From 7865203fee68dcdfa39ab037c31db9583b3a66bc Mon Sep 17 00:00:00 2001
From: Leopold Joy <leo@leopoldjoy.com>
Date: Fri, 24 Jul 2026 21:33:19 +0100
Subject: [PATCH] fix: validate cached ancestor expiry

Co-authored-by: OpenCode <opencode-noreply@coinbase.com>
---
 src/CertManager.sol    |  4 +++-
 test/CertManager.t.sol | 26 ++++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/src/CertManager.sol b/src/CertManager.sol
index 29ecfd0..6a38a80 100644
--- a/src/CertManager.sol
+++ b/src/CertManager.sol
@@ -244,6 +244,9 @@ contract CertManager is ICertManager {
     function _requireCachedChainNotRevoked(bytes32 certHash) internal view {
         while (certHash != bytes32(0)) {
             _requireNotRevoked(_revocationKey(certHash));
+            VerifiedCert memory cert = _loadVerified(certHash);
+            if (cert.pubKey.length == 0) revert IncompleteCertChain();
+            require(!_certificateExpired(cert.notAfter), "cert expired");
             if (certHash == ROOT_CA_CERT_HASH) {
                 return;
             }
@@ -267,7 +270,6 @@ contract CertManager is ICertManager {
             parent = _loadVerified(parentCertHash);
             require(parent.pubKey.length > 0, "parent cert unverified");
             _requireCachedChainNotRevoked(parentCertHash);
-            require(!_certificateExpired(parent.notAfter), "parent cert expired");
             require(parent.ca, "parent cert is not a CA");
             require(!ca || parent.maxPathLen != 0, "maxPathLen exceeded");
         }
diff --git a/test/CertManager.t.sol b/test/CertManager.t.sol
index 6db1293..33426e7 100644
--- a/test/CertManager.t.sol
+++ b/test/CertManager.t.sol
@@ -635,6 +635,13 @@ contract RevocationChainHarness is CertManager {
         verifiedParent[child] = parent;
     }
 
+    function setCachedCert(bytes32 certHash, uint64 notAfter) external {
+        _saveVerified(
+            certHash,
+            VerifiedCert({ca: true, notAfter: notAfter, maxPathLen: -1, subjectHash: bytes32(0), pubKey: new bytes(96)})
+        );
+    }
+
     function requireCachedChainNotRevoked(bytes32 certHash) external view {
         _requireCachedChainNotRevoked(certHash);
     }
@@ -655,15 +662,34 @@ contract RequireCachedChainNotRevokedTest is Test {
 
     function test_PassesWhenChainReachesPinnedRoot() public {
         bytes32 root = cm.ROOT_CA_CERT_HASH();
+        cm.setCachedCert(CHILD, type(uint64).max);
+        cm.setCachedCert(PARENT, type(uint64).max);
         cm.setParent(CHILD, PARENT);
         cm.setParent(PARENT, root);
         // Walks CHILD -> PARENT -> ROOT and returns without reverting.
         cm.requireCachedChainNotRevoked(CHILD);
     }
 
+    function test_RevertsWhenCachedGrandparentIsExpired() public {
+        vm.warp(1000);
+        bytes32 grandparent = bytes32(uint256(3));
+
+        cm.setCachedCert(CHILD, 2000);
+        cm.setCachedCert(PARENT, 2000);
+        cm.setCachedCert(grandparent, 999);
+        cm.setParent(CHILD, PARENT);
+        cm.setParent(PARENT, grandparent);
+        cm.setParent(grandparent, cm.ROOT_CA_CERT_HASH());
+
+        vm.expectRevert("cert expired");
+        cm.requireCachedChainNotRevoked(CHILD);
+    }
+
     function test_RevertsWhenChainDoesNotReachRoot() public {
         // verifiedParent[PARENT] is unset (bytes32(0)), so the chain is broken: it can never
         // reach ROOT_CA_CERT_HASH. The fixed function must fail closed instead of returning.
+        cm.setCachedCert(CHILD, type(uint64).max);
+        cm.setCachedCert(PARENT, type(uint64).max);
         cm.setParent(CHILD, PARENT);
         vm.expectRevert(CertManager.IncompleteCertChain.selector);
         cm.requireCachedChainNotRevoked(CHILD);