include/wimlib/reparse.h \
include/wimlib/resource.h \
include/wimlib/security.h \
+ include/wimlib/security_descriptor.h \
include/wimlib/sha1.h \
include/wimlib/timestamp.h \
include/wimlib/types.h \
--- /dev/null
+#ifndef _WIMLIB_SECURITY_DESCRIPTOR_H
+#define _WIMLIB_SECURITY_DESCRIPTOR_H
+
+#include "wimlib/compiler.h"
+#include "wimlib/types.h"
+
+/* Note: the data types in this header are prefixed with wimlib_ to avoid
+ * conflicts with the same types being defined in the libntfs-3g headers. */
+
+/* Windows NT security descriptor, in self-relative format */
+typedef struct {
+ /* Security descriptor revision; should be 1 */
+ u8 revision;
+
+ /* Padding */
+ u8 sbz1;
+
+ /* Bitwise OR of flags defined below, such as SE_DACL_PRESENT */
+ le16 control;
+
+ /* Offset of owenr SID structure in the security descriptor */
+ le32 owner_offset;
+
+ /* Offset of group SID structure in the security descriptor */
+ le32 group_offset;
+
+ /* Offset of System Access Control List (SACL) in security descriptor,
+ * or 0 if no SACL is present */
+ le32 sacl_offset;
+
+ /* Offset of Discretionary Access Control List (DACL) in security
+ * descriptor, or 0 if no DACL is present */
+ le32 dacl_offset;
+} _packed_attribute wimlib_SECURITY_DESCRIPTOR_RELATIVE;
+
+#define wimlib_SE_OWNER_DEFAULTED 0x0001
+#define wimlib_SE_GROUP_DEFAULTED 0x0002
+#define wimlib_SE_DACL_PRESENT 0x0004
+#define wimlib_SE_DACL_DEFAULTED 0x0008
+#define wimlib_SE_SACL_PRESENT 0x0010
+#define wimlib_SE_SACL_DEFAULTED 0x0020
+#define wimlib_SE_DACL_AUTO_INHERIT_REQ 0x0100
+#define wimlib_SE_SACL_AUTO_INHERIT_REQ 0x0200
+#define wimlib_SE_DACL_AUTO_INHERITED 0x0400
+#define wimlib_SE_SACL_AUTO_INHERITED 0x0800
+#define wimlib_SE_DACL_PROTECTED 0x1000
+#define wimlib_SE_SACL_PROTECTED 0x2000
+#define wimlib_SE_RM_CONTROL_VALID 0x4000
+#define wimlib_SE_SELF_RELATIVE 0x8000
+
+/* Header of a Windows NT access control entry */
+typedef struct {
+ /* Type of ACE */
+ u8 type;
+
+ /* Bitwise OR of inherit ACE flags */
+ u8 flags;
+
+ /* Size of the access control entry, including this header */
+ le16 size;
+} _packed_attribute wimlib_ACE_HEADER;
+
+/* Windows NT access control entry to grant rights to a user or group */
+typedef struct {
+ wimlib_ACE_HEADER hdr;
+ le32 mask;
+ le32 sid_start;
+} _packed_attribute wimlib_ACCESS_ALLOWED_ACE;
+
+/* Windows NT access control entry to deny rights to a user or group */
+typedef struct {
+ wimlib_ACE_HEADER hdr;
+ le32 mask;
+ le32 sid_start;
+} _packed_attribute wimlib_ACCESS_DENIED_ACE;
+
+/* Windows NT access control entry to audit access to the object */
+typedef struct {
+ wimlib_ACE_HEADER hdr;
+ le32 mask;
+ le32 sid_start;
+} _packed_attribute wimlib_SYSTEM_AUDIT_ACE;
+
+
+/* Header of a Windows NT access control list */
+typedef struct {
+ /* ACL_REVISION or ACL_REVISION_DS */
+ u8 revision;
+
+ /* padding */
+ u8 sbz1;
+
+ /* Total size of the ACL, including all access control entries */
+ le16 acl_size;
+
+ /* Number of access control entry structures that follow the ACL
+ * structure */
+ le16 ace_count;
+
+ /* padding */
+ le16 sbz2;
+} _packed_attribute wimlib_ACL;
+
+/* Windows NT security identifier (user or group) */
+typedef struct {
+
+ u8 revision;
+ u8 sub_authority_count;
+
+ /* Identifies the authority that issued the SID */
+ u8 identifier_authority[6];
+
+ le32 sub_authority[];
+} _packed_attribute wimlib_SID;
+
+#endif
#include "wimlib/ntfs_3g.h"
#include "wimlib/paths.h"
#include "wimlib/resource.h"
+#include "wimlib/security_descriptor.h"
static ntfs_volume *
ntfs_3g_apply_ctx_get_volume(struct apply_ctx *ctx)
return ret;
}
+static size_t
+sid_size(const wimlib_SID *sid)
+{
+ return offsetof(wimlib_SID, sub_authority) +
+ sizeof(le32) * sid->sub_authority_count;
+}
+
+/*
+ * sd_fixup - Fix up a Windows NT security descriptor for libntfs-3g.
