1272 lines
42 KiB
Go
1272 lines
42 KiB
Go
/*
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* Minio Cloud Storage, (C) 2017, 2018 Minio, Inc.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package cmd
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import (
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"context"
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"crypto/hmac"
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"crypto/rand"
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"crypto/subtle"
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"encoding/binary"
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"encoding/hex"
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"errors"
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"io"
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"net/http"
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"path"
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"strconv"
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"github.com/minio/minio-go/pkg/encrypt"
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"github.com/minio/minio/cmd/crypto"
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"github.com/minio/minio/cmd/logger"
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"github.com/minio/minio/pkg/ioutil"
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sha256 "github.com/minio/sha256-simd"
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"github.com/minio/sio"
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)
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var (
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// AWS errors for invalid SSE-C requests.
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errEncryptedObject = errors.New("The object was stored using a form of SSE")
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errInvalidSSEParameters = errors.New("The SSE-C key for key-rotation is not correct") // special access denied
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errKMSNotConfigured = errors.New("KMS not configured for a server side encrypted object")
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// Additional Minio errors for SSE-C requests.
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errObjectTampered = errors.New("The requested object was modified and may be compromised")
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// error returned when invalid encryption parameters are specified
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errInvalidEncryptionParameters = errors.New("The encryption parameters are not applicable to this object")
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)
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const (
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// SSECustomerKeySize is the size of valid client provided encryption keys in bytes.
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// Currently AWS supports only AES256. So the SSE-C key size is fixed to 32 bytes.
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SSECustomerKeySize = 32
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// SSEIVSize is the size of the IV data
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SSEIVSize = 32 // 32 bytes
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// SSEDAREPackageBlockSize - SSE dare package block size.
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SSEDAREPackageBlockSize = 64 * 1024 // 64KiB bytes
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// SSEDAREPackageMetaSize - SSE dare package meta padding bytes.
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SSEDAREPackageMetaSize = 32 // 32 bytes
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)
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const (
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// SSESealAlgorithmDareSha256 specifies DARE as authenticated en/decryption scheme and SHA256 as cryptographic
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// hash function. The key derivation of DARE-SHA256 is not optimal and does not include the object path.
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// It is considered legacy and should not be used anymore.
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SSESealAlgorithmDareSha256 = "DARE-SHA256"
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// SSESealAlgorithmDareV2HmacSha256 specifies DAREv2 as authenticated en/decryption scheme and SHA256 as cryptographic
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// hash function for the HMAC PRF.
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SSESealAlgorithmDareV2HmacSha256 = "DAREv2-HMAC-SHA256"
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)
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// hasServerSideEncryptionHeader returns true if the given HTTP header
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// contains server-side-encryption.
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func hasServerSideEncryptionHeader(header http.Header) bool {
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return crypto.S3.IsRequested(header) || crypto.SSEC.IsRequested(header)
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}
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// isEncryptedMultipart returns true if the current object is
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// uploaded by the user using multipart mechanism:
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// initiate new multipart, upload part, complete upload
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func isEncryptedMultipart(objInfo ObjectInfo) bool {
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if len(objInfo.Parts) == 0 {
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return false
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}
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if !crypto.IsMultiPart(objInfo.UserDefined) {
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return false
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}
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for _, part := range objInfo.Parts {
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_, err := sio.DecryptedSize(uint64(part.Size))
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if err != nil {
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return false
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}
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}
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// Further check if this object is uploaded using multipart mechanism
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// by the user and it is not about XL internally splitting the
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// object into parts in PutObject()
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return !(objInfo.backendType == BackendErasure && len(objInfo.ETag) == 32)
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}
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// ParseSSECopyCustomerRequest parses the SSE-C header fields of the provided request.
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// It returns the client provided key on success.
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func ParseSSECopyCustomerRequest(h http.Header, metadata map[string]string) (key []byte, err error) {
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if crypto.S3.IsEncrypted(metadata) && crypto.SSECopy.IsRequested(h) {
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return nil, crypto.ErrIncompatibleEncryptionMethod
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}
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k, err := crypto.SSECopy.ParseHTTP(h)
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return k[:], err
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}
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// ParseSSECustomerRequest parses the SSE-C header fields of the provided request.
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// It returns the client provided key on success.
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func ParseSSECustomerRequest(r *http.Request) (key []byte, err error) {
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return ParseSSECustomerHeader(r.Header)
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}
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// ParseSSECustomerHeader parses the SSE-C header fields and returns
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// the client provided key on success.
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func ParseSSECustomerHeader(header http.Header) (key []byte, err error) {
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if crypto.S3.IsRequested(header) && crypto.SSEC.IsRequested(header) {
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return key, crypto.ErrIncompatibleEncryptionMethod
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}
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k, err := crypto.SSEC.ParseHTTP(header)
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return k[:], err
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}
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// This function rotates old to new key.
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func rotateKey(oldKey []byte, newKey []byte, bucket, object string, metadata map[string]string) error {
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switch {
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default:
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return errObjectTampered
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case crypto.SSEC.IsEncrypted(metadata):
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sealedKey, err := crypto.SSEC.ParseMetadata(metadata)
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if err != nil {
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return err
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}
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var objectKey crypto.ObjectKey
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var extKey [32]byte
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copy(extKey[:], oldKey)
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if err = objectKey.Unseal(extKey, sealedKey, crypto.SSEC.String(), bucket, object); err != nil {
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if subtle.ConstantTimeCompare(oldKey, newKey) == 1 {
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return errInvalidSSEParameters // AWS returns special error for equal but invalid keys.
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}
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return crypto.ErrInvalidCustomerKey // To provide strict AWS S3 compatibility we return: access denied.
