2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-13 07:44:00 +08:00
linux-next/crypto/algif_skcipher.c

998 lines
22 KiB
C
Raw Normal View History

/*
* algif_skcipher: User-space interface for skcipher algorithms
*
* This file provides the user-space API for symmetric key ciphers.
*
* 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.
*
* 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/sched/signal.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/net.h>
#include <net/sock.h>
struct skcipher_tsgl {
struct list_head list;
int cur;
struct scatterlist sg[0];
};
struct skcipher_rsgl {
struct af_alg_sgl sgl;
struct list_head list;
size_t sg_num_bytes;
};
struct skcipher_async_req {
struct kiocb *iocb;
struct sock *sk;
struct skcipher_rsgl first_sgl;
struct list_head rsgl_list;
struct scatterlist *tsgl;
unsigned int tsgl_entries;
unsigned int areqlen;
struct skcipher_request req;
};
struct skcipher_tfm {
struct crypto_skcipher *skcipher;
bool has_key;
};
struct skcipher_ctx {
struct list_head tsgl_list;
void *iv;
struct af_alg_completion completion;
size_t used;
size_t rcvused;
bool more;
bool merge;
bool enc;
unsigned int len;
};
#define MAX_SGL_ENTS ((4096 - sizeof(struct skcipher_tsgl)) / \
sizeof(struct scatterlist) - 1)
static inline int skcipher_sndbuf(struct sock *sk)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
return max_t(int, max_t(int, sk->sk_sndbuf & PAGE_MASK, PAGE_SIZE) -
ctx->used, 0);
}
static inline bool skcipher_writable(struct sock *sk)
{
return PAGE_SIZE <= skcipher_sndbuf(sk);
}
static inline int skcipher_rcvbuf(struct sock *sk)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
return max_t(int, max_t(int, sk->sk_rcvbuf & PAGE_MASK, PAGE_SIZE) -
ctx->rcvused, 0);
}
static inline bool skcipher_readable(struct sock *sk)
{
return PAGE_SIZE <= skcipher_rcvbuf(sk);
}
static int skcipher_alloc_tsgl(struct sock *sk)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
struct skcipher_tsgl *sgl;
struct scatterlist *sg = NULL;
sgl = list_entry(ctx->tsgl_list.prev, struct skcipher_tsgl, list);
if (!list_empty(&ctx->tsgl_list))
sg = sgl->sg;
if (!sg || sgl->cur >= MAX_SGL_ENTS) {
sgl = sock_kmalloc(sk, sizeof(*sgl) +
sizeof(sgl->sg[0]) * (MAX_SGL_ENTS + 1),
GFP_KERNEL);
if (!sgl)
return -ENOMEM;
sg_init_table(sgl->sg, MAX_SGL_ENTS + 1);
sgl->cur = 0;
if (sg)
sg_chain(sg, MAX_SGL_ENTS + 1, sgl->sg);
list_add_tail(&sgl->list, &ctx->tsgl_list);
}
return 0;
}
static unsigned int skcipher_count_tsgl(struct sock *sk, size_t bytes)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
struct skcipher_tsgl *sgl, *tmp;
unsigned int i;
unsigned int sgl_count = 0;
if (!bytes)
return 0;
list_for_each_entry_safe(sgl, tmp, &ctx->tsgl_list, list) {
struct scatterlist *sg = sgl->sg;
for (i = 0; i < sgl->cur; i++) {
sgl_count++;
if (sg[i].length >= bytes)
return sgl_count;
bytes -= sg[i].length;
}
}
return sgl_count;
}
static void skcipher_pull_tsgl(struct sock *sk, size_t used,
struct scatterlist *dst)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
struct skcipher_tsgl *sgl;
struct scatterlist *sg;
unsigned int i;
while (!list_empty(&ctx->tsgl_list)) {
sgl = list_first_entry(&ctx->tsgl_list, struct skcipher_tsgl,
list);
sg = sgl->sg;
for (i = 0; i < sgl->cur; i++) {
size_t plen = min_t(size_t, used, sg[i].length);
struct page *page = sg_page(sg + i);
if (!page)
continue;
/*
* Assumption: caller created skcipher_count_tsgl(len)
* SG entries in dst.
