Internet Engineering Task Force (IETF)                         J. Levine
Request for Comments: 8463                          Taughannock Networks
Updates: 6376                                             September 2018
Category: Standards Track
ISSN: 2070-1721
        
Internet Engineering Task Force (IETF)                         J. Levine
Request for Comments: 8463                          Taughannock Networks
Updates: 6376                                             September 2018
Category: Standards Track
ISSN: 2070-1721
        

A New Cryptographic Signature Method for DomainKeys Identified Mail (DKIM)

一种新的域密钥识别邮件加密签名方法(DKIM)

Abstract

摘要

This document adds a new signing algorithm, Ed25519-SHA256, to "DomainKeys Identified Mail (DKIM) Signatures" (RFC 6376). DKIM verifiers are required to implement this algorithm.

本文档在“域密钥识别邮件(DKIM)签名”(RFC 6376)中添加了一个新的签名算法Ed25519-SHA256。需要DKIM验证器来实现该算法。

Status of This Memo

关于下段备忘

This is an Internet Standards Track document.

这是一份互联网标准跟踪文件。

This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841.

本文件是互联网工程任务组(IETF)的产品。它代表了IETF社区的共识。它已经接受了公众审查,并已被互联网工程指导小组(IESG)批准出版。有关互联网标准的更多信息,请参见RFC 7841第2节。

Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc8463.

有关本文件当前状态、任何勘误表以及如何提供反馈的信息,请访问https://www.rfc-editor.org/info/rfc8463.

Copyright Notice

版权公告

Copyright (c) 2018 IETF Trust and the persons identified as the document authors. All rights reserved.

版权所有(c)2018 IETF信托基金和确定为文件作者的人员。版权所有。

This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.

本文件受BCP 78和IETF信托有关IETF文件的法律规定的约束(https://trustee.ietf.org/license-info)自本文件出版之日起生效。请仔细阅读这些文件,因为它们描述了您对本文件的权利和限制。从本文件中提取的代码组件必须包括信托法律条款第4.e节中所述的简化BSD许可证文本,并提供简化BSD许可证中所述的无担保。

Table of Contents

目录

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions Used in This Document . . . . . . . . . . . . . .   2
   3.  Ed25519-SHA256 Signing Algorithm  . . . . . . . . . . . . . .   3
   4.  Signature and Key Syntax  . . . . . . . . . . . . . . . . . .   3
     4.1.  Signature Syntax  . . . . . . . . . . . . . . . . . . . .   3
     4.2.  Key Syntax  . . . . . . . . . . . . . . . . . . . . . . .   3
   5.  Choice and Strength of Keys and Algorithms  . . . . . . . . .   4
   6.  Transition Considerations . . . . . . . . . . . . . . . . . .   4
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .   4
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   4
     8.1.  "DKIM Key Type" Registry  . . . . . . . . . . . . . . . .   4
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   5
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .   5
     9.2.  Informative References  . . . . . . . . . . . . . . . . .   5
   Appendix A.  Example of a Signed Message  . . . . . . . . . . . .   6
     A.1.  Secret Keys . . . . . . . . . . . . . . . . . . . . . . .   6
     A.2.  Public Key DNS Records  . . . . . . . . . . . . . . . . .   6
     A.3.  Signed Message  . . . . . . . . . . . . . . . . . . . . .   7
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .   7
        
