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1 /*
2 * Copyright 2016-2022 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 #include <stdlib.h>
11 #include "ssl_local.h"
12 #include "internal/ktls.h"
13 #include "record/record_local.h"
14 #include "internal/cryptlib.h"
15 #include <openssl/evp.h>
16 #include <openssl/kdf.h>
17 #include <openssl/core_names.h>
18
19 #define TLS13_MAX_LABEL_LEN 249
20
21 #ifdef CHARSET_EBCDIC
22 static const unsigned char label_prefix[] = { 0x74, 0x6C, 0x73, 0x31, 0x33, 0x20, 0x00 };
23 #else
24 static const unsigned char label_prefix[] = "tls13 ";
25 #endif
26
27 /*
28 * Given a |secret|; a |label| of length |labellen|; and |data| of length
29 * |datalen| (e.g. typically a hash of the handshake messages), derive a new
30 * secret |outlen| bytes long and store it in the location pointed to be |out|.
31 * The |data| value may be zero length. Any errors will be treated as fatal if
32 * |fatal| is set. Returns 1 on success 0 on failure.
33 */
34 int tls13_hkdf_expand(SSL_CONNECTION *s, const EVP_MD *md,
35 const unsigned char *secret,
36 const unsigned char *label, size_t labellen,
37 const unsigned char *data, size_t datalen,
38 unsigned char *out, size_t outlen, int fatal)
39 {
40 SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
41 EVP_KDF *kdf = EVP_KDF_fetch(sctx->libctx, OSSL_KDF_NAME_TLS1_3_KDF,
42 sctx->propq);
43 EVP_KDF_CTX *kctx;
44 OSSL_PARAM params[7], *p = params;
45 int mode = EVP_PKEY_HKDEF_MODE_EXPAND_ONLY;
46 const char *mdname = EVP_MD_get0_name(md);
47 int ret;
48 size_t hashlen;
49
50 kctx = EVP_KDF_CTX_new(kdf);
51 EVP_KDF_free(kdf);
52 if (kctx == NULL)
53 return 0;
54
55 if (labellen > TLS13_MAX_LABEL_LEN) {
56 if (fatal) {
57 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
58 } else {
59 /*
60 * Probably we have been called from SSL_export_keying_material(),
61 * or SSL_export_keying_material_early().
62 */
63 ERR_raise(ERR_LIB_SSL, SSL_R_TLS_ILLEGAL_EXPORTER_LABEL);
64 }
65 EVP_KDF_CTX_free(kctx);
66 return 0;
67 }
68
69 if ((ret = EVP_MD_get_size(md)) <= 0) {
70 EVP_KDF_CTX_free(kctx);
71 if (fatal)
72 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
73 else
74 ERR_raise(ERR_LIB_SSL, ERR_R_INTERNAL_ERROR);
75 return 0;
76 }
77 hashlen = (size_t)ret;
78
79 *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE, &mode);
80 *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
81 (char *)mdname, 0);
82 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY,
83 (unsigned char *)secret, hashlen);
84 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PREFIX,
85 (unsigned char *)label_prefix,
86 sizeof(label_prefix) - 1);
87 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_LABEL,
88 (unsigned char *)label, labellen);
89 if (data != NULL)
90 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_DATA,
91 (unsigned char *)data,
92 datalen);
93 *p++ = OSSL_PARAM_construct_end();
94
95 ret = EVP_KDF_derive(kctx, out, outlen, params) <= 0;
96 EVP_KDF_CTX_free(kctx);
97
98 if (ret != 0) {
99 if (fatal)
100 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
101 else
102 ERR_raise(ERR_LIB_SSL, ERR_R_INTERNAL_ERROR);
103 }
104
105 return ret == 0;
106 }
107
108 /*
109 * Given a |secret| generate a |key| of length |keylen| bytes. Returns 1 on
110 * success 0 on failure.
111 */
112 int tls13_derive_key(SSL_CONNECTION *s, const EVP_MD *md,
113 const unsigned char *secret,
114 unsigned char *key, size_t keylen)
115 {
116 #ifdef CHARSET_EBCDIC
117 static const unsigned char keylabel[] ={ 0x6B, 0x65, 0x79, 0x00 };
118 #else
119 static const unsigned char keylabel[] = "key";
120 #endif
121
122 return tls13_hkdf_expand(s, md, secret, keylabel, sizeof(keylabel) - 1,
123 NULL, 0, key, keylen, 1);
124 }
125
126 /*
127 * Given a |secret| generate an |iv| of length |ivlen| bytes. Returns 1 on
128 * success 0 on failure.
