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/mdwopt.h>
  42 #include <mLib/quis.h>
  43 #include <mLib/report.h>
  44 #include <mLib/sub.h>
  45
  46 #include "buf.h"
  47 #include "ct.h"
  48 #include "rand.h"
  49 #include "noise.h"
  50 #include "mprand.h"
  51 #include "key.h"
  52 #include "cc.h"
  53
  54 #include "ectab.h"
  55 #include "ptab.h"
  56
  57 /*----- Static variables --------------------------------------------------*/
  58
  59 static const char *keyring = "keyring";
  60
  61 /*----- Data format -------------------------------------------------------*/
  62
  63 /* --- Overview --- *
  64  *
  65  * The encrypted message is divided into chunks, each preceded by a two-octet
  66  * length.  The chunks don't need to be large -- the idea is that we can
  67  * stream the chunks in and out.
  68  *
  69  * The first chunk is a header.  It contains the decryption key-id, and maybe
  70  * the verification key-id if the message is signed.
  71  *
  72  * Next comes the key-encapsulation chunk.  This is decrypted in some
  73  * KEM-specific way to yield a secret hash.  The hash is expanded using an
  74  * MGF (or similar) to make a symmetric encryption and MAC key.
  75  *
  76  * If the message is signed, there comes a signature chunk.  The signature is
  77  * on the header and key-encapsulation chunks, and further output of the MGF.
  78  * This means that the recipient can modify the message and still have a
  79  * valid signature, so it's not useful for proving things to other people;
  80  * but it also means that the recipient knows that the message is from
  81  * someone who knows the hash, which limits the possiblities to (a) whoever
  82  * encrypted the message (good!) and (b) whoever knows the recipient's
  83  * private key.
  84  *
  85  * Then come message chunks.  Each one begins with a MAC over an implicit
  86  * sequence number and the ciphertext.  The final chunk's ciphertext is
  87  * empty; no other chunk is empty.  Thus can the correct end-of-file be
  88  * discerned.
  89  */
  90
  91 /*----- Chunk I/O ---------------------------------------------------------*/
  92
  93 static void chunk_write(enc *e, buf *b)
  94 {
  95   octet l[2];
  96   size_t n = BLEN(b);
  97   assert(n <= MASK16);
  98   STORE16(l, n);
  99   if (e->ops->write(e, l, 2) ||
 100       e->ops->write(e, BBASE(b), BLEN(b)))
 101     die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
 102 }
 103
 104 static void chunk_read(enc *e, dstr *d, buf *b)
 105 {
 106   octet l[2];
 107   size_t n;
 108
 109   dstr_reset(d);
 110   errno = 0;
 111   if (e->ops->read(e, l, 2) != 2)
 112     goto err;
 113   n = LOAD16(l);
 114   dstr_ensure(d, n);
 115   if (e->ops->read(e, d->buf, n) != n)
 116     goto err;
 117   d->len = n;
 118   buf_init(b, d->buf, d->len);
 119   return;
 120
 121 err:
 122   if (!errno) die(EXIT_FAILURE, "unexpected end-of-file on input");
 123   else die(EXIT_FAILURE, "error reading input: %s", strerror(errno));
 124 }
 125
 126 /*----- Encryption --------------------------------------------------------*/
 127
 128 static int encrypt(int argc, char *argv[])
 129 {
 130   const char *fn, *of = 0, *kn = "ccrypt", *skn = 0;
 131   FILE *ofp = 0;
 132   FILE *fp = 0;
 133   const char *ef = "binary";
 134   fprogress ff;
 135   const char *err;
 136   int i;
 137   int en;
 138   size_t n, chsz;
 139   dstr d = DSTR_INIT;
 140   octet *tag, *ct;
 141   buf b;
