tls.h
/*
* 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.
*/
#ifndef _TLS_OFFLOAD_H
#define _TLS_OFFLOAD_H
#include <linux/types.h>
#include <asm/byteorder.h>
#include <linux/socket.h>
#include <linux/tcp.h>
#include <net/tcp.h>
#include <uapi/linux/tls.h>
/* Maximum data size carried in a TLS record */
#define TLS_MAX_PAYLOAD_SIZE ((size_t)1 << 14)
#define TLS_HEADER_SIZE 5
#define TLS_NONCE_OFFSET TLS_HEADER_SIZE
#define TLS_CRYPTO_INFO_READY(info) ((info)->cipher_type)
#define TLS_RECORD_TYPE_DATA 0x17
#define TLS_AAD_SPACE_SIZE 13
struct tls_sw_context {
struct crypto_aead *aead_send;
/* Sending context */
char aad_space[TLS_AAD_SPACE_SIZE];
unsigned int sg_plaintext_size;
int sg_plaintext_num_elem;
struct scatterlist sg_plaintext_data[MAX_SKB_FRAGS];
unsigned int sg_encrypted_size;
int sg_encrypted_num_elem;
struct scatterlist sg_encrypted_data[MAX_SKB_FRAGS];
/* AAD | sg_plaintext_data | sg_tag */
struct scatterlist sg_aead_in[2];
/* AAD | sg_encrypted_data (data contain overhead for hdr&iv&tag) */
struct scatterlist sg_aead_out[2];
};
enum {
TLS_PENDING_CLOSED_RECORD
};
struct tls_context {
union {
struct tls_crypto_info crypto_send;
struct tls12_crypto_info_aes_gcm_128 crypto_send_aes_gcm_128;
};
void *priv_ctx;
u8 tx_conf:2;
u16 prepend_size;
u16 tag_size;
u16 overhead_size;
u16 iv_size;
char *iv;
u16 rec_seq_size;
char *rec_seq;
struct scatterlist *partially_sent_record;
u16 partially_sent_offset;
unsigned long flags;
u16 pending_open_record_frags;
int (*push_pending_record)(struct sock *sk, int flags);
void (*sk_write_space)(struct sock *sk);
void (*sk_proto_close)(struct sock *sk, long timeout);
int (*setsockopt)(struct sock *sk, int level,
int optname, char __user *optval,
unsigned int optlen);
int (*getsockopt)(struct sock *sk, int level,
int optname, char __user *optval,
int __user *optlen);
};
int wait_on_pending_writer(struct sock *sk, long *timeo);
int tls_sk_query(struct sock *sk, int optname, char __user *optval,
int __user *optlen);
int tls_sk_attach(struct sock *sk, int optname, char __user *optval,
unsigned int optlen);
int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx);
int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size);
int tls_sw_sendpage(struct sock *sk, struct page *page,
int offset, size_t size, int flags);
void tls_sw_close(struct sock *sk, long timeout);
void tls_sw_free_tx_resources(struct sock *sk);
void tls_sk_destruct(struct sock *sk, struct tls_context *ctx);
void tls_icsk_clean_acked(struct sock *sk);
int tls_push_sg(struct sock *sk, struct tls_context *ctx,
struct scatterlist *sg, u16 first_offset,
int flags);
int tls_push_pending_closed_record(struct sock *sk, struct tls_context *ctx,
int flags, long *timeo);
static inline bool tls_is_pending_closed_record(struct tls_context *ctx)
{
return test_bit(TLS_PENDING_CLOSED_RECORD, &ctx->flags);
}
static inline int tls_complete_pending_work(struct sock *sk,
struct tls_context *ctx,
int flags, long *timeo)
{
int rc = 0;
if (unlikely(sk->sk_write_pending))
rc = wait_on_pending_writer(sk, timeo);
if (!rc && tls_is_pending_closed_record(ctx))
rc = tls_push_pending_closed_record(sk, ctx, flags, timeo);
return rc;
}
static inline bool tls_is_partially_sent_record(struct tls_context *ctx)
{
return !!ctx->partially_sent_record;
}
static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx)
{
return tls_ctx->pending_open_record_frags;
}
static inline void tls_err_abort(struct sock *sk)
{
sk->sk_err = -EBADMSG;
sk->sk_error_report(sk);
}
static inline bool tls_bigint_increment(unsigned char *seq, int len)
{
int i;
for (i = len - 1; i >= 0; i--) {
++seq[i];
if (seq[i] != 0)
break;
}
return (i == -1);
}
static inline void tls_advance_record_sn(struct sock *sk,
struct tls_context *ctx)
{
if (tls_bigint_increment(ctx->rec_seq, ctx->rec_seq_size))
tls_err_abort(sk);
tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
ctx->iv_size);
}
static inline void tls_fill_prepend(struct tls_context *ctx,
char *buf,
size_t plaintext_len,
unsigned char record_type)
{
size_t pkt_len, iv_size = ctx->iv_size;
pkt_len = plaintext_len + iv_size + ctx->tag_size;
/* we cover nonce explicit here as well, so buf should be of
* size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE
*/
buf[0] = record_type;
buf[1] = TLS_VERSION_MINOR(ctx->crypto_send.version);
buf[2] = TLS_VERSION_MAJOR(ctx->crypto_send.version);
/* we can use IV for nonce explicit according to spec */
buf[3] = pkt_len >> 8;
buf[4] = pkt_len & 0xFF;
memcpy(buf + TLS_NONCE_OFFSET,
ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size);
}
static inline void tls_make_aad(char *buf,
size_t size,
char *record_sequence,
int record_sequence_size,
unsigned char record_type)
{
memcpy(buf, record_sequence, record_sequence_size);
buf[8] = record_type;
buf[9] = TLS_1_2_VERSION_MAJOR;
buf[10] = TLS_1_2_VERSION_MINOR;
buf[11] = size >> 8;
buf[12] = size & 0xFF;
}
static inline struct tls_context *tls_get_ctx(const struct sock *sk)
{
struct inet_connection_sock *icsk = inet_csk(sk);
return icsk->icsk_ulp_data;
}
static inline struct tls_sw_context *tls_sw_ctx(
const struct tls_context *tls_ctx)
{
return (struct tls_sw_context *)tls_ctx->priv_ctx;
}
static inline struct tls_offload_context *tls_offload_ctx(
const struct tls_context *tls_ctx)
{
return (struct tls_offload_context *)tls_ctx->priv_ctx;
}
int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
unsigned char *record_type);
#endif /* _TLS_OFFLOAD_H */