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

   1 /* -*-c-*-
   2  *
   3  * Command-line encryption tool
   4  *
   5  * (c) 2004 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Catacomb.
  11  *
  12  * Catacomb is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU Library General Public License as
  14  * published by the Free Software Foundation; either version 2 of the
  15  * License, or (at your option) any later version.
  16  *
  17  * Catacomb is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU Library General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Library General Public
  23  * License along with Catacomb; if not, write to the Free
  24  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  25  * MA 02111-1307, USA.
  26  */
  27
  28 /*----- Header files ------------------------------------------------------*/
  29
  30 #define _FILE_OFFSET_BITS 64
  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/macros.h>
  42 #include <mLib/mdwopt.h>
  43 #include <mLib/quis.h>
  44 #include <mLib/report.h>
  45 #include <mLib/sub.h>
  46
  47 #include "buf.h"
  48 #include "ct.h"
  49 #include "rand.h"
  50 #include "noise.h"
  51 #include "mprand.h"
  52 #include "key.h"
  53 #include "cc.h"
  54
  55 #include "gaead.h"
  56 #include "ectab.h"
  57 #include "ptab.h"
  58
  59 /*----- Static variables --------------------------------------------------*/
  60
  61 static const char *keyring = "keyring";
  62
  63 /*----- Data format -------------------------------------------------------*/
  64
  65 /* --- Overview --- *
  66  *
  67  * The encrypted message is divided into chunks, each preceded by a two-octet
  68  * length.  The chunks don't need to be large -- the idea is that we can
  69  * stream the chunks in and out.
  70  *
  71  * The first chunk is a header.  It contains the decryption key-id, and maybe
  72  * the verification key-id if the message is signed.
  73  *
  74  * Next comes the key-encapsulation chunk.  This is decrypted in some
  75  * KEM-specific way to yield a secret hash.  The hash is expanded using an
  76  * MGF (or similar) to make a symmetric encryption and MAC key.
  77  *
  78  * If the message is signed, there comes a signature chunk.  The signature is
  79  * on the header and key-encapsulation chunks, and further output of the MGF.
  80  * This means that the recipient can modify the message and still have a
  81  * valid signature, so it's not useful for proving things to other people;
  82  * but it also means that the recipient knows that the message is from
  83  * someone who knows the hash, which limits the possiblities to (a) whoever
  84  * encrypted the message (good!) and (b) whoever knows the recipient's
  85  * private key.
  86  *
  87  * Then come message chunks.  Each one begins with a MAC over an implicit
  88  * sequence number and the ciphertext.  The final chunk's ciphertext is
  89  * empty; no other chunk is empty.  Thus can the correct end-of-file be
  90  * discerned.
  91  */
  92
  93 /*----- Chunk I/O ---------------------------------------------------------*/
  94
  95 static void chunk_write(enc *e, buf *b)
  96 {
  97   octet l[2];
  98   size_t n = BLEN(b);
  99   assert(n <= MASK16);
 100   STORE16(l, n);
 101   if (e->ops->write(e, l, 2) ||
 102       e->ops->write(e, BBASE(b), BLEN(b)))
