INTERNET-DRAFT P. Grau
<draft-dfncis-netnews-admin-sys-01.txt> V. Heinau
Expires November 27, 2000 H. Schlichting
DFN-CIS
May 2000
Netnews Administration System (NAS)
<draft-dfncis-netnews-admin-sys-01.txt>
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of section 10 of [RFC2026].
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.
Abstract
The Netnews Administration System (NAS) is a framework to simplify
the administration and usage of network news on the Internet. Data
for the administration of newsgroups and hierarchies are kept in a
distributed hierarchical database, and are available through a
client-server-protocol.
The database is accessible by news servers and news administrators as
well as by news readers. News servers can update their configuration
automatically, administrators are able to get the data manually. News
reader programs are able to get certain information from an NAS
server, automatically or at a user's discretion, to provide detailed
information about groups and hierarchies to the user.
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NAS is usable in coexistence with the current, established process of
control messages, an unwanted interference is impossible.
Furthermore, NAS is able to reflect the somewhat chaotic structure of
Usenet in a hierarchical database. NAS can be used without
modification of existing news relay, news server or news reader
software, however some tasks will be better accomplished with NAS
compliant software.
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Table of Contents
Status of this Memo ............................................... 1
Abstract .......................................................... 1
1. Introduction .................................................. 4
2. Overview ...................................................... 5
3. Protocol Level ................................................ 6
4. Description of Functions ...................................... 7
5. Definitions ................................................... 8
6. Specification of the NAS Protocol (TCP) ....................... 8
6.1. Responses ............................................... 8
6.1.1. Overview .......................................... 8
6.1.2. Response Code Values, Structure and Meaning ....... 9
6.2. Connection setup ........................................ 10
6.3. Commands ................................................ 10
6.3.1. Structure ......................................... 10
6.3.2. Overview .......................................... 11
6.3.3. Detailed Description .............................. 11
6.3.3.1. HELP ........................................ 11
6.3.3.2. INFO ........................................ 13
6.3.3.3. DATE ........................................ 14
6.3.3.4. VERS ........................................ 15
6.3.3.5. QUIT ........................................ 16
6.3.3.6. LIST ........................................ 16
6.3.3.7. LSTR ........................................ 18
6.3.3.8. HIER ........................................ 20
6.3.3.9. DATA ........................................ 21
6.3.3.10. GETL ....................................... 23
6.3.3.11. GETP ....................................... 24
6.3.3.12. GETA ....................................... 27
6.3.3.13. Unknown Commands and Syntax Errors ......... 29
6.3.4. Data Headers ...................................... 29
6.4. Status Indicators ....................................... 41
6.5. Newsgroup Types ......................................... 41
6.6. Hierarchy Types ......................................... 42
6.7. PGP Keys ................................................ 42
7. Specification of the NAS Protocol (UDP) ....................... 43
8. Security Considerations ....................................... 44
9. References .................................................... 44
10. Author's Address ............................................. 45
Appendix A - Response Codes (Overview) ............................ 45
Appendix B - Data Header for DATA and HIER Commands (Overview)
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1. Introduction
The increasing number of newsgroups, hierarchies and articles has
made the administration of news servers a complex and time consuming
task. The tools for the administration are unchanged for nearly ten
years now and no longer appropriate. Many hierarchies are
inconsistent, many new newsgroups are not created or only with a huge
delay, removed groups keep lurking in the configuration files for a
long period of time. There is no administration tool that utilizes
the power of the Internet, nor is there a possibility to check the
consistency of the news server at a given point of time.
Users have difficulties to get an overview of the newsgroups, the
charter of a particular one, which language is preferred, or whether
a group is moderated or not. Renaming, the status change from
moderated to unmoderated or vice versa, the splitting of a group into
several others are dynamic processes. These processes are common use,
but it takes a long time until every news server is aware of these
changes.
An increasing number of faked control messages appeared in the last
few years. Purposely or accidentally control messages were sent to
foreign news servers to create or remove a certain group, although
this task was not approved by the rules of the hierarchy in question.
Due to this fact, on many news servers the automatic creation is
disabled and several dead groups have not been deleted. It is very
difficult for users to determine the status of a group, and therefore
the propagation of articles is affected by this fact.
It is the design goal of NAS to provide a out of band system that
helps to maintain, propagate and deliver the required information.
There will not be any interference with current protocols and
standards. It is not intended to make use of control messages or some
special nntp commands. The advantage of NAS is that it provides more
information in a more structured format than control messages. Not
only news server administrators but also Usenet users can get more
detailed information about newsgroups and hierarchies.
Due to the fact that a client connects to a server, and the server
asks for authentication, this is is a more resonable procedure of
transmitting information than control messages. Futhermore it is
possible to check for changes on a regular basis at customized
intervals to keep local data uptodate.
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2. Overview
NAS is based on a database which contains information belonging to
certain groups and hierarchies. This database is structured in a
hierarchical manner, distributed to various servers and is able to
receive queries at any time. The service is comparable to directory
services like DNS, LDAP or NIS. The NAS protocol is inspired by
protocols like NNTP and SMTP. There already is a reserved port
number for NAS, 991. It is registered by the Internet Assigned Number
Authority (IANA) [IANA-PN].
The organizational structure of NAS is hierarchical, that means an
NAS root server collects data from the subservers which are
authoritative for certain hierarchies. The root server signs the data
and distributes it authoritatively. Replication of database entries
is possible. The hierarchical structure can consist of multiple
levels. Usage of the database is possible for news servers, news
readers and special client programs. The communication is based on
TCP and UDP.
Taking the real world in account, there migth be some policy problems
with a single root server. But it is possible to establish a
structure like the current Usenet system, where some hierarchies have
a good administration with a well defined system of rules and some
which are not well maintained. The goal is to get as much information
as possible under one hat, but there can be no "official" force to
achieve this.
During the startup phase it's quite likely that there will be a root
server, handling just hierarchies with strict rules and accepted
authorities (like BIG8, de.*, us.*, bln.*, fr.*, it.*, etc.).
However it is also imaginable to have some NAS servers providing data
on - for exapmle - alt.!binaries, some providing data on alt.*, and
even some providing alt.* following special policies or sets of
rules.
An administrator using NAS will have the choice to use just one root
server (and all its data) and/or to use another NAS server for
special hierarchies.
.............. .............. ...................
. NAS server . . NAS server . . NAS server .
. . . . . alt.*, .
. alt.* . . Big8 . . !alt.binaries.* .
.............. .............. ...................
. database . . database . . database .
.............. .............. ...................
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^ ^ ^ ^
`--+ +--' `------+ +----'
| | | |
.------------. .------------.
| NAS client | | NAS client |
+------------+ +------------+
| netnews | | netnews |
| server | | server |
.------------. .------------.
Configuration A Configuration B
NAS contains information about newsgroups as well as complete
hierarchies. Furthermore it contains the information about the
hierarchies' inheritable entries and default values for a single
newsgroup.
3. Protocol Level
It is expected that the real life use of NAS will change the
requirements for the Netnews Administration System. On one hand the
protocol has to be extensible and flexible in order to implement
improvements. On the other hand it must ensure compatibility between
different versions. A simultaneous migration of all sites using NAS
to a new protocol version is not likely to happen. To solve this
problem, NAS has got a protocol level defined. This protocol level
describes the current functionality. The protocol level, being a
number between 1 and 32767, is negotiated at connection setup.
Enhancements and modifications must use a different protocol level
than their predecessors. (Usually the protocol level is incremented
by 1 with every new version of the protocol specification.) Every
current or future implementation must be compatible with the protocol
level 1, in order to fall back to this level when communication on a
higher level fails.
