int xfrm6_rcv_spi(struct sk_buff *skb, __be32 spi)
{
int err;
__be32 seq;
struct xfrm_state *xfrm_vec[XFRM_MAX_DEPTH];
struct xfrm_state *x;
int xfrm_nr = 0;
int decaps = 0;
int nexthdr;
unsigned int nhoff;
nhoff = IP6CB(skb)->nhoff;
nexthdr = skb_network_header(skb)[nhoff];
seq = 0;
if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0)
goto drop;
do {
struct ipv6hdr *iph = skb->nh.ipv6h;
if (xfrm_nr == XFRM_MAX_DEPTH)
goto drop;
x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi,
nexthdr != IPPROTO_IPIP ? nexthdr : IPPROTO_IPV6, AF_INET6);
if (x == NULL)
goto drop;
spin_lock(&x->lock);
if (unlikely(x->km.state != XFRM_STATE_VALID))
goto drop_unlock;
if (x->props.replay_window && xfrm_replay_check(x, seq))
goto drop_unlock;
if (xfrm_state_check_expire(x))
goto drop_unlock;
nexthdr = x->type->input(x, skb);
if (nexthdr <= 0)
goto drop_unlock;
skb_network_header(skb)[nhoff] = nexthdr;
if (x->props.replay_window)
xfrm_replay_advance(x, seq);
x->curlft.bytes += skb->len;
x->curlft.packets++;
spin_unlock(&x->lock);
xfrm_vec[xfrm_nr++] = x;
if (x->mode->input(x, skb))
goto drop;
if (x->props.mode == XFRM_MODE_TUNNEL) { /* XXX */
decaps = 1;
break;
}
if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) < 0)
goto drop;
} while (!err);
/* Allocate new secpath or COW existing one. */
if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
struct sec_path *sp;
sp = secpath_dup(skb->sp);
if (!sp)
goto drop;
if (skb->sp)
secpath_put(skb->sp);
skb->sp = sp;
}
if (xfrm_nr + skb->sp->len > XFRM_MAX_DEPTH)
goto drop;
memcpy(skb->sp->xvec + skb->sp->len, xfrm_vec,
xfrm_nr * sizeof(xfrm_vec[0]));
skb->sp->len += xfrm_nr;
skb->ip_summed = CHECKSUM_NONE;
nf_reset(skb);
if (decaps) {
dst_release(skb->dst);
skb->dst = NULL;
netif_rx(skb);
return -1;
} else {
#ifdef CONFIG_NETFILTER
skb->nh.ipv6h->payload_len = htons(skb->len);
__skb_push(skb, skb->data - skb_network_header(skb));
NF_HOOK(PF_INET6, NF_IP6_PRE_ROUTING, skb, skb->dev, NULL,
ip6_rcv_finish);
return -1;
#else
return 1;
#endif
}
drop_unlock:
spin_unlock(&x->lock);
xfrm_state_put(x);
drop:
while (--xfrm_nr >= 0)
xfrm_state_put(xfrm_vec[xfrm_nr]);
kfree_skb(skb);
return -1;
}
int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
{
int err;
u32 spi, seq;
struct sec_decap_state xfrm_vec[XFRM_MAX_DEPTH];
struct xfrm_state *x;
int xfrm_nr = 0;
int decaps = 0;
if ((err = xfrm4_parse_spi(skb, skb->nh.iph->protocol, &spi, &seq)) != 0)
goto drop;
do {
struct iphdr *iph = skb->nh.iph;
if (xfrm_nr == XFRM_MAX_DEPTH)
goto drop;
x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi, iph->protocol, AF_INET);
if (x == NULL)
goto drop;
spin_lock(&x->lock);
if (unlikely(x->km.state != XFRM_STATE_VALID))
goto drop_unlock;
if (x->props.replay_window && xfrm_replay_check(x, seq))
goto drop_unlock;
if (xfrm_state_check_expire(x))
goto drop_unlock;
xfrm_vec[xfrm_nr].decap.decap_type = encap_type;
if (x->type->input(x, &(xfrm_vec[xfrm_nr].decap), skb))