+ *
+ * libntfs-3g validates security descriptors before setting them, but old
+ * versions contain bugs causing it to reject unusual but valid security
+ * descriptors:
+ *
+ * - Versions before 2013.1.13 reject security descriptors ending with an empty
+ * SACL (System Access Control List). This bug can be worked around either by
+ * moving the empty SACL earlier in the security descriptor or by removing the
+ * SACL entirely. The latter work-around is valid because an empty SACL is
+ * equivalent to a "null", or non-existent, SACL.
+ * - Versions up to and including 2013.1.13 reject security descriptors ending
+ * with an empty DACL (Discretionary Access Control List). This is very
+ * similar to the SACL bug and should be fixed in the next release after
+ * 2013.1.13. However, removing the DACL is not a valid workaround because
+ * this changes the meaning of the security descriptor--- an empty DACL allows
+ * no access, whereas a "null" DACL allows all access.
+ *
+ * If the security descriptor was fixed, this function returns an allocated
+ * buffer containing the fixed security descriptor, and its size is updated.
+ * Otherwise (or if no memory is available) the original descriptor is returned.
+ */
+static u8 *
+sd_fixup(const u8 *_desc, size_t *size_p)
+{
+ u32 owner_offset, group_offset, dacl_offset, sacl_offset;
+ bool owner_valid, group_valid;
+ size_t size = *size_p;
+ const wimlib_SECURITY_DESCRIPTOR_RELATIVE *desc =
+ (const wimlib_SECURITY_DESCRIPTOR_RELATIVE*)_desc;
+ wimlib_SECURITY_DESCRIPTOR_RELATIVE *desc_new;
+ u32 sid_offset;
+ const wimlib_SID *owner, *group, *sid;
+
+ /* Don't attempt to fix clearly invalid security descriptors. */
+ if (size < sizeof(wimlib_SECURITY_DESCRIPTOR_RELATIVE))
+ return (u8*)_desc;
+
+ if (le16_to_cpu(desc->control) & wimlib_SE_DACL_PRESENT)
+ dacl_offset = le32_to_cpu(desc->dacl_offset);
+ else
+ dacl_offset = 0;
+
+ if (le16_to_cpu(desc->control) & wimlib_SE_SACL_PRESENT)
+ sacl_offset = le32_to_cpu(desc->sacl_offset);
+ else
+ sacl_offset = 0;
+
+ /* Check if the security descriptor will be affected by one of the bugs.
+ * If not, do nothing and return.