An implementation of higher protocol levels should be able to emulate
the behavior of lower levels, even if this implies a loss of
features. The negotiation of the protocol level between client and
server is described in the specification of the command VERS. If
there is no agreement on the protocol level, only commands of the
protocol level 1 must be used. Documents enhancing or modifying the
NAS standard must specify from upon which level these changes take
place and how the behavior should be in other protocol levels.
This document describes protocol level 1.
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4. Description of Functions
In order to use an NAS server, a connection must be opened by the
client. The NAS server can be located in the same domain or somewhere
else on the Internet.
The NAS system is hierarchical. The idea is to have an NAS root
server like the DNS root servers. The root server distributes the
data collected from client NAS servers, which are authoritative
servers for their hierarchy. The maintenance of the authoritative
data is possible on any system. The root server collects the data and
makes them available to other servers, which also can distribute
these data to other servers. The administrator has the opportunity to
make use of either all data or only parts of the database. NAS
servers can ask multiple NAS servers for data. An attached time stamp
provides the possibility to distinguish between new and old data, and
to avoid loops in the propagation.
To describe the NAS in greater detail it is necessary to emphasize
the hierarchical design of the NAS system. The following picture
shows the propagation of data along the server hierarchy. There are
two kinds of data collection: In first place the authoritative data
for a newsgroup or a hierarchy are collected, and written into a
database. This database is made available to a local NAS server. The
data will then be collected by the upstream NAS server.
............ collects from >
. root NAS .-------------------------+
. server .----------------+ |
............ | |
. database . | |
............ | |
^ v | ..............
| | | . de.* .
| |distributes | . NAS server .
queries| | | ..............
| | | . database .
^ v | ..............
............ |
. database . `--------+
. with NAS . |
. client . ..............
............ . bln.* .
^ ^ ^ . NAS server .
| | | .---------. ..............
q | | `--| netnews | . database .
u | | | server | ..............
e | | .---------.
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r | |
i | | .---------.
e | `--| admin |
s | | program |
| .---------.
|
| .---------.
`--| news |
| reader |
.---------.
Requests to an NAS server originating at a client as well as
another server are accomplished in several steps, as there are:
Establishing a connection, authentication (optional),
negotiating a protocol level (optional), queries on
the database, and termination.
5. Definitions
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 [RFC2119].
6. Specification of the NAS Protocol (TCP)
6.1. Responses
6.1.1. Overview
An answer will start with a response code (a three digit number),
optionally followed by white space and a textual message. Then the
actual Text/Data will follow. Text is send as a series of successive
lines of textual matter, each terminated with CRLF. A single line
containing only a single period ('.') is sent to indicate the end of
the text (i.e. the server will send a CRLF at the end of the last
line of text, a period, and another CRLF).
Answer = Status [ WSP Text] CRLF
Data CRLF;
"." CRLF
If the original text containes a period as the first character of the text
line, that first period is doubled. Therefore, the client must examine the
first character of each line received, and for those beginning with a period,
determine either that this is the end of the text or whether to collapse the
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doubled period to a single one.
Example:
<-- INFO
--> 101 Information follows
Server: nas.fu-berlin.de (160.45.11.141)
Uptime: 2 weeks, 3 days, 5 hours, 9 minutes
Software: NAS 1.0
Client: waran.cis.fu-berlin.de (160.45.11.136)
Connection: 9 minutes
Highest protocol level supported: 1
Requested protocol level: 1
Protocol level used: 1
.
6.1.2. Response Code Values, Structure and Meaning
The first digit of the response code indicates the message type, i.e.
informational, success, warning, error, data:
1xx Information
2xx Request successful
3xx Request successful, data follow
4xx Request accepted, but no operation possible
5xx Request is wrong (syntax error), not implemented, or leads to an
internal error
6xx Request successful, data follow until end mark
The second digit specifies the message category:
x0x connection related stuff
x1x queries, answers, data
x2x server-server communication
x3x authentication, authorization
x8x non-standard extensions
x9x debugging output
The actual response code for a specific command is listed in the
description of the commands. Answers of the type 1xx, 2xx, 4xx, and
5xx can have a text after the numerical code. 3xx answers contain one
or more parameters with data, the exact format is explained in the
description of the commands.
An answer to an incorrect request may be longer than one line.
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6.2. Connection setup
NAS typically uses port 991, which is reserved by IANA [IANA-PN]. If
a connection is set up by the client, the server answers immediately
(without a request) with the greeting message, which will start with
code 200:
--> 200 Welcome!
nas.fu-berlin.de ready
.
If a connection is refused because the client has no permission
to access the server, the answer code is 434. When the server
is currently out of service, the answer code is 404.
Examples:
434 You have no permission to retrieve data. Good bye.
404 Maintenance time
After sending a 404 or 434 message the connection will be closed.
6.3. Commands
6.3.1. Structure
A command consists of a command word, sometimes followed by a
parameter. Parameters are separated from the command word by white
space.
Commands used in the NAS protocol are not case sensitive. A command
word or parameter may be upper case, lower case, or any mixture of
upper and lower case.
The length of a command line is not limited.
The protocol level described in this document uses command words with
a length of exactly four characters each.
In examples, octets sent to the NAS server are preceded by "<-- " and
those sent by the NAS server by "--> ". The indicator is omitted if
the direction of the dialog does not change.
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6.3.2. Overview
The commands described below are defined using the Augmented Backus-
Naur Form (ABNF) defined in [RFC2234]. The definitions for `ALPHA',
`CRLF', `DIGIT', `WSP' and `VCHAR' are taken from appendix A of
[RFC2234] and not repeated here.
The following ABNF definitions comprise the set of NAS commands which
can be sent from the client to an NAS server.
6.3.3. Detailed Description
Some overall definitions:
text = %d1-9 / ; all octets except
%d11-12 / ; US-ASCII NUL, CR and LF
%d14-255
answertext = WSP *(ALPHA / DIGIT / "+"/ "-"/ "/"/ "_"/ "="/ "?"/ "!"/ SP)
utc-time = 14*DIGIT ; The date and time of the server in UTC
; YYYYMMDDhhmmss
Newsgroup names and hierarchy names are defined according to the
following ABNF definitions. Since a hierarchy name can be the same as
a newsgroup name (e.g., hierarchy bln.announce.fub.* and newsgroup
name bln.announce.fub) there is no difference between the two.
hierarchy-name = newsgroup-name ; these two are identical
newsgroup-name = plain-component *( "." component )
component = plain-component / encoded-word
encoded-word = lowercase / DIGIT
=/ "+"/ "-"/ "/"/ "_"/ "="/ "?"
plain-component = first-component-start component-rest
first-component-start = lowercase
component-start = lowercase / digit
lowercase = %x61-7a ; letter a-z lowercase
component-rest = component-start / "+"/ "-"/ "_"
NOTE: This definition of a newsgroup name is according to
son-of-1036-draft [SON1036]. When the current draft "News Article
Format" [USRFOR] is established as an RFC, it's definitions should be
integrated into a higher protocol level of NAS.
