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-rw-r--r--crypto/algif_hash.c473
1 files changed, 473 insertions, 0 deletions
diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c
new file mode 100644
index 0000000000..82c44d4899
--- /dev/null
+++ b/crypto/algif_hash.c
@@ -0,0 +1,473 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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>
+ */
+
+#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 crypto_wait wait;
+
+ unsigned int len;
+ bool more;
+
+ struct ahash_request req;
+};
+
+static int hash_alloc_result(struct sock *sk, struct hash_ctx *ctx)
+{
+ unsigned ds;
+
+ if (ctx->result)
+ return 0;
+
+ ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
+
+ ctx->result = sock_kmalloc(sk, ds, GFP_KERNEL);
+ if (!ctx->result)
+ return -ENOMEM;
+
+ memset(ctx->result, 0, ds);
+
+ return 0;
+}
+
+static void hash_free_result(struct sock *sk, struct hash_ctx *ctx)
+{
+ unsigned ds;
+
+ if (!ctx->result)
+ return;
+
+ ds = crypto_ahash_digestsize(crypto_ahash_reqtfm(&ctx->req));
+
+ sock_kzfree_s(sk, ctx->result, ds);
+ ctx->result = NULL;
+}
+
+static int hash_sendmsg(struct socket *sock, struct msghdr *msg,
+ size_t ignored)
+{
+ struct sock *sk = sock->sk;
+ struct alg_sock *ask = alg_sk(sk);
+ struct hash_ctx *ctx = ask->private;
+ ssize_t copied = 0;
+ size_t len, max_pages, npages;
+ bool continuing, need_init = false;
+ int err;
+
+ max_pages = min_t(size_t, ALG_MAX_PAGES,
+ DIV_ROUND_UP(sk->sk_sndbuf, PAGE_SIZE));
+
+ lock_sock(sk);
+ continuing = ctx->more;
+
+ if (!continuing) {
+ /* Discard a previous request that wasn't marked MSG_MORE. */
+ hash_free_result(sk, ctx);
+ if (!msg_data_left(msg))
+ goto done; /* Zero-length; don't start new req */
+ need_init = true;
+ } else if (!msg_data_left(msg)) {
+ /*
+ * No data - finalise the prev req if MSG_MORE so any error
+ * comes out here.
+ */
+ if (!(msg->msg_flags & MSG_MORE)) {
+ err = hash_alloc_result(sk, ctx);
+ if (err)
+ goto unlock_free;
+ ahash_request_set_crypt(&ctx->req, NULL,
+ ctx->result, 0);
+ err = crypto_wait_req(crypto_ahash_final(&ctx->req),
+ &ctx->wait);
+ if (err)
+ goto unlock_free;
+ }
+ goto done_more;
+ }
+
+ while (msg_data_left(msg)) {
+ ctx->sgl.sgt.sgl = ctx->sgl.sgl;
+ ctx->sgl.sgt.nents = 0;
+ ctx->sgl.sgt.orig_nents = 0;
+
+ err = -EIO;
+ npages = iov_iter_npages(&msg->msg_iter, max_pages);
+ if (npages == 0)
+ goto unlock_free;
+
+ sg_init_table(ctx->sgl.sgl, npages);
+
+ ctx->sgl.need_unpin = iov_iter_extract_will_pin(&msg->msg_iter);
+
+ err = extract_iter_to_sg(&msg->msg_iter, LONG_MAX,
+ &ctx->sgl.sgt, npages, 0);
+ if (err < 0)
+ goto unlock_free;
+ len = err;
+ sg_mark_end(ctx->sgl.sgt.sgl + ctx->sgl.sgt.nents - 1);
+
+ if (!msg_data_left(msg)) {
+ err = hash_alloc_result(sk, ctx);
+ if (err)
+ goto unlock_free;
+ }
+
+ ahash_request_set_crypt(&ctx->req, ctx->sgl.sgt.sgl,
+ ctx->result, len);
+
+ if (!msg_data_left(msg) && !continuing &&
+ !(msg->msg_flags & MSG_MORE)) {
+ err = crypto_ahash_digest(&ctx->req);
+ } else {
+ if (need_init) {
+ err = crypto_wait_req(
+ crypto_ahash_init(&ctx->req),
+ &ctx->wait);
+ if (err)
+ goto unlock_free;
+ need_init = false;
+ }
+
+ if (msg_data_left(msg) || (msg->msg_flags & MSG_MORE))
+ err = crypto_ahash_update(&ctx->req);
+ else
+ err = crypto_ahash_finup(&ctx->req);
+ continuing = true;
+ }
+
+ err = crypto_wait_req(err, &ctx->wait);
+ if (err)
+ goto unlock_free;
+
+ copied += len;
+ af_alg_free_sg(&ctx->sgl);
+ }
+
+done_more:
+ ctx->more = msg->msg_flags & MSG_MORE;
+done:
+ err = 0;
+unlock:
+ release_sock(sk);
+ return copied ?: err;
+
+unlock_free:
+ af_alg_free_sg(&ctx->sgl);
+ hash_free_result(sk, ctx);
+ ctx->more = false;
+ goto unlock;
+}
+
+static int hash_recvmsg(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));
+ bool result;
+ int err;
+
+ if (len > ds)
+ len = ds;
+ else if (len < ds)
+ msg->msg_flags |= MSG_TRUNC;
+
+ lock_sock(sk);
+ result = ctx->result;
+ err = hash_alloc_result(sk, ctx);
+ if (err)
+ goto unlock;
+
+ ahash_request_set_crypt(&ctx->req, NULL, ctx->result, 0);
+
+ if (!result && !ctx->more) {
