1/*
2 * Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved.
3 * Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. All rights reserved.
4 *
5 * This software is available to you under a choice of one of two
6 * licenses. You may choose to be licensed under the terms of the GNU
7 * General Public License (GPL) Version 2, available from the file
8 * COPYING in the main directory of this source tree, or the
9 * OpenIB.org BSD license below:
10 *
11 * Redistribution and use in source and binary forms, with or
12 * without modification, are permitted provided that the following
13 * conditions are met:
14 *
15 * - Redistributions of source code must retain the above
16 * copyright notice, this list of conditions and the following
17 * disclaimer.
18 *
19 * - Redistributions in binary form must reproduce the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer in the documentation and/or other materials
22 * provided with the distribution.
23 *
24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31 * SOFTWARE.
32 */
33
34#ifndef _TLS_OFFLOAD_H
35#define _TLS_OFFLOAD_H
36
37#include <linux/types.h>
38#include <asm/byteorder.h>
39#include <linux/crypto.h>
40#include <linux/socket.h>
41#include <linux/tcp.h>
42#include <linux/skmsg.h>
43
44#include <net/tcp.h>
45#include <net/strparser.h>
46#include <crypto/aead.h>
47#include <uapi/linux/tls.h>
48
49
50/* Maximum data size carried in a TLS record */
51#define TLS_MAX_PAYLOAD_SIZE ((size_t)1 << 14)
52
53#define TLS_HEADER_SIZE 5
54#define TLS_NONCE_OFFSET TLS_HEADER_SIZE
55
56#define TLS_CRYPTO_INFO_READY(info) ((info)->cipher_type)
57
58#define TLS_RECORD_TYPE_DATA 0x17
59
60#define TLS_AAD_SPACE_SIZE 13
61#define TLS_DEVICE_NAME_MAX 32
62
63/*
64 * This structure defines the routines for Inline TLS driver.
65 * The following routines are optional and filled with a
66 * null pointer if not defined.
67 *
68 * @name: Its the name of registered Inline tls device
69 * @dev_list: Inline tls device list
70 * int (*feature)(struct tls_device *device);
71 * Called to return Inline TLS driver capability
72 *
73 * int (*hash)(struct tls_device *device, struct sock *sk);
74 * This function sets Inline driver for listen and program
75 * device specific functioanlity as required
76 *
77 * void (*unhash)(struct tls_device *device, struct sock *sk);
78 * This function cleans listen state set by Inline TLS driver
79 *
80 * void (*release)(struct kref *kref);
81 * Release the registered device and allocated resources
82 * @kref: Number of reference to tls_device
83 */
84struct tls_device {
85 char name[TLS_DEVICE_NAME_MAX];
86 struct list_head dev_list;
87 int (*feature)(struct tls_device *device);
88 int (*hash)(struct tls_device *device, struct sock *sk);
89 void (*unhash)(struct tls_device *device, struct sock *sk);
90 void (*release)(struct kref *kref);
91 struct kref kref;
92};
93
94enum {
95 TLS_BASE,
96 TLS_SW,
97#ifdef CONFIG_TLS_DEVICE
98 TLS_HW,
99#endif
100 TLS_HW_RECORD,
101 TLS_NUM_CONFIG,
102};
103
104/* TLS records are maintained in 'struct tls_rec'. It stores the memory pages
105 * allocated or mapped for each TLS record. After encryption, the records are
106 * stores in a linked list.
