diff options
Diffstat (limited to 'src/lib/libssl/tls13_lib.c')
| -rw-r--r-- | src/lib/libssl/tls13_lib.c | 650 |
1 files changed, 0 insertions, 650 deletions
diff --git a/src/lib/libssl/tls13_lib.c b/src/lib/libssl/tls13_lib.c deleted file mode 100644 index f064521c8b..0000000000 --- a/src/lib/libssl/tls13_lib.c +++ /dev/null | |||
| @@ -1,650 +0,0 @@ | |||
| 1 | /* $OpenBSD: tls13_lib.c,v 1.59 2021/04/07 21:48:23 tb Exp $ */ | ||
| 2 | /* | ||
| 3 | * Copyright (c) 2018, 2019 Joel Sing <jsing@openbsd.org> | ||
| 4 | * Copyright (c) 2019 Bob Beck <beck@openbsd.org> | ||
| 5 | * | ||
| 6 | * Permission to use, copy, modify, and distribute this software for any | ||
| 7 | * purpose with or without fee is hereby granted, provided that the above | ||
| 8 | * copyright notice and this permission notice appear in all copies. | ||
| 9 | * | ||
| 10 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES | ||
| 11 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF | ||
| 12 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR | ||
| 13 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES | ||
| 14 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN | ||
| 15 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF | ||
| 16 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. | ||
| 17 | */ | ||
| 18 | |||
| 19 | #include <stddef.h> | ||
| 20 | |||
| 21 | #include <openssl/evp.h> | ||
| 22 | |||
| 23 | #include "ssl_locl.h" | ||
| 24 | #include "ssl_tlsext.h" | ||
| 25 | #include "tls13_internal.h" | ||
| 26 | |||
| 27 | /* | ||
| 28 | * Downgrade sentinels - RFC 8446 section 4.1.3, magic values which must be set | ||
| 29 | * by the server in server random if it is willing to downgrade but supports | ||
| 30 | * TLSv1.3 | ||
| 31 | */ | ||
| 32 | const uint8_t tls13_downgrade_12[8] = { | ||
| 33 | 0x44, 0x4f, 0x57, 0x4e, 0x47, 0x52, 0x44, 0x01, | ||
| 34 | }; | ||
| 35 | const uint8_t tls13_downgrade_11[8] = { | ||
| 36 | 0x44, 0x4f, 0x57, 0x4e, 0x47, 0x52, 0x44, 0x00, | ||
| 37 | }; | ||
| 38 | |||
| 39 | /* | ||
| 40 | * HelloRetryRequest hash - RFC 8446 section 4.1.3. | ||
| 41 | */ | ||
| 42 | const uint8_t tls13_hello_retry_request_hash[32] = { | ||
| 43 | 0xcf, 0x21, 0xad, 0x74, 0xe5, 0x9a, 0x61, 0x11, | ||
| 44 | 0xbe, 0x1d, 0x8c, 0x02, 0x1e, 0x65, 0xb8, 0x91, | ||
| 45 | 0xc2, 0xa2, 0x11, 0x16, 0x7a, 0xbb, 0x8c, 0x5e, | ||
| 46 | 0x07, 0x9e, 0x09, 0xe2, 0xc8, 0xa8, 0x33, 0x9c, | ||
| 47 | }; | ||
| 48 | |||
| 49 | /* | ||
| 50 | * Certificate Verify padding - RFC 8446 section 4.4.3. | ||
| 51 | */ | ||
| 52 | const uint8_t tls13_cert_verify_pad[64] = { | ||
| 53 | 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, | ||
| 54 | 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, | ||
| 55 | 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, | ||
| 56 | 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, | ||
| 57 | 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, | ||
