Network Working Group P. Hoffman
Internet-Draft ICANN
Intended status: Informational J. Hildebrand
Expires: January 1, 2017 Cisco
June 30, 2016
RFC v3 Prep Tool Description
draft-iab-rfcv3-preptool-02
Abstract
This document describes some aspects of the "prep tool" that is
expected to be created when the new RFC v3 specification is deployed.
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 January 1, 2017.
Copyright Notice
Copyright (c) 2016 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.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. v3 Prep Tool Usage Scenarios . . . . . . . . . . . . . . . . 4
3. Internet-Draft Submission . . . . . . . . . . . . . . . . . . 4
4. Canonical RFC Preparation . . . . . . . . . . . . . . . . . . 5
5. What the v3 Prep Tool Does . . . . . . . . . . . . . . . . . 5
5.1. XML Sanitization . . . . . . . . . . . . . . . . . . . . 5
5.1.1. XInclude Processing . . . . . . . . . . . . . . . . . 6
5.1.2. DTD Removal . . . . . . . . . . . . . . . . . . . . . 6
5.1.3. Processing Instruction Removal . . . . . . . . . . . 6
5.1.4. Validity Check . . . . . . . . . . . . . . . . . . . 6
5.1.5. Check "anchor" . . . . . . . . . . . . . . . . . . . 6
5.2. Defaults . . . . . . . . . . . . . . . . . . . . . . . . 6
5.2.1. "version" Insertion . . . . . . . . . . . . . . . . . 6
5.2.2. "seriesInfo" Insertion . . . . . . . . . . . . . . . 6
5.2.3. <date> Insertion . . . . . . . . . . . . . . . . . . 7
5.2.4. "prepTime" Insertion . . . . . . . . . . . . . . . . 7
5.2.5. <ol> Group "start" Insertion . . . . . . . . . . . . 7
5.2.6. Attribute Default Value Insertion . . . . . . . . . . 7
5.2.7. Section "toc" attribute . . . . . . . . . . . . . . . 7
5.2.8. "removeInRFC" Warning Paragraph . . . . . . . . . . . 8
5.3. Normalization . . . . . . . . . . . . . . . . . . . . . . 8
5.3.1. "month" Attribute . . . . . . . . . . . . . . . . . . 8
5.3.2. ASCII Attribute Processing . . . . . . . . . . . . . 8
5.3.3. "title" Conversion . . . . . . . . . . . . . . . . . 8
5.4. Generation . . . . . . . . . . . . . . . . . . . . . . . 9
5.4.1. "expiresDate" Insertion . . . . . . . . . . . . . . . 9
5.4.2. <boilerplate> Insertion . . . . . . . . . . . . . . . 9
5.4.2.1. Compare <rfc> "submissionType" and <seriesInfo>
"stream" . . . . . . . . . . . . . . . . . . . . 9
5.4.2.2. 'Status of this Memo' Insertion . . . . . . . . . 9
5.4.2.3. Copyright Insertion . . . . . . . . . . . . . . . 9
5.4.3. <reference> "target" Insertion . . . . . . . . . . . 9
5.4.4. <name> Slugification . . . . . . . . . . . . . . . . 10
5.4.5. <reference> Sorting . . . . . . . . . . . . . . . . . 10
5.4.6. "pn" Numbering . . . . . . . . . . . . . . . . . . . 10
5.4.7. <iref> Numbering . . . . . . . . . . . . . . . . . . 10
5.4.8. <xref> processing . . . . . . . . . . . . . . . . . . 11
5.4.8.1. "derivedContent" Insertion (With Content) . . . . 11
5.4.8.2. "derivedContent" Insertion (Without Content) . . 11
5.4.9. <relref> Processing . . . . . . . . . . . . . . . . . 11
5.5. Inclusion . . . . . . . . . . . . . . . . . . . . . . . . 12
5.5.1. <artwork> Processing . . . . . . . . . . . . . . . . 12
5.5.2. <sourcecode> Processing . . . . . . . . . . . . . . . 13
5.6. RFC Production Mode Cleanup . . . . . . . . . . . . . . . 14
5.6.1. <note> Removal . . . . . . . . . . . . . . . . . . . 14
5.6.2. <cref> Removal . . . . . . . . . . . . . . . . . . . 14
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5.6.3. <link> Processing . . . . . . . . . . . . . . . . . . 14
5.6.4. XML Comment Removal . . . . . . . . . . . . . . . . . 15
5.6.5. "xml:base" and "originalSrc" Removal . . . . . . . . 15
5.6.6. Compliance Check . . . . . . . . . . . . . . . . . . 15
5.7. Finalization . . . . . . . . . . . . . . . . . . . . . . 15
5.7.1. "scripts" Insertion . . . . . . . . . . . . . . . . . 15
5.7.2. Pretty-Format . . . . . . . . . . . . . . . . . . . . 15
6. Additional Uses for the Prep Tool . . . . . . . . . . . . . . 15
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
8. Security Considerations . . . . . . . . . . . . . . . . . . . 16
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 16
10. Informative References . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
For the future of the RFC format, the RFC Editor has decided that XML
(using the XML2RFCv3 vocabulary [I-D.iab-xml2rfc]) is the canonical
format, in the sense that it is the data that is the authorized,
recognized, accepted, and archived version of the document. See
[RFC6949] for more detail on this.
