/*
* integrity.c
*
- * WIM files can optionally contain an array of SHA1 message digests at the end,
- * one digest for each 1 MB of the file. This file implements the checking of
- * the digests, and the writing of the digests for new WIM files.
+ * WIM files can optionally contain a table of SHA1 message digests at the end,
+ * one digest for each chunk of the file of some specified size (often 10 MB).
+ * This file implements the checking and writing of this table.
*/
/*
- * Copyright (C) 2012 Eric Biggers
+ * Copyright (C) 2012, 2013 Eric Biggers
*
* This file is part of wimlib, a library for working with WIM files.
*
*/
#include "wimlib_internal.h"
-#include "io.h"
+#include "buffer_io.h"
#include "sha1.h"
/* Size, in bytes, of each SHA1-summed chunk, when wimlib writes integrity
u8 sha1sums[0][20];
};
-static int calculate_chunk_sha1(FILE *fp, size_t this_chunk_size,
- off_t offset, u8 sha1_md[])
+static int
+calculate_chunk_sha1(int in_fd, size_t this_chunk_size,
+ off_t offset, u8 sha1_md[])
{
- int ret;
u8 buf[BUFFER_SIZE];
SHA_CTX ctx;
size_t bytes_remaining;
size_t bytes_to_read;
size_t bytes_read;
- ret = fseeko(fp, offset, SEEK_SET);
- if (ret != 0) {
- ERROR_WITH_ERRNO("Can't seek to offset "
- "%"PRIu64" in WIM", offset);
- return WIMLIB_ERR_READ;
- }
bytes_remaining = this_chunk_size;
sha1_init(&ctx);
do {
bytes_to_read = min(bytes_remaining, sizeof(buf));
- bytes_read = fread(buf, 1, bytes_to_read, fp);
+ bytes_read = full_pread(in_fd, buf, bytes_to_read, offset);
if (bytes_read != bytes_to_read) {
- if (feof(fp)) {
- ERROR("Unexpected EOF while calculating "
- "integrity checksums");
- } else {
- ERROR_WITH_ERRNO("File stream error while "
- "calculating integrity "
- "checksums");
- }
+ ERROR_WITH_ERRNO("Read error while calculating "
+ "integrity checksums");
return WIMLIB_ERR_READ;
}
sha1_update(&ctx, buf, bytes_read);
bytes_remaining -= bytes_read;
+ offset += bytes_read;
} while (bytes_remaining);
sha1_final(sha1_md, &ctx);
return 0;
/*
- * Reads the integrity table from a WIM file.
+ * read_integrity_table: - Reads the integrity table from a WIM file.
*
* @res_entry:
* The resource entry that specifies the location of the integrity table.
* The integrity table must exist (i.e. res_entry->offset must not be 0).
*
- * @fp:
- * FILE * to the WIM file, opened for reading.
+ * @in_fd:
+ * File descriptor to the WIM file, opened for reading.
*
* @num_checked_bytes:
* Number of bytes of data that should be checked by the integrity table.
* data.
* * WIMLIB_ERR_READ: Could not read the integrity data from the WIM file.
