dist/wpa/src/tls/tlsv1_server_write.c

   1 /*
   2  * TLSv1 server - write handshake message
   3  * Copyright (c) 2006-2007, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #include "includes.h"
  16
  17 #include "common.h"
  18 #include "md5.h"
  19 #include "sha1.h"
  20 #include "x509v3.h"
  21 #include "tls.h"
  22 #include "tlsv1_common.h"
  23 #include "tlsv1_record.h"
  24 #include "tlsv1_server.h"
  25 #include "tlsv1_server_i.h"
  26
  27
  28 static size_t tls_server_cert_chain_der_len(struct tlsv1_server *conn)
  29 {
  30         size_t len = 0;
  31         struct x509_certificate *cert;
  32
  33         cert = conn->cred->cert;
  34         while (cert) {
  35                 len += 3 + cert->cert_len;
  36                 if (x509_certificate_self_signed(cert))
  37                         break;
  38                 cert = x509_certificate_get_subject(conn->cred->trusted_certs,
  39                                                     &cert->issuer);
  40         }
  41
  42         return len;
  43 }
  44
  45
  46 static int tls_write_server_hello(struct tlsv1_server *conn,
  47                                   u8 **msgpos, u8 *end)
  48 {
  49         u8 *pos, *rhdr, *hs_start, *hs_length;
  50         struct os_time now;
  51         size_t rlen;
  52
  53         pos = *msgpos;
  54
  55         wpa_printf(MSG_DEBUG, "TLSv1: Send ServerHello");
  56         rhdr = pos;
  57         pos += TLS_RECORD_HEADER_LEN;
  58
  59         os_get_time(&now);
  60         WPA_PUT_BE32(conn->server_random, now.sec);
  61         if (os_get_random(conn->server_random + 4, TLS_RANDOM_LEN - 4)) {
  62                 wpa_printf(MSG_ERROR, "TLSv1: Could not generate "
  63                            "server_random");
  64                 return -1;
  65         }
  66         wpa_hexdump(MSG_MSGDUMP, "TLSv1: server_random",
  67                     conn->server_random, TLS_RANDOM_LEN);
  68
  69         conn->session_id_len = TLS_SESSION_ID_MAX_LEN;
  70         if (os_get_random(conn->session_id, conn->session_id_len)) {
  71                 wpa_printf(MSG_ERROR, "TLSv1: Could not generate "
  72                            "session_id");
  73                 return -1;
  74         }
  75         wpa_hexdump(MSG_MSGDUMP, "TLSv1: session_id",
  76                     conn->session_id, conn->session_id_len);
  77
  78         /* opaque fragment[TLSPlaintext.length] */
  79
  80         /* Handshake */
  81         hs_start = pos;
  82         /* HandshakeType msg_type */
  83         *pos++ = TLS_HANDSHAKE_TYPE_SERVER_HELLO;
  84         /* uint24 length (to be filled) */
  85         hs_length = pos;
  86         pos += 3;
  87         /* body - ServerHello */
  88         /* ProtocolVersion server_version */
  89         WPA_PUT_BE16(pos, TLS_VERSION);
  90         pos += 2;
  91         /* Random random: uint32 gmt_unix_time, opaque random_bytes */
  92         os_memcpy(pos, conn->server_random, TLS_RANDOM_LEN);
  93         pos += TLS_RANDOM_LEN;
  94         /* SessionID session_id */
  95         *pos++ = conn->session_id_len;
  96         os_memcpy(pos, conn->session_id, conn->session_id_len);
  97         pos += conn->session_id_len;
  98         /* CipherSuite cipher_suite */
  99         WPA_PUT_BE16(pos, conn->cipher_suite);
 100         pos += 2;
 101         /* CompressionMethod compression_method */
 102         *pos++ = TLS_COMPRESSION_NULL;
 103
 104         if (conn->session_ticket && conn->session_ticket_cb) {
 105                 int res = conn->session_ticket_cb(
 106                         conn->session_ticket_cb_ctx,
 107                         conn->session_ticket, conn->session_ticket_len,
 108                         conn->client_random, conn->server_random,
 109                         conn->master_secret);
 110                 if (res < 0) {
 111                         wpa_printf(MSG_DEBUG, "TLSv1: SessionTicket callback "
 112                                    "indicated failure");
 113                         tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 114                                            TLS_ALERT_HANDSHAKE_FAILURE);
 115                         return -1;
 116                 }
 117                 conn->use_session_ticket = res;
 118
 119                 if (conn->use_session_ticket) {
 120                         if (tlsv1_server_derive_keys(conn, NULL, 0) < 0) {
 121                                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to "
 122                                            "derive keys");
 123                                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 124                                                    TLS_ALERT_INTERNAL_ERROR);
 125                                 return -1;
 126                         }
 127                 }
 128
 129                 /*
 130                  * RFC 4507 specifies that server would include an empty
 131                  * SessionTicket extension in ServerHello and a
 132                  * NewSessionTicket message after the ServerHello. However,
 133                  * EAP-FAST (RFC 4851), i.e., the only user of SessionTicket
 134                  * extension at the moment, does not use such extensions.
