/* Copyright (c) 2018, Mellanox Technologies 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 <crypto/aead.h>
#include <linux/highmem.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <net/dst.h>
#include <net/inet_connection_sock.h>
#include <net/tcp.h>
#include <net/tls.h>
#include <linux/skbuff_ref.h>
#include "tls.h"
#include "trace.h"
/* device_offload_lock is used to synchronize tls_dev_add
* against NETDEV_DOWN notifications.
*/
static DECLARE_RWSEM(device_offload_lock);
static struct workqueue_struct *destruct_wq __read_mostly;
static LIST_HEAD(tls_device_list);
static LIST_HEAD(tls_device_down_list);
static DEFINE_SPINLOCK(tls_device_lock);
static struct page *dummy_page;
static void tls_device_free_ctx(struct tls_context *ctx)
{
if (ctx->tx_conf == TLS_HW)
kfree(tls_offload_ctx_tx(ctx));
if (ctx->rx_conf == TLS_HW)
kfree(tls_offload_ctx_rx(ctx));
tls_ctx_free(NULL, ctx);
}
static void tls_device_tx_del_task(struct work_struct *work)
{
struct tls_offload_context_tx *offload_ctx =
container_of(work, struct tls_offload_context_tx, destruct_work);
struct tls_context *ctx = offload_ctx->ctx;
struct net_device *netdev;
/* Safe, because this is the destroy flow, refcount is 0, so
* tls_device_down can't store this field in parallel.
*/
netdev = rcu_dereference_protected(ctx->netdev,
!refcount_read(&ctx->refcount));
netdev->tlsdev_ops->tls_dev_del(netdev, ctx, TLS_OFFLOAD_CTX_DIR_TX);
dev_put(netdev);
ctx->netdev = NULL;
tls_device_free_ctx(ctx);
}
static void tls_device_queue_ctx_destruction(struct tls_context *ctx)
{
struct net_device *netdev;
unsigned long flags;
bool async_cleanup;
spin_lock_irqsave(&tls_device_lock, flags);
if (unlikely(!refcount_dec_and_test(&ctx->refcount))) {
spin_unlock_irqrestore(&tls_device_lock, flags);
return;
}
list_del(&ctx->list); /* Remove from tls_device_list / tls_device_down_list */
/* Safe, because this is the destroy flow, refcount is 0, so
* tls_device_down can't store this field in parallel.
*/
netdev = rcu_dereference_protected(ctx->netdev,
!refcount_read(&ctx->refcount));
async_cleanup = netdev && ctx->tx_conf == TLS_HW;
if (async_cleanup) {
struct tls_offload_context_tx *offload_ctx = tls_offload_ctx_tx(ctx);
/* queue_work inside the spinlock
* to make sure tls_device_down waits for that work.
*/
queue_work(destruct_wq, &offload_ctx->destruct_work);
}
spin_unlock_irqrestore(&tls_device_lock, flags);
if (!async_cleanup)
tls_device_free_ctx(ctx);
}
/* We assume that the socket is already connected */
static struct net_device *get_netdev_for_sock(struct sock *sk)
{
struct dst_entry *dst = sk_dst_get(sk);
struct net_device *netdev = NULL;
if (likely(dst)) {
netdev = netdev_sk_get_lowest_dev(dst->dev, sk);
dev_hold(netdev);
}
dst_release(dst);
return netdev;
}
static void destroy_record(struct tls_record_info *record)
{
int i;
for (i = 0; i < record->num_frags; i++)
__skb_frag_unref(&record->frags[i], false);
kfree(record);
}
static void delete_all_records(struct tls_offload_context_tx *offload_ctx)
{
struct tls_record_info *info, *temp;
list_for_each_entry_safe(info, temp, &offload_ctx->records_list, list) {
list_del(&info->list);
destroy_record(info);
}
offload_ctx->retransmit_hint = NULL;
}
static void tls_icsk_clean_acked(struct sock *sk, u32 acked_seq)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_record_info *info, *temp;
struct tls_offload_context_tx *ctx;
u64 deleted_records = 0;
unsigned long flags;
if (!tls_ctx)
return;
ctx = tls_offload_ctx_tx(tls_ctx);
spin_lock_irqsave(&ctx->lock, flags);
info = ctx->retransmit_hint;
if (info && !before(acked_seq, info->end_seq))
ctx->retransmit_hint = NULL;
list_for_each_entry_safe(info, temp, &ctx->records_list, list) {
if (before(acked_seq, info->end_seq))
break;
list_del(&info->list);
destroy_record(info);
deleted_records++;
}
ctx->unacked_record_sn += deleted_records;
spin_unlock_irqrestore(&ctx->lock, flags);
}
/* At this point, there should be no references on this
* socket and no in-flight SKBs associated with this
* socket, so it is safe to free all the resources.
