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[thirdparty/openssl.git] / ssl / tls13_enc.c
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34574f19 1/*
6738bf14 2 * Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved.
34574f19 3 *
2c18d164 4 * Licensed under the Apache License 2.0 (the "License"). You may not use
34574f19
MC		 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_locl.h"
08717544 12#include "internal/cryptlib.h"
34574f19
MC		 13#include <openssl/evp.h>
14#include <openssl/kdf.h>
15
0fb2815b 16#define TLS13_MAX_LABEL_LEN 249
34574f19
MC		 17
18/* Always filled with zeros */
19static const unsigned char default_zeros[EVP_MAX_MD_SIZE];
20
34574f19 21/*
a19ae67d
MC		 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|.
0fb2815b
MC		 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.
34574f19 27 */
ec15acb6 28int tls13_hkdf_expand(SSL *s, const EVP_MD *md, const unsigned char *secret,
34574f19 29 const unsigned char *label, size_t labellen,
a19ae67d 30 const unsigned char *data, size_t datalen,
0fb2815b 31 unsigned char *out, size_t outlen, int fatal)
34574f19 32{
48102247 33#ifdef CHARSET_EBCDIC
34 static const unsigned char label_prefix[] = { 0x74, 0x6C, 0x73, 0x31, 0x33, 0x20, 0x00 };
35#else
0fb2815b 36 static const unsigned char label_prefix[] = "tls13 ";
48102247 37#endif
32495464 38 EVP_KDF_CTX *kctx = EVP_KDF_CTX_new_id(EVP_PKEY_HKDF);
34574f19
MC		 39 int ret;
40 size_t hkdflabellen;
41 size_t hashlen;
42 /*
0fb2815b
MC		 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
34574f19
MC		 46 */
47 unsigned char hkdflabel[sizeof(uint16_t) + sizeof(uint8_t) +
0b4233f5 48 + (sizeof(label_prefix) - 1) + TLS13_MAX_LABEL_LEN
0fb2815b 49 + 1 + EVP_MAX_MD_SIZE];
34574f19
MC		 50 WPACKET pkt;
51
32495464 52 if (kctx == NULL)
34574f19
MC		 53 return 0;
54
0fb2815b
MC		 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 }
32495464 66 EVP_KDF_CTX_free(kctx);
0fb2815b
MC		 67 return 0;
68 }
69
34574f19
MC		 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)
a19ae67d 78 || !WPACKET_sub_memcpy_u8(&pkt, data, (data == NULL) ? 0 : datalen)
34574f19
MC		 79 || !WPACKET_get_total_written(&pkt, &hkdflabellen)
80 || !WPACKET_finish(&pkt)) {
32495464 81 EVP_KDF_CTX_free(kctx);
34574f19 82 WPACKET_cleanup(&pkt);
0fb2815b
MC		 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);
34574f19
MC		 88 return 0;
89 }
90
32495464
DM		 91 ret = EVP_KDF_ctrl(kctx, EVP_KDF_CTRL_SET_HKDF_MODE,
92 EVP_PKEY_HKDEF_MODE_EXPAND_ONLY) <= 0
93 || EVP_KDF_ctrl(kctx, EVP_KDF_CTRL_SET_MD, md) <= 0
94 || EVP_KDF_ctrl(kctx, EVP_KDF_CTRL_SET_KEY, secret, hashlen) <= 0
95 || EVP_KDF_ctrl(kctx, EVP_KDF_CTRL_ADD_HKDF_INFO,
96 hkdflabel, hkdflabellen) <= 0
97 || EVP_KDF_derive(kctx, out, outlen) <= 0;
34574f19 98
32495464 99 EVP_KDF_CTX_free(kctx);
34574f19 100
0fb2815b
MC		 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 }
f63a17d6 108
34574f19
MC		 109 return ret == 0;
110}
111
34574f19 112/*
f5ca0b04
MC		 113 * Given a |secret| generate a |key| of length |keylen| bytes. Returns 1 on
114 * success 0 on failure.
34574f19 115 */
d49e23ec
MC		 116int tls13_derive_key(SSL *s, const EVP_MD *md, const unsigned char *secret,
117 unsigned char *key, size_t keylen)
34574f19 118{
48102247 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
f5ca0b04 124
d49e23ec 125 return tls13_hkdf_expand(s, md, secret, keylabel, sizeof(keylabel) - 1,
0fb2815b 126 NULL, 0, key, keylen, 1);
34574f19
MC		 127}
128
129/*
f5ca0b04
MC		 130 * Given a |secret| generate an |iv| of length |ivlen| bytes. Returns 1 on
131 * success 0 on failure.