   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions Used in This Document . . . . . . . . . . . . . .   2
   3.  Ed25519-SHA256 Signing Algorithm  . . . . . . . . . . . . . .   3
   4.  Signature and Key Syntax  . . . . . . . . . . . . . . . . . .   3
     4.1.  Signature Syntax  . . . . . . . . . . . . . . . . . . . .   3
     4.2.  Key Syntax  . . . . . . . . . . . . . . . . . . . . . . .   3
   5.  Choice and Strength of Keys and Algorithms  . . . . . . . . .   4
   6.  Transition Considerations . . . . . . . . . . . . . . . . . .   4
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .   4
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   4
     8.1.  "DKIM Key Type" Registry  . . . . . . . . . . . . . . . .   4
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   5
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .   5
     9.2.  Informative References  . . . . . . . . . . . . . . . . .   5
   Appendix A.  Example of a Signed Message  . . . . . . . . . . . .   6
     A.1.  Secret Keys . . . . . . . . . . . . . . . . . . . . . . .   6
     A.2.  Public Key DNS Records  . . . . . . . . . . . . . . . . .   6
     A.3.  Signed Message  . . . . . . . . . . . . . . . . . . . . .   7
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .   7
        
1. Introduction
1. 介绍

DKIM [RFC6376] signs email messages by creating hashes of selected message header fields and body and signing the header hash with a digital signature. Message recipients fetch the signature verification key from the DNS. The defining documents specify a single signing algorithm, RSA [RFC3447] (which has since been obsoleted by [RFC8017]).

DKIM[RFC6376]通过创建选定邮件标题字段和正文的散列,并使用数字签名对标题散列进行签名,从而对电子邮件进行签名。消息收件人从DNS获取签名验证密钥。定义文档指定了单一签名算法RSA[RFC3447](该算法已被[RFC8017]淘汰)。

This document adds a new, stronger signing algorithm, Edwards-Curve Digital Signature Algorithm, using the Curve25519 curve (Ed25519), which has much shorter keys than RSA for similar levels of security.

本文档使用Curve2519 Curve(Ed25519)添加了一种新的、更强大的签名算法,即Edwards Curve数字签名算法,该算法的密钥比RSA短得多,具有相似的安全级别。

2. Conventions Used in This Document
2. 本文件中使用的公约

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.

本文件中的关键词“必须”、“不得”、“必需”、“应”、“不应”、“建议”、“不建议”、“可”和“可选”在所有大写字母出现时(如图所示)应按照BCP 14[RFC2119][RFC8174]所述进行解释。

Syntax descriptions use Augmented BNF (ABNF) [RFC5234]. The ABNF tokens sig-a-tag-k and key-k-tag-type are imported from [RFC6376].

语法描述使用增广的BNF(ABNF)[RFC5234]。ABNF令牌sig-a-tag-k和key-k-tag-type从[RFC6376]导入。

3. Ed25519-SHA256 Signing Algorithm
3. Ed25519-SHA256签名算法

The Ed25519-SHA256 signing algorithm computes a message hash as defined in Section 3 of [RFC6376] using SHA-256 [FIPS-180-4-2015] as the hash-alg. It signs the hash with the PureEdDSA variant Ed25519, as defined in RFC 8032, Section 5.1 [RFC8032]. Example keys and signatures in Appendix A are based on the test vectors in RFC 8032, Section 7.1 [RFC8032].

Ed25519-SHA256签名算法使用SHA-256[FIPS-180-4-2015]作为哈希alg,计算[RFC6376]第3节中定义的消息哈希。它使用PureEdDSA变量Ed25519对哈希进行签名,如RFC 8032第5.1节[RFC8032]中所定义。附录A中的示例键和签名基于RFC 8032第7.1节[RFC8032]中的测试向量。

The DNS record for the verification public key has a "k=ed25519" tag to indicate that the key is an Ed25519 rather than an RSA key.

验证公钥的DNS记录有一个“k=ed25519”标记,表示该密钥是ed25519而不是RSA密钥。

This is an additional DKIM signature algorithm added to Section 3.3 of [RFC6376] as envisioned in Section 3.3.4 of that document.

这是[RFC6376]第3.3节中增加的附加DKIM签名算法,如该文件第3.3.4节所述。

Note: since Ed25519 public keys are 256 bits long, the base64-encoded key is only 44 octets, so DNS key record data will generally fit in a single 255-byte TXT string and work even with DNS provisioning software that doesn't handle multistring TXT records.