+ *
+ * Note: HAVE_NTFS_MNT_RDONLY is defined if libntfs-3g is
+ * version 2013.1.13 or later. */
+ if (!(
+ #if !defined(HAVE_NTFS_MNT_RDONLY)
+ (sacl_offset != 0 && sacl_offset == size - sizeof(wimlib_ACL)) ||
+ #endif
+ (dacl_offset != 0 && dacl_offset == size - sizeof(wimlib_ACL))))
+ return (u8*)_desc;
+
+ owner_offset = le32_to_cpu(desc->owner_offset);
+ group_offset = le32_to_cpu(desc->group_offset);
+ owner = (const wimlib_SID*)((const u8*)desc + owner_offset);
+ group = (const wimlib_SID*)((const u8*)desc + group_offset);
+
+ /* We'll try to move the owner or group SID to the end of the security
+ * descriptor to avoid the bug. This is only possible if at least one
+ * is valid. */
+ owner_valid = (owner_offset != 0) &&
+ (owner_offset % 4 == 0) &&
+ (owner_offset <= size - sizeof(SID)) &&
+ (owner_offset + sid_size(owner) <= size) &&
+ (owner_offset >= sizeof(wimlib_SECURITY_DESCRIPTOR_RELATIVE));
+ group_valid = (group_offset != 0) &&
+ (group_offset % 4 == 0) &&
+ (group_offset <= size - sizeof(SID)) &&
+ (group_offset + sid_size(group) <= size) &&
+ (group_offset >= sizeof(wimlib_SECURITY_DESCRIPTOR_RELATIVE));
+ if (owner_valid) {
+ sid = owner;
+ } else if (group_valid) {
+ sid = group;
+ } else {
+ return (u8*)_desc;
+ }
+
+ desc_new = MALLOC(size + sid_size(sid));
+ if (desc_new == NULL)
+ return (u8*)_desc;
+
+ memcpy(desc_new, desc, size);
+ if (owner_valid)
+ desc_new->owner_offset = cpu_to_le32(size);
+ else if (group_valid)
+ desc_new->group_offset = cpu_to_le32(size);
+ memcpy((u8*)desc_new + size, sid, sid_size(sid));
+ *size_p = size + sid_size(sid);
+ return (u8*)desc_new;
+}
+
static int
ntfs_3g_set_security_descriptor(const char *path, const u8 *desc, size_t desc_size,
struct apply_ctx *ctx)
ntfs_volume *vol;
ntfs_inode *ni;
struct SECURITY_CONTEXT sec_ctx;
- int ret = 0;
+ u8 *desc_fixed;
+ int ret;
vol = ntfs_3g_apply_ctx_get_volume(ctx);
memset(&sec_ctx, 0, sizeof(sec_ctx));
sec_ctx.vol = vol;
- if (ntfs_set_ntfs_acl(&sec_ctx, ni, desc, desc_size, 0))
+ desc_fixed = sd_fixup(desc, &desc_size);
+
+ ret = 0;
+
+ if (ntfs_set_ntfs_acl(&sec_ctx, ni, desc_fixed, desc_size, 0))
ret = WIMLIB_ERR_SET_SECURITY;
+
+ if (desc_fixed != desc)
+ FREE(desc_fixed);
+
if (ntfs_inode_close(ni))
ret = WIMLIB_ERR_WRITE;
+
return ret;
}
#include "wimlib/endianness.h"
#include "wimlib/error.h"
#include "wimlib/security.h"
+#include "wimlib/security_descriptor.h"
#include "wimlib/sha1.h"
#include "wimlib/util.h"
-/* At the start of each type of access control entry. */
-typedef struct _ACE_HEADER {
- /* enum ace_type, specifies what type of ACE this is. */
- u8 type;
-
- /* bitwise OR of the inherit ACE flags #defined above */
- u8 flags;
-
- /* Size of the access control entry. */
- le16 size;
-} _packed_attribute ACE_HEADER;
-
-/* Grants rights to a user or group */
-typedef struct _ACCESS_ALLOWED_ACE {
- ACE_HEADER hdr;
- le32 mask;
- le32 sid_start;
-} _packed_attribute ACCESS_ALLOWED_ACE;
-
-/* Denies rights to a user or group */
-typedef struct _ACCESS_DENIED_ACE {
- ACE_HEADER hdr;
- le32 mask;
