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source: vbox/trunk/src/libs/openssl-1.1.1g/ssl/tls13_enc.c@ 84032

Last change on this file since 84032 was 83916, checked in by vboxsync, 5 years ago

openssl-1.1.1g: Applied and adjusted our OpenSSL changes to 1.1.1g. bugref:9719

File size: 32.7 KB
Line 
1/*
2 * Copyright 2016-2020 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the OpenSSL license (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/cryptlib.h"
13#include <openssl/evp.h>
14#include <openssl/kdf.h>
15
16#define TLS13_MAX_LABEL_LEN 249
17
18/* Always filled with zeros */
19static const unsigned char default_zeros[EVP_MAX_MD_SIZE];
20
21/*
22 * Given a |secret|; a |label| of length |labellen|; and |data| of length
23 * |datalen| (e.g. typically a hash of the handshake messages), derive a new
24 * secret |outlen| bytes long and store it in the location pointed to be |out|.
25 * The |data| value may be zero length. Any errors will be treated as fatal if
26 * |fatal| is set. Returns 1 on success 0 on failure.
27 */
28int tls13_hkdf_expand(SSL *s, const EVP_MD *md, const unsigned char *secret,
29 const unsigned char *label, size_t labellen,
30 const unsigned char *data, size_t datalen,
31 unsigned char *out, size_t outlen, int fatal)
32{
33#ifdef CHARSET_EBCDIC
34 static const unsigned char label_prefix[] = { 0x74, 0x6C, 0x73, 0x31, 0x33, 0x20, 0x00 };
35#else
36 static const unsigned char label_prefix[] = "tls13 ";
37#endif
38 EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_HKDF, NULL);
39 int ret;
40 size_t hkdflabellen;
41 size_t hashlen;
42 /*
43 * 2 bytes for length of derived secret + 1 byte for length of combined
44 * prefix and label + bytes for the label itself + 1 byte length of hash
45 * + bytes for the hash itself
46 */
47 unsigned char hkdflabel[sizeof(uint16_t) + sizeof(uint8_t)
48 + (sizeof(label_prefix) - 1) + TLS13_MAX_LABEL_LEN
49 + 1 + EVP_MAX_MD_SIZE];
50 WPACKET pkt;
51
52 if (pctx == NULL)
53 return 0;
54
55 if (labellen > TLS13_MAX_LABEL_LEN) {
56 if (fatal) {
57 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_HKDF_EXPAND,
58 ERR_R_INTERNAL_ERROR);
59 } else {
60 /*
61 * Probably we have been called from SSL_export_keying_material(),
62 * or SSL_export_keying_material_early().
63 */
64 SSLerr(SSL_F_TLS13_HKDF_EXPAND, SSL_R_TLS_ILLEGAL_EXPORTER_LABEL);
65 }
66 EVP_PKEY_CTX_free(pctx);
67 return 0;
68 }
69
70 hashlen = EVP_MD_size(md);
71
72 if (!WPACKET_init_static_len(&pkt, hkdflabel, sizeof(hkdflabel), 0)
73 || !WPACKET_put_bytes_u16(&pkt, outlen)
74 || !WPACKET_start_sub_packet_u8(&pkt)
75 || !WPACKET_memcpy(&pkt, label_prefix, sizeof(label_prefix) - 1)
76 || !WPACKET_memcpy(&pkt, label, labellen)
77 || !WPACKET_close(&pkt)
78 || !WPACKET_sub_memcpy_u8(&pkt, data, (data == NULL) ? 0 : datalen)
79 || !WPACKET_get_total_written(&pkt, &hkdflabellen)
80 || !WPACKET_finish(&pkt)) {
81 EVP_PKEY_CTX_free(pctx);
82 WPACKET_cleanup(&pkt);
83 if (fatal)
84 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_HKDF_EXPAND,
85 ERR_R_INTERNAL_ERROR);
86 else
87 SSLerr(SSL_F_TLS13_HKDF_EXPAND, ERR_R_INTERNAL_ERROR);
88 return 0;
89 }
90
91 ret = EVP_PKEY_derive_init(pctx) <= 0
92 || EVP_PKEY_CTX_hkdf_mode(pctx, EVP_PKEY_HKDEF_MODE_EXPAND_ONLY)
93 <= 0
94 || EVP_PKEY_CTX_set_hkdf_md(pctx, md) <= 0
95 || EVP_PKEY_CTX_set1_hkdf_key(pctx, secret, hashlen) <= 0
96 || EVP_PKEY_CTX_add1_hkdf_info(pctx, hkdflabel, hkdflabellen) <= 0
97 || EVP_PKEY_derive(pctx, out, &outlen) <= 0;
98
99 EVP_PKEY_CTX_free(pctx);
100
101 if (ret != 0) {
102 if (fatal)
103 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_HKDF_EXPAND,
104 ERR_R_INTERNAL_ERROR);
105 else
106 SSLerr(SSL_F_TLS13_HKDF_EXPAND, ERR_R_INTERNAL_ERROR);
107 }
108
109 return ret == 0;
110}
111
112/*
113 * Given a |secret| generate a |key| of length |keylen| bytes. Returns 1 on
114 * success 0 on failure.