129 */
130 int tls13_derive_iv(SSL_CONNECTION *s, const EVP_MD *md,
131 const unsigned char *secret,
132 unsigned char *iv, size_t ivlen)
133 {
134 #ifdef CHARSET_EBCDIC
135 static const unsigned char ivlabel[] = { 0x69, 0x76, 0x00 };
136 #else
137 static const unsigned char ivlabel[] = "iv";
138 #endif
139
140 return tls13_hkdf_expand(s, md, secret, ivlabel, sizeof(ivlabel) - 1,
141 NULL, 0, iv, ivlen, 1);
142 }
143
144 int tls13_derive_finishedkey(SSL_CONNECTION *s, const EVP_MD *md,
145 const unsigned char *secret,
146 unsigned char *fin, size_t finlen)
147 {
148 #ifdef CHARSET_EBCDIC
149 static const unsigned char finishedlabel[] = { 0x66, 0x69, 0x6E, 0x69, 0x73, 0x68, 0x65, 0x64, 0x00 };
150 #else
151 static const unsigned char finishedlabel[] = "finished";
152 #endif
153
154 return tls13_hkdf_expand(s, md, secret, finishedlabel,
155 sizeof(finishedlabel) - 1, NULL, 0, fin, finlen, 1);
156 }
157
158 /*
159 * Given the previous secret |prevsecret| and a new input secret |insecret| of
160 * length |insecretlen|, generate a new secret and store it in the location
161 * pointed to by |outsecret|. Returns 1 on success 0 on failure.
162 */
163 int tls13_generate_secret(SSL_CONNECTION *s, const EVP_MD *md,
164 const unsigned char *prevsecret,
165 const unsigned char *insecret,
166 size_t insecretlen,
167 unsigned char *outsecret)
168 {
169 size_t mdlen;
170 int mdleni;
171 int ret;
172 EVP_KDF *kdf;
173 EVP_KDF_CTX *kctx;
174 OSSL_PARAM params[7], *p = params;
175 int mode = EVP_PKEY_HKDEF_MODE_EXTRACT_ONLY;
176 const char *mdname = EVP_MD_get0_name(md);
177 #ifdef CHARSET_EBCDIC
178 static const char derived_secret_label[] = { 0x64, 0x65, 0x72, 0x69, 0x76, 0x65, 0x64, 0x00 };
179 #else
180 static const char derived_secret_label[] = "derived";
181 #endif
182 SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
183
184 kdf = EVP_KDF_fetch(sctx->libctx, OSSL_KDF_NAME_TLS1_3_KDF, sctx->propq);
185 kctx = EVP_KDF_CTX_new(kdf);
186 EVP_KDF_free(kdf);
187 if (kctx == NULL) {
188 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
189 return 0;
190 }
191
192 mdleni = EVP_MD_get_size(md);
193 /* Ensure cast to size_t is safe */
194 if (!ossl_assert(mdleni >= 0)) {
195 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
196 EVP_KDF_CTX_free(kctx);
197 return 0;
198 }
199 mdlen = (size_t)mdleni;
200
201 *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE, &mode);
202 *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
203 (char *)mdname, 0);
204 if (insecret != NULL)
205 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY,
206 (unsigned char *)insecret,
207 insecretlen);
208 if (prevsecret != NULL)
209 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT,
210 (unsigned char *)prevsecret, mdlen);
211 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PREFIX,
212 (unsigned char *)label_prefix,
213 sizeof(label_prefix) - 1);
214 *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_LABEL,
215 (unsigned char *)derived_secret_label,
216 sizeof(derived_secret_label) - 1);
217 *p++ = OSSL_PARAM_construct_end();
218
219 ret = EVP_KDF_derive(kctx, outsecret, mdlen, params) <= 0;
220
221 if (ret != 0)
222 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
223
224 EVP_KDF_CTX_free(kctx);
225 return ret == 0;
226 }
227
228 /*
229 * Given an input secret |insecret| of length |insecretlen| generate the
230 * handshake secret. This requires the early secret to already have been
231 * generated. Returns 1 on success 0 on failure.
232 */
233 int tls13_generate_handshake_secret(SSL_CONNECTION *s,
234 const unsigned char *insecret,
235 size_t insecretlen)
236 {
237 /* Calls SSLfatal() if required */
238 return tls13_generate_secret(s, ssl_handshake_md(s), s->early_secret,
239 insecret, insecretlen,
240 (unsigned char *)&s->handshake_secret);
241 }
242
243 /*
244 * Given the handshake secret |prev| of length |prevlen| generate the master
245 * secret and store its length in |*secret_size|. Returns 1 on success 0 on
246 * failure.