goto drop_unlock;
/* only the first xfrm gets the encap type */
encap_type = 0;
if (x->props.replay_window)
xfrm_replay_advance(x, seq);
x->curlft.bytes += skb->len;
x->curlft.packets++;
spin_unlock(&x->lock);
xfrm_vec[xfrm_nr++].xvec = x;
iph = skb->nh.iph;
if (x->props.mode) {
if (iph->protocol != IPPROTO_IPIP)
goto drop;
if (!pskb_may_pull(skb, sizeof(struct iphdr)))
goto drop;
if (skb_cloned(skb) &&
pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
goto drop;
if (!(x->props.flags & XFRM_STATE_NOECN))
ipip_ecn_decapsulate(skb);
skb->mac.raw = memmove(skb->data - skb->mac_len,
skb->mac.raw, skb->mac_len);
skb->nh.raw = skb->data;
memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
decaps = 1;
break;
}
if ((err = xfrm_parse_spi(skb, skb->nh.iph->protocol, &spi, &seq)) < 0)
goto drop;
} while (!err);
/* Allocate new secpath or COW existing one. */
if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
struct sec_path *sp;
sp = secpath_dup(skb->sp);
if (!sp)
goto drop;
if (skb->sp)
secpath_put(skb->sp);
skb->sp = sp;
}
if (xfrm_nr + skb->sp->len > XFRM_MAX_DEPTH)
goto drop;
memcpy(skb->sp->x+skb->sp->len, xfrm_vec, xfrm_nr*sizeof(struct sec_decap_state));
skb->sp->len += xfrm_nr;
if (decaps) {
if (!(skb->dev->flags&IFF_LOOPBACK)) {
dst_release(skb->dst);
skb->dst = NULL;
}
netif_rx(skb);
return 0;
} else {
return -skb->nh.iph->protocol;
}
drop_unlock:
spin_unlock(&x->lock);
xfrm_state_put(x);
drop:
while (--xfrm_nr >= 0)
xfrm_state_put(xfrm_vec[xfrm_nr].xvec);
kfree_skb(skb);
return 0;
}
static int esp6_input(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb)
{
struct ipv6hdr *iph;
struct ipv6_esp_hdr *esph;
struct esp_data *esp = x->data;
struct sk_buff *trailer;
int blksize = ALIGN(crypto_tfm_alg_blocksize(esp->conf.tfm), 4);
int alen = esp->auth.icv_trunc_len;
int elen = skb->len - sizeof(struct ipv6_esp_hdr) - esp->conf.ivlen - alen;
int hdr_len = skb->h.raw - skb->nh.raw;
int nfrags;
unsigned char *tmp_hdr = NULL;
int ret = 0;
if (!pskb_may_pull(skb, sizeof(struct ipv6_esp_hdr))) {
ret = -EINVAL;
goto out_nofree;
}
esph = (struct ipv6_esp_hdr*)skb->data;
if (elen <= 0 || (elen & (blksize-1))) {
ret = -EINVAL;
goto out_nofree;
}
tmp_hdr = kmalloc(hdr_len, GFP_ATOMIC);
if (!tmp_hdr) {
ret = -ENOMEM;
goto out_nofree;
}
memcpy(tmp_hdr, skb->nh.raw, hdr_len);
/* If integrity check is required, do this. */
if (esp->auth.icv_full_len) {
u8 sum[esp->auth.icv_full_len];
u8 sum1[alen];
if (x->props.replay_window && xfrm_replay_check(x, esph->seq_no)) {
ret = -EINVAL;
goto out;
}
esp->auth.icv(esp, skb, 0, skb->len-alen, sum);
if (skb_copy_bits(skb, skb->len-alen, sum1, alen))
BUG();
if (unlikely(memcmp(sum, sum1, alen))) {
x->stats.integrity_failed++;
ret = -EINVAL;
goto out;
}
if (x->props.replay_window)
xfrm_replay_advance(x, esph->seq_no);
}
if ((nfrags = skb_cow_data(skb, 0, &trailer)) < 0) {
ret = -EINVAL;
goto out;
}
skb->ip_summed = CHECKSUM_NONE;
iph = skb->nh.ipv6h;
