crypto: algif_aead - Require setkey before accept(2)

Some cipher implementations will crash if you try to use them
without calling setkey first.  This patch adds a check so that
the accept(2) call will fail with -ENOKEY if setkey hasn't been
done on the socket yet.

Fixes: 400c40cf78 ("crypto: algif - add AEAD support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Stephan Mueller 2017-04-24 11:15:23 +02:00 committed by Herbert Xu
parent a368f43d6e
commit 2a2a251f11
1 changed files with 149 additions and 8 deletions

View File

@ -44,6 +44,11 @@ struct aead_async_req {
char iv[];
};
struct aead_tfm {
struct crypto_aead *aead;
bool has_key;
};
struct aead_ctx {
struct aead_sg_list tsgl;
struct aead_async_rsgl first_rsgl;
@ -723,24 +728,146 @@ static struct proto_ops algif_aead_ops = {
.poll = aead_poll,
};
static int aead_check_key(struct socket *sock)
{
int err = 0;
struct sock *psk;
struct alg_sock *pask;
struct aead_tfm *tfm;
struct sock *sk = sock->sk;
struct alg_sock *ask = alg_sk(sk);
lock_sock(sk);
if (ask->refcnt)
goto unlock_child;
psk = ask->parent;
pask = alg_sk(ask->parent);
tfm = pask->private;
err = -ENOKEY;
lock_sock_nested(psk, SINGLE_DEPTH_NESTING);
if (!tfm->has_key)
goto unlock;
if (!pask->refcnt++)
sock_hold(psk);
ask->refcnt = 1;
sock_put(psk);
err = 0;
unlock:
release_sock(psk);
unlock_child:
release_sock(sk);
return err;
}
static int aead_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
size_t size)
{
int err;
err = aead_check_key(sock);
if (err)
return err;
return aead_sendmsg(sock, msg, size);
}
static ssize_t aead_sendpage_nokey(struct socket *sock, struct page *page,
int offset, size_t size, int flags)
{
int err;
err = aead_check_key(sock);
if (err)
return err;
return aead_sendpage(sock, page, offset, size, flags);
}
static int aead_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
size_t ignored, int flags)
{
int err;
err = aead_check_key(sock);
if (err)
return err;
return aead_recvmsg(sock, msg, ignored, flags);
}
static struct proto_ops algif_aead_ops_nokey = {
.family = PF_ALG,
.connect = sock_no_connect,
.socketpair = sock_no_socketpair,
.getname = sock_no_getname,
.ioctl = sock_no_ioctl,
.listen = sock_no_listen,
.shutdown = sock_no_shutdown,
.getsockopt = sock_no_getsockopt,
.mmap = sock_no_mmap,
.bind = sock_no_bind,
.accept = sock_no_accept,
.setsockopt = sock_no_setsockopt,
.release = af_alg_release,
.sendmsg = aead_sendmsg_nokey,
.sendpage = aead_sendpage_nokey,
.recvmsg = aead_recvmsg_nokey,
.poll = aead_poll,
};
static void *aead_bind(const char *name, u32 type, u32 mask)
{
return crypto_alloc_aead(name, type, mask);
struct aead_tfm *tfm;
struct crypto_aead *aead;
tfm = kzalloc(sizeof(*tfm), GFP_KERNEL);
if (!tfm)
return ERR_PTR(-ENOMEM);
aead = crypto_alloc_aead(name, type, mask);
if (IS_ERR(aead)) {
kfree(tfm);
return ERR_CAST(aead);
}
tfm->aead = aead;
return tfm;
}
static void aead_release(void *private)
{
crypto_free_aead(private);
struct aead_tfm *tfm = private;
crypto_free_aead(tfm->aead);
kfree(tfm);
}
static int aead_setauthsize(void *private, unsigned int authsize)
{
return crypto_aead_setauthsize(private, authsize);
struct aead_tfm *tfm = private;
return crypto_aead_setauthsize(tfm->aead, authsize);
}
static int aead_setkey(void *private, const u8 *key, unsigned int keylen)
{
return crypto_aead_setkey(private, key, keylen);
struct aead_tfm *tfm = private;
int err;
err = crypto_aead_setkey(tfm->aead, key, keylen);
tfm->has_key = !err;
return err;
}
static void aead_sock_destruct(struct sock *sk)
@ -757,12 +884,14 @@ static void aead_sock_destruct(struct sock *sk)
af_alg_release_parent(sk);
}
static int aead_accept_parent(void *private, struct sock *sk)
static int aead_accept_parent_nokey(void *private, struct sock *sk)
{
struct aead_ctx *ctx;
struct alg_sock *ask = alg_sk(sk);
unsigned int len = sizeof(*ctx) + crypto_aead_reqsize(private);
unsigned int ivlen = crypto_aead_ivsize(private);
struct aead_tfm *tfm = private;
struct crypto_aead *aead = tfm->aead;
unsigned int len = sizeof(*ctx) + crypto_aead_reqsize(aead);
unsigned int ivlen = crypto_aead_ivsize(aead);
ctx = sock_kmalloc(sk, len, GFP_KERNEL);
if (!ctx)
@ -789,7 +918,7 @@ static int aead_accept_parent(void *private, struct sock *sk)
ask->private = ctx;
aead_request_set_tfm(&ctx->aead_req, private);
aead_request_set_tfm(&ctx->aead_req, aead);
aead_request_set_callback(&ctx->aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
af_alg_complete, &ctx->completion);
@ -798,13 +927,25 @@ static int aead_accept_parent(void *private, struct sock *sk)
return 0;
}
static int aead_accept_parent(void *private, struct sock *sk)
{
struct aead_tfm *tfm = private;
if (!tfm->has_key)
return -ENOKEY;
return aead_accept_parent_nokey(private, sk);
}
static const struct af_alg_type algif_type_aead = {
.bind = aead_bind,
.release = aead_release,
.setkey = aead_setkey,
.setauthsize = aead_setauthsize,
.accept = aead_accept_parent,
.accept_nokey = aead_accept_parent_nokey,
.ops = &algif_aead_ops,
.ops_nokey = &algif_aead_ops_nokey,
.name = "aead",
.owner = THIS_MODULE
};