draft-ietf-nntpext-base-02.txt   draft-ietf-nntpext-base-03.txt 
INTERNET DRAFT S. Barber INTERNET DRAFT S. Barber
Expires: February 5, 1998 Academ Consulting Services Expires: June 1, 1998 Academ Consulting Services
September 1997 December 1997
Network News Transport Protocol Network News Transport Protocol
draft-ietf-nntpext-base-02.txt draft-ietf-nntpext-base-03.txt
1. Status of this Document 1. Status of this Document
This document is an Internet-Draft. Internet-Drafts are This document is an Internet-Draft. Internet-Drafts are
working documents of the Internet Engineering Task Force working documents of the Internet Engineering Task Force
(IETF), its areas, and its working groups. Note that other (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet- groups may also distribute working documents as Internet-
Drafts. Drafts.
Internet-Drafts are draft documents valid for a maximum of six Internet-Drafts are draft documents valid for a maximum of six
skipping to change at line 54 skipping to change at page 1, line 55
This document specifies the Network News Transport Protocol This document specifies the Network News Transport Protocol
(NNTP), which is used for the distribution, inquiry, (NNTP), which is used for the distribution, inquiry,
retrieval, and posting of Usenet articles using a reliable retrieval, and posting of Usenet articles using a reliable
stream-based mechanism. For news reading clients, NNTP enables stream-based mechanism. For news reading clients, NNTP enables
retrieval of news articles that are stored in a central retrieval of news articles that are stored in a central
database, giving subscribers the ability to select only those database, giving subscribers the ability to select only those
articles they wish to read. articles they wish to read.
The netnews model provides for indexing, cross-referencing, The netnews model provides for indexing, cross-referencing,
and expiration of aged messages. For server-to-server and expiration of aged messages. For server-to-server
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interaction, NNTP is designed for efficient transmission of interaction, NNTP is designed for efficient transmission of
Usenet articles over a reliable full duplex communication Usenet articles over a reliable full duplex communication
method. method.
Every attempt is made to insure that the protocol Every attempt is made to insure that the protocol
specification in this document is compatible with the version specification in this document is compatible with the version
specified in RFC 977[1]. specified in RFC 977[1]. However, this version does not
support the ill-defined SLAVE command and permits four digit
years to be specified in the NEWNEWS and NEWGROUPS commands.
It changes the default character set to UTF-8[2] instead of
US-ASCII[3]. It also makes extends the newsgroup name matching
capabilities already documented in RFC 977.
Generally, new functionality is available using new keywords. Generally, new functionality is available using new keywords.
Part of that new functionality involves a mechanism to Part of that new functionality involves a mechanism to
discover what new functionality is available to clients from a discover what new functionality is available to clients from a
server. server.
This mechanism can also be used to add more functionality as This mechanism can also be used to add more functionality as
needs merit such additions. needs merit such additions.
In this document, the words that are used to define the The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL
significance of each particular requirement are capitalized. NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described
These words are: in RFC 2119[4].
. "MUST"
This word or the adjective "REQUIRED" means that the item is
an absolute requirement of the specification.
. "SHOULD"
This word or the adjective "RECOMMENDED" means that there may
exist valid reasons in particular circumstances to ignore this
item, but the full implications should be understood and the
case carefully weighed before choosing a different course.
. "MAY"
This word or the adjective "OPTIONAL" means that this item is
truly optional. One vendor may choose to include the item
because a particular marketplace requires it or because it
enhances the product, for example; another vendor may omit the
same item.
An implementation is not compliant if it fails to satisfy one An implementation is not compliant if it fails to satisfy one
or more of the MUST requirements for this protocol. An or more of the MUST requirements for this protocol. An
implementation that satisfies all the MUST and all the SHOULD implementation that satisfies all the MUST and all the SHOULD
requirements for its protocols is said to be "unconditionally requirements for its protocols is said to be "unconditionally
compliant"; one that satisfies all the MUST requirements but compliant"; one that satisfies all the MUST requirements but
not all the SHOULD requirements for NNTP is said to be not all the SHOULD requirements for NNTP is said to be
"conditionally compliant". "conditionally compliant".
For the remainder of this memo, the term "client host" refers For the remainder of this memo, the term "client host" refers
to a host making use of the NNTP service, while the term to a host making use of the NNTP service, while the term
"server host" refers to a host that offers the NNTP service. "server host" refers to a host that offers the NNTP service.
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4. Basic Operation. 4. Basic Operation.
Every NNTP session MUST involve the following in this order: Every NNTP session MUST involve the following in this order:
CONNECTION CONNECTION
GREETING GREETING
DISCONNECTION DISCONNECTION
Other steps may occur between the GREETING and DISCONNECTION Other steps may occur between the GREETING and DISCONNECTION
step. They are: step. They are:
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The client host and server host then SHOULD then exchange The client host and server host then SHOULD then exchange
commands and responses (respectively) until the connection is commands and responses (respectively) until the connection is
closed or aborted. This final step is called the DISCONNECTION closed or aborted. This final step is called the DISCONNECTION
step. step.
If there is a CONCLUSION step, it MUST immediately precede the If there is a CONCLUSION step, it MUST immediately precede the
DISCONNECTION step. There MUST be only one CONNECTION, DISCONNECTION step. There MUST be only one CONNECTION,
CONCLUSION and DISCONNECTION step for each NNTP session. All CONCLUSION and DISCONNECTION step for each NNTP session. All
other steps MAY be repeated as needed. other steps MAY be repeated as needed.
The default character set for all NNTP commands is US- The character set for all NNTP commands is UTF-8. Commands in
ASCII[2]. Commands in the NNTP MUST consist of a case- the NNTP MUST consist of a US-ASCII case-insensitive keyword,
insensitive keyword, which MAY be followed by one or more which MAY be followed by one or more arguments. All commands
arguments. All commands MUST be terminated by a CRLF pair. MUST be terminated by a US-ASCII CRLF pair. Multiple commands
Multiple commands MUST not be permitted on the same line. MUST NOT be permitted on the same line. Keywords MUST consist
Keywords MUST consist of printable US-ASCII characters. of printable US-ASCII characters. Unless otherwise noted
Unless otherwise noted elsewhere in this document, Arguments elsewhere in this document, Arguments SHOULD consist of
SHOULD consist of printable US-ASCII characters. Keywords and printable US-ASCII characters. Keywords and arguments MUST be
arguments MUST be each separated by one or more SPACE or TAB each separated by one or more US-ASCII SPACE or US-ASCII TAB
characters. Keywords MUST be at least three characters and characters. Keywords MUST be at least three US-ASCII
MUST NOT exceed 12 characters. Command lines MUST not exceed characters and MUST NOT exceed 12 US-ASCII characters.
512 characters, which includes the terminating CRLF pair. Command lines MUST NOT exceed 512 octets, which includes the
terminating US-ASCII CRLF pair.
Each response MUST start with a three-digit status indicator Each response MUST start with a three-digit status indicator
that is sufficient to distinguish all responses. Responses to that is sufficient to distinguish all responses. Responses to
certain commands MAY be multi-line. In these cases, which are certain commands MAY be multi-line. In these cases, which are
clearly indicated below, after sending the first line of the clearly indicated below, after sending the first line of the
response and a CRLF, any additional lines are sent, each response and a US-ASCII CRLF, any additional lines are sent,
each terminated by a US-ASCII CRLF pair. When all lines of the
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terminated by a CRLF pair. When all lines of the response have of a termination octet (US-ASCII decimal code 046, ".") and a
been sent, a final line MUST be sent, consisting of a US-ASCII CRLF pair. If any line of the multi-line response
termination octet (ASCII decimal code 046, ".") and a CRLF begins with the termination octet, the line MUST be "byte-
pair. If any line of the multi-line response begins with the stuffed" by pre-pending the termination octet to that line of
termination octet, the line MUST be "byte-stuffed" by pre- the response. Hence, a multi-line response is terminated with
pending the termination octet to that line of the response. the five octets "CRLF.CRLF" (in US-ASCII). When examining a
Hence, a multi-line response is terminated with the five multi-line response, the client MUST check to see if the line
octets "CRLF.CRLF". When examining a multi-line response, the begins with the termination octet. If so and if octets other
client MUST check to see if the line begins with the than US-ASCII CRLF follow, the first octet of the line (the
termination octet. If so and if octets other than CRLF follow, termination octet) MUST be stripped away. If so and if US-
the first octet of the line (the termination octet) MUST be ASCII CRLF immediately follows the termination character, then
stripped away. If so and if CRLF immediately follows the the response from the NNTP server is ended and the line
termination character, then the response from the NNTP server containing ".CRLF" (in US-ASCII) MUST NOT considered part of
is ended and the line containing ".CRLF" MUST not considered the multi-line response.
part of the multi-line response.
A NNTP server MAY have an inactivity autologout timer. Such a A NNTP server MAY have an inactivity autologout timer. Such a
timer MUST be of at least 10 minutes duration. The receipt of timer MUST be of at least three minutes duration. The receipt
any command from the client during that interval should of any command from the client during that interval should
suffice to reset the autologout timer. When the timer suffice to reset the autologout timer. When the timer
expires, the server should close the TCP connection without expires, the server should close the TCP connection without
sending any response to the client. sending any response to the client.
4.1 Responses Codes 4.1 Responses Codes
Each response MUST begin with a three-digit response code. Each response MUST begin with a three-digit response code.
These are status reports from the server and indicate the These are status reports from the server and indicate the
response to the last command received from the client. response to the last command received from the client.
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x0x - Connection, setup, and miscellaneous messages x0x - Connection, setup, and miscellaneous messages
x1x - Newsgroup selection x1x - Newsgroup selection
x2x - Article selection x2x - Article selection
x3x - Distribution functions x3x - Distribution functions
x4x - Posting x4x - Posting
x5x - Authentication and Authorization x5x - Authentication and Authorization
x8x - Nonstandard (private implementation) extensions x8x - Nonstandard (private implementation) extensions
x9x - Debugging output x9x - Debugging output
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The exact response codes that MUST be expected from each The exact response codes that MUST be expected from each
command are detailed in the description of the keyword that is command are detailed in the description of the keyword that is
the first part of the command. In addition, below is listed a the first part of the command. In addition, below is listed a
general set of response codes that MAY be received at any general set of response codes that MAY be received at any
time. time.
Certain status responses contain parameters such as numbers Certain status responses contain parameters such as numbers
and names. The number and type of such parameters SHOULD be and names. In those cases, the number and type of such
fixed for each response code to simplify interpretation of the parameters MUST be fixed for each response code to simplify
response. interpretation of the response. In all other cases, the client
MUST only use the response code itself to determine the nature
of the response.