6.3.3.1. HELP
Description
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This command prints a short help text on a given command. If called
without parameters it will display a complete list of commands.
help-cmd = "HELP" [ WSP Commandname ] CRLF
Commandname = "DATA" / "DATE" / "GETL" / "GETP" / "GETA"
=/ "HELP" / "HIER" / "INFO" / "LIST" / "LSTR"
=/ "QUIT" / "VERS"
Possible answers
100: Command overview, command description
410: Indicates that the server is not giving any information
help-answer = "410" [ answertext ] CRLF
text CRLF
"." CRLF
=/ "100" [ answertext ] CRLF
text CRLF
"." CRLF
Examples
<-- HELP
--> 100 NAS server nas.fu-berlin.de, Version 1.0
Supported commands:
DATA - data for a newsgroup
DATE - show time of server in UTC
GETL - get list of hierarchy packages
GETP - get package
GETA - get data from an authoritative server
HELP - show this help
HIER - data for a hierarchy
INFO - show info on current connection
LIST - list newsgroups or hierarchies
LSTR - recursive list newsgroups or hierarchies
QUIT - close the connection
VERS - show or set current protocol level
Contact address nas@cis.fu-berlin.de
.
<-- HELP LIST
--> 100 LIST
LIST - list newsgroups or hierarchies
Syntax: LIST hierarchy ...
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Get a list of newsgroups and sub-hierarchies
directly under the parameter hierarchy
.
<-- HELP NOOP
--> 410
unknown command "NOOP"
.
6.3.3.2. INFO
Description
Prints information about the current connection, the server, and the
client.
info-cmd = "INFO" CRLF
Possible answers
101: Normal answer, prints some information about client
and server
400: Indicates that the server is not giving any information
info-answer = "400" [ answertext ] CRLF
text CRLF
"." CRLF
=/ "101" [ answertext ] CRLF
text CRLF
"." CRLF
Examples
<-- INFO
--> 101 Information follows
Server: nas.fu-berlin.de (160.45.11.141)
Uptime: 2 weeks, 3 days, 5 hours, 9 minutes
Software: NAS 1.0
Client: waran.cis.fu-berlin.de (160.45.11.136)
Connection: 9 minutes
Highest protocol level supported: 1
Requested protocol level: 1
Protocol level used: 1
End
.
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<-- INFO
--> 400
No information available.
.
6.3.3.3. DATE
Description
Prints the actual time of the server in UTC (Universal Coordinated
Time) in the format YYYYMMDDhhmmss, followed by an optional comment.
The DATE command is only for informational use and to control the
server time. For regular transmission of time over the network the
NTP protocol [RFC1305] should be used.
date-cmd = "DATE" CRLF
Possible answers
300: Print the UTC time in specified format, see below
511: Error, print an error message
date-answer = "511" [ answertext ] CRLF
text CRLF
"." CRLF
=/ "300" [ answertext ] CRLF
utc-time [ answertext ] CRLF
"." CRLF
Examples
<-- DATE
--> 300
19990427135230 UTC
.
<-- DATE
--> 511
Time is unknown
.
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6.3.3.4. VERS
Description
The VERS command is used to determine the protocol level used between
client and server. The parameter is a protocol level which the client
supports and wants to use. The server will respond with the highest
level that will be accepted. That version number must not be higher
than requested by the client. Client and server must only use
commands from the level that the server has confirmed. It is
possible, but seldom necessary, to change the protocol level during a
session by client request (VERS [protocol level]). When no option is
given, the current protocol level will be printed. When no protocol
level is negotiated, the protocol level 1 will be used. Commands of a
higher level are not allowed without a successful negotiation. The
protocol level can be followed by an optional comment.
vers-cmd = "VERS" [ WSP level ] CRLF
level = 1*5DIGIT ; the valid range is 1 - 32767
Possible answers
202: Returns current protocol level
302: Answer to an successful request
402: Requested level too high, falling back to lower level
510: Syntax error
vers-answer = "202" [ answertext ] CRLF
level [ answertext ] CRLF
"." CRLF
=/ "302" [ answertext ] CRLF
level [ answertext ] WSP level CRLF
"." CRLF
=/ "402" [ answertext ] CRLF
level [ answertext ] WSP level CRLF
"." CRLF
=/ "510" [ answertext ] CRLF
level [ answertext ] CRLF
"." CRLF
Examples
<-- VERS
--> 202
2 Current protocol level is 2
.
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<-- VERS 2
--> 302
2 My max protocol level is 10
.
<-- VERS 11
--> 402
10 Falling back to level 10
.
<-- VERS BAL
--> 510
1 Syntax error
.
6.3.3.5. QUIT
Description
Terminates the connection.
quit-cmd = "QUIT" CRLF
Possible answers
201: Termination of the connection
quit-answer = "201" [ answertext ] CRLF
Examples
<-- QUIT
--> 201 Closing connection. Bye.
6.3.3.6. LIST
Description
To obtain a list of newsgroups and sub-hierarchies in the requested
hierarchies the command LIST is used. The status of the hierarchies
is also given. The highest level consists of all top-level
hierarchies and is labeled "*". It can be obtained this way, too.
After the response code 610 follow white space and the end mark. The
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last line of the data stream must begin with the end mark. The end
mark will be checked case insensitive. Comments after the separating
white space are allowed.
The data consist of a newsgroup- or hierarchy-name/status indicator
pair per line. Name and status indicator must be separated by at
least one white space. The status indicator is one letter (see
section 6.3.5). The interpretation is not case sensitive.
list-cmd = "LIST" ( "*" | 1*(WSP hierarchy-name)) CRLF
Possible answers
401: Permission denied
530: The parameter "hierarchy" is missing
610: Regular answer with all requested data
list-answer = "610" [ answertext ] CRLF
*( listdata CRLF )
"." CRLF
=/ "401" [ WSP text ] CRLF
text CRLF
"." CRLF
=/ "530" [ WSP text ] CRLF
text CRLF
"." CRLF
listdata = newsgroup-name WSP list-status CRLF
The list-status is the status of a newsgroup or hierarchy according
to section 6.4.
list-status = "Hierarchy-Complete"
=/ "Hierarchy-Incomplete"
=/ "Hierarchy-Obsolete"
=/ "Hierarchy-Unkown"
=/ "Group-Post-Yes"
=/ "Group-Post-No"
=/ "Group-Moderated"
=/ "Group-Removed"
=/ "Group-Unkown"
; list-status is case-insensitive
Examples
<-- LIST *
--> 610 data follow
alt Hierarchy-Incomplete
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bln Hierarchy-Complete
comp Hierarchy-Complete
de Hierarchy-Complete
rec Hierarchy-Complete
sub Hierarchy-Obsolete
.
<-- LIST de
--> 610 data follow
de.admin Hierarchy-Complete
de.alt Hierarchy-Incomplete
de.comm Hierarchy-Complete
de.comp Hierarchy-Complete
de.etc Hierarchy-Complete
de.markt Hierarchy-Complete
de.newusers Hierarchy-Complete
de.org Hierarchy-Complete
de.rec Hierarchy-Complete
de.sci Hierarchy-Complete
de.soc Hierarchy-Complete
de.talk Hierarchy-Complete
de.answers Group-Moderated
de.test Group-Post-Yes
.
<-- LIST foo
--> 610 data follow
foo Hierarchy-Unkown
.
<-- LIST
--> 530
missing parameter hierarchy
.
<-- LIST de
--> 401 Some thing is wrong
Permission denied
.
6.3.3.7. LSTR
Description
To obtain a recursive list of newsgroups and sub-hierarchies in the
named hierarchy the command LSTR is used. The status of the
hierarchies is also given. The highest level consists of all top-
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level hierarchies and is labeled "*". It can be obtained this way,
too.
The use of wildmat patters is also possible, so a "LSTR de.a*" would
return a list of all newsgroup starting with de.a*.
