test/handshake_helper.c

   1 /*
   2  * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (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 <string.h>
  11
  12 #include <openssl/bio.h>
  13 #include <openssl/x509_vfy.h>
  14 #include <openssl/ssl.h>
  15
  16 #include "handshake_helper.h"
  17 #include "testutil.h"
  18
  19 HANDSHAKE_RESULT *HANDSHAKE_RESULT_new()
  20 {
  21     HANDSHAKE_RESULT *ret = OPENSSL_zalloc(sizeof(*ret));
  22     TEST_check(ret != NULL);
  23     return ret;
  24 }
  25
  26 void HANDSHAKE_RESULT_free(HANDSHAKE_RESULT *result)
  27 {
  28     if (result == NULL)
  29         return;
  30     OPENSSL_free(result->client_npn_negotiated);
  31     OPENSSL_free(result->server_npn_negotiated);
  32     OPENSSL_free(result->client_alpn_negotiated);
  33     OPENSSL_free(result->server_alpn_negotiated);
  34     OPENSSL_free(result);
  35 }
  36
  37 /*
  38  * Since there appears to be no way to extract the sent/received alert
  39  * from the SSL object directly, we use the info callback and stash
  40  * the result in ex_data.
  41  */
  42 typedef struct handshake_ex_data_st {
  43     int alert_sent;
  44     int num_fatal_alerts_sent;
  45     int alert_received;
  46     int session_ticket_do_not_call;
  47     ssl_servername_t servername;
  48 } HANDSHAKE_EX_DATA;
  49
  50 typedef struct ctx_data_st {
  51     unsigned char *npn_protocols;
  52     size_t npn_protocols_len;
  53     unsigned char *alpn_protocols;
  54     size_t alpn_protocols_len;
  55 } CTX_DATA;
  56
  57 /* |ctx_data| itself is stack-allocated. */
  58 static void ctx_data_free_data(CTX_DATA *ctx_data)
  59 {
  60     OPENSSL_free(ctx_data->npn_protocols);
  61     ctx_data->npn_protocols = NULL;
  62     OPENSSL_free(ctx_data->alpn_protocols);
  63     ctx_data->alpn_protocols = NULL;
  64 }
  65
  66 static int ex_data_idx;
  67
  68 static void info_cb(const SSL *s, int where, int ret)
  69 {
  70     if (where & SSL_CB_ALERT) {
  71         HANDSHAKE_EX_DATA *ex_data =
  72             (HANDSHAKE_EX_DATA*)(SSL_get_ex_data(s, ex_data_idx));
  73         if (where & SSL_CB_WRITE) {
  74             ex_data->alert_sent = ret;
  75             if (strcmp(SSL_alert_type_string(ret), "F") == 0
  76                 || strcmp(SSL_alert_desc_string(ret), "CN") == 0)
  77                 ex_data->num_fatal_alerts_sent++;
  78         } else {
  79             ex_data->alert_received = ret;
  80         }
  81     }
  82 }
  83
  84 /* Select the appropriate server CTX.
  85  * Returns SSL_TLSEXT_ERR_OK if a match was found.
  86  * If |ignore| is 1, returns SSL_TLSEXT_ERR_NOACK on mismatch.
  87  * Otherwise, returns SSL_TLSEXT_ERR_ALERT_FATAL on mismatch.
  88  * An empty SNI extension also returns SSL_TSLEXT_ERR_NOACK.
  89  */
  90 static int select_server_ctx(SSL *s, void *arg, int ignore)
  91 {
  92     const char *servername = SSL_get_servername(s, TLSEXT_NAMETYPE_host_name);
  93     HANDSHAKE_EX_DATA *ex_data =
  94         (HANDSHAKE_EX_DATA*)(SSL_get_ex_data(s, ex_data_idx));
  95
  96     if (servername == NULL) {
  97         ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;
  98         return SSL_TLSEXT_ERR_NOACK;
  99     }
 100
 101     if (strcmp(servername, "server2") == 0) {
 102         SSL_CTX *new_ctx = (SSL_CTX*)arg;
 103         SSL_set_SSL_CTX(s, new_ctx);
 104         /*
 105          * Copy over all the SSL_CTX options - reasonable behavior
 106          * allows testing of cases where the options between two
 107          * contexts differ/conflict
 108          */
 109         SSL_clear_options(s, 0xFFFFFFFFL);
 110         SSL_set_options(s, SSL_CTX_get_options(new_ctx));
 111
 112         ex_data->servername = SSL_TEST_SERVERNAME_SERVER2;
 113         return SSL_TLSEXT_ERR_OK;
 114     } else if (strcmp(servername, "server1") == 0) {
 115         ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;
 116         return SSL_TLSEXT_ERR_OK;
 117     } else if (ignore) {
 118         ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;
 119         return SSL_TLSEXT_ERR_NOACK;
 120     } else {
 121         /* Don't set an explicit alert, to test library defaults. */
 122         return SSL_TLSEXT_ERR_ALERT_FATAL;
 123     }
 124 }
 125
 126 /*
 127  * (RFC 6066):
 128  *  If the server understood the ClientHello extension but
 129  *  does not recognize the server name, the server SHOULD take one of two
 130  *  actions: either abort the handshake by sending a fatal-level
 131  *  unrecognized_name(112) alert or continue the handshake.