107 */
108struct tls_rec {
109 struct list_head list;
110 int tx_ready;
111 int tx_flags;
112 int inplace_crypto;
113
114 struct sk_msg msg_plaintext;
115 struct sk_msg msg_encrypted;
116
117 /* AAD | msg_plaintext.sg.data | sg_tag */
118 struct scatterlist sg_aead_in[2];
119 /* AAD | msg_encrypted.sg.data (data contains overhead for hdr & iv & tag) */
120 struct scatterlist sg_aead_out[2];
121
122 char content_type;
123 struct scatterlist sg_content_type;
124
125 char aad_space[TLS_AAD_SPACE_SIZE];
126 u8 iv_data[TLS_CIPHER_AES_GCM_128_IV_SIZE +
127 TLS_CIPHER_AES_GCM_128_SALT_SIZE];
128 struct aead_request aead_req;
129 u8 aead_req_ctx[];
130};
131
132struct tls_msg {
133 struct strp_msg rxm;
134 u8 control;
135};
136
137struct tx_work {
138 struct delayed_work work;
139 struct sock *sk;
140};
141
142struct tls_sw_context_tx {
143 struct crypto_aead *aead_send;
144 struct crypto_wait async_wait;
145 struct tx_work tx_work;
146 struct tls_rec *open_rec;
147 struct list_head tx_list;
148 atomic_t encrypt_pending;
149 int async_notify;
150 int async_capable;
151
152#define BIT_TX_SCHEDULED 0
153 unsigned long tx_bitmask;
154};
155
156struct tls_sw_context_rx {
157 struct crypto_aead *aead_recv;
158 struct crypto_wait async_wait;
159 struct strparser strp;
160 struct sk_buff_head rx_list; /* list of decrypted 'data' records */
161 void (*saved_data_ready)(struct sock *sk);
162
163 struct sk_buff *recv_pkt;
164 u8 control;
165 int async_capable;
166 bool decrypted;
167 atomic_t decrypt_pending;
168 bool async_notify;
169};
170
171struct tls_record_info {
172 struct list_head list;
173 u32 end_seq;
174 int len;
175 int num_frags;
176 skb_frag_t frags[MAX_SKB_FRAGS];
177};
178
179struct tls_offload_context_tx {
180 struct crypto_aead *aead_send;
181 spinlock_t lock; /* protects records list */
182 struct list_head records_list;
183 struct tls_record_info *open_record;
184 struct tls_record_info *retransmit_hint;
185 u64 hint_record_sn;
186 u64 unacked_record_sn;
187
188 struct scatterlist sg_tx_data[MAX_SKB_FRAGS];
189 void (*sk_destruct)(struct sock *sk);
190 u8 driver_state[];
191 /* The TLS layer reserves room for driver specific state
192 * Currently the belief is that there is not enough
193 * driver specific state to justify another layer of indirection
194 */
195#define TLS_DRIVER_STATE_SIZE (max_t(size_t, 8, sizeof(void *)))
196};
197
198#define TLS_OFFLOAD_CONTEXT_SIZE_TX \
199 (ALIGN(sizeof(struct tls_offload_context_tx), sizeof(void *)) + \
200 TLS_DRIVER_STATE_SIZE)
201
202struct cipher_context {
203 char *iv;
204 char *rec_seq;
205};
206
207union tls_crypto_context {
208 struct tls_crypto_info info;
209 union {
210 struct tls12_crypto_info_aes_gcm_128 aes_gcm_128;
211 struct tls12_crypto_info_aes_gcm_256 aes_gcm_256;
212 };
213};
214
215struct tls_prot_info {
216 u16 version;
217 u16 cipher_type;
218 u16 prepend_size;
219 u16 tag_size;
220 u16 overhead_size;
221 u16 iv_size;
222 u16 rec_seq_size;
223 u16 aad_size;
224 u16 tail_size;
225};
226
227struct tls_context {
228 struct tls_prot_info prot_info;
229
230 union tls_crypto_context crypto_send;
231 union tls_crypto_context crypto_recv;
232
233 struct list_head list;
234 struct net_device *netdev;
235 refcount_t refcount;
236
237 void *priv_ctx_tx;
238 void *priv_ctx_rx;
239
240 u8 tx_conf:3;
241 u8 rx_conf:3;
242
243 struct cipher_context tx;
244 struct cipher_context rx;
245
246 struct scatterlist *partially_sent_record;
247 u16 partially_sent_offset;
248
249 unsigned long flags;
250 bool in_tcp_sendpages;
251 bool pending_open_record_frags;
252
253 int (*push_pending_record)(struct sock *sk, int flags);
254
255 void (*sk_write_space)(struct sock *sk);
256 void (*sk_destruct)(struct sock *sk);
257 void (*sk_proto_close)(struct sock *sk, long timeout);
258
259 int (*setsockopt)(struct sock *sk, int level,
260 int optname, char __user *optval,
261 unsigned int optlen);
262 int (*getsockopt)(struct sock *sk, int level,
263 int optname, char __user *optval,
264 int __user *optlen);
265 int (*hash)(struct sock *sk);
266 void (*unhash)(struct sock *sk);
267};
268
269struct tls_offload_context_rx {
270 /* sw must be the first member of tls_offload_context_rx */
271 struct tls_sw_context_rx sw;
272 atomic64_t resync_req;
273 u8 driver_state[];
274 /* The TLS layer reserves room for driver specific state
275 * Currently the belief is that there is not enough
276 * driver specific state to justify another layer of indirection
277 */
278};
279
280#define TLS_OFFLOAD_CONTEXT_SIZE_RX \
281 (ALIGN(sizeof(struct tls_offload_context_rx), sizeof(void *)) + \
282 TLS_DRIVER_STATE_SIZE)
283
284int wait_on_pending_writer(struct sock *sk, long *timeo);
285int tls_sk_query(struct sock *sk, int optname, char __user *optval,
286 int __user *optlen);
287int tls_sk_attach(struct sock *sk, int optname, char __user *optval,
