Allow user space to seed / reset the RNG via a setsockopt.
This patch reuses alg_setkey to copy data into the kernel. The
alg_setkey is now used for two mechanisms: setkey and seeding.
The function is extended by the providing the function pointer
to the function handling the copied data.
As the alg_setkey is now usable for more than just setkey, it is renamed
to alg_setop.
Signed-off-by: Stephan Mueller <smuel...@chronox.de>
---
crypto/af_alg.c | 29 +++++++++++++++++++----------
include/crypto/if_alg.h | 1 +
include/uapi/linux/if_alg.h | 1 +
3 files changed, 21 insertions(+), 10 deletions(-)
diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index 547c369..d1eb1e9 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -169,26 +169,27 @@ static int alg_bind(struct socket *sock, struct sockaddr
*uaddr, int addr_len)
return 0;
}
-static int alg_setkey(struct sock *sk, char __user *ukey,
- unsigned int keylen)
+static int alg_setop(struct sock *sk, char __user *udata,
+ unsigned int datalen,
+ int (*handler)(void *private, const u8 *data,
+ unsigned int datalen))
{
struct alg_sock *ask = alg_sk(sk);
- const struct af_alg_type *type = ask->type;
- u8 *key;
+ u8 *data;
int err;
- key = sock_kmalloc(sk, keylen, GFP_KERNEL);
- if (!key)
+ data = sock_kmalloc(sk, datalen, GFP_KERNEL);
+ if (!data)
return -ENOMEM;
err = -EFAULT;
- if (copy_from_user(key, ukey, keylen))
+ if (copy_from_user(data, udata, datalen))
goto out;
- err = type->setkey(ask->private, key, keylen);
+ err = handler(ask->private, data, datalen);
out:
- sock_kfree_s(sk, key, keylen);
+ sock_kfree_s(sk, data, datalen);
return err;
}
@@ -214,7 +215,7 @@ static int alg_setsockopt(struct socket *sock, int level,
int optname,
if (!type->setkey)
goto unlock;
- err = alg_setkey(sk, optval, optlen);
+ err = alg_setop(sk, optval, optlen, type->setkey);
break;
case ALG_SET_AEAD_AUTHSIZE:
if (sock->state == SS_CONNECTED)
@@ -222,6 +223,14 @@ static int alg_setsockopt(struct socket *sock, int level,
int optname,
if (!type->setauthsize)
goto unlock;
err = type->setauthsize(ask->private, optlen);
+ break;
+ case ALG_SET_RNG_SEED:
+ if (sock->state == SS_CONNECTED)
+ goto unlock;
+ if (!type->setseed)
+ goto unlock;
+
+ err = alg_setop(sk, optval, optlen, type->setseed);
}
unlock:
diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h
index 5c7b6c5..0808ed1 100644
--- a/include/crypto/if_alg.h
+++ b/include/crypto/if_alg.h
@@ -51,6 +51,7 @@ struct af_alg_type {
int (*setkey)(void *private, const u8 *key, unsigned int keylen);
int (*accept)(void *private, struct sock *sk);
int (*setauthsize)(void *private, unsigned int authsize);
+ int (*setseed)(void *private, const u8 *seed, unsigned int seedlen);
struct proto_ops *ops;
struct module *owner;
diff --git a/include/uapi/linux/if_alg.h b/include/uapi/linux/if_alg.h
index f2acd2f..973dcca 100644
--- a/include/uapi/linux/if_alg.h
+++ b/include/uapi/linux/if_alg.h
@@ -34,6 +34,7 @@ struct af_alg_iv {
#define ALG_SET_OP 3
#define ALG_SET_AEAD_ASSOCLEN 4
#define ALG_SET_AEAD_AUTHSIZE 5
+#define ALG_SET_RNG_SEED 6
/* Operations */
#define ALG_OP_DECRYPT 0
--
2.1.0
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
