frostfs-s3-gw/legacy/generic-handlers.go
2020-07-09 12:28:51 +03:00

822 lines
25 KiB
Go

/*
* MinIO Cloud Storage, (C) 2015-2020 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 legacy
import (
"net/http"
"strings"
"time"
"github.com/minio/minio-go/v6/pkg/set"
humanize "github.com/dustin/go-humanize"
"github.com/minio/minio/legacy/config/etcd/dns"
"github.com/minio/minio/legacy/crypto"
xhttp "github.com/minio/minio/legacy/http"
"github.com/minio/minio/legacy/http/stats"
"github.com/minio/minio/legacy/logger"
"github.com/minio/minio/pkg/handlers"
"github.com/minio/minio/pkg/wildcard"
"github.com/rs/cors"
)
// MiddlewareFunc - useful to chain different http.Handler middlewares
type MiddlewareFunc func(http.Handler) http.Handler
func registerMiddlewares(next http.Handler) http.Handler {
for _, handlerFn := range globalHandlers {
next = handlerFn(next)
}
return next
}
// Adds limiting body size middleware
// Maximum allowed form data field values. 64MiB is a guessed practical value
// which is more than enough to accommodate any form data fields and headers.
const requestFormDataSize = 64 * humanize.MiByte
// For any HTTP request, request body should be not more than 16GiB + requestFormDataSize
// where, 16GiB is the maximum allowed object size for object upload.
const requestMaxBodySize = globalMaxObjectSize + requestFormDataSize
type requestSizeLimitHandler struct {
handler http.Handler
maxBodySize int64
}
func setRequestSizeLimitHandler(h http.Handler) http.Handler {
return requestSizeLimitHandler{handler: h, maxBodySize: requestMaxBodySize}
}
func (h requestSizeLimitHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// Restricting read data to a given maximum length
r.Body = http.MaxBytesReader(w, r.Body, h.maxBodySize)
h.handler.ServeHTTP(w, r)
}
const (
// Maximum size for http headers - See: https://docs.aws.amazon.com/AmazonS3/latest/dev/UsingMetadata.html
maxHeaderSize = 8 * 1024
// Maximum size for user-defined metadata - See: https://docs.aws.amazon.com/AmazonS3/latest/dev/UsingMetadata.html
maxUserDataSize = 2 * 1024
)
type requestHeaderSizeLimitHandler struct {
http.Handler
}
func setRequestHeaderSizeLimitHandler(h http.Handler) http.Handler {
return requestHeaderSizeLimitHandler{h}
}
// ServeHTTP restricts the size of the http header to 8 KB and the size
// of the user-defined metadata to 2 KB.
func (h requestHeaderSizeLimitHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
if isHTTPHeaderSizeTooLarge(r.Header) {
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrMetadataTooLarge), r.URL, guessIsBrowserReq(r))
return
}
h.Handler.ServeHTTP(w, r)
}
// isHTTPHeaderSizeTooLarge returns true if the provided
// header is larger than 8 KB or the user-defined metadata
// is larger than 2 KB.
func isHTTPHeaderSizeTooLarge(header http.Header) bool {
var size, usersize int
for key := range header {
length := len(key) + len(header.Get(key))
size += length
for _, prefix := range userMetadataKeyPrefixes {
if HasPrefix(key, prefix) {
usersize += length
break
}
}
if usersize > maxUserDataSize || size > maxHeaderSize {
return true
}
}
return false
}
// ReservedMetadataPrefix is the prefix of a metadata key which
// is reserved and for internal use only.
const (
ReservedMetadataPrefix = "X-Minio-Internal-"
ReservedMetadataPrefixLower = "x-minio-internal-"
)
type reservedMetadataHandler struct {
http.Handler
}
func filterReservedMetadata(h http.Handler) http.Handler {
return reservedMetadataHandler{h}
}
// ServeHTTP fails if the request contains at least one reserved header which
// would be treated as metadata.
func (h reservedMetadataHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
if containsReservedMetadata(r.Header) {
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrUnsupportedMetadata), r.URL, guessIsBrowserReq(r))
return
}
h.Handler.ServeHTTP(w, r)
}
// containsReservedMetadata returns true if the http.Header contains
// keys which are treated as metadata but are reserved for internal use
// and must not set by clients
func containsReservedMetadata(header http.Header) bool {
for key := range header {
if strings.HasPrefix(strings.ToLower(key), ReservedMetadataPrefixLower) {
return true
}
}
return false
}
// Reserved bucket.
