/* * 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. */ /* * apprentice - make one pass through /etc/magic, learning its secrets. */ #include "file.h" #ifndef lint FILE_RCSID("@(#)$File: apprentice.c,v 1.170 2011/06/10 09:23:28 christos Exp $") #endif /* lint */ #include "magic.h" #include #ifdef HAVE_UNISTD_H #include #endif #include #include #include #include #ifdef QUICK #include #endif #include #define EATAB {while (isascii((unsigned char) *l) && \ isspace((unsigned char) *l)) ++l;} #define LOWCASE(l) (isupper((unsigned char) (l)) ? \ tolower((unsigned char) (l)) : (l)) /* * Work around a bug in headers on Digital Unix. * At least confirmed for: OSF1 V4.0 878 */ #if defined(__osf__) && defined(__DECC) #ifdef MAP_FAILED #undef MAP_FAILED #endif #endif #ifndef MAP_FAILED #define MAP_FAILED (void *) -1 #endif #ifndef MAP_FILE #define MAP_FILE 0 #endif struct magic_entry { struct magic *mp; uint32_t cont_count; uint32_t max_count; }; int file_formats[FILE_NAMES_SIZE]; const size_t file_nformats = FILE_NAMES_SIZE; const char *file_names[FILE_NAMES_SIZE]; const size_t file_nnames = FILE_NAMES_SIZE; private int getvalue(struct magic_set *ms, struct magic *, const char **, int); private int hextoint(int); private const char *getstr(struct magic_set *, struct magic *, const char *, int); private int parse(struct magic_set *, struct magic_entry **, uint32_t *, const char *, size_t, int); private void eatsize(const char **); private int apprentice_1(struct magic_set *, const char *, int, struct mlist *); private size_t apprentice_magic_strength(const struct magic *); private int apprentice_sort(const void *, const void *); private void apprentice_list(struct mlist *, int ); private int apprentice_load(struct magic_set *, struct magic **, uint32_t *, const char *, int); private void byteswap(struct magic *, uint32_t); private void bs1(struct magic *); private uint16_t swap2(uint16_t); private uint32_t swap4(uint32_t); private uint64_t swap8(uint64_t); private char *mkdbname(struct magic_set *, const char *, int); private int apprentice_map(struct magic_set *, struct magic **, uint32_t *, const char *); private int apprentice_compile(struct magic_set *, struct magic **, uint32_t *, const char *); private int check_format_type(const char *, int); private int check_format(struct magic_set *, struct magic *); private int get_op(char); private int parse_mime(struct magic_set *, struct magic_entry *, const char *); private int parse_strength(struct magic_set *, struct magic_entry *, const char *); private int parse_apple(struct magic_set *, struct magic_entry *, const char *); private size_t maxmagic = 0; private size_t magicsize = sizeof(struct magic); private const char usg_hdr[] = "cont\toffset\ttype\topcode\tmask\tvalue\tdesc"; private struct { const char *name; size_t len; int (*fun)(struct magic_set *, struct magic_entry *, const char *); } bang[] = { #define DECLARE_FIELD(name) { # name, sizeof(# name) - 1, parse_ ## name } DECLARE_FIELD(mime), DECLARE_FIELD(apple), DECLARE_FIELD(strength), #undef DECLARE_FIELD { NULL, 0, NULL } }; #ifdef COMPILE_ONLY int main(int, char *[]); int main(int argc, char *argv[]) { int ret; struct magic_set *ms; char *progname; if ((progname = strrchr(argv[0], '/')) != NULL) progname++; else progname = argv[0]; if (argc != 2) { (void)fprintf(stderr, "Usage: %s file\n", progname); return 1; } if ((ms = magic_open(MAGIC_CHECK)) == NULL) { (void)fprintf(stderr, "%s: %s\n", progname, strerror(errno)); return 1; } ret = magic_compile(ms, argv[1]) == -1 ? 1 : 0; if (ret == 1) (void)fprintf(stderr, "%s: %s\n", progname, magic_error(ms)); magic_close(ms); return ret; } #endif /* COMPILE_ONLY */ static const struct type_tbl_s { const char name[16]; const size_t len; const int type; const int format; } type_tbl[] = { # define XX(s) s, (sizeof(s) - 1) # define XX_NULL "", 0 { XX("byte"), FILE_BYTE, FILE_FMT_NUM }, { XX("short"), FILE_SHORT, FILE_FMT_NUM }, { XX("default"), FILE_DEFAULT, FILE_FMT_STR }, { XX("long"), FILE_LONG, FILE_FMT_NUM }, { XX("string"), FILE_STRING, FILE_FMT_STR }, { XX("date"), FILE_DATE, FILE_FMT_STR }, { XX("beshort"), FILE_BESHORT, FILE_FMT_NUM }, { XX("belong"), FILE_BELONG, FILE_FMT_NUM }, { XX("bedate"), FILE_BEDATE, FILE_FMT_STR }, { XX("leshort"), FILE_LESHORT, FILE_FMT_NUM }, { XX("lelong"), FILE_LELONG, FILE_FMT_NUM }, { XX("ledate"), FILE_LEDATE, FILE_FMT_STR }, { XX("pstring"), FILE_PSTRING, FILE_FMT_STR }, { XX("ldate"), FILE_LDATE, FILE_FMT_STR }, { XX("beldate"), FILE_BELDATE, FILE_FMT_STR }, { XX("leldate"), FILE_LELDATE, FILE_FMT_STR }, { XX("regex"), FILE_REGEX, FILE_FMT_STR }, { XX("bestring16"), FILE_BESTRING16, FILE_FMT_STR }, { XX("lestring16"), FILE_LESTRING16, FILE_FMT_STR }, { XX("search"), FILE_SEARCH, FILE_FMT_STR }, { XX("medate"), FILE_MEDATE, FILE_FMT_STR }, { XX("meldate"), FILE_MELDATE, FILE_FMT_STR }, { XX("melong"), FILE_MELONG, FILE_FMT_NUM }, { XX("quad"), FILE_QUAD, FILE_FMT_QUAD }, { XX("lequad"), FILE_LEQUAD, FILE_FMT_QUAD }, { XX("bequad"), FILE_BEQUAD, FILE_FMT_QUAD }, { XX("qdate"), FILE_QDATE, FILE_FMT_STR }, { XX("leqdate"), FILE_LEQDATE, FILE_FMT_STR }, { XX("beqdate"), FILE_BEQDATE, FILE_FMT_STR }, { XX("qldate"), FILE_QLDATE, FILE_FMT_STR }, { XX("leqldate"), FILE_LEQLDATE, FILE_FMT_STR }, { XX("beqldate"), FILE_BEQLDATE, FILE_FMT_STR }, { XX("float"), FILE_FLOAT, FILE_FMT_FLOAT }, { XX("befloat"), FILE_BEFLOAT, FILE_FMT_FLOAT }, { XX("lefloat"), FILE_LEFLOAT, FILE_FMT_FLOAT }, { XX("double"), FILE_DOUBLE, FILE_FMT_DOUBLE }, { XX("bedouble"), FILE_BEDOUBLE, FILE_FMT_DOUBLE }, { XX("ledouble"), FILE_LEDOUBLE, FILE_FMT_DOUBLE }, { XX("leid3"), FILE_LEID3, FILE_FMT_NUM }, { XX("beid3"), FILE_BEID3, FILE_FMT_NUM }, { XX("indirect"), FILE_INDIRECT, FILE_FMT_NONE }, { XX_NULL, FILE_INVALID, FILE_FMT_NONE }, # undef XX # undef XX_NULL }; private int get_type(const char *l, const char **t) { const struct type_tbl_s *p; for (p = type_tbl; p->len; p++) { if (strncmp(l, p->name, p->len) == 0) { if (t) *t = l + p->len; break; } } return