*
* Read the security data from the WIM. Doing anything with the security data
* is not yet implemented other than printing some information about it.
- *
+ */
+
+/*
* 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 "io.h"
#include "security.h"
-#ifdef ENABLE_SECURITY_DATA
-
/*
* Reads the security data from the metadata resource.
*
* @metadata_resource: An array that contains the uncompressed metadata
* resource for the WIM file.
- * @metadata_resource_len: The length of @metadata_resource.
- * @sd_p: A pointer to a pointer wim_security_data structure that will be filled
- * in with a pointer to a new wim_security_data structure on success.
+ * @metadata_resource_len: The length of @metadata_resource. It MUST be at
+ * least 8 bytes.
+ * @sd_p: A pointer to a pointer to a wim_security_data structure that
+ * will be filled in with a pointer to a new wim_security_data
+ * structure on success.
*
* Note: There is no `offset' argument because the security data is located at
* the beginning of the metadata resource.
*/
-int read_security_data(const u8 metadata_resource[],
- u64 metadata_resource_len, struct wim_security_data **sd_p)
+int read_security_data(const u8 metadata_resource[], u64 metadata_resource_len,
+ struct wim_security_data **sd_p)
{
struct wim_security_data *sd;
const u8 *p;
- u64 sizes_size;
+ int ret;
+ u64 total_len;
- if (metadata_resource_len < 8) {
- ERROR("Not enough space in %"PRIu64"-byte file resource for "
- "security data!\n", metadata_resource_len);
- return WIMLIB_ERR_INVALID_RESOURCE_SIZE;
- }
sd = MALLOC(sizeof(struct wim_security_data));
- if (!sd)
+ if (!sd) {
+ ERROR("Out of memory");
return WIMLIB_ERR_NOMEM;
- p = get_u32(metadata_resource, &sd->total_length);
+ }
+ sd->sizes = NULL;
+ sd->descriptors = NULL;
+ sd->refcnt = 1;
+
+ p = metadata_resource;
+ p = get_u32(p, &sd->total_length);
p = get_u32(p, &sd->num_entries);
/* Verify the listed total length of the security data is big enough to
* include the sizes array, verify that the file data is big enough to
- * include it as well, then allocate the array of sizes. */
- sizes_size = sd->num_entries * sizeof(u64);
+ * include it as well, then allocate the array of sizes.
+ *
+ * Note: The total length of the security data must fit in a 32-bit
+ * integer, even though each security descriptor size is a 64-bit
+ * integer. This is stupid, and we need to be careful not to actually
+ * let the security descriptor sizes be over 0xffffffff. */
+ if ((u64)sd->total_length > metadata_resource_len) {
+ ERROR("Security data total length (%u) is bigger than the "
+ "metadata resource length (%"PRIu64")",
+ sd->total_length, metadata_resource_len);
+ ret = WIMLIB_ERR_INVALID_RESOURCE_SIZE;
+ goto out_free_sd;
+ }
- DEBUG("Reading security data with %u entries\n", sd->num_entries);
+ DEBUG("Reading security data: %u entries, length = %u",
+ sd->num_entries, sd->total_length);
if (sd->num_entries == 0) {
- FREE(sd);
- return 0;
+ /* No security data. */
+ total_len = 8;
+ goto out;
}
+ u64 sizes_size = (u64)sd->num_entries * sizeof(u64);
u64 size_no_descriptors = 8 + sizes_size;
- if (size_no_descriptors > sd->total_length) {
- ERROR("Security data total length of %"PRIu64" is too short because\n"
- "there must be at least %"PRIu64" bytes of security "
- "data!\n", sd->total_length,
- 8 + sizes_size);
- FREE(sd);
- return WIMLIB_ERR_INVALID_RESOURCE_SIZE;
- }
- if (size_no_descriptors > metadata_resource_len) {
- ERROR("File resource of %"PRIu64" bytes is not big enough\n"
- "to hold security data of at least %"PRIu64" "
- "bytes!\n", metadata_resource_len, size_no_descriptors);
- FREE(sd);
- return WIMLIB_ERR_INVALID_RESOURCE_SIZE;
+ if (size_no_descriptors > (u64)sd->total_length) {
+ ERROR("Security data total length of %u is too short because "
+ "there must be at least %"PRIu64" bytes of security data",
+ sd->total_length, 8 + sizes_size);
+ ret = WIMLIB_ERR_INVALID_RESOURCE_SIZE;
+ goto out_free_sd;
}
sd->sizes = MALLOC(sizes_size);
if (!sd->sizes) {
- FREE(sd);
- return WIMLIB_ERR_NOMEM;
+ ret = WIMLIB_ERR_NOMEM;
+ goto out_free_sd;
}
/* Copy the sizes array in from the file data. */
/* Allocate the array of pointers to descriptors, and read them in. */
sd->descriptors = CALLOC(sd->num_entries, sizeof(u8*));
if (!sd->descriptors) {
- FREE(sd);
- FREE(sd->sizes);
- return WIMLIB_ERR_NOMEM;
+ ERROR("Out of memory while allocating security "
+ "descriptors");
+ ret = WIMLIB_ERR_NOMEM;
+ goto out_free_sd;
}
