Revision 03049269de433cb5fe2859be9ae4469ceb1163ed authored by Michal Hocko on 25 March 2016, 21:20:33 UTC, committed by Linus Torvalds on 25 March 2016, 23:37:42 UTC
wake_oom_reaper has allowed only 1 oom victim to be queued. The main reason for that was the simplicity as other solutions would require some way of queuing. The current approach is racy and that was deemed sufficient as the oom_reaper is considered a best effort approach to help with oom handling when the OOM victim cannot terminate in a reasonable time. The race could lead to missing an oom victim which can get stuck out_of_memory wake_oom_reaper cmpxchg // OK oom_reaper oom_reap_task __oom_reap_task oom_victim terminates atomic_inc_not_zero // fail out_of_memory wake_oom_reaper cmpxchg // fails task_to_reap = NULL This race requires 2 OOM invocations in a short time period which is not very likely but certainly not impossible. E.g. the original victim might have not released a lot of memory for some reason. The situation would improve considerably if wake_oom_reaper used a more robust queuing. This is what this patch implements. This means adding oom_reaper_list list_head into task_struct (eat a hole before embeded thread_struct for that purpose) and a oom_reaper_lock spinlock for queuing synchronization. wake_oom_reaper will then add the task on the queue and oom_reaper will dequeue it. Signed-off-by: Michal Hocko <mhocko@suse.com> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: Andrea Argangeli <andrea@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent bc448e8
algif_skcipher.c
/*
* 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.
*
*/
#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>
struct skcipher_sg_list {
struct list_head list;
int cur;
struct scatterlist sg[0];
};
struct skcipher_tfm {
struct crypto_skcipher *skcipher;
bool has_key;
};
struct skcipher_ctx {
struct list_head tsgl;
struct af_alg_sgl rsgl;
void *iv;
struct af_alg_completion completion;
atomic_t inflight;
size_t used;
unsigned int len;
bool more;
bool merge;
bool enc;
struct skcipher_request req;
};
struct skcipher_async_rsgl {
struct af_alg_sgl sgl;
struct list_head list;
};
struct skcipher_async_req {
struct kiocb *iocb;
struct skcipher_async_rsgl first_sgl;
struct list_head list;
struct scatterlist *tsg;
atomic_t *inflight;
struct skcipher_request req;
};
#define MAX_SGL_ENTS ((4096 - sizeof(struct skcipher_sg_list)) / \
sizeof(struct scatterlist) - 1)
static void skcipher_free_async_sgls(struct skcipher_async_req *sreq)
{
struct skcipher_async_rsgl *rsgl, *tmp;
struct scatterlist *sgl;
struct scatterlist *sg;
int i, n;
list_for_each_entry_safe(rsgl, tmp, &sreq->list, list) {
af_alg_free_sg(&rsgl->sgl);
if (rsgl != &sreq->first_sgl)
kfree(rsgl);
}
sgl = sreq->tsg;
n = sg_nents(sgl);
for_each_sg(sgl, sg, n, i)
put_page(sg_page(sg));
kfree(sreq->tsg);
}
static void skcipher_async_cb(struct crypto_async_request *req, int err)
{
struct skcipher_async_req *sreq = req->data;
struct kiocb *iocb = sreq->iocb;
atomic_dec(sreq->inflight);
skcipher_free_async_sgls(sreq);
kzfree(sreq);
iocb->ki_complete(iocb, err, err);
}
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 int skcipher_alloc_sgl(struct sock *sk)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
struct skcipher_sg_list *sgl;
struct scatterlist *sg = NULL;
sgl = list_entry(ctx->tsgl.prev, struct skcipher_sg_list, list);
if (!list_empty(&ctx->tsgl))
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);
}
return 0;
}
static void skcipher_pull_sgl(struct sock *sk, size_t used, int put)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
struct skcipher_sg_list *sgl;
struct scatterlist *sg;
int i;
while (!list_empty(&ctx->tsgl)) {
sgl = list_first_entry(&ctx->tsgl, struct skcipher_sg_list,
list);
sg = sgl->sg;
for (i = 0; i < sgl->cur; i++) {