 142   size_t seq;
 143   char bb[65536];
 144   unsigned f = 0;
 145   key_file kf;
 146   key *k;
 147   key *sk = 0;
 148   kem *km;
 149   sig *s = 0;
 150   gcipher *cx, *c;
 151   gmac *m;
 152   ghash *h;
 153   const encops *eo;
 154   enc *e;
 155
 156 #define f_bogus 1u
 157 #define f_nocheck 2u
 158 #define f_progress 4u
 159
 160   for (;;) {
 161     static const struct option opt[] = {
 162       { "key",          OPTF_ARGREQ,    0,      'k' },
 163       { "sign-key",     OPTF_ARGREQ,    0,      's' },
 164       { "armour",       0,              0,      'a' },
 165       { "armor",        0,              0,      'a' },
 166       { "format",       OPTF_ARGREQ,    0,      'f' },
 167       { "output",       OPTF_ARGREQ,    0,      'o' },
 168       { "progress",     0,              0,      'p' },
 169       { "nocheck",      0,              0,      'C' },
 170       { 0,              0,              0,      0 }
 171     };
 172     i = mdwopt(argc, argv, "k:s:af:o:pC", opt, 0, 0, 0);
 173     if (i < 0) break;
 174     switch (i) {
 175       case 'k': kn = optarg; break;
 176       case 's': skn = optarg; break;
 177       case 'a': ef = "pem"; break;
 178       case 'f': ef = optarg; break;
 179       case 'o': of = optarg; break;
 180       case 'p': f |= f_progress; break;
 181       case 'C': f |= f_nocheck; break;
 182       default: f |= f_bogus; break;
 183     }
 184   }
 185   if (argc - optind > 1 || (f & f_bogus))
 186     die(EXIT_FAILURE, "Usage: encrypt [-OPTIONS] [FILE]");
 187
 188   if (key_open(&kf, keyring, KOPEN_READ, key_moan, 0))
 189     die(EXIT_FAILURE, "can't open keyring `%s'", keyring);
 190   if ((k = key_bytag(&kf, kn)) == 0)
 191     die(EXIT_FAILURE, "key `%s' not found", kn);
 192   if (skn && (sk = key_bytag(&kf, skn)) == 0)
 193     die(EXIT_FAILURE, "key `%s' not found", skn);
 194
 195   if ((eo = getenc(ef)) == 0)
 196     die(EXIT_FAILURE, "encoding `%s' not found", ef);
 197
 198   fn = optind < argc ? argv[optind++] : "-";
 199   if (strcmp(fn, "-") == 0)
 200     fp = stdin;
 201   else if ((fp = fopen(fn, "rb")) == 0) {
 202     die(EXIT_FAILURE, "couldn't open file `%s': %s",
 203         fn, strerror(errno));
 204   }
 205
 206   if (!of || strcmp(of, "-") == 0)
 207     ofp = stdout;
 208   else if ((ofp = fopen(of, eo->wmode)) == 0) {
 209     die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 210         of, strerror(errno));
 211   }
 212
 213   dstr_reset(&d);
 214   key_fulltag(k, &d);
 215   e = initenc(eo, ofp, "CATCRYPT ENCRYPTED MESSAGE");
 216   km = getkem(k, "cckem", 0);
 217   if (!(f & f_nocheck) && (err = km->ops->check(km)) != 0)
 218     moan("key %s fails check: %s", d.buf, err);
 219   if (sk) {
 220     dstr_reset(&d);
 221     key_fulltag(sk, &d);
 222     s = getsig(sk, "ccsig", 1);
 223     if ((err = s->ops->check(s)) != 0)
 224       moan("key %s fails check: %s", d.buf, err);
 225   }
 226
 227   /* --- Build the header chunk --- */
 228
 229   dstr_reset(&d);
 230   dstr_ensure(&d, 256);
 231   buf_init(&b, d.buf, 256);
 232   buf_putu32(&b, k->id);
 233   if (sk) buf_putu32(&b, sk->id);
 234   assert(BOK(&b));
 235   if (s) GH_HASHBUF16(s->h, BBASE(&b), BLEN(&b));
 236   chunk_write(e, &b);
 237
 238   /* --- Build the KEM chunk --- */
 239
 240   dstr_reset(&d);
 241   if (setupkem(km, &d, &cx, &c, &m))
 242     die(EXIT_FAILURE, "failed to encapsulate key");
 243   buf_init(&b, d.buf, d.len);
