1 | ␊ |
2 | /*␊ |
3 | * Copyright (c) 2004 Apple Computer, Inc. All rights reserved.␊ |
4 | *␊ |
5 | * @APPLE_LICENSE_HEADER_START@␊ |
6 | * ␊ |
7 | * Copyright (c) 1999-2004 Apple Computer, Inc. All Rights Reserved.␊ |
8 | * ␊ |
9 | * This file contains Original Code and/or Modifications of Original Code␊ |
10 | * as defined in and that are subject to the Apple Public Source License␊ |
11 | * Version 2.0 (the 'License'). You may not use this file except in␊ |
12 | * compliance with the License. Please obtain a copy of the License at␊ |
13 | * http://www.opensource.apple.com/apsl/ and read it before using this␊ |
14 | * file.␊ |
15 | * ␊ |
16 | * The Original Code and all software distributed under the License are␊ |
17 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER␊ |
18 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,␊ |
19 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,␊ |
20 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.␊ |
21 | * Please see the License for the specific language governing rights and␊ |
22 | * limitations under the License.␊ |
23 | * ␊ |
24 | * @APPLE_LICENSE_HEADER_END@␊ |
25 | */␊ |
26 | /*␊ |
27 | * dmazar, 14/7/2011␊ |
28 | * support for EXFAT volume label reading␊ |
29 | * EXFAT info from: http://www.ntfs.com/exfat-overview.htm␊ |
30 | *␊ |
31 | * EXFAT shares partition type with NTFS (0x7) and easiest way of␊ |
32 | * adding it was through ntfs.c module. All functions here are called␊ |
33 | * from similar ntfs.c funcs as fallback (if not NTFS, maybe it's EXFAT).␊ |
34 | */␊ |
35 | ␊ |
36 | #include "libsaio.h"␊ |
37 | #include "sl.h"␊ |
38 | ␊ |
39 | #ifndef DEBUG_EXFAT␊ |
40 | #define DEBUG_EXFAT 0␊ |
41 | #endif␊ |
42 | ␊ |
43 | #if DEBUG_EXFAT␊ |
44 | #define DBG(x...)␉␉printf(x)␊ |
45 | #define PAUSE()␉␉␉getc()␊ |
46 | #else␊ |
47 | #define DBG(x...)␊ |
48 | #define PAUSE()␊ |
49 | #endif␊ |
50 | ␊ |
51 | #define␉EXFAT_BBID␉"EXFAT "␊ |
52 | #define␉EXFAT_BBIDLEN␉8␊ |
53 | ␊ |
54 | #define MAX_BLOCK_SIZE␉␉4096␊ |
55 | #define MAX_CLUSTER_SIZE␉32 * 1024 * 1024␊ |
56 | ␊ |
57 | #define ERROR -1␊ |
58 | ␊ |
59 | ␊ |
60 | /*␊ |
61 | * boot sector of the partition␊ |
62 | * http://www.ntfs.com/exfat-boot-sector.htm␊ |
63 | */␊ |
64 | struct exfatbootfile {␊ |
65 | ␉u_int8_t reserved1[3];␉/* JumpBoot: 0xEB7690 */␊ |
66 | ␉u_int8_t bf_sysid[8];␉/* FileSystemName: 'EXFAT ' */␊ |
67 | ␉u_int8_t reserved2[53];␉/* MustBeZero */␊ |
68 | ␉u_int64_t bf_prtoff;␉␉/* PartitionOffset: In sectors; if 0, shall be ignored */␊ |
69 | ␉u_int64_t bf_vollen;␉␉/* VolumeLength: Size of exFAT volume in sectors */␊ |
70 | ␉u_int32_t bf_fatoff;␉␉/* FatOffset: In sectors */␊ |
71 | ␉u_int32_t bf_fatlen;␉␉/* FatLength: In sectors. May exceed the required space in order to align the second FAT */␊ |
72 | ␉u_int32_t bf_cloff;␉␉/* ClusterHeapOffset: In sectors. */␊ |
73 | ␉u_int32_t bf_clcnt;␉␉/* ClusterCount: 2^32-11 is the maximum number of clusters could be described. */␊ |
74 | ␉u_int32_t bf_rdircl;␉␉/* RootDirectoryCluster. */␊ |
75 | ␉u_int32_t bf_volsn;␉␉/* VolumeSerialNumber. */␊ |
76 | ␉u_int16_t bf_fsrev;␉␉/* FileSystemRevision: as MAJOR.minor, major revision is high byte, minor is low byte; currently 01.00. */␊ |
77 | ␉u_int16_t bf_volflags;␉/* VolumeFlags. */␊ |
78 | ␉u_int8_t bf_bpss;␉␉/* BytesPerSectorShift: Power of 2. Minimum 9 (512 bytes per sector), maximum 12 (4096 bytes per sector) */␊ |
