Am Montag, 24. April 2017, 11:03:13 CEST schrieb Herbert Xu:
Hi Herbert,
> On Mon, Apr 24, 2017 at 11:01:50AM +0200, Stephan Müller wrote:
> > Shall I send an updated patch with aead_sock_destruct cleared?
>
> Yes please.
Please find attached v2 with the discussed change.
---8<---
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.
Signed-off-by: Stephan Mueller <smuel...@chronox.de>
---
crypto/algif_aead.c | 157 +++++++++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 149 insertions(+), 8 deletions(-)
diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c
index 5a80537..e0d55ea 100644
--- a/crypto/algif_aead.c
+++ b/crypto/algif_aead.c
@@ -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
};
--
2.9.3