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}
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if subtle.ConstantTimeCompare(oldKey, newKey) == 1 && sealedKey.Algorithm == crypto.SealAlgorithm {
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return nil // don't rotate on equal keys if seal algorithm is latest
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}
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copy(extKey[:], newKey)
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sealedKey = objectKey.Seal(extKey, sealedKey.IV, crypto.SSEC.String(), bucket, object)
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crypto.SSEC.CreateMetadata(metadata, sealedKey)
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return nil
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case crypto.S3.IsEncrypted(metadata):
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if GlobalKMS == nil {
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return errKMSNotConfigured
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}
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keyID, kmsKey, sealedKey, err := crypto.S3.ParseMetadata(metadata)
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if err != nil {
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return err
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}
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oldKey, err := GlobalKMS.UnsealKey(keyID, kmsKey, crypto.Context{bucket: path.Join(bucket, object)})
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if err != nil {
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return err
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}
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var objectKey crypto.ObjectKey
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if err = objectKey.Unseal(oldKey, sealedKey, crypto.S3.String(), bucket, object); err != nil {
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return err
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}
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newKey, encKey, err := GlobalKMS.GenerateKey(globalKMSKeyID, crypto.Context{bucket: path.Join(bucket, object)})
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if err != nil {
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return err
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}
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sealedKey = objectKey.Seal(newKey, crypto.GenerateIV(rand.Reader), crypto.S3.String(), bucket, object)
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crypto.S3.CreateMetadata(metadata, globalKMSKeyID, encKey, sealedKey)
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return nil
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}
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}
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func newEncryptMetadata(key []byte, bucket, object string, metadata map[string]string, sseS3 bool) ([]byte, error) {
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var sealedKey crypto.SealedKey
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if sseS3 {
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if GlobalKMS == nil {
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return nil, errKMSNotConfigured
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}
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key, encKey, err := GlobalKMS.GenerateKey(globalKMSKeyID, crypto.Context{bucket: path.Join(bucket, object)})
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if err != nil {
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return nil, err
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}
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objectKey := crypto.GenerateKey(key, rand.Reader)
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sealedKey = objectKey.Seal(key, crypto.GenerateIV(rand.Reader), crypto.S3.String(), bucket, object)
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crypto.S3.CreateMetadata(metadata, globalKMSKeyID, encKey, sealedKey)
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return objectKey[:], nil
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}
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var extKey [32]byte
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copy(extKey[:], key)
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objectKey := crypto.GenerateKey(extKey, rand.Reader)
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sealedKey = objectKey.Seal(extKey, crypto.GenerateIV(rand.Reader), crypto.SSEC.String(), bucket, object)
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crypto.SSEC.CreateMetadata(metadata, sealedKey)
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return objectKey[:], nil
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}
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func newEncryptReader(content io.Reader, key []byte, bucket, object string, metadata map[string]string, sseS3 bool) (r io.Reader, encKey []byte, err error) {
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objectEncryptionKey, err := newEncryptMetadata(key, bucket, object, metadata, sseS3)
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if err != nil {
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return nil, encKey, err
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}
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reader, err := sio.EncryptReader(content, sio.Config{Key: objectEncryptionKey[:], MinVersion: sio.Version20})
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if err != nil {
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return nil, encKey, crypto.ErrInvalidCustomerKey
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}
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return reader, objectEncryptionKey, nil
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}
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// set new encryption metadata from http request headers for SSE-C and generated key from KMS in the case of
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// SSE-S3
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func setEncryptionMetadata(r *http.Request, bucket, object string, metadata map[string]string) (err error) {
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var (
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key []byte
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)
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if crypto.SSEC.IsRequested(r.Header) {
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key, err = ParseSSECustomerRequest(r)
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if err != nil {
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return
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}
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}
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_, err = newEncryptMetadata(key, bucket, object, metadata, crypto.S3.IsRequested(r.Header))
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return
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}
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// EncryptRequest takes the client provided content and encrypts the data
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// with the client provided key. It also marks the object as client-side-encrypted
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// and sets the correct headers.
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func EncryptRequest(content io.Reader, r *http.Request, bucket, object string, metadata map[string]string) (reader io.Reader, objEncKey []byte, err error) {
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var (
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key []byte
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)
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if crypto.S3.IsRequested(r.Header) && crypto.SSEC.IsRequested(r.Header) {
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return nil, objEncKey, crypto.ErrIncompatibleEncryptionMethod
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}
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if crypto.SSEC.IsRequested(r.Header) {
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key, err = ParseSSECustomerRequest(r)
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if err != nil {
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return nil, objEncKey, err
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}
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}
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return newEncryptReader(content, key, bucket, object, metadata, crypto.S3.IsRequested(r.Header))
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}
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// DecryptCopyRequest decrypts the object with the client provided key. It also removes
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// the client-side-encryption metadata from the object and sets the correct headers.
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func DecryptCopyRequest(client io.Writer, r *http.Request, bucket, object string, metadata map[string]string) (io.WriteCloser, error) {
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var (
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key []byte
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err error
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)
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if crypto.SSECopy.IsRequested(r.Header) {
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key, err = ParseSSECopyCustomerRequest(r.Header, metadata)
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if err != nil {
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return nil, err
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}
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}
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return newDecryptWriter(client, key, bucket, object, 0, metadata)
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}
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func decryptObjectInfo(key []byte, bucket, object string, metadata map[string]string) ([]byte, error) {
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switch {
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default:
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return nil, errObjectTampered
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case crypto.S3.IsEncrypted(metadata):
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if GlobalKMS == nil {
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return nil, errKMSNotConfigured
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}
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keyID, kmsKey, sealedKey, err := crypto.S3.ParseMetadata(metadata)
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if err != nil {
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return nil, err
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}
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extKey, err := GlobalKMS.UnsealKey(keyID, kmsKey, crypto.Context{bucket: path.Join(bucket, object)})
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if err != nil {
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return nil, err
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}
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var objectKey crypto.ObjectKey
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if err = objectKey.Unseal(extKey, sealedKey, crypto.S3.String(), bucket, object); err != nil {
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return nil, err
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}
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return objectKey[:], nil
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case crypto.SSEC.IsEncrypted(metadata):
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var extKey [32]byte
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copy(extKey[:], key)
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sealedKey, err := crypto.SSEC.ParseMetadata(metadata)
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if err != nil {
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return nil, err
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}
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var objectKey crypto.ObjectKey
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if err = objectKey.Unseal(extKey, sealedKey, crypto.SSEC.String(), bucket, object); err != nil {
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return nil, err
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}
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return objectKey[:], nil
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}
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}
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func newDecryptWriter(client io.Writer, key []byte, bucket, object string, seqNumber uint32, metadata map[string]string) (io.WriteCloser, error) {
