git.distorted.org.uk Git - u/mdw/catacomb/blob - catcrypt.c

   1 /* -*-c-*-
   2  *
   3  * $Id$
   4  *
   5  * Command-line encryption tool
   6  *
   7  * (c) 2004 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of Catacomb.
  13  *
  14  * Catacomb is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU Library General Public License as
  16  * published by the Free Software Foundation; either version 2 of the
  17  * License, or (at your option) any later version.
  18  *
  19  * Catacomb is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU Library General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU Library General Public
  25  * License along with Catacomb; if not, write to the Free
  26  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  27  * MA 02111-1307, USA.
  28  */
  29
  30 /*----- Header files ------------------------------------------------------*/
  31
  32 #include "config.h"
  33
  34 #include <errno.h>
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38
  39 #include <mLib/base64.h>
  40 #include <mLib/dstr.h>
  41 #include <mLib/mdwopt.h>
  42 #include <mLib/quis.h>
  43 #include <mLib/report.h>
  44 #include <mLib/sub.h>
  45
  46 #include "buf.h"
  47 #include "rand.h"
  48 #include "noise.h"
  49 #include "mprand.h"
  50 #include "key.h"
  51 #include "cc.h"
  52
  53 #include "ectab.h"
  54 #include "ptab.h"
  55
  56 /*----- Static variables --------------------------------------------------*/
  57
  58 static const char *keyring = "keyring";
  59
  60 /*----- Data format -------------------------------------------------------*/
  61
  62 /* --- Overview --- *
  63  *
  64  * The encrypted message is divided into chunks, each preceded by a two-octet
  65  * length.  The chunks don't need to be large -- the idea is that we can
  66  * stream the chunks in and out.
  67  *
  68  * The first chunk is a header.  It contains the decryption key-id, and maybe
  69  * the verification key-id if the message is signed.
  70  *
  71  * Next comes the key-encapsulation chunk.  This is decrypted in some
  72  * KEM-specific way to yield a secret hash.  The hash is expanded using an
  73  * MGF (or similar) to make a symmetric encryption and MAC key.
  74  *
  75  * If the message is signed, there comes a signature chunk.  The signature is
  76  * on the header and key-encapsulation chunks, and further output of the MGF.
  77  * This means that the recipient can modify the message and still have a
  78  * valid signature, so it's not useful for proving things to other people;
  79  * but it also means that the recipient knows that the message is from
  80  * someone who knows the hash, which limits the possiblities to (a) whoever
  81  * encrypted the message (good!) and (b) whoever knows the recipient's
  82  * private key.
  83  *
  84  * Then come message chunks.  Each one begins with a MAC over an implicit
  85  * sequence number and the ciphertext.  The final chunk's ciphertext is
  86  * empty; no other chunk is empty.  Thus can the correct end-of-file be
  87  * discerned.