Most people will read other formats, such as HTML, PDF, ASCII text,
or other formats of the future, however. In order to ensure each of
these formats is as similar as possible to one another as well as the
canonical XML, there is a desire that the translation from XML into
the other formats will be straightforward syntactic translation. To
make that happen, a good amount of data will need to be in the XML
format that is not there today. That data will be added by a program
called the "prep tool", which will often run as a part of the xml2rfc
process.
This draft specifies the steps that the prep tool will have to take.
As changes to [I-D.iab-xml2rfc] are made, this document will be
updated.
The details (particularly any vocabularies) described in this
document are expected to change based on experience gained in
implementing the RFC Production Center's (RPC) toolset. Revised
documents will be published capturing those changes as the toolset is
completed. Other implementers must not expect those changes to
remain backwards-compatible with the details described in this
document.
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2. v3 Prep Tool Usage Scenarios
The prep tool will have several settings:
o Internet-Draft preparation
o Canonical RFC preparation
There are only a few differences between the two settings. For
example, the boilerplate output will be different, as will the date
output on the front page.
Note that this only describes what the IETF-sponsored prep tool does.
Others might create their own work-alike prep tools for their own
formatting needs. However, an output format developer does not need
to change the prep tool in order to create their own formatter: they
only need to be able to consume prepared text. The IETF-sponsored
prep tool runs in two different modes: "I-D" mode when the tool is
run during Internet-Draft submission and processing, and "RFC
production mode" when the tool is run by the RFC Production Center
while producing an RFC.
This tool is described as if it is a separate tool so that we can
reason about its architectural properties. In actual implementation,
it might be a part of a larger suite of functionality.
3. Internet-Draft Submission
When the IETF draft submission tool accepts v3 XML as an input
format, the submission tool runs the submitted file through the prep
tool. This is called "I-D mode" in this document. If the tool finds
no errors, it keeps two XML files: the submitted file and the prepped
file.
The prepped file provides a record of what a submitter was attesting
to at the time of submission. It represents a self-contained record
of what any external references resolved to at the time of
submission.
The prepped file is used by the IETF formatters to create outputs
such as HTML, PDF, and text (or the tools act in a way
indistinguishable from this). The message sent out by the draft
submission tool includes a link to the original XML as well as the
other outputs, including the prepped XML.
The prepped XML can be used by tools not yet developed to output new
formats that have as similar output as possible to the current IETF
formatters. For example, if the IETF creates a .mobi output renderer
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later, it can run that renderer on all of the prepped XML that has
been saved, ensuring that the content of included external references
and all of the part numbers and boilerplate will be the same as what
was produced by the previous IETF formatters at the time the document
was first uploaded.
4. Canonical RFC Preparation
During AUTH48, the RPC will run the prep tool in canonical RFC
production mode and make the results available to the authors so they
can see what the final output might look like. When the document has
passed AUTH48 review, the RPC runs the prep tool in canonical RFC
production mode one last time, locks down the canonicalized XML, runs
the formatters for the publication formats, and publishes all of
those.
