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allow tagging policy condition for GetObject (#15777)

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This commit is contained in:
Harshavardhana 2022-10-02 12:29:29 -07:00 committed by GitHub
parent ed5b67720c
commit f696a221af
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GPG Key ID: 4AEE18F83AFDEB23
10 changed files with 311 additions and 78 deletions
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28
cmd/admin-handlers-users_test.go
View File

@ -1203,6 +1203,34 @@ func (c *check) mustNotListObjects(ctx context.Context, client *minio.Client, bu
}
}
func (c *check) mustPutObjectWithTags(ctx context.Context, client *minio.Client, bucket, object string) {
c.Helper()
_, err := client.PutObject(ctx, bucket, object, bytes.NewBuffer([]byte("stuff")), 5, minio.PutObjectOptions{
UserTags: map[string]string{
"security": "public",
"virus": "true",
},
})
if err != nil {
c.Fatalf("user was unable to upload the object: %v", err)
}
}
func (c *check) mustGetObject(ctx context.Context, client *minio.Client, bucket, object string) {
c.Helper()
r, err := client.GetObject(ctx, bucket, object, minio.GetObjectOptions{})
if err != nil {
c.Fatalf("user was unable to download the object: %v", err)
}
defer r.Close()
_, err = io.Copy(io.Discard, r)
if err != nil {
c.Fatalf("user was unable to download the object: %v", err)
}
}
func (c *check) mustListObjects(ctx context.Context, client *minio.Client, bucket string) {
c.Helper()
res := client.ListObjects(ctx, bucket, minio.ListObjectsOptions{})