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objectEncryptionKey, err := decryptObjectInfo(key, bucket, object, metadata)
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if err != nil {
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return nil, err
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}
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return newDecryptWriterWithObjectKey(client, objectEncryptionKey, seqNumber, metadata)
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}
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func newDecryptWriterWithObjectKey(client io.Writer, objectEncryptionKey []byte, seqNumber uint32, metadata map[string]string) (io.WriteCloser, error) {
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writer, err := sio.DecryptWriter(client, sio.Config{
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Key: objectEncryptionKey,
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SequenceNumber: seqNumber,
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})
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if err != nil {
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return nil, crypto.ErrInvalidCustomerKey
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}
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delete(metadata, crypto.SSEIV)
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delete(metadata, crypto.SSESealAlgorithm)
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delete(metadata, crypto.SSECSealedKey)
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delete(metadata, crypto.SSEMultipart)
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delete(metadata, crypto.S3SealedKey)
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delete(metadata, crypto.S3KMSSealedKey)
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delete(metadata, crypto.S3KMSKeyID)
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return writer, nil
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}
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// Adding support for reader based interface
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// DecryptRequestWithSequenceNumberR - same as
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// DecryptRequestWithSequenceNumber but with a reader
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func DecryptRequestWithSequenceNumberR(client io.Reader, h http.Header, bucket, object string, seqNumber uint32, metadata map[string]string) (io.Reader, error) {
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if crypto.S3.IsEncrypted(metadata) {
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return newDecryptReader(client, nil, bucket, object, seqNumber, metadata)
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}
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key, err := ParseSSECustomerHeader(h)
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if err != nil {
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return nil, err
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}
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return newDecryptReader(client, key, bucket, object, seqNumber, metadata)
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}
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// DecryptCopyRequestR - same as DecryptCopyRequest, but with a
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// Reader
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func DecryptCopyRequestR(client io.Reader, h http.Header, bucket, object string, seqNumber uint32, metadata map[string]string) (io.Reader, error) {
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var (
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key []byte
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err error
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)
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if crypto.SSECopy.IsRequested(h) {
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key, err = ParseSSECopyCustomerRequest(h, metadata)
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if err != nil {
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return nil, err
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}
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}
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return newDecryptReader(client, key, bucket, object, seqNumber, metadata)
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}
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func newDecryptReader(client io.Reader, key []byte, bucket, object string, seqNumber uint32, metadata map[string]string) (io.Reader, error) {
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objectEncryptionKey, err := decryptObjectInfo(key, bucket, object, metadata)
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if err != nil {
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return nil, err
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}
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return newDecryptReaderWithObjectKey(client, objectEncryptionKey, seqNumber, metadata)
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}
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func newDecryptReaderWithObjectKey(client io.Reader, objectEncryptionKey []byte, seqNumber uint32, metadata map[string]string) (io.Reader, error) {
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reader, err := sio.DecryptReader(client, sio.Config{
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Key: objectEncryptionKey,
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SequenceNumber: seqNumber,
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})
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if err != nil {
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return nil, crypto.ErrInvalidCustomerKey
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}
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return reader, nil
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}
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|
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// DecryptBlocksRequestR - same as DecryptBlocksRequest but with a
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// reader
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func DecryptBlocksRequestR(inputReader io.Reader, h http.Header, offset,
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length int64, seqNumber uint32, partStart int, oi ObjectInfo, copySource bool) (
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io.Reader, error) {
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bucket, object := oi.Bucket, oi.Name
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// Single part case
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if !isEncryptedMultipart(oi) {
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var reader io.Reader
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var err error
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if copySource {
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reader, err = DecryptCopyRequestR(inputReader, h, bucket, object, seqNumber, oi.UserDefined)
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} else {
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reader, err = DecryptRequestWithSequenceNumberR(inputReader, h, bucket, object, seqNumber, oi.UserDefined)
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}
|
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if err != nil {
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return nil, err
|
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}
|
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return reader, nil
|
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}
|
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|
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partDecRelOffset := int64(seqNumber) * SSEDAREPackageBlockSize
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partEncRelOffset := int64(seqNumber) * (SSEDAREPackageBlockSize + SSEDAREPackageMetaSize)
|
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w := &DecryptBlocksReader{
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reader: inputReader,
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startSeqNum: seqNumber,
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partDecRelOffset: partDecRelOffset,
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partEncRelOffset: partEncRelOffset,
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parts: oi.Parts,
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partIndex: partStart,
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header: h,
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bucket: bucket,
|
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object: object,
|
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customerKeyHeader: h.Get(crypto.SSECKey),
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copySource: copySource,
|
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}
|
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|
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w.metadata = map[string]string{}
|
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// Copy encryption metadata for internal use.
|
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for k, v := range oi.UserDefined {
|
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w.metadata[k] = v
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}
|
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|
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if w.copySource {
|
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w.customerKeyHeader = h.Get(crypto.SSECopyKey)
|
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}
|
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|
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if err := w.buildDecrypter(w.parts[w.partIndex].Number); err != nil {
|
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return nil, err
|
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}
|
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|
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return w, nil
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}
|
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|
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// DecryptRequestWithSequenceNumber decrypts the object with the client provided key. It also removes
|
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// the client-side-encryption metadata from the object and sets the correct headers.
|
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func DecryptRequestWithSequenceNumber(client io.Writer, r *http.Request, bucket, object string, seqNumber uint32, metadata map[string]string) (io.WriteCloser, error) {
|
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if crypto.S3.IsEncrypted(metadata) {
|
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return newDecryptWriter(client, nil, bucket, object, seqNumber, metadata)
|
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}
|
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|
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key, err := ParseSSECustomerRequest(r)
|
|
if err != nil {
|
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return nil, err
|
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}
|
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return newDecryptWriter(client, key, bucket, object, seqNumber, metadata)
|
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}
|
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|
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// DecryptRequest decrypts the object with client provided key for SSE-C and SSE-S3. It also removes
|
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// the encryption metadata from the object and sets the correct headers.
|
|
func DecryptRequest(client io.Writer, r *http.Request, bucket, object string, metadata map[string]string) (io.WriteCloser, error) {
|
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return DecryptRequestWithSequenceNumber(client, r, bucket, object, 0, metadata)
|
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}
|
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|
|
// DecryptBlocksReader - decrypts multipart parts, while implementing
|
|
// a io.Reader compatible interface.
|
|
type DecryptBlocksReader struct {
|
|
// Source of the encrypted content that will be decrypted
|
|
reader io.Reader
|
|
// Current decrypter for the current encrypted data block
|
|
decrypter io.Reader
|
|
// Start sequence number
|
|
startSeqNum uint32
|
|
// Current part index
|
|
partIndex int
|
|
// Parts information
|
|
parts []ObjectPartInfo
|
|
header http.Header
|
|
bucket, object string
|
|
metadata map[string]string
|
|
|
|
partDecRelOffset, partEncRelOffset int64
|
|
|
|
copySource bool
|
|
// Customer Key
|
|
customerKeyHeader string
|
|
}
|
|
|
|
func (d *DecryptBlocksReader) buildDecrypter(partID int) error {
|
|
m := make(map[string]string)
|
|
for k, v := range d.metadata {
|
|
m[k] = v
|
|
}
|
|
// Initialize the first decrypter; new decrypters will be
|
|
// initialized in Read() operation as needed.