/* Get ivec. This can be wrong, check against another impls. */
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 padlen;
if (unlikely(nfrags > ESP_NUM_FAST_SG)) {
sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC);
if (!sg) {
ret = -ENOMEM;
goto out;
}
}
skb_to_sgvec(skb, sg, sizeof(struct ipv6_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();
padlen = nexthdr[0];
if (padlen+2 >= elen) {
LIMIT_NETDEBUG(KERN_WARNING "ipsec esp packet is garbage padlen=%d, elen=%d\n", padlen+2, elen);
ret = -EINVAL;
goto out;
}
/* ... check padding bits here. Silly. :-) */
pskb_trim(skb, skb->len - alen - padlen - 2);
skb->h.raw = skb_pull(skb, sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen);
skb->nh.raw += sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen;
memcpy(skb->nh.raw, tmp_hdr, hdr_len);
skb->nh.ipv6h->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
ret = nexthdr[1];
}
out:
kfree(tmp_hdr);
out_nofree:
return ret;
}
int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
{
int err;
__be32 spi, seq;
struct xfrm_state *xfrm_vec[XFRM_MAX_DEPTH];
struct xfrm_state *x;
int xfrm_nr = 0;
int decaps = 0;
if ((err = xfrm4_parse_spi(skb, skb->nh.iph->protocol, &spi, &seq)) != 0)
goto drop;
do {
struct iphdr *iph = skb->nh.iph;
if (xfrm_nr == XFRM_MAX_DEPTH)
goto drop;
x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi, iph->protocol, AF_INET);
if (x == NULL)
goto drop;
spin_lock(&x->lock);
if (unlikely(x->km.state != XFRM_STATE_VALID))
goto drop_unlock;
if ((x->encap ? x->encap->encap_type : 0) != encap_type)
goto drop_unlock;
if (x->props.replay_window && xfrm_replay_check(x, seq))
goto drop_unlock;
if (xfrm_state_check_expire(x))
goto drop_unlock;
if (x->type->input(x, skb))
goto drop_unlock;
/* only the first xfrm gets the encap type */
encap_type = 0;
if (x->props.replay_window)
xfrm_replay_advance(x, seq);
x->curlft.bytes += skb->len;
x->curlft.packets++;
spin_unlock(&x->lock);
xfrm_vec[xfrm_nr++] = x;
if (x->mode->input(x, skb))
goto drop;
if (x->props.mode == XFRM_MODE_TUNNEL) {
decaps = 1;
break;
}
if ((err = xfrm_parse_spi(skb, skb->nh.iph->protocol, &spi, &seq)) < 0)
goto drop;
} while (!err);
/* Allocate new secpath or COW existing one. */
if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
struct sec_path *sp;
sp = secpath_dup(skb->sp);
if (!sp)
goto drop;
if (skb->sp)
secpath_put(skb->sp);
skb->sp = sp;
}
if (xfrm_nr + skb->sp->len > XFRM_MAX_DEPTH)
goto drop;
memcpy(skb->sp->xvec + skb->sp->len, xfrm_vec,
xfrm_nr * sizeof(xfrm_vec[0]));
skb->sp->len += xfrm_nr;
nf_reset(skb);
if (decaps) {
if (!(skb->dev->flags&IFF_LOOPBACK)) {
dst_release(skb->dst);
skb->dst = NULL;
}
netif_rx(skb);
return 0;
} else {
#ifdef CONFIG_NETFILTER
__skb_push(skb, skb->data - skb->nh.raw);
skb->nh.iph->tot_len = htons(skb->len);
ip_send_check(skb->nh.iph);
NF_HOOK(PF_INET, NF_IP_PRE_ROUTING, skb, skb->dev, NULL,
xfrm4_rcv_encap_finish);
return 0;
#else
