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1/*
2 * Copyright (c) 2004 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * Copyright (c) 1999-2004 Apple Computer, Inc. All Rights Reserved.
7 *
8 * This file contains Original Code and/or Modifications of Original Code
9 * as defined in and that are subject to the Apple Public Source License
10 * Version 2.0 (the 'License'). You may not use this file except in
11 * compliance with the License. Please obtain a copy of the License at
12 * http://www.opensource.apple.com/apsl/ and read it before using this
13 * file.
14 *
15 * The Original Code and all software distributed under the License are
16 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
17 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
18 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
20 * Please see the License for the specific language governing rights and
21 * limitations under the License.
22 *
23 * @APPLE_LICENSE_HEADER_END@
24 */
25
26#include "libsaio.h"
27#include "sl.h"
28
29/*
30 * dmazar, 14/7/2011 - support for EXFAT volume label reading
31 */
32#include "exfat.h"
33
34#define BYTE_ORDER_MARK0xFEFF
35
36#include "ntfs_private.h"
37
38#define FS_TYPE"ntfs"
39#define FS_NAME_FILE"NTFS"
40
41#define MAX_BLOCK_SIZE2048
42#define MAX_CLUSTER_SIZE32768
43
44#define LABEL_LENGTH1024
45#define UNKNOWN_LABEL"Untitled NTFS"
46
47#define FSUR_IO_FAIL -1
48#define FSUR_UNRECOGNIZED -1
49#define FSUR_RECOGNIZED 0
50
51#define ERROR -1
52
53/*
54 * Process per-sector "fixups" that NTFS uses to detect corruption of
55 * multi-sector data structures, like MFT records.
56 */
57static int
58ntfs_fixup(
59 char *buf,
60 size_t len,
61 u_int32_t magic,
62 u_int32_t bytesPerSector)
63{
64struct fixuphdr *fhp = (struct fixuphdr *) buf;
65int i;
66u_int16_t fixup;
67u_int16_t *fxp;
68u_int16_t *cfxp;
69 u_int32_tfixup_magic;
70 u_int16_tfixup_count;
71 u_int16_tfixup_offset;
72
73 fixup_magic = OSReadLittleInt32(&fhp->fh_magic,0);
74if (fixup_magic != magic) {
75error("ntfs_fixup: magic doesn't match: %08x != %08x\n",
76 fixup_magic, magic);
77return (ERROR);
78}
79 fixup_count = OSReadLittleInt16(&fhp->fh_fnum,0);
80if ((fixup_count - 1) * bytesPerSector != len) {
81error("ntfs_fixup: " \
82 "bad fixups number: %d for %ld bytes block\n",
83 fixup_count, (long)len);/* XXX printf kludge */
84return (ERROR);
85}
86 fixup_offset = OSReadLittleInt16(&fhp->fh_foff,0);
87if (fixup_offset >= len) {
88error("ntfs_fixup: invalid offset: %x", fixup_offset);
89return (ERROR);
90}
91fxp = (u_int16_t *) (buf + fixup_offset);
92cfxp = (u_int16_t *) (buf + bytesPerSector - 2);
93fixup = *fxp++;
94for (i = 1; i < fixup_count; i++, fxp++) {
95if (*cfxp != fixup) {
96error("ntfs_fixup: fixup %d doesn't match\n", i);
97return (ERROR);
98}
99*cfxp = *fxp;
100 cfxp = (u_int16_t *)(((caddr_t)cfxp) + bytesPerSector);
101}
102return (0);
103}
104
105/*
106 * Find a resident attribute of a given type. Returns a pointer to the
107 * attribute data, and its size in bytes.