Note: This is according to wildmat(3) from libinn, it SHOULD be possible
to issue requests in the style of the newsfeeds(5) pattern for newsgroup
syntax.
lstr-cmd = "LSTR" ( "*" | 1*(WSP hierarchy-name)) CRLF
Possible answers
401: Permission denied
530: The parameter "hierarchy" is missing
610: Regular answer with all requested data
lstr-answer = "610" [ answertext ] CRLF
*( listdata CRLF )
"." CRLF
=/ "401" [ answertext ] CRLF
text CRLF
"." CRLF
=/ "530" [ answertext ] CRLF
text CRLF
"." CRLF
listdata = newsgroup-name WSP list-status CRLF
Examples
<-- LSTR de.admin
--> 610 recursive mode
de.admin Hierarchy-Complete
de.admin.archiv Group-Post-Yes
de.admin.infos Group-Moderated
de.admin.lists Group-Moderated
de.admin.misc Group-Post-Yes
de.admin.net-abuse Hierarchy-Complete
de.admin.net-abuse.announce Moderated
de.admin.net-abuse.mail Group-Post-Yes
de.admin.net-abuse.misc Group-Post-Yes
de.admin.net-abuse.news Group-Post-Yes
de.admin.news Hierarchy-Complete
de.admin.news.announce Group-Moderated
de.admin.news.groups Group-Post-Yes
de.admin.news.misc Group-Post-Yes
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de.admin.news.nocem Group-Post-Yes
de.admin.news.regeln Group-Post-Yes
de.admin.submaps Group-Moderated
.
6.3.3.8. HIER
Description
The command HIER lists all available information about the hierarchy.
With data header "Name" a new data block for each hierarchy is
started. Code "Name" gives the name of the hierarchy. The data
headers are described in section 6.3.4. The default is to transmit
all aviable information. It can be limited to a list of desired
headers ("Name" and "Status" are allways given). A set of comma
separated headers as a option to the HIER command will return the
requested header fields.
hier-cmd = "HIER" [ WSP range ] 1*( WSP hierarchy-name) CRLF
range = *( header ",") header ; Describes the data fields
; that are requested
header = *( ALPHA / "-") ; According to section 6.3.4
Examples for range:
Followup,Description : for all entries list Name, Status, Followup
and Description
Possible answers
401: Permission denied
530: Missing parameter
611: Regular answer with all requested data
hier-answer = "611" [ answertext ] CRLF
*( hierdata CRLF )
"." CRLF
=/ "530" [ answertext ] CRLF
*( text CRLF )
"." CRLF
=/ "401" [ answertext ] CRLF
*( text CRLF )
"." CRLF
hierdata = "Name:" WSP test CRLF
"Status:" WSP text CRLF
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*( header ":" WSP text CRLF )
( "Ctl-PGP-Key:" CRLF PGP-answer )
( "Mod-PGP-Key:" CRLF PGP-answer )
PGP-answer: The exact format is described in section 6.7
Examples
<-- HIER de
--> 611 Data coming
Name: de
Status: Hierarchy-Complete
Description: Internationale deutschsprachige Newsgruppen
Netiquette: http://www.dana.de/de/netiquette.html
Faq: http://www.dana.de/de/neue-de-gruppe.html
Ctl-Send-Adr: moderator@dana.de
Ctl-Newsgroup: de.admin.news.announce
Mod-Wildcard: %s@moderators.dana.de
Language: DE
Charset: ISO-8859-1
Encoding: text/plain
Newsgroup-Type: Discussion
Hier-Type: Int
Name-Length: 14
Date-Create: 199201060000
.
<-- HIER bln
--> 401
Permission denied
.
<-- HIER
--> 530 There is an error
missing parameter hierarchy
.
6.3.3.9. DATA
Description
The DATA command corresponds to the HIER command, but it is used for
information about a newsgroup. A summary of codes can be found in
section 6.3.4.
data-cmd = "DATA" [ WSP range ] 1*( WSP newsgroup-name ) CRLF
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Possible answers
401: Permission denied
530: Missing parameter
612: Regular answer with all requested data
data-answer = "612" [ answertext ] CRLF
*( datadata CRLF )
"." CRLF
=/ "530" [ answertext ] CRLF )
text CRLF
"." CRLF
=/ "401" [ answertext ] CRLF
text CRLF
"." CRLF
datadata = "Name:" WSP test CRLF
"Status:" WSP text CRLF
*( header ":" WSP text CRLF )
( "Ctl-PGP-Key:" CRLF PGP-answer )
( "Mod-PGP-Key:" CRLF PGP-answer )
Examples
<-- DATA de.comp.os.unix.linux.moderated
--> 612 data follow
Name de.comp.os.unix.linux.moderated
Status: Group-Moderated
Description: Linux und -Distributionen.
<dcoulm-moderators@linux-config.de>
Charter: http://www.dana.de/mod/chartas/de.comp.html#de.comp.
os.unix.linux.moderated
Netiquette: http://www.dana.de/de/netiquette.html
Netiquette: ftp://ftp.fu-berlin.de/doc/usenet/german
/netiquette.gz
Mod-Sub-Adr: dcoulm-moderators@linux-config.de
Mod-Group-Info: http://wpxx02.toxi.uni-wuerzburg.de/~dcoulmod/
Newsgroup-Type: Discussion
.
<-- DATA de.foo
--> 612 data follow
Name: de.foo
Status: Incomplete
.
<-- DATA de
--> 401
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Permission denied
.
<-- DATA
--> 530
missing parameter newsgroup
.
6.3.3.10. GETL
Description
The GETL command is intended for server-server communication; it will
request the list of packages that a server is offering. A package is
the complete information available for a hierarchy or newsgroup, i.e.
all entries that have a value including PGP keys. The format of the
data is the same as for the commands "HIER" and "LIST".
The server will send a list of available and distributable hierarchy
packages.
getl-cmd = "GETL" CRLF
Possible answers
401: Permission denied
614: Lists all packages a server is authoritative for
getl-answer = "614" [ answertext ] CRLF
*( getldata )
"." CRLF
=/ "401" [ answertext ] CRLF
text CRLF
"." CRLF
getldata = *( newsgroup-name CRLF )
Examples
<-- GETL
--> 614 data follow
de
.
<-- GETL
--> 614 data follow
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de
hk
comp
rec
[...]
bln
.
6.3.3.11. GETP
Description
GETP requests the packages specified by the parameter "Package". If
"*" is given as package name, all data the server is offering will be
transmitted. The "serial" is the date and time the package was last
obtained by the client, so the server can check if the data on the
client side is still valid or if it is too old. If the data on the
client side is still valid a 213 answer is sent, so the client knows
that his data is ok. If the serial is "0", the server is forced to
transmit the data.
