linux_dsm_epyc7002/net/tls/tls_sw.c
Vakul Garg 94524d8fc9 net/tls: Add support for async decryption of tls records
When tls records are decrypted using asynchronous acclerators such as
NXP CAAM engine, the crypto apis return -EINPROGRESS. Presently, on
getting -EINPROGRESS, the tls record processing stops till the time the
crypto accelerator finishes off and returns the result. This incurs a
context switch and is not an efficient way of accessing the crypto
accelerators. Crypto accelerators work efficient when they are queued
with multiple crypto jobs without having to wait for the previous ones
to complete.

The patch submits multiple crypto requests without having to wait for
for previous ones to complete. This has been implemented for records
which are decrypted in zero-copy mode. At the end of recvmsg(), we wait
for all the asynchronous decryption requests to complete.

The references to records which have been sent for async decryption are
dropped. For cases where record decryption is not possible in zero-copy
mode, asynchronous decryption is not used and we wait for decryption
crypto api to complete.

For crypto requests executing in async fashion, the memory for
aead_request, sglists and skb etc is freed from the decryption
completion handler. The decryption completion handler wakesup the
sleeping user context when recvmsg() flags that it has done sending
all the decryption requests and there are no more decryption requests
pending to be completed.

Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Reviewed-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-01 19:52:50 -07:00

1499 lines
37 KiB
C

/*
* Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved.
* Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. All rights reserved.
* Copyright (c) 2016-2017, Lance Chao <lancerchao@fb.com>. All rights reserved.
* Copyright (c) 2016, Fridolin Pokorny <fridolin.pokorny@gmail.com>. All rights reserved.
* Copyright (c) 2016, Nikos Mavrogiannopoulos <nmav@gnutls.org>. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/sched/signal.h>
#include <linux/module.h>
#include <crypto/aead.h>
#include <net/strparser.h>
#include <net/tls.h>
#define MAX_IV_SIZE TLS_CIPHER_AES_GCM_128_IV_SIZE
static int __skb_nsg(struct sk_buff *skb, int offset, int len,
unsigned int recursion_level)
{
int start = skb_headlen(skb);
int i, chunk = start - offset;
struct sk_buff *frag_iter;
int elt = 0;
if (unlikely(recursion_level >= 24))
return -EMSGSIZE;
if (chunk > 0) {
if (chunk > len)
chunk = len;
elt++;
len -= chunk;
if (len == 0)
return elt;
offset += chunk;
}
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
int end;
WARN_ON(start > offset + len);
end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]);
chunk = end - offset;
if (chunk > 0) {
if (chunk > len)
chunk = len;
elt++;
len -= chunk;
if (len == 0)
return elt;
offset += chunk;
}
start = end;
}
if (unlikely(skb_has_frag_list(skb))) {
skb_walk_frags(skb, frag_iter) {
int end, ret;
WARN_ON(start > offset + len);
end = start + frag_iter->len;
chunk = end - offset;
if (chunk > 0) {
if (chunk > len)
chunk = len;
ret = __skb_nsg(frag_iter, offset - start, chunk,
recursion_level + 1);
if (unlikely(ret < 0))
return ret;
elt += ret;
len -= chunk;
if (len == 0)
return elt;
offset += chunk;
}
start = end;
}
}
BUG_ON(len);
return elt;
}
/* Return the number of scatterlist elements required to completely map the
* skb, or -EMSGSIZE if the recursion depth is exceeded.
*/
static int skb_nsg(struct sk_buff *skb, int offset, int len)
{
return __skb_nsg(skb, offset, len, 0);
}
static void tls_decrypt_done(struct crypto_async_request *req, int err)
{
struct aead_request *aead_req = (struct aead_request *)req;
struct decrypt_req_ctx *req_ctx =
(struct decrypt_req_ctx *)(aead_req + 1);
struct scatterlist *sgout = aead_req->dst;
struct tls_context *tls_ctx = tls_get_ctx(req_ctx->sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
int pending = atomic_dec_return(&ctx->decrypt_pending);
struct scatterlist *sg;
unsigned int pages;
/* Propagate if there was an err */
if (err) {
ctx->async_wait.err = err;
tls_err_abort(req_ctx->sk, err);
}
/* Release the skb, pages and memory allocated for crypto req */
kfree_skb(req->data);
/* Skip the first S/G entry as it points to AAD */
for_each_sg(sg_next(sgout), sg, UINT_MAX, pages) {
if (!sg)
break;
put_page(sg_page(sg));
}
kfree(aead_req);
if (!pending && READ_ONCE(ctx->async_notify))
complete(&ctx->async_wait.completion);
}
static int tls_do_decryption(struct sock *sk,
struct sk_buff *skb,
struct scatterlist *sgin,