34574f19 132 */
d49e23ec
MC		 133int tls13_derive_iv(SSL *s, const EVP_MD *md, const unsigned char *secret,
134 unsigned char *iv, size_t ivlen)
34574f19 135{
48102247 136#ifdef CHARSET_EBCDIC
137 static const unsigned char ivlabel[] = { 0x69, 0x76, 0x00 };
138#else
139 static const unsigned char ivlabel[] = "iv";
140#endif
f5ca0b04 141
d49e23ec 142 return tls13_hkdf_expand(s, md, secret, ivlabel, sizeof(ivlabel) - 1,
0fb2815b 143 NULL, 0, iv, ivlen, 1);
34574f19
MC		 144}
145
ec15acb6
MC		 146int tls13_derive_finishedkey(SSL *s, const EVP_MD *md,
147 const unsigned char *secret,
148 unsigned char *fin, size_t finlen)
6484776f 149{
48102247 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
f5ca0b04 155
ec15acb6 156 return tls13_hkdf_expand(s, md, secret, finishedlabel,
0fb2815b 157 sizeof(finishedlabel) - 1, NULL, 0, fin, finlen, 1);
6484776f
MC		 158}
159
34574f19
MC		 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
f5ca0b04 163 * pointed to by |outsecret|. Returns 1 on success 0 on failure.
34574f19 164 */
ec15acb6
MC		 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)
34574f19 170{
34574f19 171 size_t mdlen, prevsecretlen;
bceae201 172 int mdleni;
34574f19 173 int ret;
32495464 174 EVP_KDF_CTX *kctx = EVP_KDF_CTX_new_id(EVP_PKEY_HKDF);
48102247 175#ifdef CHARSET_EBCDIC
176 static const char derived_secret_label[] = { 0x64, 0x65, 0x72, 0x69, 0x76, 0x65, 0x64, 0x00 };
177#else
17aa119e 178 static const char derived_secret_label[] = "derived";
48102247 179#endif
3e0458fb 180 unsigned char preextractsec[EVP_MAX_MD_SIZE];
34574f19 181
32495464 182 if (kctx == NULL) {
f63a17d6
MC		 183 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET,
184 ERR_R_INTERNAL_ERROR);
34574f19 185 return 0;
f63a17d6 186 }
34574f19 187
bceae201
MC		 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);
ad14e8e5 193 EVP_KDF_CTX_free(kctx);
bceae201
MC		 194 return 0;
195 }
196 mdlen = (size_t)mdleni;
34574f19
MC		 197
198 if (insecret == NULL) {
199 insecret = default_zeros;
200 insecretlen = mdlen;
201 }
202 if (prevsecret == NULL) {
203 prevsecret = default_zeros;
204 prevsecretlen = 0;
205 } else {
3e0458fb
MC		 206 EVP_MD_CTX *mctx = EVP_MD_CTX_new();
207 unsigned char hash[EVP_MAX_MD_SIZE];
208
209 /* The pre-extract derive step uses a hash of no messages */
210 if (mctx == NULL
211 || EVP_DigestInit_ex(mctx, md, NULL) <= 0
212 || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) {
f63a17d6
MC		 213 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET,
214 ERR_R_INTERNAL_ERROR);
3e0458fb 215 EVP_MD_CTX_free(mctx);
32495464 216 EVP_KDF_CTX_free(kctx);
3e0458fb
MC		 217 return 0;
218 }
219 EVP_MD_CTX_free(mctx);
220
221 /* Generate the pre-extract secret */
222 if (!tls13_hkdf_expand(s, md, prevsecret,
223 (unsigned char *)derived_secret_label,
a19ae67d 224 sizeof(derived_secret_label) - 1, hash, mdlen,
0fb2815b 225 preextractsec, mdlen, 1)) {
f63a17d6 226 /* SSLfatal() already called */
32495464 227 EVP_KDF_CTX_free(kctx);
3e0458fb 228 return 0;
71d8c138 229 }
3e0458fb
MC		 230
231 prevsecret = preextractsec;
34574f19
MC		 232 prevsecretlen = mdlen;
233 }
234
32495464
DM		 235 ret = EVP_KDF_ctrl(kctx, EVP_KDF_CTRL_SET_HKDF_MODE,
236 EVP_PKEY_HKDEF_MODE_EXTRACT_ONLY) <= 0
237 || EVP_KDF_ctrl(kctx, EVP_KDF_CTRL_SET_MD, md) <= 0
238 || EVP_KDF_ctrl(kctx, EVP_KDF_CTRL_SET_KEY, insecret, insecretlen) <= 0
239 || EVP_KDF_ctrl(kctx, EVP_KDF_CTRL_SET_SALT,
240 prevsecret, prevsecretlen) <= 0
241 || EVP_KDF_derive(kctx, outsecret, mdlen) <= 0;
34574f19 242
f63a17d6
MC		 243 if (ret != 0)
244 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET,
245 ERR_R_INTERNAL_ERROR);
246
32495464 247 EVP_KDF_CTX_free(kctx);
3e0458fb
MC		 248 if (prevsecret == preextractsec)
249 OPENSSL_cleanse(preextractsec, mdlen);
34574f19
MC		 250 return ret == 0;
251}
252
34574f19
MC		 253/*
254 * Given an input secret |insecret| of length |insecretlen| generate the
255 * handshake secret. This requires the early secret to already have been
f5ca0b04 256 * generated. Returns 1 on success 0 on failure.
