mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
388 lines
9.6 KiB
388 lines
9.6 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
|
* algif_skcipher: User-space interface for skcipher algorithms |
|
* |
|
* This file provides the user-space API for symmetric key ciphers. |
|
* |
|
* Copyright (c) 2010 Herbert Xu <[email protected]> |
|
* |
|
* The following concept of the memory management is used: |
|
* |
|
* The kernel maintains two SGLs, the TX SGL and the RX SGL. The TX SGL is |
|
* filled by user space with the data submitted via sendpage/sendmsg. Filling |
|
* up the TX SGL does not cause a crypto operation -- the data will only be |
|
* tracked by the kernel. Upon receipt of one recvmsg call, the caller must |
|
* provide a buffer which is tracked with the RX SGL. |
|
* |
|
* During the processing of the recvmsg operation, the cipher request is |
|
* allocated and prepared. As part of the recvmsg operation, the processed |
|
* TX buffers are extracted from the TX SGL into a separate SGL. |
|
* |
|
* After the completion of the crypto operation, the RX SGL and the cipher |
|
* request is released. The extracted TX SGL parts are released together with |
|
* the RX SGL release. |
|
*/ |
|
|
|
#include <crypto/scatterwalk.h> |
|
#include <crypto/skcipher.h> |
|
#include <crypto/if_alg.h> |
|
#include <linux/init.h> |
|
#include <linux/list.h> |
|
#include <linux/kernel.h> |
|
#include <linux/mm.h> |
|
#include <linux/module.h> |
|
#include <linux/net.h> |
|
#include <net/sock.h> |
|
|
|
static int skcipher_sendmsg(struct socket *sock, struct msghdr *msg, |
|
size_t size) |
|
{ |
|
struct sock *sk = sock->sk; |
|
struct alg_sock *ask = alg_sk(sk); |
|
struct sock *psk = ask->parent; |
|
struct alg_sock *pask = alg_sk(psk); |
|
struct crypto_skcipher *tfm = pask->private; |
|
unsigned ivsize = crypto_skcipher_ivsize(tfm); |
|
|
|
return af_alg_sendmsg(sock, msg, size, ivsize); |
|
} |
|
|
|
static int _skcipher_recvmsg(struct socket *sock, struct msghdr *msg, |
|
size_t ignored, int flags) |
|
{ |
|
struct sock *sk = sock->sk; |
|
struct alg_sock *ask = alg_sk(sk); |
|
struct sock *psk = ask->parent; |
|
struct alg_sock *pask = alg_sk(psk); |
|
struct af_alg_ctx *ctx = ask->private; |
|
struct crypto_skcipher *tfm = pask->private; |
|
unsigned int bs = crypto_skcipher_chunksize(tfm); |
|
struct af_alg_async_req *areq; |
|
int err = 0; |
|
size_t len = 0; |
|
|
|
if (!ctx->init || (ctx->more && ctx->used < bs)) { |
|
err = af_alg_wait_for_data(sk, flags, bs); |
|
if (err) |
|
return err; |
|
} |
|
|
|
/* Allocate cipher request for current operation. */ |
|
areq = af_alg_alloc_areq(sk, sizeof(struct af_alg_async_req) + |
|
crypto_skcipher_reqsize(tfm)); |
|
if (IS_ERR(areq)) |
|
return PTR_ERR(areq); |
|
|
|
/* convert iovecs of output buffers into RX SGL */ |
|
err = af_alg_get_rsgl(sk, msg, flags, areq, ctx->used, &len); |
|
if (err) |
|
goto free; |
|
|
|
/* |
|
* If more buffers are to be expected to be processed, process only |