注意:由于Ed25519公钥长度为256位,base64编码密钥仅为44个八位字节,因此DNS密钥记录数据通常适合于单个255字节的TXT字符串,甚至可以与不处理多字符串TXT记录的DNS配置软件一起使用。

4. Signature and Key Syntax
4. 签名和密钥语法

The syntax of DKIM signatures and DKIM keys are updated as follows.

DKIM签名和DKIM密钥的语法更新如下。

4.1. Signature Syntax
4.1. 签名语法

The syntax of DKIM algorithm tags in Section 3.5 of [RFC6376] is updated by adding this rule to the existing rule for sig-a-tag-k:

[RFC6376]第3.5节中DKIM算法标记的语法通过将此规则添加到sig-a-tag-k的现有规则中进行更新:

ABNF:

荷兰银行:

sig-a-tag-k =/ "ed25519"

sig-a-tag-k=/“ed25519”

4.2. Key Syntax
4.2. 键语法

The syntax of DKIM key tags in Section 3.6.1 of [RFC6376] is updated by adding this rule to the existing rule for key-k-tag-type:

[RFC6376]第3.6.1节中DKIM键标记的语法通过将此规则添加到键-k-tag-type的现有规则中进行更新:

ABNF:

荷兰银行:

key-k-tag-type =/ "ed25519"

key-k-tag-type=/“ed25519”

The p= value in the key record is the Ed25519 public key encoded in base64. Since the key is 256 bits long, the base64 text is 44 octets long. See Appendix A.2 for a sample key record using the public key in [RFC8032], Section 7.1, Test 1.

密钥记录中的p=值是用base64编码的Ed25519公钥。由于密钥长度为256位,因此base64文本长度为44个八位字节。参见附录A.2,获取[RFC8032]第7.1节测试1中使用公钥的示例密钥记录。

5. Choice and Strength of Keys and Algorithms
5. 密钥和算法的选择和强度

Section 3.3 of [RFC6376] describes DKIM's hash and signature algorithms. It is updated as follows:

[RFC6376]的第3.3节描述了DKIM的哈希和签名算法。更新内容如下:

Signers SHOULD implement and verifiers MUST implement the Ed25519-SHA256 algorithm.

签名者应实现,验证者必须实现Ed25519-SHA256算法。

6. Transition Considerations
6. 过渡考虑

For backward compatibility, signers can add multiple signatures that use old and new signing algorithms. Since there can only be a single key record in the DNS for each selector, the signatures have to use different selectors, although they can use the same d= and i= identifiers.

为了向后兼容,签名者可以添加使用新旧签名算法的多个签名。由于每个选择器在DNS中只能有一个密钥记录,因此签名必须使用不同的选择器,尽管它们可以使用相同的d=和i=标识符。

The example message in Appendix A has two signatures with the same d= and i= identifiers but different a= algorithms and s= selectors.

附录A中的示例消息有两个签名,具有相同的d=和i=标识符,但不同的A=算法和s=选择器。

7. Security Considerations
7. 安全考虑

All of the security advice in [RFC6376] continues to apply, except that the security advice about Ed25519 in Section 8 of [RFC8032] supplants the advice about RSA threats.

[RFC6376]中的所有安全建议继续适用,但[RFC8032]第8节中关于Ed25519的安全建议取代了关于RSA威胁的建议。

8. IANA Considerations
8. IANA考虑

IANA has updated a registry as follows.

