Mercurial > notdcc
comparison dccifd.html.in @ 0:c7f6b056b673
First import of vendor version
| author | Peter Gervai <grin@grin.hu> |
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| date | Tue, 10 Mar 2009 13:49:58 +0100 |
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| 1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"> | |
| 2 <HTML> | |
| 3 <HEAD> | |
| 4 <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> | |
| 5 <TITLE>dccifd.0.8</TITLE> | |
| 6 <META http-equiv="Content-Style-Type" content="text/css"> | |
| 7 <STYLE type="text/css"> | |
| 8 BODY {background-color:white; color:black} | |
| 9 ADDRESS {font-size:smaller} | |
| 10 IMG.logo {width:6em; vertical-align:middle} | |
| 11 </STYLE> | |
| 12 </HEAD> | |
| 13 <BODY> | |
| 14 <PRE> | |
| 15 <!-- Manpage converted by man2html 3.0.1 --> | |
| 16 <B><A HREF="dccifd.html">dccifd(8)</A></B> Distributed Checksum Clearinghouse <B><A HREF="dccifd.html">dccifd(8)</A></B> | |
| 17 | |
| 18 | |
| 19 </PRE> | |
| 20 <H2><A NAME="NAME">NAME</A></H2><PRE> | |
| 21 <B>dccifd</B> -- Distributed Checksum Clearinghouse Interface Daemon | |
| 22 | |
| 23 | |
| 24 </PRE> | |
| 25 <H2><A NAME="SYNOPSIS">SYNOPSIS</A></H2><PRE> | |
| 26 <B>dccifd</B> [<B>-VdbxANQ</B>] [<B>-G</B> <I>on</I> | <I>off</I> | <I>noIP</I> | <I>IPmask/xx</I>] [<B>-h</B> <I>homedir</I>] [<B>-I</B> <I>user</I>] | |
| 27 [<B>-p</B> <I>/sock</I> | <I>host,port,rhost/bits</I>] [<B>-o</B> <I>/sock</I> | <I>host,port</I>] | |
| 28 [<B>-D</B> <I>local-domain</I>] [<B>-m</B> <I>map</I>] [<B>-w</B> <I>whiteclnt</I>] [<B>-U</B> <I>userdirs</I>] | |
| 29 [<B>-a</B> <I>IGNORE</I> | <I>REJECT</I> | <I>DISCARD</I>] [<B>-t</B> <I>type,</I>[<I>log-thold,</I>]<I>rej-thold</I>] | |
| 30 [<B>-g</B> [<I>not-</I>]<I>type</I>] [<B>-S</B> <I>header</I>] [<B>-l</B> <I>logdir</I>] [<B>-R</B> <I>rundir</I>] | |
| 31 [<B>-r</B> <I>rejection-msg</I>] [<B>-T</B> <I>tmpdir</I>] [<B>-j</B> <I>maxjobs</I>] | |
| 32 [<B>-B</B> <I>dnsbl-option</I>] [<B>-L</B> <I>ltype,facility.level</I>] | |
| 33 | |
| 34 | |
| 35 </PRE> | |
| 36 <H2><A NAME="DESCRIPTION">DESCRIPTION</A></H2><PRE> | |
| 37 <B>dccifd</B> is a daemon intended to connect spam filters such as SpamAssasin | |
| 38 and mail transfer agents (MTAs) other than sendmail to DCC servers. The | |
| 39 MTA or filter <B>dccifd</B> which in turn reports related checksums to the near- | |
| 40 est DCC server and adds an <I>X-DCC</I> SMTP header line to the message. The | |
| 41 MTA is told to reject the message if it is unsolicited bulk. | |
| 42 | |
| 43 <B>Dccifd</B> is similar to the DCC sendmail milter interface, <B><A HREF="dccm.html">dccm(8)</A></B> and the | |
| 44 DCC Procmail interface, <B><A HREF="dccproc.html">dccproc(8)</A></B>. <B>Dccifd</B> is more efficient than | |
| 45 <B><A HREF="dccproc.html">dccproc(8)</A></B> but not restricted to use with sendmail like <B><A HREF="dccm.html">dccm(8)</A></B>. All | |
| 46 three send reports of checksums related to mail received by DCC clients | |
| 47 and queries about the total number of reports of particular checksums. | |
| 48 | |
| 49 MTA programs use a simple ASCII protocol a subset of SMTP to send a mail | |
| 50 message including its SMTP envelope to the daemon. <B>Dccifd</B> responds with | |
| 51 an indication of whether the message is unsolicited bulk and an optional | |
| 52 copy of the message with an <I>X-DCC</I> header added. The ASCII protocol is | |