*/
void tls_device_sk_destruct(struct sock *sk)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
tls_ctx->sk_destruct(sk);
if (tls_ctx->tx_conf == TLS_HW) {
if (ctx->open_record)
destroy_record(ctx->open_record);
delete_all_records(ctx);
crypto_free_aead(ctx->aead_send);
clean_acked_data_disable(inet_csk(sk));
}
tls_device_queue_ctx_destruction(tls_ctx);
}
EXPORT_SYMBOL_GPL(tls_device_sk_destruct);
void tls_device_free_resources_tx(struct sock *sk)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
tls_free_partial_record(sk, tls_ctx);
}
void tls_offload_tx_resync_request(struct sock *sk, u32 got_seq, u32 exp_seq)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
trace_tls_device_tx_resync_req(sk, got_seq, exp_seq);
WARN_ON(test_and_set_bit(TLS_TX_SYNC_SCHED, &tls_ctx->flags));
}
EXPORT_SYMBOL_GPL(tls_offload_tx_resync_request);
static void tls_device_resync_tx(struct sock *sk, struct tls_context *tls_ctx,
u32 seq)
{
struct net_device *netdev;
int err = 0;
u8 *rcd_sn;
tcp_write_collapse_fence(sk);
rcd_sn = tls_ctx->tx.rec_seq;
trace_tls_device_tx_resync_send(sk, seq, rcd_sn);
down_read(&device_offload_lock);
netdev = rcu_dereference_protected(tls_ctx->netdev,
lockdep_is_held(&device_offload_lock));
if (netdev)
err = netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq,
rcd_sn,
TLS_OFFLOAD_CTX_DIR_TX);
up_read(&device_offload_lock);
if (err)
return;
clear_bit_unlock(TLS_TX_SYNC_SCHED, &tls_ctx->flags);
}
static void tls_append_frag(struct tls_record_info *record,
struct page_frag *pfrag,
int size)
{
skb_frag_t *frag;
frag = &record->frags[record->num_frags - 1];
if (skb_frag_page(frag) == pfrag->page &&
skb_frag_off(frag) + skb_frag_size(frag) == pfrag->offset) {
skb_frag_size_add(frag, size);
} else {
++frag;
skb_frag_fill_page_desc(frag, pfrag->page, pfrag->offset,
size);
++record->num_frags;
get_page(pfrag->page);
}
pfrag->offset += size;
record->len += size;
}
static int tls_push_record(struct sock *sk,
struct tls_context *ctx,
struct tls_offload_context_tx *offload_ctx,
struct tls_record_info *record,
int flags)
{
struct tls_prot_info *prot = &ctx->prot_info;
struct tcp_sock *tp = tcp_sk(sk);
skb_frag_t *frag;
int i;
record->end_seq = tp->write_seq + record->len;
list_add_tail_rcu(&record->list, &offload_ctx->records_list);
offload_ctx->open_record = NULL;
if (test_bit(TLS_TX_SYNC_SCHED, &ctx->flags))
tls_device_resync_tx(sk, ctx, tp->write_seq);
tls_advance_record_sn(sk, prot, &ctx->tx);
for (i = 0; i < record->num_frags; i++) {
frag = &record->frags[i];
sg_unmark_end(&offload_ctx->sg_tx_data[i]);
sg_set_page(&offload_ctx->sg_tx_data[i], skb_frag_page(frag),
skb_frag_size(frag), skb_frag_off(frag));
sk_mem_charge(sk, skb_frag_size(frag));
get_page(skb_frag_page(frag));
}
sg_mark_end(&offload_ctx->sg_tx_data[record->num_frags - 1]);
/* all ready, send */
return tls_push_sg(sk, ctx, offload_ctx->sg_tx_data, 0, flags);
}
static void tls_device_record_close(struct sock *sk,
struct tls_context *ctx,
struct tls_record_info *record,
struct page_frag *pfrag,
unsigned char record_type)
{
struct tls_prot_info *prot = &ctx->prot_info;
struct page_frag dummy_tag_frag;
/* append tag
* device will fill in the tag, we just need to append a placeholder
* use socket memory to improve coalescing (re-using a single buffer
* increases frag count)
* if we can't allocate memory now use the dummy page
*/
if (unlikely(pfrag->size - pfrag->offset < prot->tag_size) &&
!skb_page_frag_refill(prot->tag_size, pfrag, sk->sk_allocation)) {
dummy_tag_frag.page = dummy_page;
dummy_tag_frag.offset = 0;
pfrag = &dummy_tag_frag;
}
tls_append_frag(record, pfrag, prot->tag_size);
/* fill prepend */
tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]),
record->len - prot->overhead_size,
record_type);
}
static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx,
struct page_frag *pfrag,
size_t prepend_size)
{
struct tls_record_info *record;
skb_frag_t *frag;
record = kmalloc(sizeof(*record), GFP_KERNEL);
if (!record)
return -ENOMEM;
frag = &record->frags[0];
skb_frag_fill_page_desc(frag, pfrag->page, pfrag->offset,
prepend_size);
get_page(pfrag->page);
pfrag->offset += prepend_size;
record->num_frags = 1;
record->len = prepend_size;
offload_ctx->open_record = record;
return 0;
}
static int tls_do_allocation(struct sock *sk,
struct tls_offload_context_tx *offload_ctx,
struct page_frag *pfrag,
size_t prepend_size)
{
int ret;
if (!offload_ctx->open_record) {