288 unsigned int optlen);
289
290int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx);
291int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size);
292int tls_sw_sendpage(struct sock *sk, struct page *page,
293 int offset, size_t size, int flags);
294void tls_sw_close(struct sock *sk, long timeout);
295void tls_sw_free_resources_tx(struct sock *sk);
296void tls_sw_free_resources_rx(struct sock *sk);
297void tls_sw_release_resources_rx(struct sock *sk);
298int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
299 int nonblock, int flags, int *addr_len);
300bool tls_sw_stream_read(const struct sock *sk);
301ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos,
302 struct pipe_inode_info *pipe,
303 size_t len, unsigned int flags);
304
305int tls_set_device_offload(struct sock *sk, struct tls_context *ctx);
306int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size);
307int tls_device_sendpage(struct sock *sk, struct page *page,
308 int offset, size_t size, int flags);
309void tls_device_sk_destruct(struct sock *sk);
310void tls_device_init(void);
311void tls_device_cleanup(void);
312int tls_tx_records(struct sock *sk, int flags);
313
314struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
315 u32 seq, u64 *p_record_sn);
316
317static inline bool tls_record_is_start_marker(struct tls_record_info *rec)
318{
319 return rec->len == 0;
320}
321
322static inline u32 tls_record_start_seq(struct tls_record_info *rec)
323{
324 return rec->end_seq - rec->len;
325}
326
327void tls_sk_destruct(struct sock *sk, struct tls_context *ctx);
328int tls_push_sg(struct sock *sk, struct tls_context *ctx,
329 struct scatterlist *sg, u16 first_offset,
330 int flags);
331int tls_push_partial_record(struct sock *sk, struct tls_context *ctx,
332 int flags);
333
334static inline struct tls_msg *tls_msg(struct sk_buff *skb)
335{
336 return (struct tls_msg *)strp_msg(skb);
337}
338
339static inline bool tls_is_partially_sent_record(struct tls_context *ctx)
340{
341 return !!ctx->partially_sent_record;
342}
343
344static inline int tls_complete_pending_work(struct sock *sk,
345 struct tls_context *ctx,
346 int flags, long *timeo)
347{
348 int rc = 0;
349
350 if (unlikely(sk->sk_write_pending))
351 rc = wait_on_pending_writer(sk, timeo);
352
353 if (!rc && tls_is_partially_sent_record(ctx))
354 rc = tls_push_partial_record(sk, ctx, flags);
355
356 return rc;
357}
358
359static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx)
360{
361 return tls_ctx->pending_open_record_frags;
362}
363
364static inline bool is_tx_ready(struct tls_sw_context_tx *ctx)
365{
366 struct tls_rec *rec;
367
368 rec = list_first_entry(&ctx->tx_list, struct tls_rec, list);
369 if (!rec)
370 return false;
371
372 return READ_ONCE(rec->tx_ready);
373}
374
375struct sk_buff *
376tls_validate_xmit_skb(struct sock *sk, struct net_device *dev,
377 struct sk_buff *skb);
378
379static inline bool tls_is_sk_tx_device_offloaded(struct sock *sk)
380{
381#ifdef CONFIG_SOCK_VALIDATE_XMIT
382 return sk_fullsock(sk) &
383 (smp_load_acquire(&sk->sk_validate_xmit_skb) ==
384 &tls_validate_xmit_skb);
385#else
386 return false;
387#endif
388}
389
390static inline void tls_err_abort(struct sock *sk, int err)
391{
392 sk->sk_err = err;
393 sk->sk_error_report(sk);
394}
395
396static inline bool tls_bigint_increment(unsigned char *seq, int len)
397{
398 int i;
399
400 for (i = len - 1; i >= 0; i--) {
401 ++seq[i];
402 if (seq[i] != 0)
403 break;
404 }
405
406 return (i == -1);
407}
408
409static inline struct tls_context *tls_get_ctx(const struct sock *sk)
410{
411 struct inet_connection_sock *icsk = inet_csk(sk);
412
413 return icsk->icsk_ulp_data;
414}
415
416static inline void tls_advance_record_sn(struct sock *sk,
417 struct cipher_context *ctx,
418 int version)
419{
420 struct tls_context *tls_ctx = tls_get_ctx(sk);
421 struct tls_prot_info *prot = &tls_ctx->prot_info;
422
423 if (tls_bigint_increment(ctx->rec_seq, prot->rec_seq_size))
424 tls_err_abort(sk, EBADMSG);
425
426 if (version != TLS_1_3_VERSION) {
427 tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
428 prot->iv_size);
429 }
430}
431
432static inline void tls_fill_prepend(struct tls_context *ctx,
433 char *buf,
434 size_t plaintext_len,
435 unsigned char record_type,
436 int version)
437{
438 struct tls_prot_info *prot = &ctx->prot_info;
439 size_t pkt_len, iv_size = prot->iv_size;
440
441 pkt_len = plaintext_len + prot->tag_size;
442 if (version != TLS_1_3_VERSION) {
443 pkt_len += iv_size;
444
445 memcpy(buf + TLS_NONCE_OFFSET,
446 ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size);
447 }
448
449 /* we cover nonce explicit here as well, so buf should be of
450 * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE
451 */
452 buf[0] = version == TLS_1_3_VERSION ?