const (
minioReservedBucket = "minio"
minioReservedBucketPath = SlashSeparator + minioReservedBucket
loginPathPrefix = SlashSeparator + "login"
)
// Adds redirect rules for incoming requests.
type redirectHandler struct {
handler http.Handler
}
func setBrowserRedirectHandler(h http.Handler) http.Handler {
return redirectHandler{handler: h}
}
// Fetch redirect location if urlPath satisfies certain
// criteria. Some special names are considered to be
// redirectable, this is purely internal function and
// serves only limited purpose on redirect-handler for
// browser requests.
func getRedirectLocation(urlPath string) (rLocation string) {
if urlPath == minioReservedBucketPath {
rLocation = minioReservedBucketPath + SlashSeparator
}
if contains([]string{
SlashSeparator,
"/webrpc",
"/login",
"/favicon-16x16.png",
"/favicon-32x32.png",
"/favicon-96x96.png",
}, urlPath) {
rLocation = minioReservedBucketPath + urlPath
}
return rLocation
}
// guessIsBrowserReq - returns true if the request is browser.
// This implementation just validates user-agent and
// looks for "Mozilla" string. This is no way certifiable
// way to know if the request really came from a browser
// since User-Agent's can be arbitrary. But this is just
// a best effort function.
func guessIsBrowserReq(req *http.Request) bool {
if req == nil {
return false
}
aType := getRequestAuthType(req)
return strings.Contains(req.Header.Get("User-Agent"), "Mozilla") && globalBrowserEnabled &&
(aType == authTypeJWT || aType == authTypeAnonymous)
}
// guessIsHealthCheckReq - returns true if incoming request looks
// like healthcheck request
func guessIsHealthCheckReq(req *http.Request) bool {
if req == nil {
return false
}
aType := getRequestAuthType(req)
return aType == authTypeAnonymous && (req.Method == http.MethodGet || req.Method == http.MethodHead) &&
(req.URL.Path == healthCheckPathPrefix+healthCheckLivenessPath ||
req.URL.Path == healthCheckPathPrefix+healthCheckReadinessPath)
}
// guessIsMetricsReq - returns true if incoming request looks
// like metrics request
func guessIsMetricsReq(req *http.Request) bool {
if req == nil {
return false
}
aType := getRequestAuthType(req)
return (aType == authTypeAnonymous || aType == authTypeJWT) &&
req.URL.Path == minioReservedBucketPath+prometheusMetricsPath
}
// guessIsRPCReq - returns true if the request is for an RPC endpoint.
func guessIsRPCReq(req *http.Request) bool {
if req == nil {
return false
}
return req.Method == http.MethodPost &&
strings.HasPrefix(req.URL.Path, minioReservedBucketPath+SlashSeparator)
}
func (h redirectHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// Re-direction is handled specifically for browser requests.
if guessIsBrowserReq(r) {
// Fetch the redirect location if any.
redirectLocation := getRedirectLocation(r.URL.Path)
if redirectLocation != "" {
// Employ a temporary re-direct.
http.Redirect(w, r, redirectLocation, http.StatusTemporaryRedirect)
return
}
}
h.handler.ServeHTTP(w, r)
}
// Adds Cache-Control header
type cacheControlHandler struct {
handler http.Handler
}
func setBrowserCacheControlHandler(h http.Handler) http.Handler {
return cacheControlHandler{h}
}
func (h cacheControlHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
if r.Method == http.MethodGet && guessIsBrowserReq(r) {
// For all browser requests set appropriate Cache-Control policies
if HasPrefix(r.URL.Path, minioReservedBucketPath+SlashSeparator) {
if HasSuffix(r.URL.Path, ".js") || r.URL.Path == minioReservedBucketPath+"/favicon.ico" {
// For assets set cache expiry of one year. For each release, the name
// of the asset name will change and hence it can not be served from cache.
w.Header().Set(xhttp.CacheControl, "max-age=31536000")
} else {
// For non asset requests we serve index.html which will never be cached.
w.Header().Set(xhttp.CacheControl, "no-store")
}
}
}
h.handler.ServeHTTP(w, r)
}
// Check to allow access to the reserved "bucket" `/minio` for Admin
// API requests.