|
|
var key []byte
|
|
var err error
|
|
if d.copySource {
|
|
if crypto.SSEC.IsEncrypted(d.metadata) {
|
|
d.header.Set(crypto.SSECopyKey, d.customerKeyHeader)
|
|
key, err = ParseSSECopyCustomerRequest(d.header, d.metadata)
|
|
}
|
|
} else {
|
|
if crypto.SSEC.IsEncrypted(d.metadata) {
|
|
d.header.Set(crypto.SSECKey, d.customerKeyHeader)
|
|
key, err = ParseSSECustomerHeader(d.header)
|
|
}
|
|
}
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
objectEncryptionKey, err := decryptObjectInfo(key, d.bucket, d.object, m)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
var partIDbin [4]byte
|
|
binary.LittleEndian.PutUint32(partIDbin[:], uint32(partID)) // marshal part ID
|
|
|
|
mac := hmac.New(sha256.New, objectEncryptionKey) // derive part encryption key from part ID and object key
|
|
mac.Write(partIDbin[:])
|
|
partEncryptionKey := mac.Sum(nil)
|
|
|
|
// Limit the reader, so the decryptor doesnt receive bytes
|
|
// from the next part (different DARE stream)
|
|
encLenToRead := d.parts[d.partIndex].Size - d.partEncRelOffset
|
|
decrypter, err := newDecryptReaderWithObjectKey(io.LimitReader(d.reader, encLenToRead), partEncryptionKey, d.startSeqNum, m)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
d.decrypter = decrypter
|
|
return nil
|
|
}
|
|
|
|
func (d *DecryptBlocksReader) Read(p []byte) (int, error) {
|
|
var err error
|
|
var n1 int
|
|
decPartSize, _ := sio.DecryptedSize(uint64(d.parts[d.partIndex].Size))
|
|
unreadPartLen := int64(decPartSize) - d.partDecRelOffset
|
|
if int64(len(p)) < unreadPartLen {
|
|
n1, err = d.decrypter.Read(p)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
d.partDecRelOffset += int64(n1)
|
|
} else {
|
|
n1, err = io.ReadFull(d.decrypter, p[:unreadPartLen])
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
// We should now proceed to next part, reset all
|
|
// values appropriately.
|
|
d.partEncRelOffset = 0
|
|
d.partDecRelOffset = 0
|
|
d.startSeqNum = 0
|
|
|
|
d.partIndex++
|
|
if d.partIndex == len(d.parts) {
|
|
return n1, io.EOF
|
|
}
|
|
|
|
err = d.buildDecrypter(d.parts[d.partIndex].Number)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
n1, err = d.decrypter.Read(p[n1:])
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
d.partDecRelOffset += int64(n1)
|
|
}
|
|
return len(p), nil
|
|
}
|
|
|
|
// DecryptBlocksWriter - decrypts multipart parts, while implementing
|
|
// a io.Writer compatible interface.
|
|
type DecryptBlocksWriter struct {
|
|
// Original writer where the plain data will be written
|
|
writer io.Writer
|
|
// Current decrypter for the current encrypted data block
|
|
decrypter io.WriteCloser
|
|
// Start sequence number
|
|
startSeqNum uint32
|
|
// Current part index
|
|
partIndex int
|
|
// Parts information
|
|
parts []ObjectPartInfo
|
|
req *http.Request
|
|
bucket, object string
|
|
metadata map[string]string
|
|
|
|
partEncRelOffset int64
|
|
|
|
copySource bool
|
|
// Customer Key
|
|
customerKeyHeader string
|
|
}
|
|
|
|
func (w *DecryptBlocksWriter) buildDecrypter(partID int) error {
|
|
m := make(map[string]string)
|
|
for k, v := range w.metadata {
|
|
m[k] = v
|
|
}
|
|
// Initialize the first decrypter, new decrypters will be initialized in Write() operation as needed.
|
|
var key []byte
|
|
var err error
|
|
if w.copySource {
|
|
if crypto.SSEC.IsEncrypted(w.metadata) {
|
|
w.req.Header.Set(crypto.SSECopyKey, w.customerKeyHeader)
|
|
key, err = ParseSSECopyCustomerRequest(w.req.Header, w.metadata)
|
|
}
|
|
} else {
|
|
if crypto.SSEC.IsEncrypted(w.metadata) {
|
|
w.req.Header.Set(crypto.SSECKey, w.customerKeyHeader)
|
|
key, err = ParseSSECustomerRequest(w.req)
|
|
}
|
|
}
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
objectEncryptionKey, err := decryptObjectInfo(key, w.bucket, w.object, m)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
var partIDbin [4]byte
|
|
binary.LittleEndian.PutUint32(partIDbin[:], uint32(partID)) // marshal part ID
|
|
|
|
mac := hmac.New(sha256.New, objectEncryptionKey) // derive part encryption key from part ID and object key
|
|
mac.Write(partIDbin[:])
|
|
partEncryptionKey := mac.Sum(nil)
|
|
|
|
// make sure to provide a NopCloser such that a Close
|
|
// on sio.decryptWriter doesn't close the underlying writer's
|
|
// close which perhaps can close the stream prematurely.
|
|
decrypter, err := newDecryptWriterWithObjectKey(ioutil.NopCloser(w.writer), partEncryptionKey, w.startSeqNum, m)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if w.decrypter != nil {
|
|
// Pro-actively close the writer such that any pending buffers
|
|
// are flushed already before we allocate a new decrypter.
|
|
err = w.decrypter.Close()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
w.decrypter = decrypter
|
|
return nil
|
|
}
|
|
|
|
func (w *DecryptBlocksWriter) Write(p []byte) (int, error) {
|
|
var err error
|
|
var n1 int
|
|
if int64(len(p)) < w.parts[w.partIndex].Size-w.partEncRelOffset {
|
|
n1, err = w.decrypter.Write(p)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
w.partEncRelOffset += int64(n1)
|
|
} else {
|
|
n1, err = w.decrypter.Write(p[:w.parts[w.partIndex].Size-w.partEncRelOffset])
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
// We should now proceed to next part, reset all values appropriately.
|
|
w.partEncRelOffset = 0
|
|
w.startSeqNum = 0
|
|
|
|
w.partIndex++
|
|
|
|
err = w.buildDecrypter(w.partIndex + 1)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
n1, err = w.decrypter.Write(p[n1:])
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
w.partEncRelOffset += int64(n1)
|
|
}
|
|
|
|
return len(p), nil
|
|
}
|
|
|
|
// Close closes the LimitWriter. It behaves like io.Closer.
|
|
func (w *DecryptBlocksWriter) Close() error {
|
|
if w.decrypter != nil {
|
|
err := w.decrypter.Close()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
if closer, ok := w.writer.(io.Closer); ok {
|
|
return closer.Close()
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// DecryptAllBlocksCopyRequest - setup a struct which can decrypt many concatenated encrypted data
|
|
// parts information helps to know the boundaries of each encrypted data block, this function decrypts
|
|
// all parts starting from part-1.