79 | ␉u_int8_t bf_spcs;␉␉/* SectorsPerClusterShift: Power of 2. Minimum 0 (1 sector per cluster), maximum 25 – BytesPerSectorShift, so max cluster size is 32 MB */␊ |
80 | ␉u_int8_t bf_nfats;␉␉/* NumberOfFats: 2 is for TexFAT only */␊ |
81 | ␉u_int8_t bf_drvs;␉␉/* DriveSelect: Extended INT 13h drive number; typically 0x80 */␊ |
82 | ␉u_int8_t bf_pused;␉␉/* PercentInUse: 0..100 – percentage of allocated clusters rounded down to the integer 0xFF – percentage is not available */␊ |
83 | ␉u_int8_t reserved3[7];␉/* Reserved */␊ |
84 | ␉u_int8_t bootcode[390];␉/* BootCode */␊ |
85 | ␉u_int16_t bf_bsig;␉␉/* BootSignature: 0xAA55 */␊ |
86 | };␊ |
87 | ␊ |
88 | struct direntry_label {␊ |
89 | ␉u_int8_t type;␉␉␉/* EntryType: 0x83 (or 0x03 if label is empty) */␊ |
90 | ␉u_int8_t llen;␉␉␉/* CharacterCount: Length in Unicode characters (max 11) */␊ |
91 | ␉u_int16_t label[11];␉␉/* VolumeLabel: Unicode characters (max 11) */␊ |
92 | ␉u_int8_t reserved1[8];␉/* Reserved */␊ |
93 | };␊ |
94 | ␊ |
95 | ␊ |
96 | /**␊ |
97 | * Reads volume label into str.␊ |
98 | * Reads boot sector, performs dome checking, loads root dir␊ |
99 | * and parses volume label.␊ |
100 | */␊ |
101 | void␊ |
102 | EXFATGetDescription(CICell ih, char *str, long strMaxLen)␊ |
103 | {␊ |
104 | struct exfatbootfile *boot;␊ |
105 | u_int32_t bytesPerSector = 0;␊ |
106 | u_int32_t sectorsPerCluster = 0;␊ |
107 | long long rdirOffset = 0;␊ |
108 | char *buf = NULL;␊ |
109 | struct direntry_label *dire = NULL;␊ |
110 | int loopControl = 0;␊ |
111 | ␊ |
112 | DBG("EXFAT: start %x:%x\n", ih->biosdev, ih->part_no);␊ |
113 | ␉␊ |
114 | buf = (char *)malloc(MAX_BLOCK_SIZE);␊ |
115 | if (buf == 0)␊ |
116 | {␊ |
117 | goto error;␊ |
118 | }␊ |
119 | ␊ |
120 | /*␊ |
121 | * Read the boot sector, check signatures, and do some minimal␊ |
122 | * sanity checking. NOTE: the size of the read below is intended␊ |
123 | * to be a multiple of all supported block sizes, so we don't␊ |
124 | * have to determine or change the device's block size.␊ |
125 | */␊ |
126 | Seek(ih, 0);␊ |
127 | Read(ih, (long)buf, MAX_BLOCK_SIZE);␊ |
128 | ␊ |
129 | // take our boot structure␊ |
130 | boot = (struct exfatbootfile *) buf;␊ |
131 | ␊ |
132 | /*␊ |
133 | * The first three bytes are an Intel x86 jump instruction. I assume it␊ |
134 | * can be the same forms as DOS FAT:␊ |
135 | * 0xE9 0x?? 0x??␊ |
136 | * 0xEC 0x?? 0x90␊ |
137 | * where 0x?? means any byte value is OK.␊ |
138 | */␊ |
139 | if (boot->reserved1[0] != 0xE9␊ |
140 | && (boot->reserved1[0] != 0xEB || boot->reserved1[2] != 0x90))␊ |
141 | {␊ |
142 | goto error;␊ |
143 | }␊ |
144 | ␊ |
145 | // Check the "EXFAT " signature.␊ |
146 | if (memcmp((const char *)boot->bf_sysid, EXFAT_BBID, EXFAT_BBIDLEN) != 0)␊ |
147 | {␊ |
148 | goto error;␊ |
149 | }␊ |
150 | ␊ |
151 | /*␊ |
152 | * Make sure the bytes per sector and sectors per cluster are␊ |
153 | * powers of two, and within reasonable ranges.␊ |
154 | */␊ |
155 | bytesPerSector = 1 << boot->bf_bpss;␉/* Just one byte; no swapping needed */␊ |
156 | DBG("EXFAT: bpss=%d, bytesPerSector=%d\n", boot->bf_bpss, bytesPerSector);␊ |
157 | if (boot->bf_bpss < 9 || boot->bf_bpss > 12)␊ |
158 | {␊ |
159 | DBG("EXFAT: invalid bytes per sector shift(%d)\n", boot->bf_bpss);␊ |
160 | goto error;␊ |
161 | }␊ |
162 | ␊ |
163 | sectorsPerCluster = 1 << boot->bf_spcs;␉/* Just one byte; no swapping needed */␊ |
164 | DBG("EXFAT: spcs=%d, sectorsPerCluster=%d\n", boot->bf_spcs, sectorsPerCluster);␊ |
165 | if (boot->bf_spcs > (25 - boot->bf_bpss))␊ |
