X-Git-Url: https://wimlib.net/git/?a=blobdiff_plain;f=include%2Fwimlib%2Fheader.h;h=2841b827ca1bfb9eb2620750a8f99ca9ea594afa;hb=5c0846b71891c0c088de4f9ef4cc6ab545f5b64e;hp=637a4fef9f807f40a1c21dd63a05e36d950cd78e;hpb=3d84c998673ba7acf82ec5c26769a41e28a2cc7b;p=wimlib diff --git a/include/wimlib/header.h b/include/wimlib/header.h index 637a4fef..2841b827 100644 --- a/include/wimlib/header.h +++ b/include/wimlib/header.h @@ -11,80 +11,122 @@ /* Length of the WIM header on disk. */ #define WIM_HEADER_DISK_SIZE 208 -/* Compressed resources in the WIM are divided into separated compressed chunks - * of this size. This value is unfortunately not configurable (at least when - * compatibility with Microsoft's software is desired). */ -#define WIM_CHUNK_SIZE 32768 - -/* Version of the WIM file. There is an older version (used for prerelease - * versions of Windows Vista), but wimlib doesn't support it. The differences - * between the versions are undocumented. */ -#define WIM_VERSION 0x10d00 - -/* WIM magic characters, translated to a single 64-bit little endian number. */ -#define WIM_MAGIC \ - cpu_to_le64(((u64)'M' << 0) | \ - ((u64)'S' << 8) | \ - ((u64)'W' << 16) | \ - ((u64)'I' << 24) | \ - ((u64)'M' << 32) | \ - ((u64)'\0' << 40) | \ - ((u64)'\0' << 48) | \ - ((u64)'\0' << 54)) - -/* wimlib pipable WIM magic characters, translated to a single 64-bit little - * endian number. */ -#define PWM_MAGIC \ - cpu_to_le64(((u64)'W' << 0) | \ - ((u64)'L' << 8) | \ - ((u64)'P' << 16) | \ - ((u64)'W' << 24) | \ - ((u64)'M' << 32) | \ - ((u64)'\0' << 40) | \ - ((u64)'\0' << 48) | \ - ((u64)'\0' << 54)) - -/* Header at the very beginning of the WIM file. This is the in-memory - * representation and does not include all fields; see `struct wim_header_disk' - * for the on-disk structure. */ -struct wim_header { - - /* Magic characters: either WIM_MAGIC or PWM_MAGIC. */ +/* Default WIM version number. Streams are always compressed independently. */ +#define WIM_VERSION_DEFAULT 0x10d00 + +/* Version number used for WIMs that allow multiple streams packed into one + * resource (WIM_RESHDR_FLAG_PACKED_STREAMS). New as of Windows 8 WIMGAPI; used + * for the Windows 8 web downloader, but yet not yet properly documented by + * Microsoft. This WIM format also allows a new compression format (LZMS). */ +#define WIM_VERSION_PACKED_STREAMS 0xe00 + +/* Note: there is another WIM version from Vista pre-releases, but it is not + * supported by wimlib. */ + +/* WIM magic characters, translated to a single 64-bit number. */ +#define WIM_MAGIC \ + (((u64)'M' << 0) | \ + ((u64)'S' << 8) | \ + ((u64)'W' << 16) | \ + ((u64)'I' << 24) | \ + ((u64)'M' << 32) | \ + ((u64)'\0' << 40) | \ + ((u64)'\0' << 48) | \ + ((u64)'\0' << 54)) + +/* wimlib pipable WIM magic characters, translated to a single 64-bit number. + * */ +#define PWM_MAGIC \ + (((u64)'W' << 0) | \ + ((u64)'L' << 8) | \ + ((u64)'P' << 16) | \ + ((u64)'W' << 24) | \ + ((u64)'M' << 32) | \ + ((u64)'\0' << 40) | \ + ((u64)'\0' << 48) | \ + ((u64)'\0' << 54)) + +/* On-disk format of the WIM header. */ +struct wim_header_disk { + + /* +0x00: Magic characters "MSWIM\0\0\0". */ le64 magic; - /* Bitwise OR of one or more of the WIM_HDR_FLAG_* defined below. */ - u32 flags; + /* +0x08: Size of the WIM header, in bytes; WIM_HEADER_DISK_SIZE + * expected (currently the only supported value). */ + u32 hdr_size; + + /* +0x0c: Version of the WIM file. Recognized values are the + * WIM_VERSION_* constants from above. */ + u32 wim_version; + + /* +0x10: Flags for the WIM file (WIM_HDR_FLAG_*). */ + u32 wim_flags; - /* A unique identifier for the WIM file. */ + /* +0x14: Uncompressed chunk size for compressed resources in the WIM + * other than packed resources, or 0 