2 * Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved.
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
12 #include "internal/cryptlib.h"
13 #include <openssl/evp.h>
14 #include <openssl/kdf.h>
15 #include <openssl/core_names.h>
17 #define TLS13_MAX_LABEL_LEN 249
19 /* Always filled with zeros */
20 static const unsigned char default_zeros
[EVP_MAX_MD_SIZE
];
23 * Given a |secret|; a |label| of length |labellen|; and |data| of length
24 * |datalen| (e.g. typically a hash of the handshake messages), derive a new
25 * secret |outlen| bytes long and store it in the location pointed to be |out|.
26 * The |data| value may be zero length. Any errors will be treated as fatal if
27 * |fatal| is set. Returns 1 on success 0 on failure.
29 int tls13_hkdf_expand(SSL
*s
, const EVP_MD
*md
, const unsigned char *secret
,
30 const unsigned char *label
, size_t labellen
,
31 const unsigned char *data
, size_t datalen
,
32 unsigned char *out
, size_t outlen
, int fatal
)
35 static const unsigned char label_prefix
[] = { 0x74, 0x6C, 0x73, 0x31, 0x33, 0x20, 0x00 };
37 static const unsigned char label_prefix
[] = "tls13 ";
39 EVP_KDF
*kdf
= EVP_KDF_fetch(NULL
, SN_hkdf
, NULL
);
41 OSSL_PARAM params
[5], *p
= params
;
42 int mode
= EVP_PKEY_HKDEF_MODE_EXPAND_ONLY
;
43 const char *mdname
= EVP_MD_name(md
);
48 * 2 bytes for length of derived secret + 1 byte for length of combined
49 * prefix and label + bytes for the label itself + 1 byte length of hash
50 * + bytes for the hash itself
52 unsigned char hkdflabel
[sizeof(uint16_t) + sizeof(uint8_t) +
53 + (sizeof(label_prefix
) - 1) + TLS13_MAX_LABEL_LEN
54 + 1 + EVP_MAX_MD_SIZE
];
57 kctx
= EVP_KDF_CTX_new(kdf
);
62 if (labellen
> TLS13_MAX_LABEL_LEN
) {
64 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS13_HKDF_EXPAND
,
65 ERR_R_INTERNAL_ERROR
);
68 * Probably we have been called from SSL_export_keying_material(),
69 * or SSL_export_keying_material_early().
71 SSLerr(SSL_F_TLS13_HKDF_EXPAND
, SSL_R_TLS_ILLEGAL_EXPORTER_LABEL
);
73 EVP_KDF_CTX_free(kctx
);
77 hashlen
= EVP_MD_size(md
);
79 if (!WPACKET_init_static_len(&pkt
, hkdflabel
, sizeof(hkdflabel
), 0)
80 || !WPACKET_put_bytes_u16(&pkt
, outlen
)
81 || !WPACKET_start_sub_packet_u8(&pkt
)
82 || !WPACKET_memcpy(&pkt
, label_prefix
, sizeof(label_prefix
) - 1)
83 || !WPACKET_memcpy(&pkt
, label
, labellen
)
84 || !WPACKET_close(&pkt
)
85 || !WPACKET_sub_memcpy_u8(&pkt
, data
, (data
== NULL
) ? 0 : datalen
)
86 || !WPACKET_get_total_written(&pkt
, &hkdflabellen
)
87 || !WPACKET_finish(&pkt
)) {
88 EVP_KDF_CTX_free(kctx
);
89 WPACKET_cleanup(&pkt
);
91 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS13_HKDF_EXPAND
,
92 ERR_R_INTERNAL_ERROR
);
94 SSLerr(SSL_F_TLS13_HKDF_EXPAND
, ERR_R_INTERNAL_ERROR
);
98 *p
++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE
, &mode
);
99 *p
++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST
,
100 (char *)mdname
, strlen(mdname
) + 1);
101 *p
++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY
,
102 (unsigned char *)secret
, hashlen
);
103 *p
++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_INFO
,
104 hkdflabel
, hkdflabellen
);
105 *p
++ = OSSL_PARAM_construct_end();
107 ret
= EVP_KDF_CTX_set_params(kctx
, params
) <= 0
108 || EVP_KDF_derive(kctx
, out
, outlen
) <= 0;
110 EVP_KDF_CTX_free(kctx
);
114 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS13_HKDF_EXPAND
,
115 ERR_R_INTERNAL_ERROR
);
117 SSLerr(SSL_F_TLS13_HKDF_EXPAND
, ERR_R_INTERNAL_ERROR
);
124 * Given a |secret| generate a |key| of length |keylen| bytes. Returns 1 on
125 * success 0 on failure.