size_t plen = min_t(size_t, used, sg[i].length);
if (!sg_page(sg + i))
continue;
sg[i].length -= plen;
sg[i].offset += plen;
used -= plen;
ctx->used -= plen;
if (sg[i].length)
return;
if (put)
put_page(sg_page(sg + i));
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_sgl(struct sock *sk)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
skcipher_pull_sgl(sk, ctx->used, 1);
}
static int skcipher_wait_for_wmem(struct sock *sk, unsigned flags)
{
long timeout;
DEFINE_WAIT(wait);
int err = -ERESTARTSYS;
if (flags & MSG_DONTWAIT)
return -EAGAIN;
sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
for (;;) {
if (signal_pending(current))
break;
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
timeout = MAX_SCHEDULE_TIMEOUT;
if (sk_wait_event(sk, &timeout, skcipher_writable(sk))) {
err = 0;
break;
}
}
finish_wait(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)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
long timeout;
DEFINE_WAIT(wait);
int err = -ERESTARTSYS;
if (flags & MSG_DONTWAIT) {
return -EAGAIN;
}
sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
for (;;) {
if (signal_pending(current))
break;
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
timeout = MAX_SCHEDULE_TIMEOUT;
if (sk_wait_event(sk, &timeout, ctx->used)) {
err = 0;
break;
}
}
finish_wait(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_sg_list *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.prev,
struct skcipher_sg_list, 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_sgl(sk);
if (err)
goto unlock;
sgl = list_entry(ctx->tsgl.prev, struct skcipher_sg_list, 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_sg_list *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_sgl(sk);
if (err)
goto unlock;
ctx->merge = 0;
sgl = list_entry(ctx->tsgl.prev, struct skcipher_sg_list, 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 int skcipher_all_sg_nents(struct skcipher_ctx *ctx)
{
struct skcipher_sg_list *sgl;
struct scatterlist *sg;
int nents = 0;
list_for_each_entry(sgl, &ctx->tsgl, list) {
sg = sgl->sg;
while (!sg->length)
sg++;
nents += sg_nents(sg);
}
return nents;
}
static int skcipher_recvmsg_async(struct socket *sock, struct msghdr *msg,
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;
struct skcipher_sg_list *sgl;
struct scatterlist *sg;
struct skcipher_async_req *sreq;
struct skcipher_request *req;
struct skcipher_async_rsgl *last_rsgl = NULL;
unsigned int txbufs = 0, len = 0, tx_nents;
unsigned int reqsize = crypto_skcipher_reqsize(tfm);
unsigned int ivsize = crypto_skcipher_ivsize(tfm);
int err = -ENOMEM;
bool mark = false;
char *iv;
sreq = kzalloc(sizeof(*sreq) + reqsize + ivsize, GFP_KERNEL);
if (unlikely(!sreq))
goto out;
req = &sreq->req;
iv = (char *)(req + 1) + reqsize;
sreq->iocb = msg->msg_iocb;
INIT_LIST_HEAD(&sreq->list);
sreq->inflight = &ctx->inflight;
lock_sock(sk);
tx_nents = skcipher_all_sg_nents(ctx);
sreq->tsg = kcalloc(tx_nents, sizeof(*sg), GFP_KERNEL);
if (unlikely(!sreq->tsg))
goto unlock;
sg_init_table(sreq->tsg, tx_nents);
memcpy(iv, ctx->iv, ivsize);
skcipher_request_set_tfm(req, tfm);
skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP,
skcipher_async_cb, sreq);
while (iov_iter_count(&msg->msg_iter)) {
struct skcipher_async_rsgl *rsgl;
int used;
if (!ctx->used) {
err = skcipher_wait_for_data(sk, flags);
if (err)
goto free;
}
sgl = list_first_entry(&ctx->tsgl,
struct skcipher_sg_list, list);
sg = sgl->sg;
while (!sg->length)
sg++;
used = min_t(unsigned long, ctx->used,
iov_iter_count(&msg->msg_iter));
used = min_t(unsigned long, used, sg->length);
if (txbufs == tx_nents) {
struct scatterlist *tmp;
int x;
/* Ran out of tx slots in async request
* need to expand */
tmp = kcalloc(tx_nents * 2, sizeof(*tmp),
GFP_KERNEL);
if (!tmp)
goto free;
sg_init_table(tmp, tx_nents * 2);