*/
-static int read_integrity_table(const struct resource_entry *res_entry,
- FILE *fp,
- u64 num_checked_bytes,
- struct integrity_table **table_ret)
+static int
+read_integrity_table(const struct resource_entry *res_entry,
+ int in_fd,
+ u64 num_checked_bytes,
+ struct integrity_table **table_ret)
{
- struct integrity_table *table = NULL;
- int ret = 0;
+ struct integrity_table *table;
+ int ret;
u64 expected_size;
u64 expected_num_entries;
- if (res_entry->original_size < 12) {
- ERROR("Integrity table is too short (expected at least 12 bytes)");
- ret = WIMLIB_ERR_INVALID_INTEGRITY_TABLE;
- goto out;
+ if (resource_is_compressed(res_entry)) {
+ ERROR("Didn't expect a compressed integrity table");
+ return WIMLIB_ERR_INVALID_INTEGRITY_TABLE;
}
- if (res_entry->flags & WIM_RESHDR_FLAG_COMPRESSED) {
- ERROR("Didn't expect a compressed integrity table");
- ret = WIMLIB_ERR_INVALID_INTEGRITY_TABLE;
- goto out;
+ if (res_entry->size < 8 || res_entry->size > 0xffffffff) {
+ ERROR("Integrity table resource header is invalid");
+ return WIMLIB_ERR_INVALID_INTEGRITY_TABLE;
}
/* Read the integrity table into memory. */
- if ((sizeof(size_t) < sizeof(u64)
- && res_entry->size > ~(size_t)0)
- || ((table = MALLOC(res_entry->size)) == NULL))
- {
- ERROR("Out of memory (needed %zu bytes for integrity table)",
+ table = MALLOC((size_t)res_entry->size);
+ if (table == NULL) {
+ ERROR("Can't allocate %zu bytes for integrity table",
(size_t)res_entry->size);
- ret = WIMLIB_ERR_NOMEM;
- goto out;
+ return WIMLIB_ERR_NOMEM;
}
- ret = read_uncompressed_resource(fp, res_entry->offset,
- res_entry->size, (void*)table);
-
- if (ret != 0) {
- ERROR("Failed to read integrity table (size = %"PRIu64", "
+ if (full_pread(in_fd, table, res_entry->size,
+ res_entry->offset) != res_entry->size)
+ {
+ ERROR("Failed to read integrity table (size = %zu, "
" offset = %"PRIu64")",
- (u64)res_entry->size, res_entry->offset);
- goto out;
+ (size_t)res_entry->size, res_entry->offset);
+ ret = WIMLIB_ERR_READ;
+ goto out_free_table;
}
table->size = le32_to_cpu(table->size);
if (table->size != res_entry->size) {
ERROR("Inconsistent integrity table sizes: Table header says "
- "%u bytes but resource entry says %"PRIu64" bytes",
- table->size, (u64)res_entry->size);
+ "%u bytes but resource entry says %u bytes",
+ table->size, (unsigned)res_entry->size);
ret = WIMLIB_ERR_INVALID_INTEGRITY_TABLE;
- goto out;
+ goto out_free_table;
}
DEBUG("table->size = %u, table->num_entries = %u, "
"bytes to hold %u entries",
table->size, expected_size, table->num_entries);
ret = WIMLIB_ERR_INVALID_INTEGRITY_TABLE;
- goto out;
+ goto out_free_table;
}
if (table->chunk_size == 0) {
ERROR("Cannot use integrity chunk size of 0");
ret = WIMLIB_ERR_INVALID_INTEGRITY_TABLE;
- goto out;
+ goto out_free_table;
}
expected_num_entries = DIV_ROUND_UP(num_checked_bytes, table->chunk_size);
if (table->num_entries != expected_num_entries) {
- ERROR("%"PRIu64" entries would be required to checksum "
- "the %"PRIu64" bytes from the end of the header to the",
+ ERROR("%"PRIu64" integrity table entries would be required "
+ "to checksum the %"PRIu64" bytes from the end of the "
+ "header to the",
expected_num_entries, num_checked_bytes);
ERROR("end of the lookup table with a chunk size of %u, but "
"there were only %u entries",
table->chunk_size, table->num_entries);
ret = WIMLIB_ERR_INVALID_INTEGRITY_TABLE;
+ goto out_free_table;
}
+ *table_ret = table;
+ ret = 0;
+ goto out;
+out_free_table:
+ FREE(table);
out:
- if (ret == 0)
- *table_ret = table;
- else
- FREE(table);
return ret;
}
/*
+ * calculate_integrity_table():
+ *
* Calculates an integrity table for the data in a file beginning at offset 208
* (WIM_HEADER_DISK_SIZE).
*
- * @fp:
- * FILE * for the file to be checked, opened for reading. Does not need to
- * be at any specific location in the file.
