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

   1 /* -*-c-*-
   2  *
   3  * Sign files
   4  *
   5  * (c) 2005 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 <ctype.h>
  35 #include <errno.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <time.h>
  40
  41 #include <mLib/base64.h>
  42 #include <mLib/dstr.h>
  43 #include <mLib/macros.h>
  44 #include <mLib/mdwopt.h>
  45 #include <mLib/quis.h>
  46 #include <mLib/report.h>
  47 #include <mLib/sub.h>
  48
  49 #include "buf.h"
  50 #include "rand.h"
  51 #include "noise.h"
  52 #include "mprand.h"
  53 #include "key.h"
  54 #include "getdate.h"
  55 #include "cc.h"
  56
  57 #include "ectab.h"
  58 #include "ptab.h"
  59
  60 /*----- Static variables --------------------------------------------------*/
  61
  62 static const char *keyring = "keyring";
  63
  64 /*----- Data formats ------------------------------------------------------*
  65  *
  66  * Our crypto stuff is split into three parts: a header describing the key,
  67  * the message itself, and the signature.  In a detached signature, the
  68  * message is separate, and the header and signature are combined into one
  69  * encoded chunk.  In an attached signature, the message is included.  There
  70  * are two forms of message: binary and text.  Binary messages are divided
  71  * into chunks, each preceded by a 2-octet length, and terminated by a
  72  * zero-length chunk.  Text messages are byte-stuffed, as for RFC821, and
  73  * trailing whitespace before a newline is ignored.
  74  */
  75
  76 typedef struct sigmsg {
  77   unsigned f;                           /* Flags */
  78 #define F_DETACH 1u
  79 #define F_BINARY 2u
  80 #define F_SIGMASK 3u
  81 #define F_HASHMASK (F_BINARY)
  82   uint32 keyid;                         /* Key identifier */
  83   time_t t;                             /* When the signature was made */
  84   dstr kh;                              /* Key fingerprint (sanity check) */
  85   dstr sig;                             /* Signature */
  86   sig *s;                               /* Signature algorithm */
  87 } sigmsg;
  88
  89 #define F_MIDLINE 16u
  90 #define F_EOF 32u
  91 #define F_NOCLOSE 64u
  92 #define F_BOGUS 128u
  93 #define F_BUFFER 256u
  94 #define F_UTC 512u
  95 #define F_NOCHECK 1024u
  96 #define F_PROGRESS 2048u
  97
  98 /*----- Chunk I/O ---------------------------------------------------------*/
  99
 100 static void chunk_write(enc *e, const void *p, size_t n)
 101 {
 102   octet b[2];
 103
 104   assert(n <= 0xffff);
 105   STORE16(b, n);
 106   if (e->ops->write(e, b, 2) || e->ops->write(e, p, n))
 107     die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
 108 }
 109
 110 static size_t chunk_read(enc *e, void *p)
 111 {
 112   octet b[2];
 113   size_t n;
 114
 115   if (e->ops->read(e, b, 2) != 2)
 116     goto err;
 117   n = LOAD16(b);
 118   if (n && e->ops->read(e, p, n) != n)
 119     goto err;
 120   return (n);
 121
 122 err:
 123   if (!errno) die(EXIT_FAILURE, "unexpected end-of-file on input");
 124   else die(EXIT_FAILURE, "error reading input: %s", strerror(errno));
 125   return (0);
 126 }
 127
 128 /*----- Message canonification --------------------------------------------*/
 129
 130 #define MSGBUFSZ 65536
 131 #define MSGBUFTHRESH 32768
 132
 133 typedef struct msgcanon {
 134   unsigned f;
 135   FILE *fp;
 136   enc *e;
 137   fprogress ff;
 138   size_t (*read)(struct msgcanon *, void *);
 139   void (*write)(struct msgcanon *, const void *, size_t);
 140   void (*close)(struct msgcanon *);
 141 } msgcanon;
 142
 143 #define MC_INIT { 0 }
 144
 145 static size_t textread(msgcanon *m, void *bp)
 146 {
 147   size_t n = 0, nsp = 0;
 148   int ch;
 149   char *b = bp;
 150   unsigned f = m->f;
 151
 152   if (f & F_EOF) return (0);
 153   for (;;) {
 154     if ((ch = getc(m->fp)) == EOF) goto eof;
 155     if (!(f & (F_DETACH | F_MIDLINE)) && ch == '.') {
 156       ch = getc(m->fp);
 157       if (ch == '\n') goto eof;
 158     }
 159     if (ch == '\n') {
 160       n -= nsp; nsp = 0;
 161       if (n >= MSGBUFTHRESH) goto full;
 162       b[n++] = ch;
 163       f &= ~F_MIDLINE;
 164     } else if (ISSPACE(ch)) {
 165       f |= F_MIDLINE;
 166       if (n >= MSGBUFSZ) goto full;
 167       b[n++] = ch; nsp++;
 168     } else {
 169       f |= F_MIDLINE;
 170       nsp = 0;
 171       if (n >= MSGBUFTHRESH) goto full;
 172       b[n++] = ch;
 173     }
 174   }
 175 eof:
 176   f |= F_EOF;
 177   goto done;
 178 full:
 179   ungetc(ch, m->fp);
 180 done:
 181   m->f = f;
 182   if (m->f & F_PROGRESS) fprogress_update(&m->ff, n);
 183   return (n);
 184 }
 185
 186 static void textwrite(msgcanon *m, const void *bp, size_t n)
 187 {
 188   const char *p = bp, *l = p + n;
 189   unsigned f = m->f;
 190
 191   while (p < l) {
 192     if (!(f & (F_MIDLINE | F_DETACH)) &&
 193         (*p == '.' || *p == '-'))
 194       putc('.', m->fp);
 195     if (*p == '\n') f &= ~F_MIDLINE;
 196     else f |= F_MIDLINE;
 197     putc(*p, m->fp);
 198     p++;
 199   }