 103     die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
 104 }
 105
 106 static void chunk_read(enc *e, dstr *d, buf *b)
 107 {
 108   octet l[2];
 109   size_t n;
 110
 111   dstr_reset(d);
 112   errno = 0;
 113   if (e->ops->read(e, l, 2) != 2)
 114     goto err;
 115   n = LOAD16(l);
 116   dstr_ensure(d, n);
 117   if (e->ops->read(e, d->buf, n) != n)
 118     goto err;
 119   d->len = n;
 120   buf_init(b, d->buf, d->len);
 121   return;
 122
 123 err:
 124   if (!errno) die(EXIT_FAILURE, "unexpected end-of-file on input");
 125   else die(EXIT_FAILURE, "error reading input: %s", strerror(errno));
 126 }
 127
 128 /*----- Encryption --------------------------------------------------------*/
 129
 130 static int encrypt(int argc, char *argv[])
 131 {
 132   const char *fn, *of = 0, *kn = "ccrypt", *skn = 0;
 133   FILE *ofp = 0;
 134   FILE *fp = 0;
 135   const char *ef = "binary";
 136   fprogress ff;
 137   const char *err;
 138   int i;
 139   int en;
 140   size_t n, chsz;
 141   dstr d = DSTR_INIT;
 142   buf b;
 143   size_t seq;
 144   char bb[65536];
 145   unsigned f = 0;
 146   key_file kf;
 147   key *k;
 148   key *sk = 0;
 149   kem *km;
 150   bulk *bc;
 151   sig *s = 0;
 152   const encops *eo;
 153   enc *e;
 154
 155 #define f_bogus 1u
 156 #define f_nocheck 2u
 157 #define f_progress 4u
 158
 159   for (;;) {
 160     static const struct option opt[] = {
 161       { "key",          OPTF_ARGREQ,    0,      'k' },
 162       { "sign-key",     OPTF_ARGREQ,    0,      's' },
 163       { "armour",       0,              0,      'a' },
 164       { "armor",        0,              0,      'a' },
 165       { "format",       OPTF_ARGREQ,    0,      'f' },
 166       { "output",       OPTF_ARGREQ,    0,      'o' },
 167       { "progress",     0,              0,      'p' },
 168       { "nocheck",      0,              0,      'C' },
 169       { 0,              0,              0,      0 }
 170     };
 171     i = mdwopt(argc, argv, "k:s:af:o:pC", opt, 0, 0, 0);
 172     if (i < 0) break;
 173     switch (i) {
 174       case 'k': kn = optarg; break;
 175       case 's': skn = optarg; break;
 176       case 'a': ef = "pem"; break;
 177       case 'f': ef = optarg; break;
 178       case 'o': of = optarg; break;
 179       case 'p': f |= f_progress; break;
 180       case 'C': f |= f_nocheck; break;
 181       default: f |= f_bogus; break;
 182     }
 183   }
 184   if (argc - optind > 1 || (f & f_bogus))
 185     die(EXIT_FAILURE, "Usage: encrypt [-OPTIONS] [FILE]");
 186
 187   if (key_open(&kf, keyring, KOPEN_READ, key_moan, 0))
 188     die(EXIT_FAILURE, "can't open keyring `%s'", keyring);
 189   if ((k = key_bytag(&kf, kn)) == 0)
 190     die(EXIT_FAILURE, "key `%s' not found", kn);
 191   if (skn && (sk = key_bytag(&kf, skn)) == 0)
 192     die(EXIT_FAILURE, "key `%s' not found", skn);
 193
 194   if ((eo = getenc(ef)) == 0)
 195     die(EXIT_FAILURE, "encoding `%s' not found", ef);
 196
 197   fn = optind < argc ? argv[optind++] : "-";
 198   if (STRCMP(fn, ==, "-"))
 199     fp = stdin;
 200   else if ((fp = fopen(fn, "rb")) == 0) {
 201     die(EXIT_FAILURE, "couldn't open file `%s': %s",
 202         fn, strerror(errno));
 203   }
 204
 205   if (!of || STRCMP(of, ==, "-"))
 206     ofp = stdout;
 207   else if ((ofp = fopen(of, eo->wmode)) == 0) {
