tests/resume.c

   1 /*
   2  * Copyright (C) 2004, 2005, 2007 Free Software Foundation
   3  *
   4  * Author: Simon Josefsson
   5  *
   6  * This file is part of GNUTLS.
   7  *
   8  * GNUTLS is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * GNUTLS is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with GNUTLS; if not, write to the Free Software Foundation,
  20  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
  21  */
  22
  23 /* Parts copied from GnuTLS example programs. */
  24
  25 #if HAVE_CONFIG_H
  26 # include <config.h>
  27 #endif
  28
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <sys/types.h>
  33 #include <sys/socket.h>
  34 #include <sys/wait.h>
  35 #include <netinet/in.h>
  36 #include <arpa/inet.h>
  37 #include <unistd.h>
  38 #include <gnutls/gnutls.h>
  39
  40 #include "utils.h"
  41
  42 static void wrap_db_init (void);
  43 static void wrap_db_deinit (void);
  44 static int wrap_db_store (void *dbf, gnutls_datum_t key, gnutls_datum_t data);
  45 static gnutls_datum_t wrap_db_fetch (void *dbf, gnutls_datum_t key);
  46 static int wrap_db_delete (void *dbf, gnutls_datum_t key);
  47
  48 #define TLS_SESSION_CACHE 50
  49
  50 /* A very basic TLS client, with anonymous authentication.
  51  */
  52
  53 #define MAX_BUF 1024
  54 #define MSG "Hello TLS"
  55
  56 /* Connects to the peer and returns a socket
  57  * descriptor.
  58  */
  59 int
  60 tcp_connect (void)
  61 {
  62   const char *PORT = "5556";
  63   const char *SERVER = "127.0.0.1";
  64   int err, sd;
  65   struct sockaddr_in sa;
  66
  67   /* connects to server
  68    */
  69   sd = socket (AF_INET, SOCK_STREAM, 0);
  70
  71   memset (&sa, '\0', sizeof (sa));
  72   sa.sin_family = AF_INET;
  73   sa.sin_port = htons (atoi (PORT));
  74   inet_pton (AF_INET, SERVER, &sa.sin_addr);
  75
  76   err = connect (sd, (struct sockaddr *) &sa, sizeof (sa));
  77   if (err < 0)
  78     {
  79       fprintf (stderr, "Connect error\n");
  80       exit (1);
  81     }
  82
  83   return sd;
  84 }
  85
  86 /* closes the given socket descriptor.
  87  */
  88 void
  89 tcp_close (int sd)
  90 {
  91   shutdown (sd, SHUT_RDWR);     /* no more receptions */
  92   close (sd);
  93 }
  94
  95 void
  96 client (void)
  97 {
  98   int ret, sd, ii;
  99   gnutls_session_t session;
 100   char buffer[MAX_BUF + 1];
 101   gnutls_anon_client_credentials_t anoncred;
 102   /* Need to enable anonymous KX specifically. */
 103   const int kx_prio[] = { GNUTLS_KX_ANON_DH, 0 };
 104
 105   /* variables used in session resuming
 106    */
 107   int t;
 108   gnutls_datum session_data;
 109
 110   gnutls_global_init ();
 111
 112   gnutls_anon_allocate_client_credentials (&anoncred);
 113
 114   for (t = 0; t < 2; t++)
 115     {                           /* connect 2 times to the server */
 116
 117       /* connect to the peer
 118        */
 119       sd = tcp_connect ();
 120
 121       /* Initialize TLS session
 122        */
 123       gnutls_init (&session, GNUTLS_CLIENT);
 124
 125       /* Use default priorities */
 126       gnutls_set_default_priority (session);
 127       gnutls_kx_set_priority (session, kx_prio);
 128
 129       /* put the anonymous credentials to the current session
 130        */
 131       gnutls_credentials_set (session, GNUTLS_CRD_ANON, anoncred);
 132
 133       if (t > 0)
 134         {
 135           /* if this is not the first time we connect */
 136           gnutls_session_set_data (session, session_data.data,
 137                                    session_data.size);
 138           gnutls_free (session_data.data);
 139         }
 140
 141       gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) sd);
 142
 143       /* Perform the TLS handshake
 144        */
 145       ret = gnutls_handshake (session);
 146
 147       if (ret < 0)
 148         {
 149           fail ("client: Handshake failed\n");
 150           gnutls_perror (ret);
 151           goto end;