| 58 | 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, | ||
| 59 | 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, | ||
| 60 | 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, | ||
| 61 | }; | ||
| 62 | |||
| 63 | const uint8_t tls13_cert_client_verify_context[] = | ||
| 64 | "TLS 1.3, client CertificateVerify"; | ||
| 65 | const uint8_t tls13_cert_server_verify_context[] = | ||
| 66 | "TLS 1.3, server CertificateVerify"; | ||
| 67 | |||
| 68 | const EVP_AEAD * | ||
| 69 | tls13_cipher_aead(const SSL_CIPHER *cipher) | ||
| 70 | { | ||
| 71 | if (cipher == NULL) | ||
| 72 | return NULL; | ||
| 73 | if (cipher->algorithm_ssl != SSL_TLSV1_3) | ||
| 74 | return NULL; | ||
| 75 | |||
| 76 | switch (cipher->algorithm_enc) { | ||
| 77 | case SSL_AES128GCM: | ||
| 78 | return EVP_aead_aes_128_gcm(); | ||
| 79 | case SSL_AES256GCM: | ||
| 80 | return EVP_aead_aes_256_gcm(); | ||
| 81 | case SSL_CHACHA20POLY1305: | ||
| 82 | return EVP_aead_chacha20_poly1305(); | ||
| 83 | } | ||
| 84 | |||
| 85 | return NULL; | ||
| 86 | } | ||
| 87 | |||
| 88 | const EVP_MD * | ||
| 89 | tls13_cipher_hash(const SSL_CIPHER *cipher) | ||
| 90 | { | ||
| 91 | if (cipher == NULL) | ||
| 92 | return NULL; | ||
| 93 | if (cipher->algorithm_ssl != SSL_TLSV1_3) | ||
| 94 | return NULL; | ||
| 95 | |||
| 96 | switch (cipher->algorithm2) { | ||
| 97 | case SSL_HANDSHAKE_MAC_SHA256: | ||
| 98 | return EVP_sha256(); | ||
| 99 | case SSL_HANDSHAKE_MAC_SHA384: | ||
| 100 | return EVP_sha384(); | ||
| 101 | } | ||
| 102 | |||
| 103 | return NULL; | ||
| 104 | } | ||
| 105 | |||
| 106 | static void | ||
| 107 | tls13_alert_received_cb(uint8_t alert_desc, void *arg) | ||
| 108 | { | ||
| 109 | struct tls13_ctx *ctx = arg; | ||
| 110 | |||
| 111 | if (alert_desc == TLS13_ALERT_CLOSE_NOTIFY) { | ||
| 112 | ctx->close_notify_recv = 1; | ||
| 113 | ctx->ssl->internal->shutdown |= SSL_RECEIVED_SHUTDOWN; | ||
| 114 | S3I(ctx->ssl)->warn_alert = alert_desc; | ||
| 115 | return; | ||
| 116 | } | ||
| 117 | |||
| 118 | if (alert_desc == TLS13_ALERT_USER_CANCELED) { | ||
| 119 | /* | ||
| 120 | * We treat this as advisory, since a close_notify alert | ||
| 121 | * SHOULD follow this alert (RFC 8446 section 6.1). | ||
| 122 | */ | ||
| 123 | return; | ||
| 124 | } | ||
| 125 | |||
| 126 | /* All other alerts are treated as fatal in TLSv1.3. */ | ||
| 127 | S3I(ctx->ssl)->fatal_alert = alert_desc; | ||
| 128 | |||
| 129 | SSLerror(ctx->ssl, SSL_AD_REASON_OFFSET + alert_desc); | ||
| 130 | ERR_asprintf_error_data("SSL alert number %d", alert_desc); | ||
| 131 | |||
| 132 | SSL_CTX_remove_session(ctx->ssl->ctx, ctx->ssl->session); | ||
| 133 | } | ||
| 134 | |||
| 135 | static void | ||
| 136 | tls13_alert_sent_cb(uint8_t alert_desc, void *arg) | ||
| 137 | { | ||
| 138 | struct tls13_ctx *ctx = arg; | ||
| 139 | |||
| 140 | if (alert_desc == TLS13_ALERT_CLOSE_NOTIFY) { | ||
| 141 | ctx->close_notify_sent = 1; | ||
| 142 | return; | ||
| 143 | } | ||
| 144 | |||