return -skb->nh.iph->protocol;
#endif
}
drop_unlock:
spin_unlock(&x->lock);
xfrm_state_put(x);
drop:
while (--xfrm_nr >= 0)
xfrm_state_put(xfrm_vec[xfrm_nr]);
kfree_skb(skb);
return 0;
}
int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
{
struct net *net = dev_net(skb->dev);
int err;
__be32 seq;
struct xfrm_state *x;
xfrm_address_t *daddr;
struct xfrm_mode *inner_mode;
unsigned int family;
int decaps = 0;
int async = 0;
/* A negative encap_type indicates async resumption. */
if (encap_type < 0) {
async = 1;
x = xfrm_input_state(skb);
seq = XFRM_SKB_CB(skb)->seq.input;
goto resume;
}
/* Allocate new secpath or COW existing one. */
if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
struct sec_path *sp;
sp = secpath_dup(skb->sp);
if (!sp) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
goto drop;
}
if (skb->sp)
secpath_put(skb->sp);
skb->sp = sp;
}
daddr = (xfrm_address_t *)(skb_network_header(skb) +
XFRM_SPI_SKB_CB(skb)->daddroff);
family = XFRM_SPI_SKB_CB(skb)->family;
seq = 0;
if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
goto drop;
}
do {
if (skb->sp->len == XFRM_MAX_DEPTH) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
goto drop;
}
x = xfrm_state_lookup_with_mark(net, skb->mark, daddr, spi, nexthdr, family);
if (x == NULL) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
xfrm_audit_state_notfound(skb, family, spi, seq);
goto drop;
}
skb->sp->xvec[skb->sp->len++] = x;
spin_lock(&x->lock);
if (unlikely(x->km.state != XFRM_STATE_VALID)) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEINVALID);
goto drop_unlock;
}
if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
goto drop_unlock;
}
if (x->props.replay_window && xfrm_replay_check(x, skb, seq)) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
goto drop_unlock;
}
if (xfrm_state_check_expire(x)) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
goto drop_unlock;
}
spin_unlock(&x->lock);
XFRM_SKB_CB(skb)->seq.input = seq;
nexthdr = x->type->input(x, skb);
if (nexthdr == -EINPROGRESS)
return 0;
resume:
spin_lock(&x->lock);
if (nexthdr <= 0) {
if (nexthdr == -EBADMSG) {
xfrm_audit_state_icvfail(x, skb,
x->type->proto);
x->stats.integrity_failed++;
}
XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
goto drop_unlock;
}
/* only the first xfrm gets the encap type */
encap_type = 0;
if (x->props.replay_window)
xfrm_replay_advance(x, seq);
x->curlft.bytes += skb->len;
x->curlft.packets++;
spin_unlock(&x->lock);
XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
inner_mode = x->inner_mode;
if (x->sel.family == AF_UNSPEC) {
inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
if (inner_mode == NULL)
goto drop;
}
if (inner_mode->input(x, skb)) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
goto drop;
}
if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) {
decaps = 1;
break;
}
/*
* We need the inner address. However, we only get here for
* transport mode so the outer address is identical.