*/
if (dst)
sg_set_page(dst + i, page, plen, sg[i].offset);
sg[i].length -= plen;
sg[i].offset += plen;
used -= plen;
ctx->used -= plen;
if (sg[i].length)
return;
if (!dst)
put_page(page);
sg_assign_page(sg + i, NULL);
}
list_del(&sgl->list);
sock_kfree_s(sk, sgl, sizeof(*sgl) + sizeof(sgl->sg[0]) *
(MAX_SGL_ENTS + 1));
}
if (!ctx->used)
ctx->merge = 0;
}
static void skcipher_free_areq_sgls(struct skcipher_async_req *areq)
{
struct sock *sk = areq->sk;
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
struct skcipher_rsgl *rsgl, *tmp;
struct scatterlist *tsgl;
struct scatterlist *sg;
unsigned int i;
list_for_each_entry_safe(rsgl, tmp, &areq->rsgl_list, list) {
ctx->rcvused -= rsgl->sg_num_bytes;
af_alg_free_sg(&rsgl->sgl);
list_del(&rsgl->list);
if (rsgl != &areq->first_sgl)
sock_kfree_s(sk, rsgl, sizeof(*rsgl));
}
tsgl = areq->tsgl;
for_each_sg(tsgl, sg, areq->tsgl_entries, i) {
if (!sg_page(sg))
continue;
put_page(sg_page(sg));
}
if (areq->tsgl && areq->tsgl_entries)
sock_kfree_s(sk, tsgl, areq->tsgl_entries * sizeof(*tsgl));
}
static int skcipher_wait_for_wmem(struct sock *sk, unsigned flags)
{
DEFINE_WAIT_FUNC(wait, woken_wake_function);
int err = -ERESTARTSYS;
long timeout;
if (flags & MSG_DONTWAIT)
return -EAGAIN;
sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
add_wait_queue(sk_sleep(sk), &wait);
for (;;) {
if (signal_pending(current))
break;
timeout = MAX_SCHEDULE_TIMEOUT;
if (sk_wait_event(sk, &timeout, skcipher_writable(sk), &wait)) {
err = 0;
break;
}
}
remove_wait_queue(sk_sleep(sk), &wait);
return err;
}
static void skcipher_wmem_wakeup(struct sock *sk)
{
struct socket_wq *wq;
if (!skcipher_writable(sk))
return;
rcu_read_lock();
wq = rcu_dereference(sk->sk_wq);
if (skwq_has_sleeper(wq))
wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
POLLRDNORM |
POLLRDBAND);
sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
rcu_read_unlock();
}
static int skcipher_wait_for_data(struct sock *sk, unsigned flags)
{
DEFINE_WAIT_FUNC(wait, woken_wake_function);
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
long timeout;
int err = -ERESTARTSYS;
if (flags & MSG_DONTWAIT) {
return -EAGAIN;
}
sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
add_wait_queue(sk_sleep(sk), &wait);
for (;;) {
if (signal_pending(current))
break;
timeout = MAX_SCHEDULE_TIMEOUT;
if (sk_wait_event(sk, &timeout, ctx->used, &wait)) {
err = 0;
break;
}
}
remove_wait_queue(sk_sleep(sk), &wait);
sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
return err;
}
static void skcipher_data_wakeup(struct sock *sk)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
struct socket_wq *wq;
if (!ctx->used)
return;
rcu_read_lock();
wq = rcu_dereference(sk->sk_wq);
if (skwq_has_sleeper(wq))
wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
POLLRDNORM |
POLLRDBAND);
sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
rcu_read_unlock();
}
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 skcipher_ctx *ctx = ask->private;
struct skcipher_tfm *skc = pask->private;
struct crypto_skcipher *tfm = skc->skcipher;
unsigned ivsize = crypto_skcipher_ivsize(tfm);
struct skcipher_tsgl *sgl;
struct af_alg_control con = {};