108 */
109static int
110ntfs_find_attr(
111 char *buf,
112 u_int32_t attrType,
113 void **attrData,
114 size_t *attrSize)
115{
116 struct filerec *filerec;
117 struct attr *attr;
118 u_int16_t offset;
119
120 filerec = (struct filerec *) buf;
121 offset = OSReadLittleInt16(&filerec->fr_attroff,0);
122 attr = (struct attr *) (buf + offset);
123
124
125 while (attr->a_hdr.a_type != 0xFFFFFFFF)/* same for big/little endian */
126 {
127 if (OSReadLittleInt32(&attr->a_hdr.a_type,0) == attrType)
128 {
129 if (attr->a_hdr.a_flag != 0)
130 {
131 //verbose("NTFS: attriubte 0x%X is non-resident\n", attrType);
132 return 1;
133 }
134
135 *attrSize = OSReadLittleInt16(&attr->a_r.a_datalen,0);
136 *attrData = buf + offset + OSReadLittleInt16(&attr->a_r.a_dataoff,0);
137 return 0;/* found it! */
138 }
139
140 /* Skip to the next attribute */
141 offset += OSReadLittleInt32(&attr->a_hdr.reclen,0);
142 attr = (struct attr *) (buf + offset);
143 }
144
145 return 1;/* No matching attrType found */
146}
147
148/*
149 * Examine a volume to see if we recognize it as a mountable.
150 */
151void
152NTFSGetDescription(CICell ih, char *str, long strMaxLen)
153{
154 struct bootfile *boot;
155 unsigned bytesPerSector;
156 unsigned sectorsPerCluster;
157 int mftRecordSize;
158 u_int64_t totalClusters;
159 u_int64_t cluster, mftCluster;
160 size_t mftOffset;
161 void *nameAttr;
162 size_t nameSize;
163 char *buf;
164
165 buf = (char *)malloc(MAX_CLUSTER_SIZE);
166 if (buf == 0) {
167 goto error;
168 }
169
170 /*
171 * Read the boot sector, check signatures, and do some minimal
172 * sanity checking. NOTE: the size of the read below is intended
173 * to be a multiple of all supported block sizes, so we don't
174 * have to determine or change the device's block size.
175 */
176 Seek(ih, 0);
177 Read(ih, (long)buf, MAX_BLOCK_SIZE);
178
179 boot = (struct bootfile *) buf;
180
181 /*
182 * The first three bytes are an Intel x86 jump instruction. I assume it
183 * can be the same forms as DOS FAT:
184 * 0xE9 0x?? 0x??
185 * 0xEC 0x?? 0x90
186 * where 0x?? means any byte value is OK.
187 */
188 if (boot->reserved1[0] != 0xE9
189 && (boot->reserved1[0] != 0xEB || boot->reserved1[2] != 0x90))
190 {
191 goto error;
192 }
193
194 /*
195 * Check the "NTFS " signature.
196 */
197 if (memcmp((const char *)boot->bf_sysid, "NTFS ", 8) != 0)
198 {
199 /*
200 * Check for EXFAT. Finish by jumping to error to free buf,
201 * although if it is EXFAT then it's no an error.
202 */
203 EXFATGetDescription(ih, str, strMaxLen);
204 goto error;
205 }
206
207 /*
208 * Make sure the bytes per sector and sectors per cluster are
209 * powers of two, and within reasonable ranges.
210 */
211 bytesPerSector = OSReadLittleInt16(&boot->bf_bps,0);
212 if ((bytesPerSector & (bytesPerSector-1)) || bytesPerSector < 512 || bytesPerSector > 32768)
213 {
214 //verbose("NTFS: invalid bytes per sector (%d)\n", bytesPerSector);
215 goto error;
216 }
217
218 sectorsPerCluster = boot->bf_spc;/* Just one byte; no swapping needed */
219 if ((sectorsPerCluster & (sectorsPerCluster-1)) || sectorsPerCluster > 128)
220 {
221 //verbose("NTFS: invalid sectors per cluster (%d)\n", bytesPerSector);
222 goto error;
223 }
224
225 /*
226 * Calculate the number of clusters from the number of sectors.
227 * Then bounds check the $MFT and $MFTMirr clusters.
228 */
229 totalClusters = OSReadLittleInt64(&boot->bf_spv,0) / sectorsPerCluster;
230 mftCluster = OSReadLittleInt64(&boot->bf_mftcn,0);
231 if (mftCluster > totalClusters)
232 {
233 ////verbose("NTFS: invalid $MFT cluster (%lld)\n", mftCluster);
234 goto error;
235 }
236 cluster = OSReadLittleInt64(&boot->bf_mftmirrcn,0);
237 if (cluster > totalClusters)
238 {
239 //verbose("NTFS: invalid $MFTMirr cluster (%lld)\n", cluster);
240 goto error;
241 }
242
243 /*
244 * Determine the size of an MFT record.