247 */
248 int tls13_generate_master_secret(SSL_CONNECTION *s, unsigned char *out,
249 unsigned char *prev, size_t prevlen,
250 size_t *secret_size)
251 {
252 const EVP_MD *md = ssl_handshake_md(s);
253
254 *secret_size = EVP_MD_get_size(md);
255 /* Calls SSLfatal() if required */
256 return tls13_generate_secret(s, md, prev, NULL, 0, out);
257 }
258
259 /*
260 * Generates the mac for the Finished message. Returns the length of the MAC or
261 * 0 on error.
262 */
263 size_t tls13_final_finish_mac(SSL_CONNECTION *s, const char *str, size_t slen,
264 unsigned char *out)
265 {
266 const EVP_MD *md = ssl_handshake_md(s);
267 const char *mdname = EVP_MD_get0_name(md);
268 unsigned char hash[EVP_MAX_MD_SIZE];
269 unsigned char finsecret[EVP_MAX_MD_SIZE];
270 unsigned char *key = NULL;
271 size_t len = 0, hashlen;
272 OSSL_PARAM params[2], *p = params;
273 SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
274
275 if (md == NULL)
276 return 0;
277
278 /* Safe to cast away const here since we're not "getting" any data */
279 if (sctx->propq != NULL)
280 *p++ = OSSL_PARAM_construct_utf8_string(OSSL_ALG_PARAM_PROPERTIES,
281 (char *)sctx->propq,
282 0);
283 *p = OSSL_PARAM_construct_end();
284
285 if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) {
286 /* SSLfatal() already called */
287 goto err;
288 }
289
290 if (str == SSL_CONNECTION_GET_SSL(s)->method->ssl3_enc->server_finished_label) {
291 key = s->server_finished_secret;
292 } else if (SSL_IS_FIRST_HANDSHAKE(s)) {
293 key = s->client_finished_secret;
294 } else {
295 if (!tls13_derive_finishedkey(s, md,
296 s->client_app_traffic_secret,
297 finsecret, hashlen))
298 goto err;
299 key = finsecret;
300 }
301
302 if (!EVP_Q_mac(sctx->libctx, "HMAC", sctx->propq, mdname,
303 params, key, hashlen, hash, hashlen,
304 /* outsize as per sizeof(peer_finish_md) */
305 out, EVP_MAX_MD_SIZE * 2, &len)) {
306 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
307 goto err;
308 }
309
310 err:
311 OPENSSL_cleanse(finsecret, sizeof(finsecret));
312 return len;
313 }
314
315 /*
316 * There isn't really a key block in TLSv1.3, but we still need this function
317 * for initialising the cipher and hash. Returns 1 on success or 0 on failure.
318 */
319 int tls13_setup_key_block(SSL_CONNECTION *s)
320 {
321 const EVP_CIPHER *c;
322 const EVP_MD *hash;
323
324 s->session->cipher = s->s3.tmp.new_cipher;
325 if (!ssl_cipher_get_evp(SSL_CONNECTION_GET_CTX(s), s->session, &c, &hash,
326 NULL, NULL, NULL, 0)) {
327 /* Error is already recorded */
328 SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);
329 return 0;
330 }
331
332 ssl_evp_cipher_free(s->s3.tmp.new_sym_enc);
333 s->s3.tmp.new_sym_enc = c;
334 ssl_evp_md_free(s->s3.tmp.new_hash);
335 s->s3.tmp.new_hash = hash;
336
337 return 1;
338 }
339
340 static int derive_secret_key_and_iv(SSL_CONNECTION *s, int sending,
341 const EVP_MD *md,
342 const EVP_CIPHER *ciph,
343 const unsigned char *insecret,
344 const unsigned char *hash,
345 const unsigned char *label,
346 size_t labellen, unsigned char *secret,
347 unsigned char *key, size_t *keylen,
348 unsigned char *iv, size_t *ivlen,
349 size_t *taglen,
350 EVP_CIPHER_CTX *ciph_ctx)
351 {
352 int hashleni = EVP_MD_get_size(md);
353 size_t hashlen;
354 int mode;
355
356 /* Ensure cast to size_t is safe */
357 if (!ossl_assert(hashleni >= 0)) {
358 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
359 return 0;
360 }
361 hashlen = (size_t)hashleni;
362
363 if (!tls13_hkdf_expand(s, md, insecret, label, labellen, hash, hashlen,
364 secret, hashlen, 1)) {
365 /* SSLfatal() already called */
366 return 0;
367 }
368
369 *keylen = EVP_CIPHER_get_key_length(ciph);
370
371 mode = EVP_CIPHER_get_mode(ciph);
372 if (mode == EVP_CIPH_CCM_MODE) {
373 uint32_t algenc;
374
375 *ivlen = EVP_CCM_TLS_IV_LEN;
376 if (s->s3.tmp.new_cipher != NULL) {
377 algenc = s->s3.tmp.new_cipher->algorithm_enc;
378 } else if (s->session->cipher != NULL) {
379 /* We've not selected a cipher yet - we must be doing early data */
380 algenc = s->session->cipher->algorithm_enc;
381 } else if (s->psksession != NULL && s->psksession->cipher != NULL) {
