ssl/tls13_enc.c

   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  */
  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  */
 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  */
 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
 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  */
 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  */
 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  */
 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  */
 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  */
 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
 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
 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
 476         RECORD_LAYER_reset_read_sequence(&s->rlayer);
 477     } else {
 478         s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
 479         if (s->enc_write_ctx != NULL) {
 480             EVP_CIPHER_CTX_reset(s->enc_write_ctx);
 481         } else {
 482             s->enc_write_ctx = EVP_CIPHER_CTX_new();
 483             if (s->enc_write_ctx == NULL) {
 484                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
 485                 goto err;
 486             }
 487         }
 488         ciph_ctx = s->enc_write_ctx;
 489         iv = s->write_iv;
 490
 491         RECORD_LAYER_reset_write_sequence(&s->rlayer);
 492     }
 493
 494     if (((which & SSL3_CC_CLIENT) && (which & SSL3_CC_WRITE))
 495             || ((which & SSL3_CC_SERVER) && (which & SSL3_CC_READ))) {
 496         if (which & SSL3_CC_EARLY) {
 497             EVP_MD_CTX *mdctx = NULL;
 498             long handlen;
 499             void *hdata;
 500             unsigned int hashlenui;
 501             const SSL_CIPHER *sslcipher = SSL_SESSION_get0_cipher(s->session);
 502
 503             insecret = s->early_secret;
 504             label = client_early_traffic;
 505             labellen = sizeof(client_early_traffic) - 1;
 506             log_label = CLIENT_EARLY_LABEL;
 507
 508             handlen = BIO_get_mem_data(s->s3.handshake_buffer, &hdata);
 509             if (handlen <= 0) {
 510                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_LENGTH);
 511                 goto err;
 512             }
 513
 514             if (s->early_data_state == SSL_EARLY_DATA_CONNECTING
 515                     && s->max_early_data > 0
 516                     && s->session->ext.max_early_data == 0) {
 517                 /*
 518                  * If we are attempting to send early data, and we've decided to
 519                  * actually do it but max_early_data in s->session is 0 then we
 520                  * must be using an external PSK.
 521                  */
 522                 if (!ossl_assert(s->psksession != NULL
 523                         && s->max_early_data ==
 524                            s->psksession->ext.max_early_data)) {
 525                     SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 526                     goto err;
 527                 }
 528                 sslcipher = SSL_SESSION_get0_cipher(s->psksession);
 529             }
 530             if (sslcipher == NULL) {
 531                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK);
 532                 goto err;
 533             }
 534
 535             /*
 536              * We need to calculate the handshake digest using the digest from
 537              * the session. We haven't yet selected our ciphersuite so we can't
 538              * use ssl_handshake_md().
 539              */
 540             mdctx = EVP_MD_CTX_new();
 541             if (mdctx == NULL) {
 542                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
 543                 goto err;
 544             }
 545
 546             /*
 547              * This ups the ref count on cipher so we better make sure we free
 548              * it again
 549              */
 550             if (!ssl_cipher_get_evp_cipher(sctx, sslcipher, &cipher)) {
 551                 /* Error is already recorded */
 552                 SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);
 553                 EVP_MD_CTX_free(mdctx);
 554                 goto err;
 555             }
 556
 557             md = ssl_md(sctx, sslcipher->algorithm2);
 558             if (md == NULL || !EVP_DigestInit_ex(mdctx, md, NULL)
 559                     || !EVP_DigestUpdate(mdctx, hdata, handlen)
 560                     || !EVP_DigestFinal_ex(mdctx, hashval, &hashlenui)) {
 561                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 562                 EVP_MD_CTX_free(mdctx);
 563                 goto err;
 564             }
 565             hashlen = hashlenui;
 566             EVP_MD_CTX_free(mdctx);
 567
 568             if (!tls13_hkdf_expand(s, md, insecret,
 569                                    early_exporter_master_secret,
 570                                    sizeof(early_exporter_master_secret) - 1,
 571                                    hashval, hashlen,
 572                                    s->early_exporter_master_secret, hashlen,
 573                                    1)) {
 574                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 575                 goto err;
 576             }
 577
 578             if (!ssl_log_secret(s, EARLY_EXPORTER_SECRET_LABEL,
 579                                 s->early_exporter_master_secret, hashlen)) {
 580                 /* SSLfatal() already called */
 581                 goto err;
 582             }
 583         } else if (which & SSL3_CC_HANDSHAKE) {
 584             insecret = s->handshake_secret;
 585             finsecret = s->client_finished_secret;
 586             finsecretlen = EVP_MD_get_size(ssl_handshake_md(s));
 587             label = client_handshake_traffic;
 588             labellen = sizeof(client_handshake_traffic) - 1;
 589             log_label = CLIENT_HANDSHAKE_LABEL;
 590             /*
 591              * The handshake hash used for the server read/client write handshake
 592              * traffic secret is the same as the hash for the server
 593              * write/client read handshake traffic secret. However, if we
 594              * processed early data then we delay changing the server
 595              * read/client write cipher state until later, and the handshake
 596              * hashes have moved on. Therefore we use the value saved earlier
 597              * when we did the server write/client read change cipher state.