The data for a successful request are sent in ASCII armor according
to [RFC2440], so a client has the possibility to check the signature
or to ignore it. The actual data will be surrounded by an indicator
which indicates the signing method, the beginning mark, and the end
mark. These specifications will be included in the signed text block.
getp-cmd = "GETP" WSP password WSP serial
WSP ( "0" / *[ WSP hierarchy-name ] ) CRLF
password = *VCHAR / "0"
serial = utc-time ; date and time of the last retrieval
=/ "0" ; force the transmission of data
Possible answers
213: Current data at the client side
411: No package with that name
430: Permission denied
530: Missing parameter
613: Package data
getp-answer = "613" [ answertext ] CRLF
pgp-start-mark ; this is according to [RFC2440]
"GETP" WSP "SIGN" WSP method CRLF
"GETP" WSP "BEGIN" CRLF
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*( getpdata CRLF)
"GETP" WSP "END" CRLF
pgp-end-mark ; this is according to [RFC2440]
"." CRLF
=/ "213" [ answertext ] CRLF
text CRLF
"." CRLF
=/ "430" [ answertext ] CRLF
text CRLF
"." CRLF
=/ "411" [ answertext ] CRLF
text CRLF
"." CRLF
=/ "530" [ answertext ] CRLF
text CRLF
"." CRLF
Currently the following methods are supported:
method = "PGP2" / "PGP5" / "GPG"
; PGP version 2, PGP version 5 and GnuPG
pgp-start-mark and the pgp-end-mark are build according to [RFC2440]
Section 6.2. "Forming ASCII Armor".
getpdata = "Name:" WSP test CRLF
"Status:" WSP text CRLF
*( header ":" WSP text CRLF )
( "Ctl-PGP-Key:" CRLF PGP-answer )
( "Mod-PGP-Key:" CRLF PGP-answer )
Examples
<-- GETP 0 0 humanities
--> 613 data follow
-----BEGIN PGP SIGNED MESSAGE-----
GETP SIGN PGP2
GETP BEGIN
Name: humanities
Status: Hierarchy-Complete
Description: branches of learning that investigate human
constructs and concerns as opposed to natural processes
Netiquette: ftp://rtfm.mit.edu/pub/usenet/news.announce.newusers/
A_Primer_on_How_to_Work_With_the_Usenet_Community
Rules: http://www.uvv.org/formus/big8creation.htm
Ctl-Send-Adr: group-admin@isc.org
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Ctl-Newsgroup: news.announce.newgroup
Lanugage: EN
Chatset: US-ASCII
Encoding: text/plain
Newsgroup-Type: Discussion
Hier-Type: Global
Comp-Length: 14
Date-Create: 19950417143009
Name: humanities.answers
Status: Moderated
Description: Repository for periodic USENET articles. (Moderated)
Mod-Sub-Adr: news-answers@mit.edu
Mod-Adm-Adr: news-answers-request@mit.edu
Newsgroup-Type: Announce
Date-Create: 19950725182040
Name: humanities.classics
[...]
GETP END
-----BEGIN PGP SIGNATURE-----
Version: 2.6.3in
Charset: noconv
iQCVAwUBOBhmWTiii3auEmclAQEM9wP9FVem1VXYrywFa2FLEh1apsay9yJC9jKT
V80U1M1LAKkR+xkXZdczd/PIGEAQapauKjINpxFOgynMWd8A2Ta0y4s4ZXHgEiZP
A/tKaMGi/7roZwUp8ERQRBsvc54kckgnX57HiVUgsbVd41FHPTvsVLv/QIHmqaGd
fR5aQJfwKhE=
=Sg4p
-----END PGP SIGNATURE-----
.
<-- GETP 0 199909091010 de
--> 213
You are uptodate
.
<-- GETP foo
--> 530
Missing parameters
.
<-- GETP test 0 de
--> 430
You have no permission to retrieve the data
Cause: Wrong IP number
.
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6.3.3.12. GETA
Description
The GETA command is used for server-server communication; it will
request packages that the server is authoritative for. A package is
the authoritative data either for a newsgroup or a hierarchy. Each
package has a serial number attached to control the age of the
package. Serial is a number that is the date in UTC format of the
last known modification of the package. A serial of "0" indicates
that the package MUST be retrieved. If the retrieving client has a
recent package (i.e. no modification on the authoritative server) the
server sends only a 215 response. The format of the data is the same
as for the commands "HIER" and "LIST".
geta-cmd = "GETA" WSP password WSP serial WSP hierarchy-name CRLF
password = *VCHAR / "0"
Possible answers
215: The client already has the current data
430: Permission denied
411: No package with that name
530: Missing parameter
615: Regular answer with all requested data
geta-answer = "615" [ answertext ] CRLF
pgp-start-mark ; this is according to [RFC2440]
"GETA" WSP "SIGN" WSP method CRLF
"GETA" WSP "BEGIN" CRLF
*( getadata CRLF)
"GETA" WSP "END" CRLF
pgp-end-mark ; this is according to [RFC2440]
"." CRLF
=/ "215" [ answertext ] CRLF
text CRLF
"." CRLF
=/ "430" [ answertext ] CRLF
text CRLF
"." CRLF
=/ "411" [ answertext ] CRLF
text CRLF
"." CRLF
=/ "530" [ answertext ] CRLF
text CRLF
"." CRLF
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geta-data = 2*( *( datacode "-" text CRLF ) datacode WSP text)
Examples
<-- GETA 0 0 humanities
--> 613 data follow
-----BEGIN PGP SIGNED MESSAGE-----
GETA SIGN PGP2
GETA BEGIN
Name: humanities
Status: Hierarchy
Description: the branches of learning that investigate human
constructs and concerns as opposed to natural processes
Netiquette: ftp://rtfm.mit.edu/pub/usenet/news.announce.newusers/
A_Primer_on_How_to_Work_With_the_Usenet_Community
Rules: http://www.uvv.org/formus/big8creation.htm
Ctl-Send-Adr: group-admin@isc.org
Ctl-Newsgroup: news.announce.newgroup
Language: EN
Chartset: US-ASCII
Encoding: text/plain
Newsgroup-Type: Dissusion
Hier-Type: Int
Comp-Length: 14
Date-Create: 19950417143009
Name: humanities.answers
Status: Moderated
Description: Repository for periodic USENET articles. (Moderated)
Mod-Sub-Adr: news-answers@mit.edu
Mod-Adm-Adr: news-answers-request@mit.edu
Newsgroup-Type: Announce
Date-Create: 19950725182040
Name: humanities.classics
[...]
GETA END
-----BEGIN PGP SIGNATURE-----
Version: 2.6.3in
Charset: noconv
iQCVAwUBOBhmWTiii3auEmclAQEM9wP9FVem1VXYrywFa2FLEh1apsay9yJC9jKT
V80U1M1LAKkR+xkXZdczd/PIGEAQapauKjINpxFOgynMWd8A2Ta0y4s4ZXHgEiZP
A/tKaMGi/7roZwUp8ERQRBsvc54kckgnX57HiVUgsbVd41FHPTvsVLv/QIHmqaGd
fR5aQJfwKhE=
=Sg4p
-----END PGP SIGNATURE-----
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.
6.3.3.13. Unknown Commands and Syntax Errors
If a command is recognized as unknown, it MUST be ignored. If an
error occurs after the command string (e.g. a missing parameter) a
530 return code is given.
6.3.4. Data Headers
The following descriptions are keywords and key terms which support
retrieval and storing of information. Every header has a unique
English name.
The content of a header is inheritable within a hierarchy, as long as
the header is marked as inheritable. The content is the default value
for all downstream newsgroups and sub-hierarchies. For example in the
hierarchy "de" the language header has a value of "DE" (German),
therefore this value is true for all newsgroups in this hierarchy,
except those who explicitly define a language code of their own.
Hierarchies and newsgroups must at least have values for the header
"Name" and "Status". Unknown hierarchies get the status "Incomplete"
and unknown groups get the status "Unkown".
The header names used in the NAS protocol are not case sensitive. A
header may be upper case, lower case, or any mixture of upper and
lower case. But the prefered syntax is the first letter upper case up
to the end or a dash lower case, after a dash the first letter is
again upper case then lower case and so on.
Name
Name: Name
Used for: hierarchy
Mandatory: yes
Inheritable: no
Repeatable: no
Description: Name of a hierarchy
Comment: Start of a new data block
Example: Name: comp
Used for: newsgroup
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Mandatory: yes
Repeatable: no
Description: Name of a newsgroup
Comment: Start of a new data block
Example: Name: de.admin.news.announce
Status
Name: Status
Used for: hierarchy
Mandatory: yes
Inheritable: no
Repeatable: no
Description: Status of a hierarchy
Comment: For a detailed description see section 6.4.