131
cmd/auth-handler.go
View File

@ -84,6 +84,8 @@ func isRequestSignStreamingV4(r *http.Request) bool {
}
// Authorization type.
//
//go:generate stringer -type=authType -trimprefix=authType $GOFILE
type authType int
// List of all supported auth types.
@ -293,24 +295,27 @@ func checkClaimsFromToken(r *http.Request, cred auth.Credentials) (map[string]in
//
// returns APIErrorCode if any to be replied to the client.
func checkRequestAuthType(ctx context.Context, r *http.Request, action policy.Action, bucketName, objectName string) (s3Err APIErrorCode) {
_, _, s3Err = checkRequestAuthTypeCredential(ctx, r, action, bucketName, objectName)
logger.GetReqInfo(ctx).BucketName = bucketName
logger.GetReqInfo(ctx).ObjectName = objectName
_, _, s3Err = checkRequestAuthTypeCredential(ctx, r, action)
return s3Err
}
// Check request auth type verifies the incoming http request
// - validates the request signature
// - validates the policy action if anonymous tests bucket policies if any,
// for authenticated requests validates IAM policies.
//
// returns APIErrorCode if any to be replied to the client.
// Additionally returns the accessKey used in the request, and if this request is by an admin.
func checkRequestAuthTypeCredential(ctx context.Context, r *http.Request, action policy.Action, bucketName, objectName string) (cred auth.Credentials, owner bool, s3Err APIErrorCode) {
func authenticateRequest(ctx context.Context, r *http.Request, action policy.Action) (s3Err APIErrorCode) {
if logger.GetReqInfo(ctx) == nil {
logger.LogIf(ctx, errors.New("unexpected context.Context does not have a logger.ReqInfo"), logger.Minio)
return ErrAccessDenied
}
var cred auth.Credentials
var owner bool
switch getRequestAuthType(r) {
case authTypeUnknown, authTypeStreamingSigned:
return cred, owner, ErrSignatureVersionNotSupported
return ErrSignatureVersionNotSupported
case authTypePresignedV2, authTypeSignedV2:
if s3Err = isReqAuthenticatedV2(r); s3Err != ErrNone {
return cred, owner, s3Err
return s3Err
}
cred, owner, s3Err = getReqAccessKeyV2(r)
case authTypeSigned, authTypePresigned:
@ -320,52 +325,67 @@ func checkRequestAuthTypeCredential(ctx context.Context, r *http.Request, action
region = ""
}
if s3Err = isReqAuthenticated(ctx, r, region, serviceS3); s3Err != ErrNone {
return cred, owner, s3Err
return s3Err
}
cred, owner, s3Err = getReqAccessKeyV4(r, region, serviceS3)
}
if s3Err != ErrNone {
return cred, owner, s3Err
return s3Err
}
// LocationConstraint is valid only for CreateBucketAction.
var locationConstraint string
logger.GetReqInfo(ctx).Cred = cred
logger.GetReqInfo(ctx).Owner = owner
// region is valid only for CreateBucketAction.
var region string
if action == policy.CreateBucketAction {
// To extract region from XML in request body, get copy of request body.
payload, err := io.ReadAll(io.LimitReader(r.Body, maxLocationConstraintSize))
if err != nil {
logger.LogIf(ctx, err, logger.Application)
return cred, owner, ErrMalformedXML
return ErrMalformedXML
}
// Populate payload to extract location constraint.
r.Body = io.NopCloser(bytes.NewReader(payload))
var s3Error APIErrorCode
locationConstraint, s3Error = parseLocationConstraint(r)
if s3Error != ErrNone {
return cred, owner, s3Error
region, s3Err = parseLocationConstraint(r)
if s3Err != ErrNone {
return s3Err
}
// Populate payload again to handle it in HTTP handler.
r.Body = io.NopCloser(bytes.NewReader(payload))
}
if cred.AccessKey != "" {
logger.GetReqInfo(ctx).AccessKey = cred.AccessKey
logger.GetReqInfo(ctx).Region = region
return s3Err
}
func authorizeRequest(ctx context.Context, r *http.Request, action policy.Action) (s3Err APIErrorCode) {
reqInfo := logger.GetReqInfo(ctx)
if reqInfo == nil {
return ErrAccessDenied
}
cred := reqInfo.Cred
owner := reqInfo.Owner
region := reqInfo.Region
bucket := reqInfo.BucketName
object := reqInfo.ObjectName
if action != policy.ListAllMyBucketsAction && cred.AccessKey == "" {
// Anonymous checks are not meant for ListBuckets action
// Anonymous checks are not meant for ListAllBuckets action
if globalPolicySys.IsAllowed(policy.Args{
AccountName: cred.AccessKey,
Action: action,
BucketName: bucketName,
ConditionValues: getConditionValues(r, locationConstraint, "", nil),
BucketName: bucket,
ConditionValues: getConditionValues(r, region, "", nil),
IsOwner: false,
ObjectName: objectName,
ObjectName: object,
}) {
// Request is allowed return the appropriate access key.
return cred, owner, ErrNone
return ErrNone
}
if action == policy.ListBucketVersionsAction {
@ -374,31 +394,31 @@ func checkRequestAuthTypeCredential(ctx context.Context, r *http.Request, action
if globalPolicySys.IsAllowed(policy.Args{
AccountName: cred.AccessKey,
Action: policy.ListBucketAction,
BucketName: bucketName,
ConditionValues: getConditionValues(r, locationConstraint, "", nil),
BucketName: bucket,
ConditionValues: getConditionValues(r, region, "", nil),
IsOwner: false,
ObjectName: objectName,
ObjectName: object,
}) {
// Request is allowed return the appropriate access key.
return cred, owner, ErrNone
return ErrNone
}
}
return cred, owner, ErrAccessDenied
return ErrAccessDenied
}
if globalIAMSys.IsAllowed(iampolicy.Args{
AccountName: cred.AccessKey,
Groups: cred.Groups,
Action: iampolicy.Action(action),
BucketName: bucketName,
BucketName: bucket,
ConditionValues: getConditionValues(r, "", cred.AccessKey, cred.Claims),
ObjectName: objectName,
ObjectName: object,
IsOwner: owner,
Claims: cred.Claims,
}) {
// Request is allowed return the appropriate access key.
return cred, owner, ErrNone
return ErrNone
}
if action == policy.ListBucketVersionsAction {
@ -408,18 +428,41 @@ func checkRequestAuthTypeCredential(ctx context.Context, r *http.Request, action
AccountName: cred.AccessKey,
Groups: cred.Groups,
Action: iampolicy.ListBucketAction,
BucketName: bucketName,
BucketName: bucket,
ConditionValues: getConditionValues(r, "", cred.AccessKey, cred.Claims),
ObjectName: objectName,
ObjectName: object,
IsOwner: owner,
Claims: cred.Claims,
}) {
// Request is allowed return the appropriate access key.
return cred, owner, ErrNone
return ErrNone
}
}
return cred, owner, ErrAccessDenied
return ErrAccessDenied
}
// Check request auth type verifies the incoming http request
// - validates the request signature
// - validates the policy action if anonymous tests bucket policies if any,
// for authenticated requests validates IAM policies.
//
// returns APIErrorCode if any to be replied to the client.
// Additionally returns the accessKey used in the request, and if this request is by an admin.
func checkRequestAuthTypeCredential(ctx context.Context, r *http.Request, action policy.Action) (cred auth.Credentials, owner bool, s3Err APIErrorCode) {
s3Err = authenticateRequest(ctx, r, action)
reqInfo := logger.GetReqInfo(ctx)
if reqInfo == nil {
return cred, owner, ErrAccessDenied
}
cred = reqInfo.Cred
owner = reqInfo.Owner
if s3Err != ErrNone {
return cred, owner, s3Err
}
return cred, owner, authorizeRequest(ctx, r, action)
}
// Verify if request has valid AWS Signature Version '2'.
@ -623,22 +666,22 @@ func isPutRetentionAllowed(bucketName, objectName string, retDays int, retDate t
func isPutActionAllowed(ctx context.Context, atype authType, bucketName, objectName string, r *http.Request, action iampolicy.Action) (s3Err APIErrorCode) {
var cred auth.Credentials
var owner bool
region := globalSite.Region
switch atype {
case authTypeUnknown:
return ErrSignatureVersionNotSupported
case authTypeSignedV2, authTypePresignedV2:
cred, owner, s3Err = getReqAccessKeyV2(r)
case authTypeStreamingSigned, authTypePresigned, authTypeSigned:
region := globalSite.Region
cred, owner, s3Err = getReqAccessKeyV4(r, region, serviceS3)
}
if s3Err != ErrNone {
return s3Err
}
if cred.AccessKey != "" {
logger.GetReqInfo(ctx).AccessKey = cred.AccessKey
}
logger.GetReqInfo(ctx).Cred = cred
logger.GetReqInfo(ctx).Owner = owner
logger.GetReqInfo(ctx).Region = region
// Do not check for PutObjectRetentionAction permission,
// if mode and retain until date are not set.