func isAdminReq(r *http.Request) bool {
return strings.HasPrefix(r.URL.Path, adminPathPrefix)
}
// guessIsLoginSTSReq - returns true if incoming request is Login STS user
func guessIsLoginSTSReq(req *http.Request) bool {
if req == nil {
return false
}
return strings.HasPrefix(req.URL.Path, loginPathPrefix) ||
(req.Method == http.MethodPost && req.URL.Path == SlashSeparator &&
getRequestAuthType(req) == authTypeSTS)
}
// Adds verification for incoming paths.
type minioReservedBucketHandler struct {
handler http.Handler
}
func setReservedBucketHandler(h http.Handler) http.Handler {
return minioReservedBucketHandler{h}
}
func (h minioReservedBucketHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
switch {
case guessIsRPCReq(r), guessIsBrowserReq(r), guessIsHealthCheckReq(r), guessIsMetricsReq(r), isAdminReq(r):
// Allow access to reserved buckets
default:
// For all other requests reject access to reserved buckets
bucketName, _ := request2BucketObjectName(r)
if isMinioReservedBucket(bucketName) || isMinioMetaBucket(bucketName) {
browser := guessIsBrowserReq(r)
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrAllAccessDisabled), r.URL, browser)
return
}
}
h.handler.ServeHTTP(w, r)
}
type timeValidityHandler struct {
handler http.Handler
}
// setTimeValidityHandler to validate parsable time over http header
func setTimeValidityHandler(h http.Handler) http.Handler {
return timeValidityHandler{h}
}
// Supported Amz date formats.
var amzDateFormats = []string{
time.RFC1123,
time.RFC1123Z,
iso8601Format,
// Add new AMZ date formats here.
}
// Supported Amz date headers.
var amzDateHeaders = []string{
"x-amz-date",
"date",
}
// parseAmzDate - parses date string into supported amz date formats.
func parseAmzDate(amzDateStr string) (amzDate time.Time, apiErr APIErrorCode) {
for _, dateFormat := range amzDateFormats {
amzDate, err := time.Parse(dateFormat, amzDateStr)
if err == nil {
return amzDate, ErrNone
}
}
return time.Time{}, ErrMalformedDate
}
// parseAmzDateHeader - parses supported amz date headers, in
// supported amz date formats.
func parseAmzDateHeader(req *http.Request) (time.Time, APIErrorCode) {
for _, amzDateHeader := range amzDateHeaders {
amzDateStr := req.Header.Get(amzDateHeader)
if amzDateStr != "" {
return parseAmzDate(amzDateStr)
}
}
// Date header missing.
return time.Time{}, ErrMissingDateHeader
}
func (h timeValidityHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
aType := getRequestAuthType(r)
if aType == authTypeSigned || aType == authTypeSignedV2 || aType == authTypeStreamingSigned {
// Verify if date headers are set, if not reject the request
amzDate, errCode := parseAmzDateHeader(r)
if errCode != ErrNone {
// All our internal APIs are sensitive towards Date
// header, for all requests where Date header is not
// present we will reject such clients.
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(errCode), r.URL, guessIsBrowserReq(r))
return
}
// Verify if the request date header is shifted by less than globalMaxSkewTime parameter in the past
// or in the future, reject request otherwise.
curTime := UTCNow()
if curTime.Sub(amzDate) > globalMaxSkewTime || amzDate.Sub(curTime) > globalMaxSkewTime {
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrRequestTimeTooSkewed), r.URL, guessIsBrowserReq(r))
return
}
}
h.handler.ServeHTTP(w, r)
}
type resourceHandler struct {
handler http.Handler
}
// setCorsHandler handler for CORS (Cross Origin Resource Sharing)
func setCorsHandler(h http.Handler) http.Handler {
commonS3Headers := []string{
xhttp.Date,
xhttp.ETag,
xhttp.ServerInfo,
xhttp.Connection,
xhttp.AcceptRanges,
xhttp.ContentRange,
xhttp.ContentEncoding,
xhttp.ContentLength,
xhttp.ContentType,
"X-Amz*",
"x-amz*",
"*",
}
c := cors.New(cors.Options{
AllowOriginFunc: func(origin string) bool {
for _, allowedOrigin := range globalAPIConfig.getCorsAllowOrigins() {
if wildcard.MatchSimple(allowedOrigin, origin) {
return true
}
}
return false
},
AllowedMethods: []string{
http.MethodGet,
http.MethodPut,
http.MethodHead,
http.MethodPost,
http.MethodDelete,
http.MethodOptions,
http.MethodPatch,
},
AllowedHeaders: commonS3Headers,
ExposedHeaders: commonS3Headers,
AllowCredentials: true,
})
return c.Handler(h)
}
// setIgnoreResourcesHandler -
// Ignore resources handler is wrapper handler used for API request resource validation
// Since we do not support all the S3 queries, it is necessary for us to throw back a
// valid error message indicating that requested feature is not implemented.
