/* cli.c
* Greg Cook, 23/Feb/2019
*/
/* CRC RevEng: arbitrary-precision CRC calculator and algorithm finder
* Copyright (C) 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018,
* 2019 Gregory Cook
*
* This file is part of CRC RevEng.
*
* CRC RevEng is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* CRC RevEng 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with CRC RevEng. If not, see <https://www.gnu.org/licenses/>.
*/
/* 2018-07-26: NOFORCE renamed ALWPCK
* 2017-02-18: -G ignored if R_HAVEP
* 2017-02-05: added -G
* 2016-06-27: -P sets width like -k
* 2015-04-03: added -z
* 2013-09-16: do not search with -M
* 2013-06-11: uprog() suppresses first progress report
* 2013-04-22: uprog() prints poly same as mtostr()
* 2013-02-07: added -q, uprog(), removed -W, R_ODDLY
* 2012-05-24: -D dumps parameters of all models
* 2012-03-03: added code to test sort order of model table
* 2012-02-20: set stdin to binary (MinGW). offer -D if preset unknown.
* 2011-09-06: -s reads arguments once. stdin not closed.
* 2011-09-06: fixed bad argument-freeing loops.
* 2011-08-27: validates BMP_C()
* 2011-08-26: validates BMPBIT and BMPSUB
* 2011-08-25: fixed Init/Xorout reflection logic in -V and -v
* 2011-01-17: fixed ANSI C warnings
* 2011-01-15: added NOFORCE
* 2011-01-14: added -k, -P
* 2011-01-10: reorganised switches, added -V, -X
* 2010-12-26: renamed CRC RevEng
* 2010-12-18: implemented -c, -C
* 2010-12-14: added and implemented -d, -D, fixed -ipx entry
* 2010-12-11: implemented -e. first tests
* 2010-12-10: finalised option processing. started input validation
* 2010-12-07: started cli
*/
#include <stdio.h>
#include <stdlib.h>
#include "cliparser/getopt.h"
#ifdef _WIN32
# include <io.h>
# include <fcntl.h>
# ifndef STDIN_FILENO
# define STDIN_FILENO 0
# endif /* STDIN_FILENO */
#endif /* _WIN32 */
#include "reveng.h"
static FILE *oread(const char *);
static poly_t rdpoly(const char *, int, int);
static void usage(void);
static const char *myname = "reveng"; /* name of our program */
int reveng_main(int argc, char *argv[]) {
/* Command-line interface for CRC RevEng.
* Process options and switches in the argument list and
* run the required function.
*/
/* default values */
model_t model = MZERO;
int ibperhx = 8, obperhx = 8;
int rflags = 0, uflags = 0; /* search and UI flags */
unsigned long width = 0UL;
int c, mode = 0, args, psets, pass;
poly_t apoly, crc, qpoly = PZERO, *apolys, *pptr = NULL, *qptr = NULL;
model_t pset = model, *candmods, *mptr;
char *string;
myname = argv[0];
/* stdin must be binary */
#ifdef _WIN32
_setmode(STDIN_FILENO, _O_BINARY);
#endif /* _WIN32 */
SETBMP();
// pos=0; --- not in this ver of getopt
optind = 1;
do {
c = getopt(argc, argv, "?A:BDFGLMP:SVXa:bcdefhi:k:lm:p:q:rstuvw:x:yz");
switch (c) {
case 'A': /* A: bits per output character */
case 'a': /* a: bits per character */
if ((obperhx = atoi(optarg)) > BMP_BIT) {
fprintf(stderr, "%s: argument to -%c must be between 1 and %d\n", myname, c, BMP_BIT);
return 0;
//exit(EXIT_FAILURE);
}
if (c == 'a') ibperhx = obperhx;
break;
case 'b': /* b big-endian (RefIn = false, RefOut = false ) */
model.flags &= ~P_REFIN;
rflags |= R_HAVERI;
/* fall through: */
case 'B': /* B big-endian output (RefOut = false) */
model.flags &= ~P_REFOUT;
rflags |= R_HAVERO;