34574f19
MC		 257 */
258int tls13_generate_handshake_secret(SSL *s, const unsigned char *insecret,
259 size_t insecretlen)
260{
f63a17d6 261 /* Calls SSLfatal() if required */
ec15acb6
MC		 262 return tls13_generate_secret(s, ssl_handshake_md(s), s->early_secret,
263 insecret, insecretlen,
34574f19
MC		 264 (unsigned char *)&s->handshake_secret);
265}
266
267/*
268 * Given the handshake secret |prev| of length |prevlen| generate the master
f5ca0b04
MC		 269 * secret and store its length in |*secret_size|. Returns 1 on success 0 on
270 * failure.
34574f19
MC		 271 */
272int tls13_generate_master_secret(SSL *s, unsigned char *out,
273 unsigned char *prev, size_t prevlen,
274 size_t *secret_size)
275{
ec15acb6
MC		 276 const EVP_MD *md = ssl_handshake_md(s);
277
278 *secret_size = EVP_MD_size(md);
f63a17d6 279 /* Calls SSLfatal() if required */
ec15acb6 280 return tls13_generate_secret(s, md, prev, NULL, 0, out);
34574f19
MC		 281}
282
92760c21 283/*
f5ca0b04
MC		 284 * Generates the mac for the Finished message. Returns the length of the MAC or
285 * 0 on error.
92760c21
MC		 286 */
287size_t tls13_final_finish_mac(SSL *s, const char *str, size_t slen,
288 unsigned char *out)
289{
6484776f
MC		 290 const EVP_MD *md = ssl_handshake_md(s);
291 unsigned char hash[EVP_MAX_MD_SIZE];
292 size_t hashlen, ret = 0;
293 EVP_PKEY *key = NULL;
294 EVP_MD_CTX *ctx = EVP_MD_CTX_new();
92760c21 295
d4d2f3a4
MC		 296 if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) {
297 /* SSLfatal() already called */
6484776f 298 goto err;
d4d2f3a4 299 }
6484776f 300
de9f5b35 301 if (str == s->method->ssl3_enc->server_finished_label) {
f929439f
MC		 302 key = EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC, NULL,
303 s->server_finished_secret, hashlen);
de9f5b35 304 } else if (SSL_IS_FIRST_HANDSHAKE(s)) {
f929439f
MC		 305 key = EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC, NULL,
306 s->client_finished_secret, hashlen);
de9f5b35
MC		 307 } else {
308 unsigned char finsecret[EVP_MAX_MD_SIZE];
309
310 if (!tls13_derive_finishedkey(s, ssl_handshake_md(s),
311 s->client_app_traffic_secret,
312 finsecret, hashlen))
313 goto err;
314
315 key = EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC, NULL, finsecret,
316 hashlen);
8f39d8af 317 OPENSSL_cleanse(finsecret, sizeof(finsecret));
de9f5b35 318 }
6484776f
MC		 319
320 if (key == NULL
321 || ctx == NULL
322 || EVP_DigestSignInit(ctx, NULL, md, NULL, key) <= 0
323 || EVP_DigestSignUpdate(ctx, hash, hashlen) <= 0
d4d2f3a4
MC		 324 || EVP_DigestSignFinal(ctx, out, &hashlen) <= 0) {
325 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_FINAL_FINISH_MAC,
326 ERR_R_INTERNAL_ERROR);
6484776f 327 goto err;
d4d2f3a4 328 }
92760c21 329
6484776f
MC		 330 ret = hashlen;
331 err:
332 EVP_PKEY_free(key);
333 EVP_MD_CTX_free(ctx);
334 return ret;
92760c21
MC		 335}
336
337/*
338 * There isn't really a key block in TLSv1.3, but we still need this function
f5ca0b04 339 * for initialising the cipher and hash. Returns 1 on success or 0 on failure.