 598              */
 599             hash = s->handshake_traffic_hash;
 600         } else {
 601             insecret = s->master_secret;
 602             label = client_application_traffic;
 603             labellen = sizeof(client_application_traffic) - 1;
 604             log_label = CLIENT_APPLICATION_LABEL;
 605             /*
 606              * For this we only use the handshake hashes up until the server
 607              * Finished hash. We do not include the client's Finished, which is
 608              * what ssl_handshake_hash() would give us. Instead we use the
 609              * previously saved value.
 610              */
 611             hash = s->server_finished_hash;
 612         }
 613     } else {
 614         /* Early data never applies to client-read/server-write */
 615         if (which & SSL3_CC_HANDSHAKE) {
 616             insecret = s->handshake_secret;
 617             finsecret = s->server_finished_secret;
 618             finsecretlen = EVP_MD_get_size(ssl_handshake_md(s));
 619             label = server_handshake_traffic;
 620             labellen = sizeof(server_handshake_traffic) - 1;
 621             log_label = SERVER_HANDSHAKE_LABEL;
 622         } else {
 623             insecret = s->master_secret;
 624             label = server_application_traffic;
 625             labellen = sizeof(server_application_traffic) - 1;
 626             log_label = SERVER_APPLICATION_LABEL;
 627         }
 628     }
 629
 630     if (!(which & SSL3_CC_EARLY)) {
 631         md = ssl_handshake_md(s);
 632         cipher = s->s3.tmp.new_sym_enc;
 633         if (!ssl3_digest_cached_records(s, 1)
 634                 || !ssl_handshake_hash(s, hashval, sizeof(hashval), &hashlen)) {
 635             /* SSLfatal() already called */;
 636             goto err;
 637         }
 638     }
 639
 640     /*
 641      * Save the hash of handshakes up to now for use when we calculate the
 642      * client application traffic secret
 643      */
 644     if (label == server_application_traffic)
 645         memcpy(s->server_finished_hash, hashval, hashlen);
 646
 647     if (label == server_handshake_traffic)
 648         memcpy(s->handshake_traffic_hash, hashval, hashlen);
 649
 650     if (label == client_application_traffic) {
 651         /*
 652          * We also create the resumption master secret, but this time use the
 653          * hash for the whole handshake including the Client Finished
 654          */
 655         if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
 656                                resumption_master_secret,
 657                                sizeof(resumption_master_secret) - 1,
 658                                hashval, hashlen, s->resumption_master_secret,
 659                                hashlen, 1)) {
 660             /* SSLfatal() already called */
 661             goto err;
 662         }
 663     }
 664
 665     /* check whether cipher is known */
 666     if (!ossl_assert(cipher != NULL))
 667         goto err;
 668
 669     if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, md, cipher,
 670                                   insecret, hash, label, labellen, secret, key,
 671                                   &keylen, iv, &ivlen, &taglen, ciph_ctx)) {
 672         /* SSLfatal() already called */
 673         goto err;
 674     }
 675
 676     if (label == server_application_traffic) {
 677         memcpy(s->server_app_traffic_secret, secret, hashlen);
 678         /* Now we create the exporter master secret */
 679         if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret,
 680                                exporter_master_secret,
 681                                sizeof(exporter_master_secret) - 1,
 682                                hash, hashlen, s->exporter_master_secret,
 683                                hashlen, 1)) {