  88  */
  89
  90 /*----- Chunk I/O ---------------------------------------------------------*/
  91
  92 static void chunk_write(enc *e, buf *b)
  93 {
  94   octet l[2];
  95   size_t n = BLEN(b);
  96   assert(n <= MASK16);
  97   STORE16(l, n);
  98   if (e->ops->write(e, l, 2) ||
  99       e->ops->write(e, BBASE(b), BLEN(b)))
 100     die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
 101 }
 102
 103 static void chunk_read(enc *e, dstr *d, buf *b)
 104 {
 105   octet l[2];
 106   size_t n;
 107
 108   dstr_reset(d);
 109   errno = 0;
 110   if (e->ops->read(e, l, 2) != 2)
 111     goto err;
 112   n = LOAD16(l);
 113   dstr_ensure(d, n);
 114   if (e->ops->read(e, d->buf, n) != n)
 115     goto err;
 116   d->len = n;
 117   buf_init(b, d->buf, d->len);
 118   return;
 119
 120 err:
 121   if (!errno) die(EXIT_FAILURE, "unexpected end-of-file on input");
 122   else die(EXIT_FAILURE, "error reading input: %s", strerror(errno));
 123 }
 124
 125 /*----- Encryption --------------------------------------------------------*/
 126
 127 static int encrypt(int argc, char *argv[])
 128 {
 129   const char *of = 0, *kn = "ccrypt", *skn = 0;
 130   FILE *ofp = 0;
 131   FILE *fp = 0;
 132   const char *ef = "binary";
 133   const char *err;
 134   int i;
 135   int en;
 136   size_t n, chsz;
 137   dstr d = DSTR_INIT;
 138   octet *tag, *ct;
 139   buf b;
 140   size_t seq;
 141   char bb[65536];
 142   unsigned f = 0;
 143   key_file kf;
 144   key *k;
 145   key *sk = 0;
 146   kem *km;
 147   sig *s = 0;
 148   gcipher *cx, *c;
 149   gmac *m;
 150   ghash *h;
 151   const encops *eo;
 152   enc *e;
 153
 154 #define f_bogus 1u
 155 #define f_nocheck 2u
 156
 157   for (;;) {
 158     static const struct option opt[] = {
 159       { "key",          OPTF_ARGREQ,    0,      'k' },
 160       { "sign-key",     OPTF_ARGREQ,    0,      's' },
 161       { "armour",       0,              0,      'a' },
 162       { "armor",        0,              0,      'a' },
 163       { "format",       OPTF_ARGREQ,    0,      'f' },
 164       { "output",       OPTF_ARGREQ,    0,      'o' },
 165       { "nocheck",      0,              0,      'C' },
 166       { 0,              0,              0,      0 }
 167     };
 168     i = mdwopt(argc, argv, "k:s:af:o:C", opt, 0, 0, 0);
 169     if (i < 0) break;
 170     switch (i) {
 171       case 'k': kn = optarg; break;
 172       case 's': skn = optarg; break;
 173       case 'a': ef = "pem"; break;
 174       case 'f': ef = optarg; break;
 175       case 'o': of = optarg; break;
 176       case 'C': f |= f_nocheck; break;
 177       default: f |= f_bogus; break;
 178     }
 179   }
 180   if (argc - optind > 1 || (f & f_bogus))
 181     die(EXIT_FAILURE, "Usage: encrypt [-OPTIONS] [FILE]");
 182
 183   if (key_open(&kf, keyring, KOPEN_READ, key_moan, 0))
 184     die(EXIT_FAILURE, "can't open keyring `%s'", keyring);
 185   if ((k = key_bytag(&kf, kn)) == 0)
 186     die(EXIT_FAILURE, "key `%s' not found", kn);
 187   if (skn && (sk = key_bytag(&kf, skn)) == 0)
 188     die(EXIT_FAILURE, "key `%s' not found", skn);
 189
 190   if ((eo = getenc(ef)) == 0)
 191     die(EXIT_FAILURE, "encoding `%s' not found", ef);
 192
 193   if (optind == argc)
 194     fp = stdin;
 195   else if (strcmp(argv[optind], "-") == 0) {
