/* $OpenBSD: softmagic.c,v 1.17 2013/04/17 15:01:26 deraadt Exp $ */ /* * 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. */ /* * softmagic - interpret variable magic from MAGIC */ #include "file.h" #include "magic.h" #include #include #include #include private int match(struct magic_set *, struct magic *, uint32_t, const unsigned char *, size_t, int); private int mget(struct magic_set *, const unsigned char *, struct magic *, size_t, unsigned int); private int magiccheck(struct magic_set *, struct magic *); private int32_t mprint(struct magic_set *, struct magic *); private void mdebug(uint32_t, const char *, size_t); private int mcopy(struct magic_set *, union VALUETYPE *, int, int, const unsigned char *, uint32_t, size_t, size_t); private int mconvert(struct magic_set *, struct magic *); private int print_sep(struct magic_set *, int); private void cvt_8(union VALUETYPE *, const struct magic *); private void cvt_16(union VALUETYPE *, const struct magic *); private void cvt_32(union VALUETYPE *, const struct magic *); private void cvt_64(union VALUETYPE *, const struct magic *); /* * Macro to give description string according to whether we want plain * text or MIME type */ #define MAGIC_DESC ((ms->flags & MAGIC_MIME) ? m->mimetype : m->desc) /* * softmagic - lookup one file in parsed, in-memory copy of database * Passed the name and FILE * of one file to be typed. */ /*ARGSUSED1*/ /* nbytes passed for regularity, maybe need later */ protected int file_softmagic(struct magic_set *ms, const unsigned char *buf, size_t nbytes, int mode) { struct mlist *ml; int rv; for (ml = ms->mlist->next; ml != ms->mlist; ml = ml->next) if ((rv = match(ms, ml->magic, ml->nmagic, buf, nbytes, mode)) != 0) return rv; return 0; } /* * Go through the whole list, stopping if you find a match. Process all * the continuations of that match before returning. * * We support multi-level continuations: * * At any time when processing a successful top-level match, there is a * current continuation level; it represents the level of the last * successfully matched continuation. * * Continuations above that level are skipped as, if we see one, it * means that the continuation that controls them - i.e, the * lower-level continuation preceding them - failed to match. * * Continuations below that level are processed as, if we see one, * it means we've finished processing or skipping higher-level * continuations under the control of a successful or unsuccessful * lower-level continuation, and are now seeing the next lower-level * continuation and should process it. The current continuation * level reverts to the level of the one we're seeing. * * Continuations at the current level are processed as, if we see * one, there's no lower-level continuation that may have failed. * * If a continuation matches, we bump the current continuation level * so that higher-level continuations are processed. */ private int match(struct magic_set *ms, struct magic *magic, uint32_t nmagic, const unsigned char *s, size_t nbytes, int mode) { uint32_t magindex = 0; unsigned int cont_level = 0; int need_separator = 0; int returnval = 0; /* if a match is found it is set to 1*/ int firstline = 1; /* a flag to print X\n X\n- X */ int printed_something = 0; if (file_check_mem(ms, cont_level) == -1) return -1; for (magindex = 0; magindex < nmagic; magindex++) { int flush; struct magic *m = &magic[magindex]; if ((m->flag & BINTEST) != mode) { /* Skip sub-tests */ while (magic[magindex + 1].cont_level != 0 && ++magindex < nmagic) continue; continue; /* Skip to next top-level test*/ } ms->offset = m->offset; ms->line = m->lineno; /* if main entry matches, print it... */ flush = !mget(ms, s, m, nbytes, cont_level); if (flush) { if (m->reln == '!') flush = 0; } else { switch (magiccheck(ms, m)) { case -1: return -1; case 0: flush++; break; default: break; } } if (flush) { /* * main entry didn't match, * flush its continuations */ while (magindex < nmagic - 1 && magic[magindex + 1].cont_level != 0) magindex++; continue; } /* * If we are going to print something, we'll need to print * a blank before we print something else. */ if (*MAGIC_DESC) { need_separator = 1; printed_something = 1; if (print_sep(ms, firstline) == -1) return -1; } if ((ms->c.li[cont_level].off = mprint(ms, m)) == -1) return -1; /* and any continuations that match */ if (file_check_mem(ms, ++cont_level) == -1) return -1; while (magic[magindex+1].cont_level != 0 && ++magindex < nmagic) { m = &magic[magindex]; ms->line = m->lineno; /* for messages */ if (cont_level < m->cont_level) continue; if (cont_level > m->cont_level) { /* * We're at the end of the level * "cont_level" continuations. */ cont_level = m->cont_level; } ms->offset = m->offset; if (m->flag & OFFADD) { ms->offset += ms->c.li[cont_level - 1].off; } #ifdef ENABLE_CONDITIONALS if (m->cond == COND_ELSE || m->cond == COND_ELIF) { if (ms->c.li[cont_level].last_match == 1) continue; } #endif flush = !mget(ms, s, m, nbytes, cont_level); if (flush && m->reln != '!') continue; switch (flush ? 1 : magiccheck(ms, m)) { case -1: return -1; case 0: #ifdef ENABLE_CONDITIONALS ms->c.li[cont_level].last_match = 0; #endif break; default: #ifdef ENABLE_CONDITIONALS ms->c.li[cont_level].last_match = 1; #endif if (m->type != FILE_DEFAULT) ms->c.li[cont_level].got_match = 1; else if (ms->c.li[cont_level].got_match) { ms->c.li[cont_level].got_match = 0; break; } /* * If we are going to print something, * make sure that we have a separator first. */ if (*MAGIC_DESC) { printed_something = 1; if (print_sep(ms, firstline) == -1) return -1; } /* * This continuation matched. Print * its message, with a blank before it * if the previous item printed and * this item isn't empty. */ /* space if previous printed */ if (need_separator && ((m->flag & NOSPACE) == 0) && *MAGIC_DESC) { if (file_printf(ms, " ") == -1) return -1; need_separator = 0; } if ((ms->c.li[cont_level].off = mprint(ms, m)) == -1) return -1; if (*MAGIC_DESC) need_separator = 1; /* * If we see any continuations * at a higher level, * process them. */ if (file_check_mem(ms, ++cont_level) == -1) return -1; break; } } if (printed_something) { firstline = 0; returnval = 1; } if ((ms->flags & MAGIC_CONTINUE) == 0 && printed_something) { return 1; /* don't keep searching */ } } return returnval; /* This is hit if -k is set or there is no match */ } private int check_fmt(struct magic_set *ms, struct magic *m) { regex_t rx; int rc; if (strchr(MAGIC_DESC, '%') == NULL) return 0; rc = regcomp(&rx, "%[-0-9\\.]*s", REG_EXTENDED|REG_NOSUB); if (rc) { char errmsg[512]; (void)regerror(rc, &rx, errmsg, sizeof(errmsg)); file_magerror(ms, "regex error %d, (%s)", rc, errmsg); return -1; } else { rc = regexec(&rx, MAGIC_DESC, 0, 0, 0); regfree(&rx); return !rc; } } #ifndef HAVE_STRNDUP char * strndup(const char *, size_t); char * strndup(const char *str, size_t n) { size_t len; char *copy; for (len = 0; len < n && str[len]; len++) continue; if ((copy = malloc(len + 1)) == NULL) return NULL; (void)memcpy(copy, str, len); copy[len] = '\0'; return copy; } #endif /* HAVE_STRNDUP */ private int32_t mprint(struct magic_set *ms, struct magic *m) { uint64_t v; float vf; double vd; int64_t t = 0; char *buf; union VALUETYPE *p = &ms->ms_value; switch (m->type) { case FILE_BYTE: v = file_signextend(ms, m, (uint64_t)p->b); switch (check_fmt(ms, m)) { case -1: return -1; case 1: if (asprintf(&buf, "%c", (unsigned char)v) < 0) return -1; if (file_printf(ms, MAGIC_DESC, buf) == -1) return -1; break; default: if (file_printf(ms, MAGIC_DESC, (unsigned char) v) == -1) return -1; break; } t = ms->offset + sizeof(char); break; case FILE_SHORT: case FILE_BESHORT: case FILE_LESHORT: v = file_signextend(ms, m, (uint64_t)p->h); switch (check_fmt(ms, m)) { case -1: return -1; case 1: if (asprintf(&buf, "%hu", (unsigned short)v) < 0) return -1; if (file_printf(ms, MAGIC_DESC, buf) == -1) return -1; break; default: if (file_printf(ms, MAGIC_DESC, (unsigned short) v) == -1) return -1; break; } t = ms->offset + sizeof(short); break; case FILE_LONG: case FILE_BELONG: case FILE_LELONG: case FILE_MELONG: v = file_signextend(ms, m, (uint64_t)p->l); switch (check_fmt(ms, m)) { case -1: return -1; case 1: if (asprintf(&buf, "%u", (uint32_t)v) < 0) return -1; if (file_printf(ms, MAGIC_DESC, buf) == -1) return -1; break; default: if (file_printf(ms, MAGIC_DESC, (uint32_t) v) == -1) return -1; break; } t = ms->offset + sizeof(int32_t); break; case FILE_QUAD: case FILE_BEQUAD: case FILE_LEQUAD: v = file_signextend(ms, m, p->q); if (file_printf(ms, MAGIC_DESC, (uint64_t) v) == -1) return -1; t = ms->offset + sizeof(int64_t); break; case FILE_STRING: case FILE_PSTRING: case FILE_BESTRING16: case FILE_LESTRING16: if (m->reln == '=' || m->reln == '!') { if (file_printf(ms, MAGIC_DESC, m->value.s) == -1) return -1; t = ms->offset + m->vallen; } else { if (*m->value.s == '\0') p->s[strcspn(p->s, "\n")] = '\0'; if (file_printf(ms, MAGIC_DESC, p->s) == -1) return -1; t = ms->offset + strlen(p->s); if (m->type == FILE_PSTRING) t++; } break; case FILE_DATE: case FILE_BEDATE: case FILE_LEDATE: case FILE_MEDATE: if (file_printf(ms, MAGIC_DESC, file_fmttime(p->l, 1)) == -1) return -1; t = ms->offset + sizeof(int32_t); break; case FILE_LDATE: case FILE_BELDATE: case FILE_LELDATE: case FILE_MELDATE: if (file_printf(ms, MAGIC_DESC, file_fmttime(p->l, 0)) == -1) return -1; t = ms->offset + sizeof(int32_t); break; case FILE_QDATE: case FILE_BEQDATE: case FILE_LEQDATE: if (file_printf(ms, MAGIC_DESC, file_fmttime(p->q, 1)) == -1) return -1; t = ms->offset + sizeof(uint64_t); break; case FILE_QLDATE: case FILE_BEQLDATE: case FILE_LEQLDATE: if (file_printf(ms, MAGIC_DESC, file_fmttime(p->q, 0)) == -1) return -1; t = ms->offset + sizeof(uint64_t); break; case FILE_FLOAT: case FILE_BEFLOAT: case FILE_LEFLOAT: vf = p->f; switch (check_fmt(ms, m)) { case -1: return -1; case 1: if (asprintf(&buf, "%g", vf) < 0) return -1; if (file_printf(ms, MAGIC_DESC, buf) == -1) return -1; break; default: if (file_printf(ms, MAGIC_DESC, vf) == -1) return -1; break; } t = ms->offset + sizeof(float); break; case FILE_DOUBLE: case FILE_BEDOUBLE: case FILE_LEDOUBLE: vd = p->d; switch (check_fmt(ms, m)) { case -1: return -1; case 1: if (asprintf(&buf, "%g", vd) < 0) return -1; if (file_printf(ms, MAGIC_DESC, buf) == -1) return -1; break; default: if (file_printf(ms, MAGIC_DESC, vd) == -1) return -1; break; } t = ms->offset + sizeof(double); break; case FILE_REGEX: { char *cp; int rval; cp = strndup((const char *)ms->search.s, ms->search.rm_len); if (cp == NULL) { file_oomem(ms, ms->search.rm_len); return -1; } rval = file_printf(ms, MAGIC_DESC, cp); free(cp); if (rval == -1) return -1; if ((m->str_flags & REGEX_OFFSET_START)) t = ms->search.offset; else t = ms->search.offset + ms->search.rm_len; break; } case FILE_SEARCH: if (file_printf(ms, MAGIC_DESC, m->value.s) == -1) return -1; if ((m->str_flags & REGEX_OFFSET_START)) t = ms->search.offset; else t = ms->search.offset + m->vallen; break; case FILE_DEFAULT: if (file_printf(ms, MAGIC_DESC, m->value.s) == -1) return -1; t = ms->offset; break; default: file_magerror(ms, "invalid m->type (%d) in mprint()", m->type); return -1; } return(t); } #define DO_CVT(fld, cast) \ if (m->num_mask) \ switch (m->mask_op & FILE_OPS_MASK) { \ case FILE_OPAND: \ p->fld &= cast m->num_mask; \ break; \ case FILE_OPOR: \ p->fld |= cast m->num_mask; \ break; \ case FILE_OPXOR: \ p->fld ^= cast m->num_mask; \ break; \ case FILE_OPADD: \ p->fld += cast m->num_mask; \ break; \ case FILE_OPMINUS: \ p->fld -= cast m->num_mask; \ break; \ case FILE_OPMULTIPLY: \ p->fld *= cast m->num_mask; \ break; \ case FILE_OPDIVIDE: \ p->fld /= cast m->num_mask; \ break; \ case FILE_OPMODULO: \ p->fld %= cast m->num_mask; \ break; \ } \ if (m->mask_op & FILE_OPINVERSE) \ p->fld = ~p->fld \ private void cvt_8(union VALUETYPE *p, const struct magic *m) { DO_CVT(b, (uint8_t)); } private void cvt_16(union VALUETYPE *p, const struct magic *m) { DO_CVT(h, (uint16_t)); } private void cvt_32(union VALUETYPE *p, const struct magic *m) { DO_CVT(l, (uint32_t)); } private void cvt_64(union VALUETYPE *p, const struct magic *m) { DO_CVT(q, (uint64_t)); } #define DO_CVT2(fld, cast) \ if (m->num_mask) \ switch (m->mask_op & FILE_OPS_MASK) { \ case FILE_OPADD: \ p->fld += cast m->num_mask; \ break; \ case FILE_OPMINUS: \ p->fld -= cast m->num_mask; \ break; \ case FILE_OPMULTIPLY: \ p->fld *= cast m->num_mask; \ break; \ case FILE_OPDIVIDE: \ p->fld /= cast m->num_mask; \ break; \ } \ private void cvt_float(union VALUETYPE *p, const struct magic *m) { DO_CVT2(f, (float)); } private void cvt_double(union VALUETYPE *p, const struct magic *m) { DO_CVT2(d, (double)); } /* * Convert the byte order of the data we are looking at * While we're here, let's apply the mask operation * (unless you have a better idea) */ private int mconvert(struct magic_set *ms, struct magic *m) { union VALUETYPE *p = &ms->ms_value; switch (m->type) { case FILE_BYTE: cvt_8(p, m); return 1; case FILE_SHORT: cvt_16(p, m); return 1; case FILE_LONG: case FILE_DATE: case FILE_LDATE: cvt_32(p, m); return 1; case FILE_QUAD: case FILE_QDATE: case FILE_QLDATE: cvt_64(p, m); return 1; case FILE_STRING: case FILE_BESTRING16: case FILE_LESTRING16: { size_t len; /* Null terminate and eat *trailing* return */ p->s[sizeof(p->s) - 1] = '\0'; len = strlen(p->s); if (len-- && p->s[len] == '\n') p->s[len] = '\0'; return 1; } case FILE_PSTRING: { char *ptr1 = p->s, *ptr2 = ptr1 + 1; size_t len = *p->s; if (len >= sizeof(p->s)) len = sizeof(p->s) - 1; while (len--) *ptr1++ = *ptr2++; *ptr1 = '\0'; len = strlen(p->s); if (len-- && p->s[len] == '\n') p->s[len] = '\0'; return 1; } case FILE_BESHORT: p->h = (short)((p->hs[0]<<8)|(p->hs[1])); cvt_16(p, m); return 1; case FILE_BELONG: case FILE_BEDATE: case FILE_BELDATE: p->l = (int32_t) ((p->hl[0]<<24)|(p->hl[1]<<16)|(p->hl[2]<<8)|(p->hl[3])); cvt_32(p, m); return 1; case FILE_BEQUAD: case FILE_BEQDATE: case FILE_BEQLDATE: p->q = (uint64_t) (((uint64_t)p->hq[0]<<56)|((uint64_t)p->hq[1]<<48)| ((uint64_t)p->hq[2]<<40)|((uint64_t)p->hq[3]<<32)| ((uint64_t)p->hq[4]<<24)|((uint64_t)p->hq[5]<<16)| ((uint64_t)p->hq[6]<<8)|((uint64_t)p->hq[7])); cvt_64(p, m); return 1; case FILE_LESHORT: p->h = (short)((p->hs[1]<<8)|(p->hs[0])); cvt_16(p, m); return 1; case FILE_LELONG: case FILE_LEDATE: case FILE_LELDATE: p->l = (int32_t) ((p->hl[3]<<24)|(p->hl[2]<<16)|(p->hl[1]<<8)|(p->hl[0])); cvt_32(p, m); return 1; case FILE_LEQUAD: case FILE_LEQDATE: case FILE_LEQLDATE: p->q = (uint64_t) (((uint64_t)p->hq[7]<<56)|((uint64_t)p->hq[6]<<48)| ((uint64_t)p->hq[5]<<40)|((uint64_t)p->hq[4]<<32)| ((uint64_t)p->hq[3]<<24)|((uint64_t)p->hq[2]<<16)| ((uint64_t)p->hq[1]<<8)|((uint64_t)p->hq[0])); cvt_64(p, m); return 1; case FILE_MELONG: case FILE_MEDATE: case FILE_MELDATE: p->l = (int32_t) ((p->hl[1]<<24)|(p->hl[0]<<16)|(p->hl[3]<<8)|(p->hl[2])); cvt_32(p, m); return 1; case FILE_FLOAT: cvt_float(p, m); return 1; case FILE_BEFLOAT: p->l = ((uint32_t)p->hl[0]<<24)|((uint32_t)p->hl[1]<<16)| ((uint32_t)p->hl[2]<<8) |((uint32_t)p->hl[3]); cvt_float(p, m); return 1; case FILE_LEFLOAT: p->l = ((uint32_t)p->hl[3]<<24)|((uint32_t)p->hl[2]<<16)| ((uint32_t)p->hl[1]<<8) |((uint32_t)p->hl[0]); cvt_float(p, m); return 1; case FILE_DOUBLE: cvt_double(p, m); return 1; case FILE_BEDOUBLE: p->q = ((uint64_t)p->hq[0]<<56)|((uint64_t)p->hq[1]<<48)| ((uint64_t)p->hq[2]<<40)|((uint64_t)p->hq[3]<<32)| ((uint64_t)p->hq[4]<<24)|((uint64_t)p->hq[5]<<16)| ((uint64_t)p->hq[6]<<8) |((uint64_t)p->hq[7]); cvt_double(p, m); return 1; case FILE_LEDOUBLE: p->q = ((uint64_t)p->hq[7]<<56)|((uint64_t)p->hq[6]<<48)| ((uint64_t)p->hq[5]<<40)|((uint64_t)p->hq[4]<<32)| ((uint64_t)p->hq[3]<<24)|((uint64_t)p->hq[2]<<16)| ((uint64_t)p->hq[1]<<8) |((uint64_t)p->hq[0]); cvt_double(p, m); return 1; case FILE_REGEX: case FILE_SEARCH: case FILE_DEFAULT: return 1; default: file_magerror(ms, "invalid type %d in mconvert()", m->type); return 0; } } private void mdebug(uint32_t offset, const char *str, size_t len) { (void) fprintf(stderr, "mget @%d: ", offset); file_showstr(stderr, str, len); (void) fputc('\n', stderr); (void) fputc('\n', stderr); } private int mcopy(struct magic_set *ms, union VALUETYPE *p, int type, int indir, const unsigned char *s, uint32_t offset, size_t nbytes, size_t linecnt) { /* * Note: FILE_SEARCH and FILE_REGEX do not actually copy * anything, but setup pointers into the source */ if (indir == 0) { switch (type) { case FILE_SEARCH: ms->search.s = (const char *)s + offset; ms->search.s_len = nbytes - offset; ms->search.offset = offset; return 0; case FILE_REGEX: { const char *b; const char *c; const char *last; /* end of search region */ const char *buf; /* start of search region */ size_t lines; if (s == NULL) { ms->search.s_len = 0; ms->search.s = NULL; return 0; } buf = (const char *)s + offset; last = (const char *)s + nbytes; /* mget() guarantees buf <= last */ for (lines = linecnt, b = buf; lines && ((b = strchr(c = b, '\n')) || (b = strchr(c, '\r'))); lines--, b++) { last = b; if (b[0] == '\r' && b[1] == '\n') b++; } if (lines) last = (const char *)s + nbytes; ms->search.s = buf; ms->search.s_len = last - buf; ms->search.offset = offset; ms->search.rm_len = 0; return 0; } case FILE_BESTRING16: case FILE_LESTRING16: { const unsigned char *src = s + offset; const unsigned char *esrc = s + nbytes; char *dst = p->s; char *edst = &p->s[sizeof(p->s) - 1]; if (type == FILE_BESTRING16) src++; /* check for pointer overflow */ if (src < s) { file_magerror(ms, "invalid offset %zu in mcopy()", offset); return -1; } for (/*EMPTY*/; src < esrc; src += 2, dst++) { if (dst < edst) *dst = *src; else break; if (*dst == '\0') { if (type == FILE_BESTRING16 ? *(src - 1) != '\0' : *(src + 1) != '\0') *dst = ' '; } } *edst = '\0'; return 0; } case FILE_STRING: /* XXX - these two should not need */ case FILE_PSTRING: /* to copy anything, but do anyway. */ default: break; } } if (offset >= nbytes) { (void)memset(p, '\0', sizeof(*p)); return 0; } if (nbytes - offset < sizeof(*p)) nbytes = nbytes - offset; else nbytes = sizeof(*p); (void)memcpy(p, s + offset, nbytes); /* * the usefulness of padding with zeroes eludes me, it * might even cause problems */ if (nbytes < sizeof(*p)) (void)memset(((char *)(void *)p) + nbytes, '\0', sizeof(*p) - nbytes); return 0; } private int mget(struct magic_set *ms, const unsigned char *s, struct magic *m, size_t nbytes, unsigned int cont_level) { uint32_t offset = ms->offset; uint32_t count = m->str_range; union VALUETYPE *p = &ms->ms_value; if (mcopy(ms, p, m->type, m->flag & INDIR, s, offset, nbytes, count) == -1) return -1; if ((ms->flags & MAGIC_DEBUG) != 0) { mdebug(offset, (char *)(void *)p, sizeof(union VALUETYPE)); file_mdump(m); } if (m->flag & INDIR) { int off = m->in_offset; if (m->in_op & FILE_OPINDIRECT) { const union VALUETYPE *q = ((const void *)(s + offset + off)); switch (m->in_type) { case FILE_BYTE: off = q->b; break; case FILE_SHORT: off = q->h; break; case FILE_BESHORT: off = (short)((q->hs[0]<<8)|(q->hs[1])); break; case FILE_LESHORT: off = (short)((q->hs[1]<<8)|(q->hs[0])); break; case FILE_LONG: off = q->l; break; case FILE_BELONG: off = (int32_t)((q->hl[0]<<24)|(q->hl[1]<<16)| (q->hl[2]<<8)|(q->hl[3])); break; case FILE_LELONG: off = (int32_t)((q->hl[3]<<24)|(q->hl[2]<<16)| (q->hl[1]<<8)|(q->hl[0])); break; case FILE_MELONG: off = (int32_t)((q->hl[1]<<24)|(q->hl[0]<<16)| (q->hl[3]<<8)|(q->hl[2])); break; } } switch (m->in_type) { case FILE_BYTE: if (nbytes < (offset + 1)) return 0; if (off) { switch (m->in_op & FILE_OPS_MASK) { case FILE_OPAND: offset = p->b & off; break; case FILE_OPOR: offset = p->b | off; break; case FILE_OPXOR: offset = p->b ^ off; break; case FILE_OPADD: offset = p->b + off; break; case FILE_OPMINUS: offset = p->b - off; break; case FILE_OPMULTIPLY: offset = p->b * off; break; case FILE_OPDIVIDE: offset = p->b / off; break; case FILE_OPMODULO: offset = p->b % off; break; } } else offset = p->b; if (m->in_op & FILE_OPINVERSE) offset = ~offset; break; case FILE_BESHORT: if (nbytes < (offset + 2)) return 0; if (off) { switch (m->in_op & FILE_OPS_MASK) { case FILE_OPAND: offset = (short)((p->hs[0]<<8)| (p->hs[1])) & off; break; case FILE_OPOR: offset = (short)((p->hs[0]<<8)| (p->hs[1])) | off; break; case FILE_OPXOR: offset = (short)((p->hs[0]<<8)| (p->hs[1])) ^ off; break; case FILE_OPADD: offset = (short)((p->hs[0]<<8)| (p->hs[1])) + off; break; case FILE_OPMINUS: offset = (short)((p->hs[0]<<8)| (p->hs[1])) - off; break; case FILE_OPMULTIPLY: offset = (short)((p->hs[0]<<8)| (p->hs[1])) * off; break; case FILE_OPDIVIDE: offset = (short)((p->hs[0]<<8)| (p->hs[1])) / off; break; case FILE_OPMODULO: offset = (short)((p->hs[0]<<8)| (p->hs[1])) % off; break; } } else offset = (short)((p->hs[0]<<8)| (p->hs[1])); if (m->in_op & FILE_OPINVERSE) offset = ~offset; break; case FILE_LESHORT: if (nbytes < (offset + 2)) return 0; if (off) { switch (m->in_op & FILE_OPS_MASK) { case FILE_OPAND: offset = (short)((p->hs[1]<<8)| (p->hs[0])) & off; break; case FILE_OPOR: offset = (short)((p->hs[1]<<8)| (p->hs[0])) | off; break; case FILE_OPXOR: offset = (short)((p->hs[1]<<8)| (p->hs[0])) ^ off; break; case FILE_OPADD: offset = (short)((p->hs[1]<<8)| (p->hs[0])) + off; break; case FILE_OPMINUS: offset = (short)((p->hs[1]<<8)| (p->hs[0])) - off; break; case FILE_OPMULTIPLY: offset = (short)((p->hs[1]<<8)| (p->hs[0])) * off; break; case