feat(transport): add transport-neutral MCP bind seam
Closes #931.
The transport was a literal passed once at the bottom of the module,
bind_native_mcp_transport(transport="stdio"), and every guard that asks
"is this a trusted native session" resolves that question through the
value bound there. The string was a constant in the authorization chain
rather than configuration, so a remote transport had no way to be
expressed and no way to be told apart from an untrusted offline import.
mcp_transport_config becomes the single source of truth: it owns the
permitted set, the default, and the resolution of deployment
configuration (GITEA_MCP_TRANSPORT) into a validated identifier. Unset
configuration still yields stdio, so existing deployments are unchanged.
streamable-http is accepted so the bind is pluggable; standing up its
listener remains #938. sse is deliberately not registered.
bind_native_mcp_transport now resolves from configuration when no
transport argument is given, validates against that one permitted set
before writing the runtime record, and pins the result. bound_transport
is the shared accessor every transport-aware guard reads; it reports the
pinned value and never the environment, so a post-bind GITEA_MCP_TRANSPORT
change cannot move what a guard observes -- the rule already applied to
the session-state root under #695 AC2. Rebinding the same identifier is
idempotent; rebinding a different one is refused, so two guards can never
disagree within one process. assert_transport_bound fails closed before
mcp.run, so an absent or invalid bind stops the server instead of serving
tools over a transport no guard can name.
The bound identifier is now recorded in durable provenance:
mutation_provenance_fields gains bound_transport, which reaches the
decision lock through mcp_session_state.save_state and the audit records
that already spread those fields. The pre-existing transport field keeps
its trust-class values, so no durable record changes shape.
assess_transport_for_auth_mint reports the bound transport through the
same accessor; its verdict is unchanged.
#956's anchor fixture and threat model are re-anchored for the lines this
change shifts, and the two boundary claims that #931 makes false -- the
"literal stdio bind" in B1 and the stdio contract at mcp_server.py:4 --
are restated. Without this the #956 guard fails, which is what it is for.
Non-goals, untouched: the remote listener (#938), per-request principal
resolution (#932), client-managed provenance policy (#934), TLS and
remote client authentication, role capability sets, repository-binding
semantics.
Tests: tests/test_issue_931_transport_bind_seam.py, 42 tests, covering
default bind, explicit stdio, the accepted non-stdio identifier, an
unregistered identifier, no bind at all, one-value agreement across
guards, post-bind environment tampering, the durable decision-lock
record, the rebind contract, and the #695 protections that must not
regress.
Full suite from the branches/ worktree: 28 failed, 5843 passed, 6
skipped, 1047 subtests. The pinned base 9b80e75c reports 28 failed, 5801
passed, 6 skipped, 1047 subtests. The failing test IDs are identical sets
-- no failure added, none fixed; the +42 passed are this PR's new module.
Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>
This commit is contained in:
Claude Opus 4.8
@@ -10,21 +10,21 @@
|
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],
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"generated_against_commit": "aad5c8b42361d380a8eeb07b94b90815e594c2c5",
|
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"anchors": [
|
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{"anchor": "gitea_mcp_server.py:24721", "expect": "bind_native_mcp_transport(transport=\"stdio\")"},
|
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{"anchor": "mcp_daemon_guard.py:45", "expect": "_PRODUCTION_TRANSPORTS = frozenset({\"stdio\"})"},
|
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{"anchor": "mcp_daemon_guard.py:174", "expect": "def bind_native_mcp_transport"},
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{"anchor": "gitea_mcp_server.py:24728", "expect": "mcp_daemon_guard.bind_native_mcp_transport()"},
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{"anchor": "mcp_daemon_guard.py:49", "expect": "_PRODUCTION_TRANSPORTS = mcp_transport_config.SUPPORTED_TRANSPORTS"},
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{"anchor": "mcp_daemon_guard.py:178", "expect": "def bind_native_mcp_transport"},
|
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{"anchor": "irrecoverable_provenance.py:497", "expect": "def assess_transport_for_auth_mint"},
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{"anchor": "gitea_mcp_server.py:9129", "expect": "assess_transport_for_auth_mint()"},
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{"anchor": "gitea_mcp_server.py:9378", "expect": "assess_transport_for_auth_mint()"},
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{"anchor": "mcp_server.py:4", "expect": "Runs over stdio."},
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{"anchor": "gitea_mcp_server.py:9132", "expect": "assess_transport_for_auth_mint()"},
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{"anchor": "gitea_mcp_server.py:9381", "expect": "assess_transport_for_auth_mint()"},
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{"anchor": "mcp_server.py:4", "expect": "The transport is selected by deployment configuration"},
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{"anchor": "gitea_mcp_server.py:15412", "expect": "def _is_client_managed_process"},
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{"anchor": "gitea_mcp_server.py:15442", "expect": "def _provenance_mutation_block"},
|
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{"anchor": "gitea_mcp_server.py:15450", "expect": "unsupported_manual_launch"},
|
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{"anchor": "gitea_mcp_server.py:19001", "expect": "server_provenance"},
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{"anchor": "gitea_mcp_server.py:21442", "expect": "def _check_mcp_runtimes_diagnostics"},
|
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{"anchor": "gitea_mcp_server.py:21462", "expect": "\"ps\", \"-o\", \"pid,lstart,command\""},
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{"anchor": "gitea_mcp_server.py:21506", "expect": "\"ps\", \"eww\""},
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{"anchor": "gitea_mcp_server.py:15415", "expect": "def _is_client_managed_process"},
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{"anchor": "gitea_mcp_server.py:15445", "expect": "def _provenance_mutation_block"},
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{"anchor": "gitea_mcp_server.py:15453", "expect": "unsupported_manual_launch"},
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{"anchor": "gitea_mcp_server.py:19004", "expect": "server_provenance"},
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{"anchor": "gitea_mcp_server.py:21445", "expect": "def _check_mcp_runtimes_diagnostics"},
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{"anchor": "gitea_mcp_server.py:21465", "expect": "\"ps\", \"-o\", \"pid,lstart,command\""},
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{"anchor": "gitea_mcp_server.py:21509", "expect": "\"ps\", \"eww\""},
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{"anchor": "gitea_config.py:1172", "expect": "RECOGNIZED_GITEA_ENV_KEYS"},
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{"anchor": "gitea_config.py:1233", "expect": "GITEA_CLIENT_MANAGED"},
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@@ -36,19 +36,19 @@
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{"anchor": "gitea_config.py:974", "expect": "def resolve_token"},
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{"anchor": "gitea_config.py:1015", "expect": "def keychain_auth"},
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{"anchor": "gitea_config.py:294", "expect": "def _validate_identity_auth"},
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{"anchor": "mcp_daemon_guard.py:440", "expect": "def assert_keychain_access_allowed"},
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{"anchor": "gitea_mcp_server.py:19258", "expect": "def gitea_list_profiles"},
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{"anchor": "gitea_mcp_server.py:19309", "expect": "gitea_config.resolve_token(p)"},
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{"anchor": "gitea_mcp_server.py:19552", "expect": "def gitea_audit_config"},