struct scatterlist *sgout,
char *iv_recv,
size_t data_len,
struct aead_request *aead_req,
bool async)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
int ret;
aead_request_set_tfm(aead_req, ctx->aead_recv);
aead_request_set_ad(aead_req, TLS_AAD_SPACE_SIZE);
aead_request_set_crypt(aead_req, sgin, sgout,
data_len + tls_ctx->rx.tag_size,
(u8 *)iv_recv);
if (async) {
struct decrypt_req_ctx *req_ctx;
req_ctx = (struct decrypt_req_ctx *)(aead_req + 1);
req_ctx->sk = sk;
aead_request_set_callback(aead_req,
CRYPTO_TFM_REQ_MAY_BACKLOG,
tls_decrypt_done, skb);
atomic_inc(&ctx->decrypt_pending);
} else {
aead_request_set_callback(aead_req,
CRYPTO_TFM_REQ_MAY_BACKLOG,
crypto_req_done, &ctx->async_wait);
}
ret = crypto_aead_decrypt(aead_req);
if (ret == -EINPROGRESS) {
if (async)
return ret;
ret = crypto_wait_req(ret, &ctx->async_wait);
}
if (async)
atomic_dec(&ctx->decrypt_pending);
return ret;
}
static void trim_sg(struct sock *sk, struct scatterlist *sg,
int *sg_num_elem, unsigned int *sg_size, int target_size)
{
int i = *sg_num_elem - 1;
int trim = *sg_size - target_size;
if (trim <= 0) {
WARN_ON(trim < 0);
return;
}
*sg_size = target_size;
while (trim >= sg[i].length) {
trim -= sg[i].length;
sk_mem_uncharge(sk, sg[i].length);
put_page(sg_page(&sg[i]));
i--;
if (i < 0)
goto out;
}
sg[i].length -= trim;
sk_mem_uncharge(sk, trim);
out:
*sg_num_elem = i + 1;
}
static void trim_both_sgl(struct sock *sk, int target_size)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
trim_sg(sk, ctx->sg_plaintext_data,
&ctx->sg_plaintext_num_elem,
&ctx->sg_plaintext_size,
target_size);
if (target_size > 0)
target_size += tls_ctx->tx.overhead_size;
trim_sg(sk, ctx->sg_encrypted_data,
&ctx->sg_encrypted_num_elem,
&ctx->sg_encrypted_size,
target_size);
}
static int alloc_encrypted_sg(struct sock *sk, int len)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
int rc = 0;
rc = sk_alloc_sg(sk, len,
ctx->sg_encrypted_data, 0,
&ctx->sg_encrypted_num_elem,
&ctx->sg_encrypted_size, 0);
return rc;
}
static int alloc_plaintext_sg(struct sock *sk, int len)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
int rc = 0;
rc = sk_alloc_sg(sk, len, ctx->sg_plaintext_data, 0,
&ctx->sg_plaintext_num_elem, &ctx->sg_plaintext_size,
tls_ctx->pending_open_record_frags);
return rc;
}
static void free_sg(struct sock *sk, struct scatterlist *sg,
int *sg_num_elem, unsigned int *sg_size)
{
int i, n = *sg_num_elem;
for (i = 0; i < n; ++i) {
sk_mem_uncharge(sk, sg[i].length);
put_page(sg_page(&sg[i]));
}
*sg_num_elem = 0;
*sg_size = 0;
}
static void tls_free_both_sg(struct sock *sk)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
free_sg(sk, ctx->sg_encrypted_data, &ctx->sg_encrypted_num_elem,
&ctx->sg_encrypted_size);
free_sg(sk, ctx->sg_plaintext_data, &ctx->sg_plaintext_num_elem,
&ctx->sg_plaintext_size);
}
static int tls_do_encryption(struct tls_context *tls_ctx,
struct tls_sw_context_tx *ctx,
struct aead_request *aead_req,
size_t data_len)
{
int rc;
ctx->sg_encrypted_data[0].offset += tls_ctx->tx.prepend_size;
ctx->sg_encrypted_data[0].length -= tls_ctx->tx.prepend_size;
aead_request_set_tfm(aead_req, ctx->aead_send);
aead_request_set_ad(aead_req, TLS_AAD_SPACE_SIZE);
aead_request_set_crypt(aead_req, ctx->sg_aead_in, ctx->sg_aead_out,
data_len, tls_ctx->tx.iv);
aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
crypto_req_done, &ctx->async_wait);
rc = crypto_wait_req(crypto_aead_encrypt(aead_req), &ctx->async_wait);
ctx->sg_encrypted_data[0].offset -= tls_ctx->tx.prepend_size;
ctx->sg_encrypted_data[0].length += tls_ctx->tx.prepend_size;
return rc;
}
static int tls_push_record(struct sock *sk, int flags,
unsigned char record_type)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
struct aead_request *req;
int rc;
req = aead_request_alloc(ctx->aead_send, sk->sk_allocation);
if (!req)
return -ENOMEM;
sg_mark_end(ctx->sg_plaintext_data + ctx->sg_plaintext_num_elem - 1);
sg_mark_end(ctx->sg_encrypted_data + ctx->sg_encrypted_num_elem - 1);
tls_make_aad(ctx->aad_space, ctx->sg_plaintext_size,
tls_ctx->tx.rec_seq, tls_ctx->tx.rec_seq_size,
record_type);
tls_fill_prepend(tls_ctx,
page_address(sg_page(&ctx->sg_encrypted_data[0])) +
ctx->sg_encrypted_data[0].offset,
ctx->sg_plaintext_size, record_type);
tls_ctx->pending_open_record_frags = 0;
set_bit(TLS_PENDING_CLOSED_RECORD, &tls_ctx->flags);
rc = tls_do_encryption(tls_ctx, ctx, req, ctx->sg_plaintext_size);
if (rc < 0) {
/* If we are called from write_space and
* we fail, we need to set this SOCK_NOSPACE
* to trigger another write_space in the future.