92760c21
MC		 340 */
341int tls13_setup_key_block(SSL *s)
342{
343 const EVP_CIPHER *c;
344 const EVP_MD *hash;
92760c21 345
555cbb32 346 s->session->cipher = s->s3.tmp.new_cipher;
ea09abc8 347 if (!ssl_cipher_get_evp(s->session, &c, &hash, NULL, NULL, NULL, 0)) {
f63a17d6
MC		 348 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_SETUP_KEY_BLOCK,
349 SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
92760c21
MC		 350 return 0;
351 }
352
555cbb32
TS		 353 s->s3.tmp.new_sym_enc = c;
354 s->s3.tmp.new_hash = hash;
92760c21
MC		 355
356 return 1;
357}
358
d1186c30 359static int derive_secret_key_and_iv(SSL *s, int sending, const EVP_MD *md,
d49e23ec 360 const EVP_CIPHER *ciph,
57389a32
MC		 361 const unsigned char *insecret,
362 const unsigned char *hash,
363 const unsigned char *label,
364 size_t labellen, unsigned char *secret,
365 unsigned char *iv, EVP_CIPHER_CTX *ciph_ctx)
366{
367 unsigned char key[EVP_MAX_KEY_LENGTH];
368 size_t ivlen, keylen, taglen;
bceae201
MC		 369 int hashleni = EVP_MD_size(md);
370 size_t hashlen;
371
372 /* Ensure cast to size_t is safe */
373 if (!ossl_assert(hashleni >= 0)) {
374 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DERIVE_SECRET_KEY_AND_IV,
375 ERR_R_EVP_LIB);
376 goto err;
377 }
378 hashlen = (size_t)hashleni;
57389a32 379
a19ae67d 380 if (!tls13_hkdf_expand(s, md, insecret, label, labellen, hash, hashlen,
0fb2815b 381 secret, hashlen, 1)) {
f63a17d6 382 /* SSLfatal() already called */
57389a32
MC		 383 goto err;
384 }
385
386 /* TODO(size_t): convert me */
387 keylen = EVP_CIPHER_key_length(ciph);
388 if (EVP_CIPHER_mode(ciph) == EVP_CIPH_CCM_MODE) {
c117af67
MC		 389 uint32_t algenc;
390
57389a32 391 ivlen = EVP_CCM_TLS_IV_LEN;
555cbb32 392 if (s->s3.tmp.new_cipher == NULL) {
c117af67
MC		 393 /* We've not selected a cipher yet - we must be doing early data */
394 algenc = s->session->cipher->algorithm_enc;
395 } else {
555cbb32 396 algenc = s->s3.tmp.new_cipher->algorithm_enc;
c117af67
MC		 397 }
398 if (algenc & (SSL_AES128CCM8 | SSL_AES256CCM8))
57389a32
MC		 399 taglen = EVP_CCM8_TLS_TAG_LEN;
400 else
401 taglen = EVP_CCM_TLS_TAG_LEN;
402 } else {
403 ivlen = EVP_CIPHER_iv_length(ciph);
404 taglen = 0;
405 }
406
d49e23ec
MC		 407 if (!tls13_derive_key(s, md, secret, key, keylen)
408 || !tls13_derive_iv(s, md, secret, iv, ivlen)) {
f63a17d6 409 /* SSLfatal() already called */
57389a32
MC		 410 goto err;
411 }
412
d1186c30 413 if (EVP_CipherInit_ex(ciph_ctx, ciph, NULL, NULL, NULL, sending) <= 0
57389a32
MC		 414 || !EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL)
415 || (taglen != 0 && !EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_TAG,
416 taglen, NULL))
417 || EVP_CipherInit_ex(ciph_ctx, NULL, NULL, key, NULL, -1) <= 0) {
f63a17d6
MC		 418 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DERIVE_SECRET_KEY_AND_IV,
419 ERR_R_EVP_LIB);
57389a32
MC		 420 goto err;
421 }
422
57389a32
MC		 423 return 1;
424 err:
425 OPENSSL_cleanse(key, sizeof(key));
426 return 0;
427}
428
0d9824c1
MC		 429int tls13_change_cipher_state(SSL *s, int which)
430{
48102247 431#ifdef CHARSET_EBCDIC
432 static const unsigned char client_early_traffic[] = {0x63, 0x20, 0x65, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
433 static const unsigned char client_handshake_traffic[] = {0x63, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
434 static const unsigned char client_application_traffic[] = {0x63, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
435 static const unsigned char server_handshake_traffic[] = {0x73, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
436 static const unsigned char server_application_traffic[] = {0x73, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
437 static const unsigned char exporter_master_secret[] = {0x65, 0x78, 0x70, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
438 static const unsigned char resumption_master_secret[] = {0x72, 0x65, 0x73, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
439 static const unsigned char early_exporter_master_secret[] = {0x65, 0x20, 0x65, 0x78, 0x70, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
440#else
17aa119e
