capability: add new type for maintaining all five cap sets as one

1 files changed, 24 insertions, 0 deletions

diff --git a/src/basic/capability-util.h b/src/basic/capability-util.h
index 59591d4b52..e0e0b1c0fa 100644
--- a/src/basic/capability-util.h
+++ b/src/basic/capability-util.h
@@ -43,3 +43,27 @@ bool ambient_capabilities_supported(void);
 /* Identical to linux/capability.h's CAP_TO_MASK(), but uses an unsigned 1U instead of a signed 1 for shifting left, in
  * order to avoid complaints about shifting a signed int left by 31 bits, which would make it negative. */
 #define CAP_TO_MASK_CORRECTED(x) (1U << ((x) & 31U))
+
+typedef struct CapabilityQuintet {
+        /* Stores all five types of capabilities in one go. Note that we use (uint64_t) -1 for unset here. This hence
+         * needs to be updated as soon as Linux learns more than 63 caps. */
+        uint64_t effective;
+        uint64_t bounding;
+        uint64_t inheritable;
+        uint64_t permitted;
+        uint64_t ambient;
+} CapabilityQuintet;
+
+assert_cc(CAP_LAST_CAP < 64);
+
+#define CAPABILITY_QUINTET_NULL { (uint64_t) -1, (uint64_t) -1, (uint64_t) -1, (uint64_t) -1, (uint64_t) -1 }
+
+static inline bool capability_quintet_is_set(const CapabilityQuintet *q) {
+        return q->effective != (uint64_t) -1 ||
+                q->bounding != (uint64_t) -1 ||
+                q->inheritable != (uint64_t) -1 ||
+                q->permitted != (uint64_t) -1 ||
+                q->ambient != (uint64_t) -1;
+}
+
+int capability_quintet_enforce(const CapabilityQuintet *q);