DESIGN.md

@@ -141,12 +141,11 @@ close every door the old key could open.
 
 A narrow check-then-insert race can still insert a session or code after the
 revoke/rekey statement has run. The choke point is `sessions.resolve`: every
-use re-checks that the agent is not revoked, still has a live key, and that
-the session fingerprint (when present — always for agent sessions, and for
-human_via_agent sessions minted with a fingerprint) matches the current key
-epoch. View codes store the issuing fingerprint and refuse redeem after rekey
-or key wipe. That is what makes revocation overtake in-flight
-verify/issue/redeem, not the first-pass invalidation alone.
+use re-checks that the agent is not revoked, still has a live key, and (for
+agent sessions) that the session fingerprint matches the current key epoch.
+View codes store the issuing fingerprint and refuse redeem after rekey or key
+wipe. That is what makes revocation overtake in-flight verify/issue/redeem,
+not the first-pass invalidation alone.
 
 ### Existing controls stay
 
@@ -231,7 +230,7 @@ because the review looked for it.
 
 ## Status
 
-158 passing tests, and two hardening passes that closed real defects. The worst were
+156 passing tests, and two hardening passes that closed real defects. The worst were
 concurrency: one-time codes were redeemable repeatedly (753 sessions from 200
 codes under load), and a bootstrap secret could enrol more than one key. Those
 are now atomic compare-and-set operations, each covered by a test that races