 200   m->f = f;
 201 }
 202
 203 static size_t binreadembed(msgcanon *m, void *bp)
 204 {
 205   size_t n = chunk_read(m->e, bp);
 206   if (m->f & F_PROGRESS) fprogress_update(&m->ff, n);
 207   return (n);
 208 }
 209
 210 static size_t binreaddetach(msgcanon *m, void *bp)
 211 {
 212   size_t n = fread(bp, 1, MSGBUFSZ - 1, m->fp);
 213   if (m->f & F_PROGRESS) fprogress_update(&m->ff, n);
 214   return (n);
 215 }
 216
 217 static void binwriteembed(msgcanon *m, const void *bp, size_t n)
 218   { chunk_write(m->e, bp, n); }
 219
 220 static void nullwrite(msgcanon *m, const void *bp, size_t n) { ; }
 221
 222 static void mcsetup_readfile(msgcanon *m, unsigned f, const char *fn)
 223 {
 224   m->f = F_DETACH | (f & (F_BINARY | F_PROGRESS));
 225   if (!fn || STRCMP(fn, ==, "-")) {
 226     m->fp = stdin;
 227     m->f |= F_NOCLOSE;
 228   } else if ((m->fp = fopen(fn, (f & F_BINARY) ? "rb" : "r")) == 0)
 229     die(EXIT_FAILURE, "couldn't open file `%s': %s", fn, strerror(errno));
 230   if (m->f & F_PROGRESS) {
 231     if (fprogress_init(&m->ff, fn, m->fp)) {
 232       die(EXIT_FAILURE, "failed to initialize progress indicator: %s",
 233           strerror(errno));
 234     }
 235   }
 236   m->read = (f & F_BINARY) ? binreaddetach : textread;
 237 }
 238
 239 static void mcsetup_writenull(msgcanon *m) { m->write = nullwrite; }
 240
 241 static void mcsetup_read(msgcanon *m, unsigned f, enc **ee,
 242                          const char *fn, const char *dfn)
 243 {
 244   enc *e = *ee;
 245
 246   m->f = f | F_NOCLOSE;
 247
 248   if (dfn && !(f & F_DETACH)) die(EXIT_FAILURE, "signature is not detached");
 249   if (f & F_BINARY) {
 250     if (!(f & F_DETACH)) {
 251       m->e = e;
 252       *ee = 0;
 253       m->fp = e->fp;
 254       m->read = binreadembed;
 255       if (m->f & F_PROGRESS) {
 256         if (fprogress_init(&m->ff, fn, m->fp)) {
 257           die(EXIT_FAILURE, "failed to initialize progress indicator: %s",
 258               strerror(errno));
 259         }
 260       }
 261     } else {
 262       m->read = binreaddetach;
 263       if (!dfn || STRCMP(dfn, ==, "-"))
 264         m->fp = stdin;
 265       else if ((m->fp = fopen(dfn, "rb")) == 0)
 266         die(EXIT_FAILURE, "can't open `%s': %s", dfn, strerror(errno));
 267       else
 268         m->f &= ~F_NOCLOSE;
 269       if (m->f & F_PROGRESS) {
 270         if (fprogress_init(&m->ff, dfn, m->fp)) {
 271           die(EXIT_FAILURE, "failed to initialize progress indicator: %s",
 272               strerror(errno));
 273         }
 274       }
 275     }
 276   } else {
 277     m->read = textread;
 278     if (!(f & F_DETACH)) {
 279       if (e->ops->decdone(e) || ferror(e->fp))
 280         die(EXIT_FAILURE, "error at end of signature header");
 281       m->fp = e->fp;
 282       e->ops->destroy(e);
 283       *ee = 0;
 284       if (m->f & F_PROGRESS) {
 285         if (fprogress_init(&m->ff, fn, m->fp)) {
 286           die(EXIT_FAILURE, "failed to initialize progress indicator: %s",
 287               strerror(errno));
 288         }
 289       }
 290     } else {
 291       if (!dfn || STRCMP(dfn, ==, "-"))
 292         m->fp = stdin;
 293       else if ((m->fp = fopen(dfn, "r")) == 0)
 294         die(EXIT_FAILURE, "can't read file `%s': %s", dfn, strerror(errno));
 295       else
 296         m->f &= ~F_NOCLOSE;
 297       if (m->f & F_PROGRESS) {
 298         if (fprogress_init(&m->ff, dfn, m->fp)) {
 299           die(EXIT_FAILURE, "failed to initialize progress indicator: %s",
 300               strerror(errno));
 301         }
 302       }
 303     }
 304   }
 305 }
 306
 307 static void mcsetup_write(msgcanon *m, unsigned f, enc **ee)
 308 {
 309   enc *e = *ee;
 310
 311   m->f = f | F_NOCLOSE;
 312
 313   if (f & F_DETACH)
 314     m->write = nullwrite;
 315   else if (f & F_BINARY) {
 316     m->e = e;
 317     *ee = 0;
 318     m->fp = e->fp;
 319     m->write = binwriteembed;
 320   } else {
 321     if (e->ops->encdone(e) || ferror(e->fp))
 322       die(EXIT_FAILURE, "error at end of signature header");
 323     m->fp = e->fp;
 324     e->ops->destroy(e);
 325     *ee = 0;
 326     m->write = textwrite;
 327   }
 328 }
 329
 330 static void mc_endread(msgcanon *m, const encops *eops, enc **ee)
 331 {
 332   if (!(m->f & F_DETACH)) {
 333     if (m->f & F_BINARY)
 334       *ee = m->e;
 335     else
 336       *ee = initdec(eops, m->fp, checkbdry, "CATSIGN SIGNATURE");
 337   }
 338   if (m->fp && !(m->f & F_NOCLOSE)) {
 339     if (ferror(m->fp) || fclose(m->fp))
 340       die(EXIT_FAILURE, "error closing message file: %s", strerror(errno));
 341   }
 342   if (m->f & F_PROGRESS) fprogress_done(&m->ff);
 343 }
 344
 345 static void mc_endwrite(msgcanon *m, const encops *eops, enc **ee)
 346 {
 347   if (!(m->f & F_BINARY)) {
 348     if (m->f & F_MIDLINE) putc('\n', m->fp);
 349     if (!(m->f & F_DETACH)) {
 350       putc('.', m->fp); putc('\n', m->fp);
 351       *ee = initenc(eops, m->fp, "CATSIGN SIGNATURE");
 352     }
 353   } else if (!(m->f & F_DETACH)) {
