1212793Sdim/*- 2212793Sdim * Copyright (c) 2004 Pawel Jakub Dawidek <pjd@FreeBSD.org> 3212793Sdim * Copyright (c) 2006 Tobias Reifenberger 4212793Sdim * All rights reserved. 5212793Sdim * 6212793Sdim * Redistribution and use in source and binary forms, with or without 7212793Sdim * modification, are permitted provided that the following conditions 8212793Sdim * are met: 9212793Sdim * 1. Redistributions of source code must retain the above copyright 10212793Sdim * notice, this list of conditions and the following disclaimer. 11212793Sdim * 2. Redistributions in binary form must reproduce the above copyright 12212793Sdim * notice, this list of conditions and the following disclaimer in the 13212793Sdim * documentation and/or other materials provided with the distribution. 14212793Sdim * 15212793Sdim * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 16212793Sdim * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17212793Sdim * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18218893Sdim * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 19249423Sdim * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20249423Sdim * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21212793Sdim * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22226633Sdim * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23212793Sdim * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24212793Sdim * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25212793Sdim * SUCH DAMAGE. 26212793Sdim */ 27212793Sdim 28249423Sdim#include <sys/cdefs.h> 29218893Sdim__FBSDID("$FreeBSD$"); 30249423Sdim 31212793Sdim#include <sys/param.h> 32249423Sdim#include <sys/systm.h> 33249423Sdim#include <sys/kernel.h> 34249423Sdim#include <sys/malloc.h> 35249423Sdim 36249423Sdim#include <geom/geom.h> 37249423Sdim#include <geom/label/g_label.h> 38249423Sdim#include <geom/label/g_label_msdosfs.h> 39249423Sdim 40212793Sdim#define G_LABEL_MSDOSFS_DIR "msdosfs" 41212793Sdim#define LABEL_NO_NAME "NO NAME " 42212793Sdim 43212793Sdimstatic void 44212793Sdimg_label_msdosfs_taste(struct g_consumer *cp, char *label, size_t size) 45212793Sdim{ 46212793Sdim struct g_provider *pp; 47212793Sdim FAT_BSBPB *pfat_bsbpb; 48212793Sdim FAT32_BSBPB *pfat32_bsbpb; 49212793Sdim FAT_DES *pfat_entry; 50218893Sdim uint8_t *sector0, *sector; 51218893Sdim uint32_t i; 52212793Sdim 53212793Sdim g_topology_assert_not(); 54218893Sdim pp = cp->provider; 55218893Sdim sector0 = NULL; 56218893Sdim sector = NULL; 57218893Sdim bzero(label, size); 58218893Sdim 59218893Sdim /* Check if the sector size of the medium is a valid FAT sector size. */ 60218893Sdim switch(pp->sectorsize) { 61218893Sdim case 512: 62218893Sdim case 1024: 63218893Sdim case 2048: 64218893Sdim case 4096: 65218893Sdim break; 66218893Sdim default: 67218893Sdim G_LABEL_DEBUG(1, "MSDOSFS: %s: sector size %d not compatible.", 68218893Sdim pp->name, pp->sectorsize); 69218893Sdim return; 70223017Sdim } 71218893Sdim 