127 int tls13_derive_key(SSL
*s
, const EVP_MD
*md
, const unsigned char *secret
,
128 unsigned char *key
, size_t keylen
)
130 #ifdef CHARSET_EBCDIC
131 static const unsigned char keylabel
[] ={ 0x6B, 0x65, 0x79, 0x00 };
133 static const unsigned char keylabel
[] = "key";
136 return tls13_hkdf_expand(s
, md
, secret
, keylabel
, sizeof(keylabel
) - 1,
137 NULL
, 0, key
, keylen
, 1);
141 * Given a |secret| generate an |iv| of length |ivlen| bytes. Returns 1 on
142 * success 0 on failure.
144 int tls13_derive_iv(SSL
*s
, const EVP_MD
*md
, const unsigned char *secret
,
145 unsigned char *iv
, size_t ivlen
)
147 #ifdef CHARSET_EBCDIC
148 static const unsigned char ivlabel
[] = { 0x69, 0x76, 0x00 };
150 static const unsigned char ivlabel
[] = "iv";
153 return tls13_hkdf_expand(s
, md
, secret
, ivlabel
, sizeof(ivlabel
) - 1,
154 NULL
, 0, iv
, ivlen
, 1);
157 int tls13_derive_finishedkey(SSL
*s
, const EVP_MD
*md
,
158 const unsigned char *secret
,
159 unsigned char *fin
, size_t finlen
)
161 #ifdef CHARSET_EBCDIC
162 static const unsigned char finishedlabel
[] = { 0x66, 0x69, 0x6E, 0x69, 0x73, 0x68, 0x65, 0x64, 0x00 };
164 static const unsigned char finishedlabel
[] = "finished";
167 return tls13_hkdf_expand(s
, md
, secret
, finishedlabel
,
168 sizeof(finishedlabel
) - 1, NULL
, 0, fin
, finlen
, 1);
172 * Given the previous secret |prevsecret| and a new input secret |insecret| of
173 * length |insecretlen|, generate a new secret and store it in the location
174 * pointed to by |outsecret|. Returns 1 on success 0 on failure.
176 int tls13_generate_secret(SSL
*s
, const EVP_MD
*md
,
177 const unsigned char *prevsecret
,
178 const unsigned char *insecret
,
180 unsigned char *outsecret
)
182 size_t mdlen
, prevsecretlen
;
187 OSSL_PARAM params
[5], *p
= params
;
188 int mode
= EVP_PKEY_HKDEF_MODE_EXTRACT_ONLY
;
189 const char *mdname
= EVP_MD_name(md
);
190 #ifdef CHARSET_EBCDIC
191 static const char derived_secret_label
[] = { 0x64, 0x65, 0x72, 0x69, 0x76, 0x65, 0x64, 0x00 };
193 static const char derived_secret_label
[] = "derived";
195 unsigned char preextractsec
[EVP_MAX_MD_SIZE
];
197 kdf
= EVP_KDF_fetch(NULL
, SN_hkdf
, NULL
);
198 kctx
= EVP_KDF_CTX_new(kdf
);
201 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS13_GENERATE_SECRET
,
202 ERR_R_INTERNAL_ERROR
);
206 mdleni
= EVP_MD_size(md
);
207 /* Ensure cast to size_t is safe */
208 if (!ossl_assert(mdleni
>= 0)) {
209 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS13_GENERATE_SECRET
,
210 ERR_R_INTERNAL_ERROR
);
211 EVP_KDF_CTX_free(kctx
);
214 mdlen
= (size_t)mdleni
;
216 if (insecret
== NULL
) {
217 insecret
= default_zeros
;
220 if (prevsecret
== NULL
) {
221 prevsecret
= default_zeros
;
224 EVP_MD_CTX
*mctx
= EVP_MD_CTX_new();
225 unsigned char hash
[EVP_MAX_MD_SIZE
];
227 /* The pre-extract derive step uses a hash of no messages */
229 || EVP_DigestInit_ex(mctx
, md
, NULL
) <= 0
230 || EVP_DigestFinal_ex(mctx
, hash
, NULL
) <= 0) {
231 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS13_GENERATE_SECRET
,
232 ERR_R_INTERNAL_ERROR
);
233 EVP_MD_CTX_free(mctx
);
234 EVP_KDF_CTX_free(kctx
);
237 EVP_MD_CTX_free(mctx
);
239 /* Generate the pre-extract secret */
240 if (!tls13_hkdf_expand(s
, md
, prevsecret
,
241 (unsigned char *)derived_secret_label
,
242 sizeof(derived_secret_label
) - 1, hash
, mdlen
,
243 preextractsec
, mdlen