 135                  *
 136                  * TODO: Add support for configuring RFC 4507 behavior and make
 137                  * EAP-FAST disable it.
 138                  */
 139         }
 140
 141         WPA_PUT_BE24(hs_length, pos - hs_length - 3);
 142         tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
 143
 144         if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
 145                               rhdr, end - rhdr, pos - hs_start, &rlen) < 0) {
 146                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to create TLS record");
 147                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 148                                    TLS_ALERT_INTERNAL_ERROR);
 149                 return -1;
 150         }
 151         pos = rhdr + rlen;
 152
 153         *msgpos = pos;
 154
 155         return 0;
 156 }
 157
 158
 159 static int tls_write_server_certificate(struct tlsv1_server *conn,
 160                                         u8 **msgpos, u8 *end)
 161 {
 162         u8 *pos, *rhdr, *hs_start, *hs_length, *cert_start;
 163         size_t rlen;
 164         struct x509_certificate *cert;
 165         const struct tls_cipher_suite *suite;
 166
 167         suite = tls_get_cipher_suite(conn->rl.cipher_suite);
 168         if (suite && suite->key_exchange == TLS_KEY_X_DH_anon) {
 169                 wpa_printf(MSG_DEBUG, "TLSv1: Do not send Certificate when "
 170                            "using anonymous DH");
 171                 return 0;
 172         }
 173
 174         pos = *msgpos;
 175
 176         wpa_printf(MSG_DEBUG, "TLSv1: Send Certificate");
 177         rhdr = pos;
 178         pos += TLS_RECORD_HEADER_LEN;
 179
 180         /* opaque fragment[TLSPlaintext.length] */
 181
 182         /* Handshake */
 183         hs_start = pos;
 184         /* HandshakeType msg_type */
 185         *pos++ = TLS_HANDSHAKE_TYPE_CERTIFICATE;
 186         /* uint24 length (to be filled) */
 187         hs_length = pos;
 188         pos += 3;
 189         /* body - Certificate */
 190         /* uint24 length (to be filled) */
 191         cert_start = pos;
 192         pos += 3;
 193         cert = conn->cred->cert;
 194         while (cert) {
 195                 if (pos + 3 + cert->cert_len > end) {
 196                         wpa_printf(MSG_DEBUG, "TLSv1: Not enough buffer space "
 197                                    "for Certificate (cert_len=%lu left=%lu)",
 198                                    (unsigned long) cert->cert_len,
 199                                    (unsigned long) (end - pos));
 200                         tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 201                                            TLS_ALERT_INTERNAL_ERROR);
 202                         return -1;
 203                 }
 204                 WPA_PUT_BE24(pos, cert->cert_len);
 205                 pos += 3;
 206                 os_memcpy(pos, cert->cert_start, cert->cert_len);
 207                 pos += cert->cert_len;
 208
 209                 if (x509_certificate_self_signed(cert))
 210                         break;
 211                 cert = x509_certificate_get_subject(conn->cred->trusted_certs,
 212                                                     &cert->issuer);
 213         }
 214         if (cert == conn->cred->cert || cert == NULL) {
 215                 /*
 216                  * Server was not configured with all the needed certificates
 217                  * to form a full certificate chain. The client may fail to
 218                  * validate the chain unless it is configured with all the
 219                  * missing CA certificates.