This document assumes that the prep tool will be used in the
following manner by the RPC; they may use something different, or
with different configuration.
Similarly to I-D's, the prepped XML can be used later to re-render
the output formats, or to generate new formats.
5. What the v3 Prep Tool Does
The steps listed here are in order of processing. In all cases where
the prep tool would "add" an attribute or element, if that attribute
or element already exists, the prep tool will check that the
attribute or element has valid values. If the value is incorrect,
the prep tool will warn with the old and new values, then replace the
incorrect value with the new value.
Currently, the IETF uses a tool called "idnits" to check text input
to the Internet-Drafts publishing process. idnits indicates if it
encountered any errors, and also provide text with all of the
warnings and errors in a human-readable form. The prep tool should
probably check for as many of these errors and warnings as possible
when it is processing the XML input. For the moment, tooling might
run idnts on the text output from the prepared XML. The list below
contains some of those errors and warnings, but the deployed version
of the prep tool may contain additional steps to include more or the
checks from idnits.
5.1. XML Sanitization
These steps will ensure that the input document is properly
formatted, and that all XML processing has been performed.
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5.1.1. XInclude Processing
Process all <x:include> elements. Note: <x:include>d XML may include
more <x:include>s (with relative references resolved against the base
URI potentially modified by a previously inserted xml:base
attribute). The tool may be configurable with a limit on the depth
of recursion.
5.1.2. DTD Removal
Fully process any Document Type Definitions (DTDs) in the input
document, then remove the DTD. At a minimum, this entails processing
the entity references and includes for external files.
5.1.3. Processing Instruction Removal
Remove processing instructions.
5.1.4. Validity Check
Check the input against the RNG in [I-D.iab-xml2rfc]. If the input
is not valid, give an error.
5.1.5. Check "anchor"
Check all elements for "anchor" attributes. If any "anchor"
attribute begins with "s-", "f-", "t-", or "i-", give an error.
5.2. Defaults
These steps will ensure that all default values have been filled in
to the XML, in case the defaults change at a later date. Steps in
this section will not overwrite existing values in the input file.
5.2.1. "version" Insertion
If the <rfc> element has a "version" attribute with a value other
than "3", give an error. If the <rfc> element has no "version"
attribute, add one with the value "3".
5.2.2. "seriesInfo" Insertion
If the <front> element of the <rfc> element does not already have a
<seriesInfo> element, add a <seriesInfo> element with the name
attribute based on the mode in which the preptool is running
("Internet-Draft" for Draft mode and "RFC" for RFC production mode)
and a value that is the input filename minus any extension for
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Internet-Drafts, and is a number specified by the RFC Editor for
RFCs.
5.2.3. <date> Insertion
If the <front> element in the <rfc> element does not contain a <date>
element, add it and fill in the "day", "month", and "year" attibutes
from the current date. If the <front> element in the <rfc> element
has a <date> element with "day", "month", and "year" attibutes, but
the date indicated is more than three days in the past or is in the
future, give a warning. If the <front> element in the <rfc> element
has a <date> element with some but not all of the "day", "month", and
"year" attibutes, give an error.
5.2.4. "prepTime" Insertion
If the input document includes a "prepTime" attribute of <rfc>, exit
with an error.
Fill in the "prepTime" attribute of <rfc> with the current datetime.
5.2.5. <ol> Group "start" Insertion
Add a "start" attribute to every <ol> element containing a group that
does not already have a start.
5.2.6. Attribute Default Value Insertion
Fill in any default values for attributes on elements, except
"keepWithNext" and "keepWithPrevious" of <t>, and "toc" of <section>.
Some default values can be found in the Relax NG schema, while others
can be found in the prose describing the elements in
[I-D.iab-xml2rfc]).
5.2.7. Section "toc" attribute
For each <section>, modify the "toc" attribute to be either "include"
or "exclude":
o for sections that have an ancestor of <boilerplate>, use "exclude"
o else for sections that have a descendant that has toc="include",
use "include". If the section has toc="exclude" in the input,
this is an error.
o else for sections that are children of a section with
toc="exclude", use "exclude".