| 145 | if (alert_desc == TLS13_ALERT_USER_CANCELED) { | ||
| 146 | return; | ||
| 147 | } | ||
| 148 | |||
| 149 | /* All other alerts are treated as fatal in TLSv1.3. */ | ||
| 150 | if (ctx->error.code == 0) | ||
| 151 | SSLerror(ctx->ssl, SSL_AD_REASON_OFFSET + alert_desc); | ||
| 152 | } | ||
| 153 | |||
| 154 | static void | ||
| 155 | tls13_legacy_handshake_message_recv_cb(void *arg) | ||
| 156 | { | ||
| 157 | struct tls13_ctx *ctx = arg; | ||
| 158 | SSL *s = ctx->ssl; | ||
| 159 | CBS cbs; | ||
| 160 | |||
| 161 | if (s->internal->msg_callback == NULL) | ||
| 162 | return; | ||
| 163 | |||
| 164 | tls13_handshake_msg_data(ctx->hs_msg, &cbs); | ||
| 165 | s->internal->msg_callback(0, TLS1_3_VERSION, SSL3_RT_HANDSHAKE, | ||
| 166 | CBS_data(&cbs), CBS_len(&cbs), s, s->internal->msg_callback_arg); | ||
| 167 | } | ||
| 168 | |||
| 169 | static void | ||
| 170 | tls13_legacy_handshake_message_sent_cb(void *arg) | ||
| 171 | { | ||
| 172 | struct tls13_ctx *ctx = arg; | ||
| 173 | SSL *s = ctx->ssl; | ||
| 174 | CBS cbs; | ||
| 175 | |||
| 176 | if (s->internal->msg_callback == NULL) | ||
| 177 | return; | ||
| 178 | |||
| 179 | tls13_handshake_msg_data(ctx->hs_msg, &cbs); | ||
| 180 | s->internal->msg_callback(1, TLS1_3_VERSION, SSL3_RT_HANDSHAKE, | ||
| 181 | CBS_data(&cbs), CBS_len(&cbs), s, s->internal->msg_callback_arg); | ||
| 182 | } | ||
| 183 | |||
| 184 | static void | ||
| 185 | tls13_legacy_info_cb(void *arg, int state, int ret) | ||
| 186 | { | ||
| 187 | struct tls13_ctx *ctx = arg; | ||
| 188 | SSL *s = ctx->ssl; | ||
| 189 | void (*cb)(const SSL *, int, int); | ||
| 190 | |||
| 191 | if ((cb = s->internal->info_callback) == NULL) | ||
| 192 | cb = s->ctx->internal->info_callback; | ||
| 193 | if (cb != NULL) | ||
| 194 | cb(s, state, ret); | ||
| 195 | } | ||
| 196 | |||
| 197 | static int | ||
| 198 | tls13_legacy_ocsp_status_recv_cb(void *arg) | ||
| 199 | { | ||
| 200 | struct tls13_ctx *ctx = arg; | ||
| 201 | SSL *s = ctx->ssl; | ||
| 202 | int ret; | ||
| 203 | |||
| 204 | if (s->ctx->internal->tlsext_status_cb == NULL || | ||
| 205 | s->internal->tlsext_ocsp_resp == NULL) | ||
| 206 | return 1; | ||
| 207 | |||
| 208 | ret = s->ctx->internal->tlsext_status_cb(s, | ||
| 209 | s->ctx->internal->tlsext_status_arg); | ||
| 210 | if (ret < 0) { | ||
| 211 | ctx->alert = TLS13_ALERT_INTERNAL_ERROR; | ||
| 212 | SSLerror(s, ERR_R_MALLOC_FAILURE); | ||
| 213 | return 0; | ||
| 214 | } | ||
| 215 | if (ret == 0) { | ||
| 216 | ctx->alert = TLS13_ALERT_BAD_CERTIFICATE_STATUS_RESPONSE; | ||
| 217 | SSLerror(s, SSL_R_INVALID_STATUS_RESPONSE); | ||
| 218 | return 0; | ||
| 219 | } | ||
| 220 | |||
| 221 | return 1; | ||
| 222 | } | ||
| 223 | |||
| 224 | static int | ||
| 225 | tls13_phh_update_local_traffic_secret(struct tls13_ctx *ctx) | ||
| 226 | { | ||
| 227 | struct tls13_secrets *secrets = ctx->hs->tls13.secrets; | ||
| 228 | |||
| 229 | if (ctx->mode == TLS13_HS_CLIENT) | ||
| 230 | return (tls13_update_client_traffic_secret(secrets) && | ||