 208     die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 209         of, strerror(errno));
 210   }
 211
 212   dstr_reset(&d);
 213   key_fulltag(k, &d);
 214   e = initenc(eo, ofp, "CATCRYPT ENCRYPTED MESSAGE");
 215   km = getkem(k, "cckem", 0, &bc);
 216   if (!(f & f_nocheck) && (err = km->ops->check(km)) != 0)
 217     moan("key %s fails check: %s", d.buf, err);
 218   if (sk) {
 219     dstr_reset(&d);
 220     key_fulltag(sk, &d);
 221     s = getsig(sk, "ccsig", 1);
 222     if ((err = s->ops->check(s)) != 0)
 223       moan("key %s fails check: %s", d.buf, err);
 224   }
 225
 226   /* --- Build the header chunk --- */
 227
 228   dstr_reset(&d);
 229   dstr_ensure(&d, 256);
 230   buf_init(&b, d.buf, 256);
 231   buf_putu32(&b, k->id);
 232   if (sk) buf_putu32(&b, sk->id);
 233   assert(BOK(&b));
 234   if (s) GH_HASHBUF16(s->h, BBASE(&b), BLEN(&b));
 235   chunk_write(e, &b);
 236
 237   /* --- Build the KEM chunk --- */
 238
 239   dstr_reset(&d);
 240   if (setupkem(km, &d, bc)) 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(km->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   if (f & f_progress) {
 262     if (fprogress_init(&ff, fn, fp)) {
 263       die(EXIT_FAILURE, "failed to initialize progress display: %s",
 264           strerror(errno));
 265     }
 266   }
 267
 268   n = bc->ops->overhead(bc);
 269   dstr_ensure(&d, sizeof(bb) + n);
 270   seq = 0;
 271   chsz = MASK16 - n;
 272   do {
 273     n = fread(bb, 1, chsz, fp);
 274     if (f & f_progress) fprogress_update(&ff, n);
 275     buf_init(&b, d.buf, d.sz);
 276     if ((err = bc->ops->doit(bc, seq, &b, bb, n)) != 0) {
 277       if (f & f_progress) fprogress_done(&ff);
 278       die(EXIT_FAILURE, "failed to encrypt packet: %s\n", err);
 279     }
 280     seq++;
 281     chunk_write(e, &b);
 282   } while (n);
 283
 284   /* --- All done --- */
 285
 286   if (f & f_progress) fprogress_done(&ff);
 287   e->ops->encdone(e);
 288   bc->ops->destroy(bc);
 289   freeenc(e);
 290   if (s) freesig(s);
 291   freekem(km);
 292   if (fp != stdin) fclose(fp);
 293   if (of) fclose(ofp);
 294   key_close(&kf);
 295   dstr_destroy(&d);
 296   return (0);
 297
 298 #undef f_bogus
 299 #undef f_nocheck
 300 #undef f_progress
 301 }
 302
 303 /*---- Decryption ---------------------------------------------------------*/
 304
 305 static int decrypt(int argc, char *argv[])
 306 {
 307   const char *fn, *of = 0;
 308   FILE *ofp = 0, *rfp = 0;
 309   FILE *fp = 0;
 310   const char *ef = "binary";
 311   fprogress ff;
 312   int i;
 313   size_t n;
 314   dstr d = DSTR_INIT;
 315   char bb[65536];
 316   buf b;
 317   key_file kf;
 318   size_t seq;
 319   uint32 id;
 320   key *k;
 321   key *sk = 0;
 322   kem *km;
 323   sig *s = 0;
 324   bulk *bc;
 325   unsigned f = 0;
 326   const encops *eo;
 327   const char *err;
 328   int verb = 1;
 329   enc *e;
 330
 331 #define f_bogus 1u
 332 #define f_buffer 2u
 333 #define f_nocheck 4u
 334 #define f_progress 8u
 335
 336   for (;;) {
 337     static const struct option opt[] = {
 338       { "armour",       0,              0,      'a' },
 339       { "armor",        0,              0,      'a' },
 340       { "buffer",       0,              0,      'b' },
 341       { "verbose",      0,              0,      'v' },
 342       { "quiet",        0,              0,      'q' },
 343       { "nocheck",      0,              0,      'C' },
