xref: /openbsd-src/lib/libssl/tls13_internal.h (revision 25c4e8bd056e974b28f4a0ffd39d76c190a56013)
1 /* $OpenBSD: tls13_internal.h,v 1.99 2022/07/20 06:32:24 jsing Exp $ */
2 /*
3  * Copyright (c) 2018 Bob Beck <beck@openbsd.org>
4  * Copyright (c) 2018 Theo Buehler <tb@openbsd.org>
5  * Copyright (c) 2018, 2019 Joel Sing <jsing@openbsd.org>
6  *
7  * Permission to use, copy, modify, and/or distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
14  * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
16  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
17  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #ifndef HEADER_TLS13_INTERNAL_H
21 #define HEADER_TLS13_INTERNAL_H
22 
23 #include <openssl/evp.h>
24 #include <openssl/ssl.h>
25 
26 #include "bytestring.h"
27 #include "tls_internal.h"
28 
29 __BEGIN_HIDDEN_DECLS
30 
31 #define TLS13_HS_CLIENT			1
32 #define TLS13_HS_SERVER			2
33 
34 #define TLS13_IO_SUCCESS		 1
35 #define TLS13_IO_EOF			 0
36 #define TLS13_IO_FAILURE		-1
37 #define TLS13_IO_ALERT			-2
38 #define TLS13_IO_WANT_POLLIN		-3
39 #define TLS13_IO_WANT_POLLOUT		-4
40 #define TLS13_IO_WANT_RETRY		-5 /* Retry the previous call immediately. */
41 #define TLS13_IO_USE_LEGACY		-6
42 #define TLS13_IO_RECORD_VERSION		-7
43 #define TLS13_IO_RECORD_OVERFLOW	-8
44 
45 #define TLS13_ERR_VERIFY_FAILED		16
46 #define TLS13_ERR_HRR_FAILED		17
47 #define TLS13_ERR_TRAILING_DATA		18
48 #define TLS13_ERR_NO_SHARED_CIPHER	19
49 #define TLS13_ERR_NO_CERTIFICATE	20
50 #define TLS13_ERR_NO_PEER_CERTIFICATE	21
51 
52 #define TLS13_ALERT_LEVEL_WARNING			1
53 #define TLS13_ALERT_LEVEL_FATAL				2
54 
55 #define TLS13_ALERT_CLOSE_NOTIFY			0
56 #define TLS13_ALERT_UNEXPECTED_MESSAGE			10
57 #define TLS13_ALERT_BAD_RECORD_MAC			20
58 #define TLS13_ALERT_RECORD_OVERFLOW			22
59 #define TLS13_ALERT_HANDSHAKE_FAILURE			40
60 #define TLS13_ALERT_BAD_CERTIFICATE			42
61 #define TLS13_ALERT_UNSUPPORTED_CERTIFICATE		43
62 #define TLS13_ALERT_CERTIFICATE_REVOKED			44
63 #define TLS13_ALERT_CERTIFICATE_EXPIRED			45
64 #define TLS13_ALERT_CERTIFICATE_UNKNOWN			46
65 #define TLS13_ALERT_ILLEGAL_PARAMETER			47
66 #define TLS13_ALERT_UNKNOWN_CA				48
67 #define TLS13_ALERT_ACCESS_DENIED			49
68 #define TLS13_ALERT_DECODE_ERROR			50
69 #define TLS13_ALERT_DECRYPT_ERROR			51
70 #define TLS13_ALERT_PROTOCOL_VERSION			70
71 #define TLS13_ALERT_INSUFFICIENT_SECURITY		71
72 #define TLS13_ALERT_INTERNAL_ERROR			80
73 #define TLS13_ALERT_INAPPROPRIATE_FALLBACK		86
74 #define TLS13_ALERT_USER_CANCELED			90
75 #define TLS13_ALERT_MISSING_EXTENSION			109
76 #define TLS13_ALERT_UNSUPPORTED_EXTENSION		110
77 #define TLS13_ALERT_UNRECOGNIZED_NAME			112
78 #define TLS13_ALERT_BAD_CERTIFICATE_STATUS_RESPONSE	113
79 #define TLS13_ALERT_UNKNOWN_PSK_IDENTITY		115
80 #define TLS13_ALERT_CERTIFICATE_REQUIRED		116
81 #define TLS13_ALERT_NO_APPLICATION_PROTOCOL		120
82 
83 #define TLS13_INFO_HANDSHAKE_STARTED			SSL_CB_HANDSHAKE_START
84 #define TLS13_INFO_HANDSHAKE_COMPLETED			SSL_CB_HANDSHAKE_DONE
85 #define TLS13_INFO_ACCEPT_LOOP				SSL_CB_ACCEPT_LOOP
86 #define TLS13_INFO_CONNECT_LOOP				SSL_CB_CONNECT_LOOP
87 #define TLS13_INFO_ACCEPT_EXIT				SSL_CB_ACCEPT_EXIT
88 #define TLS13_INFO_CONNECT_EXIT				SSL_CB_CONNECT_EXIT
89 
90 typedef void (*tls13_alert_cb)(uint8_t _alert_desc, void *_cb_arg);
