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   1 /*
   2  * header.c
   3  *
   4  * Read, write, or print a WIM header.
   5  */
   6
   7 /*
   8  * Copyright (C) 2012, 2013, 2015 Eric Biggers
   9  *
  10  * This file is free software; you can redistribute it and/or modify it under
  11  * the terms of the GNU Lesser General Public License as published by the Free
  12  * Software Foundation; either version 3 of the License, or (at your option) any
  13  * later version.
  14  *
  15  * This file is distributed in the hope that it will be useful, but WITHOUT
  16  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  17  * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
  18  * details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public License
  21  * along with this file; if not, see http://www.gnu.org/licenses/.
  22  */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #  include "config.h"
  26 #endif
  27
  28 #include <ctype.h>
  29 #include <stdio.h>
  30 #include <string.h>
  31 #include <unistd.h>
  32
  33 #include "wimlib.h"
  34 #include "wimlib/alloca.h"
  35 #include "wimlib/assert.h"
  36 #include "wimlib/endianness.h"
  37 #include "wimlib/error.h"
  38 #include "wimlib/file_io.h"
  39 #include "wimlib/header.h"
  40 #include "wimlib/util.h"
  41 #include "wimlib/wim.h"
  42
  43 /*
  44  * Reads the header from a WIM file.
  45  *
  46  * @wim
  47  *      WIM to read the header from.  @wim->in_fd must be positioned at the
  48  *      beginning of the file.
  49  *
  50  * @hdr
  51  *      Structure to read the header into.
  52  *
  53  * Return values:
  54  *      WIMLIB_ERR_SUCCESS (0)
  55  *      WIMLIB_ERR_IMAGE_COUNT
  56  *      WIMLIB_ERR_INVALID_PART_NUMBER
  57  *      WIMLIB_ERR_NOT_A_WIM_FILE
  58  *      WIMLIB_ERR_READ
  59  *      WIMLIB_ERR_UNEXPECTED_END_OF_FILE
  60  *      WIMLIB_ERR_UNKNOWN_VERSION
  61  */
  62 int
  63 read_wim_header(WIMStruct *wim, struct wim_header *hdr)
  64 {
  65         struct wim_header_disk disk_hdr _aligned_attribute(8);
  66         struct filedes *in_fd = &wim->in_fd;
  67         const tchar *filename = wim->filename;
  68         int ret;
  69         tchar *pipe_str;
  70
  71         wimlib_assert(in_fd->offset == 0);
  72
  73         if (filename == NULL) {
  74                 pipe_str = alloca(40);
  75                 tsprintf(pipe_str, T("[fd %d]"), in_fd->fd);
  76                 filename = pipe_str;
  77         }
  78
  79         BUILD_BUG_ON(sizeof(struct wim_header_disk) != WIM_HEADER_DISK_SIZE);
  80
  81         DEBUG("Reading WIM header from \"%"TS"\"", filename);
  82
  83         ret = full_read(in_fd, &disk_hdr, sizeof(disk_hdr));
  84         if (ret)
  85                 goto read_error;
  86
  87         hdr->magic = le64_to_cpu(disk_hdr.magic);
  88
  89         if (hdr->magic != WIM_MAGIC) {
  90                 if (hdr->magic == PWM_MAGIC) {
  91                         /* Pipable WIM:  Use header at end instead, unless
  92                          * actually reading from a pipe.  */
  93                         if (!in_fd->is_pipe) {
  94                                 ret = WIMLIB_ERR_READ;
  95                                 if (-1 == lseek(in_fd->fd, -WIM_HEADER_DISK_SIZE, SEEK_END))
  96                                         goto read_error;
  97                                 ret = full_read(in_fd, &disk_hdr, sizeof(disk_hdr));
  98                                 if (ret)
  99                                         goto read_error;
 100                         }
 101                 } else {
 102                         ERROR("\"%"TS"\": Invalid magic characters in header", filename);
 103                         return WIMLIB_ERR_NOT_A_WIM_FILE;
 104                 }
 105         }
 106
 107         if (le32_to_cpu(disk_hdr.hdr_size) != sizeof(struct wim_header_disk)) {
 108                 ERROR("\"%"TS"\": Header size is invalid (%u bytes)",