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{"anchor": "gitea_mcp_server.py:19574", "expect": "service_summaries(config)"},
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{"anchor": "mcp_daemon_guard.py:519", "expect": "def assert_keychain_access_allowed"},
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{"anchor": "gitea_mcp_server.py:19261", "expect": "def gitea_list_profiles"},
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{"anchor": "gitea_mcp_server.py:19312", "expect": "gitea_config.resolve_token(p)"},
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{"anchor": "gitea_mcp_server.py:19555", "expect": "def gitea_audit_config"},
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{"anchor": "gitea_mcp_server.py:19577", "expect": "service_summaries(config)"},
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{"anchor": "gitea_config.py:704", "expect": "def resolve_service"},
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{"anchor": "gitea_config.py:837", "expect": "def service_summaries"},
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{"anchor": "gitea_config.py:851", "expect": "_keychain_token(auth.get(\"id\"))"},
|
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{"anchor": "gitea_mcp_server.py:17707", "expect": "\"jenkins-mcp\""},
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{"anchor": "gitea_mcp_server.py:17713", "expect": "external-mcp"},
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{"anchor": "gitea_mcp_server.py:17734", "expect": "\"glitchtip-mcp\""},
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{"anchor": "gitea_mcp_server.py:17739", "expect": "external-mcp"},
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{"anchor": "gitea_mcp_server.py:17710", "expect": "\"jenkins-mcp\""},
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{"anchor": "gitea_mcp_server.py:17716", "expect": "external-mcp"},
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{"anchor": "gitea_mcp_server.py:17737", "expect": "\"glitchtip-mcp\""},
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{"anchor": "gitea_mcp_server.py:17742", "expect": "external-mcp"},
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{"anchor": "mcp_discoverability.py:9", "expect": "EXPECTED_JENKINS_TOOLS"},
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{"anchor": "mcp_discoverability.py:17", "expect": "EXPECTED_GLITCHTIP_TOOLS"},
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@@ -59,13 +59,13 @@
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{"anchor": "master_parity_gate.py:168", "expect": "def capture_startup_parity"},
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{"anchor": "master_parity_gate.py:255", "expect": "mutation_safe"},
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{"anchor": "gitea_mcp_server.py:19102", "expect": "def gitea_assess_master_parity"},
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{"anchor": "gitea_mcp_server.py:19105", "expect": "def gitea_assess_master_parity"},
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{"anchor": "gitea_mcp_server.py:190", "expect": "ACTIVE_WORKTREE_ENV"},
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{"anchor": "gitea_mcp_server.py:191", "expect": "AUTHOR_WORKTREE_ENV"},
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{"anchor": "gitea_mcp_server.py:2348", "expect": "/tmp/gitea_issue_lock.json"},
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{"anchor": "gitea_mcp_server.py:10894", "expect": "def gitea_bootstrap_author_issue_worktree"},
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{"anchor": "mcp_server.py:10", "expect": "/tmp/mcp_server_stderr.log"},
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{"anchor": "gitea_mcp_server.py:193", "expect": "ACTIVE_WORKTREE_ENV"},
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{"anchor": "gitea_mcp_server.py:194", "expect": "AUTHOR_WORKTREE_ENV"},
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{"anchor": "gitea_mcp_server.py:2351", "expect": "/tmp/gitea_issue_lock.json"},
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{"anchor": "gitea_mcp_server.py:10897", "expect": "def gitea_bootstrap_author_issue_worktree"},
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{"anchor": "mcp_server.py:13", "expect": "/tmp/mcp_server_stderr.log"},
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{"anchor": "issue_lock_store.py:26", "expect": "DEFAULT_LOCK_DIR"},
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{"anchor": "issue_lock_store.py:83", "expect": "def session_pointer_path"},
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@@ -75,6 +75,6 @@
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{"anchor": "control_plane_db.py:380", "expect": "mode=0o700"},
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{"anchor": "control_plane_db.py:386", "expect": "sqlite3.connect"},
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{"anchor": "control_plane_db.py:1145", "expect": "os.getpid()"},
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{"anchor": "gitea_mcp_server.py:12801", "expect": "owner_pid_alive"}
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{"anchor": "gitea_mcp_server.py:12804", "expect": "owner_pid_alive"}
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]
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}
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@@ -27,7 +27,7 @@ document cites an anchor the fixture does not cover.