if (unlikely(!skb_page_frag_refill(prepend_size, pfrag,
sk->sk_allocation))) {
READ_ONCE(sk->sk_prot)->enter_memory_pressure(sk);
sk_stream_moderate_sndbuf(sk);
return -ENOMEM;
}
ret = tls_create_new_record(offload_ctx, pfrag, prepend_size);
if (ret)
return ret;
if (pfrag->size > pfrag->offset)
return 0;
}
if (!sk_page_frag_refill(sk, pfrag))
return -ENOMEM;
return 0;
}
static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i)
{
size_t pre_copy, nocache;
pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1);
if (pre_copy) {
pre_copy = min(pre_copy, bytes);
if (copy_from_iter(addr, pre_copy, i) != pre_copy)
return -EFAULT;
bytes -= pre_copy;
addr += pre_copy;
}
nocache = round_down(bytes, SMP_CACHE_BYTES);
if (copy_from_iter_nocache(addr, nocache, i) != nocache)
return -EFAULT;
bytes -= nocache;
addr += nocache;
if (bytes && copy_from_iter(addr, bytes, i) != bytes)
return -EFAULT;
return 0;
}
static int tls_push_data(struct sock *sk,
struct iov_iter *iter,
size_t size, int flags,
unsigned char record_type)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_prot_info *prot = &tls_ctx->prot_info;
struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
struct tls_record_info *record;
int tls_push_record_flags;
struct page_frag *pfrag;
size_t orig_size = size;
u32 max_open_record_len;
bool more = false;
bool done = false;
int copy, rc = 0;
long timeo;
if (flags &
~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
MSG_SPLICE_PAGES | MSG_EOR))
return -EOPNOTSUPP;
if ((flags & (MSG_MORE | MSG_EOR)) == (MSG_MORE | MSG_EOR))
return -EINVAL;
if (unlikely(sk->sk_err))
return -sk->sk_err;
flags |= MSG_SENDPAGE_DECRYPTED;
tls_push_record_flags = flags | MSG_MORE;
timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
if (tls_is_partially_sent_record(tls_ctx)) {
rc = tls_push_partial_record(sk, tls_ctx, flags);
if (rc < 0)
return rc;
}
pfrag = sk_page_frag(sk);
/* TLS_HEADER_SIZE is not counted as part of the TLS record, and
* we need to leave room for an authentication tag.
*/
max_open_record_len = TLS_MAX_PAYLOAD_SIZE +
prot->prepend_size;
do {
rc = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size);
if (unlikely(rc)) {
rc = sk_stream_wait_memory(sk, &timeo);
if (!rc)
continue;
record = ctx->open_record;
if (!record)
break;
handle_error:
if (record_type != TLS_RECORD_TYPE_DATA) {
/* avoid sending partial
* record with type !=
* application_data
*/
size = orig_size;
destroy_record(record);
ctx->open_record = NULL;
} else if (record->len > prot->prepend_size) {
goto last_record;
}
break;
}
record = ctx->open_record;
copy = min_t(size_t, size, max_open_record_len - record->len);
if (copy && (flags & MSG_SPLICE_PAGES)) {
struct page_frag zc_pfrag;
struct page **pages = &zc_pfrag.page;
size_t off;
rc = iov_iter_extract_pages(iter, &pages,
copy, 1, 0, &off);
if (rc <= 0) {
if (rc == 0)
rc = -EIO;
goto handle_error;
}
copy = rc;
if (WARN_ON_ONCE(!sendpage_ok(zc_pfrag.page))) {
iov_iter_revert(iter, copy);
rc = -EIO;
goto handle_error;
}
zc_pfrag.offset = off;
zc_pfrag.size = copy;
tls_append_frag(record, &zc_pfrag, copy);
} else if (copy) {
copy = min_t(size_t, copy, pfrag->size - pfrag->offset);
rc = tls_device_copy_data(page_address(pfrag->page) +
pfrag->offset, copy,
iter);
if (rc)
goto handle_error;
tls_append_frag(record, pfrag, copy);
}
size -= copy;
if (!size) {
last_record:
tls_push_record_flags = flags;
if (flags & MSG_MORE) {
more = true;
break;
}
done = true;
}
if (done || record->len >= max_open_record_len ||
(record->num_frags >= MAX_SKB_FRAGS - 1)) {
tls_device_record_close(sk, tls_ctx, record,
pfrag, record_type);
rc = tls_push_record(sk,
tls_ctx,
ctx,
record,
tls_push_record_flags);
if (rc < 0)
break;
}
} while (!done);
tls_ctx->pending_open_record_frags = more;
if (orig_size - size > 0)
rc = orig_size - size;
return rc;
}
int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
{
unsigned char record_type = TLS_RECORD_TYPE_DATA;
struct tls_context *tls_ctx = tls_get_ctx(sk);
int rc;
if (!tls_ctx->zerocopy_sendfile)
msg->msg_flags &= ~MSG_SPLICE_PAGES;
mutex_lock(&tls_ctx->tx_lock);
lock_sock(sk);
if (unlikely(msg->msg_controllen)) {
rc = tls_process_cmsg(sk, msg, &record_type);
if (rc)
goto out;
}
rc = tls_push_data(sk, &msg->msg_iter, size, msg->msg_flags,
record_type);
out:
release_sock(sk);
mutex_unlock(&tls_ctx->tx_lock);
return rc;
}
void tls_device_splice_eof(struct socket *sock)
{
struct sock *sk = sock->sk;
