[IPSEC]: Add support for combined mode algorithms
This patch adds support for combined mode algorithms with GCM being
the first algorithm supported.
Combined mode algorithms can be added through the xfrm_user interface
using the new algorithm payload type XFRMA_ALG_AEAD. Each algorithms
is identified by its name and the ICV length.
For the purposes of matching algorithms in xfrm_tmpl structures,
combined mode algorithms occupy the same name space as encryption
algorithms. This is in line with how they are negotiated using IKE.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/xfrm_algo.c b/net/xfrm/xfrm_algo.c
index 02e3ecf..6cc1525 100644
--- a/net/xfrm/xfrm_algo.c
+++ b/net/xfrm/xfrm_algo.c
@@ -28,6 +28,105 @@
* that instantiated crypto transforms have correct parameters for IPsec
* purposes.
*/
+static struct xfrm_algo_desc aead_list[] = {
+{
+ .name = "rfc4106(gcm(aes))",
+
+ .uinfo = {
+ .aead = {
+ .icv_truncbits = 64,
+ }
+ },
+
+ .desc = {
+ .sadb_alg_id = SADB_X_EALG_AES_GCM_ICV8,
+ .sadb_alg_ivlen = 8,
+ .sadb_alg_minbits = 128,
+ .sadb_alg_maxbits = 256
+ }
+},
+{
+ .name = "rfc4106(gcm(aes))",
+
+ .uinfo = {
+ .aead = {
+ .icv_truncbits = 96,
+ }
+ },
+
+ .desc = {
+ .sadb_alg_id = SADB_X_EALG_AES_GCM_ICV12,
+ .sadb_alg_ivlen = 8,
+ .sadb_alg_minbits = 128,
+ .sadb_alg_maxbits = 256
+ }
+},
+{
+ .name = "rfc4106(gcm(aes))",
+
+ .uinfo = {
+ .aead = {
+ .icv_truncbits = 128,
+ }
+ },
+
+ .desc = {
+ .sadb_alg_id = SADB_X_EALG_AES_GCM_ICV16,
+ .sadb_alg_ivlen = 8,
+ .sadb_alg_minbits = 128,
+ .sadb_alg_maxbits = 256
+ }
+},
+{
+ .name = "rfc4309(ccm(aes))",
+
+ .uinfo = {
+ .aead = {
+ .icv_truncbits = 64,
+ }
+ },
+
+ .desc = {
+ .sadb_alg_id = SADB_X_EALG_AES_CCM_ICV8,
+ .sadb_alg_ivlen = 8,
+ .sadb_alg_minbits = 128,
+ .sadb_alg_maxbits = 256
+ }
+},
+{
+ .name = "rfc4309(ccm(aes))",
+
+ .uinfo = {
+ .aead = {
+ .icv_truncbits = 96,
+ }
+ },
+
+ .desc = {
+ .sadb_alg_id = SADB_X_EALG_AES_CCM_ICV12,
+ .sadb_alg_ivlen = 8,
+ .sadb_alg_minbits = 128,
+ .sadb_alg_maxbits = 256
+ }
+},
+{
+ .name = "rfc4309(ccm(aes))",
+
+ .uinfo = {
+ .aead = {
+ .icv_truncbits = 128,
+ }
+ },
+
+ .desc = {
+ .sadb_alg_id = SADB_X_EALG_AES_CCM_ICV16,
+ .sadb_alg_ivlen = 8,
+ .sadb_alg_minbits = 128,
+ .sadb_alg_maxbits = 256
+ }
+},
+};
+
static struct xfrm_algo_desc aalg_list[] = {
{
.name = "hmac(digest_null)",
@@ -332,6 +431,11 @@
},
};
+static inline int aead_entries(void)
+{
+ return ARRAY_SIZE(aead_list);
+}
+
static inline int aalg_entries(void)
{
return ARRAY_SIZE(aalg_list);
@@ -354,6 +458,13 @@
u32 mask;
};
+static const struct xfrm_algo_list xfrm_aead_list = {
+ .algs = aead_list,
+ .entries = ARRAY_SIZE(aead_list),
+ .type = CRYPTO_ALG_TYPE_AEAD,
+ .mask = CRYPTO_ALG_TYPE_MASK,
+};
+
static const struct xfrm_algo_list xfrm_aalg_list = {
.algs = aalg_list,
.entries = ARRAY_SIZE(aalg_list),
@@ -461,6 +572,33 @@
}
EXPORT_SYMBOL_GPL(xfrm_calg_get_byname);
+struct xfrm_aead_name {
+ const char *name;
+ int icvbits;
+};
+
+static int xfrm_aead_name_match(const struct xfrm_algo_desc *entry,
+ const void *data)
+{
+ const struct xfrm_aead_name *aead = data;
+ const char *name = aead->name;
+
+ return aead->icvbits == entry->uinfo.aead.icv_truncbits && name &&
+ !strcmp(name, entry->name);
+}
+
+struct xfrm_algo_desc *xfrm_aead_get_byname(char *name, int icv_len, int probe)
+{
+ struct xfrm_aead_name data = {
+ .name = name,
+ .icvbits = icv_len,
+ };
+
+ return xfrm_find_algo(&xfrm_aead_list, xfrm_aead_name_match, &data,
+ probe);
+}
+EXPORT_SYMBOL_GPL(xfrm_aead_get_byname);
+
struct xfrm_algo_desc *xfrm_aalg_get_byidx(unsigned int idx)
{
if (idx >= aalg_entries())