|
* full block size buffers. |
|
*/ |
|
if (ctx->more || len < ctx->used) |
|
len -= len % bs; |
|
|
|
/* |
|
* Create a per request TX SGL for this request which tracks the |
|
* SG entries from the global TX SGL. |
|
*/ |
|
areq->tsgl_entries = af_alg_count_tsgl(sk, len, 0); |
|
if (!areq->tsgl_entries) |
|
areq->tsgl_entries = 1; |
|
areq->tsgl = sock_kmalloc(sk, array_size(sizeof(*areq->tsgl), |
|
areq->tsgl_entries), |
|
GFP_KERNEL); |
|
if (!areq->tsgl) { |
|
err = -ENOMEM; |
|
goto free; |
|
} |
|
sg_init_table(areq->tsgl, areq->tsgl_entries); |
|
af_alg_pull_tsgl(sk, len, areq->tsgl, 0); |
|
|
|
/* Initialize the crypto operation */ |
|
skcipher_request_set_tfm(&areq->cra_u.skcipher_req, tfm); |
|
skcipher_request_set_crypt(&areq->cra_u.skcipher_req, areq->tsgl, |
|
areq->first_rsgl.sgl.sg, len, ctx->iv); |
|
|
|
if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) { |
|
/* AIO operation */ |
|
sock_hold(sk); |
|
areq->iocb = msg->msg_iocb; |
|
|
|
/* Remember output size that will be generated. */ |
|
areq->outlen = len; |
|
|
|
skcipher_request_set_callback(&areq->cra_u.skcipher_req, |
|
CRYPTO_TFM_REQ_MAY_SLEEP, |
|
af_alg_async_cb, areq); |
|
err = ctx->enc ? |
|
crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) : |
|
crypto_skcipher_decrypt(&areq->cra_u.skcipher_req); |
|
|
|
/* AIO operation in progress */ |
|
if (err == -EINPROGRESS) |
|
return -EIOCBQUEUED; |
|
|
|
sock_put(sk); |
|
} else { |
|
/* Synchronous operation */ |
|
skcipher_request_set_callback(&areq->cra_u.skcipher_req, |
|
CRYPTO_TFM_REQ_MAY_SLEEP | |
|
CRYPTO_TFM_REQ_MAY_BACKLOG, |
|
crypto_req_done, &ctx->wait); |
|
err = crypto_wait_req(ctx->enc ? |
|
crypto_skcipher_encrypt(&areq->cra_u.skcipher_req) : |
|
crypto_skcipher_decrypt(&areq->cra_u.skcipher_req), |
|
&ctx->wait); |
|
} |
|
|
|
|
|
free: |
|
af_alg_free_resources(areq); |
|
|
|
return err ? err : len; |
|
} |
|
|
|
static int skcipher_recvmsg(struct socket *sock, struct msghdr *msg, |
|
size_t ignored, int flags) |
|
{ |
|
struct sock *sk = sock->sk; |
|
int ret = 0; |
|
|
|
lock_sock(sk); |
|
while (msg_data_left(msg)) { |
|
int err = _skcipher_recvmsg(sock, msg, ignored, flags); |
|
|
|
/* |
|
* This error covers -EIOCBQUEUED which implies that we can |
|
* only handle one AIO request. If the caller wants to have |
|
* multiple AIO requests in parallel, he must make multiple |
|
* separate AIO calls. |
|
* |
|
* Also return the error if no data has been processed so far. |
|
*/ |
|
if (err <= 0) { |
|
if (err == -EIOCBQUEUED || !ret) |
|
ret = err; |
|
goto out; |
|
} |
|
|
|
ret += err; |
|
} |
|
|
|
out: |
|
af_alg_wmem_wakeup(sk); |
|
release_sock(sk); |
|
return ret; |
|
} |
|
|
|
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, |
|
.sendpage = af_alg_sendpage, |
|
.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 ssize_t skcipher_sendpage_nokey(struct socket *sock, struct page *page, |
|
int offset, size_t size, int flags) |
|
{ |
|
int err; |
|
|
|
