vendor: move vendored sources in-tree

This should make it easier to see changes instead of just a blob

vendor/github.com/rabbitmq/amqp091-go/auth.go

@@ -0,0 +1,83 @@
+// Copyright (c) 2021 VMware, Inc. or its affiliates. All Rights Reserved.
+// Copyright (c) 2012-2021, Sean Treadway, SoundCloud Ltd.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package amqp091
+
+import (
+	"bytes"
+	"fmt"
+)
+
+// Authentication interface provides a means for different SASL authentication
+// mechanisms to be used during connection tuning.
+type Authentication interface {
+	Mechanism() string
+	Response() string
+}
+
+// PlainAuth is a similar to Basic Auth in HTTP.
+type PlainAuth struct {
+	Username string
+	Password string
+}
+
+// Mechanism returns "PLAIN"
+func (auth *PlainAuth) Mechanism() string {
+	return "PLAIN"
+}
+
+// Response returns the null character delimited encoding for the SASL PLAIN Mechanism.
+func (auth *PlainAuth) Response() string {
+	return fmt.Sprintf("\000%s\000%s", auth.Username, auth.Password)
+}
+
+// AMQPlainAuth is similar to PlainAuth
+type AMQPlainAuth struct {
+	Username string
+	Password string
+}
+
+// Mechanism returns "AMQPLAIN"
+func (auth *AMQPlainAuth) Mechanism() string {
+	return "AMQPLAIN"
+}
+
+// Response returns an AMQP encoded credentials table, without the field table size.
+func (auth *AMQPlainAuth) Response() string {
+	var buf bytes.Buffer
+	table := Table{"LOGIN": auth.Username, "PASSWORD": auth.Password}
+	if err := writeTable(&buf, table); err != nil {
+		return ""
+	}
+	return buf.String()[4:]
+}
+
+// ExternalAuth for RabbitMQ-auth-mechanism-ssl.
+type ExternalAuth struct {
+}
+
+// Mechanism returns "EXTERNAL"
+func (*ExternalAuth) Mechanism() string {
+	return "EXTERNAL"
+}
+
+// Response returns an AMQP encoded credentials table, without the field table size.
+func (*ExternalAuth) Response() string {
+	return "\000*\000*"
+}
+
+// Finds the first mechanism preferred by the client that the server supports.
+func pickSASLMechanism(client []Authentication, serverMechanisms []string) (auth Authentication, ok bool) {
+
+	for _, auth = range client {
+		for _, mech := range serverMechanisms {
+			if auth.Mechanism() == mech {
+				return auth, true
+			}
+		}
+	}
+
+	return
+}