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 */
tls13_hkdf_expand(SSL_CONNECTION * s,const EVP_MD * md,const unsigned char * secret,const unsigned char * label,size_t labellen,const unsigned char * data,size_t datalen,unsigned char * out,size_t outlen,int fatal)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 */
tls13_derive_key(SSL_CONNECTION * s,const EVP_MD * md,const unsigned char * secret,unsigned char * key,size_t keylen)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 */
tls13_derive_iv(SSL_CONNECTION * s,const EVP_MD * md,const unsigned char * secret,unsigned char * iv,size_t ivlen)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
tls13_derive_finishedkey(SSL_CONNECTION * s,const EVP_MD * md,const unsigned char * secret,unsigned char * fin,size_t finlen)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 */
tls13_generate_secret(SSL_CONNECTION * s,const EVP_MD * md,const unsigned char * prevsecret,const unsigned char * insecret,size_t insecretlen,unsigned char * outsecret)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 */
tls13_generate_handshake_secret(SSL_CONNECTION * s,const unsigned char * insecret,size_t insecretlen)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 */
tls13_generate_master_secret(SSL_CONNECTION * s,unsigned char * out,unsigned char * prev,size_t prevlen,size_t * secret_size)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 */
tls13_final_finish_mac(SSL_CONNECTION * s,const char * str,size_t slen,unsigned char * out)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 */
tls13_setup_key_block(SSL_CONNECTION * s)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
derive_secret_key_and_iv(SSL_CONNECTION * s,int sending,const EVP_MD * md,const EVP_CIPHER * ciph,const unsigned char * insecret,const unsigned char * hash,const unsigned char * label,size_t labellen,unsigned char * secret,unsigned char * key,size_t * keylen,unsigned char * iv,size_t * ivlen,size_t * taglen,EVP_CIPHER_CTX * ciph_ctx)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 int iivlen;
394
395 if (mode == EVP_CIPH_GCM_MODE) {
396 *taglen = EVP_GCM_TLS_TAG_LEN;
397 } else {
398 /* CHACHA20P-POLY1305 */
399 *taglen = EVP_CHACHAPOLY_TLS_TAG_LEN;
400 }
401 iivlen = EVP_CIPHER_get_iv_length(ciph);
402 if (iivlen < 0) {
403 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
404 return 0;
405 }
406 *ivlen = iivlen;
407 }
408
409 if (!tls13_derive_key(s, md, secret, key, *keylen)
410 || !tls13_derive_iv(s, md, secret, iv, *ivlen)) {
411 /* SSLfatal() already called */
412 return 0;
413 }
414
415 if (sending) {
416 if (EVP_CipherInit_ex(ciph_ctx, ciph, NULL, NULL, NULL, sending) <= 0
417 || EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_IVLEN, *ivlen, NULL) <= 0
418 || (mode == EVP_CIPH_CCM_MODE
419 && EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_TAG, *taglen, NULL) <= 0)
420 || EVP_CipherInit_ex(ciph_ctx, NULL, NULL, key, NULL, -1) <= 0) {
421 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
422 return 0;
423 }
424 }
425
426 return 1;
427 }
428
tls13_change_cipher_state(SSL_CONNECTION * s,int which)429 int tls13_change_cipher_state(SSL_CONNECTION *s, int which)
430 {
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
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";
446 static const unsigned char exporter_master_secret[] = "exp master";
447 static const unsigned char resumption_master_secret[] = "res master";
448 static const unsigned char early_exporter_master_secret[] = "e exp master";
449 #endif
450 unsigned char *iv;
451 unsigned char key[EVP_MAX_KEY_LENGTH];
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 = NULL;
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 SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
466 size_t keylen, ivlen, taglen;
467 #if !defined(OPENSSL_NO_KTLS) && defined(OPENSSL_KTLS_TLS13)
468 ktls_crypto_info_t crypto_info;
469 void *rl_sequence;
470 BIO *bio;
471 #endif
472
473 if (which & SSL3_CC_READ) {
474 iv = s->read_iv;
475 } else {