func setIgnoreResourcesHandler(h http.Handler) http.Handler {
return resourceHandler{h}
}
// Checks requests for not implemented Bucket resources
func ignoreNotImplementedBucketResources(req *http.Request) bool {
for name := range req.URL.Query() {
// Enable PutBucketACL, GetBucketACL, GetBucketCors,
// GetBucketWebsite, GetBucketAcccelerate,
// GetBucketRequestPayment, GetBucketLogging,
// GetBucketLifecycle, GetBucketReplication,
// GetBucketTagging, GetBucketVersioning,
// DeleteBucketTagging, and DeleteBucketWebsite
// dummy calls specifically.
if name == "acl" && req.Method == http.MethodPut {
return false
}
if ((name == "acl" ||
name == "cors" ||
name == "website" ||
name == "accelerate" ||
name == "requestPayment" ||
name == "logging" ||
name == "lifecycle" ||
name == "replication" ||
name == "tagging" ||
name == "versioning") && req.Method == http.MethodGet) ||
((name == "tagging" ||
name == "website") && req.Method == http.MethodDelete) {
return false
}
if notImplementedBucketResourceNames[name] {
return true
}
}
return false
}
// Checks requests for not implemented Object resources
func ignoreNotImplementedObjectResources(req *http.Request) bool {
for name := range req.URL.Query() {
// Enable Get/PutObjectACL dummy call specifically.
if name == "acl" && (req.Method == http.MethodGet || req.Method == http.MethodPut) {
return false
}
if notImplementedObjectResourceNames[name] {
return true
}
}
return false
}
// List of not implemented bucket queries
var notImplementedBucketResourceNames = map[string]bool{
"accelerate": true,
"cors": true,
"inventory": true,
"logging": true,
"metrics": true,
"replication": true,
"requestPayment": true,
"versioning": true,
"website": true,
}
// List of not implemented object queries
var notImplementedObjectResourceNames = map[string]bool{
"restore": true,
"torrent": true,
}
// Resource handler ServeHTTP() wrapper
func (h resourceHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
bucketName, objectName := request2BucketObjectName(r)
// If bucketName is present and not objectName check for bucket level resource queries.
if bucketName != "" && objectName == "" {
if ignoreNotImplementedBucketResources(r) {
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrNotImplemented), r.URL, guessIsBrowserReq(r))
return
}
}
// If bucketName and objectName are present check for its resource queries.
if bucketName != "" && objectName != "" {
if ignoreNotImplementedObjectResources(r) {
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrNotImplemented), r.URL, guessIsBrowserReq(r))
return
}
}
// Serve HTTP.
h.handler.ServeHTTP(w, r)
}
// httpStatsHandler definition: gather HTTP statistics
type httpStatsHandler struct {
handler http.Handler
}
// setHttpStatsHandler sets a http Stats Handler
func setHTTPStatsHandler(h http.Handler) http.Handler {
return httpStatsHandler{handler: h}
}
func (h httpStatsHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// Meters s3 connection stats.
meteredRequest := &stats.IncomingTrafficMeter{ReadCloser: r.Body}
meteredResponse := &stats.OutgoingTrafficMeter{ResponseWriter: w}
// Execute the request
r.Body = meteredRequest
h.handler.ServeHTTP(meteredResponse, r)
if strings.HasPrefix(r.URL.Path, minioReservedBucketPath) {
globalConnStats.incInputBytes(meteredRequest.BytesCount())
globalConnStats.incOutputBytes(meteredResponse.BytesCount())
} else {
globalConnStats.incS3InputBytes(meteredRequest.BytesCount())
globalConnStats.incS3OutputBytes(meteredResponse.BytesCount())
}
}
// requestValidityHandler validates all the incoming paths for
// any malicious requests.
type requestValidityHandler struct {
handler http.Handler
}
func setRequestValidityHandler(h http.Handler) http.Handler {
return requestValidityHandler{handler: h}
}
// Bad path components to be rejected by the path validity handler.
const (
dotdotComponent = ".."
dotComponent = "."