, 1)) {
244 /* SSLfatal() already called */
245 EVP_KDF_CTX_free(kctx
);
249 prevsecret
= preextractsec
;
250 prevsecretlen
= mdlen
;
253 *p
++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE
, &mode
);
254 *p
++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST
,
255 (char *)mdname
, strlen(mdname
) + 1);
256 *p
++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY
,
257 (unsigned char *)insecret
,
259 *p
++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT
,
260 (unsigned char *)prevsecret
,
262 *p
++ = OSSL_PARAM_construct_end();
264 ret
= EVP_KDF_CTX_set_params(kctx
, params
) <= 0
265 || EVP_KDF_derive(kctx
, outsecret
, mdlen
) <= 0;
268 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS13_GENERATE_SECRET
,
269 ERR_R_INTERNAL_ERROR
);
271 EVP_KDF_CTX_free(kctx
);
272 if (prevsecret
== preextractsec
)
273 OPENSSL_cleanse(preextractsec
, mdlen
);
278 * Given an input secret |insecret| of length |insecretlen| generate the
279 * handshake secret. This requires the early secret to already have been
280 * generated. Returns 1 on success 0 on failure.
282 int tls13_generate_handshake_secret(SSL
*s
, const unsigned char *insecret
,
285 /* Calls SSLfatal() if required */
286 return tls13_generate_secret(s
, ssl_handshake_md(s
), s
->early_secret
,
287 insecret
, insecretlen
,
288 (unsigned char *)&s
->handshake_secret
);
292 * Given the handshake secret |prev| of length |prevlen| generate the master
293 * secret and store its length in |*secret_size|. Returns 1 on success 0 on
296 int tls13_generate_master_secret(SSL
*s
, unsigned char *out
,
297 unsigned char *prev
, size_t prevlen
,
300 const EVP_MD
*md
= ssl_handshake_md(s
);
302 *secret_size
= EVP_MD_size(md
);
303 /* Calls SSLfatal() if required */
304 return tls13_generate_secret(s
, md
, prev
, NULL
, 0, out
);
308 * Generates the mac for the Finished message. Returns the length of the MAC or
311 size_t tls13_final_finish_mac(SSL
*s
, const char *str
, size_t slen
,
314 const EVP_MD
*md
= ssl_handshake_md(s
);
315 unsigned char hash
[EVP_MAX_MD_SIZE
];
316 size_t hashlen
, ret
= 0;
317 EVP_PKEY
*key
= NULL
;
318 EVP_MD_CTX
*ctx
= EVP_MD_CTX_new();
320 if (!ssl_handshake_hash(s
, hash
, sizeof(hash
), &hashlen
)) {
321 /* SSLfatal() already called */
325 if (str
== s
->method
->ssl3_enc
->server_finished_label
) {
326 key
= EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC
, NULL
,
327 s
->server_finished_secret
, hashlen
);
328 } else if (SSL_IS_FIRST_HANDSHAKE(s
)) {
329 key
= EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC
, NULL
,
330 s
->client_finished_secret
, hashlen
);
332 unsigned char finsecret
[EVP_MAX_MD_SIZE
];
334 if (!tls13_derive_finishedkey(s
, ssl_handshake_md(s
),
335 s
->client_app_traffic_secret
,
339 key
= EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC
, NULL
, finsecret
,
341 OPENSSL_cleanse(finsecret
, sizeof(finsecret
));
346 || EVP_DigestSignInit(ctx
, NULL
, md
, NULL
, key
) <= 0
347 || EVP_DigestSignUpdate(ctx
, hash
, hashlen
) <= 0
348 || EVP_DigestSignFinal(ctx
, out
, &hashlen
) <= 0) {
349 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS13_FINAL_FINISH_MAC
,
350 ERR_R_INTERNAL_ERROR
);
357 EVP_MD_CTX_free(ctx
);
362 * There isn't really a key block in TLSv1.3, but we still need this function
363 * for initialising the cipher and hash. Returns 1 on success or 0 on failure.