IANA更新了一个注册表,如下所示。

8.1. "DKIM Key Type" Registry
8.1. “DKIM密钥类型”注册表

The following value has been added to the "DKIM Key Type" registry:

以下值已添加到“DKIM密钥类型”注册表中:

                     +---------+-----------+--------+
                     |   TYPE  | REFERENCE | STATUS |
                     +---------+-----------+--------+
                     | ed25519 | [RFC8032] | active |
                     +---------+-----------+--------+
        
                     +---------+-----------+--------+
                     |   TYPE  | REFERENCE | STATUS |
                     +---------+-----------+--------+
                     | ed25519 | [RFC8032] | active |
                     +---------+-----------+--------+
        

Table 1: Value Added to the "DKIM Key Type" Registry

表1:添加到“DKIM密钥类型”注册表的值

9. References
9. 工具书类
9.1. Normative References
9.1. 规范性引用文件

[FIPS-180-4-2015] National Institute of Standards and Technology, "Secure Hash Standard (SHS)", FIPS PUB 180-4, DOI 10.6028/NIST.FIPS.180-4, August 2015, <http://nvlpubs.nist.gov/nistpubs/FIPS/ NIST.FIPS.180-4.pdf>.

[FIPS-180-4-2015]国家标准与技术研究所,“安全哈希标准(SHS)”,FIPS PUB 180-4,DOI 10.6028/NIST.FIPS.180-42015年8月<http://nvlpubs.nist.gov/nistpubs/FIPS/ NIST.FIPS.180-4.pdf>。

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, <https://www.rfc-editor.org/info/rfc2119>.

[RFC2119]Bradner,S.,“RFC中用于表示需求水平的关键词”,BCP 14,RFC 2119,DOI 10.17487/RFC2119,1997年3月<https://www.rfc-editor.org/info/rfc2119>.

[RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", STD 68, RFC 5234, DOI 10.17487/RFC5234, January 2008, <https://www.rfc-editor.org/info/rfc5234>.

[RFC5234]Crocker,D.,Ed.和P.Overell,“语法规范的扩充BNF:ABNF”,STD 68,RFC 5234,DOI 10.17487/RFC5234,2008年1月<https://www.rfc-editor.org/info/rfc5234>.

[RFC6376] Crocker, D., Ed., Hansen, T., Ed., and M. Kucherawy, Ed., "DomainKeys Identified Mail (DKIM) Signatures", STD 76, RFC 6376, DOI 10.17487/RFC6376, September 2011, <https://www.rfc-editor.org/info/rfc6376>.

[RFC6376]Crocker,D.,Ed.,Hansen,T.,Ed.,和M.Kucherawy,Ed.,“域密钥识别邮件(DKIM)签名”,STD 76,RFC 6376,DOI 10.17487/RFC6376,2011年9月<https://www.rfc-editor.org/info/rfc6376>.

[RFC8017] Moriarty, K., Ed., Kaliski, B., Jonsson, J., and A. Rusch, "PKCS #1: RSA Cryptography Specifications Version 2.2", RFC 8017, DOI 10.17487/RFC8017, November 2016, <https://www.rfc-editor.org/info/rfc8017>.

[RFC8017]Moriarty,K.,Ed.,Kaliski,B.,Jonsson,J.,和A.Rusch,“PKCS#1:RSA加密规范版本2.2”,RFC 8017,DOI 10.17487/RFC8017,2016年11月<https://www.rfc-editor.org/info/rfc8017>.

[RFC8032] Josefsson, S. and I. Liusvaara, "Edwards-Curve Digital Signature Algorithm (EdDSA)", RFC 8032, DOI 10.17487/RFC8032, January 2017, <https://www.rfc-editor.org/info/rfc8032>.

[RFC8032]Josefsson,S.和I.Liusvaara,“爱德华兹曲线数字签名算法(EdDSA)”,RFC 8032,DOI 10.17487/RFC8032,2017年1月<https://www.rfc-editor.org/info/rfc8032>.

[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, <https://www.rfc-editor.org/info/rfc8174>.

[RFC8174]Leiba,B.,“RFC 2119关键词中大写与小写的歧义”,BCP 14,RFC 8174,DOI 10.17487/RFC8174,2017年5月<https://www.rfc-editor.org/info/rfc8174>.

