aboutsummaryrefslogtreecommitdiff
path: root/util-linux/volume_id/util.c
blob: c4d20ba470245a48f01899813d3d67f642a2f472 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
/*
 * volume_id - reads filesystem label and uuid
 *
 * Copyright (C) 2005 Kay Sievers <kay.sievers@vrfy.org>
 *
 *	This library is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU Lesser General Public
 *	License as published by the Free Software Foundation; either
 *	version 2.1 of the License, or (at your option) any later version.
 *
 *	This library is distributed in the hope that it will be useful,
 *	but WITHOUT ANY WARRANTY; without even the implied warranty of
 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 *	Lesser General Public License for more details.
 *
 *	You should have received a copy of the GNU Lesser General Public
 *	License along with this library; if not, write to the Free Software
 *	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include "volume_id_internal.h"

void volume_id_set_unicode16(char *str, size_t len, const uint8_t *buf, enum endian endianess, size_t count)
{
	unsigned i, j;
	unsigned c;

	j = 0;
	for (i = 0; i + 2 <= count; i += 2) {
		if (endianess == LE)
			c = (buf[i+1] << 8) | buf[i];
		else
			c = (buf[i] << 8) | buf[i+1];
		if (c == 0) {
			str[j] = '\0';
			break;
		} else if (c < 0x80) {
			if (j+1 >= len)
				break;
			str[j++] = (uint8_t) c;
		} else if (c < 0x800) {
			if (j+2 >= len)
				break;
			str[j++] = (uint8_t) (0xc0 | (c >> 6));
			str[j++] = (uint8_t) (0x80 | (c & 0x3f));
		} else {
			if (j+3 >= len)
				break;
			str[j++] = (uint8_t) (0xe0 | (c >> 12));
			str[j++] = (uint8_t) (0x80 | ((c >> 6) & 0x3f));
			str[j++] = (uint8_t) (0x80 | (c & 0x3f));
		}
	}
	str[j] = '\0';
}

#ifdef UNUSED
static const char *usage_to_string(enum volume_id_usage usage_id)
{
	switch (usage_id) {
	case VOLUME_ID_FILESYSTEM:
		return "filesystem";
	case VOLUME_ID_PARTITIONTABLE:
		return "partitiontable";
	case VOLUME_ID_OTHER:
		return "other";
	case VOLUME_ID_RAID:
		return "raid";
	case VOLUME_ID_DISKLABEL:
		return "disklabel";
	case VOLUME_ID_CRYPTO:
		return "crypto";
	case VOLUME_ID_UNPROBED:
		return "unprobed";
	case VOLUME_ID_UNUSED:
		return "unused";
	}
	return NULL;
}

void volume_id_set_usage_part(struct volume_id_partition *part, enum volume_id_usage usage_id)
{
	part->usage_id = usage_id;
	part->usage = usage_to_string(usage_id);
}

void volume_id_set_usage(struct volume_id *id, enum volume_id_usage usage_id)
{
	id->usage_id = usage_id;
	id->usage = usage_to_string(usage_id);
}

void volume_id_set_label_raw(struct volume_id *id, const uint8_t *buf, size_t count)
{
	memcpy(id->label_raw, buf, count);
	id->label_raw_len = count;
}
#endif

#ifdef NOT_NEEDED
static size_t strnlen(const char *s, size_t maxlen)
{
	size_t i;
	if (!maxlen) return 0;
	if (!s) return 0;
	for (i = 0; *s && i < maxlen; ++s) ++i;
	return i;
}
#endif

void volume_id_set_label_string(struct volume_id *id, const uint8_t *buf, size_t count)
{
	unsigned i;

	memcpy(id->label, buf, count);

	/* remove trailing whitespace */
	i = strnlen(id->label, count);
	while (i--) {
		if (!isspace(id->label[i]))
			break;
	}
	id->label[i+1] = '\0';
}

void volume_id_set_label_unicode16(struct volume_id *id, const uint8_t *buf, enum endian endianess, size_t count)
{
	 volume_id_set_unicode16(id->label, sizeof(id->label), buf, endianess, count);
}

void volume_id_set_uuid(struct volume_id *id, const uint8_t *buf, enum uuid_format format)
{
	unsigned i;
	unsigned count = 0;

	switch (format) {
	case UUID_DOS:
		count = 4;
		break;
	case UUID_NTFS:
	case UUID_HFS:
		count = 8;
		break;
	case UUID_DCE:
		count = 16;
		break;
	case UUID_DCE_STRING:
		/* 36 is ok, id->uuid has one extra byte for NUL */
		count = VOLUME_ID_UUID_SIZE;
		break;
	}
//	memcpy(id->uuid_raw, buf, count);
//	id->uuid_raw_len = count;