365 int tls13_setup_key_block(SSL
*s
)
370 s
->session
->cipher
= s
->s3
.tmp
.new_cipher
;
371 if (!ssl_cipher_get_evp(s
->session
, &c
, &hash
, NULL
, NULL
, NULL
, 0)) {
372 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_TLS13_SETUP_KEY_BLOCK
,
373 SSL_R_CIPHER_OR_HASH_UNAVAILABLE
);
377 s
->s3
.tmp
.new_sym_enc
= c
;
378 s
->s3
.tmp
.new_hash
= hash
;
383 static int derive_secret_key_and_iv(SSL
*s
, int sending
, const EVP_MD
*md
,
384 const EVP_CIPHER
*ciph
,
385 const unsigned char *insecret
,
386 const unsigned char *hash
,
387 const unsigned char *label
,
388 size_t labellen
, unsigned char *secret
,
389 unsigned char *iv
, EVP_CIPHER_CTX
*ciph_ctx
)
391 unsigned char key
[EVP_MAX_KEY_LENGTH
];
392 size_t ivlen
, keylen
, taglen
;
393 int hashleni
= EVP_MD_size(md
);
396 /* Ensure cast to size_t is safe */
397 if (!ossl_assert(hashleni
>= 0)) {
398 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_DERIVE_SECRET_KEY_AND_IV
,
402 hashlen
= (size_t)hashleni
;
404 if (!tls13_hkdf_expand(s
, md
, insecret
, label
, labellen
, hash
, hashlen
,
405 secret
, hashlen
, 1)) {
406 /* SSLfatal() already called */
410 /* TODO(size_t): convert me */
411 keylen
= EVP_CIPHER_key_length(ciph
);
412 if (EVP_CIPHER_mode(ciph
) == EVP_CIPH_CCM_MODE
) {
415 ivlen
= EVP_CCM_TLS_IV_LEN
;
416 if (s
->s3
.tmp
.new_cipher
== NULL
) {
417 /* We've not selected a cipher yet - we must be doing early data */
418 algenc
= s
->session
->cipher
->algorithm_enc
;
420 algenc
= s
->s3
.tmp
.new_cipher
->algorithm_enc
;
422 if (algenc
& (SSL_AES128CCM8
| SSL_AES256CCM8
))
423 taglen
= EVP_CCM8_TLS_TAG_LEN
;
425 taglen
= EVP_CCM_TLS_TAG_LEN
;
427 ivlen
= EVP_CIPHER_iv_length(ciph
);
431 if (!tls13_derive_key(s
, md
, secret
, key
, keylen
)
432 || !tls13_derive_iv(s
, md
, secret
, iv
, ivlen
)) {
433 /* SSLfatal() already called */
437 if (EVP_CipherInit_ex(ciph_ctx
, ciph
, NULL
, NULL
, NULL
, sending
) <= 0
438 || !EVP_CIPHER_CTX_ctrl(ciph_ctx
, EVP_CTRL_AEAD_SET_IVLEN
, ivlen
, NULL
)
439 || (taglen
!= 0 && !EVP_CIPHER_CTX_ctrl(ciph_ctx
, EVP_CTRL_AEAD_SET_TAG
,
441 || EVP_CipherInit_ex(ciph_ctx
, NULL
, NULL
, key
, NULL
, -1) <= 0) {
442 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
, SSL_F_DERIVE_SECRET_KEY_AND_IV
,
449 OPENSSL_cleanse(key
, sizeof(key
));
453 int tls13_change_cipher_state(SSL
*s
, int which
)
455 #ifdef CHARSET_EBCDIC
456 static const unsigned char client_early_traffic
[] = {0x63, 0x20, 0x65, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
457 static const unsigned char client_handshake_traffic
[] = {0x63, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
458 static const unsigned char client_application_traffic
[] = {0x63, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
459 static const unsigned char server_handshake_traffic
[] = {0x73, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
460 static const unsigned char server_application_traffic
[] = {0x73, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
461 static const unsigned char exporter_master_secret
[] = {0x65, 0x78, 0x70, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
462 static const unsigned char resumption_master_secret
[] = {0x72, 0x65, 0x73, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
463 static const unsigned char early_exporter_master_secret
[] = {0x65, 0x20, 0x65, 0x78, 0x70, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
465 static const unsigned char client_early_traffic
