Common Authentication Technology Next Generation B. Williams Internet Draft Independent Intended status: Standard September 26, 2017 Expires: March 2018 Open Password Automation Recipe (OPAR) Protocol draft-bwilliams-kitten-opar-00.txt Abstract This document introduces the Open Password Automation Recipe (OPAR) Protocol, a suggested format for providing instructions to password managers programmatically that defines the valid construction of a password. With password managers becoming integrated into browsers, websites should be able to describe the elements of an acceptable password programmatically so password management plugins can read and automatically generate the best option. Without this, manual intervention by the user is required when the password is too long, contains invalid characters, or does not meet complexity requirements. Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. This document may not be modified, and derivative works of it may not be created, except to publish it as an RFC and to translate it into languages other than English. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html This Internet-Draft will expire on March 26, 2018. Williams Expires March 26, 2018 [Page 1] Internet-Draft Open Password Automation Recipe Protocol September 2017 Copyright Notice Copyright (c) 2017 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://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. Table of Contents 1. Introduction......................................................3 2. Conventions used in this document.................................4 3. Construction of OPAR Policy.......................................4 3.1. OPAR_Policy - OPAR Version 1..............................4 3.1.1. "min_length" - Integer value.........................5 3.1.2. "max_length" - Integer value.........................5 3.1.3. "numbers" - Object...................................5 3.1.3.1. "allowed" - Boolean value.......................5 3.1.3.2. "minimum" - Integer value.......................5 3.1.4. "lowercase" - Object.................................5 3.1.4.1. "allowed" - Boolean value.......................5 3.1.4.2. "minimum" - Integer value.......................5 3.1.5. "uppercase" - Object.................................6 3.1.5.1. "allowed" - Boolean value.......................6 3.1.5.2. "minimum" - Integer value.......................6 3.1.6. "special_characters" - Object........................6 3.1.6.1. "allowed" - Boolean value.......................6 3.1.6.2. "valid_characters" - String value...............6 3.1.6.3. "minimum" - Integer value.......................6 3.1.7. "wide_characters" - Object...........................6 3.1.7.1. "allowed" - Boolean value.......................7 3.1.7.2. "minimum" - Integer value.......................7 3.1.8. "include_extended_ascii" - Boolean value.............7 3.2. Examples..................................................7 3.2.1. Password Recipe Example 1............................7 3.2.2. Password Recipe Example 1............................8 4. Security Considerations..........................................10 Williams Expires March 26, 2018 [Page 2] Internet-Draft Open Password Automation Recipe Protocol September 2017 5. IANA Considerations..............................................10 6. Conclusions......................................................10 7. References.......................................................10 7.1. Normative References.....................................10 7.2. Informative References...................................10 8. Acknowledgments..................................................11 1. Introduction Password managers are becoming the norm as both Apple and Google have embedded them into their operating systems and browsers. The goal addressed by password managers is to enable users to use different username/password combinations on every site they visit, while locally storing all of those items encrypted. When a user visits a site, stored passwords are automatically presented for authentication. Password reuse is a known vulnerability in authentication systems and can lead to identity theft[2]. With several available password management systems such as 1Password, LastPass, and the Apple Keychain, a standardized, programmatic way to read the password policy of a website would further automate these applications. Password managers embed functionality into popular browsers to suggest secure passwords and manage them across devices. The challenge with password generation is that not all sites use the same requirements to create a password, and individuals will often not maximize the strength of a new password as they take the default suggested value. As an example, a site that suggests a password of 8-20 characters might receive "9ay-mgr-3PO-iaa" from a password manager, five characters short of the maximum. In addition, the site may not permit hyphens in passwords, yet still require a special character. Users would need to randomly create one to comply with the standard. This document proposes the Open Password Automation Recipe (OPAR) Protocol as a way to define valid password recipes for password managers while improving user experience. OPAR is a simple protocol that can be implemented on any page where password generation is required (such as a sign up or change password page) to inform password managers of the acceptable format for a valid password. Then the password manager can suggest and fill in the strongest possible password without requiring user intervention to tweak the recipe. Implementing and Executing the OPAR Protocol: Williams Expires March 26, 2018 [Page 3] Internet-Draft Open Password Automation Recipe Protocol September 2017 1. Site operator adds markup or JSON in the format below to pages requiring password automation. 