 220                  */
 221                 wpa_printf(MSG_DEBUG, "TLSv1: Full server certificate chain "
 222                            "not configured - validation may fail");
 223         }
 224         WPA_PUT_BE24(cert_start, pos - cert_start - 3);
 225
 226         WPA_PUT_BE24(hs_length, pos - hs_length - 3);
 227
 228         if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
 229                               rhdr, end - rhdr, pos - hs_start, &rlen) < 0) {
 230                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate a record");
 231                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 232                                    TLS_ALERT_INTERNAL_ERROR);
 233                 return -1;
 234         }
 235         pos = rhdr + rlen;
 236
 237         tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
 238
 239         *msgpos = pos;
 240
 241         return 0;
 242 }
 243
 244
 245 static int tls_write_server_key_exchange(struct tlsv1_server *conn,
 246                                          u8 **msgpos, u8 *end)
 247 {
 248         tls_key_exchange keyx;
 249         const struct tls_cipher_suite *suite;
 250 #ifdef EAP_FAST
 251         u8 *pos, *rhdr, *hs_start, *hs_length;
 252         size_t rlen;
 253         u8 *dh_ys;
 254         size_t dh_ys_len;
 255 #endif /* EAP_FAST */
 256
 257         suite = tls_get_cipher_suite(conn->rl.cipher_suite);
 258         if (suite == NULL)
 259                 keyx = TLS_KEY_X_NULL;
 260         else
 261                 keyx = suite->key_exchange;
 262
 263         if (!tls_server_key_exchange_allowed(conn->rl.cipher_suite)) {
 264                 wpa_printf(MSG_DEBUG, "TLSv1: No ServerKeyExchange needed");
 265                 return 0;
 266         }
 267
 268         if (keyx != TLS_KEY_X_DH_anon) {
 269                 /* TODO? */
 270                 wpa_printf(MSG_DEBUG, "TLSv1: ServerKeyExchange not yet "
 271                            "supported with key exchange type %d", keyx);
 272                 return -1;
 273         }
 274
 275 #ifdef EAP_FAST
 276         if (conn->cred == NULL || conn->cred->dh_p == NULL ||
 277             conn->cred->dh_g == NULL) {
 278                 wpa_printf(MSG_DEBUG, "TLSv1: No DH parameters available for "
 279                            "ServerKeyExhcange");
 280                 return -1;
 281         }
 282
 283         os_free(conn->dh_secret);
 284         conn->dh_secret_len = conn->cred->dh_p_len;
 285         conn->dh_secret = os_malloc(conn->dh_secret_len);
 286         if (conn->dh_secret == NULL) {
 287                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to allocate "
 288                            "memory for secret (Diffie-Hellman)");
 289                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 290                                    TLS_ALERT_INTERNAL_ERROR);
 291                 return -1;
 292         }
 293         if (os_get_random(conn->dh_secret, conn->dh_secret_len)) {
 294                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to get random "
 295                            "data for Diffie-Hellman");
 296                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 297                                    TLS_ALERT_INTERNAL_ERROR);
 298                 os_free(conn->dh_secret);
 299                 conn->dh_secret = NULL;
 300                 return -1;
 301         }
 302
 303         if (os_memcmp(conn->dh_secret, conn->cred->dh_p, conn->dh_secret_len) >
 304             0)
 305                 conn->dh_secret[0] = 0; /* make sure secret < p */
 306
 307         pos = conn->dh_secret;
 308         while (pos + 1 < conn->dh_secret + conn->dh_secret_len && *pos == 0)
 309                 pos++;
 310         if (pos != conn->dh_secret) {
 311                 os_memmove(conn->dh_secret, pos,
 312                            conn->dh_secret_len - (pos - conn->dh_secret));
 313                 conn->dh_secret_len -= pos - conn->dh_secret;
 314         }
 315         wpa_hexdump_key(MSG_DEBUG, "TLSv1: DH server's secret value",
 316                         conn->dh_secret, conn->dh_secret_len);
 317
 318         /* Ys = g^secret mod p */
 319         dh_ys_len = conn->cred->dh_p_len;
 320         dh_ys = os_malloc(dh_ys_len);
 321         if (dh_ys == NULL) {