long copied = 0;
bool enc = 0;
bool init = 0;
int err;
int i;
if (msg->msg_controllen) {
err = af_alg_cmsg_send(msg, &con);
if (err)
return err;
init = 1;
switch (con.op) {
case ALG_OP_ENCRYPT:
enc = 1;
break;
case ALG_OP_DECRYPT:
enc = 0;
break;
default:
return -EINVAL;
}
if (con.iv && con.iv->ivlen != ivsize)
return -EINVAL;
}
err = -EINVAL;
lock_sock(sk);
if (!ctx->more && ctx->used)
goto unlock;
if (init) {
ctx->enc = enc;
if (con.iv)
memcpy(ctx->iv, con.iv->iv, ivsize);
}
while (size) {
struct scatterlist *sg;
unsigned long len = size;
size_t plen;
if (ctx->merge) {
sgl = list_entry(ctx->tsgl_list.prev,
struct skcipher_tsgl, list);
sg = sgl->sg + sgl->cur - 1;
len = min_t(unsigned long, len,
PAGE_SIZE - sg->offset - sg->length);
err = memcpy_from_msg(page_address(sg_page(sg)) +
sg->offset + sg->length,
msg, len);
if (err)
goto unlock;
sg->length += len;
ctx->merge = (sg->offset + sg->length) &
(PAGE_SIZE - 1);
ctx->used += len;
copied += len;
size -= len;
continue;
}
if (!skcipher_writable(sk)) {
err = skcipher_wait_for_wmem(sk, msg->msg_flags);
if (err)
goto unlock;
}
len = min_t(unsigned long, len, skcipher_sndbuf(sk));
err = skcipher_alloc_tsgl(sk);
if (err)
goto unlock;
sgl = list_entry(ctx->tsgl_list.prev, struct skcipher_tsgl,
list);
sg = sgl->sg;
if (sgl->cur)
sg_unmark_end(sg + sgl->cur - 1);
do {
i = sgl->cur;
plen = min_t(size_t, len, PAGE_SIZE);
sg_assign_page(sg + i, alloc_page(GFP_KERNEL));
err = -ENOMEM;
if (!sg_page(sg + i))
goto unlock;
err = memcpy_from_msg(page_address(sg_page(sg + i)),
msg, plen);
if (err) {
__free_page(sg_page(sg + i));
sg_assign_page(sg + i, NULL);
goto unlock;
}
sg[i].length = plen;
len -= plen;
ctx->used += plen;
copied += plen;
size -= plen;
sgl->cur++;
} while (len && sgl->cur < MAX_SGL_ENTS);
if (!size)
sg_mark_end(sg + sgl->cur - 1);
ctx->merge = plen & (PAGE_SIZE - 1);
}
err = 0;
ctx->more = msg->msg_flags & MSG_MORE;
unlock:
skcipher_data_wakeup(sk);
release_sock(sk);
return copied ?: err;
}
static ssize_t skcipher_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 skcipher_ctx *ctx = ask->private;
struct skcipher_tsgl *sgl;
int err = -EINVAL;
if (flags & MSG_SENDPAGE_NOTLAST)
flags |= MSG_MORE;
lock_sock(sk);
if (!ctx->more && ctx->used)
goto unlock;
if (!size)
goto done;
if (!skcipher_writable(sk)) {
err = skcipher_wait_for_wmem(sk, flags);
if (err)
goto unlock;
}
err = skcipher_alloc_tsgl(sk);
if (err)
goto unlock;
ctx->merge = 0;
sgl = list_entry(ctx->tsgl_list.prev, struct skcipher_tsgl, list);
if (sgl->cur)
sg_unmark_end(sgl->sg + sgl->cur - 1);
sg_mark_end(sgl->sg + sgl->cur);
get_page(page);
sg_set_page(sgl->sg + sgl->cur, page, size, offset);
sgl->cur++;
ctx->used += size;
done:
ctx->more = flags & MSG_MORE;
unlock:
skcipher_data_wakeup(sk);
release_sock(sk);
return err ?: size;
}
static void skcipher_async_cb(struct crypto_async_request *req, int err)
{
struct skcipher_async_req *areq = req->data;
struct sock *sk = areq->sk;
struct kiocb *iocb = areq->iocb;
unsigned int resultlen;
lock_sock(sk);
/* Buffer size written by crypto operation. */
resultlen = areq->req.cryptlen;
skcipher_free_areq_sgls(areq);
sock_kfree_s(sk, areq, areq->areqlen);