| 53 described below and in the <I>include/dccif.h</I> file in the DCC source. There | |
| 54 is a sample C interface routine in the <I>dcclib/dccif.c</I> file in the DCC | |
| 55 source and the <I>dcclib.a</I> library generated from the source. A <I>Perl</I> ver- | |
| 56 sion of the interface routine is in <I>dccifd/dccif.pl</I>. Test or demonstra- | |
| 57 tion programs in the style of <B><A HREF="dccproc.html">dccproc(8)</A></B> that use those interface rou- | |
| 58 tines are in <I>dccifd/dccif-test</I>. | |
| 59 | |
| 60 A subset of ESMTP can be used instead of the ASCII protocol to connect | |
| 61 <B>dccifd</B> to postfix as a "Before-Queue Content Filter." See the <B>-o</B> flag. | |
| 62 | |
| 63 Since the checksums of messages that are whitelisted locally by the <B>-w</B> | |
| 64 <I>whiteclnt</I> file are not reported to the DCC server, <B>dccifd</B> knows nothing | |
| 65 about the total recipient counts for their checksums and so cannot add | |
| 66 <I>X-DCC</I> header lines to such messages. | |
| 67 | |
| 68 Enable the daemon and put its parameters in the <I>dcc</I><B>_</B><I>conf</I> file and start | |
| 69 the daemon with the <I>start-dccifd</I> script. | |
| 70 | |
| 71 The list of servers that <B>dccifd</B> contacts is in the memory mapped file <I>map</I> | |
| 72 shared by local DCC clients. The file is maintained with <B><A HREF="cdcc.html">cdcc(8)</A></B>. | |
| 73 | |
| 74 <A NAME="OPTIONS"><B>OPTIONS</B></A> | |
| 75 The following options are available: | |
| 76 | |
| 77 <A NAME="OPTION-V"><B>-V</B></A> displays the version of <B>dccifd</B>. | |
| 78 | |
| 79 <A NAME="OPTION-d"><B>-d</B></A> enables debugging output from the DCC client software. Additional | |
| 80 <B>-d</B> options increase the number of messages. A single <B>-d</B> | |
| 81 aborted SMTP transactions including those from some "dictionary | |
| 82 attacks." | |
| 83 | |
| 84 <A NAME="OPTION-b"><B>-b</B></A> causes the daemon to not detach itself from the controlling tty and | |
| 85 put itself into the background. | |
| 86 | |
| 87 <A NAME="OPTION-x"><B>-x</B></A> causes the daemon to try "extra hard" to contact a DCC server. | |
| 88 Since it is usually more important to deliver mail than to report | |
| 89 its checksums, <B>dccifd</B> normally does not delay too long while trying | |
| 90 to contact a DCC server. It will not try again for several seconds | |
| 91 after a failure. With <B>-x</B>, it will always try to contact the DCC | |
| 92 server and it will tell the MTA to answer the DATA command with a | |
| 93 4yz temporary failure. | |
| 94 | |
| 95 <A NAME="OPTION-A"><B>-A</B></A> adds to existing X-DCC headers in the message instead of replacing | |
| 96 existing headers of the brand of the current server. | |
| 97 | |
| 98 <A NAME="OPTION-N"><B>-N</B></A> neither adds, deletes, nor replaces existing X-DCC headers in the | |
| 99 message. Each message is logged, rejected, and otherwise handled | |
| 100 the same. | |
| 101 | |
| 102 <A NAME="OPTION-Q"><B>-Q</B></A> only queries the DCC server about the checksums of messages instead | |
| 103 of reporting and querying. This is useful when <B>dccifd</B> is used to | |
| 104 filter mail that has already been reported to a DCC server by | |
| 105 another DCC client. No single mail message should be reported to a | |
| 106 DCC server more than once per recipient, because each report will | |
| 107 increase the apparent "bulkness" of the message. | |
| 108 | |
