220 lines
6.6 KiB
Go
220 lines
6.6 KiB
Go
// Minio Cloud Storage, (C) 2015, 2016, 2017, 2018 Minio, Inc.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package crypto
|
|
|
|
import (
|
|
"bytes"
|
|
"crypto/md5"
|
|
"encoding/base64"
|
|
"net/http"
|
|
"strings"
|
|
)
|
|
|
|
// SSEHeader is the general AWS SSE HTTP header key.
|
|
const SSEHeader = "X-Amz-Server-Side-Encryption"
|
|
|
|
const (
|
|
// SSEKmsID is the HTTP header key referencing the SSE-KMS
|
|
// key ID.
|
|
SSEKmsID = SSEHeader + "-Aws-Kms-Key-Id"
|
|
|
|
// SSEKmsContext is the HTTP header key referencing the
|
|
// SSE-KMS encryption context.
|
|
SSEKmsContext = SSEHeader + "-Context"
|
|
)
|
|
|
|
const (
|
|
// SSECAlgorithm is the HTTP header key referencing
|
|
// the SSE-C algorithm.
|
|
SSECAlgorithm = SSEHeader + "-Customer-Algorithm"
|
|
|
|
// SSECKey is the HTTP header key referencing the
|
|
// SSE-C client-provided key..
|
|
SSECKey = SSEHeader + "-Customer-Key"
|
|
|
|
// SSECKeyMD5 is the HTTP header key referencing
|
|
// the MD5 sum of the client-provided key.
|
|
SSECKeyMD5 = SSEHeader + "-Customer-Key-Md5"
|
|
)
|
|
|
|
const (
|
|
// SSECopyAlgorithm is the HTTP header key referencing
|
|
// the SSE-C algorithm for SSE-C copy requests.
|
|
SSECopyAlgorithm = "X-Amz-Copy-Source-Server-Side-Encryption-Customer-Algorithm"
|
|
|
|
// SSECopyKey is the HTTP header key referencing the SSE-C
|
|
// client-provided key for SSE-C copy requests.
|
|
SSECopyKey = "X-Amz-Copy-Source-Server-Side-Encryption-Customer-Key"
|
|
|
|
// SSECopyKeyMD5 is the HTTP header key referencing the
|
|
// MD5 sum of the client key for SSE-C copy requests.
|
|
SSECopyKeyMD5 = "X-Amz-Copy-Source-Server-Side-Encryption-Customer-Key-Md5"
|
|
)
|
|
|
|
const (
|
|
// SSEAlgorithmAES256 is the only supported value for the SSE-S3 or SSE-C algorithm header.
|
|
// For SSE-S3 see: https://docs.aws.amazon.com/AmazonS3/latest/dev/SSEUsingRESTAPI.html
|
|
// For SSE-C see: https://docs.aws.amazon.com/AmazonS3/latest/dev/ServerSideEncryptionCustomerKeys.html
|
|
SSEAlgorithmAES256 = "AES256"
|
|
|
|
// SSEAlgorithmKMS is the value of 'X-Amz-Server-Side-Encryption' for SSE-KMS.
|
|
// See: https://docs.aws.amazon.com/AmazonS3/latest/dev/UsingKMSEncryption.html
|
|
SSEAlgorithmKMS = "aws:kms"
|
|
)
|
|
|
|
// RemoveSensitiveHeaders removes confidential encryption
|
|
// information - e.g. the SSE-C key - from the HTTP headers.
|
|
// It has the same semantics as RemoveSensitiveEntires.
|
|
func RemoveSensitiveHeaders(h http.Header) {
|
|
h.Del(SSECKey)
|
|
h.Del(SSECopyKey)
|
|
}
|
|
|
|
// S3 represents AWS SSE-S3. It provides functionality to handle
|
|
// SSE-S3 requests.
|
|
var S3 = s3{}
|
|
|
|
type s3 struct{}
|
|
|
|
// IsRequested returns true if the HTTP headers indicates that
|
|
// the S3 client requests SSE-S3.
|
|
func (s3) IsRequested(h http.Header) bool {
|
|
_, ok := h[SSEHeader]
|
|
return ok && strings.ToLower(h.Get(SSEHeader)) != SSEAlgorithmKMS // Return only true if the SSE header is specified and does not contain the SSE-KMS value
|
|
}
|
|
|
|
// ParseHTTP parses the SSE-S3 related HTTP headers and checks
|
|
// whether they contain valid values.
|
|
func (s3) ParseHTTP(h http.Header) (err error) {
|
|
if h.Get(SSEHeader) != SSEAlgorithmAES256 {
|
|
err = ErrInvalidEncryptionMethod
|
|
}
|
|
return
|
|
}
|
|
|
|
// S3KMS represents AWS SSE-KMS. It provides functionality to
|
|
// handle SSE-KMS requests.