	/* if set, create string in the same format, the native platform uses */
	for (i = 0; i < count; i++)
		if (buf[i] != 0)
			goto set;
	return; /* all bytes are zero, leave it empty ("") */

set:
	switch (format) {
	case UUID_DOS:
		sprintf(id->uuid, "%02X%02X-%02X%02X",
			buf[3], buf[2], buf[1], buf[0]);
		break;
	case UUID_NTFS:
		sprintf(id->uuid, "%02X%02X%02X%02X%02X%02X%02X%02X",
			buf[7], buf[6], buf[5], buf[4],
			buf[3], buf[2], buf[1], buf[0]);
		break;
	case UUID_HFS:
		sprintf(id->uuid, "%02X%02X%02X%02X%02X%02X%02X%02X",
			buf[0], buf[1], buf[2], buf[3],
			buf[4], buf[5], buf[6], buf[7]);
		break;
	case UUID_DCE:
		sprintf(id->uuid,
			"%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
			buf[0], buf[1], buf[2], buf[3],
			buf[4], buf[5],
			buf[6], buf[7],
			buf[8], buf[9],
			buf[10], buf[11], buf[12], buf[13], buf[14], buf[15]);
		break;
	case UUID_DCE_STRING:
		memcpy(id->uuid, buf, count);
		id->uuid[count] = '\0';
		break;
	}
}

/* Do not use xlseek here. With it, single corrupted filesystem
 * may result in attempt to seek past device -> exit.
 * It's better to ignore such fs and continue.  */
void *volume_id_get_buffer(struct volume_id *id, uint64_t off, size_t len)
{
	ssize_t buf_len;

	dbg("get buffer off 0x%llx(%llu), len 0x%zx", (unsigned long long) off, (unsigned long long) off, len);
	/* check if requested area fits in superblock buffer */
	if (off + len <= SB_BUFFER_SIZE) {
		if (id->sbbuf == NULL) {
			id->sbbuf = xmalloc(SB_BUFFER_SIZE);
		}

		/* check if we need to read */
		if ((off + len) > id->sbbuf_len) {
			dbg("read sbbuf len:0x%llx", (unsigned long long) (off + len));
			if (lseek(id->fd, 0, SEEK_SET) != 0) {
				dbg("seek(0) failed");
				return NULL;
			}
			buf_len = full_read(id->fd, id->sbbuf, off + len);
			if (buf_len < 0) {
				dbg("read failed (%s)", strerror(errno));
				return NULL;
			}
			dbg("got 0x%zx (%zi) bytes", buf_len, buf_len);
			id->sbbuf_len = buf_len;
			if ((uint64_t)buf_len < off + len) {
				dbg("requested 0x%zx bytes, got only 0x%zx bytes", len, buf_len);
				return NULL;
			}
		}

		return &(id->sbbuf[off]);
	}

	if (len > SEEK_BUFFER_SIZE) {
		dbg("seek buffer too small %d", SEEK_BUFFER_SIZE);
		return NULL;
	}

	/* get seek buffer */
	if (id->seekbuf == NULL) {
		id->seekbuf = xmalloc(SEEK_BUFFER_SIZE);
	}

	/* check if we need to read */
	if ((off < id->seekbuf_off) || ((off + len) > (id->seekbuf_off + id->seekbuf_len))) {
		dbg("read seekbuf off:0x%llx len:0x%zx", (unsigned long long) off, len);
		if (lseek(id->fd, off, SEEK_SET) != off) {
			dbg("seek(0x%llx) failed", (unsigned long long) off);
			return NULL;
		}
		buf_len = full_read(id->fd, id->seekbuf, len);
		if (buf_len < 0) {
			dbg("read failed (%s)", strerror(errno));
			return NULL;
		}
		dbg("got 0x%zx (%zi) bytes", buf_len, buf_len);
		id->seekbuf_off = off;
		id->seekbuf_len = buf_len;
		if ((size_t)buf_len < len) {
			dbg("requested 0x%zx bytes, got only 0x%zx bytes", len, buf_len);
			return NULL;
		}
	}

	return &(id->seekbuf[off - id->seekbuf_off]);
}

void volume_id_free_buffer(struct volume_id *id)
{
	free(id->sbbuf);
	id->sbbuf = NULL;
	id->sbbuf_len = 0;
	free(id->seekbuf);
	id->seekbuf = NULL;
	id->seekbuf_len = 0;
}