 344       { "format",       OPTF_ARGREQ,    0,      'f' },
 345       { "output",       OPTF_ARGREQ,    0,      'o' },
 346       { "progress",     0,              0,      'p' },
 347       { 0,              0,              0,      0 }
 348     };
 349     i = mdwopt(argc, argv, "abf:o:pqvC", opt, 0, 0, 0);
 350     if (i < 0) break;
 351     switch (i) {
 352       case 'a': ef = "pem"; break;
 353       case 'b': f |= f_buffer; break;
 354       case 'v': verb++; break;
 355       case 'q': if (verb) verb--; break;
 356       case 'C': f |= f_nocheck; break;
 357       case 'f': ef = optarg; break;
 358       case 'o': of = optarg; break;
 359       case 'p': f |= f_progress; break;
 360       default: f |= f_bogus; break;
 361     }
 362   }
 363   if (argc - optind > 1 || (f & f_bogus))
 364     die(EXIT_FAILURE, "Usage: decrypt [-OPTIONS] [FILE]");
 365
 366   if ((eo = getenc(ef)) == 0)
 367     die(EXIT_FAILURE, "encoding `%s' not found", ef);
 368
 369   fn = optind < argc ? argv[optind++] : "-";
 370   if (STRCMP(fn, ==, "-"))
 371     fp = stdin;
 372   else if ((fp = fopen(fn, eo->rmode)) == 0) {
 373     die(EXIT_FAILURE, "couldn't open file `%s': %s",
 374         fn, strerror(errno));
 375   }
 376
 377   if (key_open(&kf, keyring, KOPEN_READ, key_moan, 0))
 378     die(EXIT_FAILURE, "can't open keyring `%s'", keyring);
 379
 380   e = initdec(eo, fp, checkbdry, "CATCRYPT ENCRYPTED MESSAGE");
 381
 382   if (f & f_progress) {
 383     if (fprogress_init(&ff, fn, fp)) {
 384       die(EXIT_FAILURE, "failed to initialize progress display: %s",
 385           strerror(errno));
 386     }
 387   }
 388
 389   /* --- Read the header chunk --- */
 390
 391   chunk_read(e, &d, &b);
 392   if (f & f_progress)
 393     fprogress_update(&ff, BLEFT(&b)*e->ops->ncook/e->ops->nraw);
 394   if (buf_getu32(&b, &id)) {
 395     if (f & f_progress) fprogress_done(&ff);
 396     if (verb) printf("FAIL malformed header: missing keyid\n");
 397     exit(EXIT_FAILURE);
 398   }
 399   if ((k = key_byid(&kf, id)) == 0) {
 400     if (f & f_progress) fprogress_done(&ff);
 401     if (verb) printf("FAIL key id %08lx not found\n", (unsigned long)id);
 402     exit(EXIT_FAILURE);
 403   }
 404   if (BLEFT(&b)) {
 405     if (buf_getu32(&b, &id)) {
 406       if (f & f_progress) fprogress_done(&ff);
 407       if (verb) printf("FAIL malformed header: missing signature keyid\n");
 408       exit(EXIT_FAILURE);
 409     }
 410     if ((sk = key_byid(&kf, id)) == 0) {
 411       if (f & f_progress) fprogress_done(&ff);
 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 (f & f_progress) fprogress_done(&ff);
 418     if (verb) printf("FAIL malformed header: junk at end\n");
 419     exit(EXIT_FAILURE);
 420   }
 421   if (sk) {
 422     s = getsig(sk, "ccsig", 0);
 423     if (!(f & f_nocheck) && verb && (err = s->ops->check(s)) != 0) {
 424       dstr_reset(&d);
 425       key_fulltag(sk, &d);
 426       printf("WARN verification key %s fails check: %s\n", d.buf, err);
 427     }
 428     GH_HASHBUF16(s->h, BBASE(&b), BSZ(&b));
 429   }
 430
 431   /* --- Find the key --- */
 432
 433   km = getkem(k, "cckem", 1, &bc);
 434
 435   /* --- Read the KEM chunk --- */
 436
 437   chunk_read(e, &d, &b);
 438   if (f & f_progress)
 439     fprogress_update(&ff, BLEFT(&b)*e->ops->ncook/e->ops->nraw);