 196     fp = stdin;
 197     optind++;
 198   } else if ((fp = fopen(argv[optind], "rb")) == 0) {
 199     die(EXIT_FAILURE, "couldn't open file `%s': %s",
 200         argv[optind], strerror(errno));
 201   } else
 202     optind++;
 203
 204   if (!of || strcmp(of, "-") == 0)
 205     ofp = stdout;
 206   else if ((ofp = fopen(of, eo->wmode)) == 0) {
 207     die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 208         ofp, strerror(errno));
 209   }
 210
 211   dstr_reset(&d);
 212   key_fulltag(k, &d);
 213   e = initenc(eo, ofp, "CATCRYPT ENCRYPTED MESSAGE");
 214   km = getkem(k, "cckem", 0);
 215   if (!(f & f_nocheck) && (err = km->ops->check(km)) != 0)
 216     moan("key %s fails check: %s", d.buf, err);
 217   if (sk) {
 218     dstr_reset(&d);
 219     key_fulltag(sk, &d);
 220     s = getsig(sk, "ccsig", 1);
 221     if ((err = s->ops->check(s)) != 0)
 222       moan("key %s fails check: %s", d.buf, err);
 223   }
 224
 225   /* --- Build the header chunk --- */
 226
 227   dstr_reset(&d);
 228   dstr_ensure(&d, 256);
 229   buf_init(&b, d.buf, 256);
 230   buf_putu32(&b, k->id);
 231   if (sk) buf_putu32(&b, sk->id);
 232   assert(BOK(&b));
 233   if (s) GH_HASHBUF16(s->h, BBASE(&b), BLEN(&b));
 234   chunk_write(e, &b);
 235
 236   /* --- Build the KEM chunk --- */
 237
 238   dstr_reset(&d);
 239   if (setupkem(km, &d, &cx, &c, &m))
 240     die(EXIT_FAILURE, "failed to encapsulate key");
 241   buf_init(&b, d.buf, d.len);
 242   BSTEP(&b, d.len);
 243   if (s) GH_HASHBUF16(s->h, BBASE(&b), BLEN(&b));
 244   chunk_write(e, &b);
 245
 246   /* --- Write the signature chunk --- */
 247
 248   if (s) {
 249     GC_ENCRYPT(cx, 0, bb, 1024);
 250     GH_HASH(s->h, bb, 1024);
 251     dstr_reset(&d);
 252     if ((en = s->ops->doit(s, &d)) != 0)
 253       die(EXIT_FAILURE, "error creating signature: %s", key_strerror(en));
 254     buf_init(&b, d.buf, d.len);
 255     BSTEP(&b, d.len);
 256     chunk_write(e, &b);
 257   }
 258
 259   /* --- Now do the main crypto --- */
 260
 261   assert(GC_CLASS(c)->blksz <= sizeof(bb));
 262   dstr_ensure(&d, sizeof(bb) + GM_CLASS(m)->hashsz);
 263   seq = 0;
 264   chsz = MASK16 - GM_CLASS(m)->hashsz;
 265   for (;;) {
 266     h = GM_INIT(m);
 267     GH_HASHU32(h, seq);
 268     seq++;
 269     if (GC_CLASS(c)->blksz) {
 270       GC_ENCRYPT(cx, 0, bb, GC_CLASS(c)->blksz);
 271       GC_SETIV(c, bb);
 272     }
 273     n = fread(bb, 1, chsz, fp);
 274     if (!n) break;
 275     buf_init(&b, d.buf, d.sz);
 276     tag = buf_get(&b, GM_CLASS(m)->hashsz);
 277     ct = buf_get(&b, n);
 278     assert(tag); assert(ct);
 279     GC_ENCRYPT(c, bb, ct, n);
 280     GH_HASH(h, ct, n);
 281     GH_DONE(h, tag);
 282     GH_DESTROY(h);
 283     chunk_write(e, &b);
 284   }
 285
 286   /* --- Final terminator packet --- */
 287
 288   buf_init(&b, d.buf, d.sz);
 289   tag = buf_get(&b, GM_CLASS(m)->hashsz);
 290   assert(tag);
 291   GH_DONE(h, tag);
 292   GH_DESTROY(h);
 293   chunk_write(e, &b);
 294
 295   /* --- All done --- */
 296
 297   e->ops->encdone(e);
 298   GM_DESTROY(m);
 299   GC_DESTROY(c);
 300   GC_DESTROY(cx);
 301   freeenc(e);
 302   if (s) freesig(s);
 303   freekem(km);
 304   if (fp != stdin) fclose(fp);
 305   if (of) fclose(ofp);
 306   key_close(&kf);
 307   dstr_destroy(&d);