 132  *
 133  * This behaviour is up to the application to configure; we test both
 134  * configurations to ensure the state machine propagates the result
 135  * correctly.
 136  */
 137 static int servername_ignore_cb(SSL *s, int *ad, void *arg)
 138 {
 139     return select_server_ctx(s, arg, 1);
 140 }
 141
 142 static int servername_reject_cb(SSL *s, int *ad, void *arg)
 143 {
 144     return select_server_ctx(s, arg, 0);
 145 }
 146
 147 static unsigned char dummy_ocsp_resp_good_val = 0xff;
 148 static unsigned char dummy_ocsp_resp_bad_val = 0xfe;
 149
 150 static int server_ocsp_cb(SSL *s, void *arg)
 151 {
 152     unsigned char *resp;
 153
 154     resp = OPENSSL_malloc(1);
 155     if (resp == NULL)
 156         return SSL_TLSEXT_ERR_ALERT_FATAL;
 157     /*
 158      * For the purposes of testing we just send back a dummy OCSP response
 159      */
 160     *resp = *(unsigned char *)arg;
 161     if (!SSL_set_tlsext_status_ocsp_resp(s, resp, 1))
 162         return SSL_TLSEXT_ERR_ALERT_FATAL;
 163
 164     return SSL_TLSEXT_ERR_OK;
 165 }
 166
 167 static int client_ocsp_cb(SSL *s, void *arg)
 168 {
 169     const unsigned char *resp;
 170     int len;
 171
 172     len = SSL_get_tlsext_status_ocsp_resp(s, &resp);
 173     if (len != 1 || *resp != dummy_ocsp_resp_good_val)
 174         return 0;
 175
 176     return 1;
 177 }
 178
 179 static int verify_reject_cb(X509_STORE_CTX *ctx, void *arg) {
 180     X509_STORE_CTX_set_error(ctx, X509_V_ERR_APPLICATION_VERIFICATION);
 181     return 0;
 182 }
 183
 184 static int verify_accept_cb(X509_STORE_CTX *ctx, void *arg) {
 185     return 1;
 186 }
 187
 188 static int broken_session_ticket_cb(SSL *s, unsigned char *key_name, unsigned char *iv,
 189                                     EVP_CIPHER_CTX *ctx, HMAC_CTX *hctx, int enc)
 190 {
 191     return 0;
 192 }
 193
 194 static int do_not_call_session_ticket_cb(SSL *s, unsigned char *key_name,
 195                                          unsigned char *iv,
 196                                          EVP_CIPHER_CTX *ctx,
 197                                          HMAC_CTX *hctx, int enc)
 198 {
 199     HANDSHAKE_EX_DATA *ex_data =
 200         (HANDSHAKE_EX_DATA*)(SSL_get_ex_data(s, ex_data_idx));
 201     ex_data->session_ticket_do_not_call = 1;
 202     return 0;
 203 }
 204
 205 /* Parse the comma-separated list into TLS format. */
 206 static void parse_protos(const char *protos, unsigned char **out, size_t *outlen)
 207 {
 208     size_t len, i, prefix;
 209
 210     len = strlen(protos);
 211
 212     /* Should never have reuse. */
 213     TEST_check(*out == NULL);
 214
 215     /* Test values are small, so we omit length limit checks. */
 216     *out = OPENSSL_malloc(len + 1);
 217     TEST_check(*out != NULL);
 218     *outlen = len + 1;
 219
 220     /*
 221      * foo => '3', 'f', 'o', 'o'
 222      * foo,bar => '3', 'f', 'o', 'o', '3', 'b', 'a', 'r'
 223      */
 224     memcpy(*out + 1, protos, len);
 225
 226     prefix = 0;
 227     i = prefix + 1;
 228     while (i <= len) {
 229         if ((*out)[i] == ',') {
 230             TEST_check(i - 1 - prefix > 0);
 231             (*out)[prefix] = i - 1 - prefix;
 232             prefix = i;
 233         }
 234         i++;
 235     }
 236     TEST_check(len - prefix > 0);
 237     (*out)[prefix] = len - prefix;
 238 }
 239
 240 #ifndef OPENSSL_NO_NEXTPROTONEG
 241 /*
 242  * The client SHOULD select the first protocol advertised by the server that it
 243  * also supports.  In the event that the client doesn't support any of server's
 244  * protocols, or the server doesn't advertise any, it SHOULD select the first
 245  * protocol that it supports.