MC		 441 static const unsigned char client_early_traffic[] = "c e traffic";
442 static const unsigned char client_handshake_traffic[] = "c hs traffic";
443 static const unsigned char client_application_traffic[] = "c ap traffic";
444 static const unsigned char server_handshake_traffic[] = "s hs traffic";
445 static const unsigned char server_application_traffic[] = "s ap traffic";
0ca8d1ec 446 static const unsigned char exporter_master_secret[] = "exp master";
17aa119e 447 static const unsigned char resumption_master_secret[] = "res master";
b38ede80 448 static const unsigned char early_exporter_master_secret[] = "e exp master";
48102247 449#endif
bebc0c7d 450 unsigned char *iv;
0d9824c1 451 unsigned char secret[EVP_MAX_MD_SIZE];
ace081c1
MC		 452 unsigned char hashval[EVP_MAX_MD_SIZE];
453 unsigned char *hash = hashval;
0d9824c1 454 unsigned char *insecret;
6484776f 455 unsigned char *finsecret = NULL;
2c7bd692 456 const char *log_label = NULL;
0d9824c1 457 EVP_CIPHER_CTX *ciph_ctx;
57389a32 458 size_t finsecretlen = 0;
0d9824c1 459 const unsigned char *label;
ace081c1 460 size_t labellen, hashlen = 0;
6530c490 461 int ret = 0;
42f50fdf
MC		 462 const EVP_MD *md = NULL;
463 const EVP_CIPHER *cipher = NULL;
0d9824c1
MC		 464
465 if (which & SSL3_CC_READ) {
466 if (s->enc_read_ctx != NULL) {
467 EVP_CIPHER_CTX_reset(s->enc_read_ctx);
468 } else {
469 s->enc_read_ctx = EVP_CIPHER_CTX_new();
470 if (s->enc_read_ctx == NULL) {
f63a17d6
MC		 471 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
472 SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
0d9824c1
MC		 473 goto err;
474 }
475 }
476 ciph_ctx = s->enc_read_ctx;
bebc0c7d 477 iv = s->read_iv;
0d9824c1
MC		 478
479 RECORD_LAYER_reset_read_sequence(&s->rlayer);
480 } else {
7426cd34 481 s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
0d9824c1
MC		 482 if (s->enc_write_ctx != NULL) {
483 EVP_CIPHER_CTX_reset(s->enc_write_ctx);
484 } else {
485 s->enc_write_ctx = EVP_CIPHER_CTX_new();
486 if (s->enc_write_ctx == NULL) {
f63a17d6
MC		 487 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
488 SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
0d9824c1
MC		 489 goto err;
490 }
491 }
492 ciph_ctx = s->enc_write_ctx;
bebc0c7d 493 iv = s->write_iv;
0d9824c1
MC		 494
495 RECORD_LAYER_reset_write_sequence(&s->rlayer);
496 }
497
498 if (((which & SSL3_CC_CLIENT) && (which & SSL3_CC_WRITE))
499 || ((which & SSL3_CC_SERVER) && (which & SSL3_CC_READ))) {
d49e23ec
MC		 500 if (which & SSL3_CC_EARLY) {
501 EVP_MD_CTX *mdctx = NULL;
502 long handlen;
503 void *hdata;
504 unsigned int hashlenui;
505 const SSL_CIPHER *sslcipher = SSL_SESSION_get0_cipher(s->session);
506
507 insecret = s->early_secret;
508 label = client_early_traffic;
509 labellen = sizeof(client_early_traffic) - 1;
510 log_label = CLIENT_EARLY_LABEL;
511
555cbb32 512 handlen = BIO_get_mem_data(s->s3.handshake_buffer, &hdata);
d49e23ec 513 if (handlen <= 0) {
f63a17d6
MC		 514 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
515 SSL_F_TLS13_CHANGE_CIPHER_STATE,
516 SSL_R_BAD_HANDSHAKE_LENGTH);
d49e23ec
MC		 517 goto err;
518 }
add8d0e9 519
08717544
MC		 520 if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
521 && s->max_early_data > 0
522 && s->session->ext.max_early_data == 0) {
523 /*
524 * If we are attempting to send early data, and we've decided to
525 * actually do it but max_early_data in s->session is 0 then we
526 * must be using an external PSK.
527 */
528 if (!ossl_assert(s->psksession != NULL
529 && s->max_early_data ==
530 s->psksession->ext.max_early_data)) {
f63a17d6
MC		 531 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
532 SSL_F_TLS13_CHANGE_CIPHER_STATE,
533 ERR_R_INTERNAL_ERROR);
08717544
MC		 534 goto err;
535 }
add8d0e9 536 sslcipher = SSL_SESSION_get0_cipher(s->psksession);
08717544 537 }
d49e23ec 538 if (sslcipher == NULL) {
f63a17d6
MC		 539 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
540 SSL_F_TLS13_CHANGE_CIPHER_STATE, SSL_R_BAD_PSK);
d49e23ec
MC		 541 goto err;
542 }
543
544 /*
545 * We need to calculate the handshake digest using the digest from
546 * the session. We haven't yet selected our ciphersuite so we can't
547 * use ssl_handshake_md().
