Update OTA installer to understand SELinux filesystem labels

Modify the OTA installer to understand SELinux filesystem labels.

We do this by introducing new set_perm2 / set_perm2_recursive
calls, which understand SELinux filesystem labels. These filesystem
labels are applied at the same time that we apply the
UID / GID / permission changes.

For compatibility, we preserve the behavior of the existing
set_perm / set_perm_recursive calls.

If the destination kernel doesn't support security labels, don't
fail. SELinux isn't enabled on all kernels.

Bug: 8985290
Change-Id: I99800499f01784199e4918a82e3e2db1089cf25b

2 files changed, 8 insertions, 3 deletions

diff --git a/minzip/DirUtil.c b/minzip/DirUtil.c
index 8dd5da1..c120fa3 100644
--- a/minzip/DirUtil.c
+++ b/minzip/DirUtil.c
@@ -23,6 +23,7 @@
 #include <errno.h>
 #include <dirent.h>
 #include <limits.h>
+#include <selinux/selinux.h>
 
 #include "DirUtil.h"
 
@@ -237,7 +238,7 @@ dirUnlinkHierarchy(const char *path)
 
 int
 dirSetHierarchyPermissions(const char *path,
-        int uid, int gid, int dirMode, int fileMode)
+        int uid, int gid, int dirMode, int fileMode, const char* secontext)
 {
     struct stat st;
     if (lstat(path, &st)) {
@@ -255,6 +256,10 @@ dirSetHierarchyPermissions(const char *path,
         return -1;
     }
 
+    if ((secontext != NULL) && lsetfilecon(path, secontext) && (errno != ENOTSUP)) {
+        return -1;
+    }
+
     /* recurse over directory components */
     if (S_ISDIR(st.st_mode)) {
         DIR *dir = opendir(path);
@@ -271,7 +276,7 @@ dirSetHierarchyPermissions(const char *path,
 
             char dn[PATH_MAX];
             snprintf(dn, sizeof(dn), "%s/%s", path, de->d_name);
-            if (!dirSetHierarchyPermissions(dn, uid, gid, dirMode, fileMode)) {
+            if (!dirSetHierarchyPermissions(dn, uid, gid, dirMode, fileMode, secontext)) {
                 errno = 0;
             } else if (errno == 0) {
                 errno = -1;
diff --git a/minzip/DirUtil.h b/minzip/DirUtil.h
index a5cfa76..3e12a0b 100644
--- a/minzip/DirUtil.h
+++ b/minzip/DirUtil.h
@@ -54,7 +54,7 @@ int dirUnlinkHierarchy(const char *path);
  * Sets directories to <dirMode> and files to <fileMode>.  Skips symlinks.
  */
 int dirSetHierarchyPermissions(const char *path,
-         int uid, int gid, int dirMode, int fileMode);
+         int uid, int gid, int dirMode, int fileMode, const char* secontext);
 
 #ifdef __cplusplus
 }