|
|
func DecryptAllBlocksCopyRequest(client io.Writer, r *http.Request, bucket, object string, objInfo ObjectInfo) (io.WriteCloser, int64, error) {
|
|
w, _, size, err := DecryptBlocksRequest(client, r, bucket, object, 0, objInfo.Size, objInfo, true)
|
|
return w, size, err
|
|
}
|
|
|
|
// DecryptBlocksRequest - setup a struct which can decrypt many concatenated encrypted data
|
|
// parts information helps to know the boundaries of each encrypted data block.
|
|
func DecryptBlocksRequest(client io.Writer, r *http.Request, bucket, object string, startOffset, length int64, objInfo ObjectInfo, copySource bool) (io.WriteCloser, int64, int64, error) {
|
|
var seqNumber uint32
|
|
var encStartOffset, encLength int64
|
|
|
|
if !isEncryptedMultipart(objInfo) {
|
|
seqNumber, encStartOffset, encLength = getEncryptedSinglePartOffsetLength(startOffset, length, objInfo)
|
|
|
|
var writer io.WriteCloser
|
|
var err error
|
|
if copySource {
|
|
writer, err = DecryptCopyRequest(client, r, bucket, object, objInfo.UserDefined)
|
|
} else {
|
|
writer, err = DecryptRequestWithSequenceNumber(client, r, bucket, object, seqNumber, objInfo.UserDefined)
|
|
}
|
|
if err != nil {
|
|
return nil, 0, 0, err
|
|
}
|
|
return writer, encStartOffset, encLength, nil
|
|
}
|
|
|
|
_, encStartOffset, encLength = getEncryptedMultipartsOffsetLength(startOffset, length, objInfo)
|
|
|
|
var partStartIndex int
|
|
var partStartOffset = startOffset
|
|
// Skip parts until final offset maps to a particular part offset.
|
|
for i, part := range objInfo.Parts {
|
|
decryptedSize, err := sio.DecryptedSize(uint64(part.Size))
|
|
if err != nil {
|
|
return nil, -1, -1, errObjectTampered
|
|
}
|
|
|
|
partStartIndex = i
|
|
|
|
// Offset is smaller than size we have reached the
|
|
// proper part offset, break out we start from
|
|
// this part index.
|
|
if partStartOffset < int64(decryptedSize) {
|
|
break
|
|
}
|
|
|
|
// Continue to look for next part.
|
|
partStartOffset -= int64(decryptedSize)
|
|
}
|
|
|
|
startSeqNum := partStartOffset / SSEDAREPackageBlockSize
|
|
partEncRelOffset := int64(startSeqNum) * (SSEDAREPackageBlockSize + SSEDAREPackageMetaSize)
|
|
|
|
w := &DecryptBlocksWriter{
|
|
writer: client,
|
|
startSeqNum: uint32(startSeqNum),
|
|
partEncRelOffset: partEncRelOffset,
|
|
parts: objInfo.Parts,
|
|
partIndex: partStartIndex,
|
|
req: r,
|
|
bucket: bucket,
|
|
object: object,
|
|
customerKeyHeader: r.Header.Get(crypto.SSECKey),
|
|
copySource: copySource,
|
|
}
|
|
|
|
w.metadata = map[string]string{}
|
|
// Copy encryption metadata for internal use.
|
|
for k, v := range objInfo.UserDefined {
|
|
w.metadata[k] = v
|
|
}
|
|
|
|
// Purge all the encryption headers.
|
|
delete(objInfo.UserDefined, crypto.SSEIV)
|
|
delete(objInfo.UserDefined, crypto.SSESealAlgorithm)
|
|
delete(objInfo.UserDefined, crypto.SSECSealedKey)
|
|
delete(objInfo.UserDefined, crypto.SSEMultipart)
|
|
|
|
if crypto.S3.IsEncrypted(objInfo.UserDefined) {
|
|
delete(objInfo.UserDefined, crypto.S3SealedKey)
|
|
delete(objInfo.UserDefined, crypto.S3KMSKeyID)
|
|
delete(objInfo.UserDefined, crypto.S3KMSSealedKey)
|
|
}
|
|
if w.copySource {
|
|
w.customerKeyHeader = r.Header.Get(crypto.SSECopyKey)
|
|
}
|
|
|
|
if err := w.buildDecrypter(w.parts[w.partIndex].Number); err != nil {
|
|
return nil, 0, 0, err
|
|
}
|
|
|
|
return w, encStartOffset, encLength, nil
|
|
}
|
|
|
|
// getEncryptedMultipartsOffsetLength - fetch sequence number, encrypted start offset and encrypted length.
|
|
func getEncryptedMultipartsOffsetLength(offset, length int64, obj ObjectInfo) (uint32, int64, int64) {
|
|
// Calculate encrypted offset of a multipart object
|
|
computeEncOffset := func(off int64, obj ObjectInfo) (seqNumber uint32, encryptedOffset int64, err error) {
|
|
var curPartEndOffset uint64
|
|
var prevPartsEncSize int64
|
|
for _, p := range obj.Parts {
|
|
size, decErr := sio.DecryptedSize(uint64(p.Size))
|
|
if decErr != nil {
|
|
err = errObjectTampered // assign correct error type
|
|
return
|
|
}
|
|
if off < int64(curPartEndOffset+size) {
|
|
seqNumber, encryptedOffset, _ = getEncryptedSinglePartOffsetLength(off-int64(curPartEndOffset), 1, obj)
|
|
encryptedOffset += int64(prevPartsEncSize)
|
|
break
|
|
}
|
|
curPartEndOffset += size
|
|
prevPartsEncSize += p.Size
|
|
}
|
|
return
|
|
}
|
|
|
|
// Calculate the encrypted start offset corresponding to the plain offset
|
|
seqNumber, encStartOffset, _ := computeEncOffset(offset, obj)
|
|
// Calculate also the encrypted end offset corresponding to plain offset + plain length
|
|
_, encEndOffset, _ := computeEncOffset(offset+length-1, obj)
|
|
|
|
// encLength is the diff between encrypted end offset and encrypted start offset + one package size
|
|
// to ensure all encrypted data are covered
|
|
encLength := encEndOffset - encStartOffset + (64*1024 + 32)
|
|
|
|
// Calculate total size of all parts
|
|
var totalPartsLength int64
|
|
for _, p := range obj.Parts {
|
|
totalPartsLength += p.Size
|
|
}
|
|
|
|
// Set encLength to maximum possible value if it exceeded total parts size
|
|
if encLength+encStartOffset > totalPartsLength {
|
|
encLength = totalPartsLength - encStartOffset
|
|
}
|
|
|
|
return seqNumber, encStartOffset, encLength
|
|
}
|
|
|
|
// getEncryptedSinglePartOffsetLength - fetch sequence number, encrypted start offset and encrypted length.
