minio/internal/crypto/header.go

87 lines
2.9 KiB
Go

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package crypto
import (
"bytes"
"crypto/md5"
"encoding/base64"
"net/http"
xhttp "github.com/minio/minio/internal/http"
)
// 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(xhttp.AmzServerSideEncryptionCustomerKey)
h.Del(xhttp.AmzServerSideEncryptionCopyCustomerKey)
h.Del(xhttp.AmzMetaUnencryptedContentLength)
h.Del(xhttp.AmzMetaUnencryptedContentMD5)
}
var (
// SSECopy represents AWS SSE-C for copy requests. It provides
// functionality to handle SSE-C copy requests.
SSECopy = ssecCopy{}
)
type ssecCopy struct{}
// 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[xhttp.AmzServerSideEncryptionCopyCustomerAlgorithm]; ok {
return true
}
if _, ok := h[xhttp.AmzServerSideEncryptionCopyCustomerKey]; ok {
return true
}
if _, ok := h[xhttp.AmzServerSideEncryptionCopyCustomerKeyMD5]; ok {
return true
}
return false
}
// 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(xhttp.AmzServerSideEncryptionCopyCustomerAlgorithm) != xhttp.AmzEncryptionAES {
return key, ErrInvalidCustomerAlgorithm
}
if h.Get(xhttp.AmzServerSideEncryptionCopyCustomerKey) == "" {
return key, ErrMissingCustomerKey
}
if h.Get(xhttp.AmzServerSideEncryptionCopyCustomerKeyMD5) == "" {
return key, ErrMissingCustomerKeyMD5
}
clientKey, err := base64.StdEncoding.DecodeString(h.Get(xhttp.AmzServerSideEncryptionCopyCustomerKey))
if err != nil || len(clientKey) != 32 { // The client key must be 256 bits long
return key, ErrInvalidCustomerKey
}
keyMD5, err := base64.StdEncoding.DecodeString(h.Get(xhttp.AmzServerSideEncryptionCopyCustomerKeyMD5))
if md5Sum := md5.Sum(clientKey); err != nil || !bytes.Equal(md5Sum[:], keyMD5) {
return key, ErrCustomerKeyMD5Mismatch
}
copy(key[:], clientKey)
return key, nil
}