minio/cmd/handler-utils.go
Harshavardhana 3fe33e7b15 handler: simplify parsing valid location constraint. (#4040)
Separate out validating v/s parsing logic in
isValidLocationConstraint() into parseLocationConstraint()
and isValidLocation()

Additionally also set `X-Amz-Bucket-Region` as part of the
common headers for the clients to fallback on in-case of any
region related errors.
2017-04-03 14:50:09 -07:00

239 lines
7.1 KiB
Go

/*
* Minio Cloud Storage, (C) 2015, 2016, 2017 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 cmd
import (
"io"
"mime/multipart"
"net/http"
"net/url"
"strings"
)
// Parses location constraint from the incoming reader.
func parseLocationConstraint(r *http.Request) (location string, s3Error APIErrorCode) {
// If the request has no body with content-length set to 0,
// we do not have to validate location constraint. Bucket will
// be created at default region.
locationConstraint := createBucketLocationConfiguration{}
err := xmlDecoder(r.Body, &locationConstraint, r.ContentLength)
if err != nil && err != io.EOF {
errorIf(err, "Unable to xml decode location constraint")
// Treat all other failures as XML parsing errors.
return "", ErrMalformedXML
} // else for both err as nil or io.EOF
location = locationConstraint.Location
if location == "" {
location = globalMinioDefaultRegion
}
return location, ErrNone
}
// Validates input location is same as configured region
// of Minio server.
func isValidLocation(location string) bool {
return serverConfig.GetRegion() == location
}
// Supported headers that needs to be extracted.
var supportedHeaders = []string{
"content-type",
"cache-control",
"content-encoding",
"content-disposition",
// Add more supported headers here.
}
// isMetadataDirectiveValid - check if metadata-directive is valid.
func isMetadataDirectiveValid(h http.Header) bool {
_, ok := h[http.CanonicalHeaderKey("X-Amz-Metadata-Directive")]
if ok {
// Check atleast set metadata-directive is valid.
return (isMetadataCopy(h) || isMetadataReplace(h))
}
// By default if x-amz-metadata-directive is not we
// treat it as 'COPY' this function returns true.
return true
}
// Check if the metadata COPY is requested.
func isMetadataCopy(h http.Header) bool {
return h.Get("X-Amz-Metadata-Directive") == "COPY"
}
// Check if the metadata REPLACE is requested.
func isMetadataReplace(h http.Header) bool {
return h.Get("X-Amz-Metadata-Directive") == "REPLACE"
}
// Splits an incoming path into bucket and object components.
func path2BucketAndObject(path string) (bucket, object string) {
// Skip the first element if it is '/', split the rest.
path = strings.TrimPrefix(path, "/")
pathComponents := strings.SplitN(path, "/", 2)
// Save the bucket and object extracted from path.
switch len(pathComponents) {
case 1:
bucket = pathComponents[0]
case 2:
bucket = pathComponents[0]
object = pathComponents[1]
}
return bucket, object
}
// extractMetadataFromHeader extracts metadata from HTTP header.
func extractMetadataFromHeader(header http.Header) map[string]string {
if header == nil {
return nil
}
metadata := make(map[string]string)
// Save standard supported headers.
for _, supportedHeader := range supportedHeaders {
canonicalHeader := http.CanonicalHeaderKey(supportedHeader)
// HTTP headers are case insensitive, look for both canonical
// and non canonical entries.
if _, ok := header[canonicalHeader]; ok {
metadata[supportedHeader] = header.Get(canonicalHeader)
} else if _, ok := header[supportedHeader]; ok {
metadata[supportedHeader] = header.Get(supportedHeader)
}
}
// Go through all other headers for any additional headers that needs to be saved.
for key := range header {
cKey := http.CanonicalHeaderKey(key)
if strings.HasPrefix(cKey, "X-Amz-Meta-") {
metadata[cKey] = header.Get(key)
} else if strings.HasPrefix(key, "X-Minio-Meta-") {
metadata[cKey] = header.Get(key)
}
}
// Success.
return metadata
}
// The Query string for the redirect URL the client is
// redirected on successful upload.
func getRedirectPostRawQuery(objInfo ObjectInfo) string {
redirectValues := make(url.Values)
redirectValues.Set("bucket", objInfo.Bucket)
redirectValues.Set("key", objInfo.Name)
redirectValues.Set("etag", "\""+objInfo.MD5Sum+"\"")
return redirectValues.Encode()
}
// Extract request params to be sent with event notifiation.
func extractReqParams(r *http.Request) map[string]string {
if r == nil {
return nil
}
// Success.
return map[string]string{
"sourceIPAddress": r.RemoteAddr,
// Add more fields here.
}
}
// Trims away `aws-chunked` from the content-encoding header if present.
// Streaming signature clients can have custom content-encoding such as
// `aws-chunked,gzip` here we need to only save `gzip`.
// For more refer http://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-streaming.html
func trimAwsChunkedContentEncoding(contentEnc string) (trimmedContentEnc string) {
if contentEnc == "" {
return contentEnc
}
var newEncs []string
for _, enc := range strings.Split(contentEnc, ",") {
if enc != streamingContentEncoding {
newEncs = append(newEncs, enc)
}
}
return strings.Join(newEncs, ",")
}
// extractMetadataFromForm extracts metadata from Post Form.
func extractMetadataFromForm(formValues http.Header) map[string]string {
return extractMetadataFromHeader(formValues)
}
// Validate form field size for s3 specification requirement.
func validateFormFieldSize(formValues http.Header) error {
// Iterate over form values
for k := range formValues {
// Check if value's field exceeds S3 limit
if int64(len(formValues.Get(k))) > maxFormFieldSize {
return traceError(errSizeUnexpected)
}
}
// Success.
return nil
}
// Extract form fields and file data from a HTTP POST Policy
func extractPostPolicyFormValues(form *multipart.Form) (filePart io.ReadCloser, fileName string, fileSize int64, formValues http.Header, err error) {
/// HTML Form values
fileName = ""
// Canonicalize the form values into http.Header.
formValues = make(http.Header)
for k, v := range form.Value {
formValues[http.CanonicalHeaderKey(k)] = v
}
// Validate form values.
if err = validateFormFieldSize(formValues); err != nil {
return nil, "", 0, nil, err
}
// Iterator until we find a valid File field and break
for k, v := range form.File {
canonicalFormName := http.CanonicalHeaderKey(k)
if canonicalFormName == "File" {
if len(v) == 0 {
return nil, "", 0, nil, traceError(errInvalidArgument)
}
// Fetch fileHeader which has the uploaded file information
fileHeader := v[0]
// Set filename
fileName = fileHeader.Filename
// Open the uploaded part
filePart, err = fileHeader.Open()
if err != nil {
return nil, "", 0, nil, traceError(err)
}
// Compute file size
fileSize, err = filePart.(io.Seeker).Seek(0, 2)
if err != nil {
return nil, "", 0, nil, traceError(err)
}
// Reset Seek to the beginning
_, err = filePart.(io.Seeker).Seek(0, 0)
if err != nil {
return nil, "", 0, nil, traceError(err)
}
// File found and ready for reading
break
}
}
return filePart, fileName, fileSize, formValues, nil
}