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This guard exists because #930 did not have one. Its inventory was generated at
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`7bf4f125`; by `aad5c8b4` its `gitea_mcp_server.py` anchors had drifted — the transport
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bind it cited at line 23750 now lives at `gitea_mcp_server.py:24721`, and its
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bind it cited at line 23750 now lives at `gitea_mcp_server.py:24728`, and its
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client-managed provenance anchor at 14588 now lands in an unrelated function. Nothing
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failed, because nothing checked. Anchors into a ~24,700-line module rot silently, and a
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security document that cannot prove its own citations is worse than none, because it is
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@@ -75,15 +75,15 @@ authenticate the *caller*, not the *intent*.
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| ID | Boundary | Protects | Crossing requires today | Crossing must require remotely |
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| -- | -------- | -------- | ----------------------- | ------------------------------ |
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| B1 | LLM client ↔ MCP server session | A1, A3, A10 — that a mutating session was established through the sanctioned client path | A literal `stdio` bind (`gitea_mcp_server.py:24721`) inside a closed allowlist (`mcp_daemon_guard.py:45`, `mcp_daemon_guard.py:174`); client-managed provenance (`gitea_mcp_server.py:15412`) or a refusal (`gitea_mcp_server.py:15450`); production transport before recovery-authorization mint (`irrecoverable_provenance.py:497`, consumed at `gitea_mcp_server.py:9129` and `gitea_mcp_server.py:9378`) | An authenticated handshake issuing a server-side session identity bound to a principal, with the transport recorded in provenance. The physical proof (a pipe) must become a cryptographic one. |
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| B1 | LLM client ↔ MCP server session | A1, A3, A10 — that a mutating session was established through the sanctioned client path | A single configured bind (`gitea_mcp_server.py:24728`) validated against one closed allowlist (`mcp_daemon_guard.py:49`, `mcp_daemon_guard.py:178`) — since #931 the identifier comes from deployment configuration and defaults to the local transport, so the boundary no longer rests on a literal, but it still rests on the *bind* rather than on an authenticated caller; client-managed provenance (`gitea_mcp_server.py:15415`) or a refusal (`gitea_mcp_server.py:15453`); production transport before recovery-authorization mint (`irrecoverable_provenance.py:497`, consumed at `gitea_mcp_server.py:9132` and `gitea_mcp_server.py:9381`) | An authenticated handshake issuing a server-side session identity bound to a principal, with the transport recorded in provenance. The physical proof (a pipe) must become a cryptographic one. |
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| B2 | Role ↔ role | A9 — that author, reviewer, merger, and reconciler are distinct authorities | **The process boundary only.** The role is a property of the process, read once from `GITEA_MCP_PROFILE` (`gitea_config.py:54`). A caller gets author permissions by connecting to the author process. Review and merge are the operations singled out for extra care (`gitea_config.py:97`) | A per-request principal, so the role follows from the credential presented and cannot be selected by reaching a different endpoint. |
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| B3 | MCP server ↔ credential store | A3, A8 — that only sanctioned code turns a profile into a token | `_keychain_token` shelling out to the login keychain (`gitea_config.py:956`), dispatched by `resolve_token` (`gitea_config.py:974`) with the reference type built at `gitea_config.py:1015`, gated by `assert_keychain_access_allowed` (`mcp_daemon_guard.py:440`). Inline secrets are rejected at config load (`gitea_config.py:294`) | A credential provider keyed by the *request* principal, returning only that principal's credential, with the source recorded and the value never returned. |
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| B3 | MCP server ↔ credential store | A3, A8 — that only sanctioned code turns a profile into a token | `_keychain_token` shelling out to the login keychain (`gitea_config.py:956`), dispatched by `resolve_token` (`gitea_config.py:974`) with the reference type built at `gitea_config.py:1015`, gated by `assert_keychain_access_allowed` (`mcp_daemon_guard.py:519`). Inline secrets are rejected at config load (`gitea_config.py:294`) | A credential provider keyed by the *request* principal, returning only that principal's credential, with the source recorded and the value never returned. |
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| B4 | MCP server ↔ Gitea | A1, A2 — that only authorized calls reach the forge | A bearer token over TLS. Server-side, nothing distinguishes one role's token from another beyond the account it belongs to | Unchanged at the forge; the endpoint in front of it must refuse unauthenticated and plaintext connections before tool dispatch. |
