linux-stable/net/tls/tls_main.c
John Fastabend 28cb6f1eaf bpf: tls_sw, init TLS ULP removes BPF proto hooks
The existing code did not expect users would initialize the TLS ULP
without subsequently calling the TLS TX enabling socket option.
If the application tries to send data after the TLS ULP enable op
but before the TLS TX enable op the BPF sk_msg verdict program is
skipped. This patch resolves this by converting the ipv4 sock ops
to be calculated at init time the same way ipv6 ops are done. This
pulls in any changes to the sock ops structure that have been made
after the socket was created including the changes from adding the
socket to a sock{map|hash}.

This was discovered by running OpenSSL master branch which calls
the TLS ULP setsockopt early in TLS handshake but only enables
the TLS TX path once the handshake has completed. As a result the
datapath missed the initial handshake messages.

Fixes: 02c558b2d5 ("bpf: sockmap, support for msg_peek in sk_msg with redirect ingress")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-12-20 23:47:09 +01:00

756 lines
17 KiB
C

/*
* Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved.
* Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. 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/module.h>
#include <net/tcp.h>
#include <net/inet_common.h>
#include <linux/highmem.h>
#include <linux/netdevice.h>
#include <linux/sched/signal.h>
#include <linux/inetdevice.h>
#include <net/tls.h>
MODULE_AUTHOR("Mellanox Technologies");
MODULE_DESCRIPTION("Transport Layer Security Support");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_ALIAS_TCP_ULP("tls");
enum {
TLSV4,
TLSV6,
TLS_NUM_PROTS,
};
static struct proto *saved_tcpv6_prot;
static DEFINE_MUTEX(tcpv6_prot_mutex);
static struct proto *saved_tcpv4_prot;
static DEFINE_MUTEX(tcpv4_prot_mutex);
static LIST_HEAD(device_list);
static DEFINE_MUTEX(device_mutex);
static struct proto tls_prots[TLS_NUM_PROTS][TLS_NUM_CONFIG][TLS_NUM_CONFIG];
static struct proto_ops tls_sw_proto_ops;
static void update_sk_prot(struct sock *sk, struct tls_context *ctx)
{
int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
sk->sk_prot = &tls_prots[ip_ver][ctx->tx_conf][ctx->rx_conf];
}
int wait_on_pending_writer(struct sock *sk, long *timeo)
{
int rc = 0;
DEFINE_WAIT_FUNC(wait, woken_wake_function);
add_wait_queue(sk_sleep(sk), &wait);
while (1) {
if (!*timeo) {
rc = -EAGAIN;
break;
}
if (signal_pending(current)) {
rc = sock_intr_errno(*timeo);
break;
}
if (sk_wait_event(sk, timeo, !sk->sk_write_pending, &wait))
break;
}
remove_wait_queue(sk_sleep(sk), &wait);
return rc;
}
int tls_push_sg(struct sock *sk,
struct tls_context *ctx,
struct scatterlist *sg,
u16 first_offset,
int flags)
{
int sendpage_flags = flags | MSG_SENDPAGE_NOTLAST;
int ret = 0;
struct page *p;
size_t size;
int offset = first_offset;
size = sg->length - offset;
offset += sg->offset;
ctx->in_tcp_sendpages = true;
while (1) {
if (sg_is_last(sg))
sendpage_flags = flags;
/* is sending application-limited? */
tcp_rate_check_app_limited(sk);
p = sg_page(sg);
retry:
ret = do_tcp_sendpages(sk, p, offset, size, sendpage_flags);
if (ret != size) {
if (ret > 0) {
offset += ret;
size -= ret;
goto retry;
}
offset -= sg->offset;
ctx->partially_sent_offset = offset;
ctx->partially_sent_record = (void *)sg;