| 231 | tls13_record_layer_set_write_traffic_key(ctx->rl, | ||
| 232 | &secrets->client_application_traffic)); | ||
| 233 | return (tls13_update_server_traffic_secret(secrets) && | ||
| 234 | tls13_record_layer_set_read_traffic_key(ctx->rl, | ||
| 235 | &secrets->server_application_traffic)); | ||
| 236 | } | ||
| 237 | |||
| 238 | static int | ||
| 239 | tls13_phh_update_peer_traffic_secret(struct tls13_ctx *ctx) | ||
| 240 | { | ||
| 241 | struct tls13_secrets *secrets = ctx->hs->tls13.secrets; | ||
| 242 | |||
| 243 | if (ctx->mode == TLS13_HS_CLIENT) | ||
| 244 | return (tls13_update_server_traffic_secret(secrets) && | ||
| 245 | tls13_record_layer_set_read_traffic_key(ctx->rl, | ||
| 246 | &secrets->server_application_traffic)); | ||
| 247 | return (tls13_update_client_traffic_secret(secrets) && | ||
| 248 | tls13_record_layer_set_write_traffic_key(ctx->rl, | ||
| 249 | &secrets->client_application_traffic)); | ||
| 250 | } | ||
| 251 | |||
| 252 | /* | ||
| 253 | * XXX arbitrarily chosen limit of 100 post handshake handshake | ||
| 254 | * messages in an hour - to avoid a hostile peer from constantly | ||
| 255 | * requesting certificates or key renegotiaitons, etc. | ||
| 256 | */ | ||
| 257 | static int | ||
| 258 | tls13_phh_limit_check(struct tls13_ctx *ctx) | ||
| 259 | { | ||
| 260 | time_t now = time(NULL); | ||
| 261 | |||
| 262 | if (ctx->phh_last_seen > now - TLS13_PHH_LIMIT_TIME) { | ||
| 263 | if (ctx->phh_count > TLS13_PHH_LIMIT) | ||
| 264 | return 0; | ||
| 265 | } else | ||
| 266 | ctx->phh_count = 0; | ||
| 267 | ctx->phh_count++; | ||
| 268 | ctx->phh_last_seen = now; | ||
| 269 | return 1; | ||
| 270 | } | ||
| 271 | |||
| 272 | static ssize_t | ||
| 273 | tls13_key_update_recv(struct tls13_ctx *ctx, CBS *cbs) | ||
| 274 | { | ||
| 275 | struct tls13_handshake_msg *hs_msg = NULL; | ||
| 276 | CBB cbb_hs; | ||
| 277 | CBS cbs_hs; | ||
| 278 | uint8_t alert = TLS13_ALERT_INTERNAL_ERROR; | ||
| 279 | uint8_t key_update_request; | ||
| 280 | ssize_t ret; | ||
| 281 | |||
| 282 | if (!CBS_get_u8(cbs, &key_update_request)) { | ||
| 283 | alert = TLS13_ALERT_DECODE_ERROR; | ||
| 284 | goto err; | ||
| 285 | } | ||
| 286 | if (CBS_len(cbs) != 0) { | ||
| 287 | alert = TLS13_ALERT_DECODE_ERROR; | ||
| 288 | goto err; | ||
| 289 | } | ||
| 290 | if (key_update_request > 1) { | ||
| 291 | alert = TLS13_ALERT_ILLEGAL_PARAMETER; | ||
| 292 | goto err; | ||
| 293 | } | ||
| 294 | |||
| 295 | if (!tls13_phh_update_peer_traffic_secret(ctx)) | ||
| 296 | goto err; | ||
| 297 | |||
| 298 | if (key_update_request == 0) | ||
| 299 | return TLS13_IO_SUCCESS; | ||
| 300 | |||
| 301 | /* key_update_request == 1 */ | ||
| 302 | if ((hs_msg = tls13_handshake_msg_new()) == NULL) | ||
| 303 | goto err; | ||
| 304 | if (!tls13_handshake_msg_start(hs_msg, &cbb_hs, TLS13_MT_KEY_UPDATE)) | ||
| 305 | goto err; | ||
| 306 | if (!CBB_add_u8(&cbb_hs, 0)) | ||
| 307 | goto err; | ||
