Network Working Group S. Leonard Internet-Draft Penango, Inc. Updates: 5234 (if approved) October 8, 2015 Intended Status: Standards Track Expires: April 10, 2016 Comprehensive Core Rules for ABNF draft-seantek-abnf-more-core-rules-02 Abstract This document extends the base definition of ABNF (Augmented Backus- Naur Form) to include comprehensive support for certain symbols, namely the C0 control characters in ASCII. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at http://datatracker.ietf.org/drafts/current/. 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." This Internet-Draft will expire on April 10, 2016. Copyright Notice Copyright (c) 2015 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. Leonard Standards Track [Page 1] Internet-Draft More Core Rules October 2015 1. Comprehensive Core Rule Update Augmented Backus-Naur Form (ABNF) [RFC5234] is a formal syntax that is popular among many Internet specifications. Many Internet documents employ this syntax along with the Core Rules defined in Appendix B.1 of [RFC5234]. However, the Core Rules do not specify many symbols in the ASCII range that are also needed by these relying documents, forcing document authors to define them as local rules. Sometimes different documents define these common symbols in different ways, resulting in confusion or incompatibility when the rules are misread or are combined with other sets of rules. This document extends [RFC5234] to include comprehensive support for certain symbols, namely the C0 control characters in [ASCII86], which for purposes of this document is equivalent to [RFC0020]. Appendix A of this document is meant as a drop-in replacement for Appendix B.1 of [RFC5234]. I.e., these Core Rules are no more or less useful or normative than those in [RFC5234]. Future document authors should use these rules, and should not attempt to redefine or augment them (except for backwards compatibility with prior documents). 2. IANA Considerations This document implies no IANA considerations. 3. Security Considerations Security is truly believed to be irrelevant to this document. 4. Normative References [ASCII86] American National Standards Institute, "Coded Character Set -- 7-bit American Standard Code for Information Interchange", ANSI X3.4, 1986. [RFC0020] Cerf, V., "ASCII format for network interchange", RFC 20, October 1969. [RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", STD 68, RFC 5234, January 2008. Leonard Standards Track [Page 2] Internet-Draft More Core Rules October 2015 Appendix A. Comprehensive Core Rules Certain basic rules are in uppercase, such as SP, HTAB, CRLF, DIGIT, ALPHA, etc. ALPHA = %x41-5A / %x61-7A ; A-Z / a-z BIT = "0" / "1" CHAR = %x01-7F ; any 7-bit US-ASCII character, ; excluding NUL CR = %x0D ; carriage return CRLF = CR LF ; Internet standard newline CTL = %x00-1F / %x7F ; controls DIGIT = %x30-39 ; 0-9 DQUOTE = %x22 ; " (Double Quote) HEXDIG = DIGIT / "A" / "B" / "C" / "D" / "E" / "F" HTAB = %x09 ; horizontal tab LF = %x0A ; linefeed LWSP = *(WSP / CRLF WSP) ; Use of this linear-white-space rule ; permits lines containing only white ; space that are no longer legal in ; mail headers and have caused ; interoperability problems in other ; contexts. ; Do not use when defining mail ; headers and use with caution in ; other contexts. OCTET = %x00-FF Leonard Standards Track [Page 3] Internet-Draft More Core Rules October 2015 ; 8 bits of data SP = %x20 VCHAR = %x21-7E ; visible (printing) characters WSP = SP / HTAB ; white space NUL = %d0 SOH = %d1 STX = %d2 ETX = %d3 EOT = %d4 ENQ = %d5 ACK = %d6 BEL = %d7 BS = %d8 HT = %d9 ; also defined as HTAB VT = %d11 FF = %d12 ; (literally used in every RFC) SO = %d14 SI = %d15 DLE = %d16 DC1 = %d17 DC2 = %d18 DC3 = %d19 DC4 = %d20 NAK = %d21 SYN = %d22 ETB = %d23 CAN = %d24 EM = %d25 SUB = %d26 ESC = %d27 FS = %d28 GS = %d29 RS = %d30 US = %d31 DEL = %d127 Leonard Standards Track [Page 4] Internet-Draft More Core Rules October 2015 Author's Address Sean Leonard Penango, Inc. 5900 Wilshire Boulevard 21st Floor Los Angeles, CA 90036 USA EMail: dev+ietf@seantek.com URI: http://www.penango.com/ Leonard Standards Track [Page 5]