progs/perftest.c: Use from Glibc syscall numbers.

[catacomb] / progs / catsign.c

/* -*-c-*-
 *
 * Sign files
 *
 * (c) 2005 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------*
 *
 * This file is part of Catacomb.
 *
 * Catacomb is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Library General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * Catacomb is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with Catacomb; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 */

/*----- Header files ------------------------------------------------------*/

#define _FILE_OFFSET_BITS 64

#include "config.h"

#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

#include <mLib/base64.h>
#include <mLib/dstr.h>
#include <mLib/macros.h>
#include <mLib/mdwopt.h>
#include <mLib/quis.h>
#include <mLib/report.h>
#include <mLib/sub.h>

#include "buf.h"
#include "rand.h"
#include "noise.h"
#include "mprand.h"
#include "key.h"
#include "getdate.h"
#include "cc.h"

#include "ectab.h"
#include "ptab.h"

/*----- Static variables --------------------------------------------------*/

static const char *keyring = "keyring";

/*----- Data formats ------------------------------------------------------*
 *
 * Our crypto stuff is split into three parts: a header describing the key,
 * the message itself, and the signature.  In a detached signature, the
 * message is separate, and the header and signature are combined into one
 * encoded chunk.  In an attached signature, the message is included.  There
 * are two forms of message: binary and text.  Binary messages are divided
 * into chunks, each preceded by a 2-octet length, and terminated by a
 * zero-length chunk.  Text messages are byte-stuffed, as for RFC821, and
 * trailing whitespace before a newline is ignored.
 */

typedef struct sigmsg {
  unsigned f;				/* Flags */
#define F_DETACH 1u
#define F_BINARY 2u
#define F_SIGMASK 3u
#define F_HASHMASK (F_BINARY)
  uint32 keyid;				/* Key identifier */
  time_t t;				/* When the signature was made */
  dstr kh;				/* Key fingerprint (sanity check) */
  dstr sig;				/* Signature */
  sig *s;				/* Signature algorithm */
} sigmsg;

#define F_MIDLINE 16u
#define F_EOF 32u
#define F_NOCLOSE 64u
#define F_BOGUS 128u
#define F_BUFFER 256u
#define F_UTC 512u
#define F_NOCHECK 1024u
#define F_PROGRESS 2048u

/*----- Chunk I/O ---------------------------------------------------------*/

static void chunk_write(enc *e, const void *p, size_t n)
{
  octet b[2];

  assert(n <= 0xffff);
  STORE16(b, n);
  if (e->ops->write(e, b, 2) || e->ops->write(e, p, n))
    die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
}

static size_t chunk_read(enc *e, void *p)
{
  octet b[2];
  size_t n;

  if (e->ops->read(e, b, 2) != 2)
    goto err;
  n = LOAD16(b);
  if (n && e->ops->read(e, p, n) != n)
    goto err;
  return (n);

err:
  if (!errno) die(EXIT_FAILURE, "unexpected end-of-file on input");
  else die(EXIT_FAILURE, "error reading input: %s", strerror(errno));
  return (0);
}

/*----- Message canonification --------------------------------------------*/

#define MSGBUFSZ 65536
#define MSGBUFTHRESH 32768

typedef struct msgcanon {
  unsigned f;
  FILE *fp;
  enc *e;
  fprogress ff;
  size_t (*read)(struct msgcanon *, void *);
  void (*write)(struct msgcanon *, const void *, size_t);
  void (*close)(struct msgcanon *);
} msgcanon;

#define MC_INIT { 0 }

static size_t textread(msgcanon *m, void *bp)
{
  size_t n = 0, nsp = 0;
  int ch;
  char *b = bp;
  unsigned f = m->f;

  if (f & F_EOF) return (0);
  for (;;) {
    if ((ch = getc(m->fp)) == EOF) goto eof;
    if (!(f & (F_DETACH | F_MIDLINE)) && ch == '.') {
      ch = getc(m->fp);
      if (ch == '\n') goto eof;
    }
    if (ch == '\n') {
      n -= nsp; nsp = 0;
      if (n >= MSGBUFTHRESH) goto full;
      b[n++] = ch;
      f &= ~F_MIDLINE;
    } else if (ISSPACE(ch)) {
      f |= F_MIDLINE;
      if (n >= MSGBUFSZ) goto full;
      b[n++] = ch; nsp++;
    } else {
      f |= F_MIDLINE;
      nsp = 0;
      if (n >= MSGBUFTHRESH) goto full;
      b[n++] = ch;
    }
  }
eof:
  f |= F_EOF;
  goto done;
full:
  ungetc(ch, m->fp);
done:
  m->f = f;
  if (m->f & F_PROGRESS) fprogress_update(&m->ff, n);
  return (n);
}

static void textwrite(msgcanon *m, const void *bp, size_t n)
{
  const char *p = bp, *l = p + n;
  unsigned f = m->f;

  while (p < l) {
    if (!(f & (F_MIDLINE | F_DETACH)) &&
	(*p == '.' || *p == '-'))
      putc('.', m->fp);
    if (*p == '\n') f &= ~F_MIDLINE;
    else f |= F_MIDLINE;
    putc(*p, m->fp);
    p++;
  }
  m->f = f;
}

static size_t binreadembed(msgcanon *m, void *bp)
{
  size_t n = chunk_read(m->e, bp);
  if (m->f & F_PROGRESS) fprogress_update(&m->ff, n);
  return (n);
}

