/* $OpenBSD: file.c,v 1.13 2003/07/02 21:04:09 deraadt Exp $ */ /* * file - find type of a file or files - main program. * * Copyright (c) Ian F. Darwin 1986-1995. * Software written by Ian F. Darwin and others; * maintained 1995-present by Christos Zoulas and others. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice immediately at the beginning of the file, without modification, * this list of conditions, and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef lint static char *moduleid = "$OpenBSD: file.c,v 1.13 2003/07/02 21:04:09 deraadt Exp $"; #endif /* lint */ #include #include #include #include #include /* for MAXPATHLEN */ #include #include /* for open() */ #if (__COHERENT__ >= 0x420) # include #else # ifdef USE_UTIMES # include # else # include # endif #endif #include /* for read() */ #include #include /* for byte swapping */ #include "patchlevel.h" #include "file.h" #ifdef S_IFLNK # define USAGE "Usage: %s [-vbczL] [-f namefile] [-m magicfiles] file...\n" #else # define USAGE "Usage: %s [-vbcz] [-f namefile] [-m magicfiles] file...\n" #endif #ifndef MAGIC # define MAGIC "/etc/magic" #endif int /* Global command-line options */ debug = 0, /* debugging */ bflag = 0, /* Don't print filename */ lflag = 0, /* follow Symlinks (BSD only) */ zflag = 0; /* follow (uncompress) compressed files */ int /* Misc globals */ nmagic = 0; /* number of valid magic[]s */ struct magic *magic; /* array of magic entries */ char *magicfile; /* where magic be found */ int lineno; /* line number in the magic file */ static void unwrap(char *fn); #if 0 static int byteconv4(int, int, int); static short byteconv2(int, int, int); #endif /* * main - parse arguments and handle options */ int main(int argc, char *argv[]) { int c; int check = 0, didsomefiles = 0, errflg = 0, ret = 0, app = 0; extern char *__progname; if (!(magicfile = getenv("MAGIC"))) magicfile = MAGIC; while ((c = getopt(argc, argv, "bvcdf:Lm:z")) != -1) switch (c) { case 'v': (void) printf("%s-%d.%d\n", __progname, FILE_VERSION_MAJOR, patchlevel); return 1; case 'b': ++bflag; break; case 'c': ++check; break; case 'd': ++debug; break; case 'f': if (!app) { ret = apprentice(magicfile, check); if (check) exit(ret); app = 1; } unwrap(optarg); ++didsomefiles; break; #ifdef S_IFLNK case 'L': ++lflag; break; #endif case 'm': magicfile = optarg; break; case 'z': zflag++; break; case '?': default: errflg++; break; } if (errflg) { (void) fprintf(stderr, USAGE, __progname); exit(2); } if (!app) { ret = apprentice(magicfile, check); if (check) exit(ret); app = 1; } if (optind == argc) { if (!didsomefiles) { fprintf(stderr, USAGE, __progname); exit(2); } } else { int i, wid, nw; for (wid = 0, i = optind; i < argc; i++) { nw = strlen(argv[i]); if (nw > wid) wid = nw; } for (; optind < argc; optind++) process(argv[optind], wid); } return 0; } /* * unwrap -- read a file of filenames, do each one. */ static void unwrap(fn) char *fn; { char buf[MAXPATHLEN]; FILE *f; int wid = 0, cwid; if (strcmp("-", fn) == 0) { f = stdin; wid = 1; } else { if ((f = fopen(fn, "r")) == NULL) { err(1, "Cannot open `%s'", fn); /*NOTREACHED*/ } while (fgets(buf, sizeof(buf), f) != NULL) { cwid = strlen(buf) - 1; if (cwid > wid) wid = cwid; } rewind(f); } while (fgets(buf, sizeof(buf), f) != NULL) { buf[strlen(buf)-1] = '\0'; process(buf, wid); } (void) fclose(f); } #if 