 152         }
 153       else
 154         {
 155           success ("client: Handshake was completed\n");
 156         }
 157
 158       if (t == 0)
 159         {                       /* the first time we connect */
 160           /* get the session data size */
 161           ret = gnutls_session_get_data2 (session, &session_data);
 162           if (ret < 0)
 163             fail ("Getting resume data failed\n");
 164         }
 165       else
 166         {                       /* the second time we connect */
 167
 168           /* check if we actually resumed the previous session */
 169           if (gnutls_session_is_resumed (session) != 0)
 170             {
 171               success ("- Previous session was resumed\n");
 172             }
 173           else
 174             {
 175               success ("*** Previous session was NOT resumed\n");
 176             }
 177         }
 178
 179       gnutls_record_send (session, MSG, strlen (MSG));
 180
 181       ret = gnutls_record_recv (session, buffer, MAX_BUF);
 182       if (ret == 0)
 183         {
 184           success ("client: Peer has closed the TLS connection\n");
 185           goto end;
 186         }
 187       else if (ret < 0)
 188         {
 189           fail ("client: Error: %s\n", gnutls_strerror (ret));
 190           goto end;
 191         }
 192
 193       if (debug)
 194         {
 195           printf ("- Received %d bytes: ", ret);
 196           for (ii = 0; ii < ret; ii++)
 197             {
 198               fputc (buffer[ii], stdout);
 199             }
 200           fputs ("\n", stdout);
 201         }
 202
 203       gnutls_bye (session, GNUTLS_SHUT_RDWR);
 204
 205     end:
 206
 207       tcp_close (sd);
 208
 209       gnutls_deinit (session);
 210     }
 211
 212   gnutls_anon_free_client_credentials (anoncred);
 213 }
 214
 215 /* This is a sample TLS 1.0 echo server, for anonymous authentication only.
 216  */
 217
 218 #define SA struct sockaddr
 219 #define MAX_BUF 1024
 220 #define PORT 5556               /* listen to 5556 port */
 221 #define DH_BITS 1024
 222
 223 /* These are global */
 224 gnutls_anon_server_credentials_t anoncred;
 225
 226 gnutls_session_t
 227 initialize_tls_session (void)
 228 {
 229   gnutls_session_t session;
 230   const int kx_prio[] = { GNUTLS_KX_ANON_DH, 0 };
 231
 232   gnutls_init (&session, GNUTLS_SERVER);
 233
 234   /* avoid calling all the priority functions, since the defaults
 235    * are adequate.
 236    */
 237   gnutls_set_default_priority (session);
 238   gnutls_kx_set_priority (session, kx_prio);
 239
 240   gnutls_credentials_set (session, GNUTLS_CRD_ANON, anoncred);
 241
 242   gnutls_dh_set_prime_bits (session, DH_BITS);
 243
 244   if (TLS_SESSION_CACHE != 0)
 245     {
 246       gnutls_db_set_retrieve_function (session, wrap_db_fetch);
 247       gnutls_db_set_remove_function (session, wrap_db_delete);
 248       gnutls_db_set_store_function (session, wrap_db_store);
 249       gnutls_db_set_ptr (session, NULL);
 250     }
 251
 252   return session;
 253 }
 254
 255 static gnutls_dh_params_t dh_params;
 256
 257 static int
 258 generate_dh_params (void)
 259 {
 260   const gnutls_datum_t p3 = { pkcs3, strlen (pkcs3) };
 261   /* Generate Diffie Hellman parameters - for use with DHE
 262    * kx algorithms. These should be discarded and regenerated
 263    * once a day, once a week or once a month. Depending on the
 264    * security requirements.
 265    */
 266   gnutls_dh_params_init (&dh_params);
 267   return gnutls_dh_params_import_pkcs3 (dh_params, &p3, GNUTLS_X509_FMT_PEM);
 268 }
 269
 270 int err, listen_sd, i;
 271 int sd, ret;
 272 struct sockaddr_in sa_serv;
 273 struct sockaddr_in sa_cli;
 274 int client_len;
 275 char topbuf[512];
 276 gnutls_session_t session;
 277 char buffer[MAX_BUF + 1];
 278 int optval = 1;
 279
 280 void
 281 global_start (void)
 282 {
 283   /* this must be called once in the program, it is mostly for the server.