static size_t binreaddetach(msgcanon *m, void *bp)
{
  size_t n = fread(bp, 1, MSGBUFSZ - 1, m->fp);
  if (m->f & F_PROGRESS) fprogress_update(&m->ff, n);
  return (n);
}

static void binwriteembed(msgcanon *m, const void *bp, size_t n)
  { chunk_write(m->e, bp, n); }

static void nullwrite(msgcanon *m, const void *bp, size_t n) { ; }

static void mcsetup_readfile(msgcanon *m, unsigned f, const char *fn)
{
  m->f = F_DETACH | (f & (F_BINARY | F_PROGRESS));
  if (!fn || STRCMP(fn, ==, "-")) {
    m->fp = stdin;
    m->f |= F_NOCLOSE;
  } else if ((m->fp = fopen(fn, (f & F_BINARY) ? "rb" : "r")) == 0)
    die(EXIT_FAILURE, "couldn't open file `%s': %s", fn, strerror(errno));
  if (m->f & F_PROGRESS) {
    if (fprogress_init(&m->ff, fn, m->fp)) {
      die(EXIT_FAILURE, "failed to initialize progress indicator: %s",
	  strerror(errno));
    }
  }
  m->read = (f & F_BINARY) ? binreaddetach : textread;
}

static void mcsetup_writenull(msgcanon *m) { m->write = nullwrite; }

static void mcsetup_read(msgcanon *m, unsigned f, enc **ee,
			 const char *fn, const char *dfn)
{
  enc *e = *ee;

  m->f = f | F_NOCLOSE;

  if (dfn && !(f & F_DETACH)) die(EXIT_FAILURE, "signature is not detached");
  if (f & F_BINARY) {
    if (!(f & F_DETACH)) {
      m->e = e;
      *ee = 0;
      m->fp = e->fp;
      m->read = binreadembed;
      if (m->f & F_PROGRESS) {
	if (fprogress_init(&m->ff, fn, m->fp)) {
	  die(EXIT_FAILURE, "failed to initialize progress indicator: %s",
	      strerror(errno));
	}
      }
    } else {
      m->read = binreaddetach;
      if (!dfn || STRCMP(dfn, ==, "-"))
	m->fp = stdin;
      else if ((m->fp = fopen(dfn, "rb")) == 0)
	die(EXIT_FAILURE, "can't open `%s': %s", dfn, strerror(errno));
      else
	m->f &= ~F_NOCLOSE;
      if (m->f & F_PROGRESS) {
	if (fprogress_init(&m->ff, dfn, m->fp)) {
	  die(EXIT_FAILURE, "failed to initialize progress indicator: %s",
	      strerror(errno));
	}
      }
    }
  } else {
    m->read = textread;
    if (!(f & F_DETACH)) {
      if (e->ops->decdone(e) || ferror(e->fp))
	die(EXIT_FAILURE, "error at end of signature header");
      m->fp = e->fp;
      e->ops->destroy(e);
      *ee = 0;
      if (m->f & F_PROGRESS) {
	if (fprogress_init(&m->ff, fn, m->fp)) {
	  die(EXIT_FAILURE, "failed to initialize progress indicator: %s",
	      strerror(errno));
	}
      }
    } else {
      if (!dfn || STRCMP(dfn, ==, "-"))
	m->fp = stdin;
      else if ((m->fp = fopen(dfn, "r")) == 0)
	die(EXIT_FAILURE, "can't read file `%s': %s", dfn, strerror(errno));
      else
	m->f &= ~F_NOCLOSE;
      if (m->f & F_PROGRESS) {
	if (fprogress_init(&m->ff, dfn, m->fp)) {
	  die(EXIT_FAILURE, "failed to initialize progress indicator: %s",
	      strerror(errno));
	}
      }
    }
  }
}

static void mcsetup_write(msgcanon *m, unsigned f, enc **ee)
{
  enc *e = *ee;

  m->f = f | F_NOCLOSE;

  if (f & F_DETACH)
    m->write = nullwrite;
  else if (f & F_BINARY) {
    m->e = e;
    *ee = 0;
    m->fp = e->fp;
    m->write = binwriteembed;
  } else {
    if (e->ops->encdone(e) || ferror(e->fp))
      die(EXIT_FAILURE, "error at end of signature header");
    m->fp = e->fp;
    e->ops->destroy(e);
    *ee = 0;
    m->write = textwrite;
  }
}

static void mc_endread(msgcanon *m, const encops *eops, enc **ee)
{
  if (!(m->f & F_DETACH)) {
    if (m->f & F_BINARY)
      *ee = m->e;
    else
      *ee = initdec(eops, m->fp, checkbdry, "CATSIGN SIGNATURE");
  }
  if (m->fp && !(m->f & F_NOCLOSE)) {
    if (ferror(m->fp) || fclose(m->fp))
      die(EXIT_FAILURE, "error closing message file: %s", strerror(errno));
  }
  if (m->f & F_PROGRESS) fprogress_done(&m->ff);
}

static void mc_endwrite(msgcanon *m, const encops *eops, enc **ee)
{
  if (!(m->f & F_BINARY)) {
    if (m->f & F_MIDLINE) putc('\n', m->fp);
    if (!(m->f & F_DETACH)) {
      putc('.', m->fp); putc('\n', m->fp);
      *ee = initenc(eops, m->fp, "CATSIGN SIGNATURE");
    }
  } else if (!(m->f & F_DETACH)) {
    chunk_write(m->e, 0, 0);
    *ee = m->e;
  }
  if (m->fp && !(m->f & F_NOCLOSE)) {
    if (fflush(m->fp) || ferror(m->fp) || fclose(m->fp))
      die(EXIT_FAILURE, "error closing message file: %s", strerror(errno));
  }
}