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o else for sections that are deeper than rfc/@tocDepth, use
"exclude"
o else use "include"
5.2.8. "removeInRFC" Warning Paragraph
If in I-D mode, if there is a <note> or <section> element with a
"removeInRFC" attribute that has the value "true", add a paragraph to
the top of the element with the text "This note is to be removed
before publishing as an RFC." or "This section...", unless a
paragraph consisting of that exact text already exists.
5.3. Normalization
These steps will ensure that ideas that can be expressed in multiple
different ways in the input document are only found in one way in the
prepared document.
5.3.1. "month" Attribute
Normalize the values of "month" attributes in all <date> elements in
<front> elements in <rfc> elements to numeric values.
5.3.2. ASCII Attribute Processing
In every <email>, <organization>, <street>, <city>, <region>,
<country>, and <code> element, if there is an "ascii" attribute and
the value of that attribute is the same as the content of the
element, remove the "ascii" element and issue a warning about the
removal.
In every <author> element, if there is an "asciiFullname",
"asciiInitials", or "asciiSurname" attribute, check the content of
that element against its matching "fullname", "initials", or
"surname" element (respectively). If the two are the same, remove
the "ascii*" elelement and issue a warning about the removal.
5.3.3. "title" Conversion
For every <section>, <note>, <figure>, <references>, and <texttable>
element that has a (deprecated) "title" attribute, remove the "title"
attribute and insert a <name> element with the title from the
attribute.
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5.4. Generation
These steps will generate new content, overriding existing similar
content in the input document. Some of these steps are important
enough that they specify a warning to be generated when the content
being overwritten does not match the new content.
5.4.1. "expiresDate" Insertion
If in I-D mode, fill in "expiresDate" attribute of <rfc> based on the
<date> element of the document's <front> element.
5.4.2. <boilerplate> Insertion
Create a <boilerplate> element if it does not exist. If there are
any children of the <boilerplate> element, produce a warning that
says "Existing boilerplate being removed. Other tools, specifically
the draft submission tool, will treat this condition as an error" and
remove the existing children.
5.4.2.1. Compare <rfc> "submissionType" and <seriesInfo> "stream"
Verify that <rfc> "submissionType" and <seriesInfo> "stream" are the
same if they are both present. If either is missing, add it. Note
that both have a default value of "IETF".
5.4.2.2. 'Status of this Memo' Insertion
Add the "Status of this Memo" section to the <boilerplate> element
with current values. The application will use the "submissionType",
and "consensus" attributes of the <rfc> element, the <workgroup>
element, and the "status" and "stream" attributes of the <seriesInfo>
element, to determine which [I-D.iab-rfc5741bis] boilerplate to
include, as described in Appendix A of [I-D.iab-xml2rfc].
5.4.2.3. Copyright Insertion
Add the "Copyright Notice" section to the <boilerplate> element. The
application will use the "ipr" and "submissionType" attributes of the
<rfc> element and the <date> element to determine which portions and
which version of the TLP to use, as described in A.1 of
[I-D.iab-xml2rfc].
5.4.3. <reference> "target" Insertion
For any <reference> element that does not already have a "target"
attribute, fill the target attribute in if the element has one or
more <seriesinfo> child element(s) and the "name" attribute of the
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<seriesinfo> element is "RFC", "Internet-Draft", or "DOI" or other
value for which it is clear what the "target" should be. The
particular URLs for RFCs, Internet-Drafts, and DOIs for this step
will be specified later by the RFC Editor and the IESG. These URLs
might also be different before and after the v3 format is adopted.
5.4.4. <name> Slugification
Add a "slugifiedName" attribute to each <name> element that does not
contain one; replace the attribute if it contains a value that begins
with "n-".
5.4.5. <reference> Sorting
If the "sortRefs" attribute of the <rfc> element is true, sort the
<reference>s and <referencegroup>s lexically by the value of the
"anchor" attribute, as modified by the "to" attribute of any
<displayreference> element. The RFC Editor needs to determine what
the rules for lexical sorting are. The authors of this document
acknowledge that getting consensus on this will be a difficult task.
