1 files changed, 324 insertions, 0 deletions
diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c
new file mode 100644
index 00000000000..850246206b1
--- /dev/null
+++ b/crypto/algif_hash.c
@@ -0,0 +1,324 @@
+/*
+ * algif_hash: User-space interface for hash algorithms
+ *
+ * This file provides the user-space API for hash 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 <crypto/hash.h>
+#include <crypto/if_alg.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/net.h>
+#include <net/sock.h>
+
+struct hash_ctx {
+	struct af_alg_sgl sgl;
+
+	u8 *result;
+
+	struct af_alg_completion completion;
+
+	unsigned int len;
+	bool more;
+
+	struct ahash_request req;
+};
+
+static int hash_sendmsg(struct kiocb *unused, struct socket *sock,
+			struct msghdr *msg, size_t ignored)
+{
+	int limit = ALG_MAX_PAGES * PAGE_SIZE;
+	struct sock *sk = sock->sk;
+	struct alg_sock *ask = alg_sk(sk);
+	struct hash_ctx *ctx = ask->private;
+	unsigned long iovlen;
+	struct iovec *iov;
+	long copied = 0;
+	int err;
+
+	if (limit > sk->sk_sndbuf)
+		limit = sk->sk_sndbuf;
+
+	lock_sock(sk);
+	if (!ctx->more) {
+		err = crypto_ahash_init(&ctx->req);
+		if (err)
+			goto unlock;
+	}
+
+	ctx->more = 0;
+
+	for (iov = msg->msg_iov, iovlen = msg->msg_iovlen; iovlen > 0;
+	     iovlen--, iov++) {
+		unsigned long seglen = iov->iov_len;
+		char __user *from = iov->iov_base;
+
+		while (seglen) {
+			int len = min_t(unsigned long, seglen, limit);
+			int newlen;
+
+			newlen = af_alg_make_sg(&ctx->sgl, from, len, 0);
+			if (newlen < 0) {
+				err = copied ? 0 : newlen;
+				goto unlock;
+			}
+
+			ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL,
+						newlen);
+
+			err = af_alg_wait_for_completion(
+				crypto_ahash_update(&ctx->req),
+				&ctx->completion);
+
+			af_alg_free_sg(&ctx->sgl);
+
+			if (err)
+				goto unlock;
+
+			seglen -= newlen;
+			from += newlen;
+			copied += newlen;
+		}
+	}
+
+	err = 0;
+
+	ctx->more = msg->msg_flags & MSG_MORE;
+	if (!ctx->more) {
+		ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
+		err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
+						 &ctx->completion);
+	}
+
+unlock:
+	release_sock(sk);
+
+	return err ?: copied;
+}
+
+static ssize_t hash_sendpage(struct socket *sock, struct page *page,
+			     int offset, size_t size, int flags)
+{
+	struct sock *sk = sock->sk;
+	struct alg_sock *ask = alg_sk(sk);
+	struct hash_ctx *ctx = ask->private;
+	int err;
+
+	if (flags & MSG_SENDPAGE_NOTLAST)
+		flags |= MSG_MORE;
+
+	lock_sock(sk);
+	sg_init_table(ctx->sgl.sg, 1);
+	sg_set_page(ctx->sgl.sg, page, size, offset);
+
+	ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, ctx->result, size);
+
+	if (!(flags & MSG_MORE)) {
+		if (ctx->more)
+			err = crypto_ahash_finup(&ctx->req);
+		else
+			err = crypto_ahash_digest(&ctx->req);
+	} else {
+		if (!ctx->more) {
+			err = crypto_ahash_init(&ctx->req);
+			if (err)
+				goto unlock;
+		}
+
+		err = crypto_ahash_update(&ctx->req);
+	}
+
+	err = af_alg_wait_for_completion(err, &ctx->completion);
+	if (err)
+		goto unlock;
+
+	ctx->more = flags & MSG_MORE;
+
+unlock:
+	release_sock(sk);
+
+	return err ?: size;
+}
+
+static int hash_recvmsg(struct kiocb *unused, struct socket *sock,
+			struct msghdr *msg, size_t len, int flags)
+{
+	struct sock *sk = sock->sk;
+	struct alg_sock *ask = alg_sk(sk);
+	struct hash_ctx *ctx = ask->private;
+	unsigned ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
+	int err;
+
+	if (len > ds)