/*----- Signature reading and writing -------------------------------------*/

static void sig_init(sigmsg *s, unsigned f, uint32 keyid)
{
  s->f = f & F_SIGMASK;
  s->keyid = keyid;
  time(&s->t);
  s->s = 0;
  dstr_create(&s->kh);
  dstr_create(&s->sig);
}

static void sig_destroy(sigmsg *s)
{
  dstr_destroy(&s->kh);
  dstr_destroy(&s->sig);
  if (s->s) freesig(s->s);
}

static void sigtobuffer(sigmsg *s, buf *b, int hashp)
{
  kludge64 t;

  ASSIGN64(t, s->t);
  if (hashp) buf_putu16(b, s->f & F_HASHMASK);
  else buf_putu16(b, s->f & F_SIGMASK);
  buf_putu32(b, s->keyid);
  buf_putu32(b, HI64(t));
  buf_putu32(b, LO64(t));
  buf_putdstr16(b, &s->kh);
  assert(BOK(b));
}

static void dohash(ghash *h, const void *p, size_t n)
{
  GH_HASH(h, p, n);
}

static void sig_hash(sigmsg *s)
{
  octet bb[16384];
  buf b;

  buf_init(&b, bb, sizeof(bb));
  sigtobuffer(s, &b, 1);
  dohash(s->s->h, BBASE(&b), BLEN(&b));
}

static void keyhash(key *k, sig *s, dstr *d)
{
  ghash *h;
  key_filter kf;

  h = GH_INIT(s->ch);
  kf.f = KCAT_PUB;
  kf.m = KF_CATMASK;
  key_fingerprint(k, h, &kf);
  dstr_ensure(d, GH_CLASS(h)->hashsz);
  GH_DONE(h, d->buf + d->len);
  d->len += GH_CLASS(h)->hashsz;
  GH_DESTROY(h);
}

static void sig_writeheader(enc *e, sigmsg *s)
{
  octet bb[16384];
  buf b;

  buf_init(&b, bb, sizeof(bb));
  sigtobuffer(s, &b, 0);
  chunk_write(e, BBASE(&b), BLEN(&b));
}

static void sig_writesig(enc *e, sigmsg *s)
  { chunk_write(e, s->sig.buf, s->sig.len); }

static void NORETURN diechoke(const char *m, void *p)
  { die(EXIT_FAILURE, "%s%s%s", (const char *)p, p ? ": " : "", m); }

static void sig_readheader(enc *e, sigmsg *s,
			   void NORETURN (*choke)(const char *, void *),
			   void *p)
{
  uint16 f;
  octet bb[MSGBUFSZ];
  uint32 x, y;
  kludge64 t;
  buf b;
  size_t n;

  n = chunk_read(e, bb);
  buf_init(&b, bb, n);
  if (buf_getu16(&b, &f)) choke("missing flags", p);
  if (buf_getu32(&b, &x)) choke("missing keyid", p);
  sig_init(s, f, x);
  if (buf_getu32(&b, &x) || buf_getu32(&b, &y))
    choke("missing datestamp", p);
  SET64(t, x, y); s->t = GET64(time_t, t);
  if (buf_getdstr16(&b, &s->kh))
    choke("missing key hash", p);
  if (BLEFT(&b))
    choke("junk at end", p);
}

static void sig_readsig(enc *e, sigmsg *s)
{
  octet bb[MSGBUFSZ];
  size_t n;

  n = chunk_read(e, bb);
  dstr_putm(&s->sig, bb, n);
}

/*----- Signing -----------------------------------------------------------*/

static int sign(int argc, char *argv[])
{
  const char *ef = "binary", *fn = 0, *of = 0, *kn = "ccsig", *err;
  unsigned f = 0;
  key_file kf;
  key *k;
  sigmsg s;
  FILE *ofp = 0;
  int i;
  char bb[MSGBUFSZ];
  size_t n;
  dstr d = DSTR_INIT;
  const encops *eo;
  msgcanon mc_in = MC_INIT, mc_out = MC_INIT;
  enc *e;

  for (;;) {
    static const struct option opt[] = {
      { "armour",	0,		0,	'a' },
      { "armor",	0,		0,	'a' },
      { "binary",	0,		0,	'b' },
      { "detach",	0,		0,	'd' },
      { "key",		OPTF_ARGREQ,	0,	'k' },
      { "format",	OPTF_ARGREQ,	0,	'f' },
      { "output",	OPTF_ARGREQ,	0,	'o' },
      { "progress",	0,		0,	'p' },
      { "text",		0,		0,	't' },
      { "nocheck",	0,		0,	'C' },
      { 0,		0,		0,	0 }
    };
    i = mdwopt(argc, argv, "k:f:o:abdptC", opt, 0, 0, 0);
    if (i < 0) break;
    switch (i) {
      case 'k': kn = optarg; break;
      case 'f': ef = optarg; break;
      case 'o': of = optarg; break;
      case 'a': ef = "pem"; break;
      case 't': f &= ~F_BINARY; break;
      case 'b': f |= F_BINARY; break;
      case 'd': f |= F_DETACH; break;
      case 'C': f |= F_NOCHECK; break;
      case 'p': f |= F_PROGRESS; break;
      default: f |= F_BOGUS; break;
    }
  }
  if (argc - optind > 1 || (f & F_BOGUS))
    die(EXIT_FAILURE, "Usage: sign [-OPTIONS] [FILE]");

  if (key_open(&kf, keyring, KOPEN_READ, key_moan, 0))
    die(EXIT_FAILURE, "can't open keyring `%s'", keyring);
  if ((k = key_bytag(&kf, kn)) == 0)
    die(EXIT_FAILURE, "key `%s' not found", kn);

  if ((eo = getenc(ef)) == 0)
    die(EXIT_FAILURE, "encoding `%s' not found", ef);

  fn = (optind >= argc) ? 0 : argv[optind++];

  if (!of || STRCMP(of, ==, "-"))
    ofp = stdout;
  else if ((ofp = fopen(of, eo->wmode)) == 0) {
    die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
	of, strerror(errno));
  }