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| B5 | MCP server ↔ caller's filesystem | A7 — that a tool acts on the *caller's* disk or refuses | Nothing. The server's disk *is* the caller's disk. Worktree bootstrap writes directly (`gitea_mcp_server.py:10894`); the active workspace is process-global (`gitea_mcp_server.py:190`, `gitea_mcp_server.py:191`) | An explicit per-tool classification, enforced at dispatch, refusing filesystem tools over a transport that cannot reach the caller's disk. A green verdict about the wrong disk is the failure to prevent. |
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| B6 | MCP server ↔ coordination state | A6, A9 — mutual exclusion | Local files and a local SQLite database, with liveness judged from the local process table (`issue_lock_store.py:98`), keyed on paths under one user's home (`issue_lock_store.py:26`, `mcp_session_state.py:27`, `control_plane_db.py:47`) and on `os.getpid()` (`control_plane_db.py:1145`, `gitea_mcp_server.py:12801`). A legacy global slot still exists at `gitea_mcp_server.py:2348`, and the session-pointer file is named per PID (`issue_lock_store.py:83`) | One authority per ownership question, with liveness from session identity and expiry, and atomic acquire, renew, and release across hosts. |
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| B5 | MCP server ↔ caller's filesystem | A7 — that a tool acts on the *caller's* disk or refuses | Nothing. The server's disk *is* the caller's disk. Worktree bootstrap writes directly (`gitea_mcp_server.py:10897`); the active workspace is process-global (`gitea_mcp_server.py:193`, `gitea_mcp_server.py:194`) | An explicit per-tool classification, enforced at dispatch, refusing filesystem tools over a transport that cannot reach the caller's disk. A green verdict about the wrong disk is the failure to prevent. |
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| B6 | MCP server ↔ coordination state | A6, A9 — mutual exclusion | Local files and a local SQLite database, with liveness judged from the local process table (`issue_lock_store.py:98`), keyed on paths under one user's home (`issue_lock_store.py:26`, `mcp_session_state.py:27`, `control_plane_db.py:47`) and on `os.getpid()` (`control_plane_db.py:1145`, `gitea_mcp_server.py:12804`). A legacy global slot still exists at `gitea_mcp_server.py:2351`, and the session-pointer file is named per PID (`issue_lock_store.py:83`) | One authority per ownership question, with liveness from session identity and expiry, and atomic acquire, renew, and release across hosts. |
|
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| B7 | Gitea integration ↔ unrelated integrations | A4, A5 — that a Gitea compromise is not a CI and observability compromise | **Nothing.** See §5. The Gitea server reads Jenkins and GlitchTip secrets (`gitea_config.py:851`, reached from `gitea_config.py:837`) and holds the Sentry token (`sentry_incident_bridge.py:190`) | A hard process boundary. This is the boundary #956 exists to create. |
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| B8 | Tenant ↔ tenant (`prgs` / `mdcps` / `local-lab`) | A2 — that one organization's compromise is not another's | Convention. One configuration declares all three contexts; `resolve_service` fails closed on a *disabled* context (`gitea_config.py:704`) but the credentials of enabled ones remain reachable in-process. A per-profile repository scope exists (`gitea_config.py:499`) | Separate deployments, or at minimum per-tenant credential scopes with no process able to resolve both. |
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| B9 | Deployed code ↔ merged policy | A1, A10 — that the running server enforces the rules that were actually merged | Comparing this process's startup commit against this disk (`master_parity_gate.py:168`), conjoined into a single verdict (`master_parity_gate.py:255`) published by `gitea_mcp_server.py:19102` | Freshness defined against the deployed build identity, with an explicit fail-closed verdict when undeterminable. |
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| B9 | Deployed code ↔ merged policy | A1, A10 — that the running server enforces the rules that were actually merged | Comparing this process's startup commit against this disk (`master_parity_gate.py:168`), conjoined into a single verdict (`master_parity_gate.py:255`) published by `gitea_mcp_server.py:19105` | Freshness defined against the deployed build identity, with an explicit fail-closed verdict when undeterminable. |
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### What no boundary constrains
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@@ -128,10 +128,10 @@ Two flows deserve attention because neither is obvious from the code:
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1. **The keychain flow fans out.** B3 is drawn once but resolves credentials for *every*
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configured profile and service, not only the active one. `gitea_list_profiles`
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(`gitea_mcp_server.py:19258`) reports each profile's credential status by calling
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`resolve_token` on it (`gitea_mcp_server.py:19309`), and `gitea_audit_config`
|
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(`gitea_mcp_server.py:19552`) reports service credential status through
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`service_summaries` (`gitea_mcp_server.py:19574`).