| 308 | if (!tls13_handshake_msg_finish(hs_msg)) | ||
| 309 | goto err; | ||
| 310 | |||
| 311 | ctx->key_update_request = 1; | ||
| 312 | tls13_handshake_msg_data(hs_msg, &cbs_hs); | ||
| 313 | ret = tls13_record_layer_phh(ctx->rl, &cbs_hs); | ||
| 314 | |||
| 315 | tls13_handshake_msg_free(hs_msg); | ||
| 316 | hs_msg = NULL; | ||
| 317 | |||
| 318 | return ret; | ||
| 319 | |||
| 320 | err: | ||
| 321 | tls13_handshake_msg_free(hs_msg); | ||
| 322 | |||
| 323 | return tls13_send_alert(ctx->rl, alert); | ||
| 324 | } | ||
| 325 | |||
| 326 | static void | ||
| 327 | tls13_phh_done_cb(void *cb_arg) | ||
| 328 | { | ||
| 329 | struct tls13_ctx *ctx = cb_arg; | ||
| 330 | |||
| 331 | if (ctx->key_update_request) { | ||
| 332 | tls13_phh_update_local_traffic_secret(ctx); | ||
| 333 | ctx->key_update_request = 0; | ||
| 334 | } | ||
| 335 | } | ||
| 336 | |||
| 337 | static ssize_t | ||
| 338 | tls13_phh_received_cb(void *cb_arg, CBS *cbs) | ||
| 339 | { | ||
| 340 | ssize_t ret = TLS13_IO_FAILURE; | ||
| 341 | struct tls13_ctx *ctx = cb_arg; | ||
| 342 | CBS phh_cbs; | ||
| 343 | |||
| 344 | if (!tls13_phh_limit_check(ctx)) | ||
| 345 | return tls13_send_alert(ctx->rl, TLS13_ALERT_UNEXPECTED_MESSAGE); | ||
| 346 | |||
| 347 | if ((ctx->hs_msg == NULL) && | ||
| 348 | ((ctx->hs_msg = tls13_handshake_msg_new()) == NULL)) | ||
| 349 | return TLS13_IO_FAILURE; | ||
| 350 | |||
| 351 | if (!tls13_handshake_msg_set_buffer(ctx->hs_msg, cbs)) | ||
| 352 | return TLS13_IO_FAILURE; | ||
| 353 | |||
| 354 | if ((ret = tls13_handshake_msg_recv(ctx->hs_msg, ctx->rl)) | ||
| 355 | != TLS13_IO_SUCCESS) | ||
| 356 | return ret; | ||
| 357 | |||
| 358 | if (!tls13_handshake_msg_content(ctx->hs_msg, &phh_cbs)) | ||
| 359 | return TLS13_IO_FAILURE; | ||
| 360 | |||
| 361 | switch(tls13_handshake_msg_type(ctx->hs_msg)) { | ||
| 362 | case TLS13_MT_KEY_UPDATE: | ||
| 363 | ret = tls13_key_update_recv(ctx, &phh_cbs); | ||
| 364 | break; | ||
| 365 | case TLS13_MT_NEW_SESSION_TICKET: | ||
| 366 | /* XXX do nothing for now and ignore this */ | ||
| 367 | break; | ||
| 368 | case TLS13_MT_CERTIFICATE_REQUEST: | ||
| 369 | /* XXX add support if we choose to advertise this */ | ||
| 370 | /* FALLTHROUGH */ | ||
| 371 | default: | ||
| 372 | ret = TLS13_IO_FAILURE; /* XXX send alert */ | ||
| 373 | break; | ||
| 374 | } | ||
| 375 | |||
| 376 | tls13_handshake_msg_free(ctx->hs_msg); | ||
| 377 | ctx->hs_msg = NULL; | ||
| 378 | return ret; | ||
| 379 | } | ||
| 380 | |||
| 381 | static const struct tls13_record_layer_callbacks rl_callbacks = { | ||
| 382 | .wire_read = tls13_legacy_wire_read_cb, | ||
| 383 | .wire_write = tls13_legacy_wire_write_cb, | ||
| 384 | .alert_recv = tls13_alert_received_cb, | ||
| 385 | .alert_sent = tls13_alert_sent_cb, | ||
| 386 | .phh_recv = tls13_phh_received_cb, | ||
| 387 | .phh_sent = tls13_phh_done_cb, | ||
| 388 | }; | ||
| 389 | |||
| 390 | struct tls13_ctx * | ||
| 391 | tls13_ctx_new(int mode) | ||
| 392 | { | ||