 244   BSTEP(&b, d.len);
 245   if (s) GH_HASHBUF16(s->h, BBASE(&b), BLEN(&b));
 246   chunk_write(e, &b);
 247
 248   /* --- Write the signature chunk --- */
 249
 250   if (s) {
 251     GC_ENCRYPT(cx, 0, bb, 1024);
 252     GH_HASH(s->h, bb, 1024);
 253     dstr_reset(&d);
 254     if ((en = s->ops->doit(s, &d)) != 0)
 255       die(EXIT_FAILURE, "error creating signature: %s", key_strerror(en));
 256     buf_init(&b, d.buf, d.len);
 257     BSTEP(&b, d.len);
 258     chunk_write(e, &b);
 259   }
 260
 261   /* --- Now do the main crypto --- */
 262
 263   if (f & f_progress) {
 264     if (fprogress_init(&ff, fn, fp)) {
 265       die(EXIT_FAILURE, "failed to initialize progress display: %s",
 266           strerror(errno));
 267     }
 268   }
 269
 270   assert(GC_CLASS(c)->blksz <= sizeof(bb));
 271   dstr_ensure(&d, sizeof(bb) + GM_CLASS(m)->hashsz);
 272   seq = 0;
 273   chsz = MASK16 - GM_CLASS(m)->hashsz;
 274   for (;;) {
 275     h = GM_INIT(m);
 276     GH_HASHU32(h, seq);
 277     seq++;
 278     if (GC_CLASS(c)->blksz) {
 279       GC_ENCRYPT(cx, 0, bb, GC_CLASS(c)->blksz);
 280       GC_SETIV(c, bb);
 281     }
 282     n = fread(bb, 1, chsz, fp);
 283     if (!n) break;
 284     if (f & f_progress) fprogress_update(&ff, n);
 285     buf_init(&b, d.buf, d.sz);
 286     tag = buf_get(&b, GM_CLASS(m)->hashsz);
 287     ct = buf_get(&b, n);
 288     assert(tag); assert(ct);
 289     GC_ENCRYPT(c, bb, ct, n);
 290     GH_HASH(h, ct, n);
 291     GH_DONE(h, tag);
 292     GH_DESTROY(h);
 293     chunk_write(e, &b);
 294   }
 295
 296   /* --- Final terminator packet --- */
 297
 298   buf_init(&b, d.buf, d.sz);
 299   tag = buf_get(&b, GM_CLASS(m)->hashsz);
 300   assert(tag);
 301   GH_DONE(h, tag);
 302   GH_DESTROY(h);
 303   chunk_write(e, &b);
 304
 305   /* --- All done --- */
 306
 307   if (f & f_progress) fprogress_done(&ff);
 308   e->ops->encdone(e);
 309   GM_DESTROY(m);
 310   GC_DESTROY(c);
 311   GC_DESTROY(cx);
 312   freeenc(e);
 313   if (s) freesig(s);
 314   freekem(km);
 315   if (fp != stdin) fclose(fp);
 316   if (of) fclose(ofp);
 317   key_close(&kf);
 318   dstr_destroy(&d);
 319   return (0);
 320
 321 #undef f_bogus
 322 #undef f_nocheck
 323 #undef f_progress
 324 }
 325
 326 /*---- Decryption ---------------------------------------------------------*/
 327
 328 static int decrypt(int argc, char *argv[])
 329 {
 330   const char *fn, *of = 0;
 331   FILE *ofp = 0, *rfp = 0;
 332   FILE *fp = 0;
 333   const char *ef = "binary";
 334   fprogress ff;
 335   int i;
 336   size_t n;
 337   dstr d = DSTR_INIT;
 338   buf b;
 339   key_file kf;
 340   size_t seq;
 341   uint32 id;
 342   key *k;
 343   key *sk = 0;
 344   kem *km;
 345   sig *s = 0;
 346   gcipher *cx;
 347   gcipher *c;
 348   ghash *h;
 349   gmac *m;
 350   octet *tag;
 351   unsigned f = 0;
 352   const encops *eo;
 353   const char *err;
 354   int verb = 1;
 355   enc *e;
 356
 357 #define f_bogus 1u
 358 #define f_buffer 2u
 359 #define f_nocheck 4u
 360 #define f_progress 8u
 361
 362   for (;;) {
 363     static const struct option opt[] = {
 364       { "armour",       0,              0,      'a' },
 365       { "armor",        0,              0,      'a' },
 366       { "buffer",       0,              0,      'b' },
 367       { "verbose",      0,              0,      'v' },
 368       { "quiet",        0,              0,      'q' },
 369       { "nocheck",      0,              0,      'C' },