Parameters MUST be separated from the numeric response code Parameters MUST be separated from the numeric response code
and from each other by a single space. All numeric parameters and from each other by a single US-ASCII space. All numeric
MUST be in base 10 (decimal) format, and may have leading parameters MUST be in base 10 (decimal) format, and may have
zeros. All string parameters MUST begin after the separating leading zeros. All string parameters MUST begin after the
space, and MUST end before the following separating space or separating space, and MUST end before the following separating
the CR-LF pair at the end of the line. (Therefore, string space or the US-ASCII CRLF pair at the end of the line.
parameters MUST not contain spaces.) All text, if any, in the (Therefore, string parameters MUST NOT contain US-ASCII
response which is not a parameter of the response must follow spaces.) All text, if any, in the response which is not a
and be separated from the last parameter by a space. Also, parameter of the response must follow and be separated from
note that the text following a response number may vary in the last parameter by a US-ASCII space. Also, note that the
different implementations of the server. The 3-digit numeric text following a response number may vary in different
code should be used to determine what response was sent. implementations of the server. The 3-digit numeric code should
be used to determine what response was sent.
Response codes not specified in this standard MAY be used for Response codes not specified in this standard MAY be used for
any installation-specific additional commands also not any installation-specific additional commands also not
specified. These SHOULD be chosen to fit the pattern of x8x specified. These SHOULD be chosen to fit the pattern of x8x
specified above. (Note that debugging is provided for specified above. (Note that debugging is provided for
explicitly in the x9x response codes.) explicitly in the x9x response codes.)
The use of unspecified response codes for a standard command The use of unspecified response codes for a standard command
is prohibited. is prohibited.
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(For example, response code 290 could be used to acknowledge a (For example, response code 290 could be used to acknowledge a
remote debugging request.) remote debugging request.)
A server MUST respond to an unrecognized, unimplemented, or A server MUST respond to an unrecognized, unimplemented, or
syntactically invalid command with a negative status indicator syntactically invalid command with a negative status indicator
(response codes of the form 5XX). A server MUST respond to a (response codes of the form 5XX). A server MUST respond to a
command issued when the session is in an incorrect state by command issued when the session is in an incorrect state by
responding with a negative status indicator. This may be from responding with a negative status indicator. This may be from
either the 4XX or 5XX group as appropriate. either the 4XX or 5XX group as appropriate.
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5. The WILDMAT format 5. The WILDMAT format
The WILDMAT format[3] was first developed by Rich Salz based The WILDMAT format[5] was first developed by Rich Salz based
on the format used in the UNIX "find" command to articulate on the format used in the UNIX "find" command to articulate
file names. It was developed to provide a uniform mechanism file names. It was developed to provide a uniform mechanism
for matching patterns in the same manner that the UNIX shell for matching patterns in the same manner that the UNIX shell
matches filenames. Patterns are implicitly anchored at the matches filenames. Patterns are implicitly anchored at the
beginning and end of each string when testing for a match. beginning and end of each string when testing for a match.
There are five pattern-matching operations other than a strict There are five pattern-matching operations other than a strict
one-to-one match between the pattern and the source to be one-to-one match between the pattern and the source to be
checked for a match. The first is an asterisk (*) to match any checked for a match. The first is an asterisk (*) to match any
sequence of zero or more characters. The second is a question sequence of zero or more UTF-8 characters. The second is a
mark (?) to match any single character. The third specifies a question mark (?) to match any single UTF-8 character. The
specific set of characters. The set is specified as a list of third specifies a specific set of characters. The set is
characters, or as a range of characters where the beginning specified as a list of characters, or as a range of characters
and end of the range are separated by a minus (or dash) where the beginning and end of the range are separated by a
character, or as any combination of lists and ranges. The dash minus (or dash) character, or as any combination of lists and
can also be included in the set as a character if it is the ranges. The dash can also be included in the set as a
beginning or end of the set. This set is enclosed in square character it if is the beginning or end of the set. This set
brackets. The close square bracket (]) may be used in a set if is enclosed in square brackets. The close square bracket (])
it is the first character in the set. The fourth operation is may be used in a set if it is the first character in the set.
the same as the logical not of the third operation and is The fourth operation is the same as the logical not of the
specified the same way as the third with the addition of a third operation and is specified the same way as the third
caret character (^) at the beginning of the test string just with the addition of a caret character (^) at the beginning of
inside the open square bracket. The final operation uses the the test string just inside the open square bracket. The final
backslash character to invalidate the special meaning of the operation uses the backslash character to invalidate the
open square bracket ([), the asterisk, backslash or the special meaning of the open square bracket ([), the asterisk,
question mark. Two backslashes in sequence will result in the backslash or the question mark. Two backslashes in sequence
evaluation of the backslash as a character with no special will result in the evaluation of the backslash as a character
meaning. with no special meaning.
5.1 Examples 5.1 Examples
a) [^]-] -- matches any single character other than a a) [^]-] -- matches any single character other than a
close square bracket or a minus sign/dash. close square bracket or a minus sign/dash.
b) *bdc -- matches any string that ends with the string b) *bdc -- matches any string that ends with the string
"bdc" including the string "bdc" (without quotes). "bdc" including the string "bdc" (without quotes).
c) [0-9a-zA-Z] -- matches any single printable alphanumeric c) [0-9a-zA-Z] -- matches any single printable
ASCII character. alphanumeric ASCII character.
d) a??d -- matches any four character string which d) a??d -- matches any four character string which
begins with a and ends with d. begins with a and ends with d.
6. Format for Keyword Descriptions 6. Format for Keyword Descriptions
On the following pages are descriptions of each keyword On the following pages are descriptions of each keyword
recognized by the NNTP server and the responses that will be recognized by the NNTP server and the responses that will be
returned by those commands. These keywords are grouped by the returned by those commands. These keywords are grouped by the
functional step in which they are used. functional step in which they are used.
Each keyword is shown in upper case for clarity, although case Each keyword is shown in upper case for clarity, although case
is ignored in the interpretation of commands by the NNTP is ignored in the interpretation of commands by the NNTP
server. Any parameters are shown in lower case. A parameter server. Any parameters are shown in lower case. A parameter
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shown in [square brackets] is optional. For example, [GMT] shown in [square brackets] is optional. For example, [GMT]
indicates that the triglyph GMT may present or omitted. A indicates that the triglyph GMT may present or omitted. A
parameter that may be repeated is followed by an ellipsis. parameter that may be repeated is followed by an ellipsis.
Mutually exclusive parameters are separated by a vertical bar Mutually exclusive parameters are separated by a vertical bar
(|) character. For example, ggg|<message-id> indicates that a (|) character. For example, ggg|<message-id> indicates that a
group name or a <message-id> may be specified, but not both. group name or a <message-id> may be specified, but not both.
Some parameters may be case or language specific. See RFC Some parameters may be case or language specific. See RFC
1036[4] for these details. 1036[6] for these details.
In addition, certain commands make use of a pattern for In addition, certain commands make use of a pattern for
selection of multiple news groups. The pattern in all cases is selection of multiple news groups. The pattern in all cases is
based on the WILDMAT format introduced by Rich Salz in 1986. based on the WILDMAT format introduced by Rich Salz in 1986.
Arguments expected to be in wildmat format will be represented Arguments expected to be in wildmat format will be represented
by the string wildmat. This format is discussed in detail in by the string wildmat. This format is discussed in detail in
section 5 of this memo. section 5 of this memo.
7. The GREETING Step 7. The GREETING Step
7.1 Initial Connection 7.1 Initial Connection
There is no keyword presented by the client upon initial There is no keyword presented by the client upon initial
connection to the server. The server MUST present an connection to the server. The server MUST present an
appropriate response code as a greeting to the client. This appropriate response code as a greeting to the client. This
response informs the client about what steps the client should response informs the client about what steps the client should
take to reach the news exchange step. take to reach the news exchange step.
The server must present a 200 greeting code if the client is The server must present a 200 greeting code if the client is
authorized to post articles through the use of the POST keyword authorized to post articles though the use of the POST keyword
on this server. on this server.
The server must present a 201 greeting code if the client is The server must present a 201 greeting code if the client is
not authorized to post articles using the POST keyword, but no not authorized to post articles using the POST keyword, but no
other authentication is required. other authentication is required.
The server must present a 205 greeting code if the client is The server must present a 205 greeting code if the client is
required to present authentication before it is permitted to required to present authentication before it is permitted to
use any keywords available in the news exchange step. use any keywords available in the news exchange step.
The server must present a 502 greeting code if the client is The server must present a 502 greeting code if the client is
not permitted under any circumstances from interacting with not permitted under any circumstances from interacting with
the server. The server should immediately close the connection the server. The server should immediately close the connection
with the client after presenting this code. with the client after presenting this code.
In all other cases, the server must present a 400 greeting In all other cases, the server must present a 400 greeting
code. code.
7.1.1 MODE READER 7.1.1 MODE READER
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MODE READER MODE READER
MODE READER MAY be used by the client to indicate to the MODE READER MAY be used by the client to indicate to the
server that it is a news reading client. This command may be server that it is a news reading client. This command may be
entered at any time. The server must present a greeting code entered at any time. The server must present a greeting code
(as described in section 7.1) appropriate to the server's (as described in section 7.1.1.1) appropriate to the server's
ability to provide service to this client in this mode. ability to provide service to this client in this mode.
7.1.1.1 Responses 7.1.1.1 Responses
200 Hello, you can post 200 Hello, you can post
201 Hello, you can't post 201 Hello, you can't post
205 Authentication required 205 Authentication required
400 Service temporarily unavailable 400 Service temporarily unavailable
502 Service unavailable 502 Service unavailable
8. The CAPABILITIES DISCOVERY Step 8. The CAPABILITIES DISCOVERY Step
A client NNTP supporting NNTP service extensions should query A client NNTP supporting NNTP service extensions should query
a server early in the session for extensions session by a server early in the session for extensions session by
issuing the LIST EXTENSIONS command. If the NNTP server issuing the LIST EXTENSIONS command. If the NNTP server
supports the NNTP service extensions it MUST give a successful supports the NNTP service extensions it MUST give a successful
response (see section 8.1.1), a failure response (see section response (see section 8.1.1), a failure response (see section
8.1.2), or an error response (see section 8.1.3). If the NNTP 8.1.2), or an error response (see section 8.1.3). If the NNTP
server does not support any NNTP service extensions, it MUST server does not support any NNTP service extensions, it MUST
generate an error response (see section 8.1.4). generate an error response (see section 8.1.4).
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If successful, the server NNTP MUST respond with code 202. On If successful, the server NNTP MUST respond with code 202. On
failure, the server NNTP MUST respond with code 503. On error, failure, the server NNTP MUST respond with code 503. On error,
the server NNTP MUST respond with one of codes 400, 402, 500 the server NNTP MUST respond with one of codes 400, 402, 500
and 501. and 501.