| 393 | struct tls13_ctx *ctx = NULL; | ||
| 394 | |||
| 395 | if ((ctx = calloc(sizeof(struct tls13_ctx), 1)) == NULL) | ||
| 396 | goto err; | ||
| 397 | |||
| 398 | ctx->mode = mode; | ||
| 399 | |||
| 400 | if ((ctx->rl = tls13_record_layer_new(&rl_callbacks, ctx)) == NULL) | ||
| 401 | goto err; | ||
| 402 | |||
| 403 | ctx->handshake_message_sent_cb = tls13_legacy_handshake_message_sent_cb; | ||
| 404 | ctx->handshake_message_recv_cb = tls13_legacy_handshake_message_recv_cb; | ||
| 405 | ctx->info_cb = tls13_legacy_info_cb; | ||
| 406 | ctx->ocsp_status_recv_cb = tls13_legacy_ocsp_status_recv_cb; | ||
| 407 | |||
| 408 | ctx->middlebox_compat = 1; | ||
| 409 | |||
| 410 | return ctx; | ||
| 411 | |||
| 412 | err: | ||
| 413 | tls13_ctx_free(ctx); | ||
| 414 | |||
| 415 | return NULL; | ||
| 416 | } | ||
| 417 | |||
| 418 | void | ||
| 419 | tls13_ctx_free(struct tls13_ctx *ctx) | ||
| 420 | { | ||
| 421 | if (ctx == NULL) | ||
| 422 | return; | ||
| 423 | |||
| 424 | tls13_error_clear(&ctx->error); | ||
| 425 | tls13_record_layer_free(ctx->rl); | ||
| 426 | tls13_handshake_msg_free(ctx->hs_msg); | ||
| 427 | |||
| 428 | freezero(ctx, sizeof(struct tls13_ctx)); | ||
| 429 | } | ||
| 430 | |||
| 431 | int | ||
| 432 | tls13_cert_add(struct tls13_ctx *ctx, CBB *cbb, X509 *cert, | ||
| 433 | int (*build_extensions)(SSL *s, uint16_t msg_type, CBB *cbb)) | ||
| 434 | { | ||
| 435 | CBB cert_data, cert_exts; | ||
| 436 | uint8_t *data; | ||
| 437 | int cert_len; | ||
| 438 | |||
| 439 | if ((cert_len = i2d_X509(cert, NULL)) < 0) | ||
| 440 | return 0; | ||
| 441 | |||
| 442 | if (!CBB_add_u24_length_prefixed(cbb, &cert_data)) | ||
| 443 | return 0; | ||
| 444 | if (!CBB_add_space(&cert_data, &data, cert_len)) | ||
| 445 | return 0; | ||
| 446 | if (i2d_X509(cert, &data) != cert_len) | ||
| 447 | return 0; | ||
| 448 | if (build_extensions != NULL) { | ||
| 449 | if (!build_extensions(ctx->ssl, SSL_TLSEXT_MSG_CT, cbb)) | ||
| 450 | return 0; | ||
| 451 | } else { | ||
| 452 | if (!CBB_add_u16_length_prefixed(cbb, &cert_exts)) | ||
| 453 | return 0; | ||
| 454 | } | ||
| 455 | if (!CBB_flush(cbb)) | ||
| 456 | return 0; | ||
| 457 | |||
| 458 | return 1; | ||
| 459 | } | ||
| 460 | |||
| 461 | int | ||
| 462 | tls13_synthetic_handshake_message(struct tls13_ctx *ctx) | ||
| 463 | { | ||
| 464 | struct tls13_handshake_msg *hm = NULL; | ||
| 465 | unsigned char buf[EVP_MAX_MD_SIZE]; | ||
| 466 | size_t hash_len; | ||
| 467 | CBB cbb; | ||
| 468 | CBS cbs; | ||
| 469 | SSL *s = ctx->ssl; | ||
| 470 | int ret = 0; | ||
| 471 | |||
| 472 | /* | ||
| 473 | * Replace ClientHello with synthetic handshake message - see | ||
| 474 | * RFC 8446 section 4.4.1. | ||
| 475 | */ | ||
| 476 | if (!tls1_transcript_hash_init(s)) | ||
| 477 | goto err; | ||
| 478 | if (!tls1_transcript_hash_value(s, buf, sizeof(buf), &hash_len)) | ||
| 479 | goto err; | ||
| 480 | |||
| 481 | if ((hm = tls13_handshake_msg_new()) == NULL) | ||
| 482 | goto err; | ||
