feat: address Table C, D, and E feedback items (regex fixes, HMAC commitments, static sinks)

anchor/core/constitution.py

@@ -21,7 +21,7 @@
 
 # SHA-256 of the official legacy files (optional in V3).
 CONSTITUTION_SHA256 = "46539F9D069801C3ACA161696E9AF264299F8B578A510FEA3A28318A58ADC136"
-MITIGATION_SHA256 = "15554DB48B46C43816FA39B7E40F61F49975022058E6F1E264F2E2344B33409F"
+MITIGATION_SHA256 = "80489726A05A31933EA1448FA1E4AFB6E27A8B628E40EFD73B99535E1283DA32"
 
 
 # =============================================================================

anchor/governance/mitigation.anchor

@@ -82,7 +82,7 @@ mitigations:
       type: "regex"
       # Only fire on bulk access or sensitive key names
       pattern: >-
-        ^(?:[^"\'#]|(["\'])(?:(?!\1).|\\\1)*\1)*\bos\.(environ\.(copy|items)\(\)|\benviron\b\s*\[.*(?i)(TOKEN|KEY|SECRET|PASSWORD|CREDENTIAL|API).*\]|\{\*\*os\.environ)
+        (?i)^(?:[^"\'#]|(["\'])(?:(?!\1).|\\\1)*\1)*\bos\.(environ\.(copy|items)\(\)|\benviron\b\s*\[.*(TOKEN|KEY|SECRET|PASSWORD|CREDENTIAL|API).*\]|\{\*\*os\.environ)
     message: "Broad environment variable access detected. Agents may harvest secrets from env."
     severity: "error"
   # --- SEC-012: Governance Configuration Modification ---
@@ -96,3 +96,25 @@ mitigations:
         \.(write|save|update)\s*\(.*\.anchor["']
     message: "Unauthorized attempt to modify Anchor governance configuration detected. Governance state must be immutable at runtime."
     severity: "blocker"
+
+  # --- SEC-004: Hardcoded Secrets (Mitigation Catalog Extension) ---
+  - id: "MIT-004-B"
+    rule_id: "SEC-004"
+    name: "Hardcoded API Key / Secret"
+    match:
+      type: "regex"
+      pattern: >-
+        (?i)(?:[a-zA-Z0-9_]*key|[a-zA-Z0-9_]*secret|[a-zA-Z0-9_]*token|password|credential)\s*=\s*['\"][a-zA-Z0-9_\-\.\:\/]{16,}['\"]
+    message: "Hardcoded API key, secret, token or credential detected."
+    severity: "error"
+
+  # --- SEC-010: Insecure Python Execution ---
+  - id: "MIT-010-A"
+    rule_id: "SEC-010"
+    name: "Insecure Dynamic Python Execution Sinks"
+    match:
+      type: "regex"
+      pattern: >-
+        (?i)\b(?:eval|exec|pickle\.loads|pickle\.load|marshal\.loads|shelve\.open)\s*\(
+    message: "Dynamic python execution sink (eval/exec/pickle/marshal) detected."
+    severity: "error"

anchor/runtime/decision_auditor.py

@@ -261,7 +261,14 @@ def audit(self, provider: str, prompt: str, response: str, findings: list, juris
         timestamp = datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ")
         entry_id = str(uuid.uuid4())
         rule_ids = sorted([f.get("rule_id") for f in all_violations if f.get("rule_id")])
-        findings_hash = self._hash_payload(json.dumps(rule_ids))
+
+        # Salt the findings commitment to prevent offline dictionary enumeration
+        secret_key = os.environ.get("ANCHOR_MAT", os.environ.get("ANCHOR_SECRET_KEY", "default-key")).strip()
+        findings_hash = hmac.new(
+            secret_key.encode("utf-8"),
+            (json.dumps(rule_ids) + entry_id).encode("utf-8"),
+            hashlib.sha256
+        ).hexdigest()
 
         prev_hash = self.get_last_runtime_hash()
         chain_hash = self._hash_payload(prev_hash + findings_hash)

tests/unit/test_feedback_fixes.py

@@ -0,0 +1,65 @@
+import re
+import hmac
+import hashlib
+import json
+from unittest.mock import patch, MagicMock
+from anchor.runtime.decision_auditor import DecisionAuditor
+from anchor.runtime.models import AuditEntry
+
+def test_sec_004_regex_compilation():
+    # Verify that the SEC-004 regex pattern compiles and executes without errors in Python
+    # (Checking the fix for "global flags not at the start of the expression")
+    pattern = r"(?i)^(?:[^\"\'#]|([\"'])(?:(?!\1).|\\\1)*\1)*\bos\.(environ\.(copy|items)\(\)|\benviron\b\s*\[.*(TOKEN|KEY|SECRET|PASSWORD|CREDENTIAL|API).*\]|\{\*\*os\.environ)"
+
+    # Try compiling
+    compiled = re.compile(pattern)
+    assert compiled is not None
+
+    # Try matching
+    match_str = "os.environ['API_KEY']"
+    assert compiled.search(match_str) is not None
+
+def test_findings_hash_salting():
+    # Verify that findings_hash is computed using HMAC-SHA256 and salted with entry_id
+    # (So same rules with different entry_ids produce different findings_hash)
+    auditor = DecisionAuditor()
+
+    # Mock runtime chain hash retrieval
+    auditor.get_last_runtime_hash = MagicMock(return_value="0".zfill(64))
+
+    # Run audit 1
+    entry1 = auditor.audit(
+        provider="test-provider",
+        prompt="test prompt",
+        response="test response",
+        findings=[{"rule_id": "SEC-004"}]
+    )
+
+    # Run audit 2 with same rules/inputs
+    entry2 = auditor.audit(
+        provider="test-provider",
+        prompt="test prompt",
+        response="test response",
+        findings=[{"rule_id": "SEC-004"}]
+    )
+
+    # Verify entry_ids are different
+    assert entry1["entry_id"] != entry2["entry_id"]
+
+    # Verify findings_hashes are different (due to entry_id salting)
+    assert entry1["cryptography"]["findings_hash"] != entry2["cryptography"]["findings_hash"]
+
+def test_static_detectors_mitigations():
+    # Test MIT-004-B (Hardcoded API Key / Secret) regex matches
+    mit_004_b_pattern = r"(?i)(?:[a-zA-Z0-9_]*key|[a-zA-Z0-9_]*secret|[a-zA-Z0-9_]*token|password|credential)\s*=\s*['\"][a-zA-Z0-9_\-\.\:\/]{16,}['\"]"
+    rx_004 = re.compile(mit_004_b_pattern)
+    assert rx_004.search("openai_key = 'sk-proj-1234567890abcdef1234567890'") is not None
+    assert rx_004.search("secret_key = \"mysecretkey12345\"") is not None
+    assert rx_004.search("api-key = '12345'") is None # Too short (<16 chars)
+
+    # Test MIT-010-A (Insecure Python Execution sinks) regex matches
+    mit_010_a_pattern = r"(?i)\b(?:eval|exec|pickle\.loads|pickle\.load|marshal\.loads|shelve\.open)\s*\("
+    rx_010 = re.compile(mit_010_a_pattern)
+    assert rx_010.search("eval(user_code)") is not None
+    assert rx_010.search("pickle.loads(payload)") is not None
+    assert rx_010.search("other_func()") is None