1 files changed, 485 insertions, 0 deletions
diff --git a/crypto/af_alg.c b/crypto/af_alg.c
new file mode 100644
index 00000000000..6a3ad801158
--- /dev/null
+++ b/crypto/af_alg.c
@@ -0,0 +1,485 @@
+/*
+ * af_alg: User-space algorithm interface
+ *
+ * This file provides the user-space API for algorithms.
+ *
+ * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ */
+
+#include <linux/atomic.h>
+#include <crypto/if_alg.h>
+#include <linux/crypto.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/rwsem.h>
+#include <linux/security.h>
+
+struct alg_type_list {
+	const struct af_alg_type *type;
+	struct list_head list;
+};
+
+static atomic_long_t alg_memory_allocated;
+
+static struct proto alg_proto = {
+	.name			= "ALG",
+	.owner			= THIS_MODULE,
+	.memory_allocated	= &alg_memory_allocated,
+	.obj_size		= sizeof(struct alg_sock),
+};
+
+static LIST_HEAD(alg_types);
+static DECLARE_RWSEM(alg_types_sem);
+
+static const struct af_alg_type *alg_get_type(const char *name)
+{
+	const struct af_alg_type *type = ERR_PTR(-ENOENT);
+	struct alg_type_list *node;
+
+	down_read(&alg_types_sem);
+	list_for_each_entry(node, &alg_types, list) {
+		if (strcmp(node->type->name, name))
+			continue;
+
+		if (try_module_get(node->type->owner))
+			type = node->type;
+		break;
+	}
+	up_read(&alg_types_sem);
+
+	return type;
+}
+
+int af_alg_register_type(const struct af_alg_type *type)
+{
+	struct alg_type_list *node;
+	int err = -EEXIST;
+
+	down_write(&alg_types_sem);
+	list_for_each_entry(node, &alg_types, list) {
+		if (!strcmp(node->type->name, type->name))
+			goto unlock;
+	}
+
+	node = kmalloc(sizeof(*node), GFP_KERNEL);
+	err = -ENOMEM;
+	if (!node)
+		goto unlock;
+
+	type->ops->owner = THIS_MODULE;
+	node->type = type;
+	list_add(&node->list, &alg_types);
+	err = 0;
+
+unlock:
+	up_write(&alg_types_sem);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(af_alg_register_type);
+
+int af_alg_unregister_type(const struct af_alg_type *type)
+{
+	struct alg_type_list *node;
+	int err = -ENOENT;
+
+	down_write(&alg_types_sem);
+	list_for_each_entry(node, &alg_types, list) {
+		if (strcmp(node->type->name, type->name))
+			continue;
+
+		list_del(&node->list);
+		kfree(node);
+		err = 0;
+		break;
+	}
+	up_write(&alg_types_sem);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(af_alg_unregister_type);
+
+static void alg_do_release(const struct af_alg_type *type, void *private)
+{
+	if (!type)
+		return;
+
+	type->release(private);
+	module_put(type->owner);
+}
+
+int af_alg_release(struct socket *sock)
+{
+	if (sock->sk)
+		sock_put(sock->sk);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(af_alg_release);
+
+static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
+{
+	struct sock *sk = sock->sk;
+	struct alg_sock *ask = alg_sk(sk);
+	struct sockaddr_alg *sa = (void *)uaddr;
+	const struct af_alg_type *type;
+	void *private;
+
+	if (sock->state == SS_CONNECTED)
+		return -EINVAL;
+
+	if (addr_len != sizeof(*sa))
+		return -EINVAL;
+
+	sa->salg_type[sizeof(sa->salg_type) - 1] = 0;
+	sa->salg_name[sizeof(sa->salg_name) - 1] = 0;
+
+	type = alg_get_type(sa->salg_type);
+	if (IS_ERR(type) && PTR_ERR(type) == -ENOENT) {
+		request_module("algif-%s", sa->salg_type);