 246  */
 247 static int client_npn_cb(SSL *s, unsigned char **out, unsigned char *outlen,
 248                          const unsigned char *in, unsigned int inlen,
 249                          void *arg)
 250 {
 251     CTX_DATA *ctx_data = (CTX_DATA*)(arg);
 252     int ret;
 253
 254     ret = SSL_select_next_proto(out, outlen, in, inlen,
 255                                 ctx_data->npn_protocols,
 256                                 ctx_data->npn_protocols_len);
 257     /* Accept both OPENSSL_NPN_NEGOTIATED and OPENSSL_NPN_NO_OVERLAP. */
 258     TEST_check(ret == OPENSSL_NPN_NEGOTIATED || ret == OPENSSL_NPN_NO_OVERLAP);
 259     return SSL_TLSEXT_ERR_OK;
 260 }
 261
 262 static int server_npn_cb(SSL *s, const unsigned char **data,
 263                          unsigned int *len, void *arg)
 264 {
 265     CTX_DATA *ctx_data = (CTX_DATA*)(arg);
 266     *data = ctx_data->npn_protocols;
 267     *len = ctx_data->npn_protocols_len;
 268     return SSL_TLSEXT_ERR_OK;
 269 }
 270 #endif
 271
 272 /*
 273  * The server SHOULD select the most highly preferred protocol that it supports
 274  * and that is also advertised by the client.  In the event that the server
 275  * supports no protocols that the client advertises, then the server SHALL
 276  * respond with a fatal "no_application_protocol" alert.
 277  */
 278 static int server_alpn_cb(SSL *s, const unsigned char **out,
 279                           unsigned char *outlen, const unsigned char *in,
 280                           unsigned int inlen, void *arg)
 281 {
 282     CTX_DATA *ctx_data = (CTX_DATA*)(arg);
 283     int ret;
 284
 285     /* SSL_select_next_proto isn't const-correct... */
 286     unsigned char *tmp_out;
 287
 288     /*
 289      * The result points either to |in| or to |ctx_data->alpn_protocols|.
 290      * The callback is allowed to point to |in| or to a long-lived buffer,
 291      * so we can return directly without storing a copy.
 292      */
 293     ret = SSL_select_next_proto(&tmp_out, outlen,
 294                                 ctx_data->alpn_protocols,
 295                                 ctx_data->alpn_protocols_len, in, inlen);
 296
 297     *out = tmp_out;
 298     /* Unlike NPN, we don't tolerate a mismatch. */
 299     return ret == OPENSSL_NPN_NEGOTIATED ? SSL_TLSEXT_ERR_OK
 300         : SSL_TLSEXT_ERR_NOACK;
 301 }
 302
 303 /*
 304  * Configure callbacks and other properties that can't be set directly
 305  * in the server/client CONF.
 306  */
 307 static void configure_handshake_ctx(SSL_CTX *server_ctx, SSL_CTX *server2_ctx,
 308                                     SSL_CTX *client_ctx,
 309                                     const SSL_TEST_CTX *test,
 310                                     const SSL_TEST_EXTRA_CONF *extra,
 311                                     CTX_DATA *server_ctx_data,
 312                                     CTX_DATA *server2_ctx_data,
 313                                     CTX_DATA *client_ctx_data)
 314 {
 315     unsigned char *ticket_keys;
 316     size_t ticket_key_len;
 317
 318     TEST_check(SSL_CTX_set_max_send_fragment(server_ctx,
 319                                              test->max_fragment_size) == 1);
 320     if (server2_ctx != NULL) {
 321         TEST_check(SSL_CTX_set_max_send_fragment(server2_ctx,
 322                                                  test->max_fragment_size) == 1);
 323     }
 324     TEST_check(SSL_CTX_set_max_send_fragment(client_ctx,
 325                                              test->max_fragment_size) == 1);
 326
 327     switch (extra->client.verify_callback) {
 328     case SSL_TEST_VERIFY_ACCEPT_ALL:
 329         SSL_CTX_set_cert_verify_callback(client_ctx, &verify_accept_cb,
 330                                          NULL);
 331         break;
 332     case SSL_TEST_VERIFY_REJECT_ALL:
 333         SSL_CTX_set_cert_verify_callback(client_ctx, &verify_reject_cb,
 334                                          NULL);
 335         break;
 336     default:
 337         break;
 338     }
 339
 340     /* link the two contexts for SNI purposes */
 341     switch (extra->server.servername_callback) {
 342     case SSL_TEST_SERVERNAME_IGNORE_MISMATCH:
 343         SSL_CTX_set_tlsext_servername_callback(server_ctx, servername_ignore_cb);
 344         SSL_CTX_set_tlsext_servername_arg(server_ctx, server2_ctx);
 345         break;
 346     case SSL_TEST_SERVERNAME_REJECT_MISMATCH:
 347         SSL_CTX_set_tlsext_servername_callback(server_ctx, servername_reject_cb);
 348         SSL_CTX_set_tlsext_servername_arg(server_ctx, server2_ctx);
 349         break;
 350     default:
 351         break;
 352     }
 353
 354     if (extra->server.cert_status != SSL_TEST_CERT_STATUS_NONE) {
 355         SSL_CTX_set_tlsext_status_type(client_ctx, TLSEXT_STATUSTYPE_ocsp);
 356         SSL_CTX_set_tlsext_status_cb(client_ctx, client_ocsp_cb);
 357         SSL_CTX_set_tlsext_status_arg(client_ctx, NULL);
 358         SSL_CTX_set_tlsext_status_cb(server_ctx, server_ocsp_cb);
 359         SSL_CTX_set_tlsext_status_arg(server_ctx,
 360             ((extra->server.cert_status == SSL_TEST_CERT_STATUS_GOOD_RESPONSE)
 361             ? &dummy_ocsp_resp_good_val : &dummy_ocsp_resp_bad_val));
 362     }
 363
 364     /*
 365      * The initial_ctx/session_ctx always handles the encrypt/decrypt of the
 366      * session ticket. This ticket_key callback is assigned to the second
 367      * session (assigned via SNI), and should never be invoked
 368      */
 369     if (server2_ctx != NULL)
 370         SSL_CTX_set_tlsext_ticket_key_cb(server2_ctx,
 371                                          do_not_call_session_ticket_cb);