ctx->in_tcp_sendpages = false;
return ret;
}
put_page(p);
sk_mem_uncharge(sk, sg->length);
sg = sg_next(sg);
if (!sg)
break;
offset = sg->offset;
size = sg->length;
}
ctx->in_tcp_sendpages = false;
ctx->sk_write_space(sk);
return 0;
}
static int tls_handle_open_record(struct sock *sk, int flags)
{
struct tls_context *ctx = tls_get_ctx(sk);
if (tls_is_pending_open_record(ctx))
return ctx->push_pending_record(sk, flags);
return 0;
}
int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
unsigned char *record_type)
{
struct cmsghdr *cmsg;
int rc = -EINVAL;
for_each_cmsghdr(cmsg, msg) {
if (!CMSG_OK(msg, cmsg))
return -EINVAL;
if (cmsg->cmsg_level != SOL_TLS)
continue;
switch (cmsg->cmsg_type) {
case TLS_SET_RECORD_TYPE:
if (cmsg->cmsg_len < CMSG_LEN(sizeof(*record_type)))
return -EINVAL;
if (msg->msg_flags & MSG_MORE)
return -EINVAL;
rc = tls_handle_open_record(sk, msg->msg_flags);
if (rc)
return rc;
*record_type = *(unsigned char *)CMSG_DATA(cmsg);
rc = 0;
break;
default:
return -EINVAL;
}
}
return rc;
}
int tls_push_partial_record(struct sock *sk, struct tls_context *ctx,
int flags)
{
struct scatterlist *sg;
u16 offset;
sg = ctx->partially_sent_record;
offset = ctx->partially_sent_offset;
ctx->partially_sent_record = NULL;
return tls_push_sg(sk, ctx, sg, offset, flags);
}
int tls_push_pending_closed_record(struct sock *sk,
struct tls_context *tls_ctx,
int flags, long *timeo)
{
struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
if (tls_is_partially_sent_record(tls_ctx) ||
!list_empty(&ctx->tx_list))
return tls_tx_records(sk, flags);
else
return tls_ctx->push_pending_record(sk, flags);
}
static void tls_write_space(struct sock *sk)
{
struct tls_context *ctx = tls_get_ctx(sk);
struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx);
/* If in_tcp_sendpages call lower protocol write space handler
* to ensure we wake up any waiting operations there. For example
* if do_tcp_sendpages where to call sk_wait_event.
*/
if (ctx->in_tcp_sendpages) {
ctx->sk_write_space(sk);
return;
}
/* Schedule the transmission if tx list is ready */
if (is_tx_ready(tx_ctx) && !sk->sk_write_pending) {
/* Schedule the transmission */
if (!test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))
schedule_delayed_work(&tx_ctx->tx_work.work, 0);
}
ctx->sk_write_space(sk);
}
static void tls_ctx_free(struct tls_context *ctx)
{
if (!ctx)
return;
memzero_explicit(&ctx->crypto_send, sizeof(ctx->crypto_send));
memzero_explicit(&ctx->crypto_recv, sizeof(ctx->crypto_recv));
kfree(ctx);
}
static void tls_sk_proto_close(struct sock *sk, long timeout)
{
struct tls_context *ctx = tls_get_ctx(sk);
long timeo = sock_sndtimeo(sk, 0);
void (*sk_proto_close)(struct sock *sk, long timeout);
bool free_ctx = false;
lock_sock(sk);
sk_proto_close = ctx->sk_proto_close;
if ((ctx->tx_conf == TLS_HW_RECORD && ctx->rx_conf == TLS_HW_RECORD) ||
(ctx->tx_conf == TLS_BASE && ctx->rx_conf == TLS_BASE)) {
free_ctx = true;
goto skip_tx_cleanup;
}
if (!tls_complete_pending_work(sk, ctx, 0, &timeo))
tls_handle_open_record(sk, 0);
/* We need these for tls_sw_fallback handling of other packets */
if (ctx->tx_conf == TLS_SW) {
kfree(ctx->tx.rec_seq);
kfree(ctx->tx.iv);
tls_sw_free_resources_tx(sk);
}
if (ctx->rx_conf == TLS_SW) {
kfree(ctx->rx.rec_seq);
kfree(ctx->rx.iv);