+ * @in_fd:
+ * File descriptor for the file to be checked, opened for reading. Does
+ * not need to be at any specific location in the file.
*
* @new_check_end:
* Offset of byte after the last byte to be checked.
*
* @old_table:
- * If non-NULL, a pointer to the table containing previously contained
+ * If non-NULL, a pointer to the table containing the previously calculated
* integrity data for a prefix of this file.
*
* @old_check_end:
*
* Returns 0 on success; nonzero on failure.
*/
-static int calculate_integrity_table(FILE *fp,
- off_t new_check_end,
- const struct integrity_table *old_table,
- off_t old_check_end,
- wimlib_progress_func_t progress_func,
- struct integrity_table **integrity_table_ret)
+static int
+calculate_integrity_table(int in_fd,
+ off_t new_check_end,
+ const struct integrity_table *old_table,
+ off_t old_check_end,
+ wimlib_progress_func_t progress_func,
+ struct integrity_table **integrity_table_ret)
{
- int ret = 0;
+ int ret;
size_t chunk_size = INTEGRITY_CHUNK_SIZE;
/* If an old table is provided, set the chunk size to be compatible with
* the old chunk size, unless the old chunk size was weird. */
if (old_table != NULL) {
- if (old_table->chunk_size < INTEGRITY_MIN_CHUNK_SIZE ||
+ if (old_table->num_entries == 0 ||
+ old_table->chunk_size < INTEGRITY_MIN_CHUNK_SIZE ||
old_table->chunk_size > INTEGRITY_MAX_CHUNK_SIZE)
old_table = NULL;
else
copy_hash(new_table->sha1sums[i], old_table->sha1sums[i]);
} else {
/* Calculate the SHA1 message digest of this chunk */
- ret = calculate_chunk_sha1(fp, this_chunk_size,
+ ret = calculate_chunk_sha1(in_fd, this_chunk_size,
offset, new_table->sha1sums[i]);
- if (ret != 0)
- break;
+ if (ret) {
+ FREE(new_table);
+ return ret;
+ }
}
offset += this_chunk_size;
if (progress_func) {
&progress);
}
}
- if (ret == 0)
- *integrity_table_ret = new_table;
- else
- FREE(new_table);
- return ret;
+ *integrity_table_ret = new_table;
+ return 0;
}
/*
+ * write_integrity_table():
+ *
* Writes a WIM integrity table (a list of SHA1 message digests of raw 10 MiB
* chunks of the file).
*
* cannot be read, a warning is printed and the integrity information is
* re-calculated.
*
- * @fp:
- * FILE * to the WIM file, opened read-write, positioned at the location at
- * which the integrity table is to be written.
+ * @fd:
+ * File descriptor to the WIM file, opened read-write, positioned at the
+ * location at which the integrity table is to be written.
*
* @integrity_res_entry:
* Resource entry which will be set to point to the integrity table on
* * WIMLIB_ERR_READ: Could not read a chunk of data that needed
* to be checked.