91 typedef ssize_t (*tls13_phh_recv_cb)(void *_cb_arg);
92 typedef void (*tls13_phh_sent_cb)(void *_cb_arg);
93 typedef void (*tls13_handshake_message_cb)(void *_cb_arg);
94 typedef void (*tls13_info_cb)(void *_cb_arg, int _state, int _ret);
95 typedef int (*tls13_ocsp_status_cb)(void *_cb_arg);
96 
97 /*
98  * PSK support.
99  */
100 
101 /*
102  * Known PskKeyExchangeMode values.
103  * https://www.iana.org/assignments/tls-parameters/#tls-pskkeyexchangemode
104  */
105 #define TLS13_PSK_KE					0
106 #define TLS13_PSK_DHE_KE				1
107 
108 /*
109  * Secrets.
110  */
111 struct tls13_secret {
112 	uint8_t *data;
113 	size_t len;
114 };
115 
116 /* RFC 8446 Section 7.1  Page 92 */
117 struct tls13_secrets {
118 	const EVP_MD *digest;
119 	int resumption;
120 	int init_done;
121 	int early_done;
122 	int handshake_done;
123 	int schedule_done;
124 	int insecure; /* Set by tests */
125 	struct tls13_secret zeros;
126 	struct tls13_secret empty_hash;
127 	struct tls13_secret extracted_early;
128 	struct tls13_secret binder_key;
129 	struct tls13_secret client_early_traffic;
130 	struct tls13_secret early_exporter_master;
131 	struct tls13_secret derived_early;
132 	struct tls13_secret extracted_handshake;
133 	struct tls13_secret client_handshake_traffic;
134 	struct tls13_secret server_handshake_traffic;
135 	struct tls13_secret derived_handshake;
136 	struct tls13_secret extracted_master;
137 	struct tls13_secret client_application_traffic;
138 	struct tls13_secret server_application_traffic;
139 	struct tls13_secret exporter_master;
140 	struct tls13_secret resumption_master;
141 };
142 
143 int tls13_secret_init(struct tls13_secret *secret, size_t len);
144 void tls13_secret_cleanup(struct tls13_secret *secret);
145 struct tls13_secrets *tls13_secrets_create(const EVP_MD *digest,
146     int resumption);
147 void tls13_secrets_destroy(struct tls13_secrets *secrets);
148 
149 int tls13_hkdf_expand_label(struct tls13_secret *out, const EVP_MD *digest,
150     const struct tls13_secret *secret, const char *label,
151     const struct tls13_secret *context);
152 int tls13_hkdf_expand_label_with_length(struct tls13_secret *out,
153     const EVP_MD *digest, const struct tls13_secret *secret,
154     const uint8_t *label, size_t label_len, const struct tls13_secret *context);
155 
156 int tls13_derive_secret(struct tls13_secret *out, const EVP_MD *digest,
157     const struct tls13_secret *secret, const char *label,
158     const struct tls13_secret *context);
159 int tls13_derive_secret_with_label_length(struct tls13_secret *out,
160     const EVP_MD *digest, const struct tls13_secret *secret,
161     const uint8_t *label, size_t label_len, const struct tls13_secret *context);
162 
163 int tls13_derive_early_secrets(struct tls13_secrets *secrets, uint8_t *psk,
164     size_t psk_len, const struct tls13_secret *context);
165 int tls13_derive_handshake_secrets(struct tls13_secrets *secrets,
166     const uint8_t *ecdhe, size_t ecdhe_len, const struct tls13_secret *context);
167 int tls13_derive_application_secrets(struct tls13_secrets *secrets,
168     const struct tls13_secret *context);
169 int tls13_update_client_traffic_secret(struct tls13_secrets *secrets);
170 int tls13_update_server_traffic_secret(struct tls13_secrets *secrets);
171 
172 /*
173  * Record Layer.
