1 #ifndef _WIMLIB_HEADER_H
2 #define _WIMLIB_HEADER_H
4 #include "wimlib/resource.h"
5 #include "wimlib/types.h"
6 #include "wimlib/endianness.h"
8 /* Length of "Globally Unique ID" field in WIM header. */
11 /* Length of the WIM header on disk. */
12 #define WIM_HEADER_DISK_SIZE 208
14 /* Compressed resources in the WIM are divided into separated compressed chunks
15 * of this size. This value is unfortunately not configurable (at least when
16 * compatibility with Microsoft's software is desired). */
17 #define WIM_CHUNK_SIZE 32768
19 /* Version of the WIM file. There is an older version (used for prerelease
20 * versions of Windows Vista), but wimlib doesn't support it. The differences
21 * between the versions are undocumented. */
22 #define WIM_VERSION 0x10d00
24 /* Version number used for a different WIM format, which as of Windows 8 can be
25 * created by passing 0x20000000 in dwFlagsAndAttributes to WIMGAPI's
26 * WIMCreateFile() and specifying either NONE, XPRESS, or LZMS compression.
27 * This format is, however, currently undocumented by Microsoft and is seemingly
28 * incompatible with their own ImageX and Dism programs. wimlib does not yet
29 * support this format. */
30 #define WIM_MYSTERY_VERSION 0xe00
32 /* WIM magic characters, translated to a single 64-bit little endian number. */
34 cpu_to_le64(((u64)'M' << 0) | \
43 /* wimlib pipable WIM magic characters, translated to a single 64-bit little
46 cpu_to_le64(((u64)'W' << 0) | \
55 /* On-disk format of the WIM header. */
56 struct wim_header_disk {
58 /* Magic characters "MSWIM\0\0\0" */
61 /* Size of the WIM header, in bytes; WIM_HEADER_DISK_SIZE expected
62 * (currently the only supported value). */
65 /* Version of the WIM file; WIM_VERSION expected (currently the only
66 * supported value). */
69 /* Flags for the WIM file (WIM_HDR_FLAG_*) */
72 /* Uncompressed chunk size of resources in the WIM. 0 if the WIM is
73 * uncompressed. If compressed, WIM_CHUNK_SIZE is expected (currently
74 * the only supported value). */
77 /* Globally unique identifier for the WIM file. Basically a bunch of
81 /* Number of this WIM part in the split WIM file, indexed from 1, or 1
82 * if the WIM is not split. */
85 /* Total number of parts of the split WIM file, or 1 if the WIM is not
89 /* Number of images in the WIM. */
92 /* Location and size of the WIM's lookup table. */
93 struct resource_entry_disk lookup_table_res_entry;
95 /* Location and size of the WIM's XML data. */
96 struct resource_entry_disk xml_data_res_entry;
98 /* Location and size of metadata resource for the bootable image of the
99 * WIM, or all zeroes if no image is bootable. */
100 struct resource_entry_disk boot_metadata_res_entry;
102 /* 1-based index of the bootable image of the WIM, or 0 if no image is
106 /* Location and size of the WIM's integrity table, or all zeroes if the
107 * WIM has no integrity table.
109 * Note the integrity_table_res_entry here is 4-byte aligned even though
110 * it would ordinarily be 8-byte aligned--- hence, the _packed_attribute
111 * on the `struct wim_header_disk' is essential. */
112 struct resource_entry_disk integrity_table_res_entry;
119 /* Header at the very beginning of the WIM file. This is the in-memory
120 * representation and does not include all fields; see `struct wim_header_disk'
121 * for the on-disk structure. */
124 /* Magic characters: either WIM_MAGIC or PWM_MAGIC. */
127 /* Bitwise OR of one or more of the WIM_HDR_FLAG_* defined below. */
130 /* A unique identifier for the WIM file. */
131 u8 guid[WIM_GID_LEN];
133 /* Part number of the WIM file in a spanned set. */
136 /* Total number of parts in a spanned set. */
139 /* Number of images in the WIM file. */
142 /* Location, size, and flags of the lookup table of the WIM. */
143 struct resource_entry lookup_table_res_entry;
145 /* Location, size, and flags for the XML data of the WIM. */
146 struct resource_entry xml_res_entry;
148 /* Location, size, and flags for the boot metadata. This means the
149 * metadata resource for the image specified by boot_idx below. Should
150 * be zeroed out if boot_idx is 0. */
151 struct resource_entry boot_metadata_res_entry;
153 /* The index of the bootable image in the WIM file. If 0, there are no
154 * bootable images available. */
157 /* The location of the optional integrity table used to verify the
158 * integrity WIM. Zeroed out if there is no integrity table.*/
159 struct resource_entry integrity;
162 /* Flags for the `flags' field of the struct wim_header: */
164 /* Reserved for future use */
165 #define WIM_HDR_FLAG_RESERVED 0x00000001
167 /* Files and metadata in the WIM are compressed. */
168 #define WIM_HDR_FLAG_COMPRESSION 0x00000002
170 /* WIM is read-only, so modifications should not be allowed even if the WIM is
171 * writable at the filesystem level. */
172 #define WIM_HDR_FLAG_READONLY 0x00000004
174 /* Resource data specified by images in this WIM may be contained in a different
175 * WIM. Or in other words, this WIM is part of a split WIM. */
176 #define WIM_HDR_FLAG_SPANNED 0x00000008
178 /* The WIM contains resources only; no filesystem metadata. wimlib ignores this
179 * flag, as it looks for resources in all the WIMs anyway. */
180 #define WIM_HDR_FLAG_RESOURCE_ONLY 0x00000010
182 /* The WIM contains metadata only. wimlib ignores this flag. Note that all the
183 * metadata resources for a split WIM should be in the first part. */
184 #define WIM_HDR_FLAG_METADATA_ONLY 0x00000020
186 /* The WIM is currently being written or appended to. */
187 #define WIM_HDR_FLAG_WRITE_IN_PROGRESS 0x00000040
189 /* Reparse point fixup flag. See docs for --rpfix and --norpfix in imagex, or
190 * WIMLIB_ADD_FLAG_{RPFIX,NORPFIX} in wimlib.h. Note that
191 * WIM_HDR_FLAG_RP_FIX is a header flag and just sets the default behavior for
192 * the WIM; it can still be overridder on a per-image basis. But there is no
193 * flag to set the default behavior for a specific image. */
194 #define WIM_HDR_FLAG_RP_FIX 0x00000080
196 /* Unused, reserved flag for another compression type */
197 #define WIM_HDR_FLAG_COMPRESS_RESERVED 0x00010000
199 /* Resources within the WIM are compressed using "XPRESS" compression, which is
200 * a LZ77-based compression algorithm. */
201 #define WIM_HDR_FLAG_COMPRESS_XPRESS 0x00020000
203 /* Resources within the WIM are compressed using "LZX" compression. This is also
204 * a LZ77-based algorithm. */
205 #define WIM_HDR_FLAG_COMPRESS_LZX 0x00040000
207 /* Starting in Windows 8, WIMGAPI can create WIMs using LZMS compression, and
208 * this flag is set on such WIMs. However, an additional undocumented flag
209 * needs to be provided to WIMCreateFile() to create such WIMs, and the version
210 * number in the header of the resulting WIMs is different (3584). None of this
211 * is actually documented, and wimlib does not yet support this compression
213 #define WIM_HDR_FLAG_COMPRESS_LZMS 0x00080000
215 #endif /* _WIMLIB_HEADER_H */