tls_sw_free_resources_rx(sk);
}
#ifdef CONFIG_TLS_DEVICE
if (ctx->rx_conf == TLS_HW)
tls_device_offload_cleanup_rx(sk);
if (ctx->tx_conf != TLS_HW && ctx->rx_conf != TLS_HW) {
#else
{
#endif
tls_ctx_free(ctx);
ctx = NULL;
}
skip_tx_cleanup:
release_sock(sk);
sk_proto_close(sk, timeout);
/* free ctx for TLS_HW_RECORD, used by tcp_set_state
* for sk->sk_prot->unhash [tls_hw_unhash]
*/
if (free_ctx)
tls_ctx_free(ctx);
}
static int do_tls_getsockopt_tx(struct sock *sk, char __user *optval,
int __user *optlen)
{
int rc = 0;
struct tls_context *ctx = tls_get_ctx(sk);
struct tls_crypto_info *crypto_info;
int len;
if (get_user(len, optlen))
return -EFAULT;
if (!optval || (len < sizeof(*crypto_info))) {
rc = -EINVAL;
goto out;
}
if (!ctx) {
rc = -EBUSY;
goto out;
}
/* get user crypto info */
crypto_info = &ctx->crypto_send.info;
if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
rc = -EBUSY;
goto out;
}
if (len == sizeof(*crypto_info)) {
if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
rc = -EFAULT;
goto out;
}
switch (crypto_info->cipher_type) {
case TLS_CIPHER_AES_GCM_128: {
struct tls12_crypto_info_aes_gcm_128 *
crypto_info_aes_gcm_128 =
container_of(crypto_info,
struct tls12_crypto_info_aes_gcm_128,
info);
if (len != sizeof(*crypto_info_aes_gcm_128)) {
rc = -EINVAL;
goto out;
}
lock_sock(sk);
memcpy(crypto_info_aes_gcm_128->iv,
ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
TLS_CIPHER_AES_GCM_128_IV_SIZE);
memcpy(crypto_info_aes_gcm_128->rec_seq, ctx->tx.rec_seq,
TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
release_sock(sk);
if (copy_to_user(optval,
crypto_info_aes_gcm_128,
sizeof(*crypto_info_aes_gcm_128)))
rc = -EFAULT;
break;
}
default:
rc = -EINVAL;
}
out:
return rc;
}
static int do_tls_getsockopt(struct sock *sk, int optname,
char __user *optval, int __user *optlen)
{
int rc = 0;
switch (optname) {
case TLS_TX:
rc = do_tls_getsockopt_tx(sk, optval, optlen);
break;
default:
rc = -ENOPROTOOPT;
break;
}
return rc;
}
static int tls_getsockopt(struct sock *sk, int level, int optname,
char __user *optval, int __user *optlen)
{
struct tls_context *ctx = tls_get_ctx(sk);
if (level != SOL_TLS)
return ctx->getsockopt(sk, level, optname, optval, optlen);
return do_tls_getsockopt(sk, optname, optval, optlen);
}
static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
unsigned int optlen, int tx)
{
struct tls_crypto_info *crypto_info;
struct tls_context *ctx = tls_get_ctx(sk);
int rc = 0;
int conf;
if (!optval || (optlen < sizeof(*crypto_info))) {
rc = -EINVAL;
goto out;
}
if (tx)
crypto_info = &ctx->crypto_send.info;
else
crypto_info = &ctx->crypto_recv.info;
/* Currently we don't support set crypto info more than one time */
if (TLS_CRYPTO_INFO_READY(crypto_info)) {
rc = -EBUSY;
goto out;
}
rc = copy_from_user(crypto_info, optval, sizeof(*crypto_info));
if (rc) {
rc = -EFAULT;
goto err_crypto_info;
}
/* check version */
if (crypto_info->version != TLS_1_2_VERSION) {
rc = -ENOTSUPP;
goto err_crypto_info;
}
switch (crypto_info->cipher_type) {
case TLS_CIPHER_AES_GCM_128: {
if (optlen != sizeof(struct tls12_crypto_info_aes_gcm_128)) {
rc = -EINVAL;
goto err_crypto_info;
}
rc = copy_from_user(crypto_info + 1, optval + sizeof(*crypto_info),
optlen - sizeof(*crypto_info));
if (rc) {
rc = -EFAULT;
goto err_crypto_info;