174  */
175 struct tls13_record_layer;
176 
177 struct tls13_record_layer_callbacks {
178 	tls_read_cb wire_read;
179 	tls_write_cb wire_write;
180 	tls_flush_cb wire_flush;
181 	tls13_alert_cb alert_recv;
182 	tls13_alert_cb alert_sent;
183 	tls13_phh_recv_cb phh_recv;
184 	tls13_phh_sent_cb phh_sent;
185 };
186 
187 struct tls13_record_layer *tls13_record_layer_new(
188     const struct tls13_record_layer_callbacks *callbacks, void *cb_arg);
189 void tls13_record_layer_free(struct tls13_record_layer *rl);
190 void tls13_record_layer_allow_ccs(struct tls13_record_layer *rl, int allow);
191 void tls13_record_layer_allow_legacy_alerts(struct tls13_record_layer *rl, int allow);
192 void tls13_record_layer_rcontent(struct tls13_record_layer *rl, CBS *cbs);
193 void tls13_record_layer_set_aead(struct tls13_record_layer *rl,
194     const EVP_AEAD *aead);
195 void tls13_record_layer_set_hash(struct tls13_record_layer *rl,
196     const EVP_MD *hash);
197 void tls13_record_layer_set_legacy_version(struct tls13_record_layer *rl,
198     uint16_t version);
199 void tls13_record_layer_set_retry_after_phh(struct tls13_record_layer *rl, int retry);
200 void tls13_record_layer_handshake_completed(struct tls13_record_layer *rl);
201 int tls13_record_layer_set_read_traffic_key(struct tls13_record_layer *rl,
202     struct tls13_secret *read_key);
203 int tls13_record_layer_set_write_traffic_key(struct tls13_record_layer *rl,
204     struct tls13_secret *write_key);
205 ssize_t tls13_record_layer_send_pending(struct tls13_record_layer *rl);
206 ssize_t tls13_record_layer_phh(struct tls13_record_layer *rl, CBS *cbs);
207 ssize_t tls13_record_layer_flush(struct tls13_record_layer *rl);
208 
209 ssize_t tls13_read_handshake_data(struct tls13_record_layer *rl, uint8_t *buf, size_t n);
210 ssize_t tls13_write_handshake_data(struct tls13_record_layer *rl, const uint8_t *buf,
211     size_t n);
212 ssize_t tls13_pending_application_data(struct tls13_record_layer *rl);
213 ssize_t tls13_peek_application_data(struct tls13_record_layer *rl, uint8_t *buf, size_t n);
214 ssize_t tls13_read_application_data(struct tls13_record_layer *rl, uint8_t *buf, size_t n);
215 ssize_t tls13_write_application_data(struct tls13_record_layer *rl, const uint8_t *buf,
216     size_t n);
217 
218 ssize_t tls13_send_alert(struct tls13_record_layer *rl, uint8_t alert_desc);
219 ssize_t tls13_send_dummy_ccs(struct tls13_record_layer *rl);
220 
221 /*
222  * Handshake Messages.