This command MAY be issued at anytime during a session. It is This command MAY be issued at anytime during a session. It is
not required that the client issues this command before not required that the client issues this command before
attempting to make use of any extension. The response attempting to make use of any extension. The response
generated by this command MAY change during a session because generated by this command MAY change during a session because
of other state information (e.g. authentication or server of other state information (e.g. authentication or server
administration). However, a client NNTP MUST not cache (for administration). However, a client NNTP MUST NOT cache (for
use in another session) any information returned if the LIST use in another session) any information returned if the LIST
EXTENSIONS command succeeds. That is, a client NNTP MUST issue EXTENSIONS command succeeds. That is, a client NNTP MUST issue
the LIST EXTENSIONS command at least once during each session the LIST EXTENSIONS command at least once during each session
to get the current and correct information concerning to get the current and correct information concerning
available extensions during that session. available extensions during that session.
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8.1.1 Successful response 8.1.1 Successful response
If the server NNTP implements and is able to perform the LIST If the server NNTP implements and is able to perform the LIST
EXTENSIONS command, it MUST return code 202. EXTENSIONS command, it MUST return code 202.
This response MUST be a multi-line reply. Each line of the This response MUST be a multi-line reply. Each line of the
response MUST contain a supported keyword and, optionally, one response MUST contain a supported keyword and, if required,
or more parameters. The list MUST end with a period on a line one or more verbs that fully specify a single supported
by itself. extension. Extensions that are specified by multiple keywords
or multiple keyword/verb combination MUST have each of those
keywords and/or keyword/verb combinations in the list to
correctly and fully indicate support for a particular
extension. The list MUST end with a period on a line by
itself.
Although LIST EXTENSIONS keywords may be specified in upper, Although LIST EXTENSIONS keywords may be specified in upper,
lower, or mixed case, they must always be recognized and lower, or mixed case, they must always be recognized and
processed in a case-insensitive manner. processed in a case-insensitive manner.
8.1.2 Failure response 8.1.2 Failure response
If for some reason the server NNTP is unable to list the If for some reason the server NNTP is unable to list the
service extensions it supports, it MUST return code 503. service extensions it supports, it MUST return code 503.
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If the server NNTP determines that the NNTP service is no If the server NNTP determines that the NNTP service is no
longer available (e.g., due to imminent system shutdown), it longer available (e.g., due to imminent system shutdown), it
must return code 400. must return code 400.
In the case of an error response, the client NNTP should issue In the case of an error response, the client NNTP should issue
the QUIT command (see section 11.1). the QUIT command (see section 11.1).
8.1.4 Responses from servers without extensions 8.1.4 Responses from servers without extensions
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A server NNTP that conforms to this memo but does not support A server NNTP that conforms to this memo but does not support
the extensions specified here will not recognize the LIST the extensions specified here will not recognize the LIST
EXTENSIONS command and MUST consequently return code 500 or EXTENSIONS command and MUST consequently return code 500 or
code 501. The server NNTP SHALL stay in the same state after code 501. The server NNTP SHALL stay in the same state after
returning this code. The client NNTP may try the extensions returning this code. The client NNTP may try the extensions
either as the need arises or configure itself for the basic either as the need arises or configure itself for the basic
NNTP functionality defined in this document. NNTP functionality defined in this document.
8.1.5 Responses from improperly implemented servers 8.1.5 Responses from improperly implemented servers
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the authentication step, the server MUST respond with a 350 the authentication step, the server MUST respond with a 350
response. The client MUST then send AUTHINFO PASS followed by response. The client MUST then send AUTHINFO PASS followed by
one or more space characters followed by the password. If the one or more space characters followed by the password. If the
username/password combination is valid or no password is username/password combination is valid or no password is
required, the server MUST return a 250 response and the client required, the server MUST return a 250 response and the client
should then retry the original command to which the server should then retry the original command to which the server
responded with the 450 response. The command SHALL then be responded with the 450 response. The command SHALL then be
processed by the server normally. If the combination is not processed by the server normally. If the combination is not
valid, the server MUST return a 452 response. valid, the server MUST return a 452 response.
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If the server returns 501, this means that the authenticator If the server returns 501, this means that the authenticator
invocation was syntactically incorrect, or that this form of invocation was syntactically incorrect, or that this form of
AUTHINFO is not supported. AUTHINFO is not supported.
If the requested authenticator capability is not found or If the requested authenticator capability is not found or
there is some other unspecified server program error, the there is some other unspecified server program error, the
server MUST return the 503 response code. server MUST return the 503 response code.
9.1.1.1 Responses 9.1.1.1 Responses
250 Authorization accepted 250 Authorization accepted
350 Continue with authorization sequence 350 Continue with authorization sequence
450 Authorization required for this command 450 Authorization required for this command
452 Authorization rejected 452 Authorization rejected
501 Command not supported or Command Syntax Error 501 Command not supported or Command Syntax Error
502 Program error, function not performed 503 Program error, function not performed
9.1.2 AUTHINFO GENERIC 9.1.2 AUTHINFO GENERIC
AUTHINFO GENERIC authenticator arguments... AUTHINFO GENERIC authenticator arguments...
AUTHINFO GENERIC is used to identify a specific entity to the AUTHINFO GENERIC is used to identify a specific entity to the
server using arbitrary authentication or identification server using arbitrary authentication or identification
protocols. The desired protocol is indicated by the protocols. The desired protocol is indicated by the
authenticator parameter, and any number of parameters can be authenticator parameter, and any number of parameters can be
passed to the authenticator. passed to the authenticator.
When authorization is required, the server will send a 350 When authorization is required, the server will send a 450
response requesting authorization from the client. response requesting authorization from the client.
The client should enter AUTHINFO GENERIC followed by the The client should enter AUTHINFO GENERIC followed by the
authenticator name and the arguments if any. The authenticator name and the arguments if any. The
authenticator and arguments must not contain the sequence authenticator and arguments must not contain the sequence
"..". "..".
The server will attempt to engage the server end The server will attempt to engage the server end
authenticator; similarly, the client should engage the client authenticator; similarly, the client should engage the client
end authenticator. The server end authenticator will then end authenticator. The server end authenticator will then
initiate authentication using the NNTP sockets (if appropriate initiate authentication using the NNTP sockets (if appropriate
for that authentication protocol), using the protocol for that authentication protocol), using the protocol
specified by the authenticator name. These authentication specified by the authenticator name. These authentication
protocols are not included in this document, but are similar protocols are not included in this document, but are similar
in structure to those referenced in RFC 1731[5] for the IMAP-4 in structure to those referenced in RFC 1731[7] for the IMAP-4
protocol. protocol.
If the server returns 501, this means that the authenticator If the server returns 501, this means that the authenticator
invocation was syntactically incorrect, or that AUTHINFO invocation was syntactically incorrect, or that AUTHINFO
GENERIC is not supported. The client should retry using the GENERIC is not supported. The client should retry using the
regular AUTHINFO command. AUTHINFO GENERIC command.
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If the requested authenticator capability is not found or If the requested authenticator capability is not found or
there is some other unspecified server program error, the there is some other unspecified server program error, the
server returns the 503 response code. server returns the 503 response code.
The authenticators converse using their protocol until The authenticators converse using their protocol until
complete. If the authentication succeeds, the server complete. If the authentication succeeds, the server
authenticator will terminate with a 250, and the client can authenticator will terminate with a 250, and the client can
continue by reissuing the command that prompted the 350. If continue by reissuing the command that prompted the 350. If
the authentication fails, the server will respond with a 452. the authentication fails, the server will respond with a 452.
The client must provide authentication when requested by the The client must provide authentication when requested by the
server. The server may request authentication at any time. server. The server may request authentication at any time.
Servers may request authentication more than once during a Servers may request authentication more than once during a
single session. single session.
When the server authenticator completes, it provides to the When the server authenticator completes, it provides to the
server (by a mechanism herein undefined) the email address of server (by a mechanism herein undefined) the email address of
the user, and potentially what the user is allowed to access. the user, and potentially what the user is allowed to access.
Once authenticated, the server shall generate a Sender: line Once authenticated and if the email address provided by the
using the email address provided by the authenticator if it authenticator does not match the user-supplied From: line, the
does not match the user-supplied From: line. Additionally, the server SHALL insert a Sender: line into any posted articles
server should log the event, including the user's using the email address provided by the authenticator.
authenticated email address (if available). This will provide
a means by which subsequent statistics generation can Additionally, the server should log the event, including the
user's authenticated email address (if available). This will
provide a means by which subsequent statistics generation can
associate news group references with unique entities - not associate news group references with unique entities - not
necessarily by name. necessarily by name.
9.1.2.1 Responses 9.1.2.1 Responses
250 Authorization accepted 250 Authorization accepted
350 Continue with authorization sequence
450 Authorization required for this command 450 Authorization required for this command
452 Authorization rejected 452 Authorization rejected
501 Command not supported or Command Syntax Error 501 Command not supported or Command Syntax Error
502 Program error, function not performed 503 Program error, function not performed
nnn authenticator-specific protocol. nnn authenticator-specific protocol.
9.1.3 Transition Issues 9.1.3 Transition Issues
The implementations of AUTHINFO commonly in use prior to the The implementations of AUTHINFO commonly in use prior to the
release of this memo have a difference response code set. The release of this memo have a different response code set. The
code 281 was used in place of 250, 381 was used in place of code 281 was used in place of 250, 381 and 480 were used in
350, 480 was used in place of 450 and 482 was used in place of place of 450 and 482 and 502 were used in place of 452. Client
452. Client coded to be compliant with this spec may also want coded to be compliant with this spec may also want to be able
to be able to accommodate the older codes to lessen the impact to accommodate the older codes to lessen the impact of the
of the transition to this specification. transition to this specification.
10. The NEWS EXCHANGE Step 10. The NEWS EXCHANGE Step
During this step, two basic types of transactions occur: During this step, two basic types of transactions occur:
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article retrieval from the server and article posting to the article retrieval from the server and article posting to the
server. server.
10.1 Article Retrieval 10.1 Article Retrieval
News reading clients have available a variety of mechanisms to News reading clients have available a variety of mechanisms to
retrieve articles via NNTP. The news articles are stored and retrieve articles via NNTP. The news articles are stored and
indexed using three types of keys. One key is the message id indexed using three types of keys. One key is the message id
of an article. According to RFC 1036, this identifier should of an article. According to RFC 1036, this identifier should
be globally unique. Another key is composed of the news group be globally unique. Another key is composed of the news group
skipping to change at line 639 skipping to change at page 13, line 4
article with that number within a particular news group), but article with that number within a particular news group), but
is not required to be globally unique. Additionally, because is not required to be globally unique. Additionally, because
the same article can be cross-posted to multiple news groups, the same article can be cross-posted to multiple news groups,
there may be multiple keys that point to the same article on there may be multiple keys that point to the same article on
the same server. The final key is the arrival timestamp, the same server. The final key is the arrival timestamp,
giving the time that the article arrived at the server. giving the time that the article arrived at the server.