 372
 373     if (extra->server.broken_session_ticket) {
 374         SSL_CTX_set_tlsext_ticket_key_cb(server_ctx, broken_session_ticket_cb);
 375     }
 376 #ifndef OPENSSL_NO_NEXTPROTONEG
 377     if (extra->server.npn_protocols != NULL) {
 378         parse_protos(extra->server.npn_protocols,
 379                      &server_ctx_data->npn_protocols,
 380                      &server_ctx_data->npn_protocols_len);
 381         SSL_CTX_set_next_protos_advertised_cb(server_ctx, server_npn_cb,
 382                                               server_ctx_data);
 383     }
 384     if (extra->server2.npn_protocols != NULL) {
 385         parse_protos(extra->server2.npn_protocols,
 386                      &server2_ctx_data->npn_protocols,
 387                      &server2_ctx_data->npn_protocols_len);
 388         TEST_check(server2_ctx != NULL);
 389         SSL_CTX_set_next_protos_advertised_cb(server2_ctx, server_npn_cb,
 390                                               server2_ctx_data);
 391     }
 392     if (extra->client.npn_protocols != NULL) {
 393         parse_protos(extra->client.npn_protocols,
 394                      &client_ctx_data->npn_protocols,
 395                      &client_ctx_data->npn_protocols_len);
 396         SSL_CTX_set_next_proto_select_cb(client_ctx, client_npn_cb,
 397                                          client_ctx_data);
 398     }
 399 #endif
 400     if (extra->server.alpn_protocols != NULL) {
 401         parse_protos(extra->server.alpn_protocols,
 402                      &server_ctx_data->alpn_protocols,
 403                      &server_ctx_data->alpn_protocols_len);
 404         SSL_CTX_set_alpn_select_cb(server_ctx, server_alpn_cb, server_ctx_data);
 405     }
 406     if (extra->server2.alpn_protocols != NULL) {
 407         TEST_check(server2_ctx != NULL);
 408         parse_protos(extra->server2.alpn_protocols,
 409                      &server2_ctx_data->alpn_protocols,
 410                      &server2_ctx_data->alpn_protocols_len);
 411         SSL_CTX_set_alpn_select_cb(server2_ctx, server_alpn_cb, server2_ctx_data);
 412     }
 413     if (extra->client.alpn_protocols != NULL) {
 414         unsigned char *alpn_protos = NULL;
 415         size_t alpn_protos_len;
 416         parse_protos(extra->client.alpn_protocols,
 417                      &alpn_protos, &alpn_protos_len);
 418         /* Reversed return value convention... */
 419         TEST_check(SSL_CTX_set_alpn_protos(client_ctx, alpn_protos,
 420                                            alpn_protos_len) == 0);
 421         OPENSSL_free(alpn_protos);
 422     }
 423
 424     /*
 425      * Use fixed session ticket keys so that we can decrypt a ticket created with
 426      * one CTX in another CTX. Don't address server2 for the moment.
 427      */
 428     ticket_key_len = SSL_CTX_set_tlsext_ticket_keys(server_ctx, NULL, 0);
 429     ticket_keys = OPENSSL_zalloc(ticket_key_len);
 430     TEST_check(ticket_keys != NULL);
 431     TEST_check(SSL_CTX_set_tlsext_ticket_keys(server_ctx, ticket_keys,
 432                                               ticket_key_len) == 1);
 433     OPENSSL_free(ticket_keys);
 434
 435     /* The default log list includes EC keys, so CT can't work without EC. */
 436 #if !defined(OPENSSL_NO_CT) && !defined(OPENSSL_NO_EC)
 437     TEST_check(SSL_CTX_set_default_ctlog_list_file(client_ctx));
 438     switch (extra->client.ct_validation) {
 439     case SSL_TEST_CT_VALIDATION_PERMISSIVE:
 440         TEST_check(SSL_CTX_enable_ct(client_ctx, SSL_CT_VALIDATION_PERMISSIVE));
 441         break;
 442     case SSL_TEST_CT_VALIDATION_STRICT:
 443         TEST_check(SSL_CTX_enable_ct(client_ctx, SSL_CT_VALIDATION_STRICT));
 444         break;
 445     case SSL_TEST_CT_VALIDATION_NONE:
 446         break;
 447     }
 448 #endif
 449 }
 450
 451 /* Configure per-SSL callbacks and other properties. */
 452 static void configure_handshake_ssl(SSL *server, SSL *client,
 453                                     const SSL_TEST_EXTRA_CONF *extra)
 454 {
 455     if (extra->client.servername != SSL_TEST_SERVERNAME_NONE)
 456         SSL_set_tlsext_host_name(client,
 457                                  ssl_servername_name(extra->client.servername));
 458 }
 459
 460 /* The status for each connection phase. */
 461 typedef enum {
 462     PEER_SUCCESS,
 463     PEER_RETRY,
 464     PEER_ERROR
 465 } peer_status_t;
 466
 467 /* An SSL object and associated read-write buffers. */
 468 typedef struct peer_st {
 469     SSL *ssl;
 470     /* Buffer lengths are int to match the SSL read/write API. */
 471     unsigned char *write_buf;
 472     int write_buf_len;
 473     unsigned char *read_buf;
 474     int read_buf_len;
 475     int bytes_to_write;
 476     int bytes_to_read;
 477     peer_status_t status;
 478 } PEER;
 479
 480 static void create_peer(PEER *peer, SSL_CTX *ctx)
 481 {
 482     static const int peer_buffer_size = 64 * 1024;
 483
 484     peer->ssl = SSL_new(ctx);
 485     TEST_check(peer->ssl != NULL);
 486     peer->write_buf = OPENSSL_zalloc(peer_buffer_size);
 487     TEST_check(peer->write_buf != NULL);
 488     peer->read_buf = OPENSSL_zalloc(peer_buffer_size);
 489     TEST_check(peer->read_buf != NULL);
 490     peer->write_buf_len = peer->read_buf_len = peer_buffer_size;
 491 }
 492
 493 static void peer_free_data(PEER *peer)
 494 {
 495     SSL_free(peer->ssl);
 496     OPENSSL_free(peer->write_buf);
 497     OPENSSL_free(peer->read_buf);
 498 }
 499
 500 /*
 501  * Note that we could do the handshake transparently under an SSL_write,
 502  * but separating the steps is more helpful for debugging test failures.