| 109 It is better to use <I>MXDCC</I> lines in the global <I>whiteclnt</I> file for | |
| 110 your MX mail servers that use DCC than <B>-Q</B>. | |
| 111 | |
| 112 <A NAME="OPTION-G"><B>-G</B></A> <I>on</I> | <I>off</I> | <I>noIP</I> | <I>IPmask/xx</I> | |
| 113 controls <I>greylisting</I>. At least one working greylist server must be | |
| 114 listed in the <I>map</I> file in the DCC home directory. If more than one | |
| 115 is named, they must "flood" or change checksums and they must use | |
| 116 the same <B>-G</B> parameters. See <B><A HREF="dccd.html">dccd(8)</A></B>. Usually all dccm or dccifd | |
| 117 DCC client processes use the same <B>-G</B> parameters. | |
| 118 | |
| 119 <I>IPmask/xx</I> and <I>noIP</I> remove part or all of the IP address from the | |
| 120 greylist triple. The CIDR block size, <I>xx</I>, must be between 1 and | |
| 121 128. 96 is added to block sizes smaller than 33 to make them appro- | |
| 122 priate for the IPv6 addresses used by the DCC. <I>IPmask/96</I> differs | |
| 123 from <I>noIP</I> for IPv4 addresses, because the former retains the IPv4 to | |
| 124 IPv6 mapping prefix. | |
| 125 | |
| 126 <A NAME="OPTION-h"><B>-h</B></A> <I>homedir</I> | |
| 127 overrides the default DCC home directory, <I>@prefix@</I>. | |
| 128 | |
| 129 <A NAME="OPTION-I"><B>-I</B></A> <I>user</I> | |
| 130 specifies the UID and GID of the process. | |
| 131 | |
| 132 <A NAME="OPTION-p"><B>-p</B></A> <I>/sock/name</I> | <I>host,port,rhost/bits</I> | |
| 133 overrides the default address at which programs contact <B>dccifd</B>. The | |
| 134 default is a UNIX domain socket named dccifd in the DCC home direc- | |
| 135 tory. | |
| 136 | |
| 137 The second form specifies a local host name or IP address, a local | |
| 138 TCP port number, and the host names or IP addresses of computers | |
| 139 that can use <B>dccifd</B>. 127.0.0.1 or <I>localhost</I> are common choices for | |
| 140 <I>host</I>. The string <I>@</I> specifies IN_ADDRANY or all local IP addresses. | |
| 141 127.0.0.0/8 is a common choice for <I>rhost/bits</I>. | |
| 142 | |
| 143 <A NAME="OPTION-o"><B>-o</B></A> <I>/sock</I> | <I>host,port</I> | |
| 144 enables SMTP proxy mode instead of the ASCII protocol and specifies | |
| 145 the output connection when <B>dccifd</B> acts as an SMTP proxy. It is the | |
| 146 address of the SMTP server for which <B>dccifd</B> acts as SMTP client. | |
| 147 When <I>/sock</I> is <I>/dev/null</I>, <B>dccifd</B> acts as if there were downstream | |
| 148 SMTP server that always answers "250 ok". The string <I>@</I> specifies | |
| 149 the same IP address as the incoming TCP connection. | |
| 150 | |
| 151 The input to <B>dccifd</B> in SMTP proxy mode is specified with <B>--p</B>. For | |
| 152 example, <B>-p</B> <I>127.0.0.1,10025,127.0.0.1/32</I> <B>-o</B> <I>127.0.0.1,10026</I> could be | |
| 153 used to connect <B>dccifd</B> with Postfix as described in the documenta- | |
| 154 tion in version 2.2.1 Postfix documentation. | |
| 155 | |
| 156 See below concerning the subset of ESMTP used in this mode. | |
| 157 | |
| 158 <A NAME="OPTION-m"><B>-m</B></A> <I>map</I> | |
| 159 specifies a name or path of the memory mapped parameter file instead | |
| 160 of the default <I>map</I> file in the DCC home directory. It should be | |
| 161 created with the <B><A HREF="cdcc.html">cdcc(8)</A></B> command. | |
| 162 | |
| 163 <A NAME="OPTION-w"><B>-w</B></A> <I>whiteclnt</I> | |
| 164 specifies an optional file containing filtering parameters as well | |
