diff options
Diffstat (limited to 'src/funcs.c')
| -rw-r--r-- | src/funcs.c | 461 |
1 files changed, 461 insertions, 0 deletions
diff --git a/src/funcs.c b/src/funcs.c new file mode 100644 index 0000000..7fc0e5c --- /dev/null +++ b/src/funcs.c @@ -0,0 +1,461 @@ +/* + * Copyright (c) Christos Zoulas 2003. + * All Rights Reserved. + * + * 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. + */ +#include "file.h" + +#ifndef lint +FILE_RCSID("@(#)$File: funcs.c,v 1.61 2012/10/30 23:11:51 christos Exp $") +#endif /* lint */ + +#include "magic.h" +#include <stdarg.h> +#include <stdlib.h> +#include <string.h> +#include <ctype.h> +#if defined(HAVE_WCHAR_H) +#include <wchar.h> +#endif +#if defined(HAVE_WCTYPE_H) +#include <wctype.h> +#endif +#if defined(HAVE_LIMITS_H) +#include <limits.h> +#endif + +#ifndef SIZE_MAX +#define SIZE_MAX ((size_t)~0) +#endif + +/* + * Like printf, only we append to a buffer. + */ +protected int +file_vprintf(struct magic_set *ms, const char *fmt, va_list ap) +{ + int len; + char *buf, *newstr; + + len = vasprintf(&buf, fmt, ap); + if (len < 0) + goto out; + + if (ms->o.buf != NULL) { + len = asprintf(&newstr, "%s%s", ms->o.buf, buf); + free(buf); + if (len < 0) + goto out; + free(ms->o.buf); + buf = newstr; + } + ms->o.buf = buf; + return 0; +out: + file_error(ms, errno, "vasprintf failed"); + return -1; +} + +protected int +file_printf(struct magic_set *ms, const char *fmt, ...) +{ + int rv; + va_list ap; + + va_start(ap, fmt); + rv = file_vprintf(ms, fmt, ap); + va_end(ap); + return rv; +} + +/* + * error - print best error message possible + */ +/*VARARGS*/ +private void +file_error_core(struct magic_set *ms, int error, const char *f, va_list va, + size_t lineno) +{ + /* Only the first error is ok */ + if (ms->event_flags & EVENT_HAD_ERR) + return; + if (lineno != 0) { + free(ms->o.buf); + ms->o.buf = NULL; + file_printf(ms, "line %" SIZE_T_FORMAT "u: ", lineno); + } + file_vprintf(ms, f, va); + if (error > 0) + file_printf(ms, " (%s)", strerror(error)); + ms->event_flags |= EVENT_HAD_ERR; + ms->error = error; +} + +/*VARARGS*/ +protected void +file_error(struct magic_set *ms, int error, const char *f, ...) +{ + va_list va; + va_start(va, f); + file_error_core(ms, error, f, va, 0); + va_end(va); +} + +/* + * Print an error with magic line number. + */ +/*VARARGS*/ +protected void +file_magerror(struct magic_set *ms, const char *f, ...) +{ + va_list va; + va_start(va, f); + file_error_core(ms, 0, f, va, ms->line); + va_end(va); +} + +protected void +file_oomem(struct magic_set *ms, size_t len) +{ + file_error(ms, errno, "cannot allocate %" SIZE_T_FORMAT "u bytes", + len); +} + +protected void +file_badseek(struct magic_set *ms) +{ + file_error(ms, errno, "error seeking"); +} + +protected void +file_badread(struct magic_set *ms) +{ + file_error(ms, errno, "error reading"); +} + +#ifndef COMPILE_ONLY +protected int +file_buffer(struct magic_set *ms, int fd, const char *inname __attribute__ ((unused)), + const void *buf, size_t nb) +{ + int m = 0, rv = 0, looks_text = 0; + int mime = ms->flags & MAGIC_MIME; + const unsigned char *ubuf = CAST(const unsigned char *, buf); + unichar *u8buf = NULL; + size_t ulen; + const char *code = NULL; + const char *code_mime = "binary"; + const char *type = NULL; + + + + if (nb == 0) { + if ((!mime || (mime & MAGIC_MIME_TYPE)) && + file_printf(ms, mime ? "application/x-empty" : + "empty") == -1) + return -1; + return 1; + } else if (nb == 1) { + if ((!mime || (mime & MAGIC_MIME_TYPE)) && + file_printf(ms, mime ? "application/octet-stream" : + "very short file (no magic)") == -1) + return -1; + return 1; + } + + if ((ms->flags & MAGIC_NO_CHECK_ENCODING) == 0) { + looks_text = file_encoding(ms, ubuf, nb, &u8buf, &ulen, + &code, &code_mime, &type); + } + +#ifdef __EMX__ + if ((ms->flags & MAGIC_NO_CHECK_APPTYPE) == 0 && inname) { + switch (file_os2_apptype(ms, inname, buf, nb)) { + case -1: + return -1; + case 0: + break; + default: + return 1; + } + } +#endif +#if HAVE_FORK + /* try compression stuff */ + if ((ms->flags & MAGIC_NO_CHECK_COMPRESS) == 0) + if ((m = file_zmagic(ms, fd, inname, ubuf, nb)) != 0) { + if ((ms->flags & MAGIC_DEBUG) != 0) + (void)fprintf(stderr, "zmagic %d\n", m); + goto done; + } +#endif + /* Check if we have a tar file */ + if ((ms->flags & MAGIC_NO_CHECK_TAR) == 0) + if ((m = file_is_tar(ms, ubuf, nb)) != 0) { + if ((ms->flags & MAGIC_DEBUG) != 0) + (void)fprintf(stderr, "tar %d\n", m); + goto done; + } + + /* Check if we have a CDF file */ + if ((ms->flags & MAGIC_NO_CHECK_CDF) == 0) + if ((m = file_trycdf(ms, fd, ubuf, nb)) != 0) { + if ((ms->flags & MAGIC_DEBUG) != 0) + (void)fprintf(stderr, "cdf %d\n", m); + goto done; + } + + /* try soft magic tests */ + if ((ms->flags & MAGIC_NO_CHECK_SOFT) == 0) + if ((m = file_softmagic(ms, ubuf, nb, BINTEST, + looks_text)) != 0) { + if ((ms->flags & MAGIC_DEBUG) != 0) + (void)fprintf(stderr, "softmagic %d\n", m); +#ifdef BUILTIN_ELF + if ((ms->flags & MAGIC_NO_CHECK_ELF) == 0 && m == 1 && + nb > 5 && fd != -1) { + /* + * We matched something in the file, so this + * *might* be an ELF file, and the file is at + * least 5 bytes long, so if it's an ELF file + * it has at least one byte past the ELF magic + * number - try extracting information from the + * ELF headers that cannot easily * be + * extracted with rules in the magic file. + */ + if ((m = file_tryelf(ms, fd, ubuf, nb)) != 0) + if ((ms->flags & MAGIC_DEBUG) != 0) + (void)fprintf(stderr, + "elf %d\n", m); + } +#endif + goto done; + } + + /* try text properties */ + if ((ms->flags & MAGIC_NO_CHECK_TEXT) == 0) { + + if ((m = file_ascmagic(ms, ubuf, nb, looks_text)) != 0) { + if ((ms->flags & MAGIC_DEBUG) != 0) + (void)fprintf(stderr, "ascmagic %d\n", m); + goto done; + } + + /* try to discover text encoding */ + if ((ms->flags & MAGIC_NO_CHECK_ENCODING) == 0) { + if (looks_text == 0) + if ((m = file_ascmagic_with_encoding( ms, ubuf, + nb, u8buf, ulen, code, type, looks_text)) + != 0) { + if ((ms->flags & MAGIC_DEBUG) != 0) + (void)fprintf(stderr, + "ascmagic/enc %d\n", m); + goto done; + } + } + } + + /* give up */ + m = 1; + if ((!mime || (mime & MAGIC_MIME_TYPE)) && + file_printf(ms, mime ? "application/octet-stream" : "data") == -1) { + rv = -1; + } + done: + if ((ms->flags & MAGIC_MIME_ENCODING) != 0) { + if (ms->flags & MAGIC_MIME_TYPE) + if (file_printf(ms, "; charset=") == -1) + rv = -1; + if (file_printf(ms, "%s", code_mime) == -1) + rv = -1; + } + free(u8buf); + if (rv) + return rv; + + return m; +} +#endif + +protected int +file_reset(struct magic_set *ms) +{ + if (ms->mlist[0] == NULL) { + file_error(ms, 0, "no magic files loaded"); + return -1; + } + if (ms->o.buf) { + free(ms->o.buf); + ms->o.buf = NULL; + } + if (ms->o.pbuf) { + free(ms->o.pbuf); + ms->o.pbuf = NULL; + } + ms->event_flags &= ~EVENT_HAD_ERR; + ms->error = -1; + return 0; +} + +#define OCTALIFY(n, o) \ + /*LINTED*/ \ + (void)(*(n)++ = '\\', \ + *(n)++ = (((uint32_t)*(o) >> 6) & 3) + '0', \ + *(n)++ = (((uint32_t)*(o) >> 3) & 7) + '0', \ + *(n)++ = (((uint32_t)*(o) >> 0) & 7) + '0', \ + (o)++) + +protected const char * +file_getbuffer(struct magic_set *ms) +{ + char *pbuf, *op, *np; + size_t psize, len; + + if (ms->event_flags & EVENT_HAD_ERR) + return NULL; + + if (ms->flags & MAGIC_RAW) + return ms->o.buf; + + if (ms->o.buf == NULL) + return NULL; + + /* * 4 is for octal representation, + 1 is for NUL */ + len = strlen(ms->o.buf); + if (len > (SIZE_MAX - 1) / 4) { + file_oomem(ms, len); + return NULL; + } + psize = len * 4 + 1; + if ((pbuf = CAST(char *, realloc(ms->o.pbuf, psize))) == NULL) { + file_oomem(ms, psize); + return NULL; + } + ms->o.pbuf = pbuf; + +#if defined(HAVE_WCHAR_H) && defined(HAVE_MBRTOWC) && defined(HAVE_WCWIDTH) + { + mbstate_t state; + wchar_t nextchar; + int mb_conv = 1; + size_t bytesconsumed; + char *eop; + (void)memset(&state, 0, sizeof(mbstate_t)); + + np = ms->o.pbuf; + op = ms->o.buf; + eop = op + len; + + while (op < eop) { + bytesconsumed = mbrtowc(&nextchar, op, + (size_t)(eop - op), &state); + if (bytesconsumed == (size_t)(-1) || + bytesconsumed == (size_t)(-2)) { + mb_conv = 0; + break; + } + + if (iswprint(nextchar)) { + (void)memcpy(np, op, bytesconsumed); + op += bytesconsumed; + np += bytesconsumed; + } else { + while (bytesconsumed-- > 0) + OCTALIFY(np, op); + } + } + *np = '\0'; + + /* Parsing succeeded as a multi-byte sequence */ + if (mb_conv != 0) + return ms->o.pbuf; + } +#endif + + for (np = ms->o.pbuf, op = ms->o.buf; *op;) { + if (isprint((unsigned char)*op)) { + *np++ = *op++; + } else { + OCTALIFY(np, op); + } + } + *np = '\0'; + return ms->o.pbuf; +} + +protected int +file_check_mem(struct magic_set *ms, unsigned int level) +{ + size_t len; + + if (level >= ms->c.len) { + len = (ms->c.len += 20) * sizeof(*ms->c.li); + ms->c.li = CAST(struct level_info *, (ms->c.li == NULL) ? + malloc(len) : + realloc(ms->c.li, len)); + if (ms->c.li == NULL) { + file_oomem(ms, len); + return -1; + } + } + ms->c.li[level].got_match = 0; +#ifdef ENABLE_CONDITIONALS + ms->c.li[level].last_match = 0; + ms->c.li[level].last_cond = COND_NONE; +#endif /* ENABLE_CONDITIONALS */ + return 0; +} + +protected size_t +file_printedlen(const struct magic_set *ms) +{ + return ms->o.buf == NULL ? 0 : strlen(ms->o.buf); +} + +protected int +file_replace(struct magic_set *ms, const char *pat, const char *rep) +{ + regex_t rx; + int rc; + + rc = regcomp(&rx, pat, REG_EXTENDED); + if (rc) { + char errmsg[512]; + (void)regerror(rc, &rx, errmsg, sizeof(errmsg)); + file_magerror(ms, "regex error %d, (%s)", rc, errmsg); + return -1; + } else { + regmatch_t rm; + int nm = 0; + while (regexec(&rx, ms->o.buf, 1, &rm, 0) == 0) { + ms->o.buf[rm.rm_so] = '\0'; + if (file_printf(ms, "%s%s", rep, + rm.rm_eo != 0 ? ms->o.buf + rm.rm_eo : "") == -1) + return -1; + nm++; + } + regfree(&rx); + return nm; + } +} |