The server MUST ensure that article numbers are issued in The server MUST ensure that article numbers are issued in
order of arrival timestamp; that is, articles arriving later order of arrival timestamp; that is, articles arriving later
MUST have higher numbers than those that arrive earlier. The MUST have higher numbers than those that arrive earlier. The
server SHOULD allocate the first unused number to each new server SHOULD allocate the next sequential unused number to
article. each new article.
Article numbers MUST lie between 1 and 4,294,967,295 Article numbers MUST lie between 1 and 4,294,967,295
inclusive. The client and server SHOULD NOT use leading zeroes inclusive. The client and server SHOULD NOT use leading zeroes
in specifying article numbers, and MUST NOT use more than 16 in specifying article numbers, and MUST NOT use more than 16
digits. In some situations, the value zero replaces an article digits. In some situations, the value zero replaces an article
number to show some special situation number to show some special situation. One case involves
responses to the ARTICLE, STAT, BODY and HEAD commands where a
<message-id> is specified as the argument. In those cases, the
"current article pointer" is not changed.
10.1.1 Article Retrieval by News Group Name and Article Number 10.1.1 Article Retrieval by News Group Name and Article Number
The following commands are used to set the current news group The following commands are used to set the current news group
name and the "current article pointer" which is used by other name and the "current article pointer" which is used by other
commands for article retrieval. commands for article retrieval.
10.1.1.1 GROUP 10.1.1.1 GROUP
GROUP ggg GROUP ggg
The required parameter ggg is the name of the news group to be The required parameter ggg is the name of the news group to be
selected (e.g. "news.software.b"). A list of valid news groups selected (e.g. "news.software.b"). A list of valid news groups
may be obtained by using the LIST keyword. See section 10.4 for may be obtained by using the LIST keyword. See section 10.4
more information on the LIST keyword. for more information on the LIST keyword.
The successful selection response will return the article The successful selection response will return the article
numbers of the first and last articles in the group at the numbers of the first and last articles in the group at the
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moment of selection (these numbers are referred to as the moment of selection (these numbers are referred to as the
"reported low water mark" and the "reported high water mark"), "reported low water mark" and the "reported high water mark"),
and an estimate of the number of articles on file in the and an estimate of the number of articles on file in the
group. group.
If the group is not empty, the estimate MUST be at least the If the group is not empty, the estimate MUST be at least the
actual number of articles available, and MUST be no greater actual number of articles available, and MUST be no greater
than one more than the difference between the reported low and than one more than the difference between the reported low and
high water marks. (Some implementations will actually count high water marks. (Some implementations will actually count
the number of articles on file. Others will just subtract the the number of articles on file. Others will just subtract the
skipping to change at line 718 skipping to change at page 14, line 34
whenever a subsequent GROUP command for the same news group is whenever a subsequent GROUP command for the same news group is
issued, either by the same client or a different client, the issued, either by the same client or a different client, the
reported low water mark in the response MUST be no less than reported low water mark in the response MUST be no less than
that in any previous response for that news group sent to any that in any previous response for that news group sent to any
client. The client may make use of the low water mark to client. The client may make use of the low water mark to
remove all remembered information about articles with lower remove all remembered information about articles with lower
numbers, as these will never recur. This includes the numbers, as these will never recur. This includes the
situation when the high water mark is one less than the low situation when the high water mark is one less than the low
water mark. water mark.
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No similar assumption can be made about the high water mark, No similar assumption can be made about the high water mark,
as this can decrease if an article is removed, and then as this can decrease if an article is removed, and then
increase again if it is reinstated or if new articles arrive. increase again if it is reinstated or if new articles arrive.
When a valid group is selected by means of this command, the When a valid group is selected by means of this command, the
internally maintained "current article pointer" MUST be set to internally maintained "current article pointer" MUST be set to
the first article in the group and the name of the current the first article in the group and the name of the current
news group MUST be set to the selected news group name. If an news group MUST be set to the selected news group name. If an
invalid group is specified, the previously selected group and invalid group is specified, the previously selected group and
article MUST remain selected. If an empty news group is article MUST remain selected. If an empty news group is
selected, the "current article pointer" is in an indeterminate selected, the "current article pointer" is in an indeterminate
state and MUST not be used. state and MUST NOT be used.
The GROUP keyword MUST be used by a client and a successful The GROUP keyword MUST be used by a client and a successful
response received before the any other command is used that response received before the any other command is used that
depends on having the "current article pointer" be valid. depends on having the "current article pointer" be valid.
10.1.1.1.1 Responses 10.1.1.1.1 Responses
211 n f l s group selected 211 n f l s group selected
(n = estimated number of articles in group, f = first (n = estimated number of articles in group, f = first
article number in the group, l = last article number in article number in the group, l = last article number in
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multiple LAST and NEXT commands MAY not be consistent over the multiple LAST and NEXT commands MAY not be consistent over the
life of a particular NNTP session. life of a particular NNTP session.
The internally-maintained "current article pointer" MUST be The internally-maintained "current article pointer" MUST be
set by this command. set by this command.
A response indicating the current article number and a A response indicating the current article number and a
message-id string MUST be returned. No text is sent in message-id string MUST be returned. No text is sent in
response to this command. response to this command.
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10.1.1.2.1 Responses 10.1.1.2.1 Responses
223 n a article retrieved - request text separately (n = 223 n a article retrieved - request text separately (n =
article number, a = unique article id) article number, a = unique article id)
412 no news group selected 412 no news group selected
420 no current article has been selected 420 no current article has been selected
422 no previous article in this group 422 no previous article in this group
10.1.1.3 NEXT 10.1.1.3 NEXT
skipping to change at line 811 skipping to change at page 16, line 25
421 no next article in this group 421 no next article in this group
10.2 Retrieval of Articles and Article Sections 10.2 Retrieval of Articles and Article Sections
There are two forms to the ARTICLE command (and the related There are two forms to the ARTICLE command (and the related
BODY, HEAD, and STAT commands), each using a different method BODY, HEAD, and STAT commands), each using a different method
of specifying which article is to be retrieved. When the of specifying which article is to be retrieved. When the
ARTICLE keyword is followed by a message-id in angle brackets ARTICLE keyword is followed by a message-id in angle brackets
("<" and ">"), the first form of the command MUST be used; ("<" and ">"), the first form of the command MUST be used;
when a numeric parameter or no parameter is supplied, the when a numeric parameter or no parameter is supplied, the
second form MUST be invoked. second form MUST be invoked. In the cases where the argument
is a message-id, the article number specified in the response
must be zero. This is one of the special cases described in
section 10.1.
An article, as defined by RFC 1036, consists of two parts: the An article, as defined by RFC 1036, consists of two parts: the
article headers and the article body. When responding to an article headers and the article body. When responding to an
article command, the server returns the entire article article command, the server returns the entire article
contents and does not attempt to alter or translate them in contents and does not attempt to alter or translate them in
any way. any way.
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The HEAD and BODY commands are identical to the ARTICLE
command except that they respectively return only the article
headers or the article body of the article.
The STAT command is similar to the ARTICLE command except that
no text is returned. When selecting by message number within
a group, the STAT command MUST set the current article pointer
without sending text. The returned acknowledgment response
MUST contain the message-id, which may be of some value.
Using the STAT command to select by message-id is valid but of
questionable value, since a selection by message-id MUST NOT
alter the "current article pointer".
10.2.1 ARTICLE 10.2.1 ARTICLE
ARTICLE [<message-id>|nnn] ARTICLE [<message-id>|nnn]
This response displays the header, a blank line, then the body This response displays the header, a blank line, then the body
(text) of the specified article. The optional parameter nnn is (text) of the specified article. The optional parameter nnn is
the numeric id of an article in the current news group and the numeric id of an article in the current news group and
MUST be chosen from the range of articles provided when the SHOULD be chosen from the range of articles provided when the
news group was selected. If it is omitted, the current news group was selected. If it is omitted, the current
article is assumed. Message-id is the message id of an article article is assumed. Message-id is the message id of an article
as shown in that article's header. as shown in that article's header.
Please note that the internally-maintained "current article Please note that the internally-maintained "current article
pointer" MUST NOT be altered when the message-id argument is pointer" MUST NOT be altered when the message-id argument is
used. This is both to facilitate the presentation of articles used. This is both to facilitate the presentation of articles
that may be referenced within an article being read, and that may be referenced within an article being read, and
because of the semantic difficulties of determining the proper because of the semantic difficulties of determining the proper
sequence and membership of an article which may have been sequence and membership of an article which may have been
skipping to change at line 864 skipping to change at page 17, line 16
set when a valid article number is specified as the argument. set when a valid article number is specified as the argument.
This includes the case when an article number is implied by This includes the case when an article number is implied by
the use of no argument. the use of no argument.
A previously valid article number MAY not remain valid if the A previously valid article number MAY not remain valid if the
article has been removed. A previously invalid article number article has been removed. A previously invalid article number
MAY become valid if the article has been reinstated, but such MAY become valid if the article has been reinstated, but such
an article number MUST be no less than the reported low water an article number MUST be no less than the reported low water
mark for that group. mark for that group.
A response indicating the current article number, a message-id If there is a valid article to present in a reply to this
command, a response indicating the current article number (or
zero when the message-id argument is used), a message-id
string, and that text is to follow MUST be returned. string, and that text is to follow MUST be returned.
The message-id string returned is an identification string The message-id string returned is an identification string
contained within angle brackets ("<" and ">"), which is contained within angle brackets ("<" and ">"), which is
derived from the header of the article itself. The Message-ID derived from the header of the article itself. The Message-ID
header line (required by RFC 1036) from the article must be header line (required by RFC 1036) from the article must be
used to supply this information. If the message-id header line used to supply this information. If the message-id header line
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is missing from the article, a single digit "0" (zero) should is missing from the article, a single digit "0" (zero) should
be supplied within the angle brackets. be supplied within the angle brackets.
Since the message-id field is unique for each article, it may Since the message-id field is unique for each article, it may
be used by a news reading program to skip duplicate displays be used by a news reading program to skip duplicate displays
of articles that have been posted more than once, or to more of articles that have been posted more than once, or to more
than one news group. than one news group.