Example: Status: Hierarchy-Complete
Used for: newsgroup
Mandatory: yes
Repeatable: no
Description: Status of a newsgroup
Comment: For a detailed description see section 6.4.
Example: Status: Group-Moderated
Group for followup
Name: Followup
Used for: newsgroup
Mandatory: no
Repeatable: no
Description: Name of the newsgroup, that will take the followup
postings of a moderated group.
Comment: The value can be used as default value for the
"Followup-To:" header on postings to a moderated group.
This value is only useful on groups which are moderated
(Status M) and have a dedicated discussion group.
Example: Followup: bln.announce.fub.zedat.d
(for the moderated group bln.announce.fub.zedat)
Short description
Name: Description
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Used for: hierarchy
Mandatory: no
Inheritable: no
Repeatable: no
Description: Short description of a hierarchy
Example: Description: Angelegenheiten, die den Grossraum Berlin
betreffen
(for the hierarchy bln)
Used for: newsgroup
Mandatory: no
Repeatable: no
Description: Short description of a newsgroup
Comment: This information is often presented to the news reader
upon selection of the newsgroup, and it should describe
the topics in brief, but meaningful.
Example: Description: Technisches zur Newssoftware
(for de.admin.news.software)
Charter-URL
Name: Charter
Used for: hierarchy
Mandatory: no
Inheritable: no
Repeatable: yes
Description: URL that points to the charter of a hierarchy
Example: Charter: ftp://ftp.fu-berlin.de/doc/news/bln/bln
(for the hierarchy bln)
Used for: newsgroup
Mandatory: no
Repeatable: yes
Description: URL that points to the charter of a newsgroup
Comment: This information should be presented to the
news reader upon selection of the newsgroup.
Example: Charter: http://www.dana.de/mod/charta/admin.html
Netiquette-URL
Name: Netiquette
Used for: hierarchy
Mandatory: no
Inheritable: yes
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Repeatable: yes
Description: URL that points to the netiquette of a hierarchy.
Comment: Since the netiquettes are often valid for
a complete hierarchy this is inheritable.
Example: Netiquette: http://www.dana.de/mod/netiquette.html
Used for: newsgroup
Mandatory: no
Repeatable: yes
Description: URL for Netiquette
Comment: If a group has some special rules, this is the
pointer to these rules.
Example: Netiquette: http://research.de.uu.net:8080/
de.sci.announce/faq
(for de.sci.announce)
Frequently Asked Questions (FAQ)
Name: FAQ
Used for: Newsgroup
Mandatory: no
Repeatable: yes
Description: URL for the FAQ of a newsgroup
Example: FAQ: http://www2.informatik.uni-wuerzburg.de/dclc-faq/
(for de.comp.lang.c)
Administration rules
Name: Rules
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: yes
Description: URL pointing to a document that describes the rules for
creating, deleting or renaming newsgroups in this
hierarchy.
Comment: Normally inherited from the (toplevel)
hierarchy
Example: Rules: http://www.dana.de/mod/einrichtung.html
(for the hierarchy de)
Control Email
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Name: Ctl-Send-Adr
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: yes
Description: Email address of the sender of control messages
Comment: Multiple addresses are valid
Example: Ctl-Send-Adr: group-admin@isc.org
(for the hierarchy sci)
Control newsgroup
Name: Ctl-Newsgroup
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: yes
Description: Name of the newsgroup that will get the postings for
checkgroups, rmgroup and newsgroup control messages.
Example: Ctl-Newsgroup: de.admin.news.groups
Moderators
Name: Mod-Wildcard
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: no
Description: Moderator wildcard for this hierarchy.
Comment: This information can be used by the configuration of the
news system, for example the moderators file in INN.
Example: Mod-Wildcard: %s@moderators.dana.de
(for the hierarchy de)
Submission address
Name: Mod-Sub-Adr
Used for: newsgroup
Mandatory: no
Repeatable: yes
Description: Email address for submissions to the newsgroup.
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Comment: If there is no "Mod-Sub-Adr" for a moderated newsgroup,
"Mod-Wildcard" of the hierarchy is used. This is only
useful for moderated groups (Status Moderated).
Example: Mod-Sub-Adr: news-answers@mit.edu
(for the newsgroup news.answers)
Moderator's address (email)
Name: Mod-Adm-Adr
Used for: newsgroup
Mandatory: no
Repeatable: yes
Description: Email address of the moderator for the newsgroup.
Comment: If there is no code "Mod-Adm-Adr" for a moderated
newsgroup, "Mod-Wildacard" of the hierarchy is used.
This is only useful for moderated groups
(Status Moderated).
Example: Mod-Adm-Adr: news-answers-request@mit.edu
(for the newsgroup news.answers)
Info-URL
Name: Mod-Group-Info
Used for: newsgroup
Mandatory: no
Repeatable: yes
Description: URL that points to a document, where the moderator
presents information about the newsgroup and the
submission of articles.
Example: Mod-Group-Info: http://www.cs.helsinki.fi/u/mjrauhal/
linux/cola-submit.html
(for comp.os.linux.announce)
Language
Name: Language
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: yes
Description: The language that will normally be used in postings
Comment: The notation is according to [RFC1766], the
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"Content-Language" field. The languages that are not
the preferred language are enclosed in parenthesis.
Example: Language: DE
(for the hierarchy de)
Used for: newsgroup
Mandatory: no
Repeatable: yes
Description: The language that will normally be used in postings.
Comment: The notation is according to [RFC1766], the
"Content-Language" field. The languages that are not
the preferred language are enclosed in parenthesis.
Example: Language: TR
DE
(EN)
(for the newsgroup bln.kultur.tuerkisch)
Charset
Name: Charset
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: yes
Description: Charset that will normally be used in postings in this
hierarchy.
Comment: The complete set of charset names is defined by
[RFC2277] and the IANA Character Set registry [IANA-CS].
The charsets that are not the preferred charsets are
enclosed in parenthesis.
Example: Charset: ISO-8859-1
(for the hierarchy de)
Used for: newsgroup
Mandatory: no
Repeatable: yes
Description: Charset that will normally be used in
postings in this group.
Comment: The complete set of charset names is defined by
[RFC2277] and the IANA Character Set registry
[IANA-CS]. The charsets that are not the preferred
charsets are enclosed in parenthesis.
Example: Charset: ISO-8859-9
ISO-8859-1
(for the newsgroup bln.kultur.tuerkisch)
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Encoding
Name: Encoding
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: yes
Description: Encoding for this hierarchy according to MIME [RFC2045]
Comment: This is the media type used in this hierarchy, a list of
registered media types can be found at [IANA-MT]. The
encodings that are not the preferred encoding are
enclosed in parenthesis.
Example: Encoding text/plain
Used for: newsgroup
Mandatory: no
Repeatable: yes
Description: Encoding for this newsgroup according to MIME [RFC2045]
Comment This is the media type used in this newsgroup, a list of
registered media types can be found at [IANA-MT]. The
encodings that are not the preferred encoding are
enclosed in parenthesis.
Example: Encoding: text/plain
Type of newsgroup
Name: Newsgroup-Type
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: yes
Description: Default newsgroup type in this hierarchy
Comment: This code has no concrete meaning for a hierarchy, but
is used for the inheritance to newsgroups in the
hierarchy.
