/* 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 . */ /* 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 #include #include "cliparser/getopt.h" #ifdef _WIN32 # include # include # 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 = PZERO; 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 \n"); }