p->type; } private void init_file_tables(void) { static int done = 0; const struct type_tbl_s *p; if (done) return; done++; for (p = type_tbl; p->len; p++) { assert(p->type < FILE_NAMES_SIZE); file_names[p->type] = p->name; file_formats[p->type] = p->format; } } /* * Handle one file or directory. */ private int apprentice_1(struct magic_set *ms, const char *fn, int action, struct mlist *mlist) { struct magic *magic = NULL; uint32_t nmagic = 0; struct mlist *ml; int rv = -1; int mapped; if (magicsize != FILE_MAGICSIZE) { file_error(ms, 0, "magic element size %lu != %lu", (unsigned long)sizeof(*magic), (unsigned long)FILE_MAGICSIZE); return -1; } if (action == FILE_COMPILE) { rv = apprentice_load(ms, &magic, &nmagic, fn, action); if (rv != 0) return -1; rv = apprentice_compile(ms, &magic, &nmagic, fn); free(magic); return rv; } #ifndef COMPILE_ONLY if ((rv = apprentice_map(ms, &magic, &nmagic, fn)) == -1) { if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "using regular magic file `%s'", fn); rv = apprentice_load(ms, &magic, &nmagic, fn, action); if (rv != 0) return -1; } mapped = rv; if (magic == NULL) { file_delmagic(magic, mapped, nmagic); return -1; } if ((ml = CAST(struct mlist *, malloc(sizeof(*ml)))) == NULL) { file_delmagic(magic, mapped, nmagic); file_oomem(ms, sizeof(*ml)); return -1; } ml->magic = magic; ml->nmagic = nmagic; ml->mapped = mapped; mlist->prev->next = ml; ml->prev = mlist->prev; ml->next = mlist; mlist->prev = ml; if (action == FILE_LIST) { printf("Binary patterns:\n"); apprentice_list(mlist, BINTEST); printf("Text patterns:\n"); apprentice_list(mlist, TEXTTEST); } return 0; #endif /* COMPILE_ONLY */ } protected void file_delmagic(struct magic *p, int type, size_t entries) { if (p == NULL) return; switch (type) { case 2: #ifdef QUICK p--; (void)munmap((void *)p, sizeof(*p) * (entries + 1)); break; #else (void)&entries; abort(); /*NOTREACHED*/ #endif case 1: p--; /*FALLTHROUGH*/ case 0: free(p); break; default: abort(); } } /* const char *fn: list of magic files and directories */ protected struct mlist * file_apprentice(struct magic_set *ms, const char *fn, int action) { char *p, *mfn; int file_err, errs = -1; struct mlist *mlist; if ((fn = magic_getpath(fn, action)) == NULL) return NULL; init_file_tables(); if ((mfn = strdup(fn)) == NULL) { file_oomem(ms, strlen(fn)); return NULL; } fn = mfn; if ((mlist = CAST(struct mlist *, malloc(sizeof(*mlist)))) == NULL) { free(mfn); file_oomem(ms, sizeof(*mlist)); return NULL; } mlist->next = mlist->prev = mlist; while (fn) { p = strchr(fn, PATHSEP); if (p) *p++ = '\0'; if (*fn == '\0') break; file_err = apprentice_1(ms, fn, action, mlist); errs = MAX(errs, file_err); fn = p; } if (errs == -1) { free(mfn); free(mlist); mlist = NULL; file_error(ms, 0, "could not find any magic files!"); return NULL; } free(mfn); return mlist; } /* * Get weight of this magic entry, for sorting purposes. */ private size_t apprentice_magic_strength(const struct magic *m) { #define MULT 10 size_t val = 2 * MULT; /* baseline strength */ switch (m->type) { case FILE_DEFAULT: /* make sure this sorts last */ if (m->factor_op != FILE_FACTOR_OP_NONE) abort(); return 0; case FILE_BYTE: val += 1 * MULT; break; case FILE_SHORT: case FILE_LESHORT: case FILE_BESHORT: val += 2 * MULT; break; case FILE_LONG: case FILE_LELONG: case FILE_BELONG: case FILE_MELONG: val += 4 * MULT; break; case FILE_PSTRING: case FILE_STRING: val += m->vallen * MULT; break; case FILE_BESTRING16: case FILE_LESTRING16: val += m->vallen * MULT / 2; break; case FILE_SEARCH: case FILE_REGEX: val += m->vallen * MAX(MULT / m->vallen, 1); break; case FILE_DATE: case FILE_LEDATE: case FILE_BEDATE: case FILE_MEDATE: case FILE_LDATE: case FILE_LELDATE: case FILE_BELDATE: case FILE_MELDATE: case FILE_FLOAT: case FILE_BEFLOAT: case FILE_LEFLOAT: val += 4 * MULT; break; case FILE_QUAD: case FILE_BEQUAD: case FILE_LEQUAD: case FILE_QDATE: case FILE_LEQDATE: case FILE_BEQDATE: case FILE_QLDATE: case FILE_LEQLDATE: case FILE_BEQLDATE: case FILE_DOUBLE: case FILE_BEDOUBLE: case FILE_LEDOUBLE: val += 8 * MULT; break; default: val = 0; (void)fprintf(stderr, "Bad type %d\n", m->type); abort(); } switch (m->reln) { case 'x': /* matches anything penalize */ case '!': /* matches almost anything penalize */ val = 0; break; case '=': /* Exact match, prefer */ val += MULT; break; case '>': case '<': /* comparison match reduce strength */ val -= 2 * MULT; break; case '^': case '&': /* masking bits, we could count them too */ val -= MULT; break; default: (void)fprintf(stderr, "Bad relation %c\n", m->reln); abort(); } if (val == 0) /* ensure we only return 0 for FILE_DEFAULT */ val = 1; switch (m->factor_op) { case FILE_FACTOR_OP_NONE: break; case FILE_FACTOR_OP_PLUS: val += m->factor; break; case FILE_FACTOR_OP_MINUS: val -= m->factor; break; case FILE_FACTOR_OP_TIMES: val *= m->factor; break; case FILE_FACTOR_OP_DIV: val /= m->factor; break; default: abort(); } /* * Magic entries with no description get a bonus because they depend * on subsequent magic entries to print something. */ if (m->desc[0] == '\0') val++; return val; } /* * Sort callback for sorting entries by "strength" (basically length) */ private int apprentice_sort(const void *a, const void *b) { const struct magic_entry *ma = CAST(const struct magic_entry *, a); const struct magic_entry *mb = CAST(const struct magic_entry *, b); size_t sa = apprentice_magic_strength(ma->mp); size_t sb = apprentice_magic_strength(mb->mp); if (sa == sb) return 0; else if (sa > sb) return -1; else return 1; } /* * Shows sorted patterns list in the order which is used for the matching */ private void apprentice_list(struct mlist *mlist, int mode) { uint32_t magindex = 0; struct mlist *ml; for (ml = mlist->next; ml != mlist; ml = ml->next) { for (magindex = 0; magindex < ml->nmagic; magindex++) { struct magic *m = &ml->magic[magindex]; if ((m->flag & mode) != mode) { /* Skip sub-tests */ while (magindex + 1 < ml->nmagic && ml->magic[magindex + 1].cont_level != 0) ++magindex; continue; /* Skip