Add xep-sasl-cb-types

Flowdalic · May 20, 2020 · c0af4ae · c0af4ae
1 parent b9bbbcf
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diff --git a/xep-sasl-cb-types/Makefile b/xep-sasl-cb-types/Makefile
@@ -0,0 +1,77 @@
+.PHONY: all clean
+
+# Finde the path to the Makefile, and the path to the directory of the
+# Makefile. Credits to http://stackoverflow.com/a/18137056/194894
+MKFILE_PATH := $(abspath $(lastword $(MAKEFILE_LIST)))
+MKFILE_DIR := $(notdir $(patsubst %/,%,$(dir $(MKFILE_PATH))))
+XEP := $(shell basename $(MKFILE_DIR))
+XEP_XML := $(XEP).xml
+FROM_XMPP_GIT := xep.xsl xep.dtd xep.ent xmpp.css prettify.css prettify.js
+
+ifneq ($(wildcard xep-official.xml),)
+OFFICIAL_XEP_FOUND := true
+else
+OFFICIAL_XEP_FOUND := false
+endif
+
+ifeq ($(OFFICIAL_XEP_FOUND), true)
+all: xep-official.html xml-colordiff.html
+
+XML_DIFF_PREREQUISITES := $(XEP_XML) xep-official.xml
+COLORDIFF_PIPE := wdiff -n $(XML_DIFF_PREREQUISITES) |colordiff
+.PHONY: xml-colordiff
+xml-colordiff:
+	$(COLORDIFF_PIPE) |less -R
+
+xml-colordiff.html: $(XML_DIFF_PREREQUISITES)
+	$(COLORDIFF_PIPE) |aha > $@
+endif
+
+ifeq (,$(shell which htmldiff 2> /dev/null))
+HTMLDIFF_BINARY_AVAILABLE := false
+else
+HTMLDIFF_BINARY_AVAILABLE := true
+endif
+
+DIFF_HTML := diff.html diff-side-by-side.html
+ifeq (true, $(and $(findstring true, $(HTMLDIFF_BINARY_AVAILABLE)), $(findstring true, $(OFFICIAL_XEP_FOUND))))
+all: $(DIFF_HTML)
+endif
+
+all: $(XEP).html
+
+xep.xsl: ../xsf-xeps/xep.xsl
+	cp $^ $@
+
+xep.dtd: ../xsf-xeps/xep.dtd
+	cp $^ $@
+
+xep.ent: ../xsf-xeps/xep.ent
+	cp $^ $@
+
+xmpp.css: ../xsf-xeps/xmpp.css
+	cp $^ $@
+
+prettify.css: ../xsf-xeps/prettify.css
+	cp $^ $@
+
+prettify.js: ../xsf-xeps/prettify.js
+	cp $^ $@
+
+%.html: %.xml $(FROM_XMPP_GIT)
+	xsltproc $^ --output $@
+
+COMMON_DIFF_PREREQUISITES := xep-official.html $(XEP).html
+
+diff.html: $(COMMON_DIFF_PREREQUISITES)
+	htmldiff -a $^ > $@
+
+diff-side-by-side.html: $(COMMON_DIFF_PREREQUISITES)
+	htmldiff -a -s $^ > $@
+
+clean:
+	rm -f $(XEP).html
+	rm -f $(FROM_XMPP_GIT)
+	rm -f $(DIFF_HTML)
+	rm -f xep-official.html
+	rm -f xml-colordiff.html
diff --git a/xep-sasl-cb-types/xep-sasl-cb-types.xml b/xep-sasl-cb-types/xep-sasl-cb-types.xml
@@ -0,0 +1,111 @@
+<?xml version='1.0' encoding='UTF-8'?>
+<!DOCTYPE xep SYSTEM 'xep.dtd' [
+  <!ENTITY rfc5056 "<span class='ref'><link url='http://tools.ietf.org/html/rfc5056'>RFC 5056</link></span> <note>RFC 5056:  On the Use of Channel Bindings to Secure Channels &lt;<link url='http://tools.ietf.org/html/rfc5056'>http://tools.ietf.org/html/rfc5056</link>&gt;.</note>" >
+  <!ENTITY iana-cb-types "<span class='ref'><link url='https://www.iana.org/assignments/channel-binding-types/channel-binding-types.xhtml'>IANA Channel-Binding Types Registry</link></span> <note>IANA Channel-Binding Types Registry &lt;<link url='https://www.iana.org/assignments/channel-binding-types/channel-binding-types.xhtml'>https://www.iana.org/assignments/channel-binding-types/channel-binding-types.xhtml</link>&gt;.</note>" >
+  <!ENTITY % ents SYSTEM 'xep.ent'>
+%ents;
+]>
+<?xml-stylesheet type='text/xsl' href='xep.xsl'?>
+<xep>
+<header>
+  <title>SASL Channel-Binding Type Capability</title>
+  <abstract>This specification provides an example of the format for XMPP Extension Protocols (XEPs).</abstract>
+  &LEGALNOTICE;
