1 /* $OpenBSD: tls13_internal.h,v 1.98 2022/07/17 15:49:20 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, CBS *_cbs); 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 int tls13_handshake_msg_set_buffer(struct tls13_handshake_msg *msg, CBS *cbs); 230 uint8_t tls13_handshake_msg_type(struct tls13_handshake_msg *msg); 231 int tls13_handshake_msg_content(struct tls13_handshake_msg *msg, CBS *cbs); 232 int tls13_handshake_msg_start(struct tls13_handshake_msg *msg, CBB *body, 233 uint8_t msg_type); 234 int tls13_handshake_msg_finish(struct tls13_handshake_msg *msg); 235 int tls13_handshake_msg_recv(struct tls13_handshake_msg *msg, 236 struct tls13_record_layer *rl); 237 int tls13_handshake_msg_send(struct tls13_handshake_msg *msg, 238 struct tls13_record_layer *rl); 239 240 struct tls13_handshake_stage { 241 uint8_t hs_type; 242 uint8_t message_number; 243 }; 244 245 struct ssl_handshake_tls13_st; 246 247 struct tls13_error { 248 int code; 249 int subcode; 250 int errnum; 251 const char *file; 252 int line; 253 char *msg; 254 }; 255 256 struct tls13_ctx { 257 struct tls13_error error; 258 259 SSL *ssl; 260 struct ssl_handshake_st *hs; 261 uint8_t mode; 262 struct tls13_handshake_stage handshake_stage; 263 int handshake_started; 264 int handshake_completed; 265 int need_flush; 266 int middlebox_compat; 267 int send_dummy_ccs; 268 int send_dummy_ccs_after; 269 270 int close_notify_sent; 271 int close_notify_recv; 272 273 const EVP_AEAD *aead; 274 const EVP_MD *hash; 275 276 struct tls13_record_layer *rl; 277 struct tls13_handshake_msg *hs_msg; 278 uint8_t key_update_request; 279 uint8_t alert; 280 int phh_count; 281 time_t phh_last_seen; 282 283 tls13_handshake_message_cb handshake_message_sent_cb; 284 tls13_handshake_message_cb handshake_message_recv_cb; 285 tls13_info_cb info_cb; 286 tls13_ocsp_status_cb ocsp_status_recv_cb; 287 }; 288 #ifndef TLS13_PHH_LIMIT_TIME 289 #define TLS13_PHH_LIMIT_TIME 3600 290 #endif 291 #ifndef TLS13_PHH_LIMIT 292 #define TLS13_PHH_LIMIT 100 293 #endif 294 295 struct tls13_ctx *tls13_ctx_new(int mode, SSL *ssl); 296 void tls13_ctx_free(struct tls13_ctx *ctx); 297 298 const EVP_AEAD *tls13_cipher_aead(const SSL_CIPHER *cipher); 299 const EVP_MD *tls13_cipher_hash(const SSL_CIPHER *cipher); 300 301 /* 302 * Legacy interfaces. 303 */ 304 int tls13_use_legacy_client(struct tls13_ctx *ctx); 305 int tls13_use_legacy_server(struct tls13_ctx *ctx); 306 int tls13_legacy_accept(SSL *ssl); 307 int tls13_legacy_connect(SSL *ssl); 308 int tls13_legacy_return_code(SSL *ssl, ssize_t ret); 309 ssize_t tls13_legacy_wire_read_cb(void *buf, size_t n, void *arg); 310 ssize_t tls13_legacy_wire_write_cb(const void *buf, size_t n, void *arg); 311 ssize_t tls13_legacy_wire_flush_cb(void *arg); 312 int tls13_legacy_pending(const SSL *ssl); 313 int tls13_legacy_read_bytes(SSL *ssl, int type, unsigned char *buf, int len, 314 int peek); 315 int tls13_legacy_write_bytes(SSL *ssl, int type, const void *buf, int len); 316 int tls13_legacy_shutdown(SSL *ssl); 317 int tls13_legacy_servername_process(struct tls13_ctx *ctx, uint8_t *alert); 318 319 /* 320 * Message Types - RFC 8446, Section B.3. 