72218893Sdim /* Load 1st sector with boot sector and boot parameter block. */ 73218893Sdim sector0 = (uint8_t *)g_read_data(cp, 0, pp->sectorsize, NULL); 74218893Sdim if (sector0 == NULL) 75212793Sdim return; 76212793Sdim 77212793Sdim /* Check for the FAT boot sector signature. */ 78212793Sdim if (sector0[510] != 0x55 || sector0[511] != 0xaa) { 79212793Sdim G_LABEL_DEBUG(1, "MSDOSFS: %s: no FAT signature found.", 80212793Sdim pp->name); 81212793Sdim goto error; 82212793Sdim } 83218893Sdim 84212793Sdim 85218893Sdim /* 86234353Sdim * Test if this is really a FAT volume and determine the FAT type. 87218893Sdim */ 88212793Sdim 89212793Sdim pfat_bsbpb = (FAT_BSBPB *)sector0; 90239462Sdim pfat32_bsbpb = (FAT32_BSBPB *)sector0; 91239462Sdim 92239462Sdim if (UINT16BYTES(pfat_bsbpb->BPB_FATSz16) != 0) { 93212793Sdim /* 94212793Sdim * If the BPB_FATSz16 field is not zero and the string "FAT" is 95212793Sdim * at the right place, this should be a FAT12 or FAT16 volume. 96212793Sdim */ 97212793Sdim if (strncmp(pfat_bsbpb->BS_FilSysType, "FAT", 3) != 0) { 98234353Sdim G_LABEL_DEBUG(1, 99218893Sdim "MSDOSFS: %s: FAT12/16 volume not valid.", 100212793Sdim pp->name); 101212793Sdim goto error; 102212793Sdim } 103243830Sdim G_LABEL_DEBUG(1, "MSDOSFS: %s: FAT12/FAT16 volume detected.", 104243830Sdim pp->name); 105243830Sdim 106243830Sdim /* A volume with no name should have "NO NAME " as label. */ 107243830Sdim if (strncmp(pfat_bsbpb->BS_VolLab, LABEL_NO_NAME, 108243830Sdim sizeof(pfat_bsbpb->BS_VolLab)) == 0) { 109243830Sdim G_LABEL_DEBUG(1, 110243830Sdim "MSDOSFS: %s: FAT12/16 volume has no name.", 111243830Sdim pp->name); 112243830Sdim goto error; 113243830Sdim } 114243830Sdim strlcpy(label, pfat_bsbpb->BS_VolLab, 115243830Sdim MIN(size, sizeof(pfat_bsbpb->BS_VolLab) + 1)); 116243830Sdim } else if (UINT32BYTES(pfat32_bsbpb->BPB_FATSz32) != 0) { 117243830Sdim uint32_t fat_FirstDataSector, fat_BytesPerSector, offset; 118243830Sdim 119243830Sdim /* 120243830Sdim * If the BPB_FATSz32 field is not zero and the string "FAT" is 121243830Sdim * at the right place, this should be a FAT32 volume. 122243830Sdim */ 123243830Sdim if (strncmp(pfat32_bsbpb->BS_FilSysType, "FAT", 3) != 0) { 124243830Sdim G_LABEL_DEBUG(1, "MSDOSFS: %s: FAT32 volume not valid.", 125243830Sdim pp->name); 126243830Sdim goto error; 127243830Sdim } 128243830Sdim G_LABEL_DEBUG(1, "MSDOSFS: %s: FAT32 volume detected.", 129243830Sdim pp->name); 130243830Sdim 131243830Sdim /* 132243830Sdim * If the volume label is not "NO NAME " we're done. 133243830Sdim */ 134243830Sdim if (strncmp(pfat32_bsbpb->BS_VolLab, LABEL_NO_NAME, 135243830Sdim sizeof(pfat32_bsbpb->BS_VolLab)) != 0) { 136243830Sdim strlcpy(label, pfat32_bsbpb->BS_VolLab, 137221345Sdim MIN(size, sizeof(pfat32_bsbpb->BS_VolLab) + 1)); 138243830Sdim goto endofchecks; 139243830Sdim } 140243830Sdim 141218893Sdim /* 142212793Sdim * If the volume label "NO NAME " is in the boot sector, the 143243830Sdim * label of FAT32 volumes may be stored as a special entry in 144212793Sdim * the root directory. 