mnovel(&model);
/* fall through: */
case 'r': /* r right-justified */
model.flags |= P_RTJUST;
break;
case 'c': /* c calculate CRC */
case 'D': /* D list primary model names */
case 'd': /* d dump CRC model */
case 'e': /* e echo arguments */
case 's': /* s search for algorithm */
case 'v': /* v calculate reversed CRC */
if (mode) {
fprintf(stderr, "%s: more than one mode switch specified. Use %s -h for help.\n", myname, myname);
return 0;
//exit(EXIT_FAILURE);
}
mode = c;
break;
case 'F': /* F skip preset model check pass */
#ifndef ALWPCK
uflags |= C_NOPCK;
#endif
break;
case 'f': /* f arguments are filenames */
uflags |= C_INFILE;
break;
case 'G': /* G skip brute force search pass */
uflags |= C_NOBFS;
break;
case 'h': /* h get help / usage */
case 'u': /* u get help / usage */
case '?': /* ? get help / usage */
default:
usage();
return 0;
//exit(EXIT_FAILURE);
break;
case 'i': /* i: Init value */
pptr = &model.init;
rflags |= R_HAVEI;
goto ipqx;
case 'k': /* k: polynomial in Koopman notation */
case 'P': /* P: reversed polynomial */
pfree(&model.spoly);
model.spoly = strtop(optarg, 0, 4);
pkchop(&model.spoly);
width = plen(model.spoly);
rflags |= R_HAVEP;
if (c == 'P')
prcp(&model.spoly);
mnovel(&model);
break;
case 'l': /* l little-endian input and output */
model.flags |= P_REFIN;
rflags |= R_HAVERI;
/* fall through: */
case 'L': /* L little-endian output */
model.flags |= P_REFOUT;
rflags |= R_HAVERO;
mnovel(&model);
/* fall through: */
case 't': /* t left-justified */
model.flags &= ~P_RTJUST;
break;
case 'm': /* m: select preset CRC model */
if (!(c = mbynam(&model, optarg))) {
fprintf(stderr, "%s: preset model '%s' not found. Use %s -D to list presets.\n", myname, optarg, myname);
return 0;
//exit(EXIT_FAILURE);
}
if (c < 0) {
uerror("no preset models available");
return 0;
}
/* must set width so that parameter to -ipx is not zeroed */
width = plen(model.spoly);
rflags |= R_HAVEP | R_HAVEI | R_HAVERI | R_HAVERO | R_HAVEX;
break;
case 'M': /* M non-augmenting algorithm */
model.flags &= ~P_MULXN;
break;
case 'p': /* p: polynomial */
pptr = &model.spoly;
rflags &= ~R_HAVEQ;
rflags |= R_HAVEP;
ipqx:
pfree(pptr);
*pptr = strtop(optarg, 0, 4);
pright(pptr, width);
mnovel(&model);
break;
case 'q': /* q: range end polynomial */
pptr = &qpoly;
rflags &= ~R_HAVEP;
rflags |= R_HAVEQ;
goto ipqx;
case 'S': /* s space between output characters */
model.flags |= P_SPACE;
break;
case 'V': /* v reverse algorithm */
/* Distinct from the -v switch as the
* user will have to reverse his or her
* own arguments. The user cannot dump
* the model generated by -v either.
*/
mrev(&model);
break;
case 'w': /* w: CRC width = order - 1 */
/* no validation, WONTFIX */
width = (unsigned long) atol(optarg);
break;
case 'X': /* X print uppercase hex */
model.flags |= P_UPPER;
break;
case 'x': /* x: XorOut value */
pptr = &model.xorout;
rflags |= R_HAVEX;
goto ipqx;
case 'y': /* y little-endian byte order in files */
model.flags |= P_LTLBYT;
break;
case 'z': /* z raw binary arguments */
model.flags |= P_DIRECT;
break;
case -1: /* no more options, continue */
;
}
} while (c != -1);
/* canonicalise the model, so the one we dump is the one we
* calculate with (not with -s, spoly may be blank which will
* normalise to zero and clear init and xorout.)