 354     chunk_write(m->e, 0, 0);
 355     *ee = m->e;
 356   }
 357   if (m->fp && !(m->f & F_NOCLOSE)) {
 358     if (fflush(m->fp) || ferror(m->fp) || fclose(m->fp))
 359       die(EXIT_FAILURE, "error closing message file: %s", strerror(errno));
 360   }
 361 }
 362
 363 /*----- Signature reading and writing -------------------------------------*/
 364
 365 static void sig_init(sigmsg *s, unsigned f, uint32 keyid)
 366 {
 367   s->f = f & F_SIGMASK;
 368   s->keyid = keyid;
 369   time(&s->t);
 370   s->s = 0;
 371   dstr_create(&s->kh);
 372   dstr_create(&s->sig);
 373 }
 374
 375 static void sig_destroy(sigmsg *s)
 376 {
 377   dstr_destroy(&s->kh);
 378   dstr_destroy(&s->sig);
 379   if (s->s) freesig(s->s);
 380 }
 381
 382 static void sigtobuffer(sigmsg *s, buf *b, int hashp)
 383 {
 384   kludge64 t;
 385
 386   ASSIGN64(t, s->t);
 387   if (hashp) buf_putu16(b, s->f & F_HASHMASK);
 388   else buf_putu16(b, s->f & F_SIGMASK);
 389   buf_putu32(b, s->keyid);
 390   buf_putu32(b, HI64(t));
 391   buf_putu32(b, LO64(t));
 392   buf_putdstr16(b, &s->kh);
 393   assert(BOK(b));
 394 }
 395
 396 static void dohash(ghash *h, const void *p, size_t n)
 397 {
 398   GH_HASH(h, p, n);
 399 }
 400
 401 static void sig_hash(sigmsg *s)
 402 {
 403   octet bb[16384];
 404   buf b;
 405
 406   buf_init(&b, bb, sizeof(bb));
 407   sigtobuffer(s, &b, 1);
 408   dohash(s->s->h, BBASE(&b), BLEN(&b));
 409 }
 410
 411 static void keyhash(key *k, sig *s, dstr *d)
 412 {
 413   ghash *h;
 414   key_filter kf;
 415
 416   h = GH_INIT(s->ch);
 417   kf.f = KCAT_PUB;
 418   kf.m = KF_CATMASK;
 419   key_fingerprint(k, h, &kf);
 420   dstr_ensure(d, GH_CLASS(h)->hashsz);
 421   GH_DONE(h, d->buf + d->len);
 422   d->len += GH_CLASS(h)->hashsz;
 423   GH_DESTROY(h);
 424 }
 425
 426 static void sig_writeheader(enc *e, sigmsg *s)
 427 {
 428   octet bb[16384];
 429   buf b;
 430
 431   buf_init(&b, bb, sizeof(bb));
 432   sigtobuffer(s, &b, 0);
 433   chunk_write(e, BBASE(&b), BLEN(&b));
 434 }
 435
 436 static void sig_writesig(enc *e, sigmsg *s)
 437   { chunk_write(e, s->sig.buf, s->sig.len); }
 438
 439 static void NORETURN diechoke(const char *m, void *p)
 440   { die(EXIT_FAILURE, "%s%s%s", (const char *)p, p ? ": " : "", m); }
 441
 442 static void sig_readheader(enc *e, sigmsg *s,
 443                            void NORETURN (*choke)(const char *, void *),
 444                            void *p)
 445 {
 446   uint16 f;
 447   octet bb[MSGBUFSZ];
 448   uint32 x, y;
 449   kludge64 t;
 450   buf b;
 451   size_t n;
 452
 453   n = chunk_read(e, bb);
 454   buf_init(&b, bb, n);
 455   if (buf_getu16(&b, &f)) choke("missing flags", p);
 456   if (buf_getu32(&b, &x)) choke("missing keyid", p);
 457   sig_init(s, f, x);
 458   if (buf_getu32(&b, &x) || buf_getu32(&b, &y))
 459     choke("missing datestamp", p);
 460   SET64(t, x, y); s->t = GET64(time_t, t);
 461   if (buf_getdstr16(&b, &s->kh))
 462     choke("missing key hash", p);
 463   if (BLEFT(&b))
 464     choke("junk at end", p);
 465 }
 466
 467 static void sig_readsig(enc *e, sigmsg *s)
 468 {
 469   octet bb[MSGBUFSZ];
 470   size_t n;
 471
 472   n = chunk_read(e, bb);
 473   dstr_putm(&s->sig, bb, n);
 474 }
 475
 476 /*----- Signing -----------------------------------------------------------*/
 477
 478 static int sign(int argc, char *argv[])
 479 {
 480   const char *ef = "binary", *fn = 0, *of = 0, *kn = "ccsig", *err;
 481   unsigned f = 0;
 482   key_file kf;
 483   key *k;
 484   sigmsg s;
 485   FILE *ofp = 0;
 486   int i;
 487   char bb[MSGBUFSZ];
 488   size_t n;
 489   dstr d = DSTR_INIT;
 490   const encops *eo;
 491   msgcanon mc_in = MC_INIT, mc_out = MC_INIT;
 492   enc *e;
 493
 494   for (;;) {
 495     static const struct option opt[] = {
 496       { "armour",       0,              0,      'a' },
 497       { "armor",        0,              0,      'a' },
 498       { "binary",       0,              0,      'b' },
 499       { "detach",       0,              0,      'd' },
 500       { "key",          OPTF_ARGREQ,    0,      'k' },
 501       { "format",       OPTF_ARGREQ,    0,      'f' },
 502       { "output",       OPTF_ARGREQ,    0,      'o' },
 503       { "progress",     0,              0,      'p' },
 504       { "text",         0,              0,      't' },
 505       { "nocheck",      0,              0,      'C' },
 506       { 0,              0,              0,      0 }
 507     };
 508     i = mdwopt(argc, argv, "k:f:o:abdptC", opt, 0, 0, 0);
 509     if (i < 0) break;
 510     switch (i) {
 511       case 'k': kn = optarg; break;
 512       case 'f': ef = optarg; break;
 513       case 'o': of = optarg; break;
 514       case 'a': ef = "pem"; break;
 515       case 't': f &= ~F_BINARY; break;
 516       case 'b': f |= F_BINARY; break;
 517       case 'd': f |= F_DETACH; break;
 518       case 'C': f |= F_NOCHECK; break;
 519       case 'p': f |= F_PROGRESS; break;
 520       default: f |= F_BOGUS; break;
 521     }
 522   }
 523   if (argc - optind > 1 || (f & F_BOGUS))