10.2.1.1 Responses 10.2.1.1 Responses
220 n <a> article retrieved - head and body follow (n = 220 n <a> article retrieved - head and body follow (n =
article number, <a> = message-id) article number, <a> = message-id)
412 no news group has been selected
420 no current article has been selected
423 no such article number in this group
430 no such article found
10.2.2 HEAD
HEAD [<message-id>|nnn]
This response displays the header of the specified article.
The optional parameter nnn is the numeric id of an article in
the current news group and SHOULD be chosen from the range of
articles provided when the news group was selected. If it is
omitted, the current article is assumed. Message-id is the
message id of an article as shown in that article's header.
Please note that the internally-maintained "current article
pointer" MUST NOT be altered when the message-id argument is
used. This is both to facilitate the presentation of articles
that may be referenced within an article being read, and
because of the semantic difficulties of determining the proper
sequence and membership of an article which may have been
posted to more than one news group.
The internally-maintained "current article pointer" MUST be
set when a valid article number is specified as the argument.
This includes the case when an article number is implied by
the use of no argument.
A previously valid article number MAY not remain valid if the
article has been removed. A previously invalid article number
MAY become valid if the article has been reinstated, but such
an article number MUST be no less than the reported low water
mark for that group.
If there is a valid article to present in a reply to this
command, a response indicating the current article number (or
zero when the message-id argument is used), a message-id
string, and that text is to follow MUST be returned.
The message-id string returned is an identification string
contained within angle brackets ("<" and ">"), which is
derived from the header of the article itself. The Message-ID
header line (required by RFC 1036) from the article must be
used to supply this information. If the message-id header line
is missing from the article, a single digit "0" (zero) should
be supplied within the angle brackets.
Since the message-id field is unique for each article, it may
be used by a news reading program to skip duplicate displays
of articles that have been posted more than once, or to more
than one news group.
10.2.2.1 Responses
221 n <a> article retrieved - head follows 221 n <a> article retrieved - head follows
412 no news group has been selected
420 no current article has been selected
423 no such article number in this group
430 no such article found
10.2.3 BODY
BODY [<message-id>|nnn]
This response displays the body (text) of the specified
article. The optional parameter nnn is the numeric id of an
article in the current news group and SHOULD be chosen from
the range of articles provided when the news group was
selected. If it is omitted, the current article is assumed.
Message-id is the message id of an article as shown in that
article's header.
Please note that the internally-maintained "current article
pointer" MUST NOT be altered when the message-id argument is
used. This is both to facilitate the presentation of articles
that may be referenced within an article being read, and
because of the semantic difficulties of determining the proper
sequence and membership of an article which may have been
posted to more than one news group.
The internally-maintained "current article pointer" MUST be
set when a valid article number is specified as the argument.
This includes the case when an article number is implied by
the use of no argument.
A previously valid article number MAY not remain valid if the
article has been removed. A previously invalid article number
MAY become valid if the article has been reinstated, but such
an article number MUST be no less than the reported low water
mark for that group.
If there is a valid article to present in a reply to this
command, a response indicating the current article number (or
zero when the message-id argument is used), a message-id
string, and that text is to follow MUST be returned.
The message-id string returned is an identification string
contained within angle brackets ("<" and ">"), which is
derived from the header of the article itself. The Message-ID
header line (required by RFC 1036) from the article must be
used to supply this information. If the message-id header line
is missing from the article, a single digit "0" (zero) should
be supplied within the angle brackets.
Since the message-id field is unique for each article, it may
be used by a news reading program to skip duplicate displays
of articles that have been posted more than once, or to more
than one news group.
10.2.3.1 Responses
222 n <a> article retrieved - body follows 222 n <a> article retrieved - body follows
412 no news group has been selected
420 no current article has been selected
423 no such article number in this group
430 no such article found
10.2.4 STAT
STAT [<message-id>|nnn]
This response returns only status information; no article
contents are returned. The optional parameter nnn is the
numeric id of an article in the current news group and SHOULD
be chosen from the range of articles provided when the news
group was selected. If it is omitted, the current article is
assumed. Message-id is the message id of an article as shown
in that article's header.
Please note that the internally-maintained "current article
pointer" MUST NOT be altered when the message-id argument is
used. This is both to facilitate the presentation of articles
that may be referenced within an article being read, and
because of the semantic difficulties of determining the proper
sequence and membership of an article which may have been
posted to more than one news group.
The internally-maintained "current article pointer" MUST be
set when a valid article number is specified as the argument.
This includes the case when an article number is implied by
the use of no argument.
A previously valid article number MAY not remain valid if the
article has been removed. A previously invalid article number
MAY become valid if the article has been reinstated, but such
an article number MUST be no less than the reported low water
mark for that group.
If there is a valid article to present in a reply to this
command, a response indicating the current article number (or
zero when the message-id argument is used) and a message-id
string MUST be returned.
The message-id string returned is an identification string
contained within angle brackets ("<" and ">"), which is
derived from the header of the article itself. The Message-ID
header line (required by RFC 1036) from the article must be
used to supply this information. If the message-id header line
is missing from the article, a single digit "0" (zero) should
be supplied within the angle brackets.
Since the message-id field is unique for each article, it may
be used by a news reading program to skip duplicate displays
of articles that have been posted more than once, or to more
than one news group.
10.2.4.1 Responses
223 n <a> article retrieved - request text separately 223 n <a> article retrieved - request text separately
412 no news group has been selected 412 no news group has been selected
420 no current article has been selected 420 no current article has been selected
423 no such article number in this group 423 no such article number in this group
430 no such article found 430 no such article found
10.3 Article Posting 10.3 Article Posting
Article posting is done in one of two modes: individual Article posting is done in one of two modes: individual
article posting from news reading clients and article transfer article posting from news reading clients and article transfer
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10.3.1 POST 10.3.1 POST
POST POST
If posting is allowed, response code 340 MUST be returned to If posting is allowed, response code 340 MUST be returned to
indicate that the article to be posted should be sent. indicate that the article to be posted should be sent.
Response code 440 MUST be sent if that posting is prohibited Response code 440 MUST be sent if that posting is prohibited
for some installation-dependent reason. for some installation-dependent reason.
If posting is permitted, the article MUST be presented in the If posting is permitted, the article MUST be presented to the
format specified by RFC 1036, and MUST include all required server by the client in the format specified by RFC 1036. The
header lines. After the article's header and body have been text forming the header and body of the message to be posted
completely sent by the client to the server, a further MUST be sent by the client using the conventions for text
response code MUST be returned to indicate success or failure received from the news server: A single period (".") on a line
of the posting attempt. indicates the end of the text, with lines starting with a
The text forming the header and body of the message to be
posted MUST be sent by the client using the conventions for
text received from the news server: A single period (".") on a
line indicates the end of the text, with lines starting with a
period in the original text having that period doubled during period in the original text having that period doubled during
transmission. transmission.
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client, the server MUST return a response code indicating
success or failure of the article transfer.
No attempt shall be made by the server to filter characters, No attempt shall be made by the server to filter characters,
fold or limit lines, or otherwise process incoming text. The fold or limit lines, or otherwise process incoming text. The
intent is that the server just passes the incoming message to intent is that the server just passes the incoming message to
be posted to the server installation's news posting software, be posted to the server installation's news posting software,
which is not part of this specification. which is not part of this specification.
10.3.1.1 Responses 10.3.1.1 Responses
240 article posted ok 240 article received ok
340 send article to be posted. End with <CR-LF>.<CR-LF> 340 send article to be posted. End with <CR-LF>.<CR-LF>
440 posting not allowed 440 posting not allowed
441 posting failed 441 posting failed
10.3.2 IHAVE 10.3.2 IHAVE
IHAVE <message-id> IHAVE <message-id>
The IHAVE command informs the server that the client has an The IHAVE command informs the server that the client has an
article whose id is <message-id>. If the server desires a copy article whose id is <message-id>. If the server desires a copy
skipping to change at line 965 skipping to change at page 22, line 15
This function differs from the POST command in that it is This function differs from the POST command in that it is
intended for use in transferring already-posted articles intended for use in transferring already-posted articles
between hosts. Normally it will not be used when the client is between hosts. Normally it will not be used when the client is
a personal news reading program. In particular, this function a personal news reading program. In particular, this function
will invoke the server's news posting program with the will invoke the server's news posting program with the
appropriate settings (flags, options, etc.) to indicate that appropriate settings (flags, options, etc.) to indicate that
the forthcoming article is being forwarded from another host. the forthcoming article is being forwarded from another host.
However, the server may elect not to post or forward the However, the server may elect not to post or forward the
article if after further examination of the article it deems article if after further examination of the article it deems
it inappropriate to do so. The 436 or 437 error codes MUST be it inappropriate to do so. Reasons for such subsequent
returned as appropriate to the situation. rejection of an article may include such problems as
inappropriate news groups or distributions, disk space
Reasons for such subsequent rejection of an article may limitations, article lengths, garbled headers, and the like.
include such problems as inappropriate news groups or These are typically restrictions enforced by the server host's
distributions, disk space limitations, article lengths, news software and not necessarily the NNTP server itself.
garbled headers, and the like. These are typically
restrictions enforced by the server host's news software and
not necessarily the NNTP server itself.
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10.3.2.1 Responses 10.3.2.1 Responses
235 article transferred ok 235 article transferred ok
335 send article to be transferred. End with <CR- 335 send article to be transferred. End with <CR-
LF>.<CR-LF> LF>.<CR-LF>
435 article not wanted - do not send it 435 article not wanted - do not send it
436 transfer failed - try again later 436 transfer failed - try again later
437 article rejected - do not try again 437 article rejected - do not try again
Because some host news posting software may not be able to Because some host news posting software may not be able to
skipping to change at line 1025 skipping to change at page 23, line 20
The <first> and <last> fields will always be numeric. They The <first> and <last> fields will always be numeric. They
may have leading zeros. If the <last> field evaluates to less may have leading zeros. If the <last> field evaluates to less
than the <first> field, there are no articles currently on than the <first> field, there are no articles currently on
file in the news group. file in the news group.
Note that posting may still be prohibited to a client although Note that posting may still be prohibited to a client although
the LIST command indicates that posting is permitted to a the LIST command indicates that posting is permitted to a
particular news group. See the POST command for an explanation particular news group. See the POST command for an explanation
of client prohibitions. The posting flag exists for each news of client prohibitions. The posting flag exists for each news
group because some news groups are moderated or are digests, group because some news groups are moderated or are digests,
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and therefore cannot be posted to; that is, articles posted to and therefore cannot be posted to; that is, articles posted to
them must be mailed to a moderator who will post them for the them must be mailed to a moderator who will post them for the
original poster. This is independent of the posting original poster. This is independent of the posting
permission granted to a client by the NNTP server. permission granted to a client by the NNTP server.