2. Password manager interprets format to automatically suggest a password that maximizes password strength according to the recipe. 3. Submit the password while storing credentials inside the password manager. 2. Conventions used in this document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119[1]. In this document, these words will appear with that interpretation only when in ALL CAPS. Lower case uses of these words are not to be interpreted as carrying significance described in RFC 2119. In this document, the characters ">>" preceding an indented line(s) indicates a statement using the key words listed above. This convention aids reviewers in quickly identifying or finding the portions of this RFC covered by these keywords. 3. Construction of OPAR Policy This section defines the construction of a JSON object that declares the options in the OPAR protocol. 3.1. OPAR_Policy - OPAR Version 1 The JSON object that stores the OPAR values MUST be named OPAR_Policy. This object SHOULD be included only on the new password and change password pages. The first element in the JSON object MUST be named "version" with an integer value corresponding to the value of the protocol. The only value that is acceptable at this time is 1, but future versions of the protocol may add additional features. All of the elements below MUST be included in the OPAR object definition to be considered a valid implementation of version 1 of the protocol. Some elements, however, MAY be listed at 0 (say for example if there is no minimum number of special characters), but the element MUST be present in the object. Williams Expires March 26, 2018 [Page 4] Internet-Draft Open Password Automation Recipe Protocol September 2017 The following sub-sections describe the remainder of the OPAR record options available in version 1 of the OPAR protocol. 3.1.1. "min_length" - Integer value Password recipes require a minimum length to be valid. The integer value in this field represents the absolute minimum number of characters required for a valid password. 3.1.2. "max_length" - Integer value The integer value here should be the maximum number of characters allowed. Password managers should focus on this value and elect to fill every available position in the password with a character. 3.1.3. "numbers" - Object The numbers object will define the options for numbers in the password recipe. 3.1.3.1. "allowed" - Boolean value If numbers are allowed, set the value to true. If not, set the value to false. 3.1.3.2. "minimum" - Integer value If numbers are required, enter the minimum amount of single digit integers that will constitute a valid password. If numbers are allowed but not required, set this value to 0. 3.1.4. "lowercase" - Object The lowercase object will define the options for lowercase letters in the password recipe. 3.1.4.1. "allowed" - Boolean value If lowercase letters are allowed, set the value to true. If not, set the value to false. 3.1.4.2. "minimum" - Integer value If lowercase letters are required, enter the minimum amount of single digit lowercase characters that will constitute a valid password. If lowercase letters are allowed but not required, set this value to 0. Williams Expires March 26, 2018 [Page 5] Internet-Draft Open Password Automation Recipe Protocol September 2017 3.1.5. "uppercase" - Object The uppercase object will define the options for uppercase letters in the password recipe. 3.1.5.1. "allowed" - Boolean value If uppercase letters are allowed, set the value to true. If not, set the value to false. 3.1.5.2. "minimum" - Integer value If uppercase letters are required, enter the minimum amount of single digit uppercase characters that will constitute a valid password. If uppercase letters are allowed but not required, set this value to 0. 3.1.6. "special_characters" - Object The special_characters object will define the options for special characters in the password recipe. 3.1.6.1. "allowed" - Boolean value If special characters are allowed, set the value to true. If not, set the value to false. 3.1.6.2. "valid_characters" - String value A single string value that contains one of every special character. This should be represented as a set of valid special characters that make up a password. Only include special characters that may be used in the password. Remember to escape double quotes if that character is allowed. 