+ err = crypto_wait_req(crypto_ahash_init(&ctx->req),
+ &ctx->wait);
+ if (err)
+ goto unlock;
+ }
+
+ if (!result || ctx->more) {
+ ctx->more = false;
+ err = crypto_wait_req(crypto_ahash_final(&ctx->req),
+ &ctx->wait);
+ if (err)
+ goto unlock;
+ }
+
+ err = memcpy_to_msg(msg, ctx->result, len);
+
+unlock:
+ hash_free_result(sk, ctx);
+ release_sock(sk);
+
+ return err ?: len;
+}
+
+static int hash_accept(struct socket *sock, struct socket *newsock, int flags,
+ bool kern)
+{
+ struct sock *sk = sock->sk;
+ struct alg_sock *ask = alg_sk(sk);
+ struct hash_ctx *ctx = ask->private;
+ struct ahash_request *req = &ctx->req;
+ struct crypto_ahash *tfm;
+ struct sock *sk2;
+ struct alg_sock *ask2;
+ struct hash_ctx *ctx2;
+ char *state;
+ bool more;
+ int err;
+
+ tfm = crypto_ahash_reqtfm(req);
+ state = kmalloc(crypto_ahash_statesize(tfm), GFP_KERNEL);
+ err = -ENOMEM;
+ if (!state)
+ goto out;
+
+ lock_sock(sk);
+ more = ctx->more;
+ err = more ? crypto_ahash_export(req, state) : 0;
+ release_sock(sk);
+
+ if (err)
+ goto out_free_state;
+
+ err = af_alg_accept(ask->parent, newsock, kern);
+ if (err)
+ goto out_free_state;
+
+ sk2 = newsock->sk;
+ ask2 = alg_sk(sk2);
+ ctx2 = ask2->private;
+ ctx2->more = more;
+
+ if (!more)
+ goto out_free_state;
+
+ err = crypto_ahash_import(&ctx2->req, state);
+ if (err) {
+ sock_orphan(sk2);
+ sock_put(sk2);
+ }
+
+out_free_state:
+ kfree_sensitive(state);
+
+out:
+ 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,
+ .mmap = sock_no_mmap,
+ .bind = sock_no_bind,
+
+ .release = af_alg_release,
+ .sendmsg = hash_sendmsg,
+ .recvmsg = hash_recvmsg,
+ .accept = hash_accept,
+};
+
+static int hash_check_key(struct socket *sock)
+{
+ int err = 0;
+ struct sock *psk;
+ struct alg_sock *pask;
+ struct crypto_ahash *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_ahash_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 hash_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
+ size_t size)
+{
+ int err;
+
+ err = hash_check_key(sock);
+ if (err)
+ return err;
+
+ return hash_sendmsg(sock, msg, size);
+}
+
+static int hash_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
+ size_t ignored, int flags)
+{
+ int err;
+
+ err = hash_check_key(sock);
+ if (err)
+ return err;
+
+ return hash_recvmsg(sock, msg, ignored, flags);
+}
+
+static int hash_accept_nokey(struct socket *sock, struct socket *newsock,
+ int flags, bool kern)
+{
+ int err;
+
+ err = hash_check_key(sock);
+ if (err)
+ return err;
+
+ return hash_accept(sock, newsock, flags, kern);
+}
+
+static struct proto_ops algif_hash_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,
+
+ .release = af_alg_release,
+ .sendmsg = hash_sendmsg_nokey,
+ .recvmsg = hash_recvmsg_nokey,
+ .accept = hash_accept_nokey,
+};
+
+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;
+
+ hash_free_result(sk, ctx);
+ sock_kfree_s(sk, ctx, ctx->len);
+ af_alg_release_parent(sk);
+}
+
+static int hash_accept_parent_nokey(void *private, struct sock *sk)
+{
+ struct crypto_ahash *tfm = private;
+ struct alg_sock *ask = alg_sk(sk);
+ struct hash_ctx *ctx;
+ unsigned int len = sizeof(*ctx) + crypto_ahash_reqsize(tfm);
+
+ ctx = sock_kmalloc(sk, len, GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ ctx->result = NULL;
+ ctx->len = len;
+ ctx->more = false;
+ crypto_init_wait(&ctx->wait);
+
+ ask->private = ctx;
+
+ ahash_request_set_tfm(&ctx->req, tfm);
+ ahash_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+ crypto_req_done, &ctx->wait);
+
+ sk->sk_destruct = hash_sock_destruct;
+
+ return 0;
+}
+
+static int hash_accept_parent(void *private, struct sock *sk)
+{
+ struct crypto_ahash *tfm = private;
+
+ if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
+ return -ENOKEY;
+
+ return hash_accept_parent_nokey(private, sk);
+}
+
+static const struct af_alg_type algif_type_hash = {
+ .bind = hash_bind,
+ .release = hash_release,
+ .setkey = hash_setkey,
+ .accept = hash_accept_parent,
+ .accept_nokey = hash_accept_parent_nokey,
+ .ops = &algif_hash_ops,
+ .ops_nokey = &algif_hash_ops_nokey,
+ .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");