src/openac/openac.c

   1 /**
   2  * @file openac.c
   3  *
   4  * @brief Generation of X.509 attribute certificates.
   5  *
   6  */
   7
   8 /*
   9  * Copyright (C) 2002  Ueli Galizzi, Ariane Seiler
  10  * Copyright (C) 2004,2007  Andreas Steffen
  11  * Hochschule fuer Technik Rapperswil, Switzerland
  12  *
  13  * This program is free software; you can redistribute it and/or modify it
  14  * under the terms of the GNU General Public License as published by the
  15  * Free Software Foundation; either version 2 of the License, or (at your
  16  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  17  *
  18  * This program is distributed in the hope that it will be useful, but
  19  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  20  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  21  * for more details.
  22  *
  23  * RCSID $Id$
  24  */
  25
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <syslog.h>
  30 #include <unistd.h>
  31 #include <getopt.h>
  32 #include <ctype.h>
  33 #include <time.h>
  34 #include <gmp.h>
  35
  36 #include <library.h>
  37 #include <debug.h>
  38 #include <asn1/asn1.h>
  39 #include <asn1/pem.h>
  40 #include <credentials/certificates/x509.h>
  41 #include <credentials/certificates/ac.h>
  42 #include <utils/optionsfrom.h>
  43
  44 #ifdef INTEGRITY_TEST
  45 #include <fips/fips.h>
  46 #include <fips_signature.h>
  47 #endif /* INTEGRITY_TEST */
  48
  49 #define OPENAC_PATH             IPSEC_CONFDIR "/openac"
  50 #define OPENAC_SERIAL           IPSEC_CONFDIR "/openac/serial"
  51
  52 #define DEFAULT_VALIDITY        24*3600         /* seconds */
  53
  54 /**
  55  * @brief prints the usage of the program to the stderr
  56  */
  57 static void usage(const char *message)
  58 {
  59         if (message != NULL && *message != '\0')
  60         {
  61                 fprintf(stderr, "%s\n", message);
  62         }
  63         fprintf(stderr, "Usage: openac"
  64                 " [--help]"
  65                 " [--version]"
  66                 " [--optionsfrom <filename>]"
  67                 " [--quiet]"
  68                 " \\\n\t"
  69                 "      [--debug <level 0..4>]"
  70                 " \\\n\t"
  71                 "      [--days <days>]"
  72                 " [--hours <hours>]"
  73                 " \\\n\t"
  74                 "      [--startdate <YYYYMMDDHHMMSSZ>]"
  75                 " [--enddate <YYYYMMDDHHMMSSZ>]"
  76                 " \\\n\t"
  77                 "      --cert <certfile>"
  78                 " --key <keyfile>"
  79                 " [--password <password>]"
  80                 " \\\n\t"
  81                 "      --usercert <certfile>"
  82                 " --groups <attr1,attr2,..>"
  83                 " --out <filename>"
  84                 "\n"
  85         );
  86 }
  87
  88
  89 /**
  90  * convert a chunk into a multi-precision integer
  91  */
  92 static void chunk_to_mpz(chunk_t chunk, mpz_t number)
  93 {
  94         mpz_import(number, chunk.len, 1, 1, 1, 0, chunk.ptr);
  95 }
  96
  97 /**
  98  * convert a multi-precision integer into a chunk
  99  */
 100 static chunk_t mpz_to_chunk(mpz_t number)
 101 {
 102         chunk_t chunk;
 103
 104         chunk.len = 1 + mpz_sizeinbase(number, 2)/BITS_PER_BYTE;
 105         chunk.ptr = mpz_export(NULL, NULL, 1, chunk.len, 1, 0, number);
 106         return chunk;
