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Chris Lu 8fad85aed7 feat(s3): support WEED_S3_SSE_KEY env var for SSE-S3 KEK (#8904)
* feat(s3): support WEED_S3_SSE_KEY env var for SSE-S3 KEK

Add support for providing the SSE-S3 Key Encryption Key (KEK) via the
WEED_S3_SSE_KEY environment variable (hex-encoded 256-bit key). This
avoids storing the master key in plaintext on the filer at /etc/s3/sse_kek.

Key source priority:
1. WEED_S3_SSE_KEY environment variable (recommended)
2. Existing filer KEK at /etc/s3/sse_kek (backward compatible)
3. Auto-generate and save to filer (deprecated for new deployments)

Existing deployments with a filer-stored KEK continue to work unchanged.
A deprecation warning is logged when auto-generating a new filer KEK.

* refactor(s3): derive KEK from any string via HKDF instead of requiring hex

Accept any secret string in WEED_S3_SSE_KEY and derive a 256-bit key
using HKDF-SHA256 instead of requiring a hex-encoded key. This is
simpler for users — no need to generate hex, just set a passphrase.

* feat(s3): add WEED_S3_SSE_KEK and WEED_S3_SSE_KEY env vars for KEK

Two env vars for providing the SSE-S3 Key Encryption Key:

- WEED_S3_SSE_KEK: hex-encoded, same format as /etc/s3/sse_kek.
  If the filer file also exists, they must match.
- WEED_S3_SSE_KEY: any string, 256-bit key derived via HKDF-SHA256.
  Refuses to start if /etc/s3/sse_kek exists (must delete first).

Only one may be set. Existing filer-stored KEKs continue to work.
Auto-generating and storing new KEKs on filer is deprecated.

* fix(s3): stop auto-generating KEK, fail only when SSE-S3 is used

Instead of auto-generating a KEK and storing it on the filer when no
key source is configured, simply leave SSE-S3 disabled. Encrypt and
decrypt operations return a clear error directing the user to set
WEED_S3_SSE_KEK or WEED_S3_SSE_KEY.

* refactor(s3): move SSE-S3 KEK config to security.toml

Move KEK configuration from standalone env vars to security.toml's new
[sse_s3] section, following the same pattern as JWT keys and TLS certs.

  [sse_s3]
  kek = ""   # hex-encoded 256-bit key (same format as /etc/s3/sse_kek)
  key = ""   # any string, HKDF-derived

Viper's WEED_ prefix auto-mapping provides env var support:
WEED_SSE_S3_KEK and WEED_SSE_S3_KEY.

All existing behavior is preserved: filer KEK fallback, mismatch
detection, and HKDF derivation.

* refactor(s3): rename SSE-S3 config keys to s3.sse.kek / s3.sse.key

Use [s3.sse] section in security.toml, matching the existing naming
convention (e.g. [s3.*]). Env vars: WEED_S3_SSE_KEK, WEED_S3_SSE_KEY.

* fix(s3): address code review findings for SSE-S3 KEK

- Don't hold mutex during filer retry loop (up to 20s of sleep).
  Lock only to write filerClient and superKey.
- Remove dead generateAndSaveSuperKeyToFiler and unused constants.
- Return error from deriveKeyFromSecret instead of ignoring it.
- Fix outdated doc comment on InitializeWithFiler.
- Use t.Setenv in tests instead of manual os.Setenv/Unsetenv.

* fix(s3): don't block startup on filer errors when KEK is configured

- When s3.sse.kek is set, a temporarily unreachable filer no longer
  prevents startup. The filer consistency check becomes best-effort
  with a warning.
- Same treatment for s3.sse.key: filer unreachable logs a warning
  instead of failing.
- Rewrite error messages to suggest migration instead of file deletion,
  avoiding the risk of orphaning encrypted data.

Finding 3 (restore auto-generation) intentionally skipped — auto-gen
was removed by design to avoid storing plaintext KEK on filer.