*/
if (mode != 's')
mcanon(&model);
switch (mode) {
case 'v': /* v calculate reversed CRC */
/* Distinct from the -V switch as this causes
* the arguments and output to be reversed as well.
*/
/* reciprocate Poly */
prcp(&model.spoly);
/* mrev() does:
* if(refout) prev(init); else prev(xorout);
* but here the entire argument polynomial is
* reflected, not just the characters, so RefIn
* and RefOut are not inverted as with -V.
* Consequently Init is the mirror image of the
* one resulting from -V, and so we have:
*/
if (~model.flags & P_REFOUT) {
prev(&model.init);
prev(&model.xorout);
}
/* swap init and xorout */
apoly = model.init;
model.init = model.xorout;
model.xorout = apoly;
/* fall through: */
case 'c': /* c calculate CRC */
/* validate inputs */
/* if(plen(model.spoly) == 0) {
* fprintf(stderr,"%s: no polynomial specified for -%c (add -w WIDTH -p POLY)\n", myname, mode);
* exit(EXIT_FAILURE);
* }
*/
/* in the Williams model, xorout is applied after the refout stage.
* as refout is part of ptostr(), we reverse xorout here.
*/
if (model.flags & P_REFOUT)
prev(&model.xorout);
for (; optind < argc; ++optind) {
if (uflags & C_INFILE)
apoly = rdpoly(argv[optind], model.flags, ibperhx);
else
apoly = strtop(argv[optind], model.flags, ibperhx);
if (mode == 'v')
prev(&apoly);
crc = pcrc(apoly, model.spoly, model.init, model.xorout, model.flags);
if (mode == 'v')
prev(&crc);
string = ptostr(crc, model.flags, obperhx);
puts(string);
free(string);
pfree(&crc);
pfree(&apoly);
}
break;
case 'D': /* D dump all models */
args = mcount();
if (!args) {
uerror("no preset models available");
return 0;
}
do {
mbynum(&model, --args);
ufound(&model);
} while (args);
break;
case 'd': /* d dump CRC model */
/* maybe we don't want to do this:
* either attaching names to arbitrary models or forcing to a preset
* mmatch(&model, M_OVERWR);
*/
if (~model.flags & P_MULXN) {
uerror("not a Williams model compliant algorithm");
return 0;
}
string = mtostr(&model);
puts(string);
free(string);
break;
case 'e': /* e echo arguments */
for (; optind < argc; ++optind) {
if (uflags & C_INFILE)
apoly = rdpoly(argv[optind], model.flags, ibperhx);
else
apoly = strtop(argv[optind], model.flags, ibperhx);
psum(&apoly, model.init, 0UL);
string = ptostr(apoly, model.flags, obperhx);
puts(string);
free(string);
pfree(&apoly);
}
break;
case 's': /* s search for algorithm */
if (!width) {
uerror("must specify positive -k or -w before -s");
return 0;
}
if (~model.flags & P_MULXN) {
uerror("cannot search for non-Williams compliant models");
return 0;
}
praloc(&model.spoly, width);
praloc(&model.init, width);
praloc(&model.xorout, width);
if (!plen(model.spoly))
palloc(&model.spoly, width);
else
width = plen(model.spoly);
/* special case if qpoly is zero, search to end of range */
if (!ptst(qpoly))
rflags &= ~R_HAVEQ;
/* allocate argument array */
args = argc - optind;
apolys = calloc(args * sizeof(poly_t), sizeof(char));
if (!apolys) {
uerror("cannot allocate memory for argument list");
return 0;
}
for (pptr = apolys; optind < argc; ++optind) {
if (uflags & C_INFILE)
*pptr++ = rdpoly(argv[optind], model.flags, ibperhx);
else
*pptr++ = strtop(argv[optind], model.flags, ibperhx);
}
/* exit value of pptr is used hereafter! */
/* if endianness not specified, try
* little-endian then big-endian.
* NB: crossed-endian algorithms will not be
* searched.