| 165 as SMTP client IP addresses, SMTP envelope values, and header values | |
| 166 of mail that is spam or is not spam and does not need a <I>X-DCC</I> | |
| 167 header, and whose checksums should not be reported to the DCC | |
| 168 server. | |
| 169 | |
| 170 If the pathname <I>whiteclnt</I> is not absolute, it is relative to the DCC | |
| 171 home directory. | |
| 172 | |
| 173 The format of the <B>dccifd</B> whiteclnt file is the same as the <I>whitelist</I> | |
| 174 files used by <B><A HREF="dbclean.html">dbclean(8)</A></B> and the <I>whiteclnt</I> file used by <B><A HREF="dccproc.html">dccproc(8)</A></B>. | |
| 175 See <B><A HREF="dcc.html">dcc(8)</A></B> for a description of DCC white and blacklists. Because | |
| 176 the contents of the <I>whiteclnt</I> file are used frequently, a companion | |
| 177 file is automatically created and maintained. It has the same path- | |
| 178 name but with an added suffix of <I>.dccw</I> and contains a memory mapped | |
| 179 hash table of the main file. | |
| 180 | |
| 181 A whitelist entry ("OK") or two or more semi-whitelistings ("OK2") | |
| 182 for one of the message's checksums prevents all of the message's | |
| 183 checksums from being reported to the DCC server and the addition of | |
| 184 a <I>X-DCC</I> header line by <B>dccifd</B> A whitelist entry for a checksum also | |
| 185 prevents rejecting or discarding the message based on DCC recipient | |
| 186 counts as specified by <B>-a</B> and <B>-t</B>. Otherwise, one or more checksums | |
| 187 with blacklisting entries ("MANY") cause all of the message's check- | |
| 188 sums to be reported to the server with an addressee count of "MANY". | |
| 189 | |
| 190 If the message has a single recipient, an <I>env</I><B>_</B><I>To</I> <I>whiteclnt</I> entry of | |
| 191 "OK" for the checksum of its recipient address acts like any other | |
| 192 <I>whiteclnt</I> entry of "OK." When the SMTP message has more than one | |
| 193 recipient, the effects can be complicated. When a message has sev- | |
| 194 eral recipients with some but not all listed in the <I>whiteclnt</I> file, | |
| 195 <B>dccifd</B> tries comply with the wishes of the users who want filtering | |
| 196 as well as those who don't by silently not delivering the message to | |
| 197 those who want filtering (i.e. are not whitelisted) and delivering | |
| 198 the message to don't want filtering. | |
| 199 | |
| 200 <A NAME="OPTION-U"><B>-U</B></A> <I>userdirs</I> | |
| 201 enables per-user <I>whiteclnt</I> files and log directories. Each target | |
| 202 of a message can have a directory of log files named | |
| 203 <I>userdirs/addr/log</I> where <I>addr</I> is the local user or mailbox name com- | |
| 204 puted by the MTA. The name of each user's log directory must be | |
| 205 <I>log</I>. If it is not absolute, <I>userdirs</I> is relative to the DCC home | |
| 206 directory. The directory containing the log files must be named <I>log</I> | |
| 207 and it must be writable by the <B>dccifd</B> process. Each log directory | |
| 208 must exist or logging for the corresponding is silently disabled. | |
| 209 The files created in the log directory are owned by the UID of the | |
| 210 <B>dccifd</B> process, but they have <I>group</I> and <I>other</I> read and write permis- | |
| 211 sions copied from the corresponding <I>log</I> directory. To ensure the | |
| 212 privacy of mail, it may be good to make the directories readable | |