}
break;
}
default:
rc = -EINVAL;
goto err_crypto_info;
}
if (tx) {
#ifdef CONFIG_TLS_DEVICE
rc = tls_set_device_offload(sk, ctx);
conf = TLS_HW;
if (rc) {
#else
{
#endif
rc = tls_set_sw_offload(sk, ctx, 1);
conf = TLS_SW;
}
} else {
#ifdef CONFIG_TLS_DEVICE
rc = tls_set_device_offload_rx(sk, ctx);
conf = TLS_HW;
if (rc) {
#else
{
#endif
rc = tls_set_sw_offload(sk, ctx, 0);
conf = TLS_SW;
}
}
if (rc)
goto err_crypto_info;
if (tx)
ctx->tx_conf = conf;
else
ctx->rx_conf = conf;
update_sk_prot(sk, ctx);
if (tx) {
ctx->sk_write_space = sk->sk_write_space;
sk->sk_write_space = tls_write_space;
} else {
sk->sk_socket->ops = &tls_sw_proto_ops;
}
goto out;
err_crypto_info:
memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
out:
return rc;
}
static int do_tls_setsockopt(struct sock *sk, int optname,
char __user *optval, unsigned int optlen)
{
int rc = 0;
switch (optname) {
case TLS_TX:
case TLS_RX:
lock_sock(sk);
rc = do_tls_setsockopt_conf(sk, optval, optlen,
optname == TLS_TX);
release_sock(sk);
break;
default:
rc = -ENOPROTOOPT;
break;
}
return rc;
}
static int tls_setsockopt(struct sock *sk, int level, int optname,
char __user *optval, unsigned int optlen)
{
struct tls_context *ctx = tls_get_ctx(sk);
if (level != SOL_TLS)
return ctx->setsockopt(sk, level, optname, optval, optlen);
return do_tls_setsockopt(sk, optname, optval, optlen);
}
static struct tls_context *create_ctx(struct sock *sk)
{
struct inet_connection_sock *icsk = inet_csk(sk);
struct tls_context *ctx;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return NULL;
icsk->icsk_ulp_data = ctx;
return ctx;
}
static int tls_hw_prot(struct sock *sk)
{
struct tls_context *ctx;
struct tls_device *dev;
int rc = 0;
mutex_lock(&device_mutex);
list_for_each_entry(dev, &device_list, dev_list) {
if (dev->feature && dev->feature(dev)) {
ctx = create_ctx(sk);
if (!ctx)
goto out;
ctx->hash = sk->sk_prot->hash;
ctx->unhash = sk->sk_prot->unhash;
ctx->sk_proto_close = sk->sk_prot->close;
ctx->rx_conf = TLS_HW_RECORD;
ctx->tx_conf = TLS_HW_RECORD;
update_sk_prot(sk, ctx);
rc = 1;
break;
}
}
out:
mutex_unlock(&device_mutex);
return rc;
}
static void tls_hw_unhash(struct sock *sk)
{
struct tls_context *ctx = tls_get_ctx(sk);
struct tls_device *dev;
mutex_lock(&device_mutex);
list_for_each_entry(dev, &device_list, dev_list) {
if (dev->unhash)
dev->unhash(dev, sk);
}
mutex_unlock(&device_mutex);
ctx->unhash(sk);
}
static int tls_hw_hash(struct sock *sk)
{
struct tls_context *ctx = tls_get_ctx(sk);
struct tls_device *dev;
int err;
err = ctx->hash(sk);
mutex_lock(&device_mutex);
list_for_each_entry(dev, &device_list, dev_list) {
if (dev->hash)
err |= dev->hash(dev, sk);
}
mutex_unlock(&device_mutex);
if (err)
tls_hw_unhash(sk);
return err;
}
static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
struct proto *base)
{
prot[TLS_BASE][TLS_BASE] = *base;
prot[TLS_BASE][TLS_BASE].setsockopt = tls_setsockopt;
prot[TLS_BASE][TLS_BASE].getsockopt = tls_getsockopt;
prot[TLS_BASE][TLS_BASE].close = tls_sk_proto_close;
prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
prot[TLS_SW][TLS_BASE].sendmsg = tls_sw_sendmsg;
prot[TLS_SW][TLS_BASE].sendpage = tls_sw_sendpage;
prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
prot[TLS_BASE][TLS_SW].recvmsg = tls_sw_recvmsg;