  /* --- Start the work --- */

  sig_init(&s, f, k->id);
  dstr_reset(&d);
  key_fulltag(k, &d);
  s.s = getsig(k, "ccsig", 1);
  if (!(f & F_NOCHECK) && (err = s.s->ops->check(s.s)) != 0)
    moan("key %s fails check: %s", d.buf, err);
  keyhash(k, s.s, &s.kh);
  e = initenc(eo, ofp,
	      (f & F_DETACH) ? "CATSIGN SIGNATURE" :
	      (f & F_BINARY) ? "CATSIGN MESSAGE" :
	      "CATSIGN MESSAGE HEADER");
  sig_writeheader(e, &s);

  /* --- Hash the message --- */

  mcsetup_readfile(&mc_in, f, fn);
  mcsetup_write(&mc_out, f, &e);
  sig_hash(&s);
  for (;;) {
    n = mc_in.read(&mc_in, bb);
    if (!n) break;
    dohash(s.s->h, bb, n);
    mc_out.write(&mc_out, bb, n);
  }
  mc_endread(&mc_in, 0, 0);
  mc_endwrite(&mc_out, eo, &e);

  /* --- Write the signature --- */

  if (s.s->ops->doit(s.s, &s.sig))
    die(EXIT_FAILURE, "signature failed");
  sig_writesig(e, &s);
  e->ops->encdone(e);
  if (fflush(ofp) || ferror(ofp) || fclose(ofp))
    die(EXIT_FAILURE, "error writing signature: %s", strerror(errno));

  /* --- All done --- */

  freeenc(e);
  key_close(&kf);
  sig_destroy(&s);
  dstr_destroy(&d);
  return (0);
}

/*----- Verifying ---------------------------------------------------------*/

typedef struct vrfctx {
  unsigned f, m;
  int verb;
  const char *what;
} vrfctx;

static int vrfbdry(const char *b, void *p)
{
  vrfctx *v = p;

  if (STRCMP(b, ==, "CATSIGN MESSAGE")) {
    v->f |= F_BINARY;
    v->m |= F_BINARY | F_DETACH;
    return (1);
  } else if (STRCMP(b, ==, "CATSIGN MESSAGE HEADER")) {
    v->m |= F_BINARY | F_DETACH;
    return (1);
  } else if (STRCMP(b, ==, "CATSIGN SIGNATURE")) {
    v->f |= F_DETACH;
    v->m |= F_DETACH;
    return (1);
  } else
    return (0);
}

static void NORETURN vrfchoke(const char *m, void *p)
{
  vrfctx *v = p;
  if (v->verb) printf("FAIL %s: %s\n", v->what, m);
  exit(EXIT_FAILURE);
}

static int verify(int argc, char *argv[])
{
  const char *ef = "binary", *of = 0, *fn, *dfn = 0, *kn = 0, *err;
  vrfctx v = { 0, 0, 1 };
  key_file kf;
  key *k, *kk = 0;
  sigmsg s;
  FILE *fp, *ofp = 0, *rfp = 0;
  fprogress ff;
  struct tm *tm;
  int i;
  char bb[MSGBUFSZ];
  size_t n;
  time_t t_fresh = 0;
  dstr d = DSTR_INIT, dd = DSTR_INIT;
  const encops *eo;
  msgcanon mc_in = MC_INIT;
  enc *e;

  for (;;) {
    static const struct option opt[] = {
      { "armour",	0,		0,	'a' },
      { "armor",	0,		0,	'a' },
      { "buffer",	0,		0,	'b' },
      { "key",		OPTF_ARGREQ,	0,	'k' },
      { "format",	OPTF_ARGREQ,	0,	'f' },
      { "output",	OPTF_ARGREQ,	0,	'o' },
      { "progress",	0,		0,	'p' },
      { "quiet",	0,		0,	'q' },
      { "utc",		0,		0,	'u' },
      { "fresh-time",	0,		0,	't' },
      { "gmt",		0,		0,	'u' },
      { "verbose",	0,		0,	'v' },
      { "nocheck",	0,		0,	'C' },
      { 0,		0,		0,	0 }
    };
    i = mdwopt(argc, argv, "k:f:o:abpqt:uvC", opt, 0, 0, 0);
    if (i < 0) break;
    switch (i) {
      case 'a': ef = "pem"; break;
      case 'b': v.f |= F_BUFFER; break;
      case 'k': kn = optarg; break;
      case 'f': ef = optarg; break;
      case 'o': of = optarg; break;
      case 'u': v.f |= F_UTC; break;
      case 'C': v.f |= F_NOCHECK; break;
      case 't':
	if (STRCMP(optarg, ==, "always")) t_fresh = 0;
	else if ((t_fresh = get_date(optarg, 0)) < 0)
	  die(EXIT_FAILURE, "bad freshness time");
	break;
      case 'q': if (v.verb > 0) v.verb--; break;
      case 'v': if (v.verb < 10) v.verb++; break;
      case 'p': v.f |= F_PROGRESS; break;
      default: v.f |= F_BOGUS; break;
    }
  }
  if (argc - optind > 2 || (v.f & F_BOGUS))
    die(EXIT_FAILURE, "Usage: verify [-OPTIONS] [FILE [MESSAGE]]");