 440   if (setupkem(km, &d, bc)) {
 441     if (f & f_progress) fprogress_done(&ff);
 442     if (verb) printf("FAIL failed to decapsulate key\n");
 443     exit(EXIT_FAILURE);
 444   }
 445   if (s) GH_HASHBUF16(s->h, d.buf, d.len);
 446
 447   /* --- Verify the signature, if there is one --- */
 448
 449   if (sk) {
 450     dstr_reset(&d);
 451     dstr_ensure(&d, 1024);
 452     GC_ENCRYPT(km->cx, 0, d.buf, 1024);
 453     GH_HASH(s->h, d.buf, 1024);
 454     chunk_read(e, &d, &b);
 455     if (f & f_progress)
 456       fprogress_update(&ff, BLEFT(&b)*e->ops->ncook/e->ops->nraw);
 457     if (s->ops->doit(s, &d)) {
 458       if (f & f_progress) fprogress_done(&ff);
 459       if (verb) printf("FAIL signature verification failed\n");
 460       exit(EXIT_FAILURE);
 461     }
 462     if (verb) {
 463       dstr_reset(&d);
 464       key_fulltag(sk, &d);
 465       if (f & f_progress) fprogress_clear(&ff);
 466       printf("INFO good-signature %s\n", d.buf);
 467     }
 468     freesig(s);
 469   } else if (verb) {
 470     if (f & f_progress) fprogress_clear(&ff);
 471     printf("INFO no-signature\n");
 472   }
 473
 474   /* --- Now decrypt the main body --- */
 475
 476   if (!of || STRCMP(of, ==, "-")) {
 477     ofp = stdout;
 478     f |= f_buffer;
 479   }
 480   if (!(f & f_buffer)) {
 481     if ((ofp = fopen(of, "wb")) == 0) {
 482       if (f & f_progress) fprogress_done(&ff);
 483       die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 484           of, strerror(errno));
 485     }
 486     rfp = ofp;
 487   } else if ((rfp = tmpfile()) == 0) {
 488     if (f & f_progress) fprogress_done(&ff);
 489     die(EXIT_FAILURE, "couldn't create temporary file: %s", strerror(errno));
 490   }
 491
 492   seq = 0;
 493   dstr_ensure(&d, bc->ops->overhead(bc));
 494   dstr_ensure(&d, 4);
 495   for (;;) {
 496     chunk_read(e, &d, &b);
 497     if (f & f_progress)
 498       fprogress_update(&ff, BLEFT(&b)*e->ops->ncook/e->ops->nraw);
 499     buf_init(&b, bb, sizeof(bb));
 500     if ((err = bc->ops->doit(bc, seq, &b, d.buf, d.len)) != 0) {
 501       if (f & f_progress) fprogress_done(&ff);
 502       if (verb) printf("FAIL bad ciphertext chunk: %s\n", err);
 503       exit(EXIT_FAILURE);
 504     }
 505     seq++;
 506     if (!BLEN(&b)) break;
 507     if (fwrite(BBASE(&b), 1, BLEN(&b), rfp) != BLEN(&b)) {
 508       if (f & f_progress) fprogress_done(&ff);
 509       if (verb) printf("FAIL error writing output: %s\n", strerror(errno));
 510       exit(EXIT_FAILURE);
 511     }
 512   }
 513
 514   if (f & f_progress) fprogress_done(&ff);
 515   if (fflush(rfp) || ferror(rfp)) {
 516     if (verb) printf("FAIL error writing output: %s\n", strerror(errno));
 517     exit(EXIT_FAILURE);
 518   }
 519   if (f & f_buffer) {
 520     if (!ofp && (ofp = fopen(of, "wb")) == 0) {
 521       die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 522           of, strerror(errno));
 523     }
 524     rewind(rfp);
 525     if (f & f_progress) fprogress_init(&ff, "copying buffer", rfp);
 526     dstr_reset(&d);
 527     dstr_ensure(&d, 65536);
 528     if (verb && ofp == stdout) printf("DATA\n");
 529     for (;;) {
 530       n = fread(d.buf, 1, d.sz, rfp);
 531       if (!n) break;
 532       if (f & f_progress) fprogress_update(&ff, n);
 533       if (fwrite(d.buf, 1, n, ofp) < n) {