*/
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
goto out_req;
}
free_sg(sk, ctx->sg_plaintext_data, &ctx->sg_plaintext_num_elem,
&ctx->sg_plaintext_size);
ctx->sg_encrypted_num_elem = 0;
ctx->sg_encrypted_size = 0;
/* Only pass through MSG_DONTWAIT and MSG_NOSIGNAL flags */
rc = tls_push_sg(sk, tls_ctx, ctx->sg_encrypted_data, 0, flags);
if (rc < 0 && rc != -EAGAIN)
tls_err_abort(sk, EBADMSG);
tls_advance_record_sn(sk, &tls_ctx->tx);
out_req:
aead_request_free(req);
return rc;
}
static int tls_sw_push_pending_record(struct sock *sk, int flags)
{
return tls_push_record(sk, flags, TLS_RECORD_TYPE_DATA);
}
static int zerocopy_from_iter(struct sock *sk, struct iov_iter *from,
int length, int *pages_used,
unsigned int *size_used,
struct scatterlist *to, int to_max_pages,
bool charge)
{
struct page *pages[MAX_SKB_FRAGS];
size_t offset;
ssize_t copied, use;
int i = 0;
unsigned int size = *size_used;
int num_elem = *pages_used;
int rc = 0;
int maxpages;
while (length > 0) {
i = 0;
maxpages = to_max_pages - num_elem;
if (maxpages == 0) {
rc = -EFAULT;
goto out;
}
copied = iov_iter_get_pages(from, pages,
length,
maxpages, &offset);
if (copied <= 0) {
rc = -EFAULT;
goto out;
}
iov_iter_advance(from, copied);
length -= copied;
size += copied;
while (copied) {
use = min_t(int, copied, PAGE_SIZE - offset);
sg_set_page(&to[num_elem],
pages[i], use, offset);
sg_unmark_end(&to[num_elem]);
if (charge)
sk_mem_charge(sk, use);
offset = 0;
copied -= use;
++i;
++num_elem;
}
}
/* Mark the end in the last sg entry if newly added */
if (num_elem > *pages_used)
sg_mark_end(&to[num_elem - 1]);
out:
if (rc)
iov_iter_revert(from, size - *size_used);
*size_used = size;
*pages_used = num_elem;
return rc;
}
static int memcopy_from_iter(struct sock *sk, struct iov_iter *from,
int bytes)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
struct scatterlist *sg = ctx->sg_plaintext_data;
int copy, i, rc = 0;
for (i = tls_ctx->pending_open_record_frags;
i < ctx->sg_plaintext_num_elem; ++i) {
copy = sg[i].length;
if (copy_from_iter(
page_address(sg_page(&sg[i])) + sg[i].offset,
copy, from) != copy) {
rc = -EFAULT;
goto out;
}
bytes -= copy;
++tls_ctx->pending_open_record_frags;
if (!bytes)
break;
}
out:
return rc;
}
int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
int ret = 0;
int required_size;
long timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
bool eor = !(msg->msg_flags & MSG_MORE);
size_t try_to_copy, copied = 0;
unsigned char record_type = TLS_RECORD_TYPE_DATA;
int record_room;
bool full_record;
int orig_size;
bool is_kvec = msg->msg_iter.type & ITER_KVEC;
if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL))
return -ENOTSUPP;
lock_sock(sk);
if (tls_complete_pending_work(sk, tls_ctx, msg->msg_flags, &timeo))
goto send_end;
if (unlikely(msg->msg_controllen)) {
ret = tls_proccess_cmsg(sk, msg, &record_type);
if (ret)
goto send_end;
}
while (msg_data_left(msg)) {
if (sk->sk_err) {
ret = -sk->sk_err;
goto send_end;
}
orig_size = ctx->sg_plaintext_size;
full_record = false;
try_to_copy = msg_data_left(msg);
record_room = TLS_MAX_PAYLOAD_SIZE - ctx->sg_plaintext_size;
if (try_to_copy >= record_room) {
try_to_copy = record_room;
full_record = true;
}
required_size = ctx->sg_plaintext_size + try_to_copy +
tls_ctx->tx.overhead_size;
if (!sk_stream_memory_free(sk))
goto wait_for_sndbuf;
alloc_encrypted:
ret = alloc_encrypted_sg(sk, required_size);
if (ret) {
if (ret != -ENOSPC)
goto wait_for_memory;
/* Adjust try_to_copy according to the amount that was
* actually allocated. The difference is due
* to max sg elements limit
*/
try_to_copy -= required_size - ctx->sg_encrypted_size;
full_record = true;
}
if (!is_kvec && (full_record || eor)) {
ret = zerocopy_from_iter(sk, &msg->msg_iter,
try_to_copy, &ctx->sg_plaintext_num_elem,
&ctx->sg_plaintext_size,
ctx->sg_plaintext_data,
ARRAY_SIZE(ctx->sg_plaintext_data),
true);
if (ret)
goto fallback_to_reg_send;
copied += try_to_copy;
ret = tls_push_record(sk, msg->msg_flags, record_type);
if (ret)
goto send_end;
continue;
fallback_to_reg_send:
trim_sg(sk, ctx->sg_plaintext_data,
&ctx->sg_plaintext_num_elem,
&ctx->sg_plaintext_size,
orig_size);
}
required_size = ctx->sg_plaintext_size + try_to_copy;
alloc_plaintext:
ret = alloc_plaintext_sg(sk, required_size);
if (ret) {
if (ret != -ENOSPC)
goto wait_for_memory;
/* Adjust try_to_copy according to the amount that was
* actually allocated. The difference is due
* to max sg elements limit
*/
try_to_copy -= required_size - ctx->sg_plaintext_size;