9.2. Informative References
9.2. 资料性引用

[RFC3447] Jonsson, J. and B. Kaliski, "Public-Key Cryptography Standards (PKCS) #1: RSA Cryptography Specifications Version 2.1", RFC 3447, DOI 10.17487/RFC3447, February 2003, <https://www.rfc-editor.org/info/rfc3447>.

[RFC3447]Jonsson,J.和B.Kaliski,“公钥密码标准(PKCS)#1:RSA密码规范版本2.1”,RFC 3447,DOI 10.17487/RFC3447,2003年2月<https://www.rfc-editor.org/info/rfc3447>.

Appendix A. Example of a Signed Message
附录A.签名消息示例

This is a small message with both RSA-SHA256 and Ed25519-SHA256 DKIM signatures. The signatures are independent of each other, so either signature would be valid if the other were not present.

这是一条带有RSA-SHA256和Ed25519-SHA256 DKIM签名的小消息。这些签名相互独立,因此,如果另一个签名不存在,则任何一个签名都是有效的。

A.1. Secret Keys
A.1. 密钥

Ed25519 secret key in base64. This is the secret key from [RFC8032], Section 7.1, Test 1, converted from hex to base64.

base64中的Ed25519密钥。这是[RFC8032]第7.1节测试1中的密钥,从十六进制转换为base64。

nWGxne/9WmC6hEr0kuwsxERJxWl7MmkZcDusAxyuf2A=

nWGxne/9WMC6HER0KWSXERJXWL7MKZCDUSAXYUF2A=

RSA secret key in PEM format.

PEM格式的RSA密钥。

   -----BEGIN RSA PRIVATE KEY-----
   MIICXQIBAAKBgQDkHlOQoBTzWRiGs5V6NpP3idY6Wk08a5qhdR6wy5bdOKb2jLQi
   Y/J16JYi0Qvx/byYzCNb3W91y3FutACDfzwQ/BC/e/8uBsCR+yz1Lxj+PL6lHvqM
   KrM3rG4hstT5QjvHO9PzoxZyVYLzBfO2EeC3Ip3G+2kryOTIKT+l/K4w3QIDAQAB
   AoGAH0cxOhFZDgzXWhDhnAJDw5s4roOXN4OhjiXa8W7Y3rhX3FJqmJSPuC8N9vQm
   6SVbaLAE4SG5mLMueHlh4KXffEpuLEiNp9Ss3O4YfLiQpbRqE7Tm5SxKjvvQoZZe
   zHorimOaChRL2it47iuWxzxSiRMv4c+j70GiWdxXnxe4UoECQQDzJB/0U58W7RZy
   6enGVj2kWF732CoWFZWzi1FicudrBFoy63QwcowpoCazKtvZGMNlPWnC7x/6o8Gc
   uSe0ga2xAkEA8C7PipPm1/1fTRQvj1o/dDmZp243044ZNyxjg+/OPN0oWCbXIGxy
   WvmZbXriOWoSALJTjExEgraHEgnXssuk7QJBALl5ICsYMu6hMxO73gnfNayNgPxd
   WFV6Z7ULnKyV7HSVYF0hgYOHjeYe9gaMtiJYoo0zGN+L3AAtNP9huqkWlzECQE1a
   licIeVlo1e+qJ6Mgqr0Q7Aa7falZ448ccbSFYEPD6oFxiOl9Y9se9iYHZKKfIcst
   o7DUw1/hz2Ck4N5JrgUCQQCyKveNvjzkkd8HjYs0SwM0fPjK16//5qDZ2UiDGnOe
   uEzxBDAr518Z8VFbR41in3W4Y3yCDgQlLlcETrS+zYcL
   -----END RSA PRIVATE KEY-----
        
