Allow block and char classes in DeviceAllow bus properties (#4353)

Allowed paths are unified betwen the configuration file parses and the bus
property checker. The biggest change is that the bus code now allows "block-"
and "char-" classes. In addition, path_startswith("/dev") was used in the bus
code, and startswith("/dev") was used in the config file code. It seems
reasonable to use path_startswith() which allows a slightly broader class of
strings.

Fixes #3935.

2 files changed, 9 insertions, 3 deletions

diff --git a/src/basic/path-util.c b/src/basic/path-util.c
index c32e961af4..a76963aa9f 100644
--- a/src/basic/path-util.c
+++ b/src/basic/path-util.c
@@ -812,9 +812,14 @@ bool is_device_path(const char *path) {
         /* Returns true on paths that refer to a device, either in
          * sysfs or in /dev */
 
-        return
-                path_startswith(path, "/dev/") ||
-                path_startswith(path, "/sys/");
+        return path_startswith(path, "/dev/") ||
+               path_startswith(path, "/sys/");
+}
+
+bool is_deviceallow_pattern(const char *path) {
+        return path_startswith(path, "/dev/") ||
+               startswith(path, "block-") ||
+               startswith(path, "char-");
 }
 
 int systemd_installation_has_version(const char *root, unsigned minimal_version) {
diff --git a/src/basic/path-util.h b/src/basic/path-util.h
index 78472f0961..66545f52d9 100644
--- a/src/basic/path-util.h
+++ b/src/basic/path-util.h
@@ -125,5 +125,6 @@ char *file_in_same_dir(const char *path, const char *filename);
 bool hidden_or_backup_file(const char *filename) _pure_;
 
 bool is_device_path(const char *path);
+bool is_deviceallow_pattern(const char *path);
 
 int systemd_installation_has_version(const char *root, unsigned minimal_version);