dos.c

linux下自动mount各种即插即用设备的一个小程序源码 文件包含内容： /vold.h /vold.c /split.h /split.c /disktype-6/disktype.c

/*
 * dos.c
 * Detection of DOS parition maps and file systems
 *
 * Copyright (c) 2003 Christoph Pfisterer
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use, copy,
 * modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE. 
 */

#include "detect.h"

/*
 * DOS partition types
 *
 * Taken from fdisk/i386_sys_types.c and fdisk/common.h of
 * util-linux 2.11n (as packaged by Debian), Feb 08, 2003.
 */

struct systypes {
	unsigned char type;
	char *name;
};

struct systypes i386_sys_types[] = {
	                                   { 0x00, "Empty" },
	                                   { 0x01, "FAT12" },
	                                   { 0x02, "XENIX root" },
	                                   { 0x03, "XENIX usr" },
	                                   { 0x04, "FAT16 <32M" },
	                                   { 0x05, "Extended" },
	                                   { 0x06, "FAT16" },
	                                   { 0x07, "HPFS/NTFS" },
	                                   { 0x08, "AIX" },
	                                   { 0x09, "AIX bootable" },
	                                   { 0x0a, "OS/2 Boot Manager" },
	                                   { 0x0b, "Win95 FAT32" },
	                                   { 0x0c, "Win95 FAT32 (LBA)" },
	                                   { 0x0e, "Win95 FAT16 (LBA)" },
	                                   { 0x0f, "Win95 Ext'd (LBA)" },
	                                   { 0x10, "OPUS" },
	                                   { 0x11, "Hidden FAT12" },
	                                   { 0x12, "Compaq diagnostics" },
	                                   { 0x14, "Hidden FAT16 <32M" },
	                                   { 0x16, "Hidden FAT16" },
	                                   { 0x17, "Hidden HPFS/NTFS" },
	                                   { 0x18, "AST SmartSleep" },
	                                   { 0x1b, "Hidden Win95 FAT32" },
	                                   { 0x1c, "Hidden Win95 FAT32 (LBA)" },
	                                   { 0x1e, "Hidden Win95 FAT16 (LBA)" },
	                                   { 0x24, "NEC DOS" },
	                                   { 0x39, "Plan 9" },
	                                   { 0x3c, "PartitionMagic recovery" },
	                                   { 0x40, "Venix 80286" },
	                                   { 0x41, "PPC PReP Boot" },
	                                   { 0x42, "SFS" },
	                                   { 0x4d, "QNX4.x" },
	                                   { 0x4e, "QNX4.x 2nd part" },
	                                   { 0x4f, "QNX4.x 3rd part" },
	                                   { 0x50, "OnTrack DM" },
	                                   { 0x51, "OnTrack DM6 Aux1" },
	                                   { 0x52, "CP/M" },
	                                   { 0x53, "OnTrack DM6 Aux3" },
	                                   { 0x54, "OnTrackDM6" },
	                                   { 0x55, "EZ-Drive" },
	                                   { 0x56, "Golden Bow" },
	                                   { 0x5c, "Priam Edisk" },
	                                   { 0x61, "SpeedStor" },
	                                   { 0x63, "GNU HURD or SysV" },
	                                   { 0x64, "Novell Netware 286" },
	                                   { 0x65, "Novell Netware 386" },
	                                   { 0x70, "DiskSecure Multi-Boot" },
	                                   { 0x75, "PC/IX" },
	                                   { 0x78, "XOSL" },
	                                   { 0x80, "Old Minix" },
	                                   { 0x81, "Minix / old Linux" },
	                                   { 0x82, "Linux swap / Solaris" },
	                                   { 0x83, "Linux" },
	                                   { 0x84, "OS/2 hidden C: drive" },
	                                   { 0x85, "Linux extended" },
	                                   { 0x86, "NTFS volume set" },
	                                   { 0x87, "NTFS volume set" },
	                                   { 0x8e, "Linux LVM" },
	                                   { 0x93, "Amoeba" },
	                                   { 0x94, "Amoeba BBT" },
	                                   { 0x9f, "BSD/OS" },
	                                   { 0xa0, "IBM Thinkpad hibernation" },
	                                   { 0xa5, "FreeBSD" },
	                                   { 0xa6, "OpenBSD" },
	                                   { 0xa7, "NeXTSTEP" },
	                                   { 0xa9, "NetBSD" },
	                                   { 0xb7, "BSDI fs" },
	                                   { 0xb8, "BSDI swap" },
	                                   { 0xbb, "Boot Wizard hidden" },
	                                   { 0xc1, "DRDOS/sec (FAT-12)" },
	                                   { 0xc4, "DRDOS/sec (FAT-16 < 32M)" },
	                                   { 0xc6, "DRDOS/sec (FAT-16)" },
	                                   { 0xc7, "Syrinx" },
	                                   { 0xda, "Non-FS data" },
	                                   { 0xdb, "CP/M / CTOS / ..." },
	                                   { 0xde, "Dell Utility" },
	                                   { 0xdf, "BootIt" },
	                                   { 0xe1, "DOS access" },
	                                   { 0xe3, "DOS R/O" },
	                                   { 0xe4, "SpeedStor" },
	                                   { 0xeb, "BeOS fs" },
	                                   { 0xee, "EFI GPT" },
	                                   { 0xef, "EFI (FAT-12/16/32)" },
	                                   { 0xf0, "Linux/PA-RISC boot" },
	                                   { 0xf1, "SpeedStor" },
	                                   { 0xf4, "SpeedStor" },
	                                   { 0xf2, "DOS secondary" },
	                                   { 0xfd, "Linux raid autodetect" },
	                                   { 0xfe, "LANstep" },
	                                   { 0xff, "BBT" },
	                                   { 0, 0 }
                                   };