 109                       filename, le32_to_cpu(disk_hdr.hdr_size));
 110                 return WIMLIB_ERR_INVALID_HEADER;
 111         }
 112
 113         hdr->wim_version = le32_to_cpu(disk_hdr.wim_version);
 114         if (hdr->wim_version != WIM_VERSION_DEFAULT &&
 115             hdr->wim_version != WIM_VERSION_SOLID)
 116         {
 117                 ERROR("\"%"TS"\": Unknown WIM version: %u",
 118                       filename, hdr->wim_version);
 119                 return WIMLIB_ERR_UNKNOWN_VERSION;
 120         }
 121
 122         hdr->flags = le32_to_cpu(disk_hdr.wim_flags);
 123         hdr->chunk_size = le32_to_cpu(disk_hdr.chunk_size);
 124         memcpy(hdr->guid, disk_hdr.guid, WIM_GUID_LEN);
 125         hdr->part_number = le16_to_cpu(disk_hdr.part_number);
 126         hdr->total_parts = le16_to_cpu(disk_hdr.total_parts);
 127
 128         if (hdr->total_parts == 0 || hdr->part_number == 0 ||
 129             hdr->part_number > hdr->total_parts)
 130         {
 131                 ERROR("\"%"TS"\": Invalid WIM part number: %hu of %hu",
 132                       filename, hdr->part_number, hdr->total_parts);
 133                 return WIMLIB_ERR_INVALID_PART_NUMBER;
 134         }
 135
 136         hdr->image_count = le32_to_cpu(disk_hdr.image_count);
 137
 138         DEBUG("part_number = %u, total_parts = %u, image_count = %u",
 139               hdr->part_number, hdr->total_parts, hdr->image_count);
 140
 141         if (unlikely(hdr->image_count > MAX_IMAGES)) {
 142                 ERROR("\"%"TS"\": Invalid image count (%u)",
 143                       filename, hdr->image_count);
 144                 return WIMLIB_ERR_IMAGE_COUNT;
 145         }
 146
 147         get_wim_reshdr(&disk_hdr.blob_table_reshdr, &hdr->blob_table_reshdr);
 148         get_wim_reshdr(&disk_hdr.xml_data_reshdr, &hdr->xml_data_reshdr);
 149         get_wim_reshdr(&disk_hdr.boot_metadata_reshdr, &hdr->boot_metadata_reshdr);
 150         hdr->boot_idx = le32_to_cpu(disk_hdr.boot_idx);
 151         get_wim_reshdr(&disk_hdr.integrity_table_reshdr, &hdr->integrity_table_reshdr);
 152         return 0;
 153
 154 read_error:
 155         ERROR_WITH_ERRNO("\"%"TS"\": Error reading header", filename);
 156         return ret;
 157 }
 158
 159 /* Writes the header for a WIM file at the specified offset.  If the offset
 160  * specified is the current one, the position is advanced by the size of the
 161  * header.  */
 162 int
 163 write_wim_header_at_offset(const struct wim_header *hdr, struct filedes *out_fd,
 164                            off_t offset)
 165 {
 166         struct wim_header_disk disk_hdr _aligned_attribute(8);
 167         int ret;
 168
 169         DEBUG("Writing %sWIM header at offset %"PRIu64,
 170               ((hdr->magic == PWM_MAGIC) ? "pipable " : ""),
 171               offset);
 172
 173         disk_hdr.magic = cpu_to_le64(hdr->magic);
 174         disk_hdr.hdr_size = cpu_to_le32(sizeof(struct wim_header_disk));
 175         disk_hdr.wim_version = cpu_to_le32(hdr->wim_version);
 176         disk_hdr.wim_flags = cpu_to_le32(hdr->flags);
 177         if (hdr->flags & WIM_HDR_FLAG_COMPRESSION)
 178                 disk_hdr.chunk_size = cpu_to_le32(hdr->chunk_size);
 179         else
 180                 disk_hdr.chunk_size = 0;
 181         memcpy(disk_hdr.guid, hdr->guid, WIM_GUID_LEN);
 182
 183         disk_hdr.part_number = cpu_to_le16(hdr->part_number);
 184         disk_hdr.total_parts = cpu_to_le16(hdr->total_parts);
 185         disk_hdr.image_count = cpu_to_le32(hdr->image_count);
 186         put_wim_reshdr(&hdr->blob_table_reshdr, &disk_hdr.blob_table_reshdr);
 187         put_wim_reshdr(&hdr->xml_data_reshdr, &disk_hdr.xml_data_reshdr);
 188         put_wim_reshdr(&hdr->boot_metadata_reshdr, &disk_hdr.boot_metadata_reshdr);
 189         disk_hdr.boot_idx = cpu_to_le32(hdr->boot_idx);
