1 /* Copyright (c) 2008, XenSource Inc.
2 * All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are met:
6 * * Redistributions of source code must retain the above copyright
7 * notice, this list of conditions and the following disclaimer.
8 * * Redistributions in binary form must reproduce the above copyright
9 * notice, this list of conditions and the following disclaimer in the
10 * documentation and/or other materials provided with the distribution.
11 * * Neither the name of XenSource Inc. nor the names of its contributors
12 * may be used to endorse or promote products derived from this software
13 * without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
19 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
22 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
23 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
24 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27 #ifndef _VHD_LIB_H_
28 #define _VHD_LIB_H_
29
30 #include <string.h>
31 #if defined(__linux__)
32 #include <endian.h>
33 #include <byteswap.h>
34 #elif defined(__NetBSD__)
35 #include <sys/endian.h>
36 #include <sys/bswap.h>
37 #endif
38
39 #include "vhd-uuid.h"
40 #include "vhd.h"
41
42 #ifndef O_LARGEFILE
43 #define O_LARGEFILE 0
44 #endif
45
46 #if BYTE_ORDER == LITTLE_ENDIAN
47 #if defined(__linux__)
48 #define BE16_IN(foo) (*(foo)) = bswap_16(*(foo))
49 #define BE32_IN(foo) (*(foo)) = bswap_32(*(foo))
50 #define BE64_IN(foo) (*(foo)) = bswap_64(*(foo))
51 #define BE16_OUT(foo) (*(foo)) = bswap_16(*(foo))
52 #define BE32_OUT(foo) (*(foo)) = bswap_32(*(foo))
53 #define BE64_OUT(foo) (*(foo)) = bswap_64(*(foo))
54 #elif defined(__NetBSD__)
55 #define BE16_IN(foo) (*(foo)) = bswap16(*(foo))
56 #define BE32_IN(foo) (*(foo)) = bswap32(*(foo))
57 #define BE64_IN(foo) (*(foo)) = bswap64(*(foo))
58 #define BE16_OUT(foo) (*(foo)) = bswap16(*(foo))
59 #define BE32_OUT(foo) (*(foo)) = bswap32(*(foo))
60 #define BE64_OUT(foo) (*(foo)) = bswap64(*(foo))
61 #endif
62 #else
63 #define BE16_IN(foo)
64 #define BE32_IN(foo)
65 #define BE64_IN(foo)
66 #define BE32_OUT(foo)
67 #define BE32_OUT(foo)
68 #define BE64_OUT(foo)
69 #endif
70
71 #define MIN(a, b) (((a) < (b)) ? (a) : (b))
72 #define MAX(a, b) (((a) > (b)) ? (a) : (b))
73
74 #define VHD_MAX_NAME_LEN 1024
75
76 #define VHD_BLOCK_SHIFT 21
77 #define VHD_BLOCK_SIZE (1ULL << VHD_BLOCK_SHIFT)
78
79 #define UTF_16 "UTF-16"
80 #define UTF_16LE "UTF-16LE"
81 #define UTF_16BE "UTF-16BE"
82
83 #define VHD_OPEN_RDONLY 0x00001
84 #define VHD_OPEN_RDWR 0x00002
85 #define VHD_OPEN_FAST 0x00004
86 #define VHD_OPEN_STRICT 0x00008
87 #define VHD_OPEN_IGNORE_DISABLED 0x00010
88
89 #define VHD_FLAG_CREAT_PARENT_RAW 0x00001
90
91 #define vhd_flag_set(word, flag) ((word) |= (flag))
92 #define vhd_flag_clear(word, flag) ((word) &= ~(flag))
93 #define vhd_flag_test(word, flag) ((word) & (flag))
94
95
96 #define ENABLE_FAILURE_TESTING
97 #define FAIL_REPARENT_BEGIN 0
98 #define FAIL_REPARENT_LOCATOR 1
99 #define FAIL_REPARENT_END 2
100 #define FAIL_RESIZE_BEGIN 3
101 #define FAIL_RESIZE_DATA_MOVED 4
102 #define FAIL_RESIZE_METADATA_MOVED 5
103 #define FAIL_RESIZE_END 6
104 #define NUM_FAIL_TESTS 7
105
106 #ifdef ENABLE_FAILURE_TESTING
107 #define TEST_FAIL_AT(point) \
108 if (TEST_FAIL[point]) { \
109 printf("Failing at %s\n", ENV_VAR_FAIL[point]); exit(EINVAL); }
110 #define TEST_FAIL_EXTERN_VARS \
111 extern const char* ENV_VAR_FAIL[]; \
112 extern int TEST_FAIL[];
113 #else
114 #define TEST_FAIL_AT(point)
115 #define TEST_FAIL_EXTERN_VARS
116 #endif // ENABLE_FAILURE_TESTING
117
118
119 static const char VHD_POISON_COOKIE[] = "v_poison";
120
