minio/cmd/api-headers.go

199 lines
5.8 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 cmd
import (
"bytes"
"encoding/json"
"encoding/xml"
"fmt"
"net/http"
"net/url"
"strconv"
"strings"
"time"
"github.com/minio/minio/internal/crypto"
xhttp "github.com/minio/minio/internal/http"
)
// Returns a hexadecimal representation of time at the
// time response is sent to the client.
func mustGetRequestID(t time.Time) string {
return fmt.Sprintf("%X", t.UnixNano())
}
// setEventStreamHeaders to allow proxies to avoid buffering proxy responses
func setEventStreamHeaders(w http.ResponseWriter) {
w.Header().Set(xhttp.ContentType, "text/event-stream")
w.Header().Set(xhttp.CacheControl, "no-cache") // nginx to turn off buffering
w.Header().Set("X-Accel-Buffering", "no") // nginx to turn off buffering
}
// Write http common headers
func setCommonHeaders(w http.ResponseWriter) {
// Set the "Server" http header.
w.Header().Set(xhttp.ServerInfo, "MinIO")
// Set `x-amz-bucket-region` only if region is set on the server
// by default minio uses an empty region.
if region := globalServerRegion; region != "" {
w.Header().Set(xhttp.AmzBucketRegion, region)
}
w.Header().Set(xhttp.AcceptRanges, "bytes")
// Remove sensitive information
crypto.RemoveSensitiveHeaders(w.Header())
}
// Encodes the response headers into XML format.
func encodeResponse(response interface{}) []byte {
var bytesBuffer bytes.Buffer
bytesBuffer.WriteString(xml.Header)
e := xml.NewEncoder(&bytesBuffer)
e.Encode(response)
return bytesBuffer.Bytes()
}
// Encodes the response headers into JSON format.
func encodeResponseJSON(response interface{}) []byte {
var bytesBuffer bytes.Buffer
e := json.NewEncoder(&bytesBuffer)
e.Encode(response)
return bytesBuffer.Bytes()
}
// Write parts count
func setPartsCountHeaders(w http.ResponseWriter, objInfo ObjectInfo) {
if strings.Contains(objInfo.ETag, "-") && len(objInfo.Parts) > 0 {
w.Header()[xhttp.AmzMpPartsCount] = []string{strconv.Itoa(len(objInfo.Parts))}
}
}
// Write object header
func setObjectHeaders(w http.ResponseWriter, objInfo ObjectInfo, rs *HTTPRangeSpec, opts ObjectOptions) (err error) {
// set common headers
setCommonHeaders(w)
// Set last modified time.
lastModified := objInfo.ModTime.UTC().Format(http.TimeFormat)
w.Header().Set(xhttp.LastModified, lastModified)
// Set Etag if available.
if objInfo.ETag != "" {
w.Header()[xhttp.ETag] = []string{"\"" + objInfo.ETag + "\""}
}
if objInfo.ContentType != "" {
w.Header().Set(xhttp.ContentType, objInfo.ContentType)
}
if objInfo.ContentEncoding != "" {
w.Header().Set(xhttp.ContentEncoding, objInfo.ContentEncoding)
}
if !objInfo.Expires.IsZero() {
w.Header().Set(xhttp.Expires, objInfo.Expires.UTC().Format(http.TimeFormat))
}
if globalCacheConfig.Enabled {
w.Header().Set(xhttp.XCache, objInfo.CacheStatus.String())
w.Header().Set(xhttp.XCacheLookup, objInfo.CacheLookupStatus.String())
}
// Set tag count if object has tags
if len(objInfo.UserTags) > 0 {
tags, _ := url.ParseQuery(objInfo.UserTags)
if len(tags) > 0 {
w.Header()[xhttp.AmzTagCount] = []string{strconv.Itoa(len(tags))}
}
}
// Set all other user defined metadata.
for k, v := range objInfo.UserDefined {
if strings.HasPrefix(strings.ToLower(k), ReservedMetadataPrefixLower) {
// Do not need to send any internal metadata
// values to client.
continue
}
// https://github.com/google/security-research/security/advisories/GHSA-76wf-9vgp-pj7w
if equals(k, xhttp.AmzMetaUnencryptedContentLength, xhttp.AmzMetaUnencryptedContentMD5) {
continue
}
var isSet bool
for _, userMetadataPrefix := range userMetadataKeyPrefixes {
if !strings.HasPrefix(strings.ToLower(k), strings.ToLower(userMetadataPrefix)) {
continue
}
w.Header()[strings.ToLower(k)] = []string{v}
isSet = true
break
}
if !isSet {
w.Header().Set(k, v)
}
}
var start, rangeLen int64
totalObjectSize, err := objInfo.GetActualSize()
if err != nil {
return err
}
if rs == nil && opts.PartNumber > 0 {
rs = partNumberToRangeSpec(objInfo, opts.PartNumber)
}
// For providing ranged content
start, rangeLen, err = rs.GetOffsetLength(totalObjectSize)
if err != nil {
return err
}
// Set content length.
w.Header().Set(xhttp.ContentLength, strconv.FormatInt(rangeLen, 10))
if rs != nil {
contentRange := fmt.Sprintf("bytes %d-%d/%d", start, start+rangeLen-1, totalObjectSize)
w.Header().Set(xhttp.ContentRange, contentRange)
}
// Set the relevant version ID as part of the response header.
if objInfo.VersionID != "" {
w.Header()[xhttp.AmzVersionID] = []string{objInfo.VersionID}
}
if objInfo.ReplicationStatus.String() != "" {
w.Header()[xhttp.AmzBucketReplicationStatus] = []string{objInfo.ReplicationStatus.String()}
}
if objInfo.IsRemote() {
// Check if object is being restored. For more information on x-amz-restore header see
// https://docs.aws.amazon.com/AmazonS3/latest/API/API_HeadObject.html#API_HeadObject_ResponseSyntax
w.Header()[xhttp.AmzStorageClass] = []string{objInfo.TransitionTier}
}
if lc, err := globalLifecycleSys.Get(objInfo.Bucket); err == nil {
lc.SetPredictionHeaders(w, objInfo.ToLifecycleOpts())
}
return nil
}