 524     die(EXIT_FAILURE, "Usage: sign [-OPTIONS] [FILE]");
 525
 526   if (key_open(&kf, keyring, KOPEN_READ, key_moan, 0))
 527     die(EXIT_FAILURE, "can't open keyring `%s'", keyring);
 528   if ((k = key_bytag(&kf, kn)) == 0)
 529     die(EXIT_FAILURE, "key `%s' not found", kn);
 530
 531   if ((eo = getenc(ef)) == 0)
 532     die(EXIT_FAILURE, "encoding `%s' not found", ef);
 533
 534   fn = (optind >= argc) ? 0 : argv[optind++];
 535
 536   if (!of || STRCMP(of, ==, "-"))
 537     ofp = stdout;
 538   else if ((ofp = fopen(of, eo->wmode)) == 0) {
 539     die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 540         of, strerror(errno));
 541   }
 542
 543   /* --- Start the work --- */
 544
 545   sig_init(&s, f, k->id);
 546   dstr_reset(&d);
 547   key_fulltag(k, &d);
 548   s.s = getsig(k, "ccsig", 1);
 549   if (!(f & F_NOCHECK) && (err = s.s->ops->check(s.s)) != 0)
 550     moan("key %s fails check: %s", d.buf, err);
 551   keyhash(k, s.s, &s.kh);
 552   e = initenc(eo, ofp,
 553               (f & F_DETACH) ? "CATSIGN SIGNATURE" :
 554               (f & F_BINARY) ? "CATSIGN MESSAGE" :
 555               "CATSIGN MESSAGE HEADER");
 556   sig_writeheader(e, &s);
 557
 558   /* --- Hash the message --- */
 559
 560   mcsetup_readfile(&mc_in, f, fn);
 561   mcsetup_write(&mc_out, f, &e);
 562   sig_hash(&s);
 563   for (;;) {
 564     n = mc_in.read(&mc_in, bb);
 565     if (!n) break;
 566     dohash(s.s->h, bb, n);
 567     mc_out.write(&mc_out, bb, n);
 568   }
 569   mc_endread(&mc_in, 0, 0);
 570   mc_endwrite(&mc_out, eo, &e);
 571
 572   /* --- Write the signature --- */
 573
 574   if (s.s->ops->doit(s.s, &s.sig))
 575     die(EXIT_FAILURE, "signature failed");
 576   sig_writesig(e, &s);
 577   e->ops->encdone(e);
 578   if (fflush(ofp) || ferror(ofp) || fclose(ofp))
 579     die(EXIT_FAILURE, "error writing signature: %s", strerror(errno));
 580
 581   /* --- All done --- */
 582
 583   freeenc(e);
 584   key_close(&kf);
 585   sig_destroy(&s);
 586   dstr_destroy(&d);
 587   return (0);
 588 }
 589
 590 /*----- Verifying ---------------------------------------------------------*/
 591
 592 typedef struct vrfctx {
 593   unsigned f, m;
 594   int verb;
 595   const char *what;
 596 } vrfctx;
 597
 598 static int vrfbdry(const char *b, void *p)
 599 {
 600   vrfctx *v = p;
 601
 602   if (STRCMP(b, ==, "CATSIGN MESSAGE")) {
 603     v->f |= F_BINARY;
 604     v->m |= F_BINARY | F_DETACH;
 605     return (1);
 606   } else if (STRCMP(b, ==, "CATSIGN MESSAGE HEADER")) {
 607     v->m |= F_BINARY | F_DETACH;
 608     return (1);
 609   } else if (STRCMP(b, ==, "CATSIGN SIGNATURE")) {
 610     v->f |= F_DETACH;
 611     v->m |= F_DETACH;
 612     return (1);
 613   } else
 614     return (0);
 615 }
 616
 617 static void NORETURN vrfchoke(const char *m, void *p)
 618 {
 619   vrfctx *v = p;
 620   if (v->verb) printf("FAIL %s: %s\n", v->what, m);
 621   exit(EXIT_FAILURE);
 622 }
 623
 624 static int verify(int argc, char *argv[])
 625 {
 626   const char *ef = "binary", *of = 0, *fn, *dfn = 0, *kn = 0, *err;
 627   vrfctx v = { 0, 0, 1 };
 628   key_file kf;
 629   key *k, *kk = 0;
 630   sigmsg s;
 631   FILE *fp, *ofp = 0, *rfp = 0;
 632   fprogress ff;
 633   struct tm *tm;
 634   int i;
 635   char bb[MSGBUFSZ];
 636   size_t n;
 637   time_t t_fresh = 0;
 638   dstr d = DSTR_INIT, dd = DSTR_INIT;
 639   const encops *eo;
 640   msgcanon mc_in = MC_INIT;
 641   enc *e;
 642
 643   for (;;) {
 644     static const struct option opt[] = {
 645       { "armour",       0,              0,      'a' },
 646       { "armor",        0,              0,      'a' },
 647       { "buffer",       0,              0,      'b' },
 648       { "key",          OPTF_ARGREQ,    0,      'k' },
 649       { "format",       OPTF_ARGREQ,    0,      'f' },
 650       { "output",       OPTF_ARGREQ,    0,      'o' },
 651       { "progress",     0,              0,      'p' },
 652       { "quiet",        0,              0,      'q' },
 653       { "utc",          0,              0,      'u' },
 654       { "fresh-time",   0,              0,      't' },
 655       { "gmt",          0,              0,      'u' },
 656       { "verbose",      0,              0,      'v' },
 657       { "nocheck",      0,              0,      'C' },
 658       { 0,              0,              0,      0 }
 659     };
 660     i = mdwopt(argc, argv, "k:f:o:abpqt:uvC", opt, 0, 0, 0);
 661     if (i < 0) break;
 662     switch (i) {
 663       case 'a': ef = "pem"; break;
 664       case 'b': v.f |= F_BUFFER; break;
 665       case 'k': kn = optarg; break;
 666       case 'f': ef = optarg; break;
 667       case 'o': of = optarg; break;
 668       case 'u': v.f |= F_UTC; break;
 669       case 'C': v.f |= F_NOCHECK; break;
 670       case 't':
 671         if (STRCMP(optarg, ==, "always")) t_fresh = 0;
 672         else if ((t_fresh = get_date(optarg, 0)) < 0)
 673           die(EXIT_FAILURE, "bad freshness time");
 674         break;
 675       case 'q': if (v.verb > 0) v.verb--; break;
 676       case 'v': if (v.verb < 10) v.verb++; break;