 308   return (0);
 309
 310 #undef f_bogus
 311 #undef f_nocheck
 312 }
 313
 314 /*---- Decryption ---------------------------------------------------------*/
 315
 316 static int decrypt(int argc, char *argv[])
 317 {
 318   const char *of = 0;
 319   FILE *ofp = 0, *rfp = 0;
 320   FILE *fp = 0;
 321   const char *ef = "binary";
 322   int i;
 323   size_t n;
 324   dstr d = DSTR_INIT;
 325   buf b;
 326   key_file kf;
 327   size_t seq;
 328   uint32 id;
 329   key *k;
 330   key *sk = 0;
 331   kem *km;
 332   sig *s = 0;
 333   gcipher *cx;
 334   gcipher *c;
 335   ghash *h;
 336   gmac *m;
 337   octet *tag;
 338   unsigned f = 0;
 339   const encops *eo;
 340   const char *err;
 341   int verb = 1;
 342   enc *e;
 343
 344 #define f_bogus 1u
 345 #define f_buffer 2u
 346 #define f_nocheck 4u
 347
 348   for (;;) {
 349     static const struct option opt[] = {
 350       { "armour",       0,              0,      'a' },
 351       { "armor",        0,              0,      'a' },
 352       { "buffer",       0,              0,      'b' },
 353       { "verbose",      0,              0,      'v' },
 354       { "quiet",        0,              0,      'q' },
 355       { "nocheck",      0,              0,      'C' },
 356       { "format",       OPTF_ARGREQ,    0,      'f' },
 357       { "output",       OPTF_ARGREQ,    0,      'o' },
 358       { 0,              0,              0,      0 }
 359     };
 360     i = mdwopt(argc, argv, "abf:o:qvC", opt, 0, 0, 0);
 361     if (i < 0) break;
 362     switch (i) {
 363       case 'a': ef = "pem"; break;
 364       case 'b': f |= f_buffer; break;
 365       case 'v': verb++; break;
 366       case 'q': if (verb) verb--; break;
 367       case 'C': f |= f_nocheck; break;
 368       case 'f': ef = optarg; break;
 369       case 'o': of = optarg; break;
 370       default: f |= f_bogus; break;
 371     }
 372   }
 373   if (argc - optind > 1 || (f & f_bogus))
 374     die(EXIT_FAILURE, "Usage: decrypt [-OPTIONS] [FILE]");
 375
 376   if ((eo = getenc(ef)) == 0)
 377     die(EXIT_FAILURE, "encoding `%s' not found", ef);
 378
 379   if (optind == argc)
 380     fp = stdin;
 381   else if (strcmp(argv[optind], "-") == 0) {
 382     fp = stdin;
 383     optind++;
 384   } else if ((fp = fopen(argv[optind], eo->rmode)) == 0) {
 385     die(EXIT_FAILURE, "couldn't open file `%s': %s",
 386         argv[optind], strerror(errno));
 387   } else
 388     optind++;
 389
 390   if (key_open(&kf, keyring, KOPEN_READ, key_moan, 0))
 391     die(EXIT_FAILURE, "can't open keyring `%s'", keyring);
 392
 393   e = initdec(eo, fp, checkbdry, "CATCRYPT ENCRYPTED MESSAGE");
 394
 395   /* --- Read the header chunk --- */
 396
 397   chunk_read(e, &d, &b);
 398   if (buf_getu32(&b, &id)) {
 399     if (verb) printf("FAIL malformed header: missing keyid\n");
 400     exit(EXIT_FAILURE);
 401   }
 402   if ((k = key_byid(&kf, id)) == 0) {
 403     if (verb) printf("FAIL key id %08lx not found\n", (unsigned long)id);
 404     exit(EXIT_FAILURE);
 405   }
 406   if (BLEFT(&b)) {
 407     if (buf_getu32(&b, &id)) {
 408       if (verb) printf("FAIL malformed header: missing signature keyid\n");
 409       exit(EXIT_FAILURE);
 410     }
 411     if ((sk = key_byid(&kf, id)) == 0) {
 412       if (verb) printf("FAIL key id %08lx not found\n", (unsigned long)id);