[] = "c e traffic";
466 static const unsigned char client_handshake_traffic
[] = "c hs traffic";
467 static const unsigned char client_application_traffic
[] = "c ap traffic";
468 static const unsigned char server_handshake_traffic
[] = "s hs traffic";
469 static const unsigned char server_application_traffic
[] = "s ap traffic";
470 static const unsigned char exporter_master_secret
[] = "exp master";
471 static const unsigned char resumption_master_secret
[] = "res master";
472 static const unsigned char early_exporter_master_secret
[] = "e exp master";
475 unsigned char secret
[EVP_MAX_MD_SIZE
];
476 unsigned char hashval
[EVP_MAX_MD_SIZE
];
477 unsigned char *hash
= hashval
;
478 unsigned char *insecret
;
479 unsigned char *finsecret
= NULL
;
480 const char *log_label
= NULL
;
481 EVP_CIPHER_CTX
*ciph_ctx
;
482 size_t finsecretlen
= 0;
483 const unsigned char *label
;
484 size_t labellen
, hashlen
= 0;
486 const EVP_MD
*md
= NULL
;
487 const EVP_CIPHER
*cipher
= NULL
;
489 if (which
& SSL3_CC_READ
) {
490 if (s
->enc_read_ctx
!= NULL
) {
491 EVP_CIPHER_CTX_reset(s
->enc_read_ctx
);
493 s
->enc_read_ctx
= EVP_CIPHER_CTX_new();
494 if (s
->enc_read_ctx
== NULL
) {
495 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
,
496 SSL_F_TLS13_CHANGE_CIPHER_STATE
, ERR_R_MALLOC_FAILURE
);
500 ciph_ctx
= s
->enc_read_ctx
;
503 RECORD_LAYER_reset_read_sequence(&s
->rlayer
);
505 s
->statem
.enc_write_state
= ENC_WRITE_STATE_INVALID
;
506 if (s
->enc_write_ctx
!= NULL
) {
507 EVP_CIPHER_CTX_reset(s
->enc_write_ctx
);
509 s
->enc_write_ctx
= EVP_CIPHER_CTX_new();
510 if (s
->enc_write_ctx
== NULL
) {
511 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
,
512 SSL_F_TLS13_CHANGE_CIPHER_STATE
, ERR_R_MALLOC_FAILURE
);
516 ciph_ctx
= s
->enc_write_ctx
;
519 RECORD_LAYER_reset_write_sequence(&s
->rlayer
);
522 if (((which
& SSL3_CC_CLIENT
) && (which
& SSL3_CC_WRITE
))
523 || ((which
& SSL3_CC_SERVER
) && (which
& SSL3_CC_READ
))) {
524 if (which
& SSL3_CC_EARLY
) {
525 EVP_MD_CTX
*mdctx
= NULL
;
528 unsigned int hashlenui
;
529 const SSL_CIPHER
*sslcipher
= SSL_SESSION_get0_cipher(s
->session
);
531 insecret
= s
->early_secret
;
532 label
= client_early_traffic
;
533 labellen
= sizeof(client_early_traffic
) - 1;
534 log_label
= CLIENT_EARLY_LABEL
;
536 handlen
= BIO_get_mem_data(s
->s3
.handshake_buffer
, &hdata
);
538 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
,
539 SSL_F_TLS13_CHANGE_CIPHER_STATE
,
540 SSL_R_BAD_HANDSHAKE_LENGTH
);
544 if (s
->early_data_state
== SSL_EARLY_DATA_CONNECTING
545 && s
->max_early_data
> 0
546 && s
->session
->ext
.max_early_data
== 0) {
548 * If we are attempting to send early data, and we've decided to
549 * actually do it but max_early_data in s->session is 0 then we
550 * must be using an external PSK.
552 if (!ossl_assert(s
->psksession
!= NULL
553 && s
->max_early_data
==
554 s
->psksession
->ext
.max_early_data
)) {
555 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
,
556 SSL_F_TLS13_CHANGE_CIPHER_STATE
,
557 ERR_R_INTERNAL_ERROR
);
560 sslcipher
= SSL_SESSION_get0_cipher(s
->psksession
);
562 if (sslcipher
== NULL
) {
563 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
,
564 SSL_F_TLS13_CHANGE_CIPHER_STATE
, SSL_R_BAD_PSK
);
569 * We need to calculate the handshake digest using the digest from
570 * the session. We haven't yet selected our ciphersuite so we can't
571 * use ssl_handshake_md().