+		type = alg_get_type(sa->salg_type);
+	}
+
+	if (IS_ERR(type))
+		return PTR_ERR(type);
+
+	private = type->bind(sa->salg_name, sa->salg_feat, sa->salg_mask);
+	if (IS_ERR(private)) {
+		module_put(type->owner);
+		return PTR_ERR(private);
+	}
+
+	lock_sock(sk);
+
+	swap(ask->type, type);
+	swap(ask->private, private);
+
+	release_sock(sk);
+
+	alg_do_release(type, private);
+
+	return 0;
+}
+
+static int alg_setkey(struct sock *sk, char __user *ukey,
+		      unsigned int keylen)
+{
+	struct alg_sock *ask = alg_sk(sk);
+	const struct af_alg_type *type = ask->type;
+	u8 *key;
+	int err;
+
+	key = sock_kmalloc(sk, keylen, GFP_KERNEL);
+	if (!key)
+		return -ENOMEM;
+
+	err = -EFAULT;
+	if (copy_from_user(key, ukey, keylen))
+		goto out;
+
+	err = type->setkey(ask->private, key, keylen);
+
+out:
+	sock_kfree_s(sk, key, keylen);
+
+	return err;
+}
+
+static int alg_setsockopt(struct socket *sock, int level, int optname,
+			  char __user *optval, unsigned int optlen)
+{
+	struct sock *sk = sock->sk;
+	struct alg_sock *ask = alg_sk(sk);
+	const struct af_alg_type *type;
+	int err = -ENOPROTOOPT;
+
+	lock_sock(sk);
+	type = ask->type;
+
+	if (level != SOL_ALG || !type)
+		goto unlock;
+
+	switch (optname) {
+	case ALG_SET_KEY:
+		if (sock->state == SS_CONNECTED)
+			goto unlock;
+		if (!type->setkey)
+			goto unlock;
+
+		err = alg_setkey(sk, optval, optlen);
+	}
+
+unlock:
+	release_sock(sk);
+
+	return err;
+}
+
+int af_alg_accept(struct sock *sk, struct socket *newsock)
+{
+	struct alg_sock *ask = alg_sk(sk);
+	const struct af_alg_type *type;
+	struct sock *sk2;
+	int err;
+
+	lock_sock(sk);
+	type = ask->type;
+
+	err = -EINVAL;
+	if (!type)
+		goto unlock;
+
+	sk2 = sk_alloc(sock_net(sk), PF_ALG, GFP_KERNEL, &alg_proto);
+	err = -ENOMEM;
+	if (!sk2)
+		goto unlock;
+
+	sock_init_data(newsock, sk2);
+	sock_graft(sk2, newsock);
+	security_sk_clone(sk, sk2);
+
+	err = type->accept(ask->private, sk2);
+	if (err) {
+		sk_free(sk2);
+		goto unlock;
+	}
+
+	sk2->sk_family = PF_ALG;
+
+	sock_hold(sk);
+	alg_sk(sk2)->parent = sk;
+	alg_sk(sk2)->type = type;
+
+	newsock->ops = type->ops;
+	newsock->state = SS_CONNECTED;
+
+	err = 0;
+
+unlock:
+	release_sock(sk);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(af_alg_accept);
+
+static int alg_accept(struct socket *sock, struct socket *newsock, int flags)
+{
+	return af_alg_accept(sock->sk, newsock);
+}
+
+static const struct proto_ops alg_proto_ops = {
+	.family		=	PF_ALG,
+	.owner		=	THIS_MODULE,
+
+	.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,
+	.sendpage	=	sock_no_sendpage,
+	.sendmsg	=	sock_no_sendmsg,
+	.recvmsg	=	sock_no_recvmsg,
+	.poll		=	sock_no_poll,
+
+	.bind		=	alg_bind,
+	.release	=	af_alg_release,
+	.setsockopt	=	alg_setsockopt,
+	.accept		=	alg_accept,
+};
+
+static void alg_sock_destruct(struct sock *sk)
+{
+	struct alg_sock *ask = alg_sk(sk);
+
+	alg_do_release(ask->type, ask->private);
+}
+
+static int alg_create(struct net *net, struct socket *sock, int protocol,
+		      int kern)
+{
+	struct sock *sk;
+	int err;
+
+	if (sock->type != SOCK_SEQPACKET)
+		return -ESOCKTNOSUPPORT;
+	if (protocol != 0)
+		return -EPROTONOSUPPORT;
+
+	err = -ENOMEM;
+	sk = sk_alloc(net, PF_ALG, GFP_KERNEL, &alg_proto);
+	if (!sk)
