cc-hash.c: New file containing hash-related code from hashsum and dsig.

[u/mdw/catacomb] / hashsum.c

/* -*-c-*-
 *
 * $Id$
 *
 * Hash files using some secure hash function
 *
 * (c) 2000 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 <assert.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <mLib/alloc.h>
#include <mLib/dstr.h>
#include <mLib/mdwopt.h>
#include <mLib/quis.h>
#include <mLib/report.h>
#include <mLib/sub.h>
#include <mLib/str.h>

#include "ghash.h"
#include "cc.h"

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

#define f_bogus 1u
#define f_verbose 2u
#define f_check 4u
#define f_files 8u
#define f_oddhash 16u
#define f_escape 32u
#define f_oddenc 64u

/*----- Support functions -------------------------------------------------*/

/* --- @gethash@ --- *
 *
 * Arguments:	@const char *name@ = pointer to name string
 *
 * Returns:	Pointer to appropriate hash class.
 *
 * Use:		Chooses a hash function by name.
 */

static const gchash *gethash(const char *name)
{
  const gchash *const *g, *gg = 0;
  size_t sz = strlen(name);
  for (g = ghashtab; *g; g++) {
    if (strncmp(name, (*g)->name, sz) == 0) {
      if ((*g)->name[sz] == 0) {
	gg = *g;
	break;
      } else if (gg)
	return (0);
      else
	gg = *g;
    }
  }
  return (gg);
}

/*----- Guts --------------------------------------------------------------*/

static int checkhash(const gchash *gch, unsigned f,
		     const char *file, const encodeops *e)
{
  int rc;
  FILE *fp;
  dstr d = DSTR_INIT;
  dstr dd = DSTR_INIT;
  unsigned long n = 0, nfail = 0;
  octet *buf = xmalloc(2 * gch->hashsz);

  if (!file || strcmp(file, "-") == 0)
    fp = stdin;
  else if ((fp = fopen(file, f & GSF_RAW ? "r" : "rb")) == 0) {
    moan("couldn't open `%s': %s", file, strerror(errno));
    return (EXIT_FAILURE);
  }

  while (DRESET(&d), dstr_putline(&d, fp) != EOF) {
    char *p = d.buf;
    char *q;
    unsigned ff = f;

    /* --- Handle a directive --- */

    if (*p == '#') {
      p++;
      if ((q = str_getword(&p)) == 0)
	continue;
      if (strcmp(q, "hash") == 0) {
	const gchash *g;
	if ((q = str_getword(&p)) == 0)
	  continue;
	if ((g = gethash(q)) == 0)
	  continue;
	gch = g;
	xfree(buf);
	buf = xmalloc(2 * gch->hashsz);
      } else if (strcmp(q, "encoding") == 0) {
	const encodeops *ee;
	if ((q = str_getword(&p)) == 0)
	  continue;
	if ((ee = getencoding(q)) == 0)
	  continue;
	e = ee;
      } else if (strcmp(q, "escape") == 0)
	f |= f_escape;
      continue;
    }

    /* --- Otherwise it's a hex thing --- */

    q = p;
    while (*p && *p != ' ')
      p++;
    if (!*p)
      continue;
    *p++ = 0;
    if (e->get(q, buf, gch->hashsz, 0) < gch->hashsz)
      continue;
    if (*p == '*')
      ff |= FHF_BINARY;
    else if (*p != ' ')
      continue;
    p++;

    if (f & f_escape) {
      DRESET(&dd);
      getstring(&p, &dd, GSF_STRING);
      p = dd.buf;
    }

    if (fhash(gch, ff, p, buf + gch->hashsz)) {
      moan("couldn't read `%s': %s", p, strerror(errno));
      rc = EXIT_FAILURE;
      continue;
    }
    if (memcmp(buf, buf + gch->hashsz, gch->hashsz) != 0) {
      if (ff & f_verbose)
	fprintf(stderr, "FAIL %s\n", p);
      else
	moan("%s check failed for `%s'", gch->name, p);
      nfail++;
      rc = EXIT_FAILURE;
    } else {
      if (ff & f_verbose)
	fprintf(stderr, "OK %s\n", p);
    }
    n++;
  }

  dstr_destroy(&d);
  dstr_destroy(&dd);
  xfree(buf);
  if ((f & f_verbose) && nfail)
    moan("%lu of %lu file(s) failed %s check", nfail, n, gch->name);
  else if (!n)
    moan("no files checked");
  return (0);
}

static int dohash(const gchash *gch, unsigned f,
		  const char *file, const encodeops *e)
{
  int rc = 0;
  octet *p = xmalloc(gch->hashsz);

  if (fhash(gch, f, file, p)) {
    moan("couldn't read `%s': %s", file ? file : "<stdin>", strerror(errno));
    rc = EXIT_FAILURE;
  } else {
    e->put(p, gch->hashsz, stdout);
    if (file) {
      fputc(' ', stdout);
      fputc(f & FHF_BINARY ? '*' : ' ', stdout);
      if (f & f_escape)
	putstring(stdout, file, 0);
      else
	fputs(file, stdout);
    }
    fputc('\n', stdout);
  }

  xfree(p);
  return (rc);
}

static int dofile(const gchash *gch, unsigned f,
		  const char *file, const encodeops *e)
  { return (f & f_check ? checkhash : dohash)(gch, f, file, e); }

static int hashfiles(const gchash *gch, unsigned f,
		     const char *file, const encodeops *e)
{
  FILE *fp;
  dstr d = DSTR_INIT;
  int rc = 0;
  int rrc;

  if (!file || strcmp(file, "-") == 0)
    fp = stdin;
  else if ((fp = fopen(file, f & GSF_RAW ? "r" : "rb")) == 0) {
    moan("couldn't open `%s': %s", file, strerror(errno));
    return (EXIT_FAILURE);
  }

  for (;;) {
    DRESET(&d);
    if (getstring(fp, &d, GSF_FILE | f))
      break;
    if ((rrc = dofile(gch, f, d.buf, e)) != 0)
      rc = rrc;
  }

  return (rc);
}

static int hashsum(const gchash *gch, unsigned f,
		   const char *file, const encodeops *e)
  { return (f & f_files ? hashfiles : dofile)(gch, f, file, e); }

