diff options
Diffstat (limited to 'weed/s3api/s3_sse_utils.go')
| -rw-r--r-- | weed/s3api/s3_sse_utils.go | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/weed/s3api/s3_sse_utils.go b/weed/s3api/s3_sse_utils.go index 848bc61ea..c902dc423 100644 --- a/weed/s3api/s3_sse_utils.go +++ b/weed/s3api/s3_sse_utils.go @@ -4,19 +4,22 @@ import "github.com/seaweedfs/seaweedfs/weed/glog" // calculateIVWithOffset calculates a unique IV by combining a base IV with an offset. // This ensures each chunk/part uses a unique IV, preventing CTR mode IV reuse vulnerabilities. +// Returns the adjusted IV and the number of bytes to skip from the decrypted stream. +// The skip is needed because CTR mode operates on 16-byte blocks, but the offset may not be block-aligned. // This function is shared between SSE-KMS and SSE-S3 implementations for consistency. -func calculateIVWithOffset(baseIV []byte, offset int64) []byte { +func calculateIVWithOffset(baseIV []byte, offset int64) ([]byte, int) { if len(baseIV) != 16 { glog.Errorf("Invalid base IV length: expected 16, got %d", len(baseIV)) - return baseIV // Return original IV as fallback + return baseIV, 0 // Return original IV as fallback } // Create a copy of the base IV to avoid modifying the original iv := make([]byte, 16) copy(iv, baseIV) - // Calculate the block offset (AES block size is 16 bytes) + // Calculate the block offset (AES block size is 16 bytes) and intra-block skip blockOffset := offset / 16 + skip := int(offset % 16) originalBlockOffset := blockOffset // Add the block offset to the IV counter (last 8 bytes, big-endian) @@ -36,7 +39,7 @@ func calculateIVWithOffset(baseIV []byte, offset int64) []byte { } // Single consolidated debug log to avoid performance impact in high-throughput scenarios - glog.V(4).Infof("calculateIVWithOffset: baseIV=%x, offset=%d, blockOffset=%d, derivedIV=%x", - baseIV, offset, originalBlockOffset, iv) - return iv + glog.V(4).Infof("calculateIVWithOffset: baseIV=%x, offset=%d, blockOffset=%d, skip=%d, derivedIV=%x", + baseIV, offset, originalBlockOffset, skip, iv) + return iv, skip } |