ba385f6ea2e5d7b64c0064247ff7b69e72e8469f
[openssl.git] / ssl / tls13_enc.c
1 /*
2  * Copyright 2016-2020 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 /* Always filled with zeros */
22 static const unsigned char default_zeros[EVP_MAX_MD_SIZE];
23
24 /*
25  * Given a |secret|; a |label| of length |labellen|; and |data| of length
26  * |datalen| (e.g. typically a hash of the handshake messages), derive a new
27  * secret |outlen| bytes long and store it in the location pointed to be |out|.
28  * The |data| value may be zero length. Any errors will be treated as fatal if
29  * |fatal| is set. Returns 1 on success  0 on failure.
30  */
31 int tls13_hkdf_expand(SSL *s, const EVP_MD *md, const unsigned char *secret,
32                              const unsigned char *label, size_t labellen,
33                              const unsigned char *data, size_t datalen,
34                              unsigned char *out, size_t outlen, int fatal)
35 {
36 #ifdef CHARSET_EBCDIC
37     static const unsigned char label_prefix[] = { 0x74, 0x6C, 0x73, 0x31, 0x33, 0x20, 0x00 };
38 #else
39     static const unsigned char label_prefix[] = "tls13 ";
40 #endif
41     EVP_KDF *kdf = EVP_KDF_fetch(s->ctx->libctx, OSSL_KDF_NAME_HKDF,
42                                  s->ctx->propq);
43     EVP_KDF_CTX *kctx;
44     OSSL_PARAM params[5], *p = params;
45     int mode = EVP_PKEY_HKDEF_MODE_EXPAND_ONLY;
46     const char *mdname = EVP_MD_name(md);
47     int ret;
48     size_t hkdflabellen;
49     size_t hashlen;
50     /*
51      * 2 bytes for length of derived secret + 1 byte for length of combined
52      * prefix and label + bytes for the label itself + 1 byte length of hash
53      * + bytes for the hash itself
54      */
55     unsigned char hkdflabel[sizeof(uint16_t) + sizeof(uint8_t)
56                             + (sizeof(label_prefix) - 1) + TLS13_MAX_LABEL_LEN
57                             + 1 + EVP_MAX_MD_SIZE];
58     WPACKET pkt;
59
60     kctx = EVP_KDF_CTX_new(kdf);
61     EVP_KDF_free(kdf);
62     if (kctx == NULL)
63         return 0;
64
65     if (labellen > TLS13_MAX_LABEL_LEN) {
66         if (fatal) {
67             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_HKDF_EXPAND,
68                      ERR_R_INTERNAL_ERROR);
69         } else {
70             /*
71              * Probably we have been called from SSL_export_keying_material(),
72              * or SSL_export_keying_material_early().
73              */
74             SSLerr(SSL_F_TLS13_HKDF_EXPAND, SSL_R_TLS_ILLEGAL_EXPORTER_LABEL);
75         }
76         EVP_KDF_CTX_free(kctx);
77         return 0;
78     }
79
80     hashlen = EVP_MD_size(md);
81
82     if (!WPACKET_init_static_len(&pkt, hkdflabel, sizeof(hkdflabel), 0)
83             || !WPACKET_put_bytes_u16(&pkt, outlen)
84             || !WPACKET_start_sub_packet_u8(&pkt)
85             || !WPACKET_memcpy(&pkt, label_prefix, sizeof(label_prefix) - 1)
86             || !WPACKET_memcpy(&pkt, label, labellen)
87             || !WPACKET_close(&pkt)
88             || !WPACKET_sub_memcpy_u8(&pkt, data, (data == NULL) ? 0 : datalen)
89             || !WPACKET_get_total_written(&pkt, &hkdflabellen)
90             || !WPACKET_finish(&pkt)) {
91         EVP_KDF_CTX_free(kctx);
92         WPACKET_cleanup(&pkt);
93         if (fatal)
94             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_HKDF_EXPAND,
95                      ERR_R_INTERNAL_ERROR);
96         else
97             SSLerr(SSL_F_TLS13_HKDF_EXPAND, ERR_R_INTERNAL_ERROR);
98         return 0;
99     }
100
101     *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE, &mode);
102     *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
103                                             (char *)mdname, 0);
104     *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY,
105                                              (unsigned char *)secret, hashlen);
106     *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_INFO,
107                                              hkdflabel, hkdflabellen);
108     *p++ = OSSL_PARAM_construct_end();
109
110     ret = EVP_KDF_CTX_set_params(kctx, params) <= 0
111         || EVP_KDF_derive(kctx, out, outlen) <= 0;
112
113     EVP_KDF_CTX_free(kctx);
114
115     if (ret != 0) {
116         if (fatal)
117             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_HKDF_EXPAND,
118                      ERR_R_INTERNAL_ERROR);
119         else
120             SSLerr(SSL_F_TLS13_HKDF_EXPAND, ERR_R_INTERNAL_ERROR);
121     }
122
123     return ret == 0;
124 }
125
126 /*
127  * Given a |secret| generate a |key| of length |keylen| bytes. Returns 1 on
128  * success  0 on failure.