 684             /* SSLfatal() already called */
 685             goto err;
 686         }
 687
 688         if (!ssl_log_secret(s, EXPORTER_SECRET_LABEL, s->exporter_master_secret,
 689                             hashlen)) {
 690             /* SSLfatal() already called */
 691             goto err;
 692         }
 693     } else if (label == client_application_traffic)
 694         memcpy(s->client_app_traffic_secret, secret, hashlen);
 695
 696     if (!ssl_log_secret(s, log_label, secret, hashlen)) {
 697         /* SSLfatal() already called */
 698         goto err;
 699     }
 700
 701     if (finsecret != NULL
 702             && !tls13_derive_finishedkey(s, ssl_handshake_md(s), secret,
 703                                          finsecret, finsecretlen)) {
 704         /* SSLfatal() already called */
 705         goto err;
 706     }
 707
 708     if (!s->server && label == client_early_traffic)
 709         s->statem.enc_write_state = ENC_WRITE_STATE_WRITE_PLAIN_ALERTS;
 710     else
 711         s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
 712
 713     if ((which & SSL3_CC_READ) != 0) {
 714         int level = (which & SSL3_CC_EARLY) != 0
 715                     ? OSSL_RECORD_PROTECTION_LEVEL_EARLY
 716                     : ((which &SSL3_CC_HANDSHAKE) != 0
 717                        ? OSSL_RECORD_PROTECTION_LEVEL_HANDSHAKE
 718                        : OSSL_RECORD_PROTECTION_LEVEL_APPLICATION);
 719
 720         if (!ssl_set_new_record_layer(s, s->version,
 721                                     OSSL_RECORD_DIRECTION_READ,
 722                                     level, key, keylen, iv, ivlen, NULL, 0,
 723                                     cipher, taglen, NID_undef, NULL, NULL)) {
 724             /* SSLfatal already called */
 725             goto err;
 726         }
 727         /* TODO(RECLAYER): Remove me when write rlayer done */
 728         goto skip_ktls;
 729     }
 730
 731 #ifndef OPENSSL_NO_KTLS
 732 # if defined(OPENSSL_KTLS_TLS13)
 733     if (!(which & SSL3_CC_APPLICATION)
 734             || (s->options & SSL_OP_ENABLE_KTLS) == 0)
 735         goto skip_ktls;
 736
 737     /* ktls supports only the maximum fragment size */
 738     if (ssl_get_max_send_fragment(s) != SSL3_RT_MAX_PLAIN_LENGTH)
 739         goto skip_ktls;
 740
 741     /* ktls does not support record padding */
 742     if (s->record_padding_cb != NULL)
 743         goto skip_ktls;
 744
 745     /* check that cipher is supported */
 746     if (!ktls_check_supported_cipher(s, cipher, NULL, taglen))
 747         goto skip_ktls;
 748
 749     if (which & SSL3_CC_WRITE)
 750         bio = s->wbio;
 751     else
 752         bio = s->rbio;
 753
 754     if (!ossl_assert(bio != NULL)) {
 755         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
 756         goto err;
 757     }
 758
 759     /* All future data will get encrypted by ktls. Flush the BIO or skip ktls */
 760     if (which & SSL3_CC_WRITE) {
 761         if (BIO_flush(bio) <= 0)
 762             goto skip_ktls;
 763     }
 764
 765     /* configure kernel crypto structure */
 766     if (which & SSL3_CC_WRITE)
 767         rl_sequence = RECORD_LAYER_get_write_sequence(&s->rlayer);
 768     else
 769         rl_sequence = RECORD_LAYER_get_read_sequence(&s->rlayer);
 770
 771     if (!ktls_configure_crypto(sctx->libctx, s->version, cipher, NULL,
 772                                rl_sequence, &crypto_info, which & SSL3_CC_WRITE,
 773                                iv, ivlen, key, keylen, NULL, 0))
 774         goto skip_ktls;
 775
 776     /* ktls works with user provided buffers directly */
 777     if (BIO_set_ktls(bio, &crypto_info, which & SSL3_CC_WRITE)) {
 778         if (which & SSL3_CC_WRITE)
 779             ssl3_release_write_buffer(s);
 780     }
 781 # endif
 782 #endif
 783 skip_ktls:
 784     ret = 1;
 785  err:
 786     if ((which & SSL3_CC_EARLY) != 0) {
 787         /* We up-refed this so now we need to down ref */
 788         ssl_evp_cipher_free(cipher);
 789     }
 790     OPENSSL_cleanse(key, sizeof(key));
 791     OPENSSL_cleanse(secret, sizeof(secret));
 792     return ret;
 793 }
 794
 795 int tls13_update_key(SSL_CONNECTION *s, int sending)
 796 {
 797 #ifdef CHARSET_EBCDIC
 798   static const unsigned char application_traffic[] = { 0x74, 0x72 ,0x61 ,0x66 ,0x66 ,0x69 ,0x63 ,0x20 ,0x75 ,0x70 ,0x64, 0x00};
 799 #else
 800   static const unsigned char application_traffic[] = "traffic upd";
 801 #endif
 802     const EVP_MD *md = ssl_handshake_md(s);
 803     size_t hashlen = EVP_MD_get_size(md);
 804     unsigned char key[EVP_MAX_KEY_LENGTH];
 805     unsigned char *insecret, *iv;
 806     unsigned char secret[EVP_MAX_MD_SIZE];
 807     EVP_CIPHER_CTX *ciph_ctx;
 808     size_t keylen, ivlen, taglen;
 809     int ret = 0;
 810
 811     if (s->server == sending)
 812         insecret = s->server_app_traffic_secret;
 813     else
 814         insecret = s->client_app_traffic_secret;
 815
 816     if (sending) {
 817         s->statem.enc_write_state = ENC_WRITE_STATE_INVALID;
 818         iv = s->write_iv;
 819         ciph_ctx = s->enc_write_ctx;
 820         RECORD_LAYER_reset_write_sequence(&s->rlayer);
 821     } else {
 822         iv = s->read_iv;
 823         ciph_ctx = s->enc_read_ctx;
 824         RECORD_LAYER_reset_read_sequence(&s->rlayer);
 825     }
 826
 827     if (!derive_secret_key_and_iv(s, sending, md,
 828                                   s->s3.tmp.new_sym_enc, insecret, NULL,
 829                                   application_traffic,
 830                                   sizeof(application_traffic) - 1, secret, key,
 831                                   &keylen, iv, &ivlen, &taglen, ciph_ctx)) {
 832         /* SSLfatal() already called */
 833         goto err;
 834     }
 835
 836     memcpy(insecret, secret, hashlen);
 837
 838     if (!sending) {
 839         if (!ssl_set_new_record_layer(s, s->version,
 840                                 OSSL_RECORD_DIRECTION_READ,
 841                                 OSSL_RECORD_PROTECTION_LEVEL_APPLICATION,
 842                                 key, keylen, iv, ivlen, NULL, 0,
 843                                 s->s3.tmp.new_sym_enc, taglen, NID_undef, NULL,
 844                                 NULL)) {
 845             /* SSLfatal already called */
 846             goto err;
 847         }
 848     }
 849
 850     s->statem.enc_write_state = ENC_WRITE_STATE_VALID;
 851     ret = 1;
 852  err:
 853     OPENSSL_cleanse(key, sizeof(key));
 854     OPENSSL_cleanse(secret, sizeof(secret));
 855     return ret;
 856 }
 857
 858 int tls13_alert_code(int code)
 859 {
 860     /* There are 2 additional alerts in TLSv1.3 compared to TLSv1.2 */
 861     if (code == SSL_AD_MISSING_EXTENSION || code == SSL_AD_CERTIFICATE_REQUIRED)
 862         return code;
 863
 864     return tls1_alert_code(code);
 865 }
 866
 867 int tls13_export_keying_material(SSL_CONNECTION *s,
 868                                  unsigned char *out, size_t olen,
 869                                  const char *label, size_t llen,
 870                                  const unsigned char *context,
 871                                  size_t contextlen, int use_context)
 872 {
 873     unsigned char exportsecret[EVP_MAX_MD_SIZE];
 874 #ifdef CHARSET_EBCDIC
 875     static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
 876 #else
 877     static const unsigned char exporterlabel[] = "exporter";
 878 #endif
 879     unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
 880     const EVP_MD *md = ssl_handshake_md(s);
 881     EVP_MD_CTX *ctx = EVP_MD_CTX_new();
 882     unsigned int hashsize, datalen;
 883     int ret = 0;
 884
 885     if (ctx == NULL || md == NULL || !ossl_statem_export_allowed(s))