|
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(`gitea_mcp_server.py:19261`) reports each profile's credential status by calling
|
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`resolve_token` on it (`gitea_mcp_server.py:19312`), and `gitea_audit_config`
|
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(`gitea_mcp_server.py:19555`) reports service credential status through
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`service_summaries` (`gitea_mcp_server.py:19577`).
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2. **The return path is a flow too.** Content read from Gitea travels back into the model
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and is treated as instruction. This is the ADV2 edge, and it is the only edge in the
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diagram with no authentication on it, because it is not a request.
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@@ -156,7 +156,7 @@ an attacker holding a token calls the API, not our tools.
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| CR10 | MDCPS GlitchTip read credential | macOS keychain, read from the Gitea server process (`gitea_config.py:851`) | B7 | Read error events and their payloads (A5). Enabled today. |
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| CR11 | `SENTRY_AUTH_TOKEN` | Process environment, read in-process (`sentry_incident_bridge.py:36`, `sentry_incident_bridge.py:190`), sent as a bearer header (`sentry_incident_bridge.py:289`) | B7 | Read and reconcile Sentry issues (A5). Not a keychain credential — an env var, so it is inherited by anything the process spawns. |
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| CR12 | `SENTRY_DSN` | Process environment (`sentry_observability.py:55`) | B7 | Write events into the observability project. Low read value, real forgery value: an attacker can inject fabricated events into the record (A10). |
|
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| CR13 | macOS login keychain access | The operator's login session; gated by `assert_keychain_access_allowed` (`mcp_daemon_guard.py:440`) | B3, ADV5 | **Every other credential in this table except CR11 and CR12.** This is the aggregation point. |
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| CR13 | macOS login keychain access | The operator's login session; gated by `assert_keychain_access_allowed` (`mcp_daemon_guard.py:519`) | B3, ADV5 | **Every other credential in this table except CR11 and CR12.** This is the aggregation point. |
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| CR14 | Coordination-store access (no secret) | Filesystem permissions — `control_plane_db.py:47`, created `0o700` (`control_plane_db.py:380`), opened with a local file lock (`control_plane_db.py:386`) | B6, ADV5 | Full read/write of locks, leases, and decision records (A6). **There is no credential here at all** — anything running as the operator can rewrite ownership. |
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### Findings
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@@ -176,16 +176,16 @@ the credential, and an attacker holding the token does not call our tools.
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**Finding 3 — Any one role process can resolve every other role's credential.** This is not
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inferred; it is demonstrated by tool output. `gitea_list_profiles`
|
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(`gitea_mcp_server.py:19258`) called from the **author** session reports
|
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(`gitea_mcp_server.py:19261`) called from the **author** session reports
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`identity_status: "credentials present"` for `prgs-merger`, `prgs-reviewer`,
|
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`prgs-reconciler`, and every `mdcps` profile, because it calls `resolve_token` on each one
|
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(`gitea_mcp_server.py:19309`). The author process does not merely *have access to* the
|
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(`gitea_mcp_server.py:19312`). The author process does not merely *have access to* the
|
||||
merger's credential — it reads it to answer a status query. B2 is not a credential boundary
|
||||
in either direction.
