X-Git-Url: https://wimlib.net/git/?a=blobdiff_plain;f=src%2Fresource.c;h=59c1d9c6cfe019b26db160e7ad57040ca5f8adcf;hb=bf9f9a8533a6f216068bdf61cafb1681ed1b7e1c;hp=600bf5ba1321bb772f4d788ccfe33aad456c661b;hpb=885632f08c75c1d7bb5d25436231c78f6ad7e0c0;p=wimlib diff --git a/src/resource.c b/src/resource.c index 600bf5ba..59c1d9c6 100644 --- a/src/resource.c +++ b/src/resource.c @@ -2,33 +2,45 @@ * resource.c * * Read uncompressed and compressed metadata and file resources. - * + */ + +/* * Copyright (C) 2010 Carl Thijssen * Copyright (C) 2012 Eric Biggers * - * wimlib - Library for working with WIM files + * This file is part of wimlib, a library for working with WIM files. * - * 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. + * wimlib 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. + * wimlib 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 + * You should have received a copy of the GNU Lesser General Public License + * along with wimlib; if not, see http://www.gnu.org/licenses/. */ #include "wimlib_internal.h" +#include "lookup_table.h" #include "io.h" #include "lzx.h" #include "xpress.h" +#include "sha1.h" #include "dentry.h" +#include "config.h" #include #include +#include + +#ifdef WITH_NTFS_3G +#include +#include +#include +#endif /* * Reads all or part of a compressed resource into an in-memory buffer. @@ -54,15 +66,13 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, u64 len, u64 offset, u8 contents_ret[]) { - DEBUG2("comp size = %"PRIu64", " - "uncomp size = %"PRIu64", " - "res offset = %"PRIu64"\n", - resource_compressed_size, - resource_uncompressed_size, - resource_offset); - DEBUG2("resource_ctype = %s, len = %"PRIu64", offset = %"PRIu64"\n", - wimlib_get_compression_type_string(resource_ctype), - len, offset); + DEBUG2("comp size = %"PRIu64", uncomp size = %"PRIu64", " + "res offset = %"PRIu64"", + resource_compressed_size, + resource_uncompressed_size, + resource_offset); + DEBUG2("resource_ctype = %s, len = %"PRIu64", offset = %"PRIu64"", + wimlib_get_compression_type_string(resource_ctype), len, offset); /* Trivial case */ if (len == 0) return 0; @@ -152,10 +162,9 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, u64 file_offset_of_needed_chunk_entries = resource_offset + start_table_idx * chunk_entry_size; if (fseeko(fp, file_offset_of_needed_chunk_entries, SEEK_SET) != 0) { - ERROR("Failed to seek to byte %"PRIu64" " - "to read chunk table of compressed " - "resource: %m\n", - file_offset_of_needed_chunk_entries); + ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" to read " + "chunk table of compressed resource", + file_offset_of_needed_chunk_entries); return WIMLIB_ERR_READ; } @@ -190,10 +199,9 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, u64 file_offset_of_first_needed_chunk = resource_offset + chunk_table_size + chunk_offsets[0]; if (fseeko(fp, file_offset_of_first_needed_chunk, SEEK_SET) != 0) { - ERROR("Failed to seek to byte %"PRIu64" " - "to read first chunk of compressed " - "resource: %m\n", - file_offset_of_first_needed_chunk); + ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" to read " + "first chunk of compressed resource", + file_offset_of_first_needed_chunk); return WIMLIB_ERR_READ; } @@ -213,8 +221,8 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, /* Decompress all the chunks. */ for (u64 i = start_chunk; i <= end_chunk; i++) { - DEBUG2("Chunk %"PRIu64" (start %"PRIu64", end %"PRIu64")\n", - i, start_chunk, end_chunk); + DEBUG2("Chunk %"PRIu64" (start %"PRIu64", end %"PRIu64").", + i, start_chunk, end_chunk); /* Calculate the sizes of the compressed chunk and of the * uncompressed chunk. */ @@ -249,8 +257,9 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, uncompressed_chunk_size = WIM_CHUNK_SIZE; } - DEBUG2("compressed_chunk_size = %u, uncompressed_chunk_size = %u\n", - compressed_chunk_size, uncompressed_chunk_size); + DEBUG2("compressed_chunk_size = %u, " + "uncompressed_chunk_size = %u", + compressed_chunk_size, uncompressed_chunk_size); /* Figure out how much of this chunk we actually need to read */ @@ -269,9 +278,9 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, bool is_partial_chunk = (partial_chunk_size != uncompressed_chunk_size); - DEBUG2("start_offset = %u, end_offset = %u\n", start_offset, + DEBUG2("start_offset = %u, end_offset = %u", start_offset, end_offset); - DEBUG2("partial_chunk_size = %u\n", partial_chunk_size); + DEBUG2("partial_chunk_size = %u", partial_chunk_size); /* This is undocumented, but chunks can be uncompressed. This * appears to always be the case when the compressed chunk size @@ -281,8 +290,8 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, if (start_offset != 0) { if (fseeko(fp, start_offset, SEEK_CUR) != 0) { - ERROR("Uncompressed partial chunk " - "fseek() error: %m\n"); + ERROR_WITH_ERRNO("Uncompressed partial " + "chunk fseek() error"); return WIMLIB_ERR_READ; } } @@ -312,7 +321,6 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, memcpy(out_p, uncompressed_buf + start_offset, partial_chunk_size); } else { - DEBUG2("out_p = %p\n"); ret = decompress(compressed_buf, compressed_chunk_size, out_p, @@ -331,136 +339,39 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, err: if (feof(fp)) - ERROR("Unexpected EOF in compressed file resource\n"); + ERROR("Unexpected EOF in compressed file resource"); else - ERROR("Error reading compressed file resource: %m\n"); + ERROR_WITH_ERRNO("Error reading compressed file resource"); return WIMLIB_ERR_READ; } /* * Reads uncompressed data from an open file stream. */ -int read_uncompressed_resource(FILE *fp, u64 offset, u64 len, - u8 contents_ret[]) +int read_uncompressed_resource(FILE *fp, u64 offset, u64 len, + u8 contents_ret[]) { if (fseeko(fp, offset, SEEK_SET) != 0) { ERROR("Failed to seek to byte %"PRIu64" of input file " - "to read uncompressed resource " - "(len = %"PRIu64")!