---
phase: 04-security
plan: 03
subsystem: auth
tags: [ed25519, sse-signing, payload-integrity, server-sent-events]

# Dependency graph
requires:
  - phase: 04-security
    provides: "Ed25519SigningService interface and implementation from Plan 01"
  - phase: 03-agent-registry
    provides: "SseConnectionManager, AgentCommand, SSE event delivery"
provides:
  - "SsePayloadSigner component for Ed25519 signing of SSE command payloads"
  - "All SSE command events (config-update, deep-trace, replay) carry verifiable signature field"
affects: []

# Tech tracking
tech-stack:
  added: []
  patterns: [sign-then-serialize for SSE payloads, JsonNode passthrough for correct SseEmitter serialization]

key-files:
  created:
    - cameleer-server-app/src/main/java/com/cameleer/server/app/agent/SsePayloadSigner.java
    - cameleer-server-app/src/test/java/com/cameleer/server/app/agent/SsePayloadSignerTest.java
    - cameleer-server-app/src/test/java/com/cameleer/server/app/security/SseSigningIT.java
  modified:
    - cameleer-server-app/src/main/java/com/cameleer/server/app/agent/SseConnectionManager.java

key-decisions:
  - "Signed payload parsed to JsonNode before passing to SseEmitter to avoid double-quoting raw JSON strings"
  - "SseSigningIT uses bootstrap token + JWT auth (adapts to Plan 02 security layer introduced during parallel execution)"

patterns-established:
  - "Sign-then-serialize: signature computed over original payload string, then payload parsed and signature field added"
  - "Defensive null/blank handling in SsePayloadSigner returns payload unchanged with warning log"

requirements-completed: [SECU-04]

# Metrics
duration: 17min
completed: 2026-03-11
---

# Phase 4 Plan 03: SSE Payload Signing Summary

**Ed25519 signature injection into all SSE command events (config-update, deep-trace, replay) with end-to-end verification tests using JDK Signature API**

## Performance

- **Duration:** 17 min
- **Started:** 2026-03-11T19:12:25Z
- **Completed:** 2026-03-11T19:29:30Z
- **Tasks:** 1 (TDD: RED + GREEN)
- **Files modified:** 4

## Accomplishments
- SsePayloadSigner signs JSON payloads with Ed25519 and adds Base64-encoded signature field
- SseConnectionManager signs all command payloads before SSE delivery, parses to JsonNode for correct serialization
- 7 unit tests verify signature roundtrip, edge cases (null/empty/blank), and Base64 encoding
- 2 integration tests verify end-to-end: command sent with bootstrap+JWT auth, SSE event received with valid Ed25519 signature
- Ping keepalive events remain unsigned (they are SSE comments, not data events)

## Task Commits

Each task was committed atomically (TDD flow):

1. **Task 1 RED: Failing tests for SSE payload signing** - `b3b4e62` (test)
2. **Task 1 GREEN: Implement SSE payload signing** - `0215fd9` (feat)

_No REFACTOR commit needed -- implementation is clean and minimal._

## Files Created/Modified

- `cameleer-server-app/.../agent/SsePayloadSigner.java` - Component that signs JSON payloads with Ed25519 and adds signature field
- `cameleer-server-app/.../agent/SseConnectionManager.java` - Updated onCommandReady to sign payload before SSE delivery
- `cameleer-server-app/.../agent/SsePayloadSignerTest.java` - 7 unit tests for signing behavior and edge cases
- `cameleer-server-app/.../security/SseSigningIT.java` - 2 integration tests for end-to-end signature verification

## Decisions Made

- **JsonNode passthrough for SseEmitter:** The signed payload string is parsed to a Jackson JsonNode before passing to SseEmitter.event().data(). This avoids the double-quoting problem where a raw JSON string would be wrapped in additional quotes by Jackson's message converter.
- **Adapted to Plan 02 security layer:** SseSigningIT was updated to use bootstrap token for registration and JWT query param for SSE connection, since Plan 02 (Spring Security filter chain) was committed during parallel execution of this plan.

## Deviations from Plan

### Auto-fixed Issues

**1. [Rule 3 - Blocking] Updated SseSigningIT for Plan 02 security requirements**
- **Found during:** Task 1 GREEN phase (integration test execution)
- **Issue:** Plan 02 was committed in parallel, introducing real SecurityConfig that requires bootstrap token + JWT. The original test plan assumed TestSecurityConfig permit-all would be active.
- **Fix:** Updated SseSigningIT to register with bootstrap token, extract JWT from response, and use JWT query param for SSE connection.
- **Files modified:** SseSigningIT.java
- **Verification:** Both integration tests pass with full auth flow
- **Committed in:** 0215fd9 (GREEN phase commit)

---

**Total deviations:** 1 auto-fixed (1 blocking)
**Impact on plan:** Necessary adaptation to parallel plan execution. No scope creep.

## Pre-existing Failures (Out of Scope)

8 integration test failures pre-exist from Plan 02's security integration (not caused by this plan's changes):
- AgentSseControllerIT: 1 failure (unknownAgent expected 404, gets 403)
- AgentCommandControllerIT: 2 failures (unauthenticated requests get 403 instead of 404)
- JwtRefreshIT: 5 failures (all tests, likely missing bootstrap token in setup)

Logged to `deferred-items.md` in this phase directory.

## Issues Encountered

None specific to this plan's scope.

## User Setup Required

None - no external service configuration required.

## Next Phase Readiness

- All SSE command events now carry verifiable Ed25519 signatures
- Security phase implementation is complete (Plans 01, 02, 03)
- Pre-existing test failures from Plan 02 need resolution (documented in deferred-items.md)

## Self-Check: PASSED

- All 4 created/modified files verified present on disk
- Both commits (b3b4e62, 0215fd9) verified in git log
- Unit tests: 7 pass, Integration tests: 2 pass

---
*Phase: 04-security*
*Completed: 2026-03-11*