476 s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
477 if (s->enc_write_ctx != NULL) {
478 EVP_CIPHER_CTX_reset(s->enc_write_ctx);
479 } else {
480 s->enc_write_ctx = EVP_CIPHER_CTX_new();
481 if (s->enc_write_ctx == NULL) {
482 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
483 goto err;
484 }
485 }
486 ciph_ctx = s->enc_write_ctx;
487 iv = s->write_iv;
488
489 RECORD_LAYER_reset_write_sequence(&s->rlayer);
490 }
491
492 if (((which & SSL3_CC_CLIENT) && (which & SSL3_CC_WRITE))
493 || ((which & SSL3_CC_SERVER) && (which & SSL3_CC_READ))) {
494 if (which & SSL3_CC_EARLY) {
495 EVP_MD_CTX *mdctx = NULL;
496 long handlen;
497 void *hdata;
498 unsigned int hashlenui;
499 const SSL_CIPHER *sslcipher = SSL_SESSION_get0_cipher(s->session);
500
501 insecret = s->early_secret;
502 label = client_early_traffic;
503 labellen = sizeof(client_early_traffic) - 1;
504 log_label = CLIENT_EARLY_LABEL;
505
506 handlen = BIO_get_mem_data(s->s3.handshake_buffer, &hdata);
507 if (handlen <= 0) {
508 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_LENGTH);
509 goto err;
510 }
511
512 if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
513 && s->max_early_data > 0
514 && s->session->ext.max_early_data == 0) {
515 /*
516 * If we are attempting to send early data, and we've decided to
517 * actually do it but max_early_data in s->session is 0 then we
518 * must be using an external PSK.
519 */
520 if (!ossl_assert(s->psksession != NULL
521 && s->max_early_data ==
522 s->psksession->ext.max_early_data)) {
523 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
524 goto err;
525 }
526 sslcipher = SSL_SESSION_get0_cipher(s->psksession);
527 }
528 if (sslcipher == NULL) {
529 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
530 goto err;
531 }
532
533 /*
534 * We need to calculate the handshake digest using the digest from
535 * the session. We haven't yet selected our ciphersuite so we can't
536 * use ssl_handshake_md().
537 */
538 mdctx = EVP_MD_CTX_new();
539 if (mdctx == NULL) {
540 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
541 goto err;
542 }
543
544 /*
545 * This ups the ref count on cipher so we better make sure we free
546 * it again
547 */
548 if (!ssl_cipher_get_evp_cipher(sctx, sslcipher, &cipher)) {
549 /* Error is already recorded */
550 SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);
551 EVP_MD_CTX_free(mdctx);
552 goto err;
553 }
554
555 md = ssl_md(sctx, sslcipher->algorithm2);
556 if (md == NULL || !EVP_DigestInit_ex(mdctx, md, NULL)
557 || !EVP_DigestUpdate(mdctx, hdata, handlen)
558 || !EVP_DigestFinal_ex(mdctx, hashval, &hashlenui)) {
559 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
560 EVP_MD_CTX_free(mdctx);
561 goto err;
562 }
563 hashlen = hashlenui;
564 EVP_MD_CTX_free(mdctx);
565
566 if (!tls13_hkdf_expand(s, md, insecret,
567 early_exporter_master_secret,
568 sizeof(early_exporter_master_secret) - 1,
569 hashval, hashlen,
570 s->early_exporter_master_secret, hashlen,
571 1)) {
572 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
573 goto err;
574 }
575
576 if (!ssl_log_secret(s, EARLY_EXPORTER_SECRET_LABEL,
577 s->early_exporter_master_secret, hashlen)) {
578 /* SSLfatal() already called */
579 goto err;
580 }
581 } else if (which & SSL3_CC_HANDSHAKE) {
582 insecret = s->handshake_secret;
583 finsecret = s->client_finished_secret;
584 finsecretlen = EVP_MD_get_size(ssl_handshake_md(s));
585 label = client_handshake_traffic;
586 labellen = sizeof(client_handshake_traffic) - 1;
587 log_label = CLIENT_HANDSHAKE_LABEL;
588 /*
589 * The handshake hash used for the server read/client write handshake
590 * traffic secret is the same as the hash for the server
591 * write/client read handshake traffic secret. However, if we
592 * processed early data then we delay changing the server
593 * read/client write cipher state until later, and the handshake
594 * hashes have moved on. Therefore we use the value saved earlier
595 * when we did the server write/client read change cipher state.