\n", offset, len); + "to read uncompressed resource (len = %"PRIu64")", + offset, len); return WIMLIB_ERR_READ; } if (fread(contents_ret, 1, len, fp) != len) { if (feof(fp)) { - ERROR("Unexpected EOF in uncompressed file resource!\n"); + ERROR("Unexpected EOF in uncompressed file resource"); } else { ERROR("Failed to read %"PRIu64" bytes from " - "uncompressed resource at offset " - "%"PRIu64"\n", len, offset); + "uncompressed resource at offset %"PRIu64, + len, offset); } return WIMLIB_ERR_READ; } return 0; } -/* - * Reads a WIM resource. - * - * @fp: The FILE* for the WIM file. - * @resource_size: The compressed size of the resource. - * @resource_original_size: The uncompressed size of the resource. - * @resource_offset: The offset of the resource in the stream @fp. - * @resource_ctype: The compression type of the resource. - * (WIM_COMPRESSION_TYPE_*) - * @len: How many bytes of the resource should be read. - * @offset: The offset within the resource at which the read - * will occur. - * - * To read the whole file resource, specify offset = - * 0 and len = resource_original_size, or call - * read_full_resource(). - * - * @contents_ret: An array, that must have length at least @len, - * into which the uncompressed contents of - * the file resource starting at @offset and - * continuing for @len bytes will be written. - * - * @return: Zero on success, nonzero on failure. Failure may be due to - * being unable to read the data from the WIM file at the - * specified length and offset, or it may be due to the - * compressed data (if the data is compressed) being - * invalid. - */ -int read_resource(FILE *fp, u64 resource_size, u64 resource_original_size, - u64 resource_offset, int resource_ctype, u64 len, - u64 offset, void *contents_ret) -{ - if (resource_ctype == WIM_COMPRESSION_TYPE_NONE) { - if (resource_size != resource_original_size) { - ERROR("Resource with original size %"PRIu64" " - "bytes is marked as uncompressed, \n", - resource_original_size); - ERROR(" but its actual size is %"PRIu64" " - "bytes!\n", - resource_size); - return WIMLIB_ERR_INVALID_RESOURCE_SIZE; - } - return read_uncompressed_resource(fp, - resource_offset + offset, - len, contents_ret); - } else { - return read_compressed_resource(fp, resource_size, - resource_original_size, resource_offset, - resource_ctype, len, offset, contents_ret); - } -} - -/* - * Extracts the first @size bytes file resource specified by @entry to the open - * file @fd. Returns nonzero on error. - * - * XXX - * This function is somewhat redundant with uncompress_resource(). The - * main difference is that this function writes to a file descriptor using - * low-level calls to write() rather than to a FILE* with fwrite(); also this - * function allows only up to @size bytes to be extracted. - */ -int extract_resource_to_fd(WIMStruct *w, const struct resource_entry *entry, - int fd, u64 size) -{ - u64 num_chunks; - u64 n; - u8 buf[min(size, WIM_CHUNK_SIZE)]; - int res_ctype; - u64 offset; - u64 i; - int ret; - errno = 0; - - num_chunks = (size + WIM_CHUNK_SIZE - 1) / WIM_CHUNK_SIZE; - n = WIM_CHUNK_SIZE; - res_ctype = wim_resource_compression_type(w, entry); - offset = 0; - for (i = 0; i < num_chunks; i++) { - if (i == num_chunks - 1) { - n = size % WIM_CHUNK_SIZE; - if (n == 0) { - n = WIM_CHUNK_SIZE; - } - } - - ret = read_resource(w->fp, entry->size, entry->original_size, - entry->offset, res_ctype, n, offset, buf); - if (ret != 0) - return ret; - - if (full_write(fd, buf, n) != n) - return WIMLIB_ERR_WRITE; - offset += n; - } - return ret; -} /* Reads the contents of a struct resource_entry, as represented in the on-disk * format, from the memory pointed to by @p, and fills in the fields of @entry. @@ -491,18 +402,692 @@ u8 *put_resource_entry(u8 *p, const struct resource_entry *entry) return p; } -/* Given the compression type for the WIM file as a whole as the flags field of - * a resource entry, returns the compression type for that resource entry. */ -int resource_compression_type(int wim_ctype, int reshdr_flags) +/* + * Reads some data from the resource corresponding to a WIM lookup table entry. + * + * @lte: The WIM lookup table entry for the resource. + * @buf: Buffer into which to write the data. + * @size: Number of bytes to read. + * @offset: Offset at which to start reading the resource. + * @raw: If %true, compressed data is read literally rather than being + * decompressed first. + * + * Returns zero on success, nonzero on failure. + */ +int read_wim_resource(const struct lookup_table_entry *lte, u8 buf[], + size_t size, u64 offset, bool raw) { - if (wim_ctype == WIM_COMPRESSION_TYPE_NONE) { - return WIM_COMPRESSION_TYPE_NONE; - } else { - if (reshdr_flags & WIM_RESHDR_FLAG_COMPRESSED) - return wim_ctype; + /* We shouldn't be allowing read over-runs in any part of the library. + * */ + if (raw) + wimlib_assert(offset + size <= lte->resource_entry.size); + else + wimlib_assert(offset + size <= lte->resource_entry.original_size); + + int ctype; + int ret; + FILE *fp; + switch (lte->resource_location) { + case RESOURCE_IN_WIM: + /* The resource is in a WIM file, and its WIMStruct is given by + * the lte->wim member. The resource may be either compressed + * or uncompressed. */ + wimlib_assert(lte->wim); + wimlib_assert(lte->wim->fp); + ctype = wim_resource_compression_type(lte); + + wimlib_assert(ctype != WIM_COMPRESSION_TYPE_NONE || + (lte->resource_entry.original_size == + lte->resource_entry.size)); + + if (raw || ctype == WIM_COMPRESSION_TYPE_NONE) + return read_uncompressed_resource(lte->wim->fp, + lte->resource_entry.offset + offset, + size, buf); else - return WIM_COMPRESSION_TYPE_NONE; + return read_compressed_resource(lte->wim->fp, + lte->resource_entry.size, + lte->resource_entry.original_size, + lte->resource_entry.offset, + ctype, size, offset, buf); + break; + case RESOURCE_IN_STAGING_FILE: + case RESOURCE_IN_FILE_ON_DISK: + /* The resource is in some file on the external filesystem and + * needs to be read uncompressed */ + wimlib_assert(lte->file_on_disk); + wimlib_assert(<e->file_on_disk == <e->staging_file_name); + /* Use existing file pointer if available; otherwise open one + * temporarily */ + if (lte->file_on_disk_fp) { + fp = lte->file_on_disk_fp; + } else { + fp = fopen(lte->file_on_disk, "rb"); + if (!fp) { + ERROR_WITH_ERRNO("Failed to open the file " + "`%s'", lte->file_on_disk); + return WIMLIB_ERR_OPEN; + } + } + ret = read_uncompressed_resource(fp, offset, size, buf); + if (fp != lte->file_on_disk_fp) + fclose(fp); + return ret; + break; + case RESOURCE_IN_ATTACHED_BUFFER: + /* The resource is directly attached uncompressed in an + * in-memory buffer. */ + wimlib_assert(lte->attached_buffer); + memcpy(buf, lte->attached_buffer + offset, size); + return 0; + break; +#ifdef WITH_NTFS_3G + case RESOURCE_IN_NTFS_VOLUME: + wimlib_assert(lte->ntfs_loc); + if (lte->attr) { + u64 adjusted_offset; + if (lte->ntfs_loc->is_reparse_point) + adjusted_offset = offset + 8; + else + adjusted_offset = offset; + if (ntfs_attr_pread(lte->attr, offset, size, buf) == size) { + return 0; + } else { + ERROR_WITH_ERRNO("Error reading NTFS attribute " + "at `%s'", + lte->ntfs_loc->path_utf8); + return WIMLIB_ERR_NTFS_3G; + } + } else { + wimlib_assert(0); + } + break; +#endif + default: + assert(0); + } +} + +/* + * Reads all the data from the resource corresponding to a WIM lookup table + * entry. + * + * @lte: The WIM lookup table entry for the resource. + * @buf: Buffer into which to write the data. It must be at least + * wim_resource_size(lte) bytes long. + * + * Returns 0 on success; nonzero on failure. + */ +int read_full_wim_resource(const struct lookup_table_entry *lte, u8 buf[]) +{ + return read_wim_resource(lte, buf, wim_resource_size(lte), 0, false); +} + +/* Chunk table that's located at the beginning of each compressed resource in + * the WIM. (This is not the on-disk format; the on-disk format just has an + * array of offsets.) */ +struct chunk_table { + off_t file_offset; + u64 num_chunks; + u64 original_resource_size; + u64 bytes_per_chunk_entry; + u64 table_disk_size; + u64 cur_offset; + u64 *cur_offset_p; + u64 offsets[0]; +}; + +/* + * Allocates and initializes a chunk table, and reserves space for it in the + * output file. + */ +static int +begin_wim_resource_chunk_tab(const struct lookup_table_entry *lte, + FILE *out_fp, + off_t file_offset, + struct chunk_table **chunk_tab_ret) +{ + u64 size = wim_resource_size(lte); + u64 num_chunks = (size + WIM_CHUNK_SIZE - 1) / WIM_CHUNK_SIZE; + struct chunk_table *chunk_tab = MALLOC(sizeof(struct chunk_table) + + num_chunks * sizeof(u64)); + int ret = 0; + + wimlib_assert(size != 0); + + if (!chunk_tab) { + ERROR("Failed to allocate chunk table for %"PRIu64" byte " + "resource", size); + ret = WIMLIB_ERR_NOMEM; + goto out; + } + chunk_tab->file_offset = file_offset; + chunk_tab->num_chunks = num_chunks; + chunk_tab->original_resource_size = size; + chunk_tab->bytes_per_chunk_entry = (size >= (1ULL << 32)) ? 