 413       exit(EXIT_FAILURE);
 414     }
 415   }
 416   if (BLEFT(&b)) {
 417     if (verb) printf("FAIL malformed header: junk at end\n");
 418     exit(EXIT_FAILURE);
 419   }
 420   if (sk) {
 421     s = getsig(sk, "ccsig", 0);
 422     if (!(f & f_nocheck) && verb && (err = s->ops->check(s)) != 0) {
 423       dstr_reset(&d);
 424       key_fulltag(sk, &d);
 425       printf("WARN verification key %s fails check: %s\n", d.buf, err);
 426     }
 427     GH_HASHBUF16(s->h, BBASE(&b), BSZ(&b));
 428   }
 429
 430   /* --- Find the key --- */
 431
 432   km = getkem(k, "cckem", 1);
 433
 434   /* --- Read the KEM chunk --- */
 435
 436   chunk_read(e, &d, &b);
 437   if (setupkem(km, &d, &cx, &c, &m)) {
 438     if (verb) printf("FAIL failed to decapsulate key\n");
 439     exit(EXIT_FAILURE);
 440   }
 441   if (s) GH_HASHBUF16(s->h, d.buf, d.len);
 442
 443   /* --- Verify the signature, if there is one --- */
 444
 445   if (sk) {
 446     dstr_reset(&d);
 447     dstr_ensure(&d, 1024);
 448     GC_ENCRYPT(cx, 0, d.buf, 1024);
 449     GH_HASH(s->h, d.buf, 1024);
 450     chunk_read(e, &d, &b);
 451     if (s->ops->doit(s, &d)) {
 452       if (verb) printf("FAIL signature verification failed\n");
 453       exit(EXIT_FAILURE);
 454     }
 455     if (verb) {
 456       dstr_reset(&d);
 457       key_fulltag(sk, &d);
 458       printf("INFO good-signature %s\n", d.buf);
 459     }
 460     freesig(s);
 461   } else if (verb)
 462     printf("INFO no-signature\n");
 463
 464   /* --- Now decrypt the main body --- */
 465
 466   if (!of || strcmp(of, "-") == 0) {
 467     ofp = stdout;
 468     f |= f_buffer;
 469   }
 470   if (!(f & f_buffer)) {
 471     if ((ofp = fopen(of, "wb")) == 0) {
 472       die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 473           ofp, strerror(errno));
 474     }
 475     rfp = ofp;
 476   } else if ((rfp = tmpfile()) == 0)
 477     die(EXIT_FAILURE, "couldn't create temporary file: %s", strerror(errno));
 478
 479   seq = 0;
 480   dstr_ensure(&d, GC_CLASS(c)->blksz);
 481   dstr_ensure(&d, 4);
 482   for (;;) {
 483     if (GC_CLASS(c)->blksz) {
 484       GC_ENCRYPT(cx, 0, d.buf, GC_CLASS(c)->blksz);
 485       GC_SETIV(c, d.buf);
 486     }
 487     h = GM_INIT(m);
 488     GH_HASHU32(h, seq);
 489     seq++;
 490     chunk_read(e, &d, &b);
 491     if ((tag = buf_get(&b, GM_CLASS(m)->hashsz)) == 0) {
 492       if (verb) printf("FAIL bad ciphertext chunk: no tag\n");
 493       exit(EXIT_FAILURE);
 494     }
 495     GH_HASH(h, BCUR(&b), BLEFT(&b));
 496     if (memcmp(tag, GH_DONE(h, 0), GM_CLASS(m)->hashsz) != 0) {
 497       if (verb)
 498         printf("FAIL bad ciphertext chunk: authentication failure\n");
 499       exit(EXIT_FAILURE);
 500     }
 501     GH_DESTROY(h);
 502     if (!BLEFT(&b))
 503       break;
 504     GC_DECRYPT(c, BCUR(&b), BCUR(&b), BLEFT(&b));
 505     if (fwrite(BCUR(&b), 1, BLEFT(&b), rfp) != BLEFT(&b)) {
 506       if (verb) printf("FAIL error writing output: %s\n", strerror(errno));
 507       exit(EXIT_FAILURE);
 508     }
 509   }
 510
 511   if (fflush(rfp) || ferror(rfp)) {
 512     if (verb) printf("FAIL error writing output: %s\n", strerror(errno));
 513     exit(EXIT_FAILURE);
 514   }
 515   if (f & f_buffer) {
 516     if (!ofp && (ofp = fopen(of, "wb")) == 0) {