32
cmd/authtype_string.go Normal file
View File

@ -0,0 +1,32 @@
// Code generated by "stringer -type=authType -trimprefix=authType auth-handler.go"; DO NOT EDIT.
package cmd
import "strconv"
func _() {
// An "invalid array index" compiler error signifies that the constant values have changed.
// Re-run the stringer command to generate them again.
var x [1]struct{}
_ = x[authTypeUnknown-0]
_ = x[authTypeAnonymous-1]
_ = x[authTypePresigned-2]
_ = x[authTypePresignedV2-3]
_ = x[authTypePostPolicy-4]
_ = x[authTypeStreamingSigned-5]
_ = x[authTypeSigned-6]
_ = x[authTypeSignedV2-7]
_ = x[authTypeJWT-8]
_ = x[authTypeSTS-9]
}
const _authType_name = "UnknownAnonymousPresignedPresignedV2PostPolicyStreamingSignedSignedSignedV2JWTSTS"
var _authType_index = [...]uint8{0, 7, 16, 25, 36, 46, 61, 67, 75, 78, 81}
func (i authType) String() string {
if i < 0 || i >= authType(len(_authType_index)-1) {
return "authType(" + strconv.FormatInt(int64(i), 10) + ")"
}
return _authType_name[_authType_index[i]:_authType_index[i+1]]
}

4
cmd/bucket-handlers.go
View File

@ -300,7 +300,7 @@ func (api objectAPIHandlers) ListBucketsHandler(w http.ResponseWriter, r *http.R
listBuckets := objectAPI.ListBuckets
cred, owner, s3Error := checkRequestAuthTypeCredential(ctx, r, policy.ListAllMyBucketsAction, "", "")
cred, owner, s3Error := checkRequestAuthTypeCredential(ctx, r, policy.ListAllMyBucketsAction)
if s3Error != ErrNone && s3Error != ErrAccessDenied {
writeErrorResponse(ctx, w, errorCodes.ToAPIErr(s3Error), r.URL)
return
@ -731,7 +731,7 @@ func (api objectAPIHandlers) PutBucketHandler(w http.ResponseWriter, r *http.Req
}
}
cred, owner, s3Error := checkRequestAuthTypeCredential(ctx, r, policy.CreateBucketAction, bucket, "")
cred, owner, s3Error := checkRequestAuthTypeCredential(ctx, r, policy.CreateBucketAction)
if s3Error != ErrNone {
writeErrorResponse(ctx, w, errorCodes.ToAPIErr(s3Error), r.URL)
return