full_record = true;
trim_sg(sk, ctx->sg_encrypted_data,
&ctx->sg_encrypted_num_elem,
&ctx->sg_encrypted_size,
ctx->sg_plaintext_size +
tls_ctx->tx.overhead_size);
}
ret = memcopy_from_iter(sk, &msg->msg_iter, try_to_copy);
if (ret)
goto trim_sgl;
copied += try_to_copy;
if (full_record || eor) {
push_record:
ret = tls_push_record(sk, msg->msg_flags, record_type);
if (ret) {
if (ret == -ENOMEM)
goto wait_for_memory;
goto send_end;
}
}
continue;
wait_for_sndbuf:
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
wait_for_memory:
ret = sk_stream_wait_memory(sk, &timeo);
if (ret) {
trim_sgl:
trim_both_sgl(sk, orig_size);
goto send_end;
}
if (tls_is_pending_closed_record(tls_ctx))
goto push_record;
if (ctx->sg_encrypted_size < required_size)
goto alloc_encrypted;
goto alloc_plaintext;
}
send_end:
ret = sk_stream_error(sk, msg->msg_flags, ret);
release_sock(sk);
return copied ? copied : ret;
}
int tls_sw_sendpage(struct sock *sk, struct page *page,
int offset, size_t size, int flags)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
int ret = 0;
long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
bool eor;
size_t orig_size = size;
unsigned char record_type = TLS_RECORD_TYPE_DATA;
struct scatterlist *sg;
bool full_record;
int record_room;
if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
MSG_SENDPAGE_NOTLAST))
return -ENOTSUPP;
/* No MSG_EOR from splice, only look at MSG_MORE */
eor = !(flags & (MSG_MORE | MSG_SENDPAGE_NOTLAST));
lock_sock(sk);
sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
if (tls_complete_pending_work(sk, tls_ctx, flags, &timeo))
goto sendpage_end;
/* Call the sk_stream functions to manage the sndbuf mem. */
while (size > 0) {
size_t copy, required_size;
if (sk->sk_err) {
ret = -sk->sk_err;
goto sendpage_end;
}
full_record = false;
record_room = TLS_MAX_PAYLOAD_SIZE - ctx->sg_plaintext_size;
copy = size;
if (copy >= record_room) {
copy = record_room;
full_record = true;
}
required_size = ctx->sg_plaintext_size + copy +
tls_ctx->tx.overhead_size;
if (!sk_stream_memory_free(sk))
goto wait_for_sndbuf;
alloc_payload:
ret = alloc_encrypted_sg(sk, required_size);
if (ret) {
if (ret != -ENOSPC)
goto wait_for_memory;
/* Adjust copy according to the amount that was
* actually allocated. The difference is due
* to max sg elements limit
*/
copy -= required_size - ctx->sg_plaintext_size;
full_record = true;
}
get_page(page);
sg = ctx->sg_plaintext_data + ctx->sg_plaintext_num_elem;
sg_set_page(sg, page, copy, offset);
sg_unmark_end(sg);
ctx->sg_plaintext_num_elem++;
sk_mem_charge(sk, copy);
offset += copy;
size -= copy;
ctx->sg_plaintext_size += copy;
tls_ctx->pending_open_record_frags = ctx->sg_plaintext_num_elem;
if (full_record || eor ||
ctx->sg_plaintext_num_elem ==
ARRAY_SIZE(ctx->sg_plaintext_data)) {
push_record:
ret = tls_push_record(sk, flags, record_type);
if (ret) {
if (ret == -ENOMEM)
goto wait_for_memory;
goto sendpage_end;
}
}
continue;
wait_for_sndbuf:
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
wait_for_memory:
ret = sk_stream_wait_memory(sk, &timeo);
if (ret) {
trim_both_sgl(sk, ctx->sg_plaintext_size);
goto sendpage_end;
}
if (tls_is_pending_closed_record(tls_ctx))
goto push_record;
goto alloc_payload;
}
sendpage_end:
if (orig_size > size)
ret = orig_size - size;
else
ret = sk_stream_error(sk, flags, ret);
release_sock(sk);
return ret;
}
static struct sk_buff *tls_wait_data(struct sock *sk, int flags,
long timeo, int *err)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
struct sk_buff *skb;
DEFINE_WAIT_FUNC(wait, woken_wake_function);
while (!(skb = ctx->recv_pkt)) {
if (sk->sk_err) {
*err = sock_error(sk);
return NULL;
}
if (sk->sk_shutdown & RCV_SHUTDOWN)
return NULL;
if (sock_flag(sk, SOCK_DONE))
return NULL;
if ((flags & MSG_DONTWAIT) || !timeo) {
*err = -EAGAIN;
return NULL;
}
add_wait_queue(sk_sleep(sk), &wait);
sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
sk_wait_event(sk, &timeo, ctx->recv_pkt != skb, &wait);
sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
remove_wait_queue(sk_sleep(sk), &wait);
/* Handle signals */
if (signal_pending(current)) {
*err = sock_intr_errno(timeo);
return NULL;
}
}
return skb;
}
/* This function decrypts the input skb into either out_iov or in out_sg
* or in skb buffers itself. The input parameter 'zc' indicates if
* zero-copy mode needs to be tried or not. With zero-copy mode, either
* out_iov or out_sg must be non-NULL. In case both out_iov and out_sg are
* NULL, then the decryption happens inside skb buffers itself, i.e.