 503  */
 504 static void do_handshake_step(PEER *peer)
 505 {
 506     int ret;
 507
 508     TEST_check(peer->status == PEER_RETRY);
 509     ret = SSL_do_handshake(peer->ssl);
 510
 511     if (ret == 1) {
 512         peer->status = PEER_SUCCESS;
 513     } else if (ret == 0) {
 514         peer->status = PEER_ERROR;
 515     } else {
 516         int error = SSL_get_error(peer->ssl, ret);
 517         /* Memory bios should never block with SSL_ERROR_WANT_WRITE. */
 518         if (error != SSL_ERROR_WANT_READ)
 519             peer->status = PEER_ERROR;
 520     }
 521 }
 522
 523 /*-
 524  * Send/receive some application data. The read-write sequence is
 525  * Peer A: (R) W - first read will yield no data
 526  * Peer B:  R  W
 527  * ...
 528  * Peer A:  R  W
 529  * Peer B:  R  W
 530  * Peer A:  R
 531  */
 532 static void do_app_data_step(PEER *peer)
 533 {
 534     int ret = 1, write_bytes;
 535
 536     TEST_check(peer->status == PEER_RETRY);
 537
 538     /* We read everything available... */
 539     while (ret > 0 && peer->bytes_to_read) {
 540         ret = SSL_read(peer->ssl, peer->read_buf, peer->read_buf_len);
 541         if (ret > 0) {
 542             TEST_check(ret <= peer->bytes_to_read);
 543             peer->bytes_to_read -= ret;
 544         } else if (ret == 0) {
 545             peer->status = PEER_ERROR;
 546             return;
 547         } else {
 548             int error = SSL_get_error(peer->ssl, ret);
 549             if (error != SSL_ERROR_WANT_READ) {
 550                 peer->status = PEER_ERROR;
 551                 return;
 552             } /* Else continue with write. */
 553         }
 554     }
 555
 556     /* ... but we only write one write-buffer-full of data. */
 557     write_bytes = peer->bytes_to_write < peer->write_buf_len ? peer->bytes_to_write :
 558         peer->write_buf_len;
 559     if (write_bytes) {
 560         ret = SSL_write(peer->ssl, peer->write_buf, write_bytes);
 561         if (ret > 0) {
 562             /* SSL_write will only succeed with a complete write. */
 563             TEST_check(ret == write_bytes);
 564             peer->bytes_to_write -= ret;
 565         } else {
 566             /*
 567              * We should perhaps check for SSL_ERROR_WANT_READ/WRITE here
 568              * but this doesn't yet occur with current app data sizes.
 569              */
 570             peer->status = PEER_ERROR;
 571             return;
 572         }
 573     }
 574
 575     /*
 576      * We could simply finish when there was nothing to read, and we have
 577      * nothing left to write. But keeping track of the expected number of bytes
 578      * to read gives us somewhat better guarantees that all data sent is in fact
 579      * received.
 580      */
 581     if (!peer->bytes_to_write && !peer->bytes_to_read) {
 582         peer->status = PEER_SUCCESS;
 583     }
 584 }
 585
 586 /*
 587  * RFC 5246 says:
 588  *
 589  * Note that as of TLS 1.1,
 590  *     failure to properly close a connection no longer requires that a
 591  *     session not be resumed.  This is a change from TLS 1.0 to conform
 592  *     with widespread implementation practice.
 593  *
 594  * However,
 595  * (a) OpenSSL requires that a connection be shutdown for all protocol versions.
 596  * (b) We test lower versions, too.
 597  * So we just implement shutdown. We do a full bidirectional shutdown so that we
 598  * can compare sent and received close_notify alerts and get some test coverage
 599  * for SSL_shutdown as a bonus.
