Re-introduce backwards compatibility with Go 1.17 and Go 1.18

The following changes make use of methods that are not available in Go 1.17/Go 1.18. To guarantee at least 4 versions of backwards compatibility, versioned copies of those changes have been back-ported:
- 4d8db00641 (diff-4f6f6bdb9891d4dd271f9f31430420a2e44018fe4ee539576faf458bebb3cee4)
- 58158e990f (diff-772fc9f5d0c86f26e35158fb3e7a71a4967d18b4ec23a5dbb60781ab0babf426)
This commit is contained in:
Winni Neessen 2023-01-13 17:34:41 +01:00
parent 7cb34856a3
commit 8559e8c301
Signed by: wneessen
GPG key ID: 385AC9889632126E
5 changed files with 141 additions and 23 deletions

View file

@ -11,6 +11,9 @@
// //
// SPDX-License-Identifier: BSD-3-Clause AND MIT // SPDX-License-Identifier: BSD-3-Clause AND MIT
//go:build go1.19
// +build go1.19
package smtp package smtp
import ( import (

50
smtp/auth_cram_md5_118.go Normal file
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@ -0,0 +1,50 @@
// SPDX-FileCopyrightText: Copyright 2010 The Go Authors. All rights reserved.
// SPDX-FileCopyrightText: Copyright (c) 2022-2023 The go-mail Authors
//
// Original net/smtp code from the Go stdlib by the Go Authors.
// Use of this source code is governed by a BSD-style
// LICENSE file that can be found in this directory.
//
// go-mail specific modifications by the go-mail Authors.
// Licensed under the MIT License.
// See [PROJECT ROOT]/LICENSES directory for more information.
//
// SPDX-License-Identifier: BSD-3-Clause AND MIT
//go:build !go1.19
// +build !go1.19
package smtp
import (
"crypto/hmac"
"crypto/md5"
"fmt"
)
// cramMD5Auth is the type that satisfies the Auth interface for the "SMTP CRAM_MD5" auth
type cramMD5Auth struct {
username, secret string
}
// CRAMMD5Auth returns an Auth that implements the CRAM-MD5 authentication
// mechanism as defined in RFC 2195.
// The returned Auth uses the given username and secret to authenticate
// to the server using the challenge-response mechanism.
func CRAMMD5Auth(username, secret string) Auth {
return &cramMD5Auth{username, secret}
}
func (a *cramMD5Auth) Start(_ *ServerInfo) (string, []byte, error) {
return "CRAM-MD5", nil, nil
}
func (a *cramMD5Auth) Next(fromServer []byte, more bool) ([]byte, error) {
if more {
d := hmac.New(md5.New, []byte(a.secret))
d.Write(fromServer)
s := make([]byte, 0, d.Size())
return []byte(fmt.Sprintf("%s %x", a.username, d.Sum(s))), nil
}
return nil, nil
}

View file

@ -137,29 +137,6 @@ func (c *Client) helo() error {
return err return err
} }
// ehlo sends the EHLO (extended hello) greeting to the server. It
// should be the preferred greeting for servers that support it.
func (c *Client) ehlo() error {
_, msg, err := c.cmd(250, "EHLO %s", c.localName)
if err != nil {
return err
}
ext := make(map[string]string)
extList := strings.Split(msg, "\n")
if len(extList) > 1 {
extList = extList[1:]
for _, line := range extList {
k, v, _ := strings.Cut(line, " ")
ext[k] = v
}
}
if mechs, ok := ext["AUTH"]; ok {
c.auth = strings.Split(mechs, " ")
}
c.ext = ext
return err
}
// StartTLS sends the STARTTLS command and encrypts all further communication. // StartTLS sends the STARTTLS command and encrypts all further communication.
// Only servers that advertise the STARTTLS extension support this function. // Only servers that advertise the STARTTLS extension support this function.
func (c *Client) StartTLS(config *tls.Config) error { func (c *Client) StartTLS(config *tls.Config) error {

42
smtp/smtp_ehlo.go Normal file
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@ -0,0 +1,42 @@
// SPDX-FileCopyrightText: Copyright 2010 The Go Authors. All rights reserved.
// SPDX-FileCopyrightText: Copyright (c) 2022-2023 The go-mail Authors
//
// Original net/smtp code from the Go stdlib by the Go Authors.
// Use of this source code is governed by a BSD-style
// LICENSE file that can be found in this directory.
//
// go-mail specific modifications by the go-mail Authors.
// Licensed under the MIT License.
// See [PROJECT ROOT]/LICENSES directory for more information.
//
// SPDX-License-Identifier: BSD-3-Clause AND MIT
//go:build go1.18
// +build go1.18
package smtp
import "strings"
// ehlo sends the EHLO (extended hello) greeting to the server. It
// should be the preferred greeting for servers that support it.
func (c *Client) ehlo() error {
_, msg, err := c.cmd(250, "EHLO %s", c.localName)
if err != nil {
return err
}
ext := make(map[string]string)
extList := strings.Split(msg, "\n")
if len(extList) > 1 {
extList = extList[1:]
for _, line := range extList {
k, v, _ := strings.Cut(line, " ")
ext[k] = v
}
}
if mechs, ok := ext["AUTH"]; ok {
c.auth = strings.Split(mechs, " ")
}
c.ext = ext
return err
}

46
smtp/smtp_ehlo_117.go Normal file
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@ -0,0 +1,46 @@
// SPDX-FileCopyrightText: Copyright 2010 The Go Authors. All rights reserved.
// SPDX-FileCopyrightText: Copyright (c) 2022-2023 The go-mail Authors
//
// Original net/smtp code from the Go stdlib by the Go Authors.
// Use of this source code is governed by a BSD-style
// LICENSE file that can be found in this directory.
//
// go-mail specific modifications by the go-mail Authors.
// Licensed under the MIT License.
// See [PROJECT ROOT]/LICENSES directory for more information.
//
// SPDX-License-Identifier: BSD-3-Clause AND MIT
//go:build !go1.18
// +build !go1.18
package smtp
import "strings"
// ehlo sends the EHLO (extended hello) greeting to the server. It
// should be the preferred greeting for servers that support it.
func (c *Client) ehlo() error {
_, msg, err := c.cmd(250, "EHLO %s", c.localName)
if err != nil {
return err
}
ext := make(map[string]string)
extList := strings.Split(msg, "\n")
if len(extList) > 1 {
extList = extList[1:]
for _, line := range extList {
args := strings.SplitN(line, " ", 2)
if len(args) > 1 {
ext[args[0]] = args[1]
} else {
ext[args[0]] = ""
}
}
}
if mechs, ok := ext["AUTH"]; ok {
c.auth = strings.Split(mechs, " ")
}
c.ext = ext
return err
}