 190         put_wim_reshdr(&hdr->integrity_table_reshdr, &disk_hdr.integrity_table_reshdr);
 191         memset(disk_hdr.unused, 0, sizeof(disk_hdr.unused));
 192
 193         if (offset == out_fd->offset)
 194                 ret = full_write(out_fd, &disk_hdr, sizeof(disk_hdr));
 195         else
 196                 ret = full_pwrite(out_fd, &disk_hdr, sizeof(disk_hdr), offset);
 197         if (ret)
 198                 ERROR_WITH_ERRNO("Failed to write WIM header");
 199         return ret;
 200 }
 201
 202 /* Writes the header for a WIM file at the output file descriptor's current
 203  * offset.  */
 204 int
 205 write_wim_header(const struct wim_header *hdr, struct filedes *out_fd)
 206 {
 207         return write_wim_header_at_offset(hdr, out_fd, out_fd->offset);
 208 }
 209
 210 /* Update just the wim_flags field. */
 211 int
 212 write_wim_header_flags(u32 hdr_flags, struct filedes *out_fd)
 213 {
 214         le32 flags = cpu_to_le32(hdr_flags);
 215
 216         return full_pwrite(out_fd, &flags, sizeof(flags),
 217                            offsetof(struct wim_header_disk, wim_flags));
 218 }
 219
 220 void
 221 set_wim_hdr_cflags(enum wimlib_compression_type ctype, struct wim_header *hdr)
 222 {
 223         hdr->flags &= ~(WIM_HDR_FLAG_COMPRESSION |
 224                         WIM_HDR_FLAG_COMPRESS_RESERVED |
 225                         WIM_HDR_FLAG_COMPRESS_XPRESS |
 226                         WIM_HDR_FLAG_COMPRESS_LZX |
 227                         WIM_HDR_FLAG_COMPRESS_LZMS |
 228                         WIM_HDR_FLAG_COMPRESS_XPRESS_2);
 229         switch (ctype) {
 230         case WIMLIB_COMPRESSION_TYPE_NONE:
 231                 return;
 232         case WIMLIB_COMPRESSION_TYPE_XPRESS:
 233                 hdr->flags |= WIM_HDR_FLAG_COMPRESSION | WIM_HDR_FLAG_COMPRESS_XPRESS;
 234                 return;
 235         case WIMLIB_COMPRESSION_TYPE_LZX:
 236                 hdr->flags |= WIM_HDR_FLAG_COMPRESSION | WIM_HDR_FLAG_COMPRESS_LZX;
 237                 return;
 238         case WIMLIB_COMPRESSION_TYPE_LZMS:
 239                 hdr->flags |= WIM_HDR_FLAG_COMPRESSION | WIM_HDR_FLAG_COMPRESS_LZMS;
 240                 return;
 241         }
 242         wimlib_assert(0);
 243 }
 244
 245 /* Initialize the header for a WIM file.  */
 246 void
 247 init_wim_header(struct wim_header *hdr,
 248                 enum wimlib_compression_type ctype, u32 chunk_size)
 249 {
 250         memset(hdr, 0, sizeof(struct wim_header));
 251         hdr->magic = WIM_MAGIC;
 252         if (ctype == WIMLIB_COMPRESSION_TYPE_LZMS)
 253                 hdr->wim_version = WIM_VERSION_SOLID;
 254         else
 255                 hdr->wim_version = WIM_VERSION_DEFAULT;
 256         set_wim_hdr_cflags(ctype, hdr);
 257         hdr->chunk_size = chunk_size;
 258         hdr->total_parts = 1;
 259         hdr->part_number = 1;
 260         randomize_byte_array(hdr->guid, sizeof(hdr->guid));
 261 }
 262
 263 static const struct {
 264         u32 flag;
 265         const char *name;
 266 } hdr_flags[] = {
 267         {WIM_HDR_FLAG_RESERVED,         "RESERVED"},
 268         {WIM_HDR_FLAG_COMPRESSION,      "COMPRESSION"},
 269         {WIM_HDR_FLAG_READONLY,         "READONLY"},
 270         {WIM_HDR_FLAG_SPANNED,          "SPANNED"},
 271         {WIM_HDR_FLAG_RESOURCE_ONLY,    "RESOURCE_ONLY"},
 272         {WIM_HDR_FLAG_METADATA_ONLY,    "METADATA_ONLY"},
 273         {WIM_HDR_FLAG_WRITE_IN_PROGRESS,"WRITE_IN_PROGRESS"},
 274         {WIM_HDR_FLAG_RP_FIX,           "RP_FIX"},
 275         {WIM_HDR_FLAG_COMPRESS_RESERVED,"COMPRESS_RESERVED"},
 276         {WIM_HDR_FLAG_COMPRESS_LZX,     "COMPRESS_LZX"},
 277         {WIM_HDR_FLAG_COMPRESS_XPRESS,  "COMPRESS_XPRESS"},
 278         {WIM_HDR_FLAG_COMPRESS_LZMS,    "COMPRESS_LZMS"},
 279         {WIM_HDR_FLAG_COMPRESS_XPRESS_2,"COMPRESS_XPRESS_2"},
 280 };
 281
 282 /* API function documented in wimlib.h  */