|
|
func getEncryptedSinglePartOffsetLength(offset, length int64, objInfo ObjectInfo) (seqNumber uint32, encOffset int64, encLength int64) {
|
|
onePkgSize := int64(SSEDAREPackageBlockSize + SSEDAREPackageMetaSize)
|
|
|
|
seqNumber = uint32(offset / SSEDAREPackageBlockSize)
|
|
encOffset = int64(seqNumber) * onePkgSize
|
|
// The math to compute the encrypted length is always
|
|
// originalLength i.e (offset+length-1) to be divided under
|
|
// 64KiB blocks which is the payload size for each encrypted
|
|
// block. This is then multiplied by final package size which
|
|
// is basically 64KiB + 32. Finally negate the encrypted offset
|
|
// to get the final encrypted length on disk.
|
|
encLength = ((offset+length)/SSEDAREPackageBlockSize)*onePkgSize - encOffset
|
|
|
|
// Check for the remainder, to figure if we need one extract package to read from.
|
|
if (offset+length)%SSEDAREPackageBlockSize > 0 {
|
|
encLength += onePkgSize
|
|
}
|
|
|
|
if encLength+encOffset > objInfo.EncryptedSize() {
|
|
encLength = objInfo.EncryptedSize() - encOffset
|
|
}
|
|
return seqNumber, encOffset, encLength
|
|
}
|
|
|
|
// DecryptedSize returns the size of the object after decryption in bytes.
|
|
// It returns an error if the object is not encrypted or marked as encrypted
|
|
// but has an invalid size.
|
|
func (o *ObjectInfo) DecryptedSize() (int64, error) {
|
|
if !crypto.IsEncrypted(o.UserDefined) {
|
|
return 0, errors.New("Cannot compute decrypted size of an unencrypted object")
|
|
}
|
|
if !isEncryptedMultipart(*o) {
|
|
size, err := sio.DecryptedSize(uint64(o.Size))
|
|
if err != nil {
|
|
err = errObjectTampered // assign correct error type
|
|
}
|
|
return int64(size), err
|
|
}
|
|
|
|
var size int64
|
|
for _, part := range o.Parts {
|
|
partSize, err := sio.DecryptedSize(uint64(part.Size))
|
|
if err != nil {
|
|
return 0, errObjectTampered
|
|
}
|
|
size += int64(partSize)
|
|
}
|
|
return size, nil
|
|
}
|
|
|
|
// For encrypted objects, the ETag sent by client if available
|
|
// is stored in encrypted form in the backend. Decrypt the ETag
|
|
// if ETag was previously encrypted.
|
|
func getDecryptedETag(headers http.Header, objInfo ObjectInfo, copySource bool) (decryptedETag string) {
|
|
var (
|
|
key [32]byte
|
|
err error
|
|
)
|
|
// If ETag is contentMD5Sum return it as is.
|
|
if len(objInfo.ETag) == 32 {
|
|
return objInfo.ETag
|
|
}
|
|
|
|
if crypto.IsMultiPart(objInfo.UserDefined) {
|
|
return objInfo.ETag
|
|
}
|
|
if crypto.SSECopy.IsRequested(headers) {
|
|
key, err = crypto.SSECopy.ParseHTTP(headers)
|
|
if err != nil {
|
|
return objInfo.ETag
|
|
}
|
|
}
|
|
// As per AWS S3 Spec, ETag for SSE-C encrypted objects need not be MD5Sum of the data.
|
|
// Since server side copy with same source and dest just replaces the ETag, we save
|
|
// encrypted content MD5Sum as ETag for both SSE-C and SSE-S3, we standardize the ETag
|
|
//encryption across SSE-C and SSE-S3, and only return last 32 bytes for SSE-C
|
|
if crypto.SSEC.IsEncrypted(objInfo.UserDefined) && !copySource {
|
|
return objInfo.ETag[len(objInfo.ETag)-32:]
|
|
}
|
|
|
|
objectEncryptionKey, err := decryptObjectInfo(key[:], objInfo.Bucket, objInfo.Name, objInfo.UserDefined)
|
|
if err != nil {
|
|
return objInfo.ETag
|
|
}
|
|
return tryDecryptETag(objectEncryptionKey, objInfo.ETag, false)
|
|
}
|
|
|
|
// helper to decrypt Etag given object encryption key and encrypted ETag
|
|
func tryDecryptETag(key []byte, encryptedETag string, ssec bool) string {
|
|
// ETag for SSE-C encrypted objects need not be content MD5Sum.While encrypted
|
|
// md5sum is stored internally, return just the last 32 bytes of hex-encoded and
|
|
// encrypted md5sum string for SSE-C
|
|
if ssec {
|
|
return encryptedETag[len(encryptedETag)-32:]
|
|
}
|
|
var objectKey crypto.ObjectKey
|
|
copy(objectKey[:], key)
|
|
encBytes, err := hex.DecodeString(encryptedETag)
|
|
if err != nil {
|
|
return encryptedETag
|
|
}
|
|
etagBytes, err := objectKey.UnsealETag(encBytes)
|
|
if err != nil {
|
|
return encryptedETag
|
|
}
|
|
return hex.EncodeToString(etagBytes)
|
|
}
|
|
|
|
// GetDecryptedRange - To decrypt the range (off, length) of the
|
|
// decrypted object stream, we need to read the range (encOff,
|
|
// encLength) of the encrypted object stream to decrypt it, and
|
|
// compute skipLen, the number of bytes to skip in the beginning of
|
|
// the encrypted range.
|
|
//
|
|
// In addition we also compute the object part number for where the
|
|
// requested range starts, along with the DARE sequence number within
|
|
// that part. For single part objects, the partStart will be 0.
|
|
func (o *ObjectInfo) GetDecryptedRange(rs *HTTPRangeSpec) (encOff, encLength, skipLen int64, seqNumber uint32, partStart int, err error) {
|
|
if !crypto.IsEncrypted(o.UserDefined) {
|
|
err = errors.New("Object is not encrypted")
|
|
return
|
|
}
|
|
|
|
if rs == nil {
|
|
// No range, so offsets refer to the whole object.