 107 }
 108
 109 /**
 110  * read the last serial number from file
 111  */
 112 static chunk_t read_serial(void)
 113 {
 114         mpz_t number;
 115
 116         char buf[BUF_LEN], buf1[BUF_LEN];
 117         chunk_t hex_serial  = { buf, BUF_LEN };
 118         chunk_t last_serial = { buf1, BUF_LEN };
 119         chunk_t serial;
 120
 121         FILE *fd = fopen(OPENAC_SERIAL, "r");
 122
 123         /* last serial number defaults to 0 */
 124         *last_serial.ptr = 0x00;
 125         last_serial.len = 1;
 126
 127         if (fd)
 128         {
 129                 if (fscanf(fd, "%s", hex_serial.ptr))
 130                 {
 131                         hex_serial.len = strlen(hex_serial.ptr);
 132                         last_serial = chunk_from_hex(hex_serial, last_serial.ptr);
 133                 }
 134                 fclose(fd);
 135         }
 136         else
 137         {
 138                 DBG1("  file '%s' does not exist yet - serial number set to 01", OPENAC_SERIAL);
 139         }
 140
 141         /**
 142          * conversion of read serial number to a multiprecision integer
 143          * and incrementing it by one
 144          * and representing it as a two's complement octet string
 145          */
 146         mpz_init(number);
 147         chunk_to_mpz(last_serial, number);
 148         mpz_add_ui(number, number, 0x01);
 149         serial = mpz_to_chunk(number);
 150         mpz_clear(number);
 151
 152         return serial;
 153 }
 154
 155 /**
 156  * write back the last serial number to file
 157  */
 158 static void write_serial(chunk_t serial)
 159 {
 160         FILE *fd = fopen(OPENAC_SERIAL, "w");
 161
 162         if (fd)
 163         {
 164                 chunk_t hex_serial;
 165
 166                 DBG1("  serial number is %#B", &serial);
 167                 hex_serial = chunk_to_hex(serial, NULL, FALSE);
 168                 fprintf(fd, "%.*s\n", hex_serial.len, hex_serial.ptr);
 169                 fclose(fd);
 170                 free(hex_serial.ptr);
 171         }
 172         else
 173         {
 174                 DBG1("  could not open file '%s' for writing", OPENAC_SERIAL);
 175         }
 176 }
 177
 178 /**
 179  * Load and parse a private key file
 180  */
 181 static private_key_t* private_key_create_from_file(char *path, chunk_t *secret)
 182 {
 183         bool pgp = FALSE;
 184         chunk_t chunk = chunk_empty;
 185         private_key_t *key = NULL;
 186
 187         if (!pem_asn1_load_file(path, secret, &chunk, &pgp))
 188         {
 189                 DBG1("  could not load private key file '%s'", path);
 190                 return NULL;
 191         }
 192         key = lib->creds->create(lib->creds, CRED_PRIVATE_KEY, KEY_RSA,
 193                                                          BUILD_BLOB_ASN1_DER, chunk, BUILD_END);
 194         if (key == NULL)
 195         {
 196                 DBG1("  could not parse loaded private key file '%s'", path);
 197                 return NULL;
 198         }
 199         DBG1("  loaded private key file '%s'", path);
 200         return key;
 201 }
 202
 203 /**
 204  * global variables accessible by both main() and build.c
 205  */
 206
 207 static int debug_level = 1;
 208 static bool stderr_quiet = FALSE;
 209
 210 /**
 211  * openac dbg function
 212  */
 213 static void openac_dbg(int level, char *fmt, ...)
