1NNRPD(8) InterNetNews Documentation NNRPD(8)
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6 nnrpd - NNTP server for reader clients
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9 nnrpd [-DfnoSt] [-4 address] [-6 address] [-b address] [-c configfile]
10 [-i initial] [-I instance] [-p port] [-P prefork] [-r reason] [-s
11 padding]
12
14 nnrpd is an NNTP server for newsreaders. It accepts commands on its
15 standard input and responds on its standard output. It is normally
16 invoked by innd(8) with those descriptors attached to a remote client
17 connection. nnrpd also supports running as a standalone daemon.
18 Unlike innd(8), nnrpd supports all NNTP commands for user-oriented
20 reading and posting. nnrpd uses the readers.conf file to control who
21 is authorized to access the Usenet database.
22 On exit, nnrpd will report usage statistics through syslog(3).
24 nnrpd only reads config files (both readers.conf and inn.conf) when it
26 is spawned. You can therefore never change the behavior of a client
27 that's already connected. If nnrpd is run from innd (the default) or
28 from inetd(8), xinetd(8), or some equivalent, a new nnrpd process is
29 spawned for every connection and therefore any changes to configuration
30 files will be immediately effective for all new connections. If you
31 are instead running nnrpd with the -D option, any configuration changes
32 won't take effect until nnrpd is restarted.
33 The inn.conf setting nnrpdflags can be used to pass any of the options
35 below to instances of nnrpd that are spawned directly from innd. Many
36 options only make sense when -D is used, so these options should not be
37 used with nnrpdflags. See also the discussion of nnrpdflags in
38 inn.conf(5).
39 When nnrpdloadlimit in inn.conf is not 0, it will also reject
41 connections if the load average is greater than that value (typically
42 16). nnrpd can also prevent high-volume posters from abusing your
43 resources. See the discussion of exponential backoff in inn.conf(5).
44 nnrpd injects articles into the local server running innd through a
46 UNIX domain socket, or an INET domain socket if not supported. If
47 another server should be used for injection, you can set it with the
48 nnrpdposthost parameter in inn.conf. In case authentication
49 credentials are requested during the injection, nnrpd will use the
50 passwd.nntp file in pathetc.
51
53 -4 address
54 The -4 parameter instructs nnrpd to bind to the specified IPv4
55 address when started as a standalone daemon using the -D flag.
56 This has to be a valid IPv4 address belonging to an interface of
57 the local host. It can also be 0.0.0.0, saying to bind to all
58 addresses (this is the default).
59 -6 address
61 The -6 parameter instructs nnrpd to bind to the specified IPv6
62 address when started as a standalone daemon using the -D flag.
63 This has to be a valid IPv6 address belonging to an interface of
64 the local host. It can also be "::0", saying to bind to all IPv6
65 addresses.
66 By default, nnrpd in daemon mode listens to both IPv4 and IPv6
68 addresses. With this option, it will listen only to the specified
69 IPv6 addresses. On some systems however, a value of "::0" will
70 cause it to listen to all IPv4 addresses as well.
71 -b address
73 Similar to the -4 flag. -b is kept for backwards compatibility.
74 -c configfile
76 By default, nnrpd reads the readers.conf to determine how to
77 authenticate connections. The -c flag specifies an alternate file
78 for this purpose. If the file name isn't fully qualified, it is
79 taken to be relative to pathetc in inn.conf. (This is useful to
80 have several instances of nnrpd running on different ports or IP
81 addresses with different settings.)
82 -D If specified, this parameter causes nnrpd to operate as a daemon.
84 That is, it detaches itself and runs in the background, forking a
85 process for every connection. By default, nnrpd listens on the
86 NNTP port (119), so either innd(8) has to be started on another
87 port or the -p parameter used. Note that with this parameter,
88 nnrpd continues running until killed. This means that it reads
89 inn.conf once on startup and never again until restarted. nnrpd
90 should therefore be restarted if inn.conf is changed.
91 When started in daemon mode, nnrpd will write its PID into a file
93 in the pathrun directory. The file will be named nnrpd.pid if
94 nnrpd listens on port 119 (default), or nnrpd-%d.pid, where %d is
95 replaced with the port that nnrpd is configured to listen on (-p
96 option is given and its argument is not 119).
97 -f If specified, nnrpd does not detach itself and runs in the
99 foreground when started as a standalone daemon using the -D flag.