121 typedef struct hd_ftr vhd_footer_t;
122 typedef struct dd_hdr vhd_header_t;
123 typedef struct vhd_bat vhd_bat_t;
124 typedef struct vhd_batmap vhd_batmap_t;
125 typedef struct dd_batmap_hdr vhd_batmap_header_t;
126 typedef struct prt_loc vhd_parent_locator_t;
127 typedef struct vhd_context vhd_context_t;
128 typedef uint32_t vhd_flag_creat_t;
129
130 struct vhd_bat {
131 uint32_t spb;
132 uint32_t entries;
133 uint32_t *bat;
134 };
135
136 struct vhd_batmap {
137 vhd_batmap_header_t header;
138 char *map;
139 };
140
141 struct vhd_context {
142 int fd;
143 char *file;
144 int oflags;
145 int is_block;
146
147 uint32_t spb;
148 uint32_t bm_secs;
149
150 vhd_header_t header;
151 vhd_footer_t footer;
152 vhd_bat_t bat;
153 vhd_batmap_t batmap;
154 };
155
156 static inline uint32_t
secs_round_up(uint64_t bytes)157 secs_round_up(uint64_t bytes)
158 {
159 return ((bytes + (VHD_SECTOR_SIZE - 1)) >> VHD_SECTOR_SHIFT);
160 }
161
162 static inline uint32_t
secs_round_up_no_zero(uint64_t bytes)163 secs_round_up_no_zero(uint64_t bytes)
164 {
165 return (secs_round_up(bytes) ? : 1);
166 }
167
168 static inline uint64_t
vhd_sectors_to_bytes(uint64_t sectors)169 vhd_sectors_to_bytes(uint64_t sectors)
170 {
171 return sectors << VHD_SECTOR_SHIFT;
172 }
173
174 static inline uint64_t
vhd_bytes_padded(uint64_t bytes)175 vhd_bytes_padded(uint64_t bytes)
176 {
177 return vhd_sectors_to_bytes(secs_round_up_no_zero(bytes));
178 }
179
180 static inline int
vhd_type_dynamic(vhd_context_t * ctx)181 vhd_type_dynamic(vhd_context_t *ctx)
182 {
183 return (ctx->footer.type == HD_TYPE_DYNAMIC ||
184 ctx->footer.type == HD_TYPE_DIFF);
185 }
186
187 static inline int
vhd_creator_tapdisk(vhd_context_t * ctx)188 vhd_creator_tapdisk(vhd_context_t *ctx)
189 {
190 return !strncmp(ctx->footer.crtr_app, "tap", 3);
191 }
192
193 static inline int
vhd_disabled(vhd_context_t * ctx)194 vhd_disabled(vhd_context_t *ctx)
195 {
196 return (!memcmp(ctx->footer.cookie,
197 VHD_POISON_COOKIE, sizeof(ctx->footer.cookie)));
198 }
199
200 static inline size_t
vhd_parent_locator_size(vhd_parent_locator_t * loc)201 vhd_parent_locator_size(vhd_parent_locator_t *loc)
202 {
203 /*
204 * MICROSOFT_COMPAT
205 * data_space *should* be in sectors,
206 * but sometimes we find it in bytes
207 */
208 if (loc->data_space < 512)
209 return vhd_sectors_to_bytes(loc->data_space);
210 else if (loc->data_space % 512 == 0)
211 return loc->data_space;
212 else
213 return 0;
214 }
215
216 static inline int
vhd_parent_raw(vhd_context_t * ctx)217 vhd_parent_raw(vhd_context_t *ctx)
218 {
219 return vhd_uuid_is_nil(&ctx->header.prt_uuid);
220 }
221
222 void libvhd_set_log_level(int);
223
224 int vhd_test_file_fixed(const char *, int *);
225
226 uint32_t vhd_time(time_t time);
227 size_t vhd_time_to_string(uint32_t timestamp, char *target);
228 uint32_t vhd_chs(uint64_t size);
229
230 uint32_t vhd_checksum_footer(vhd_footer_t *);
231 uint32_t vhd_checksum_header(vhd_header_t *);
232 uint32_t vhd_checksum_batmap(vhd_batmap_t *);
233
234 void vhd_footer_in(vhd_footer_t *);
235 void vhd_footer_out(vhd_footer_t *);
236 void vhd_header_in(vhd_header_t *);
237 void vhd_header_out(vhd_header_t *);
238 void vhd_bat_in(vhd_bat_t *);
239 void vhd_bat_out(vhd_bat_t *);
240 void vhd_batmap_header_in(vhd_batmap_t *);
241 void vhd_batmap_header_out(vhd_batmap_t *);
242
243 int vhd_validate_footer(vhd_footer_t *footer);
244 int vhd_validate_header(vhd_header_t *header);
245 int vhd_validate_batmap_header(vhd_batmap_t *batmap);
246 int vhd_validate_batmap(vhd_batmap_t *batmap);
247 int vhd_validate_platform_code(uint32_t code);
248