to next top-level test*/ } /* * Try to iterate over the tree until we find item with * description/mimetype. */ while (magindex + 1 < ml->nmagic && ml->magic[magindex + 1].cont_level != 0 && *ml->magic[magindex].desc == '\0' && *ml->magic[magindex].mimetype == '\0') magindex++; printf("Strength = %3" SIZE_T_FORMAT "u : %s [%s]\n", apprentice_magic_strength(m), ml->magic[magindex].desc, ml->magic[magindex].mimetype); } } } private void set_test_type(struct magic *mstart, struct magic *m) { switch (m->type) { case FILE_BYTE: case FILE_SHORT: case FILE_LONG: case FILE_DATE: case FILE_BESHORT: case FILE_BELONG: case FILE_BEDATE: case FILE_LESHORT: case FILE_LELONG: case FILE_LEDATE: case FILE_LDATE: case FILE_BELDATE: case FILE_LELDATE: case FILE_MEDATE: case FILE_MELDATE: case FILE_MELONG: case FILE_QUAD: case FILE_LEQUAD: case FILE_BEQUAD: case FILE_QDATE: case FILE_LEQDATE: case FILE_BEQDATE: case FILE_QLDATE: case FILE_LEQLDATE: case FILE_BEQLDATE: case FILE_FLOAT: case FILE_BEFLOAT: case FILE_LEFLOAT: case FILE_DOUBLE: case FILE_BEDOUBLE: case FILE_LEDOUBLE: mstart->flag |= BINTEST; break; case FILE_STRING: case FILE_PSTRING: case FILE_BESTRING16: case FILE_LESTRING16: /* Allow text overrides */ if (mstart->str_flags & STRING_TEXTTEST) mstart->flag |= TEXTTEST; else mstart->flag |= BINTEST; break; case FILE_REGEX: case FILE_SEARCH: /* Check for override */ if (mstart->str_flags & STRING_BINTEST) mstart->flag |= BINTEST; if (mstart->str_flags & STRING_TEXTTEST) mstart->flag |= TEXTTEST; if (mstart->flag & (TEXTTEST|BINTEST)) break; /* binary test if pattern is not text */ if (file_looks_utf8(m->value.us, (size_t)m->vallen, NULL, NULL) <= 0) mstart->flag |= BINTEST; else mstart->flag |= TEXTTEST; break; case FILE_DEFAULT: /* can't deduce anything; we shouldn't see this at the top level anyway */ break; case FILE_INVALID: default: /* invalid search type, but no need to complain here */ break; } } /* * Load and parse one file. */ private void load_1(struct magic_set *ms, int action, const char *fn, int *errs, struct magic_entry **marray, uint32_t *marraycount) { size_t lineno = 0, llen = 0; char *line = NULL; ssize_t len; FILE *f = fopen(ms->file = fn, "r"); if (f == NULL) { if (errno != ENOENT) file_error(ms, errno, "cannot read magic file `%s'", fn); (*errs)++; return; } /* read and parse this file */ for (ms->line = 1; (len = getline(&line, &llen, f)) != -1; ms->line++) { if (len == 0) /* null line, garbage, etc */ continue; if (line[len - 1] == '\n') { lineno++; line[len - 1] = '\0'; /* delete newline */ } switch (line[0]) { case '\0': /* empty, do not parse */ case '#': /* comment, do not parse */ continue; case '!': if (line[1] == ':') { size_t i; for (i = 0; bang[i].name != NULL; i++) { if ((size_t)(len - 2) > bang[i].len && memcmp(bang[i].name, line + 2, bang[i].len) == 0) break; } if (bang[i].name == NULL) { file_error(ms, 0, "Unknown !: entry `%s'", line); (*errs)++; continue; } if (*marraycount == 0) { file_error(ms, 0, "No current entry for :!%s type", bang[i].name); (*errs)++; continue; } if ((*bang[i].fun)(ms, &(*marray)[*marraycount - 1], line + bang[i].len + 2) != 0) { (*errs)++; continue; } continue; } /*FALLTHROUGH*/ default: if (parse(ms, marray, marraycount, line, lineno, action) != 0) (*errs)++; break; } } if (line) free(line); (void)fclose(f); } /* * parse a file or directory of files * const char *fn: name of magic file or directory */ private int cmpstrp(const void *p1, const void *p2) { return strcmp(*(char *const *)p1, *(char *const *)p2); } private int apprentice_load(struct magic_set *ms, struct magic **magicp, uint32_t *nmagicp, const char *fn, int action) { int errs = 0; struct magic_entry *marray; uint32_t marraycount, i, mentrycount = 0, starttest; size_t slen, files = 0, maxfiles = 0; char **filearr = NULL, *mfn; struct stat st; DIR *dir; struct dirent *d; ms->flags |= MAGIC_CHECK; /* Enable checks for parsed files */ maxmagic = MAXMAGIS; if ((marray = CAST(struct magic_entry *, calloc(maxmagic, sizeof(*marray)))) == NULL) { file_oomem(ms, maxmagic * sizeof(*marray)); return -1; } marraycount = 0; /* print silly verbose header for USG compat. */ if (action == FILE_CHECK) (void)fprintf(stderr, "%s\n", usg_hdr); /* load directory or file */ if (stat(fn, &st) == 0 && S_ISDIR(st.st_mode)) { dir = opendir(fn); if (!dir) { errs++; goto out; } while ((d = readdir(dir)) != NULL) { if (asprintf(&mfn, "%s/%s", fn, d->d_name) < 0) { file_oomem(ms, strlen(fn) + strlen(d->d_name) + 2); errs++; goto out; } if (stat(mfn, &st) == -1 || !S_ISREG(st.st_mode)) { free(mfn); continue; } if (files >= maxfiles) { size_t mlen; maxfiles = (maxfiles + 1) * 2; mlen = maxfiles * sizeof(*filearr); if ((filearr = CAST(char **, realloc(filearr, mlen))) == NULL) { file_oomem(ms, mlen); free(mfn); errs++; goto out; } } filearr[files++] = mfn; } closedir(dir); qsort(filearr, files, sizeof(*filearr), cmpstrp); for (i = 0; i < files; i++) { load_1(ms, action, filearr[i], &errs, &marray, &marraycount); free(filearr[i]); } free(filearr); } else load_1(ms, action, fn, &errs, &marray, &marraycount); if (errs) goto out; /* Set types of tests */ for (i = 0; i < marraycount; ) { if (marray[i].mp->cont_level != 0) { i++; continue; } starttest = i; do { static const char text[] = "text"; static const char binary[] = "binary"; static const size_t len = sizeof(text); set_test_type(marray[starttest].mp, marray[i].mp); if ((ms->flags & MAGIC_DEBUG) == 0) continue; (void)fprintf(stderr, "%s%s%s: %s\n", marray[i].mp->mimetype, marray[i].mp->mimetype[0] == '\0' ? "" : "; ", marray[i].mp->desc[0] ? marray[i].mp->desc : "(no description)", marray[i].mp->flag & BINTEST ? binary : text); if (marray[i].mp->flag & BINTEST) { char *p = strstr(marray[i].mp->desc, text); if (p && (p == marray[i].mp->desc || isspace((unsigned char)p[-1])) && (p + len - marray[i].mp->desc == MAXstring || (p[len] == '\0' || isspace((unsigned char)p[len])))) (void)fprintf(stderr, "*** Possible " "binary test for text type\n"); } } while (++i < marraycount && marray[i].mp->cont_level != 0); } qsort(marray, marraycount, sizeof(*marray), apprentice_sort); /* * Make sure that any level 0 "default" line is last (if one exists). */ for (i = 0; i < marraycount; i++) { if (marray[i].mp->cont_level == 0 && marray[i].mp->type == FILE_DEFAULT) { while (++i < marraycount) if (marray[i].mp->cont_level == 0) break; if (i != marraycount) { /* XXX - Ugh! */ ms->line = marray[i].mp->lineno; file_magwarn(ms, "level 0 \"default\" did not sort last"); } break; } } for (i = 0; i < marraycount; i++) mentrycount += marray[i].cont_count; slen = sizeof(**magicp) * mentrycount; if ((*magicp = CAST(struct magic *, malloc(slen))) == NULL) { file_oomem(ms, slen); errs++; goto out; } mentrycount = 0; for (i = 0; i < marraycount; i++) { (void)memcpy(*magicp + mentrycount, marray[i].mp, marray[i].cont_count * sizeof(**magicp)); mentrycount += marray[i].cont_count; } out: for (i = 0; i < marraycount; i++) free(marray[i].mp); free(marray); if (errs) { *magicp = NULL; *nmagicp = 0; return errs; } else { *nmagicp = mentrycount; return 0; } } /* * extend the sign bit if the comparison is to be signed */ protected uint64_t file_signextend(struct magic_set *ms, struct magic *m, uint64_t v) { if (!(m->flag & UNSIGNED)) { switch(m->type) { /* * Do not remove the casts below. They are * vital. When later compared with the data, * the sign extension must have happened. */ case FILE_BYTE: v = (char) v; break; case FILE_SHORT: case FILE_BESHORT: case FILE_LESHORT: v = (short) v; break; case FILE_DATE: case FILE_BEDATE: case FILE_LEDATE: case FILE_MEDATE: case FILE_LDATE: case FILE_BELDATE: case FILE_LELDATE: case FILE_MELDATE: case FILE_LONG: case FILE_BELONG: case FILE_LELONG: case FILE_MELONG: case FILE_FLOAT: case FILE_BEFLOAT: case FILE_LEFLOAT: v = (int32_t) v; break; case FILE_QUAD: case FILE_BEQUAD: case FILE_LEQUAD: case FILE_QDATE: case FILE_QLDATE: case FILE_BEQDATE: case FILE_BEQLDATE: case FILE_LEQDATE: case FILE_LEQLDATE: case FILE_DOUBLE: case FILE_BEDOUBLE: case FILE_LEDOUBLE: v = (int64_t) v; break; case FILE_STRING: case FILE_PSTRING: case FILE_BESTRING16: case FILE_LESTRING16: case FILE_REGEX: case FILE_SEARCH: case FILE_DEFAULT: case FILE_INDIRECT: break; default: if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "cannot happen: m->type=%d\n", m->type); return ~0U; } } return v; } private int string_modifier_check(struct magic_set *ms, struct magic *m) { if ((ms->flags & MAGIC_CHECK) == 0) return 0; if (m->type != FILE_PSTRING && (m->str_flags & PSTRING_LEN) != 0) { file_magwarn(ms, "'/BHhLl' modifiers are only allowed for pascal strings\n"); return -1; } switch (m->type) { case FILE_BESTRING16: case FILE_LESTRING16: if (m->str_flags != 0) { file_magwarn(ms, "no modifiers allowed for 16-bit strings\n"); return -1; } break; case FILE_STRING: case FILE_PSTRING: if ((m->str_flags & REGEX_OFFSET_START) != 0) { file_magwarn(ms, "'/%c' only allowed on regex and search\n", CHAR_REGEX_OFFSET_START); return -1; } break; case FILE_SEARCH: if (m->str_range == 0) { file_magwarn(ms, "missing range; defaulting to %d\n", STRING_DEFAULT_RANGE); m->str_range = STRING_DEFAULT_RANGE; return -1; } break; case FILE_REGEX: if ((m->str_flags & STRING_COMPACT_WHITESPACE) != 0) { file_magwarn(ms, "'/%c' not allowed on regex\n", CHAR_COMPACT_WHITESPACE); return -1; } if ((m->str_flags & STRING_COMPACT_OPTIONAL_WHITESPACE) != 0) { file_magwarn(ms, "'/%c' not allowed on regex\n", CHAR_COMPACT_OPTIONAL_WHITESPACE); return -1; } break; default: file_magwarn(ms, "coding error: m->type=%d\n", m->type); return -1; } return 0; } private int get_op(char c) { switch (c) { case '&': return FILE_OPAND; case '|': return FILE_OPOR; case '^': return FILE_OPXOR; case '+': return FILE_OPADD; case '-': return FILE_OPMINUS; case '*': return FILE_OPMULTIPLY; case '/': return FILE_OPDIVIDE; case '%': return FILE_OPMODULO; default: return -1; } } #ifdef ENABLE_CONDITIONALS private int get_cond(const char *l, const char **t) { static const struct cond_tbl_s { char name[8]; size_t len; int cond; } cond_tbl[] = { { "if", 2, COND_IF }, { "elif", 4, COND_ELIF }, { "else", 4, COND_ELSE }, { "", 0, COND_NONE }, }; const struct cond_tbl_s *p; for (p = cond_tbl; p->len; p++) { if (strncmp(l, p->name, p->len) == 0 && isspace((unsigned char)l[p->len])) { if (t) *t = l + p->len; break; } } return p->cond; } private int check_cond(struct magic_set *ms, int cond, uint32_t cont_level) { int last_cond; last_cond = ms->c.li[cont_level].last_cond; switch (cond) { case COND_IF: if (last_cond != COND_NONE && last_cond != COND_ELIF) { if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "syntax error: `if'"); return -1; } last_cond = COND_IF; break; case COND_ELIF: if (last_cond != COND_IF && last_cond != COND_ELIF) { if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "syntax error: `elif'"); return -1; } last_cond = COND_ELIF; break; case COND_ELSE: if (last_cond != COND_IF && last_cond != COND_ELIF) { if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "syntax error: `else'"); return -1; } last_cond = COND_NONE; break; case COND_NONE: last_cond = COND_NONE; break; } ms->c.li[cont_level].last_cond = last_cond; return 0; } #endif /* ENABLE_CONDITIONALS */ /* * parse one line from magic file, put into magic[index++] if valid */ private int parse(struct magic_set *ms, struct magic_entry **mentryp, uint32_t *nmentryp, const char *line, size_t lineno, int action) { #ifdef ENABLE_CONDITIONALS static uint32_t last_cont_level = 0; #endif size_t i; struct magic_entry *me; struct magic *m; const char *l = line; char *t; int op; uint32_t cont_level; cont_level = 0; while (*l == '>') { ++l; /* step over */ cont_level++; } #ifdef ENABLE_CONDITIONALS if (cont_level == 0 || cont_level > last_cont_level) if (file_check_mem(ms, cont_level) == -1) return -1; last_cont_level = cont_level; #endif #define ALLOC_CHUNK (size_t)10 #define ALLOC_INCR (size_t)200 if (cont_level != 0) { if (*nmentryp == 0) { file_error(ms, 0, "No current entry for continuation"); return -1; } me = &(*mentryp)[*nmentryp - 1]; if (me->cont_count == me->max_count) { struct magic *nm; size_t cnt = me->max_count + ALLOC_CHUNK; if ((nm = CAST(struct magic *, realloc(me->mp, sizeof(*nm) * cnt))) == NULL) { file_oomem(ms, sizeof(*nm) * cnt); return -1; } me->mp = m = nm; me->max_count = CAST(uint32_t, cnt); } m = &me->mp[me->cont_count++]; (void)memset(m, 0, sizeof(*m)); m->cont_level = cont_level; } else { if (*nmentryp == maxmagic) { struct magic_entry *mp; maxmagic += ALLOC_INCR; if ((mp = CAST(struct magic_entry *, realloc(*mentryp, sizeof(*mp) * maxmagic))) == NULL) { file_oomem(ms, sizeof(*mp) * maxmagic); return -1; } (void)memset(&mp[*nmentryp], 0, sizeof(*mp) * ALLOC_INCR); *mentryp = mp; } me = &(*mentryp)[*nmentryp]; if (me->mp == NULL) { size_t len = sizeof(*m) * ALLOC_CHUNK; if ((m = CAST(struct magic *, malloc(len))) == NULL) { file_oomem(ms, len); return -1; } me->mp = m; me->max_count = ALLOC_CHUNK; } else m = me->mp; (void)memset(m, 0, sizeof(*m)); m->factor_op = FILE_FACTOR_OP_NONE; m->cont_level = 0; me->cont_count = 1; } m->lineno = CAST(uint32_t, lineno); if (*l == '&') { /* m->cont_level == 0 checked below. */ ++l; /* step over */ m->flag |= OFFADD; } if (*l == '(') { ++l; /* step over */ m->flag |= INDIR; if (m->flag & OFFADD) m->flag = (m->flag & ~OFFADD) | INDIROFFADD; if (*l == '&') { /* m->cont_level == 0 checked below */ ++l; /* step over */ m->flag |= OFFADD; } } /* Indirect offsets are not valid at level 0. */ if (m->cont_level == 0 && (m->flag & (OFFADD | INDIROFFADD))) if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "relative offset at level 0"); /* get offset, then skip over it */ m->offset = (uint32_t)strtoul(l, &t, 0); if (l == t) if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "offset `%s' invalid", l); l = t; if (m->flag & INDIR) { m->in_type = FILE_LONG; m->in_offset = 0; /* * read [.lbs][+-]nnnnn) */ if (*l == '.') { l++; switch (*l) { case 'l': m->in_type = FILE_LELONG; break; case 'L': m->in_type = FILE_BELONG; break; case 'm': m->in_type = FILE_MELONG; break; case 'h': case 's': m->in_type = FILE_LESHORT; break; case 'H': case 'S': m->in_type = FILE_BESHORT; break; case 'c': case 'b': case 'C': case 'B': m->in_type = FILE_BYTE; break; case 'e': case 'f': case 'g': m->in_type = FILE_LEDOUBLE; break; case 'E': case 'F': case 'G': m->in_type = FILE_BEDOUBLE; break; case 'i': m->in_type = FILE_LEID3; break; case 'I': m->in_type = FILE_BEID3; break; default: if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "indirect offset type `%c' invalid", *l); break; } l++; } m->in_op = 0; if (*l == '~') { m->in_op |= FILE_OPINVERSE; l++; } if ((op = get_op(*l)) != -1) { m->in_op |= op; l++; } if (*l == '(') { m->in_op |= FILE_OPINDIRECT; l++; } if (isdigit((unsigned char)*l) || *l == '-') { m->in_offset = (int32_t)strtol(l, &t, 0); if (l == t) if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "in_offset `%s' invalid", l); l = t; } if (*l++ != ')' || ((m->in_op & FILE_OPINDIRECT) && *l++ != ')')) if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "missing ')' in indirect offset"); } EATAB; #ifdef ENABLE_CONDITIONALS m->cond = get_cond(l, &l); if (check_cond(ms, m->cond, cont_level) == -1) return -1; EATAB; #endif if (*l == 'u') { ++l; m->flag |= UNSIGNED; } m->type = get_type(l, &l); if (m->type == FILE_INVALID) { if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "type `%s' invalid", l); return -1; } /* New-style anding: "0 byte&0x80 =0x80 dynamically linked" */ /* New and improved: ~ & | ^ + - * / % -- exciting, isn't it? */ m->mask_op = 0; if (*l == '~') { if (!IS_STRING(m->type)) m->mask_op |= FILE_OPINVERSE; else if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "'~' invalid for string types"); ++l; } m->str_range = 0; m->str_flags = m->type == FILE_PSTRING ? PSTRING_1_LE : 0; if ((op = get_op(*l)) != -1) { if (!IS_STRING(m->type)) { uint64_t val; ++l; m->mask_op |= op; val = (uint64_t)strtoull(l, &t, 0); l = t; m->num_mask = file_signextend(ms, m, val); eatsize(&l); } else if (op == FILE_OPDIVIDE) { int have_range = 0; while (!isspace((unsigned char)*++l)) { switch (*l) { case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': if (have_range && (ms->flags & MAGIC_CHECK)) file_magwarn(ms, "multiple ranges"); have_range = 1; m->str_range = CAST(uint32_t, strtoul(l, &t, 0)); if (m->str_range == 0) file_magwarn(ms, "zero range"); l = t - 1; break; case CHAR_COMPACT_WHITESPACE: m->str_flags |= STRING_COMPACT_WHITESPACE; break; case CHAR_COMPACT_OPTIONAL_WHITESPACE: m->str_flags |= STRING_COMPACT_OPTIONAL_WHITESPACE; break; case CHAR_IGNORE_LOWERCASE: m->str_flags |= STRING_IGNORE_LOWERCASE; break; case CHAR_IGNORE_UPPERCASE: m->str_flags |= STRING_IGNORE_UPPERCASE; break; case CHAR_REGEX_OFFSET_START: m->str_flags |= REGEX_OFFSET_START; break; case CHAR_BINTEST: m->str_flags |= STRING_BINTEST; break; case CHAR_TEXTTEST: m->str_flags |= STRING_TEXTTEST; break; case CHAR_PSTRING_1_LE: if (m->type != FILE_PSTRING) goto bad; m->str_flags = (m->str_flags & ~PSTRING_LEN) | PSTRING_1_LE; break; case CHAR_PSTRING_2_BE: if (m->type != FILE_PSTRING) goto bad; m->str_flags = (m->str_flags & ~PSTRING_LEN) | PSTRING_2_BE; break; case CHAR_PSTRING_2_LE: if (m->type != FILE_PSTRING) goto bad; m->str_flags = (m->str_flags & ~PSTRING_LEN) | PSTRING_2_LE; break; case CHAR_PSTRING_4_BE: if (m->type != FILE_PSTRING) goto bad; m->str_flags = (m->str_flags & ~PSTRING_LEN) | PSTRING_4_BE; break; case CHAR_PSTRING_4_LE: if (m->type != FILE_PSTRING) goto bad; m->str_flags = (m->str_flags & ~PSTRING_LEN) | PSTRING_4_LE; break; case CHAR_PSTRING_LENGTH_INCLUDES_ITSELF: if (m->type != FILE_PSTRING) goto bad; m->str_flags |= PSTRING_LENGTH_INCLUDES_ITSELF; break; bad: default: if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "string extension `%c' " "invalid", *l); return -1; } /* allow multiple '/' for readability */ if (l[1] == '/' && !isspace((unsigned char)l[2])) l++; } if (string_modifier_check(ms, m) == -1) return -1; } else { if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "invalid string op: %c", *t); return -1; } } /* * We used to set mask to all 1's here, instead let's just not do * anything if mask = 0 (unless you have a better idea) */ EATAB; switch (*l) { case '>': case '<': m->reln = *l; ++l; if (*l == '=') { if (ms->flags & MAGIC_CHECK) { file_magwarn(ms, "%c= not supported", m->reln); return -1; } ++l; } break; /* Old-style anding: "0 byte &0x80 dynamically linked" */ case '&': case '^': case '=': m->reln = *l; ++l; if (*l == '=') { /* HP compat: ignore &= etc. */ ++l; } break; case '!': m->reln = *l; ++l; break; default: m->reln = '='; /* the default relation */ if (*l == 'x' && ((isascii((unsigned char)l[1]) && isspace((unsigned char)l[1])) || !l[1])) { m->reln = *l; ++l; } break; } /* * Grab the value part, except for an 'x' reln. */ if (m->reln != 'x' && getvalue(ms, m, &l, action)) return -1; /* * TODO finish this macro and start using it! * #define offsetcheck {if (offset > HOWMANY-1) * magwarn("offset too big"); } */ /* * Now get last part - the description */ EATAB; if (l[0] == '\b') { ++l; m->flag |= NOSPACE; } else if ((l[0] == '\\') && (l[1] == 'b')) { ++l; ++l; m->flag |= NOSPACE; } for (i = 0; (m->desc[i++] = *l++) != '\0' && i < sizeof(m->desc); ) continue; if (i == sizeof(m->desc)) { m->desc[sizeof(m->desc) - 1] = '\0'; if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "description `%s' truncated", m->desc); } /* * We only do this check while compiling, or if any of the magic * files were not compiled. */ if (ms->flags & MAGIC_CHECK) { if (check_format(ms, m) == -1) return -1; } #ifndef COMPILE_ONLY if (action == FILE_CHECK) { file_mdump(m); } #endif m->mimetype[0] = '\0'; /* initialise MIME type to none */ if (m->cont_level == 0) ++(*nmentryp); /* make room for next */ return 0; } /* * parse a STRENGTH annotation line from magic file, put into magic[index - 1] * if valid */ private int parse_strength(struct magic_set *ms, struct magic_entry *me, const char *line) { const char *l = line; char *el; unsigned long factor; struct magic *m = &me->mp[0]; if (m->factor_op != FILE_FACTOR_OP_NONE) { file_magwarn(ms, "Current entry already has a strength type: %c %d", m->factor_op, m->factor); return -1; } EATAB; switch (*l) { case FILE_FACTOR_OP_NONE: case FILE_FACTOR_OP_PLUS: case FILE_FACTOR_OP_MINUS: case FILE_FACTOR_OP_TIMES: case FILE_FACTOR_OP_DIV: m->factor_op = *l++; break; default: file_magwarn(ms, "Unknown factor op `%c'", *l); return -1; } EATAB; factor = strtoul(l, &el, 0); if (factor > 255) { file_magwarn(ms, "Too large factor `%lu'", factor); goto out; } if (*el && !isspace((unsigned char)*el)) { file_magwarn(ms, "Bad factor `%s'", l); goto out; } m->factor = (uint8_t)factor; if (m->factor == 0 && m->factor_op == FILE_FACTOR_OP_DIV) { file_magwarn(ms, "Cannot have factor op `%c' and factor %u", m->factor_op, m->factor); goto out; } return 0; out: m->factor_op = FILE_FACTOR_OP_NONE; m->factor = 0; return -1; } /* * Parse an Apple CREATOR/TYPE annotation from magic file and put it into * magic[index - 1] */ private int parse_apple(struct magic_set *ms, struct magic_entry *me, const char *line) { size_t i; const char *l = line; struct magic *m = &me->mp[me->cont_count == 0 ? 0 : me->cont_count - 1]; if (m->apple[0] != '\0') { file_magwarn(ms, "Current entry already has a APPLE type " "`%.8s', new type `%s'", m->mimetype, l); return -1; } EATAB; for (i = 0; *l && ((isascii((unsigned char)*l) && isalnum((unsigned char)*l)) || strchr("-+/.", *l)) && i < sizeof(m->apple); m->apple[i++] = *l++) continue; if (i == sizeof(m->apple) && *l) { /* We don't need to NUL terminate here, printing handles it */ if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "APPLE type `%s' truncated %" SIZE_T_FORMAT "u", line, i); } if (i > 0) return 0; else return -1; } /* * parse a MIME annotation line from magic file, put into magic[index - 1] * if valid */ private int parse_mime(struct magic_set *ms, struct magic_entry *me, const char *line) { size_t i; const char *l = line; struct magic *m = &me->mp[me->cont_count == 0 ? 0 : me->cont_count - 1]; if (m->mimetype[0] != '\0') { file_magwarn(ms, "Current entry already has a MIME type `%s'," " new type `%s'", m->mimetype, l); return -1; } EATAB; for (i = 0; *l && ((isascii((unsigned char)*l) && isalnum((unsigned char)*l)) || strchr("-+/.", *l)) && i < sizeof(m->mimetype); m->mimetype[i++] = *l++) continue; if (i == sizeof(m->mimetype)) { m->mimetype[sizeof(m->mimetype) - 1] = '\0'; if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "MIME type `%s' truncated %" SIZE_T_FORMAT "u", m->mimetype, i); } else m->mimetype[i] = '\0'; if (i > 0) return 0; else return -1; } private int check_format_type(const char *ptr, int type) { int quad = 0; if (*ptr == '\0') { /* Missing format string; bad */ return -1; } switch (type) { case FILE_FMT_QUAD: quad = 1; /*FALLTHROUGH*/ case FILE_FMT_NUM: if (*ptr == '-') ptr++; if (*ptr == '.') ptr++; while (isdigit((unsigned char)*ptr)) ptr++; if (*ptr == '.') ptr++; while (isdigit((unsigned char)*ptr)) ptr++; if (quad) { if (*ptr++ != 'l') return -1; if (*ptr++ != 'l') return -1; } switch (*ptr++) { case 'l': switch (*ptr++) { case 'i': case 'd': case 'u': case 'x': case 'X': return 0; default: return -1; } case 'h': switch (*ptr++) { case 'h': switch (*ptr++) { case 'i': case 'd': case 'u': case 'x': case 'X': return 0; default: return -1; } case 'd': return 0; default: return -1; } case 'i': case 'c': case 'd': case 'u': case 'x': case 'X': return 0; default: return -1; } case FILE_FMT_FLOAT: case FILE_FMT_DOUBLE: if (*ptr == '-') ptr++; if (*ptr == '.') ptr++; while (isdigit((unsigned char)*ptr)) ptr++; if (*ptr == '.') ptr++; while (isdigit((unsigned char)*ptr)) ptr++; switch (*ptr++) { case 'e': case 'E': case 'f': case 'F': case 'g': case 'G': return 0; default: return -1; } case FILE_FMT_STR: if (*ptr == '-') ptr++; while (isdigit((unsigned char )*ptr)) ptr++; if (*ptr == '.') { ptr++; while (isdigit((unsigned char )*ptr)) ptr++; } switch (*ptr++) { case 's': return 0; default: return -1; } default: /* internal error */ abort(); } /*NOTREACHED*/ return -1; } /* * Check that the optional printf format in description matches * the type of the magic. */ private int check_format(struct magic_set *ms, struct magic *m) { char *ptr; for (ptr = m->desc; *ptr; ptr++) if (*ptr == '%') break; if (*ptr == '\0') { /* No format string; ok */ return 1; } assert(file_nformats == file_nnames); if (m->type >= file_nformats) { file_magwarn(ms, "Internal error inconsistency between " "m->type and format strings"); return -1; } if (file_formats[m->type] == FILE_FMT_NONE) { file_magwarn(ms, "No format string for `%s' with description " "`%s'", m->desc, file_names[m->type]); return -1; } ptr++; if (check_format_type(ptr, file_formats[m->type]) == -1) { /* * TODO: this error message is unhelpful if the format * string is not one character long */ file_magwarn(ms, "Printf format `%c' is not valid for type " "`%s' in description `%s'", *ptr ? *ptr : '?', file_names[m->type], m->desc); return -1; } for (; *ptr; ptr++) { if (*ptr == '%') { file_magwarn(ms, "Too many format strings (should have at most one) " "for `%s' with description `%s'", file_names[m->type], m->desc); return -1; } } return 0; } /* * Read a numeric value from a pointer, into the value union of a magic * pointer, according to the magic type. Update the string pointer to point * just after the number read. Return 0 for success, non-zero for failure. */ private int getvalue(struct magic_set *ms, struct magic *m, const char **p, int action) { switch (m->type) { case FILE_BESTRING16: case FILE_LESTRING16: case FILE_STRING: case FILE_PSTRING: case FILE_REGEX: case FILE_SEARCH: *p = getstr(ms, m, *p, action == FILE_COMPILE); if (*p == NULL) { if (ms->flags & MAGIC_CHECK) file_magwarn(ms, "cannot get string from `%s'", m->value.s); return -1; } return 0; case FILE_FLOAT: case FILE_BEFLOAT: case FILE_LEFLOAT: if (m->reln != 'x') { char *ep; #ifdef HAVE_STRTOF m->value.f = strtof(*p, &ep); #else m->value.f = (float)strtod(*p, &ep); #endif *p = ep; } return 0; case FILE_DOUBLE: case FILE_BEDOUBLE: case FILE_LEDOUBLE: if (m->reln != 'x') { char *ep; m->value.d = strtod(*p, &ep); *p = ep; } return 0; default: if (m->reln != 'x') { char *ep; m->value.q = file_signextend(ms, m, (uint64_t)strtoull(*p, &ep, 0)); *p = ep; eatsize(p); } return 0; } } /* * Convert a string containing C character escapes. Stop at an unescaped * space or tab. * Copy the converted version to "m->value.s", and the length in m->vallen. * Return updated scan pointer as function result. Warn if set. */ private const char * getstr(struct magic_set *ms, struct magic *m, const char *s, int warn) { const char *origs = s; char *p = m->value.s; size_t plen = sizeof(m->value.s); char *origp = p; char *pmax = p + plen - 1; int c; int val; while ((c = *s++) != '\0') { if (isspace((unsigned char) c)) break; if (p >= pmax) { file_error(ms, 0, "string too long: `%s'", origs); return NULL; } if (c == '\\') { switch(c = *s++) { case '\0': if (warn) file_magwarn(ms, "incomplete escape"); goto out; case '\t': if (warn) { file_magwarn(ms, "escaped tab found, use \\t instead"); warn = 0; /* already did */ } /*FALLTHROUGH*/ default: if (warn) { if (isprint((unsigned char)c)) { /* Allow escaping of * ``relations'' */ if (strchr("<>&^=!", c) == NULL && (m->type != FILE_REGEX || strchr("[]().*?^$|{}", c) == NULL)) { file_magwarn(ms, "no " "need to escape " "`%c'", c); } } else { file_magwarn(ms, "unknown escape sequence: " "\\%03o", c); } } /*FALLTHROUGH*/ /* space, perhaps force people to use \040? */ case ' ': #if 0 /* * Other things people escape, but shouldn't need to, * so we disallow them */ case '\'': case '"': case '?': #endif /* Relations */ case '>': case '<': case '&': case '^': case '=': case '!': /* and baskslash itself */ case '\\': *p++ = (char) c; break; case 'a': *p++ = '\a'; break; case 'b': *p++ = '\b'; break; case 'f': *p++ = '\f'; break; case 'n': *p++ = '\n'; break; case 'r': *p++ = '\r'; break; case 't': *p++ = '\t'; break; case 'v': *p++ = '\v'; break; /* \ and up to 3 octal digits */ case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': val = c - '0'; c = *s++; /* try for 2 */ if (c >= '0' && c <= '7') { val = (val << 3) | (c - '0'); c = *s++; /* try for 3 */ if (c >= '0' && c <= '7') val = (val << 3) | (c-'0'); else --s; } else --s; *p++ = (char)val; break; /* \x and up to 2 hex digits */ case 'x': val = 'x'; /* Default if no digits */ c = hextoint(*s++); /* Get next char */ if (c >= 0) { val = c; c = hextoint(*s++); if (c >= 0) val = (val << 4) + c; else --s; } else --s; *p++ = (char)val; break; } } else *p++ = (char)c; } out: *p = '\0'; m->vallen = CAST(unsigned char, (p - origp)); if (m->type == FILE_PSTRING) m->vallen += file_pstring_length_size(m); return s; } /* Single hex char to int; -1 if not a hex char. */ private int hextoint(int c) { if (!isascii((unsigned char) c)) return -1; if (isdigit((unsigned char) c)) return c - '0'; if ((c >= 'a') && (c <= 'f')) return c + 10 - 'a'; if (( c>= 'A') && (c <= 'F')) return c + 10 - 'A'; return -1; } /* * Print a string containing C character escapes. */ protected void file_showstr(FILE *fp, const char *s, size_t len) { char c; for (;;) { if (len == ~0U) { c = *s++; if (c == '\0') break; } else { if (len-- == 0) break; c = *s++; } if (c >= 040 && c <= 0176) /* TODO isprint && !iscntrl */ (void) fputc(c, fp); else { (void) fputc('\\', fp); switch (c) { case '\a': (void) fputc('a', fp); break; case '\b': (void) fputc('b', fp); break; case '\f': (void) fputc('f', fp); break; case '\n': (void) fputc('n', fp); break; case '\r': (void) fputc('r', fp); break; case '\t': (void) fputc('t', fp); break; case '\v': (void) fputc('v', fp); break; default: (void) fprintf(fp, "%.3o", c & 0377); break; } } } } /* * eatsize(): Eat the size spec from a number [eg. 10UL] */ private void eatsize(const char **p) { const char *l = *p; if (LOWCASE(*l) == 'u') l++; switch (LOWCASE(*l)) { case 'l': /* long */ case 's': /* short */ case 'h': /* short */ case 'b': /* char/byte */ case 'c': /* char/byte */ l++; /*FALLTHROUGH*/ default: break; } *p = l; } /* * handle a compiled file. */ private int apprentice_map(struct magic_set *ms, struct magic **magicp, uint32_t *nmagicp, const char *fn) { int fd; struct stat st; uint32_t *ptr; uint32_t version; int needsbyteswap; char *dbname = NULL; void *mm = NULL; dbname = mkdbname(ms, fn, 0); if (dbname == NULL) goto error2; if ((fd = open(dbname, O_RDONLY|O_BINARY)) == -1) goto error2; if (fstat(fd, &st) == -1) { file_error(ms, errno, "cannot stat `%s'", dbname); goto error1; } if (st.st_size < 8) { file_error(ms, 0, "file `%s' is too small", dbname); goto error1; } #ifdef QUICK if ((mm = mmap(0, (size_t)st.