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct iov_iter iter = {};
if (!tls_is_partially_sent_record(tls_ctx))
return;
mutex_lock(&tls_ctx->tx_lock);
lock_sock(sk);
if (tls_is_partially_sent_record(tls_ctx)) {
iov_iter_bvec(&iter, ITER_SOURCE, NULL, 0, 0);
tls_push_data(sk, &iter, 0, 0, TLS_RECORD_TYPE_DATA);
}
release_sock(sk);
mutex_unlock(&tls_ctx->tx_lock);
}
struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
u32 seq, u64 *p_record_sn)
{
u64 record_sn = context->hint_record_sn;
struct tls_record_info *info, *last;
info = context->retransmit_hint;
if (!info ||
before(seq, info->end_seq - info->len)) {
/* if retransmit_hint is irrelevant start
* from the beginning of the list
*/
info = list_first_entry_or_null(&context->records_list,
struct tls_record_info, list);
if (!info)
return NULL;
/* send the start_marker record if seq number is before the
* tls offload start marker sequence number. This record is
* required to handle TCP packets which are before TLS offload
* started.
* And if it's not start marker, look if this seq number
* belongs to the list.
*/
if (likely(!tls_record_is_start_marker(info))) {
/* we have the first record, get the last record to see
* if this seq number belongs to the list.
*/
last = list_last_entry(&context->records_list,
struct tls_record_info, list);
if (!between(seq, tls_record_start_seq(info),
last->end_seq))
return NULL;
}
record_sn = context->unacked_record_sn;
}
/* We just need the _rcu for the READ_ONCE() */
rcu_read_lock();
list_for_each_entry_from_rcu(info, &context->records_list, list) {
if (before(seq, info->end_seq)) {
if (!context->retransmit_hint ||
after(info->end_seq,
context->retransmit_hint->end_seq)) {
context->hint_record_sn = record_sn;
context->retransmit_hint = info;
}
*p_record_sn = record_sn;
goto exit_rcu_unlock;
}
record_sn++;
}
info = NULL;
exit_rcu_unlock:
rcu_read_unlock();
return info;
}
EXPORT_SYMBOL(tls_get_record);
static int tls_device_push_pending_record(struct sock *sk, int flags)
{
struct iov_iter iter;
iov_iter_kvec(&iter, ITER_SOURCE, NULL, 0, 0);
return tls_push_data(sk, &iter, 0, flags, TLS_RECORD_TYPE_DATA);
}
void tls_device_write_space(struct sock *sk, struct tls_context *ctx)
{
if (tls_is_partially_sent_record(ctx)) {
gfp_t sk_allocation = sk->sk_allocation;
WARN_ON_ONCE(sk->sk_write_pending);
sk->sk_allocation = GFP_ATOMIC;
tls_push_partial_record(sk, ctx,
MSG_DONTWAIT | MSG_NOSIGNAL |
MSG_SENDPAGE_DECRYPTED);
sk->sk_allocation = sk_allocation;
}
}
static void tls_device_resync_rx(struct tls_context *tls_ctx,
struct sock *sk, u32 seq, u8 *rcd_sn)
{
struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);
struct net_device *netdev;
trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type);
rcu_read_lock();
netdev = rcu_dereference(tls_ctx->netdev);
if (netdev)
netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn,
TLS_OFFLOAD_CTX_DIR_RX);
rcu_read_unlock();
TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC);
}
static bool
tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async,
s64 resync_req, u32 *seq, u16 *rcd_delta)
{
u32 is_async = resync_req & RESYNC_REQ_ASYNC;
u32 req_seq = resync_req >> 32;
u32 req_end = req_seq + ((resync_req >> 16) & 0xffff);
u16 i;
*rcd_delta = 0;
if (is_async) {
/* shouldn't get to wraparound:
* too long in async stage, something bad happened
*/
if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX))
return false;
/* asynchronous stage: log all headers seq such that
* req_seq <= seq <= end_seq, and wait for real resync request
*/
if (before(*seq, req_seq))
return false;
if (!after(*seq, req_end) &&
resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX)
resync_async->log[resync_async->loglen++] = *seq;
resync_async->rcd_delta++;
return false;
}
/* synchronous stage: check against the logged entries and
* proceed to check the next entries if no match was found
*/
for (i = 0; i < resync_async->loglen; i++)
if (req_seq == resync_async->log[i] &&
atomic64_try_cmpxchg(&resync_async->req, &resync_req, 0)) {
*rcd_delta = resync_async->rcd_delta - i;
*seq = req_seq;
resync_async->loglen = 0;
resync_async->rcd_delta = 0;
return true;
}
resync_async->loglen = 0;
resync_async->rcd_delta = 0;
if (req_seq == *seq &&
atomic64_try_cmpxchg(&resync_async->req,
&resync_req, 0))
return true;
return false;
}
void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct tls_offload_context_rx *rx_ctx;
u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