|
||||
|
||||
**Finding 4 — The Gitea server reads CI and observability secrets.** `gitea_audit_config`
|
||||
(`gitea_mcp_server.py:19552`) reports `MDCPS Jenkins: enabled, read-only, authenticated`.
|
||||
That word `authenticated` is produced by `service_summaries` (`gitea_mcp_server.py:19574`,
|
||||
(`gitea_mcp_server.py:19555`) reports `MDCPS Jenkins: enabled, read-only, authenticated`.
|
||||
That word `authenticated` is produced by `service_summaries` (`gitea_mcp_server.py:19577`,
|
||||
defined at `gitea_config.py:837`), whose default check calls `_keychain_token` on the
|
||||
service's own keychain reference (`gitea_config.py:851`). Producing that one line requires
|
||||
the Gitea MCP server to read the Jenkins secret and the GlitchTip secret out of the
|
||||
@@ -193,8 +193,8 @@ keychain. B7 does not exist.
|
||||
|
||||
**Finding 5 — Jenkins and GlitchTip are already decomposed; the reach is residual.** Their
|
||||
tools live in separately registered servers, marked `external-mcp`
|
||||
(`gitea_mcp_server.py:17707`, `gitea_mcp_server.py:17713`, `gitea_mcp_server.py:17734`,
|
||||
`gitea_mcp_server.py:17739`) with their own expected tool sets (`mcp_discoverability.py:9`,
|
||||
(`gitea_mcp_server.py:17710`, `gitea_mcp_server.py:17716`, `gitea_mcp_server.py:17737`,
|
||||
`gitea_mcp_server.py:17742`) with their own expected tool sets (`mcp_discoverability.py:9`,
|
||||
`mcp_discoverability.py:17`). The correct decomposition was already chosen. What remains is
|
||||
a leak across it: the credential *references* still live in the Gitea configuration and are
|
||||
still resolved by the Gitea process. #75 bundled these services into one control-plane
|
||||
@@ -205,8 +205,8 @@ GlitchTip, the Sentry bridge runs *inside* the Gitea server, resolving its token
|
||||
process environment (`sentry_incident_bridge.py:190`) and sending it as a bearer header
|
||||
(`sentry_incident_bridge.py:289`). Being an environment variable rather than a keychain item
|
||||
makes it strictly worse: it needs no keychain prompt and is inherited by every subprocess the
|
||||
server spawns — including the `ps` invocations at `gitea_mcp_server.py:21462` and
|
||||
`gitea_mcp_server.py:21506`, reached from `gitea_mcp_server.py:21442`.
|
||||
server spawns — including the `ps` invocations at `gitea_mcp_server.py:21465` and
|
||||
`gitea_mcp_server.py:21509`, reached from `gitea_mcp_server.py:21445`.
|
||||
|
||||
**Finding 7 — The highest-value coordination asset has the weakest gate.** A6 is protected
|
||||
by filesystem permissions alone (CR14). Corrupting a lease requires no Gitea credential,
|
||||
@@ -215,13 +215,15 @@ assumes. Every other asset costs an attacker a credential; this one costs nothin
|
||||
local access, which is exactly ADV5's position.
|
||||
|
||||
**Finding 8 — Provenance authenticates the launch, not the caller.** `server_provenance` is
|
||||
reported as exactly `client_managed` or `manual_launch` (`gitea_mcp_server.py:19001`),
|
||||
derived from environment inspection (`gitea_mcp_server.py:15412`) with the recognized-key
|
||||
reported as exactly `client_managed` or `manual_launch` (`gitea_mcp_server.py:19004`),
|
||||
derived from environment inspection (`gitea_mcp_server.py:15415`) with the recognized-key
|
||||
allowlist at `gitea_config.py:1172` and the generator that emits the marker at
|
||||
`gitea_config.py:1233`. Every one of those facts is fixed at process start. A client that is
|
||||
trustworthy at launch and compromised a minute later remains `client_managed` for the life
|
||||
of the process, and the stdio contract that underwrites it is stated as a property of the
|
||||
server itself (`mcp_server.py:4`).