+		goto out;
+
+	sock->ops = &alg_proto_ops;
+	sock_init_data(sock, sk);
+
+	sk->sk_family = PF_ALG;
+	sk->sk_destruct = alg_sock_destruct;
+
+	return 0;
+out:
+	return err;
+}
+
+static const struct net_proto_family alg_family = {
+	.family	=	PF_ALG,
+	.create	=	alg_create,
+	.owner	=	THIS_MODULE,
+};
+
+int af_alg_make_sg(struct af_alg_sgl *sgl, void __user *addr, int len,
+		   int write)
+{
+	unsigned long from = (unsigned long)addr;
+	unsigned long npages;
+	unsigned off;
+	int err;
+	int i;
+
+	err = -EFAULT;
+	if (!access_ok(write ? VERIFY_READ : VERIFY_WRITE, addr, len))
+		goto out;
+
+	off = from & ~PAGE_MASK;
+	npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+	if (npages > ALG_MAX_PAGES)
+		npages = ALG_MAX_PAGES;
+
+	err = get_user_pages_fast(from, npages, write, sgl->pages);
+	if (err < 0)
+		goto out;
+
+	npages = err;
+	err = -EINVAL;
+	if (WARN_ON(npages == 0))
+		goto out;
+
+	err = 0;
+
+	sg_init_table(sgl->sg, npages);
+
+	for (i = 0; i < npages; i++) {
+		int plen = min_t(int, len, PAGE_SIZE - off);
+
+		sg_set_page(sgl->sg + i, sgl->pages[i], plen, off);
+
+		off = 0;
+		len -= plen;
+		err += plen;
+	}
+
+out:
+	return err;
+}
+EXPORT_SYMBOL_GPL(af_alg_make_sg);
+
+void af_alg_free_sg(struct af_alg_sgl *sgl)
+{
+	int i;
+
+	i = 0;
+	do {
+		put_page(sgl->pages[i]);
+	} while (!sg_is_last(sgl->sg + (i++)));
+}
+EXPORT_SYMBOL_GPL(af_alg_free_sg);
+
+int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con)
+{
+	struct cmsghdr *cmsg;
+
+	for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+		if (!CMSG_OK(msg, cmsg))
+			return -EINVAL;
+		if (cmsg->cmsg_level != SOL_ALG)
+			continue;
+
+		switch(cmsg->cmsg_type) {
+		case ALG_SET_IV:
+			if (cmsg->cmsg_len < CMSG_LEN(sizeof(*con->iv)))
+				return -EINVAL;
+			con->iv = (void *)CMSG_DATA(cmsg);
+			if (cmsg->cmsg_len < CMSG_LEN(con->iv->ivlen +
+						      sizeof(*con->iv)))
+				return -EINVAL;
+			break;
+
+		case ALG_SET_OP:
+			if (cmsg->cmsg_len < CMSG_LEN(sizeof(u32)))
+				return -EINVAL;
+			con->op = *(u32 *)CMSG_DATA(cmsg);
+			break;
+
+		default:
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(af_alg_cmsg_send);
+
+int af_alg_wait_for_completion(int err, struct af_alg_completion *completion)
+{
+	switch (err) {
+	case -EINPROGRESS:
+	case -EBUSY:
+		wait_for_completion(&completion->completion);
+		reinit_completion(&completion->completion);
+		err = completion->err;
+		break;
+	};
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(af_alg_wait_for_completion);
+
+void af_alg_complete(struct crypto_async_request *req, int err)
+{
+	struct af_alg_completion *completion = req->data;
+
+	completion->err = err;
+	complete(&completion->completion);
+}
+EXPORT_SYMBOL_GPL(af_alg_complete);
+
+static int __init af_alg_init(void)
+{
+	int err = proto_register(&alg_proto, 0);
+
+	if (err)
+		goto out;
+
+	err = sock_register(&alg_family);
+	if (err != 0)
+		goto out_unregister_proto;
+
+out:
+	return err;
+
+out_unregister_proto:
+	proto_unregister(&alg_proto);
+	goto out;
+}
+
+static void __exit af_alg_exit(void)
+{
+	sock_unregister(PF_ALG);
+	proto_unregister(&alg_proto);
+}
+
+module_init(af_alg_init);
+module_exit(af_alg_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(AF_ALG);