*/
#include "wimlib_internal.h"
-#include "io.h"
+#include "buffer_io.h"
#include "security.h"
/*
* invalid. However, a security descriptor like this exists in the Windows 7
* install.wim. Here, security descriptors matching this pattern are modified
* to have no SACL. This should make no difference since the SACL had no
- * entries anyway; however his ensures that that the security descriptors pass
+ * entries anyway; however this ensures that that the security descriptors pass
* the validation in libntfs-3g.
*/
-static void empty_sacl_fixup(char *descr, u64 *size_p)
+static void empty_sacl_fixup(u8 *descr, u64 *size_p)
{
if (*size_p >= sizeof(SecurityDescriptor)) {
SecurityDescriptor *sd = (SecurityDescriptor*)descr;
int ret;
u64 total_len;
+ /*
+ * Sorry this function is excessively complicated--- I'm just being
+ * extremely careful about integer overflows.
+ */
+
sd = MALLOC(sizeof(struct wim_security_data));
if (!sd) {
ERROR("Out of memory");
p = get_u32(p, &sd->total_length);
p = get_u32(p, (u32*)&sd->num_entries);
- if (sd->num_entries > 0x7fffffff) {
+ /* The security_id field of each dentry is a signed 32-bit integer, so
+ * the possible indices into the security descriptors table are 0
+ * through 0x7fffffff. Which means 0x80000000 security descriptors
+ * maximum. Not like you should ever have anywhere close to that many
+ * security descriptors! */
+ if (sd->num_entries > 0x80000000) {
ERROR("Security data has too many entries!");
- ret = WIMLIB_ERR_INVALID_SECURITY_DATA;
- goto out_free_sd;
+ goto out_invalid_sd;
}
/* Verify the listed total length of the security data is big enough to
ERROR("Security data total length (%u) is bigger than the "
"metadata resource length (%"PRIu64")",
sd->total_length, metadata_resource_len);
- ret = WIMLIB_ERR_INVALID_SECURITY_DATA;
- goto out_free_sd;
+ goto out_invalid_sd;
}
DEBUG("Reading security data: %u entries, length = %u",
sd->num_entries, sd->total_length);
if (sd->num_entries == 0) {
- /* No security data. */
- total_len = 8;
- goto out;
+ /* No security descriptors. */
+ if (sd->total_length != 0 && sd->total_length != 8) {
+ ERROR("Invalid security data length (%u): expected 0 or 8",
+ sd->total_length);
+ goto out_invalid_sd;
+ }
+ sd->total_length = 8;
+ goto out_return_sd;
}
u64 sizes_size = (u64)sd->num_entries * sizeof(u64);
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_SECURITY_DATA;
- goto out_free_sd;
+ goto out_invalid_sd;
+ }
+ if (sizeof(size_t) < 8 && sizes_size > 0xffffffff) {
+ ERROR("Too many security descriptors!");
+ goto out_invalid_sd;
}
sd->sizes = MALLOC(sizes_size);
if (!sd->sizes) {
"(current total length = %"PRIu64", security "
"descriptor size = %"PRIu64")",
total_len, sd->sizes[i]);
- ret = WIMLIB_ERR_INVALID_SECURITY_DATA;
- goto out_free_sd;
+ goto out_invalid_sd;
}
total_len += sd->sizes[i];
+ /* This check assures that the descriptor size fits in a 32 bit
+ * integer. Because if it didn't, the total length would come
+ * out bigger than sd->total_length, which is a 32 bit integer.
+ * */
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_SECURITY_DATA;
- goto out_free_sd;
+ goto out_invalid_sd;
}
sd->descriptors[i] = MALLOC(sd->sizes[i]);
if (!sd->descriptors[i]) {
p = get_bytes(p, sd->sizes[i], sd->descriptors[i]);
empty_sacl_fixup(sd->descriptors[i], &sd->sizes[i]);
}
-out:
- sd->total_length = (u32)total_len;
+ wimlib_assert(total_len <= 0xffffffff);
+ if (((total_len + 7) & ~7) != ((sd->total_length + 7) & ~7)) {
+ ERROR("Expected security data total length = %u, but "
+ "calculated %u", sd->total_length, (unsigned)total_len);
+ goto out_invalid_sd;
+ }
+ sd->total_length = total_len;
+out_return_sd:
*sd_p = sd;
return 0;
+out_invalid_sd:
+ ret = WIMLIB_ERR_INVALID_SECURITY_DATA;
out_free_sd:
free_security_data(sd);
return ret;
printf(" ACE Count = %u\n", ace_count);
p += sizeof(ACL);
- for (uint i = 0; i < acl->ace_count; i++) {
+ for (u16 i = 0; i < ace_count; i++) {
const ACEHeader *hdr = (const ACEHeader*)p;
printf(" [ACE]\n");
printf(" ACE type = %d\n", hdr->type);
print_byte_field(sid->identifier_authority,
sizeof(sid->identifier_authority));
putchar('\n');
- for (uint i = 0; i < sid->sub_authority_count; i++)
+ for (u8 i = 0; i < sid->sub_authority_count; i++)
printf(" Subauthority %u = %u\n",
i, le32_to_cpu(sid->sub_authority[i]));
putchar('\n');
void free_security_data(struct wim_security_data *sd)
{
- if (!sd)
- return;
- wimlib_assert(sd->refcnt != 0);
- if (--sd->refcnt == 0) {
- u8 **descriptors = sd->descriptors;
- u32 num_entries = sd->num_entries;
- if (descriptors)
- while (num_entries--)
- FREE(*descriptors++);
- FREE(sd->sizes);
- FREE(sd->descriptors);
- FREE(sd);
+ if (sd) {
+ wimlib_assert(sd->refcnt != 0);
+ if (--sd->refcnt == 0) {
+ u8 **descriptors = sd->descriptors;
+ u32 num_entries = sd->num_entries;
+ if (descriptors)
+ while (num_entries--)
+ FREE(*descriptors++);
+ FREE(sd->sizes);
+ FREE(sd->descriptors);
+ FREE(sd);
+ }
}
}
git://wimlib.net / wimlib / blobdiff