u32 sock_data, is_req_pending;
struct tls_prot_info *prot;
s64 resync_req;
u16 rcd_delta;
u32 req_seq;
if (tls_ctx->rx_conf != TLS_HW)
return;
if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags)))
return;
prot = &tls_ctx->prot_info;
rx_ctx = tls_offload_ctx_rx(tls_ctx);
memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
switch (rx_ctx->resync_type) {
case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ:
resync_req = atomic64_read(&rx_ctx->resync_req);
req_seq = resync_req >> 32;
seq += TLS_HEADER_SIZE - 1;
is_req_pending = resync_req;
if (likely(!is_req_pending) || req_seq != seq ||
!atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0))
return;
break;
case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT:
if (likely(!rx_ctx->resync_nh_do_now))
return;
/* head of next rec is already in, note that the sock_inq will
* include the currently parsed message when called from parser
*/
sock_data = tcp_inq(sk);
if (sock_data > rcd_len) {
trace_tls_device_rx_resync_nh_delay(sk, sock_data,
rcd_len);
return;
}
rx_ctx->resync_nh_do_now = 0;
seq += rcd_len;
tls_bigint_increment(rcd_sn, prot->rec_seq_size);
break;
case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC:
resync_req = atomic64_read(&rx_ctx->resync_async->req);
is_req_pending = resync_req;
if (likely(!is_req_pending))
return;
if (!tls_device_rx_resync_async(rx_ctx->resync_async,
resync_req, &seq, &rcd_delta))
return;
tls_bigint_subtract(rcd_sn, rcd_delta);
break;
}
tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn);
}
static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx,
struct tls_offload_context_rx *ctx,
struct sock *sk, struct sk_buff *skb)
{
struct strp_msg *rxm;
/* device will request resyncs by itself based on stream scan */
if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT)
return;
/* already scheduled */
if (ctx->resync_nh_do_now)
return;
/* seen decrypted fragments since last fully-failed record */
if (ctx->resync_nh_reset) {
ctx->resync_nh_reset = 0;
ctx->resync_nh.decrypted_failed = 1;
ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL;
return;
}
if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt)
return;
/* doing resync, bump the next target in case it fails */
if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL)
ctx->resync_nh.decrypted_tgt *= 2;
else
ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL;
rxm = strp_msg(skb);
/* head of next rec is already in, parser will sync for us */
if (tcp_inq(sk) > rxm->full_len) {
trace_tls_device_rx_resync_nh_schedule(sk);
ctx->resync_nh_do_now = 1;
} else {
struct tls_prot_info *prot = &tls_ctx->prot_info;
u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
tls_bigint_increment(rcd_sn, prot->rec_seq_size);
tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq,
rcd_sn);
}
}
static int
tls_device_reencrypt(struct sock *sk, struct tls_context *tls_ctx)
{
struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx);
const struct tls_cipher_desc *cipher_desc;
int err, offset, copy, data_len, pos;
struct sk_buff *skb, *skb_iter;
struct scatterlist sg[1];
struct strp_msg *rxm;
char *orig_buf, *buf;
cipher_desc = get_cipher_desc(tls_ctx->crypto_recv.info.cipher_type);
DEBUG_NET_WARN_ON_ONCE(!cipher_desc || !cipher_desc->offloadable);
rxm = strp_msg(tls_strp_msg(sw_ctx));
orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE + cipher_desc->iv,
sk->sk_allocation);
if (!orig_buf)
return -ENOMEM;
buf = orig_buf;
err = tls_strp_msg_cow(sw_ctx);
if (unlikely(err))
goto free_buf;
skb = tls_strp_msg(sw_ctx);
rxm = strp_msg(skb);
offset = rxm->offset;
sg_init_table(sg, 1);
sg_set_buf(&sg[0], buf,
rxm->full_len + TLS_HEADER_SIZE + cipher_desc->iv);
err = skb_copy_bits(skb, offset, buf, TLS_HEADER_SIZE + cipher_desc->iv);
if (err)
goto free_buf;
/* We are interested only in the decrypted data not the auth */
err = decrypt_skb(sk, sg);
if (err != -EBADMSG)
goto free_buf;
else
err = 0;
data_len = rxm->full_len - cipher_desc->tag;
if (skb_pagelen(skb) > offset) {
copy = min_t(int, skb_pagelen(skb) - offset, data_len);
if (skb->decrypted) {
err = skb_store_bits(skb, offset, buf, copy);
if (err)
goto free_buf;
}
offset += copy;
buf += copy;
}
pos = skb_pagelen(skb);
skb_walk_frags(skb, skb_iter) {
int frag_pos;
/* Practically all frags must belong to msg if reencrypt
* is needed with current strparser and coalescing logic,
* but strparser may "get optimized", so let's be safe.