 283 WIMLIBAPI void
 284 wimlib_print_header(const WIMStruct *wim)
 285 {
 286         const struct wim_header *hdr = &wim->hdr;
 287
 288         tprintf(T("Magic Characters            = "));
 289         for (int i = 0; i < sizeof(hdr->magic); i++) {
 290                 tchar c = (u8)(hdr->magic >> ((8 * i)));
 291                 if (istalpha(c))
 292                         tputchar(c);
 293                 else
 294                         tprintf(T("\\%o"), c);
 295         }
 296         tputchar(T('\n'));
 297         tprintf(T("Header Size                 = %u\n"), WIM_HEADER_DISK_SIZE);
 298         tprintf(T("Version                     = 0x%x\n"), hdr->wim_version);
 299
 300         tprintf(T("Flags                       = 0x%x\n"), hdr->flags);
 301         for (size_t i = 0; i < ARRAY_LEN(hdr_flags); i++)
 302                 if (hdr_flags[i].flag & hdr->flags)
 303                         tprintf(T("    WIM_HDR_FLAG_%s is set\n"), hdr_flags[i].name);
 304
 305         tprintf(T("Chunk Size                  = %u\n"), hdr->chunk_size);
 306         tfputs (T("GUID                        = "), stdout);
 307         print_byte_field(hdr->guid, WIM_GUID_LEN, stdout);
 308         tputchar(T('\n'));
 309         tprintf(T("Part Number                 = %hu\n"), hdr->part_number);
 310         tprintf(T("Total Parts                 = %hu\n"), hdr->total_parts);
 311         tprintf(T("Image Count                 = %u\n"), hdr->image_count);
 312         tprintf(T("Blob Table Size             = %"PRIu64"\n"),
 313                                 (u64)hdr->blob_table_reshdr.size_in_wim);
 314         tprintf(T("Blob Table Flags            = 0x%hhx\n"),
 315                                 (u8)hdr->blob_table_reshdr.flags);
 316         tprintf(T("Blob Table Offset           = %"PRIu64"\n"),
 317                                 hdr->blob_table_reshdr.offset_in_wim);
 318         tprintf(T("Blob Table Original_size    = %"PRIu64"\n"),
 319                                 hdr->blob_table_reshdr.uncompressed_size);
 320         tprintf(T("XML Data Size               = %"PRIu64"\n"),
 321                                 (u64)hdr->xml_data_reshdr.size_in_wim);
 322         tprintf(T("XML Data Flags              = 0x%hhx\n"),
 323                                 (u8)hdr->xml_data_reshdr.flags);
 324         tprintf(T("XML Data Offset             = %"PRIu64"\n"),
 325                                 hdr->xml_data_reshdr.offset_in_wim);
 326         tprintf(T("XML Data Original Size      = %"PRIu64"\n"),
 327                                 hdr->xml_data_reshdr.uncompressed_size);
 328         tprintf(T("Boot Metadata Size          = %"PRIu64"\n"),
 329                                 (u64)hdr->boot_metadata_reshdr.size_in_wim);
 330         tprintf(T("Boot Metadata Flags         = 0x%hhx\n"),
 331                                 (u8)hdr->boot_metadata_reshdr.flags);
 332         tprintf(T("Boot Metadata Offset        = %"PRIu64"\n"),
 333                                 hdr->boot_metadata_reshdr.offset_in_wim);
 334         tprintf(T("Boot Metadata Original Size = %"PRIu64"\n"),
 335                                 hdr->boot_metadata_reshdr.uncompressed_size);
 336         tprintf(T("Boot Index                  = %u\n"), hdr->boot_idx);
 337         tprintf(T("Integrity Size              = %"PRIu64"\n"),
 338                                 (u64)hdr->integrity_table_reshdr.size_in_wim);
 339         tprintf(T("Integrity Flags             = 0x%hhx\n"),
 340                                 (u8)hdr->integrity_table_reshdr.flags);
 341         tprintf(T("Integrity Offset            = %"PRIu64"\n"),
 342                                 hdr->integrity_table_reshdr.offset_in_wim);
 343         tprintf(T("Integrity Original_size     = %"PRIu64"\n"),
 344                                 hdr->integrity_table_reshdr.uncompressed_size);
 345 }