382 /* We must be doing early data with out-of-band PSK */
383 algenc = s->psksession->cipher->algorithm_enc;
384 } else {
385 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
386 return 0;
387 }
388 if (algenc & (SSL_AES128CCM8 | SSL_AES256CCM8))
389 *taglen = EVP_CCM8_TLS_TAG_LEN;
390 else
391 *taglen = EVP_CCM_TLS_TAG_LEN;
392 } else {
393 if (mode == EVP_CIPH_GCM_MODE) {
394 *taglen = EVP_GCM_TLS_TAG_LEN;
395 } else {
396 /* CHACHA20P-POLY1305 */
397 *taglen = EVP_CHACHAPOLY_TLS_TAG_LEN;
398 }
399 *ivlen = EVP_CIPHER_get_iv_length(ciph);
400 }
401
402 if (!tls13_derive_key(s, md, secret, key, *keylen)
403 || !tls13_derive_iv(s, md, secret, iv, *ivlen)) {
404 /* SSLfatal() already called */
405 return 0;
406 }
407
408 if (sending) {
409 if (EVP_CipherInit_ex(ciph_ctx, ciph, NULL, NULL, NULL, sending) <= 0
410 || EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_IVLEN, *ivlen, NULL) <= 0
411 || (mode == EVP_CIPH_CCM_MODE
412 && EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_TAG, *taglen, NULL) <= 0)
413 || EVP_CipherInit_ex(ciph_ctx, NULL, NULL, key, NULL, -1) <= 0) {
414 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
415 return 0;
416 }
417 }
418
419 return 1;
420 }
421
422 int tls13_change_cipher_state(SSL_CONNECTION *s, int which)
423 {
424 #ifdef CHARSET_EBCDIC
425 static const unsigned char client_early_traffic[] = {0x63, 0x20, 0x65, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
426 static const unsigned char client_handshake_traffic[] = {0x63, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
427 static const unsigned char client_application_traffic[] = {0x63, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
428 static const unsigned char server_handshake_traffic[] = {0x73, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
429 static const unsigned char server_application_traffic[] = {0x73, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
430 static const unsigned char exporter_master_secret[] = {0x65, 0x78, 0x70, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
431 static const unsigned char resumption_master_secret[] = {0x72, 0x65, 0x73, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
432 static const unsigned char early_exporter_master_secret[] = {0x65, 0x20, 0x65, 0x78, 0x70, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
433 #else
434 static const unsigned char client_early_traffic[] = "c e traffic";
435 static const unsigned char client_handshake_traffic[] = "c hs traffic";
436 static const unsigned char client_application_traffic[] = "c ap traffic";
437 static const unsigned char server_handshake_traffic[] = "s hs traffic";
438 static const unsigned char server_application_traffic[] = "s ap traffic";
439 static const unsigned char exporter_master_secret[] = "exp master";
440 static const unsigned char resumption_master_secret[] = "res master";
441 static const unsigned char early_exporter_master_secret[] = "e exp master";
442 #endif
443 unsigned char *iv;
444 unsigned char key[EVP_MAX_KEY_LENGTH];
445 unsigned char secret[EVP_MAX_MD_SIZE];
446 unsigned char hashval[EVP_MAX_MD_SIZE];
447 unsigned char *hash = hashval;
448 unsigned char *insecret;
449 unsigned char *finsecret = NULL;
450 const char *log_label = NULL;
451 EVP_CIPHER_CTX *ciph_ctx = NULL;
452 size_t finsecretlen = 0;
453 const unsigned char *label;
454 size_t labellen, hashlen = 0;
455 int ret = 0;
456 const EVP_MD *md = NULL;
457 const EVP_CIPHER *cipher = NULL;
458 SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
459 size_t keylen, ivlen, taglen;
460 #if !defined(OPENSSL_NO_KTLS) && defined(OPENSSL_KTLS_TLS13)
461 ktls_crypto_info_t crypto_info;
462 void *rl_sequence;
463 BIO *bio;
464 #endif
465
466 if (which & SSL3_CC_READ) {
467 iv = s->read_iv;
468
469 RECORD_LAYER_reset_read_sequence(&s->rlayer);
470 } else {
471 s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
472 if (s->enc_write_ctx != NULL) {
473 EVP_CIPHER_CTX_reset(s->enc_write_ctx);
474 } else {
475 s->enc_write_ctx = EVP_CIPHER_CTX_new();
476 if (s->enc_write_ctx == NULL) {
477 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
478 goto err;
479 }
480 }
481 ciph_ctx = s->enc_write_ctx;