223  */
224 struct tls13_handshake_msg;
225 
226 struct tls13_handshake_msg *tls13_handshake_msg_new(void);
227 void tls13_handshake_msg_free(struct tls13_handshake_msg *msg);
228 void tls13_handshake_msg_data(struct tls13_handshake_msg *msg, CBS *cbs);
229 uint8_t tls13_handshake_msg_type(struct tls13_handshake_msg *msg);
230 int tls13_handshake_msg_content(struct tls13_handshake_msg *msg, CBS *cbs);
231 int tls13_handshake_msg_start(struct tls13_handshake_msg *msg, CBB *body,
232     uint8_t msg_type);
233 int tls13_handshake_msg_finish(struct tls13_handshake_msg *msg);
234 int tls13_handshake_msg_recv(struct tls13_handshake_msg *msg,
235     struct tls13_record_layer *rl);
236 int tls13_handshake_msg_send(struct tls13_handshake_msg *msg,
237     struct tls13_record_layer *rl);
238 
239 struct tls13_handshake_stage {
240 	uint8_t	hs_type;
241 	uint8_t	message_number;
242 };
243 
244 struct ssl_handshake_tls13_st;
245 
246 struct tls13_error {
247 	int code;
248 	int subcode;
249 	int errnum;
250 	const char *file;
251 	int line;
252 	char *msg;
253 };
254 
255 struct tls13_ctx {
256 	struct tls13_error error;
257 
258 	SSL *ssl;
259 	struct ssl_handshake_st *hs;
260 	uint8_t	mode;
261 	struct tls13_handshake_stage handshake_stage;
262 	int handshake_started;
263 	int handshake_completed;
264 	int need_flush;
265 	int middlebox_compat;
266 	int send_dummy_ccs;
267 	int send_dummy_ccs_after;
268 
269 	int close_notify_sent;
270 	int close_notify_recv;
271 
272 	const EVP_AEAD *aead;
273 	const EVP_MD *hash;
274 
275 	struct tls13_record_layer *rl;
276 	struct tls13_handshake_msg *hs_msg;
277 	uint8_t key_update_request;
278 	uint8_t alert;
279 	int phh_count;
280 	time_t phh_last_seen;
281 
282 	tls13_handshake_message_cb handshake_message_sent_cb;
283 	tls13_handshake_message_cb handshake_message_recv_cb;
284 	tls13_info_cb info_cb;
285 	tls13_ocsp_status_cb ocsp_status_recv_cb;
286 };
287 #ifndef TLS13_PHH_LIMIT_TIME
288 #define TLS13_PHH_LIMIT_TIME 3600
289 #endif
290 #ifndef TLS13_PHH_LIMIT
291 #define TLS13_PHH_LIMIT 100
292 #endif
293 
294 struct tls13_ctx *tls13_ctx_new(int mode, SSL *ssl);
295 void tls13_ctx_free(struct tls13_ctx *ctx);
296 
297 const EVP_AEAD *tls13_cipher_aead(const SSL_CIPHER *cipher);
298 const EVP_MD *tls13_cipher_hash(const SSL_CIPHER *cipher);
299 
300 /*
301  * Legacy interfaces.
302  */
303 int tls13_use_legacy_client(struct tls13_ctx *ctx);
304 int tls13_use_legacy_server(struct tls13_ctx *ctx);
305 int tls13_legacy_accept(SSL *ssl);
306 int tls13_legacy_connect(SSL *ssl);
307 int tls13_legacy_return_code(SSL *ssl, ssize_t ret);
308 ssize_t tls13_legacy_wire_read_cb(void *buf, size_t n, void *arg);
309 ssize_t tls13_legacy_wire_write_cb(const void *buf, size_t n, void *arg);
310 ssize_t tls13_legacy_wire_flush_cb(void *arg);
311 int tls13_legacy_pending(const SSL *ssl);
312 int tls13_legacy_read_bytes(SSL *ssl, int type, unsigned char *buf, int len,
313     int peek);
314 int tls13_legacy_write_bytes(SSL *ssl, int type, const void *buf, int len);
315 int tls13_legacy_shutdown(SSL *ssl);
316 int tls13_legacy_servername_process(struct tls13_ctx *ctx, uint8_t *alert);
317 
318 /*
319  * Message Types - RFC 8446, Section B.3.