8 : 4; + chunk_tab->table_disk_size = chunk_tab->bytes_per_chunk_entry * + (num_chunks - 1); + chunk_tab->cur_offset = 0; + chunk_tab->cur_offset_p = chunk_tab->offsets; + + if (fwrite(chunk_tab, 1, chunk_tab->table_disk_size, out_fp) != + chunk_tab->table_disk_size) { + ERROR_WITH_ERRNO("Failed to write chunk table in compressed " + "file resource"); + ret = WIMLIB_ERR_WRITE; + goto out; + } + + *chunk_tab_ret = chunk_tab; +out: + return ret; +} + +/* + * Compresses a chunk of a WIM resource. + * + * @chunk: Uncompressed data of the chunk. + * @chunk_size: Size of the uncompressed chunk in bytes. + * @compressed_chunk: Pointer to output buffer of size at least + * (@chunk_size - 1) bytes. + * @compressed_chunk_len_ret: Pointer to an unsigned int into which the size + * of the compressed chunk will be + * returned. + * @ctype: Type of compression to use. Must be WIM_COMPRESSION_TYPE_LZX + * or WIM_COMPRESSION_TYPE_XPRESS. + * + * Returns zero if compressed succeeded, and nonzero if the chunk could not be + * compressed to any smaller than @chunk_size. This function cannot fail for + * any other reasons. + */ +static int compress_chunk(const u8 chunk[], unsigned chunk_size, + u8 compressed_chunk[], + unsigned *compressed_chunk_len_ret, + int ctype) +{ + int (*compress)(const void *, unsigned, void *, unsigned *); + switch (ctype) { + case WIM_COMPRESSION_TYPE_LZX: + compress = lzx_compress; + break; + case WIM_COMPRESSION_TYPE_XPRESS: + compress = xpress_compress; + break; + default: + wimlib_assert(0); + break; + } + return (*compress)(chunk, chunk_size, compressed_chunk, + compressed_chunk_len_ret); +} + +/* + * Writes a chunk of a WIM resource to an output file. + * + * @chunk: Uncompressed data of the chunk. + * @chunk_size: Size of the chunk (<= WIM_CHUNK_SIZE) + * @out_fp: FILE * to write tho chunk to. + * @out_ctype: Compression type to use when writing the chunk (ignored if no + * chunk table provided) + * @chunk_tab: Pointer to chunk table being created. It is updated with the + * offset of the chunk we write. + * + * Returns 0 on success; nonzero on failure. + */ +static int write_wim_resource_chunk(const u8 chunk[], unsigned chunk_size, + FILE *out_fp, int out_ctype, + struct chunk_table *chunk_tab) +{ + const u8 *out_chunk; + unsigned out_chunk_size; + + wimlib_assert(chunk_size <= WIM_CHUNK_SIZE); + + if (!chunk_tab) { + out_chunk = chunk; + out_chunk_size = chunk_size; + } else { + u8 *compressed_chunk = alloca(chunk_size); + int ret; + + ret = compress_chunk(chunk, chunk_size, compressed_chunk, + &out_chunk_size, out_ctype); + if (ret == 0) { + out_chunk = compressed_chunk; + } else { + out_chunk = chunk; + out_chunk_size = chunk_size; + } + *chunk_tab->cur_offset_p++ = chunk_tab->cur_offset; + chunk_tab->cur_offset += out_chunk_size; + } + + if (fwrite(out_chunk, 1, out_chunk_size, out_fp) != out_chunk_size) { + ERROR_WITH_ERRNO("Failed to write WIM resource chunk"); + return WIMLIB_ERR_WRITE; + } + return 0; +} + +/* + * Finishes a WIM chunk tale and writes it to the output file at the correct + * offset. + * + * The final size of the full compressed resource is returned in the + * @compressed_size_p. + */ +static int +finish_wim_resource_chunk_tab(struct chunk_table *chunk_tab, + FILE *out_fp, u64 *compressed_size_p) +{ + size_t bytes_written; + if (fseeko(out_fp, chunk_tab->file_offset, SEEK_SET) != 0) { + ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" of output " + "WIM file", chunk_tab->file_offset); + return WIMLIB_ERR_WRITE; + } + + if (chunk_tab->bytes_per_chunk_entry == 8) { + array_to_le64(chunk_tab->offsets, chunk_tab->num_chunks); + } else { + for (u64 i = 0; i < chunk_tab->num_chunks; i++) + ((u32*)chunk_tab->offsets)[i] = + to_le32(chunk_tab->offsets[i]); + } + bytes_written = fwrite((u8*)chunk_tab->offsets + + chunk_tab->bytes_per_chunk_entry, + 1, chunk_tab->table_disk_size, out_fp); + if (bytes_written != chunk_tab->table_disk_size) { + ERROR_WITH_ERRNO("Failed to write chunk table in compressed " + "file resource"); + return WIMLIB_ERR_WRITE; + } + if (fseeko(out_fp, 0, SEEK_END) != 0) { + ERROR_WITH_ERRNO("Failed to seek to end of output WIM file"); + return WIMLIB_ERR_WRITE; + } + *compressed_size_p = chunk_tab->cur_offset + chunk_tab->table_disk_size; + return 0; +} + +/* + * Writes a WIM resource to a FILE * opened for writing. The resource may be + * written uncompressed or compressed depending on the @out_ctype parameter. + * + * If by chance the resource compresses to more than the original size (this may + * happen with random data or files than are pre-compressed), the resource is + * instead written uncompressed (and this is reflected in the @out_res_entry by + * removing the WIM_RESHDR_FLAG_COMPRESSED flag). + * + * @lte: The lookup table entry for the WIM resource. + * @out_fp: The FILE * to write the resource to. + * @out_ctype: The compression type of the resource to write. Note: if this is + * the same as the compression type of the WIM resource we + * need to read, we simply copy the data (i.e. we do not + * uncompress it, then compress it again). + * @out_res_entry: If non-NULL, a resource entry that is filled in with the + * offset, original size, compressed size, and compression flag + * of the output resource. + * + * Returns 0 on success; nonzero on failure. + */ +static int write_wim_resource(struct lookup_table_entry *lte, + FILE *out_fp, int out_ctype, + struct resource_entry *out_res_entry) +{ + u64 bytes_remaining; + u64 original_size; + u64 old_compressed_size; + u64 new_compressed_size; + u64 