482 iv = s->write_iv;
483
484 RECORD_LAYER_reset_write_sequence(&s->rlayer);
485 }
486
487 if (((which & SSL3_CC_CLIENT) && (which & SSL3_CC_WRITE))
488 || ((which & SSL3_CC_SERVER) && (which & SSL3_CC_READ))) {
489 if (which & SSL3_CC_EARLY) {
490 EVP_MD_CTX *mdctx = NULL;
491 long handlen;
492 void *hdata;
493 unsigned int hashlenui;
494 const SSL_CIPHER *sslcipher = SSL_SESSION_get0_cipher(s->session);
495
496 insecret = s->early_secret;
497 label = client_early_traffic;
498 labellen = sizeof(client_early_traffic) - 1;
499 log_label = CLIENT_EARLY_LABEL;
500
501 handlen = BIO_get_mem_data(s->s3.handshake_buffer, &hdata);
502 if (handlen <= 0) {
503 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_LENGTH);
504 goto err;
505 }
506
507 if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
508 && s->max_early_data > 0
509 && s->session->ext.max_early_data == 0) {
510 /*
511 * If we are attempting to send early data, and we've decided to
512 * actually do it but max_early_data in s->session is 0 then we
513 * must be using an external PSK.
514 */
515 if (!ossl_assert(s->psksession != NULL
516 && s->max_early_data ==
517 s->psksession->ext.max_early_data)) {
518 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
519 goto err;
520 }
521 sslcipher = SSL_SESSION_get0_cipher(s->psksession);
522 }
523 if (sslcipher == NULL) {
524 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
525 goto err;
526 }
527
528 /*
529 * We need to calculate the handshake digest using the digest from
530 * the session. We haven't yet selected our ciphersuite so we can't
531 * use ssl_handshake_md().
532 */
533 mdctx = EVP_MD_CTX_new();
534 if (mdctx == NULL) {
535 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
536 goto err;
537 }
538
539 /*
540 * This ups the ref count on cipher so we better make sure we free
541 * it again
542 */
543 if (!ssl_cipher_get_evp_cipher(sctx, sslcipher, &cipher)) {
544 /* Error is already recorded */
545 SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);
546 EVP_MD_CTX_free(mdctx);
547 goto err;
548 }
549
550 md = ssl_md(sctx, sslcipher->algorithm2);
551 if (md == NULL || !EVP_DigestInit_ex(mdctx, md, NULL)
552 || !EVP_DigestUpdate(mdctx, hdata, handlen)
553 || !EVP_DigestFinal_ex(mdctx, hashval, &hashlenui)) {
554 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
555 EVP_MD_CTX_free(mdctx);
556 goto err;
557 }
558 hashlen = hashlenui;
559 EVP_MD_CTX_free(mdctx);
560
561 if (!tls13_hkdf_expand(s, md, insecret,
562 early_exporter_master_secret,
563 sizeof(early_exporter_master_secret) - 1,
564 hashval, hashlen,
565 s->early_exporter_master_secret, hashlen,
566 1)) {
567 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
568 goto err;
569 }
570
571 if (!ssl_log_secret(s, EARLY_EXPORTER_SECRET_LABEL,
572 s->early_exporter_master_secret, hashlen)) {
573 /* SSLfatal() already called */
574 goto err;
575 }
576 } else if (which & SSL3_CC_HANDSHAKE) {
577 insecret = s->handshake_secret;
578 finsecret = s->client_finished_secret;
579 finsecretlen = EVP_MD_get_size(ssl_handshake_md(s));
580 label = client_handshake_traffic;
581 labellen = sizeof(client_handshake_traffic) - 1;
582 log_label = CLIENT_HANDSHAKE_LABEL;
583 /*
584 * The handshake hash used for the server read/client write handshake
585 * traffic secret is the same as the hash for the server
586 * write/client read handshake traffic secret. However, if we
587 * processed early data then we delay changing the server
588 * read/client write cipher state until later, and the handshake
589 * hashes have moved on. Therefore we use the value saved earlier
590 * when we did the server write/client read change cipher state.
591 */
592 hash = s->handshake_traffic_hash;
593 } else {
594 insecret = s->master_secret;
595 label = client_application_traffic;
596 labellen = sizeof(client_application_traffic) - 1;
597 log_label = CLIENT_APPLICATION_LABEL;
598 /*
599 * For this we only use the handshake hashes up until the server
600 * Finished hash. We do not include the client's Finished, which is
601 * what ssl_handshake_hash() would give us. Instead we use the
602 * previously saved value.