596 */
597 hash = s->handshake_traffic_hash;
598 } else {
599 insecret = s->master_secret;
600 label = client_application_traffic;
601 labellen = sizeof(client_application_traffic) - 1;
602 log_label = CLIENT_APPLICATION_LABEL;
603 /*
604 * For this we only use the handshake hashes up until the server
605 * Finished hash. We do not include the client's Finished, which is
606 * what ssl_handshake_hash() would give us. Instead we use the
607 * previously saved value.
608 */
609 hash = s->server_finished_hash;
610 }
611 } else {
612 /* Early data never applies to client-read/server-write */
613 if (which & SSL3_CC_HANDSHAKE) {
614 insecret = s->handshake_secret;
615 finsecret = s->server_finished_secret;
616 finsecretlen = EVP_MD_get_size(ssl_handshake_md(s));
617 label = server_handshake_traffic;
618 labellen = sizeof(server_handshake_traffic) - 1;
619 log_label = SERVER_HANDSHAKE_LABEL;
620 } else {
621 insecret = s->master_secret;
622 label = server_application_traffic;
623 labellen = sizeof(server_application_traffic) - 1;
624 log_label = SERVER_APPLICATION_LABEL;
625 }
626 }
627
628 if (!(which & SSL3_CC_EARLY)) {
629 md = ssl_handshake_md(s);
630 cipher = s->s3.tmp.new_sym_enc;
631 if (!ssl3_digest_cached_records(s, 1)
632 || !ssl_handshake_hash(s, hashval, sizeof(hashval), &hashlen)) {
633 /* SSLfatal() already called */;
634 goto err;
635 }
636 }
637
638 /*
639 * Save the hash of handshakes up to now for use when we calculate the
640 * client application traffic secret
641 */
642 if (label == server_application_traffic)
643 memcpy(s->server_finished_hash, hashval, hashlen);
644
645 if (label == server_handshake_traffic)
646 memcpy(s->handshake_traffic_hash, hashval, hashlen);
647
648 if (label == client_application_traffic) {
649 /*
650 * We also create the resumption master secret, but this time use the
651 * hash for the whole handshake including the Client Finished
652 */
653 if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
654 resumption_master_secret,
655 sizeof(resumption_master_secret) - 1,
656 hashval, hashlen, s->resumption_master_secret,
657 hashlen, 1)) {
658 /* SSLfatal() already called */
659 goto err;
660 }
661 }
662
663 /* check whether cipher is known */
664 if (!ossl_assert(cipher != NULL))
665 goto err;
666
667 if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, md, cipher,
668 insecret, hash, label, labellen, secret, key,
669 &keylen, iv, &ivlen, &taglen, 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
711 if ((which & SSL3_CC_READ) != 0) {
712 int level = (which & SSL3_CC_EARLY) != 0
713 ? OSSL_RECORD_PROTECTION_LEVEL_EARLY
714 : ((which &SSL3_CC_HANDSHAKE) != 0
715 ? OSSL_RECORD_PROTECTION_LEVEL_HANDSHAKE
716 : OSSL_RECORD_PROTECTION_LEVEL_APPLICATION);
717
718 if (!ssl_set_new_record_layer(s, s->version,
719 OSSL_RECORD_DIRECTION_READ,
720 level, key, keylen, iv, ivlen, NULL, 0,
721 cipher, taglen, NID_undef, NULL, NULL)) {
722 /* SSLfatal already called */
723 goto err;
724 }
725 /* TODO(RECLAYER): Remove me when write rlayer done */
726 goto skip_ktls;
727 }
728
729 #ifndef OPENSSL_NO_KTLS
730 # if defined(OPENSSL_KTLS_TLS13)
731 if (!(which & SSL3_CC_APPLICATION)
732 || (s->options & SSL_OP_ENABLE_KTLS) == 0)
733 goto skip_ktls;
734
735 /* ktls supports only the maximum fragment size */
736 if (ssl_get_max_send_fragment(s) != SSL3_RT_MAX_PLAIN_LENGTH)
737 goto skip_ktls;
738
739 /* ktls does not support record padding */
740 if (s->record_padding_cb != NULL)
741 goto skip_ktls;
742
743 /* check that cipher is supported */
744 if (!ktls_check_supported_cipher(s, cipher, NULL, taglen))
745 goto skip_ktls;
746
747 if (which & SSL3_CC_WRITE)
748 bio = s->wbio;
749 else
750 bio = s->rbio;
751
752 if (!ossl_assert(bio != NULL)) {
753 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
754 goto err;
755 }
756
757 /* All future data will get encrypted by ktls. Flush the BIO or skip ktls */
758 if (which & SSL3_CC_WRITE) {
759 if (BIO_flush(bio) <= 0)
760 goto skip_ktls;
761 }
762
763 /* configure kernel crypto structure */
764 /*
765 * If we get here we are only doing the write side. The read side goes
766 * through the new record layer code.