*/
if (pos + skb_iter->len <= offset)
goto done_with_frag;
if (pos >= data_len + rxm->offset)
break;
frag_pos = offset - pos;
copy = min_t(int, skb_iter->len - frag_pos,
data_len + rxm->offset - offset);
if (skb_iter->decrypted) {
err = skb_store_bits(skb_iter, frag_pos, buf, copy);
if (err)
goto free_buf;
}
offset += copy;
buf += copy;
done_with_frag:
pos += skb_iter->len;
}
free_buf:
kfree(orig_buf);
return err;
}
int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx)
{
struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx);
struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx);
struct sk_buff *skb = tls_strp_msg(sw_ctx);
struct strp_msg *rxm = strp_msg(skb);
int is_decrypted, is_encrypted;
if (!tls_strp_msg_mixed_decrypted(sw_ctx)) {
is_decrypted = skb->decrypted;
is_encrypted = !is_decrypted;
} else {
is_decrypted = 0;
is_encrypted = 0;
}
trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len,
tls_ctx->rx.rec_seq, rxm->full_len,
is_encrypted, is_decrypted);
if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) {
if (likely(is_encrypted || is_decrypted))
return is_decrypted;
/* After tls_device_down disables the offload, the next SKB will
* likely have initial fragments decrypted, and final ones not
* decrypted. We need to reencrypt that single SKB.
*/
return tls_device_reencrypt(sk, tls_ctx);
}
/* Return immediately if the record is either entirely plaintext or
* entirely ciphertext. Otherwise handle reencrypt partially decrypted
* record.
*/
if (is_decrypted) {
ctx->resync_nh_reset = 1;
return is_decrypted;
}
if (is_encrypted) {
tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb);
return 0;
}
ctx->resync_nh_reset = 1;
return tls_device_reencrypt(sk, tls_ctx);
}
static void tls_device_attach(struct tls_context *ctx, struct sock *sk,
struct net_device *netdev)
{
if (sk->sk_destruct != tls_device_sk_destruct) {
refcount_set(&ctx->refcount, 1);
dev_hold(netdev);
RCU_INIT_POINTER(ctx->netdev, netdev);
spin_lock_irq(&tls_device_lock);
list_add_tail(&ctx->list, &tls_device_list);
spin_unlock_irq(&tls_device_lock);
ctx->sk_destruct = sk->sk_destruct;
smp_store_release(&sk->sk_destruct, tls_device_sk_destruct);
}
}
static struct tls_offload_context_tx *alloc_offload_ctx_tx(struct tls_context *ctx)
{
struct tls_offload_context_tx *offload_ctx;
__be64 rcd_sn;
offload_ctx = kzalloc(sizeof(*offload_ctx), GFP_KERNEL);
if (!offload_ctx)
return NULL;
INIT_WORK(&offload_ctx->destruct_work, tls_device_tx_del_task);
INIT_LIST_HEAD(&offload_ctx->records_list);
spin_lock_init(&offload_ctx->lock);
sg_init_table(offload_ctx->sg_tx_data,
ARRAY_SIZE(offload_ctx->sg_tx_data));
/* start at rec_seq - 1 to account for the start marker record */
memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn));
offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1;
offload_ctx->ctx = ctx;
return offload_ctx;
}
int tls_set_device_offload(struct sock *sk)
{
struct tls_record_info *start_marker_record;
struct tls_offload_context_tx *offload_ctx;
const struct tls_cipher_desc *cipher_desc;
struct tls_crypto_info *crypto_info;
struct tls_prot_info *prot;
struct net_device *netdev;
struct tls_context *ctx;
char *iv, *rec_seq;
int rc;
ctx = tls_get_ctx(sk);
prot = &ctx->prot_info;
if (ctx->priv_ctx_tx)
return -EEXIST;
netdev = get_netdev_for_sock(sk);
if (!netdev) {
pr_err_ratelimited("%s: netdev not found\n", __func__);
return -EINVAL;
}
if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
rc = -EOPNOTSUPP;
goto release_netdev;
}
crypto_info = &ctx->crypto_send.info;
if (crypto_info->version != TLS_1_2_VERSION) {
rc = -EOPNOTSUPP;
goto release_netdev;
}
cipher_desc = get_cipher_desc(crypto_info->cipher_type);
if (!cipher_desc || !cipher_desc->offloadable) {
rc = -EINVAL;
goto release_netdev;
}
rc = init_prot_info(prot, crypto_info, cipher_desc);
if (rc)
goto release_netdev;
iv = crypto_info_iv(crypto_info, cipher_desc);
rec_seq = crypto_info_rec_seq(crypto_info, cipher_desc);
memcpy(ctx->tx.iv + cipher_desc->salt, iv, cipher_desc->iv);
memcpy(ctx->tx.rec_seq, rec_seq, cipher_desc->rec_seq);
start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
if (!start_marker_record) {
rc = -ENOMEM;
goto release_netdev;
}
offload_ctx = alloc_offload_ctx_tx(ctx);
if (!offload_ctx) {
rc = -ENOMEM;
goto free_marker_record;
}
rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info);
if (rc)
goto free_offload_ctx;
start_marker_record->end_seq = tcp_sk(sk)->write_seq;
start_marker_record->len = 0;
start_marker_record->num_frags = 0;
list_add_tail(&start_marker_record->list, &offload_ctx->records_list);
clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked);
ctx->push_pending_record = tls_device_push_pending_record;
/* TLS offload is greatly simplified if we don't send
* SKBs where only part of the payload needs to be encrypted.