+  <number>xxxx</number>
+  <status>ProtoXEP</status>
+  <type>Standards Track</type>
+  <sig>Standards</sig>
+  <approver>Council</approver>
+  <dependencies>
+    <spec>XMPP Core</spec>
+  </dependencies>
+  <supersedes/>
+  <supersededby/>
+  <shortname>sasl-cb-types</shortname>
+  &flow;
+  <revision>
+    <version>0.0.1</version>
+    <date>2020-05-20</date>
+    <initials>fs</initials>
+    <remark><p>First draft.</p></remark>
+  </revision>
+</header>
+<section1 topic='Introduction' anchor='intro'>
+
+  <p>SASL channel-binding is a technique to increase the security of
+  connections (&rfc5056;). Unfortunately, the SASL profile specified
+  in &rfc6120; lacks a method for the server to announce its supported
+  channel-binding types. This hinders the adoption of channel-binding,
+  especially since the error protocol to execute after a client
+  requested a channel-binding type unsupported by the server is
+  basically unspecified.</p>
+
+  <p>Hence the extension defined herein fills the gap left by
+  &rfc6120; by allowing the server the announce its supported
+  channel-binding types.</p>
+
+</section1>
+
+<section1 topic='Announcing the SASL Channel-Binding Type Capability' anchor='sasl-cb-type'>
+
+  <p>This specification extends the SASL 'mechanism' element,
+  qualified by the 'urn:ietf:params:xml:ns:xmpp-sasl' namespace, by an
+  optional attribute named 'sasl-channel-binding'. This element
+  contains one or more 'channel-binding' elements, of which each MUST
+  have an attribute with the name 'type'. The value of the 'type'
+  attribute SHOULD be the "Channel-binding unique prefix" of a
+  channel-binding type registered with the &iana-cb-types;.</p>
+
+  <p>An entity declares that it supports particular channel-binding
+  types, by listing the channel-binding types via the
+  'sasl-channel-binding' element defined herein.</p>
+
+  <example caption='Example &gt;mechanisms/&lt; stream feature with SASL Channel-Binding Type Capability.'><![CDATA[
+<stream:features>
+  <mechanisms xmlns='urn:ietf:params:xml:ns:xmpp-sasl'>
+    <mechanism>EXTERNAL</mechanism>
+    <mechanism>SCRAM-SHA-1-PLUS</mechanism>
+    <mechanism>PLAIN</mechanism>
+    <sasl-channel-binding>
+      <channel-binding type='tls-server-end-point'/>
+      <channel-binding type='tls-exporter'/>
+    </sasl-channel-binding>
+  </mechanisms>
+</stream:features>]]></example>
+
+</section1>
+
+<section1 topic='Security Considerations' anchor='security'>
+
+  <p>The author belives that this document itself does not yield any
+  new security considerations.<note>Hopefully somebody will correct him, in
+  case he is wrong.</note></p>
+
+</section1>
+
+<section1 topic='IANA Considerations' anchor='iana'>
+
+  <p>This document requires no interaction with &IANA;.</p>
+
+</section1>
+
+<section1 topic='XMPP Registrar Considerations' anchor='registrar'>
+
+  <p>This document requires no interaction with the XMPP registrar.</p>
+
+</section1>
+
+<section1 topic='XML Schema' anchor='schema'>
+
+  <p>TODO: Add if the XEP is scheduled for the state after 'experimental'.</p>
+
+</section1>
+
+<section1 topic='Acknowledgements' anchor='acknowledgements'>
+
+  <p>Thanks to Sam Whited for the discussion about the underlying
+  issue and incentivizing me to come up with this extension.</p>
+
+</section1>
+
+</xep>