 214 {
 215         int priority = LOG_INFO;
 216         va_list args;
 217
 218         if (level <= debug_level)
 219         {
 220                 va_start(args, fmt);
 221                 if (!stderr_quiet)
 222                 {
 223                         vfprintf(stderr, fmt, args);
 224                         fprintf(stderr, "\n");
 225                 }
 226                 vsyslog(priority, fmt, args);
 227                 va_end(args);
 228         }
 229 }
 230
 231 /**
 232  * @brief openac main program
 233  *
 234  * @param argc number of arguments
 235  * @param argv pointer to the argument values
 236  */
 237 int main(int argc, char **argv)
 238 {
 239         certificate_t *attr_cert   = NULL;
 240         certificate_t *userCert   = NULL;
 241         certificate_t *signerCert = NULL;
 242         private_key_t *signerKey  = NULL;
 243
 244         time_t notBefore = UNDEFINED_TIME;
 245         time_t notAfter  = UNDEFINED_TIME;
 246         time_t validity = 0;
 247
 248         char *keyfile = NULL;
 249         char *certfile = NULL;
 250         char *usercertfile = NULL;
 251         char *outfile = NULL;
 252         char *groups = "";
 253         char buf[BUF_LEN];
 254
 255         chunk_t passphrase = { buf, 0 };
 256         chunk_t serial = chunk_empty;
 257         chunk_t attr_chunk = chunk_empty;
 258
 259         int status = 1;
 260
 261         /* enable openac debugging hook */
 262         dbg = openac_dbg;
 263
 264         passphrase.ptr[0] = '\0';
 265
 266         openlog("openac", 0, LOG_AUTHPRIV);
 267
 268         /* initialize library */
 269         library_init(STRONGSWAN_CONF);
 270         lib->plugins->load(lib->plugins, IPSEC_PLUGINDIR, "libstrongswan-");
 271
 272         /* initialize optionsfrom */
 273         options_t *options = options_create();
 274
 275         /* handle arguments */
 276         for (;;)
 277         {
 278                 static const struct option long_opts[] = {
 279                         /* name, has_arg, flag, val */
 280                         { "help", no_argument, NULL, 'h' },
 281                         { "version", no_argument, NULL, 'v' },
 282                         { "optionsfrom", required_argument, NULL, '+' },
 283                         { "quiet", no_argument, NULL, 'q' },
 284                         { "cert", required_argument, NULL, 'c' },
 285                         { "key", required_argument, NULL, 'k' },
 286                         { "password", required_argument, NULL, 'p' },
 287                         { "usercert", required_argument, NULL, 'u' },
 288                         { "groups", required_argument, NULL, 'g' },
 289                         { "days", required_argument, NULL, 'D' },
 290                         { "hours", required_argument, NULL, 'H' },
 291                         { "startdate", required_argument, NULL, 'S' },
 292                         { "enddate", required_argument, NULL, 'E' },
 293                         { "out", required_argument, NULL, 'o' },
 294                         { "debug", required_argument, NULL, 'd' },
 295                         { 0,0,0,0 }
 296                 };
 297
 298                 int c = getopt_long(argc, argv, "hv+:qc:k:p;u:g:D:H:S:E:o:d:", long_opts, NULL);
 299
 300                 /* Note: "breaking" from case terminates loop */
 301                 switch (c)
 302                 {
 303                         case EOF:       /* end of flags */
 304                                 break;
 305
 306                         case 0: /* long option already handled */
 307                                 continue;
 308
 309                         case ':':       /* diagnostic already printed by getopt_long */
 310                         case '?':       /* diagnostic already printed by getopt_long */
 311                         case 'h':       /* --help */
 312                                 usage(NULL);
 313                                 status = 1;
 314                                 goto end;
 315
 316                         case 'v':       /* --version */
 317                                 printf("openac (strongSwan %s)\n", VERSION);
 318                                 status = 0;
 319                                 goto end;
 320
 321                         case '+':       /* --optionsfrom <filename> */
 322                                 {
 323                                         char path[BUF_LEN];
 324
 325                                         if (*optarg == '/')     /* absolute pathname */
 326                                         {
 327                                         strncpy(path, optarg, BUF_LEN);
 328                                         }
 329                                         else                    /* relative pathname */
 330                                         {
 331                                         snprintf(path, BUF_LEN, "%s/%s", OPENAC_PATH, optarg);
 332                                         }
 333                                         if (!options->from(options, path, &argc, &argv, optind))
 334                                         {
 335                                                 status = 1;
 336                                                 goto end;
 337                                         }
 338                                 }
 339                                 continue;
