Commit dff3bb06 authored by Steffen Klassert's avatar Steffen Klassert Committed by David S. Miller
Browse files

ah4: convert to ahash



This patch converts ah4 to the new ahash interface.
Signed-off-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 49cbf952
#include <crypto/hash.h>
#include <linux/err.h>
#include <linux/module.h>
#include <net/ip.h>
......@@ -5,10 +6,67 @@
#include <net/ah.h>
#include <linux/crypto.h>
#include <linux/pfkeyv2.h>
#include <linux/spinlock.h>
#include <linux/scatterlist.h>
#include <net/icmp.h>
#include <net/protocol.h>
struct ah_skb_cb {
struct xfrm_skb_cb xfrm;
void *tmp;
};
#define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0]))
static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags,
unsigned int size)
{
unsigned int len;
len = size + crypto_ahash_digestsize(ahash) +
(crypto_ahash_alignmask(ahash) &
~(crypto_tfm_ctx_alignment() - 1));
len = ALIGN(len, crypto_tfm_ctx_alignment());
len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash);
len = ALIGN(len, __alignof__(struct scatterlist));
len += sizeof(struct scatterlist) * nfrags;
return kmalloc(len, GFP_ATOMIC);
}
static inline u8 *ah_tmp_auth(void *tmp, unsigned int offset)
{
return tmp + offset;
}
static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp,
unsigned int offset)
{
return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1);
}
static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash,
u8 *icv)
{
struct ahash_request *req;
req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash),
crypto_tfm_ctx_alignment());
ahash_request_set_tfm(req, ahash);
return req;
}
static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash,
struct ahash_request *req)
{
return (void *)ALIGN((unsigned long)(req + 1) +
crypto_ahash_reqsize(ahash),
__alignof__(struct scatterlist));
}
/* Clear mutable options and find final destination to substitute
* into IP header for icv calculation. Options are already checked
......@@ -54,20 +112,72 @@ static int ip_clear_mutable_options(struct iphdr *iph, __be32 *daddr)
return 0;
}
static void ah_output_done(struct crypto_async_request *base, int err)
{
u8 *icv;
struct iphdr *iph;
struct sk_buff *skb = base->data;
struct xfrm_state *x = skb_dst(skb)->xfrm;
struct ah_data *ahp = x->data;
struct iphdr *top_iph = ip_hdr(skb);
struct ip_auth_hdr *ah = ip_auth_hdr(skb);
int ihl = ip_hdrlen(skb);
iph = AH_SKB_CB(skb)->tmp;
icv = ah_tmp_icv(ahp->ahash, iph, ihl);
memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
top_iph->tos = iph->tos;
top_iph->ttl = iph->ttl;
top_iph->frag_off = iph->frag_off;
if (top_iph->ihl != 5) {
top_iph->daddr = iph->daddr;
memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr));
}
err = ah->nexthdr;
kfree(AH_SKB_CB(skb)->tmp);
xfrm_output_resume(skb, err);
}
static int ah_output(struct xfrm_state *x, struct sk_buff *skb)
{
int err;
int nfrags;
int ihl;
u8 *icv;
struct sk_buff *trailer;
struct crypto_ahash *ahash;
struct ahash_request *req;
struct scatterlist *sg;
struct iphdr *iph, *top_iph;
struct ip_auth_hdr *ah;
struct ah_data *ahp;
union {
struct iphdr iph;
char buf[60];
} tmp_iph;
ahp = x->data;
ahash = ahp->ahash;
if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
goto out;
nfrags = err;
skb_push(skb, -skb_network_offset(skb));
ah = ip_auth_hdr(skb);
ihl = ip_hdrlen(skb);
err = -ENOMEM;
iph = ah_alloc_tmp(ahash, nfrags, ihl);
if (!iph)
goto out;
icv = ah_tmp_icv(ahash, iph, ihl);
req = ah_tmp_req(ahash, icv);
sg = ah_req_sg(ahash, req);
memset(ah->auth_data, 0, ahp->icv_trunc_len);
top_iph = ip_hdr(skb);
iph = &tmp_iph.iph;