 284    */
 285   gnutls_global_init ();
 286
 287   gnutls_anon_allocate_server_credentials (&anoncred);
 288
 289   success ("Launched, generating DH parameters...\n");
 290
 291   generate_dh_params ();
 292
 293   gnutls_anon_set_server_dh_params (anoncred, dh_params);
 294
 295   if (TLS_SESSION_CACHE != 0)
 296     {
 297       wrap_db_init ();
 298     }
 299
 300   /* Socket operations
 301    */
 302   listen_sd = socket (AF_INET, SOCK_STREAM, 0);
 303   if (err == -1)
 304     {
 305       perror ("socket");
 306       fail ("server: socket failed\n");
 307       return;
 308     }
 309
 310   memset (&sa_serv, '\0', sizeof (sa_serv));
 311   sa_serv.sin_family = AF_INET;
 312   sa_serv.sin_addr.s_addr = INADDR_ANY;
 313   sa_serv.sin_port = htons (PORT);      /* Server Port number */
 314
 315   setsockopt (listen_sd, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof (int));
 316
 317   err = bind (listen_sd, (SA *) & sa_serv, sizeof (sa_serv));
 318   if (err == -1)
 319     {
 320       perror ("bind");
 321       fail ("server: bind failed\n");
 322       return;
 323     }
 324
 325   err = listen (listen_sd, 1024);
 326   if (err == -1)
 327     {
 328       perror ("listen");
 329       fail ("server: listen failed\n");
 330       return;
 331     }
 332
 333   success ("server: ready. Listening to port '%d'.\n", PORT);
 334 }
 335
 336 void
 337 global_stop (void)
 338 {
 339   success ("global stop\n");
 340
 341   gnutls_anon_free_server_credentials (anoncred);
 342
 343   gnutls_dh_params_deinit (dh_params);
 344
 345   gnutls_global_deinit ();
 346 }
 347
 348 void
 349 server (void)
 350 {
 351   int t;
 352
 353   for (t = 0; t < 2; t++)
 354     {
 355       client_len = sizeof (sa_cli);
 356
 357       session = initialize_tls_session ();
 358
 359       sd = accept (listen_sd, (SA *) & sa_cli, &client_len);
 360
 361       success ("server: connection from %s, port %d\n",
 362                inet_ntop (AF_INET, &sa_cli.sin_addr, topbuf,
 363                           sizeof (topbuf)), ntohs (sa_cli.sin_port));
 364
 365       gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) sd);
 366       ret = gnutls_handshake (session);
 367       if (ret < 0)
 368         {
 369           close (sd);
 370           gnutls_deinit (session);
 371           fail ("server: Handshake has failed (%s)\n\n",
 372                 gnutls_strerror (ret));
 373           return;
 374         }
 375       success ("server: Handshake was completed\n");
 376
 377       /* see the Getting peer's information example */
 378       /* print_info(session); */
 379
 380       i = 0;
 381       for (;;)
 382         {
 383           bzero (buffer, MAX_BUF + 1);
 384           ret = gnutls_record_recv (session, buffer, MAX_BUF);
 385
 386           if (ret == 0)
 387             {
 388               success ("server: Peer has closed the GNUTLS connection\n");
 389               break;
 390             }
 391           else if (ret < 0)
 392             {
 393               fail ("server: Received corrupted data(%d). Closing...\n", ret);
 394               break;
 395             }
 396           else if (ret > 0)
 397             {
 398               /* echo data back to the client
 399                */
 400               gnutls_record_send (session, buffer, strlen (buffer));
 401             }
 402         }
 403       /* do not wait for the peer to close the connection.
 404        */
 405       gnutls_bye (session, GNUTLS_SHUT_WR);
 406
 407       close (sd);
 408
 409       gnutls_deinit (session);
 410     }
 411
 412   close (listen_sd);
 413
 414   success ("server: finished\n");
 415 }
 416
 417 void
 418 doit (void)
 419 {
 420   pid_t child;
 421
 422   global_start ();
 423   if (error_count)
 424     return;
 425
 426   child = fork ();
 427   if (child < 0)
 428     {
 429       perror ("fork");
 430       fail ("fork");
 431       return;
 432     }
 433
 434   if (child)
 435     {
 436       int status;
 437       /* parent */
 438       server ();
 439       wait (&status);
 440     }
 441   else
 442     client ();
 443
 444   global_stop ();
 445 }
 446
 447 /* Functions and other stuff needed for session resuming.
 448  * This is done using a very simple list which holds session ids
 449  * and session data.