100 -i initial
102 Specify an initial command to nnrpd. When used, initial is taken
103 as if it were the first command received by nnrpd. After having
104 responded, nnrpd will close the connection.
105 -I instance
107 If specified, instance is used as an additional static portion
108 within message-IDs generated by nnrpd; typically this option would
109 be used where a cluster of machines exist with the same virtual
110 hostname and must be disambiguated during posts.
111 -n The -n flag turns off resolution of IP addresses to names. If you
113 only use IP-based restrictions in readers.conf and can handle IP
114 addresses in your logs, using this flag may result in some
115 additional speed.
116 -o The -o flag causes all articles to be spooled instead of sending
118 them to innd(8). rnews with the -U flag should be invoked from
119 cron on a regular basis to take care of these articles. This flag
120 is useful if innd(8) is accepting articles and nnrpd is started
121 standalone or using inetd(8).
122 -p port
124 The -p parameter instructs nnrpd to listen on port when started as
125 a standalone daemon using the -D flag.
126 -P prefork
128 The -P parameter instructs nnrpd to prefork prefork children
129 awaiting connections when started as a standalone daemon using the
130 -D flag.
131 -r reason
133 If the -r flag is used, then nnrpd will reject the incoming
134 connection giving reason as the text. This flag is used by innd(8)
135 when it is paused or throttled. reason should be encoded in UTF-8.
136 -s padding
138 As each command is received, nnrpd tries to change its "argv" array
139 so that ps(1) will print out the command being executed. To get a
140 full display, the -s flag may be used with a long string as its
141 argument, which will be overwritten when the program changes its
142 title.
143 -S If specified, nnrpd will start a negotiation for a TLS session as
145 soon as connected. To use this flag, the OpenSSL SSL and crypto
146 libraries must have been found at configure time, or --with-openssl
147 specified at configure time. For more information on running nnrpd
148 with TLS support, see "TLS SUPPORT".
149 -t If the -t flag is used, then all client commands and initial
151 responses will be traced by reporting them in syslog. This flag is
152 set by innd(8) under the control of the ctlinnd(8) "trace" command,
153 and is toggled upon receipt of a SIGHUP; see signal(2).
154
156 If INN is built with --with-openssl or if the OpenSSL SSL and crypto
157 libraries are found at configure time, nnrpd will support news reading
158 over TLS (also known as SSL). For clients that use the STARTTLS
159 command, no special configuration is needed beyond creating a TLS/SSL
160 certificate for the server. You should do this in exactly the same way
161 that you would generate a certificate for a web server.
162 If you're happy with a self-signed certificate (which will generate
164 warnings with some news reader clients), you can create and install one
165 in the default path by running "make cert" after "make install" when
166 installing INN, or by running the following commands:
167 umask 077
169 openssl req -new -x509 -nodes -out <pathetc>/cert.pem \
170 -days 366 -keyout <pathetc>/key.pem
171 chown news:news <pathetc>/cert.pem
172 chmod 640 <pathetc>/cert.pem
173 chown news:news <pathetc>/key.pem
174 chmod 600 <pathetc>/key.pem
175 Replace the paths with something appropriate to your INN installation.
177 This will create a self-signed certificate that will expire in a year.
178 The openssl program will ask you a variety of questions about your
179 organization. Enter the fully qualified domain name of your news
180 service (either the server canonical name or a dedicated alias for the
181 news service) as the name the certificate is for.
182 You then have to set these inn.conf parameters with the right paths:
184 tlscapath: <pathetc>
186 tlscertfile: <pathetc>/cert.pem
187 tlskeyfile: <pathetc>/key.pem
188 If you want to use a complete certificate chain, you can directly put
190 it in tlscertfile (like Apache's SSLCertificateFile directive).
191 Alternately, you can put a single certificate in tlscertfile and use
192 tlscafile for additional certificates needed to complete the chain,
193 like a separate authority root certificate.
194 More concretly, when using Let's Encrypt certificates, Certbot's files
196 can be installed as follows:
197 tlscapath: /etc/letsencrypt/live/news.server.com
199 tlscertfile: /etc/letsencrypt/live/news.server.com/fullchain.pem
200 tlskeyfile: /etc/letsencrypt/live/news.server.com/privkey.pem
201 or:
203 tlscapath: /etc/letsencrypt/live/news.server.com
205 tlscafile: /etc/letsencrypt/live/news.server.com/chain.pem
206 tlscertfile: /etc/letsencrypt/live/news.server.com/cert.pem
207 tlskeyfile: /etc/letsencrypt/live/news.server.com/privkey.pem
208 Make sure that the permission rights are properly set so that the news
210 user or the news group can read these directories and files (typically,
211 he should access /etc/letsencrypt/live/news.server.com and
212 /etc/letsencrypt/archive/news.server.com where the real keys are
213 located, and the private key should not be world-readable).