 340
 341                         case 'q':       /* --quiet */
 342                                 stderr_quiet = TRUE;
 343                                 continue;
 344
 345                         case 'c':       /* --cert */
 346                                 certfile = optarg;
 347                                 continue;
 348
 349                         case 'k':       /* --key */
 350                                 keyfile = optarg;
 351                                 continue;
 352
 353                         case 'p':       /* --key */
 354                                 if (strlen(optarg) > BUF_LEN)
 355                                 {
 356                                         usage("passphrase too long");
 357                                         goto end;
 358                                 }
 359                                 strncpy(passphrase.ptr, optarg, BUF_LEN);
 360                                 passphrase.len = min(strlen(optarg), BUF_LEN);
 361                                 continue;
 362
 363                         case 'u':       /* --usercert */
 364                                 usercertfile = optarg;
 365                                 continue;
 366
 367                         case 'g':       /* --groups */
 368                                 groups = optarg;
 369                                 continue;
 370
 371                         case 'D':       /* --days */
 372                                 if (optarg == NULL || !isdigit(optarg[0]))
 373                                 {
 374                                         usage("missing number of days");
 375                                         goto end;
 376                                 }
 377                                 else
 378                                 {
 379                                         char *endptr;
 380                                         long days = strtol(optarg, &endptr, 0);
 381
 382                                         if (*endptr != '\0' || endptr == optarg || days <= 0)
 383                                         {
 384                                                 usage("<days> must be a positive number");
 385                                                 goto end;
 386                                         }
 387                                         validity += 24*3600*days;
 388                                 }
 389                                 continue;
 390
 391                         case 'H':       /* --hours */
 392                                 if (optarg == NULL || !isdigit(optarg[0]))
 393                                 {
 394                                         usage("missing number of hours");
 395                                         goto end;
 396                                 }
 397                                 else
 398                                 {
 399                                         char *endptr;
 400                                         long hours = strtol(optarg, &endptr, 0);
 401
 402                                         if (*endptr != '\0' || endptr == optarg || hours <= 0)
 403                                         {
 404                                                 usage("<hours> must be a positive number");
 405                                                 goto end;
 406                                         }
 407                                         validity += 3600*hours;
 408                                 }
 409                                 continue;
 410
 411                         case 'S':       /* --startdate */
 412                                 if (optarg == NULL || strlen(optarg) != 15 || optarg[14] != 'Z')
 413                                 {
 414                                         usage("date format must be YYYYMMDDHHMMSSZ");
 415                                         goto end;
 416                                 }
 417                                 else
 418                                 {
 419                                         chunk_t date = { optarg, 15 };
 420
 421                                         notBefore = asn1_to_time(&date, ASN1_GENERALIZEDTIME);
 422                                 }
 423                                 continue;
 424
 425                         case 'E':       /* --enddate */
 426                                 if (optarg == NULL || strlen(optarg) != 15 || optarg[14] != 'Z')
 427                                 {
 428                                         usage("date format must be YYYYMMDDHHMMSSZ");
 429                                         goto end;
 430                                 }
 431                                 else
 432                                 {
 433                                         chunk_t date = { optarg, 15 };
 434                                         notAfter = asn1_to_time(&date, ASN1_GENERALIZEDTIME);
 435                                 }
 436                                 continue;
 437
 438                         case 'o':       /* --out */
 439                                 outfile = optarg;
 440                                 continue;
 441
 442                         case 'd':       /* --debug */
 443                                 debug_level = atoi(optarg);
 444                                 continue;
 445
 446                         default:
 447                                 usage("");
 448                                 status = 0;
 449                                 goto end;
 450                 }
 451                 /* break from loop */
 452                 break;
 453         }
 454
 455         if (optind != argc)
 456         {
 457                 usage("unexpected argument");
 458                 goto end;
 459         }
 460
 461         DBG1("starting openac (strongSwan Version %s)", VERSION);
 462
 463 #ifdef INTEGRITY_TEST
 464         DBG1("integrity test of libstrongswan code");
 465         if (fips_verify_hmac_signature(hmac_key, hmac_signature))
 466         {
 467                 DBG1("  integrity test passed");
 468         }
 469         else
 470         {
 471                 DBG1("  integrity test failed");
 472                 status = 3;
 473                 goto end;
 474         }
 475 #endif /* INTEGRITY_TEST */
 476
 477         /* load the signer's RSA private key */
 478         if (keyfile != NULL)
 479         {
 480                 signerKey = private_key_create_from_file(keyfile, &passphrase);
 481
 482                 if (signerKey == NULL)
 483                 {
 484                         goto end;
 485                 }
 486         }
 487
 488         /* load the signer's X.509 certificate */
 489         if (certfile != NULL)
 490         {
 491                 signerCert = lib->creds->create(lib->creds,
 492                                                                                 CRED_CERTIFICATE, CERT_X509,
 493                                                                                 BUILD_FROM_FILE, certfile,
 494                                                                                 BUILD_X509_FLAG, 0,
 495                                                                                 BUILD_END);
 496                 if (signerCert == NULL)
 497                 {
 498                         goto end;
 499                 }
 500         }
 501
 502         /* load the users's X.509 certificate */
 503         if (usercertfile != NULL)
 504         {
 505                 userCert = lib->creds->create(lib->creds,
 506                                                                           CRED_CERTIFICATE, CERT_X509,
 507                                                                           BUILD_FROM_FILE, usercertfile,
 508                                                                           BUILD_X509_FLAG, 0,
 509                                                                           BUILD_END);
 510                 if (userCert == NULL)
 511                 {
 512                         goto end;
 513                 }
 514         }
 515
 516         /* compute validity interval */
 517         validity = (validity)? validity : DEFAULT_VALIDITY;
 518         notBefore = (notBefore == UNDEFINED_TIME) ? time(NULL) : notBefore;
 519         notAfter =  (notAfter  == UNDEFINED_TIME) ? time(NULL) + validity : notAfter;
 520
 521         /* build and parse attribute certificate */
 522         if (userCert != NULL && signerCert != NULL && signerKey != NULL)
 523         {
 524                 /* read the serial number and increment it by one */
 525                 serial = read_serial();
 526
 527                 attr_cert = lib->creds->create(lib->creds,
 528                                                         CRED_CERTIFICATE, CERT_X509_AC,
 529                                                         BUILD_CERT, userCert->get_ref(userCert),
 530                                                         BUILD_NOT_BEFORE_TIME, notBefore,
 531                                                         BUILD_NOT_AFTER_TIME, notAfter,
 532                                                         BUILD_SERIAL, serial,
 533                                                         BUILD_IETF_GROUP_ATTR, groups,
 534                                                         BUILD_SIGNING_CERT, signerCert->get_ref(signerCert),
 535                                                         BUILD_SIGNING_KEY, signerKey->get_ref(signerKey),
 536                                                         BUILD_END);
 537                 if (!attr_cert)
 538                 {
 539                         goto end;
 540                 }
 541
 542                 /* write the attribute certificate to file */
 543                 attr_chunk = attr_cert->get_encoding(attr_cert);
 544                 if (chunk_write(attr_chunk, outfile, 0022, TRUE))
 545                 {
 546                         DBG1("  wrote attribute cert file '%s' (%u bytes)", outfile, attr_chunk.len);
 547                         write_serial(serial);
 548                         status = 0;
 549                 }
 550         }
 551         else
 552         {
 553                 usage("some of the mandatory parameters --usercert --cert --key "
 554                           "are missing");
 555         }
 556
 557 end:
 558         /* delete all dynamically allocated objects */
 559         DESTROY_IF(signerKey);
 560         DESTROY_IF(signerCert);
 561         DESTROY_IF(userCert);
 562         DESTROY_IF(attr_cert);
 563         free(attr_chunk.ptr);
 564         free(serial.ptr);
 565         closelog();
 566         dbg = dbg_default;
 567         options->destroy(options);
 568         library_deinit();
 569         exit(status);
 570 }