129  */
130 int tls13_derive_key(SSL *s, const EVP_MD *md, const unsigned char *secret,
131                      unsigned char *key, size_t keylen)
132 {
133 #ifdef CHARSET_EBCDIC
134   static const unsigned char keylabel[] ={ 0x6B, 0x65, 0x79, 0x00 };
135 #else
136   static const unsigned char keylabel[] = "key";
137 #endif
138
139     return tls13_hkdf_expand(s, md, secret, keylabel, sizeof(keylabel) - 1,
140                              NULL, 0, key, keylen, 1);
141 }
142
143 /*
144  * Given a |secret| generate an |iv| of length |ivlen| bytes. Returns 1 on
145  * success  0 on failure.
146  */
147 int tls13_derive_iv(SSL *s, const EVP_MD *md, const unsigned char *secret,
148                     unsigned char *iv, size_t ivlen)
149 {
150 #ifdef CHARSET_EBCDIC
151   static const unsigned char ivlabel[] = { 0x69, 0x76, 0x00 };
152 #else
153   static const unsigned char ivlabel[] = "iv";
154 #endif
155
156     return tls13_hkdf_expand(s, md, secret, ivlabel, sizeof(ivlabel) - 1,
157                              NULL, 0, iv, ivlen, 1);
158 }
159
160 int tls13_derive_finishedkey(SSL *s, const EVP_MD *md,
161                              const unsigned char *secret,
162                              unsigned char *fin, size_t finlen)
163 {
164 #ifdef CHARSET_EBCDIC
165   static const unsigned char finishedlabel[] = { 0x66, 0x69, 0x6E, 0x69, 0x73, 0x68, 0x65, 0x64, 0x00 };
166 #else
167   static const unsigned char finishedlabel[] = "finished";
168 #endif
169
170     return tls13_hkdf_expand(s, md, secret, finishedlabel,
171                              sizeof(finishedlabel) - 1, NULL, 0, fin, finlen, 1);
172 }
173
174 /*
175  * Given the previous secret |prevsecret| and a new input secret |insecret| of
176  * length |insecretlen|, generate a new secret and store it in the location
177  * pointed to by |outsecret|. Returns 1 on success  0 on failure.
178  */
179 int tls13_generate_secret(SSL *s, const EVP_MD *md,
180                           const unsigned char *prevsecret,
181                           const unsigned char *insecret,
182                           size_t insecretlen,
183                           unsigned char *outsecret)
184 {
185     size_t mdlen, prevsecretlen;
186     int mdleni;
187     int ret;
188     EVP_KDF *kdf;
189     EVP_KDF_CTX *kctx;
190     OSSL_PARAM params[5], *p = params;
191     int mode = EVP_PKEY_HKDEF_MODE_EXTRACT_ONLY;
192     const char *mdname = EVP_MD_name(md);
193 #ifdef CHARSET_EBCDIC
194     static const char derived_secret_label[] = { 0x64, 0x65, 0x72, 0x69, 0x76, 0x65, 0x64, 0x00 };
195 #else
196     static const char derived_secret_label[] = "derived";
197 #endif
198     unsigned char preextractsec[EVP_MAX_MD_SIZE];
199
200     kdf = EVP_KDF_fetch(s->ctx->libctx, OSSL_KDF_NAME_HKDF, s->ctx->propq);
201     kctx = EVP_KDF_CTX_new(kdf);
202     EVP_KDF_free(kdf);
203     if (kctx == NULL) {
204         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET,
205                  ERR_R_INTERNAL_ERROR);
206         return 0;
207     }
208
209     mdleni = EVP_MD_size(md);
210     /* Ensure cast to size_t is safe */
211     if (!ossl_assert(mdleni >= 0)) {
212         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET,
213                  ERR_R_INTERNAL_ERROR);
214         EVP_KDF_CTX_free(kctx);
215         return 0;
216     }
217     mdlen = (size_t)mdleni;
218
219     if (insecret == NULL) {
220         insecret = default_zeros;
221         insecretlen = mdlen;
222     }
223     if (prevsecret == NULL) {
224         prevsecret = default_zeros;
225         prevsecretlen = 0;
226     } else {
227         EVP_MD_CTX *mctx = EVP_MD_CTX_new();
228         unsigned char hash[EVP_MAX_MD_SIZE];
229
230         /* The pre-extract derive step uses a hash of no messages */
231         if (mctx == NULL
232                 || EVP_DigestInit_ex(mctx, md, NULL) <= 0
233                 || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) {
234             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET,
235                      ERR_R_INTERNAL_ERROR);
236             EVP_MD_CTX_free(mctx);
237             EVP_KDF_CTX_free(kctx);
238             return 0;
239         }
240         EVP_MD_CTX_free(mctx);
241
242         /* Generate the pre-extract secret */
243         if (!tls13_hkdf_expand(s, md, prevsecret,
244                                (unsigned char *)derived_secret_label,
245                                sizeof(derived_secret_label) - 1, hash, mdlen,
246                                preextractsec, mdlen, 1)) {
247             /* SSLfatal() already called */
248             EVP_KDF_CTX_free(kctx);
249             return 0;
250         }
251
252         prevsecret = preextractsec;
253         prevsecretlen = mdlen;
254     }
255
256     *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE, &mode);
257     *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
258                                             (char *)mdname, 0);
259     *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY,
260                                              (unsigned char *)insecret,
261                                              insecretlen);
262     *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT,
263                                              (unsigned char *)prevsecret,
264                                              prevsecretlen);
265     *p++ = OSSL_PARAM_construct_end();
266
267     ret = EVP_KDF_CTX_set_params(kctx, params) <= 0
268         || EVP_KDF_derive(kctx, outsecret, mdlen) <= 0;
269
270     if (ret != 0)
271         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET,
272                  ERR_R_INTERNAL_ERROR);
273
274     EVP_KDF_CTX_free(kctx);
275     if (prevsecret == preextractsec)
276         OPENSSL_cleanse(preextractsec, mdlen);
277     return ret == 0;
278 }
279
280 /*
281  * Given an input secret |insecret| of length |insecretlen| generate the
282  * handshake secret. This requires the early secret to already have been
283  * generated. Returns 1 on success  0 on failure.
