enclave-token-map

name	enclave-token-map
description	Per-session tokenization engine with same-origin enforcement for the Latch Enclave. Replaces sensitive values with opaque tokens in proxy responses, and only resolves them when sent back to the originating service. Use when working on data tier enforcement, response redaction, or the token same-origin policy.

Token Map

The TokenMap class lives at src/main/services/proxy/token-map.ts and implements per-session value tokenization with same-origin enforcement.

Core Concept: Token Same-Origin Policy

Sensitive values from service responses are replaced with opaque tokens (tok_a3f8b2c1). These tokens carry origin metadata (service, tier, endpoint) and can ONLY be resolved back to their real value when the destination matches the origin service. This prevents cross-service data exfiltration.

Key API

• tokenize(value, origin) — Creates a token for a sensitive value. Returns existing token if same value+service already tokenized.
• resolve(tokenId, destService) — Returns the real value if destService matches origin, null otherwise.
• tokenizeInString(text, value, origin) — Replaces all occurrences of a value in a string with its token.
• detokenizeString(text, destService) — Resolves all tok_* patterns in text for the given destination service.
• list() — Returns all active TokenEntry objects for audit.
• clear() — Destroys all tokens (called on session end).

Token Format

Tokens are tok_ followed by 8 hex characters: tok_[a-f0-9]{8}

Phase 2: Automatic Token Lifecycle

In Phase 2, tokens are created and resolved automatically by the proxy pipeline:

• Ingress (response scanning): The IngressFilter scans HTTP and decrypted HTTPS response bodies for sensitive patterns (defined by each service's dataTier.redaction.patterns). Matched values are tokenized via tokenizeInString(), which automatically creates tokens with same-origin metadata (service, tier, endpoint). The agent sees tok_* tokens instead of real values.

• Egress (request de-tokenization): Both the HTTP handler (_handleRequest) and the HTTPS MITM handler (_handleInterceptedRequest) call detokenizeString() on request bodies before forwarding upstream. Tokens are only resolved if the destination service matches the token's origin — cross-service exfiltration is blocked by the same-origin check.

This means tokens flow through the system without any manual intervention: created on ingress, resolved on egress, enforced by origin throughout.

Architecture Notes

• Each TokenMap instance is per-session — created when a session starts, cleared when it ends
• Deduplication: same value+service pair always returns the same token
• Used by LatchProxy for response body processing and request body de-tokenization
• Used by IngressFilter for automatic tokenization during response scanning
• TokenEntry includes: id, value, origin (service, tier, endpoint), validDestinations, createdAt

Testing

Tests: src/main/services/proxy/token-map.test.ts Run: npx vitest run src/main/services/proxy/token-map.test.ts