static char * get_name_for_type(int type) {
	int i;

	for (i = 0; i386_sys_types[i].name; i++)
		if (i386_sys_types[i].type == type)
			return i386_sys_types[i].name;
	return _T("Unknown");
}

/*
 * DOS-style partition map / MBR
 */

int detect_dos_partmap(SECTION *section, DT_Info* info) {
	unsigned char *buf;
	int i, off, used, type, types[4], bootflags[4];
	U32 start, size, starts[4], sizes[4];
	int extpartnum = 5;
	SECTION rs;
	/* char s[256], append[64]; */

	/* partition maps only occur at the start of a device */
	if (section->pos != 0)
		return DT_NO;

	if (get_buffer(section, 0, 512, (void **)&buf) < 512)
		return DT_NO;

	/* check signature */
	if (buf[510] != 0x55 || buf[511] != 0xAA)
		return DT_NO;

	/* get entries and check */
	used = 0;
	for (off = 446, i = 0; i < 4; i++, off += 16) {
		/* get data */
		bootflags[i] = buf[off];
		types[i] = buf[off + 4];
		starts[i] = get_le_long(buf + off + 8);
		sizes[i] = get_le_long(buf + off + 12);

		/* bootable flag: either on or off */
		if (bootflags[i] != 0x00 && bootflags[i] != 0x80)
			return DT_NO;
		/* size non-zero -> entry in use */
		if (starts[i] && sizes[i])
			used = 1;
	}
	if (!used)
		return DT_NO;


	DBG("Is DOS Partition. * NOT implemented* returning DT_NO");
	return DT_NO;
	
	/* parse the data for real */
	/* print_line(level, "DOS partition map"); */
	for (i = 0; i < 4; i++) {
		start = starts[i];
		size = sizes[i];
		type = types[i];
		if (start == 0 || size == 0)
			continue;

		/* sprintf(append, " from %lu", start);
		if (bootflags[i] == 0x80)
		  strcat(append, ", bootable"); */

		info->partmap.type = DT_DOS_PARTMAP;
		info->partmap.part_type = type;
		info->partmap.part_type_name = get_name_for_type(type);
		info->partmap.bootable = (bootflags[i] == 0x80);
		info->partmap.start = start;
		info->partmap.size = size * 512;
		/*format_blocky_size(s, size, 512, "sectors", append);
		print_line(level, "Partition %d: %s",
		    i+1, s);

		print_line(level + 1, "Type 0x%02X (%s)", type, get_name_for_type(type)); */

		info->next = new_DT_Info();
		if (type == 0x05 || type == 0x0f || type == 0x85) {
			/* extended partition - shortcut :-) */
			detect_dos_partmap_ext(section, start, info->next, &extpartnum);
		} else {
			/* recurse for content detection */
			rs.source = section->source;
			rs.pos = section->pos + (U64)start * 512;
			rs.size = (U64)size * 512;
			rs.flags = 0;
			info->next = dt_detect(&rs);
		}
	}
	
	if(info->partmap.type == DT_DOS_PARTMAP)
		return DT_YES;

	return DT_NO;
}

int detect_dos_partmap_ext(SECTION *section, U64 extbase, DT_Info* info, int *extpartnum) {
	unsigned char *buf;
	U64 tablebase, nexttablebase;
	int i, off, type, types[4];
	U32 start, size, starts[4], sizes[4];
	SECTION rs;
	/* char s[256], append[64]; */

	for (tablebase = extbase; tablebase; tablebase = nexttablebase) {
		/* read sector from linked list */
		if (get_buffer(section, tablebase << 9, 512, (void **)&buf) < 512)
			return DT_NO;

		/* check signature */
		if (buf[510] != 0x55 || buf[511] != 0xAA) {
			info->partmap.type = DT_DOS_PARTMAP;
			info->partmap.part_type_name = _T("Signature missing");
			/* print_line(level, "Signature missing"); */
			
			/* return yes or no?? unsure */
			return DT_NO;
		}

		/* get entries */
		for (off = 446, i = 0; i < 4; i++, off += 16) {
			types[i] = buf[off + 4];
			starts[i] = get_le_long(buf + off + 8);
			sizes[i] = get_le_long(buf + off + 12);