*/
daddr = &x->id.daddr;
family = x->outer_mode->afinfo->family;
err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
if (err < 0) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
goto drop;
}
} while (!err);
nf_reset(skb);
if (decaps) {
skb_dst_drop(skb);
netif_rx(skb);
return 0;
} else {
return x->inner_mode->afinfo->transport_finish(skb, async);
}
drop_unlock:
spin_unlock(&x->lock);
drop:
kfree_skb(skb);
return 0;
}
int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
{
int err;
u32 spi, seq;
struct sec_decap_state xfrm_vec[XFRM_MAX_DEPTH];
struct xfrm_state *x;
int xfrm_nr = 0;
int decaps = 0;
int offset = 0;
if ((err = xfrm4_parse_spi(skb, skb->nh.iph->protocol, &spi, &seq)) != 0)
goto drop;
do {
struct iphdr *iph = skb->nh.iph;
if (xfrm_nr == XFRM_MAX_DEPTH)
goto drop;
x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi, iph->protocol, AF_INET);
if (x == NULL)
goto drop;
spin_lock(&x->lock);
if (unlikely(x->km.state != XFRM_STATE_VALID))
goto drop_unlock;
#if defined(CONFIG_CAVIUM_OCTEON_IPSEC) && defined(CONFIG_NET_KEY)
/*
* If Octeon IPSEC Acceleration module has been loaded
* call it, otherwise, follow the software path
*/
if(cavium_ipsec_process)
{
if (xfrm_state_check_expire(x))
goto drop_unlock;
xfrm_vec[xfrm_nr].decap.decap_type = encap_type;
switch (skb->nh.iph->protocol) {
case IPPROTO_AH:
offset = offsetof(struct ip_auth_hdr, nexthdr);
break;
case IPPROTO_ESP:
offset = offsetof(struct ip_esp_hdr, spi);
break;
default:
return -skb->nh.iph->protocol;
}
offset += (uint64_t)skb->data - (uint64_t)skb->nh.iph;
/*
* skb->data points to the start of the esp/ah header
* but we require skb->data to point to the start of ip header.
*/
skb_push(skb, (unsigned int)((uint64_t)skb->data - (uint64_t)skb->nh.iph));
if (skb_is_nonlinear(skb) &&
skb_linearize(skb, GFP_ATOMIC) != 0) {
err = -ENOMEM;
goto drop_unlock;
}
if (skb_cloned(skb) &&
pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
{
err = -ENOMEM;
goto drop_unlock;
}
err = cavium_ipsec_process(x->sa_handle, skb, offset, 0 /*DECRYPT*/);
if(err)
goto drop_unlock;
/* only the first xfrm gets the encap type */
encap_type = 0;
x->curlft.bytes += skb->len;
x->curlft.packets++;
spin_unlock(&x->lock);
xfrm_vec[xfrm_nr++].xvec = x;
iph = skb->nh.iph;
if (x->props.mode) {
#if 0
if (skb_cloned(skb) &&
pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
goto drop;
/*
* TODO, support ECN and dscp decapsulation
*/
if (x->props.flags & XFRM_STATE_DECAP_DSCP)
ipv4_copy_dscp(iph, skb->h.ipiph);
if (!(x->props.flags & XFRM_STATE_NOECN))
ipip_ecn_decapsulate(skb);
#endif
skb->nh.raw = skb->data;
memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
decaps = 1;
break;
}
} else { /* if (cavium_ipsec_process == NULL) */
if (x->props.replay_window && xfrm_replay_check(x, seq))
goto drop_unlock;
if (xfrm_state_check_expire(x))
goto drop_unlock;
xfrm_vec[xfrm_nr].decap.decap_type = encap_type;
if (x->type->input(x, &(xfrm_vec[xfrm_nr].decap), skb))
goto drop_unlock;
/* only the first xfrm gets the encap type */
encap_type = 0;
if (x->props.replay_window)
xfrm_replay_advance(x, seq);
x->curlft.bytes += skb->len;
x->curlft.packets++;
spin_unlock(&x->lock);
xfrm_vec[xfrm_nr++].xvec = x;
iph = skb->nh.iph;
if (x->props.mode) {
if (iph->protocol != IPPROTO_IPIP)
goto drop;
if (!pskb_may_pull(skb, sizeof(struct iphdr)))
goto drop;
if (skb_cloned(skb) &&
pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
goto drop;
if (x->props.flags & XFRM_STATE_DECAP_DSCP)
ipv4_copy_dscp(iph, skb->h.ipiph);
if (!(x->props.flags & XFRM_STATE_NOECN))
ipip_ecn_decapsulate(skb);
skb->mac.raw = memmove(skb->data - skb->mac_len,
skb->mac.raw, skb->mac_len);
skb->nh.raw = skb->data;
memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
decaps = 1;
break;
}
} /* if (cavium_ipsec_process) */
#else
if (x->props.replay_window && xfrm_replay_check(x, seq))
goto drop_unlock;
if (xfrm_state_check_expire(x))
goto drop_unlock;
xfrm_vec[xfrm_nr].decap.decap_type = encap_type;
if (x->type->input(x, &(xfrm_vec[xfrm_nr].decap), skb))
goto drop_unlock;
/* only the first xfrm gets the encap type */
encap_type = 0;
if (x->props.replay_window)
xfrm_replay_advance(x, seq);
x->curlft.bytes += skb->len;
x->curlft.packets++;
spin_unlock(&x->lock);
xfrm_vec[xfrm_nr++].xvec = x;
iph = skb->nh.iph;
if (x->props.mode) {
if (iph->protocol != IPPROTO_IPIP)
goto drop;
if (!pskb_may_pull(skb, sizeof(struct iphdr)))
goto drop;
if (skb_cloned(skb) &&
pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
goto drop;
if (x->props.flags & XFRM_STATE_DECAP_DSCP)
ipv4_copy_dscp(iph, skb->h.ipiph);
if (!(x->props.flags & XFRM_STATE_NOECN))
ipip_ecn_decapsulate(skb);
skb->mac.raw = memmove(skb->data - skb->mac_len,
skb->mac.raw, skb->mac_len);
skb->nh.raw = skb->data;
memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
decaps = 1;
break;
}
#endif
if ((err = xfrm_parse_spi(skb, skb->nh.iph->protocol, &spi, &seq)) < 0)
goto drop;
} while (!err);
/*
* Note: detecting truncated vs. non-truncated authentication data is very
* expensive, so we only support truncated data, which is the recommended
* and common case.
*/
static int esp_input(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb)
{
struct iphdr *iph;
struct ip_esp_hdr *esph;
struct esp_data *esp = x->data;
struct sk_buff *trailer;
int blksize = ALIGN(crypto_tfm_alg_blocksize(esp->conf.tfm), 4);
int alen = esp->auth.icv_trunc_len;
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;
esph = (struct ip_esp_hdr*)skb->data;
if (elen <= 0 || (elen & (blksize-1)))
goto out;
/* If integrity check is required, do this. */
if (esp->auth.icv_full_len) {
u8 sum[esp->auth.icv_full_len];
u8 sum1[alen];
if (x->props.replay_window && xfrm_replay_check(x, esph->seq_no))
goto out;
esp->auth.icv(esp, skb, 0, skb->len-alen, sum);
if (skb_copy_bits(skb, skb->len-alen, sum1, alen))
BUG();
if (unlikely(memcmp(sum, sum1, alen))) {
x->stats.integrity_failed++;
goto out;
}
if (x->props.replay_window)
xfrm_replay_advance(x, esph->seq_no);
}
if ((nfrags = skb_cow_data(skb, 0, &trailer)) < 0)
goto out;
skb->ip_summed = CHECKSUM_NONE;
iph = skb->nh.iph;
/* Get ivec. This can be wrong, check against another impls. */
if (esp->conf.ivlen)
crypto_cipher_set_iv(esp->conf.tfm, esph->enc_data, crypto_tfm_alg_ivsize(esp->conf.tfm));
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 (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2))
BUG();
padlen = nexthdr[0];
if (padlen+2 >= elen)
goto out;
/* ... check padding bits here. Silly. :-) */
if (x->encap) {
struct xfrm_encap_tmpl *encap = x->encap;
struct udphdr *uh;
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];
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:
return -EINVAL;
}