245 */
246 mftRecordSize = (int8_t) boot->bf_mftrecsz;
247 if (mftRecordSize < 0)
248 mftRecordSize = 1 << -mftRecordSize;
249 else
250 mftRecordSize *= bytesPerSector * sectorsPerCluster;
251 //verbose("NTFS: MFT record size = %d\n", mftRecordSize);
252
253 /*
254 * Read the MFT record for $Volume. This assumes the first four
255 * file records in the MFT are contiguous; if they aren't, we
256 * would have to map the $MFT itself.
257 *
258 * This will fail if the device sector size is larger than the
259 * MFT record size, since the $Volume record won't be aligned
260 * on a sector boundary.
261 */
262 mftOffset = mftCluster * sectorsPerCluster * bytesPerSector;
263 mftOffset += mftRecordSize * NTFS_VOLUMEINO;
264
265 Seek(ih, mftOffset);
266 Read(ih, (long)buf, mftRecordSize);
267#if UNUSED
268 if (lseek(fd, mftOffset, SEEK_SET) == -1)
269 {
270 //verbose("NTFS: lseek to $Volume failed: %s\n", strerror(errno));
271 goto error;
272 }
273 if (read(fd, buf, mftRecordSize) != mftRecordSize)
274 {
275 //verbose("NTFS: error reading MFT $Volume record: %s\n",
276 strerror(errno));
277 goto error;
278 }
279#endif
280
281 if (ntfs_fixup(buf, mftRecordSize, NTFS_FILEMAGIC, bytesPerSector) != 0)
282 {
283 //verbose("NTFS: block fixup failed\n");
284 goto error;
285 }
286
287 /*
288 * Loop over the attributes, looking for $VOLUME_NAME (0x60).
289 */
290 if(ntfs_find_attr(buf, NTFS_A_VOLUMENAME, &nameAttr, &nameSize) != 0)
291 {
292 //verbose("NTFS: $VOLUME_NAME attribute not found\n");
293 goto error;
294 }
295
296 str[0] = '\0';
297
298 utf_encodestr( nameAttr, nameSize / 2, (u_int8_t *)str, strMaxLen, OSLittleEndian );
299
300 free(buf);
301 return;
302
303 error:
304 if (buf) free(buf);
305 return;
306}
307
308long NTFSGetUUID(CICell ih, char *uuidStr)
309{
310bool NTFSProbe(const void*);
311
312struct bootfile *boot;
313void *buf = malloc(MAX_BLOCK_SIZE);
314if ( !buf )
315return -1;
316
317/*
318 * Read the boot sector, check signatures, and do some minimal
319 * sanity checking. NOTE: the size of the read below is intended
320 * to be a multiple of all supported block sizes, so we don't
321 * have to determine or change the device's block size.
322 */
323Seek(ih, 0);
324Read(ih, (long)buf, MAX_BLOCK_SIZE);
325
326boot = (struct bootfile *) buf;
327
328// Check for NTFS signature
329if ( memcmp((void*)boot->bf_sysid, NTFS_BBID, NTFS_BBIDLEN) != 0 ) {
330// If not NTFS, maybe it is EXFAT
331return EXFATGetUUID(ih, uuidStr);
332}
333
334// Check for non-null volume serial number
335if( !boot->bf_volsn )
336return -1;
337
338// Use UUID like the one you get on Windows
339sprintf(uuidStr, "%04X-%04X",(unsigned short)(boot->bf_volsn >> 16) & 0xFFFF,
340(unsigned short)boot->bf_volsn & 0xFFFF);
341
342return 0;
343}
344
345bool NTFSProbe(const void * buffer)
346{
347bool result = false;
348
349const struct bootfile* part_bootfile = buffer;// NTFS boot sector structure
350
351// Looking for NTFS signature.
352if (strncmp((const char *)part_bootfile->bf_sysid, NTFS_BBID, NTFS_BBIDLEN) == 0)
353result = true;
354
355// If not NTFS, maybe it is EXFAT
356if (!result)
357result = EXFATProbe(buffer);
358
359return result;
360}
361

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