   -----BEGIN RSA PRIVATE KEY-----
   MIICXQIBAAKBgQDkHlOQoBTzWRiGs5V6NpP3idY6Wk08a5qhdR6wy5bdOKb2jLQi
   Y/J16JYi0Qvx/byYzCNb3W91y3FutACDfzwQ/BC/e/8uBsCR+yz1Lxj+PL6lHvqM
   KrM3rG4hstT5QjvHO9PzoxZyVYLzBfO2EeC3Ip3G+2kryOTIKT+l/K4w3QIDAQAB
   AoGAH0cxOhFZDgzXWhDhnAJDw5s4roOXN4OhjiXa8W7Y3rhX3FJqmJSPuC8N9vQm
   6SVbaLAE4SG5mLMueHlh4KXffEpuLEiNp9Ss3O4YfLiQpbRqE7Tm5SxKjvvQoZZe
   zHorimOaChRL2it47iuWxzxSiRMv4c+j70GiWdxXnxe4UoECQQDzJB/0U58W7RZy
   6enGVj2kWF732CoWFZWzi1FicudrBFoy63QwcowpoCazKtvZGMNlPWnC7x/6o8Gc
   uSe0ga2xAkEA8C7PipPm1/1fTRQvj1o/dDmZp243044ZNyxjg+/OPN0oWCbXIGxy
   WvmZbXriOWoSALJTjExEgraHEgnXssuk7QJBALl5ICsYMu6hMxO73gnfNayNgPxd
   WFV6Z7ULnKyV7HSVYF0hgYOHjeYe9gaMtiJYoo0zGN+L3AAtNP9huqkWlzECQE1a
   licIeVlo1e+qJ6Mgqr0Q7Aa7falZ448ccbSFYEPD6oFxiOl9Y9se9iYHZKKfIcst
   o7DUw1/hz2Ck4N5JrgUCQQCyKveNvjzkkd8HjYs0SwM0fPjK16//5qDZ2UiDGnOe
   uEzxBDAr518Z8VFbR41in3W4Y3yCDgQlLlcETrS+zYcL
   -----END RSA PRIVATE KEY-----
        
A.2. Public Key DNS Records
A.2. 公钥DNS记录

The public key p= value in the first record is the public key from [RFC8032], Section 7.1, Test 1, converted from hex to base64.

第一条记录中的公钥p=值是[RFC8032]第7.1节测试1中的公钥,从十六进制转换为base64。

brisbane._domainkey.football.example.com. IN TXT (
 "v=DKIM1; k=ed25519; p=11qYAYKxCrfVS/7TyWQHOg7hcvPapiMlrwIaaPcHURo=")
        
brisbane._domainkey.football.example.com. IN TXT (
 "v=DKIM1; k=ed25519; p=11qYAYKxCrfVS/7TyWQHOg7hcvPapiMlrwIaaPcHURo=")
        
test._domainkey.football.example.com. IN TXT (
 "v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDkHlOQoBTzWR"
 "iGs5V6NpP3idY6Wk08a5qhdR6wy5bdOKb2jLQiY/J16JYi0Qvx/byYzCNb3W91y3FutAC"
 "DfzwQ/BC/e/8uBsCR+yz1Lxj+PL6lHvqMKrM3rG4hstT5QjvHO9PzoxZyVYLzBfO2EeC3"
 "Ip3G+2kryOTIKT+l/K4w3QIDAQAB")
        
test._domainkey.football.example.com. IN TXT (
 "v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDkHlOQoBTzWR"
 "iGs5V6NpP3idY6Wk08a5qhdR6wy5bdOKb2jLQiY/J16JYi0Qvx/byYzCNb3W91y3FutAC"
 "DfzwQ/BC/e/8uBsCR+yz1Lxj+PL6lHvqMKrM3rG4hstT5QjvHO9PzoxZyVYLzBfO2EeC3"
 "Ip3G+2kryOTIKT+l/K4w3QIDAQAB")
        
A.3. Signed Message
A.3. 签名信息

The text in each line of the message starts at the first position except for the continuation lines on the DKIM-Signature header fields, which start with a single space. A blank line follows the "Joe." line.