 677       case 'p': v.f |= F_PROGRESS; break;
 678       default: v.f |= F_BOGUS; break;
 679     }
 680   }
 681   if (argc - optind > 2 || (v.f & F_BOGUS))
 682     die(EXIT_FAILURE, "Usage: verify [-OPTIONS] [FILE [MESSAGE]]");
 683
 684   if ((eo = getenc(ef)) == 0)
 685     die(EXIT_FAILURE, "encoding `%s' not found", ef);
 686
 687   fn = optind < argc ? argv[optind++] : "-";
 688   if (STRCMP(fn, ==, "-"))
 689     fp = stdin;
 690   else if ((fp = fopen(fn, eo->rmode)) == 0) {
 691     die(EXIT_FAILURE, "couldn't open file `%s': %s",
 692         fn, strerror(errno));
 693   }
 694
 695   if (key_open(&kf, keyring, KOPEN_READ, key_moan, 0))
 696     die(EXIT_FAILURE, "can't open keyring `%s'", keyring);
 697   if (kn && (kk = key_bytag(&kf, kn)) == 0)
 698     die(EXIT_FAILURE, "key `%s' not found", kn);
 699
 700   e = initdec(eo, fp, vrfbdry, &v);
 701
 702   /* --- Read the header chunk --- */
 703
 704   v.what = "malformed header";
 705   sig_readheader(e, &s, vrfchoke, &v);
 706
 707   if (((s.f ^ v.f) & v.m) != 0) {
 708     if (v.verb) printf("FAIL boundary string inconsistent with contents\n");
 709     exit(EXIT_FAILURE);
 710   }
 711   v.f |= s.f;
 712
 713   if ((k = key_byid(&kf, s.keyid)) == 0) {
 714     if (v.verb) printf("FAIL key id %08lx not found\n",
 715                        (unsigned long)s.keyid);
 716     exit(EXIT_FAILURE);
 717   }
 718   if (kk && k != kk) {
 719     if (v.verb) {
 720       dstr_reset(&d); key_fulltag(k, &d);
 721       dstr_reset(&dd); key_fulltag(kk, &dd);
 722       printf("FAIL signing key is %s; expected key %s\n", d.buf, dd.buf);
 723     }
 724     exit(EXIT_FAILURE);
 725   }
 726
 727   s.s = getsig(k, "ccsig", 0);
 728   dstr_reset(&d); key_fulltag(k, &d);
 729   if (!(v.f & F_NOCHECK) && v.verb && (err = s.s->ops->check(s.s)) != 0)
 730     printf("WARN verification key %s fails check: %s\n", d.buf, err);
 731
 732   dstr_reset(&dd); keyhash(k, s.s, &dd);
 733   if (dd.len != s.kh.len || MEMCMP(dd.buf, !=, s.kh.buf, dd.len)) {
 734     if (v.verb) printf("FAIL key hash mismatch\n");
 735     exit(EXIT_FAILURE);
 736   }
 737
 738   /* --- Now a merry dance --- */
 739
 740   if (v.f & F_DETACH)
 741     sig_readsig(e, &s);
 742   if (optind < argc)
 743     dfn = argv[optind++];
 744   mcsetup_read(&mc_in, v.f, &e, fn, dfn);
 745
 746   if (!of && (v.f & F_DETACH)) {
 747     rfp = ofp = 0;
 748     v.f &= ~F_BUFFER;
 749   } else if (!of || STRCMP(of, ==, "-")) {
 750     v.f |= F_BUFFER;
 751     ofp = stdout;
 752   } else if (of && !(v.f & F_BUFFER)) {
 753     if ((ofp = fopen(of, (v.f & F_BINARY) ? "wb" : "w")) == 0) {
 754       die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 755           of, strerror(errno));
 756     }
 757     rfp = ofp;
 758   }
 759   if ((v.f & F_BUFFER) && (rfp = tmpfile()) == 0)
 760     die(EXIT_FAILURE, "couldn't create temporary file: %s", strerror(errno));
 761
 762   /* --- Read the message and verify the signature --- */
 763
 764   sig_hash(&s);
 765   for (;;) {
 766     n = mc_in.read(&mc_in, bb);
 767     if (!n) break;
 768     dohash(s.s->h, bb, n);
 769     if (rfp) fwrite(bb, 1, n, rfp);
 770   }
 771   mc_endread(&mc_in, eo, &e);
 772   if (!(v.f & F_DETACH))
 773     sig_readsig(e, &s);
 774   if (rfp && (ferror(rfp) || fflush(rfp))) {
 775     if (v.verb) printf("FAIL error writing message: %s\n", strerror(errno));
 776     exit(EXIT_FAILURE);
 777   }
 778
 779   /* --- Check the signature --- */
 780
 781   if (s.s->ops->doit(s.s, &s.sig)) {
 782     if (v.verb) printf("FAIL signature verification failed\n");
 783     exit(EXIT_FAILURE);
 784   }
 785   if (t_fresh && s.t < t_fresh) {
 786     if (v.verb) printf("FAIL signature is stale\n");
 787     exit(EXIT_FAILURE);
 788   }
 789   if (s.t > time(0)) {
 790     if (v.verb) printf("FAIL signature timestamp in the future\n");
 791     exit(EXIT_FAILURE);
 792   }
 793   if (v.verb) {
 794     tm = (v.f & F_UTC) ? gmtime(&s.t) : localtime(&s.t);
 795     strftime(bb, sizeof(bb), "%Y-%m-%d %H:%M:%S %Z", tm);
 796     printf("INFO good-signature %s\n", d.buf);
 797     printf("INFO date %s\n", bb);
 798   }
 799
 800   /* --- Unbuffer buffered input --- */
 801
 802   if (v.f & F_BUFFER) {
 803     if (!ofp && (ofp = fopen(of, "wb")) == 0) {
 804       die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 805           of, strerror(errno));
 806     }
 807     rewind(rfp);
 808     if (v.f & F_PROGRESS) fprogress_init(&ff, "copying buffer", rfp);
 809     if (v.verb && ofp == stdout) printf("DATA\n");
 810     for (;;) {
 811       n = fread(bb, 1, sizeof(bb), rfp);
 812       if (!n) break;
 813       if (v.f & F_PROGRESS) fprogress_update(&ff, n);
 814       if (fwrite(bb, 1, n, ofp) < n) {
 815         if (v.f & F_PROGRESS) fprogress_done(&ff);
 816         die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
 817       }
 818     }
 819     if (v.f & F_PROGRESS) fprogress_done(&ff);
 820     if (ferror(rfp) || fclose(rfp))
 821       die(EXIT_FAILURE, "error unbuffering output: %s", strerror(errno));