Specification of the types can be found in section 6.5
Example: Newsgroup-Type: Discussion
(for the hierarchy de)
Used for: newsgroup
Mandatory: no
Repeatable: yes
Description: Type of newsgroup
Comment: Specification of the types can be found in section 6.6
Example: Newsgroup-Type: Announce
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(for de.admin.news.announce)
Type of hierarchy
Name: Hier-Type
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: yes
Description: Type of hierarchy
Comment: Specification of the types can be found in section 6.6
Example: Hier-Type: Regional
(for hierarchy bln)
Regional or organizational area
Name: Area
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: yes
Description: Description of the geographical region or organization
of this hierarchy
Comment: This code is useful when the hierarchy type
(Hier-type) is "Regional" or "Organisation".
Example: Area: Grossraum Berlin
(for the hierarchy bln)
Name length of group names
Name: Name-Length
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: no
Description: Maximum length of a newsgroup name
Example: Name-Length: 72
(for the hierarchy bln)
Component length of group names
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Name: Comp-Length
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: no
Description: Maximum length of a single component in the newsgroup
name
Example: Comp-Length: 14
(for the hierarchy de)
Article length
Name: Article-Length
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: no
Description: Maximum length of an article in bytes.
Comment: This code has no concrete meaning for a hierarchy, but
is used for the inheritance to newsgroups in the
hierarchy.
Example: Article-Length: 50000
Used for: newsgroup
Mandatory: no
Repeatable: no
Description: Maximum length of an article in bytes
Example: Article-Length: 50000
Date of creation
Name: Date-Create
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: no
Description: Creation date of a hierarchy (can even be in future).
Comment: The format is the same as in the DATE command.
Example: Date-Create: 19970330101514
Used for: newsgroup
Mandatory: no
Repeatable: no
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Description: Creation date of a newsgroup (can even be in future).
Comment: The format is the same as in the DATE command.
Example: Date-Create: 19970330101514
Date of removal
Name: Date-Delete
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: no
Description: Date of removal of a hierarchy (can even be in future).
Comment: The format is the same as in the DATE command.
Example: Date-Delete: 19970330101514
Used for: newsgroup
Mandatory: no
Repeatable: no
Description: Date of removal of a newsgroup (can even be in future).
Comment: The format is the same as in the DATE command.
Example: Date-Delete: 19970330101514
Successor
Name: Replacement
Used for: hierarchy
Mandatory: no
Inheritable: no
Repeatable: yes
Description: Name of the hierarchy that replaced a removed hierarchy
if status is O or will replace a hierarchy if the date
of removal is in the future.
Example: Replacement: de
(for the hierarchy sub)
Used for: newsgroup
Mandatory: no
Repeatable: yes
Description: Name of the newsgroup or newsgroups that will replace a
removed newsgroup if status is X or will replace the
newsgroup if the date of removal is in the future.
Example: Replacement: bln.markt.arbeit
(for bln.jobs)
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Internet Draft Netnews Administration System May 22, 2000
Source
Name: Source
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: no
Description: Name of the organization/person that is responsible for
this hierarchy. SHOULD be a URL or email.
Example: Source: http://www.dana.de/mod/
(for the hierarchy de)
NOTE: This is for tracking the maintainer of an hierarchy
Control PGP key
Name: Ctl-PGP-Key
Used for: hierarchy
Mandatory: no
Inheritable: yes
Repeatable: yes
Description: PGP key (with additional information: key owner, key-id,
etc.) of the sender of control messages in this
hierarchy.
Comment: The exact format is described in section 6.7.
Example: Ctl-PGP-Key:
U de.admin.news.announce
B 1024
I D3033C99
L http://www.dana.de/mod/pgp/dana.asc
L ftp://ftp.isc.org/pub/pgpcontrol/PGPKEYS.gz
F 5B B0 52 88 BF 55 19 4F 66 7D C2 AE 16 26 28 25
V 2.6.3ia
K------BEGIN PGP PUBLIC KEY BLOCK-----
K-Version: 2.6.3ia
K-
K-mQCNEALZ+Xfm/WDCEMXM48gK1PlKG6TkV3SLbXt4CnzpGM0tOMa
K-HjlHqM1wEGUHD5hw/BL/heR5Tq+C5IEyXQQmYwkrgeVFMOz/rAQ
[...]
K-SDw+iQgAAtN6zrYOhHFBp+
K-VpvRovMz+lSOy9Zcsbs+5t8Pj9ZVAQyfxBkqD5A=
K-=Xwgc
K -----END PGP PUBLIC KEY BLOCK-----
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Moderator's PGP key
Name: Mod-PGP-Key
Used for: newsgroup
Mandatory: no
Repeatable: yes
Description: Public PGP key (with additional information: key owner,
key-id, etc) of this newsgroup's moderator.
Comment: The exact format is described in section 6.7
Example: see section 6.7
6.4. Status Indicators
The status indicator is used as a unique indicator of the status of a
hierarchy or newsgroup. The indicator is case-insensitive.
Indicator Type Description
-------------------- --------- -------------------------------------
Hierarchy-Complete hierarchy authorized, complete known hierarchy
Hierarchy-Incomplete hierarchy not completely known hierarchy
Hierarchy-Obsolete hierarchy obsolete hierarchy, should contain
only newsgroups with status "Removed"
Hierarchy-Unkown hierarchy no information available,
unknown hierarchy
Group-Post-Yes newsgroup posting allowed, unmoderated
Group-Post-No newsgroup posting not allowed
Group-Moderated newsgroup moderated group, articles must be
sent to the moderator
Group-Removed newsgroup deleted or renamed newsgroup, no
posting or transport
Group-Unknown newsgroup unknown group, no information
available
-------------------- --------- -------------------------------------
6.5. Newsgroup Types
A comprehensive overview about some characteristics of a newsgroup,
being a test group, a binary group and so on. The indicator is case-
insensitive.
Code Use of a newsgroup
---------- ----------------------------------------------------
Discussion discussion (text postings)
Binary (encoded) binary postings
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Internet Draft Netnews Administration System May 22, 2000
Sources source postings (e.g., comp.unix.sources)
Announce announcements, press releases, RfD/CfV
Test test postings, sometimes reflectors (e.g., de.test)
Robots automatic postings (e.g., comp.mail.maps)
Experiment experimental, other
---------- ----------------------------------------------------
6.6. Hierarchy Types
To describe a hierarchy the following codes are used. These flags are
used to mark some properties of a news hierarchy. The indicator is
case-insensitive.
Code Type of hierarchy
-------------- ---------------------------------------------------
Global international, global hierarchy
(e.g., the hierarchies comp, de, rec)
Regional regional hierarchy
(e.g., the hierarchies ba, bln, tor)
Alt alternative hierarchy, simpler rules for
creating a group, no formal structure
(e.g., the hierarchy alt)
Non-Commercial only for personal use, commercial use is prohibited
(e.g., the hierarchy de)
Commercial commercial use permitted
(e.g., the hierarchy biz)
Organization hierarchy bound to an organization
(e.g., the hierarchy gnu)
-------------- ---------------------------------------------------
6.7. PGP Keys
PGP keys for Ctrl-PGP-Key and Mod-PGP-Key are transmitted in the
following structure:
PGP-answer = "V" SP Version CRLF
"U" SP User-ID CRLF "B" SP Bits CRLF
"I" SP Key-ID CRLF
"F" SP Finger CRLF
*("L" SP Location CRLF)
*("K-" Keyblock CRLF) "K" SP Keyblock CRLF
Key Name Mandatory Description
--- --------- --------- --------------------------------------
K Keyblock yes public key block in ASCII armor format
[RFC2440]
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Internet Draft Netnews Administration System May 22, 2000
V Version yes PGP-Version
U User-ID no key user id
B Bits no number of bits
I Key-ID no key id, without leading "0x"
F Finger no fingerprint
L Location no URL that points to the public key
--- --------- --------- --------------------------------------
A hyphen following the code indicates that the block is continued on
the next line. In the last message row there must be white space
after the code, this is also true for a single line code.
