lkml.org 
[lkml]   [2014]   [Dec]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v5 5/8] crypto: AF_ALG: add user space interface for RNG
Date
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 <smueller@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



\
 
 \ /
  Last update: 2014-12-07 23:41    [W:0.129 / U:0.220 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site