* zero-copy gets disabled and 'zc' is updated.
*/
static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
struct iov_iter *out_iov,
struct scatterlist *out_sg,
int *chunk, bool *zc)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
struct strp_msg *rxm = strp_msg(skb);
int n_sgin, n_sgout, nsg, mem_size, aead_size, err, pages = 0;
struct aead_request *aead_req;
struct sk_buff *unused;
u8 *aad, *iv, *mem = NULL;
struct scatterlist *sgin = NULL;
struct scatterlist *sgout = NULL;
const int data_len = rxm->full_len - tls_ctx->rx.overhead_size;
if (*zc && (out_iov || out_sg)) {
if (out_iov)
n_sgout = iov_iter_npages(out_iov, INT_MAX) + 1;
else
n_sgout = sg_nents(out_sg);
n_sgin = skb_nsg(skb, rxm->offset + tls_ctx->rx.prepend_size,
rxm->full_len - tls_ctx->rx.prepend_size);
} else {
n_sgout = 0;
*zc = false;
n_sgin = skb_cow_data(skb, 0, &unused);
}
if (n_sgin < 1)
return -EBADMSG;
/* Increment to accommodate AAD */
n_sgin = n_sgin + 1;
nsg = n_sgin + n_sgout;
aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv);
mem_size = aead_size + (nsg * sizeof(struct scatterlist));
mem_size = mem_size + TLS_AAD_SPACE_SIZE;
mem_size = mem_size + crypto_aead_ivsize(ctx->aead_recv);
/* Allocate a single block of memory which contains
* aead_req || sgin[] || sgout[] || aad || iv.
* This order achieves correct alignment for aead_req, sgin, sgout.
*/
mem = kmalloc(mem_size, sk->sk_allocation);
if (!mem)
return -ENOMEM;
/* Segment the allocated memory */
aead_req = (struct aead_request *)mem;
sgin = (struct scatterlist *)(mem + aead_size);
sgout = sgin + n_sgin;
aad = (u8 *)(sgout + n_sgout);
iv = aad + TLS_AAD_SPACE_SIZE;
/* Prepare IV */
err = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE,
iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
tls_ctx->rx.iv_size);
if (err < 0) {
kfree(mem);
return err;
}
memcpy(iv, tls_ctx->rx.iv, TLS_CIPHER_AES_GCM_128_SALT_SIZE);
/* Prepare AAD */
tls_make_aad(aad, rxm->full_len - tls_ctx->rx.overhead_size,
tls_ctx->rx.rec_seq, tls_ctx->rx.rec_seq_size,
ctx->control);
/* Prepare sgin */
sg_init_table(sgin, n_sgin);
sg_set_buf(&sgin[0], aad, TLS_AAD_SPACE_SIZE);
err = skb_to_sgvec(skb, &sgin[1],
rxm->offset + tls_ctx->rx.prepend_size,
rxm->full_len - tls_ctx->rx.prepend_size);
if (err < 0) {
kfree(mem);
return err;
}
if (n_sgout) {
if (out_iov) {
sg_init_table(sgout, n_sgout);
sg_set_buf(&sgout[0], aad, TLS_AAD_SPACE_SIZE);
*chunk = 0;
err = zerocopy_from_iter(sk, out_iov, data_len, &pages,
chunk, &sgout[1],
(n_sgout - 1), false);
if (err < 0)
goto fallback_to_reg_recv;
} else if (out_sg) {
memcpy(sgout, out_sg, n_sgout * sizeof(*sgout));
} else {
goto fallback_to_reg_recv;
}
} else {
fallback_to_reg_recv:
sgout = sgin;
pages = 0;
*chunk = 0;
*zc = false;
}
/* Prepare and submit AEAD request */
err = tls_do_decryption(sk, skb, sgin, sgout, iv,
data_len, aead_req, *zc);
if (err == -EINPROGRESS)
return err;
/* Release the pages in case iov was mapped to pages */
for (; pages > 0; pages--)
put_page(sg_page(&sgout[pages]));
kfree(mem);
return err;
}
static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb,
struct iov_iter *dest, int *chunk, bool *zc)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
struct strp_msg *rxm = strp_msg(skb);
int err = 0;
#ifdef CONFIG_TLS_DEVICE
err = tls_device_decrypted(sk, skb);
if (err < 0)
return err;
#endif
if (!ctx->decrypted) {
err = decrypt_internal(sk, skb, dest, NULL, chunk, zc);
if (err < 0) {
if (err == -EINPROGRESS)
tls_advance_record_sn(sk, &tls_ctx->rx);
return err;
}
} else {
*zc = false;
}
rxm->offset += tls_ctx->rx.prepend_size;
rxm->full_len -= tls_ctx->rx.overhead_size;
tls_advance_record_sn(sk, &tls_ctx->rx);
ctx->decrypted = true;
ctx->saved_data_ready(sk);
return err;
}
int decrypt_skb(struct sock *sk, struct sk_buff *skb,