if the WIM is uncompressed. */ + u32 chunk_size; + + /* +0x18: Globally unique identifier for the WIM file. Basically a + * bunch of random bytes. */ u8 guid[WIM_GID_LEN]; - /* Part number of the WIM file in a spanned set. */ + /* +0x28: Number of this WIM part in the split WIM file, indexed from 1, + * or 1 if the WIM is not split. */ u16 part_number; - /* Total number of parts in a spanned set. */ + /* +0x2a: Total number of parts of the split WIM file, or 1 if the WIM + * is not split. */ u16 total_parts; - /* Number of images in the WIM file. */ + /* +0x2c: Number of images in the WIM. */ u32 image_count; - /* Location, size, and flags of the lookup table of the WIM. */ - struct resource_entry lookup_table_res_entry; + /* +0x30: Location and size of the WIM's lookup table. */ + struct wim_reshdr_disk lookup_table_reshdr; - /* Location, size, and flags for the XML data of the WIM. */ - struct resource_entry xml_res_entry; + /* +0x48: Location and size of the WIM's XML data. */ + struct wim_reshdr_disk xml_data_reshdr; - /* Location, size, and flags for the boot metadata. This means the - * metadata resource for the image specified by boot_idx below. Should - * be zeroed out if boot_idx is 0. */ - struct resource_entry boot_metadata_res_entry; + /* +0x60: Location and size of metadata resource for the bootable image + * of the WIM, or all zeroes if no image is bootable. */ + struct wim_reshdr_disk boot_metadata_reshdr; - /* The index of the bootable image in the WIM file. If 0, there are no - * bootable images available. */ + /* +0x78: 1-based index of the bootable image of the WIM, or 0 if no + * image is bootable. */ u32 boot_idx; - /* The location of the optional integrity table used to verify the - * integrity WIM. Zeroed out if there is no integrity table.*/ - struct resource_entry integrity; + /* +0x7c: Location and size of the WIM's integrity table, or all zeroes + * if the WIM has no integrity table. + * + * Note the integrity_table_reshdr here is 4-byte aligned even though it + * would ordinarily be 8-byte aligned--- hence, the _packed_attribute on + * this structure is essential. */ + struct wim_reshdr_disk integrity_table_reshdr; + + /* +0x94: Unused bytes. */ + u8 unused[60]; + + /* +0xd0 (208) */ +} _packed_attribute; + + +/* In-memory representation of a WIM header. See `struct wim_header_disk' for + * field descriptions. */ +struct wim_header { + u64 magic; + u32 wim_version; + u32 flags; + u32 chunk_size; + u8 guid[WIM_GID_LEN]; + u16 part_number; + u16 total_parts; + u32 image_count; + struct wim_reshdr lookup_table_reshdr; + struct wim_reshdr xml_data_reshdr; + struct wim_reshdr boot_metadata_reshdr; + u32 boot_idx; + struct wim_reshdr integrity_table_reshdr; }; /* Flags for the `flags' field of the struct wim_header: */ @@ -125,11 +167,19 @@ struct wim_header { #define WIM_HDR_FLAG_COMPRESS_RESERVED 0x00010000 /* Resources within the WIM are compressed using "XPRESS" compression, which is - * a LZ77-based compression algorithm. */ + * a LZ77-based compression algorithm. */ #define WIM_HDR_FLAG_COMPRESS_XPRESS 0x00020000 /* Resources within the WIM are compressed using "LZX" compression. This is also * a LZ77-based algorithm. */ #define WIM_HDR_FLAG_COMPRESS_LZX 0x00040000 +/* Starting in Windows 8, WIMGAPI can create WIMs using LZMS compression, and + * this flag is set on such WIMs. However, an additional undocumented flag + * needs to be provided to WIMCreateFile() to create such WIMs, and the version + * number in the header of the resulting WIMs is different (3584). None of this + * is actually documented, and wimlib does not yet support this compression + * format. */ +#define WIM_HDR_FLAG_COMPRESS_LZMS 0x00080000 + #endif /* _WIMLIB_HEADER_H */