* So mark the last skb in the write queue as end of record.
*/
tcp_write_collapse_fence(sk);
/* Avoid offloading if the device is down
* We don't want to offload new flows after
* the NETDEV_DOWN event
*
* device_offload_lock is taken in tls_devices's NETDEV_DOWN
* handler thus protecting from the device going down before
* ctx was added to tls_device_list.
*/
down_read(&device_offload_lock);
if (!(netdev->flags & IFF_UP)) {
rc = -EINVAL;
goto release_lock;
}
ctx->priv_ctx_tx = offload_ctx;
rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX,
&ctx->crypto_send.info,
tcp_sk(sk)->write_seq);
trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX,
tcp_sk(sk)->write_seq, rec_seq, rc);
if (rc)
goto release_lock;
tls_device_attach(ctx, sk, netdev);
up_read(&device_offload_lock);
/* following this assignment tls_is_skb_tx_device_offloaded
* will return true and the context might be accessed
* by the netdev's xmit function.
*/
smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb);
dev_put(netdev);
return 0;
release_lock:
up_read(&device_offload_lock);
clean_acked_data_disable(inet_csk(sk));
crypto_free_aead(offload_ctx->aead_send);
free_offload_ctx:
kfree(offload_ctx);
ctx->priv_ctx_tx = NULL;
free_marker_record:
kfree(start_marker_record);
release_netdev:
dev_put(netdev);
return rc;
}
int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
{
struct tls12_crypto_info_aes_gcm_128 *info;
struct tls_offload_context_rx *context;
struct net_device *netdev;
int rc = 0;
if (ctx->crypto_recv.info.version != TLS_1_2_VERSION)
return -EOPNOTSUPP;
netdev = get_netdev_for_sock(sk);
if (!netdev) {
pr_err_ratelimited("%s: netdev not found\n", __func__);
return -EINVAL;
}
if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
rc = -EOPNOTSUPP;
goto release_netdev;
}
/* Avoid offloading if the device is down
* We don't want to offload new flows after
* the NETDEV_DOWN event
*
* device_offload_lock is taken in tls_devices's NETDEV_DOWN
* handler thus protecting from the device going down before
* ctx was added to tls_device_list.
*/
down_read(&device_offload_lock);
if (!(netdev->flags & IFF_UP)) {
rc = -EINVAL;
goto release_lock;
}
context = kzalloc(sizeof(*context), GFP_KERNEL);
if (!context) {
rc = -ENOMEM;
goto release_lock;
}
context->resync_nh_reset = 1;
ctx->priv_ctx_rx = context;
rc = tls_set_sw_offload(sk, 0);
if (rc)
goto release_ctx;
rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX,
&ctx->crypto_recv.info,
tcp_sk(sk)->copied_seq);
info = (void *)&ctx->crypto_recv.info;
trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX,
tcp_sk(sk)->copied_seq, info->rec_seq, rc);
if (rc)
goto free_sw_resources;
tls_device_attach(ctx, sk, netdev);
up_read(&device_offload_lock);
dev_put(netdev);
return 0;
free_sw_resources:
up_read(&device_offload_lock);
tls_sw_free_resources_rx(sk);
down_read(&device_offload_lock);
release_ctx:
ctx->priv_ctx_rx = NULL;
release_lock:
up_read(&device_offload_lock);
release_netdev:
dev_put(netdev);
return rc;
}
void tls_device_offload_cleanup_rx(struct sock *sk)
{
struct tls_context *tls_ctx = tls_get_ctx(sk);
struct net_device *netdev;
down_read(&device_offload_lock);
netdev = rcu_dereference_protected(tls_ctx->netdev,
lockdep_is_held(&device_offload_lock));
if (!netdev)
goto out;
netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx,
TLS_OFFLOAD_CTX_DIR_RX);
if (tls_ctx->tx_conf != TLS_HW) {
dev_put(netdev);
rcu_assign_pointer(tls_ctx->netdev, NULL);
} else {
set_bit(TLS_RX_DEV_CLOSED, &tls_ctx->flags);
}
out:
up_read(&device_offload_lock);
tls_sw_release_resources_rx(sk);
}
static int tls_device_down(struct net_device *netdev)
{
struct tls_context *ctx, *tmp;
unsigned long flags;
LIST_HEAD(list);
/* Request a write lock to block new offload attempts */
down_write(&device_offload_lock);
spin_lock_irqsave(&tls_device_lock, flags);
list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) {
struct net_device *ctx_netdev =
rcu_dereference_protected(ctx->netdev,
lockdep_is_held(&device_offload_lock));
if (ctx_netdev != netdev ||
!refcount_inc_not_zero(&ctx->refcount))
continue;
list_move(&ctx->list, &list);
}
spin_unlock_irqrestore(&tls_device_lock, flags);
list_for_each_entry_safe(ctx, tmp, &list, list) {
/* Stop offloaded TX and switch to the fallback.