offset = 0; + int ret = 0; + struct chunk_table *chunk_tab = NULL; + bool raw; + off_t file_offset; +#ifdef WITH_NTFS_3G + ntfs_inode *ni = NULL; +#endif + + wimlib_assert(lte); + + /* Original size of the resource */ + original_size = wim_resource_size(lte); + + /* Compressed size of the resource (as it exists now) */ + old_compressed_size = wim_resource_compressed_size(lte); + + /* Current offset in output file */ + file_offset = ftello(out_fp); + if (file_offset == -1) { + ERROR_WITH_ERRNO("Failed to get offset in output " + "stream"); + return WIMLIB_ERR_WRITE; } + + /* Are the compression types the same? If so, do a raw copy (copy + * without decompressing and recompressing the data). */ + raw = (wim_resource_compression_type(lte) == out_ctype + && out_ctype != WIM_COMPRESSION_TYPE_NONE); + if (raw) + bytes_remaining = old_compressed_size; + else + bytes_remaining = original_size; + + /* Empty resource; nothing needs to be done, so just return success. */ + if (bytes_remaining == 0) + return 0; + + /* Buffer for reading chunks for the resource */ + u8 buf[min(WIM_CHUNK_SIZE, bytes_remaining)]; + + /* If we are writing a compressed resource and not doing a raw copy, we + * need to initialize the chunk table */ + if (out_ctype != WIM_COMPRESSION_TYPE_NONE && !raw) { + ret = begin_wim_resource_chunk_tab(lte, out_fp, file_offset, + &chunk_tab); + if (ret != 0) + goto out; + } + + /* If the WIM resource is in an external file, open a FILE * to it so we + * don't have to open a temporary one in read_wim_resource() for each + * chunk. */ + if (lte->resource_location == RESOURCE_IN_FILE_ON_DISK + && !lte->file_on_disk_fp) + { + wimlib_assert(lte->file_on_disk); + lte->file_on_disk_fp = fopen(lte->file_on_disk, "rb"); + if (!lte->file_on_disk_fp) { + ERROR_WITH_ERRNO("Failed to open the file `%s' for " + "reading", lte->file_on_disk); + ret = WIMLIB_ERR_OPEN; + goto out; + } + } +#ifdef WITH_NTFS_3G + else if (lte->resource_location == RESOURCE_IN_NTFS_VOLUME + && !lte->attr) + { + struct ntfs_location *loc = lte->ntfs_loc; + wimlib_assert(loc); + ni = ntfs_pathname_to_inode(*loc->ntfs_vol_p, NULL, loc->path_utf8); + if (!ni) { + ERROR_WITH_ERRNO("Failed to open inode `%s' in NTFS " + "volume", loc->path_utf8); + ret = WIMLIB_ERR_NTFS_3G; + goto out; + } + lte->attr = ntfs_attr_open(ni, + loc->is_reparse_point ? AT_REPARSE_POINT : AT_DATA, + (ntfschar*)loc->stream_name_utf16, + loc->stream_name_utf16_num_chars); + if (!lte->attr) { + ERROR_WITH_ERRNO("Failed to open attribute of `%s' in " + "NTFS volume", loc->path_utf8); + ret = WIMLIB_ERR_NTFS_3G; + goto out_fclose; + } + } +#endif + + /* If we aren't doing a raw copy, we will compute the SHA1 message + * digest of the resource as we read it, and verify it's the same as the + * hash given in the lookup table entry once we've finished reading the + * resource. */ + SHA_CTX ctx; + if (!raw) + sha1_init(&ctx); + + /* While there are still bytes remaining in the WIM resource, read a + * chunk of the resource, update SHA1, then write that chunk using the + * desired compression type. */ + do { + u64 to_read = min(bytes_remaining, WIM_CHUNK_SIZE); + ret = read_wim_resource(lte, buf, to_read, offset, raw); + if (ret != 0) + goto out_fclose; + if (!raw) + sha1_update(&ctx, buf, to_read); + ret = write_wim_resource_chunk(buf, to_read, out_fp, + out_ctype, chunk_tab); + if (ret != 0) + goto out_fclose; + bytes_remaining -= to_read; + offset += to_read; + } while (bytes_remaining); + + /* If writing a compressed resource and not doing a raw copy, write the + * chunk table, and finish_wim_resource_chunk_tab() will provide the + * compressed size of the resource we wrote. Otherwise, the compressed + * size of the written resource is the same as the compressed size of + * the existing resource. */ + if (out_ctype != WIM_COMPRESSION_TYPE_NONE && !raw) { + ret = finish_wim_resource_chunk_tab(chunk_tab, out_fp, + &new_compressed_size); + if (ret != 0) + goto out_fclose; + } else { + new_compressed_size = old_compressed_size; + } + + /* Verify SHA1 message digest of the resource, unless we are doing a raw + * write (in which case we never even saw the uncompressed data). Or, + * if the hash we had before is all 0's, just re-set it to be the new + * hash. */ + if (!raw) { + u8 md[SHA1_HASH_SIZE]; + sha1_final(md, &ctx); + if (is_zero_hash(lte->hash)) { + copy_hash(lte->hash, md); + } else if (!hashes_equal(md, lte->hash)) { + ERROR("WIM resource has incorrect hash!"); + if (lte->resource_location == RESOURCE_IN_FILE_ON_DISK) { + ERROR("We were reading it from `%s'; maybe it changed " + "while we were reading it.", + lte->file_on_disk); + } + ret = WIMLIB_ERR_INVALID_RESOURCE_HASH; + goto out_fclose; + } + } + + if (new_compressed_size >= original_size && + out_ctype != WIM_COMPRESSION_TYPE_NONE && !raw) + { + /* Oops! We compressed the resource to larger than the original + * size. Write the resource uncompressed instead. */ + if (fseeko(out_fp, file_offset, SEEK_SET) != 0) { + ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" " + "of output WIM file", file_offset); + ret = WIMLIB_ERR_WRITE; + goto out_fclose; + } + ret = write_wim_resource(lte, out_fp, WIM_COMPRESSION_TYPE_NONE, + out_res_entry); + if (ret != 0) + goto out_fclose; + if (fflush(out_fp) != 0) { + ERROR_WITH_ERRNO("Failed to flush output WIM file"); + ret = WIMLIB_ERR_WRITE; + goto out_fclose; + } + if (ftruncate(fileno(out_fp), file_offset + out_res_entry->size) != 0) { + ERROR_WITH_ERRNO("Failed to truncate output WIM file"); + ret = WIMLIB_ERR_WRITE; + } + goto out_fclose; + } + wimlib_assert(new_compressed_size <= original_size); + if (out_res_entry) { + out_res_entry->size = new_compressed_size; + out_res_entry->original_size = original_size; + out_res_entry->offset = file_offset; + out_res_entry->flags = lte->resource_entry.flags + & ~WIM_RESHDR_FLAG_COMPRESSED; + if (out_ctype != WIM_COMPRESSION_TYPE_NONE) + out_res_entry->flags |= WIM_RESHDR_FLAG_COMPRESSED; + } +out_fclose: + if (lte->resource_location == RESOURCE_IN_FILE_ON_DISK + && lte->file_on_disk_fp) { + fclose(lte->file_on_disk_fp); + lte->file_on_disk_fp = NULL; + } +#ifdef WITH_NTFS_3G + else if (lte->resource_location == RESOURCE_IN_NTFS_VOLUME) { + if (lte->attr) { + ntfs_attr_close(lte->attr); + lte->attr = NULL; + } if (ni) { + ntfs_inode_close(ni); + } + } +#endif +out: + FREE(chunk_tab); + return ret; +} + +/* Like write_wim_resource(), but the resource is specified by a buffer of + * uncompressed data rather a lookup table entry; also writes the SHA1 hash of + * the buffer to @hash. */ +static int write_wim_resource_from_buffer(const u8 *buf, u64 buf_size, + FILE *out_fp, int out_ctype, + struct resource_entry *out_res_entry, + u8 hash[SHA1_HASH_SIZE]) +{ + /* Set up a temporary lookup table entry that we provide to + * write_wim_resource(). */ + struct lookup_table_entry lte; + int ret; + lte.resource_entry.flags = 0; + lte.resource_entry.original_size = buf_size; + lte.resource_entry.size = buf_size; + lte.resource_entry.offset = 0; + lte.resource_location = RESOURCE_IN_ATTACHED_BUFFER; + lte.attached_buffer = (u8*)buf; + + zero_out_hash(lte.hash); + ret = write_wim_resource(<e, out_fp, out_ctype, out_res_entry); + if (ret != 0) + return ret; + copy_hash(hash, lte.hash); + return 0; +} + +/* + * Extracts the first @size bytes of the WIM resource specified by @lte to the + * open file descriptor @fd. + * + * Returns 0 on success; nonzero on failure. + */ +int extract_wim_resource_to_fd(const struct lookup_table_entry *lte, int fd, + u64 size) +{ + u64 bytes_remaining = size; + u8 buf[min(WIM_CHUNK_SIZE, bytes_remaining)]; + u64 offset = 0; + int ret = 0; + u8 hash[SHA1_HASH_SIZE]; + + SHA_CTX ctx; + sha1_init(&ctx); + + while (bytes_remaining) { + u64 to_read = min(bytes_remaining, WIM_CHUNK_SIZE); + ret = read_wim_resource(lte, buf, to_read, offset, false); + if (ret != 0) + break; + sha1_update(&ctx, buf, to_read); + if (full_write(fd, buf, to_read) < 0) { + ERROR_WITH_ERRNO("Error extracting WIM resource"); + return WIMLIB_ERR_WRITE; + } + bytes_remaining -= to_read; + offset += to_read; + } + sha1_final(hash, &ctx); + if (!hashes_equal(hash, lte->hash)) { + ERROR("Invalid checksum on a WIM resource " + "(detected when extracting to external file)"); + ERROR("The following WIM resource is invalid:"); + print_lookup_table_entry(lte); + return WIMLIB_ERR_INVALID_RESOURCE_HASH; + } + return 0; +} + +/* + * Extracts the WIM resource specified by @lte to the open file descriptor @fd. + * + * Returns 0 on success; nonzero on failure. + */ +int extract_full_wim_resource_to_fd(const struct lookup_table_entry *lte, int fd) +{ + return extract_wim_resource_to_fd(lte, fd, wim_resource_size(lte)); +} + +/* + * Copies the file resource specified by the lookup table entry @lte from the + * input WIM to the output WIM that has its FILE * given by + * ((WIMStruct*)wim)->out_fp. + * + * The output_resource_entry, out_refcnt, and part_number fields of @lte are + * updated. + * + * Metadata resources are not copied (they are handled elsewhere for joining and + * splitting). + */ +int copy_resource(struct lookup_table_entry *lte, void *wim) +{ + WIMStruct *w = wim; + int ret; + + if ((lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA) && + !w->write_metadata) + return 0; + + ret = write_wim_resource(lte, w->out_fp, + wim_resource_compression_type(lte), + <e->output_resource_entry); + if (ret != 0) + return ret; + lte->out_refcnt = lte->refcnt; + lte->part_number = w->hdr.part_number; + return 0; +} + +/* + * Writes a dentry's resources, including the main file resource as well as all + * alternate data streams, to the output file. + * + * @dentry: The dentry for the file. + * @wim_p: A pointer to the WIMStruct containing @dentry. + * + * @return zero on success, nonzero on failure. + */ +int write_dentry_resources(struct dentry *dentry, void *wim_p) +{ + WIMStruct *w = wim_p; + int ret = 0; + struct lookup_table_entry *lte; + int ctype = wimlib_get_compression_type(w); + + if (w->write_flags & WIMLIB_WRITE_FLAG_VERBOSE) { + wimlib_assert(dentry->full_path_utf8); + printf("Writing streams for `%s'\n", dentry->full_path_utf8); + } + + for (unsigned i = 0; i <= dentry->num_ads; i++) { + lte = dentry_stream_lte(dentry, i, w->lookup_table); + if (lte && ++lte->out_refcnt == 1) { + ret = write_wim_resource(lte, w->out_fp, ctype, + <e->output_resource_entry); + if (ret != 0) + break; + } + } + return ret; } /* @@ -515,103 +1100,243 @@ int resource_compression_type(int wim_ctype, int reshdr_flags) * length 8, because that's how long the 'length' field is. * * @fp: The FILE* for the input WIM file. - * @res_entry: The resource entry for the metadata resource (a.k.a the metadata - * for the metadata) * @wim_ctype: The compression type of the WIM file. - * @root_dentry_p: A pointer to a pointer to a struct dentry structure into which the - * root dentry is allocated and returned. + * @imd: Pointer to the image metadata structure. Its `metadata_lte' + * member specifies the lookup table entry for the metadata + * resource. The rest of the image metadata entry will be filled + * in by this function. * - * @return: True on success, false on failure. + * @return: Zero on success, nonzero on failure. */ -int read_metadata_resource(FILE *fp, const struct resource_entry *res_entry, - int wim_ctype, struct dentry **root_dentry_p) +int read_metadata_resource(WIMStruct *w, struct image_metadata *imd) { u8 *buf; - int ctype; u32 dentry_offset; int ret; struct dentry *dentry; - - DEBUG("Reading metadata resource: length = %lu, offset = %lu\n", - res_entry->original_size, res_entry->offset); - - if (res_entry->original_size < 8) { - ERROR("Expected at least 8 bytes for the metadata " - "resource!\n"); + struct link_group_table *lgt; + const struct lookup_table_entry *metadata_lte; + u64 metadata_len; + u64 metadata_offset; + + metadata_lte = imd->metadata_lte; + metadata_len = wim_resource_size(metadata_lte); + metadata_offset = metadata_lte->resource_entry.offset; + + DEBUG("Reading metadata resource: length = %"PRIu64", " + "offset = %"PRIu64"", metadata_len, metadata_offset); + + /* There is no way the metadata resource could possibly be less than (8 + * + WIM_DENTRY_DISK_SIZE) bytes, where the 8 is for security data (with + * no security descriptors) and WIM_DENTRY_DISK_SIZE is for the root + * dentry. */ + if (metadata_len < 8 + WIM_DENTRY_DISK_SIZE) { + ERROR("Expected at least %u bytes for the metadata resource", + 8 + WIM_DENTRY_DISK_SIZE); return WIMLIB_ERR_INVALID_RESOURCE_SIZE; } /* Allocate memory for the uncompressed metadata resource. */ - buf = MALLOC(res_entry->original_size); + buf = MALLOC(metadata_len); if (!buf) { ERROR("Failed to allocate %"PRIu64" bytes for uncompressed " - "metadata resource!\n", - res_entry->original_size); + "metadata resource", metadata_len); return WIMLIB_ERR_NOMEM; } - /* Determine the compression type of the metadata resource. */ - ctype = resource_compression_type(wim_ctype, res_entry->flags); - /* Read the metadata resource into memory. (It may be compressed.) */ - ret = read_full_resource(fp, res_entry->size, - res_entry->original_size, res_entry->offset, - ctype, buf); + ret = read_full_wim_resource(metadata_lte, buf); if (ret != 0) - goto err1; + goto out_free_buf; - DEBUG("Finished reading metadata resource into memory.\n"); + DEBUG("Finished reading metadata resource into memory."); -#if 0 - /* Read the security data into a WIMSecurityData structure. */ - if (!read_security_data(buf, res_entry->original_size, sd)) - goto err1; -#endif + /* The root directory entry starts after security data, aligned on an + * 8-byte boundary within the metadata resource. + * + * The security data starts with a 4-byte integer giving its total + * length, so if we round that up to an 8-byte boundary that gives us + * the offset of the root dentry. + * + * Here we read the security data into a wim_security_data structure, + * and if successful, go ahead and calculate the offset in the metadata + * resource of the root dentry. */ + + ret = read_security_data(buf, metadata_len, &imd->security_data); + if (ret != 0) + goto out_free_buf; + get_u32(buf, &dentry_offset); + if (dentry_offset == 0) + dentry_offset = 8; + dentry_offset = (dentry_offset + 7) & ~7; + + /* Allocate memory for the root dentry and read it into memory */ dentry = MALLOC(sizeof(struct dentry)); if (!dentry) { - ERROR("Failed to allocate %zu bytes for root dentry!\n", - sizeof(struct dentry)); + ERROR("Failed to allocate %zu bytes for root dentry", + sizeof(struct dentry)); ret = WIMLIB_ERR_NOMEM; - goto err1; + goto out_free_security_data; } - - /* Read the root directory entry starts after security data, on an - * 8-byte aligned address. - * - * The security data starts with a 4-byte integer giving its total - * length. */ - get_u32(buf, &dentry_offset); - dentry_offset += (8 - dentry_offset % 8) % 8; - ret = read_dentry(buf, res_entry->original_size, dentry_offset, dentry); - if (ret != 0) - goto err1; + ret = read_dentry(buf, metadata_len, dentry_offset, dentry); /* This is the root dentry, so set its pointers correctly. */ dentry->parent = dentry; dentry->next = dentry; dentry->prev = dentry; + if (ret != 0) + goto out_free_dentry_tree; - /* Now read the entire directory entry tree. */ - ret = read_dentry_tree(buf, res_entry->original_size, dentry); + /* Now read the entire directory entry tree into memory. */ + DEBUG("Reading dentry tree"); + ret = read_dentry_tree(buf, metadata_len, dentry); if (ret != 0) - goto err2; + goto out_free_dentry_tree; /* Calculate the full paths in the dentry tree. */ + DEBUG("Calculating dentry full paths"); ret = for_dentry_in_tree(dentry, calculate_dentry_full_path, NULL); if (ret != 0) - goto err2; + goto out_free_dentry_tree; + + /* Build hash table that maps hard link group IDs to dentry sets */ + DEBUG("Building link group table"); + lgt = new_link_group_table(9001); + if (!lgt) + goto out_free_dentry_tree; + ret = for_dentry_in_tree(dentry, link_group_table_insert, lgt); + if (ret != 0) + goto out_free_lgt; - *root_dentry_p = dentry; - FREE(buf); - return ret; -err2: - free_dentry_tree(dentry, NULL, false); -err1: + DEBUG("Fixing inconsistencies in the link groups"); + ret = fix_link_groups(lgt); + if (ret != 0) + goto out_free_lgt; + + DEBUG("Running miscellaneous verifications on the dentry tree"); + ret = for_dentry_in_tree(dentry, verify_dentry, w); + if (ret != 0) + goto out_free_lgt; + + DEBUG("Done reading image metadata"); + + imd->lgt = lgt; + imd->root_dentry = dentry; + goto out_free_buf; +out_free_lgt: + free_link_group_table(lgt); +out_free_dentry_tree: + free_dentry_tree(dentry, NULL); +out_free_security_data: + free_security_data(imd->security_data); + imd->security_data = NULL; +out_free_buf: FREE(buf); return ret; } +/* Write the metadata resource for the current WIM image. */ +int write_metadata_resource(WIMStruct *w) +{ + u8 *buf; + u8 *p; + int ret; + u64 subdir_offset; + struct dentry *root; + struct lookup_table_entry *lte; + u64 metadata_original_size; + const struct wim_security_data *sd; + const unsigned random_tail_len = 20; + + DEBUG("Writing metadata resource for image %d", w->current_image); + + root = wim_root_dentry(w); + sd = wim_security_data(w); + + /* We do not allow the security data pointer to be NULL, although it may + * point to an empty security data with no entries. */ + wimlib_assert(sd); + + /* Offset of first child of the root dentry. It's equal to: + * - The total length of the security data, rounded to the next 8-byte + * boundary, + * - plus the total length of the root dentry, + * - plus 8 bytes for an end-of-directory entry following the root + * dentry (shouldn't really be needed, but just in case...) + */ + subdir_offset = ((sd->total_length + 7) & ~7) + + dentry_correct_total_length(root) + 8; + + /* Calculate the subdirectory offsets for the entire dentry tree. */ + calculate_subdir_offsets(root, &subdir_offset); + + /* Total length of the metadata resource (uncompressed) */ + metadata_original_size = subdir_offset + random_tail_len; + + /* Allocate a buffer to contain the uncompressed metadata resource */ + buf = MALLOC(metadata_original_size); + if (!buf) { + ERROR("Failed to allocate %"PRIu64" bytes for " + "metadata resource", metadata_original_size); + return WIMLIB_ERR_NOMEM; + } + /* Write the security data into the resource buffer */ + p = write_security_data(sd, buf); + + /* Write the dentry tree into the resource buffer */ + DEBUG("Writing dentry tree."); + p = write_dentry_tree(root, p); + + /* + * Append 20 random bytes to the metadata resource so that we don't have + * identical metadata resources if we happen to append exactly the same + * image twice without any changes in timestamps. If this were to + * happen, it would cause confusion about the number and order of images + * in the WIM. + */ + randomize_byte_array(p, random_tail_len); + + /* We MUST have exactly filled the buffer; otherwise we calculated its + * size incorrectly or wrote the data incorrectly. */ + wimlib_assert(p - buf + random_tail_len == metadata_original_size); + + /* Get the lookup table entry for the metadata resource so we can update + * it. */ + lte = wim_metadata_lookup_table_entry(w); + + /* Write the metadata resource to the output WIM using the proper + * compression type. The lookup table entry for the metadata resource + * is updated. */ + ret = write_wim_resource_from_buffer(buf, metadata_original_size, + w->out_fp, + wimlib_get_compression_type(w), + <e->output_resource_entry, + lte->hash); + if (ret != 0) + goto out; + + /* It's very likely the SHA1 message digest of the metadata resource, so + * re-insert the lookup table entry into the lookup table. */ + lookup_table_unlink(w->lookup_table, lte); + lookup_table_insert(w->lookup_table, lte); + + /* We do not allow a metadata resource to be referenced multiple times, + * and the 20 random bytes appended to it should make it extremely + * likely for each metadata resource to be unique, even if the exact + * same image is captured. */ + wimlib_assert(lte->out_refcnt == 0); + lte->out_refcnt = 1; + + /* Make sure that the resource entry is written marked with the metadata + * flag. */ + lte->output_resource_entry.flags |= WIM_RESHDR_FLAG_METADATA; +out: + /* All the data has been written to the new WIM; no need for the buffer + * anymore */ + FREE(buf); + return ret; +}