消息每行中的文本从第一个位置开始,DKIM签名头字段上的续行除外,续行以单个空格开始。“Joe.”行后面有一个空行。

   DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed;
    d=football.example.com; i=@football.example.com;
    q=dns/txt; s=brisbane; t=1528637909; h=from : to :
    subject : date : message-id : from : subject : date;
    bh=2jUSOH9NhtVGCQWNr9BrIAPreKQjO6Sn7XIkfJVOzv8=;
    b=/gCrinpcQOoIfuHNQIbq4pgh9kyIK3AQUdt9OdqQehSwhEIug4D11Bus
    Fa3bT3FY5OsU7ZbnKELq+eXdp1Q1Dw==
   DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
    d=football.example.com; i=@football.example.com;
    q=dns/txt; s=test; t=1528637909; h=from : to : subject :
    date : message-id : from : subject : date;
    bh=2jUSOH9NhtVGCQWNr9BrIAPreKQjO6Sn7XIkfJVOzv8=;
    b=F45dVWDfMbQDGHJFlXUNB2HKfbCeLRyhDXgFpEL8GwpsRe0IeIixNTe3
    DhCVlUrSjV4BwcVcOF6+FF3Zo9Rpo1tFOeS9mPYQTnGdaSGsgeefOsk2Jz
    dA+L10TeYt9BgDfQNZtKdN1WO//KgIqXP7OdEFE4LjFYNcUxZQ4FADY+8=
   From: Joe SixPack <joe@football.example.com>
   To: Suzie Q <suzie@shopping.example.net>
   Subject: Is dinner ready?
   Date: Fri, 11 Jul 2003 21:00:37 -0700 (PDT)
   Message-ID: <20030712040037.46341.5F8J@football.example.com>
        
   DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed;
    d=football.example.com; i=@football.example.com;
    q=dns/txt; s=brisbane; t=1528637909; h=from : to :
    subject : date : message-id : from : subject : date;
    bh=2jUSOH9NhtVGCQWNr9BrIAPreKQjO6Sn7XIkfJVOzv8=;
    b=/gCrinpcQOoIfuHNQIbq4pgh9kyIK3AQUdt9OdqQehSwhEIug4D11Bus
    Fa3bT3FY5OsU7ZbnKELq+eXdp1Q1Dw==
   DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
    d=football.example.com; i=@football.example.com;
    q=dns/txt; s=test; t=1528637909; h=from : to : subject :
    date : message-id : from : subject : date;
    bh=2jUSOH9NhtVGCQWNr9BrIAPreKQjO6Sn7XIkfJVOzv8=;
    b=F45dVWDfMbQDGHJFlXUNB2HKfbCeLRyhDXgFpEL8GwpsRe0IeIixNTe3
    DhCVlUrSjV4BwcVcOF6+FF3Zo9Rpo1tFOeS9mPYQTnGdaSGsgeefOsk2Jz
    dA+L10TeYt9BgDfQNZtKdN1WO//KgIqXP7OdEFE4LjFYNcUxZQ4FADY+8=
   From: Joe SixPack <joe@football.example.com>
   To: Suzie Q <suzie@shopping.example.net>
   Subject: Is dinner ready?
   Date: Fri, 11 Jul 2003 21:00:37 -0700 (PDT)
   Message-ID: <20030712040037.46341.5F8J@football.example.com>
        

Hi.

你好

We lost the game. Are you hungry yet?

我们输了比赛。你饿了吗?

Joe.

乔。

Author's Address

作者地址

John Levine Taughannock Networks PO Box 727 Trumansburg, NY 14886 United States of America

John Levine Taughannock Networks美国纽约州杜鲁曼斯堡727号邮政信箱14886

   Phone: +883.5100.01196712
   Email: standards@taugh.com
        
   Phone: +883.5100.01196712
   Email: standards@taugh.com