__sock_put(sk);
iocb->ki_complete(iocb, err ? err : resultlen, 0);
release_sock(sk);
}
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 skcipher_ctx *ctx = ask->private;
struct skcipher_tfm *skc = pask->private;
struct crypto_skcipher *tfm = skc->skcipher;
unsigned int bs = crypto_skcipher_blocksize(tfm);
unsigned int areqlen = sizeof(struct skcipher_async_req) +
crypto_skcipher_reqsize(tfm);
struct skcipher_async_req *areq;
struct skcipher_rsgl *last_rsgl = NULL;
int err = 0;
size_t len = 0;
/* Allocate cipher request for current operation. */
areq = sock_kmalloc(sk, areqlen, GFP_KERNEL);
if (unlikely(!areq))
return -ENOMEM;
areq->areqlen = areqlen;
areq->sk = sk;
INIT_LIST_HEAD(&areq->rsgl_list);
areq->tsgl = NULL;
areq->tsgl_entries = 0;
/* convert iovecs of output buffers into RX SGL */
while (msg_data_left(msg)) {
struct skcipher_rsgl *rsgl;
size_t seglen;
/* limit the amount of readable buffers */
if (!skcipher_readable(sk))
break;
if (!ctx->used) {
err = skcipher_wait_for_data(sk, flags);
if (err)
goto free;
}
seglen = min_t(size_t, ctx->used, msg_data_left(msg));
if (list_empty(&areq->rsgl_list)) {
rsgl = &areq->first_sgl;
} else {
rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL);
if (!rsgl) {
err = -ENOMEM;
goto free;
}
}
rsgl->sgl.npages = 0;
list_add_tail(&rsgl->list, &areq->rsgl_list);
/* make one iovec available as scatterlist */
err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen);
if (err < 0)
goto free;
/* chain the new scatterlist with previous one */
if (last_rsgl)
af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl);
last_rsgl = rsgl;
len += err;
ctx->rcvused += err;
rsgl->sg_num_bytes = err;
iov_iter_advance(&msg->msg_iter, err);
}
/* Process only as much RX buffers for which we have TX data */
if (len > ctx->used)
len = ctx->used;
/*
* 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 = skcipher_count_tsgl(sk, len);
if (!areq->tsgl_entries)
areq->tsgl_entries = 1;
areq->tsgl = sock_kmalloc(sk, sizeof(*areq->tsgl) * areq->tsgl_entries,
GFP_KERNEL);
if (!areq->tsgl) {
err = -ENOMEM;
goto free;
}
sg_init_table(areq->tsgl, areq->tsgl_entries);
skcipher_pull_tsgl(sk, len, areq->tsgl);
/* Initialize the crypto operation */
skcipher_request_set_tfm(&areq->req, tfm);
skcipher_request_set_crypt(&areq->req, areq->tsgl,
areq->first_sgl.sgl.sg, len, ctx->iv);
if (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) {
/* AIO operation */
areq->iocb = msg->msg_iocb;
skcipher_request_set_callback(&areq->req,
CRYPTO_TFM_REQ_MAY_SLEEP,
skcipher_async_cb, areq);
err = ctx->enc ? crypto_skcipher_encrypt(&areq->req) :
crypto_skcipher_decrypt(&areq->req);
} else {
/* Synchronous operation */
skcipher_request_set_callback(&areq->req,
CRYPTO_TFM_REQ_MAY_SLEEP |
CRYPTO_TFM_REQ_MAY_BACKLOG,
af_alg_complete,
&ctx->completion);
err = af_alg_wait_for_completion(ctx->enc ?
crypto_skcipher_encrypt(&areq->req) :
crypto_skcipher_decrypt(&areq->req),
&ctx->completion);
}
/* AIO operation in progress */
if (err == -EINPROGRESS) {
sock_hold(sk);
return -EIOCBQUEUED;
}
free:
skcipher_free_areq_sgls(areq);
if (areq)
sock_kfree_s(sk, areq, areqlen);
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.
