restic/vendor/github.com/minio/minio-go/api-presigned.go

212 lines
6.5 KiB
Go

/*
* Minio Go Library for Amazon S3 Compatible Cloud Storage (C) 2015, 2016 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 minio
import (
"errors"
"net/url"
"time"
"github.com/minio/minio-go/pkg/s3signer"
"github.com/minio/minio-go/pkg/s3utils"
)
// supportedGetReqParams - supported request parameters for GET presigned request.
var supportedGetReqParams = map[string]struct{}{
"response-expires": {},
"response-content-type": {},
"response-cache-control": {},
"response-content-language": {},
"response-content-encoding": {},
"response-content-disposition": {},
}
// presignURL - Returns a presigned URL for an input 'method'.
// Expires maximum is 7days - ie. 604800 and minimum is 1.
func (c Client) presignURL(method string, bucketName string, objectName string, expires time.Duration, reqParams url.Values) (u *url.URL, err error) {
// Input validation.
if method == "" {
return nil, ErrInvalidArgument("method cannot be empty.")
}
if err := s3utils.CheckValidBucketName(bucketName); err != nil {
return nil, err
}
if err := s3utils.CheckValidObjectName(objectName); err != nil {
return nil, err
}
if err := isValidExpiry(expires); err != nil {
return nil, err
}
// Convert expires into seconds.
expireSeconds := int64(expires / time.Second)
reqMetadata := requestMetadata{
presignURL: true,
bucketName: bucketName,
objectName: objectName,
expires: expireSeconds,
}
// For "GET" we are handling additional request parameters to
// override its response headers.
if method == "GET" {
// Verify if input map has unsupported params, if yes exit.
for k := range reqParams {
if _, ok := supportedGetReqParams[k]; !ok {
return nil, ErrInvalidArgument(k + " unsupported request parameter for presigned GET.")
}
}
// Save the request parameters to be used in presigning for GET request.
reqMetadata.queryValues = reqParams
}
// Instantiate a new request.
// Since expires is set newRequest will presign the request.
req, err := c.newRequest(method, reqMetadata)
if err != nil {
return nil, err
}
return req.URL, nil
}
// PresignedGetObject - Returns a presigned URL to access an object
// without credentials. Expires maximum is 7days - ie. 604800 and
// minimum is 1. Additionally you can override a set of response
// headers using the query parameters.
func (c Client) PresignedGetObject(bucketName string, objectName string, expires time.Duration, reqParams url.Values) (u *url.URL, err error) {
return c.presignURL("GET", bucketName, objectName, expires, reqParams)
}
// PresignedPutObject - Returns a presigned URL to upload an object without credentials.
// Expires maximum is 7days - ie. 604800 and minimum is 1.
func (c Client) PresignedPutObject(bucketName string, objectName string, expires time.Duration) (u *url.URL, err error) {
return c.presignURL("PUT", bucketName, objectName, expires, nil)
}
// PresignedPostPolicy - Returns POST urlString, form data to upload an object.
func (c Client) PresignedPostPolicy(p *PostPolicy) (u *url.URL, formData map[string]string, err error) {
// Validate input arguments.
if p.expiration.IsZero() {
return nil, nil, errors.New("Expiration time must be specified")
}
if _, ok := p.formData["key"]; !ok {
return nil, nil, errors.New("object key must be specified")
}
if _, ok := p.formData["bucket"]; !ok {
return nil, nil, errors.New("bucket name must be specified")
}
bucketName := p.formData["bucket"]
// Fetch the bucket location.
location, err := c.getBucketLocation(bucketName)
if err != nil {
return nil, nil, err
}
u, err = c.makeTargetURL(bucketName, "", location, nil)
if err != nil {
return nil, nil, err
}
// Get credentials from the configured credentials provider.
credValues, err := c.credsProvider.Get()
if err != nil {
return nil, nil, err
}
var (
signerType = credValues.SignerType
sessionToken = credValues.SessionToken
accessKeyID = credValues.AccessKeyID
secretAccessKey = credValues.SecretAccessKey
)
if signerType.IsAnonymous() {
return nil, nil, ErrInvalidArgument("Presigned operations are not supported for anonymous credentials")
}
// Keep time.
t := time.Now().UTC()
// For signature version '2' handle here.
if signerType.IsV2() {
policyBase64 := p.base64()
p.formData["policy"] = policyBase64
// For Google endpoint set this value to be 'GoogleAccessId'.
if s3utils.IsGoogleEndpoint(c.endpointURL) {
p.formData["GoogleAccessId"] = accessKeyID
} else {
// For all other endpoints set this value to be 'AWSAccessKeyId'.
p.formData["AWSAccessKeyId"] = accessKeyID
}
// Sign the policy.
p.formData["signature"] = s3signer.PostPresignSignatureV2(policyBase64, secretAccessKey)
return u, p.formData, nil
}
// Add date policy.
if err = p.addNewPolicy(policyCondition{
matchType: "eq",
condition: "$x-amz-date",
value: t.Format(iso8601DateFormat),
}); err != nil {
return nil, nil, err
}
// Add algorithm policy.
if err = p.addNewPolicy(policyCondition{
matchType: "eq",
condition: "$x-amz-algorithm",
value: signV4Algorithm,
}); err != nil {
return nil, nil, err
}
// Add a credential policy.
credential := s3signer.GetCredential(accessKeyID, location, t)
if err = p.addNewPolicy(policyCondition{
matchType: "eq",
condition: "$x-amz-credential",
value: credential,
}); err != nil {
return nil, nil, err
}
if sessionToken != "" {
if err = p.addNewPolicy(policyCondition{
matchType: "eq",
condition: "$x-amz-security-token",
value: sessionToken,
}); err != nil {
return nil, nil, err
}
}
// Get base64 encoded policy.
policyBase64 := p.base64()
// Fill in the form data.
p.formData["policy"] = policyBase64
p.formData["x-amz-algorithm"] = signV4Algorithm
p.formData["x-amz-credential"] = credential
p.formData["x-amz-date"] = t.Format(iso8601DateFormat)
if sessionToken != "" {
p.formData["x-amz-security-token"] = sessionToken
}
p.formData["x-amz-signature"] = s3signer.PostPresignSignatureV4(policyBase64, t, secretAccessKey, location)
return u, p.formData, nil
}