548 */
549 mdctx = EVP_MD_CTX_new();
550 if (mdctx == NULL) {
f63a17d6
MC		 551 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
552 SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
d49e23ec
MC		 553 goto err;
554 }
555 cipher = EVP_get_cipherbynid(SSL_CIPHER_get_cipher_nid(sslcipher));
556 md = ssl_md(sslcipher->algorithm2);
557 if (md == NULL || !EVP_DigestInit_ex(mdctx, md, NULL)
558 || !EVP_DigestUpdate(mdctx, hdata, handlen)
559 || !EVP_DigestFinal_ex(mdctx, hashval, &hashlenui)) {
f63a17d6
MC		 560 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
561 SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
d49e23ec
MC		 562 EVP_MD_CTX_free(mdctx);
563 goto err;
564 }
565 hashlen = hashlenui;
566 EVP_MD_CTX_free(mdctx);
b38ede80
TT		 567
568 if (!tls13_hkdf_expand(s, md, insecret,
569 early_exporter_master_secret,
570 sizeof(early_exporter_master_secret) - 1,
571 hashval, hashlen,
0fb2815b
MC		 572 s->early_exporter_master_secret, hashlen,
573 1)) {
b38ede80
TT		 574 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
575 SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
576 goto err;
577 }
01a2a654
PW		 578
579 if (!ssl_log_secret(s, EARLY_EXPORTER_SECRET_LABEL,
580 s->early_exporter_master_secret, hashlen)) {
581 /* SSLfatal() already called */
582 goto err;
583 }
d49e23ec 584 } else if (which & SSL3_CC_HANDSHAKE) {
0d9824c1 585 insecret = s->handshake_secret;
6484776f 586 finsecret = s->client_finished_secret;
6612d87b 587 finsecretlen = EVP_MD_size(ssl_handshake_md(s));
0d9824c1
MC		 588 label = client_handshake_traffic;
589 labellen = sizeof(client_handshake_traffic) - 1;
2c7bd692 590 log_label = CLIENT_HANDSHAKE_LABEL;
fe5e20fd 591 /*
69687aa8 592 * The handshake hash used for the server read/client write handshake
f7e393be
MC		 593 * traffic secret is the same as the hash for the server
594 * write/client read handshake traffic secret. However, if we
595 * processed early data then we delay changing the server
596 * read/client write cipher state until later, and the handshake
597 * hashes have moved on. Therefore we use the value saved earlier
598 * when we did the server write/client read change cipher state.
fe5e20fd 599 */
f7e393be 600 hash = s->handshake_traffic_hash;
0d9824c1 601 } else {
ec15acb6 602 insecret = s->master_secret;
0d9824c1
MC		 603 label = client_application_traffic;
604 labellen = sizeof(client_application_traffic) - 1;
2c7bd692 605 log_label = CLIENT_APPLICATION_LABEL;
ace081c1
MC		 606 /*
607 * For this we only use the handshake hashes up until the server
608 * Finished hash. We do not include the client's Finished, which is
609 * what ssl_handshake_hash() would give us. Instead we use the
610 * previously saved value.
611 */
612 hash = s->server_finished_hash;
0d9824c1
MC		 613 }
614 } else {
d49e23ec 615 /* Early data never applies to client-read/server-write */
0d9824c1
MC		 616 if (which & SSL3_CC_HANDSHAKE) {
617 insecret = s->handshake_secret;
6484776f 618 finsecret = s->server_finished_secret;
6612d87b 619 finsecretlen = EVP_MD_size(ssl_handshake_md(s));
0d9824c1
MC		 620 label = server_handshake_traffic;
621 labellen = sizeof(server_handshake_traffic) - 1;
2c7bd692 622 log_label = SERVER_HANDSHAKE_LABEL;
0d9824c1 623 } else {
ec15acb6 624 insecret = s->master_secret;
0d9824c1
MC		 625 label = server_application_traffic;
626 labellen = sizeof(server_application_traffic) - 1;
2c7bd692 627 log_label = SERVER_APPLICATION_LABEL;
0d9824c1
MC		 628 }
629 }
630
d49e23ec
MC		 631 if (!(which & SSL3_CC_EARLY)) {
632 md = ssl_handshake_md(s);
555cbb32 633 cipher = s->s3.tmp.new_sym_enc;
d49e23ec
MC		 634 if (!ssl3_digest_cached_records(s, 1)
635 || !ssl_handshake_hash(s, hashval, sizeof(hashval), &hashlen)) {
f63a17d6 636 /* SSLfatal() already called */;
d49e23ec
MC		 637 goto err;
638 }
ace081c1
MC		 639 }
640
ec15acb6
MC		 641 /*
642 * Save the hash of handshakes up to now for use when we calculate the
643 * client application traffic secret
644 */
645 if (label == server_application_traffic)
646 memcpy(s->server_finished_hash, hashval, hashlen);