284  */
285 int tls13_generate_handshake_secret(SSL *s, const unsigned char *insecret,
286                                 size_t insecretlen)
287 {
288     /* Calls SSLfatal() if required */
289     return tls13_generate_secret(s, ssl_handshake_md(s), s->early_secret,
290                                  insecret, insecretlen,
291                                  (unsigned char *)&s->handshake_secret);
292 }
293
294 /*
295  * Given the handshake secret |prev| of length |prevlen| generate the master
296  * secret and store its length in |*secret_size|. Returns 1 on success  0 on
297  * failure.
298  */
299 int tls13_generate_master_secret(SSL *s, unsigned char *out,
300                                  unsigned char *prev, size_t prevlen,
301                                  size_t *secret_size)
302 {
303     const EVP_MD *md = ssl_handshake_md(s);
304
305     *secret_size = EVP_MD_size(md);
306     /* Calls SSLfatal() if required */
307     return tls13_generate_secret(s, md, prev, NULL, 0, out);
308 }
309
310 /*
311  * Generates the mac for the Finished message. Returns the length of the MAC or
312  * 0 on error.
313  */
314 size_t tls13_final_finish_mac(SSL *s, const char *str, size_t slen,
315                              unsigned char *out)
316 {
317     const char *mdname = EVP_MD_name(ssl_handshake_md(s));
318     EVP_MAC *hmac = EVP_MAC_fetch(s->ctx->libctx, "HMAC", s->ctx->propq);
319     unsigned char hash[EVP_MAX_MD_SIZE];
320     unsigned char finsecret[EVP_MAX_MD_SIZE];
321     size_t hashlen, ret = 0;
322     EVP_MAC_CTX *ctx = NULL;
323     OSSL_PARAM params[4], *p = params;
324
325     if (hmac == NULL) {
326         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_FINAL_FINISH_MAC,
327                  ERR_R_INTERNAL_ERROR);
328         goto err;
329     }
330
331     /* Safe to cast away const here since we're not "getting" any data */
332     *p++ = OSSL_PARAM_construct_utf8_string(OSSL_ALG_PARAM_DIGEST,
333                                             (char *)mdname, 0);
334     if (s->ctx->propq != NULL)
335         *p++ = OSSL_PARAM_construct_utf8_string(OSSL_ALG_PARAM_PROPERTIES,
336                                                 (char *)s->ctx->propq,
337                                                 0);
338
339     if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) {
340         /* SSLfatal() already called */
341         goto err;
342     }
343
344     if (str == s->method->ssl3_enc->server_finished_label) {
345         *p++ = OSSL_PARAM_construct_octet_string(OSSL_MAC_PARAM_KEY,
346                                                  s->server_finished_secret,
347                                                  hashlen);
348     } else if (SSL_IS_FIRST_HANDSHAKE(s)) {
349         *p++ = OSSL_PARAM_construct_octet_string(OSSL_MAC_PARAM_KEY,
350                                                  s->client_finished_secret,
351                                                  hashlen);
352     } else {
353         if (!tls13_derive_finishedkey(s, ssl_handshake_md(s),
354                                       s->client_app_traffic_secret,
355                                       finsecret, hashlen))
356             goto err;
357
358         *p++ = OSSL_PARAM_construct_octet_string(OSSL_MAC_PARAM_KEY, finsecret,
359                                                  hashlen);
360     }
361     *p++ = OSSL_PARAM_construct_end();
362
363     ctx = EVP_MAC_CTX_new(hmac);
364     if (ctx == NULL
365             || !EVP_MAC_CTX_set_params(ctx, params)
366             || !EVP_MAC_init(ctx)
367             || !EVP_MAC_update(ctx, hash, hashlen)
368                /* outsize as per sizeof(peer_finish_md) */
369             || !EVP_MAC_final(ctx, out, &hashlen, EVP_MAX_MD_SIZE * 2)) {
370         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_FINAL_FINISH_MAC,
371                  ERR_R_INTERNAL_ERROR);
372         goto err;
373     }
374
375     ret = hashlen;
376  err:
377     OPENSSL_cleanse(finsecret, sizeof(finsecret));
378     EVP_MAC_CTX_free(ctx);
379     EVP_MAC_free(hmac);
380     return ret;
381 }
382
383 /*
384  * There isn't really a key block in TLSv1.3, but we still need this function
385  * for initialising the cipher and hash. Returns 1 on success or 0 on failure.
