net/tls/tls_main.c - arm/linux - Git at Google

 /*
  * 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");

 static struct proto tls_base_prot;
 static struct proto tls_sw_prot;

 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;

 	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;
 			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);

 	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 (!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_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);

 	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++;
 		}
 	}
 	ctx->free_resources(sk);
 	kfree(ctx->rec_seq);
 	kfree(ctx->iv);

 	sk_proto_close = ctx->sk_proto_close;
 	kfree(ctx);

 	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;

 	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_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, tmp_crypto_info;
 	struct tls_context *ctx = tls_get_ctx(sk);
 	struct proto *prot = NULL;
 	int rc = 0;

 	if (!optval || (optlen < sizeof(*crypto_info))) {
 		rc = -EINVAL;
 		goto out;
 	}

 	rc = copy_from_user(&tmp_crypto_info, optval, sizeof(*crypto_info));
 	if (rc) {
 		rc = -EFAULT;
 		goto out;
 	}

 	/* check version */
 	if (tmp_crypto_info.version != TLS_1_2_VERSION) {
 		rc = -ENOTSUPP;
 		goto out;
 	}

 	/* get user crypto info */
 	crypto_info = &ctx->crypto_send;

 	/* Currently we don't support set crypto info more than one time */
 	if (TLS_CRYPTO_INFO_READY(crypto_info))
 		goto out;

 	switch (tmp_crypto_info.cipher_type) {
 	case TLS_CIPHER_AES_GCM_128: {
 		if (optlen != sizeof(struct tls12_crypto_info_aes_gcm_128)) {
 			rc = -EINVAL;
 			goto out;
 		}
 		rc = copy_from_user(
 		  crypto_info,
 		  optval,
 		  sizeof(struct tls12_crypto_info_aes_gcm_128));

 		if (rc) {
 			rc = -EFAULT;
 			goto err_crypto_info;
 		}
 		break;
 	}
 	default:
 		rc = -EINVAL;
 		goto out;
 	}

 	ctx->sk_write_space = sk->sk_write_space;
 	sk->sk_write_space = tls_write_space;

 	ctx->sk_proto_close = sk->sk_prot->close;

 	/* currently SW is default, we will have ethtool in future */
 	rc = tls_set_sw_offload(sk, ctx);
 	prot = &tls_sw_prot;
 	if (rc)
 		goto err_crypto_info;

 	sk->sk_prot = prot;
 	goto out;

 err_crypto_info:
 	memset(crypto_info, 0, sizeof(*crypto_info));
 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 int tls_init(struct sock *sk)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tls_context *ctx;
 	int rc = 0;

 	/* 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;
 	sk->sk_prot = &tls_base_prot;
 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)
 {
 	tls_base_prot			= tcp_prot;
 	tls_base_prot.setsockopt	= tls_setsockopt;
 	tls_base_prot.getsockopt	= tls_getsockopt;

 	tls_sw_prot			= tls_base_prot;
 	tls_sw_prot.sendmsg		= tls_sw_sendmsg;
 	tls_sw_prot.sendpage            = tls_sw_sendpage;
 	tls_sw_prot.close               = tls_sk_proto_close;

 	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);
	/*
	* 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");

	static struct proto tls_base_prot;
	static struct proto tls_sw_prot;

	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;

	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;
	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);

	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 (!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_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);

	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++;
	}
	}
	ctx->free_resources(sk);
	kfree(ctx->rec_seq);
	kfree(ctx->iv);

	sk_proto_close = ctx->sk_proto_close;
	kfree(ctx);

	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;

	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_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, tmp_crypto_info;
	struct tls_context *ctx = tls_get_ctx(sk);
	struct proto *prot = NULL;
	int rc = 0;

	if (!optval \|\| (optlen < sizeof(*crypto_info))) {
	rc = -EINVAL;
	goto out;
	}

	rc = copy_from_user(&tmp_crypto_info, optval, sizeof(*crypto_info));
	if (rc) {
	rc = -EFAULT;
	goto out;
	}

	/* check version */
	if (tmp_crypto_info.version != TLS_1_2_VERSION) {
	rc = -ENOTSUPP;
	goto out;
	}

	/* get user crypto info */
	crypto_info = &ctx->crypto_send;

	/* Currently we don't support set crypto info more than one time */
	if (TLS_CRYPTO_INFO_READY(crypto_info))
	goto out;

	switch (tmp_crypto_info.cipher_type) {
	case TLS_CIPHER_AES_GCM_128: {
	if (optlen != sizeof(struct tls12_crypto_info_aes_gcm_128)) {
	rc = -EINVAL;
	goto out;
	}
	rc = copy_from_user(
	crypto_info,
	optval,
	sizeof(struct tls12_crypto_info_aes_gcm_128));

	if (rc) {
	rc = -EFAULT;
	goto err_crypto_info;
	}
	break;
	}
	default:
	rc = -EINVAL;
	goto out;
	}

	ctx->sk_write_space = sk->sk_write_space;
	sk->sk_write_space = tls_write_space;

	ctx->sk_proto_close = sk->sk_prot->close;

	/* currently SW is default, we will have ethtool in future */
	rc = tls_set_sw_offload(sk, ctx);
	prot = &tls_sw_prot;
	if (rc)
	goto err_crypto_info;

	sk->sk_prot = prot;
	goto out;

	err_crypto_info:
	memset(crypto_info, 0, sizeof(*crypto_info));
	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 int tls_init(struct sock *sk)
	{
	struct inet_connection_sock *icsk = inet_csk(sk);
	struct tls_context *ctx;
	int rc = 0;

	/* 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;
	sk->sk_prot = &tls_base_prot;
	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)
	{
	tls_base_prot = tcp_prot;
	tls_base_prot.setsockopt = tls_setsockopt;
	tls_base_prot.getsockopt = tls_getsockopt;

	tls_sw_prot = tls_base_prot;
	tls_sw_prot.sendmsg = tls_sw_sendmsg;
	tls_sw_prot.sendpage = tls_sw_sendpage;
	tls_sw_prot.close = tls_sk_proto_close;

	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);