 517       die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 518           of, strerror(errno));
 519     }
 520     rewind(rfp);
 521     dstr_reset(&d);
 522     dstr_ensure(&d, 65536);
 523     if (verb && ofp == stdout) printf("DATA\n");
 524     for (;;) {
 525       n = fread(d.buf, 1, d.sz, rfp);
 526       if (!n) break;
 527       if (fwrite(d.buf, 1, n, ofp) < n)
 528         die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
 529     }
 530     if (ferror(rfp) || fclose(rfp))
 531       die(EXIT_FAILURE, "error unbuffering output: %s", strerror(errno));
 532   }
 533
 534   e->ops->decdone(e);
 535   if (verb && ofp != stdout)
 536     printf("OK decrypted successfully\n");
 537   if (ofp && (fflush(ofp) || ferror(ofp) || fclose(ofp)))
 538       die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
 539   freeenc(e);
 540   GC_DESTROY(c);
 541   GC_DESTROY(cx);
 542   GM_DESTROY(m);
 543   freekem(km);
 544   if (fp != stdin) fclose(fp);
 545   key_close(&kf);
 546   dstr_destroy(&d);
 547   return (0);
 548
 549 #undef f_bogus
 550 #undef f_buffer
 551 #undef f_nocheck
 552 }
 553
 554 /*----- Main code ---------------------------------------------------------*/
 555
 556 #define LISTS(LI)                                                       \
 557   LI("Lists", list,                                                     \
 558      listtab[i].name, listtab[i].name)                                  \
 559   LI("Key-encapsulation mechanisms", kem,                               \
 560      kemtab[i].name, kemtab[i].name)                                    \
 561   LI("Signature schemes", sig,                                          \
 562      sigtab[i].name, sigtab[i].name)                                    \
 563   LI("Encodings", enc,                                                  \
 564      enctab[i].name, enctab[i].name)                                    \
 565   LI("Symmetric encryption algorithms", cipher,                         \
 566      gciphertab[i], gciphertab[i]->name)                                \
 567   LI("Hash functions", hash,                                            \
 568      ghashtab[i], ghashtab[i]->name)                                    \
 569   LI("Message authentication codes", mac,                               \
 570      gmactab[i], gmactab[i]->name)
 571
 572 MAKELISTTAB(listtab, LISTS)
 573
 574 int cmd_show(int argc, char *argv[])
 575 {
 576   return (displaylists(listtab, argv + 1));
 577 }
 578
 579 static int cmd_help(int, char **);
 580
 581 static cmd cmdtab[] = {
 582   { "help", cmd_help, "help [COMMAND...]" },
 583   { "show", cmd_show, "show [ITEM...]" },
 584   CMD_ENCODE,
 585   CMD_DECODE,
 586   { "encrypt", encrypt,
 587     "encrypt [-aC] [-k TAG] [-s TAG] [-f FORMAT]\n\t\
 588 [-o OUTPUT] [FILE]", "\
 589 Options:\n\
 590 \n\
 591 -a, --armour            Same as `-f pem'.\n\
 592 -f, --format=FORMAT     Encode as FORMAT.\n\
 593 -k, --key=TAG           Use public encryption key named by TAG.\n\
 594 -s, --sign-key=TAG      Use private signature key named by TAG.\n\
 595 -o, --output=FILE       Write output to FILE.\n\
 596 -C, --nocheck           Don't check the public key.\n\
 597 " },
 598   { "decrypt", decrypt,
 599     "decrypt [-abqvC] [-f FORMAT] [-o OUTPUT] [FILE]", "\