647
f7e393be 648 if (label == server_handshake_traffic)
fe5e20fd
MC		 649 memcpy(s->handshake_traffic_hash, hashval, hashlen);
650
ec15acb6
MC		 651 if (label == client_application_traffic) {
652 /*
653 * We also create the resumption master secret, but this time use the
654 * hash for the whole handshake including the Client Finished
655 */
656 if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
657 resumption_master_secret,
658 sizeof(resumption_master_secret) - 1,
4ff1a526 659 hashval, hashlen, s->resumption_master_secret,
0fb2815b 660 hashlen, 1)) {
f63a17d6 661 /* SSLfatal() already called */
ec15acb6
MC		 662 goto err;
663 }
ec15acb6
MC		 664 }
665
d49e23ec
MC		 666 if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, md, cipher,
667 insecret, hash, label, labellen, secret, iv,
668 ciph_ctx)) {
f63a17d6 669 /* SSLfatal() already called */
57389a32 670 goto err;
ec07b1d8 671 }
0d9824c1 672
2221ec10 673 if (label == server_application_traffic) {
57389a32 674 memcpy(s->server_app_traffic_secret, secret, hashlen);
2221ec10
TT		 675 /* Now we create the exporter master secret */
676 if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
677 exporter_master_secret,
678 sizeof(exporter_master_secret) - 1,
679 hash, hashlen, s->exporter_master_secret,
0fb2815b 680 hashlen, 1)) {
2221ec10
TT		 681 /* SSLfatal() already called */
682 goto err;
683 }
6329ce8f
PW		 684
685 if (!ssl_log_secret(s, EXPORTER_SECRET_LABEL, s->exporter_master_secret,
686 hashlen)) {
687 /* SSLfatal() already called */
688 goto err;
689 }
2221ec10 690 } else if (label == client_application_traffic)
57389a32
MC		 691 memcpy(s->client_app_traffic_secret, secret, hashlen);
692
2c7bd692 693 if (!ssl_log_secret(s, log_label, secret, hashlen)) {
f63a17d6 694 /* SSLfatal() already called */
2c7bd692
CB		 695 goto err;
696 }
697
57389a32
MC		 698 if (finsecret != NULL
699 && !tls13_derive_finishedkey(s, ssl_handshake_md(s), secret,
700 finsecret, finsecretlen)) {
f63a17d6 701 /* SSLfatal() already called */
0d9824c1
MC		 702 goto err;
703 }
704
7426cd34
MC		 705 if (!s->server && label == client_early_traffic)
706 s->statem.enc_write_state = ENC_WRITE_STATE_WRITE_PLAIN_ALERTS;
707 else
708 s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
57389a32
MC		 709 ret = 1;
710 err:
711 OPENSSL_cleanse(secret, sizeof(secret));
712 return ret;
713}
0d9824c1 714
d1186c30 715int tls13_update_key(SSL *s, int sending)
57389a32 716{
48102247 717#ifdef CHARSET_EBCDIC
718 static const unsigned char application_traffic[] = { 0x74, 0x72 ,0x61 ,0x66 ,0x66 ,0x69 ,0x63 ,0x20 ,0x75 ,0x70 ,0x64, 0x00};
719#else
720 static const unsigned char application_traffic[] = "traffic upd";
721#endif
57389a32
MC		 722 const EVP_MD *md = ssl_handshake_md(s);
723 size_t hashlen = EVP_MD_size(md);
724 unsigned char *insecret, *iv;
725 unsigned char secret[EVP_MAX_MD_SIZE];
726 EVP_CIPHER_CTX *ciph_ctx;
727 int ret = 0;
0d9824c1 728
d1186c30 729 if (s->server == sending)
57389a32
MC		 730 insecret = s->server_app_traffic_secret;
731 else
732 insecret = s->client_app_traffic_secret;
bebc0c7d 733
d1186c30 734 if (sending) {
7426cd34 735 s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
57389a32
MC		 736 iv = s->write_iv;
737 ciph_ctx = s->enc_write_ctx;
738 RECORD_LAYER_reset_write_sequence(&s->rlayer);
739 } else {
740 iv = s->read_iv;
741 ciph_ctx = s->enc_read_ctx;
742 RECORD_LAYER_reset_read_sequence(&s->rlayer);
0d9824c1 743 }
57389a32 744
d1186c30 745 if (!derive_secret_key_and_iv(s, sending, ssl_handshake_md(s),
555cbb32 746 s->s3.tmp.new_sym_enc, insecret, NULL,
d49e23ec 747 application_traffic,
57389a32 748 sizeof(application_traffic) - 1, secret, iv,
f63a17d6
MC		 749 ciph_ctx)) {
750 /* SSLfatal() already called */
57389a32 751 goto err;
f63a17d6 752 }
57389a32
MC		 753
754 memcpy(insecret, secret, hashlen);
0d9824c1 755
7426cd34 756 s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
6530c490 757 ret = 1;
0d9824c1
MC		 758 err:
759 OPENSSL_cleanse(secret, sizeof(secret));
6530c490 760 return ret;
0d9824c1 761}
04904312
MC		 762