  if ((eo = getenc(ef)) == 0)
    die(EXIT_FAILURE, "encoding `%s' not found", ef);

  fn = optind < argc ? argv[optind++] : "-";
  if (STRCMP(fn, ==, "-"))
    fp = stdin;
  else if ((fp = fopen(fn, eo->rmode)) == 0) {
    die(EXIT_FAILURE, "couldn't open file `%s': %s",
	fn, strerror(errno));
  }

  if (key_open(&kf, keyring, KOPEN_READ, key_moan, 0))
    die(EXIT_FAILURE, "can't open keyring `%s'", keyring);
  if (kn && (kk = key_bytag(&kf, kn)) == 0)
    die(EXIT_FAILURE, "key `%s' not found", kn);

  e = initdec(eo, fp, vrfbdry, &v);

  /* --- Read the header chunk --- */

  v.what = "malformed header";
  sig_readheader(e, &s, vrfchoke, &v);

  if (((s.f ^ v.f) & v.m) != 0) {
    if (v.verb) printf("FAIL boundary string inconsistent with contents\n");
    exit(EXIT_FAILURE);
  }
  v.f |= s.f;

  if ((k = key_byid(&kf, s.keyid)) == 0) {
    if (v.verb) printf("FAIL key id %08lx not found\n",
		       (unsigned long)s.keyid);
    exit(EXIT_FAILURE);
  }
  if (kk && k != kk) {
    if (v.verb) {
      dstr_reset(&d); key_fulltag(k, &d);
      dstr_reset(&dd); key_fulltag(kk, &dd);
      printf("FAIL signing key is %s; expected key %s\n", d.buf, dd.buf);
    }
    exit(EXIT_FAILURE);
  }

  s.s = getsig(k, "ccsig", 0);
  dstr_reset(&d); key_fulltag(k, &d);
  if (!(v.f & F_NOCHECK) && v.verb && (err = s.s->ops->check(s.s)) != 0)
    printf("WARN verification key %s fails check: %s\n", d.buf, err);

  dstr_reset(&dd); keyhash(k, s.s, &dd);
  if (dd.len != s.kh.len || MEMCMP(dd.buf, !=, s.kh.buf, dd.len)) {
    if (v.verb) printf("FAIL key hash mismatch\n");
    exit(EXIT_FAILURE);
  }

  /* --- Now a merry dance --- */

  if (v.f & F_DETACH)
    sig_readsig(e, &s);
  if (optind < argc)
    dfn = argv[optind++];
  mcsetup_read(&mc_in, v.f, &e, fn, dfn);

  if (!of && (v.f & F_DETACH)) {
    rfp = ofp = 0;
    v.f &= ~F_BUFFER;
  } else if (!of || STRCMP(of, ==, "-")) {
    v.f |= F_BUFFER;
    ofp = stdout;
  } else if (of && !(v.f & F_BUFFER)) {
    if ((ofp = fopen(of, (v.f & F_BINARY) ? "wb" : "w")) == 0) {
      die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
	  of, strerror(errno));
    }
    rfp = ofp;
  }
  if ((v.f & F_BUFFER) && (rfp = tmpfile()) == 0)
    die(EXIT_FAILURE, "couldn't create temporary file: %s", strerror(errno));

  /* --- Read the message and verify the signature --- */

  sig_hash(&s);
  for (;;) {
    n = mc_in.read(&mc_in, bb);
    if (!n) break;
    dohash(s.s->h, bb, n);
    if (rfp) fwrite(bb, 1, n, rfp);
  }
  mc_endread(&mc_in, eo, &e);
  if (!(v.f & F_DETACH))
    sig_readsig(e, &s);
  if (rfp && (ferror(rfp) || fflush(rfp))) {
    if (v.verb) printf("FAIL error writing message: %s\n", strerror(errno));
    exit(EXIT_FAILURE);
  }

  /* --- Check the signature --- */

  if (s.s->ops->doit(s.s, &s.sig)) {
    if (v.verb) printf("FAIL signature verification failed\n");
    exit(EXIT_FAILURE);
  }
  if (t_fresh && s.t < t_fresh) {
    if (v.verb) printf("FAIL signature is stale\n");
    exit(EXIT_FAILURE);
  }
  if (s.t > time(0)) {
    if (v.verb) printf("FAIL signature timestamp in the future\n");
    exit(EXIT_FAILURE);
  }
  if (v.verb) {
    tm = (v.f & F_UTC) ? gmtime(&s.t) : localtime(&s.t);
    strftime(bb, sizeof(bb), "%Y-%m-%d %H:%M:%S %Z", tm);
    printf("INFO good-signature %s\n", d.buf);
    printf("INFO date %s\n", bb);
  }