|
|
return 0, int64(o.Size), 0, 0, 0, nil
|
|
}
|
|
|
|
// Assemble slice of (decrypted) part sizes in `sizes`
|
|
var sizes []int64
|
|
var decObjSize int64 // decrypted total object size
|
|
if isEncryptedMultipart(*o) {
|
|
sizes = make([]int64, len(o.Parts))
|
|
for i, part := range o.Parts {
|
|
var partSize uint64
|
|
partSize, err = sio.DecryptedSize(uint64(part.Size))
|
|
if err != nil {
|
|
err = errObjectTampered
|
|
return
|
|
}
|
|
sizes[i] = int64(partSize)
|
|
decObjSize += int64(partSize)
|
|
}
|
|
} else {
|
|
var partSize uint64
|
|
partSize, err = sio.DecryptedSize(uint64(o.Size))
|
|
if err != nil {
|
|
err = errObjectTampered
|
|
return
|
|
}
|
|
sizes = []int64{int64(partSize)}
|
|
decObjSize = sizes[0]
|
|
}
|
|
|
|
var off, length int64
|
|
off, length, err = rs.GetOffsetLength(decObjSize)
|
|
if err != nil {
|
|
return
|
|
}
|
|
|
|
// At this point, we have:
|
|
//
|
|
// 1. the decrypted part sizes in `sizes` (single element for
|
|
// single part object) and total decrypted object size `decObjSize`
|
|
//
|
|
// 2. the (decrypted) start offset `off` and (decrypted)
|
|
// length to read `length`
|
|
//
|
|
// These are the inputs to the rest of the algorithm below.
|
|
|
|
// Locate the part containing the start of the required range
|
|
var partEnd int
|
|
var cumulativeSum, encCumulativeSum int64
|
|
for i, size := range sizes {
|
|
if off < cumulativeSum+size {
|
|
partStart = i
|
|
break
|
|
}
|
|
cumulativeSum += size
|
|
encPartSize, _ := sio.EncryptedSize(uint64(size))
|
|
encCumulativeSum += int64(encPartSize)
|
|
}
|
|
// partStart is always found in the loop above,
|
|
// because off is validated.
|
|
|
|
sseDAREEncPackageBlockSize := int64(SSEDAREPackageBlockSize + SSEDAREPackageMetaSize)
|
|
startPkgNum := (off - cumulativeSum) / SSEDAREPackageBlockSize
|
|
|
|
// Now we can calculate the number of bytes to skip
|
|
skipLen = (off - cumulativeSum) % SSEDAREPackageBlockSize
|
|
|
|
encOff = encCumulativeSum + startPkgNum*sseDAREEncPackageBlockSize
|
|
// Locate the part containing the end of the required range
|
|
endOffset := off + length - 1
|
|
for i1, size := range sizes[partStart:] {
|
|
i := partStart + i1
|
|
if endOffset < cumulativeSum+size {
|
|
partEnd = i
|
|
break
|
|
}
|
|
cumulativeSum += size
|
|
encPartSize, _ := sio.EncryptedSize(uint64(size))
|
|
encCumulativeSum += int64(encPartSize)
|
|
}
|
|
// partEnd is always found in the loop above, because off and
|
|
// length are validated.
|
|
endPkgNum := (endOffset - cumulativeSum) / SSEDAREPackageBlockSize
|
|
// Compute endEncOffset with one additional DARE package (so
|
|
// we read the package containing the last desired byte).
|
|
endEncOffset := encCumulativeSum + (endPkgNum+1)*sseDAREEncPackageBlockSize
|
|
// Check if the DARE package containing the end offset is a
|
|
// full sized package (as the last package in the part may be
|
|
// smaller)
|
|
lastPartSize, _ := sio.EncryptedSize(uint64(sizes[partEnd]))
|
|
if endEncOffset > encCumulativeSum+int64(lastPartSize) {
|
|
endEncOffset = encCumulativeSum + int64(lastPartSize)
|
|
}
|
|
encLength = endEncOffset - encOff
|
|
// Set the sequence number as the starting package number of
|
|
// the requested block
|
|
seqNumber = uint32(startPkgNum)
|
|
return encOff, encLength, skipLen, seqNumber, partStart, nil
|
|
}
|
|
|
|
// EncryptedSize returns the size of the object after encryption.
|
|
// An encrypted object is always larger than a plain object
|
|
// except for zero size objects.
|
|
func (o *ObjectInfo) EncryptedSize() int64 {
|
|
size, err := sio.EncryptedSize(uint64(o.Size))
|
|
if err != nil {
|
|
// This cannot happen since AWS S3 allows parts to be 5GB at most
|
|
// sio max. size is 256 TB
|
|
reqInfo := (&logger.ReqInfo{}).AppendTags("size", strconv.FormatUint(size, 10))
|
|
ctx := logger.SetReqInfo(context.Background(), reqInfo)
|
|
logger.CriticalIf(ctx, err)
|
|
}
|
|
return int64(size)
|
|
}
|
|
|
|
// DecryptCopyObjectInfo tries to decrypt the provided object if it is encrypted.
|
|
// It fails if the object is encrypted and the HTTP headers don't contain
|
|
// SSE-C headers or the object is not encrypted but SSE-C headers are provided. (AWS behavior)
|
|
// DecryptObjectInfo returns 'ErrNone' if the object is not encrypted or the
|
|
// decryption succeeded.
|
|
//
|
|
// DecryptCopyObjectInfo also returns whether the object is encrypted or not.
|
|
func DecryptCopyObjectInfo(info *ObjectInfo, headers http.Header) (errCode APIErrorCode, encrypted bool) {
|
|
// Directories are never encrypted.
|
|
if info.IsDir {
|
|
return ErrNone, false
|
|
}
|
|
if errCode, encrypted = ErrNone, crypto.IsEncrypted(info.UserDefined); !encrypted && crypto.SSECopy.IsRequested(headers) {
|
|
errCode = ErrInvalidEncryptionParameters
|
|
} else if encrypted {
|
|
if (!crypto.SSECopy.IsRequested(headers) && crypto.SSEC.IsEncrypted(info.UserDefined)) ||
|
|
(crypto.SSECopy.IsRequested(headers) && crypto.S3.IsEncrypted(info.UserDefined)) {
|
|
errCode = ErrSSEEncryptedObject
|
|
return
|
|
}
|
|
var err error
|
|
if info.Size, err = info.DecryptedSize(); err != nil {
|
|
errCode = toAPIErrorCode(context.Background(), err)
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
// DecryptObjectInfo tries to decrypt the provided object if it is encrypted.
|
|
// It fails if the object is encrypted and the HTTP headers don't contain
|
|
// SSE-C headers or the object is not encrypted but SSE-C headers are provided. (AWS behavior)
|
|
// DecryptObjectInfo returns 'ErrNone' if the object is not encrypted or the
|
|
// decryption succeeded.
|
|
//
|
|
// DecryptObjectInfo also returns whether the object is encrypted or not.
|
|
func DecryptObjectInfo(info *ObjectInfo, headers http.Header) (encrypted bool, err error) {
|
|
// Directories are never encrypted.