573 mdctx
= EVP_MD_CTX_new();
575 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
,
576 SSL_F_TLS13_CHANGE_CIPHER_STATE
, ERR_R_MALLOC_FAILURE
);
579 cipher
= EVP_get_cipherbynid(SSL_CIPHER_get_cipher_nid(sslcipher
));
580 md
= ssl_md(sslcipher
->algorithm2
);
581 if (md
== NULL
|| !EVP_DigestInit_ex(mdctx
, md
, NULL
)
582 || !EVP_DigestUpdate(mdctx
, hdata
, handlen
)
583 || !EVP_DigestFinal_ex(mdctx
, hashval
, &hashlenui
)) {
584 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
,
585 SSL_F_TLS13_CHANGE_CIPHER_STATE
, ERR_R_INTERNAL_ERROR
);
586 EVP_MD_CTX_free(mdctx
);
590 EVP_MD_CTX_free(mdctx
);
592 if (!tls13_hkdf_expand(s
, md
, insecret
,
593 early_exporter_master_secret
,
594 sizeof(early_exporter_master_secret
) - 1,
596 s
->early_exporter_master_secret
, hashlen
,
598 SSLfatal(s
, SSL_AD_INTERNAL_ERROR
,
599 SSL_F_TLS13_CHANGE_CIPHER_STATE
, ERR_R_INTERNAL_ERROR
);
603 if (!ssl_log_secret(s
, EARLY_EXPORTER_SECRET_LABEL
,
604 s
->early_exporter_master_secret
, hashlen
)) {
605 /* SSLfatal() already called */
608 } else if (which
& SSL3_CC_HANDSHAKE
) {
609 insecret
= s
->handshake_secret
;
610 finsecret
= s
->client_finished_secret
;
611 finsecretlen
= EVP_MD_size(ssl_handshake_md(s
));
612 label
= client_handshake_traffic
;
613 labellen
= sizeof(client_handshake_traffic
) - 1;
614 log_label
= CLIENT_HANDSHAKE_LABEL
;
616 * The handshake hash used for the server read/client write handshake
617 * traffic secret is the same as the hash for the server
618 * write/client read handshake traffic secret. However, if we
619 * processed early data then we delay changing the server
620 * read/client write cipher state until later, and the handshake
621 * hashes have moved on. Therefore we use the value saved earlier
622 * when we did the server write/client read change cipher state.
624 hash
= s
->handshake_traffic_hash
;
626 insecret
= s
->master_secret
;
627 label
= client_application_traffic
;
628 labellen
= sizeof(client_application_traffic
) - 1;
629 log_label
= CLIENT_APPLICATION_LABEL
;
631 * For this we only use the handshake hashes up until the server
632 * Finished hash. We do not include the client's Finished, which is
633 * what ssl_handshake_hash() would give us. Instead we use the
634 * previously saved value.