5.4.6. "pn" Numbering
Add "pn" attributes for all parts. Parts are:
o <section> in <middle>: pn='s-1.4.2'
o <references>: pn='s-12' or pn='s-12.1'
o <abstract>: pn='s-abstract'
o <note>: pn='s-note-2'
o <section> in <boilerplate>: pn='s-boilerplate-1'
o <table>: pn='t-3'
o <figure>: pn='f-4'
o <artwork>, <aside>, <blockquote>, <dt>, <li>, <sourcecode>, <t>:
pn='p-[section]-[counter]'
5.4.7. <iref> Numbering
In every <iref> element, create a document-unique "pn" attribute.
The value of the "pn" attribute will start with 'i-', and use the
item attribute, the subitem attribute (if it exists), and a counter
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to ensure uniqueness. For example, the first instance of "<iref
item='foo' subitem='bar'>" will get the irefid 'i-foo-bar-1'.
5.4.8. <xref> processing
5.4.8.1. "derivedContent" Insertion (With Content)
For each <xref> element that has content, fill the "derivedContent"
with the element content, having first trimmed the whitespace from
ends of content text. Issue a warning if the "derivedContent"
attribute already exists and has a different value from what was
being filled in.
5.4.8.2. "derivedContent" Insertion (Without Content)
For each <xref> element that does not have content, fill the
"derivedContent" based on the "format" attribute. * For
format='counter', the "derivedContent" is the section, figure, table,
or ordered list number of the element with anchor equal to the xref
target. * For format='default' and the "target" attribute points to
a <reference> or <referencegroup> element, the "derivedContent" is
the value of the "target" attribute (or the "to" attribute of a
<displayreference> element for the targeted <reference>). * For
format='default' and the "target" attribute points to a <section>,
<figure>, or <table>, the "derivedContent" is the name of the thing
pointed to, such as "Section 2.3", "Figure 12", or "Table 4". * For
format='title', if the target is a <reference> element, the
"derivedContent" attribute is the name of the reference, extracted
from the <title> child of the <front> child of the reference. * For
format='title', if the target element has a <name> child element, the
"derivedContent" attribute is the text content of that <name> element
concatenated with the text content of each descendant node of <name>
(that is, stripping out all of the XML markup, leaving only the
text). * For format='title', if the target element does not contain
a <name> child element, the "derivedContent" attribute is the value
of the "target" attribute with no other adornment. Issue a warning
if the "derivedContent" attribute already exists and has a different
value from what was being filled in.
5.4.9. <relref> Processing
If any <relref> element's "target" attribute refers to anything but a
<reference> element, give an error.
For each <relref> element, fill in the "derivedLink" attribute.
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5.5. Inclusion
These steps will include external files into the output document.
5.5.1. <artwork> Processing
1. If an <artwork> element has a "src" attribute where no scheme is
specified, copy the "src" attribute value to the "originalSrc"
attribute, and replace the "src" value with a URI that uses the
"file:" scheme in a path relative to the file being processed.
See Section 8 for warnings about this step. This will likely be
one of the most common authoring approaches.
2. If an <artwork> element has a "src" attribute with a "file:"
scheme, and if processing the URL would cause the processor to
retrieve a file that is not in the same directory, or a
subdirectory, as the file being processed, give an error. If the
"src" has any shellmeta strings (such as "`", "$USER", and so on)
that would be processed , give an error. Replace the "src"
attribute with a URI that uses the "file:" scheme in a path
relative to the file being processed. This rule attempts to
prevent <artwork src='file:///etc/passwd'> and similar security
issues. See Section 8 for warnings about this step.
3. If an <artwork> element has a "src" attribute, and the element
has content, give an error.
4. If an <artwork> element has type='svg' and there is a "src"
attribute, the data needs to be moved into the content of the
<artwork> element.
* If the "src" URI scheme is "data:", fill the content of the
<artwork> element with that data and remove the "src"
attribute.
* If the "src" URI scheme is "file:", "http:", or "https:", fill
the content of the <artwork> element with the resolved XML
from the URI in the "src" attribute. If there is no
"originalSrc" attribute, add an "originalSrc" attribute with
the value of the URI and remove the "src" attribute.