 450  */
 451
 452 #define MAX_SESSION_ID_SIZE 32
 453 #define MAX_SESSION_DATA_SIZE 512
 454
 455 typedef struct
 456 {
 457   unsigned char session_id[MAX_SESSION_ID_SIZE];
 458   unsigned int session_id_size;
 459
 460   char session_data[MAX_SESSION_DATA_SIZE];
 461   int session_data_size;
 462 } CACHE;
 463
 464 static CACHE *cache_db;
 465 static int cache_db_ptr = 0;
 466
 467 static void
 468 wrap_db_init (void)
 469 {
 470
 471   /* allocate cache_db */
 472   cache_db = calloc (1, TLS_SESSION_CACHE * sizeof (CACHE));
 473 }
 474
 475 static void
 476 wrap_db_deinit (void)
 477 {
 478   return;
 479 }
 480
 481 static int
 482 wrap_db_store (void *dbf, gnutls_datum_t key, gnutls_datum_t data)
 483 {
 484   success ("resume db storing... (%d-%d)\n", key.size, data.size);
 485
 486   if (debug)
 487     {
 488       unsigned int i;
 489       printf ("key:\n");
 490       for (i = 0; i < key.size; i++)
 491         {
 492           printf ("%02x ", key.data[i] & 0xFF);
 493           if ((i + 1) % 16 == 0)
 494             printf ("\n");
 495         }
 496       printf ("\n");
 497       printf ("data:\n");
 498       for (i = 0; i < data.size; i++)
 499         {
 500           printf ("%02x ", data.data[i] & 0xFF);
 501           if ((i + 1) % 16 == 0)
 502             printf ("\n");
 503         }
 504       printf ("\n");
 505     }
 506
 507   if (cache_db == NULL)
 508     return -1;
 509
 510   if (key.size > MAX_SESSION_ID_SIZE)
 511     return -1;
 512   if (data.size > MAX_SESSION_DATA_SIZE)
 513     return -1;
 514
 515   memcpy (cache_db[cache_db_ptr].session_id, key.data, key.size);
 516   cache_db[cache_db_ptr].session_id_size = key.size;
 517
 518   memcpy (cache_db[cache_db_ptr].session_data, data.data, data.size);
 519   cache_db[cache_db_ptr].session_data_size = data.size;
 520
 521   cache_db_ptr++;
 522   cache_db_ptr %= TLS_SESSION_CACHE;
 523
 524   return 0;
 525 }
 526
 527 static gnutls_datum_t
 528 wrap_db_fetch (void *dbf, gnutls_datum_t key)
 529 {
 530   gnutls_datum_t res = { NULL, 0 };
 531   int i;
 532
 533   success ("resume db fetch... (%d)\n", key.size);
 534   if (debug)
 535     {
 536       unsigned int i;
 537       printf ("key:\n");
 538       for (i = 0; i < key.size; i++)
 539         {
 540           printf ("%02x ", key.data[i] & 0xFF);
 541           if ((i + 1) % 16 == 0)
 542             printf ("\n");
 543         }
 544       printf ("\n");
 545     }
 546
 547   if (cache_db == NULL)
 548     return res;
 549
 550   for (i = 0; i < TLS_SESSION_CACHE; i++)
 551     {
 552       if (key.size == cache_db[i].session_id_size &&
 553           memcmp (key.data, cache_db[i].session_id, key.size) == 0)
 554         {
 555           success ("resume db fetch... return info\n");
 556
 557           res.size = cache_db[i].session_data_size;
 558
 559           res.data = gnutls_malloc (res.size);
 560           if (res.data == NULL)
 561             return res;
 562
 563           memcpy (res.data, cache_db[i].session_data, res.size);
 564
 565           if (debug)
 566             {
 567               unsigned int i;
 568               printf ("data:\n");
 569               for (i = 0; i < res.size; i++)
 570                 {
 571                   printf ("%02x ", res.data[i] & 0xFF);
 572                   if ((i + 1) % 16 == 0)
 573                     printf ("\n");
 574                 }
 575               printf ("\n");
 576             }
 577
 578           return res;
 579         }
 580     }
 581   return res;
 582 }
 583
 584 static int
 585 wrap_db_delete (void *dbf, gnutls_datum_t key)
 586 {
 587   int i;
 588
 589   if (cache_db == NULL)
 590     return -1;
 591
 592   for (i = 0; i < TLS_SESSION_CACHE; i++)
 593     {
 594       if (key.size == cache_db[i].session_id_size &&
 595           memcmp (key.data, cache_db[i].session_id, key.size) == 0)
 596         {
 597
 598           cache_db[i].session_id_size = 0;
 599           cache_db[i].session_data_size = 0;
 600
 601           return 0;
 602         }
 603     }
 604
 605   return -1;
 606
 607 }