static int ah_input(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb)
{
int ah_hlen;
struct iphdr *iph;
struct ip_auth_hdr *ah;
struct ah_data *ahp;
char work_buf[60];
if (!pskb_may_pull(skb, sizeof(struct ip_auth_hdr)))
goto out;
ah = (struct ip_auth_hdr*)skb->data;
if (x->props.replay_window && xfrm_replay_check(x, ah->seq_no))
goto out;
ahp = x->data;
ah_hlen = (ah->hdrlen + 2) << 2;
if (ah_hlen != XFRM_ALIGN8(sizeof(struct ip_auth_hdr) + ahp->icv_full_len) &&
ah_hlen != XFRM_ALIGN8(sizeof(struct ip_auth_hdr) + ahp->icv_trunc_len))
goto out;
if (!pskb_may_pull(skb, ah_hlen))
goto out;
/* We are going to _remove_ AH header to keep sockets happy,
* so... Later this can change. */
if (skb_cloned(skb) &&
pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
goto out;
skb->ip_summed = CHECKSUM_NONE;
ah = (struct ip_auth_hdr*)skb->data;
iph = skb->nh.iph;
memcpy(work_buf, iph, iph->ihl*4);
iph->ttl = 0;
iph->tos = 0;
iph->frag_off = 0;
iph->check = 0;
if (iph->ihl != 5) {
u32 dummy;
if (ip_clear_mutable_options(iph, &dummy))
goto out;
}
{
u8 auth_data[MAX_AH_AUTH_LEN];
memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
skb_push(skb, skb->data - skb->nh.raw);
ahp->icv(ahp, skb, ah->auth_data);
if (memcmp(ah->auth_data, auth_data, ahp->icv_trunc_len)) {
x->stats.integrity_failed++;
goto out;
}
}
if (x->props.replay_window)
xfrm_replay_advance(x, ah->seq_no);
((struct iphdr*)work_buf)->protocol = ah->nexthdr;
skb->nh.raw = skb_pull(skb, ah_hlen);
memcpy(skb->nh.raw, work_buf, iph->ihl*4);
skb->nh.iph->tot_len = htons(skb->len);
skb_pull(skb, skb->nh.iph->ihl*4);
skb->h.raw = skb->data;
return 0;
out:
return -EINVAL;
}
int xfrm6_input_resume(struct sk_buff *skb, int nexthdr)
{
int err;
int spi;
u32 seq;
struct xfrm_state *x;
int decaps = 0;
unsigned int nhoff;
nhoff = IP6CB(skb)->nhoff;
x = skb->sp->xvec[skb->sp->len - 1];
seq = XFRM_SKB_CB(skb)->seq;
spin_lock(&x->lock);
goto resume;
do {
struct ipv6hdr *iph = skb->nh.ipv6h;
if (skb->sp->len == XFRM_MAX_DEPTH)
goto drop;
x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi, nexthdr, AF_INET6);
if (x == NULL) {
xfrm_naudit_state_notfound(skb, AF_INET6, spi, seq);
goto drop;
}
skb->sp->xvec[skb->sp->len++] = x;
spin_lock(&x->lock);
if (unlikely(x->km.state != XFRM_STATE_VALID))
goto drop_unlock;
if (x->props.replay_window && xfrm_replay_check(x, seq)) {
xfrm_naudit_state_replay(x, skb, seq);
goto drop_unlock;
}
if (xfrm_state_check_expire(x))
goto drop_unlock;
XFRM_SKB_CB(skb)->seq = seq;
nexthdr = x->type->input(x, skb);
resume:
if (nexthdr <= 0)
goto drop_unlock;
skb->nh.raw[nhoff] = nexthdr;
if (x->props.replay_window)
xfrm_replay_advance(x, seq);
x->curlft.bytes += skb->len;
x->curlft.packets++;
spin_unlock(&x->lock);
if (x->mode->input(x, skb))
goto drop;
if (x->props.mode) { /* XXX */
decaps = 1;
break;
}
if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) < 0)
goto drop;
} while (!err);
skb->ip_summed = CHECKSUM_NONE;
nf_reset(skb);
if (decaps) {
if (!(skb->dev->flags&IFF_LOOPBACK)) {
dst_release(skb->dst);
skb->dst = NULL;
}
netif_rx(skb);
return -1;
} else {
skb->nh.ipv6h->payload_len = htons(skb->len);
__skb_push(skb, skb->data - skb->nh.raw);
NF_HOOK(PF_INET6, NF_IP6_PRE_ROUTING, skb, skb->dev, NULL,
dst_input);
return -1;
}
drop_unlock:
spin_unlock(&x->lock);
if (nexthdr == -EINPROGRESS)
return -1;
drop:
kfree_skb(skb);
return -1;
}