321 * 322 * Values listed as "_RESERVED" were used in previous versions of TLS and are 323 * listed here for completeness. TLS 1.3 implementations MUST NOT send them but 324 * might receive them from older TLS implementations. 325 */ 326 #define TLS13_MT_HELLO_REQUEST_RESERVED 0 327 #define TLS13_MT_CLIENT_HELLO 1 328 #define TLS13_MT_SERVER_HELLO 2 329 #define TLS13_MT_HELLO_VERIFY_REQUEST_RESERVED 3 330 #define TLS13_MT_NEW_SESSION_TICKET 4 331 #define TLS13_MT_END_OF_EARLY_DATA 5 332 #define TLS13_MT_HELLO_RETRY_REQUEST_RESERVED 6 333 #define TLS13_MT_ENCRYPTED_EXTENSIONS 8 334 #define TLS13_MT_CERTIFICATE 11 335 #define TLS13_MT_SERVER_KEY_EXCHANGE_RESERVED 12 336 #define TLS13_MT_CERTIFICATE_REQUEST 13 337 #define TLS13_MT_SERVER_HELLO_DONE_RESERVED 14 338 #define TLS13_MT_CERTIFICATE_VERIFY 15 339 #define TLS13_MT_CLIENT_KEY_EXCHANGE_RESERVED 16 340 #define TLS13_MT_FINISHED 20 341 #define TLS13_MT_CERTIFICATE_URL_RESERVED 21 342 #define TLS13_MT_CERTIFICATE_STATUS_RESERVED 22 343 #define TLS13_MT_SUPPLEMENTAL_DATA_RESERVED 23 344 #define TLS13_MT_KEY_UPDATE 24 345 #define TLS13_MT_MESSAGE_HASH 254 346 347 int tls13_handshake_msg_record(struct tls13_ctx *ctx); 348 int tls13_handshake_perform(struct tls13_ctx *ctx); 349 350 int tls13_client_init(struct tls13_ctx *ctx); 351 int tls13_server_init(struct tls13_ctx *ctx); 352 int tls13_client_connect(struct tls13_ctx *ctx); 353 int tls13_server_accept(struct tls13_ctx *ctx); 354 355 int tls13_client_hello_send(struct tls13_ctx *ctx, CBB *cbb); 356 int tls13_client_hello_sent(struct tls13_ctx *ctx); 357 int tls13_client_hello_recv(struct tls13_ctx *ctx, CBS *cbs); 358 int tls13_client_hello_retry_send(struct tls13_ctx *ctx, CBB *cbb); 359 int tls13_client_hello_retry_recv(struct tls13_ctx *ctx, CBS *cbs); 360 int tls13_client_end_of_early_data_send(struct tls13_ctx *ctx, CBB *cbb); 361 int tls13_client_end_of_early_data_recv(struct tls13_ctx *ctx, CBS *cbs); 362 int tls13_client_certificate_send(struct tls13_ctx *ctx, CBB *cbb); 363 int tls13_client_certificate_recv(struct tls13_ctx *ctx, CBS *cbs); 364 int tls13_client_certificate_verify_send(struct tls13_ctx *ctx, CBB *cbb); 365 int tls13_client_certificate_verify_recv(struct tls13_ctx *ctx, CBS *cbs); 366 int tls13_client_finished_recv(struct tls13_ctx *ctx, CBS *cbs); 367 int tls13_client_finished_send(struct tls13_ctx *ctx, CBB *cbb); 368 int tls13_client_finished_sent(struct tls13_ctx *ctx); 369 int tls13_server_hello_recv(struct tls13_ctx *ctx, CBS *cbs); 370 int tls13_server_hello_send(struct tls13_ctx *ctx, CBB *cbb); 371 int tls13_server_hello_sent(struct tls13_ctx *ctx); 372 