386  */
387 int tls13_setup_key_block(SSL *s)
388 {
389     const EVP_CIPHER *c;
390     const EVP_MD *hash;
391
392     s->session->cipher = s->s3.tmp.new_cipher;
393     if (!ssl_cipher_get_evp(s->ctx, s->session, &c, &hash, NULL, NULL, NULL,
394                             0)) {
395         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_SETUP_KEY_BLOCK,
396                  SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
397         return 0;
398     }
399
400     ssl_evp_cipher_free(s->s3.tmp.new_sym_enc);
401     s->s3.tmp.new_sym_enc = c;
402     ssl_evp_md_free(s->s3.tmp.new_hash);
403     s->s3.tmp.new_hash = hash;
404
405     return 1;
406 }
407
408 static int derive_secret_key_and_iv(SSL *s, int sending, const EVP_MD *md,
409                                     const EVP_CIPHER *ciph,
410                                     const unsigned char *insecret,
411                                     const unsigned char *hash,
412                                     const unsigned char *label,
413                                     size_t labellen, unsigned char *secret,
414                                     unsigned char *key, unsigned char *iv,
415                                     EVP_CIPHER_CTX *ciph_ctx)
416 {
417     size_t ivlen, keylen, taglen;
418     int hashleni = EVP_MD_size(md);
419     size_t hashlen;
420
421     /* Ensure cast to size_t is safe */
422     if (!ossl_assert(hashleni >= 0)) {
423         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DERIVE_SECRET_KEY_AND_IV,
424                  ERR_R_EVP_LIB);
425         return 0;
426     }
427     hashlen = (size_t)hashleni;
428
429     if (!tls13_hkdf_expand(s, md, insecret, label, labellen, hash, hashlen,
430                            secret, hashlen, 1)) {
431         /* SSLfatal() already called */
432         return 0;
433     }
434
435     /* TODO(size_t): convert me */
436     keylen = EVP_CIPHER_key_length(ciph);
437     if (EVP_CIPHER_mode(ciph) == EVP_CIPH_CCM_MODE) {
438         uint32_t algenc;
439
440         ivlen = EVP_CCM_TLS_IV_LEN;
441         if (s->s3.tmp.new_cipher != NULL) {
442             algenc = s->s3.tmp.new_cipher->algorithm_enc;
443         } else if (s->session->cipher != NULL) {
444             /* We've not selected a cipher yet - we must be doing early data */
445             algenc = s->session->cipher->algorithm_enc;
446         } else if (s->psksession != NULL && s->psksession->cipher != NULL) {
447             /* We must be doing early data with out-of-band PSK */
448             algenc = s->psksession->cipher->algorithm_enc;
449         } else {
450             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DERIVE_SECRET_KEY_AND_IV,
451                      ERR_R_EVP_LIB);
452             return 0;
453         }
454         if (algenc & (SSL_AES128CCM8 | SSL_AES256CCM8))
455             taglen = EVP_CCM8_TLS_TAG_LEN;
456          else
457             taglen = EVP_CCM_TLS_TAG_LEN;
458     } else {
459         ivlen = EVP_CIPHER_iv_length(ciph);
460         taglen = 0;
461     }
462
463     if (!tls13_derive_key(s, md, secret, key, keylen)
464             || !tls13_derive_iv(s, md, secret, iv, ivlen)) {
465         /* SSLfatal() already called */
466         return 0;
467     }
468
469     if (EVP_CipherInit_ex(ciph_ctx, ciph, NULL, NULL, NULL, sending) <= 0
470         || !EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL)
471         || (taglen != 0 && !EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_TAG,
472                                                 taglen, NULL))
473         || EVP_CipherInit_ex(ciph_ctx, NULL, NULL, key, NULL, -1) <= 0) {
474         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DERIVE_SECRET_KEY_AND_IV,
475                  ERR_R_EVP_LIB);
476         return 0;
477     }
478
479     return 1;
480 }
481
482 int tls13_change_cipher_state(SSL *s, int which)
483 {
484 #ifdef CHARSET_EBCDIC
485   static const unsigned char client_early_traffic[]       = {0x63, 0x20, 0x65, 0x20,       /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
486   static const unsigned char client_handshake_traffic[]   = {0x63, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
487   static const unsigned char client_application_traffic[] = {0x63, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
488   static const unsigned char server_handshake_traffic[]   = {0x73, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
489   static const unsigned char server_application_traffic[] = {0x73, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
490   static const unsigned char exporter_master_secret[] = {0x65, 0x78, 0x70, 0x20,                    /* master*/  0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
491   static const unsigned char resumption_master_secret[] = {0x72, 0x65, 0x73, 0x20,                  /* master*/  0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
492   static const unsigned char early_exporter_master_secret[] = {0x65, 0x20, 0x65, 0x78, 0x70, 0x20,  /* master*/  0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
