Add bucketName checks for azure and s3 gateway in GetBucketInfo. (#4992)

Gateway interface implementations of GetBucketInfo() under
azure and s3 gateway did not perform any bucketname input
validation resulting in incorrect responses when the tests
are expecting InvalidBucketName.

Fixes #4983

cmd/gateway-azure-anonymous.go

@@ -133,10 +133,12 @@ func (a *azureObjects) AnonGetBucketInfo(bucket string) (bucketInfo BucketInfo,
 	if err != nil {
 		return bucketInfo, traceError(err)
 	}
+
 	bucketInfo = BucketInfo{
 		Name:    bucket,
 		Created: t,
 	}
+
 	return bucketInfo, nil
 }
 

cmd/gateway-azure.go

@@ -327,6 +327,14 @@ func (a *azureObjects) MakeBucketWithLocation(bucket, location string) error {
 
 // GetBucketInfo - Get bucket metadata..
 func (a *azureObjects) GetBucketInfo(bucket string) (bi BucketInfo, e error) {
+	// Verify if bucket (container-name) is valid.
+	// IsValidBucketName has same restrictions as container names mentioned
+	// in azure documentation, so we will simply use the same function here.
+	// Ref - https://docs.microsoft.com/en-us/rest/api/storageservices/naming-and-referencing-containers--blobs--and-metadata
+	if !IsValidBucketName(bucket) {
+		return bi, traceError(BucketNameInvalid{Bucket: bucket})
+	}
+
 	// Azure does not have an equivalent call, hence use
 	// ListContainers with prefix
 	resp, err := a.client.ListContainers(storage.ListContainersParameters{

cmd/gateway-gcs-anonymous.go

@@ -135,8 +135,14 @@ func (l *gcsGateway) AnonGetBucketInfo(bucket string) (bucketInfo BucketInfo, er
 		return bucketInfo, gcsToObjectError(traceError(anonErrToObjectErr(resp.StatusCode, bucket)), bucket)
 	}
 
+	t, err := time.Parse(time.RFC1123, resp.Header.Get("Last-Modified"))
+	if err != nil {
+		return bucketInfo, traceError(err)
+	}
+
 	// Last-Modified date being returned by GCS
 	return BucketInfo{
-		Name: bucket,
+		Name:    bucket,
+		Created: t,
 	}, nil
 }

cmd/gateway-s3.go

@@ -25,6 +25,7 @@ import (
 
 	minio "github.com/minio/minio-go"
 	"github.com/minio/minio-go/pkg/policy"
+	"github.com/minio/minio-go/pkg/s3utils"
 )
 
 // s3ToObjectError converts Minio errors to minio object layer errors.
@@ -161,6 +162,17 @@ func (l *s3Objects) MakeBucketWithLocation(bucket, location string) error {
 
 // GetBucketInfo gets bucket metadata..
 func (l *s3Objects) GetBucketInfo(bucket string) (bi BucketInfo, e error) {
+	// Verify if bucket name is valid.
+	// We are using a separate helper function here to validate bucket
+	// names instead of IsValidBucketName() because there is a possibility
+	// that certains users might have buckets which are non-DNS compliant
+	// in us-east-1 and we might severely restrict them by not allowing
+	// access to these buckets.
+	// Ref - http://docs.aws.amazon.com/AmazonS3/latest/dev/BucketRestrictions.html
+	if s3utils.CheckValidBucketName(bucket) != nil {
+		return bi, traceError(BucketNameInvalid{Bucket: bucket})
+	}
+
 	buckets, err := l.Client.ListBuckets()
 	if err != nil {
 		return bi, s3ToObjectError(traceError(err), bucket)