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FILE, fd, (off_t)0)) == MAP_FAILED) { file_error(ms, errno, "cannot map `%s'", dbname); goto error1; } #define RET 2 #else if ((mm = CAST(void *, malloc((size_t)st.st_size))) == NULL) { file_oomem(ms, (size_t)st.st_size); goto error1; } if (read(fd, mm, (size_t)st.st_size) != (ssize_t)st.st_size) { file_badread(ms); goto error1; } #define RET 1 #endif *magicp = CAST(struct magic *, mm); (void)close(fd); fd = -1; ptr = (uint32_t *)(void *)*magicp; if (*ptr != MAGICNO) { if (swap4(*ptr) != MAGICNO) { file_error(ms, 0, "bad magic in `%s'", dbname); goto error1; } needsbyteswap = 1; } else needsbyteswap = 0; if (needsbyteswap) version = swap4(ptr[1]); else version = ptr[1]; if (version != VERSIONNO) { file_error(ms, 0, "File %s supports only version %d magic " "files. `%s' is version %d", VERSION, VERSIONNO, dbname, version); goto error1; } *nmagicp = (uint32_t)(st.st_size / sizeof(struct magic)); if (*nmagicp > 0) (*nmagicp)--; (*magicp)++; if (needsbyteswap) byteswap(*magicp, *nmagicp); free(dbname); return RET; error1: if (fd != -1) (void)close(fd); if (mm) { #ifdef QUICK (void)munmap((void *)mm, (size_t)st.st_size); #else free(mm); #endif } else { *magicp = NULL; *nmagicp = 0; } error2: free(dbname); return -1; } private const uint32_t ar[] = { MAGICNO, VERSIONNO }; /* * handle an mmaped file. */ private int apprentice_compile(struct magic_set *ms, struct magic **magicp, uint32_t *nmagicp, const char *fn) { int fd; char *dbname; int rv = -1; dbname = mkdbname(ms, fn, 1); if (dbname == NULL) goto out; if ((fd = open(dbname, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY, 0644)) == -1) { file_error(ms, errno, "cannot open `%s'", dbname); goto out; } if (write(fd, ar, sizeof(ar)) != (ssize_t)sizeof(ar)) { file_error(ms, errno, "error writing `%s'", dbname); goto out; } if (lseek(fd, (off_t)sizeof(struct magic), SEEK_SET) != sizeof(struct magic)) { file_error(ms, errno, "error seeking `%s'", dbname); goto out; } if (write(fd, *magicp, (sizeof(struct magic) * *nmagicp)) != (ssize_t)(sizeof(struct magic) * *nmagicp)) { file_error(ms, errno, "error writing `%s'", dbname); goto out; } (void)close(fd); rv = 0; out: free(dbname); return rv; } private const char ext[] = ".mgc"; /* * make a dbname */ private char * mkdbname(struct magic_set *ms, const char *fn, int strip) { const char *p, *q; char *buf; if (strip) { if ((p = strrchr(fn, '/')) != NULL) fn = ++p; } for (q = fn; *q; q++) continue; /* Look for .mgc */ for (p = ext + sizeof(ext) - 1; p >= ext && q >= fn; p--, q--) if (*p != *q) break; /* Did not find .mgc, restore q */ if (p >= ext) while (*q) q++; q++; /* Compatibility with old code that looked in .mime */ if (ms->flags & MAGIC_MIME) { asprintf(&buf, "%.*s.mime%s", (int)(q - fn), fn, ext); if (access(buf, R_OK) != -1) { ms->flags &= MAGIC_MIME_TYPE; return buf; } free(buf); } asprintf(&buf, "%.*s%s", (int)(q - fn), fn, ext); /* Compatibility with old code that looked in .mime */ if (strstr(p, ".mime") != NULL) ms->flags &= MAGIC_MIME_TYPE; return buf; } /* * Byteswap an mmap'ed file if needed */ private void byteswap(struct magic *magic, uint32_t nmagic) { uint32_t i; for (i = 0; i < nmagic; i++) bs1(&magic[i]); } /* * swap a short */ private uint16_t swap2(uint16_t sv) { uint16_t rv; uint8_t *s = (uint8_t *)(void *)&sv; uint8_t *d = (uint8_t *)(void *)&rv; d[0] = s[1]; d[1] = s[0]; return rv; } /* * swap an int */ private uint32_t swap4(uint32_t sv) { uint32_t rv; uint8_t *s = (uint8_t *)(void *)&sv; uint8_t *d = (uint8_t *)(void *)&rv; d[0] = s[3]; d[1] = s[2]; d[2] = s[1]; d[3] = s[0]; return rv; } /* * swap a quad */ private uint64_t swap8(uint64_t sv) { uint64_t rv; uint8_t *s = (uint8_t *)(void *)&sv; uint8_t *d = (uint8_t *)(void *)&rv; #if 0 d[0] = s[3]; d[1] = s[2]; d[2] = s[1]; d[3] = s[0]; d[4] = s[7]; d[5] = s[6]; d[6] = s[5]; d[7] = s[4]; #else d[0] = s[7]; d[1] = s[6]; d[2] = s[5]; d[3] = s[4]; d[4] = s[3]; d[5] = s[2]; d[6] = s[1]; d[7] = s[0]; #endif return rv; } /* * byteswap a single magic entry */ private void bs1(struct magic *m) { m->cont_level = swap2(m->cont_level); m->offset = swap4((uint32_t)m->offset); m->in_offset = swap4((uint32_t)m->in_offset); m->lineno = swap4((uint32_t)m->lineno); if (IS_STRING(m->type)) { m->str_range = swap4(m->str_range); m->str_flags = swap4(m->str_flags); } else { m->value.q = swap8(m->value.q); m->num_mask = swap8(m->num_mask); } } protected size_t file_pstring_length_size(const struct magic *m) { switch (m->str_flags & PSTRING_LEN) { case PSTRING_1_LE: return 1; case PSTRING_2_LE: case PSTRING_2_BE: return 2; case PSTRING_4_LE: case PSTRING_4_BE: return 4; default: abort(); /* Impossible */ return 1; } } protected size_t file_pstring_get_length(const struct magic *m, const char *s) { size_t len = 0; switch (m->str_flags & PSTRING_LEN) { case PSTRING_1_LE: len = *s; break; case PSTRING_2_LE: len = (s[1] << 8) | s[0]; break; case PSTRING_2_BE: len = (s[0] << 8) | s[1]; break; case PSTRING_4_LE: len = (s[3] << 24) | (s[2] << 16) | (s[1] << 8) | s[0]; break; case PSTRING_4_BE: len = (s[0] << 24) | (s[1] << 16) | (s[2] << 8) | s[3]; break; default: abort(); /* Impossible */ } if (m->str_flags & PSTRING_LENGTH_INCLUDES_ITSELF) len -= file_pstring_length_size(m); return len; }