1/*
2 * Copyright (c) 2016 Tom Herbert <tom@herbertland.com>
3 * Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved.
4 * Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. All rights reserved.
5 *
6 * This software is available to you under a choice of one of two
7 * licenses.  You may choose to be licensed under the terms of the GNU
8 * General Public License (GPL) Version 2, available from the file
9 * COPYING in the main directory of this source tree, or the
10 * OpenIB.org BSD license below:
11 *
12 *     Redistribution and use in source and binary forms, with or
13 *     without modification, are permitted provided that the following
14 *     conditions are met:
15 *
16 *      - Redistributions of source code must retain the above
17 *        copyright notice, this list of conditions and the following
18 *        disclaimer.
19 *
20 *      - Redistributions in binary form must reproduce the above
21 *        copyright notice, this list of conditions and the following
22 *        disclaimer in the documentation and/or other materials
23 *        provided with the distribution.
24 *
25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32 * SOFTWARE.
33 */
34
35#ifndef _TLS_INT_H
36#define _TLS_INT_H
37
38#include <asm/byteorder.h>
39#include <linux/types.h>
40#include <linux/skmsg.h>
41#include <net/tls.h>
42#include <net/tls_prot.h>
43
44#define TLS_PAGE_ORDER	(min_t(unsigned int, PAGE_ALLOC_COSTLY_ORDER,	\
45			       TLS_MAX_PAYLOAD_SIZE >> PAGE_SHIFT))
46
47#define __TLS_INC_STATS(net, field)				\
48	__SNMP_INC_STATS((net)->mib.tls_statistics, field)
49#define TLS_INC_STATS(net, field)				\
50	SNMP_INC_STATS((net)->mib.tls_statistics, field)
51#define TLS_DEC_STATS(net, field)				\
52	SNMP_DEC_STATS((net)->mib.tls_statistics, field)
53
54struct tls_cipher_desc {
55	unsigned int nonce;
56	unsigned int iv;
57	unsigned int key;
58	unsigned int salt;
59	unsigned int tag;
60	unsigned int rec_seq;
61	unsigned int iv_offset;
62	unsigned int key_offset;
63	unsigned int salt_offset;
64	unsigned int rec_seq_offset;
65	char *cipher_name;
66	bool offloadable;
67	size_t crypto_info;
68};
69
70#define TLS_CIPHER_MIN TLS_CIPHER_AES_GCM_128
71#define TLS_CIPHER_MAX TLS_CIPHER_ARIA_GCM_256
72extern const struct tls_cipher_desc tls_cipher_desc[TLS_CIPHER_MAX + 1 - TLS_CIPHER_MIN];
73
74static inline const struct tls_cipher_desc *get_cipher_desc(u16 cipher_type)
75{
76	if (cipher_type < TLS_CIPHER_MIN || cipher_type > TLS_CIPHER_MAX)
77		return NULL;
78
79	return &tls_cipher_desc[cipher_type - TLS_CIPHER_MIN];
80}
81
82static inline char *crypto_info_iv(struct tls_crypto_info *crypto_info,
83				   const struct tls_cipher_desc *cipher_desc)
84{
85	return (char *)crypto_info + cipher_desc->iv_offset;
86}
87
88static inline char *crypto_info_key(struct tls_crypto_info *crypto_info,
89				    const struct tls_cipher_desc *cipher_desc)
90{
91	return (char *)crypto_info + cipher_desc->key_offset;
92}
93
94static inline char *crypto_info_salt(struct tls_crypto_info *crypto_info,
95				     const struct tls_cipher_desc *cipher_desc)
96{
97	return (char *)crypto_info + cipher_desc->salt_offset;
98}
99
100static inline char *crypto_info_rec_seq(struct tls_crypto_info *crypto_info,
101					const struct tls_cipher_desc *cipher_desc)
102{
103	return (char *)crypto_info + cipher_desc->rec_seq_offset;
104}
105
106
107/* TLS records are maintained in 'struct tls_rec'. It stores the memory pages
108 * allocated or mapped for each TLS record. After encryption, the records are
109 * stores in a linked list.