453 TLS_RECORD_TYPE_DATA : record_type;
454 /* Note that VERSION must be TLS_1_2 for both TLS1.2 and TLS1.3 */
455 buf[1] = TLS_1_2_VERSION_MINOR;
456 buf[2] = TLS_1_2_VERSION_MAJOR;
457 /* we can use IV for nonce explicit according to spec */
458 buf[3] = pkt_len >> 8;
459 buf[4] = pkt_len & 0xFF;
460}
461
462static inline void tls_make_aad(char *buf,
463 size_t size,
464 char *record_sequence,
465 int record_sequence_size,
466 unsigned char record_type,
467 int version)
468{
469 if (version != TLS_1_3_VERSION) {
470 memcpy(buf, record_sequence, record_sequence_size);
471 buf += 8;
472 } else {
473 size += TLS_CIPHER_AES_GCM_128_TAG_SIZE;
474 }
475
476 buf[0] = version == TLS_1_3_VERSION ?
477 TLS_RECORD_TYPE_DATA : record_type;
478 buf[1] = TLS_1_2_VERSION_MAJOR;
479 buf[2] = TLS_1_2_VERSION_MINOR;
480 buf[3] = size >> 8;
481 buf[4] = size & 0xFF;
482}
483
484static inline void xor_iv_with_seq(int version, char *iv, char *seq)
485{
486 int i;
487
488 if (version == TLS_1_3_VERSION) {
489 for (i = 0; i < 8; i++)
490 iv[i + 4] ^= seq[i];
491 }
492}
493
494
495static inline struct tls_sw_context_rx *tls_sw_ctx_rx(
496 const struct tls_context *tls_ctx)
497{
498 return (struct tls_sw_context_rx *)tls_ctx->priv_ctx_rx;
499}
500
501static inline struct tls_sw_context_tx *tls_sw_ctx_tx(
502 const struct tls_context *tls_ctx)
503{
504 return (struct tls_sw_context_tx *)tls_ctx->priv_ctx_tx;
505}
506
507static inline struct tls_offload_context_tx *
508tls_offload_ctx_tx(const struct tls_context *tls_ctx)
509{
510 return (struct tls_offload_context_tx *)tls_ctx->priv_ctx_tx;
511}
512
513static inline bool tls_sw_has_ctx_tx(const struct sock *sk)
514{
515 struct tls_context *ctx = tls_get_ctx(sk);
516
517 if (!ctx)
518 return false;
519 return !!tls_sw_ctx_tx(ctx);
520}
521
522void tls_sw_write_space(struct sock *sk, struct tls_context *ctx);
523void tls_device_write_space(struct sock *sk, struct tls_context *ctx);
524
525static inline struct tls_offload_context_rx *
526tls_offload_ctx_rx(const struct tls_context *tls_ctx)
527{
528 return (struct tls_offload_context_rx *)tls_ctx->priv_ctx_rx;
529}
530
531/* The TLS context is valid until sk_destruct is called */
532static inline void tls_offload_rx_resync_request(struct sock *sk, __be32 seq)
533{
534 struct tls_context *tls_ctx = tls_get_ctx(sk);
535 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);
536
537 atomic64_set(&rx_ctx->resync_req, ((((uint64_t)seq) << 32) | 1));
538}
539
540
541int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
542 unsigned char *record_type);
543void tls_register_device(struct tls_device *device);
544void tls_unregister_device(struct tls_device *device);
545int tls_device_decrypted(struct sock *sk, struct sk_buff *skb);
546int decrypt_skb(struct sock *sk, struct sk_buff *skb,
547 struct scatterlist *sgout);
548
549struct sk_buff *tls_validate_xmit_skb(struct sock *sk,
550 struct net_device *dev,
551 struct sk_buff *skb);
552
553int tls_sw_fallback_init(struct sock *sk,
554 struct tls_offload_context_tx *offload_ctx,
555 struct tls_crypto_info *crypto_info);
556
557int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx);
558
559void tls_device_offload_cleanup_rx(struct sock *sk);
560void handle_device_resync(struct sock *sk, u32 seq, u64 rcd_sn);
561
562#endif /* _TLS_OFFLOAD_H */
563