767 */
768 rl_sequence = RECORD_LAYER_get_write_sequence(&s->rlayer);
769
770 if (!ktls_configure_crypto(sctx->libctx, s->version, cipher, NULL,
771 rl_sequence, &crypto_info, which & SSL3_CC_WRITE,
772 iv, ivlen, key, keylen, NULL, 0))
773 goto skip_ktls;
774
775 /* ktls works with user provided buffers directly */
776 if (BIO_set_ktls(bio, &crypto_info, which & SSL3_CC_WRITE)) {
777 if (which & SSL3_CC_WRITE)
778 ssl3_release_write_buffer(s);
779 }
780 # endif
781 #endif
782 skip_ktls:
783 ret = 1;
784 err:
785 if ((which & SSL3_CC_EARLY) != 0) {
786 /* We up-refed this so now we need to down ref */
787 ssl_evp_cipher_free(cipher);
788 }
789 OPENSSL_cleanse(key, sizeof(key));
790 OPENSSL_cleanse(secret, sizeof(secret));
791 return ret;
792 }
793
tls13_update_key(SSL_CONNECTION * s,int sending)794 int tls13_update_key(SSL_CONNECTION *s, int sending)
795 {
796 #ifdef CHARSET_EBCDIC
797 static const unsigned char application_traffic[] = { 0x74, 0x72 ,0x61 ,0x66 ,0x66 ,0x69 ,0x63 ,0x20 ,0x75 ,0x70 ,0x64, 0x00};
798 #else
799 static const unsigned char application_traffic[] = "traffic upd";
800 #endif
801 const EVP_MD *md = ssl_handshake_md(s);
802 size_t hashlen = EVP_MD_get_size(md);
803 unsigned char key[EVP_MAX_KEY_LENGTH];
804 unsigned char *insecret, *iv;
805 unsigned char secret[EVP_MAX_MD_SIZE];
806 EVP_CIPHER_CTX *ciph_ctx;
807 size_t keylen, ivlen, taglen;
808 int ret = 0;
809
810 if (s->server == sending)
811 insecret = s->server_app_traffic_secret;
812 else
813 insecret = s->client_app_traffic_secret;
814
815 if (sending) {
816 s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
817 iv = s->write_iv;
818 ciph_ctx = s->enc_write_ctx;
819 RECORD_LAYER_reset_write_sequence(&s->rlayer);
820 } else {
821 iv = s->read_iv;
822 ciph_ctx = s->enc_read_ctx;
823 }
824
825 if (!derive_secret_key_and_iv(s, sending, md,
826 s->s3.tmp.new_sym_enc, insecret, NULL,
827 application_traffic,
828 sizeof(application_traffic) - 1, secret, key,
829 &keylen, iv, &ivlen, &taglen, ciph_ctx)) {
830 /* SSLfatal() already called */
831 goto err;
832 }
833
834 memcpy(insecret, secret, hashlen);
835
836 if (!sending) {
837 if (!ssl_set_new_record_layer(s, s->version,
838 OSSL_RECORD_DIRECTION_READ,
839 OSSL_RECORD_PROTECTION_LEVEL_APPLICATION,
840 key, keylen, iv, ivlen, NULL, 0,
841 s->s3.tmp.new_sym_enc, taglen, NID_undef, NULL,
842 NULL)) {
843 /* SSLfatal already called */
844 goto err;
845 }
846 }
847
848 s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
849 ret = 1;
850 err:
851 OPENSSL_cleanse(key, sizeof(key));
852 OPENSSL_cleanse(secret, sizeof(secret));
853 return ret;
854 }
855
tls13_alert_code(int code)856 int tls13_alert_code(int code)
857 {
858 /* There are 2 additional alerts in TLSv1.3 compared to TLSv1.2 */
859 if (code == SSL_AD_MISSING_EXTENSION || code == SSL_AD_CERTIFICATE_REQUIRED)
860 return code;
861
862 return tls1_alert_code(code);
863 }
864
tls13_export_keying_material(SSL_CONNECTION * s,unsigned char * out,size_t olen,const char * label,size_t llen,const unsigned char * context,size_t contextlen,int use_context)865 int tls13_export_keying_material(SSL_CONNECTION *s,
866 unsigned char *out, size_t olen,
867 const char *label, size_t llen,
868 const unsigned char *context,
869 size_t contextlen, int use_context)
870 {
871 unsigned char exportsecret[EVP_MAX_MD_SIZE];
872 #ifdef CHARSET_EBCDIC
873 static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
