wimfs_readlink(): Use wim_pathname_to_inode()

[wimlib] / src / security.c

diff --git a/src/security.c b/src/security.c
index 8fda950c6261f26e99832723921ff0272e969cd3..fef6043af2fdc0f5910f2c816aaf68b16ffe9c42 100644 (file)
--- a/src/security.c
+++ b/src/security.c
@@ -1,8 +1,9 @@
 /*
  * security.c
  *
- * Read the security data from the WIM.  Doing anything with the security data
- * is not yet implemented other than printing some information about it.
+ * Read and write the WIM security data.  The security data is a table of
+ * security descriptors. Each WIM image has its own security data, but it's
+ * possible that an image's security data have no security descriptors.
  */
 
 /*
@@ -11,16 +12,16 @@
  * This file is part of wimlib, a library for working with WIM files.
  *
  * 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)
+ * terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or (at your option)
  * any later version.
  *
  * 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
+ * A PARTICULAR PURPOSE. See the GNU General Public License for more
  * details.
  *
- * You should have received a copy of the GNU Lesser General Public License
+ * You should have received a copy of the GNU General Public License
  * along with wimlib; if not, see http://www.gnu.org/licenses/.
  */
 
@@ -28,6 +29,29 @@
 #include "io.h"
 #include "security.h"
 
+/* 
+ * 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  his ensures that that the security descriptors pass
+ * the validation in libntfs-3g.
+ */
+static void empty_sacl_fixup(char *descr, u64 *size_p)
+{
+       if (*size_p >= sizeof(SecurityDescriptor)) {
+               SecurityDescriptor *sd = (SecurityDescriptor*)descr;
+               u32 sacl_offset = le32_to_cpu(sd->sacl_offset);
+               if (sacl_offset == *size_p - sizeof(ACL)) {
+                       sd->sacl_offset = to_le32(0);
+                       *size_p -= sizeof(ACL);
+               }
+       }
+}
+
 /* 
  * Reads the security data from the metadata resource.
  *
@@ -150,6 +174,7 @@ int read_security_data(const u8 metadata_resource[], u64 metadata_resource_len,
                        goto out_free_sd;
                }
                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;