115 */
116int tls13_derive_key(SSL *s, const EVP_MD *md, const unsigned char *secret,
117 unsigned char *key, size_t keylen)
118{
119#ifdef CHARSET_EBCDIC
120 static const unsigned char keylabel[] ={ 0x6B, 0x65, 0x79, 0x00 };
121#else
122 static const unsigned char keylabel[] = "key";
123#endif
124
125 return tls13_hkdf_expand(s, md, secret, keylabel, sizeof(keylabel) - 1,
126 NULL, 0, key, keylen, 1);
127}
128
129/*
130 * Given a |secret| generate an |iv| of length |ivlen| bytes. Returns 1 on
131 * success 0 on failure.
132 */
133int tls13_derive_iv(SSL *s, const EVP_MD *md, const unsigned char *secret,
134 unsigned char *iv, size_t ivlen)
135{
136#ifdef CHARSET_EBCDIC
137 static const unsigned char ivlabel[] = { 0x69, 0x76, 0x00 };
138#else
139 static const unsigned char ivlabel[] = "iv";
140#endif
141
142 return tls13_hkdf_expand(s, md, secret, ivlabel, sizeof(ivlabel) - 1,
143 NULL, 0, iv, ivlen, 1);
144}
145
146int tls13_derive_finishedkey(SSL *s, const EVP_MD *md,
147 const unsigned char *secret,
148 unsigned char *fin, size_t finlen)
149{
150#ifdef CHARSET_EBCDIC
151 static const unsigned char finishedlabel[] = { 0x66, 0x69, 0x6E, 0x69, 0x73, 0x68, 0x65, 0x64, 0x00 };
152#else
153 static const unsigned char finishedlabel[] = "finished";
154#endif
155
156 return tls13_hkdf_expand(s, md, secret, finishedlabel,
157 sizeof(finishedlabel) - 1, NULL, 0, fin, finlen, 1);
158}
159
160/*
161 * Given the previous secret |prevsecret| and a new input secret |insecret| of
162 * length |insecretlen|, generate a new secret and store it in the location
163 * pointed to by |outsecret|. Returns 1 on success 0 on failure.
164 */
165int tls13_generate_secret(SSL *s, const EVP_MD *md,
166 const unsigned char *prevsecret,
167 const unsigned char *insecret,
168 size_t insecretlen,
169 unsigned char *outsecret)
170{
171 size_t mdlen, prevsecretlen;
172 int mdleni;
173 int ret;
174 EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_HKDF, NULL);
175#ifdef CHARSET_EBCDIC
176 static const char derived_secret_label[] = { 0x64, 0x65, 0x72, 0x69, 0x76, 0x65, 0x64, 0x00 };
177#else
178 static const char derived_secret_label[] = "derived";
179#endif
180 unsigned char preextractsec[EVP_MAX_MD_SIZE];
181
182 if (pctx == NULL) {
183 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET,
184 ERR_R_INTERNAL_ERROR);
185 return 0;
186 }
187
188 mdleni = EVP_MD_size(md);
189 /* Ensure cast to size_t is safe */
190 if (!ossl_assert(mdleni >= 0)) {
191 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET,
192 ERR_R_INTERNAL_ERROR);
193 return 0;
194 }
195 mdlen = (size_t)mdleni;
196
197 if (insecret == NULL) {
198 insecret = default_zeros;
199 insecretlen = mdlen;
200 }