for (x = 0; x < tx_nents; x++)
sg_set_page(&tmp[x], sg_page(&sreq->tsg[x]),
sreq->tsg[x].length,
sreq->tsg[x].offset);
kfree(sreq->tsg);
sreq->tsg = tmp;
tx_nents *= 2;
mark = true;
}
/* Need to take over the tx sgl from ctx
* to the asynch req - these sgls will be freed later */
sg_set_page(sreq->tsg + txbufs++, sg_page(sg), sg->length,
sg->offset);
if (list_empty(&sreq->list)) {
rsgl = &sreq->first_sgl;
list_add_tail(&rsgl->list, &sreq->list);
} else {
rsgl = kmalloc(sizeof(*rsgl), GFP_KERNEL);
if (!rsgl) {
err = -ENOMEM;
goto free;
}
list_add_tail(&rsgl->list, &sreq->list);
}
used = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, used);
err = used;
if (used < 0)
goto free;
if (last_rsgl)
af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl);
last_rsgl = rsgl;
len += used;
skcipher_pull_sgl(sk, used, 0);
iov_iter_advance(&msg->msg_iter, used);
}
if (mark)
sg_mark_end(sreq->tsg + txbufs - 1);
skcipher_request_set_crypt(req, sreq->tsg, sreq->first_sgl.sgl.sg,
len, iv);
err = ctx->enc ? crypto_skcipher_encrypt(req) :
crypto_skcipher_decrypt(req);
if (err == -EINPROGRESS) {
atomic_inc(&ctx->inflight);
err = -EIOCBQUEUED;
sreq = NULL;
goto unlock;
}
free:
skcipher_free_async_sgls(sreq);
unlock:
skcipher_wmem_wakeup(sk);
release_sock(sk);
kzfree(sreq);
out:
return err;
}
static int skcipher_recvmsg_sync(struct socket *sock, struct msghdr *msg,
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 bs = crypto_skcipher_blocksize(tfm);
struct skcipher_sg_list *sgl;
struct scatterlist *sg;
int err = -EAGAIN;
int used;
long copied = 0;
lock_sock(sk);
while (msg_data_left(msg)) {
if (!ctx->used) {
err = skcipher_wait_for_data(sk, flags);
if (err)
goto unlock;
}
used = min_t(unsigned long, ctx->used, msg_data_left(msg));
used = af_alg_make_sg(&ctx->rsgl, &msg->msg_iter, used);
err = used;
if (err < 0)
goto unlock;
if (ctx->more || used < ctx->used)
used -= used % bs;
err = -EINVAL;
if (!used)
goto free;
sgl = list_first_entry(&ctx->tsgl,
struct skcipher_sg_list, list);
sg = sgl->sg;
while (!sg->length)
sg++;
skcipher_request_set_crypt(&ctx->req, sg, ctx->rsgl.sg, used,
ctx->iv);
err = af_alg_wait_for_completion(
ctx->enc ?
crypto_skcipher_encrypt(&ctx->req) :
crypto_skcipher_decrypt(&ctx->req),
&ctx->completion);
free:
af_alg_free_sg(&ctx->rsgl);
if (err)
goto unlock;
copied += used;
skcipher_pull_sgl(sk, used, 1);
iov_iter_advance(&msg->msg_iter, used);
}
err = 0;
unlock:
skcipher_wmem_wakeup(sk);
release_sock(sk);
return copied ?: err;
}
static int skcipher_recvmsg(struct socket *sock, struct msghdr *msg,
size_t ignored, int flags)
{
return (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) ?
skcipher_recvmsg_async(sock, msg, flags) :
skcipher_recvmsg_sync(sock, msg, flags);
}
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_wait(struct sock *sk)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
int ctr = 0;
while (atomic_read(&ctx->inflight) && ctr++ < 100)
msleep(100);
}
static void skcipher_sock_destruct(struct sock *sk)
{
struct alg_sock *ask = alg_sk(sk);
struct skcipher_ctx *ctx = ask->private;
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(&ctx->req);
if (atomic_read(&ctx->inflight))
skcipher_wait(sk);
skcipher_free_sgl(sk);
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) + crypto_skcipher_reqsize(skcipher);
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);
ctx->len = len;
ctx->used = 0;
ctx->more = 0;
ctx->merge = 0;
ctx->enc = 0;
atomic_set(&ctx->inflight, 0);
af_alg_init_completion(&ctx->completion);
ask->private = ctx;
skcipher_request_set_tfm(&ctx->req, skcipher);
skcipher_request_set_callback(&ctx->req, CRYPTO_TFM_REQ_MAY_SLEEP |
CRYPTO_TFM_REQ_MAY_BACKLOG,
af_alg_complete, &ctx->completion);
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");
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