 322                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to allocate memory for "
 323                            "Diffie-Hellman");
 324                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 325                                    TLS_ALERT_INTERNAL_ERROR);
 326                 return -1;
 327         }
 328         if (crypto_mod_exp(conn->cred->dh_g, conn->cred->dh_g_len,
 329                            conn->dh_secret, conn->dh_secret_len,
 330                            conn->cred->dh_p, conn->cred->dh_p_len,
 331                            dh_ys, &dh_ys_len)) {
 332                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 333                                    TLS_ALERT_INTERNAL_ERROR);
 334                 os_free(dh_ys);
 335                 return -1;
 336         }
 337
 338         wpa_hexdump(MSG_DEBUG, "TLSv1: DH Ys (server's public value)",
 339                     dh_ys, dh_ys_len);
 340
 341         /*
 342          * struct {
 343          *    select (KeyExchangeAlgorithm) {
 344          *       case diffie_hellman:
 345          *          ServerDHParams params;
 346          *          Signature signed_params;
 347          *       case rsa:
 348          *          ServerRSAParams params;
 349          *          Signature signed_params;
 350          *    };
 351          * } ServerKeyExchange;
 352          *
 353          * struct {
 354          *    opaque dh_p<1..2^16-1>;
 355          *    opaque dh_g<1..2^16-1>;
 356          *    opaque dh_Ys<1..2^16-1>;
 357          * } ServerDHParams;
 358          */
 359
 360         pos = *msgpos;
 361
 362         wpa_printf(MSG_DEBUG, "TLSv1: Send ServerKeyExchange");
 363         rhdr = pos;
 364         pos += TLS_RECORD_HEADER_LEN;
 365
 366         /* opaque fragment[TLSPlaintext.length] */
 367
 368         /* Handshake */
 369         hs_start = pos;
 370         /* HandshakeType msg_type */
 371         *pos++ = TLS_HANDSHAKE_TYPE_SERVER_KEY_EXCHANGE;
 372         /* uint24 length (to be filled) */
 373         hs_length = pos;
 374         pos += 3;
 375
 376         /* body - ServerDHParams */
 377         /* dh_p */
 378         if (pos + 2 + conn->cred->dh_p_len > end) {
 379                 wpa_printf(MSG_DEBUG, "TLSv1: Not enough buffer space for "
 380                            "dh_p");
 381                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 382                                    TLS_ALERT_INTERNAL_ERROR);
 383                 os_free(dh_ys);
 384                 return -1;
 385         }
 386         WPA_PUT_BE16(pos, conn->cred->dh_p_len);
 387         pos += 2;
 388         os_memcpy(pos, conn->cred->dh_p, conn->cred->dh_p_len);
 389         pos += conn->cred->dh_p_len;
 390
 391         /* dh_g */
 392         if (pos + 2 + conn->cred->dh_g_len > end) {
 393                 wpa_printf(MSG_DEBUG, "TLSv1: Not enough buffer space for "
 394                            "dh_g");
 395                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 396                                    TLS_ALERT_INTERNAL_ERROR);
 397                 os_free(dh_ys);
 398                 return -1;
 399         }
 400         WPA_PUT_BE16(pos, conn->cred->dh_g_len);
 401         pos += 2;
 402         os_memcpy(pos, conn->cred->dh_g, conn->cred->dh_g_len);
 403         pos += conn->cred->dh_g_len;
 404
 405         /* dh_Ys */
 406         if (pos + 2 + dh_ys_len > end) {
 407                 wpa_printf(MSG_DEBUG, "TLSv1: Not enough buffer space for "
 408                            "dh_Ys");
 409                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 410                                    TLS_ALERT_INTERNAL_ERROR);
 411                 os_free(dh_ys);
 412                 return -1;
 413         }
 414         WPA_PUT_BE16(pos, dh_ys_len);
 415         pos += 2;
 416         os_memcpy(pos, dh_ys, dh_ys_len);
 417         pos += dh_ys_len;
 418         os_free(dh_ys);
 419
 420         WPA_PUT_BE24(hs_length, pos - hs_length - 3);
 421
 422         if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
 423                               rhdr, end - rhdr, pos - hs_start, &rlen) < 0) {
 424                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate a record");
 425                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 426                                    TLS_ALERT_INTERNAL_ERROR);