 370       { "format",       OPTF_ARGREQ,    0,      'f' },
 371       { "output",       OPTF_ARGREQ,    0,      'o' },
 372       { "progress",     0,              0,      'p' },
 373       { 0,              0,              0,      0 }
 374     };
 375     i = mdwopt(argc, argv, "abf:o:pqvC", opt, 0, 0, 0);
 376     if (i < 0) break;
 377     switch (i) {
 378       case 'a': ef = "pem"; break;
 379       case 'b': f |= f_buffer; break;
 380       case 'v': verb++; break;
 381       case 'q': if (verb) verb--; break;
 382       case 'C': f |= f_nocheck; break;
 383       case 'f': ef = optarg; break;
 384       case 'o': of = optarg; break;
 385       case 'p': f |= f_progress; break;
 386       default: f |= f_bogus; break;
 387     }
 388   }
 389   if (argc - optind > 1 || (f & f_bogus))
 390     die(EXIT_FAILURE, "Usage: decrypt [-OPTIONS] [FILE]");
 391
 392   if ((eo = getenc(ef)) == 0)
 393     die(EXIT_FAILURE, "encoding `%s' not found", ef);
 394
 395   fn = optind < argc ? argv[optind++] : "-";
 396   if (strcmp(fn, "-") == 0)
 397     fp = stdin;
 398   else if ((fp = fopen(fn, eo->rmode)) == 0) {
 399     die(EXIT_FAILURE, "couldn't open file `%s': %s",
 400         fn, strerror(errno));
 401   }
 402
 403   if (key_open(&kf, keyring, KOPEN_READ, key_moan, 0))
 404     die(EXIT_FAILURE, "can't open keyring `%s'", keyring);
 405
 406   e = initdec(eo, fp, checkbdry, "CATCRYPT ENCRYPTED MESSAGE");
 407
 408   if (f & f_progress) {
 409     if (fprogress_init(&ff, fn, fp)) {
 410       die(EXIT_FAILURE, "failed to initialize progress display: %s",
 411           strerror(errno));
 412     }
 413   }
 414
 415   /* --- Read the header chunk --- */
 416
 417   chunk_read(e, &d, &b);
 418   if (f & f_progress)
 419     fprogress_update(&ff, BLEFT(&b)*e->ops->ncook/e->ops->nraw);
 420   if (buf_getu32(&b, &id)) {
 421     if (f & f_progress) fprogress_done(&ff);
 422     if (verb) printf("FAIL malformed header: missing keyid\n");
 423     exit(EXIT_FAILURE);
 424   }
 425   if ((k = key_byid(&kf, id)) == 0) {
 426     if (f & f_progress) fprogress_done(&ff);
 427     if (verb) printf("FAIL key id %08lx not found\n", (unsigned long)id);
 428     exit(EXIT_FAILURE);
 429   }
 430   if (BLEFT(&b)) {
 431     if (buf_getu32(&b, &id)) {
 432       if (f & f_progress) fprogress_done(&ff);
 433       if (verb) printf("FAIL malformed header: missing signature keyid\n");
 434       exit(EXIT_FAILURE);
 435     }
 436     if ((sk = key_byid(&kf, id)) == 0) {
 437       if (f & f_progress) fprogress_done(&ff);
 438       if (verb) printf("FAIL key id %08lx not found\n", (unsigned long)id);
 439       exit(EXIT_FAILURE);
 440     }
 441   }
 442   if (BLEFT(&b)) {
 443     if (f & f_progress) fprogress_done(&ff);
 444     if (verb) printf("FAIL malformed header: junk at end\n");
 445     exit(EXIT_FAILURE);
 446   }
 447   if (sk) {
 448     s = getsig(sk, "ccsig", 0);
 449     if (!(f & f_nocheck) && verb && (err = s->ops->check(s)) != 0) {
 450       dstr_reset(&d);
 451       key_fulltag(sk, &d);
 452       printf("WARN verification key %s fails check: %s\n", d.buf, err);
 453     }
 454     GH_HASHBUF16(s->h, BBASE(&b), BSZ(&b));
 455   }
 456
 457   /* --- Find the key --- */
 458
 459   km = getkem(k, "cckem", 1);
 460
 461   /* --- Read the KEM chunk --- */
 462
 463   chunk_read(e, &d, &b);
 464   if (f & f_progress)
 465     fprogress_update(&ff, BLEFT(&b)*e->ops->ncook/e->ops->nraw);