 534         if (f & f_progress) fprogress_done(&ff);
 535         die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
 536       }
 537     }
 538     if (f & f_progress) fprogress_done(&ff);
 539     if (ferror(rfp) || fclose(rfp))
 540       die(EXIT_FAILURE, "error unbuffering output: %s", strerror(errno));
 541   }
 542
 543   e->ops->decdone(e);
 544   if (verb && ofp != stdout)
 545     printf("OK decrypted successfully\n");
 546   if (ofp && (fflush(ofp) || ferror(ofp) || fclose(ofp)))
 547       die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
 548   bc->ops->destroy(bc);
 549   freeenc(e);
 550   freekem(km);
 551   if (fp != stdin) fclose(fp);
 552   key_close(&kf);
 553   dstr_destroy(&d);
 554   return (0);
 555
 556 #undef f_bogus
 557 #undef f_buffer
 558 #undef f_nocheck
 559 #undef f_progress
 560 }
 561
 562 /*----- Main code ---------------------------------------------------------*/
 563
 564 #define LISTS(LI)                                                       \
 565   LI("Lists", list,                                                     \
 566      listtab[i].name, listtab[i].name)                                  \
 567   LI("Key-encapsulation mechanisms", kem,                               \
 568      kemtab[i].name, kemtab[i].name)                                    \
 569   LI("Bulk crypto transforms", bulk,                                    \
 570      bulktab[i].name, bulktab[i].name)                                  \
 571   LI("Signature schemes", sig,                                          \
 572      sigtab[i].name, sigtab[i].name)                                    \
 573   LI("Encodings", enc,                                                  \
 574      enctab[i].name, enctab[i].name)                                    \
 575   LI("Symmetric encryption algorithms", cipher,                         \
 576      gciphertab[i], gciphertab[i]->name)                                \
 577   LI("Authenticated encryption schemes", aead,                          \
 578      gaeadtab[i], gaeadtab[i]->name)                                    \
 579   LI("Hash functions", hash,                                            \
 580      ghashtab[i], ghashtab[i]->name)                                    \
 581   LI("Message authentication codes", mac,                               \
 582      gmactab[i], gmactab[i]->name)
 583
 584 MAKELISTTAB(listtab, LISTS)
 585
 586 int cmd_show(int argc, char *argv[])
 587 {
 588   return (displaylists(listtab, argv + 1));
 589 }
 590
 591 static int cmd_help(int, char **);
 592
 593 static cmd cmdtab[] = {
 594   { "help", cmd_help, "help [COMMAND...]" },
 595   { "show", cmd_show, "show [ITEM...]" },
 596   CMD_ENCODE,
 597   CMD_DECODE,
 598   { "encrypt", encrypt,
 599     "encrypt [-apC] [-k TAG] [-s TAG] [-f FORMAT]\n\t\
 600 [-o OUTPUT] [FILE]", "\
 601 Options:\n\
 602 \n\
 603 -a, --armour            Same as `-f pem'.\n\
 604 -f, --format=FORMAT     Encode as FORMAT.\n\
 605 -k, --key=TAG           Use public encryption key named by TAG.\n\
 606 -s, --sign-key=TAG      Use private signature key named by TAG.\n\
 607 -o, --output=FILE       Write output to FILE.\n\
 608 -p, --progress          Show progress on large files.\n\
 609 -C, --nocheck           Don't check the public key.\n\
 610 " },
 611   { "decrypt", decrypt,