|
|
if info.IsDir {
|
|
return false, nil
|
|
}
|
|
// disallow X-Amz-Server-Side-Encryption header on HEAD and GET
|
|
if crypto.S3.IsRequested(headers) {
|
|
err = errInvalidEncryptionParameters
|
|
return
|
|
}
|
|
if err, encrypted = nil, crypto.IsEncrypted(info.UserDefined); !encrypted && crypto.SSEC.IsRequested(headers) {
|
|
err = errInvalidEncryptionParameters
|
|
} else if encrypted {
|
|
if (crypto.SSEC.IsEncrypted(info.UserDefined) && !crypto.SSEC.IsRequested(headers)) ||
|
|
(crypto.S3.IsEncrypted(info.UserDefined) && crypto.SSEC.IsRequested(headers)) {
|
|
err = errEncryptedObject
|
|
return
|
|
}
|
|
_, err = info.DecryptedSize()
|
|
|
|
if crypto.IsEncrypted(info.UserDefined) && !crypto.IsMultiPart(info.UserDefined) {
|
|
info.ETag = getDecryptedETag(headers, *info, false)
|
|
}
|
|
|
|
}
|
|
return
|
|
}
|
|
|
|
// The customer key in the header is used by the gateway for encryption in the case of
|
|
// s3 gateway double encryption. A new client key is derived from the customer provided
|
|
// key to be sent to the s3 backend for encryption at the backend.
|
|
func deriveClientKey(clientKey [32]byte, bucket, object string) [32]byte {
|
|
var key [32]byte
|
|
mac := hmac.New(sha256.New, clientKey[:])
|
|
mac.Write([]byte(crypto.SSEC.String()))
|
|
mac.Write([]byte(path.Join(bucket, object)))
|
|
mac.Sum(key[:0])
|
|
return key
|
|
}
|
|
|
|
// set encryption options for pass through to backend in the case of gateway and UserDefined metadata
|
|
func getDefaultOpts(header http.Header, copySource bool, metadata map[string]string) (opts ObjectOptions, err error) {
|
|
var clientKey [32]byte
|
|
var sse encrypt.ServerSide
|
|
|
|
if copySource {
|
|
if crypto.SSECopy.IsRequested(header) {
|
|
clientKey, err = crypto.SSECopy.ParseHTTP(header)
|
|
if err != nil {
|
|
return
|
|
}
|
|
if sse, err = encrypt.NewSSEC(clientKey[:]); err != nil {
|
|
return
|
|
}
|
|
return ObjectOptions{ServerSideEncryption: encrypt.SSECopy(sse), UserDefined: metadata}, nil
|
|
}
|
|
return
|
|
}
|
|
|
|
if crypto.SSEC.IsRequested(header) {
|
|
clientKey, err = crypto.SSEC.ParseHTTP(header)
|
|
if err != nil {
|
|
return
|
|
}
|
|
if sse, err = encrypt.NewSSEC(clientKey[:]); err != nil {
|
|
return
|
|
}
|
|
return ObjectOptions{ServerSideEncryption: sse, UserDefined: metadata}, nil
|
|
}
|
|
if crypto.S3.IsRequested(header) || (metadata != nil && crypto.S3.IsEncrypted(metadata)) {
|
|
return ObjectOptions{ServerSideEncryption: encrypt.NewSSE(), UserDefined: metadata}, nil
|
|
}
|
|
return ObjectOptions{UserDefined: metadata}, nil
|
|
}
|
|
|
|
// get ObjectOptions for GET calls from encryption headers
|
|
func getOpts(ctx context.Context, r *http.Request, bucket, object string) (ObjectOptions, error) {
|
|
var (
|
|
encryption encrypt.ServerSide
|
|
opts ObjectOptions
|
|
)
|
|
if GlobalGatewaySSE.SSEC() && crypto.SSEC.IsRequested(r.Header) {
|
|
key, err := crypto.SSEC.ParseHTTP(r.Header)
|
|
if err != nil {
|
|
return opts, err
|
|
}
|
|
derivedKey := deriveClientKey(key, bucket, object)
|
|
encryption, err = encrypt.NewSSEC(derivedKey[:])
|
|
logger.CriticalIf(ctx, err)
|
|
return ObjectOptions{ServerSideEncryption: encryption}, nil
|
|
}
|
|
// default case of passing encryption headers to backend
|
|
return getDefaultOpts(r.Header, false, nil)
|
|
}
|
|
|
|
// get ObjectOptions for PUT calls from encryption headers and metadata
|
|
func putOpts(ctx context.Context, r *http.Request, bucket, object string, metadata map[string]string) (opts ObjectOptions, err error) {
|
|
// In the case of multipart custom format, the metadata needs to be checked in addition to header to see if it
|
|
// is SSE-S3 encrypted, primarily because S3 protocol does not require SSE-S3 headers in PutObjectPart calls
|
|
if GlobalGatewaySSE.SSES3() && (crypto.S3.IsRequested(r.Header) || crypto.S3.IsEncrypted(metadata)) {
|
|
return ObjectOptions{ServerSideEncryption: encrypt.NewSSE(), UserDefined: metadata}, nil
|
|
}
|
|
if GlobalGatewaySSE.SSEC() && crypto.SSEC.IsRequested(r.Header) {
|
|
opts, err = getOpts(ctx, r, bucket, object)
|
|
opts.UserDefined = metadata
|
|
return
|
|
}
|
|
// default case of passing encryption headers and UserDefined metadata to backend
|
|
return getDefaultOpts(r.Header, false, metadata)
|
|
}
|
|
|
|
// get ObjectOptions for Copy calls with encryption headers provided on the target side and source side metadata
|
|
func copyDstOpts(ctx context.Context, r *http.Request, bucket, object string, metadata map[string]string) (opts ObjectOptions, err error) {
|
|
return putOpts(ctx, r, bucket, object, metadata)
|
|
}
|
|
|
|
// get ObjectOptions for Copy calls with encryption headers provided on the source side
|
|
func copySrcOpts(ctx context.Context, r *http.Request, bucket, object string) (ObjectOptions, error) {
|
|
var (
|
|
ssec encrypt.ServerSide
|
|
opts ObjectOptions
|
|
)
|
|
|
|
if GlobalGatewaySSE.SSEC() && crypto.SSECopy.IsRequested(r.Header) {
|
|
key, err := crypto.SSECopy.ParseHTTP(r.Header)
|
|
if err != nil {
|
|
return opts, err
|
|
}
|
|
derivedKey := deriveClientKey(key, bucket, object)
|
|
ssec, err = encrypt.NewSSEC(derivedKey[:])
|
|
if err != nil {
|
|
return opts, err
|
|
}
|
|
return ObjectOptions{ServerSideEncryption: encrypt.SSECopy(ssec)}, nil
|
|
}
|
|
|
|
// default case of passing encryption headers to backend
|
|
return getDefaultOpts(r.Header, true, nil)
|
|
}
|