 822   }
 823   if (ofp && (fflush(ofp) || ferror(ofp) || fclose(ofp)))
 824       die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
 825
 826   /* --- Tidy up --- */
 827
 828   e->ops->decdone(e);
 829   if (v.verb && ofp != stdout)
 830     printf("OK verified successfully\n");
 831   freeenc(e);
 832   key_close(&kf);
 833   sig_destroy(&s);
 834   dstr_destroy(&d);
 835   dstr_destroy(&dd);
 836   return (0);
 837 }
 838
 839 /*----- Reformatting ------------------------------------------------------*/
 840
 841 static int format(int argc, char *argv[])
 842 {
 843   const char *ief = "binary", *oef = "binary";
 844   const char *fn, *dfn = 0, *of = 0, *mf = 0;
 845   sigmsg s;
 846   FILE *fp, *ofp = 0, *mfp = 0;
 847   int i;
 848   size_t n;
 849   msgcanon mc_in = MC_INIT, mc_out = MC_INIT;
 850   char bb[MSGBUFSZ];
 851   vrfctx v = { 0, 0, 1 };
 852   unsigned f = 0, fm = ~F_SIGMASK, sf;
 853   const encops *ieo, *oeo;
 854   enc *ie, *oe;
 855
 856   for (;;) {
 857     static const struct option opt[] = {
 858       { "armour-in",    0,              0,      'a' },
 859       { "armor-in",     0,              0,      'a' },
 860       { "armour-out",   0,              0,      'A' },
 861       { "armor-out",    0,              0,      'A' },
 862       { "detach",       0,              0,      'D' },
 863       { "embed",        0,              0,      'E' },
 864       { "format-in",    OPTF_ARGREQ,    0,      'f' },
 865       { "format-out",   OPTF_ARGREQ,    0,      'F' },
 866       { "message",      OPTF_ARGREQ,    0,      'm' },
 867       { "output",       OPTF_ARGREQ,    0,      'o' },
 868       { "progress",     0,              0,      'p' },
 869       { 0,              0,              0,      0 }
 870     };
 871     i = mdwopt(argc, argv, "f:F:m:o:apADE", opt, 0, 0, 0);
 872     if (i < 0) break;
 873     switch (i) {
 874       case 'a': ief = "pem"; break;
 875       case 'A': oef = "pem"; break;
 876       case 'f': ief = optarg; break;
 877       case 'F': oef = optarg; break;
 878       case 'D': f |= F_DETACH; fm |= F_DETACH; break;
 879       case 'E': f &= ~F_DETACH; fm |= F_DETACH; break;
 880       case 'm': mf = optarg; break;
 881       case 'o': of = optarg; break;
 882       case 'p': f |= F_PROGRESS; break;
 883       default: f |= F_BOGUS; break;
 884     }
 885   }
 886
 887   if (argc - optind > 2 || (f & F_BOGUS))
 888     die(EXIT_FAILURE, "Usage: format [-OPTIONS] [FILE [MESSAGE]]");
 889
 890   if ((ieo = getenc(ief)) == 0)
 891     die(EXIT_FAILURE, "encoding `%s' not found", ief);
 892   if ((oeo = getenc(oef)) == 0)
 893     die(EXIT_FAILURE, "encoding `%s' not found", oef);
 894
 895   fn = optind < argc ? argv[optind++] : "-";
 896   if (STRCMP(fn, ==, "-"))
 897     fp = stdin;
 898   else if ((fp = fopen(fn, ieo->rmode)) == 0) {
 899     die(EXIT_FAILURE, "couldn't open file `%s': %s",
 900         fn, strerror(errno));
 901   }
 902
 903   if (optind < argc)
 904     dfn = argv[optind++];
 905
 906   ie = initdec(ieo, fp, vrfbdry, &v);
 907
 908   /* --- Read the header chunk --- */
 909
 910   sig_readheader(ie, &s, diechoke, "malformed header");
 911
 912   if (((s.f ^ v.f) & v.m) != 0)
 913     moan("boundary string inconsistent with contents (ignoring)");
 914
 915   mcsetup_read(&mc_in, s.f, &ie, fn, dfn);
 916
 917   /* --- Prepare the output stuff --- */
 918
 919   if (!of && !mf) of = "-";
 920   sf = s.f;
 921   f = (f & fm) | (s.f & ~fm);
 922   s.f = f & F_SIGMASK;
 923
 924   if (sf & F_DETACH)
 925     sig_readsig(ie, &s);
 926
 927   if (!of)
 928     mcsetup_writenull(&mc_out);
 929   else {
 930     if (STRCMP(of, ==, "-"))
 931       ofp = stdout;
 932     else if ((ofp = fopen(of, oeo->wmode)) == 0) {
 933       die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 934           of, strerror(errno));
 935     }
 936     oe = initenc(oeo, ofp,
 937                  (f & F_DETACH) ? "CATSIGN SIGNATURE" :
 938                  (f & F_BINARY) ? "CATSIGN MESSAGE" :
 939                  "CATSIGN MESSAGE HEADER");
 940     sig_writeheader(oe, &s);
 941     mcsetup_write(&mc_out, f, &oe);
 942   }
 943
 944   if (mf) {
 945     if (STRCMP(mf, ==, "-"))
 946       mfp = stdout;
 947     else if ((mfp = fopen(mf, (f & F_BINARY) ? "wb" : "w")) == 0) {
 948       die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
 949           mf, strerror(errno));
 950     }
 951   }
 952
 953   /* --- Wade through the message body --- */
 954
 955   for (;;) {
 956     n = mc_in.read(&mc_in, bb);
 957     if (!n) break;
 958     mc_out.write(&mc_out, bb, n);
 959     if (mfp) fwrite(bb, 1, n, mfp);
 960   }
 961   mc_endread(&mc_in, ieo, &ie);
 962   if (of) mc_endwrite(&mc_out, oeo, &oe);
 963
 964   /* --- Write the signature --- */
 965
 966   if (!(sf & F_DETACH))
 967     sig_readsig(ie, &s);
 968   if (of) {
 969     sig_writesig(oe, &s);
 970     oe->ops->encdone(oe);
 971   }
 972
 973   /* --- All done --- */
 974
 975   ie->ops->decdone(ie);
 976   if (ferror(fp) || fclose(fp))