320  *
321  * Values listed as "_RESERVED" were used in previous versions of TLS and are
322  * listed here for completeness.  TLS 1.3 implementations MUST NOT send them but
323  * might receive them from older TLS implementations.
324  */
325 #define	TLS13_MT_HELLO_REQUEST_RESERVED		0
326 #define	TLS13_MT_CLIENT_HELLO			1
327 #define	TLS13_MT_SERVER_HELLO			2
328 #define	TLS13_MT_HELLO_VERIFY_REQUEST_RESERVED	3
329 #define	TLS13_MT_NEW_SESSION_TICKET		4
330 #define	TLS13_MT_END_OF_EARLY_DATA		5
331 #define	TLS13_MT_HELLO_RETRY_REQUEST_RESERVED	6
332 #define	TLS13_MT_ENCRYPTED_EXTENSIONS		8
333 #define	TLS13_MT_CERTIFICATE			11
334 #define	TLS13_MT_SERVER_KEY_EXCHANGE_RESERVED	12
335 #define	TLS13_MT_CERTIFICATE_REQUEST		13
336 #define	TLS13_MT_SERVER_HELLO_DONE_RESERVED	14
337 #define	TLS13_MT_CERTIFICATE_VERIFY		15
338 #define	TLS13_MT_CLIENT_KEY_EXCHANGE_RESERVED	16
339 #define	TLS13_MT_FINISHED			20
340 #define	TLS13_MT_CERTIFICATE_URL_RESERVED	21
341 #define	TLS13_MT_CERTIFICATE_STATUS_RESERVED	22
342 #define	TLS13_MT_SUPPLEMENTAL_DATA_RESERVED	23
343 #define	TLS13_MT_KEY_UPDATE			24
344 #define	TLS13_MT_MESSAGE_HASH			254
345 
346 int tls13_handshake_msg_record(struct tls13_ctx *ctx);
347 int tls13_handshake_perform(struct tls13_ctx *ctx);
348 
349 int tls13_client_init(struct tls13_ctx *ctx);
350 int tls13_server_init(struct tls13_ctx *ctx);
351 int tls13_client_connect(struct tls13_ctx *ctx);
352 int tls13_server_accept(struct tls13_ctx *ctx);
353 
354 int tls13_client_hello_send(struct tls13_ctx *ctx, CBB *cbb);
355 int tls13_client_hello_sent(struct tls13_ctx *ctx);
356 int tls13_client_hello_recv(struct tls13_ctx *ctx, CBS *cbs);
357 int tls13_client_hello_retry_send(struct tls13_ctx *ctx, CBB *cbb);
358 int tls13_client_hello_retry_recv(struct tls13_ctx *ctx, CBS *cbs);
359 int tls13_client_end_of_early_data_send(struct tls13_ctx *ctx, CBB *cbb);
360 int tls13_client_end_of_early_data_recv(struct tls13_ctx *ctx, CBS *cbs);
361 int tls13_client_certificate_send(struct tls13_ctx *ctx, CBB *cbb);
362 int tls13_client_certificate_recv(struct tls13_ctx *ctx, CBS *cbs);
363 int tls13_client_certificate_verify_send(struct tls13_ctx *ctx, CBB *cbb);
364 int tls13_client_certificate_verify_recv(struct tls13_ctx *ctx, CBS *cbs);
365 int tls13_client_finished_recv(struct tls13_ctx *ctx, CBS *cbs);
366 int tls13_client_finished_send(struct tls13_ctx *ctx, CBB *cbb);
367 int tls13_client_finished_sent(struct tls13_ctx *ctx);
368 int tls13_server_hello_recv(struct tls13_ctx *ctx, CBS *cbs);
369 int tls13_server_hello_send(struct tls13_ctx *ctx, CBB *cbb);
370 int tls13_server_hello_sent(struct tls13_ctx *ctx);
371 int tls13_server_hello_retry_request_recv(struct tls13_ctx *ctx, CBS *cbs);
372 int tls13_server_hello_retry_request_send(struct tls13_ctx *ctx, CBB *cbb);
