blob: e903bdd39b9f4d5c22842e0a4e8c2fea9ea65ed5 [file] [log] [blame]
/*
* 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 <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,
};
enum {
TLS_BASE_TX,
TLS_SW_TX,
TLS_NUM_CONFIG,
};
static struct proto *saved_tcpv6_prot;
static DEFINE_MUTEX(tcpv6_prot_mutex);
static struct proto tls_prots[TLS_NUM_PROTS][TLS_NUM_CONFIG];
static inline 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];
}
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;
}
clear_bit(TLS_PENDING_CLOSED_RECORD, &ctx->flags);
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_pending_closed_record(struct sock *sk, struct tls_context *ctx,
int flags, long *timeo)
{
struct scatterlist *sg;
u16 offset;
if (!tls_is_partially_sent_record(ctx))
return ctx->push_pending_record(sk, flags);
sg = ctx->partially_sent_record;
offset = ctx->partially_sent_offset;
ctx->partially_sent_record = NULL;
return tls_push_sg(sk, ctx, sg, offset, flags);
}
static void tls_write_space(struct sock *sk)
{
struct tls_context *ctx = tls_get_ctx(sk);
/* 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;
}
if (!sk->sk_write_pending && tls_is_pending_closed_record(ctx)) {
gfp_t sk_allocation = sk->sk_allocation;
int rc;
long timeo = 0;
sk->sk_allocation = GFP_ATOMIC;
rc = tls_push_pending_closed_record(sk, ctx,
MSG_DONTWAIT |
MSG_NOSIGNAL,
&timeo);
sk->sk_allocation = sk_allocation;
if (rc < 0)
return;
}
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));
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);
lock_sock(sk);
sk_proto_close = ctx->sk_proto_close;
if (ctx->tx_conf == TLS_BASE_TX) {
tls_ctx_free(ctx);
goto skip_tx_cleanup;
}
if (!tls_complete_pending_work(sk, ctx, 0, &timeo))
tls_handle_open_record(sk, 0);
if (ctx->partially_sent_record) {
struct scatterlist *sg = ctx->partially_sent_record;
while (1) {
put_page(sg_page(sg));
sk_mem_uncharge(sk, sg->length);
if (sg_is_last(sg))
break;
sg++;
}
}
kfree(ctx->rec_seq);
kfree(ctx->iv);
if (ctx->tx_conf == TLS_SW_TX) {
tls_sw_free_tx_resources(sk);
tls_ctx_free(ctx);
}
skip_tx_cleanup:
release_sock(sk);
sk_proto_close(sk, timeout);
}
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->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
TLS_CIPHER_AES_GCM_128_IV_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_tx(struct sock *sk, char __user *optval,
unsigned int optlen)
{
struct tls_crypto_info *crypto_info;
struct tls_context *ctx = tls_get_ctx(sk);
int rc = 0;
int tx_conf;
if (!optval || (optlen < sizeof(*crypto_info))) {
rc = -EINVAL;
goto out;
}
crypto_info = &ctx->crypto_send.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 out;
}
/* 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;
}
/* currently SW is default, we will have ethtool in future */
rc = tls_set_sw_offload(sk, ctx);
tx_conf = TLS_SW_TX;
if (rc)
goto err_crypto_info;
ctx->tx_conf = tx_conf;
update_sk_prot(sk, ctx);
ctx->sk_write_space = sk->sk_write_space;
sk->sk_write_space = tls_write_space;
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:
lock_sock(sk);
rc = do_tls_setsockopt_tx(sk, optval, optlen);
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 void build_protos(struct proto *prot, struct proto *base)
{
prot[TLS_BASE_TX] = *base;
prot[TLS_BASE_TX].setsockopt = tls_setsockopt;
prot[TLS_BASE_TX].getsockopt = tls_getsockopt;
prot[TLS_BASE_TX].close = tls_sk_proto_close;
prot[TLS_SW_TX] = prot[TLS_BASE_TX];
prot[TLS_SW_TX].sendmsg = tls_sw_sendmsg;
prot[TLS_SW_TX].sendpage = tls_sw_sendpage;
}
static int tls_init(struct sock *sk)
{
int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
struct inet_connection_sock *icsk = inet_csk(sk);
struct tls_context *ctx;
int rc = 0;
/* 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 = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx) {
rc = -ENOMEM;
goto out;
}
icsk->icsk_ulp_data = ctx;
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);
}
ctx->tx_conf = TLS_BASE_TX;
update_sk_prot(sk, ctx);
out:
return rc;
}
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)
{
build_protos(tls_prots[TLSV4], &tcp_prot);
tcp_register_ulp(&tcp_tls_ulp_ops);
return 0;
}
static void __exit tls_unregister(void)
{
tcp_unregister_ulp(&tcp_tls_ulp_ops);
}
module_init(tls_register);
module_exit(tls_unregister);