- le32 sid_start;
-} _packed_attribute ACCESS_DENIED_ACE;
-
-typedef struct _SYSTEM_AUDIT_ACE {
- ACE_HEADER hdr;
- le32 mask;
- le32 sid_start;
-} _packed_attribute SYSTEM_AUDIT_ACE;
-
-
-/* Header of an access control list. */
-typedef struct _ACL {
- /* ACL_REVISION or ACL_REVISION_DS */
- u8 revision;
-
- /* padding */
- u8 sbz1;
-
- /* Total size of the ACL, including all access control entries */
- le16 acl_size;
-
- /* Number of access control entry structures that follow the ACL
- * structure. */
- le16 ace_count;
-
- /* padding */
- le16 sbz2;
-} _packed_attribute ACL;
-
-/* A structure used to identify users or groups. */
-typedef struct _SID {
-
- /* example: 0x1 */
- u8 revision;
- u8 sub_authority_count;
-
- /* Identifies the authority that issued the SID. Can be, but does not
- * have to be, one of enum sid_authority_value */
- u8 identifier_authority[6];
-
- le32 sub_authority[];
-} _packed_attribute SID;
-
-typedef struct _SECURITY_DESCRIPTOR_RELATIVE {
- /* Example: 0x1 */
- u8 revision;
- /* Example: 0x0 */
- u8 sbz1;
-
- /* Example: 0x4149 */
- le16 security_descriptor_control;
-
- /* Offset of a SID structure in the security descriptor. */
- /* Example: 0x14 */
- le32 owner_offset;
-
- /* Offset of a SID structure in the security descriptor. */
- /* Example: 0x24 */
- le32 group_offset;
-
- /* Offset of an ACL structure in the security descriptor. */
- /* System ACL. */
- /* Example: 0x00 */
- le32 sacl_offset;
-
- /* Offset of an ACL structure in the security descriptor. */
- /* Discretionary ACL. */
- /* Example: 0x34 */
- le32 dacl_offset;
-} _packed_attribute SECURITY_DESCRIPTOR_RELATIVE;
-
struct wim_security_data_disk {
le32 total_length;
le32 num_entries;
le64 sizes[];
} _packed_attribute;
-/*
- * This is a hack to work around a problem in libntfs-3g. libntfs-3g validates
- * security descriptors with a function named ntfs_valid_descr().
- * ntfs_valid_descr() considers a security descriptor that ends in a SACL
- * (Sysetm Access Control List) with no ACE's (Access Control Entries) to be
- * 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 this ensures that that the security descriptors pass
- * the validation in libntfs-3g.
- */
-static void
-empty_sacl_fixup(SECURITY_DESCRIPTOR_RELATIVE *descr, u64 *size_p)
-{
- /* No-op if no NTFS-3g support, or if NTFS-3g is version 2013 or later
- * */
-#if defined(WITH_NTFS_3G) && !defined(HAVE_NTFS_MNT_RDONLY)
- if (*size_p >= sizeof(SECURITY_DESCRIPTOR_RELATIVE)) {
- u32 sacl_offset = le32_to_cpu(descr->sacl_offset);
- if (sacl_offset == *size_p - sizeof(ACL)) {
- descr->sacl_offset = cpu_to_le32(0);
- *size_p -= sizeof(ACL);
- }
- }
-#endif
-}
-
struct wim_security_data *
new_wim_security_data(void)
{
if (!sd->descriptors[i])
goto out_of_memory;
p += sd->sizes[i];
- empty_sacl_fixup((SECURITY_DESCRIPTOR_RELATIVE*)sd->descriptors[i],
- &sd->sizes[i]);
}
out_align_total_length:
total_len = (total_len + 7) & ~7;
}
static void
-print_acl(const ACL *acl, const tchar *type, size_t max_size)
+print_acl(const wimlib_ACL *acl, const tchar *type, size_t max_size)