603 */
604 hash = s->server_finished_hash;
605 }
606 } else {
607 /* Early data never applies to client-read/server-write */
608 if (which & SSL3_CC_HANDSHAKE) {
609 insecret = s->handshake_secret;
610 finsecret = s->server_finished_secret;
611 finsecretlen = EVP_MD_get_size(ssl_handshake_md(s));
612 label = server_handshake_traffic;
613 labellen = sizeof(server_handshake_traffic) - 1;
614 log_label = SERVER_HANDSHAKE_LABEL;
615 } else {
616 insecret = s->master_secret;
617 label = server_application_traffic;
618 labellen = sizeof(server_application_traffic) - 1;
619 log_label = SERVER_APPLICATION_LABEL;
620 }
621 }
622
623 if (!(which & SSL3_CC_EARLY)) {
624 md = ssl_handshake_md(s);
625 cipher = s->s3.tmp.new_sym_enc;
626 if (!ssl3_digest_cached_records(s, 1)
627 || !ssl_handshake_hash(s, hashval, sizeof(hashval), &hashlen)) {
628 /* SSLfatal() already called */;
629 goto err;
630 }
631 }
632
633 /*
634 * Save the hash of handshakes up to now for use when we calculate the
635 * client application traffic secret
636 */
637 if (label == server_application_traffic)
638 memcpy(s->server_finished_hash, hashval, hashlen);
639
640 if (label == server_handshake_traffic)
641 memcpy(s->handshake_traffic_hash, hashval, hashlen);
642
643 if (label == client_application_traffic) {
644 /*
645 * We also create the resumption master secret, but this time use the
646 * hash for the whole handshake including the Client Finished
647 */
648 if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
649 resumption_master_secret,
650 sizeof(resumption_master_secret) - 1,
651 hashval, hashlen, s->resumption_master_secret,
652 hashlen, 1)) {
653 /* SSLfatal() already called */
654 goto err;
655 }
656 }
657
658 /* check whether cipher is known */
659 if (!ossl_assert(cipher != NULL))
660 goto err;
661
662 if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, md, cipher,
663 insecret, hash, label, labellen, secret, key,
664 &keylen, iv, &ivlen, &taglen, ciph_ctx)) {
665 /* SSLfatal() already called */
666 goto err;
667 }
668
669 if (label == server_application_traffic) {
670 memcpy(s->server_app_traffic_secret, secret, hashlen);
671 /* Now we create the exporter master secret */
672 if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
673 exporter_master_secret,
674 sizeof(exporter_master_secret) - 1,
675 hash, hashlen, s->exporter_master_secret,
676 hashlen, 1)) {
677 /* SSLfatal() already called */
678 goto err;
679 }
680
681 if (!ssl_log_secret(s, EXPORTER_SECRET_LABEL, s->exporter_master_secret,
682 hashlen)) {
683 /* SSLfatal() already called */
684 goto err;
685 }
686 } else if (label == client_application_traffic)
687 memcpy(s->client_app_traffic_secret, secret, hashlen);
688
689 if (!ssl_log_secret(s, log_label, secret, hashlen)) {
690 /* SSLfatal() already called */
691 goto err;
692 }
693
694 if (finsecret != NULL
695 && !tls13_derive_finishedkey(s, ssl_handshake_md(s), secret,
696 finsecret, finsecretlen)) {
697 /* SSLfatal() already called */
698 goto err;
699 }
700
701 if (!s->server && label == client_early_traffic)
702 s->statem.enc_write_state = ENC_WRITE_STATE_WRITE_PLAIN_ALERTS;
703 else
704 s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
705
706 if ((which & SSL3_CC_READ) != 0) {
707 int level = (which & SSL3_CC_EARLY) != 0
708 ? OSSL_RECORD_PROTECTION_LEVEL_EARLY
709 : ((which &SSL3_CC_HANDSHAKE) != 0
710 ? OSSL_RECORD_PROTECTION_LEVEL_HANDSHAKE
711 : OSSL_RECORD_PROTECTION_LEVEL_APPLICATION);
712
713 if (!ssl_set_new_record_layer(s, NULL, s->version,
714 OSSL_RECORD_DIRECTION_READ,
715 level, key, keylen, iv, ivlen, NULL, 0,
716 cipher, taglen, NID_undef, NULL, NULL)) {
717 /* SSLfatal already called */
718 goto err;
719 }
720 }
721
722 #ifndef OPENSSL_NO_KTLS