struct scatterlist *sgout)
{
bool zc = true;
int chunk;
return decrypt_internal(sk, skb, NULL, sgout, &chunk, &zc);
}
static bool tls_sw_advance_skb(struct sock *sk, struct sk_buff *skb,
unsigned int len)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
if (skb) {
struct strp_msg *rxm = strp_msg(skb);
if (len < rxm->full_len) {
rxm->offset += len;
rxm->full_len -= len;
return false;
}
kfree_skb(skb);
}
/* Finished with message */
ctx->recv_pkt = NULL;
__strp_unpause(&ctx->strp);
return true;
}
int tls_sw_recvmsg(struct sock *sk,
struct msghdr *msg,
size_t len,
int nonblock,
int flags,
int *addr_len)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
unsigned char control;
struct strp_msg *rxm;
struct sk_buff *skb;
ssize_t copied = 0;
bool cmsg = false;
int target, err = 0;
long timeo;
bool is_kvec = msg->msg_iter.type & ITER_KVEC;
int num_async = 0;
flags |= nonblock;
if (unlikely(flags & MSG_ERRQUEUE))
return sock_recv_errqueue(sk, msg, len, SOL_IP, IP_RECVERR);
lock_sock(sk);
target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
do {
bool zc = false;
bool async = false;
int chunk = 0;
skb = tls_wait_data(sk, flags, timeo, &err);
if (!skb)
goto recv_end;
rxm = strp_msg(skb);
if (!cmsg) {
int cerr;
cerr = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE,
sizeof(ctx->control), &ctx->control);
cmsg = true;
control = ctx->control;
if (ctx->control != TLS_RECORD_TYPE_DATA) {
if (cerr || msg->msg_flags & MSG_CTRUNC) {
err = -EIO;
goto recv_end;
}
}
} else if (control != ctx->control) {
goto recv_end;
}
if (!ctx->decrypted) {
int to_copy = rxm->full_len - tls_ctx->rx.overhead_size;
if (!is_kvec && to_copy <= len &&
likely(!(flags & MSG_PEEK)))
zc = true;
err = decrypt_skb_update(sk, skb, &msg->msg_iter,
&chunk, &zc);
if (err < 0 && err != -EINPROGRESS) {
tls_err_abort(sk, EBADMSG);
goto recv_end;
}
if (err == -EINPROGRESS) {
async = true;
num_async++;
goto pick_next_record;
}
ctx->decrypted = true;
}
if (!zc) {
chunk = min_t(unsigned int, rxm->full_len, len);
err = skb_copy_datagram_msg(skb, rxm->offset, msg,
chunk);
if (err < 0)
goto recv_end;
}
pick_next_record:
copied += chunk;
len -= chunk;
if (likely(!(flags & MSG_PEEK))) {
u8 control = ctx->control;
/* For async, drop current skb reference */
if (async)
skb = NULL;
if (tls_sw_advance_skb(sk, skb, chunk)) {
/* Return full control message to
* userspace before trying to parse
* another message type
*/
msg->msg_flags |= MSG_EOR;
if (control != TLS_RECORD_TYPE_DATA)
goto recv_end;
} else {
break;
}
}
/* If we have a new message from strparser, continue now. */
if (copied >= target && !ctx->recv_pkt)
break;
} while (len);
recv_end:
if (num_async) {
/* Wait for all previously submitted records to be decrypted */
smp_store_mb(ctx->async_notify, true);
if (atomic_read(&ctx->decrypt_pending)) {
err = crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
if (err) {
/* one of async decrypt failed */
tls_err_abort(sk, err);
copied = 0;
}
} else {
reinit_completion(&ctx->async_wait.completion);
}
WRITE_ONCE(ctx->async_notify, false);
}
release_sock(sk);
return copied ? : err;
}
ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos,
struct pipe_inode_info *pipe,
size_t len, unsigned int flags)
{
struct tls_context *tls_ctx = tls_get_ctx(sock->sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
struct strp_msg *rxm = NULL;
struct sock *sk = sock->sk;
struct sk_buff *skb;
ssize_t copied = 0;
int err = 0;
long timeo;
int chunk;
bool zc = false;
lock_sock(sk);
timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
skb = tls_wait_data(sk, flags, timeo, &err);
if (!skb)
goto splice_read_end;
/* splice does not support reading control messages */
if (ctx->control != TLS_RECORD_TYPE_DATA) {
err = -ENOTSUPP;
goto splice_read_end;