- u64 total_len = size_no_descriptors;
+ total_len = size_no_descriptors;
- for (uint i = 0; i < sd->num_entries; i++) {
- total_len += sd->sizes[i];
- if (total_len > sd->total_length) {
- ERROR("Security data total length of %"PRIu64" is too "
- "short because there are at least %"PRIu64" "
- "bytes of security data!\n",
- sd->total_length, total_len);
- free_security_data(sd);
- return WIMLIB_ERR_INVALID_RESOURCE_SIZE;
+ for (u32 i = 0; i < sd->num_entries; i++) {
+ /* Watch out for huge security descriptor sizes that could
+ * overflow the total length and wrap it around. */
+ if (total_len + sd->sizes[i] < total_len) {
+ ERROR("Caught overflow in security descriptor lengths "
+ "(current total length = %"PRIu64", security "
+ "descriptor size = %"PRIu64")",
+ total_len, sd->sizes[i]);
+ ret = WIMLIB_ERR_INVALID_SECURITY_DATA;
+ goto out_free_sd;
}
- if (total_len > metadata_resource_len) {
- ERROR("File resource of %"PRIu64" bytes is not big enough "
- "to hold security data of at least %"PRIu64" "
- "bytes!\n", metadata_resource_len, total_len);
- free_security_data(sd);
- return WIMLIB_ERR_INVALID_RESOURCE_SIZE;
+ total_len += sd->sizes[i];
+ if (total_len > (u64)sd->total_length) {
+ ERROR("Security data total length of %u is too short "
+ "because there are at least %"PRIu64" bytes of "
+ "security data", sd->total_length, total_len);
+ ret = WIMLIB_ERR_INVALID_RESOURCE_SIZE;
+ goto out_free_sd;
}
sd->descriptors[i] = MALLOC(sd->sizes[i]);
if (!sd->descriptors[i]) {
- free_security_data(sd);
- return WIMLIB_ERR_NOMEM;
+ ERROR("Out of memory while allocating security "
+ "descriptors");
+ ret = WIMLIB_ERR_NOMEM;
+ goto out_free_sd;
}
p = get_bytes(p, sd->sizes[i], sd->descriptors[i]);
}
- sd->refcnt = 1;
+out:
+ sd->total_length = (u32)total_len;
*sd_p = sd;
return 0;
+out_free_sd:
+ free_security_data(sd);
+ return ret;
}
/*
*/
u8 *write_security_data(const struct wim_security_data *sd, u8 *p)
{
- if (sd) {
- DEBUG("Writing security data (total_length = %u, "
- "num_entries = %u)\n", sd->total_length,
- sd->num_entries);
- u8 *orig_p = p;
- p = put_u32(p, sd->total_length);
- p = put_u32(p, sd->num_entries);
+ DEBUG("Writing security data (total_length = %"PRIu32", num_entries "
+ "= %"PRIu32")", sd->total_length, sd->num_entries);
- for (uint i = 0; i < sd->num_entries; i++)
- p = put_u64(p, sd->sizes[i]);
+ u8 *orig_p = p;
+ p = put_u32(p, sd->total_length);
+ p = put_u32(p, sd->num_entries);
- for (uint i = 0; i < sd->num_entries; i++)
- p = put_bytes(p, sd->sizes[i], sd->descriptors[i]);
+ for (u32 i = 0; i < sd->num_entries; i++)
+ p = put_u64(p, sd->sizes[i]);
- wimlib_assert(p - orig_p <= sd->total_length);
+ for (u32 i = 0; i < sd->num_entries; i++)
+ p = put_bytes(p, sd->sizes[i], sd->descriptors[i]);
- DEBUG("Successfully wrote security data.\n");
- return orig_p + sd->total_length;
- } else {
- DEBUG("Writing security data (total_length = 8, "
- "num_entries = 0)\n");
- p = put_u32(p, 8);
- return put_u32(p, 0);
+ wimlib_assert(p - orig_p == sd->total_length);
- }
+ DEBUG("Successfully wrote security data.");
+ return p;
}
/* XXX We don't actually do anything with the ACL's yet besides being able to
void print_security_data(const struct wim_security_data *sd)
{
puts("[SECURITY DATA]");
- if (sd) {
- printf("Length = %u bytes\n", sd->total_length);
- printf("Number of Entries = %u\n", sd->num_entries);
+ printf("Length = %"PRIu32" bytes\n", sd->total_length);
+ printf("Number of Entries = %"PRIu32"\n", sd->num_entries);
- u64 num_entries = (u64)sd->num_entries;
- for (u64 i = 0; i < num_entries; i++) {
- printf("[SecurityDescriptor %"PRIu64", "
- "length = %"PRIu64"]\n",
- i, sd->sizes[i]);
- print_security_descriptor(sd->descriptors[i],
- sd->sizes[i]);
- putchar('\n');
- }
- } else {
- puts("Length = 8 bytes\n"
- "Number of Entries = 0");
+ for (u32 i = 0; i < sd->num_entries; i++) {
+ printf("[SecurityDescriptor %"PRIu32", length = %"PRIu64"]\n",
+ i, sd->sizes[i]);
+ print_security_descriptor(sd->descriptors[i], sd->sizes[i]);
+ putchar('\n');
}
putchar('\n');
}
{
if (!sd)
return;
- wimlib_assert(sd->refcnt >= 1);
- if (sd->refcnt == 1) {
+ wimlib_assert(sd->refcnt != 0);
+ if (--sd->refcnt == 0) {
u8 **descriptors = sd->descriptors;
- u32 num_entries = sd->num_entries;
-
+ u32 num_entries = sd->num_entries;
if (descriptors)
while (num_entries--)
FREE(*descriptors++);
FREE(sd->sizes);
FREE(sd->descriptors);
FREE(sd);
- } else {
- sd->refcnt--;
}
}
-
-#endif
git://wimlib.net / wimlib / blobdiff