 466   if (setupkem(km, &d, &cx, &c, &m)) {
 467     if (f & f_progress) fprogress_done(&ff);
 468     if (verb) printf("FAIL failed to decapsulate key\n");
 469     exit(EXIT_FAILURE);
 470   }
 471   if (s) GH_HASHBUF16(s->h, d.buf, d.len);
 472
 473   /* --- Verify the signature, if there is one --- */
 474
 475   if (sk) {
 476     dstr_reset(&d);
 477     dstr_ensure(&d, 1024);
 478     GC_ENCRYPT(cx, 0, d.buf, 1024);
 479     GH_HASH(s->h, d.buf, 1024);
 480     chunk_read(e, &d, &b);
 481     if (f & f_progress)
 482       fprogress_update(&ff, BLEFT(&b)*e->ops->ncook/e->ops->nraw);
 483     if (s->ops->doit(s, &d)) {
 484       if (f & f_progress) fprogress_done(&ff);
 485       if (verb) printf("FAIL signature verification failed\n");
 486       exit(EXIT_FAILURE);
 487     }
 488     if (verb) {
 489       dstr_reset(&d);
 490       key_fulltag(sk, &d);
 491       if (f & f_progress) fprogress_clear(&ff);
 492       printf("INFO good-signature %s\n", d.buf);
 493     }
 494     freesig(s);
 495   } else if (verb) {
 496     if (f & f_progress) fprogress_clear(&ff);
 497     printf("INFO no-signature\n");
 498   }
 499
 500   /* --- Now decrypt the main body --- */
 501
 502   if (!of || strcmp(of, "-") == 0) {
 503     ofp = stdout;
 504     f |= f_buffer;
 505   }
 506   if (!(f & f_buffer)) {
 507     if ((ofp = fopen(of, "wb")) == 0) {
 508       if (f & f_progress) fprogress_done(&ff);
 509       die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 510           of, strerror(errno));
 511     }
 512     rfp = ofp;
 513   } else if ((rfp = tmpfile()) == 0) {
 514     if (f & f_progress) fprogress_done(&ff);
 515     die(EXIT_FAILURE, "couldn't create temporary file: %s", strerror(errno));
 516   }
 517
 518   seq = 0;
 519   dstr_ensure(&d, GC_CLASS(c)->blksz);
 520   dstr_ensure(&d, 4);
 521   for (;;) {
 522     if (GC_CLASS(c)->blksz) {
 523       GC_ENCRYPT(cx, 0, d.buf, GC_CLASS(c)->blksz);
 524       GC_SETIV(c, d.buf);
 525     }
 526     h = GM_INIT(m);
 527     GH_HASHU32(h, seq);
 528     seq++;
 529     chunk_read(e, &d, &b);
 530     if (f & f_progress)
 531       fprogress_update(&ff, BLEFT(&b)*e->ops->ncook/e->ops->nraw);
 532     if ((tag = buf_get(&b, GM_CLASS(m)->hashsz)) == 0) {
 533       if (f & f_progress) fprogress_done(&ff);
 534       if (verb) printf("FAIL bad ciphertext chunk: no tag\n");
 535       exit(EXIT_FAILURE);
 536     }
 537     GH_HASH(h, BCUR(&b), BLEFT(&b));
 538     if (!ct_memeq(tag, GH_DONE(h, 0), GM_CLASS(m)->hashsz)) {
 539       if (f & f_progress) fprogress_done(&ff);
 540       if (verb)
 541         printf("FAIL bad ciphertext chunk: authentication failure\n");
 542       exit(EXIT_FAILURE);
 543     }
 544     GH_DESTROY(h);
 545     if (!BLEFT(&b))
 546       break;
 547     GC_DECRYPT(c, BCUR(&b), BCUR(&b), BLEFT(&b));
 548     if (fwrite(BCUR(&b), 1, BLEFT(&b), rfp) != BLEFT(&b)) {
 549       if (f & f_progress) fprogress_done(&ff);
 550       if (verb) printf("FAIL error writing output: %s\n", strerror(errno));
 551       exit(EXIT_FAILURE);
 552     }
 553   }
 554
 555   if (f & f_progress) fprogress_done(&ff);
 556   if (fflush(rfp) || ferror(rfp)) {
 557     if (verb) printf("FAIL error writing output: %s\n", strerror(errno));
 558     exit(EXIT_FAILURE);
 559   }
 560   if (f & f_buffer) {
 561     if (!ofp && (ofp = fopen(of, "wb")) == 0) {
 562       die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 563           of, strerror(errno));