Example
<-- HIER de
--> 611 ..
Name: de
Status: Hierarchy
[...]
Ctl-PGP-Key:
U de.admin.news.announce
B 1024
I D3033C99
L http://www.dana.de/mod/pgp/dana.asc
L ftp://ftp.fu-berlin.de/unix/news/pgpcontrol/PGPKEYS.gz
F 5B B0 52 88 BF 55 19 4F 66 7D C2 AE 16 26 28 25
V 2.6.3ia
K------BEGIN PGP PUBLIC KEY BLOCK-----
K-Version: 2.6.3ia
K-
K-mQCNAzGeB/YAAAEEALZ+Xfm/WDCEMXM48gK1PlKG6TkV3SLbXt4CnzpGMtOM
K-HjlHaU6Xco5ijAuqM1wEGUHD5hw/BL/heR5Tq+C5IEyXQQmYwkrgeVFMO/rA
[...]
K-SDw+Id0JPFO9AWOiQgAAtN6zrYOhHFBp+68h9k674Yg9IHqj3BWdRjJF6PKo
K-VpvRovMz+lSOy9Zcsbs+5t8Pj9ZVAQyfxBkqD5A=
K-=Xwgc
K -----END PGP PUBLIC KEY BLOCK-----
[...]
.
7. Specification of the NAS Protocol (UDP)
UDP is intended for reading programs (news reader), it is not in the
scope of this document and will be described in a separate paper.
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Internet Draft Netnews Administration System May 22, 2000
8. Security Considerations
Security issues are only vital for the server-server communication,
since we want a strict hierarchical model of the netnews
administration system. So we want to be sure that only authorized
clients connect to an authoritative server.
Every server has the possibility to deny some commands or the whole
connection based on the client's IP number.
Note: A stronger authentication scheme will be provided in a higher
protocol level.
9. References
[IANA-CS] IANA: Character Sets
ftp://ftp.isi.edu/in-notes/iana/assignments/character-sets
[IANA-MT] IANA: Media Types ftp://ftp.isi.edu/in-notes/iana/
assignments/media-types/media-types
[IANA-PN] IANA: Assigned Port Numbers
ftp://ftp.isi.edu/in-notes/iana/assignments/port-numbers
[RFC1036] Horton, M., and Adams, R., "Standard for Interchange of
USENET Messages", RFC 1036, AT&T Bell Laboratories/
Center for Seismic Studies, December 1987
[RFC1305] Mills, D.L., "Network Time Protocol", RFC 1305,
University of Delaware, March 1992
[RFC1700] Reynolds, J., and J. Postel, "Assigned Numbers", STD 2, RFC
1700, USC/ISI, October 1994.
[RFC1766] Alvestrand, H., "Tags for the Identification of
Languages", RFC 1766, March 1995.
[RFC2026] Bradner, S., "The Internet Standards Process - Revision 3",
RFC 2026, Harvard University, October 1996
[RFC2045] Freed, N. and Borenstein, N., "Multipurpose Internet Mail
Extensions (MIME)", RFC 2045, Innosoft/First Virtual,
November 1996
[RFC2119] Bradner, "Key words for use in RFCs to Indicate Requirement
Levels", RFC 2119, Harvard University, March 1997.
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Internet Draft Netnews Administration System May 22, 2000
[RFC2234] Crocker, Overell, "Augmented BNF for Syntax Specifications:
ABNF", RFC 2234, November 1997.
[RFC2277] Alvestrand, H., "IETF Policy on Character Sets and
Language", RFC 2277, January 1998
[RFC2440] Callas, J., Donnerhacke, L., Finney, H. and R. Thayer,
"OpenPGP Message Format", RFC 2240, November 1998.
[SON1036] Henry Spencer, "News Article Format and Transmission",
A Draft for an RFC 1036 Successor,
ftp://zoo.toronto.edu/pub/news.txt.Z
[USEFOR] USEFOR Working Group, "News Article Format"
draft-ietf-usefor-article-02
10. Author's Address
Philipp Grau, Vera Heinau, Heiko Schlichting
Freie Universitaet Berlin
ZEDAT, DFN-CIS
Fabeckstr. 32
14195 Berlin
Germany
Phone: +49 30 838-56583
Fax: +49 30 838-56721
Email: nas@cis.fu-berlin.de
WWW: http://nas.cis.fu-berlin.de/
Appendix A - Response Codes (Overview)
Code Description
---- ---------------------------------------------------------------
100 Command overview, Infomation command description (HELP)
101 Information about connection, client and server (INFO)
200 Greeting message (Connection Setup)
201 Termination of the connection (QUIT)
202 Returns current protocol level (VERS)
213 Valid data at the client side (GETP)
215 The client already has the current data (GETA)
300 Time in UTC (DATE)
302 Answer to an successful request (VERS)
400 Indicates that the server is not giving any information (INFO)
401 Permission denied (LIST, LSTR, HIER, DATA, GETL)
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402 Requested level too high, falling back to lower level (VERS)
404 Server currently out of service (Connection Setup)
410 Indicates that the server is not giving any information (HELP)
411 No package with that name (GETP, GETA)
430 Permission denied (GETP, GETA)
434 Client has no permission to talk to server (Connection Setup)
510 Syntax error (VERS)
511 Internal error (TIME)
530 Missing parameter (LIST, LSTR, HIER, DATA, GETP, GETA)
610 Regular answer with all requested data (LIST,LSTR)
611 Regular answer with all requested data (HIER)
612 Regular answer with all requested data (DATA)
613 Package data (GETP)
614 Lists all packages a server is authoritative for (GETL)
615 Regular answer with all requested data (GETA)
---- ---------------------------------------------------------------
Appendix B - Data Header for DATA and HIER Commands (Overview)
Name Mandatory Use Multiple Description
--------------- ---------- --- -------- ------------------------
Name yes H/N no Name of a hierarchy or
newsgroup (Start of a
new data block)
Status yes H/N no Status of hierarchy or
newsgroup
Followup no N no Group for followup
Description no H/N no Short description of a
hierarchy/newsgroup
Charter no H/N yes Charter-URL
Netiquette no H/N yes Netiquette-URL
FAQ no N yes FAQ-URL
Rules no H yes Administration rules URL
Ctl-Send-Adr no H yes Control email
Ctl-Newsgroup no H yes Control newsgroup
Mod-Wildcard no H no Moderator wildcard
Mod-Sub-Adr no N no Submission address
Mod-Adm-Adr no N yes Moderator's address
(email)
Mod-Group-Info no N yes Info-URL
Language no H/N yes Language
Charset no H/N yes Charset
Encoding no H/N yes Encoding
Newsgroup-Type no H/N yes Type of newsgroup
Hier-Type no H yes Type of hierarchy
Area no H yes Regional or
organizational area
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Name-Length no H no Total length of group
names
Comp-Length no H no Component length of
group names
Article-Length no H no Article length
Date-Create no H/N no Date of creation
Date-Delete no H/N no Date of removal
Replacement no H/N yes Successor
Source no H yes Source of data
Ctl-PGP-Key no H yes Control PGP key
Mod-PGP-Key no N yes Moderator's PGP key
--------------- ---------- --- -------- ------------------------
Expires November 27, 2000
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