*/
-int write_integrity_table(FILE *fp,
- struct resource_entry *integrity_res_entry,
- off_t new_lookup_table_end,
- off_t old_lookup_table_end,
- wimlib_progress_func_t progress_func)
+int
+write_integrity_table(int fd,
+ struct resource_entry *integrity_res_entry,
+ off_t new_lookup_table_end,
+ off_t old_lookup_table_end,
+ wimlib_progress_func_t progress_func)
{
struct integrity_table *old_table;
struct integrity_table *new_table;
wimlib_assert(old_lookup_table_end <= new_lookup_table_end);
- cur_offset = ftello(fp);
- if (cur_offset == -1) {
- ERROR_WITH_ERRNO("Failed to get offset in WIM");
+ cur_offset = filedes_offset(fd);
+ if (cur_offset == -1)
return WIMLIB_ERR_WRITE;
- }
if (integrity_res_entry->offset == 0 || old_lookup_table_end == 0) {
old_table = NULL;
} else {
- ret = read_integrity_table(integrity_res_entry, fp,
+ ret = read_integrity_table(integrity_res_entry, fd,
old_lookup_table_end - WIM_HEADER_DISK_SIZE,
&old_table);
if (ret == WIMLIB_ERR_INVALID_INTEGRITY_TABLE) {
}
}
- ret = calculate_integrity_table(fp, new_lookup_table_end,
+ ret = calculate_integrity_table(fd, new_lookup_table_end,
old_table, old_lookup_table_end,
progress_func, &new_table);
- if (ret != 0)
+ if (ret)
goto out_free_old_table;
new_table_size = new_table->size;
new_table->num_entries = cpu_to_le32(new_table->num_entries);
new_table->chunk_size = cpu_to_le32(new_table->chunk_size);
- if (fseeko(fp, cur_offset, SEEK_SET) != 0) {
- ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" of WIM to "
- "write integrity table", cur_offset);
- ret = WIMLIB_ERR_WRITE;
- goto out_free_new_table;
- }
-
- if (fwrite(new_table, 1, new_table_size, fp) != new_table_size) {
+ if (full_write(fd, new_table, new_table_size) != new_table_size) {
ERROR_WITH_ERRNO("Failed to write WIM integrity table");
ret = WIMLIB_ERR_WRITE;
} else {
integrity_res_entry->flags = 0;
ret = 0;
}
-out_free_new_table:
FREE(new_table);
out_free_old_table:
FREE(old_table);
}
/*
+ * verify_integrity():
+ *
* Checks a WIM for consistency with the integrity table.
*
- * @fp:
- * FILE * to the WIM file, opened for reading.
+ * @in_fd:
+ * File descriptor to the WIM file, opened for reading.
*
* @table:
* The integrity table for the WIM, read into memory.
* were no inconsistencies.
* -1 (WIM_INTEGRITY_NOT_OK) if the WIM failed the integrity check.
*/
-static int verify_integrity(FILE *fp, const char *filename,
- const struct integrity_table *table,
- u64 bytes_to_check,
- wimlib_progress_func_t progress_func)
+static int
+verify_integrity(int in_fd, const tchar *filename,
+ const struct integrity_table *table,
+ u64 bytes_to_check,
+ wimlib_progress_func_t progress_func)
{
int ret;
u64 offset = WIM_HEADER_DISK_SIZE;
else
this_chunk_size = table->chunk_size;
- ret = calculate_chunk_sha1(fp, this_chunk_size, offset, sha1_md);
- if (ret != 0)
+ ret = calculate_chunk_sha1(in_fd, this_chunk_size, offset, sha1_md);
+ if (ret)
return ret;
if (!hashes_equal(sha1_md, table->sha1sums[i]))
/*
+ * check_wim_integrity():
+ *
* Verifies the integrity of the WIM by making sure the SHA1 message digests of
* ~10 MiB chunks of the WIM match up with the values given in the integrity
- * tabel.
+ * table.
*
* @w:
* The WIM, opened for reading, and with the header already read.
* -2 (WIM_INTEGRITY_NONEXISTENT) if the WIM contains no integrity
* information.
*/
-int check_wim_integrity(WIMStruct *w, wimlib_progress_func_t progress_func)
+int
+check_wim_integrity(WIMStruct *w, wimlib_progress_func_t progress_func)
{
int ret;
u64 bytes_to_check;
bytes_to_check = end_lookup_table_offset - WIM_HEADER_DISK_SIZE;
- ret = read_integrity_table(&w->hdr.integrity, w->fp,
+ ret = read_integrity_table(&w->hdr.integrity, w->in_fd,
bytes_to_check, &table);
- if (ret != 0)
+ if (ret)
return ret;
- ret = verify_integrity(w->fp, w->filename, table,
+ ret = verify_integrity(w->in_fd, w->filename, table,
bytes_to_check, progress_func);
FREE(table);
return ret;
git://wimlib.net / wimlib / blobdiff