FILE_OPDIVIDE: offset = (short)((p->hs[1]<<8)| (p->hs[0])) / off; break; case FILE_OPMODULO: offset = (short)((p->hs[1]<<8)| (p->hs[0])) % off; break; } } else offset = (short)((p->hs[1]<<8)| (p->hs[0])); if (m->in_op & FILE_OPINVERSE) offset = ~offset; break; case FILE_SHORT: if (nbytes < (offset + 2)) return 0; if (off) { switch (m->in_op & FILE_OPS_MASK) { case FILE_OPAND: offset = p->h & off; break; case FILE_OPOR: offset = p->h | off; break; case FILE_OPXOR: offset = p->h ^ off; break; case FILE_OPADD: offset = p->h + off; break; case FILE_OPMINUS: offset = p->h - off; break; case FILE_OPMULTIPLY: offset = p->h * off; break; case FILE_OPDIVIDE: offset = p->h / off; break; case FILE_OPMODULO: offset = p->h % off; break; } } else offset = p->h; if (m->in_op & FILE_OPINVERSE) offset = ~offset; break; case FILE_BELONG: if (nbytes < (offset + 4)) return 0; if (off) { switch (m->in_op & FILE_OPS_MASK) { case FILE_OPAND: offset = (int32_t)((p->hl[0]<<24)| (p->hl[1]<<16)| (p->hl[2]<<8)| (p->hl[3])) & off; break; case FILE_OPOR: offset = (int32_t)((p->hl[0]<<24)| (p->hl[1]<<16)| (p->hl[2]<<8)| (p->hl[3])) | off; break; case FILE_OPXOR: offset = (int32_t)((p->hl[0]<<24)| (p->hl[1]<<16)| (p->hl[2]<<8)| (p->hl[3])) ^ off; break; case FILE_OPADD: offset = (int32_t)((p->hl[0]<<24)| (p->hl[1]<<16)| (p->hl[2]<<8)| (p->hl[3])) + off; break; case FILE_OPMINUS: offset = (int32_t)((p->hl[0]<<24)| (p->hl[1]<<16)| (p->hl[2]<<8)| (p->hl[3])) - off; break; case FILE_OPMULTIPLY: offset = (int32_t)((p->hl[0]<<24)| (p->hl[1]<<16)| (p->hl[2]<<8)| (p->hl[3])) * off; break; case FILE_OPDIVIDE: offset = (int32_t)((p->hl[0]<<24)| (p->hl[1]<<16)| (p->hl[2]<<8)| (p->hl[3])) / off; break; case FILE_OPMODULO: offset = (int32_t)((p->hl[0]<<24)| (p->hl[1]<<16)| (p->hl[2]<<8)| (p->hl[3])) % off; break; } } else offset = (int32_t)((p->hl[0]<<24)| (p->hl[1]<<16)| (p->hl[2]<<8)| (p->hl[3])); if (m->in_op & FILE_OPINVERSE) offset = ~offset; break; case FILE_LELONG: if (nbytes < (offset + 4)) return 0; if (off) { switch (m->in_op & FILE_OPS_MASK) { case FILE_OPAND: offset = (int32_t)((p->hl[3]<<24)| (p->hl[2]<<16)| (p->hl[1]<<8)| (p->hl[0])) & off; break; case FILE_OPOR: offset = (int32_t)((p->hl[3]<<24)| (p->hl[2]<<16)| (p->hl[1]<<8)| (p->hl[0])) | off; break; case FILE_OPXOR: offset = (int32_t)((p->hl[3]<<24)| (p->hl[2]<<16)| (p->hl[1]<<8)| (p->hl[0])) ^ off; break; case FILE_OPADD: offset = (int32_t)((p->hl[3]<<24)| (p->hl[2]<<16)| (p->hl[1]<<8)| (p->hl[0])) + off; break; case FILE_OPMINUS: offset = (int32_t)((p->hl[3]<<24)| (p->hl[2]<<16)| (p->hl[1]<<8)| (p->hl[0])) - off; break; case FILE_OPMULTIPLY: offset = (int32_t)((p->hl[3]<<24)| (p->hl[2]<<16)| (p->hl[1]<<8)| (p->hl[0])) * off; break; case FILE_OPDIVIDE: offset = (int32_t)((p->hl[3]<<24)| (p->hl[2]<<16)| (p->hl[1]<<8)| (p->hl[0])) / off; break; case FILE_OPMODULO: offset = (int32_t)((p->hl[3]<<24)| (p->hl[2]<<16)| (p->hl[1]<<8)| (p->hl[0])) % off; break; } } else offset = (int32_t)((p->hl[3]<<24)| (p->hl[2]<<16)| (p->hl[1]<<8)| (p->hl[0])); if (m->in_op & FILE_OPINVERSE) offset = ~offset; break; case FILE_MELONG: if (nbytes < (offset + 4)) return 0; if (off) { switch (m->in_op & FILE_OPS_MASK) { case FILE_OPAND: offset = (int32_t)((p->hl[1]<<24)| (p->hl[0]<<16)| (p->hl[3]<<8)| (p->hl[2])) & off; break; case FILE_OPOR: offset = (int32_t)((p->hl[1]<<24)| (p->hl[0]<<16)| (p->hl[3]<<8)| (p->hl[2])) | off; break; case FILE_OPXOR: offset = (int32_t)((p->hl[1]<<24)| (p->hl[0]<<16)| (p->hl[3]<<8)| (p->hl[2])) ^ off; break; case FILE_OPADD: offset = (int32_t)((p->hl[1]<<24)| (p->hl[0]<<16)| (p->hl[3]<<8)| (p->hl[2])) + off; break; case FILE_OPMINUS: offset = (int32_t)((p->hl[1]<<24)| (p->hl[0]<<16)| (p->hl[3]<<8)| (p->hl[2])) - off; break; case FILE_OPMULTIPLY: offset = (int32_t)((p->hl[1]<<24)| (p->hl[0]<<16)| (p->hl[3]<<8)| (p->hl[2])) * off; break; case FILE_OPDIVIDE: offset = (int32_t)((p->hl[1]<<24)| (p->hl[0]<<16)| (p->hl[3]<<8)| (p->hl[2])) / off; break; case FILE_OPMODULO: offset = (int32_t)((p->hl[1]<<24)| (p->hl[0]<<16)| (p->hl[3]<<8)| (p->hl[2])) % off; break; } } else offset = (int32_t)((p->hl[1]<<24)| (p->hl[0]<<16)| (p->hl[3]<<8)| (p->hl[2])); if (m->in_op & FILE_OPINVERSE) offset = ~offset; break; case FILE_LONG: if (nbytes < (offset + 4)) return 0; if (off) { switch (m->in_op & FILE_OPS_MASK) { case FILE_OPAND: offset = p->l & off; break; case FILE_OPOR: offset = p->l | off; break; case FILE_OPXOR: offset = p->l ^ off; break; case FILE_OPADD: offset = p->l + off; break; case FILE_OPMINUS: offset = p->l - off; break; case FILE_OPMULTIPLY: offset = p->l * off; break; case FILE_OPDIVIDE: offset = p->l / off; break; case FILE_OPMODULO: offset = p->l % off; break; } } else offset = p->l; if (m->in_op & FILE_OPINVERSE) offset = ~offset; break; } if (m->flag & INDIROFFADD) offset += ms->c.li[cont_level-1].off; if (mcopy(ms, p, m->type, 0, s, offset, nbytes, count) == -1) return -1; ms->offset = offset; if ((ms->flags & MAGIC_DEBUG) != 0) { mdebug(offset, (char *)(void *)p, sizeof(union VALUETYPE)); file_mdump(m); } } /* Verify we have enough data to match magic type */ switch (m->type) { case FILE_BYTE: if (nbytes < (offset + 1)) /* should alway be true */ return 0; break; case FILE_SHORT: case FILE_BESHORT: case FILE_LESHORT: if (nbytes < (offset + 2)) return 0; break; case FILE_LONG: case FILE_BELONG: case FILE_LELONG: case FILE_MELONG: 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_FLOAT: case FILE_BEFLOAT: case FILE_LEFLOAT: if (nbytes < (offset + 4)) return 0; break; case FILE_DOUBLE: case FILE_BEDOUBLE: case FILE_LEDOUBLE: if (nbytes < (offset + 8)) return 0; break; case FILE_STRING: case FILE_PSTRING: case FILE_SEARCH: if (nbytes < (offset + m->vallen)) return 0; break; case FILE_REGEX: if (nbytes < offset) return 0; break; case FILE_DEFAULT: /* nothing to check */ default: break; } if (!mconvert(ms, m)) return 0; return 1; } private uint64_t file_strncmp(const char *s1, const char *s2, size_t len, uint32_t flags) { /* * Convert the source args to unsigned here so that (1) the * compare will be unsigned as it is in strncmp() and (2) so * the ctype functions will work correctly without extra * casting. */ const unsigned char *a = (const unsigned char *)s1; const unsigned char *b = (const unsigned char *)s2; uint64_t v; /* * What we want here is v = strncmp(s1, s2, len), * but ignoring any nulls. */ v = 0; if (0L == flags) { /* normal string: do it fast */ while (len-- > 0) if ((v = *b++ - *a++) != '\0') break; } else { /* combine the others */ while (len-- > 0) { if ((flags & STRING_IGNORE_LOWERCASE) && islower(*a)) { if ((v = tolower(*b++) - *a++) != '\0') break; } else if ((flags & STRING_IGNORE_UPPERCASE) && isupper(*a)) { if ((v = toupper(*b++) - *a++) != '\0') break; } else if ((flags & STRING_COMPACT_BLANK) && isspace(*a)) { a++; if (isspace(*b++)) { while (isspace(*b)) b++; } else { v = 1; break; } } else if ((flags & STRING_COMPACT_OPTIONAL_BLANK) && isspace(*a)) { a++; while (isspace(*b)) b++; } else { if ((v = *b++ - *a++) != '\0') break; } } } return v; } private uint64_t file_strncmp16(const char *a, const char *b, size_t len, uint32_t flags) { /* * XXX - The 16-bit string compare probably needs to be done * differently, especially if the flags are to be supported. * At the moment, I am unsure. */ flags = 0; return file_strncmp(a, b, len, flags); } private int magiccheck(struct magic_set *ms, struct magic *m) { uint64_t l = m->value.q; uint64_t v; float fl, fv; double dl, dv; int matched; union VALUETYPE *p = &ms->ms_value; switch (m->type) { case FILE_BYTE: v = p->b; break; case FILE_SHORT: case FILE_BESHORT: case FILE_LESHORT: v = p->h; break; case FILE_LONG: case FILE_BELONG: case FILE_LELONG: case FILE_MELONG: case FILE_DATE: case FILE_BEDATE: case FILE_LEDATE: case FILE_MEDATE: case FILE_LDATE: case FILE_BELDATE: case FILE_LELDATE: case FILE_MELDATE: v = p->l; break; case FILE_QUAD: case FILE_LEQUAD: case FILE_BEQUAD: case FILE_QDATE: case FILE_BEQDATE: case FILE_LEQDATE: case FILE_QLDATE: case FILE_BEQLDATE: case FILE_LEQLDATE: v = p->q; break; case FILE_FLOAT: case FILE_BEFLOAT: case FILE_LEFLOAT: fl = m->value.f; fv = p->f; switch (m->reln) { case 'x': matched = 1; break; case '!': matched = fv != fl; break; case '=': matched = fv == fl; break; case '>': matched = fv > fl; break; case '<': matched = fv < fl; break; default: matched = 0; file_magerror(ms, "cannot happen with float: invalid relation `%c'", m->reln); return -1; } return matched; case FILE_DOUBLE: case FILE_BEDOUBLE: case FILE_LEDOUBLE: dl = m->value.d; dv = p->d; switch (m->reln) { case 