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Diffstat (limited to 'net/ipv4/ah4.c')
-rw-r--r--net/ipv4/ah4.c431
1 files changed, 338 insertions, 93 deletions
diff --git a/net/ipv4/ah4.c b/net/ipv4/ah4.c
index 8219b7e0968..a2afa89513a 100644
--- a/net/ipv4/ah4.c
+++ b/net/ipv4/ah4.c
@@ -1,22 +1,83 @@
+#define pr_fmt(fmt) "IPsec: " fmt
+
+#include <crypto/hash.h>
#include <linux/err.h>
#include <linux/module.h>
+#include <linux/slab.h>
#include <net/ip.h>
#include <net/xfrm.h>
#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
* for validity, so paranoia is not required. */
-static int ip_clear_mutable_options(struct iphdr *iph, __be32 *daddr)
+static int ip_clear_mutable_options(const struct iphdr *iph, __be32 *daddr)
{
- unsigned char * optptr = (unsigned char*)(iph+1);
+ unsigned char *optptr = (unsigned char *)(iph+1);
int l = iph->ihl*4 - sizeof(struct iphdr);
int optlen;
@@ -54,20 +115,79 @@ 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));
+ }
+
+ 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;
+ int seqhi_len = 0;
+ __be32 *seqhi;
+ int sglists = 0;
+ struct scatterlist *seqhisg;
+
+ 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);
+
+ if (x->props.flags & XFRM_STATE_ESN) {
+ sglists = 1;
+ seqhi_len = sizeof(*seqhi);
+ }
+ err = -ENOMEM;
+ iph = ah_alloc_tmp(ahash, nfrags + sglists, ihl + seqhi_len);
+ if (!iph)
+ goto out;
+ seqhi = (__be32 *)((char *)iph + ihl);
+ icv = ah_tmp_icv(ahash, seqhi, seqhi_len);
+ req = ah_tmp_req(ahash, icv);
+ sg = ah_req_sg(ahash, req);
+ seqhisg = sg + nfrags;
+
+ 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 +198,9 @@ 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 +210,39 @@ 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;
+ if (x->props.flags & XFRM_STATE_ALIGN4)
+ ah->hdrlen = (XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2;
+ else
+ 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);
+ ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
- 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 + sglists);
+ skb_to_sgvec_nomark(skb, sg, 0, skb->len);
- if (err)
- goto error;
+ if (x->props.flags & XFRM_STATE_ESN) {
+ /* Attach seqhi sg right after packet payload */
+ *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi);
+ sg_set_buf(seqhisg, seqhi, seqhi_len);
+ }
+ ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_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;
@@ -114,51 +252,127 @@ 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;
+
+ err = ah->nexthdr;
+
+ skb->network_header += ah_hlen;
+ memcpy(skb_network_header(skb), work_iph, ihl);
+ __skb_pull(skb, ah_hlen + ihl);
+
+ if (x->props.mode == XFRM_MODE_TUNNEL)
+ skb_reset_transport_header(skb);
+ else
+ skb_set_transport_header(skb, -ihl);
+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;
+ int seqhi_len = 0;
+ __be32 *seqhi;
+ int sglists = 0;
+ struct scatterlist *seqhisg;
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;
- if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) &&
- ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len))
- goto out;
+ if (x->props.flags & XFRM_STATE_ALIGN4) {
+ if (ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_full_len) &&
+ ah_hlen != XFRM_ALIGN4(sizeof(*ah) + ahp->icv_trunc_len))
+ goto out;
+ } else {
+ if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) &&
+ ah_hlen != XFRM_ALIGN8(sizeof(*ah) + 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))
+ if (skb_unclone(skb, GFP_ATOMIC))
goto out;
skb->ip_summed = CHECKSUM_NONE;
+
+ if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
+ goto out;
+ nfrags = err;
+
ah = (struct ip_auth_hdr *)skb->data;
iph = ip_hdr(skb);
+ ihl = ip_hdrlen(skb);
- ihl = skb->data - skb_network_header(skb);
- memcpy(work_buf, iph, ihl);
+ if (x->props.flags & XFRM_STATE_ESN) {
+ sglists = 1;
+ seqhi_len = sizeof(*seqhi);
+ }
+
+ work_iph = ah_alloc_tmp(ahash, nfrags + sglists, ihl +
+ ahp->icv_trunc_len + seqhi_len);
+ if (!work_iph)
+ goto out;
+
+ seqhi = (__be32 *)((char *)work_iph + ihl);
+ auth_data = ah_tmp_auth(seqhi, seqhi_len);
+ icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len);
+ req = ah_tmp_req(ahash, icv);
+ sg = ah_req_sg(ahash, req);
+ seqhisg = sg + nfrags;
+
+ 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;
@@ -166,62 +380,90 @@ 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 + sglists);
+ skb_to_sgvec_nomark(skb, sg, 0, skb->len);
+
+ if (x->props.flags & XFRM_STATE_ESN) {
+ /* Attach seqhi sg right after packet payload */