iph->tos = top_iph->tos;
iph->ttl = top_iph->ttl;
......@@ -78,10 +188,9 @@ static int ah_output(struct xfrm_state *x, struct sk_buff *skb)
memcpy(iph+1, top_iph+1, top_iph->ihl*4 - sizeof(struct iphdr));
err = ip_clear_mutable_options(top_iph, &top_iph->daddr);
if (err)
goto error;
goto out_free;
}
ah = ip_auth_hdr(skb);
ah->nexthdr = *skb_mac_header(skb);
*skb_mac_header(skb) = IPPROTO_AH;
......@@ -91,20 +200,31 @@ static int ah_output(struct xfrm_state *x, struct sk_buff *skb)
top_iph->ttl = 0;
top_iph->check = 0;
ahp = x->data;
ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2;
ah->reserved = 0;
ah->spi = x->id.spi;
ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output);
spin_lock_bh(&x->lock);
err = ah_mac_digest(ahp, skb, ah->auth_data);
memcpy(ah->auth_data, ahp->work_icv, ahp->icv_trunc_len);
spin_unlock_bh(&x->lock);
sg_init_table(sg, nfrags);
skb_to_sgvec(skb, sg, 0, skb->len);
if (err)
goto error;
ahash_request_set_crypt(req, sg, icv, skb->len);
ahash_request_set_callback(req, 0, ah_output_done, skb);
AH_SKB_CB(skb)->tmp = iph;
err = crypto_ahash_digest(req);
if (err) {
if (err == -EINPROGRESS)
goto out;
if (err == -EBUSY)
err = NET_XMIT_DROP;
goto out_free;
}
memcpy(ah->auth_data, icv, ahp->icv_trunc_len);
top_iph->tos = iph->tos;
top_iph->ttl = iph->ttl;
......@@ -114,28 +234,67 @@ static int ah_output(struct xfrm_state *x, struct sk_buff *skb)
memcpy(top_iph+1, iph+1, top_iph->ihl*4 - sizeof(struct iphdr));
}
err = 0;
error:
out_free:
kfree(iph);
out:
return err;
}
static void ah_input_done(struct crypto_async_request *base, int err)
{
u8 *auth_data;
u8 *icv;
struct iphdr *work_iph;
struct sk_buff *skb = base->data;
struct xfrm_state *x = xfrm_input_state(skb);
struct ah_data *ahp = x->data;
struct ip_auth_hdr *ah = ip_auth_hdr(skb);
int ihl = ip_hdrlen(skb);
int ah_hlen = (ah->hdrlen + 2) << 2;
work_iph = AH_SKB_CB(skb)->tmp;
auth_data = ah_tmp_auth(work_iph, ihl);
icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len);
err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0;
if (err)
goto out;
skb->network_header += ah_hlen;
memcpy(skb_network_header(skb), work_iph, ihl);
__skb_pull(skb, ah_hlen + ihl);
skb_set_transport_header(skb, -ihl);
err = ah->nexthdr;
out:
kfree(AH_SKB_CB(skb)->tmp);
xfrm_input_resume(skb, err);
}
static int ah_input(struct xfrm_state *x, struct sk_buff *skb)
{
int ah_hlen;
int ihl;
int nexthdr;
int err = -EINVAL;
struct iphdr *iph;
int nfrags;
u8 *auth_data;
u8 *icv;
struct sk_buff *trailer;
struct crypto_ahash *ahash;
struct ahash_request *req;
struct scatterlist *sg;
struct iphdr *iph, *work_iph;
struct ip_auth_hdr *ah;
struct ah_data *ahp;
char work_buf[60];
int err = -ENOMEM;
if (!pskb_may_pull(skb, sizeof(*ah)))
goto out;
ah = (struct ip_auth_hdr *)skb->data;
ahp = x->data;
ahash = ahp->ahash;
nexthdr = ah->nexthdr;
ah_hlen = (ah->hdrlen + 2) << 2;
......@@ -156,9 +315,24 @@ static int ah_input(struct xfrm_state *x, struct sk_buff *skb)
ah = (struct ip_auth_hdr *)skb->data;
iph = ip_hdr(skb);
ihl = ip_hdrlen(skb);
if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
goto out;
nfrags = err;
work_iph = ah_alloc_tmp(ahash, nfrags, ihl + ahp->icv_trunc_len);
if (!work_iph)
goto out;
auth_data = ah_tmp_auth(work_iph, ihl);
icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len);
req = ah_tmp_req(ahash, icv);
sg = ah_req_sg(ahash, req);
ihl = skb->data - skb_network_header(skb);
memcpy(work_buf, iph, ihl);
memcpy(work_iph, iph, ihl);
memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
memset(ah->auth_data, 0, ahp->icv_trunc_len);
iph->ttl = 0;