  /* --- Unbuffer buffered input --- */

  if (v.f & F_BUFFER) {
    if (!ofp && (ofp = fopen(of, "wb")) == 0) {
      die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
	  of, strerror(errno));
    }
    rewind(rfp);
    if (v.f & F_PROGRESS) fprogress_init(&ff, "copying buffer", rfp);
    if (v.verb && ofp == stdout) printf("DATA\n");
    for (;;) {
      n = fread(bb, 1, sizeof(bb), rfp);
      if (!n) break;
      if (v.f & F_PROGRESS) fprogress_update(&ff, n);
      if (fwrite(bb, 1, n, ofp) < n) {
	if (v.f & F_PROGRESS) fprogress_done(&ff);
	die(EXIT_FAILURE, "error writing output: %s", strerror(errno));
      }
    }
    if (v.f & F_PROGRESS) fprogress_done(&ff);
    if (ferror(rfp) || fclose(rfp))
      die(EXIT_FAILURE, "error unbuffering output: %s", strerror(errno));
  }
  if (ofp && (fflush(ofp) || ferror(ofp) || fclose(ofp)))
      die(EXIT_FAILURE, "error writing output: %s", strerror(errno));

  /* --- Tidy up --- */

  e->ops->decdone(e);
  if (v.verb && ofp != stdout)
    printf("OK verified successfully\n");
  freeenc(e);
  key_close(&kf);
  sig_destroy(&s);
  dstr_destroy(&d);
  dstr_destroy(&dd);
  return (0);
}

/*----- Reformatting ------------------------------------------------------*/

static int format(int argc, char *argv[])
{
  const char *ief = "binary", *oef = "binary";
  const char *fn, *dfn = 0, *of = 0, *mf = 0;
  sigmsg s;
  FILE *fp, *ofp = 0, *mfp = 0;
  int i;
  size_t n;
  msgcanon mc_in = MC_INIT, mc_out = MC_INIT;
  char bb[MSGBUFSZ];
  vrfctx v = { 0, 0, 1 };
  unsigned f = 0, fm = ~F_SIGMASK, sf;
  const encops *ieo, *oeo;
  enc *ie, *oe;

  for (;;) {
    static const struct option opt[] = {
      { "armour-in",	0,		0,	'a' },
      { "armor-in",	0,		0,	'a' },
      { "armour-out",	0,		0,	'A' },
      { "armor-out",	0,		0,	'A' },
      { "detach",	0,		0,	'D' },
      { "embed",	0,		0,	'E' },
      { "format-in",	OPTF_ARGREQ,	0,	'f' },
      { "format-out",	OPTF_ARGREQ,	0,	'F' },
      { "message",	OPTF_ARGREQ,	0,	'm' },
      { "output",	OPTF_ARGREQ,	0,	'o' },
      { "progress",	0,		0,	'p' },
      { 0,		0,		0,	0 }
    };
    i = mdwopt(argc, argv, "f:F:m:o:apADE", opt, 0, 0, 0);
    if (i < 0) break;
    switch (i) {
      case 'a': ief = "pem"; break;
      case 'A': oef = "pem"; break;
      case 'f': ief = optarg; break;
      case 'F': oef = optarg; break;
      case 'D': f |= F_DETACH; fm |= F_DETACH; break;
      case 'E': f &= ~F_DETACH; fm |= F_DETACH; break;
      case 'm': mf = optarg; break;
      case 'o': of = optarg; break;
      case 'p': f |= F_PROGRESS; break;
      default: f |= F_BOGUS; break;
    }
  }

  if (argc - optind > 2 || (f & F_BOGUS))
    die(EXIT_FAILURE, "Usage: format [-OPTIONS] [FILE [MESSAGE]]");

  if ((ieo = getenc(ief)) == 0)
    die(EXIT_FAILURE, "encoding `%s' not found", ief);
  if ((oeo = getenc(oef)) == 0)
    die(EXIT_FAILURE, "encoding `%s' not found", oef);

  fn = optind < argc ? argv[optind++] : "-";
  if (STRCMP(fn, ==, "-"))
    fp = stdin;
  else if ((fp = fopen(fn, ieo->rmode)) == 0) {
    die(EXIT_FAILURE, "couldn't open file `%s': %s",
	fn, strerror(errno));
  }

  if (optind < argc)
    dfn = argv[optind++];

  ie = initdec(ieo, fp, vrfbdry, &v);

  /* --- Read the header chunk --- */

  sig_readheader(ie, &s, diechoke, "malformed header");

  if (((s.f ^ v.f) & v.m) != 0)
    moan("boundary string inconsistent with contents (ignoring)");

  mcsetup_read(&mc_in, s.f, &ie, fn, dfn);

  /* --- Prepare the output stuff --- */

  if (!of && !mf) of = "-";
  sf = s.f;
  f = (f & fm) | (s.f & ~fm);
  s.f = f & F_SIGMASK;

  if (sf & F_DETACH)
    sig_readsig(ie, &s);

  if (!of)
    mcsetup_writenull(&mc_out);
  else {
    if (STRCMP(of, ==, "-"))
      ofp = stdout;
    else if ((ofp = fopen(of, oeo->wmode)) == 0) {
      die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
	  of, strerror(errno));
    }
    oe = initenc(oeo, ofp,
		 (f & F_DETACH) ? "CATSIGN SIGNATURE" :
		 (f & F_BINARY) ? "CATSIGN MESSAGE" :
		 "CATSIGN MESSAGE HEADER");
    sig_writeheader(oe, &s);
    mcsetup_write(&mc_out, f, &oe);
  }

  if (mf) {
    if (STRCMP(mf, ==, "-"))
      mfp = stdout;
    else if ((mfp = fopen(mf, (f & F_BINARY) ? "wb" : "w")) == 0) {
      die(EXIT_FAILURE, "couldn't open file `%s' for output: %s",
	  mf, strerror(errno));
    }
  }