+ *seqhi = XFRM_SKB_CB(skb)->seq.input.hi;
+ sg_set_buf(seqhisg, seqhi, seqhi_len);
}
-unlock:
- spin_unlock(&x->lock);
+ ahash_request_set_crypt(req, sg, icv, skb->len + seqhi_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;
+ goto out_free;
+ }
+
+ 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);
+ if (x->props.mode == XFRM_MODE_TUNNEL)
+ skb_reset_transport_header(skb);
+ else
+ skb_set_transport_header(skb, -ihl);
- return nexthdr;
+ err = nexthdr;
+out_free:
+ kfree (work_iph);
out:
return err;
}
-static void ah4_err(struct sk_buff *skb, u32 info)
+static int ah4_err(struct sk_buff *skb, u32 info)
{
- struct iphdr *iph = (struct iphdr*)skb->data;
- struct ip_auth_hdr *ah = (struct ip_auth_hdr*)(skb->data+(iph->ihl<<2));
+ struct net *net = dev_net(skb->dev);
+ const struct iphdr *iph = (const struct iphdr *)skb->data;
+ struct ip_auth_hdr *ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2));
struct xfrm_state *x;
- if (icmp_hdr(skb)->type != ICMP_DEST_UNREACH ||
- icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
- return;
+ switch (icmp_hdr(skb)->type) {
+ case ICMP_DEST_UNREACH:
+ if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
+ return 0;
+ case ICMP_REDIRECT:
+ break;
+ default:
+ return 0;
+ }
- x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, ah->spi, IPPROTO_AH, AF_INET);
+ x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
+ ah->spi, IPPROTO_AH, AF_INET);
if (!x)
- return;
- printk(KERN_DEBUG "pmtu discovery on SA AH/%08x/%08x\n",
- ntohl(ah->spi), ntohl(iph->daddr));
+ return 0;
+
+ if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
+ ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_AH, 0);
+ else
+ ipv4_redirect(skb, net, 0, 0, IPPROTO_AH, 0);
xfrm_state_put(x);
+
+ return 0;
}
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;
@@ -230,46 +472,47 @@ 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)) {
- printk(KERN_INFO "AH: %s digestsize %u != %hu\n",
- x->aalg->alg_name, crypto_hash_digestsize(tfm),
- aalg_desc->uinfo.auth.icv_fullbits/8);
+ crypto_ahash_digestsize(ahash)) {
+ pr_info("%s: %s digestsize %u != %hu\n",
+ __func__, x->aalg->alg_name,
+ crypto_ahash_digestsize(ahash),
+ aalg_desc->uinfo.auth.icv_fullbits / 8);
goto error;
}
ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8;
- ahp->icv_trunc_len = aalg_desc->uinfo.auth.icv_truncbits/8;
+ ahp->icv_trunc_len = x->aalg->alg_trunc_len/8;
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.flags & XFRM_STATE_ALIGN4)
+ x->props.header_len = XFRM_ALIGN4(sizeof(struct ip_auth_hdr) +
+ ahp->icv_trunc_len);
+ else
+ x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) +
+ ahp->icv_trunc_len);
if (x->props.mode == XFRM_MODE_TUNNEL)
x->props.header_len += sizeof(struct iphdr);
x->data = ahp;
@@ -278,8 +521,7 @@ 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;
@@ -292,13 +534,14 @@ static void ah_destroy(struct xfrm_state *x)
if (!ahp)
return;
- kfree(ahp->work_icv);
- ahp->work_icv = NULL;
- crypto_free_hash(ahp->tfm);
- ahp->tfm = NULL;
+ crypto_free_ahash(ahp->ahash);
kfree(ahp);
}
+static int ah4_rcv_cb(struct sk_buff *skb, int err)
+{
+ return 0;
+}
static const struct xfrm_type ah_type =
{
@@ -312,20 +555,22 @@ static const struct xfrm_type ah_type =
.output = ah_output
};
-static struct net_protocol ah4_protocol = {
+static struct xfrm4_protocol ah4_protocol = {
.handler = xfrm4_rcv,
+ .input_handler = xfrm_input,
+ .cb_handler = ah4_rcv_cb,
.err_handler = ah4_err,
- .no_policy = 1,
+ .priority = 0,
};
static int __init ah4_init(void)
{
if (xfrm_register_type(&ah_type, AF_INET) < 0) {
- printk(KERN_INFO "ip ah init: can't add xfrm type\n");
+ pr_info("%s: can't add xfrm type\n", __func__);
return -EAGAIN;
}
- if (inet_add_protocol(&ah4_protocol, IPPROTO_AH) < 0) {
- printk(KERN_INFO "ip ah init: can't add protocol\n");
+ if (xfrm4_protocol_register(&ah4_protocol, IPPROTO_AH) < 0) {
+ pr_info("%s: can't add protocol\n", __func__);
xfrm_unregister_type(&ah_type, AF_INET);
return -EAGAIN;
}
@@ -334,10 +579,10 @@ static int __init ah4_init(void)
static void __exit ah4_fini(void)
{
- if (inet_del_protocol(&ah4_protocol, IPPROTO_AH) < 0)
- printk(KERN_INFO "ip ah close: can't remove protocol\n");
+ if (xfrm4_protocol_deregister(&ah4_protocol, IPPROTO_AH) < 0)
+ pr_info("%s: can't remove protocol\n", __func__);
if (xfrm_unregister_type(&ah_type, AF_INET) < 0)
- printk(KERN_INFO "ip ah close: can't remove xfrm type\n");
+ pr_info("%s: can't remove xfrm type\n", __func__);
}
module_init(ah4_init);