145212793Sdim */ 146218893Sdim fat_FirstDataSector = 147251662Sdim UINT16BYTES(pfat32_bsbpb->BPB_RsvdSecCnt) + 148251662Sdim (pfat32_bsbpb->BPB_NumFATs * 149249423Sdim UINT32BYTES(pfat32_bsbpb->BPB_FATSz32)); 150243830Sdim fat_BytesPerSector = UINT16BYTES(pfat32_bsbpb->BPB_BytsPerSec); 151212793Sdim 152218893Sdim G_LABEL_DEBUG(2, 153212793Sdim "MSDOSFS: FAT_FirstDataSector=0x%x, FAT_BytesPerSector=%d", 154218893Sdim fat_FirstDataSector, fat_BytesPerSector); 155218893Sdim 156218893Sdim for (offset = fat_BytesPerSector * fat_FirstDataSector;; 157218893Sdim offset += fat_BytesPerSector) { 158234353Sdim sector = (uint8_t *)g_read_data(cp, offset, 159218893Sdim fat_BytesPerSector, NULL); 160218893Sdim if (sector == NULL) 161218893Sdim goto error; 162234353Sdim 163234353Sdim pfat_entry = (FAT_DES *)sector; 164234353Sdim do { 165234353Sdim /* No more entries available. */ 166234353Sdim if (pfat_entry->DIR_Name[0] == 0) { 167234353Sdim G_LABEL_DEBUG(1, "MSDOSFS: %s: " 168234353Sdim "FAT32 volume has no name.", 169234353Sdim pp->name); 170218893Sdim goto error; 171218893Sdim } 172234353Sdim 173234353Sdim /* Skip empty or long name entries. */ 174239462Sdim if (pfat_entry->DIR_Name[0] == 0xe5 || 175212793Sdim (pfat_entry->DIR_Attr & 176212793Sdim FAT_DES_ATTR_LONG_NAME) == 177212793Sdim FAT_DES_ATTR_LONG_NAME) { 178226633Sdim continue; 179226633Sdim } 180234353Sdim 181234353Sdim /* 182249423Sdim * The name of the entry is the volume label if 183234353Sdim * ATTR_VOLUME_ID is set. 184234353Sdim */ 185249423Sdim if (pfat_entry->DIR_Attr & 186234353Sdim FAT_DES_ATTR_VOLUME_ID) { 187218893Sdim strlcpy(label, pfat_entry->DIR_Name, 188249423Sdim MIN(size, 189234353Sdim sizeof(pfat_entry->DIR_Name) + 1)); 190249423Sdim goto endofchecks; 191249423Sdim } 192249423Sdim } while((uint8_t *)(++pfat_entry) < 193249423Sdim (uint8_t *)(sector + fat_BytesPerSector)); 194249423Sdim g_free(sector); 195249423Sdim } 196249423Sdim } else { 197249423Sdim G_LABEL_DEBUG(1, "MSDOSFS: %s: no FAT volume detected.", 198239462Sdim pp->name); 199249423Sdim goto error; 200218893Sdim } 201218893Sdim 202218893Sdimendofchecks: 203239462Sdim for (i = size - 1; i > 0; i--) { 204239462Sdim if (label[i] == '\0') 205239462Sdim continue; 206218893Sdim else if (label[i] == ' ') 207218893Sdim label[i] = '\0'; 208218893Sdim else 209218893Sdim break; 210218893Sdim } 211218893Sdim 212239462Sdimerror: 213239462Sdim if (sector0 != NULL) 214239462Sdim g_free(sector0); 215218893Sdim if (sector != NULL) 216218893Sdim g_free(sector); 217239462Sdim} 218218893Sdim 219218893Sdimstruct g_label_desc g_label_msdosfs = { 220218893Sdim .ld_taste = g_label_msdosfs_taste, 221218893Sdim .ld_dir = G_LABEL_MSDOSFS_DIR, 222221345Sdim .ld_enabled = 1 223212793Sdim}; 224212793Sdim 225249423SdimG_LABEL_INIT(msdosfs, g_label_msdosfs, "Create device nodes for MSDOSFS volumes"); 226223017Sdim