 427                 return -1;
 428         }
 429         pos = rhdr + rlen;
 430
 431         tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
 432
 433         *msgpos = pos;
 434
 435         return 0;
 436 #else /* EAP_FAST */
 437         return -1;
 438 #endif /* EAP_FAST */
 439 }
 440
 441
 442 static int tls_write_server_certificate_request(struct tlsv1_server *conn,
 443                                                 u8 **msgpos, u8 *end)
 444 {
 445         u8 *pos, *rhdr, *hs_start, *hs_length;
 446         size_t rlen;
 447
 448         if (!conn->verify_peer) {
 449                 wpa_printf(MSG_DEBUG, "TLSv1: No CertificateRequest needed");
 450                 return 0;
 451         }
 452
 453         pos = *msgpos;
 454
 455         wpa_printf(MSG_DEBUG, "TLSv1: Send CertificateRequest");
 456         rhdr = pos;
 457         pos += TLS_RECORD_HEADER_LEN;
 458
 459         /* opaque fragment[TLSPlaintext.length] */
 460
 461         /* Handshake */
 462         hs_start = pos;
 463         /* HandshakeType msg_type */
 464         *pos++ = TLS_HANDSHAKE_TYPE_CERTIFICATE_REQUEST;
 465         /* uint24 length (to be filled) */
 466         hs_length = pos;
 467         pos += 3;
 468         /* body - CertificateRequest */
 469
 470         /*
 471          * enum {
 472          *   rsa_sign(1), dss_sign(2), rsa_fixed_dh(3), dss_fixed_dh(4),
 473          *   (255)
 474          * } ClientCertificateType;
 475          * ClientCertificateType certificate_types<1..2^8-1>
 476          */
 477         *pos++ = 1;
 478         *pos++ = 1; /* rsa_sign */
 479
 480         /*
 481          * opaque DistinguishedName<1..2^16-1>
 482          * DistinguishedName certificate_authorities<3..2^16-1>
 483          */
 484         /* TODO: add support for listing DNs for trusted CAs */
 485         WPA_PUT_BE16(pos, 0);
 486         pos += 2;
 487
 488         WPA_PUT_BE24(hs_length, pos - hs_length - 3);
 489
 490         if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
 491                               rhdr, end - rhdr, pos - hs_start, &rlen) < 0) {
 492                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate a record");
 493                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 494                                    TLS_ALERT_INTERNAL_ERROR);
 495                 return -1;
 496         }
 497         pos = rhdr + rlen;
 498
 499         tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
 500
 501         *msgpos = pos;
 502
 503         return 0;
 504 }
 505
 506
 507 static int tls_write_server_hello_done(struct tlsv1_server *conn,
 508                                        u8 **msgpos, u8 *end)
 509 {
 510         u8 *pos, *rhdr, *hs_start, *hs_length;
 511         size_t rlen;
 512
 513         pos = *msgpos;
 514
 515         wpa_printf(MSG_DEBUG, "TLSv1: Send ServerHelloDone");
 516         rhdr = pos;
 517         pos += TLS_RECORD_HEADER_LEN;
 518
 519         /* opaque fragment[TLSPlaintext.length] */
 520
 521         /* Handshake */
 522         hs_start = pos;
 523         /* HandshakeType msg_type */
 524         *pos++ = TLS_HANDSHAKE_TYPE_SERVER_HELLO_DONE;
 525         /* uint24 length (to be filled) */
 526         hs_length = pos;
 527         pos += 3;
 528         /* body - ServerHelloDone (empty) */
 529
 530         WPA_PUT_BE24(hs_length, pos - hs_length - 3);
 531
 532         if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
 533                               rhdr, end - rhdr, pos - hs_start, &rlen) < 0) {
 534                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate a record");
 535                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 536                                    TLS_ALERT_INTERNAL_ERROR);
 537                 return -1;
 538         }
 539         pos = rhdr + rlen;
 540
 541         tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
 542
 543         *msgpos = pos;
 544
 545         return 0;
 546 }
 547
 548
 549 static int tls_write_server_change_cipher_spec(struct tlsv1_server *conn,
 550                                                u8 **msgpos, u8 *end)
 551 {
 552         u8 *pos, *rhdr;
 553         size_t rlen;
 554
 555         pos = *msgpos;
 556
 557         wpa_printf(MSG_DEBUG, "TLSv1: Send ChangeCipherSpec");
 558         rhdr = pos;