201 if (prevsecret == NULL) {
202 prevsecret = default_zeros;
203 prevsecretlen = 0;
204 } else {
205 EVP_MD_CTX *mctx = EVP_MD_CTX_new();
206 unsigned char hash[EVP_MAX_MD_SIZE];
207
208 /* The pre-extract derive step uses a hash of no messages */
209 if (mctx == NULL
210 || EVP_DigestInit_ex(mctx, md, NULL) <= 0
211 || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) {
212 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET,
213 ERR_R_INTERNAL_ERROR);
214 EVP_MD_CTX_free(mctx);
215 EVP_PKEY_CTX_free(pctx);
216 return 0;
217 }
218 EVP_MD_CTX_free(mctx);
219
220 /* Generate the pre-extract secret */
221 if (!tls13_hkdf_expand(s, md, prevsecret,
222 (unsigned char *)derived_secret_label,
223 sizeof(derived_secret_label) - 1, hash, mdlen,
224 preextractsec, mdlen, 1)) {
225 /* SSLfatal() already called */
226 EVP_PKEY_CTX_free(pctx);
227 return 0;
228 }
229
230 prevsecret = preextractsec;
231 prevsecretlen = mdlen;
232 }
233
234 ret = EVP_PKEY_derive_init(pctx) <= 0
235 || EVP_PKEY_CTX_hkdf_mode(pctx, EVP_PKEY_HKDEF_MODE_EXTRACT_ONLY)
236 <= 0
237 || EVP_PKEY_CTX_set_hkdf_md(pctx, md) <= 0
238 || EVP_PKEY_CTX_set1_hkdf_key(pctx, insecret, insecretlen) <= 0
239 || EVP_PKEY_CTX_set1_hkdf_salt(pctx, prevsecret, prevsecretlen)
240 <= 0
241 || EVP_PKEY_derive(pctx, outsecret, &mdlen)
242 <= 0;
243
244 if (ret != 0)
245 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET,
246 ERR_R_INTERNAL_ERROR);
247
248 EVP_PKEY_CTX_free(pctx);
249 if (prevsecret == preextractsec)
250 OPENSSL_cleanse(preextractsec, mdlen);
251 return ret == 0;
252}
253
254/*
255 * Given an input secret |insecret| of length |insecretlen| generate the
256 * handshake secret. This requires the early secret to already have been
257 * generated. Returns 1 on success 0 on failure.
258 */
259int tls13_generate_handshake_secret(SSL *s, const unsigned char *insecret,
260 size_t insecretlen)
261{
262 /* Calls SSLfatal() if required */
263 return tls13_generate_secret(s, ssl_handshake_md(s), s->early_secret,
264 insecret, insecretlen,
265 (unsigned char *)&s->handshake_secret);
266}
267
268/*
269 * Given the handshake secret |prev| of length |prevlen| generate the master
270 * secret and store its length in |*secret_size|. Returns 1 on success 0 on
271 * failure.
272 */
273int tls13_generate_master_secret(SSL *s, unsigned char *out,
274 unsigned char *prev, size_t prevlen,
275 size_t *secret_size)
276{
277 const EVP_MD *md = ssl_handshake_md(s);
278
279 *secret_size = EVP_MD_size(md);
280 /* Calls SSLfatal() if required */
281 return tls13_generate_secret(s, md, prev, NULL, 0, out);
282}
283
284/*
285 * Generates the mac for the Finished message. Returns the length of the MAC or
286 * 0 on error.