723 # if defined(OPENSSL_KTLS_TLS13)
724 if (!(which & SSL3_CC_APPLICATION)
725 || (s->options & SSL_OP_ENABLE_KTLS) == 0)
726 goto skip_ktls;
727
728 /* ktls supports only the maximum fragment size */
729 if (ssl_get_max_send_fragment(s) != SSL3_RT_MAX_PLAIN_LENGTH)
730 goto skip_ktls;
731
732 /* ktls does not support record padding */
733 if (s->record_padding_cb != NULL)
734 goto skip_ktls;
735
736 /* check that cipher is supported */
737 if (!ktls_check_supported_cipher(s, cipher, ciph_ctx))
738 goto skip_ktls;
739
740 if (which & SSL3_CC_WRITE)
741 bio = s->wbio;
742 else
743 bio = s->rbio;
744
745 if (!ossl_assert(bio != NULL)) {
746 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
747 goto err;
748 }
749
750 /* All future data will get encrypted by ktls. Flush the BIO or skip ktls */
751 if (which & SSL3_CC_WRITE) {
752 if (BIO_flush(bio) <= 0)
753 goto skip_ktls;
754 }
755
756 /* configure kernel crypto structure */
757 if (which & SSL3_CC_WRITE)
758 rl_sequence = RECORD_LAYER_get_write_sequence(&s->rlayer);
759 else
760 rl_sequence = RECORD_LAYER_get_read_sequence(&s->rlayer);
761
762 if (!ktls_configure_crypto(s, cipher, ciph_ctx, rl_sequence, &crypto_info,
763 which & SSL3_CC_WRITE, iv, key, NULL, 0))
764 goto skip_ktls;
765
766 /* ktls works with user provided buffers directly */
767 if (BIO_set_ktls(bio, &crypto_info, which & SSL3_CC_WRITE)) {
768 if (which & SSL3_CC_WRITE)
769 ssl3_release_write_buffer(s);
770 }
771 skip_ktls:
772 # endif
773 #endif
774 ret = 1;
775 err:
776 if ((which & SSL3_CC_EARLY) != 0) {
777 /* We up-refed this so now we need to down ref */
778 ssl_evp_cipher_free(cipher);
779 }
780 OPENSSL_cleanse(key, sizeof(key));
781 OPENSSL_cleanse(secret, sizeof(secret));
782 return ret;
783 }
784
785 int tls13_update_key(SSL_CONNECTION *s, int sending)
786 {
787 #ifdef CHARSET_EBCDIC
788 static const unsigned char application_traffic[] = { 0x74, 0x72 ,0x61 ,0x66 ,0x66 ,0x69 ,0x63 ,0x20 ,0x75 ,0x70 ,0x64, 0x00};
789 #else
790 static const unsigned char application_traffic[] = "traffic upd";
791 #endif
792 const EVP_MD *md = ssl_handshake_md(s);
793 size_t hashlen = EVP_MD_get_size(md);
794 unsigned char key[EVP_MAX_KEY_LENGTH];
795 unsigned char *insecret, *iv;
796 unsigned char secret[EVP_MAX_MD_SIZE];
797 EVP_CIPHER_CTX *ciph_ctx;
798 size_t keylen, ivlen, taglen;
799 int ret = 0;
800
801 if (s->server == sending)
802 insecret = s->server_app_traffic_secret;
803 else
804 insecret = s->client_app_traffic_secret;
805
806 if (sending) {
807 s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
808 iv = s->write_iv;
809 ciph_ctx = s->enc_write_ctx;
810 RECORD_LAYER_reset_write_sequence(&s->rlayer);
811 } else {
812 iv = s->read_iv;
813 ciph_ctx = s->enc_read_ctx;
814 RECORD_LAYER_reset_read_sequence(&s->rlayer);
815 }
816
817 if (!derive_secret_key_and_iv(s, sending, md,
818 s->s3.tmp.new_sym_enc, insecret, NULL,
819 application_traffic,
820 sizeof(application_traffic) - 1, secret, key,
821 &keylen, iv, &ivlen, &taglen, ciph_ctx)) {
822 /* SSLfatal() already called */
823 goto err;
824 }
825
826 memcpy(insecret, secret, hashlen);
827
828 if (!sending) {
829 if (!ssl_set_new_record_layer(s, NULL, s->version,
830 OSSL_RECORD_DIRECTION_READ,
831 OSSL_RECORD_PROTECTION_LEVEL_APPLICATION,
832 key, keylen, iv, ivlen, NULL, 0,
833 s->s3.tmp.new_sym_enc, taglen, NID_undef, NULL,
834 NULL)) {
835 /* SSLfatal already called */
836 goto err;
837 }
838 }
839
840 s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
841 ret = 1;
842 err:
843 OPENSSL_cleanse(key, sizeof(key));
844 OPENSSL_cleanse(secret, sizeof(secret));
845 return ret;
846 }
847
848 int tls13_alert_code(int code)
849 {
850 /* There are 2 additional alerts in TLSv1.3 compared to TLSv1.2 */
