fsmagic.c

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/*
 * 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.
 */
/*
 * fsmagic - magic based on filesystem info - directory, special files, etc.
 */
 
#include "file.h"
 
#ifndef lint
FILE_RCSID("@(#)$File: fsmagic.c,v 1.85 2022/12/26 17:31:14 christos Exp $")
#endif  /* lint */
 
#include "magic.h"
#include <string.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <stdlib.h>
/* Since major is a function on SVR4, we cannot use `ifndef major'.  */
#ifdef MAJOR_IN_MKDEV
# include <sys/mkdev.h>
# define HAVE_MAJOR
#endif
#ifdef HAVE_SYS_SYSMACROS_H
# include <sys/sysmacros.h>
#endif
#ifdef MAJOR_IN_SYSMACROS
# define HAVE_MAJOR
#endif
#if defined(major) && !defined(HAVE_MAJOR)
/* Might be defined in sys/types.h.  */
# define HAVE_MAJOR
#endif
#ifdef WIN32
# define WIN32_LEAN_AND_MEAN
# include <windows.h>
#endif
 
#ifndef HAVE_MAJOR
# define major(dev)  (((dev) >> 8) & 0xff)
# define minor(dev)  ((dev) & 0xff)
#endif
#undef HAVE_MAJOR
 
#ifdef PHP_WIN32
 
# undef S_IFIFO
#endif
file_private int
handle_mime(struct magic_set *ms, int mime, const char *str)
{
    if ((mime & MAGIC_MIME_TYPE)) {
        if (file_printf(ms, "inode/%s", str) == -1)
            return -1;
        if ((mime & MAGIC_MIME_ENCODING) && file_printf(ms,
            "; charset=") == -1)
            return -1;
    }
    if ((mime & MAGIC_MIME_ENCODING) && file_printf(ms, "binary") == -1)
        return -1;
    return 0;
}
 
file_protected int
file_fsmagic(struct magic_set *ms, const char *fn, zend_stat_t *sb)
{
    int ret, did = 0;
    int mime = ms->flags & MAGIC_MIME;
    int silent = ms->flags & (MAGIC_APPLE|MAGIC_EXTENSION);
 
    if (fn == NULL)
        return 0;
 
#define COMMA   (did++ ? ", " : "")
    ret = php_sys_stat(fn, sb);
 
    if (ret) {
        if (ms->flags & MAGIC_ERROR) {
            file_error(ms, errno, "cannot stat `%s'", fn);
            return -1;
        }
        if (file_printf(ms, "cannot open `%s' (%s)",
            fn, strerror(errno)) == -1)
            return -1;
        return 0;
    }
 
    ret = 1;
    if (!mime && !silent) {
#ifdef S_ISUID
        if (sb->st_mode & S_ISUID)
            if (file_printf(ms, "%ssetuid", COMMA) == -1)
                return -1;
#endif
#ifdef S_ISGID
        if (sb->st_mode & S_ISGID)
            if (file_printf(ms, "%ssetgid", COMMA) == -1)
                return -1;
#endif
#ifdef S_ISVTX
        if (sb->st_mode & S_ISVTX)
            if (file_printf(ms, "%ssticky", COMMA) == -1)
                return -1;
#endif
    }
 
    switch (sb->st_mode & S_IFMT) {
#ifndef PHP_WIN32
# ifdef S_IFCHR
        case S_IFCHR:
            /*
             * If -s has been specified, treat character special files
             * like ordinary files.  Otherwise, just report that they
             * are block special files and go on to the next file.
             */
            if ((ms->flags & MAGIC_DEVICES) != 0) {
                ret = 0;
                break;
            }
            if (mime) {
                if (handle_mime(ms, mime, "chardevice") == -1)
                    return -1;
            } else {
#  ifdef HAVE_STAT_ST_RDEV
#   ifdef dv_unit
            if (file_printf(ms, "%scharacter special (%d/%d/%d)",
                COMMA, major(sb->st_rdev), dv_unit(sb->st_rdev),
                    dv_subunit(sb->st_rdev)) == -1)
                return -1;
# else
            if (file_printf(ms, "%scharacter special (%ld/%ld)",
                COMMA, (long)major(sb->st_rdev),
                (long)minor(sb->st_rdev)) == -1)
                return -1;
# endif
#else
            if (file_printf(ms, "%scharacter special", COMMA) == -1)
                return -1;
#endif
    }
            return 1;
# endif
#endif
 
#ifdef  S_IFIFO
    case S_IFIFO:
        if((ms->flags & MAGIC_DEVICES) != 0)
            break;
        if (mime) {
            if (handle_mime(ms, mime, "fifo") == -1)
                return -1;
        } else if (silent) {
        } else if (file_printf(ms, "%sfifo (named pipe)", COMMA) == -1)
            return -1;
        break;
#endif
#ifdef  S_IFDOOR
    case S_IFDOOR:
        if (mime) {
            if (handle_mime(ms, mime, "door") == -1)
                return -1;
        } else if (silent) {
        } else if (file_printf(ms, "%sdoor", COMMA) == -1)
            return -1;
        break;
#endif
#ifdef  S_IFLNK
    case S_IFLNK:
        /* stat is used, if it made here then the link is broken */
            if (ms->flags & MAGIC_ERROR) {
                file_error(ms, errno, "unreadable symlink `%s'", fn);
                return -1;
            }
    return 1;
#endif
 
#ifdef  S_IFSOCK
#ifndef __COHERENT__
    case S_IFSOCK:
        if (mime) {
            if (handle_mime(ms, mime, "socket") == -1)
                return -1;
        } else if (silent) {
        } else if (file_printf(ms, "%ssocket", COMMA) == -1)
            return -1;
        break;
#endif
#endif
    case S_IFREG:
        /*
         * regular file, check next possibility
         *
         * If stat() tells us the file has zero length, report here that
         * the file is empty, so we can skip all the work of opening and
         * reading the file.
         * But if the -s option has been given, we skip this
         * optimization, since on some systems, stat() reports zero
         * size for raw disk partitions. (If the block special device
         * really has zero length, the fact that it is empty will be
         * detected and reported correctly when we read the file.)
         */
        if ((ms->flags & MAGIC_DEVICES) == 0 && sb->st_size == 0) {
            if (mime) {
                if (handle_mime(ms, mime, "x-empty") == -1)
                    return -1;
            } else if (silent) {
            } else if (file_printf(ms, "%sempty", COMMA) == -1)
                return -1;
            break;
        }
        ret = 0;
        break;
 
    default:
        file_error(ms, 0, "invalid mode 0%o", sb->st_mode);
        return -1;
        /*NOTREACHED*/
    }
 
    if (!silent && !mime && did && ret == 0) {
        if (file_printf(ms, " ") == -1)
            return -1;
    }
    /*
     * If we were looking for extensions or apple (silent) it is not our
     * job to print here, so don't count this as a match.
     */
    if (ret == 1 && silent)
        return 0;
    return ret;
}