 559         pos += TLS_RECORD_HEADER_LEN;
 560         *pos = TLS_CHANGE_CIPHER_SPEC;
 561         if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_CHANGE_CIPHER_SPEC,
 562                               rhdr, end - rhdr, 1, &rlen) < 0) {
 563                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to create a record");
 564                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 565                                    TLS_ALERT_INTERNAL_ERROR);
 566                 return -1;
 567         }
 568
 569         if (tlsv1_record_change_write_cipher(&conn->rl) < 0) {
 570                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to set write cipher for "
 571                            "record layer");
 572                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 573                                    TLS_ALERT_INTERNAL_ERROR);
 574                 return -1;
 575         }
 576
 577         *msgpos = rhdr + rlen;
 578
 579         return 0;
 580 }
 581
 582
 583 static int tls_write_server_finished(struct tlsv1_server *conn,
 584                                      u8 **msgpos, u8 *end)
 585 {
 586         u8 *pos, *rhdr, *hs_start, *hs_length;
 587         size_t rlen, hlen;
 588         u8 verify_data[TLS_VERIFY_DATA_LEN];
 589         u8 hash[MD5_MAC_LEN + SHA1_MAC_LEN];
 590
 591         pos = *msgpos;
 592
 593         wpa_printf(MSG_DEBUG, "TLSv1: Send Finished");
 594
 595         /* Encrypted Handshake Message: Finished */
 596
 597         hlen = MD5_MAC_LEN;
 598         if (conn->verify.md5_server == NULL ||
 599             crypto_hash_finish(conn->verify.md5_server, hash, &hlen) < 0) {
 600                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 601                                    TLS_ALERT_INTERNAL_ERROR);
 602                 conn->verify.md5_server = NULL;
 603                 crypto_hash_finish(conn->verify.sha1_server, NULL, NULL);
 604                 conn->verify.sha1_server = NULL;
 605                 return -1;
 606         }
 607         conn->verify.md5_server = NULL;
 608         hlen = SHA1_MAC_LEN;
 609         if (conn->verify.sha1_server == NULL ||
 610             crypto_hash_finish(conn->verify.sha1_server, hash + MD5_MAC_LEN,
 611                                &hlen) < 0) {
 612                 conn->verify.sha1_server = NULL;
 613                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 614                                    TLS_ALERT_INTERNAL_ERROR);
 615                 return -1;
 616         }
 617         conn->verify.sha1_server = NULL;
 618
 619         if (tls_prf(conn->master_secret, TLS_MASTER_SECRET_LEN,
 620                     "server finished", hash, MD5_MAC_LEN + SHA1_MAC_LEN,
 621                     verify_data, TLS_VERIFY_DATA_LEN)) {
 622                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate verify_data");
 623                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 624                                    TLS_ALERT_INTERNAL_ERROR);
 625                 return -1;
 626         }
 627         wpa_hexdump_key(MSG_DEBUG, "TLSv1: verify_data (server)",
 628                         verify_data, TLS_VERIFY_DATA_LEN);
 629
 630         rhdr = pos;
 631         pos += TLS_RECORD_HEADER_LEN;
 632         /* Handshake */
 633         hs_start = pos;
 634         /* HandshakeType msg_type */
 635         *pos++ = TLS_HANDSHAKE_TYPE_FINISHED;
 636         /* uint24 length (to be filled) */
 637         hs_length = pos;
 638         pos += 3;
 639         os_memcpy(pos, verify_data, TLS_VERIFY_DATA_LEN);
 640         pos += TLS_VERIFY_DATA_LEN;
 641         WPA_PUT_BE24(hs_length, pos - hs_length - 3);
 642         tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
 643
 644         if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
 645                               rhdr, end - rhdr, pos - hs_start, &rlen) < 0) {
 646                 wpa_printf(MSG_DEBUG, "TLSv1: Failed to create a record");
 647                 tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
 648                                    TLS_ALERT_INTERNAL_ERROR);
 649                 return -1;
 650         }
 651
 652         pos = rhdr + rlen;
 653
 654         *msgpos = pos;
 655
 656         return 0;
 657 }
 658
 659
 660 static u8 * tls_send_server_hello(struct tlsv1_server *conn, size_t *out_len)