0 /* * byteconv4 * Input: * from 4 byte quantity to convert * same whether to perform byte swapping * big_endian whether we are a big endian host */ static int byteconv4(from, same, big_endian) int from; int same; int big_endian; { if (same) return from; else if (big_endian) /* lsb -> msb conversion on msb */ { union { int i; char c[4]; } retval, tmpval; tmpval.i = from; retval.c[0] = tmpval.c[3]; retval.c[1] = tmpval.c[2]; retval.c[2] = tmpval.c[1]; retval.c[3] = tmpval.c[0]; return retval.i; } else return ntohl(from); /* msb -> lsb conversion on lsb */ } /* * byteconv2 * Same as byteconv4, but for shorts */ static short byteconv2(from, same, big_endian) int from; int same; int big_endian; { if (same) return from; else if (big_endian) /* lsb -> msb conversion on msb */ { union { short s; char c[2]; } retval, tmpval; tmpval.s = (short) from; retval.c[0] = tmpval.c[1]; retval.c[1] = tmpval.c[0]; return retval.s; } else return ntohs(from); /* msb -> lsb conversion on lsb */ } #endif /* * process - process input file */ void process(inname, wid) const char *inname; int wid; { int fd = 0; static const char stdname[] = "standard input"; unsigned char buf[HOWMANY+1]; /* one extra for terminating '\0' */ struct stat sb; int nbytes = 0; /* number of bytes read from a datafile */ char match = '\0'; if (strcmp("-", inname) == 0) { if (fstat(0, &sb)<0) { err(1, "cannot fstat `%s'", stdname); /*NOTREACHED*/ } inname = stdname; } if (wid > 0 && !bflag) (void) printf("%s:%*s ", inname, (int) (wid - strlen(inname)), ""); if (inname != stdname) { /* * first try judging the file based on its filesystem status */ if (fsmagic(inname, &sb) != 0) { putchar('\n'); return; } if ((fd = open(inname, O_RDONLY)) < 0) { /* We can't open it, but we were able to stat it. */ if (sb.st_mode & 0002) ckfputs("writable, ", stdout); if (sb.st_mode & 0111) ckfputs("executable, ", stdout); ckfprintf(stdout, "can't read `%s' (%s).\n", inname, strerror(errno)); return; } } /* * try looking at the first HOWMANY bytes */ if ((nbytes = read(fd, (char *)buf, HOWMANY)) == -1) { err(1, "read failed"); /*NOTREACHED*/ } if (nbytes == 0) ckfputs("empty", stdout); else { buf[nbytes++] = '\0'; /* null-terminate it */ match = tryit(buf, nbytes, zflag); } #ifdef BUILTIN_ELF if (match == 's' && nbytes > 5) tryelf(fd, buf, nbytes); #endif if (inname != stdname) { #ifdef RESTORE_TIME /* * Try to restore access, modification times if read it. */ # ifdef USE_UTIMES struct timeval utsbuf[2]; utsbuf[0].tv_sec = sb.st_atime; utsbuf[1].tv_sec = sb.st_mtime; (void) utimes(inname, utsbuf); /* don't care if loses */ # else struct utimbuf utbuf; utbuf.actime = sb.st_atime; utbuf.modtime = sb.st_mtime; (void) utime(inname, &utbuf); /* don't care if loses */ # endif #endif (void) close(fd); } (void) putchar('\n'); } int tryit(buf, nb, zflag) unsigned char *buf; int nb, zflag; { /* try compression stuff */ if (zflag && zmagic(buf, nb)) return 'z'; /* try tests in /etc/magic (or surrogate magic file) */ if (softmagic(buf, nb)) return 's'; /* try known keywords, check whether it is ASCII */ if (ascmagic(buf, nb)) return 'a'; /* see if it's international language text */ if (internatmagic(buf, nb)) return 'i'; /* abandon hope, all ye who remain here */ ckfputs("data", stdout); return '\0'; }