 886         goto err;
 887
 888     if (!use_context)
 889         contextlen = 0;
 890
 891     if (EVP_DigestInit_ex(ctx, md, NULL) <= 0
 892             || EVP_DigestUpdate(ctx, context, contextlen) <= 0
 893             || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
 894             || EVP_DigestInit_ex(ctx, md, NULL) <= 0
 895             || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
 896             || !tls13_hkdf_expand(s, md, s->exporter_master_secret,
 897                                   (const unsigned char *)label, llen,
 898                                   data, datalen, exportsecret, hashsize, 0)
 899             || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
 900                                   sizeof(exporterlabel) - 1, hash, hashsize,
 901                                   out, olen, 0))
 902         goto err;
 903
 904     ret = 1;
 905  err:
 906     EVP_MD_CTX_free(ctx);
 907     return ret;
 908 }
 909
 910 int tls13_export_keying_material_early(SSL_CONNECTION *s,
 911                                        unsigned char *out, size_t olen,
 912                                        const char *label, size_t llen,
 913                                        const unsigned char *context,
 914                                        size_t contextlen)
 915 {
 916 #ifdef CHARSET_EBCDIC
 917   static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
 918 #else
 919   static const unsigned char exporterlabel[] = "exporter";
 920 #endif
 921     unsigned char exportsecret[EVP_MAX_MD_SIZE];
 922     unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE];
 923     const EVP_MD *md;
 924     EVP_MD_CTX *ctx = EVP_MD_CTX_new();
 925     unsigned int hashsize, datalen;
 926     int ret = 0;
 927     const SSL_CIPHER *sslcipher;
 928
 929     if (ctx == NULL || !ossl_statem_export_early_allowed(s))
 930         goto err;
 931
 932     if (!s->server && s->max_early_data > 0
 933             && s->session->ext.max_early_data == 0)
 934         sslcipher = SSL_SESSION_get0_cipher(s->psksession);
 935     else
 936         sslcipher = SSL_SESSION_get0_cipher(s->session);
 937
 938     md = ssl_md(SSL_CONNECTION_GET_CTX(s), sslcipher->algorithm2);
 939
 940     /*
 941      * Calculate the hash value and store it in |data|. The reason why
 942      * the empty string is used is that the definition of TLS-Exporter
 943      * is like so:
 944      *
 945      * TLS-Exporter(label, context_value, key_length) =
 946      *     HKDF-Expand-Label(Derive-Secret(Secret, label, ""),
 947      *                       "exporter", Hash(context_value), key_length)
 948      *
 949      * Derive-Secret(Secret, Label, Messages) =
 950      *       HKDF-Expand-Label(Secret, Label,
 951      *                         Transcript-Hash(Messages), Hash.length)
 952      *
 953      * Here Transcript-Hash is the cipher suite hash algorithm.
 954      */
 955     if (md == NULL
 956             || EVP_DigestInit_ex(ctx, md, NULL) <= 0
 957             || EVP_DigestUpdate(ctx, context, contextlen) <= 0
 958             || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0
 959             || EVP_DigestInit_ex(ctx, md, NULL) <= 0
 960             || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0
 961             || !tls13_hkdf_expand(s, md, s->early_exporter_master_secret,
 962                                   (const unsigned char *)label, llen,
 963                                   data, datalen, exportsecret, hashsize, 0)
 964             || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel,
 965                                   sizeof(exporterlabel) - 1, hash, hashsize,
 966                                   out, olen, 0))
 967         goto err;
 968
 969     ret = 1;
 970  err:
 971     EVP_MD_CTX_free(ctx);
 972     return ret;
 973 }