 600  */
 601 static void do_shutdown_step(PEER *peer)
 602 {
 603     int ret;
 604
 605     TEST_check(peer->status == PEER_RETRY);
 606     ret = SSL_shutdown(peer->ssl);
 607
 608     if (ret == 1) {
 609         peer->status = PEER_SUCCESS;
 610     } else if (ret < 0) { /* On 0, we retry. */
 611         int error = SSL_get_error(peer->ssl, ret);
 612         /* Memory bios should never block with SSL_ERROR_WANT_WRITE. */
 613         if (error != SSL_ERROR_WANT_READ)
 614             peer->status = PEER_ERROR;
 615     }
 616 }
 617
 618 typedef enum {
 619     HANDSHAKE,
 620     APPLICATION_DATA,
 621     SHUTDOWN,
 622     CONNECTION_DONE
 623 } connect_phase_t;
 624
 625 static connect_phase_t next_phase(connect_phase_t phase)
 626 {
 627     switch (phase) {
 628     case HANDSHAKE:
 629         return APPLICATION_DATA;
 630     case APPLICATION_DATA:
 631         return SHUTDOWN;
 632     case SHUTDOWN:
 633         return CONNECTION_DONE;
 634     default:
 635         TEST_check(0); /* Should never call next_phase when done. */
 636     }
 637 }
 638
 639 static void do_connect_step(PEER *peer, connect_phase_t phase)
 640 {
 641     switch (phase) {
 642     case HANDSHAKE:
 643         do_handshake_step(peer);
 644         break;
 645     case APPLICATION_DATA:
 646         do_app_data_step(peer);
 647         break;
 648     case SHUTDOWN:
 649         do_shutdown_step(peer);
 650         break;
 651     default:
 652         TEST_check(0);
 653     }
 654 }
 655
 656 typedef enum {
 657     /* Both parties succeeded. */
 658     HANDSHAKE_SUCCESS,
 659     /* Client errored. */
 660     CLIENT_ERROR,
 661     /* Server errored. */
 662     SERVER_ERROR,
 663     /* Peers are in inconsistent state. */
 664     INTERNAL_ERROR,
 665     /* One or both peers not done. */
 666     HANDSHAKE_RETRY
 667 } handshake_status_t;
 668
 669 /*
 670  * Determine the handshake outcome.
 671  * last_status: the status of the peer to have acted last.
 672  * previous_status: the status of the peer that didn't act last.
 673  * client_spoke_last: 1 if the client went last.
 674  */
 675 static handshake_status_t handshake_status(peer_status_t last_status,
 676                                            peer_status_t previous_status,
 677                                            int client_spoke_last)
 678 {
 679     switch (last_status) {
 680     case PEER_SUCCESS:
 681         switch (previous_status) {
 682         case PEER_SUCCESS:
 683             /* Both succeeded. */
 684             return HANDSHAKE_SUCCESS;
 685         case PEER_RETRY:
 686             /* Let the first peer finish. */
 687             return HANDSHAKE_RETRY;
 688         case PEER_ERROR:
 689             /*
 690              * Second peer succeeded despite the fact that the first peer
 691              * already errored. This shouldn't happen.
 692              */
 693             return INTERNAL_ERROR;
 694         }
 695
 696     case PEER_RETRY:
 697         if (previous_status == PEER_RETRY) {
 698             /* Neither peer is done. */
 699             return HANDSHAKE_RETRY;
 700         } else {
 701             /*
 702              * Deadlock: second peer is waiting for more input while first
 703              * peer thinks they're done (no more input is coming).
 704              */
 705             return INTERNAL_ERROR;
 706         }
 707     case PEER_ERROR:
 708         switch (previous_status) {
 709         case PEER_SUCCESS:
 710             /*
 711              * First peer succeeded but second peer errored.
 712              * TODO(emilia): we should be able to continue here (with some
 713              * application data?) to ensure the first peer receives the
 714              * alert / close_notify.
 715              * (No tests currently exercise this branch.)
 716              */
 717             return client_spoke_last ? CLIENT_ERROR : SERVER_ERROR;
 718         case PEER_RETRY:
 719             /* We errored; let the peer finish. */
 720             return HANDSHAKE_RETRY;
 721         case PEER_ERROR:
 722             /* Both peers errored. Return the one that errored first. */
 723             return client_spoke_last ? SERVER_ERROR : CLIENT_ERROR;
 724         }
 725     }
 726     /* Control should never reach here. */
 727     return INTERNAL_ERROR;
 728 }
 729
 730 /* Convert unsigned char buf's that shouldn't contain any NUL-bytes to char. */
 731 static char *dup_str(const unsigned char *in, size_t len)
 732 {
 733     char *ret;
 734
 735     if(len == 0)
 736         return NULL;
 737
 738     /* Assert that the string does not contain NUL-bytes. */
 739     TEST_check(OPENSSL_strnlen((const char*)(in), len) == len);
 740     ret = OPENSSL_strndup((const char*)(in), len);
 741     TEST_check(ret != NULL);
 742     return ret;
 743 }
 744
 745 /*
 746  * Note that |extra| points to the correct client/server configuration
 747  * within |test_ctx|. When configuring the handshake, general mode settings
 748  * are taken from |test_ctx|, and client/server-specific settings should be
 749  * taken from |extra|.