err = skcipher_check_key(sock); |
|
if (err) |
|
return err; |
|
|
|
return af_alg_sendpage(sock, page, offset, size, flags); |
|
} |
|
|
|
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, |
|
|
|
.release = af_alg_release, |
|
.sendmsg = skcipher_sendmsg_nokey, |
|
.sendpage = skcipher_sendpage_nokey, |
|
.recvmsg = skcipher_recvmsg_nokey, |
|
.poll = af_alg_poll, |
|
}; |
|
|
|
static void *skcipher_bind(const char *name, u32 type, u32 mask) |
|
{ |
|
return crypto_alloc_skcipher(name, type, mask); |
|
} |
|
|
|
static void skcipher_release(void *private) |
|
{ |
|
crypto_free_skcipher(private); |
|
} |
|
|
|
static int skcipher_setkey(void *private, const u8 *key, unsigned int keylen) |
|
{ |
|
return crypto_skcipher_setkey(private, key, keylen); |
|
} |
|
|
|
static void skcipher_sock_destruct(struct sock *sk) |
|
{ |
|
struct alg_sock *ask = alg_sk(sk); |
|
struct af_alg_ctx *ctx = ask->private; |
|
struct sock *psk = ask->parent; |
|
struct alg_sock *pask = alg_sk(psk); |
|
struct crypto_skcipher *tfm = pask->private; |
|
|
|
af_alg_pull_tsgl(sk, ctx->used, NULL, 0); |
|
sock_kzfree_s(sk, ctx->iv, crypto_skcipher_ivsize(tfm)); |
|
sock_kfree_s(sk, ctx, ctx->len); |
|
af_alg_release_parent(sk); |
|
} |
|
|
|
static int skcipher_accept_parent_nokey(void *private, struct sock *sk) |
|
{ |
|
struct af_alg_ctx *ctx; |
|
struct alg_sock *ask = alg_sk(sk); |
|
struct crypto_skcipher *tfm = private; |
|
unsigned int len = sizeof(*ctx); |
|
|
|
ctx = sock_kmalloc(sk, len, GFP_KERNEL); |
|
if (!ctx) |
|
return -ENOMEM; |
|
memset(ctx, 0, len); |
|
|
|
ctx->iv = sock_kmalloc(sk, crypto_skcipher_ivsize(tfm), |
|
GFP_KERNEL); |
|
if (!ctx->iv) { |
|
sock_kfree_s(sk, ctx, len); |
|
return -ENOMEM; |
|
} |
|
memset(ctx->iv, 0, crypto_skcipher_ivsize(tfm)); |
|
|
|
INIT_LIST_HEAD(&ctx->tsgl_list); |
|
ctx->len = len; |
|
crypto_init_wait(&ctx->wait); |
|
|
|
ask->private = ctx; |
|
|
|
sk->sk_destruct = skcipher_sock_destruct; |
|
|
|
return 0; |
|
} |
|
|
|
static int skcipher_accept_parent(void *private, struct sock *sk) |
|
{ |
|
struct crypto_skcipher *tfm = private; |
|
|
|
if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) |
|
return -ENOKEY; |
|
|
|
return skcipher_accept_parent_nokey(private, sk); |
|
} |
|
|
|
static const struct af_alg_type algif_type_skcipher = { |
|
.bind = skcipher_bind, |
|
.release = skcipher_release, |
|
.setkey = skcipher_setkey, |
|
.accept = skcipher_accept_parent, |
|
.accept_nokey = skcipher_accept_parent_nokey, |
|
.ops = &algif_skcipher_ops, |
|
.ops_nokey = &algif_skcipher_ops_nokey, |
|
.name = "skcipher", |
|
.owner = THIS_MODULE |
|
}; |
|
|
|
static int __init algif_skcipher_init(void) |
|
{ |
|
return af_alg_register_type(&algif_type_skcipher); |
|
} |
|
|
|
static void __exit algif_skcipher_exit(void) |
|
{ |
|
int err = af_alg_unregister_type(&algif_type_skcipher); |
|
BUG_ON(err); |
|
} |
|
|
|
module_init(algif_skcipher_init); |
|
module_exit(algif_skcipher_exit); |
|
MODULE_LICENSE("GPL");
|
|
|