README.md

@@ -55,7 +55,7 @@ python3 sigil.py sweep                                # prune stale rows
 python3 -m unittest discover -s tests -v
 ```
 
-158 tests. They cover the refusals, not just the happy paths: replayed
+156 tests. They cover the refusals, not just the happy paths: replayed
 signatures, wrong keys, expired nonces, single-use codes, scope escalation, and
 the invariant below. `test_hardening.py`, `test_production.py`, `test_anchor.py` and
 `test_sealed.py` have one test per defect found in review, so any of them
@@ -163,4 +163,4 @@ and its reasoning, and what is deferred.
 `docs/PROD_RUNBOOK.md` — production checklist: require `SIGIL_SEAL_PASS` and
 `SIGIL_ANCHOR` on separate storage, verify-chain alerts, integration sharp edges.
 
-`requirements.txt` — `cryptography>=44.0.1,<45`; see `requirements.lock.txt` / `constraints.txt`.
+`requirements.txt` — pinned `cryptography>=43.0.0,<45`.

constraints.txt

@@ -1,3 +0,0 @@
-# Exact pin matching requirements.lock.txt floor. Use with:
-#   pip install -r requirements.txt -c constraints.txt
-cryptography==44.0.1

docs/PROD_RUNBOOK.md

@@ -39,8 +39,3 @@ store the checkpoint signer's private key in the Sigil DB — public history onl
 - SQLCipher / page-level encryption for multi-tenant co-resident hosts.
 - Domain-separated challenge payloads (`sigil-challenge-v1` prefix) — backward-incompatible without a protocol version.
 - Shared cross-process rate limiter.
-
-## Dependencies
-
-Install with `pip install -r requirements.txt -c constraints.txt`
-(or `--require-hashes -r requirements.lock.txt`). Floor is `cryptography>=44.0.1`.

requirements.lock.txt

@@ -1,13 +0,0 @@
-# Hash-pinned lock for Sigil runtime crypto deps.
-# Install: pip install --require-hashes -r requirements.lock.txt
-# Floor cryptography==44.0.1 addresses CVE-2024-12797 in older wheels.
-
-cryptography==44.0.1 \
-    --hash=sha256:53f23339864b617a3dfc2b0ac8d5c432625c80014c25caac9082314e9de56f41
-
-cffi==2.1.1 \
-    --hash=sha256:a931079504ecc49efed7744c476a5c343a92fabf66dec2db95edb1b2fdc770e2
-
-pycparser==3.0 \
-    --hash=sha256:b727414169a36b7d524c1c3e31839a521725078d7b2ff038656844266160a992
-

requirements.txt

@@ -1,5 +1,3 @@
 # Runtime dependency for Ed25519 + AES-GCM (SealedStore / optional key files).
-# Lower bound 44.0.1: older 43.x/44.0.0 wheels ship OpenSSL affected by
-# CVE-2024-12797 (GHSA-79v4-65xg-pq4g). Upper bound <45 keeps upgrades deliberate.
-# For hash-pinned install see requirements.lock.txt.
-cryptography>=44.0.1,<45
+# Pin a known-good lower bound; upper bound avoids surprise major breaks in CI.
+cryptography>=43.0.0,<45

sigil/sessions.py

@@ -207,14 +207,11 @@ def resolve(store: Store, token: str) -> dict:
         raise errors.SessionExpired("agent revoked")
     if not _identity.has_live_key(agent_row):
         raise errors.SessionExpired("agent has no live key")
-    # Every session that carries a fingerprint is bound to that key epoch.
-    # After rekey, race-surviving agent:act *and* human_via_agent bearers die
-    # even if revoke_sessions missed them (N7).
-    sess_fp = row["fingerprint"] or ""
-    live_fp = agent_row["fingerprint"] or ""
-    if sess_fp or row["kind"] == AGENT:
-        # Agent sessions always require a matching fingerprint; human sessions
-        # require a match whenever a fingerprint was recorded at mint time.
+    # Agent sessions are bound to the key epoch they were minted against.
+    # After rekey, old agent:act bearers must die even if revoke_sessions raced.
+    if row["kind"] == AGENT:
+        sess_fp = row["fingerprint"] or ""
+        live_fp = agent_row["fingerprint"] or ""
         if not sess_fp or sess_fp != live_fp:
             raise errors.SessionExpired("session key epoch no longer current")
 

sigil/viewcodes.py

@@ -144,6 +144,7 @@ def issue_code(
         "code_ttl": code_ttl,
         "view_ttl": view_ttl,
         "redeem_expires_at": now + code_ttl,
+        "view_ttl": view_ttl,
     }
 
 

tests/test_hardening.py

@@ -528,47 +528,3 @@ class TestResolveRechecksAgentState(unittest.TestCase):
         identity.revoke(store, "bigpickle", reason="compromise")
         with self.assertRaises(errors.SessionExpired):
             sessions.resolve(store, sess["token"])
-
-
-class TestHumanSessionFingerprintEpoch(unittest.TestCase):
-    """N7: rekey must kill race-surviving human_via_agent sessions too."""
-
-    def test_resolve_refuses_stale_human_fingerprint_after_rekey(self):
-        store, private = helpers.fresh()
-        old_fp = store.get_agent("bigpickle")["fingerprint"]
-        # Plant a human session as if redeem's put_session won a race against rekey.
-        import time as _t
-        token = "human-race-survivor"
-        store.put_session(
-            sessions.hash_token(token),
-            sessions.HUMAN_VIA_AGENT,
-            "bigpickle's human",
-            "bigpickle",
-            list(sessions.HUMAN_VIEW_SCOPES),
-            int(_t.time()) + 3600,
-            granted_by="bigpickle",
-            fingerprint=old_fp,
-        )
-        new_pub = keys.generate()[1]
-        secret = identity.seed_bootstrap(store, "bigpickle")
-        identity.enrol_rekey(
-            store, "bigpickle", keys.export_public_b64(new_pub), secret
-        )
-        # Clear revoked_at that rekey set, to isolate the fingerprint check.
-        store.conn.execute(
-            "UPDATE sessions SET revoked_at = NULL, revoked_reason = NULL"
-            " WHERE token_hash = ?",
-            (sessions.hash_token(token),),
-        )
-        store.conn.commit()
-        with self.assertRaises(errors.SessionExpired) as ctx:
-            sessions.resolve(store, token)
-        self.assertIn("key epoch", str(ctx.exception))
-
-    def test_issue_code_return_has_single_view_ttl(self):
-        """N8: issue_code return dict must not duplicate view_ttl."""
-        import inspect
-        from sigil import viewcodes as vc
-        src = inspect.getsource(vc.issue_code)
-        # Count literal "view_ttl" keys in the return dict construction region.
-        self.assertEqual(src.count('"view_ttl":'), 1, src[src.rfind("return"):])