Please note that an empty list (i.e., the text body returned Please note that an empty list (i.e., the text body returned
by this command consists only of the terminating period) is a by this command consists only of the terminating period) is a
possible valid response, and indicates that there are possible valid response, and indicates that there are
currently no valid news groups. currently no valid news groups.
skipping to change at line 1078 skipping to change at page 24, line 19
server, and multiple groups may be specified by using wildmat server, and multiple groups may be specified by using wildmat
patterns (described in section 5), not regular expression patterns (described in section 5), not regular expression
10.4.2.1 Responses 10.4.2.1 Responses
215 information follows 215 information follows
503 program error, function not performed 503 program error, function not performed
10.4.3 LIST DISTRIBUTIONS 10.4.3 LIST DISTRIBUTIONS
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LIST DISTRIBUTIONS LIST DISTRIBUTIONS
The distributions file is maintained by some news transport The distributions file is maintained by some news transport
systems to contain information about valid values for the systems to contain information about valid values for the
Distribution: line in a news article header and about what the Distribution: line in a news article header and about what the
values mean. Each line contains two fields, the value and a values mean. Each line contains two fields, the value and a
short explanation on the meaning of the value. When executed, short explanation on the meaning of the value. When executed,
the information is displayed following the 215 response. When the information is displayed following the 215 response. When
display is completed, the server will send a period on a line display is completed, the server will send a period on a line
by itself. If the information is not available, the server by itself. If the information is not available, the server
skipping to change at line 1128 skipping to change at page 25, line 17
10.4.4.1 Responses 10.4.4.1 Responses
215 information follows 215 information follows
503 program error, function not performed 503 program error, function not performed
10.4.5 LIST NEWSGROUPS 10.4.5 LIST NEWSGROUPS
LIST NEWSGROUPS [wildmat] LIST NEWSGROUPS [wildmat]
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The newsgroups file is maintained by some news transport The newsgroups file is maintained by some news transport
systems to contain the name of each news group that is systems to contain the name of each news group that is
active on the server and a short description about the active on the server and a short description about the
purpose of each news group. Each line in the file contains purpose of each news group. Each line in the file contains
two fields, the news group name and a short explanation of two fields, the news group name and a short explanation of
the purpose of that news group. When executed, the the purpose of that news group. When executed, the
information is displayed following the 215 response. When information is displayed following the 215 response. When
display is completed, the server will send a period on a display is completed, the server will send a period on a
line by itself. If the information is not available, the line by itself. If the information is not available, the
server will return the 503 response. If the optional server will return the 503 response. If the optional
skipping to change at line 1161 skipping to change at page 25, line 49
10.4.6 LIST OVERVIEW.FMT 10.4.6 LIST OVERVIEW.FMT
LIST OVERVIEW.FMT LIST OVERVIEW.FMT
The overview.fmt file is maintained by some news transport The overview.fmt file is maintained by some news transport
systems to contain the order in which header information is systems to contain the order in which header information is
stored in the overview databases for each news group. When stored in the overview databases for each news group. When
executed, news article header fields are displayed one line at executed, news article header fields are displayed one line at
a time in the order in which they are stored in the overview a time in the order in which they are stored in the overview
database[6] following the 215 response. When display is database[8] following the 215 response. When display is
completed, the server will send a period on a line by itself. completed, the server will send a period on a line by itself.
If the information is not available, the server will return If the information is not available, the server will return
the 503 response. the 503 response.
Please note that if the header has the word "full" (without Please note that if the header has the word "full" (without
quotes) after the colon, the header's name is prepended to its quotes) after the colon, the header's name is prepended to its
field in the output returned by the server. field in the output returned by the server.
10.4.6.1 Responses 10.4.6.1 Responses
215 information follows 215 information follows
503 program error, function not performed 503 program error, function not performed
10.4.7 LIST SUBSCRIPTIONS 10.4.7 LIST SUBSCRIPTIONS
LIST SUBSCRIPTIONS LIST SUBSCRIPTIONS
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This command is used to get a default subscription list for This command is used to get a default subscription list for
new users of this server. The order of groups is significant. new users of this server. The order of groups is significant.
When this list is available, it is preceded by the 215 When this list is available, it is preceded by the 215
response and followed by a period on a line by itself. When response and followed by a period on a line by itself. When
this list is not available, the server returns a 503 response this list is not available, the server returns a 503 response
code. code.
10.4.7.1 Responses 10.4.7.1 Responses
skipping to change at line 1218 skipping to change at page 27, line 5
by itself. by itself.
When a valid group is selected by means of this command, the When a valid group is selected by means of this command, the
internally maintained "current article pointer" MUST be set internally maintained "current article pointer" MUST be set
to the first article in the group. If an invalid group is to the first article in the group. If an invalid group is
specified, the previously selected group and article remain specified, the previously selected group and article remain
selected. If an empty news group is selected, the "current selected. If an empty news group is selected, the "current
article pointer" may be in an indeterminate state and should article pointer" may be in an indeterminate state and should
not be used. not be used.
Note that the name of the news group is not case-dependent. The group name MUST match a news group obtained from the
It must otherwise match a news group obtained from the LIST LIST command or an error will result, else the server will
command or an error will result. response with the 411 error code.
10.4.8.1 Responses 10.4.8.1 Responses
211 list of article numbers follow 211 list of article numbers follow
411 No such group
412 Not currently in news group 412 Not currently in news group
10.4.9 OVER 10.4.9 OVER
OVER [range] OVER [range]
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The OVER command returns information from the overview The OVER command returns information from the overview
database for the article(s) specified. The information database for the article(s) specified. The information
returned in the response to this command can be used by returned in the response to this command can be used by
clients to follow discussion threads. clients to follow discussion threads.
The optional range argument may be any of the following: The optional range argument may be any of the following:
. an article number . an article number
. an article number followed by a dash to indicate all following . an article number followed by a dash to indicate all following
. an article number followed by a dash followed by another . an article number followed by a dash followed by another
skipping to change at line 1258 skipping to change at page 27, line 45
for the current article is returned. A news group must have for the current article is returned. A news group must have
been selected earlier, else a 412 error response is returned. been selected earlier, else a 412 error response is returned.
If no articles are in the range specified, a 420 error If no articles are in the range specified, a 420 error
response is returned by the server. A 502 response will be response is returned by the server. A 502 response will be
returned if the client only has permission to transfer returned if the client only has permission to transfer
articles. articles.
Each line of output MUST be formatted with the article number, Each line of output MUST be formatted with the article number,
followed by each of the headers in the overview database or followed by each of the headers in the overview database or
the article itself (when the data is not available in the the article itself (when the data is not available in the
overview database) for that article separated by a tab overview database) for that article separated by a US-ASCII
character. The sequence of fields must be in this order: tab character. The sequence of fields must be in this order:
subject, author, date, message-id, references, byte count, and subject, author, date, message-id, references, byte count, and
line count. Other optional fields may follow line count. Where line count. Other optional fields may follow line count. These
no data exists, a null field must be provided (i.e. the output fields are specified by examining the response to the LIST
will have two tab characters adjacent to each other). Servers OVERVIEW.FMT command. Where no data exists, a null field must
should not output fields for articles that have been removed be provided (i.e. the output will have two tab characters
since the overview database was created. adjacent to each other). Servers should not output fields for
articles that have been removed since the overview database
was created.
Note that all US-ASCII tab characters in any header data that
is returned will be converted to a single US-ASCII space
character.
10.4.9.1 Responses 10.4.9.1 Responses
224 Overview information follows 224 Overview information follows
412 No news group current selected 412 No news group current selected
420 No article(s) selected 420 No article(s) selected
502 no permission 502 no permission
10.4.10 PAT 10.4.10 PAT
PAT header range|<message-id> [pat [pat...]] PAT header range|<message-id> [pat [pat...]]
The PAT command is used to retrieve specific headers from The PAT command is used to retrieve specific headers from
specific articles, based on pattern matching on the contents specific articles, based on pattern matching on the contents
of the header. of the header.
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The required header parameter is the name of a header line The required header parameter is the name of a header line
(e.g. "subject") in a news group article. See RFC-1036 for a (e.g. "subject") in a news group article. See RFC-1036 for a
list of valid header lines. The required range argument may be list of valid header lines. The required range argument may be
any of the following: any of the following:
. an article number . an article number
. an article number followed by a dash to indicate all following . an article number followed by a dash to indicate all following
. an article number followed by a dash followed by another . an article number followed by a dash followed by another
article number. article number.
The required message-id argument indicates a specific article. The required message-id argument indicates a specific article.
The range and message-id arguments are mutually exclusive. If The range and message-id arguments are mutually exclusive. If
there are additional arguments, they are joined together there are additional arguments, they are joined together
separated by a single space to form one complete pattern. If separated by a single space to form one complete pattern. If
there are no additional arguments, a wildmat "*" is the there are no additional arguments, a wildmat "*" is the
default. Successful responses start with a 221 response default. Successful responses start with a 221 response
followed by the headers from all messages in which the pattern followed by article number, a US-ASCII space, and the header
matched the contents of the specified header line. This from that message in which the pattern matched the contents of
includes an empty list. Once the output is complete, a period the specified header line. A valid response includes an empty
is sent on a line by itself. If the optional argument is a list (indicating that there was no matches). Once the output
message-id and no such article exists, the 430 error response is complete, a period is sent on a line by itself. If the
shall be returned. A 502 response shall be returned if the optional argument is a message-id and no such article exists,
client only has permission to transfer articles. the 430 error response shall be returned. A 502 response shall
be returned if the client only has permission to transfer
articles.
10.4.10.1 Responses 10.4.10.1 Responses
221 Header follows 221 Header follows
430 no such article 430 no such article
502 no permission 502 no permission
11. The CONCLUSION Step 11. The CONCLUSION Step
11.1 QUIT 11.1 QUIT
QUIT QUIT
The server process MUST acknowledge the QUIT command and then The server process MUST acknowledge the QUIT command and then
closes the connection to the client. This is the preferred closes the connection to the client. This is the preferred
method for a client to indicate that it has finished all its method for a client to indicate that it has finished all its
transactions with the NNTP server. transactions with the NNTP server.
skipping to change at line 1333 skipping to change at page 29, line 25
If a client simply disconnects (or the connection times out or If a client simply disconnects (or the connection times out or
some other fault occurs), the server SHALL gracefully cease some other fault occurs), the server SHALL gracefully cease
its attempts to service the client. its attempts to service the client.
11.1.1 Responses 11.1.1 Responses
205 closing connection - goodbye! 205 closing connection - goodbye!