493 #else
494     static const unsigned char client_early_traffic[] = "c e traffic";
495     static const unsigned char client_handshake_traffic[] = "c hs traffic";
496     static const unsigned char client_application_traffic[] = "c ap traffic";
497     static const unsigned char server_handshake_traffic[] = "s hs traffic";
498     static const unsigned char server_application_traffic[] = "s ap traffic";
499     static const unsigned char exporter_master_secret[] = "exp master";
500     static const unsigned char resumption_master_secret[] = "res master";
501     static const unsigned char early_exporter_master_secret[] = "e exp master";
502 #endif
503     unsigned char *iv;
504     unsigned char key[EVP_MAX_KEY_LENGTH];
505     unsigned char secret[EVP_MAX_MD_SIZE];
506     unsigned char hashval[EVP_MAX_MD_SIZE];
507     unsigned char *hash = hashval;
508     unsigned char *insecret;
509     unsigned char *finsecret = NULL;
510     const char *log_label = NULL;
511     EVP_CIPHER_CTX *ciph_ctx;
512     size_t finsecretlen = 0;
513     const unsigned char *label;
514     size_t labellen, hashlen = 0;
515     int ret = 0;
516     const EVP_MD *md = NULL;
517     const EVP_CIPHER *cipher = NULL;
518 #if !defined(OPENSSL_NO_KTLS) && defined(OPENSSL_KTLS_TLS13)
519 # ifndef __FreeBSD__
520     struct tls_crypto_info_all crypto_info;
521     BIO *bio;
522 # endif
523 #endif
524
525     if (which & SSL3_CC_READ) {
526         if (s->enc_read_ctx != NULL) {
527             EVP_CIPHER_CTX_reset(s->enc_read_ctx);
528         } else {
529             s->enc_read_ctx = EVP_CIPHER_CTX_new();
530             if (s->enc_read_ctx == NULL) {
531                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
532                          SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
533                 goto err;
534             }
535         }
536         ciph_ctx = s->enc_read_ctx;
537         iv = s->read_iv;
538
539         RECORD_LAYER_reset_read_sequence(&s->rlayer);
540     } else {
541         s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
542         if (s->enc_write_ctx != NULL) {
543             EVP_CIPHER_CTX_reset(s->enc_write_ctx);
544         } else {
545             s->enc_write_ctx = EVP_CIPHER_CTX_new();
546             if (s->enc_write_ctx == NULL) {
547                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
548                          SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
549                 goto err;
550             }
551         }
552         ciph_ctx = s->enc_write_ctx;
553         iv = s->write_iv;
554
555         RECORD_LAYER_reset_write_sequence(&s->rlayer);
556     }
557
558     if (((which & SSL3_CC_CLIENT) && (which & SSL3_CC_WRITE))
559             || ((which & SSL3_CC_SERVER) && (which & SSL3_CC_READ))) {
560         if (which & SSL3_CC_EARLY) {
561             EVP_MD_CTX *mdctx = NULL;
562             long handlen;
563             void *hdata;
564             unsigned int hashlenui;
565             const SSL_CIPHER *sslcipher = SSL_SESSION_get0_cipher(s->session);
566
567             insecret = s->early_secret;
568             label = client_early_traffic;
569             labellen = sizeof(client_early_traffic) - 1;
570             log_label = CLIENT_EARLY_LABEL;
571
572             handlen = BIO_get_mem_data(s->s3.handshake_buffer, &hdata);
573             if (handlen <= 0) {
574                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
575                          SSL_F_TLS13_CHANGE_CIPHER_STATE,
576                          SSL_R_BAD_HANDSHAKE_LENGTH);
577                 goto err;
578             }
579
580             if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
581                     && s->max_early_data > 0
582                     && s->session->ext.max_early_data == 0) {
583                 /*
584                  * If we are attempting to send early data, and we've decided to
585                  * actually do it but max_early_data in s->session is 0 then we
586                  * must be using an external PSK.
587                  */
588                 if (!ossl_assert(s->psksession != NULL
589                         && s->max_early_data ==
590                            s->psksession->ext.max_early_data)) {
591                     SSLfatal(s, SSL_AD_INTERNAL_ERROR,
592                              SSL_F_TLS13_CHANGE_CIPHER_STATE,
593                              ERR_R_INTERNAL_ERROR);
594                     goto err;
595                 }
596                 sslcipher = SSL_SESSION_get0_cipher(s->psksession);
597             }
598             if (sslcipher == NULL) {
599                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
600                          SSL_F_TLS13_CHANGE_CIPHER_STATE, SSL_R_BAD_PSK);
601                 goto err;
602             }
603
604             /*
605              * We need to calculate the handshake digest using the digest from
606              * the session. We haven't yet selected our ciphersuite so we can't
607              * use ssl_handshake_md().