287 */
288size_t tls13_final_finish_mac(SSL *s, const char *str, size_t slen,
289 unsigned char *out)
290{
291 const EVP_MD *md = ssl_handshake_md(s);
292 unsigned char hash[EVP_MAX_MD_SIZE];
293 size_t hashlen, ret = 0;
294 EVP_PKEY *key = NULL;
295 EVP_MD_CTX *ctx = EVP_MD_CTX_new();
296
297 if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) {
298 /* SSLfatal() already called */
299 goto err;
300 }
301
302 if (str == s->method->ssl3_enc->server_finished_label) {
303 key = EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC, NULL,
304 s->server_finished_secret, hashlen);
305 } else if (SSL_IS_FIRST_HANDSHAKE(s)) {
306 key = EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC, NULL,
307 s->client_finished_secret, hashlen);
308 } else {
309 unsigned char finsecret[EVP_MAX_MD_SIZE];
310
311 if (!tls13_derive_finishedkey(s, ssl_handshake_md(s),
312 s->client_app_traffic_secret,
313 finsecret, hashlen))
314 goto err;
315
316 key = EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC, NULL, finsecret,
317 hashlen);
318 OPENSSL_cleanse(finsecret, sizeof(finsecret));
319 }
320
321 if (key == NULL
322 || ctx == NULL
323 || EVP_DigestSignInit(ctx, NULL, md, NULL, key) <= 0
324 || EVP_DigestSignUpdate(ctx, hash, hashlen) <= 0
325 || EVP_DigestSignFinal(ctx, out, &hashlen) <= 0) {
326 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_FINAL_FINISH_MAC,
327 ERR_R_INTERNAL_ERROR);
328 goto err;
329 }
330
331 ret = hashlen;
332 err:
333 EVP_PKEY_free(key);
334 EVP_MD_CTX_free(ctx);
335 return ret;
336}
337
338/*
339 * There isn't really a key block in TLSv1.3, but we still need this function
340 * for initialising the cipher and hash. Returns 1 on success or 0 on failure.
341 */
342int tls13_setup_key_block(SSL *s)
343{
344 const EVP_CIPHER *c;
345 const EVP_MD *hash;
346
347 s->session->cipher = s->s3->tmp.new_cipher;
348 if (!ssl_cipher_get_evp(s->session, &c, &hash, NULL, NULL, NULL, 0)) {
349 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_SETUP_KEY_BLOCK,
350 SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
351 return 0;
352 }
353
354 s->s3->tmp.new_sym_enc = c;
355 s->s3->tmp.new_hash = hash;
356
357 return 1;
358}
359
360static int derive_secret_key_and_iv(SSL *s, int sending, const EVP_MD *md,
361 const EVP_CIPHER *ciph,
362 const unsigned char *insecret,
363 const unsigned char *hash,
364 const unsigned char *label,
365 size_t labellen, unsigned char *secret,
366 unsigned char *iv, EVP_CIPHER_CTX *ciph_ctx)
367{
368 unsigned char key[EVP_MAX_KEY_LENGTH];
369 size_t ivlen, keylen, taglen;
370 int hashleni = EVP_MD_size(md);
371 size_t hashlen;
372
373 /* Ensure cast to size_t is safe */
374 if (!ossl_assert(hashleni >= 0)) {
375 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DERIVE_SECRET_KEY_AND_IV,
376 ERR_R_EVP_LIB);
377 goto err;
378 }
379 hashlen = (size_t)hashleni;
380
381 if (!tls13_hkdf_expand(s, md, insecret, label, labellen, hash, hashlen,
382 secret, hashlen, 1)) {
383 /* SSLfatal() already called */
384 goto err;
385 }
386
387 /* TODO(size_t): convert me */
388 keylen = EVP_CIPHER_key_length(ciph);
389 if (EVP_CIPHER_mode(ciph) == EVP_CIPH_CCM_MODE) {
390 uint32_t algenc;
391
392 ivlen = EVP_CCM_TLS_IV_LEN;
393 if (s->s3->tmp.new_cipher == NULL) {
394 /* We've not selected a cipher yet - we must be doing early data */
395 algenc = s->session->cipher->algorithm_enc;
396 } else {
397 algenc = s->s3->tmp.new_cipher->algorithm_enc;
398 }
399 if (algenc & (SSL_AES128CCM8 | SSL_AES256CCM8))
400 taglen = EVP_CCM8_TLS_TAG_LEN;
401 else
402 taglen = EVP_CCM_TLS_TAG_LEN;
403 } else {
404 ivlen = EVP_CIPHER_iv_length(ciph);
405 taglen = 0;
406 }
407
408 if (!tls13_derive_key(s, md, secret, key, keylen)
409 || !tls13_derive_iv(s, md, secret, iv, ivlen)) {
410 /* SSLfatal() already called */
411 goto err;
412 }
413
414 if (EVP_CipherInit_ex(ciph_ctx, ciph, NULL, NULL, NULL, sending) <= 0
415 || !EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL)
416 || (taglen != 0 && !EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_TAG,
417 taglen, NULL))
418 || EVP_CipherInit_ex(ciph_ctx, NULL, NULL, key, NULL, -1) <= 0) {
419 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DERIVE_SECRET_KEY_AND_IV,
420 ERR_R_EVP_LIB);
421 goto err;
422 }
423