* fix(test): set WEED_S3_SSE_KEY in SSE integration test server startup

SSE-S3 no longer auto-generates a KEK, so integration tests must
provide one. Set WEED_S3_SSE_KEY=test-sse-s3-key in all weed mini
invocations in the test Makefile.
2026-04-03 13:01:21 -07:00
..
2026-02-20 18:42:00 -08:00
2025-10-13 18:05:17 -07:00
2025-10-13 18:05:17 -07:00

S3 Server-Side Encryption (SSE) Integration Tests

This directory contains comprehensive integration tests for SeaweedFS S3 API Server-Side Encryption functionality. These tests validate the complete end-to-end encryption/decryption pipeline from S3 API requests through filer metadata storage.

Overview

The SSE integration tests cover three main encryption methods:

  • SSE-C (Customer-Provided Keys): Client provides encryption keys via request headers
  • SSE-KMS (Key Management Service): Server manages encryption keys through a KMS provider
  • SSE-S3 (Server-Managed Keys): Server automatically manages encryption keys

🆕 Real KMS Integration

The tests now include real KMS integration with OpenBao, providing:

  • Actual encryption/decryption operations (not mock keys)
  • Multiple KMS keys for different security levels
  • Per-bucket KMS configuration testing
  • Performance benchmarking with real KMS operations

See README_KMS.md for detailed KMS integration documentation.

Why Integration Tests Matter

These integration tests were created to address a critical gap in test coverage that previously existed. While the SeaweedFS codebase had comprehensive unit tests for SSE components, it lacked integration tests that validated the complete request flow:

Client Request → S3 API → Filer Storage → Metadata Persistence → Retrieval → Decryption

The Bug These Tests Would Have Caught

A critical bug was discovered where:

  • S3 API correctly encrypted data and sent metadata headers to the filer
  • Filer did not process SSE metadata headers, losing all encryption metadata
  • Objects could be encrypted but never decrypted (metadata was lost)

Unit tests passed because they tested components in isolation, but the integration was broken. These integration tests specifically validate that:

  1. Encryption metadata is correctly sent to the filer
  2. Filer properly processes and stores the metadata
  3. Objects can be successfully retrieved and decrypted
  4. Copy operations preserve encryption metadata
  5. Multipart uploads maintain encryption consistency

Test Structure

Core Integration Tests

Basic Functionality

  • TestSSECIntegrationBasic - Basic SSE-C PUT/GET cycle
  • TestSSEKMSIntegrationBasic - Basic SSE-KMS PUT/GET cycle

Data Size Validation

  • TestSSECIntegrationVariousDataSizes - SSE-C with various data sizes (0B to 1MB)
  • TestSSEKMSIntegrationVariousDataSizes - SSE-KMS with various data sizes

Object Copy Operations

  • TestSSECObjectCopyIntegration - SSE-C object copying (key rotation, encryption changes)
  • TestSSEKMSObjectCopyIntegration - SSE-KMS object copying

Multipart Uploads

  • TestSSEMultipartUploadIntegration - SSE multipart uploads for large objects

Error Conditions

  • TestSSEErrorConditions - Invalid keys, malformed requests, error handling

Performance Tests

  • BenchmarkSSECThroughput - SSE-C performance benchmarking
  • BenchmarkSSEKMSThroughput - SSE-KMS performance benchmarking

Running Tests

Prerequisites

  1. Build SeaweedFS: Ensure the weed binary is built and available in PATH

    cd /path/to/seaweedfs
    make
    
  2. Dependencies: Tests use AWS SDK Go v2 and testify - these are handled by Go modules

Quick Test

Run basic SSE integration tests:

make test-basic

Comprehensive Testing

Run all SSE integration tests:

make test

Specific Test Categories

make test-ssec      # SSE-C tests only
make test-ssekms    # SSE-KMS tests only  
make test-copy      # Copy operation tests
make test-multipart # Multipart upload tests
make test-errors    # Error condition tests

Performance Testing

make benchmark      # Performance benchmarks
make perf          # Various data size performance tests