110 */
111struct tls_rec {
112	struct list_head list;
113	int tx_ready;
114	int tx_flags;
115
116	struct sk_msg msg_plaintext;
117	struct sk_msg msg_encrypted;
118
119	/* AAD | msg_plaintext.sg.data | sg_tag */
120	struct scatterlist sg_aead_in[2];
121	/* AAD | msg_encrypted.sg.data (data contains overhead for hdr & iv & tag) */
122	struct scatterlist sg_aead_out[2];
123
124	char content_type;
125	struct scatterlist sg_content_type;
126
127	struct sock *sk;
128
129	char aad_space[TLS_AAD_SPACE_SIZE];
130	u8 iv_data[TLS_MAX_IV_SIZE];
131	struct aead_request aead_req;
132	u8 aead_req_ctx[];
133};
134
135int __net_init tls_proc_init(struct net *net);
136void __net_exit tls_proc_fini(struct net *net);
137
138struct tls_context *tls_ctx_create(struct sock *sk);
139void tls_ctx_free(struct sock *sk, struct tls_context *ctx);
140void update_sk_prot(struct sock *sk, struct tls_context *ctx);
141
142int wait_on_pending_writer(struct sock *sk, long *timeo);
143void tls_err_abort(struct sock *sk, int err);
144
145int init_prot_info(struct tls_prot_info *prot,
146		   const struct tls_crypto_info *crypto_info,
147		   const struct tls_cipher_desc *cipher_desc);
148int tls_set_sw_offload(struct sock *sk, int tx);
149void tls_update_rx_zc_capable(struct tls_context *tls_ctx);
150void tls_sw_strparser_arm(struct sock *sk, struct tls_context *ctx);
151void tls_sw_strparser_done(struct tls_context *tls_ctx);
152int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size);
153void tls_sw_splice_eof(struct socket *sock);
154void tls_sw_cancel_work_tx(struct tls_context *tls_ctx);
155void tls_sw_release_resources_tx(struct sock *sk);
156void tls_sw_free_ctx_tx(struct tls_context *tls_ctx);
157void tls_sw_free_resources_rx(struct sock *sk);
158void tls_sw_release_resources_rx(struct sock *sk);
159void tls_sw_free_ctx_rx(struct tls_context *tls_ctx);
160int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
161		   int flags, int *addr_len);
162bool tls_sw_sock_is_readable(struct sock *sk);
163ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos,
164			   struct pipe_inode_info *pipe,
165			   size_t len, unsigned int flags);
166int tls_sw_read_sock(struct sock *sk, read_descriptor_t *desc,
167		     sk_read_actor_t read_actor);
168
169int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size);
170void tls_device_splice_eof(struct socket *sock);
171int tls_tx_records(struct sock *sk, int flags);
172
173void tls_sw_write_space(struct sock *sk, struct tls_context *ctx);
174void tls_device_write_space(struct sock *sk, struct tls_context *ctx);
175
176int tls_process_cmsg(struct sock *sk, struct msghdr *msg,
177		     unsigned char *record_type);
178int decrypt_skb(struct sock *sk, struct scatterlist *sgout);
179
180int tls_sw_fallback_init(struct sock *sk,
181			 struct tls_offload_context_tx *offload_ctx,
182			 struct tls_crypto_info *crypto_info);
183
184int tls_strp_dev_init(void);
185void tls_strp_dev_exit(void);
186
187void tls_strp_done(struct tls_strparser *strp);
188void tls_strp_stop(struct tls_strparser *strp);
189int tls_strp_init(struct tls_strparser *strp, struct sock *sk);
190void tls_strp_data_ready(struct tls_strparser *strp);
191
192void tls_strp_check_rcv(struct tls_strparser *strp);
193void tls_strp_msg_done(struct tls_strparser *strp);
194
195int tls_rx_msg_size(struct tls_strparser *strp, struct sk_buff *skb);
196void tls_rx_msg_ready(struct tls_strparser *strp);
197
198void tls_strp_msg_load(struct tls_strparser *strp, bool force_refresh);
199int tls_strp_msg_cow(struct tls_sw_context_rx *ctx);
200struct sk_buff *tls_strp_msg_detach(struct tls_sw_context_rx *ctx);
201int tls_strp_msg_hold(struct tls_strparser *strp, struct sk_buff_head *dst);
202
203static inline struct tls_msg *tls_msg(struct sk_buff *skb)
204{
205	struct sk_skb_cb *scb = (struct sk_skb_cb *)skb->cb;
206
207	return &scb->tls;
208}
209
210static inline struct sk_buff *tls_strp_msg(struct tls_sw_context_rx *ctx)
211{
212	DEBUG_NET_WARN_ON_ONCE(!ctx->strp.msg_ready || !ctx->strp.anchor->len);
213	return ctx->strp.anchor;
214}
215
216static inline bool tls_strp_msg_ready(struct tls_sw_context_rx *ctx)
217{
218	return READ_ONCE(ctx->strp.msg_ready);
219}
220
221static inline bool tls_strp_msg_mixed_decrypted(struct tls_sw_context_rx *ctx)
222{
223	return ctx->strp.mixed_decrypted;
224}
225
226#ifdef CONFIG_TLS_DEVICE
227int tls_device_init(void);
