Expose checkpoint, revoke, reinstate and sweep on the CLI

sigil.py

@@ -5,7 +5,12 @@
     sigil.py keygen <path> [pass]               write an Ed25519 key (0600, encrypted if given)
     sigil.py enrol <agent> <pubkey.b64> <secret>
     sigil.py challenge <agent>                nonce to sign
-    sigil.py verify-chain                     check the audit log for tampering
+    sigil.py checkpoint <key> <agent> [label] sign the current audit head
+    sigil.py verify-chain                     check the chain and its checkpoints
+    sigil.py revoke <agent> [--until UNIX] [--reason R] [--actor A]
+                                         --until omitted means permanent
+    sigil.py reinstate <agent> [actor]       lift a revocation
+    sigil.py sweep                            prune stale nonces and rate rows
     sigil.py sign <keypath> <nonce> [pass]    signature, base64
     sigil.py verify <nonce> <sig.b64>         agent session token
     sigil.py code <agent> <keypath> [pass]    one-time code, proving the key
@@ -98,10 +103,71 @@ def main(argv) -> int:
             session["may_act_as_agent"] = may_act
             out(session)
 
+        elif cmd == "checkpoint":
+            # Signs the chain head with a key the database does not hold, which
+            # is what makes a later rewrite detectable.
+            if len(argv) < 4:
+                print("usage: sigil.py checkpoint <keypath> <agent> [label] [pass]")
+                return 2
+            private = keys.load_private(argv[2], argv[5] if len(argv) > 5 else None)
+            out(store.checkpoint(private, argv[3],
+                                 argv[4] if len(argv) > 4 else None))
+
         elif cmd == "verify-chain":
-            result = store.verify_chain()
-            out(result)
-            return 0 if result["ok"] else 1
+            chain = store.verify_chain()
+            anchors = store.verify_checkpoints()
+            out({"chain": chain, "checkpoints": anchors})
+            return 0 if chain["ok"] and anchors["ok"] else 1
+
+        elif cmd == "revoke":
+            # Positional optional args are a trap here: "revoke alice please"
+            # would otherwise try to parse "please" as a timestamp. Named flags
+            # are unambiguous, and a number only counts as a time if it parses.
+            allowed = {"until", "reason", "actor"}
+            flags, rest = {}, []
+            i = 2
+            while i < len(argv):
+                if argv[i].startswith("--"):
+                    key = argv[i][2:]
+                    if key not in allowed:
+                        print(f"unknown flag --{key}; expected one of "
+                              f"{', '.join('--' + a for a in sorted(allowed))}")
+                        return 2
+                    flags[key] = argv[i + 1] if i + 1 < len(argv) else ""
+                    i += 2
+                else:
+                    rest.append(argv[i])
+                    i += 1
+            if len(rest) != 1:
+                print("usage: sigil.py revoke <agent> [--until N] [--reason R]"
+                      " [--actor A]")
+                if rest:
+                    # Refusing beats guessing which agent was meant.
+                    print(f"expected exactly one agent name, got {rest}")
+                return 2
+            until = None
+            if "until" in flags:
+                try:
+                    until = int(flags["until"])
+                except ValueError:
+                    print(f"--until must be a unix timestamp, got {flags['until']!r}")
+                    return 2
+            killed = identity.revoke(
+                store, rest[0], until=until,
+                reason=flags.get("reason"),
+                actor=flags.get("actor", "system"),
+            )
+            out({"agent": rest[0], "revoked": True,
+                 "permanent": until is None, "sessions_revoked": killed})
+
+
+        elif cmd == "reinstate":
+            identity.reinstate(store, argv[2],
+                               argv[3] if len(argv) > 3 else "system")
+            out({"agent": argv[2], "revoked": False})
+
+        elif cmd == "sweep":
+            out(store.sweep())
 
         elif cmd == "events":
             out(store.events(argv[2] if len(argv) > 2 else None,