373 int tls13_server_hello_retry_request_sent(struct tls13_ctx *ctx);
374 int tls13_server_encrypted_extensions_recv(struct tls13_ctx *ctx, CBS *cbs);
375 int tls13_server_encrypted_extensions_send(struct tls13_ctx *ctx, CBB *cbb);
376 int tls13_server_certificate_recv(struct tls13_ctx *ctx, CBS *cbs);
377 int tls13_server_certificate_send(struct tls13_ctx *ctx, CBB *cbb);
378 int tls13_server_certificate_request_recv(struct tls13_ctx *ctx, CBS *cbs);
379 int tls13_server_certificate_request_send(struct tls13_ctx *ctx, CBB *cbb);
380 int tls13_server_certificate_verify_send(struct tls13_ctx *ctx, CBB *cbb);
381 int tls13_server_certificate_verify_recv(struct tls13_ctx *ctx, CBS *cbs);
382 int tls13_server_finished_recv(struct tls13_ctx *ctx, CBS *cbs);
383 int tls13_server_finished_send(struct tls13_ctx *ctx, CBB *cbb);
384 int tls13_server_finished_sent(struct tls13_ctx *ctx);
385 
386 void tls13_error_clear(struct tls13_error *error);
387 int tls13_cert_add(struct tls13_ctx *ctx, CBB *cbb, X509 *cert,
388     int(*build_extensions)(SSL *s, uint16_t msg_type, CBB *cbb));
389 
390 int tls13_synthetic_handshake_message(struct tls13_ctx *ctx);
391 int tls13_clienthello_hash_init(struct tls13_ctx *ctx);
392 void tls13_clienthello_hash_clear(struct ssl_handshake_tls13_st *hs);
393 int tls13_clienthello_hash_update_bytes(struct tls13_ctx *ctx, void *data,
394     size_t len);
395 int tls13_clienthello_hash_update(struct tls13_ctx *ctx, CBS *cbs);
396 int tls13_clienthello_hash_finalize(struct tls13_ctx *ctx);
397 int tls13_clienthello_hash_validate(struct tls13_ctx *ctx);
398 
399 int tls13_error_set(struct tls13_error *error, int code, int subcode,
400     const char *file, int line, const char *fmt, ...);
401 int tls13_error_setx(struct tls13_error *error, int code, int subcode,
402     const char *file, int line, const char *fmt, ...);
403 
404 #define tls13_set_error(ctx, code, subcode, fmt, ...) \
405 	tls13_error_set(&(ctx)->error, (code), (subcode), __FILE__, __LINE__, \
406 	    (fmt), __VA_ARGS__)
407 #define tls13_set_errorx(ctx, code, subcode, fmt, ...) \
408 	tls13_error_setx(&(ctx)->error, (code), (subcode), __FILE__, __LINE__, \
409 	    (fmt), __VA_ARGS__)
410 
411 int tls13_exporter(struct tls13_ctx *ctx, const uint8_t *label, size_t label_len,
412     const uint8_t *context_value, size_t context_value_len, uint8_t *out,
413     size_t out_len);
414 
415 extern const uint8_t tls13_downgrade_12[8];
416 extern const uint8_t tls13_downgrade_11[8];
417 extern const uint8_t tls13_hello_retry_request_hash[32];
418 extern const uint8_t tls13_cert_verify_pad[64];
419 extern const uint8_t tls13_cert_client_verify_context[];
420 extern const uint8_t tls13_cert_server_verify_context[];
421 
422 __END_HIDDEN_DECLS
423 
424 #endif
425