166 | {␊ |
167 | DBG("EXFAT: invalid sectors per cluster shift (%d)\n", boot->bf_spcs);␊ |
168 | goto error;␊ |
169 | }␊ |
170 | ␊ |
171 | // calculate root dir cluster offset␊ |
172 | rdirOffset = boot->bf_cloff + (boot->bf_rdircl - 2) * sectorsPerCluster;␊ |
173 | DBG("EXFAT: rdirOffset=%d\n", rdirOffset);␊ |
174 | ␊ |
175 | // load MAX_BLOCK_SIZE bytes of root dir␊ |
176 | Seek(ih, rdirOffset * bytesPerSector);␊ |
177 | Read(ih, (long)buf, MAX_BLOCK_SIZE);␊ |
178 | DBG("buf 0 1 2 = %x %x %x\n", 0x00ff & buf[0], 0x00ff & buf[1], 0x00ff & buf[2]);␊ |
179 | ␊ |
180 | str[0] = '\0';␊ |
181 | ␊ |
182 | /*␊ |
183 | * Search for volume label dir entry (type 0x83), convert from unicode and put to str.␊ |
184 | * Set loopControl var to avoid searching outside of buf.␊ |
185 | */␊ |
186 | loopControl = MAX_BLOCK_SIZE / sizeof(struct direntry_label);␊ |
187 | dire = (struct direntry_label *)buf;␊ |
188 | while (loopControl && dire->type && dire->type != 0x83)␊ |
189 | {␊ |
190 | dire++;␊ |
191 | loopControl--;␊ |
192 | }␊ |
193 | if (dire->type == 0x83 && dire->llen > 0 && dire->llen <= 11)␊ |
194 | {␊ |
195 | utf_encodestr( dire->label, (int)dire->llen, (u_int8_t *)str, strMaxLen, OSLittleEndian );␊ |
196 | }␊ |
197 | DBG("EXFAT: label=%s\n", str);␊ |
198 | ␊ |
199 | free(buf);␊ |
200 | PAUSE();␊ |
201 | return;␊ |
202 | ␊ |
203 | error:␊ |
204 | if (buf) free(buf);␊ |
205 | DBG("EXFAT: error\n");␊ |
206 | PAUSE();␊ |
207 | return;␊ |
208 | }␊ |
209 | ␊ |
210 | /**␊ |
211 | * Sets UUID to uuidStr.␊ |
212 | * Reads the boot sector, does some checking, generates UUID␊ |
213 | * (like the one you get on Windows???)␊ |
214 | */␊ |
215 | long EXFATGetUUID(CICell ih, char *uuidStr)␊ |
216 | {␊ |
217 | struct exfatbootfile *boot;␊ |
218 | void *buf = malloc(MAX_BLOCK_SIZE);␊ |
219 | if ( !buf )␊ |
220 | return -1;␊ |
221 | ␊ |
222 | /*␊ |
223 | * Read the boot sector, check signatures, and do some minimal␊ |
224 | * sanity checking.␉ NOTE: the size of the read below is intended␊ |
225 | * to be a multiple of all supported block sizes, so we don't␊ |
226 | * have to determine or change the device's block size.␊ |
227 | */␊ |
228 | Seek(ih, 0);␊ |
229 | Read(ih, (long)buf, MAX_BLOCK_SIZE);␊ |
230 | ␊ |
231 | boot = (struct exfatbootfile *) buf;␊ |
232 | ␊ |
233 | /*␊ |
234 | * Check the "EXFAT " signature.␊ |
235 | */␊ |
236 | if (memcmp((const char *)boot->bf_sysid, EXFAT_BBID, EXFAT_BBIDLEN) != 0)␊ |
237 | return -1;␊ |
238 | ␊ |
239 | // Check for non-null volume serial number␊ |
240 | if( !boot->bf_volsn )␊ |
241 | return -1;␊ |
242 | ␊ |
243 | // Use UUID like the one you get on Windows␊ |
244 | sprintf(uuidStr, "%04X-%04X", (unsigned short)(boot->bf_volsn >> 16) & 0xFFFF,␊ |
245 | (unsigned short)boot->bf_volsn & 0xFFFF);␊ |
246 | ␊ |
247 | DBG("EXFATGetUUID: %x:%x = %s\n", ih->biosdev, ih->part_no, uuidStr);␊ |
248 | return 0;␊ |
249 | } ␊ |
250 | ␊ |
251 | /**␊ |
252 | * Returns true if given buffer is the boot rec of the EXFAT volume.␊ |
253 | */␊ |
254 | bool EXFATProbe(const void * buffer)␊ |
255 | {␊ |
256 | bool result = false;␊ |
257 | ␊ |
258 | // boot sector structure␊ |
259 | const struct exfatbootfile␉* boot = buffer;␊ |
260 | ␊ |
261 | // Looking for EXFAT signature.␊ |
262 | if (memcmp((const char *)boot->bf_sysid, EXFAT_BBID, EXFAT_BBIDLEN) == 0)␊ |
263 | result = true;␊ |
264 | ␉␊ |
265 | DBG("EXFATProbe: %d\n", result ? 1 : 0);␊ |
266 | return result;␊ |
267 | }␊ |
268 | |