X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2Flibadacl.c;h=30a39f2704883a60429abd279a05c99caeb9b0c9;hb=b13aa67306336a89d9947735622c547c13acffb6;hp=d92432228358badf66a302e34e31ff459579b1de;hpb=c5fdaba07b5f965edca0a57d9c3cd8f8bbabc155;p=apply-default-acl.git

diff --git a/src/libadacl.c b/src/libadacl.c
index d924322..30a39f2 100644
--- a/src/libadacl.c
+++ b/src/libadacl.c
@@ -69,7 +69,7 @@ int safe_open_ex(int at_fd, char* pathname, int flags) {
     /* No more slashes, this is the base case. */
     return openat(at_fd, pathname, flags);
   }
-  else if (firstslash[1] == '\0') {
+  if (firstslash[1] == '\0') {
     /* The first slash is the last character; ensure that we open
        a directory. */
     firstslash[0] = '\0';
@@ -127,7 +127,7 @@ int safe_open_ex(int at_fd, char* pathname, int flags) {
  *   and @c OPEN_ERROR if not.
  */
 int safe_open(const char* pathname, int flags) {
-  if (pathname == NULL || strlen(pathname) == 0 || pathname[0] == '\0') {
+  if (pathname == NULL) {
     errno = EINVAL;
     perror("safe_open (args)");
     return OPEN_ERROR;
@@ -681,6 +681,30 @@ int acl_copy_xattr(int src_fd,
 }
 
 
+/**
+ * @brief Determine if a file descriptor has a default ACL.
+ *
+ * @param fd
+ *   The file descriptor whose default ACL is in question.
+ *
+ * @return
+ *   - @c ACL_SUCCESS - If @c fd has a default ACL.
+ *   - @c ACL_FAILURE - If @c fd does not have a default ACL.
+ *   - @c ACL_ERROR - Unexpected library error.
+ */
+int has_default_acl_fd(int fd) {
+  if (fgetxattr(fd, XATTR_NAME_POSIX_ACL_DEFAULT, NULL, 0) == XATTR_ERROR) {
+    if (errno == ENODATA) {
+      return ACL_FAILURE;
+    }
+    perror("has_default_acl_fd (fgetxattr)");
+    return ACL_ERROR;
+  }
+
+  return ACL_SUCCESS;
+}
+
+
 /**
  * @brief Apply parent default ACL to a path.
  *
@@ -754,6 +778,13 @@ int apply_default_acl_ex(const char* path,
     }
   }
 
+  /* Check to make sure the parent descriptor actually has a default
+     ACL. If it doesn't, then we can "succeed" immediately. */
+  if (has_default_acl_fd(parent_fd) == ACL_FAILURE) {
+    result = ACL_SUCCESS;
+    goto cleanup;
+  }
+
   fd = safe_open(path, O_NOFOLLOW);
   if (fd == OPEN_ERROR) {
     if (errno == ELOOP || errno == ENOTDIR) {
@@ -858,7 +889,13 @@ int apply_default_acl_ex(const char* path,
   */
 
   /* Now we potentially need to mask the execute permissions in the
-     ACL on fd. First obtain the current one... */
+     ACL on fd; or maybe now. */
+  if (allow_exec) {
+    goto cleanup;
+  }
+
+  /* OK, we need to mask some execute permissions. First obtain the
+     current ACL... */
   new_acl = acl_get_fd(fd);
   if (new_acl == (acl_t)NULL) {
     perror("apply_default_acl_ex (acl_get_fd)");
@@ -902,21 +939,19 @@ int apply_default_acl_ex(const char* path,
         tag == ACL_GROUP_OBJ ||
         tag == ACL_OTHER) {
 
-      if (!allow_exec) {
-        /* The mask doesn't affect acl_user_obj, acl_group_obj (in
-           minimal ACLs) or acl_other entries, so if execute should be
-           masked, we have to do it manually. */
-        if (acl_delete_perm(permset, ACL_EXECUTE) == ACL_ERROR) {
-          perror("apply_default_acl_ex (acl_delete_perm)");
-          result = ACL_ERROR;
-          goto cleanup;
-        }
-
-        if (acl_set_permset(entry, permset) == ACL_ERROR) {
-          perror("apply_default_acl_ex (acl_set_permset)");
-          result = ACL_ERROR;
-          goto cleanup;
-        }
+      /* The mask doesn't affect acl_user_obj, acl_group_obj (in
+         minimal ACLs) or acl_other entries, so if execute should be
+         masked, we have to do it manually. */
+      if (acl_delete_perm(permset, ACL_EXECUTE) == ACL_ERROR) {
+        perror("apply_default_acl_ex (acl_delete_perm)");
+        result = ACL_ERROR;
+        goto cleanup;
+      }
+
+      if (acl_set_permset(entry, permset) == ACL_ERROR) {
+        perror("apply_default_acl_ex (acl_set_permset)");
+        result = ACL_ERROR;
+        goto cleanup;
       }
     }