KMS Integration Testing

make setup-openbao          # Set up OpenBao KMS
make test-with-kms          # Run all SSE tests with real KMS
make test-ssekms-integration # Run SSE-KMS with OpenBao only
make clean-kms             # Clean up KMS environment

Development Testing

make manual-start   # Start SeaweedFS for manual testing
# ... run manual tests ...
make manual-stop    # Stop and cleanup

Test Configuration

Default Configuration

The tests use these default settings:

  • S3 Endpoint: http://127.0.0.1:8333
  • Access Key: some_access_key1
  • Secret Key: some_secret_key1
  • Region: us-east-1
  • Bucket Prefix: test-sse-

Custom Configuration

Override defaults via environment variables:

S3_PORT=8444 FILER_PORT=8889 make test

Test Environment

Each test run:

  1. Starts a complete SeaweedFS cluster (master, volume, filer, s3)
  2. Configures KMS support for SSE-KMS tests
  3. Creates temporary buckets with unique names
  4. Runs tests with real HTTP requests
  5. Cleans up all test artifacts

Test Data Coverage

Data Sizes Tested

  • 0 bytes: Empty files (edge case)
  • 1 byte: Minimal data
  • 16 bytes: Single AES block
  • 31 bytes: Just under two blocks
  • 32 bytes: Exactly two blocks
  • 100 bytes: Small file
  • 1 KB: Small text file
  • 8 KB: Medium file
  • 64 KB: Large file
  • 1 MB: Very large file

Encryption Key Scenarios

  • SSE-C: Random 256-bit keys, key rotation, wrong keys
  • SSE-KMS: Various key IDs, encryption contexts, bucket keys
  • Copy Operations: Same key, different keys, encryption transitions

Critical Test Scenarios

Metadata Persistence Validation

The integration tests specifically validate scenarios that would catch metadata storage bugs:

// 1. Upload with SSE-C
client.PutObject(..., SSECustomerKey: key)  // ← Metadata sent to filer

// 2. Retrieve with SSE-C  
client.GetObject(..., SSECustomerKey: key)  // ← Metadata retrieved from filer

// 3. Verify decryption works
assert.Equal(originalData, decryptedData)    // ← Would fail if metadata lost

Content-Length Validation

Tests verify that Content-Length headers are correct, which would catch bugs related to IV handling:

assert.Equal(int64(originalSize), resp.ContentLength)  // ← Would catch IV-in-stream bugs

Debugging

View Logs

make debug-logs     # Show recent log entries
make debug-status   # Show process and port status

Manual Testing

make manual-start   # Start SeaweedFS
# Test with S3 clients, curl, etc.
make manual-stop    # Cleanup

Integration Test Benefits

These integration tests provide:

  1. End-to-End Validation: Complete request pipeline testing
  2. Metadata Persistence: Validates filer storage/retrieval of encryption metadata
  3. Real Network Communication: Uses actual HTTP requests and responses
  4. Production-Like Environment: Full SeaweedFS cluster with all components
  5. Regression Protection: Prevents critical integration bugs
  6. Performance Baselines: Benchmarking for performance monitoring

Continuous Integration

For CI/CD pipelines, use:

make ci-test        # Quick tests suitable for CI
make stress         # Stress testing for stability validation

Key Differences from Unit Tests

Aspect Unit Tests Integration Tests
Scope Individual functions Complete request pipeline
Dependencies Mocked/simulated Real SeaweedFS cluster
Network None Real HTTP requests
Storage In-memory Real filer database
Metadata Manual simulation Actual storage/retrieval
Speed Fast (milliseconds) Slower (seconds)
Coverage Component logic System integration

Conclusion

These integration tests ensure that SeaweedFS SSE functionality works correctly in production-like environments. They complement the existing unit tests by validating that all components work together properly, providing confidence that encryption/decryption operations will succeed for real users.

Most importantly, these tests would have immediately caught the critical filer metadata storage bug that was previously undetected, demonstrating the crucial importance of integration testing for distributed systems.