249 int vhd_open(vhd_context_t *, const char *file, int flags);
250 void vhd_close(vhd_context_t *);
251 int vhd_create(const char *name, uint64_t bytes, int type, vhd_flag_creat_t);
252 /* vhd_snapshot: the bytes parameter is optional and can be 0 if the snapshot
253 * is to have the same size as the (first non-empty) parent */
254 int vhd_snapshot(const char *snapshot, uint64_t bytes, const char *parent,
255 vhd_flag_creat_t);
256
257 int vhd_hidden(vhd_context_t *, int *);
258 int vhd_chain_depth(vhd_context_t *, int *);
259
260 off_t vhd_position(vhd_context_t *);
261 int vhd_seek(vhd_context_t *, off_t, int);
262 int vhd_read(vhd_context_t *, void *, size_t);
263 int vhd_write(vhd_context_t *, void *, size_t);
264
265 int vhd_offset(vhd_context_t *, uint32_t, uint32_t *);
266
267 int vhd_end_of_headers(vhd_context_t *ctx, off_t *off);
268 int vhd_end_of_data(vhd_context_t *ctx, off_t *off);
269 int vhd_batmap_header_offset(vhd_context_t *ctx, off_t *off);
270
271 int vhd_get_header(vhd_context_t *);
272 int vhd_get_footer(vhd_context_t *);
273 int vhd_get_bat(vhd_context_t *);
274 int vhd_get_batmap(vhd_context_t *);
275
276 void vhd_put_header(vhd_context_t *);
277 void vhd_put_footer(vhd_context_t *);
278 void vhd_put_bat(vhd_context_t *);
279 void vhd_put_batmap(vhd_context_t *);
280
281 int vhd_has_batmap(vhd_context_t *);
282 int vhd_batmap_test(vhd_context_t *, vhd_batmap_t *, uint32_t);
283 void vhd_batmap_set(vhd_context_t *, vhd_batmap_t *, uint32_t);
284 void vhd_batmap_clear(vhd_context_t *, vhd_batmap_t *, uint32_t);
285
286 int vhd_get_phys_size(vhd_context_t *, off_t *);
287 int vhd_set_phys_size(vhd_context_t *, off_t);
288
289 int vhd_bitmap_test(vhd_context_t *, char *, uint32_t);
290 void vhd_bitmap_set(vhd_context_t *, char *, uint32_t);
291 void vhd_bitmap_clear(vhd_context_t *, char *, uint32_t);
292
293 int vhd_parent_locator_count(vhd_context_t *);
294 int vhd_parent_locator_get(vhd_context_t *, char **);
295 int vhd_parent_locator_read(vhd_context_t *, vhd_parent_locator_t *, char **);
296 int vhd_find_parent(vhd_context_t *, const char *, char **);
297 int vhd_parent_locator_write_at(vhd_context_t *, const char *,
298 off_t, uint32_t, size_t,
299 vhd_parent_locator_t *);
300
301 int vhd_header_decode_parent(vhd_context_t *, vhd_header_t *, char **);
302 int vhd_change_parent(vhd_context_t *, char *parent_path, int raw);
303
304 int vhd_read_footer(vhd_context_t *, vhd_footer_t *);
305 int vhd_read_footer_at(vhd_context_t *, vhd_footer_t *, off_t);
306 int vhd_read_footer_strict(vhd_context_t *, vhd_footer_t *);
307 int vhd_read_header(vhd_context_t *, vhd_header_t *);
308 int vhd_read_header_at(vhd_context_t *, vhd_header_t *, off_t);
309 int vhd_read_bat(vhd_context_t *, vhd_bat_t *);
310 int vhd_read_batmap(vhd_context_t *, vhd_batmap_t *);
311 int vhd_read_bitmap(vhd_context_t *, uint32_t block, char **bufp);
312 int vhd_read_block(vhd_context_t *, uint32_t block, char **bufp);
313
314 int vhd_write_footer(vhd_context_t *, vhd_footer_t *);
315 int vhd_write_footer_at(vhd_context_t *, vhd_footer_t *, off_t);
316 int vhd_write_header(vhd_context_t *, vhd_header_t *);
317 int vhd_write_header_at(vhd_context_t *, vhd_header_t *, off_t);
318 int vhd_write_bat(vhd_context_t *, vhd_bat_t *);
319 int vhd_write_batmap(vhd_context_t *, vhd_batmap_t *);
320 int vhd_write_bitmap(vhd_context_t *, uint32_t block, char *bitmap);
321 int vhd_write_block(vhd_context_t *, uint32_t block, char *data);
322
323 int vhd_io_read(vhd_context_t *, char *, uint64_t, uint32_t);
324 int vhd_io_write(vhd_context_t *, char *, uint64_t, uint32_t);
325
326 #endif
327