 612     "decrypt [-abpqvC] [-f FORMAT] [-o OUTPUT] [FILE]", "\
 613 Options:\n\
 614 \n\
 615 -a, --armour            Same as `-f pem'.\n\
 616 -b, --buffer            Buffer output until we're sure we have it all.\n\
 617 -f, --format=FORMAT     Decode as FORMAT.\n\
 618 -o, --output=FILE       Write output to FILE.\n\
 619 -p, --progress          Show progress on large files.\n\
 620 -q, --quiet             Produce fewer messages.\n\
 621 -v, --verbose           Produce more verbose messages.\n\
 622 -C, --nocheck           Don't check the private key.\n\
 623 " },
 624   { 0, 0, 0 }
 625 };
 626
 627 static int cmd_help(int argc, char **argv)
 628 {
 629   sc_help(cmdtab, stdout, argv + 1);
 630   return (0);
 631 }
 632
 633 void version(FILE *fp)
 634 {
 635   pquis(fp, "$, Catacomb version " VERSION "\n");
 636 }
 637
 638 static void usage(FILE *fp)
 639 {
 640   pquis(fp, "Usage: $ [-k KEYRING] COMMAND [ARGS]\n");
 641 }
 642
 643 void help_global(FILE *fp)
 644 {
 645   usage(fp);
 646   fputs("\n\
 647 Encrypt and decrypt files.\n\
 648 \n\
 649 Global command-line options:\n\
 650 \n\
 651 -h, --help [COMMAND...] Show this help message, or help for COMMANDs.\n\
 652 -v, --version           Show program version number.\n\
 653 -u, --usage             Show a terse usage message.\n\
 654 \n\
 655 -k, --keyring=FILE      Read keys from FILE.\n",
 656         fp);
 657 }
 658
 659 /* --- @main@ --- *
 660  *
 661  * Arguments:   @int argc@ = number of command line arguments
 662  *              @char *argv[]@ = vector of command line arguments
 663  *
 664  * Returns:     Zero if successful, nonzero otherwise.
 665  *
 666  * Use:         Encrypts or decrypts files.
 667  */
 668
 669 int main(int argc, char *argv[])
 670 {
 671   unsigned f = 0;
 672
 673 #define f_bogus 1u
 674
 675   /* --- Initialize the library --- */
 676
 677   ego(argv[0]);
 678   sub_init();
 679   rand_noisesrc(RAND_GLOBAL, &noise_source);
 680   rand_seed(RAND_GLOBAL, 160);
 681
 682   /* --- Parse options --- */
 683
 684   for (;;) {
 685     static struct option opts[] = {
 686       { "help",         0,              0,      'h' },
 687       { "version",      0,              0,      'v' },
 688       { "usage",        0,              0,      'u' },
 689       { "keyring",      OPTF_ARGREQ,    0,      'k' },
 690       { 0,              0,              0,      0 }
 691     };
 692     int i = mdwopt(argc, argv, "+hvu k:", opts, 0, 0, 0);
 693     if (i < 0)
 694       break;
 695     switch (i) {
 696       case 'h':
 697         sc_help(cmdtab, stdout, argv + optind);
 698         exit(0);
 699         break;
 700       case 'v':
 701         version(stdout);
 702         exit(0);
 703         break;
 704       case 'u':
 705         usage(stdout);
 706         exit(0);
 707       case 'k':
 708         keyring = optarg;
 709         break;
 710       default:
 711         f |= f_bogus;
 712         break;
 713     }
 714   }
 715
 716   argc -= optind;
 717   argv += optind;
 718   optind = 0;
 719   if (f & f_bogus || argc < 1) {
 720     usage(stderr);
 721     exit(EXIT_FAILURE);
 722   }
 723
 724   /* --- Dispatch to the correct subcommand handler --- */
 725
 726   return (findcmd(cmdtab, argv[0])->cmd(argc, argv));
 727
 728 #undef f_bogus
 729 }
 730
 731 /*----- That's all, folks -------------------------------------------------*/