|
||||
of the process, and the transport contract that underwrites it is stated as a property of
|
||||
the server itself (`mcp_server.py:4`). Since #931 that contract names the configured
|
||||
transport rather than asserting stdio, but it is still fixed once, at bind, for the life of
|
||||
the process.
|
||||
|
||||
## 6. Decomposition ruling
|
||||
|
||||
@@ -253,7 +255,7 @@ holds the token and calls the API instead of the tool.
|
||||
|
||||
**D3 — Credential resolution is scoped to the request principal.** A session must resolve its
|
||||
own credential and must have no path to any other principal's. The resolve-every-profile
|
||||
behavior behind `gitea_mcp_server.py:19309` and `gitea_mcp_server.py:19574` must report
|
||||
behavior behind `gitea_mcp_server.py:19312` and `gitea_mcp_server.py:19577` must report
|
||||
configured-or-not from configuration alone, without resolving the secret.
|
||||
|
||||
*Rationale.* Finding 3. An audit surface that proves a credential exists by fetching it is a
|
||||
@@ -330,11 +332,11 @@ The client is attached to the local fleet over stdio.
|
||||
|
||||
| Boundary | What ADV1 reaches | Stopped by |
|
||||
| -------- | ----------------- | ---------- |
|
||||
| B1 | Everything the fleet serves. The client *is* the sanctioned launcher: it satisfies the client-managed check (`gitea_mcp_server.py:15412`) by construction, and provenance is never re-verified after launch (Finding 8). | Nothing. The guard authenticates the launch, not the caller. |
|
||||
| B1 | Everything the fleet serves. The client *is* the sanctioned launcher: it satisfies the client-managed check (`gitea_mcp_server.py:15415`) by construction, and provenance is never re-verified after launch (Finding 8). | Nothing. The guard authenticates the launch, not the caller. |
|
||||
| B2 | All five roles — it is attached to all five namespaces. It can author a PR, approve it from the reviewer namespace, and merge it from the merger namespace. | Only the in-process self-review check, which compares `jcwalker3` (author) against `sysadmin` (reviewer) and **passes**, because Finding 1 made them different accounts while leaving reviewer and merger identical. A9 falls in one sequence of legitimate calls. |
|
||||
| B3 | Every credential in CR1–CR10 via CR13, with no additional prompt — the daemon is already sanctioned, so `assert_keychain_access_allowed` (`mcp_daemon_guard.py:440`) returns immediately. | Nothing. |
|
||||
| B3 | Every credential in CR1–CR10 via CR13, with no additional prompt — the daemon is already sanctioned, so `assert_keychain_access_allowed` (`mcp_daemon_guard.py:519`) returns immediately. | Nothing. |
|
||||
| B4 | A1 and A2 in full. | Branch protection at the forge, to the extent configured. |
|
||||
| B5 | The operator's checkout and every worktree, through the author tools (`gitea_mcp_server.py:10894`), plus the shared stderr path at `mcp_server.py:10`. | Nothing; the server's disk is the target disk. |
|
||||
| B5 | The operator's checkout and every worktree, through the author tools (`gitea_mcp_server.py:10897`), plus the shared stderr path at `mcp_server.py:13`. | Nothing; the server's disk is the target disk. |
|
||||
| B6 | All coordination state — no credential required (CR14). It can forge lease ownership and clear decision locks. | Filesystem permissions, which it already satisfies. |
|
||||
| B7 | Jenkins (A4) and GlitchTip (A5) secrets via Finding 4, and CR11/CR12 from its own environment. | Nothing. |
|
||||
| B8 | Both tenants. | Nothing in-process; only the disabled-context check (`gitea_config.py:704`), which does not apply to enabled contexts. |
|
||||
|
||||
Reference in New Issue
Block a user