'x': matched = 1; break; case '!': matched = dv != dl; break; case '=': matched = dv == dl; break; case '>': matched = dv > dl; break; case '<': matched = dv < dl; break; default: matched = 0; file_magerror(ms, "cannot happen with double: invalid relation `%c'", m->reln); return -1; } return matched; case FILE_DEFAULT: l = 0; v = 0; break; case FILE_STRING: case FILE_PSTRING: l = 0; v = file_strncmp(m->value.s, p->s, (size_t)m->vallen, m->str_flags); break; case FILE_BESTRING16: case FILE_LESTRING16: l = 0; v = file_strncmp16(m->value.s, p->s, (size_t)m->vallen, m->str_flags); break; case FILE_SEARCH: { /* search ms->search.s for the string m->value.s */ size_t slen; size_t idx; if (ms->search.s == NULL) return 0; slen = MIN(m->vallen, sizeof(m->value.s)); l = 0; v = 0; for (idx = 0; m->str_range == 0 || idx < m->str_range; idx++) { if (slen + idx > ms->search.s_len) break; v = file_strncmp(m->value.s, ms->search.s + idx, slen, m->str_flags); if (v == 0) { /* found match */ ms->search.offset += idx; break; } } break; } case FILE_REGEX: { int rc; regex_t rx; char errmsg[512]; if (ms->search.s == NULL) return 0; l = 0; rc = regcomp(&rx, m->value.s, REG_EXTENDED|REG_NEWLINE| ((m->str_flags & STRING_IGNORE_CASE) ? REG_ICASE : 0)); if (rc) { (void)regerror(rc, &rx, errmsg, sizeof(errmsg)); file_magerror(ms, "regex error %d, (%s)", rc, errmsg); v = (uint64_t)-1; } else { regmatch_t pmatch[1]; #ifndef REG_STARTEND #define REG_STARTEND 0 size_t l = ms->search.s_len - 1; char c = ms->search.s[l]; ((char *)(intptr_t)ms->search.s)[l] = '\0'; #else pmatch[0].rm_so = 0; pmatch[0].rm_eo = ms->search.s_len; #endif rc = regexec(&rx, (const char *)ms->search.s, 1, pmatch, REG_STARTEND); #if REG_STARTEND == 0 ((char *)(intptr_t)ms->search.s)[l] = c; #endif switch (rc) { case 0: ms->search.s += (int)pmatch[0].rm_so; ms->search.offset += (size_t)pmatch[0].rm_so; ms->search.rm_len = (size_t)(pmatch[0].rm_eo - pmatch[0].rm_so); v = 0; break; case REG_NOMATCH: v = 1; break; default: (void)regerror(rc, &rx, errmsg, sizeof(errmsg)); file_magerror(ms, "regexec error %d, (%s)", rc, errmsg); v = (uint64_t)-1; break; } regfree(&rx); } if (v == (uint64_t)-1) return -1; break; } default: file_magerror(ms, "invalid type %d in magiccheck()", m->type); return -1; } v = file_signextend(ms, m, v); switch (m->reln) { case 'x': if ((ms->flags & MAGIC_DEBUG) != 0) (void) fprintf(stderr, "%llu == *any* = 1\n", (unsigned long long)v); matched = 1; break; case '!': matched = v != l; if ((ms->flags & MAGIC_DEBUG) != 0) (void) fprintf(stderr, "%llu != %llu = %d\n", (unsigned long long)v, (unsigned long long)l, matched); break; case '=': matched = v == l; if ((ms->flags & MAGIC_DEBUG) != 0) (void) fprintf(stderr, "%llu == %llu = %d\n", (unsigned long long)v, (unsigned long long)l, matched); break; case '>': if (m->flag & UNSIGNED) { matched = v > l; if ((ms->flags & MAGIC_DEBUG) != 0) (void) fprintf(stderr, "%llu > %llu = %d\n", (unsigned long long)v, (unsigned long long)l, matched); } else { matched = (int64_t) v > (int64_t) l; if ((ms->flags & MAGIC_DEBUG) != 0) (void) fprintf(stderr, "%lld > %lld = %d\n", (long long)v, (long long)l, matched); } break; case '<': if (m->flag & UNSIGNED) { matched = v < l; if ((ms->flags & MAGIC_DEBUG) != 0) (void) fprintf(stderr, "%llu < %llu = %d\n", (unsigned long long)v, (unsigned long long)l, matched); } else { matched = (int64_t) v < (int64_t) l; if ((ms->flags & MAGIC_DEBUG) != 0) (void) fprintf(stderr, "%lld < %lld = %d\n", (long long)v, (long long)l, matched); } break; case '&': matched = (v & l) == l; if ((ms->flags & MAGIC_DEBUG) != 0) (void) fprintf(stderr, "((%llx & %llx) == %llx) = %d\n", (unsigned long long)v, (unsigned long long)l, (unsigned long long)l, matched); break; case '^': matched = (v & l) != l; if ((ms->flags & MAGIC_DEBUG) != 0) (void) fprintf(stderr, "((%llx & %llx) != %llx) = %d\n", (unsigned long long)v, (unsigned long long)l, (unsigned long long)l, matched); break; default: matched = 0; file_magerror(ms, "cannot happen: invalid relation `%c'", m->reln); return -1; } return matched; } private int print_sep(struct magic_set *ms, int firstline) { if (firstline) return 0; /* * we found another match * put a newline and '-' to do some simple formatting */ return file_printf(ms, "\n- "); }