424 return 1;
425 err:
426 OPENSSL_cleanse(key, sizeof(key));
427 return 0;
428}
429
430int tls13_change_cipher_state(SSL *s, int which)
431{
432#ifdef CHARSET_EBCDIC
433 static const unsigned char client_early_traffic[] = {0x63, 0x20, 0x65, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
434 static const unsigned char client_handshake_traffic[] = {0x63, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
435 static const unsigned char client_application_traffic[] = {0x63, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
436 static const unsigned char server_handshake_traffic[] = {0x73, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
437 static const unsigned char server_application_traffic[] = {0x73, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
438 static const unsigned char exporter_master_secret[] = {0x65, 0x78, 0x70, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
439 static const unsigned char resumption_master_secret[] = {0x72, 0x65, 0x73, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
440 static const unsigned char early_exporter_master_secret[] = {0x65, 0x20, 0x65, 0x78, 0x70, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
441#else
442 static const unsigned char client_early_traffic[] = "c e traffic";
443 static const unsigned char client_handshake_traffic[] = "c hs traffic";
444 static const unsigned char client_application_traffic[] = "c ap traffic";
445 static const unsigned char server_handshake_traffic[] = "s hs traffic";
446 static const unsigned char server_application_traffic[] = "s ap traffic";
447 static const unsigned char exporter_master_secret[] = "exp master";
448 static const unsigned char resumption_master_secret[] = "res master";
449 static const unsigned char early_exporter_master_secret[] = "e exp master";
450#endif
451 unsigned char *iv;
452 unsigned char secret[EVP_MAX_MD_SIZE];
453 unsigned char hashval[EVP_MAX_MD_SIZE];
454 unsigned char *hash = hashval;
455 unsigned char *insecret;
456 unsigned char *finsecret = NULL;
457 const char *log_label = NULL;
458 EVP_CIPHER_CTX *ciph_ctx;
459 size_t finsecretlen = 0;
460 const unsigned char *label;
461 size_t labellen, hashlen = 0;
462 int ret = 0;
463 const EVP_MD *md = NULL;
464 const EVP_CIPHER *cipher = NULL;
465
466 if (which & SSL3_CC_READ) {
467 if (s->enc_read_ctx != NULL) {
468 EVP_CIPHER_CTX_reset(s->enc_read_ctx);
469 } else {
470 s->enc_read_ctx = EVP_CIPHER_CTX_new();
471 if (s->enc_read_ctx == NULL) {
472 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
473 SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
474 goto err;
475 }
476 }
477 ciph_ctx = s->enc_read_ctx;
478 iv = s->read_iv;
479
480 RECORD_LAYER_reset_read_sequence(&s->rlayer);
481 } else {
482 s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
483 if (s->enc_write_ctx != NULL) {
484 EVP_CIPHER_CTX_reset(s->enc_write_ctx);
485 } else {
486 s->enc_write_ctx = EVP_CIPHER_CTX_new();
487 if (s->enc_write_ctx == NULL) {
488 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
489 SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
490 goto err;
491 }
492 }
493 ciph_ctx = s->enc_write_ctx;
494 iv = s->write_iv;
495
496 RECORD_LAYER_reset_write_sequence(&s->rlayer);
497 }
498
499 if (((which & SSL3_CC_CLIENT) && (which & SSL3_CC_WRITE))
500 || ((which & SSL3_CC_SERVER) && (which & SSL3_CC_READ))) {
501 if (which & SSL3_CC_EARLY) {
502 EVP_MD_CTX *mdctx = NULL;
503 long handlen;
504 void *hdata;
505 unsigned int hashlenui;
506 const SSL_CIPHER *sslcipher = SSL_SESSION_get0_cipher(s->session);
507
508 insecret = s->early_secret;
509 label = client_early_traffic;
510 labellen = sizeof(client_early_traffic) - 1;
511 log_label = CLIENT_EARLY_LABEL;
512
513 handlen = BIO_get_mem_data(s->s3->handshake_buffer, &hdata);
514 if (handlen <= 0) {
515 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
516 SSL_F_TLS13_CHANGE_CIPHER_STATE,
517 SSL_R_BAD_HANDSHAKE_LENGTH);
518 goto err;
519 }
520
521 if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
522 && s->max_early_data > 0
523 && s->session->ext.max_early_data == 0) {
524 /*
525 * If we are attempting to send early data, and we've decided to
526 * actually do it but max_early_data in s->session is 0 then we
527 * must be using an external PSK.