}
if (!ctx->decrypted) {
err = decrypt_skb_update(sk, skb, NULL, &chunk, &zc);
if (err < 0) {
tls_err_abort(sk, EBADMSG);
goto splice_read_end;
}
ctx->decrypted = true;
}
rxm = strp_msg(skb);
chunk = min_t(unsigned int, rxm->full_len, len);
copied = skb_splice_bits(skb, sk, rxm->offset, pipe, chunk, flags);
if (copied < 0)
goto splice_read_end;
if (likely(!(flags & MSG_PEEK)))
tls_sw_advance_skb(sk, skb, copied);
splice_read_end:
release_sock(sk);
return copied ? : err;
}
unsigned int tls_sw_poll(struct file *file, struct socket *sock,
struct poll_table_struct *wait)
{
unsigned int ret;
struct sock *sk = sock->sk;
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
/* Grab POLLOUT and POLLHUP from the underlying socket */
ret = ctx->sk_poll(file, sock, wait);
/* Clear POLLIN bits, and set based on recv_pkt */
ret &= ~(POLLIN | POLLRDNORM);
if (ctx->recv_pkt)
ret |= POLLIN | POLLRDNORM;
return ret;
}
static int tls_read_size(struct strparser *strp, struct sk_buff *skb)
{
struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
char header[TLS_HEADER_SIZE + MAX_IV_SIZE];
struct strp_msg *rxm = strp_msg(skb);
size_t cipher_overhead;
size_t data_len = 0;
int ret;
/* Verify that we have a full TLS header, or wait for more data */
if (rxm->offset + tls_ctx->rx.prepend_size > skb->len)
return 0;
/* Sanity-check size of on-stack buffer. */
if (WARN_ON(tls_ctx->rx.prepend_size > sizeof(header))) {
ret = -EINVAL;
goto read_failure;
}
/* Linearize header to local buffer */
ret = skb_copy_bits(skb, rxm->offset, header, tls_ctx->rx.prepend_size);
if (ret < 0)
goto read_failure;
ctx->control = header[0];
data_len = ((header[4] & 0xFF) | (header[3] << 8));
cipher_overhead = tls_ctx->rx.tag_size + tls_ctx->rx.iv_size;
if (data_len > TLS_MAX_PAYLOAD_SIZE + cipher_overhead) {
ret = -EMSGSIZE;
goto read_failure;
}
if (data_len < cipher_overhead) {
ret = -EBADMSG;
goto read_failure;
}
if (header[1] != TLS_VERSION_MINOR(tls_ctx->crypto_recv.version) ||
header[2] != TLS_VERSION_MAJOR(tls_ctx->crypto_recv.version)) {
ret = -EINVAL;
goto read_failure;
}
#ifdef CONFIG_TLS_DEVICE
handle_device_resync(strp->sk, TCP_SKB_CB(skb)->seq + rxm->offset,
*(u64*)tls_ctx->rx.rec_seq);
#endif
return data_len + TLS_HEADER_SIZE;
read_failure:
tls_err_abort(strp->sk, ret);
return ret;
}
static void tls_queue(struct strparser *strp, struct sk_buff *skb)
{
struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
ctx->decrypted = false;
ctx->recv_pkt = skb;
strp_pause(strp);
ctx->saved_data_ready(strp->sk);
}
static void tls_data_ready(struct sock *sk)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
strp_data_ready(&ctx->strp);
}
void tls_sw_free_resources_tx(struct sock *sk)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
crypto_free_aead(ctx->aead_send);
tls_free_both_sg(sk);
kfree(ctx);
}
void tls_sw_release_resources_rx(struct sock *sk)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
if (ctx->aead_recv) {
kfree_skb(ctx->recv_pkt);
ctx->recv_pkt = NULL;
crypto_free_aead(ctx->aead_recv);
strp_stop(&ctx->strp);
write_lock_bh(&sk->sk_callback_lock);
sk->sk_data_ready = ctx->saved_data_ready;
write_unlock_bh(&sk->sk_callback_lock);
release_sock(sk);
strp_done(&ctx->strp);
lock_sock(sk);
}
}
void tls_sw_free_resources_rx(struct sock *sk)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
tls_sw_release_resources_rx(sk);
kfree(ctx);
}
int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx)
{
char keyval[TLS_CIPHER_AES_GCM_128_KEY_SIZE];
struct tls_crypto_info *crypto_info;
struct tls12_crypto_info_aes_gcm_128 *gcm_128_info;
struct tls_sw_context_tx *sw_ctx_tx = NULL;
struct tls_sw_context_rx *sw_ctx_rx = NULL;
struct cipher_context *cctx;
struct crypto_aead **aead;
struct strp_callbacks cb;