763int tls13_alert_code(int code)
764{
43a0f273
MC		 765 /* There are 2 additional alerts in TLSv1.3 compared to TLSv1.2 */
766 if (code == SSL_AD_MISSING_EXTENSION || code == SSL_AD_CERTIFICATE_REQUIRED)
04904312
MC		 767 return code;
768
769 return tls1_alert_code(code);
770}
0ca8d1ec
MC		 771
772int tls13_export_keying_material(SSL *s, unsigned char *out, size_t olen,
773 const char *label, size_t llen,
774 const unsigned char *context,
775 size_t contextlen, int use_context)
776{
777 unsigned char exportsecret[EVP_MAX_MD_SIZE];
48102247 778#ifdef CHARSET_EBCDIC
779 static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
780#else
0ca8d1ec 781 static const unsigned char exporterlabel[] = "exporter";
48102247 782#endif
c8b93876 783 unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
0ca8d1ec
MC		 784 const EVP_MD *md = ssl_handshake_md(s);
785 EVP_MD_CTX *ctx = EVP_MD_CTX_new();
c8b93876 786 unsigned int hashsize, datalen;
0ca8d1ec
MC		 787 int ret = 0;
788
1f5878b8 789 if (ctx == NULL || !ossl_statem_export_allowed(s))
0ca8d1ec
MC		 790 goto err;
791
792 if (!use_context)
793 contextlen = 0;
794
795 if (EVP_DigestInit_ex(ctx, md, NULL) <= 0
796 || EVP_DigestUpdate(ctx, context, contextlen) <= 0
797 || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
c8b93876
TT		 798 || EVP_DigestInit_ex(ctx, md, NULL) <= 0
799 || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
0ca8d1ec 800 || !tls13_hkdf_expand(s, md, s->exporter_master_secret,
c8b93876 801 (const unsigned char *)label, llen,
0fb2815b 802 data, datalen, exportsecret, hashsize, 0)
0ca8d1ec 803 || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
a19ae67d 804 sizeof(exporterlabel) - 1, hash, hashsize,
0fb2815b 805 out, olen, 0))
0ca8d1ec
MC		 806 goto err;
807
808 ret = 1;
809 err:
810 EVP_MD_CTX_free(ctx);
811 return ret;
812}
b38ede80
TT		 813
814int tls13_export_keying_material_early(SSL *s, unsigned char *out, size_t olen,
815 const char *label, size_t llen,
816 const unsigned char *context,
817 size_t contextlen)
818{
48102247 819#ifdef CHARSET_EBCDIC
820 static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
821#else
822 static const unsigned char exporterlabel[] = "exporter";
823#endif
b38ede80
TT		 824 unsigned char exportsecret[EVP_MAX_MD_SIZE];
825 unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
826 const EVP_MD *md;
827 EVP_MD_CTX *ctx = EVP_MD_CTX_new();
828 unsigned int hashsize, datalen;
829 int ret = 0;
830 const SSL_CIPHER *sslcipher;
831
832 if (ctx == NULL || !ossl_statem_export_early_allowed(s))
833 goto err;
834
835 if (!s->server && s->max_early_data > 0
836 && s->session->ext.max_early_data == 0)
837 sslcipher = SSL_SESSION_get0_cipher(s->psksession);
838 else
839 sslcipher = SSL_SESSION_get0_cipher(s->session);
840
841 md = ssl_md(sslcipher->algorithm2);
842
843 /*
844 * Calculate the hash value and store it in |data|. The reason why
845 * the empty string is used is that the definition of TLS-Exporter
846 * is like so:
847 *
848 * TLS-Exporter(label, context_value, key_length) =
849 * HKDF-Expand-Label(Derive-Secret(Secret, label, ""),
850 * "exporter", Hash(context_value), key_length)
851 *
852 * Derive-Secret(Secret, Label, Messages) =
853 * HKDF-Expand-Label(Secret, Label,
854 * Transcript-Hash(Messages), Hash.length)
855 *
856 * Here Transcript-Hash is the cipher suite hash algorithm.
857 */
858 if (EVP_DigestInit_ex(ctx, md, NULL) <= 0
859 || EVP_DigestUpdate(ctx, context, contextlen) <= 0
860 || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
861 || EVP_DigestInit_ex(ctx, md, NULL) <= 0
862 || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
863 || !tls13_hkdf_expand(s, md, s->early_exporter_master_secret,
864 (const unsigned char *)label, llen,
0fb2815b 865 data, datalen, exportsecret, hashsize, 0)
b38ede80
TT		 866 || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
867 sizeof(exporterlabel) - 1, hash, hashsize,
0fb2815b 868 out, olen, 0))
b38ede80
TT		 869 goto err;
870
871 ret = 1;
872 err:
873 EVP_MD_CTX_free(ctx);
874 return ret;
875}
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