3.1.6.3. "minimum" - Integer value If special characters are required, enter the minimum amount of single digit special characters that will constitute a valid password. If special characters are allowed but not required, set this value to 0. 3.1.7. "wide_characters" - Object Some locales may require or desire the use of so called wide or multibyte characters. This object will define the options for wide characters in the password recipe. Williams Expires March 26, 2018 [Page 6] Internet-Draft Open Password Automation Recipe Protocol September 2017 3.1.7.1. "allowed" - Boolean value If wide characters are allowed, set the value to true. If not, set the value to false. 3.1.7.2. "minimum" - Integer value If wide characters are required, enter the minimum amount of single digit wide characters that will constitute a valid password. If wide characters are allowed but not required, set this value to 0. 3.1.8. "include_extended_ascii" - Boolean value Some locales may leverage characters from the extended ASCII character set, such as Cyrillic, accented Western characters, and Greek characters. If you want to allow these characters, set this value to true. There are no minimums here as these would simply extend the uppercase and lowercase character sets. 3.2. Examples The following sections provide two examples of JSON objects that define a password recipe. 3.2.1. Password Recipe Example 1 The following OPAR password recipe defines a valid password that must be at least 8 characters, but no more than 20, with numbers, lowercase letters, and uppercase letters all allowed (minimum two of each), and only these special characters allowed (+ - _ ( ) * & ^ % $ # @ ! ?), minimum 2. No wide characters are allowed, but the extended ASCII set is permitted. { "version":1, "min_length":8, "max_length":20, "numbers":{ "allowed": true, "minimum": 2 Williams Expires March 26, 2018 [Page 7] Internet-Draft Open Password Automation Recipe Protocol September 2017 }, "lowercase":{ "allowed": true, "minimum": 2 }, "uppercase":{ "allowed": true, "minimum": 2 }, "special_characters":{ "allowed": true, "valid_characters": "+-_()*&^%$#@!?", "minimum": 2 }, "wide_characters":{ "allowed": false, "minimum": 0 }, "include_extended_ascii": true } 3.2.2. Password Recipe Example 1 The following OPAR password recipe defines a valid password that must be at least 6 characters, but no more than 12, with numbers, lowercase letters, and uppercase letters only allowed (minimum one of each). No special characters, extended ASCII, or wide characters are permitted. Williams Expires March 26, 2018 [Page 8] Internet-Draft Open Password Automation Recipe Protocol September 2017 { "version":1, "min_length":6, "max_length":12, "numbers":{ "allowed": true, "minimum": 1 }, "lowercase":{ "allowed": true, "minimum": 1 }, "uppercase":{ "allowed": true, "minimum": 1 }, "special_characters":{ "allowed": false, "valid_characters": null, "minimum": 0 }, "wide_characters":{ "allowed": false, "minimum": 0 Williams Expires March 26, 2018 [Page 9] Internet-Draft Open Password Automation Recipe Protocol September 2017 }, "include_extended_ascii": false } 4. Security Considerations In order for the recipes to be effective, site managers must ensure that the recipe promotes the maximum password complexity possible. Ideally, two things should happen. Site managers should review existing password storage capabilities to maximize the strength of new passwords, and recipes should mirror the instructions given to users in English on how to construct a secure password. Password managers should focus on the largest effective strength of password based on the maximum allowed character positions given the defined acceptable keyspace (allowed characters) to provide maximum password effectiveness[3]. 5. IANA Considerations No IANA considerations required. 6. Conclusions The OPAR Protocol is designed to improve automation and usability of password managers used by individuals at large. Through this additional automation, users will not have to fight password managers and may more readily adopt them as their user experience improves. 7. References 7.1. Normative References [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. 7.2. Informative References [2] Gaw, S., & Felten, E. W. (2006, July). Password management strategies for online accounts. In Proceedings of the second symposium on Usable privacy and security (pp. 44-55). ACM. Williams Expires March 26, 2018 [Page 10] Internet-Draft Open Password Automation Recipe Protocol September 2017 [3] O'Gorman, L. (2003). Comparing passwords, tokens, and biometrics for user authentication. Proceedings of the IEEE, 91(12), 2021-2040. 8. Acknowledgments Special thanks to Matt Springfield for being a sounding board. This document was prepared using 2-Word-v2.0.template.dot. Williams Expires March 26, 2018 [Page 11] Internet-Draft Open Password Automation Recipe Protocol September 2017 Authors' Addresses Branden Williams Independent 2450 Lakeside Parkway Suite 150-1026 Flower Mound TX 75022 Email: ietf@brandenwilliams.com Williams Expires March 26, 2018 [Page 12]