| 213 only by <I>owner</I> and <I>group</I>, and to use a cron script that changes the | |
| 214 owner of each file to match the grandparent <I>addr</I> directory. | |
| 215 | |
| 216 There can also be a per -user whitelist file named | |
| 217 <I>userdirs/addr/whiteclnt</I> for each address <I>addr.</I> Any checksum that is | |
| 218 not white- or blacklisted by an individual addressee's <I>whiteclnt</I> | |
| 219 file is checked in the main <B>-w -whiteclnt</B> file. A missing per- | |
| 220 addressee <I>whiteclnt</I> file is the same as an empty file. Relative | |
| 221 paths for files included in per-addressee files are resolved in the | |
| 222 DCC home directory. The <I>whiteclnt</I> files and the <I>addr</I> directories | |
| 223 containing them must be writable by the <B>dccifd</B> process. | |
| 224 | |
| 225 <I>Option</I> lines in per-user whiteclnt files can be used to modify many | |
| 226 aspects of <B>dccifd</B> filtering, as described in the main dcc man page. | |
| 227 For example, an <I>option</I> <I>dcc-off</I> line turns off DCC filtering for | |
| 228 individual mailboxes. | |
| 229 | |
| 230 <A NAME="OPTION-a"><B>-a</B></A> <I>IGNORE</I> | <I>REJECT</I> | <I>DISCARD</I> | |
| 231 specifies the action taken when <B>dccifd</B> is in proxy mode with <B>-o</B> and | |
| 232 DCC server counts or <B>-t</B> thresholds say that a message is unsolicited | |
| 233 and bulk. <I>IGNORE</I> causes the message to be unaffected except for | |
| 234 adding the <I>X-DCC</I> header line to the message. This turns off DCC | |
| 235 filtering. | |
| 236 | |
| 237 Spam can also be <I>REJECT</I>ed or (when in proxy mode with <B>-o</B>) accepted | |
| 238 and silently <I>DISCARD</I>ed without being delivered to local mailboxes. | |
| 239 The default is <I>REJECT</I>. | |
| 240 | |
| 241 Mail forwarded via IP addresses marked <I>MX</I> or <I>MXDCC</I> in the main | |
| 242 <I>whiteclnt</I> file is treated as if <B>-a</B> <I>DISCARD</I> were specified. This | |
| 243 prevents "bouncing" spam. | |
| 244 | |
| 245 The effects of the <B>-w</B> <I>whiteclnt</I> are not affected by <B>-a</B>. | |
| 246 | |
| 247 <A NAME="OPTION-t"><B>-t</B></A> <I>type,</I>[<I>log-thold,</I>]<I>rej-thold</I> | |
| 248 sets logging and "spam" thresholds for checksum <I>type</I>. The checksum | |
| 249 types are <I>IP</I>, <I>env</I><B>_</B><I>From</I>, <I>From</I>, <I>Message-ID</I>, <I>substitute</I>, <I>Received</I>, | |
| 250 <I>Body</I>, <I>Fuz1</I>, <I>Fuz2</I>, <I>rep-total</I>, and <I>rep</I>. The first six, <I>IP</I> through | |
| 251 <I>substitute</I>, have no effect except when a local DCC server configured | |
| 252 with <B>-K</B> is used. The <I>substitute</I> thresholds apply to the first sub- | |
| 253 stitute heading encountered in the mail message. The string <I>ALL</I> | |
| 254 sets thresholds for all types, but is unlikely to be useful except | |
| 255 for setting logging thresholds. The string <I>CMN</I> specifies the com- | |
| 256 monly used checksums <I>Body</I>, <I>Fuz1</I>, and <I>Fuz2</I>. <I>Rej-thold</I> and <I>log-thold</I> | |
| 257 must be numbers, the string <I>NEVER</I>, or the string <I>MANY</I> indicating | |
| 258 millions of targets. Counts from the DCC server as large as the | |
| 259 threshold for any single type are taken as sufficient evidence that | |
| 260 the message should be logged or rejected. | |
| 261 | |
| 262 <I>Log-thold</I> is the threshold at which messages are logged. It can be | |