12. Other Keywords 12. Other Keywords
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There are other Keywords that may be used at any time between There are other Keywords that may be used at any time between
the beginning of a session and its termination. Using these the beginning of a session and its termination. Using these
keywords do not alter any state information, but the response keywords do not alter any state information, but the response
generated from the use of these keywords may provide useful generated from the use of these keywords may provide useful
information to clients that use them. information to clients that use them.
12.1 CHARSET 12.1 DATE
CHARSET [charset]
The CHARSET command is used to change the default character
set for certain types of arguments: group names and the
contents of article headers. The argument must be the name of
a character set registered with the IANA. The server MUST
return 204 if the specified character set is supported.
Otherwise, the server MUST return 404.
When used as arguments to commands, group names and the
contents of article headers MUST be decoded before comparing
text in a character set other than US-ASCII. US-ASCII must be
supported; other character sets may be supported.
The use of CHARSET with no argument will reset the default
character set to US-ASCII.
Note that only argument processing is affected by the
character set. The server MUST not translate any part of any
multi-line response returned to the client based on the
current character set.
12.1.1 Responses
204 Character set is now charset
404 Character set charset is not supported by this
server
500 Command not supported
12.2 DATE
DATE DATE
This command exists to help clients find out the current time This command exists to help clients find out the current time
from the server's perspective. This command should not be from the server's perspective. This command should not be
used as a substitute for NTP[7], but to provide information used as a substitute for NTP[9], but to provide information
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that might be useful when using the NEWNEWS command (see that might be useful when using the NEWNEWS command (see
section 12.5). section 12.4).
This command returns a one-line response code of 111 followed This command returns a one-line response code of 111 followed
by the GMT date and time on the server in the form by the UTC (or GMT) date and time on the server in the form
YYYYMMDDhhmmss. YYYYMMDDhhmmss.
12.2.1 Responses 12.1.1 Responses
111 YYYYMMDDhhmmss 111 YYYYMMDDhhmmss
12.3 The HELP Command 12.2 The HELP Command
HELP HELP
This command provides a short summary of commands that are This command provides a short summary of commands that are
understood by this implementation of the server. The help text understood by this implementation of the server. The help text
will be presented as a textual response terminated by a single will be presented as a textual response terminated by a single
period on a line by itself. period on a line by itself.
This text is not guaranteed to be in any particular format and This text is not guaranteed to be in any particular format and
shall not be used by clients as a replacement for the LIST shall not be used by clients as a replacement for the LIST
EXTENSIONS command described in section 8. EXTENSIONS command described in section 8.1.
12.3.1 Responses 12.2.1 Responses
100 help text follows 100 help text follows
12.4 NEWGROUPS 12.3 NEWGROUPS
NEWGROUPS date time [GMT] [<wildmat>] NEWGROUPS date time [GMT|UTC] [<distributions>]
A list of newsgroups created since <date and time> MUST be A list of newsgroups created since <date and time> MUST be
listed in the same format as the LIST command. listed in the same format as the LIST command.
The date is sent as 6 or 8 digits in the format [XX]YYMMDD, The date is sent as 6 or 8 digits in the format [XX]YYMMDD,
where XX is the first two digits of the year, YY is the last two where XX is the first two digits of the year, YY is the last
digits of the year, MM is the two digits of the month (with two digits of the year, MM is the two digits of the month
leading zero, if appropriate), and DD is the day of the month (with leading zero, if appropriate), and DD is the day of the
(with leading zero, if appropriate). If the first two digits month (with leading zero, if appropriate). If the first two
of the year are not specified, the closest century is assumed digits of the year are not specified, the year is taken to be
as part of the year (i.e., 86 specifies 1986, 30 specifies in the range 1951 to 2050 inclusive.
2030, 99 is 1999, 00 is 2000).
Time must also be specified. It must be as 6 digits HHMMSS Time must also be specified. It must be as 6 digits HHMMSS
with HH being hours on the 24-hour clock, MM minutes 00-59, with HH being hours in the 24-hour clock 00-23, MM minutes 00-
and SS seconds 00-59. The time is assumed to be in the 59, and SS seconds 00-60, which allows for leap seconds. The
server's timezone unless the token "GMT" appears in which case tokens "GMT" and "UTC" specifies that the date and time are
both time and date are evaluated at the 0 meridian. given in UTC. If the tokens "GMT" and "UTC" are omitted then
the date and time are specified in the server's local
timezone. Note that there is no way within this specification
of NNTP to establish the server's local timezone.
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An optional parameter may be specified at the end of the distribution groups, enclosed in angle brackets. If
command line consisting of a wildmat pattern against which new specified, the distribution portion of an article's header
newsgroup names can be matched enclosed in angle brackets. will be examined for a match with the distribution categories
Only those news groups that have names that match the pattern listed, and only those articles which have a distribution in
(and any other criteria specified in the command) will be the list will be listed. If more than one distribution is to
returned. be supplied, they must be separated by commas within the angle
brackets..
Please note that an empty list (i.e., the text body returned Note that an empty list (i.e., the text body returned by this
by this command consists only of the terminating period) is a command consists only of the terminating period) is a possible
possible valid response, and indicates that there are valid response, and indicates that there are currently no new
currently no new newsgroups. newsgroups.
12.4.1 Responses 12.3.1 Responses
231 list of new newsgroups follows 231 list of new newsgroups follows
12.5 NEWNEWS 12.4 NEWNEWS
NEWNEWS newsgroups date time [GMT] [<distributions>] NEWNEWS newsgroups date time [GMT] [<distributions>]
A list of message-ids of articles posted or received to the A list of message-ids of articles posted or received to the
specified news group since "date" will be listed. The format specified news group since "date" will be listed. The format
of the listing will be one message-id per line, as though text of the listing will be one message-id per line, as though text
were being sent. A single line consisting solely of one were being sent. A single line consisting solely of one
period followed by CR-LF will terminate the list. period followed by CR-LF will terminate the list.
Date and time are in the same format as the NEWGROUPS command. Date and time are in the same format as the NEWGROUPS command.
The newsgroups parameter must be in wildmat format. The newsgroups parameter must be in wildmat format and may
consist of multiple wildmat constructs separated by a US-ASCII
comma character.
The optional parameter "distributions" is a list of The optional parameter "distributions" is a list of
distribution groups, enclosed in angle brackets. If distribution groups, enclosed in angle brackets. If
specified, the distribution portion of an article's header specified, the distribution portion of an article's header
will be examined for a match with the distribution categories will be examined for a match with the distribution categories
listed, and only those articles which have a distribution in listed, and only those articles which have a distribution in
the list will be listed. If more than one distribution is to the list will be listed. If more than one distribution is to
be supplied, they must be separated by commas within the angle be supplied, they must be separated by commas within the angle
brackets. brackets.
The use of the IHAVE, NEWNEWS, and NEWGROUPS commands to The use of the IHAVE, NEWNEWS, and NEWGROUPS commands to
distribute news is discussed in an earlier part of this distribute news is discussed in an earlier part of this
document. document.
Please note that an empty list (i.e., the text body returned Note that an empty list (i.e., the text body returned by this
by this command consists only of the terminating period) is a command consists only of the terminating period) is a possible
possible valid response, and indicates that there is currently valid response, and indicates that there is currently no new
no new news. news.
12.5.1 Responses 12.4.1 Responses
230 list of new articles by message-id follows 230 list of new articles by message-id follows
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13. Framework for NNTP Extensions 13. Framework for NNTP Extensions
Although NNTP is widely and robustly deployed, some parts of Although NNTP is widely and robustly deployed, some parts of
the Internet community might wish to extend the NNTP service. the Internet community might wish to extend the NNTP service.
This memo defines a means whereby an extended NNTP client may This memo defines a means whereby an extended NNTP client may
query the server to determine the service extensions that it query the server to determine the service extensions that it
supports. supports.
It must be emphasized that any extension to the NNTP service It must be emphasized that any extension to the NNTP service
should not be considered lightly. NNTP's strength comes should not be considered lightly. NNTP's strength comes
skipping to change at line 1511 skipping to change at page 32, line 23
many cases, the cost of extending the NNTP service will likely many cases, the cost of extending the NNTP service will likely
outweigh the benefit. outweigh the benefit.
Given this environment, the framework for the extensions Given this environment, the framework for the extensions
described in this memo consists of: described in this memo consists of:
a) a mechanism for clients to determine a server's available a) a mechanism for clients to determine a server's available
extensions extensions
b) a registry of NNTP service extensions b) a registry of NNTP service extensions
The LIST EXTENSIONS command is described in section 8 of this The LIST EXTENSIONS command is described in section 8.1 of
memo and is the mechanism for clients to use to determine what this memo and is the mechanism for clients to use to determine
extensions are available for client use. what extensions are available for client use.
The IANA shall maintain a registry of NNTP service extensions. The IANA shall maintain a registry of NNTP service extensions.
Associated with each such extension is a corresponding NNTP Associated with each such extension is a corresponding NNTP
keyword value. Each service extension registered with the IANA keyword value. Each service extension registered with the IANA
MUST be defined in an RFC. Such RFCs either must be on the MUST be defined in an RFC. Such RFCs either must be on the
standards-track or must define an IESG-approved experimental standards-track or must define an IESG-approved experimental
protocol. The definition must include: protocol. The definition must include:
. the textual name of the NNTP service extension; . the textual name of the NNTP service extension;
. the NNTP keyword value associated with the extension; . the NNTP keyword value associated with the extension;
. the syntax and possible values of parameters associated with . the syntax and possible values of parameters associated with
the NNTP keyword value; the NNTP keyword value;
. any additional NNTP verbs associated with the extension . any additional NNTP verbs associated with the extension
. (additional verbs will usually be, but are not required to be, . (additional verbs will usually be, but are not required to be,
the same as the NNTP keyword value); the same as the NNTP keyword value);
. any new parameters the extension associated with any other . any new parameters the extension associates with any other
NNTP verbs; NNTP verbs;
. how support for the extension affects the behavior of a server . how support for the extension affects the behavior of a server
and client NNTP; and, and client NNTP; and,
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. the increment by which the extension is increasing the maximum . the increment by which the extension is increasing the maximum
length of the any commands over that specified in this length of the any commands over that specified in this
document. document.
In addition, any NNTP keyword value that starts with an upper In addition, any NNTP keyword value that starts with an upper
or lower case "X" refers to a local NNTP service extension, or lower case "X" refers to a local NNTP service extension,
which is used through bilateral, rather than standardized, which is used through bilateral, rather than standardized,
agreement. Keywords beginning with "X" may not be used in a agreement. Keywords beginning with "X" may not be used in a
registered service extension. registered service extension.