608              */
609             mdctx = EVP_MD_CTX_new();
610             if (mdctx == NULL) {
611                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
612                          SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
613                 goto err;
614             }
615
616             /*
617              * This ups the ref count on cipher so we better make sure we free
618              * it again
619              */
620             if (!ssl_cipher_get_evp_cipher(s->ctx, sslcipher, &cipher)) {
621                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
622                          SSL_F_TLS13_CHANGE_CIPHER_STATE,
623                          SSL_R_ALGORITHM_FETCH_FAILED);
624                 EVP_MD_CTX_free(mdctx);
625                 goto err;
626             }
627
628             md = ssl_md(s->ctx, sslcipher->algorithm2);
629             if (md == NULL || !EVP_DigestInit_ex(mdctx, md, NULL)
630                     || !EVP_DigestUpdate(mdctx, hdata, handlen)
631                     || !EVP_DigestFinal_ex(mdctx, hashval, &hashlenui)) {
632                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
633                          SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
634                 EVP_MD_CTX_free(mdctx);
635                 goto err;
636             }
637             hashlen = hashlenui;
638             EVP_MD_CTX_free(mdctx);
639
640             if (!tls13_hkdf_expand(s, md, insecret,
641                                    early_exporter_master_secret,
642                                    sizeof(early_exporter_master_secret) - 1,
643                                    hashval, hashlen,
644                                    s->early_exporter_master_secret, hashlen,
645                                    1)) {
646                 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
647                          SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
648                 goto err;
649             }
650
651             if (!ssl_log_secret(s, EARLY_EXPORTER_SECRET_LABEL,
652                                 s->early_exporter_master_secret, hashlen)) {
653                 /* SSLfatal() already called */
654                 goto err;
655             }
656         } else if (which & SSL3_CC_HANDSHAKE) {
657             insecret = s->handshake_secret;
658             finsecret = s->client_finished_secret;
659             finsecretlen = EVP_MD_size(ssl_handshake_md(s));
660             label = client_handshake_traffic;
661             labellen = sizeof(client_handshake_traffic) - 1;
662             log_label = CLIENT_HANDSHAKE_LABEL;
663             /*
664              * The handshake hash used for the server read/client write handshake
665              * traffic secret is the same as the hash for the server
666              * write/client read handshake traffic secret. However, if we
667              * processed early data then we delay changing the server
668              * read/client write cipher state until later, and the handshake
669              * hashes have moved on. Therefore we use the value saved earlier
670              * when we did the server write/client read change cipher state.
671              */
672             hash = s->handshake_traffic_hash;
673         } else {
674             insecret = s->master_secret;
675             label = client_application_traffic;
676             labellen = sizeof(client_application_traffic) - 1;
677             log_label = CLIENT_APPLICATION_LABEL;
678             /*
679              * For this we only use the handshake hashes up until the server
680              * Finished hash. We do not include the client's Finished, which is
681              * what ssl_handshake_hash() would give us. Instead we use the
682              * previously saved value.
683              */
684             hash = s->server_finished_hash;
685         }
686     } else {
687         /* Early data never applies to client-read/server-write */
688         if (which & SSL3_CC_HANDSHAKE) {
689             insecret = s->handshake_secret;
690             finsecret = s->server_finished_secret;
691             finsecretlen = EVP_MD_size(ssl_handshake_md(s));
692             label = server_handshake_traffic;
693             labellen = sizeof(server_handshake_traffic) - 1;
694             log_label = SERVER_HANDSHAKE_LABEL;
695         } else {
696             insecret = s->master_secret;
697             label = server_application_traffic;
698             labellen = sizeof(server_application_traffic) - 1;
699             log_label = SERVER_APPLICATION_LABEL;
700         }
701     }
702
703     if (!(which & SSL3_CC_EARLY)) {
704         md = ssl_handshake_md(s);
705         cipher = s->s3.tmp.new_sym_enc;
706         if (!ssl3_digest_cached_records(s, 1)
707                 || !ssl_handshake_hash(s, hashval, sizeof(hashval), &hashlen)) {
708             /* SSLfatal() already called */;
709             goto err;
710         }
711     }
712
713     /*
714      * Save the hash of handshakes up to now for use when we calculate the
715      * client application traffic secret
716      */
717     if (label == server_application_traffic)
718         memcpy(s->server_finished_hash, hashval, hashlen);
719
720     if (label == server_handshake_traffic)
721         memcpy(s->handshake_traffic_hash, hashval, hashlen);
722
723     if (label == client_application_traffic) {
724         /*