* tls_is_skb_tx_device_offloaded will return false.
*/
WRITE_ONCE(ctx->sk->sk_validate_xmit_skb, tls_validate_xmit_skb_sw);
/* Stop the RX and TX resync.
* tls_dev_resync must not be called after tls_dev_del.
*/
rcu_assign_pointer(ctx->netdev, NULL);
/* Start skipping the RX resync logic completely. */
set_bit(TLS_RX_DEV_DEGRADED, &ctx->flags);
/* Sync with inflight packets. After this point:
* TX: no non-encrypted packets will be passed to the driver.
* RX: resync requests from the driver will be ignored.
*/
synchronize_net();
/* Release the offload context on the driver side. */
if (ctx->tx_conf == TLS_HW)
netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
TLS_OFFLOAD_CTX_DIR_TX);
if (ctx->rx_conf == TLS_HW &&
!test_bit(TLS_RX_DEV_CLOSED, &ctx->flags))
netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
TLS_OFFLOAD_CTX_DIR_RX);
dev_put(netdev);
/* Move the context to a separate list for two reasons:
* 1. When the context is deallocated, list_del is called.
* 2. It's no longer an offloaded context, so we don't want to
* run offload-specific code on this context.
*/
spin_lock_irqsave(&tls_device_lock, flags);
list_move_tail(&ctx->list, &tls_device_down_list);
spin_unlock_irqrestore(&tls_device_lock, flags);
/* Device contexts for RX and TX will be freed in on sk_destruct
* by tls_device_free_ctx. rx_conf and tx_conf stay in TLS_HW.
* Now release the ref taken above.
*/
if (refcount_dec_and_test(&ctx->refcount)) {
/* sk_destruct ran after tls_device_down took a ref, and
* it returned early. Complete the destruction here.
*/
list_del(&ctx->list);
tls_device_free_ctx(ctx);
}
}
up_write(&device_offload_lock);
flush_workqueue(destruct_wq);
return NOTIFY_DONE;
}
static int tls_dev_event(struct notifier_block *this, unsigned long event,
void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
if (!dev->tlsdev_ops &&
!(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX)))
return NOTIFY_DONE;
switch (event) {
case NETDEV_REGISTER:
case NETDEV_FEAT_CHANGE:
if (netif_is_bond_master(dev))
return NOTIFY_DONE;
if ((dev->features & NETIF_F_HW_TLS_RX) &&
!dev->tlsdev_ops->tls_dev_resync)
return NOTIFY_BAD;
if (dev->tlsdev_ops &&
dev->tlsdev_ops->tls_dev_add &&
dev->tlsdev_ops->tls_dev_del)
return NOTIFY_DONE;
else
return NOTIFY_BAD;
case NETDEV_DOWN:
return tls_device_down(dev);
}
return NOTIFY_DONE;
}
static struct notifier_block tls_dev_notifier = {
.notifier_call = tls_dev_event,
};
int __init tls_device_init(void)
{
int err;
dummy_page = alloc_page(GFP_KERNEL);
if (!dummy_page)
return -ENOMEM;
destruct_wq = alloc_workqueue("ktls_device_destruct", 0, 0);
if (!destruct_wq) {
err = -ENOMEM;
goto err_free_dummy;
}
err = register_netdevice_notifier(&tls_dev_notifier);
if (err)
goto err_destroy_wq;
return 0;
err_destroy_wq:
destroy_workqueue(destruct_wq);
err_free_dummy:
put_page(dummy_page);
return err;
}
void __exit tls_device_cleanup(void)
{
unregister_netdevice_notifier(&tls_dev_notifier);
destroy_workqueue(destruct_wq);
clean_acked_data_flush();
put_page(dummy_page);
}
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