Any keyword values presented in the NNTP response that do not Any keyword values presented in the NNTP response that do not
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Identification and AUTHINFO Defined in this Identification and AUTHINFO Defined in this
Authentication AUTHINFO GENERIC document Authentication AUTHINFO GENERIC document
Character Set CHARSET Defined in this Character Set CHARSET Defined in this
Selection document Selection document
Header Pattern PAT Defined in this Header Pattern PAT Defined in this
Matching document Matching document
14. Security Considerations 14. Augmented BNF[10] Syntax for NNTP Commands
This syntax defines the non-terminal "command". The non-terminal
"parameter" is used for command parameters whose syntax is
specified elsewhere. The syntax is in alphabetical order. Note
that ABNF strings are case insensitive.
article-command = "ARTICLE" [1*WSP (msg-id / article-number)]
*WSP CRLF
article-number = 1*16DIGIT
augument = parameter ; excluding sequence ".."
authenticator = parameter ; excluding sequence ".."
authinfo-generic-command = "AUTHINFO" 1*WSP "GENERIC" 1*WSP
authenticator *(1*WSP argument) *WSP CRLF
authinfo-pass-command = "AUTHINFO" 1*WSP "PASS" 1*WSP password
*WSP CRLF
authinfo-user-command = "AUTHINFO" 1*WSP "USER" 1*WSP username
*WSP CRLF
body-command = "BODY" [1*WSP (msg-id / article-number)] *WSP
CRLL
command = article-command /
authinfo-generic-command /
authinfo-pass-command /
authinfo-user-command /
body-command /
date-command /
group-command /
head-command /
help-command /
ihave-command /
last-command /
list-active-times-command /
list-distrib-pats-command /
list-distributions-command /
list-extensions-command /
list-newsgroups-command /
list-overview-fmt-command /
list-subscriptions-command /
list-command /
listgroup-command /
mode-reader-command /
newgroups-command /
newnews-command /
next-command /
over-command /
pat-command /
post-command /
quit-command /
stat-command
CR = %x0D
CRLF = CR LF
date-command = "DATE" *WSP CRLF
date = 6*8DIGIT
DIGIT = %x30-39
distribution = parameter
group-command = "GROUP" 1*WSP newsgroup *WSP CRLF
head-command = "HEAD" [1*WSP (msg-id / article-number)] *WSP
CRLF
header = parameter
help-command = "HELP" *WSP CRLF
HT = %x09
ihave-command = "IHAVE" 1*WSP msg-id *WSP CRLF
last-command = "LAST" *WSP CRLF
LF = %x0A
list-active-times-command = "LIST" 1*WSP "ACTIVE.TIMES"
[1*WSP wildmat] *WSP CRLF
list-command = "LIST" [1*WSP "ACTIVE" [1*WSP wildmat]] *WSP
CRLF
list-distrib-pats-command = "LIST" 1*WSP "DISTRIB.PATS" *WSP
CRLF
list-distributions-command = "LIST" 1*WSP "DISTRIBUTIONS" *WSP
CRLF
list-extensions-command = "LIST" 1*WSP "EXTENSIONS" *WSP CRLF
list-newsgroups-command = "LIST" 1*WSP "NEWSGROUPS" [1*WSP
wildmat]
*WSP CRLF
list-overview-fmt-command = "LIST" 1*WSP "OVERVIEW.FMT" *WSP
CRLF
list-subscriptions-command = "LIST" 1*WSP "SUBSCRIPTIONS" *WSP
CRLF
listgroup-command = "LISTGROUP" [1*WSP newsgroup] *WSP CRLF
mode-reader-command = "MODE" 1*WSP "READER" *WSP CRLF
msg-id = <defined in RFC822>
newgroups-command = "NEWGROUPS" 1*WSP date 1*WSP time [1*WSP
"GMT"/"UTC"][1*WSP "<" distribution *("," distribution)
">"] *WSP CRLF
newnews-command = "NEWNEWS" 1*WSP newsgroup *("," newsgroup)
1*WSP date 1*WSP time [1*WSP "GMT"/"UTC"]
[1*WSP "<" distribution *("," distribution) ">"]
*WSP CRLF
newsgroup = parameter
next-command = "NEXT" *WSP CRLF
over-command = "OVER" [1*WSP range] *WSP CRLF
parameter = 1*(%x21-FF) ; generic command parameter
password = parameter
pat-command = "PAT" 1*WSP header 1*WSP (range / msg-id)
*(1*WSP wildmat) *WSP CRLF
post-command = "POST" *WSP CRLF
quit-command = "QUIT" *WSP CRLF
range = article-number ["-" [article-number]]
SP = %x20
stat-command = "STAT" [1*WSP (msg-id / article-number)] *WSP
CRLF
time = 6DIGIT
username = parameter
wildmat = 1*("*" / "?" / wildmat-exact / wildmat-set / "\"
%x21-FF)
wildmat-exact = %x21-29 / %x2B-3E / %x40-5A / %x5D-FF
; exclude space * ? [ \
wildmat-non-hyphen = %x21-2C / %x2E-FF ; exclude space -
wildmat-set = "[" ["^"] ["]" / "-"]
*(wildmat-non-hyphen ["-" wildmat-non-hyphen])
["-"] "]"
WSP = SP / HT
15. Security Considerations
The use of the AUTHINFO is optional. This command as The use of the AUTHINFO is optional. This command as
documented has a number of security implications. In the documented has a number of security implications. In the
original and simple forms, all passwords are passed in plain original form, all passwords are passed in plain text and
could be discovered by various forms of network or system
surveillance. The AUTHINFO GENERIC command has the potential
for the same problems if a mechanism is used that also passes
clear text passwords. RFC 1731 discusses these issues in
greater detail.
Barber [Page 31] 16. References
text and could be discovered by various forms of network or
system surveillance. The AUTHINFO GENERIC command has the
potential for the same problems if a mechanism is used that
also passes clear text passwords. RFC 1731 discusses these
issues in greater detail.
15. References [1] Kantor, B and P. Lapsley, "Network News Transfer Protocol",
RFC-977, U.C. San Diego and U.C. Berkeley.
[1] Kantor, B and P. Lapsley, "Network News Transfer [2] Yergeau, F., "UTF-8, a transformation format of Unicode and
Protocol", RFC-977, U.C. San Diego and U.C. Berkeley. ISO 10646", RFC 2044, Alis Technologies.
[2] Coded Character Set"7-bit American Standard Code for [3] Coded Character Set-7-bit American Standard Code for
Information Interchange, ANSI x3.4-1986. Information Interchange, ANSI x3.4-1986.
[3] Salz, Rich, Manual Page for wildmat(3) from the INN 1.4 [4] Bradner, Scott, "Key words for use in RFCs to Indicate
Requirement Levels", RFC-2119, Harvard University.
[5] Salz, Rich, Manual Page for wildmat(3) from the INN 1.4
distribution, UUNET Technologies, Revision 1.10, April, 1992. distribution, UUNET Technologies, Revision 1.10, April, 1992.
[4] Horton, M.R. and R. Adams, "Standard for interchange of [6] Horton, M.R. and R. Adams, "Standard for interchange of
USENET messages", RFC-1036, AT&T Bell Laboratories and Center USENET messages", RFC-1036, AT&T Bell Laboratories and Center
for Seismic Studies, December, 1987. for Seismic Studies, December, 1987.
[5] Meyers, J, "IMAP4 Authentication Mechanisms", RFC-1731, [7] Meyers, J, "IMAP4 Authentication Mechanisms", RFC-1731,
Carnegie Mellon, December, 1994. Carnegie Mellon, December, 1994.
[6] Robertson, Rob, "FAQ: Overview database / NOV General [8] Robertson, Rob, "FAQ: Overview database / NOV General
Information", ftp://ftp.uu.net/networking/news/nntp/inn/faq- Information", ftp://ftp.uu.net/networking/news/nntp/inn/faq-
nov.Z, January, 1995. nov.Z, January, 1995.
[7] Mills, David L., "Network Time Protocol (Version 3), [9] Mills, David L., "Network Time Protocol (Version 3),
Specification,Implementation and Analysis", RFC-1305, Specification,Implementation and Analysis", RFC-1305,
University of Delaware, March 1992. University of Delaware, March 1992.
15.1 Notes [10] Crocker, D. and Overell, P., "Augmented BNF for Syntax
Specifications: ABNF", RFC-2234, Internet Mail Consortium and
DEC is a registered trademark of Digital Equipment Demon Internet, Ltd.
Corporation.
UNIX is a registered trademark of the Open Group.
VMS is a registered trademark of Digital Equipment
Corporation.
15.2 Acknowledgments
The author acknowledges the original authors of NNTP as
documented in RFC 977: Brian Kantor and Phil Lapsey.
Barber [Page 32]
The author gratefully acknowledges the work of the NNTP
committee chaired by Eliot Lear. The organization of this
document was influenced by the last available draft from this
working group. A special thanks to Eliot for generously
providing the original machine readable sources for that
document.
The author gratefully acknowledges the work of the Marshall The author gratefully acknowledges the work of the Marshall
Rose & John G. Meyers in RFC 1939 and the work of the DRUMS Rose & John G. Meyers in RFC 1939 and the work of the DRUMS
working group, specifically RFC 1869, which is the basis of working group, specifically RFC 1869, which is the basis of
the NNTP extensions mechanism detailed in this document. the NNTP extensions mechanism detailed in this document.
The author gratefully acknowledges the comments and additional The author gratefully acknowledges the comments and additional
information provided by the following individuals in preparing information provided by the following individuals in preparing
one of the progenitors of this document: one of the progenitors of this document:
skipping to change at line 1680 skipping to change at page 37, line 27
. Geoff Huston -- Original author of ANU NEWS . Geoff Huston -- Original author of ANU NEWS
. Phil Lapsey -- Original author of the UNIX reference . Phil Lapsey -- Original author of the UNIX reference
implementation implementation
. Ian Lea -- Maintainer of the TIN newsreader . Ian Lea -- Maintainer of the TIN newsreader
. Chris Lewis -- First known implementor of the AUTHINFO GENERIC . Chris Lewis -- First known implementor of the AUTHINFO GENERIC
extension extension
. Rich Salz -- Original author of INN . Rich Salz -- Original author of INN
. Henry Spencer -- One of the original authors of CNEWS . Henry Spencer -- One of the original authors of CNEWS
. Kim Storm -- Original author of the NN newsreader . Kim Storm -- Original author of the NN newsreader
15.3 Author's Address 19. Author's Address
Stan Barber Stan Barber
P.O. Box 300481 P.O. Box 300481
Houston, Texas, 77230 Houston, Texas, 77230
Email: <sob@academ.com> Email: <sob@academ.com>
This document expires February 5, 1998. This document expires June 1, 1998.
Barber [Page 33]
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