43
cmd/object-handlers.go
View File

@ -187,23 +187,25 @@ func (api objectAPIHandlers) SelectObjectContentHandler(w http.ResponseWriter, r
return
}
// Take read lock on object, here so subsequent lower-level
// calls do not need to.
lock := objectAPI.NewNSLock(bucket, object)
lkctx, err := lock.GetRLock(ctx, globalOperationTimeout)
if err != nil {
writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
return
}
ctx = lkctx.Context()
defer lock.RUnlock(lkctx.Cancel)
getObjectNInfo := objectAPI.GetObjectNInfo
if api.CacheAPI() != nil {
getObjectNInfo = api.CacheAPI().GetObjectNInfo
} else {
// Take read lock on object, here so subsequent lower-level
// calls do not need to.
lock := objectAPI.NewNSLock(bucket, object)
lkctx, err := lock.GetRLock(ctx, globalOperationTimeout)
if err != nil {
writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
return
}
ctx = lkctx.Context()
defer lock.RUnlock(lkctx.Cancel)
}
objInfo, err := getObjectInfo(ctx, bucket, object, opts)
gopts := opts
gopts.NoLock = true // We already have a lock, we can live with it.
objInfo, err := getObjectInfo(ctx, bucket, object, gopts)
if err != nil {
if globalBucketVersioningSys.PrefixEnabled(bucket, object) {
// Versioning enabled quite possibly object is deleted might be delete-marker
@ -342,7 +344,7 @@ func (api objectAPIHandlers) getObjectHandler(ctx context.Context, objectAPI Obj
// Check for auth type to return S3 compatible error.
// type to return the correct error (NoSuchKey vs AccessDenied)
if s3Error := checkRequestAuthType(ctx, r, policy.GetObjectAction, bucket, object); s3Error != ErrNone {
if s3Error := authenticateRequest(ctx, r, policy.GetObjectAction); s3Error != ErrNone {
if getRequestAuthType(r) == authTypeAnonymous {
// As per "Permission" section in
// https://docs.aws.amazon.com/AmazonS3/latest/API/RESTObjectGET.html
@ -442,6 +444,12 @@ func (api objectAPIHandlers) getObjectHandler(ctx context.Context, objectAPI Obj
}
}
if reader == nil || !proxy.Proxy {
// validate if the request indeed was authorized, if it wasn't we need to return "ErrAccessDenied"
// instead of any namespace related error.
if s3Error := authorizeRequest(ctx, r, policy.GetObjectAction); s3Error != ErrNone {
writeErrorResponse(ctx, w, errorCodes.ToAPIErr(s3Error), r.URL)
return
}
if isErrPreconditionFailed(err) {
return
}
@ -474,6 +482,15 @@ func (api objectAPIHandlers) getObjectHandler(ctx context.Context, objectAPI Obj
objInfo := gr.ObjInfo
if objInfo.UserTags != "" {
r.Header.Set(xhttp.AmzObjectTagging, objInfo.UserTags)
}
if s3Error := authorizeRequest(ctx, r, policy.GetObjectAction); s3Error != ErrNone {
writeErrorResponse(ctx, w, errorCodes.ToAPIErr(s3Error), r.URL)
return
}
if !proxy.Proxy { // apply lifecycle rules only for local requests
// Automatically remove the object/version is an expiry lifecycle rule can be applied
if lc, err := globalLifecycleSys.Get(bucket); err == nil {