 750  *
 751  * The configuration code should never reach into |test_ctx->extra| or
 752  * |test_ctx->resume_extra| directly.
 753  *
 754  * (We could refactor test mode settings into a substructure. This would result
 755  * in cleaner argument passing but would complicate the test configuration
 756  * parsing.)
 757  */
 758 static HANDSHAKE_RESULT *do_handshake_internal(
 759     SSL_CTX *server_ctx, SSL_CTX *server2_ctx, SSL_CTX *client_ctx,
 760     const SSL_TEST_CTX *test_ctx, const SSL_TEST_EXTRA_CONF *extra,
 761     SSL_SESSION *session_in, SSL_SESSION **session_out)
 762 {
 763     PEER server, client;
 764     BIO *client_to_server, *server_to_client;
 765     HANDSHAKE_EX_DATA server_ex_data, client_ex_data;
 766     CTX_DATA client_ctx_data, server_ctx_data, server2_ctx_data;
 767     HANDSHAKE_RESULT *ret = HANDSHAKE_RESULT_new();
 768     int client_turn = 1;
 769     connect_phase_t phase = HANDSHAKE;
 770     handshake_status_t status = HANDSHAKE_RETRY;
 771     const unsigned char* tick = NULL;
 772     size_t tick_len = 0;
 773     SSL_SESSION* sess = NULL;
 774     const unsigned char *proto = NULL;
 775     /* API dictates unsigned int rather than size_t. */
 776     unsigned int proto_len = 0;
 777
 778     memset(&server_ctx_data, 0, sizeof(server_ctx_data));
 779     memset(&server2_ctx_data, 0, sizeof(server2_ctx_data));
 780     memset(&client_ctx_data, 0, sizeof(client_ctx_data));
 781     memset(&server, 0, sizeof(server));
 782     memset(&client, 0, sizeof(client));
 783
 784     configure_handshake_ctx(server_ctx, server2_ctx, client_ctx, test_ctx, extra,
 785                             &server_ctx_data, &server2_ctx_data, &client_ctx_data);
 786
 787     /* Setup SSL and buffers; additional configuration happens below. */
 788     create_peer(&server, server_ctx);
 789     create_peer(&client, client_ctx);
 790
 791     server.bytes_to_write = client.bytes_to_read = test_ctx->app_data_size;
 792     client.bytes_to_write = server.bytes_to_read = test_ctx->app_data_size;
 793
 794     configure_handshake_ssl(server.ssl, client.ssl, extra);
 795     if (session_in != NULL) {
 796         /* In case we're testing resumption without tickets. */
 797         TEST_check(SSL_CTX_add_session(server_ctx, session_in));
 798         TEST_check(SSL_set_session(client.ssl, session_in));
 799     }
 800
 801     memset(&server_ex_data, 0, sizeof(server_ex_data));
 802     memset(&client_ex_data, 0, sizeof(client_ex_data));
 803
 804     ret->result = SSL_TEST_INTERNAL_ERROR;
 805
 806     client_to_server = BIO_new(BIO_s_mem());
 807     server_to_client = BIO_new(BIO_s_mem());
 808
 809     TEST_check(client_to_server != NULL);
 810     TEST_check(server_to_client != NULL);
 811
 812     /* Non-blocking bio. */
 813     BIO_set_nbio(client_to_server, 1);
 814     BIO_set_nbio(server_to_client, 1);
 815
 816     SSL_set_connect_state(client.ssl);
 817     SSL_set_accept_state(server.ssl);
 818
 819     /* The bios are now owned by the SSL object. */
 820     SSL_set_bio(client.ssl, server_to_client, client_to_server);
 821     TEST_check(BIO_up_ref(server_to_client) > 0);
 822     TEST_check(BIO_up_ref(client_to_server) > 0);
 823     SSL_set_bio(server.ssl, client_to_server, server_to_client);
 824
 825     ex_data_idx = SSL_get_ex_new_index(0, "ex data", NULL, NULL, NULL);
 826     TEST_check(ex_data_idx >= 0);
 827
 828     TEST_check(SSL_set_ex_data(server.ssl, ex_data_idx, &server_ex_data) == 1);
 829     TEST_check(SSL_set_ex_data(client.ssl, ex_data_idx, &client_ex_data) == 1);
 830
 831     SSL_set_info_callback(server.ssl, &info_cb);
 832     SSL_set_info_callback(client.ssl, &info_cb);
 833
 834     client.status = server.status = PEER_RETRY;
 835
 836     /*
 837      * Half-duplex handshake loop.
 838      * Client and server speak to each other synchronously in the same process.
 839      * We use non-blocking BIOs, so whenever one peer blocks for read, it
 840      * returns PEER_RETRY to indicate that it's the other peer's turn to write.
 841      * The handshake succeeds once both peers have succeeded. If one peer
 842      * errors out, we also let the other peer retry (and presumably fail).