 564     }
 565     rewind(rfp);
 566     if (f & f_progress) fprogress_init(&ff, "copying buffer", rfp);
 567     dstr_reset(&d);
 568     dstr_ensure(&d, 65536);
 569     if (verb && ofp == stdout) printf("DATA\n");
 570     for (;;) {
 571       n = fread(d.buf, 1, d.sz, rfp);
 572       if (!n) break;
 573       if (f & f_progress) fprogress_update(&ff, n);
 574       if (fwrite(d.buf, 1, n, ofp) < n) {
 575         if (f & f_progress) fprogress_done(&ff);
 576         die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
 577       }
 578     }
 579     if (f & f_progress) fprogress_done(&ff);
 580     if (ferror(rfp) || fclose(rfp))
 581       die(EXIT_FAILURE, "error unbuffering output: %s", strerror(errno));
 582   }
 583
 584   e->ops->decdone(e);
 585   if (verb && ofp != stdout)
 586     printf("OK decrypted successfully\n");
 587   if (ofp && (fflush(ofp) || ferror(ofp) || fclose(ofp)))
 588       die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
 589   freeenc(e);
 590   GC_DESTROY(c);
 591   GC_DESTROY(cx);
 592   GM_DESTROY(m);
 593   freekem(km);
 594   if (fp != stdin) fclose(fp);
 595   key_close(&kf);
 596   dstr_destroy(&d);
 597   return (0);
 598
 599 #undef f_bogus
 600 #undef f_buffer
 601 #undef f_nocheck
 602 #undef f_progress
 603 }
 604
 605 /*----- Main code ---------------------------------------------------------*/
 606
 607 #define LISTS(LI)                                                       \
 608   LI("Lists", list,                                                     \
 609      listtab[i].name, listtab[i].name)                                  \
 610   LI("Key-encapsulation mechanisms", kem,                               \
 611      kemtab[i].name, kemtab[i].name)                                    \
 612   LI("Signature schemes", sig,                                          \
 613      sigtab[i].name, sigtab[i].name)                                    \
 614   LI("Encodings", enc,                                                  \
 615      enctab[i].name, enctab[i].name)                                    \
 616   LI("Symmetric encryption algorithms", cipher,                         \
 617      gciphertab[i], gciphertab[i]->name)                                \
 618   LI("Hash functions", hash,                                            \
 619      ghashtab[i], ghashtab[i]->name)                                    \
 620   LI("Message authentication codes", mac,                               \
 621      gmactab[i], gmactab[i]->name)
 622
 623 MAKELISTTAB(listtab, LISTS)
 624
 625 int cmd_show(int argc, char *argv[])
 626 {
 627   return (displaylists(listtab, argv + 1));
 628 }
 629
 630 static int cmd_help(int, char **);
 631
 632 static cmd cmdtab[] = {
 633   { "help", cmd_help, "help [COMMAND...]" },
 634   { "show", cmd_show, "show [ITEM...]" },
 635   CMD_ENCODE,
 636   CMD_DECODE,
 637   { "encrypt", encrypt,
 638     "encrypt [-apC] [-k TAG] [-s TAG] [-f FORMAT]\n\t\
 639 [-o OUTPUT] [FILE]", "\
 640 Options:\n\
 641 \n\
 642 -a, --armour            Same as `-f pem'.\n\
 643 -f, --format=FORMAT     Encode as FORMAT.\n\
 644 -k, --key=TAG           Use public encryption key named by TAG.\n\
 645 -s, --sign-key=TAG      Use private signature key named by TAG.\n\
 646 -o, --output=FILE       Write output to FILE.\n\
 647 -p, --progress          Show progress on large files.\n\
 648 -C, --nocheck           Don't check the public key.\n\