*/
/* scan against preset models */
if (~uflags & C_NOPCK) {
pass = 0;
do {
psets = mcount();
while (psets) {
mbynum(&pset, --psets);
/* skip if different width, or refin or refout don't match */
if (plen(pset.spoly) != width || (model.flags ^ pset.flags) & (P_REFIN | P_REFOUT))
continue;
/* skip if the preset doesn't match specified parameters */
if (rflags & R_HAVEP && pcmp(&model.spoly, &pset.spoly))
continue;
if (rflags & R_HAVEI && psncmp(&model.init, &pset.init))
continue;
if (rflags & R_HAVEX && psncmp(&model.xorout, &pset.xorout))
continue;
apoly = pclone(pset.xorout);
if (pset.flags & P_REFOUT)
prev(&apoly);
for (qptr = apolys; qptr < pptr; ++qptr) {
crc = pcrc(*qptr, pset.spoly, pset.init, apoly, 0);
if (ptst(crc)) {
pfree(&crc);
break;
} else
pfree(&crc);
}
pfree(&apoly);
if (qptr == pptr) {
/* the selected model solved all arguments */
ufound(&pset);
uflags |= C_RESULT;
}
}
mfree(&pset);
/* toggle refIn/refOut and reflect arguments */
if (~rflags & R_HAVERI) {
model.flags ^= P_REFIN | P_REFOUT;
for (qptr = apolys; qptr < pptr; ++qptr)
prevch(qptr, ibperhx);
}
} while (~rflags & R_HAVERI && ++pass < 2);
}
if (uflags & C_RESULT) {
for (qptr = apolys; qptr < pptr; ++qptr)
pfree(qptr);
return 1;
//exit(EXIT_SUCCESS);
}
if (uflags & C_NOBFS && ~rflags & R_HAVEP) {
uerror("no models found");
return 0;
//break;
}
if (!(model.flags & P_REFIN) != !(model.flags & P_REFOUT)) {
uerror("cannot search for crossed-endian models");
return 0;
}
pass = 0;
do {
mptr = candmods = reveng(&model, qpoly, rflags, args, apolys);
if (mptr && plen(mptr->spoly))
uflags |= C_RESULT;
while (mptr && plen(mptr->spoly)) {
/* results were printed by the callback
* string = mtostr(mptr);
* puts(string);
* free(string);
*/
mfree(mptr++);
}
free(candmods);
if (~rflags & R_HAVERI) {
model.flags ^= P_REFIN | P_REFOUT;
for (qptr = apolys; qptr < pptr; ++qptr)
prevch(qptr, ibperhx);
}
} while (~rflags & R_HAVERI && ++pass < 2);
for (qptr = apolys; qptr < pptr; ++qptr)
pfree(qptr);
free(apolys);
if (~uflags & C_RESULT)
uerror("no models found");
break;
default: /* no mode specified */
fprintf(stderr, "%s: no mode switch specified. Use %s -h for help.\n", myname, myname);
return 0;
//exit(EXIT_FAILURE);
}
return 1;
//exit(EXIT_SUCCESS);
}
void
ufound(const model_t *model) {
/* Callback function to report each model found */
char *string;
if (!model) return;
/* generated models will be canonical */
string = mtostr(model);
puts(string);
free(string);
}
void
uerror(const char *msg) {
/* Callback function to report fatal errors */
fprintf(stderr, "%s: %s\n", myname, msg);
//exit(EXIT_FAILURE);
}
void
uprog(const poly_t gpoly, int flags, unsigned long seq) {
/* Callback function to report search progress */
char *string;
/* Suppress first report in CLI */
if (!seq)
return;
string = ptostr(gpoly, P_RTJUST, 4);
fprintf(stderr, "%s: searching: width=%lu poly=0x%s refin=%s refout=%s\n",
myname,
plen(gpoly),
string,
((flags & P_REFIN) ? "true" : "false"),
((flags & P_REFOUT) ? "true" : "false")
);
free(string);
}
static poly_t
rdpoly(const char *name, int flags, int bperhx) {
/* read poly from file in chunks and report errors */
poly_t apoly = PZERO, chunk;
FILE *input;
input = oread(name);
while (!feof(input) && !ferror(input)) {
chunk = filtop(input, BUFFER, flags, bperhx);