 661 {
 662         u8 *msg, *end, *pos;
 663         size_t msglen;
 664
 665         *out_len = 0;
 666
 667         msglen = 1000 + tls_server_cert_chain_der_len(conn);
 668
 669         msg = os_malloc(msglen);
 670         if (msg == NULL)
 671                 return NULL;
 672
 673         pos = msg;
 674         end = msg + msglen;
 675
 676         if (tls_write_server_hello(conn, &pos, end) < 0) {
 677                 os_free(msg);
 678                 return NULL;
 679         }
 680
 681         if (conn->use_session_ticket) {
 682                 /* Abbreviated handshake using session ticket; RFC 4507 */
 683                 if (tls_write_server_change_cipher_spec(conn, &pos, end) < 0 ||
 684                     tls_write_server_finished(conn, &pos, end) < 0) {
 685                         os_free(msg);
 686                         return NULL;
 687                 }
 688
 689                 *out_len = pos - msg;
 690
 691                 conn->state = CHANGE_CIPHER_SPEC;
 692
 693                 return msg;
 694         }
 695
 696         /* Full handshake */
 697         if (tls_write_server_certificate(conn, &pos, end) < 0 ||
 698             tls_write_server_key_exchange(conn, &pos, end) < 0 ||
 699             tls_write_server_certificate_request(conn, &pos, end) < 0 ||
 700             tls_write_server_hello_done(conn, &pos, end) < 0) {
 701                 os_free(msg);
 702                 return NULL;
 703         }
 704
 705         *out_len = pos - msg;
 706
 707         conn->state = CLIENT_CERTIFICATE;
 708
 709         return msg;
 710 }
 711
 712
 713 static u8 * tls_send_change_cipher_spec(struct tlsv1_server *conn,
 714                                         size_t *out_len)
 715 {
 716         u8 *msg, *end, *pos;
 717
 718         *out_len = 0;
 719
 720         msg = os_malloc(1000);
 721         if (msg == NULL)
 722                 return NULL;
 723
 724         pos = msg;
 725         end = msg + 1000;
 726
 727         if (tls_write_server_change_cipher_spec(conn, &pos, end) < 0 ||
 728             tls_write_server_finished(conn, &pos, end) < 0) {
 729                 os_free(msg);
 730                 return NULL;
 731         }
 732
 733         *out_len = pos - msg;
 734
 735         wpa_printf(MSG_DEBUG, "TLSv1: Handshake completed successfully");
 736         conn->state = ESTABLISHED;
 737
 738         return msg;
 739 }
 740
 741
 742 u8 * tlsv1_server_handshake_write(struct tlsv1_server *conn, size_t *out_len)
 743 {
 744         switch (conn->state) {
 745         case SERVER_HELLO:
 746                 return tls_send_server_hello(conn, out_len);
 747         case SERVER_CHANGE_CIPHER_SPEC:
 748                 return tls_send_change_cipher_spec(conn, out_len);
 749         default:
 750                 if (conn->state == ESTABLISHED && conn->use_session_ticket) {
 751                         /* Abbreviated handshake was already completed. */
 752                         return NULL;
 753                 }
 754                 wpa_printf(MSG_DEBUG, "TLSv1: Unexpected state %d while "
 755                            "generating reply", conn->state);
 756                 return NULL;
 757         }
 758 }
 759
 760
 761 u8 * tlsv1_server_send_alert(struct tlsv1_server *conn, u8 level,
 762                              u8 description, size_t *out_len)
 763 {
 764         u8 *alert, *pos, *length;
 765
 766         wpa_printf(MSG_DEBUG, "TLSv1: Send Alert(%d:%d)", level, description);
 767         *out_len = 0;
 768
 769         alert = os_malloc(10);
 770         if (alert == NULL)
 771                 return NULL;
 772
 773         pos = alert;
 774
 775         /* TLSPlaintext */
 776         /* ContentType type */
 777         *pos++ = TLS_CONTENT_TYPE_ALERT;
 778         /* ProtocolVersion version */
 779         WPA_PUT_BE16(pos, TLS_VERSION);
 780         pos += 2;
 781         /* uint16 length (to be filled) */
 782         length = pos;
 783         pos += 2;
 784         /* opaque fragment[TLSPlaintext.length] */
 785
 786         /* Alert */
 787         /* AlertLevel level */
 788         *pos++ = level;
 789         /* AlertDescription description */
 790         *pos++ = description;
 791
 792         WPA_PUT_BE16(length, pos - length - 2);
 793         *out_len = pos - alert;
 794
 795         return alert;
 796 }