725          * We also create the resumption master secret, but this time use the
726          * hash for the whole handshake including the Client Finished
727          */
728         if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
729                                resumption_master_secret,
730                                sizeof(resumption_master_secret) - 1,
731                                hashval, hashlen, s->resumption_master_secret,
732                                hashlen, 1)) {
733             /* SSLfatal() already called */
734             goto err;
735         }
736     }
737
738     /* check whether cipher is known */
739     if(!ossl_assert(cipher != NULL))
740         goto err;
741
742     if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, md, cipher,
743                                   insecret, hash, label, labellen, secret, key,
744                                   iv, ciph_ctx)) {
745         /* SSLfatal() already called */
746         goto err;
747     }
748
749     if (label == server_application_traffic) {
750         memcpy(s->server_app_traffic_secret, secret, hashlen);
751         /* Now we create the exporter master secret */
752         if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
753                                exporter_master_secret,
754                                sizeof(exporter_master_secret) - 1,
755                                hash, hashlen, s->exporter_master_secret,
756                                hashlen, 1)) {
757             /* SSLfatal() already called */
758             goto err;
759         }
760
761         if (!ssl_log_secret(s, EXPORTER_SECRET_LABEL, s->exporter_master_secret,
762                             hashlen)) {
763             /* SSLfatal() already called */
764             goto err;
765         }
766     } else if (label == client_application_traffic)
767         memcpy(s->client_app_traffic_secret, secret, hashlen);
768
769     if (!ssl_log_secret(s, log_label, secret, hashlen)) {
770         /* SSLfatal() already called */
771         goto err;
772     }
773
774     if (finsecret != NULL
775             && !tls13_derive_finishedkey(s, ssl_handshake_md(s), secret,
776                                          finsecret, finsecretlen)) {
777         /* SSLfatal() already called */
778         goto err;
779     }
780
781     if (!s->server && label == client_early_traffic)
782         s->statem.enc_write_state = ENC_WRITE_STATE_WRITE_PLAIN_ALERTS;
783     else
784         s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
785 #ifndef OPENSSL_NO_KTLS
786 # if defined(OPENSSL_KTLS_TLS13)
787 #  ifndef __FreeBSD__
788     if (!(which & SSL3_CC_WRITE) || !(which & SSL3_CC_APPLICATION)
789         || ((which & SSL3_CC_WRITE) && (s->mode & SSL_MODE_NO_KTLS_TX)))
790         goto skip_ktls;
791
792     /* ktls supports only the maximum fragment size */
793     if (ssl_get_max_send_fragment(s) != SSL3_RT_MAX_PLAIN_LENGTH)
794         goto skip_ktls;
795
796     /* ktls does not support record padding */
797     if (s->record_padding_cb != NULL)
798         goto skip_ktls;
799
800     /* check that cipher is supported */
801     if (!ktls_check_supported_cipher(cipher, ciph_ctx))
802         goto skip_ktls;
803
804     bio = s->wbio;
805
806     if (!ossl_assert(bio != NULL)) {
807         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_CHANGE_CIPHER_STATE,
808                  ERR_R_INTERNAL_ERROR);
809         goto err;
810     }
811
812     /* All future data will get encrypted by ktls. Flush the BIO or skip ktls */
813     if (BIO_flush(bio) <= 0)
814         goto skip_ktls;
815
816     /* configure kernel crypto structure */
817     if (!ktls_configure_crypto(cipher, s->version, ciph_ctx, 
818                                RECORD_LAYER_get_write_sequence(&s->rlayer),
819                                &crypto_info, NULL, iv, key))
820         goto skip_ktls;
821
822     /* ktls works with user provided buffers directly */
823     if (BIO_set_ktls(bio, &crypto_info, which & SSL3_CC_WRITE))
824         ssl3_release_write_buffer(s);
825 #  endif
826 skip_ktls:
827 # endif
828 #endif
829     ret = 1;
830  err:
831     if ((which & SSL3_CC_EARLY) != 0) {
832         /* We up-refed this so now we need to down ref */
833         ssl_evp_cipher_free(cipher);
834     }
835     OPENSSL_cleanse(key, sizeof(key));
836     OPENSSL_cleanse(secret, sizeof(secret));
837     return ret;
838 }
839
840 int tls13_update_key(SSL *s, int sending)
841 {
842 #ifdef CHARSET_EBCDIC
843   static const unsigned char application_traffic[] = { 0x74, 0x72 ,0x61 ,0x66 ,0x66 ,0x69 ,0x63 ,0x20 ,0x75 ,0x70 ,0x64, 0x00};
844 #else
845   static const unsigned char application_traffic[] = "traffic upd";
846 #endif
847     const EVP_MD *md = ssl_handshake_md(s);
848     size_t hashlen = EVP_MD_size(md);
849     unsigned char key[EVP_MAX_KEY_LENGTH];
850     unsigned char *insecret, *iv;
851     unsigned char secret[EVP_MAX_MD_SIZE];
852     EVP_CIPHER_CTX *ciph_ctx;
853     int ret = 0;
854
855     if (s->server == sending)
856         insecret = s->server_app_traffic_secret;
857     else
858         insecret = s->client_app_traffic_secret;
859
860     if (sending) {
861         s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
862         iv = s->write_iv;
863         ciph_ctx = s->enc_write_ctx;
864         RECORD_LAYER_reset_write_sequence(&s->rlayer);
865     } else {
866         iv = s->read_iv;
867         ciph_ctx = s->enc_read_ctx;