u16 nonce_size, tag_size, iv_size, rec_seq_size;
char *iv, *rec_seq;
int rc = 0;
if (!ctx) {
rc = -EINVAL;
goto out;
}
if (tx) {
if (!ctx->priv_ctx_tx) {
sw_ctx_tx = kzalloc(sizeof(*sw_ctx_tx), GFP_KERNEL);
if (!sw_ctx_tx) {
rc = -ENOMEM;
goto out;
}
ctx->priv_ctx_tx = sw_ctx_tx;
} else {
sw_ctx_tx =
(struct tls_sw_context_tx *)ctx->priv_ctx_tx;
}
} else {
if (!ctx->priv_ctx_rx) {
sw_ctx_rx = kzalloc(sizeof(*sw_ctx_rx), GFP_KERNEL);
if (!sw_ctx_rx) {
rc = -ENOMEM;
goto out;
}
ctx->priv_ctx_rx = sw_ctx_rx;
} else {
sw_ctx_rx =
(struct tls_sw_context_rx *)ctx->priv_ctx_rx;
}
}
if (tx) {
crypto_init_wait(&sw_ctx_tx->async_wait);
crypto_info = &ctx->crypto_send;
cctx = &ctx->tx;
aead = &sw_ctx_tx->aead_send;
} else {
crypto_init_wait(&sw_ctx_rx->async_wait);
crypto_info = &ctx->crypto_recv;
cctx = &ctx->rx;
aead = &sw_ctx_rx->aead_recv;
}
switch (crypto_info->cipher_type) {
case TLS_CIPHER_AES_GCM_128: {
nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
rec_seq =
((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
gcm_128_info =
(struct tls12_crypto_info_aes_gcm_128 *)crypto_info;
break;
}
default:
rc = -EINVAL;
goto free_priv;
}
/* Sanity-check the IV size for stack allocations. */
if (iv_size > MAX_IV_SIZE || nonce_size > MAX_IV_SIZE) {
rc = -EINVAL;
goto free_priv;
}
cctx->prepend_size = TLS_HEADER_SIZE + nonce_size;
cctx->tag_size = tag_size;
cctx->overhead_size = cctx->prepend_size + cctx->tag_size;
cctx->iv_size = iv_size;
cctx->iv = kmalloc(iv_size + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
GFP_KERNEL);
if (!cctx->iv) {
rc = -ENOMEM;
goto free_priv;
}
memcpy(cctx->iv, gcm_128_info->salt, TLS_CIPHER_AES_GCM_128_SALT_SIZE);
memcpy(cctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv, iv_size);
cctx->rec_seq_size = rec_seq_size;
cctx->rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
if (!cctx->rec_seq) {
rc = -ENOMEM;
goto free_iv;
}
if (sw_ctx_tx) {
sg_init_table(sw_ctx_tx->sg_encrypted_data,
ARRAY_SIZE(sw_ctx_tx->sg_encrypted_data));
sg_init_table(sw_ctx_tx->sg_plaintext_data,
ARRAY_SIZE(sw_ctx_tx->sg_plaintext_data));
sg_init_table(sw_ctx_tx->sg_aead_in, 2);
sg_set_buf(&sw_ctx_tx->sg_aead_in[0], sw_ctx_tx->aad_space,
sizeof(sw_ctx_tx->aad_space));
sg_unmark_end(&sw_ctx_tx->sg_aead_in[1]);
sg_chain(sw_ctx_tx->sg_aead_in, 2,
sw_ctx_tx->sg_plaintext_data);
sg_init_table(sw_ctx_tx->sg_aead_out, 2);
sg_set_buf(&sw_ctx_tx->sg_aead_out[0], sw_ctx_tx->aad_space,
sizeof(sw_ctx_tx->aad_space));
sg_unmark_end(&sw_ctx_tx->sg_aead_out[1]);
sg_chain(sw_ctx_tx->sg_aead_out, 2,
sw_ctx_tx->sg_encrypted_data);
}
if (!*aead) {
*aead = crypto_alloc_aead("gcm(aes)", 0, 0);
if (IS_ERR(*aead)) {
rc = PTR_ERR(*aead);
*aead = NULL;
goto free_rec_seq;
}
}
ctx->push_pending_record = tls_sw_push_pending_record;
memcpy(keyval, gcm_128_info->key, TLS_CIPHER_AES_GCM_128_KEY_SIZE);
rc = crypto_aead_setkey(*aead, keyval,
TLS_CIPHER_AES_GCM_128_KEY_SIZE);
if (rc)
goto free_aead;
rc = crypto_aead_setauthsize(*aead, cctx->tag_size);
if (rc)
goto free_aead;
if (sw_ctx_rx) {
(*aead)->reqsize = sizeof(struct decrypt_req_ctx);
/* Set up strparser */
memset(&cb, 0, sizeof(cb));
cb.rcv_msg = tls_queue;
cb.parse_msg = tls_read_size;
strp_init(&sw_ctx_rx->strp, sk, &cb);
write_lock_bh(&sk->sk_callback_lock);
sw_ctx_rx->saved_data_ready = sk->sk_data_ready;
sk->sk_data_ready = tls_data_ready;
write_unlock_bh(&sk->sk_callback_lock);
sw_ctx_rx->sk_poll = sk->sk_socket->ops->poll;
strp_check_rcv(&sw_ctx_rx->strp);
}
goto out;
free_aead:
crypto_free_aead(*aead);
*aead = NULL;
free_rec_seq:
kfree(cctx->rec_seq);
cctx->rec_seq = NULL;
free_iv:
kfree(cctx->iv);
cctx->iv = NULL;
free_priv:
if (tx) {
kfree(ctx->priv_ctx_tx);
ctx->priv_ctx_tx = NULL;
} else {
kfree(ctx->priv_ctx_rx);
ctx->priv_ctx_rx = NULL;
}
out:
return rc;
}