prot[TLS_BASE][TLS_SW].stream_memory_read = tls_sw_stream_read;
prot[TLS_BASE][TLS_SW].close = tls_sk_proto_close;
prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
prot[TLS_SW][TLS_SW].recvmsg = tls_sw_recvmsg;
prot[TLS_SW][TLS_SW].stream_memory_read = tls_sw_stream_read;
prot[TLS_SW][TLS_SW].close = tls_sk_proto_close;
#ifdef CONFIG_TLS_DEVICE
prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
prot[TLS_HW][TLS_BASE].sendmsg = tls_device_sendmsg;
prot[TLS_HW][TLS_BASE].sendpage = tls_device_sendpage;
prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
prot[TLS_HW][TLS_SW].sendmsg = tls_device_sendmsg;
prot[TLS_HW][TLS_SW].sendpage = tls_device_sendpage;
prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
#endif
prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
prot[TLS_HW_RECORD][TLS_HW_RECORD].hash = tls_hw_hash;
prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash = tls_hw_unhash;
prot[TLS_HW_RECORD][TLS_HW_RECORD].close = tls_sk_proto_close;
}
static int tls_init(struct sock *sk)
{
int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
struct tls_context *ctx;
int rc = 0;
if (tls_hw_prot(sk))
goto out;
/* The TLS ulp is currently supported only for TCP sockets
* in ESTABLISHED state.
* Supporting sockets in LISTEN state will require us
* to modify the accept implementation to clone rather then
* share the ulp context.
*/
if (sk->sk_state != TCP_ESTABLISHED)
return -ENOTSUPP;
/* allocate tls context */
ctx = create_ctx(sk);
if (!ctx) {
rc = -ENOMEM;
goto out;
}
ctx->setsockopt = sk->sk_prot->setsockopt;
ctx->getsockopt = sk->sk_prot->getsockopt;
ctx->sk_proto_close = sk->sk_prot->close;
/* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
if (ip_ver == TLSV6 &&
unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv6_prot))) {
mutex_lock(&tcpv6_prot_mutex);
if (likely(sk->sk_prot != saved_tcpv6_prot)) {
build_protos(tls_prots[TLSV6], sk->sk_prot);
smp_store_release(&saved_tcpv6_prot, sk->sk_prot);
}
mutex_unlock(&tcpv6_prot_mutex);
}
if (ip_ver == TLSV4 &&
unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv4_prot))) {
mutex_lock(&tcpv4_prot_mutex);
if (likely(sk->sk_prot != saved_tcpv4_prot)) {
build_protos(tls_prots[TLSV4], sk->sk_prot);
smp_store_release(&saved_tcpv4_prot, sk->sk_prot);
}
mutex_unlock(&tcpv4_prot_mutex);
}
ctx->tx_conf = TLS_BASE;
ctx->rx_conf = TLS_BASE;
update_sk_prot(sk, ctx);
out:
return rc;
}
void tls_register_device(struct tls_device *device)
{
mutex_lock(&device_mutex);
list_add_tail(&device->dev_list, &device_list);
mutex_unlock(&device_mutex);
}
EXPORT_SYMBOL(tls_register_device);
void tls_unregister_device(struct tls_device *device)
{
mutex_lock(&device_mutex);
list_del(&device->dev_list);
mutex_unlock(&device_mutex);
}
EXPORT_SYMBOL(tls_unregister_device);
static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
.name = "tls",
.owner = THIS_MODULE,
.init = tls_init,
};
static int __init tls_register(void)
{
tls_sw_proto_ops = inet_stream_ops;
tls_sw_proto_ops.splice_read = tls_sw_splice_read;
#ifdef CONFIG_TLS_DEVICE
tls_device_init();
#endif
tcp_register_ulp(&tcp_tls_ulp_ops);
return 0;
}
static void __exit tls_unregister(void)
{
tcp_unregister_ulp(&tcp_tls_ulp_ops);
#ifdef CONFIG_TLS_DEVICE
tls_device_cleanup();
#endif
}
module_init(tls_register);
module_exit(tls_unregister);