  /* --- Wade through the message body --- */

  for (;;) {
    n = mc_in.read(&mc_in, bb);
    if (!n) break;
    mc_out.write(&mc_out, bb, n);
    if (mfp) fwrite(bb, 1, n, mfp);
  }
  mc_endread(&mc_in, ieo, &ie);
  if (of) mc_endwrite(&mc_out, oeo, &oe);

  /* --- Write the signature --- */

  if (!(sf & F_DETACH))
    sig_readsig(ie, &s);
  if (of) {
    sig_writesig(oe, &s);
    oe->ops->encdone(oe);
  }

  /* --- All done --- */

  ie->ops->decdone(ie);
  if (ferror(fp) || fclose(fp))
    die(EXIT_FAILURE, "error reading input signature: %s", strerror(errno));
  if (ofp && (fflush(ofp) || ferror(ofp) || fclose(ofp)))
    die(EXIT_FAILURE, "error writing output signature: %s", strerror(errno));
  if (mfp && (fflush(mfp) || ferror(mfp) || fclose(mfp)))
    die(EXIT_FAILURE, "error writing output message: %s", strerror(errno));
  freeenc(ie);
  if (of) freeenc(oe);
  sig_destroy(&s);
  return (0);
}

static void NORETURN infochoke(const char *m, void *p)
{
  vrfctx *v = p;
  printf("BAD %s: %s\n", v->what, m);
  exit(EXIT_FAILURE);
}

static void infokeyreport(const char *file, int line,
			  const char *err, void *p)
{ /*whatever*/; }

static int info(int argc, char *argv[])
{
  const char *ef = "binary";
  vrfctx v = { 0, 0, 1 };
  key_file kf;
  key *k;
  sigmsg s;
  FILE *fp;
  int i;
  struct tm *tm;
  char bb[256];
  dstr d = DSTR_INIT;
  const encops *eo;
  enc *e;

  for (;;) {
    static const struct option opt[] = {
      { "armour",	0,		0,	'a' },
      { "armor",	0,		0,	'a' },
      { "format",	OPTF_ARGREQ,	0,	'f' },
      { "gmt",		0,		0,	'u' },
      { "utc",		0,		0,	'u' },
      { 0,		0,		0,	0 }
    };
    i = mdwopt(argc, argv, "f:au", opt, 0, 0, 0);
    if (i < 0) break;
    switch (i) {
      case 'a': ef = "pem"; break;
      case 'f': ef = optarg; break;
      case 'u': v.f |= F_UTC; break;
      default: v.f |= F_BOGUS; break;
    }
  }
  if (argc - optind > 1 || (v.f & F_BOGUS))
    die(EXIT_FAILURE, "Usage: info [-OPTIONS] [FILE]");

  if ((eo = getenc(ef)) == 0)
    die(EXIT_FAILURE, "encoding `%s' not found", ef);

  if (optind >= argc)
    fp = stdin;
  else if (STRCMP(argv[optind], ==, "-")) {
    fp = stdin;
    optind++;
  } else if ((fp = fopen(argv[optind], eo->rmode)) == 0) {
    die(EXIT_FAILURE, "couldn't open file `%s': %s",
	argv[optind], strerror(errno));
  } else
    optind++;

  if (key_open(&kf, keyring, KOPEN_READ, infokeyreport, 0)) {
    printf("NOTE can't open keyring `%s'\n", keyring);
    keyring = 0;
  }
  e = initdec(eo, fp, vrfbdry, &v);

  v.what = "malformed header";
  sig_readheader(e, &s, infochoke, &v);

  printf("INFO flags %sdetach %sbinary\n",
	 (s.f & F_DETACH) ? "" : "!",
	 (s.f & F_BINARY) ? "" : "!");

  if (((s.f ^ v.f) & v.m) != 0) {
    printf("WARN boundary string inconsistent with contents\n");
    printf("INFO expected-flags");
    if (v.m & F_DETACH) printf(" %sdetach", (v.f & F_DETACH) ? "" : "!");
    if (v.m & F_BINARY) printf(" %sbinary", (v.f & F_BINARY) ? "" : "!");
    putchar('\n');
  }
  v.f |= s.f;

  tm = (v.f & F_UTC) ? gmtime(&s.t) : localtime(&s.t);
  strftime(bb, sizeof(bb), "%Y-%m-%d %H:%M:%S %Z", tm);
  printf("INFO date %s\n", bb);

  if (keyring && (k = key_byid(&kf, s.keyid)) != 0) {
    dstr_reset(&d); key_fulltag(k, &d);
    printf("INFO key %s\n", d.buf);
  } else
    printf("INFO unknown-key %08lx\n", (unsigned long)s.keyid);

  if (keyring) key_close(&kf);
  dstr_destroy(&d);
  sig_destroy(&s);
  return (0);
}

/*----- Main code ---------------------------------------------------------*/

#define LISTS(LI)							\
  LI("Lists", list,							\
     listtab[i].name, listtab[i].name)					\
  LI("Signature schemes", sig,						\
     sigtab[i].name, sigtab[i].name)					\
  LI("Encodings", enc,							\
     enctab[i].name, enctab[i].name)					\
  LI("Hash functions", hash,						\
     ghashtab[i], ghashtab[i]->name)