636 hash
= s
->server_finished_hash
;
639 /* Early data never applies to client-read/server-write */
640 if (which
& SSL3_CC_HANDSHAKE
) {
641 insecret
= s
->handshake_secret
;
642 finsecret
= s
->server_finished_secret
;
643 finsecretlen
= EVP_MD_size(ssl_handshake_md(s
));
644 label
= server_handshake_traffic
;
645 labellen
= sizeof(server_handshake_traffic
) - 1;
646 log_label
= SERVER_HANDSHAKE_LABEL
;
648 insecret
= s
->master_secret
;
649 label
= server_application_traffic
;
650 labellen
= sizeof(server_application_traffic
) - 1;
651 log_label
= SERVER_APPLICATION_LABEL
;
655 if (!(which
& SSL3_CC_EARLY
)) {
656 md
= ssl_handshake_md(s
);
657 cipher
= s
->s3
.tmp
.new_sym_enc
;
658 if (!ssl3_digest_cached_records(s
, 1)
659 || !ssl_handshake_hash(s
, hashval
, sizeof(hashval
), &hashlen
)) {
660 /* SSLfatal() already called */;
666 * Save the hash of handshakes up to now for use when we calculate the
667 * client application traffic secret
669 if (label
== server_application_traffic
)
670 memcpy(s
->server_finished_hash
, hashval
, hashlen
);
672 if (label
== server_handshake_traffic
)
673 memcpy(s
->handshake_traffic_hash
, hashval
, hashlen
);
675 if (label
== client_application_traffic
) {
677 * We also create the resumption master secret, but this time use the
678 * hash for the whole handshake including the Client Finished
680 if (!tls13_hkdf_expand(s
, ssl_handshake_md(s
), insecret
,
681 resumption_master_secret
,
682 sizeof(resumption_master_secret
) - 1,
683 hashval
, hashlen
, s
->resumption_master_secret
,
685 /* SSLfatal() already called */
690 if (!derive_secret_key_and_iv(s
, which
& SSL3_CC_WRITE
, md
, cipher
,
691 insecret
, hash
, label
, labellen
, secret
, iv
,
693 /* SSLfatal() already called */
697 if (label
== server_application_traffic
) {
698 memcpy(s
->server_app_traffic_secret
, secret
, hashlen
);
699 /* Now we create the exporter master secret */
700 if (!tls13_hkdf_expand(s
, ssl_handshake_md(s
), insecret
,
701 exporter_master_secret
,
702 sizeof(exporter_master_secret
) - 1,
703 hash
, hashlen
, s
->exporter_master_secret
,
705 /* SSLfatal() already called */
709 if (!ssl_log_secret(s
, EXPORTER_SECRET_LABEL
, s
->exporter_master_secret
,
711 /* SSLfatal() already called */
714 } else if (label
== client_application_traffic
)
715 memcpy(s
->client_app_traffic_secret
, secret
, hashlen
);
717 if (!ssl_log_secret(s
, log_label
, secret
, hashlen
)) {
718 /* SSLfatal() already called */
722 if (finsecret
!= NULL
723 && !tls13_derive_finishedkey(s
, ssl_handshake_md(s
), secret
,
724 finsecret
, finsecretlen
)) {
725 /* SSLfatal() already called */
729 if (!s
->server
&& label
== client_early_traffic
)
730 s
->statem
.enc_write_state
= ENC_WRITE_STATE_WRITE_PLAIN_ALERTS
;
732 s
->statem
.enc_write_state
= ENC_WRITE_STATE_VALID
;
735 OPENSSL_cleanse(secret
, sizeof(secret
));
739 int tls13_update_key(SSL
*s
, int sending
)
741 #ifdef CHARSET_EBCDIC
742 static const unsigned char application_traffic
[] = { 0x74, 0x72 ,0x61 ,0x66 ,0x66 ,0x69 ,0x63 ,0x20 ,0x75 ,0x70 ,0x64, 0x00};
744 static const unsigned char application_traffic
[] = "traffic upd";
746 const EVP_MD
*md
= ssl_handshake_md(s
);
747 size_t hashlen
= EVP_MD_size(md
);
748 unsigned char *insecret
, *iv
;
749 unsigned char secret
[EVP_MAX_MD_SIZE
];
750 EVP_CIPHER_CTX
*ciph_ctx
;
753 if (s
->server
== sending
)
754 insecret
= s
->server_app_traffic_secret
;
756 insecret
= s
->client_app_traffic_secret
;
759 s
->statem
.enc_write_state
= ENC_WRITE_STATE_INVALID
;
761 ciph_ctx
= s
->enc_write_ctx
;
762 RECORD_LAYER_reset_write_sequence(&s
->rlayer
);
765 ciph_ctx
= s
->enc_read_ctx
;
766 RECORD_LAYER_reset_read_sequence(&s
->rlayer
);
769 if (!derive_secret_key_and_iv(s
, sending