iph->tos = 0;
......@@ -166,35 +340,44 @@ static int ah_input(struct xfrm_state *x, struct sk_buff *skb)
iph->check = 0;
if (ihl > sizeof(*iph)) {
__be32 dummy;
if (ip_clear_mutable_options(iph, &dummy))
goto out;
err = ip_clear_mutable_options(iph, &dummy);
if (err)
goto out_free;
}
spin_lock(&x->lock);
{
u8 auth_data[MAX_AH_AUTH_LEN];
skb_push(skb, ihl);
memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
skb_push(skb, ihl);
err = ah_mac_digest(ahp, skb, ah->auth_data);
if (err)
goto unlock;
if (memcmp(ahp->work_icv, auth_data, ahp->icv_trunc_len))
err = -EBADMSG;
sg_init_table(sg, nfrags);
skb_to_sgvec(skb, sg, 0, skb->len);
ahash_request_set_crypt(req, sg, icv, skb->len);
ahash_request_set_callback(req, 0, ah_input_done, skb);
AH_SKB_CB(skb)->tmp = work_iph;
err = crypto_ahash_digest(req);
if (err) {
if (err == -EINPROGRESS)
goto out;
if (err == -EBUSY)
err = NET_XMIT_DROP;
goto out_free;
}
unlock:
spin_unlock(&x->lock);
err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0;
if (err)
goto out;
goto out_free;
skb->network_header += ah_hlen;
memcpy(skb_network_header(skb), work_buf, ihl);
skb->transport_header = skb->network_header;
memcpy(skb_network_header(skb), work_iph, ihl);
__skb_pull(skb, ah_hlen + ihl);
skb_set_transport_header(skb, -ihl);
return nexthdr;
err = nexthdr;
out_free:
kfree (work_iph);
out:
return err;
}
......@@ -222,7 +405,7 @@ static int ah_init_state(struct xfrm_state *x)
{
struct ah_data *ahp = NULL;
struct xfrm_algo_desc *aalg_desc;
struct crypto_hash *tfm;
struct crypto_ahash *ahash;
if (!x->aalg)
goto error;
......@@ -231,31 +414,31 @@ static int ah_init_state(struct xfrm_state *x)
goto error;
ahp = kzalloc(sizeof(*ahp), GFP_KERNEL);
if (ahp == NULL)
if (!ahp)
return -ENOMEM;
tfm = crypto_alloc_hash(x->aalg->alg_name, 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(tfm))
ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0);
if (IS_ERR(ahash))
goto error;
ahp->tfm = tfm;
if (crypto_hash_setkey(tfm, x->aalg->alg_key,
(x->aalg->alg_key_len + 7) / 8))
ahp->ahash = ahash;
if (crypto_ahash_setkey(ahash, x->aalg->alg_key,
(x->aalg->alg_key_len + 7) / 8))
goto error;
/*
* Lookup the algorithm description maintained by xfrm_algo,
* verify crypto transform properties, and store information
* we need for AH processing. This lookup cannot fail here
* after a successful crypto_alloc_hash().
* after a successful crypto_alloc_ahash().
*/
aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
BUG_ON(!aalg_desc);
if (aalg_desc->uinfo.auth.icv_fullbits/8 !=
crypto_hash_digestsize(tfm)) {
crypto_ahash_digestsize(ahash)) {
printk(KERN_INFO "AH: %s digestsize %u != %hu\n",
x->aalg->alg_name, crypto_hash_digestsize(tfm),
x->aalg->alg_name, crypto_ahash_digestsize(ahash),
aalg_desc->uinfo.auth.icv_fullbits/8);
goto error;
}
......@@ -265,10 +448,6 @@ static int ah_init_state(struct xfrm_state *x)
BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN);
ahp->work_icv = kmalloc(ahp->icv_full_len, GFP_KERNEL);
if (!ahp->work_icv)
goto error;
x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) +
ahp->icv_trunc_len);
if (x->props.mode == XFRM_MODE_TUNNEL)
......@@ -279,8 +458,7 @@ static int ah_init_state(struct xfrm_state *x)
error:
if (ahp) {
kfree(ahp->work_icv);
crypto_free_hash(ahp->tfm);
crypto_free_ahash(ahp->ahash);
kfree(ahp);
}
return -EINVAL;
......@@ -293,8 +471,7 @@ static void ah_destroy(struct xfrm_state *x)
if (!ahp)
return;
kfree(ahp->work_icv);
crypto_free_hash(ahp->tfm);
crypto_free_ahash(ahp->ahash);
kfree(ahp);
}
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment