[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/ipv4/esp4.c b/net/ipv4/esp4.c
index c404722..fac4f10 100644
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -439,32 +439,53 @@
kfree(esp);
}
-static int esp_init_state(struct xfrm_state *x)
+static int esp_init_aead(struct xfrm_state *x)
{
- struct esp_data *esp = NULL;
+ struct esp_data *esp = x->data;
+ struct crypto_aead *aead;
+ int err;
+
+ aead = crypto_alloc_aead(x->aead->alg_name, 0, 0);
+ err = PTR_ERR(aead);
+ if (IS_ERR(aead))
+ goto error;
+
+ esp->aead = aead;
+
+ err = crypto_aead_setkey(aead, x->aead->alg_key,
+ (x->aead->alg_key_len + 7) / 8);
+ if (err)
+ goto error;
+
+ err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8);
+ if (err)
+ goto error;
+
+error:
+ return err;
+}
+
+static int esp_init_authenc(struct xfrm_state *x)
+{
+ struct esp_data *esp = x->data;
struct crypto_aead *aead;
struct crypto_authenc_key_param *param;
struct rtattr *rta;
char *key;
char *p;
char authenc_name[CRYPTO_MAX_ALG_NAME];
- u32 align;
unsigned int keylen;
int err;
+ err = -EINVAL;
if (x->ealg == NULL)
- return -EINVAL;
+ goto error;
+ err = -ENAMETOOLONG;
if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, "authenc(%s,%s)",
x->aalg ? x->aalg->alg_name : "digest_null",
x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME)
- return -ENAMETOOLONG;
-
- esp = kzalloc(sizeof(*esp), GFP_KERNEL);
- if (esp == NULL)
- return -ENOMEM;
-
- x->data = esp;
+ goto error;
aead = crypto_alloc_aead(authenc_name, 0, 0);
err = PTR_ERR(aead);
@@ -512,8 +533,6 @@
goto free_key;
}
- esp->padlen = 0;
-
param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8);
memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8);
@@ -522,9 +541,35 @@
free_key:
kfree(key);
+error:
+ return err;
+}
+
+static int esp_init_state(struct xfrm_state *x)
+{
+ struct esp_data *esp;
+ struct crypto_aead *aead;
+ u32 align;
+ int err;
+
+ esp = kzalloc(sizeof(*esp), GFP_KERNEL);
+ if (esp == NULL)
+ return -ENOMEM;
+
+ x->data = esp;
+
+ if (x->aead)
+ err = esp_init_aead(x);
+ else
+ err = esp_init_authenc(x);
+
if (err)
goto error;
+ aead = esp->aead;
+
+ esp->padlen = 0;
+
x->props.header_len = sizeof(struct ip_esp_hdr) +
crypto_aead_ivsize(aead);
if (x->props.mode == XFRM_MODE_TUNNEL)