 843      */
 844     for(;;) {
 845         if (client_turn) {
 846             do_connect_step(&client, phase);
 847             status = handshake_status(client.status, server.status,
 848                                       1 /* client went last */);
 849         } else {
 850             do_connect_step(&server, phase);
 851             status = handshake_status(server.status, client.status,
 852                                       0 /* server went last */);
 853         }
 854
 855         switch (status) {
 856         case HANDSHAKE_SUCCESS:
 857             phase = next_phase(phase);
 858             if (phase == CONNECTION_DONE) {
 859                 ret->result = SSL_TEST_SUCCESS;
 860                 goto err;
 861             } else {
 862                 client.status = server.status = PEER_RETRY;
 863                 /*
 864                  * For now, client starts each phase. Since each phase is
 865                  * started separately, we can later control this more
 866                  * precisely, for example, to test client-initiated and
 867                  * server-initiated shutdown.
 868                  */
 869                 client_turn = 1;
 870                 break;
 871             }
 872         case CLIENT_ERROR:
 873             ret->result = SSL_TEST_CLIENT_FAIL;
 874             goto err;
 875         case SERVER_ERROR:
 876             ret->result = SSL_TEST_SERVER_FAIL;
 877             goto err;
 878         case INTERNAL_ERROR:
 879             ret->result = SSL_TEST_INTERNAL_ERROR;
 880             goto err;
 881         case HANDSHAKE_RETRY:
 882             /* Continue. */
 883             client_turn ^= 1;
 884             break;
 885         }
 886     }
 887  err:
 888     ret->server_alert_sent = server_ex_data.alert_sent;
 889     ret->server_num_fatal_alerts_sent = server_ex_data.num_fatal_alerts_sent;
 890     ret->server_alert_received = client_ex_data.alert_received;
 891     ret->client_alert_sent = client_ex_data.alert_sent;
 892     ret->client_num_fatal_alerts_sent = client_ex_data.num_fatal_alerts_sent;
 893     ret->client_alert_received = server_ex_data.alert_received;
 894     ret->server_protocol = SSL_version(server.ssl);
 895     ret->client_protocol = SSL_version(client.ssl);
 896     ret->servername = server_ex_data.servername;
 897     if ((sess = SSL_get0_session(client.ssl)) != NULL)
 898         SSL_SESSION_get0_ticket(sess, &tick, &tick_len);
 899     if (tick == NULL || tick_len == 0)
 900         ret->session_ticket = SSL_TEST_SESSION_TICKET_NO;
 901     else
 902         ret->session_ticket = SSL_TEST_SESSION_TICKET_YES;
 903     ret->session_ticket_do_not_call = server_ex_data.session_ticket_do_not_call;
 904
 905 #ifndef OPENSSL_NO_NEXTPROTONEG
 906     SSL_get0_next_proto_negotiated(client.ssl, &proto, &proto_len);
 907     ret->client_npn_negotiated = dup_str(proto, proto_len);
 908
 909     SSL_get0_next_proto_negotiated(server.ssl, &proto, &proto_len);
 910     ret->server_npn_negotiated = dup_str(proto, proto_len);
 911 #endif
 912
 913     SSL_get0_alpn_selected(client.ssl, &proto, &proto_len);
 914     ret->client_alpn_negotiated = dup_str(proto, proto_len);
 915
 916     SSL_get0_alpn_selected(server.ssl, &proto, &proto_len);
 917     ret->server_alpn_negotiated = dup_str(proto, proto_len);
 918
 919     ret->client_resumed = SSL_session_reused(client.ssl);
 920     ret->server_resumed = SSL_session_reused(server.ssl);
 921
 922     if (session_out != NULL)
 923         *session_out = SSL_get1_session(client.ssl);
 924
 925     ctx_data_free_data(&server_ctx_data);
 926     ctx_data_free_data(&server2_ctx_data);
 927     ctx_data_free_data(&client_ctx_data);
 928
 929     peer_free_data(&server);
 930     peer_free_data(&client);
 931     return ret;
 932 }
 933
 934 HANDSHAKE_RESULT *do_handshake(SSL_CTX *server_ctx, SSL_CTX *server2_ctx,
 935                                SSL_CTX *client_ctx, SSL_CTX *resume_server_ctx,
 936                                SSL_CTX *resume_client_ctx,
 937                                const SSL_TEST_CTX *test_ctx)
 938 {
 939     HANDSHAKE_RESULT *result;
 940     SSL_SESSION *session = NULL;
 941
 942     result = do_handshake_internal(server_ctx, server2_ctx, client_ctx,
 943                                    test_ctx, &test_ctx->extra,
 944                                    NULL, &session);
 945     if (test_ctx->handshake_mode == SSL_TEST_HANDSHAKE_SIMPLE)
 946         goto end;
 947
 948     TEST_check(test_ctx->handshake_mode == SSL_TEST_HANDSHAKE_RESUME);
 949
 950     if (result->result != SSL_TEST_SUCCESS) {
 951         result->result = SSL_TEST_FIRST_HANDSHAKE_FAILED;
 952         goto end;
 953     }
 954
 955     HANDSHAKE_RESULT_free(result);
 956     /* We don't support SNI on second handshake yet, so server2_ctx is NULL. */
 957     result = do_handshake_internal(resume_server_ctx, NULL, resume_client_ctx,
 958                                    test_ctx, &test_ctx->resume_extra,
 959                                    session, NULL);
 960  end:
 961     SSL_SESSION_free(session);
 962     return result;
 963 }