)
// Check if the incoming path has bad path components,
// such as ".." and "."
func hasBadPathComponent(path string) bool {
path = strings.TrimSpace(path)
for _, p := range strings.Split(path, SlashSeparator) {
switch strings.TrimSpace(p) {
case dotdotComponent:
return true
case dotComponent:
return true
}
}
return false
}
// Check if client is sending a malicious request.
func hasMultipleAuth(r *http.Request) bool {
authTypeCount := 0
for _, hasValidAuth := range []func(*http.Request) bool{isRequestSignatureV2, isRequestPresignedSignatureV2, isRequestSignatureV4, isRequestPresignedSignatureV4, isRequestJWT, isRequestPostPolicySignatureV4} {
if hasValidAuth(r) {
authTypeCount++
}
}
return authTypeCount > 1
}
func (h requestValidityHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// Check for bad components in URL path.
if hasBadPathComponent(r.URL.Path) {
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrInvalidResourceName), r.URL, guessIsBrowserReq(r))
return
}
// Check for bad components in URL query values.
for _, vv := range r.URL.Query() {
for _, v := range vv {
if hasBadPathComponent(v) {
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrInvalidResourceName), r.URL, guessIsBrowserReq(r))
return
}
}
}
if hasMultipleAuth(r) {
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrInvalidRequest), r.URL, guessIsBrowserReq(r))
return
}
h.handler.ServeHTTP(w, r)
}
// To forward the path style requests on a bucket to the right
// configured server, bucket to IP configuration is obtained
// from centralized etcd configuration service.
type bucketForwardingHandler struct {
fwd *handlers.Forwarder
handler http.Handler
}
func (f bucketForwardingHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
if globalDNSConfig == nil || len(globalDomainNames) == 0 ||
guessIsHealthCheckReq(r) || guessIsMetricsReq(r) ||
guessIsRPCReq(r) || guessIsLoginSTSReq(r) || isAdminReq(r) ||
!globalBucketFederation {
f.handler.ServeHTTP(w, r)
return
}
// For browser requests, when federation is setup we need to
// specifically handle download and upload for browser requests.
if guessIsBrowserReq(r) && globalDNSConfig != nil && len(globalDomainNames) > 0 {
var bucket, _ string
switch r.Method {
case http.MethodPut:
if getRequestAuthType(r) == authTypeJWT {
bucket, _ = path2BucketObjectWithBasePath(minioReservedBucketPath+"/upload", r.URL.Path)
}
case http.MethodGet:
if t := r.URL.Query().Get("token"); t != "" {
bucket, _ = path2BucketObjectWithBasePath(minioReservedBucketPath+"/download", r.URL.Path)
} else if getRequestAuthType(r) != authTypeJWT && !strings.HasPrefix(r.URL.Path, minioReservedBucketPath) {
bucket, _ = request2BucketObjectName(r)
}
}
if bucket == "" {
f.handler.ServeHTTP(w, r)
return
}
sr, err := globalDNSConfig.Get(bucket)
if err != nil {
if err == dns.ErrNoEntriesFound {
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrNoSuchBucket),
r.URL, guessIsBrowserReq(r))
} else {
writeErrorResponse(r.Context(), w, toAPIError(r.Context(), err),
r.URL, guessIsBrowserReq(r))
}
return
}
if globalDomainIPs.Intersection(set.CreateStringSet(getHostsSlice(sr)...)).IsEmpty() {
r.URL.Scheme = "http"
if globalIsSSL {
r.URL.Scheme = "https"
}
r.URL.Host = getHostFromSrv(sr)
f.fwd.ServeHTTP(w, r)
return
}
f.handler.ServeHTTP(w, r)
return
}
bucket, object := request2BucketObjectName(r)
// Requests in federated setups for STS type calls which are
// performed at '/' resource should be routed by the muxer,
// the assumption is simply such that requests without a bucket
// in a federated setup cannot be proxied, so serve them at
// current server.
