrm_check_output(x, skb, AF_INET6);
if (err)
goto error;
err = -ENOMEM;
/* Strip IP header in transport mode. Save it. */
if (!x->props.mode) {
hdr_len = ip6_find_1stfragopt(skb, &prevhdr);
nexthdr = *prevhdr;
*prevhdr = IPPROTO_ESP;
iph = kmalloc(hdr_len, GFP_ATOMIC);
if (!iph) {
err = -ENOMEM;
goto error;
}
memcpy(iph, skb->nh.raw, hdr_len);
__skb_pull(skb, hdr_len);
}
/* Now skb is pure payload to encrypt */
/* Round to block size */
clen = skb->len;
esp = x->data;
alen = esp->auth.icv_trunc_len;
tfm = esp->conf.tfm;
blksize = (crypto_tfm_alg_blocksize(tfm) + 3) & ~3;
clen = (clen + 2 + blksize-1)&~(blksize-1);
if (esp->conf.padlen)
clen = (clen + esp->conf.padlen-1)&~(esp->conf.padlen-1);
if ((nfrags = skb_cow_data(skb, clen-skb->len+alen, &trailer)) < 0) {
if (!x->props.mode && iph) kfree(iph);
goto error;
}
/* Fill padding... */
do {
int i;
for (i=0; i<clen-skb->len - 2; i++)
*(u8*)(trailer->tail + i) = i+1;
} while (0);
*(u8*)(trailer->tail + clen-skb->len - 2) = (clen - skb->len)-2;
pskb_put(skb, trailer, clen - skb->len);
if (x->props.mode) {
iph = skb->nh.ipv6h;
top_iph = (struct ipv6hdr*)skb_push(skb, x->props.header_len);
esph = (struct ipv6_esp_hdr*)(top_iph+1);
*(u8*)(trailer->tail - 1) = IPPROTO_IPV6;
top_iph->version = 6;
top_iph->priority = iph->priority;
top_iph->flow_lbl[0] = iph->flow_lbl[0];
top_iph->flow_lbl[1] = iph->flow_lbl[1];
top_iph->flow_lbl[2] = iph->flow_lbl[2];
if (x->props.flags & XFRM_STATE_NOECN)
IP6_ECN_clear(top_iph);
top_iph->nexthdr = IPPROTO_ESP;
top_iph->payload_len = htons(skb->len + alen - sizeof(struct ipv6hdr));
top_iph->hop_limit = iph->hop_limit;
ipv6_addr_copy(&top_iph->saddr,
(struct in6_addr *)&x->props.saddr);
ipv6_addr_copy(&top_iph->daddr,
(struct in6_addr *)&x->id.daddr);
} else {
esph = (struct ipv6_esp_hdr*)skb_push(skb, x->props.header_len);
skb->h.raw = (unsigned char*)esph;
top_iph = (struct ipv6hdr*)skb_push(skb, hdr_len);
memcpy(top_iph, iph, hdr_len);
kfree(iph);
top_iph->payload_len = htons(skb->len + alen - sizeof(struct ipv6hdr));
*(u8*)(trailer->tail - 1) = nexthdr;
}
esph->spi = x->id.spi;
esph->seq_no = htonl(++x->replay.oseq);
if (esp->conf.ivlen)
crypto_cipher_set_iv(tfm, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm));
do {
struct scatterlist sgbuf[nfrags>MAX_SG_ONSTACK ? 0 : nfrags];
struct scatterlist *sg = sgbuf;
if (unlikely(nfrags > MAX_SG_ONSTACK)) {
sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC);
if (!sg)
goto error;
}
skb_to_sgvec(skb, sg, esph->enc_data+esp->conf.ivlen-skb->data, clen);
crypto_cipher_encrypt(tfm, sg, sg, clen);
if (unlikely(sg != sgbuf))
kfree(sg);
} while (0);
if (esp->conf.ivlen) {
memcpy(esph->enc_data, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm));
crypto_cipher_get_iv(tfm, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm));
}
if (esp->auth.icv_full_len) {
esp->auth.icv(esp, skb, (u8*)esph-skb->data,
sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen+clen, trailer->tail);
pskb_put(skb, trailer, alen);
}
skb->nh.raw = skb->data;
x->curlft.bytes += skb->len;
x->curlft.packets++;
spin_unlock_bh(&x->lock);
if ((skb->dst = dst_pop(dst)) == NULL) {
err = -EHOSTUNREACH;
goto error_nolock;
}
return NET_XMIT_BYPASS;
error:
spin_unlock_bh(&x->lock);
error_nolock:
kfree_skb(skb);
return err;
}