/*----- Main driver -------------------------------------------------------*/

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

static void usage(FILE *fp)
{
  pquis(fp, "Usage: $ [-f0ebcv] [-a ALGORITHM] [-E ENC] [FILES...]\n");
}

static void help(FILE *fp, const gchash *gch)
{
  version(fp);
  fputc('\n', fp);
  usage(fp);
  pquis(fp, "\n\
Generates or checks message digests on files.  Options available:\n\
\n\
-h, --help		Display this help message.\n\
-V, --version		Display program's version number.\n\
-u, --usage		Display a terse usage message.\n\
-l, --list [ITEM...]	Show known hash functions and/or encodings.\n\
\n\
-a, --algorithm=ALG	Use the message digest algorithm ALG.\n\
-E, --encoding=ENC	Represent hashes using encoding ENC.\n\
\n\
-f, --files		Read a list of file names from standard input.\n\
-0, --null		File names are null terminated, not plain text.\n\
\n\
-e, --escape		Escape funny characters in filenames.\n\
-c, --check		Check message digests rather than emitting them.\n\
-b, --binary		When reading files, treat them as binary.\n\
-v, --verbose		Be verbose when checking digests.\n\
\n\
For a list of hashing algorithms and encodings, type `$ --list'.\n\
");
  if (gch)
    fprintf(fp, "The default message digest algorithm is %s.\n", gch->name);
}

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

MAKELISTTAB(listtab, LISTS)

int main(int argc, char *argv[])
{
  unsigned f = 0;
  const gchash *gch = 0;
  const encodeops *e = &encodingtab[0];
  int rc;

  /* --- Initialization --- */

  ego(argv[0]);
  sub_init();

  /* --- Choose a hash function from the name --- */

  {
    char *q = xstrdup(QUIS);
    size_t len = strlen(q);
    if (len > 3 && strcmp(q + len - 3, "sum") == 0) {
      q[len - 3] = 0;
      gch = gethash(q);
    }
    if (!gch)
      gch = gethash("md5");
    xfree(q);
  }

  /* --- Read options --- */

  for (;;) {
    static struct option opts[] = {
      { "help",		0,		0,	'h' },
      { "verbose",	0,		0,	'V' },
      { "usage",	0,		0,	'u' },

      { "algorithm",	OPTF_ARGREQ,	0,	'a' },
      { "hash",		OPTF_ARGREQ,	0,	'a' },
      { "encoding",	OPTF_ARGREQ,	0,	'E' },
      { "list",		0,		0,	'l' },

      { "files",	0,		0,	'f' },
      { "find",		0,		0,	'f' },
      { "null",		0,		0,	'0' },

      { "escape",	0,		0,	'e' },
      { "check",	0,		0,	'c' },
      { "binary",	0,		0,	'b' },
      { "verbose",	0,		0,	'v' },
      { "progress",	0,		0,	'p' },

      { 0,		0,		0,	0 }
    };
    int i = mdwopt(argc, argv, "hVu a:E:l f0 ecbvp", opts, 0, 0, 0);
    if (i < 0)
      break;

    switch (i) {
      case 'h':
	help(stdout, gch);
	exit(0);
      case 'V':
	version(stdout);
	exit(0);
      case 'u':
	usage(stdout);
	exit(0);
      case 'l':
	exit(displaylists(listtab, argv + optind));
      case 'a':
	if ((gch = gethash(optarg)) == 0)
	  die(EXIT_FAILURE, "unknown hash algorithm `%s'", optarg);
	f |= f_oddhash;
	break;
      case 'E':
	if ((e = getencoding(optarg)) == 0)
	  die(EXIT_FAILURE, "unknown encoding `%s'", optarg);
	f |= f_oddenc;
	break;
      case 'f':
	f |= f_files;
	break;
      case '0':
	f |= GSF_RAW;
	break;
      case 'e':
	f |= f_escape;
	break;
      case 'c':
	f |= f_check;
	break;
      case 'b':
	f |= FHF_BINARY;
	break;
      case 'v':
	f |= f_verbose;
	break;
      case 'p':
	f |= FHF_PROGRESS;
	break;
      default:
	f |= f_bogus;
	break;
    }
  }

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

  /* --- Generate output --- */

  if (!(f & f_check) && (argc || (f & f_files))) {
    if (f & f_oddhash) printf("#hash %s\n", gch->name);
    if (f & f_oddenc) printf("#encoding %s\n", e->name);
    if (f & f_escape) fputs("#escape\n", stdout);
  }
  if (!argc)
    rc = hashsum(gch, f, 0, e);
  else {
    int i;
    int rrc;

    rc = 0;
    for (i = 0; i < argc; i++) {
      if ((rrc = hashsum(gch, f, argv[i], e)) != 0)
	rc = rrc;
    }
  }

  return (rc);
}

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