psum(&apoly, chunk, plen(apoly));
pfree(&chunk);
}
if (ferror(input)) {
fprintf(stderr, "%s: error condition on file '%s'\n", myname, name);
exit(EXIT_FAILURE);
}
/* close file unless stdin */
if (input == stdin)
/* reset EOF condition */
clearerr(input);
else if (fclose(input)) {
fprintf(stderr, "%s: error closing file '%s'\n", myname, name);
exit(EXIT_FAILURE);
}
return (apoly);
}
static FILE *
oread(const char *name) {
/* open file for reading and report errors */
FILE *handle;
/* recognise special name '-' as standard input */
if (*name == '-' && name[1] == '\0')
return (stdin);
if (!(handle = fopen(name, "rb"))) {
fprintf(stderr, "%s: cannot open '%s' for reading\n", myname, name);
return 0;
//exit(EXIT_FAILURE);
}
return (handle);
}
static void
usage(void) {
/* print usage if asked, or if syntax incorrect */
fprintf(stderr,
"CRC RevEng: arbitrary-precision CRC calculator and algorithm finder\n"
"Usage:\t");
fputs(myname, stderr);
fprintf(stderr,
"\t-cdDesvhu? [-bBfFGlLMrStVXyz]\n"
"\t\t[-a BITS] [-A OBITS] [-i INIT] [-k KPOLY] [-m MODEL] [-p POLY]\n"
"\t\t[-p POLY] [-P RPOLY] [-q QPOLY] [-w WIDTH] [-x XOROUT] [STRING...]\n"
"Options:\n"
"\t-a BITS\t\tbits per character (1 to %d)\n"
"\t-A OBITS\tbits per output character (1 to %d)\n"
"\t-i INIT\t\tinitial register value\n"
"\t-k KPOLY\tgenerator in Koopman notation (implies WIDTH)\n"
"\t-m MODEL\tpreset CRC algorithm\n"
"\t-p POLY\t\tgenerator or search range start polynomial\n"
"\t-P RPOLY\treversed generator polynomial (implies WIDTH)\n",
BMP_BIT, BMP_BIT);
fprintf(stderr,
"\t-q QPOLY\tsearch range end polynomial\n"
"\t-w WIDTH\tregister size, in bits\n"
"\t-x XOROUT\tfinal register XOR value\n"
"Modifier switches:\n"
"\t-b big-endian CRC\t\t-B big-endian CRC output\n"
"\t-f read files named in STRINGs\t-F skip preset model check pass\n"
"\t-G skip brute force search pass\t-l little-endian CRC\n"
"\t-L little-endian CRC output\t-M non-augmenting algorithm\n"
"\t-r right-justified output\t-S print spaces between characters\n"
"\t-t left-justified output\t-V reverse algorithm only\n"
"\t-X print uppercase hexadecimal\t-y low bytes first in files\n"
"\t-z raw binary STRINGs\n");
fprintf(stderr,
"Mode switches:\n"
"\t-c calculate CRCs\t\t-d dump algorithm parameters\n"
"\t-D list preset algorithms\t-e echo (and reformat) input\n"
"\t-s search for algorithm\t\t-v calculate reversed CRCs\n"
"\t-g search for alg given hex+crc\n"
"\t-h | -u | -? show this help\n"
"Common Use Examples:\n"
"\t reveng -g 01020304e3\n"
"\t Searches for a known/common crc preset that computes the crc\n"
"\t on the end of the given hex string\n"
"\t reveng -w 8 -s 01020304e3 010204039d\n"
"\t Searches for any possible 8 bit width crc calc that computes\n"
"\t the crc on the end of the given hex string(s)\n"
"\t reveng -m CRC-8 -c 01020304\n"
"\t Calculates the crc-8 of the given hex string\n"
"\t reveng -D\n"
"\t Outputs a list of all known/common crc models with their\n"
"\t preset values\n"
"\n"
"Copyright (C)\n"
"2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Gregory Cook\n"
"This is free software; see the source for copying conditions. There is NO\n"
"warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
"Version "
VERSION
"\t\t\t\t <http://reveng.sourceforge.net/>\n");
}