crypto/algif_skcipher.c

Source file repositories/reference/linux-study-clean/crypto/algif_skcipher.c

File Facts

System
Linux kernel
Corpus path
crypto/algif_skcipher.c
Extension
.c
Size
10175 bytes
Lines
409
Domain
Kernel Services
Bucket
crypto
Inferred role
Kernel Services: operation-table or driver-model contract
Status
pattern implementation candidate

Why This File Exists

Shared kernel service surface used by multiple subsystems, including helpers, cryptography, virtualization support, and async I/O infrastructure.

Dependency Surface

Detected Declarations

Annotated Snippet

static struct proto_ops algif_skcipher_ops = {
	.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,
	.mmap		=	sock_no_mmap,
	.bind		=	sock_no_bind,
	.accept		=	sock_no_accept,

	.release	=	af_alg_release,
	.sendmsg	=	skcipher_sendmsg,
	.recvmsg	=	skcipher_recvmsg,
	.poll		=	af_alg_poll,
};

static int skcipher_check_key(struct socket *sock)
{
	int err = 0;
	struct sock *psk;
	struct alg_sock *pask;
	struct crypto_skcipher *tfm;
	struct sock *sk = sock->sk;
	struct alg_sock *ask = alg_sk(sk);

	lock_sock(sk);
	if (!atomic_read(&ask->nokey_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 (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
		goto unlock;

	atomic_dec(&pask->nokey_refcnt);
	atomic_set(&ask->nokey_refcnt, 0);

	err = 0;

unlock:
	release_sock(psk);
unlock_child:
	release_sock(sk);

	return err;
}

static int skcipher_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
				  size_t size)
{
	int err;

	err = skcipher_check_key(sock);
	if (err)
		return err;

	return skcipher_sendmsg(sock, msg, size);
}

static int skcipher_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
				  size_t ignored, int flags)
{
	int err;

	err = skcipher_check_key(sock);
	if (err)
		return err;

	return skcipher_recvmsg(sock, msg, ignored, flags);
}

static struct proto_ops algif_skcipher_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,
	.mmap		=	sock_no_mmap,
	.bind		=	sock_no_bind,
	.accept		=	sock_no_accept,

Annotation

Implementation Notes