| 263 handy to log messages at a lower threshold to find solicited bulk | |
| 264 mail sources such as mailing lists. If no logging threshold is set, | |
| 265 only rejected mail and messages with complicated combinations of | |
| 266 white and blacklisting are logged. Messages that reach at least one | |
| 267 of their rejection thresholds are logged regardless of logging | |
| 268 thresholds. | |
| 269 | |
| 270 <I>Rej-thold</I> is the threshold at which messages are considered "bulk," | |
| 271 and so should be rejected or discarded if not whitelisted. | |
| 272 | |
| 273 DCC Reputation thresholds in the commercial version of the DCC are | |
| 274 controlled by thresholds on checksum types <I>rep</I> and <I>rep-total</I>. Mes- | |
| 275 sages from an IP address that the DCC database says has sent more | |
| 276 than <B>-t</B> <I>rep-total,log-thold</I> messages are logged. A DCC Reputation | |
| 277 is computed for messages received from IP addresses that have sent | |
| 278 more than <B>-t</B> <I>rep-total,log-thold</I> messages. The DCC Reputation of an | |
| 279 IP address is the percentage of its messages that have been detected | |
| 280 as bulk or having at least 10 recipients. The defaults are equiva- | |
| 281 lent to <B>-t</B> <I>rep,never</I> and <B>-t</B> <I>rep-total,never,20</I>. | |
| 282 | |
| 283 Bad DCC Reputations do not reject mail unless enabled by an <I>option</I> | |
| 284 <I>DCC-rep-on</I> line in a <I>whiteclnt</I> file. | |
| 285 | |
| 286 The checksums of locally whitelisted messages are not checked with | |
| 287 the DCC server and so only the number of targets of the current copy | |
| 288 of a whitelisted message are compared against the thresholds. | |
| 289 | |
| 290 The default is <I>ALL,NEVER</I>, so that nothing is discarded, rejected, or | |
| 291 logged. A common choice is <I>CMN,25,50</I> to reject or discard mail with | |
| 292 common bodies except as overridden by the whitelist of the DCC | |
| 293 server, the sendmail <I>${dcc</I><B>_</B><I>isspam}</I> and <I>${dcc</I><B>_</B><I>notspam}</I> macros, and | |
| 294 <B>-g</B>, and <B>-w</B>. | |
| 295 | |
| 296 <A NAME="OPTION-g"><B>-g</B></A> [<I>not-</I>]<I>type</I> | |
| 297 indicates that whitelisted, <I>OK</I> or <I>OK2</I>, counts from the DCC server | |
| 298 for a type of checksum are to be believed. They should be ignored | |
| 299 if prefixed with <I>not-</I>. <I>Type</I> is one of the same set of strings as | |
| 300 for <B>-t</B>. Only <I>IP</I>, <I>env</I><B>_</B><I>From</I>, and <I>From</I> are likely choices. By default | |
| 301 all three are honored, and hence the need for <I>not-</I>. | |
| 302 | |
| 303 <A NAME="OPTION-S"><B>-S</B></A> <I>hdr</I> | |
| 304 adds to the list of substitute or locally chosen headers that are | |
| 305 checked with the <B>-w</B> <I>whiteclnt</I> file and sent to the DCC server. The | |
| 306 checksum of the last header of type <I>hdr</I> found in the message is | |
| 307 checked. <I>Hdr</I> can be <I>HELO</I> to specify the SMTP envelope HELO value. | |
| 308 <I>Hdr</I> can also be <I>mail</I><B>_</B><I>host</I> to specify the host name from the | |
| 309 Mail_from value in the SMTP envelope. As many as six different sub- | |
| 310 stitute headers can be specified, but only the checksum of the first | |
| 311 of the six will be sent to the DCC server. | |
| 312 | |
| 313 <A NAME="OPTION-l"><B>-l</B></A> <I>logdir</I> | |