528 */
529 if (!ossl_assert(s->psksession != NULL
530 && s->max_early_data ==
531 s->psksession->ext.max_early_data)) {
532 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
533 SSL_F_TLS13_CHANGE_CIPHER_STATE,
534 ERR_R_INTERNAL_ERROR);
535 goto err;
536 }
537 sslcipher = SSL_SESSION_get0_cipher(s->psksession);
538 }
539 if (sslcipher == NULL) {
540 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
541 SSL_F_TLS13_CHANGE_CIPHER_STATE, SSL_R_BAD_PSK);
542 goto err;
543 }
544
545 /*
546 * We need to calculate the handshake digest using the digest from
547 * the session. We haven't yet selected our ciphersuite so we can't
548 * use ssl_handshake_md().
549 */
550 mdctx = EVP_MD_CTX_new();
551 if (mdctx == NULL) {
552 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
553 SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
554 goto err;
555 }
556 cipher = EVP_get_cipherbynid(SSL_CIPHER_get_cipher_nid(sslcipher));
557 md = ssl_md(sslcipher->algorithm2);
558 if (md == NULL || !EVP_DigestInit_ex(mdctx, md, NULL)
559 || !EVP_DigestUpdate(mdctx, hdata, handlen)
560 || !EVP_DigestFinal_ex(mdctx, hashval, &hashlenui)) {
561 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
562 SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
563 EVP_MD_CTX_free(mdctx);
564 goto err;
565 }
566 hashlen = hashlenui;
567 EVP_MD_CTX_free(mdctx);
568
569 if (!tls13_hkdf_expand(s, md, insecret,
570 early_exporter_master_secret,
571 sizeof(early_exporter_master_secret) - 1,
572 hashval, hashlen,
573 s->early_exporter_master_secret, hashlen,
574 1)) {
575 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
576 SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
577 goto err;
578 }
579
580 if (!ssl_log_secret(s, EARLY_EXPORTER_SECRET_LABEL,
581 s->early_exporter_master_secret, hashlen)) {
582 /* SSLfatal() already called */
583 goto err;
584 }
585 } else if (which & SSL3_CC_HANDSHAKE) {
586 insecret = s->handshake_secret;
587 finsecret = s->client_finished_secret;
588 finsecretlen = EVP_MD_size(ssl_handshake_md(s));
589 label = client_handshake_traffic;
590 labellen = sizeof(client_handshake_traffic) - 1;
591 log_label = CLIENT_HANDSHAKE_LABEL;
592 /*
593 * The handshake hash used for the server read/client write handshake
594 * traffic secret is the same as the hash for the server
595 * write/client read handshake traffic secret. However, if we
596 * processed early data then we delay changing the server
597 * read/client write cipher state until later, and the handshake
598 * hashes have moved on. Therefore we use the value saved earlier
599 * when we did the server write/client read change cipher state.
600 */
601 hash = s->handshake_traffic_hash;
602 } else {
603 insecret = s->master_secret;
604 label = client_application_traffic;
605 labellen = sizeof(client_application_traffic) - 1;
606 log_label = CLIENT_APPLICATION_LABEL;
607 /*
608 * For this we only use the handshake hashes up until the server
609 * Finished hash. We do not include the client's Finished, which is
610 * what ssl_handshake_hash() would give us. Instead we use the
611 * previously saved value.