| 483 | if (!tls13_handshake_msg_start(hm, &cbb, TLS13_MT_MESSAGE_HASH)) | ||
| 484 | goto err; | ||
| 485 | if (!CBB_add_bytes(&cbb, buf, hash_len)) | ||
| 486 | goto err; | ||
| 487 | if (!tls13_handshake_msg_finish(hm)) | ||
| 488 | goto err; | ||
| 489 | |||
| 490 | tls13_handshake_msg_data(hm, &cbs); | ||
| 491 | |||
| 492 | tls1_transcript_reset(ctx->ssl); | ||
| 493 | if (!tls1_transcript_record(ctx->ssl, CBS_data(&cbs), CBS_len(&cbs))) | ||
| 494 | goto err; | ||
| 495 | |||
| 496 | ret = 1; | ||
| 497 | |||
| 498 | err: | ||
| 499 | tls13_handshake_msg_free(hm); | ||
| 500 | |||
| 501 | return ret; | ||
| 502 | } | ||
| 503 | |||
| 504 | int | ||
| 505 | tls13_clienthello_hash_init(struct tls13_ctx *ctx) | ||
| 506 | { | ||
| 507 | if (ctx->hs->tls13.clienthello_md_ctx != NULL) | ||
| 508 | return 0; | ||
| 509 | if ((ctx->hs->tls13.clienthello_md_ctx = EVP_MD_CTX_new()) == NULL) | ||
| 510 | return 0; | ||
| 511 | if (!EVP_DigestInit_ex(ctx->hs->tls13.clienthello_md_ctx, | ||
| 512 | EVP_sha256(), NULL)) | ||
| 513 | return 0; | ||
| 514 | |||
| 515 | if ((ctx->hs->tls13.clienthello_hash == NULL) && | ||
| 516 | (ctx->hs->tls13.clienthello_hash = calloc(1, EVP_MAX_MD_SIZE)) == | ||
| 517 | NULL) | ||
| 518 | return 0; | ||
| 519 | |||
| 520 | return 1; | ||
| 521 | } | ||
| 522 | |||
| 523 | void | ||
| 524 | tls13_clienthello_hash_clear(struct ssl_handshake_tls13_st *hs) /* XXX */ | ||
| 525 | { | ||
| 526 | EVP_MD_CTX_free(hs->clienthello_md_ctx); | ||
| 527 | hs->clienthello_md_ctx = NULL; | ||
| 528 | freezero(hs->clienthello_hash, EVP_MAX_MD_SIZE); | ||
| 529 | hs->clienthello_hash = NULL; | ||
| 530 | } | ||
| 531 | |||
| 532 | int | ||
| 533 | tls13_clienthello_hash_update_bytes(struct tls13_ctx *ctx, void *data, | ||
| 534 | size_t len) | ||
| 535 | { | ||
| 536 | return EVP_DigestUpdate(ctx->hs->tls13.clienthello_md_ctx, data, len); | ||
| 537 | } | ||
| 538 | |||
| 539 | int | ||
| 540 | tls13_clienthello_hash_update(struct tls13_ctx *ctx, CBS *cbs) | ||
| 541 | { | ||
| 542 | return tls13_clienthello_hash_update_bytes(ctx, (void *)CBS_data(cbs), | ||
| 543 | CBS_len(cbs)); | ||
| 544 | } | ||
| 545 | |||
| 546 | int | ||
| 547 | tls13_clienthello_hash_finalize(struct tls13_ctx *ctx) | ||
| 548 | { | ||
| 549 | if (!EVP_DigestFinal_ex(ctx->hs->tls13.clienthello_md_ctx, | ||
| 550 | ctx->hs->tls13.clienthello_hash, | ||
| 551 | &ctx->hs->tls13.clienthello_hash_len)) | ||
| 552 | return 0; | ||
| 553 | EVP_MD_CTX_free(ctx->hs->tls13.clienthello_md_ctx); | ||
| 554 | ctx->hs->tls13.clienthello_md_ctx = NULL; | ||
| 555 | return 1; | ||
| 556 | } | ||
| 557 | |||
| 558 | int | ||
| 559 | tls13_clienthello_hash_validate(struct tls13_ctx *ctx) | ||
| 560 | { | ||
| 561 | unsigned char new_ch_hash[EVP_MAX_MD_SIZE]; | ||
| 562 | unsigned int new_ch_hash_len; | ||
| 563 | |||
| 564 | if (ctx->hs->tls13.clienthello_hash == NULL) | ||
| 565 | return 0; | ||
| 566 | |||
| 567 | if (!EVP_DigestFinal_ex(ctx->hs->tls13.clienthello_md_ctx, | ||