874 #else
875 static const unsigned char exporterlabel[] = "exporter";
876 #endif
877 unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
878 const EVP_MD *md = ssl_handshake_md(s);
879 EVP_MD_CTX *ctx = EVP_MD_CTX_new();
880 unsigned int hashsize, datalen;
881 int ret = 0;
882
883 if (ctx == NULL || md == NULL || !ossl_statem_export_allowed(s))
884 goto err;
885
886 if (!use_context)
887 contextlen = 0;
888
889 if (EVP_DigestInit_ex(ctx, md, NULL) <= 0
890 || EVP_DigestUpdate(ctx, context, contextlen) <= 0
891 || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
892 || EVP_DigestInit_ex(ctx, md, NULL) <= 0
893 || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
894 || !tls13_hkdf_expand(s, md, s->exporter_master_secret,
895 (const unsigned char *)label, llen,
896 data, datalen, exportsecret, hashsize, 0)
897 || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
898 sizeof(exporterlabel) - 1, hash, hashsize,
899 out, olen, 0))
900 goto err;
901
902 ret = 1;
903 err:
904 EVP_MD_CTX_free(ctx);
905 return ret;
906 }
907
tls13_export_keying_material_early(SSL_CONNECTION * s,unsigned char * out,size_t olen,const char * label,size_t llen,const unsigned char * context,size_t contextlen)908 int tls13_export_keying_material_early(SSL_CONNECTION *s,
909 unsigned char *out, size_t olen,
910 const char *label, size_t llen,
911 const unsigned char *context,
912 size_t contextlen)
913 {
914 #ifdef CHARSET_EBCDIC
915 static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
916 #else
917 static const unsigned char exporterlabel[] = "exporter";
918 #endif
919 unsigned char exportsecret[EVP_MAX_MD_SIZE];
920 unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
921 const EVP_MD *md;
922 EVP_MD_CTX *ctx = EVP_MD_CTX_new();
923 unsigned int hashsize, datalen;
924 int ret = 0;
925 const SSL_CIPHER *sslcipher;
926
927 if (ctx == NULL || !ossl_statem_export_early_allowed(s))
928 goto err;
929
930 if (!s->server && s->max_early_data > 0
931 && s->session->ext.max_early_data == 0)
932 sslcipher = SSL_SESSION_get0_cipher(s->psksession);
933 else
934 sslcipher = SSL_SESSION_get0_cipher(s->session);
935
936 md = ssl_md(SSL_CONNECTION_GET_CTX(s), sslcipher->algorithm2);
937
938 /*
939 * Calculate the hash value and store it in |data|. The reason why
940 * the empty string is used is that the definition of TLS-Exporter
941 * is like so:
942 *
943 * TLS-Exporter(label, context_value, key_length) =
944 * HKDF-Expand-Label(Derive-Secret(Secret, label, ""),
945 * "exporter", Hash(context_value), key_length)
946 *
947 * Derive-Secret(Secret, Label, Messages) =
948 * HKDF-Expand-Label(Secret, Label,
949 * Transcript-Hash(Messages), Hash.length)
950 *
951 * Here Transcript-Hash is the cipher suite hash algorithm.
952 */
953 if (md == NULL
954 || EVP_DigestInit_ex(ctx, md, NULL) <= 0
955 || EVP_DigestUpdate(ctx, context, contextlen) <= 0
956 || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
957 || EVP_DigestInit_ex(ctx, md, NULL) <= 0
958 || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
959 || !tls13_hkdf_expand(s, md, s->early_exporter_master_secret,
960 (const unsigned char *)label, llen,
961 data, datalen, exportsecret, hashsize, 0)
962 || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
963 sizeof(exporterlabel) - 1, hash, hashsize,
964 out, olen, 0))
965 goto err;
966
967 ret = 1;
968 err:
969 EVP_MD_CTX_free(ctx);
970 return ret;
971 }
972