{
const u8 *p;
- if (max_size < sizeof(ACL))
+ if (max_size < sizeof(wimlib_ACL))
return;
u8 revision = acl->revision;
tprintf(T(" ACL Size = %u\n"), acl_size);
tprintf(T(" ACE Count = %u\n"), ace_count);
- p = (const u8*)acl + sizeof(ACL);
+ p = (const u8*)acl + sizeof(wimlib_ACL);
for (u16 i = 0; i < ace_count; i++) {
- if (max_size < p + sizeof(ACCESS_ALLOWED_ACE) - (const u8*)acl)
+ if (max_size < p + sizeof(wimlib_ACCESS_ALLOWED_ACE) - (const u8*)acl)
break;
- const ACCESS_ALLOWED_ACE *aaa = (const ACCESS_ALLOWED_ACE*)p;
+ const wimlib_ACCESS_ALLOWED_ACE *aaa = (const wimlib_ACCESS_ALLOWED_ACE*)p;
tprintf(T(" [ACE]\n"));
tprintf(T(" ACE type = %d\n"), aaa->hdr.type);
tprintf(T(" ACE flags = 0x%x\n"), aaa->hdr.flags);
}
static void
-print_sid(const SID *sid, const tchar *type, size_t max_size)
+print_sid(const wimlib_SID *sid, const tchar *type, size_t max_size)
{
- if (max_size < sizeof(SID))
+ if (max_size < sizeof(wimlib_SID))
return;
tprintf(T(" [%"TS" SID]\n"), type);
print_byte_field(sid->identifier_authority,
sizeof(sid->identifier_authority), stdout);
tputchar(T('\n'));
- if (max_size < sizeof(SID) + (size_t)sid->sub_authority_count * sizeof(u32))
+ if (max_size < sizeof(wimlib_SID) + (size_t)sid->sub_authority_count * sizeof(u32))
return;
for (u8 i = 0; i < sid->sub_authority_count; i++) {
tprintf(T(" Subauthority %u = %u\n"),
}
static void
-print_security_descriptor(const SECURITY_DESCRIPTOR_RELATIVE *descr,
+print_security_descriptor(const wimlib_SECURITY_DESCRIPTOR_RELATIVE *descr,
size_t size)
{
u8 revision = descr->revision;
- u16 control = le16_to_cpu(descr->security_descriptor_control);
+ u16 control = le16_to_cpu(descr->control);
u32 owner_offset = le32_to_cpu(descr->owner_offset);
u32 group_offset = le32_to_cpu(descr->group_offset);
u32 dacl_offset = le32_to_cpu(descr->dacl_offset);
tprintf(T("System ACL offset = %u\n"), sacl_offset);
if (owner_offset != 0 && owner_offset <= size)
- print_sid((const SID*)((const u8*)descr + owner_offset),
+ print_sid((const wimlib_SID*)((const u8*)descr + owner_offset),
T("Owner"), size - owner_offset);
if (group_offset != 0 && group_offset <= size)
- print_sid((const SID*)((const u8*)descr + group_offset),
+ print_sid((const wimlib_SID*)((const u8*)descr + group_offset),
T("Group"), size - group_offset);
if (dacl_offset != 0 && dacl_offset <= size)
- print_acl((const ACL*)((const u8*)descr + dacl_offset),
+ print_acl((const wimlib_ACL*)((const u8*)descr + dacl_offset),
T("Discretionary"), size - dacl_offset);
if (sacl_offset != 0 && sacl_offset <= size)
- print_acl((const ACL*)((const u8*)descr + sacl_offset),
+ print_acl((const wimlib_ACL*)((const u8*)descr + sacl_offset),
T("System"), size - sacl_offset);
}
for (u32 i = 0; i < sd->num_entries; i++) {
tprintf(T("[SECURITY_DESCRIPTOR_RELATIVE %"PRIu32", length = %"PRIu64"]\n"),
i, sd->sizes[i]);
- print_security_descriptor((const SECURITY_DESCRIPTOR_RELATIVE*)sd->descriptors[i],
+ print_security_descriptor((const wimlib_SECURITY_DESCRIPTOR_RELATIVE*)sd->descriptors[i],
sd->sizes[i]);
tputchar(T('\n'));
}