112
cmd/sts-handlers_test.go
View File

@ -36,6 +36,7 @@ func runAllIAMSTSTests(suite *TestSuiteIAM, c *check) {
// The STS for root test needs to be the first one after setup.
suite.TestSTSForRoot(c)
suite.TestSTS(c)
suite.TestSTSWithTags(c)
suite.TestSTSWithGroupPolicy(c)
suite.TearDownSuite(c)
}
@ -72,6 +73,117 @@ func TestIAMInternalIDPSTSServerSuite(t *testing.T) {
}
}
func (s *TestSuiteIAM) TestSTSWithTags(c *check) {
ctx, cancel := context.WithTimeout(context.Background(), testDefaultTimeout)
defer cancel()
bucket := getRandomBucketName()
object := getRandomObjectName()
err := s.client.MakeBucket(ctx, bucket, minio.MakeBucketOptions{})
if err != nil {
c.Fatalf("bucket creat error: %v", err)
}
// Create policy, user and associate policy
policy := "mypolicy"
policyBytes := []byte(fmt.Sprintf(`{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": "s3:GetObject",
"Resource": "arn:aws:s3:::%s/*",
"Condition": { "StringEquals": {"s3:ExistingObjectTag/security": "public" } }
},
{
"Effect": "Allow",
"Action": "s3:DeleteObjectTagging",
"Resource": "arn:aws:s3:::%s/*",
"Condition": { "StringEquals": {"s3:ExistingObjectTag/security": "public" } }
},
{
"Effect": "Allow",
"Action": "s3:DeleteObject",
"Resource": "arn:aws:s3:::%s/*"
},
{
"Effect": "Allow",
"Action": [
"s3:PutObject"
],
"Resource": [
"arn:aws:s3:::%s/*"
],
"Condition": {
"ForAllValues:StringLike": {
"s3:RequestObjectTagKeys": [
"security",
"virus"
]
}
}
}
]
}`, bucket, bucket, bucket, bucket))
err = s.adm.AddCannedPolicy(ctx, policy, policyBytes)
if err != nil {
c.Fatalf("policy add error: %v", err)
}
accessKey, secretKey := mustGenerateCredentials(c)
err = s.adm.SetUser(ctx, accessKey, secretKey, madmin.AccountEnabled)
if err != nil {
c.Fatalf("Unable to set user: %v", err)
}
err = s.adm.SetPolicy(ctx, policy, accessKey, false)
if err != nil {
c.Fatalf("Unable to set policy: %v", err)
}
// confirm that the user is able to access the bucket
uClient := s.getUserClient(c, accessKey, secretKey, "")
c.mustPutObjectWithTags(ctx, uClient, bucket, object)
c.mustGetObject(ctx, uClient, bucket, object)
assumeRole := cr.STSAssumeRole{
Client: s.TestSuiteCommon.client,
STSEndpoint: s.endPoint,
Options: cr.STSAssumeRoleOptions{
AccessKey: accessKey,
SecretKey: secretKey,
Location: "",
},
}
value, err := assumeRole.Retrieve()
if err != nil {
c.Fatalf("err calling assumeRole: %v", err)
}
minioClient, err := minio.New(s.endpoint, &minio.Options{
Creds: cr.NewStaticV4(value.AccessKeyID, value.SecretAccessKey, value.SessionToken),
Secure: s.secure,
Transport: s.TestSuiteCommon.client.Transport,
})
if err != nil {
c.Fatalf("Error initializing client: %v", err)
}
// Validate sts creds can access the object
c.mustPutObjectWithTags(ctx, uClient, bucket, object)
c.mustGetObject(ctx, uClient, bucket, object)
// Validate that the client can remove objects
if err = minioClient.RemoveObjectTagging(ctx, bucket, object, minio.RemoveObjectTaggingOptions{}); err != nil {
c.Fatalf("user is unable to delete the object tags: %v", err)
}
if err = minioClient.RemoveObject(ctx, bucket, object, minio.RemoveObjectOptions{}); err != nil {
c.Fatalf("user is unable to delete the object: %v", err)
}
}
func (s *TestSuiteIAM) TestSTS(c *check) {
ctx, cancel := context.WithTimeout(context.Background(), testDefaultTimeout)
defer cancel()

4
cmd/utils.go
View File

@ -810,10 +810,6 @@ func newContext(r *http.Request, w http.ResponseWriter, api string) context.Cont
vars := mux.Vars(r)
bucket := vars["bucket"]
object := likelyUnescapeGeneric(vars["object"], url.PathUnescape)
prefix := likelyUnescapeGeneric(vars["prefix"], url.QueryUnescape)
if prefix != "" {
object = prefix
}
reqInfo := &logger.ReqInfo{
DeploymentID: globalDeploymentID,
RequestID: w.Header().Get(xhttp.AmzRequestID),