868         RECORD_LAYER_reset_read_sequence(&s->rlayer);
869     }
870
871     if (!derive_secret_key_and_iv(s, sending, ssl_handshake_md(s),
872                                   s->s3.tmp.new_sym_enc, insecret, NULL,
873                                   application_traffic,
874                                   sizeof(application_traffic) - 1, secret, key,
875                                   iv, ciph_ctx)) {
876         /* SSLfatal() already called */
877         goto err;
878     }
879
880     memcpy(insecret, secret, hashlen);
881
882     s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
883     ret = 1;
884  err:
885     OPENSSL_cleanse(key, sizeof(key));
886     OPENSSL_cleanse(secret, sizeof(secret));
887     return ret;
888 }
889
890 int tls13_alert_code(int code)
891 {
892     /* There are 2 additional alerts in TLSv1.3 compared to TLSv1.2 */
893     if (code == SSL_AD_MISSING_EXTENSION || code == SSL_AD_CERTIFICATE_REQUIRED)
894         return code;
895
896     return tls1_alert_code(code);
897 }
898
899 int tls13_export_keying_material(SSL *s, unsigned char *out, size_t olen,
900                                  const char *label, size_t llen,
901                                  const unsigned char *context,
902                                  size_t contextlen, int use_context)
903 {
904     unsigned char exportsecret[EVP_MAX_MD_SIZE];
905 #ifdef CHARSET_EBCDIC
906     static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
907 #else
908     static const unsigned char exporterlabel[] = "exporter";
909 #endif
910     unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
911     const EVP_MD *md = ssl_handshake_md(s);
912     EVP_MD_CTX *ctx = EVP_MD_CTX_new();
913     unsigned int hashsize, datalen;
914     int ret = 0;
915
916     if (ctx == NULL || !ossl_statem_export_allowed(s))
917         goto err;
918
919     if (!use_context)
920         contextlen = 0;
921
922     if (EVP_DigestInit_ex(ctx, md, NULL) <= 0
923             || EVP_DigestUpdate(ctx, context, contextlen) <= 0
924             || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
925             || EVP_DigestInit_ex(ctx, md, NULL) <= 0
926             || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
927             || !tls13_hkdf_expand(s, md, s->exporter_master_secret,
928                                   (const unsigned char *)label, llen,
929                                   data, datalen, exportsecret, hashsize, 0)
930             || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
931                                   sizeof(exporterlabel) - 1, hash, hashsize,
932                                   out, olen, 0))
933         goto err;
934
935     ret = 1;
936  err:
937     EVP_MD_CTX_free(ctx);
938     return ret;
939 }
940
941 int tls13_export_keying_material_early(SSL *s, unsigned char *out, size_t olen,
942                                        const char *label, size_t llen,
943                                        const unsigned char *context,
944                                        size_t contextlen)
945 {
946 #ifdef CHARSET_EBCDIC
947   static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
948 #else
949   static const unsigned char exporterlabel[] = "exporter";
950 #endif
951     unsigned char exportsecret[EVP_MAX_MD_SIZE];
952     unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
953     const EVP_MD *md;
954     EVP_MD_CTX *ctx = EVP_MD_CTX_new();
955     unsigned int hashsize, datalen;
956     int ret = 0;
957     const SSL_CIPHER *sslcipher;
958
959     if (ctx == NULL || !ossl_statem_export_early_allowed(s))
960         goto err;
961
962     if (!s->server && s->max_early_data > 0
963             && s->session->ext.max_early_data == 0)
964         sslcipher = SSL_SESSION_get0_cipher(s->psksession);
965     else
966         sslcipher = SSL_SESSION_get0_cipher(s->session);
967
968     md = ssl_md(s->ctx, sslcipher->algorithm2);
969
970     /*
971      * Calculate the hash value and store it in |data|. The reason why
972      * the empty string is used is that the definition of TLS-Exporter
973      * is like so:
974      *
975      * TLS-Exporter(label, context_value, key_length) =
976      *     HKDF-Expand-Label(Derive-Secret(Secret, label, ""),
977      *                       "exporter", Hash(context_value), key_length)
978      *
979      * Derive-Secret(Secret, Label, Messages) =
980      *       HKDF-Expand-Label(Secret, Label,
981      *                         Transcript-Hash(Messages), Hash.length)
982      *
983      * Here Transcript-Hash is the cipher suite hash algorithm.
984      */
985     if (EVP_DigestInit_ex(ctx, md, NULL) <= 0
986             || EVP_DigestUpdate(ctx, context, contextlen) <= 0
987             || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
988             || EVP_DigestInit_ex(ctx, md, NULL) <= 0
989             || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
990             || !tls13_hkdf_expand(s, md, s->early_exporter_master_secret,
991                                   (const unsigned char *)label, llen,
992                                   data, datalen, exportsecret, hashsize, 0)
993             || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
994                                   sizeof(exporterlabel) - 1, hash, hashsize,
995                                   out, olen, 0))
996         goto err;
997
998     ret = 1;
999  err:
1000     EVP_MD_CTX_free(ctx);
1001     return ret;
1002 }