From 7b20d7da3cc7f734ac8ed9e69a8208ef25cd0668 Mon Sep 17 00:00:00 2001 From: Chris Lu Date: Fri, 2 Jan 2026 11:34:20 -0800 Subject: [PATCH] Delete SSE-C_IMPLEMENTATION.md --- SSE-C_IMPLEMENTATION.md | 169 ---------------------------------------- 1 file changed, 169 deletions(-) delete mode 100644 SSE-C_IMPLEMENTATION.md diff --git a/SSE-C_IMPLEMENTATION.md b/SSE-C_IMPLEMENTATION.md deleted file mode 100644 index 55da0aa70..000000000 --- a/SSE-C_IMPLEMENTATION.md +++ /dev/null @@ -1,169 +0,0 @@ -# Server-Side Encryption with Customer-Provided Keys (SSE-C) Implementation - -This document describes the implementation of SSE-C support in SeaweedFS, addressing the feature request from [GitHub Discussion #5361](https://github.com/seaweedfs/seaweedfs/discussions/5361). - -## Overview - -SSE-C allows clients to provide their own encryption keys for server-side encryption of objects stored in SeaweedFS. The server encrypts the data using the customer-provided AES-256 key but does not store the key itself - only an MD5 hash of the key for validation purposes. - -## Implementation Details - -### Architecture - -The SSE-C implementation follows a transparent encryption/decryption pattern: - -1. **Upload (PUT/POST)**: Data is encrypted with the customer key before being stored -2. **Download (GET/HEAD)**: Encrypted data is decrypted on-the-fly using the customer key -3. **Metadata Storage**: Only the encryption algorithm and key MD5 are stored as metadata - -### Key Components - -#### 1. Constants and Headers (`weed/s3api/s3_constants/header.go`) -- Added AWS-compatible SSE-C header constants -- Support for both regular and copy-source SSE-C headers - -#### 2. Core SSE-C Logic (`weed/s3api/s3_sse_c.go`) -- **SSECustomerKey**: Structure to hold customer encryption key and metadata -- **SSECEncryptedReader**: Streaming encryption with AES-256-CTR mode -- **SSECDecryptedReader**: Streaming decryption with IV extraction -- **validateAndParseSSECHeaders**: Shared validation logic (DRY principle) -- **ParseSSECHeaders**: Parse regular SSE-C headers -- **ParseSSECCopySourceHeaders**: Parse copy-source SSE-C headers -- Header validation and parsing functions -- Metadata extraction and response handling - -#### 3. Error Handling (`weed/s3api/s3err/s3api_errors.go`) -- New error codes for SSE-C validation failures -- AWS-compatible error messages and HTTP status codes - -#### 4. S3 API Integration -- **PUT Object Handler**: Encrypts data streams transparently -- **GET Object Handler**: Decrypts data streams transparently -- **HEAD Object Handler**: Validates keys and returns appropriate headers -- **Metadata Storage**: Integrates with existing `SaveAmzMetaData` function - -### Encryption Scheme - -- **Algorithm**: AES-256-CTR (Counter mode) -- **Key Size**: 256 bits (32 bytes) -- **IV Generation**: Random 16-byte IV per object -- **Storage Format**: `[IV][EncryptedData]` where IV is prepended to encrypted content - -### Metadata Storage - -SSE-C metadata is stored in the filer's extended attributes: -``` -x-amz-server-side-encryption-customer-algorithm: "AES256" -x-amz-server-side-encryption-customer-key-md5: "" -``` - -## API Compatibility - -### Required Headers for Encryption (PUT/POST) -``` -x-amz-server-side-encryption-customer-algorithm: AES256 -x-amz-server-side-encryption-customer-key: -x-amz-server-side-encryption-customer-key-md5: -``` - -### Required Headers for Decryption (GET/HEAD) -Same headers as encryption - the server validates the key MD5 matches. - -### Copy Operations -Support for copy-source SSE-C headers: -``` -x-amz-copy-source-server-side-encryption-customer-algorithm -x-amz-copy-source-server-side-encryption-customer-key -x-amz-copy-source-server-side-encryption-customer-key-md5 -``` - -## Error Handling - -The implementation provides AWS-compatible error responses: - -- **InvalidEncryptionAlgorithmError**: Non-AES256 algorithm specified -- **InvalidArgument**: Invalid key format, size, or MD5 mismatch -- **Missing customer key**: Object encrypted but no key provided -- **Unnecessary customer key**: Object not encrypted but key provided - -## Security Considerations - -1. **Key Management**: Customer keys are never stored - only MD5 hashes for validation -2. **IV Randomness**: Fresh random IV generated for each object -3. **Transparent Security**: Volume servers never see unencrypted data -4. **Key Validation**: Strict validation of key format, size, and MD5 - -## Testing - -Comprehensive test suite covers: -- Header validation and parsing (regular and copy-source) -- Encryption/decryption round-trip -- Error condition handling -- Metadata extraction -- Code reuse validation (DRY principle) -- AWS S3 compatibility - -Run tests with: -```bash -go test -v ./weed/s3api - -## Usage Example - -### Upload with SSE-C -```bash -# Generate a 256-bit key -KEY=$(openssl rand -base64 32) -KEY_MD5=$(echo -n "$KEY" | base64 -d | openssl dgst -md5 -binary | base64) - -# Upload object with SSE-C -curl -X PUT "http://localhost:8333/bucket/object" \ - -H "x-amz-server-side-encryption-customer-algorithm: AES256" \ - -H "x-amz-server-side-encryption-customer-key: $KEY" \ - -H "x-amz-server-side-encryption-customer-key-md5: $KEY_MD5" \ - --data-binary @file.txt -``` - -### Download with SSE-C -```bash -# Download object with SSE-C (same key required) -curl "http://localhost:8333/bucket/object" \ - -H "x-amz-server-side-encryption-customer-algorithm: AES256" \ - -H "x-amz-server-side-encryption-customer-key: $KEY" \ - -H "x-amz-server-side-encryption-customer-key-md5: $KEY_MD5" -``` - -## Integration Points - -### Existing SeaweedFS Features -- **Filer Metadata**: Extends existing metadata storage -- **Volume Servers**: No changes required - store encrypted data transparently -- **S3 API**: Integrates seamlessly with existing handlers -- **Versioning**: Compatible with object versioning -- **Multipart Upload**: Ready for multipart upload integration - -### Future Enhancements -- **SSE-S3**: Server-managed encryption keys -- **SSE-KMS**: External key management service integration -- **Performance Optimization**: Hardware acceleration for encryption -- **Compliance**: Enhanced audit logging for encrypted objects - -## File Changes Summary - -1. **`weed/s3api/s3_constants/header.go`** - Added SSE-C header constants -2. **`weed/s3api/s3_sse_c.go`** - Core SSE-C implementation (NEW) -3. **`weed/s3api/s3_sse_c_test.go`** - Comprehensive test suite (NEW) -4. **`weed/s3api/s3err/s3api_errors.go`** - Added SSE-C error codes -5. **`weed/s3api/s3api_object_handlers.go`** - GET/HEAD with SSE-C support -6. **`weed/s3api/s3api_object_handlers_put.go`** - PUT with SSE-C support -7. **`weed/server/filer_server_handlers_write_autochunk.go`** - Metadata storage - -## Compliance - -This implementation follows the [AWS S3 SSE-C specification](https://docs.aws.amazon.com/AmazonS3/latest/userguide/ServerSideEncryptionCustomerKeys.html) for maximum compatibility with existing S3 clients and tools. - -## Performance Impact - -- **Encryption Overhead**: Minimal CPU impact with efficient AES-CTR streaming -- **Memory Usage**: Constant memory usage via streaming encryption/decryption -- **Storage Overhead**: 16 bytes per object for IV storage -- **Network**: No additional network overhead