|
|
var S3KMS = s3KMS{}
|
|
|
|
type s3KMS struct{}
|
|
|
|
// IsRequested returns true if the HTTP headers indicates that
|
|
// the S3 client requests SSE-KMS.
|
|
func (s3KMS) IsRequested(h http.Header) bool {
|
|
if _, ok := h[SSEKmsID]; ok {
|
|
return true
|
|
}
|
|
if _, ok := h[SSEKmsContext]; ok {
|
|
return true
|
|
}
|
|
if _, ok := h[SSEHeader]; ok {
|
|
return strings.ToUpper(h.Get(SSEHeader)) != SSEAlgorithmAES256 // Return only true if the SSE header is specified and does not contain the SSE-S3 value
|
|
}
|
|
return false
|
|
}
|
|
|
|
var (
|
|
// SSEC represents AWS SSE-C. It provides functionality to handle
|
|
// SSE-C requests.
|
|
SSEC = ssec{}
|
|
|
|
// SSECopy represents AWS SSE-C for copy requests. It provides
|
|
// functionality to handle SSE-C copy requests.
|
|
SSECopy = ssecCopy{}
|
|
)
|
|
|
|
type ssec struct{}
|
|
type ssecCopy struct{}
|
|
|
|
// IsRequested returns true if the HTTP headers contains
|
|
// at least one SSE-C header. SSE-C copy headers are ignored.
|
|
func (ssec) IsRequested(h http.Header) bool {
|
|
if _, ok := h[SSECAlgorithm]; ok {
|
|
return true
|
|
}
|
|
if _, ok := h[SSECKey]; ok {
|
|
return true
|
|
}
|
|
if _, ok := h[SSECKeyMD5]; ok {
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
// IsRequested returns true if the HTTP headers contains
|
|
// at least one SSE-C copy header. Regular SSE-C headers
|
|
// are ignored.
|
|
func (ssecCopy) IsRequested(h http.Header) bool {
|
|
if _, ok := h[SSECopyAlgorithm]; ok {
|
|
return true
|
|
}
|
|
if _, ok := h[SSECopyKey]; ok {
|
|
return true
|
|
}
|
|
if _, ok := h[SSECopyKeyMD5]; ok {
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
// ParseHTTP parses the SSE-C headers and returns the SSE-C client key
|
|
// on success. SSE-C copy headers are ignored.
|
|
func (ssec) ParseHTTP(h http.Header) (key [32]byte, err error) {
|
|
if h.Get(SSECAlgorithm) != SSEAlgorithmAES256 {
|
|
return key, ErrInvalidCustomerAlgorithm
|
|
}
|
|
if h.Get(SSECKey) == "" {
|
|
return key, ErrMissingCustomerKey
|
|
}
|
|
if h.Get(SSECKeyMD5) == "" {
|
|
return key, ErrMissingCustomerKeyMD5
|
|
}
|
|
|
|
clientKey, err := base64.StdEncoding.DecodeString(h.Get(SSECKey))
|
|
if err != nil || len(clientKey) != 32 { // The client key must be 256 bits long
|
|
return key, ErrInvalidCustomerKey
|
|
}
|
|
keyMD5, err := base64.StdEncoding.DecodeString(h.Get(SSECKeyMD5))
|
|
if md5Sum := md5.Sum(clientKey); err != nil || !bytes.Equal(md5Sum[:], keyMD5) {
|
|
return key, ErrCustomerKeyMD5Mismatch
|
|
}
|
|
copy(key[:], clientKey)
|
|
return key, nil
|
|
}
|
|
|
|
// ParseHTTP parses the SSE-C copy headers and returns the SSE-C client key
|
|
// on success. Regular SSE-C headers are ignored.
|
|
func (ssecCopy) ParseHTTP(h http.Header) (key [32]byte, err error) {
|
|
if h.Get(SSECopyAlgorithm) != SSEAlgorithmAES256 {
|
|
return key, ErrInvalidCustomerAlgorithm
|
|
}
|
|
if h.Get(SSECopyKey) == "" {
|
|
return key, ErrMissingCustomerKey
|
|
}
|
|
if h.Get(SSECopyKeyMD5) == "" {
|
|
return key, ErrMissingCustomerKeyMD5
|
|
}
|
|
|
|
clientKey, err := base64.StdEncoding.DecodeString(h.Get(SSECopyKey))
|
|
if err != nil || len(clientKey) != 32 { // The client key must be 256 bits long
|
|
return key, ErrInvalidCustomerKey
|
|
}
|
|
keyMD5, err := base64.StdEncoding.DecodeString(h.Get(SSECopyKeyMD5))
|
|
if md5Sum := md5.Sum(clientKey); err != nil || !bytes.Equal(md5Sum[:], keyMD5) {
|
|
return key, ErrCustomerKeyMD5Mismatch
|
|
}
|
|
copy(key[:], clientKey)
|
|
return key, nil
|
|
}
|