612 */
613 hash = s->server_finished_hash;
614 }
615 } else {
616 /* Early data never applies to client-read/server-write */
617 if (which & SSL3_CC_HANDSHAKE) {
618 insecret = s->handshake_secret;
619 finsecret = s->server_finished_secret;
620 finsecretlen = EVP_MD_size(ssl_handshake_md(s));
621 label = server_handshake_traffic;
622 labellen = sizeof(server_handshake_traffic) - 1;
623 log_label = SERVER_HANDSHAKE_LABEL;
624 } else {
625 insecret = s->master_secret;
626 label = server_application_traffic;
627 labellen = sizeof(server_application_traffic) - 1;
628 log_label = SERVER_APPLICATION_LABEL;
629 }
630 }
631
632 if (!(which & SSL3_CC_EARLY)) {
633 md = ssl_handshake_md(s);
634 cipher = s->s3->tmp.new_sym_enc;
635 if (!ssl3_digest_cached_records(s, 1)
636 || !ssl_handshake_hash(s, hashval, sizeof(hashval), &hashlen)) {
637 /* SSLfatal() already called */;
638 goto err;
639 }
640 }
641
642 /*
643 * Save the hash of handshakes up to now for use when we calculate the
644 * client application traffic secret
645 */
646 if (label == server_application_traffic)
647 memcpy(s->server_finished_hash, hashval, hashlen);
648
649 if (label == server_handshake_traffic)
650 memcpy(s->handshake_traffic_hash, hashval, hashlen);
651
652 if (label == client_application_traffic) {
653 /*
654 * We also create the resumption master secret, but this time use the
655 * hash for the whole handshake including the Client Finished
656 */
657 if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
658 resumption_master_secret,
659 sizeof(resumption_master_secret) - 1,
660 hashval, hashlen, s->resumption_master_secret,
661 hashlen, 1)) {
662 /* SSLfatal() already called */
663 goto err;
664 }
665 }
666
667 if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, md, cipher,
668 insecret, hash, label, labellen, secret, iv,
669 ciph_ctx)) {
670 /* SSLfatal() already called */
671 goto err;
672 }
673
674 if (label == server_application_traffic) {
675 memcpy(s->server_app_traffic_secret, secret, hashlen);
676 /* Now we create the exporter master secret */
677 if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
678 exporter_master_secret,
679 sizeof(exporter_master_secret) - 1,
680 hash, hashlen, s->exporter_master_secret,
681 hashlen, 1)) {
682 /* SSLfatal() already called */
683 goto err;
684 }
685
686 if (!ssl_log_secret(s, EXPORTER_SECRET_LABEL, s->exporter_master_secret,
687 hashlen)) {
688 /* SSLfatal() already called */
689 goto err;
690 }
691 } else if (label == client_application_traffic)
692 memcpy(s->client_app_traffic_secret, secret, hashlen);
693
694 if (!ssl_log_secret(s, log_label, secret, hashlen)) {
695 /* SSLfatal() already called */
696 goto err;
697 }
698
699 if (finsecret != NULL
700 && !tls13_derive_finishedkey(s, ssl_handshake_md(s), secret,
701 finsecret, finsecretlen)) {
702 /* SSLfatal() already called */
703 goto err;
704 }
705
706 if (!s->server && label == client_early_traffic)
707 s->statem.enc_write_state = ENC_WRITE_STATE_WRITE_PLAIN_ALERTS;
708 else
709 s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
710 ret = 1;
711 err:
712 OPENSSL_cleanse(secret, sizeof(secret));
713 return ret;
714}
715
716int tls13_update_key(SSL *s, int sending)
717{
718#ifdef CHARSET_EBCDIC
719 static const unsigned char application_traffic[] = { 0x74, 0x72 ,0x61 ,0x66 ,0x66 ,0x69 ,0x63 ,0x20 ,0x75 ,0x70 ,0x64, 0x00};
720#else
721 static const unsigned char application_traffic[] = "traffic upd";
722#endif
723 const EVP_MD *md = ssl_handshake_md(s);
724 size_t hashlen = EVP_MD_size(md);
725 unsigned char *insecret, *iv;
726 unsigned char secret[EVP_MAX_MD_SIZE];
727 EVP_CIPHER_CTX *ciph_ctx;
728 int ret = 0;
729
730 if (s->server == sending)
731 insecret = s->server_app_traffic_secret;
732 else
733 insecret = s->client_app_traffic_secret;
734
735 if (sending) {
736 s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
737 iv = s->write_iv;
738 ciph_ctx = s->enc_write_ctx;
739 RECORD_LAYER_reset_write_sequence(&s->rlayer);
740 } else {
741 iv = s->read_iv;
742 ciph_ctx = s->enc_read_ctx;
743 RECORD_LAYER_reset_read_sequence(&s->rlayer);
744 }
745
746 if (!derive_secret_key_and_iv(s, sending, ssl_handshake_md(s),