851 if (code == SSL_AD_MISSING_EXTENSION || code == SSL_AD_CERTIFICATE_REQUIRED)
852 return code;
853
854 return tls1_alert_code(code);
855 }
856
857 int tls13_export_keying_material(SSL_CONNECTION *s,
858 unsigned char *out, size_t olen,
859 const char *label, size_t llen,
860 const unsigned char *context,
861 size_t contextlen, int use_context)
862 {
863 unsigned char exportsecret[EVP_MAX_MD_SIZE];
864 #ifdef CHARSET_EBCDIC
865 static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
866 #else
867 static const unsigned char exporterlabel[] = "exporter";
868 #endif
869 unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
870 const EVP_MD *md = ssl_handshake_md(s);
871 EVP_MD_CTX *ctx = EVP_MD_CTX_new();
872 unsigned int hashsize, datalen;
873 int ret = 0;
874
875 if (ctx == NULL || md == NULL || !ossl_statem_export_allowed(s))
876 goto err;
877
878 if (!use_context)
879 contextlen = 0;
880
881 if (EVP_DigestInit_ex(ctx, md, NULL) <= 0
882 || EVP_DigestUpdate(ctx, context, contextlen) <= 0
883 || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
884 || EVP_DigestInit_ex(ctx, md, NULL) <= 0
885 || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
886 || !tls13_hkdf_expand(s, md, s->exporter_master_secret,
887 (const unsigned char *)label, llen,
888 data, datalen, exportsecret, hashsize, 0)
889 || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
890 sizeof(exporterlabel) - 1, hash, hashsize,
891 out, olen, 0))
892 goto err;
893
894 ret = 1;
895 err:
896 EVP_MD_CTX_free(ctx);
897 return ret;
898 }
899
900 int tls13_export_keying_material_early(SSL_CONNECTION *s,
901 unsigned char *out, size_t olen,
902 const char *label, size_t llen,
903 const unsigned char *context,
904 size_t contextlen)
905 {
906 #ifdef CHARSET_EBCDIC
907 static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
908 #else
909 static const unsigned char exporterlabel[] = "exporter";
910 #endif
911 unsigned char exportsecret[EVP_MAX_MD_SIZE];
912 unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
913 const EVP_MD *md;
914 EVP_MD_CTX *ctx = EVP_MD_CTX_new();
915 unsigned int hashsize, datalen;
916 int ret = 0;
917 const SSL_CIPHER *sslcipher;
918
919 if (ctx == NULL || !ossl_statem_export_early_allowed(s))
920 goto err;
921
922 if (!s->server && s->max_early_data > 0
923 && s->session->ext.max_early_data == 0)
924 sslcipher = SSL_SESSION_get0_cipher(s->psksession);
925 else
926 sslcipher = SSL_SESSION_get0_cipher(s->session);
927
928 md = ssl_md(SSL_CONNECTION_GET_CTX(s), sslcipher->algorithm2);
929
930 /*
931 * Calculate the hash value and store it in |data|. The reason why
932 * the empty string is used is that the definition of TLS-Exporter
933 * is like so:
934 *
935 * TLS-Exporter(label, context_value, key_length) =
936 * HKDF-Expand-Label(Derive-Secret(Secret, label, ""),
937 * "exporter", Hash(context_value), key_length)
938 *
939 * Derive-Secret(Secret, Label, Messages) =
940 * HKDF-Expand-Label(Secret, Label,
941 * Transcript-Hash(Messages), Hash.length)
942 *
943 * Here Transcript-Hash is the cipher suite hash algorithm.
944 */
945 if (md == NULL
946 || EVP_DigestInit_ex(ctx, md, NULL) <= 0
947 || EVP_DigestUpdate(ctx, context, contextlen) <= 0
948 || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
949 || EVP_DigestInit_ex(ctx, md, NULL) <= 0
950 || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
951 || !tls13_hkdf_expand(s, md, s->early_exporter_master_secret,
952 (const unsigned char *)label, llen,
953 data, datalen, exportsecret, hashsize, 0)
954 || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
955 sizeof(exporterlabel) - 1, hash, hashsize,
956 out, olen, 0))
957 goto err;
958
959 ret = 1;
960 err:
961 EVP_MD_CTX_free(ctx);
962 return ret;
963 }