| 568 | new_ch_hash, &new_ch_hash_len)) | ||
| 569 | return 0; | ||
| 570 | EVP_MD_CTX_free(ctx->hs->tls13.clienthello_md_ctx); | ||
| 571 | ctx->hs->tls13.clienthello_md_ctx = NULL; | ||
| 572 | |||
| 573 | if (ctx->hs->tls13.clienthello_hash_len != new_ch_hash_len) | ||
| 574 | return 0; | ||
| 575 | if (memcmp(ctx->hs->tls13.clienthello_hash, new_ch_hash, | ||
| 576 | new_ch_hash_len) != 0) | ||
| 577 | return 0; | ||
| 578 | |||
| 579 | return 1; | ||
| 580 | } | ||
| 581 | |||
| 582 | int | ||
| 583 | tls13_exporter(struct tls13_ctx *ctx, const uint8_t *label, size_t label_len, | ||
| 584 | const uint8_t *context_value, size_t context_value_len, uint8_t *out, | ||
| 585 | size_t out_len) | ||
| 586 | { | ||
| 587 | struct tls13_secret context, export_out, export_secret; | ||
| 588 | struct tls13_secrets *secrets = ctx->hs->tls13.secrets; | ||
| 589 | EVP_MD_CTX *md_ctx = NULL; | ||
| 590 | unsigned int md_out_len; | ||
| 591 | int md_len; | ||
| 592 | int ret = 0; | ||
| 593 | |||
| 594 | /* | ||
| 595 | * RFC 8446 Section 7.5. | ||
| 596 | */ | ||
| 597 | |||
| 598 | memset(&context, 0, sizeof(context)); | ||
| 599 | memset(&export_secret, 0, sizeof(export_secret)); | ||
| 600 | |||
| 601 | export_out.data = out; | ||
| 602 | export_out.len = out_len; | ||
| 603 | |||
| 604 | if (!ctx->handshake_completed) | ||
| 605 | return 0; | ||
| 606 | |||
| 607 | md_len = EVP_MD_size(secrets->digest); | ||
| 608 | if (md_len <= 0 || md_len > EVP_MAX_MD_SIZE) | ||
| 609 | goto err; | ||
| 610 | |||
| 611 | if (!tls13_secret_init(&export_secret, md_len)) | ||
| 612 | goto err; | ||
| 613 | if (!tls13_secret_init(&context, md_len)) | ||
| 614 | goto err; | ||
| 615 | |||
| 616 | /* In TLSv1.3 no context is equivalent to an empty context. */ | ||
| 617 | if (context_value == NULL) { | ||
| 618 | context_value = ""; | ||
| 619 | context_value_len = 0; | ||
| 620 | } | ||
| 621 | |||
| 622 | if ((md_ctx = EVP_MD_CTX_new()) == NULL) | ||
| 623 | goto err; | ||
| 624 | if (!EVP_DigestInit_ex(md_ctx, secrets->digest, NULL)) | ||
| 625 | goto err; | ||
| 626 | if (!EVP_DigestUpdate(md_ctx, context_value, context_value_len)) | ||
| 627 | goto err; | ||
| 628 | if (!EVP_DigestFinal_ex(md_ctx, context.data, &md_out_len)) | ||
| 629 | goto err; | ||
| 630 | if (md_len != md_out_len) | ||
| 631 | goto err; | ||
| 632 | |||
| 633 | if (!tls13_derive_secret_with_label_length(&export_secret, | ||
| 634 | secrets->digest, &secrets->exporter_master, label, label_len, | ||
| 635 | &secrets->empty_hash)) | ||
| 636 | goto err; | ||
| 637 | |||
| 638 | if (!tls13_hkdf_expand_label(&export_out, secrets->digest, | ||
| 639 | &export_secret, "exporter", &context)) | ||
| 640 | goto err; | ||
| 641 | |||
| 642 | ret = 1; | ||
| 643 | |||
| 644 | err: | ||
| 645 | EVP_MD_CTX_free(md_ctx); | ||
| 646 | tls13_secret_cleanup(&context); | ||
| 647 | tls13_secret_cleanup(&export_secret); | ||
| 648 | |||
| 649 | return ret; | ||
| 650 | } | ||