 977     die(EXIT_FAILURE, "error reading input signature: %s", strerror(errno));
 978   if (ofp && (fflush(ofp) || ferror(ofp) || fclose(ofp)))
 979     die(EXIT_FAILURE, "error writing output signature: %s", strerror(errno));
 980   if (mfp && (fflush(mfp) || ferror(mfp) || fclose(mfp)))
 981     die(EXIT_FAILURE, "error writing output message: %s", strerror(errno));
 982   freeenc(ie);
 983   if (of) freeenc(oe);
 984   sig_destroy(&s);
 985   return (0);
 986 }
 987
 988 static void NORETURN infochoke(const char *m, void *p)
 989 {
 990   vrfctx *v = p;
 991   printf("BAD %s: %s\n", v->what, m);
 992   exit(EXIT_FAILURE);
 993 }
 994
 995 static void infokeyreport(const char *file, int line,
 996                           const char *err, void *p)
 997 { /*whatever*/; }
 998
 999 static int info(int argc, char *argv[])
1000 {
1001   const char *ef = "binary";
1002   vrfctx v = { 0, 0, 1 };
1003   key_file kf;
1004   key *k;
1005   sigmsg s;
1006   FILE *fp;
1007   int i;
1008   struct tm *tm;
1009   char bb[256];
1010   dstr d = DSTR_INIT;
1011   const encops *eo;
1012   enc *e;
1013
1014   for (;;) {
1015     static const struct option opt[] = {
1016       { "armour",       0,              0,      'a' },
1017       { "armor",        0,              0,      'a' },
1018       { "format",       OPTF_ARGREQ,    0,      'f' },
1019       { "gmt",          0,              0,      'u' },
1020       { "utc",          0,              0,      'u' },
1021       { 0,              0,              0,      0 }
1022     };
1023     i = mdwopt(argc, argv, "f:au", opt, 0, 0, 0);
1024     if (i < 0) break;
1025     switch (i) {
1026       case 'a': ef = "pem"; break;
1027       case 'f': ef = optarg; break;
1028       case 'u': v.f |= F_UTC; break;
1029       default: v.f |= F_BOGUS; break;
1030     }
1031   }
1032   if (argc - optind > 1 || (v.f & F_BOGUS))
1033     die(EXIT_FAILURE, "Usage: info [-OPTIONS] [FILE]");
1034
1035   if ((eo = getenc(ef)) == 0)
1036     die(EXIT_FAILURE, "encoding `%s' not found", ef);
1037
1038   if (optind >= argc)
1039     fp = stdin;
1040   else if (STRCMP(argv[optind], ==, "-")) {
1041     fp = stdin;
1042     optind++;
1043   } else if ((fp = fopen(argv[optind], eo->rmode)) == 0) {
1044     die(EXIT_FAILURE, "couldn't open file `%s': %s",
1045         argv[optind], strerror(errno));
1046   } else
1047     optind++;
1048
1049   if (key_open(&kf, keyring, KOPEN_READ, infokeyreport, 0)) {
1050     printf("NOTE can't open keyring `%s'\n", keyring);
1051     keyring = 0;
1052   }
1053   e = initdec(eo, fp, vrfbdry, &v);
1054
1055   v.what = "malformed header";
1056   sig_readheader(e, &s, infochoke, &v);
1057
1058   printf("INFO flags %sdetach %sbinary\n",
1059          (s.f & F_DETACH) ? "" : "!",
1060          (s.f & F_BINARY) ? "" : "!");
1061
1062   if (((s.f ^ v.f) & v.m) != 0) {
1063     printf("WARN boundary string inconsistent with contents\n");
1064     printf("INFO expected-flags");
1065     if (v.m & F_DETACH) printf(" %sdetach", (v.f & F_DETACH) ? "" : "!");
1066     if (v.m & F_BINARY) printf(" %sbinary", (v.f & F_BINARY) ? "" : "!");
1067     putchar('\n');
1068   }
1069   v.f |= s.f;
1070
1071   tm = (v.f & F_UTC) ? gmtime(&s.t) : localtime(&s.t);
1072   strftime(bb, sizeof(bb), "%Y-%m-%d %H:%M:%S %Z", tm);
1073   printf("INFO date %s\n", bb);
1074
1075   if (keyring && (k = key_byid(&kf, s.keyid)) != 0) {
1076     dstr_reset(&d); key_fulltag(k, &d);
1077     printf("INFO key %s\n", d.buf);
1078   } else
1079     printf("INFO unknown-key %08lx\n", (unsigned long)s.keyid);
1080
1081   if (keyring) key_close(&kf);
1082   dstr_destroy(&d);
1083   sig_destroy(&s);
1084   return (0);
1085 }
1086
1087 /*----- Main code ---------------------------------------------------------*/
1088
1089 #define LISTS(LI)                                                       \
1090   LI("Lists", list,                                                     \
1091      listtab[i].name, listtab[i].name)                                  \
1092   LI("Signature schemes", sig,                                          \
1093      sigtab[i].name, sigtab[i].name)                                    \
1094   LI("Encodings", enc,                                                  \
1095      enctab[i].name, enctab[i].name)                                    \
1096   LI("Hash functions", hash,                                            \
1097      ghashtab[i], ghashtab[i]->name)
1098
1099 MAKELISTTAB(listtab, LISTS)
1100
1101 int cmd_show(int argc, char *argv[])
1102 {
1103   return (displaylists(listtab, argv + 1));
1104 }
1105
1106 static int cmd_help(int, char **);
1107
1108 static cmd cmdtab[] = {
1109   { "help", cmd_help, "help [COMMAND...]" },
1110   { "show", cmd_show, "show [ITEM...]" },
1111   CMD_ENCODE,
1112   CMD_DECODE,
1113   { "sign", sign,
1114     "sign [-adptC] [-k TAG] [-f FORMAT] [-o OUTPUT] [FILE]", "\
1115 Options:\n\
1116 \n\
1117 -a, --armour            Same as `-f pem'.\n\
1118 -b, --binary            Treat the input message as binary data.\n\