 600 Options:\n\
 601 \n\
 602 -a, --armour            Same as `-f pem'.\n\
 603 -b, --buffer            Buffer output until we're sure we have it all.\n\
 604 -f, --format=FORMAT     Decode as FORMAT.\n\
 605 -o, --output=FILE       Write output to FILE.\n\
 606 -q, --quiet             Produce fewer messages.\n\
 607 -v, --verbose           Produce more verbose messages.\n\
 608 -C, --nocheck           Don't check the private key.\n\
 609 " }, /* ' emacs is confused */
 610   { 0, 0, 0 }
 611 };
 612
 613 static int cmd_help(int argc, char **argv)
 614 {
 615   sc_help(cmdtab, stdout, argv + 1);
 616   return (0);
 617 }
 618
 619 void version(FILE *fp)
 620 {
 621   pquis(fp, "$, Catacomb version " VERSION "\n");
 622 }
 623
 624 static void usage(FILE *fp)
 625 {
 626   pquis(fp, "Usage: $ [-k KEYRING] COMMAND [ARGS]\n");
 627 }
 628
 629 void help_global(FILE *fp)
 630 {
 631   usage(fp);
 632   fputs("\n\
 633 Encrypt and decrypt files.\n\
 634 \n\
 635 Global command-line options:\n\
 636 \n\
 637 -h, --help [COMMAND...] Show this help message, or help for COMMANDs.\n\
 638 -v, --version           Show program version number.\n\
 639 -u, --usage             Show a terse usage message.\n\
 640 \n\
 641 -k, --keyring=FILE      Read keys from FILE.\n",
 642         fp);
 643 }
 644
 645 /* --- @main@ --- *
 646  *
 647  * Arguments:   @int argc@ = number of command line arguments
 648  *              @char *argv[]@ = vector of command line arguments
 649  *
 650  * Returns:     Zero if successful, nonzero otherwise.
 651  *
 652  * Use:         Encrypts or decrypts files.
 653  */
 654
 655 int main(int argc, char *argv[])
 656 {
 657   unsigned f = 0;
 658
 659 #define f_bogus 1u
 660
 661   /* --- Initialize the library --- */
 662
 663   ego(argv[0]);
 664   sub_init();
 665   rand_noisesrc(RAND_GLOBAL, &noise_source);
 666   rand_seed(RAND_GLOBAL, 160);
 667
 668   /* --- Parse options --- */
 669
 670   for (;;) {
 671     static struct option opts[] = {
 672       { "help",         0,              0,      'h' },
 673       { "version",      0,              0,      'v' },
 674       { "usage",        0,              0,      'u' },
 675       { "keyring",      OPTF_ARGREQ,    0,      'k' },
 676       { 0,              0,              0,      0 }
 677     };
 678     int i = mdwopt(argc, argv, "+hvu k:", opts, 0, 0, 0);
 679     if (i < 0)
 680       break;
 681     switch (i) {
 682       case 'h':
 683         sc_help(cmdtab, stdout, argv + optind);
 684         exit(0);
 685         break;
 686       case 'v':
 687         version(stdout);
 688         exit(0);
 689         break;
 690       case 'u':
 691         usage(stdout);
 692         exit(0);
 693       case 'k':
 694         keyring = optarg;
 695         break;
 696       default:
 697         f |= f_bogus;
 698         break;
 699     }
 700   }
 701
 702   argc -= optind;
 703   argv += optind;
 704   optind = 0;
 705   if (f & f_bogus || argc < 1) {
 706     usage(stderr);
 707     exit(EXIT_FAILURE);
 708   }
 709
 710   /* --- Dispatch to the correct subcommand handler --- */
 711
 712   return (findcmd(cmdtab, argv[0])->cmd(argc, argv));
 713
 714 #undef f_bogus
 715 }
 716
 717 /*----- That's all, folks -------------------------------------------------*/