214 There are two common ways for a news client to negotiate a TLS
216 connection: either via the use of a dedicated port (usually 563) on
217 which TLS is immediately negotiated upon connection, or via the now
218 discouraged way (per RFC 8143) to use the STARTTLS command on the usual
219 NNTP port (119) to dynamically upgrade from unencrypted to TLS-
220 protected traffic during an NNTP session. innd does not, however, know
221 how to listen for connections to that separate port (563). You will
222 therefore need to arrange for nnrpd to listen on that port through some
223 other means. This can be done with the -D flag along with "-p 563" and
224 put into your init scripts:
225 su news -s /bin/sh -c '<pathbin>/nnrpd -D -p 563 -S'
227 but the easiest way is probably to add a line like:
229 nntps stream tcp nowait news <pathbin>/nnrpd nnrpd -S
231 to /etc/inetd.conf or the equivalent on your system and let inetd run
233 nnrpd. (Change the path to nnrpd to match your installation.) You may
234 need to replace "nntps" with 563 if "nntps" isn't defined in
235 /etc/services on your system.
236 Optionally, you may set the tlsciphers, tlsciphers13, tlscompression,
238 tlseccurve, tlspreferserverciphers, and tlsprotocols parameters in
239 inn.conf to fine-tune the behaviour of the TLS/SSL negotiation whenever
240 a new attack on the TLS protocol or some supported cipher suite is
241 discovered.
242
244 nnrpd implements the NNTP commands defined in RFC 3977 (NNTP), RFC 4642
245 updated by RFC 8143 (TLS/NNTP), RFC 4643 (NNTP authentication),
246 RFC 6048 (NNTP LIST additions) and RFC 8054 (NNTP compression) with the
247 following differences:
248 1. The XGTITLE [wildmat] command is provided. This extension is used
250 by ANU-News and documented in RFC 2980. It returns a 282 reply
251 code, followed by a one-line description of all newsgroups that
252 match the pattern. The default is the current group.
253 Note that LIST NEWSGROUPS should be used instead of XGTITLE.
255 2. The XHDR header [message-ID|range] command is implemented. It
257 returns a 221 reply code, followed by specific headers for the
258 specified range; the default is to return the data for the current
259 article. See RFC 2980.
260 Note that HDR should be used instead of XHDR.
262 3. The XOVER [range] command is provided. It returns a 224 reply
264 code, followed by the overview data for the specified range; the
265 default is to return the data for the current article. See
266 RFC 2980.
267 Note that OVER should be used instead of XOVER.
269 4. A new command, XPAT header message-ID|range pattern [pattern ...],
271 is provided. The first argument is the case-insensitive name of
272 the header field to be searched. The second argument is either an
273 article range or a single message-ID, as specified in RFC 2980.
274 The third argument is a uwildmat-style pattern; if there are
275 additional arguments, they are joined together separated by a
276 single space to form the complete pattern. This command is similar
277 to the XHDR command. It returns a 221 response code, followed by
278 the text response of all article numbers that match the pattern.
279 5. A newsgroup name is case-sensitive for nnrpd.
281 6. If IHAVE has been advertised, it will not necessarily be advertised
283 for the entire session (contrary to section 3.4.1 of RFC 3977).
284 nnrpd only advertises the IHAVE capability when it is really
285 available.
286 7. nnrpd allows a wider syntax for wildmats and ranges (especially "-"
288 and "-article-number").
289
291 Written by Rich $alz <rsalz@uunet.uu.net> for InterNetNews. Overview
292 support added by Rob Robertston <rob@violet.berkeley.edu> and Rich in
293 January, 1993. Exponential backoff (for posting) added by Dave Hayes
294 in Febuary 1998.
295
297 ctlinnd(8), innd(8), inn.conf(5), libinn_uwildmat(3), nnrpd.track(5),
298 passwd.nntp(5), readers.conf(5), signal(2).
299INN 2.6.5 2022-02-18 NNRPD(8)