747 s->s3->tmp.new_sym_enc, insecret, NULL,
748 application_traffic,
749 sizeof(application_traffic) - 1, secret, iv,
750 ciph_ctx)) {
751 /* SSLfatal() already called */
752 goto err;
753 }
754
755 memcpy(insecret, secret, hashlen);
756
757 s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
758 ret = 1;
759 err:
760 OPENSSL_cleanse(secret, sizeof(secret));
761 return ret;
762}
763
764int tls13_alert_code(int code)
765{
766 /* There are 2 additional alerts in TLSv1.3 compared to TLSv1.2 */
767 if (code == SSL_AD_MISSING_EXTENSION || code == SSL_AD_CERTIFICATE_REQUIRED)
768 return code;
769
770 return tls1_alert_code(code);
771}
772
773int tls13_export_keying_material(SSL *s, unsigned char *out, size_t olen,
774 const char *label, size_t llen,
775 const unsigned char *context,
776 size_t contextlen, int use_context)
777{
778 unsigned char exportsecret[EVP_MAX_MD_SIZE];
779#ifdef CHARSET_EBCDIC
780 static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
781#else
782 static const unsigned char exporterlabel[] = "exporter";
783#endif
784 unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
785 const EVP_MD *md = ssl_handshake_md(s);
786 EVP_MD_CTX *ctx = EVP_MD_CTX_new();
787 unsigned int hashsize, datalen;
788 int ret = 0;
789
790 if (ctx == NULL || !ossl_statem_export_allowed(s))
791 goto err;
792
793 if (!use_context)
794 contextlen = 0;
795
796 if (EVP_DigestInit_ex(ctx, md, NULL) <= 0
797 || EVP_DigestUpdate(ctx, context, contextlen) <= 0
798 || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
799 || EVP_DigestInit_ex(ctx, md, NULL) <= 0
800 || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
801 || !tls13_hkdf_expand(s, md, s->exporter_master_secret,
802 (const unsigned char *)label, llen,
803 data, datalen, exportsecret, hashsize, 0)
804 || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
805 sizeof(exporterlabel) - 1, hash, hashsize,
806 out, olen, 0))
807 goto err;
808
809 ret = 1;
810 err:
811 EVP_MD_CTX_free(ctx);
812 return ret;
813}
814
815int tls13_export_keying_material_early(SSL *s, unsigned char *out, size_t olen,
816 const char *label, size_t llen,
817 const unsigned char *context,
818 size_t contextlen)
819{
820#ifdef CHARSET_EBCDIC
821 static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
822#else
823 static const unsigned char exporterlabel[] = "exporter";
824#endif
825 unsigned char exportsecret[EVP_MAX_MD_SIZE];
826 unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
827 const EVP_MD *md;
828 EVP_MD_CTX *ctx = EVP_MD_CTX_new();
829 unsigned int hashsize, datalen;
830 int ret = 0;
831 const SSL_CIPHER *sslcipher;
832
833 if (ctx == NULL || !ossl_statem_export_early_allowed(s))
834 goto err;
835
836 if (!s->server && s->max_early_data > 0
837 && s->session->ext.max_early_data == 0)
838 sslcipher = SSL_SESSION_get0_cipher(s->psksession);
839 else
840 sslcipher = SSL_SESSION_get0_cipher(s->session);
841
842 md = ssl_md(sslcipher->algorithm2);
843
844 /*
845 * Calculate the hash value and store it in |data|. The reason why
846 * the empty string is used is that the definition of TLS-Exporter
847 * is like so:
848 *
849 * TLS-Exporter(label, context_value, key_length) =
850 * HKDF-Expand-Label(Derive-Secret(Secret, label, ""),
851 * "exporter", Hash(context_value), key_length)
852 *
853 * Derive-Secret(Secret, Label, Messages) =
854 * HKDF-Expand-Label(Secret, Label,
855 * Transcript-Hash(Messages), Hash.length)
856 *
857 * Here Transcript-Hash is the cipher suite hash algorithm.
858 */
859 if (EVP_DigestInit_ex(ctx, md, NULL) <= 0
860 || EVP_DigestUpdate(ctx, context, contextlen) <= 0
861 || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
862 || EVP_DigestInit_ex(ctx, md, NULL) <= 0
863 || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
864 || !tls13_hkdf_expand(s, md, s->early_exporter_master_secret,
865 (const unsigned char *)label, llen,
866 data, datalen, exportsecret, hashsize, 0)
867 || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
868 sizeof(exporterlabel) - 1, hash, hashsize,
869 out, olen, 0))
870 goto err;
871
872 ret = 1;
873 err:
874 EVP_MD_CTX_free(ctx);
875 return ret;
876}
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