if bucket == "" {
f.handler.ServeHTTP(w, r)
return
}
// MakeBucket requests should be handled at current endpoint
if r.Method == http.MethodPut && bucket != "" && object == "" {
f.handler.ServeHTTP(w, r)
return
}
// CopyObject requests should be handled at current endpoint as path style
// requests have target bucket and object in URI and source details are in
// header fields
if r.Method == http.MethodPut && r.Header.Get(xhttp.AmzCopySource) != "" {
bucket, object = path2BucketObject(r.Header.Get(xhttp.AmzCopySource))
if bucket == "" || object == "" {
f.handler.ServeHTTP(w, r)
return
}
}
sr, err := globalDNSConfig.Get(bucket)
if err != nil {
if err == dns.ErrNoEntriesFound {
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrNoSuchBucket), r.URL, guessIsBrowserReq(r))
} else {
writeErrorResponse(r.Context(), w, toAPIError(r.Context(), err), r.URL, guessIsBrowserReq(r))
}
return
}
if globalDomainIPs.Intersection(set.CreateStringSet(getHostsSlice(sr)...)).IsEmpty() {
r.URL.Scheme = "http"
if globalIsSSL {
r.URL.Scheme = "https"
}
r.URL.Host = getHostFromSrv(sr)
f.fwd.ServeHTTP(w, r)
return
}
f.handler.ServeHTTP(w, r)
}
// setBucketForwardingHandler middleware forwards the path style requests
// on a bucket to the right bucket location, bucket to IP configuration
// is obtained from centralized etcd configuration service.
func setBucketForwardingHandler(h http.Handler) http.Handler {
fwd := handlers.NewForwarder(&handlers.Forwarder{
PassHost: true,
RoundTripper: NewGatewayHTTPTransport(),
Logger: func(err error) {
logger.LogIf(GlobalContext, err)
},
})
return bucketForwardingHandler{fwd, h}
}
// customHeaderHandler sets x-amz-request-id header.
// Previously, this value was set right before a response was sent to
// the client. So, logger and Error response XML were not using this
// value. This is set here so that this header can be logged as
// part of the log entry, Error response XML and auditing.
type customHeaderHandler struct {
handler http.Handler
}
func addCustomHeaders(h http.Handler) http.Handler {
return customHeaderHandler{handler: h}
}
func (s customHeaderHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// Set custom headers such as x-amz-request-id for each request.
w.Header().Set(xhttp.AmzRequestID, mustGetRequestID(UTCNow()))
s.handler.ServeHTTP(logger.NewResponseWriter(w), r)
}
type securityHeaderHandler struct {
handler http.Handler
}
func addSecurityHeaders(h http.Handler) http.Handler {
return securityHeaderHandler{handler: h}
}
func (s securityHeaderHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
header := w.Header()
header.Set("X-XSS-Protection", "1; mode=block") // Prevents against XSS attacks
header.Set("Content-Security-Policy", "block-all-mixed-content") // prevent mixed (HTTP / HTTPS content)
s.handler.ServeHTTP(w, r)
}
// criticalErrorHandler handles critical server failures caused by
// `panic(logger.ErrCritical)` as done by `logger.CriticalIf`.
//
// It should be always the first / highest HTTP handler.
type criticalErrorHandler struct{ handler http.Handler }
func (h criticalErrorHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
defer func() {
if err := recover(); err == logger.ErrCritical { // handle
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrInternalError), r.URL, guessIsBrowserReq(r))
return
} else if err != nil {
panic(err) // forward other panic calls
}
}()
h.handler.ServeHTTP(w, r)
}
func setSSETLSHandler(h http.Handler) http.Handler { return sseTLSHandler{h} }
// sseTLSHandler enforces certain rules for SSE requests which are made / must be made over TLS.
type sseTLSHandler struct{ handler http.Handler }
func (h sseTLSHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// Deny SSE-C requests if not made over TLS
if !globalIsSSL && (crypto.SSEC.IsRequested(r.Header) || crypto.SSECopy.IsRequested(r.Header)) {
if r.Method == http.MethodHead {
writeErrorResponseHeadersOnly(w, errorCodes.ToAPIErr(ErrInsecureSSECustomerRequest))
} else {
writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrInsecureSSECustomerRequest), r.URL, guessIsBrowserReq(r))
}
return
}
h.handler.ServeHTTP(w, r)
}