1119 -d, --detach            Produce a detached signature.\n\
1120 -f, --format=FORMAT     Encode as FORMAT.\n\
1121 -k, --key=TAG           Use public encryption key named by TAG.\n\
1122 -o, --output=FILE       Write output to FILE.\n\
1123 -p, --progress          Show progress on large files.\n\
1124 -t, --text              Canonify input message as a text file.\n\
1125 -C, --nocheck           Don't check the private key.\n\
1126 " },
1127   { "verify", verify,
1128     "verify [-abpquvC] [-f FORMAT] [-k TAG] [-o OUTPUT]\n\t\
1129 [FILE [MESSAGE]]", "\
1130 Options:\n\
1131 \n\
1132 -a, --armour            Same as `-f pem'.\n\
1133 -b, --buffer            Buffer message until signature is verified.\n\
1134 -f, --format=FORMAT     Decode as FORMAT.\n\
1135 -k, --key=TAG           Require that the message be signed by key TAG.\n\
1136 -o, --output=FILE       Write message to FILE.\n\
1137 -p, --progress          Show progress on large files.\n\
1138 -q, --quiet             Produce fewer messages.\n\
1139 -t, --freshtime=TIME    Only accept signatures made after this time.\n\
1140 -u, --utc               Show dates in UTC rather than local time.\n\
1141 -v, --verbose           Produce more verbose messages.\n\
1142 -C, --nocheck           Don't check the public key.\n\
1143 " },
1144   { "info", info,
1145     "info [-au] [-f FORMAT] [FILE]", "\
1146 Options:\n\
1147 \n\
1148 -a, --armour            Same as `-f pem'.\n\
1149 -f, --format=FORMAT     Decode as FORMAT.\n\
1150 -u, --utc               Show dates in UTC rather than local time.\n\
1151 "},
1152   { "format", format,
1153     "format [-apuADE] [-f FORMAT] [-F format] [-m FILE] [-o FILE]\n\t\
1154 [FILE [MESSAGE]]", "\
1155 Options:\n\
1156 \n\
1157 -a, --armour-in         Same as `-f pem'.\n\
1158 -A, --armour-out        Same as `-F pem'.\n\
1159 -D, --detach            Create detached signature.\n\
1160 -E, --embed             Create signature with embedded message.\n\
1161 -f, --format-in=FORMAT  Decode input as FORMAT.\n\
1162 -F, --format-out=FORMAT Encode output as FORMAT.\n\
1163 -m, --message=FILE      Write message to FILE.\n\
1164 -o, --output=FILE       Write new signature to FILE.\n\
1165 -p, --progress          Show progress on large files.\n\
1166 "},
1167   { 0, 0, 0 }
1168 }; /* " Emacs seems confused. */
1169
1170 static int cmd_help(int argc, char **argv)
1171 {
1172   sc_help(cmdtab, stdout, argv + 1);
1173   return (0);
1174 }
1175
1176 void version(FILE *fp)
1177 {
1178   pquis(fp, "$, Catacomb version " VERSION "\n");
1179 }
1180
1181 static void usage(FILE *fp)
1182 {
1183   pquis(fp, "Usage: $ [-k KEYRING] COMMAND [ARGS]\n");
1184 }
1185
1186 void help_global(FILE *fp)
1187 {
1188   usage(fp);
1189   fputs("\n\
1190 Sign and verify data.\n\
1191 \n\
1192 Global command-line options:\n\
1193 \n\
1194 -h, --help [COMMAND...] Show this help message, or help for COMMANDs.\n\
1195 -v, --version           Show program version number.\n\
1196 -u, --usage             Show a terse usage message.\n\
1197 \n\
1198 -k, --keyring=FILE      Read keys from FILE.\n",
1199         fp);
1200 }
1201
1202 /* --- @main@ --- *
1203  *
1204  * Arguments:   @int argc@ = number of command line arguments
1205  *              @char *argv[]@ = vector of command line arguments
1206  *
1207  * Returns:     Zero if successful, nonzero otherwise.
1208  *
1209  * Use:         Encrypts or decrypts files.
1210  */
1211
1212 int main(int argc, char *argv[])
1213 {
1214   unsigned f = 0;
1215
1216 #define f_bogus 1u
1217
1218   /* --- Initialize the library --- */
1219
1220   ego(argv[0]);
1221   sub_init();
1222   rand_noisesrc(RAND_GLOBAL, &noise_source);
1223   rand_seed(RAND_GLOBAL, 160);
1224
1225   /* --- Parse options --- */
1226
1227   for (;;) {
1228     static struct option opts[] = {
1229       { "help",         0,              0,      'h' },
1230       { "version",      0,              0,      'v' },
1231       { "usage",        0,              0,      'u' },
1232       { "keyring",      OPTF_ARGREQ,    0,      'k' },
1233       { 0,              0,              0,      0 }
1234     };
1235     int i = mdwopt(argc, argv, "+hvu k:", opts, 0, 0, 0);
1236     if (i < 0)
1237       break;
1238     switch (i) {
1239       case 'h':
1240         sc_help(cmdtab, stdout, argv + optind);
1241         exit(0);
1242         break;
1243       case 'v':
1244         version(stdout);
1245         exit(0);
1246         break;
1247       case 'u':
1248         usage(stdout);
1249         exit(0);
1250       case 'k':
1251         keyring = optarg;
1252         break;
1253       default:
1254         f |= f_bogus;
1255         break;
1256     }
1257   }
1258
1259   argc -= optind;
1260   argv += optind;
1261   optind = 0;
1262   if (f & f_bogus || argc < 1) {
1263     usage(stderr);
1264     exit(EXIT_FAILURE);
1265   }
1266
1267   /* --- Dispatch to the correct subcommand handler --- */
1268
1269   return (findcmd(cmdtab, argv[0])->cmd(argc, argv));
1270
1271 #undef f_bogus
1272 }
1273
1274 /*----- That's all, folks -------------------------------------------------*/