, ssl_handshake_md(s
),
770 s
->s3
.tmp
.new_sym_enc
, insecret
, NULL
,
772 sizeof(application_traffic
) - 1, secret
, iv
,
774 /* SSLfatal() already called */
778 memcpy(insecret
, secret
, hashlen
);
780 s
->statem
.enc_write_state
= ENC_WRITE_STATE_VALID
;
783 OPENSSL_cleanse(secret
, sizeof(secret
));
787 int tls13_alert_code(int code
)
789 /* There are 2 additional alerts in TLSv1.3 compared to TLSv1.2 */
790 if (code
== SSL_AD_MISSING_EXTENSION
|| code
== SSL_AD_CERTIFICATE_REQUIRED
)
793 return tls1_alert_code(code
);
796 int tls13_export_keying_material(SSL
*s
, unsigned char *out
, size_t olen
,
797 const char *label
, size_t llen
,
798 const unsigned char *context
,
799 size_t contextlen
, int use_context
)
801 unsigned char exportsecret
[EVP_MAX_MD_SIZE
];
802 #ifdef CHARSET_EBCDIC
803 static const unsigned char exporterlabel
[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
805 static const unsigned char exporterlabel
[] = "exporter";
807 unsigned char hash
[EVP_MAX_MD_SIZE
], data
[EVP_MAX_MD_SIZE
];
808 const EVP_MD
*md
= ssl_handshake_md(s
);
809 EVP_MD_CTX
*ctx
= EVP_MD_CTX_new();
810 unsigned int hashsize
, datalen
;
813 if (ctx
== NULL
|| !ossl_statem_export_allowed(s
))
819 if (EVP_DigestInit_ex(ctx
, md
, NULL
) <= 0
820 || EVP_DigestUpdate(ctx
, context
, contextlen
) <= 0
821 || EVP_DigestFinal_ex(ctx
, hash
, &hashsize
) <= 0
822 || EVP_DigestInit_ex(ctx
, md
, NULL
) <= 0
823 || EVP_DigestFinal_ex(ctx
, data
, &datalen
) <= 0
824 || !tls13_hkdf_expand(s
, md
, s
->exporter_master_secret
,
825 (const unsigned char *)label
, llen
,
826 data
, datalen
, exportsecret
, hashsize
, 0)
827 || !tls13_hkdf_expand(s
, md
, exportsecret
, exporterlabel
,
828 sizeof(exporterlabel
) - 1, hash
, hashsize
,
834 EVP_MD_CTX_free(ctx
);
838 int tls13_export_keying_material_early(SSL
*s
, unsigned char *out
, size_t olen
,
839 const char *label
, size_t llen
,
840 const unsigned char *context
,
843 #ifdef CHARSET_EBCDIC
844 static const unsigned char exporterlabel
[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
846 static const unsigned char exporterlabel
[] = "exporter";
848 unsigned char exportsecret
[EVP_MAX_MD_SIZE
];
849 unsigned char hash
[EVP_MAX_MD_SIZE
], data
[EVP_MAX_MD_SIZE
];
851 EVP_MD_CTX
*ctx
= EVP_MD_CTX_new();
852 unsigned int hashsize
, datalen
;
854 const SSL_CIPHER
*sslcipher
;
856 if (ctx
== NULL
|| !ossl_statem_export_early_allowed(s
))
859 if (!s
->server
&& s
->max_early_data
> 0
860 && s
->session
->ext
.max_early_data
== 0)
861 sslcipher
= SSL_SESSION_get0_cipher(s
->psksession
);
863 sslcipher
= SSL_SESSION_get0_cipher(s
->session
);
865 md
= ssl_md(sslcipher
->algorithm2
);
868 * Calculate the hash value and store it in |data|. The reason why
869 * the empty string is used is that the definition of TLS-Exporter
872 * TLS-Exporter(label, context_value, key_length) =
873 * HKDF-Expand-Label(Derive-Secret(Secret, label, ""),
874 * "exporter", Hash(context_value), key_length)
876 * Derive-Secret(Secret, Label, Messages) =
877 * HKDF-Expand-Label(Secret, Label,
878 * Transcript-Hash(Messages), Hash.length)
880 * Here Transcript-Hash is the cipher suite hash algorithm.
882 if (EVP_DigestInit_ex(ctx
, md
, NULL
) <= 0
883 || EVP_DigestUpdate(ctx
, context
, contextlen
) <= 0
884 || EVP_DigestFinal_ex(ctx
, hash
, &hashsize
) <= 0
885 || EVP_DigestInit_ex(ctx
, md
, NULL
) <= 0
886 || EVP_DigestFinal_ex(ctx
, data
, &datalen
) <= 0
887 || !tls13_hkdf_expand(s
, md
, s
->early_exporter_master_secret
,
888 (const unsigned char *)label
, llen
,
889 data
, datalen
, exportsecret
, hashsize
, 0)
890 || !tls13_hkdf_expand(s
, md
, exportsecret
, exporterlabel
,
891 sizeof(exporterlabel
) - 1, hash
, hashsize
,
897 EVP_MD_CTX_free(ctx
);