 649 " },
 650   { "decrypt", decrypt,
 651     "decrypt [-abpqvC] [-f FORMAT] [-o OUTPUT] [FILE]", "\
 652 Options:\n\
 653 \n\
 654 -a, --armour            Same as `-f pem'.\n\
 655 -b, --buffer            Buffer output until we're sure we have it all.\n\
 656 -f, --format=FORMAT     Decode as FORMAT.\n\
 657 -o, --output=FILE       Write output to FILE.\n\
 658 -p, --progress          Show progress on large files.\n\
 659 -q, --quiet             Produce fewer messages.\n\
 660 -v, --verbose           Produce more verbose messages.\n\
 661 -C, --nocheck           Don't check the private key.\n\
 662 " },
 663   { 0, 0, 0 }
 664 };
 665
 666 static int cmd_help(int argc, char **argv)
 667 {
 668   sc_help(cmdtab, stdout, argv + 1);
 669   return (0);
 670 }
 671
 672 void version(FILE *fp)
 673 {
 674   pquis(fp, "$, Catacomb version " VERSION "\n");
 675 }
 676
 677 static void usage(FILE *fp)
 678 {
 679   pquis(fp, "Usage: $ [-k KEYRING] COMMAND [ARGS]\n");
 680 }
 681
 682 void help_global(FILE *fp)
 683 {
 684   usage(fp);
 685   fputs("\n\
 686 Encrypt and decrypt files.\n\
 687 \n\
 688 Global command-line options:\n\
 689 \n\
 690 -h, --help [COMMAND...] Show this help message, or help for COMMANDs.\n\
 691 -v, --version           Show program version number.\n\
 692 -u, --usage             Show a terse usage message.\n\
 693 \n\
 694 -k, --keyring=FILE      Read keys from FILE.\n",
 695         fp);
 696 }
 697
 698 /* --- @main@ --- *
 699  *
 700  * Arguments:   @int argc@ = number of command line arguments
 701  *              @char *argv[]@ = vector of command line arguments
 702  *
 703  * Returns:     Zero if successful, nonzero otherwise.
 704  *
 705  * Use:         Encrypts or decrypts files.
 706  */
 707
 708 int main(int argc, char *argv[])
 709 {
 710   unsigned f = 0;
 711
 712 #define f_bogus 1u
 713
 714   /* --- Initialize the library --- */
 715
 716   ego(argv[0]);
 717   sub_init();
 718   rand_noisesrc(RAND_GLOBAL, &noise_source);
 719   rand_seed(RAND_GLOBAL, 160);
 720
 721   /* --- Parse options --- */
 722
 723   for (;;) {
 724     static struct option opts[] = {
 725       { "help",         0,              0,      'h' },
 726       { "version",      0,              0,      'v' },
 727       { "usage",        0,              0,      'u' },
 728       { "keyring",      OPTF_ARGREQ,    0,      'k' },
 729       { 0,              0,              0,      0 }
 730     };
 731     int i = mdwopt(argc, argv, "+hvu k:", opts, 0, 0, 0);
 732     if (i < 0)
 733       break;
 734     switch (i) {
 735       case 'h':
 736         sc_help(cmdtab, stdout, argv + optind);
 737         exit(0);
 738         break;
 739       case 'v':
 740         version(stdout);
 741         exit(0);
 742         break;
 743       case 'u':
 744         usage(stdout);
 745         exit(0);
 746       case 'k':
 747         keyring = optarg;
 748         break;
 749       default:
 750         f |= f_bogus;
 751         break;
 752     }
 753   }
 754
 755   argc -= optind;
 756   argv += optind;
 757   optind = 0;
 758   if (f & f_bogus || argc < 1) {
 759     usage(stderr);
 760     exit(EXIT_FAILURE);
 761   }
 762
 763   /* --- Dispatch to the correct subcommand handler --- */
 764
 765   return (findcmd(cmdtab, argv[0])->cmd(argc, argv));
 766
 767 #undef f_bogus
 768 }
 769
 770 /*----- That's all, folks -------------------------------------------------*/