228void tls_device_cleanup(void);
229int tls_set_device_offload(struct sock *sk);
230void tls_device_free_resources_tx(struct sock *sk);
231int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx);
232void tls_device_offload_cleanup_rx(struct sock *sk);
233void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq);
234int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx);
235#else
236static inline int tls_device_init(void) { return 0; }
237static inline void tls_device_cleanup(void) {}
238
239static inline int
240tls_set_device_offload(struct sock *sk)
241{
242	return -EOPNOTSUPP;
243}
244
245static inline void tls_device_free_resources_tx(struct sock *sk) {}
246
247static inline int
248tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
249{
250	return -EOPNOTSUPP;
251}
252
253static inline void tls_device_offload_cleanup_rx(struct sock *sk) {}
254static inline void
255tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq) {}
256
257static inline int
258tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx)
259{
260	return 0;
261}
262#endif
263
264int tls_push_sg(struct sock *sk, struct tls_context *ctx,
265		struct scatterlist *sg, u16 first_offset,
266		int flags);
267int tls_push_partial_record(struct sock *sk, struct tls_context *ctx,
268			    int flags);
269void tls_free_partial_record(struct sock *sk, struct tls_context *ctx);
270
271static inline bool tls_is_partially_sent_record(struct tls_context *ctx)
272{
273	return !!ctx->partially_sent_record;
274}
275
276static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx)
277{
278	return tls_ctx->pending_open_record_frags;
279}
280
281static inline bool tls_bigint_increment(unsigned char *seq, int len)
282{
283	int i;
284
285	for (i = len - 1; i >= 0; i--) {
286		++seq[i];
287		if (seq[i] != 0)
288			break;
289	}
290
291	return (i == -1);
292}
293
294static inline void tls_bigint_subtract(unsigned char *seq, int  n)
295{
296	u64 rcd_sn;
297	__be64 *p;
298
299	BUILD_BUG_ON(TLS_MAX_REC_SEQ_SIZE != 8);
300
301	p = (__be64 *)seq;
302	rcd_sn = be64_to_cpu(*p);
303	*p = cpu_to_be64(rcd_sn - n);
304}
305
306static inline void
307tls_advance_record_sn(struct sock *sk, struct tls_prot_info *prot,
308		      struct cipher_context *ctx)
309{
310	if (tls_bigint_increment(ctx->rec_seq, prot->rec_seq_size))
311		tls_err_abort(sk, -EBADMSG);
312
313	if (prot->version != TLS_1_3_VERSION &&
314	    prot->cipher_type != TLS_CIPHER_CHACHA20_POLY1305)
315		tls_bigint_increment(ctx->iv + prot->salt_size,
316				     prot->iv_size);
317}
318
319static inline void
320tls_xor_iv_with_seq(struct tls_prot_info *prot, char *iv, char *seq)
321{
322	int i;
323
324	if (prot->version == TLS_1_3_VERSION ||
325	    prot->cipher_type == TLS_CIPHER_CHACHA20_POLY1305) {
326		for (i = 0; i < 8; i++)
327			iv[i + 4] ^= seq[i];
328	}
329}
330
331static inline void
332tls_fill_prepend(struct tls_context *ctx, char *buf, size_t plaintext_len,
333		 unsigned char record_type)
334{
335	struct tls_prot_info *prot = &ctx->prot_info;
336	size_t pkt_len, iv_size = prot->iv_size;
337
338	pkt_len = plaintext_len + prot->tag_size;
339	if (prot->version != TLS_1_3_VERSION &&
340	    prot->cipher_type != TLS_CIPHER_CHACHA20_POLY1305) {
341		pkt_len += iv_size;
342
343		memcpy(buf + TLS_NONCE_OFFSET,
344		       ctx->tx.iv + prot->salt_size, iv_size);
345	}
346
347	/* we cover nonce explicit here as well, so buf should be of
348	 * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE
349	 */
350	buf[0] = prot->version == TLS_1_3_VERSION ?
351		   TLS_RECORD_TYPE_DATA : record_type;
352	/* Note that VERSION must be TLS_1_2 for both TLS1.2 and TLS1.3 */
353	buf[1] = TLS_1_2_VERSION_MINOR;
354	buf[2] = TLS_1_2_VERSION_MAJOR;
355	/* we can use IV for nonce explicit according to spec */
356	buf[3] = pkt_len >> 8;
357	buf[4] = pkt_len & 0xFF;
358}
359
360static inline
361void tls_make_aad(char *buf, size_t size, char *record_sequence,
362		  unsigned char record_type, struct tls_prot_info *prot)
363{
364	if (prot->version != TLS_1_3_VERSION) {
365		memcpy(buf, record_sequence, prot->rec_seq_size);
366		buf += 8;
367	} else {
368		size += prot->tag_size;
369	}
370
371	buf[0] = prot->version == TLS_1_3_VERSION ?
372		  TLS_RECORD_TYPE_DATA : record_type;
373	buf[1] = TLS_1_2_VERSION_MAJOR;
374	buf[2] = TLS_1_2_VERSION_MINOR;
375	buf[3] = size >> 8;
376	buf[4] = size & 0xFF;
377}
378
379#endif
380