int tls13_server_hello_retry_request_recv(struct tls13_ctx *ctx, CBS *cbs); 373 int tls13_server_hello_retry_request_send(struct tls13_ctx *ctx, CBB *cbb); 374 int tls13_server_hello_retry_request_sent(struct tls13_ctx *ctx); 375 int tls13_server_encrypted_extensions_recv(struct tls13_ctx *ctx, CBS *cbs); 376 int tls13_server_encrypted_extensions_send(struct tls13_ctx *ctx, CBB *cbb); 377 int tls13_server_certificate_recv(struct tls13_ctx *ctx, CBS *cbs); 378 int tls13_server_certificate_send(struct tls13_ctx *ctx, CBB *cbb); 379 int tls13_server_certificate_request_recv(struct tls13_ctx *ctx, CBS *cbs); 380 int tls13_server_certificate_request_send(struct tls13_ctx *ctx, CBB *cbb); 381 int tls13_server_certificate_verify_send(struct tls13_ctx *ctx, CBB *cbb); 382 int tls13_server_certificate_verify_recv(struct tls13_ctx *ctx, CBS *cbs); 383 int tls13_server_finished_recv(struct tls13_ctx *ctx, CBS *cbs); 384 int tls13_server_finished_send(struct tls13_ctx *ctx, CBB *cbb); 385 int tls13_server_finished_sent(struct tls13_ctx *ctx); 386 387 void tls13_error_clear(struct tls13_error *error); 388 int tls13_cert_add(struct tls13_ctx *ctx, CBB *cbb, X509 *cert, 389 int(*build_extensions)(SSL *s, uint16_t msg_type, CBB *cbb)); 390 391 int tls13_synthetic_handshake_message(struct tls13_ctx *ctx); 392 int tls13_clienthello_hash_init(struct tls13_ctx *ctx); 393 void tls13_clienthello_hash_clear(struct ssl_handshake_tls13_st *hs); 394 int tls13_clienthello_hash_update_bytes(struct tls13_ctx *ctx, void *data, 395 size_t len); 396 int tls13_clienthello_hash_update(struct tls13_ctx *ctx, CBS *cbs); 397 int tls13_clienthello_hash_finalize(struct tls13_ctx *ctx); 398 int tls13_clienthello_hash_validate(struct tls13_ctx *ctx); 399 400 int tls13_error_set(struct tls13_error *error, int code, int subcode, 401 const char *file, int line, const char *fmt, ...); 402 int tls13_error_setx(struct tls13_error *error, int code, int subcode, 403 const char *file, int line, const char *fmt, ...); 404 405 #define tls13_set_error(ctx, code, subcode, fmt, ...) \ 406 tls13_error_set(&(ctx)->error, (code), (subcode), __FILE__, __LINE__, \ 407 (fmt), __VA_ARGS__) 408 #define tls13_set_errorx(ctx, code, subcode, fmt, ...) \ 409 tls13_error_setx(&(ctx)->error, (code), (subcode), __FILE__, __LINE__, \ 410 (fmt), __VA_ARGS__) 411 412 int tls13_exporter(struct tls13_ctx *ctx, const uint8_t *label, size_t label_len, 413 const uint8_t *context_value, size_t context_value_len, uint8_t *out, 414 size_t out_len); 415 416 extern const uint8_t tls13_downgrade_12[8]; 417 extern const uint8_t tls13_downgrade_11[8]; 418 extern const uint8_t tls13_hello_retry_request_hash[32]; 419 extern const uint8_t tls13_cert_verify_pad[64]; 420 extern const uint8_t tls13_cert_client_verify_context[]; 421 extern const uint8_t tls13_cert_server_verify_context[]; 422 423 __END_HIDDEN_DECLS 424 425 #endif 426