ctcloud: CertSpotter-backed CT cloud-resource monitor

Single stateless Go process that consumes CT logs via embedded (patched)
CertSpotter internals, classifies cloud/database/storage DNS identifiers
in-process with a zero-allocation classifier, enriches via round-robin DNS
resolvers with CNAME following, and batch-writes useful findings to PostgreSQL.

- third_party/certspotter: 2-hunk IdentifierSink patch, no stdout/JSON/files
- internal/classify: AWS/Azure/GCP/Firebase/Cloudflare R2/DigitalOcean/Supabase/OCI
- internal/dns: sharded bounded TTL cache, multi-resolver load balancing + failover
- internal/pipeline: bounded queues, dedup, direct-priority load shedding
- internal/store: pgx batch writer, Postgres CT checkpoints (no cert contents)
- internal/probe: optional non-destructive reachability checks (off by default)
- Docker: distroless non-root, read-only rootfs, no app volume, resource limits
- tests enforce 0 allocs/op on the classifier and sink hot path

third_party/certspotter/helpers_test.go

@@ -0,0 +1,49 @@
+// Copyright (C) 2016 Opsmate, Inc.
+//
+// This Source Code Form is subject to the terms of the Mozilla
+// Public License, v. 2.0. If a copy of the MPL was not distributed
+// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
+//
+// This software is distributed WITHOUT A WARRANTY OF ANY KIND.
+// See the Mozilla Public License for details.
+
+package certspotter
+
+import (
+	"testing"
+)
+
+func doWildcardTest(t *testing.T, dnsName string, wildcard string, expected bool) {
+	if MatchesWildcard(dnsName, wildcard) != expected {
+		t.Errorf("MatchesWildcard(%q, %q) != %v", dnsName, wildcard, expected)
+	}
+}
+
+func TestMatchesWildcard(t *testing.T) {
+	doWildcardTest(t, "", "", true)
+	doWildcardTest(t, "example.com", "example.com", true)
+	doWildcardTest(t, "example.org", "example.com", false)
+	doWildcardTest(t, "example.com", "", false)
+	doWildcardTest(t, "", "example.com", false)
+	doWildcardTest(t, "", "*.example.com", false)
+	doWildcardTest(t, "", "exam*ple.com", false)
+	doWildcardTest(t, "", "exam*ple.co*m", false)
+	doWildcardTest(t, "example.org", "example.com", false)
+	doWildcardTest(t, "example.org", "*.example.com", false)
+	doWildcardTest(t, "example.org", "exam*ple.com", false)
+	doWildcardTest(t, "example.org", "exam*ple.co*m", false)
+	doWildcardTest(t, "example.com", "*.example.com", false)
+	doWildcardTest(t, "www.example.com", "*.example.com", true)
+	doWildcardTest(t, "", "*", true)
+	doWildcardTest(t, "", "****", true)
+	doWildcardTest(t, "a", "****", true)
+	doWildcardTest(t, "a", "*", true)
+	doWildcardTest(t, "a", "****", true)
+	doWildcardTest(t, "abcd", "****", true)
+	doWildcardTest(t, "abcdef", "****", true)
+	doWildcardTest(t, "www-example.com", "*-example.com", true)
+	doWildcardTest(t, "www-example-www.com", "*-example-*.com", true)
+	doWildcardTest(t, "examplecom", "example*", true)
+	doWildcardTest(t, "example.com", "example*", false)
+	doWildcardTest(t, "examplea.com", "example*", false)
+}