2
go.mod
View File

@ -49,7 +49,7 @@ require (
github.com/minio/kes v0.21.0
github.com/minio/madmin-go v1.4.29
github.com/minio/minio-go/v7 v7.0.40-0.20220928095841-8848d8affe8a
github.com/minio/pkg v1.4.2
github.com/minio/pkg v1.4.3
github.com/minio/selfupdate v0.5.0
github.com/minio/sha256-simd v1.0.0
github.com/minio/simdjson-go v0.4.2

4
go.sum
View File

@ -660,8 +660,8 @@ github.com/minio/minio-go/v7 v7.0.23/go.mod h1:ei5JjmxwHaMrgsMrn4U/+Nmg+d8MKS1U2
github.com/minio/minio-go/v7 v7.0.40-0.20220928095841-8848d8affe8a h1:COFh7S3tOKmJNYtKKFAuHQFH7MAaXxg4aAluXC9KQgc=
github.com/minio/minio-go/v7 v7.0.40-0.20220928095841-8848d8affe8a/go.mod h1:nCrRzjoSUQh8hgKKtu3Y708OLvRLtuASMg2/nvmbarw=
github.com/minio/pkg v1.1.20/go.mod h1:Xo7LQshlxGa9shKwJ7NzQbgW4s8T/Wc1cOStR/eUiMY=
github.com/minio/pkg v1.4.2 h1:QEToJld+cy+mMLDv084kIOgzjJQMbM+ioI/WotHeYQY=
github.com/minio/pkg v1.4.2/go.mod h1:mxCLAG+fOGIQr6odQ5Ukqc6qv9Zj6v1d6TD3NP82B7Y=
github.com/minio/pkg v1.4.3 h1:RJdhFj+5qK/oYuTuLGtTzn6GKniwI57eJ0LxrZ7xpw4=
github.com/minio/pkg v1.4.3/go.mod h1:mxCLAG+fOGIQr6odQ5Ukqc6qv9Zj6v1d6TD3NP82B7Y=
github.com/minio/selfupdate v0.5.0 h1:0UH1HlL49+2XByhovKl5FpYTjKfvrQ2sgL1zEXK6mfI=
github.com/minio/selfupdate v0.5.0/go.mod h1:mcDkzMgq8PRcpCRJo/NlPY7U45O5dfYl2Y0Rg7IustY=
github.com/minio/sha256-simd v0.1.1/go.mod h1:B5e1o+1/KgNmWrSQK08Y6Z1Vb5pwIktudl0J58iy0KM=

29
internal/logger/reqinfo.go
View File

@ -21,6 +21,8 @@ import (
"context"
"fmt"
"sync"
"github.com/minio/minio/internal/auth"
)
// Key used for Get/SetReqInfo
@ -43,18 +45,21 @@ type ObjectVersion struct {
// ReqInfo stores the request info.
// Reading/writing directly to struct requires appropriate R/W lock.
type ReqInfo struct {
RemoteHost string // Client Host/IP
Host string // Node Host/IP
UserAgent string // User Agent
DeploymentID string // x-minio-deployment-id
RequestID string // x-amz-request-id
API string // API name - GetObject PutObject NewMultipartUpload etc.
BucketName string `json:",omitempty"` // Bucket name
ObjectName string `json:",omitempty"` // Object name
VersionID string `json:",omitempty"` // corresponding versionID for the object
Objects []ObjectVersion `json:",omitempty"` // Only set during MultiObject delete handler.
AccessKey string // Access Key
tags []KeyVal // Any additional info not accommodated by above fields
RemoteHost string // Client Host/IP
Host string // Node Host/IP
UserAgent string // User Agent
DeploymentID string // x-minio-deployment-id
RequestID string // x-amz-request-id
API string // API name - GetObject PutObject NewMultipartUpload etc.
BucketName string `json:",omitempty"` // Bucket name
ObjectName string `json:",omitempty"` // Object name
VersionID string `json:",omitempty"` // corresponding versionID for the object
Objects []ObjectVersion `json:",omitempty"` // Only set during MultiObject delete handler.
Cred auth.Credentials `json:"-"`
Region string `json:"-"`
Owner bool `json:"-"`
AuthType string `json:"-"`
tags []KeyVal // Any additional info not accommodated by above fields
sync.RWMutex
}