MAKELISTTAB(listtab, LISTS)

int cmd_show(int argc, char *argv[])
{
  return (displaylists(listtab, argv + 1));
}

static int cmd_help(int, char **);

static cmd cmdtab[] = {
  { "help", cmd_help, "help [COMMAND...]" },
  { "show", cmd_show, "show [ITEM...]" },
  CMD_ENCODE,
  CMD_DECODE,
  { "sign", sign,
    "sign [-adptC] [-k TAG] [-f FORMAT] [-o OUTPUT] [FILE]", "\
Options:\n\
\n\
-a, --armour		Same as `-f pem'.\n\
-b, --binary		Treat the input message as binary data.\n\
-d, --detach		Produce a detached signature.\n\
-f, --format=FORMAT	Encode as FORMAT.\n\
-k, --key=TAG		Use public encryption key named by TAG.\n\
-o, --output=FILE	Write output to FILE.\n\
-p, --progress		Show progress on large files.\n\
-t, --text		Canonify input message as a text file.\n\
-C, --nocheck		Don't check the private key.\n\
" },
  { "verify", verify,
    "verify [-abpquvC] [-f FORMAT] [-k TAG] [-o OUTPUT]\n\t\
[FILE [MESSAGE]]", "\
Options:\n\
\n\
-a, --armour		Same as `-f pem'.\n\
-b, --buffer		Buffer message until signature is verified.\n\
-f, --format=FORMAT	Decode as FORMAT.\n\
-k, --key=TAG		Require that the message be signed by key TAG.\n\
-o, --output=FILE	Write message to FILE.\n\
-p, --progress		Show progress on large files.\n\
-q, --quiet		Produce fewer messages.\n\
-t, --freshtime=TIME	Only accept signatures made after this time.\n\
-u, --utc		Show dates in UTC rather than local time.\n\
-v, --verbose		Produce more verbose messages.\n\
-C, --nocheck		Don't check the public key.\n\
" },
  { "info", info,
    "info [-au] [-f FORMAT] [FILE]", "\
Options:\n\
\n\
-a, --armour		Same as `-f pem'.\n\
-f, --format=FORMAT	Decode as FORMAT.\n\
-u, --utc		Show dates in UTC rather than local time.\n\
"},
  { "format", format,
    "format [-apuADE] [-f FORMAT] [-F format] [-m FILE] [-o FILE]\n\t\
[FILE [MESSAGE]]", "\
Options:\n\
\n\
-a, --armour-in		Same as `-f pem'.\n\
-A, --armour-out	Same as `-F pem'.\n\
-D, --detach		Create detached signature.\n\
-E, --embed		Create signature with embedded message.\n\
-f, --format-in=FORMAT	Decode input as FORMAT.\n\
-F, --format-out=FORMAT	Encode output as FORMAT.\n\
-m, --message=FILE	Write message to FILE.\n\
-o, --output=FILE	Write new signature to FILE.\n\
-p, --progress		Show progress on large files.\n\
"},
  { 0, 0, 0 }
}; /* " Emacs seems confused. */

static int cmd_help(int argc, char **argv)
{
  sc_help(cmdtab, stdout, argv + 1);
  return (0);
}

void version(FILE *fp)
{
  pquis(fp, "$, Catacomb version " VERSION "\n");
}

static void usage(FILE *fp)
{
  pquis(fp, "Usage: $ [-k KEYRING] COMMAND [ARGS]\n");
}

void help_global(FILE *fp)
{
  usage(fp);
  fputs("\n\
Sign and verify data.\n\
\n\
Global command-line options:\n\
\n\
-h, --help [COMMAND...]	Show this help message, or help for COMMANDs.\n\
-v, --version		Show program version number.\n\
-u, --usage		Show a terse usage message.\n\
\n\
-k, --keyring=FILE	Read keys from FILE.\n",
	fp);
}

/* --- @main@ --- *
 *
 * Arguments:	@int argc@ = number of command line arguments
 *		@char *argv[]@ = vector of command line arguments
 *
 * Returns:	Zero if successful, nonzero otherwise.
 *
 * Use:		Encrypts or decrypts files.
 */

int main(int argc, char *argv[])
{
  unsigned f = 0;

#define f_bogus 1u

  /* --- Initialize the library --- */

  ego(argv[0]);
  sub_init();
  rand_noisesrc(RAND_GLOBAL, &noise_source);
  rand_seed(RAND_GLOBAL, 160);

  /* --- Parse options --- */

  for (;;) {
    static struct option opts[] = {
      { "help",		0,		0,	'h' },
      { "version",	0,		0,	'v' },
      { "usage",	0,		0,	'u' },
      { "keyring",	OPTF_ARGREQ,	0,	'k' },
      { 0,		0,		0,	0 }
    };
    int i = mdwopt(argc, argv, "+hvu k:", opts, 0, 0, 0);
    if (i < 0)
      break;
    switch (i) {
      case 'h':
	sc_help(cmdtab, stdout, argv + optind);
	exit(0);
	break;
      case 'v':
	version(stdout);
	exit(0);
	break;
      case 'u':
	usage(stdout);
	exit(0);
      case 'k':
	keyring = optarg;
	break;
      default:
	f |= f_bogus;
	break;
    }
  }

  argc -= optind;
  argv += optind;
  optind = 0;
  if (f & f_bogus || argc < 1) {
    usage(stderr);
    exit(EXIT_FAILURE);
  }

  /* --- Dispatch to the correct subcommand handler --- */

  return (findcmd(cmdtab, argv[0])->cmd(argc, argv));

#undef f_bogus
}

/*----- That's all, folks -------------------------------------------------*/