return subtle.ConstantTimeCompare([]byte(sig1), []byte(sig2)) == 1
}

// doesPolicySignatureMatch - Verify query headers with post policy
//   - http://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-HTTPPOSTConstructPolicy.html
//
// returns ErrNone if the signature matches.
func doesPolicySignatureV4Match(formValues http.Header) (auth.Credentials, APIErrorCode) {
	// Server region.
	region := globalSite.Region

	}
	return secret, nil
}

// AssumeRole - implementation of AWS STS API AssumeRole to get temporary
// credentials for regular users on Minio.
// https://docs.aws.amazon.com/STS/latest/APIReference/API_AssumeRole.html
func (sts *stsAPIHandlers) AssumeRole(w http.ResponseWriter, r *http.Request) {
	ctx := newContext(r, w, "AssumeRole")

	claims := make(map[string]interface{})
	defer logger.AuditLog(ctx, w, r, claims)

	}

	*dr = DefaultRetention(retention)

	return nil
}

// Config - object lock configuration specified in
// https://docs.aws.amazon.com/AmazonS3/latest/API/Type_API_ObjectLockConfiguration.html
type Config struct {
	XMLNS             string   `xml:"xmlns,attr,omitempty"`
	XMLName           xml.Name `xml:"ObjectLockConfiguration"`
	ObjectLockEnabled string   `xml:"ObjectLockEnabled"`
	Rule              *struct {

				// once delete markers are old enough to satisfy the age criteria.
				// https://docs.aws.amazon.com/AmazonS3/latest/userguide/lifecycle-configuration-examples.html
				if expectedExpiry := ExpectedExpiryTime(obj.ModTime, int(rule.Expiration.Days)); now.IsZero() || now.After(expectedExpiry) {
					events = append(events, Event{
						Action: DeleteVersionAction,
						RuleID: rule.ID,

	// 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

	// maxBuckets upto 500000 for any MinIO deployment.
	maxBuckets = 500 * 1000
)

		if getRequestAuthType(r) == authTypeAnonymous {
			// As per "Permission" section in
			// https://docs.aws.amazon.com/AmazonS3/latest/API/RESTObjectGET.html
			// If the object you request does not exist,
			// the error Amazon S3 returns depends on
			// whether you also have the s3:ListBucket
			// permission.
			// * If you have the s3:ListBucket permission

					return ObjectLocked{}
				}

				if !ret.RetainUntilDate.Before(t) {
					return ObjectLocked{}
				}
				return nil
			}
			// https://docs.aws.amazon.com/AmazonS3/latest/dev/object-lock-overview.html#object-lock-retention-modes
			// If you try to delete objects protected by governance mode and have s3:BypassGovernanceRetention, the operation will succeed.

}

// Signature and API related constants.
const (
	signV2Algorithm = "AWS"
)

// AWS S3 Signature V2 calculation rule is give here:
// http://docs.aws.amazon.com/AmazonS3/latest/dev/RESTAuthentication.html#RESTAuthenticationStringToSign
func doesPolicySignatureV2Match(formValues http.Header) (auth.Credentials, APIErrorCode) {
	accessKey := formValues.Get(xhttp.AmzAccessKeyID)

	r := &http.Request{Header: formValues}

			default:
				logger.Default.Warn(context.Background(), "Model %v don't match %vInterface, should be `%v(*gorm.DB) error`. Please see https://gorm.io/docs/hooks.html", schema, cbName, cbName)
			}
		}
	}

	// Cache the schema
	if v, loaded := cacheStore.LoadOrStore(schemaCacheKey, schema); loaded {
		s := v.(*Schema)

	newSignature := getSignature(signingKey, stringToSign)

	return newSignature
}

// calculateSeedSignature - Calculate seed signature in accordance with
//   - http://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-streaming.html
//
// returns signature, error otherwise if the signature mismatches or any other
// error while parsing and validating.