* If the <artwork> element has an "alt" attribute, and the SVG
does not have a <desc> element, add the <desc> element with
the contents of the "alt" attribute.
5. If an <artwork> element has type='binary-art', the data needs to
be in a "src" attribute with a URI scheme of "data:". If the
"src" URI scheme is "file:", "http:", or "https:", resolve the
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URL. Replace the "src" attribute with a "data:" URI, and add an
"originalSrc" attribute with the value of the URI. For the
"http:" and "https:" URI schemes, the mediatype of the "data:"
URI will be the Content-Type of the HTTP response. For the
"file:" URI scheme, the mediatype of the "data:" URI needs to be
guessed with heuristics (this is possibly a bad idea). This also
fails for content that includes binary images but uses a type
other than "binary-art". Note: since this feature can't be used
for RFCs at the moment, this entire feature might be de-
prioritized.
6. If an <artwork> element does not have type='svg' or type='binary-
art' and there is a "src" attribute, the data needs to be moved
into the content of the <artwork> element. Note that this step
assumes that all of the preferred types other than "binary-art"
are text, which is possibly wrong.
* If the "src" URI scheme is "data:", fill the content of the
<artwork> element with the correctly-escaped form of that data
and remove the "src" attribute.
* If the "src" URI scheme is "file:", "http:", or "https:", fill
the content of the <artwork> element with the correctly-
escaped form of the resolved text from the URI in the "src"
attribute. If there is no "originalSrc" attribute, add an
"originalSrc" attribute with the value of the URI and remove
the "src" attribute.
5.5.2. <sourcecode> Processing
1. If an <sourcecode> element has a "src" attribute where no scheme
is specified, copy the "src" attribute value to the "originalSrc"
attribute, and replace the "src" value with a URI that uses the
"file:" scheme in a path relative to the file being processed.
See Section 8 for warnings about this step. This will likely be
one of the most common authoring approaches.
2. If an <sourcecode> element has a "src" attribute with a "file:"
scheme, and if processing the URL would cause the processor to
retrieve a file that is not in the same directory, or a
subdirectory, as the file being processed, give an error. If the
"src" has any shellmeta strings (such as "`", "$USER", and so on)
that would be processed , give an error. Replace the "src"
attribute with a URI that uses the "file:" scheme in a path
relative to the file being processed. This rule attempts to
prevent <sourcecode src='file:///etc/passwd'> and similar
security issues. See Section 8 for warnings about this step.
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3. If an <sourcecode> element has a "src" attribute, and the element
has content, give an error.
4. If an <sourcecode> elementhas a "src" attribute, the data needs
to be moved into the content of the <sourcecode> element.
* If the "src" URI scheme is "data:", fill the content of the
<sourcecode> element with that data and remove the "src"
attribute.
* If the "src" URI scheme is "file:", "http:", or "https:", fill
the content of the <sourcecode> element with the resolved XML
from the URI in the "src" attribute. If there is no
"originalSrc" attribute, add an "originalSrc" attribute with
the value of the URI and remove the "src" attribute.
5.6. RFC Production Mode Cleanup
These steps provide extra cleanup of the output document in RFC
production mode.
5.6.1. <note> Removal
If in RFC production mode, if there is a <note> or <section> element
with a "removeInRFC" attribute that has the value "true", remove the
element.
5.6.2. <cref> Removal
If in RFC production mode, remove all <cref> elements.
5.6.3. <link> Processing
1. If in RFC production mode, remove all <link> elements whose "rel"
attribute has the value "alternate".
2. If in RFC production mode, check if there is a <link> element
with the current ISSN for the RFC series (2070-1721); if not, add
<link rel="item" href="urn:issn:2070-1721">.
3. If in RFC production mode, check if there is a <link> element
with a DOI for this RFC; if not, add one of the form <link
rel="describedBy" href="https://dx.doi.org/10.17487/rfcdd"> where
"dd" is the number of the RFC, such as
"https://dx.doi.org/10.17487/rfc2109". The URI is described in
[RFC7669]. If there was already a <link> element with a DOI for
this RFC, check that the "href" value has the right format.