*/
if (err <= 0) {
if (err == -EIOCBQUEUED)
ret = err;
goto out;
}
ret += err;
}
out:
skcipher_wmem_wakeup(sk);
release_sock(sk);
return ret;
}
static unsigned int skcipher_poll(struct file *file, struct socket *sock,
poll_table *wait)
{
struct sock *sk = sock->sk;
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
unsigned int mask;
sock_poll_wait(file, sk_sleep(sk), wait);
mask = 0;
if (ctx->used)
mask |= POLLIN | POLLRDNORM;
if (skcipher_writable(sk))
mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
return mask;
}
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,
.getsockopt = sock_no_getsockopt,
.mmap = sock_no_mmap,
.bind = sock_no_bind,
.accept = sock_no_accept,
.setsockopt = sock_no_setsockopt,
.release = af_alg_release,
.sendmsg = skcipher_sendmsg,
.sendpage = skcipher_sendpage,
.recvmsg = skcipher_recvmsg,
.poll = skcipher_poll,
};
static int skcipher_check_key(struct socket *sock)
{
int err = 0;
struct sock *psk;
struct alg_sock *pask;
struct skcipher_tfm *tfm;
struct sock *sk = sock->sk;
struct alg_sock *ask = alg_sk(sk);
lock_sock(sk);
if (ask->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 (!tfm->has_key)
goto unlock;
if (!pask->refcnt++)
sock_hold(psk);
ask->refcnt = 1;
sock_put(psk);
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 skcipher_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,
.getsockopt = sock_no_getsockopt,
.mmap = sock_no_mmap,
.bind = sock_no_bind,
.accept = sock_no_accept,
.setsockopt = sock_no_setsockopt,
.release = af_alg_release,
.sendmsg = skcipher_sendmsg_nokey,
.sendpage = skcipher_sendpage_nokey,
.recvmsg = skcipher_recvmsg_nokey,
.poll = skcipher_poll,
};
static void *skcipher_bind(const char *name, u32 type, u32 mask)
{
struct skcipher_tfm *tfm;
struct crypto_skcipher *skcipher;
tfm = kzalloc(sizeof(*tfm), GFP_KERNEL);
if (!tfm)
return ERR_PTR(-ENOMEM);
skcipher = crypto_alloc_skcipher(name, type, mask);
if (IS_ERR(skcipher)) {
kfree(tfm);
return ERR_CAST(skcipher);
}
tfm->skcipher = skcipher;
return tfm;
}
static void skcipher_release(void *private)
{
struct skcipher_tfm *tfm = private;
crypto_free_skcipher(tfm->skcipher);
kfree(tfm);
}
static int skcipher_setkey(void *private, const u8 *key, unsigned int keylen)
{
struct skcipher_tfm *tfm = private;
int err;
err = crypto_skcipher_setkey(tfm->skcipher, key, keylen);
tfm->has_key = !err;
return err;
}
static void skcipher_sock_destruct(struct sock *sk)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
struct sock *psk = ask->parent;
struct alg_sock *pask = alg_sk(psk);
struct skcipher_tfm *skc = pask->private;
struct crypto_skcipher *tfm = skc->skcipher;
skcipher_pull_tsgl(sk, ctx->used, NULL);
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 skcipher_ctx *ctx;
struct alg_sock *ask = alg_sk(sk);
struct skcipher_tfm *tfm = private;
struct crypto_skcipher *skcipher = tfm->skcipher;
unsigned int len = sizeof(*ctx);
ctx = sock_kmalloc(sk, len, GFP_KERNEL);
if (!ctx)
return -ENOMEM;
ctx->iv = sock_kmalloc(sk, crypto_skcipher_ivsize(skcipher),
GFP_KERNEL);
if (!ctx->iv) {
sock_kfree_s(sk, ctx, len);
return -ENOMEM;
}
memset(ctx->iv, 0, crypto_skcipher_ivsize(skcipher));
INIT_LIST_HEAD(&ctx->tsgl_list);
ctx->len = len;
ctx->used = 0;
ctx->rcvused = 0;
ctx->more = 0;
ctx->merge = 0;
ctx->enc = 0;
af_alg_init_completion(&ctx->completion);
ask->private = ctx;
sk->sk_destruct = skcipher_sock_destruct;
return 0;
}
static int skcipher_accept_parent(void *private, struct sock *sk)
{
struct skcipher_tfm *tfm = private;
if (!tfm->has_key && crypto_skcipher_has_setkey(tfm->skcipher))
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");