crypto: switch af_alg_make_sg() to iov_iter

With that, all ->sendmsg() instances are converted to iov_iter primitives
and are agnostic wrt the kind of iov_iter they are working with.
So's the last remaining ->recvmsg() instance that wasn't kind-agnostic yet.
All ->sendmsg() and ->recvmsg() advance ->msg_iter by the amount actually
copied and none of them modifies the underlying iovec, etc.

Cc: linux-crypto@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2014-11-28 16:39:25 -05:00
parent 31a25fae85
commit 1d10eb2f15
4 changed files with 64 additions and 102 deletions

View file

@ -338,49 +338,31 @@ static const struct net_proto_family alg_family = {
.owner = THIS_MODULE,
};
int af_alg_make_sg(struct af_alg_sgl *sgl, void __user *addr, int len,
int write)
int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len)
{
unsigned long from = (unsigned long)addr;
unsigned long npages;
unsigned off;
int err;
int i;
size_t off;
ssize_t n;
int npages, i;
err = -EFAULT;
if (!access_ok(write ? VERIFY_READ : VERIFY_WRITE, addr, len))
goto out;
n = iov_iter_get_pages(iter, sgl->pages, len, ALG_MAX_PAGES, &off);
if (n < 0)
return n;
off = from & ~PAGE_MASK;
npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
if (npages > ALG_MAX_PAGES)
npages = ALG_MAX_PAGES;
err = get_user_pages_fast(from, npages, write, sgl->pages);
if (err < 0)
goto out;
npages = err;
err = -EINVAL;
npages = PAGE_ALIGN(off + n);
if (WARN_ON(npages == 0))
goto out;
err = 0;
return -EINVAL;
sg_init_table(sgl->sg, npages);
for (i = 0; i < npages; i++) {
for (i = 0, len = n; i < npages; i++) {
int plen = min_t(int, len, PAGE_SIZE - off);
sg_set_page(sgl->sg + i, sgl->pages[i], plen, off);
off = 0;
len -= plen;
err += plen;
}
out:
return err;
return n;
}
EXPORT_SYMBOL_GPL(af_alg_make_sg);

View file

@ -41,8 +41,6 @@ static int hash_sendmsg(struct kiocb *unused, struct socket *sock,
struct sock *sk = sock->sk;
struct alg_sock *ask = alg_sk(sk);
struct hash_ctx *ctx = ask->private;
unsigned long iovlen;
const struct iovec *iov;
long copied = 0;
int err;
@ -58,37 +56,28 @@ static int hash_sendmsg(struct kiocb *unused, struct socket *sock,
ctx->more = 0;
for (iov = msg->msg_iter.iov, iovlen = msg->msg_iter.nr_segs; iovlen > 0;
iovlen--, iov++) {
unsigned long seglen = iov->iov_len;
char __user *from = iov->iov_base;
while (iov_iter_count(&msg->msg_iter)) {
int len = iov_iter_count(&msg->msg_iter);
while (seglen) {
int len = min_t(unsigned long, seglen, limit);
int newlen;
if (len > limit)
len = limit;
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;
len = af_alg_make_sg(&ctx->sgl, &msg->msg_iter, len);
if (len < 0) {
err = copied ? 0 : len;
goto unlock;
}
ahash_request_set_crypt(&ctx->req, ctx->sgl.sg, NULL, len);
err = af_alg_wait_for_completion(crypto_ahash_update(&ctx->req),
&ctx->completion);
af_alg_free_sg(&ctx->sgl);
if (err)
goto unlock;
copied += len;
iov_iter_advance(&msg->msg_iter, len);
}
err = 0;

View file

@ -426,67 +426,59 @@ static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock,
&ctx->req));
struct skcipher_sg_list *sgl;
struct scatterlist *sg;
unsigned long iovlen;
const struct iovec *iov;
int err = -EAGAIN;
int used;
long copied = 0;
lock_sock(sk);
for (iov = msg->msg_iter.iov, iovlen = msg->msg_iter.nr_segs; iovlen > 0;
iovlen--, iov++) {
unsigned long seglen = iov->iov_len;
char __user *from = iov->iov_base;
while (iov_iter_count(&msg->msg_iter)) {
sgl = list_first_entry(&ctx->tsgl,
struct skcipher_sg_list, list);
sg = sgl->sg;
while (seglen) {
sgl = list_first_entry(&ctx->tsgl,
struct skcipher_sg_list, list);
sg = sgl->sg;
while (!sg->length)
sg++;
while (!sg->length)
sg++;
if (!ctx->used) {
err = skcipher_wait_for_data(sk, flags);
if (err)
goto unlock;
}
used = min_t(unsigned long, ctx->used, seglen);
used = af_alg_make_sg(&ctx->rsgl, from, used, 1);
err = used;
if (err < 0)
used = ctx->used;
if (!used) {
err = skcipher_wait_for_data(sk, flags);
if (err)
goto unlock;
}
if (ctx->more || used < ctx->used)
used -= used % bs;
used = min_t(unsigned long, used, iov_iter_count(&msg->msg_iter));
err = -EINVAL;
if (!used)
goto free;
used = af_alg_make_sg(&ctx->rsgl, &msg->msg_iter, used);
err = used;
if (err < 0)
goto unlock;
ablkcipher_request_set_crypt(&ctx->req, sg,
ctx->rsgl.sg, used,
ctx->iv);
if (ctx->more || used < ctx->used)
used -= used % bs;
err = af_alg_wait_for_completion(
err = -EINVAL;
if (!used)
goto free;
ablkcipher_request_set_crypt(&ctx->req, sg,
ctx->rsgl.sg, used,
ctx->iv);
err = af_alg_wait_for_completion(
ctx->enc ?
crypto_ablkcipher_encrypt(&ctx->req) :
crypto_ablkcipher_decrypt(&ctx->req),
&ctx->completion);
free:
af_alg_free_sg(&ctx->rsgl);
af_alg_free_sg(&ctx->rsgl);
if (err)
goto unlock;
if (err)
goto unlock;
copied += used;
from += used;
seglen -= used;
skcipher_pull_sgl(sk, used);
}
copied += used;
skcipher_pull_sgl(sk, used);
iov_iter_advance(&msg->msg_iter, used);
}
err = 0;

View file

@ -67,8 +67,7 @@ int af_alg_unregister_type(const struct af_alg_type *type);
int af_alg_release(struct socket *sock);
int af_alg_accept(struct sock *sk, struct socket *newsock);
int af_alg_make_sg(struct af_alg_sgl *sgl, void __user *addr, int len,
int write);
int af_alg_make_sg(struct af_alg_sgl *sgl, struct iov_iter *iter, int len);
void af_alg_free_sg(struct af_alg_sgl *sgl);
int af_alg_cmsg_send(struct msghdr *msg, struct af_alg_control *con);