+		len = ds;
+	else if (len < ds)
+		msg->msg_flags |= MSG_TRUNC;
+
+	lock_sock(sk);
+	if (ctx->more) {
+		ctx->more = 0;
+		ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
+		err = af_alg_wait_for_completion(crypto_ahash_final(&ctx->req),
+						 &ctx->completion);
+		if (err)
+			goto unlock;
+	}
+
+	err = memcpy_toiovec(msg->msg_iov, ctx->result, len);
+
+unlock:
+	release_sock(sk);
+
+	return err ?: len;
+}
+
+static int hash_accept(struct socket *sock, struct socket *newsock, int flags)
+{
+	struct sock *sk = sock->sk;
+	struct alg_sock *ask = alg_sk(sk);
+	struct hash_ctx *ctx = ask->private;
+	struct ahash_request *req = &ctx->req;
+	char state[crypto_ahash_statesize(crypto_ahash_reqtfm(req))];
+	struct sock *sk2;
+	struct alg_sock *ask2;
+	struct hash_ctx *ctx2;
+	int err;
+
+	err = crypto_ahash_export(req, state);
+	if (err)
+		return err;
+
+	err = af_alg_accept(ask->parent, newsock);
+	if (err)
+		return err;
+
+	sk2 = newsock->sk;
+	ask2 = alg_sk(sk2);
+	ctx2 = ask2->private;
+	ctx2->more = 1;
+
+	err = crypto_ahash_import(&ctx2->req, state);
+	if (err) {
+		sock_orphan(sk2);
+		sock_put(sk2);
+	}
+
+	return err;
+}
+
+static struct proto_ops algif_hash_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,
+	.getsockopt	=	sock_no_getsockopt,
+	.mmap		=	sock_no_mmap,
+	.bind		=	sock_no_bind,
+	.setsockopt	=	sock_no_setsockopt,
+	.poll		=	sock_no_poll,
+
+	.release	=	af_alg_release,
+	.sendmsg	=	hash_sendmsg,
+	.sendpage	=	hash_sendpage,
+	.recvmsg	=	hash_recvmsg,
+	.accept		=	hash_accept,
+};
+
+static void *hash_bind(const char *name, u32 type, u32 mask)
+{
+	return crypto_alloc_ahash(name, type, mask);
+}
+
+static void hash_release(void *private)
+{
+	crypto_free_ahash(private);
+}
+
+static int hash_setkey(void *private, const u8 *key, unsigned int keylen)
+{
+	return crypto_ahash_setkey(private, key, keylen);
+}
+
+static void hash_sock_destruct(struct sock *sk)
+{
+	struct alg_sock *ask = alg_sk(sk);
+	struct hash_ctx *ctx = ask->private;
+
+	sock_kfree_s(sk, ctx->result,
+		     crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req)));
+	sock_kfree_s(sk, ctx, ctx->len);
+	af_alg_release_parent(sk);
+}
+
+static int hash_accept_parent(void *private, struct sock *sk)
+{
+	struct hash_ctx *ctx;
+	struct alg_sock *ask = alg_sk(sk);
+	unsigned len = sizeof(*ctx) + crypto_ahash_reqsize(private);
+	unsigned ds = crypto_ahash_digestsize(private);
+
+	ctx = sock_kmalloc(sk, len, GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
+	if (!ctx->result) {
+		sock_kfree_s(sk, ctx, len);
+		return -ENOMEM;
+	}
+
+	memset(ctx->result, 0, ds);
+
+	ctx->len = len;
+	ctx->more = 0;
+	af_alg_init_completion(&ctx->completion);
+
+	ask->private = ctx;
+
+	ahash_request_set_tfm(&ctx->req, private);
+	ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+				   af_alg_complete, &ctx->completion);
+
+	sk->sk_destruct = hash_sock_destruct;
+
+	return 0;
+}
+
+static const struct af_alg_type algif_type_hash = {
+	.bind		=	hash_bind,
+	.release	=	hash_release,
+	.setkey		=	hash_setkey,
+	.accept		=	hash_accept_parent,
+	.ops		=	&algif_hash_ops,
+	.name		=	"hash",
+	.owner		=	THIS_MODULE
+};
+
+static int __init algif_hash_init(void)
+{
+	return af_alg_register_type(&algif_type_hash);
+}
+
+static void __exit algif_hash_exit(void)
+{
+	int err = af_alg_unregister_type(&algif_type_hash);
+	BUG_ON(err);
+}
+
+module_init(algif_hash_init);
+module_exit(algif_hash_exit);
+MODULE_LICENSE("GPL");