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4. If in RFC production mode, check if there is a <link> element
with the file name of the Internet-Draft that became this RFC the
form <link rel="convertedFrom"
href="https://datatracker.ietf.org/doc/draft-tttttttttt/">. If
one does not exist, give an error.
5.6.4. XML Comment Removal
If in RFC production mode, remove XML comments.
5.6.5. "xml:base" and "originalSrc" Removal
If in RFC production mode, remove all "xml:base" or "originalSrc"
attributes from all elements.
5.6.6. Compliance Check
If in RFC production mode, ensure that the result is in full
compliance to v3 schema, without any deprecated elements or
attributes, and give an error if any issues are found.
5.7. Finalization
These steps provide the finishing touches on the output document.
5.7.1. "scripts" Insertion
Determine all the characters used in the document, and fill in the
"scripts" attribute for <rfc>.
5.7.2. Pretty-Format
Pretty-format the XML output. (Note: there are many tools that do an
adequate job.)
6. Additional Uses for the Prep Tool
There will be a need for Internet-Draft authors who include files
from their local disk (such as for <artwork src="mydrawing.svg"/>) to
have the contents of those files inlined to their drafts before
submitting them to the Internet-Draft processor. (There is a
possibility that the Internet-Draft processor will allow XML files
and accompanying files to be submitted at the same time, but this
seems troublesome from a security, portability, and complexity
standpoint.) For these users, having a local copy of the prep tool
that has an option to just inline all local files would be terribly
useful. That option would be a proper subset of the steps given in
Section 5.
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A feature that might be useful in a local prep tool would be the
inverse of the "just inline" option would be "extract all". This
would allow a user who has a v3 RFC or Internet-Draft to dump all of
the <artwork> and <sourcecode> elements into local files instead of
having to find each one in the XML. This option might even do as
much validation as possible on the extracted <sourcecode> elements.
This feature might also remove some of the features added by the prep
tool (such as part numbers and slugifiedName's starting with "n-") in
order to make the resulting file easier to edit.
7. IANA Considerations
None.
8. Security Considerations
Steps in this document attempt to prevent the <artwork> and
<sourcecode> entities from exposing the contents of files outside the
directory in which the document being processed resides. For
example, values starting with "/", "./", or "../" should generate
errors.
The security considerations in [RFC3470] apply here. In specific,
processing XML external references can expose a prep tool
implementation to various threats by causing the implementation to
access external resources automatically. It is important to disallow
arbitrary access to such external references within XML data from
untrusted sources.
9. Acknowledgements
Many people contributed valuable ideas to this document. Special
thanks go to Robert Sparks for his in-depth review and contributions
early in the development of this document, and to Julian Reschke for
his help getting the document structured more clearly.
10. Informative References
[I-D.iab-rfc5741bis]
Halpern, J., Daigle, L., and O. Kolkman, "On RFC Streams,
Headers, and Boilerplates", draft-iab-rfc5741bis-02 (work
in progress), February 2016.
[I-D.iab-xml2rfc]
Hoffman, P., "The "xml2rfc" version 3 Vocabulary", draft-
iab-xml2rfc-04 (work in progress), June 2016.
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[RFC3470] Hollenbeck, S., Rose, M., and L. Masinter, "Guidelines for
the Use of Extensible Markup Language (XML) within IETF
Protocols", BCP 70, RFC 3470, DOI 10.17487/RFC3470,
January 2003, <http://www.rfc-editor.org/info/rfc3470>.
[RFC6949] Flanagan, H. and N. Brownlee, "RFC Series Format
Requirements and Future Development", RFC 6949,
DOI 10.17487/RFC6949, May 2013,
<http://www.rfc-editor.org/info/rfc6949>.
[RFC7669] Levine, J., "Assigning Digital Object Identifiers to
RFCs", RFC 7669, DOI 10.17487/RFC7669, October 2015,
<http://www.rfc-editor.org/info/rfc7669>.
Authors' Addresses
Paul Hoffman
ICANN
Email: paul.hoffman@icann.org
Joe Hildebrand
Cisco
Email: jhildebr@cisco.com
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