| 314 specifies a directory in which files containing copies of messages | |
| 315 processed by <B>dccifd</B> are kept. They can be copied to per-user direc- | |
| 316 tories specified with <B>-U</B>. Information about other recipients of a | |
| 317 message is deleted from the per-user copies. | |
| 318 | |
| 319 See the FILES section below concerning the contents of the files. | |
| 320 See also the <I>option</I> <I>log-subdirectory-{day,hour,minute}</I> lines in | |
| 321 <I>whiteclnt</I> files described in <B><A HREF="dcc.html">dcc(8)</A></B>. | |
| 322 | |
| 323 The directory is relative to the DCC home directory if it is not | |
| 324 absolute | |
| 325 | |
| 326 <A NAME="OPTION-R"><B>-R</B></A> <I>rundir</I> | |
| 327 specifies the "run" directory where the file containing the daemon's | |
| 328 process ID is stored. The default value is <I>@dcc_rundir@</I>. | |
| 329 | |
| 330 <A NAME="OPTION-T"><B>-T</B></A> <I>tmpdir</I> | |
| 331 changes the default directory for temporary files from the default. | |
| 332 The default is the directory specified with <B>-l</B> or the system default | |
| 333 if <B>-l</B> is not used. The system default is often <I>/tmp</I>. | |
| 334 | |
| 335 <A NAME="OPTION-D"><B>-D</B></A> <I>local-domain</I> | |
| 336 specifies a host or domain name by which the system is known. There | |
| 337 can be several <B>-D</B> settings. | |
| 338 | |
| 339 To find the per-user log directory and whitelist for each mail | |
| 340 recipient, <B>dccifd</B> must know each recipient's user name. The ASCII | |
| 341 protocol used between and the MTA includes an optional user name | |
| 342 with each SMTP recipient address. When the user name is absent when | |
| 343 the ASCII protocol is used or when the subset of ESMTP enabled with | |
| 344 <B>-o</B> is used, and when the SMTP recipient address includes an <I>at</I> <I>sign</I> | |
| 345 (@) each mail address is checked against the list of <I>local-domain</I>s. | |
| 346 The part of the recipient address remaining after longest matching | |
| 347 <I>local-domain</I> (if any) is taken as the user name. The match is | |
| 348 anchored at the right or the end of the recipient address. It must | |
| 349 start at a period (.) or <I>at</I> <I>sign</I> (@) in the domain name part of the | |
| 350 address. | |
| 351 | |
| 352 If <I>local-domain</I> starts with an asterisk (*) indicating a wildcard, | |
| 353 preceding sub-domain names are discarded to compute the user name. | |
| 354 Otherwise, the computed user name will include any unmatched sub- | |
| 355 domain names. | |
| 356 | |
| 357 The default value of <I>local-domain</I> when there are no <B>-D</B> settings is | |
| 358 the host name of the system. | |
| 359 | |
| 360 <A NAME="OPTION-r"><B>-r</B></A> <I>rejection-msg</I> | |
| 361 specifies the rejection message in <B>-o</B> proxy mode for unsolicited | |
| 362 bulk mail or for mail temporarily blocked by <I>greylisting</I> when <B>-G</B> is | |
| 363 specified. The first <B>-r</B> <I>rejection-msg</I> replaces the default bulk | |
| 364 mail rejection message, "5.7.1 550 mail %ID from %CIP rejected by | |
| 365 DCC". The second replaces "4.2.1 452 mail %ID from %CIP temporary | |
| 366 greylist embargoed". The third <B>-r</B> <I>rejection-msg</I> replaces the | |
| 367 default SMTP rejection message "5.7.1 550 %ID bad reputation; see | |
| 368 http://commercial-dcc.rhyolite.com/cgi-bin/reps.cgi?tgt=%CIP" for | |
| 369 mail with bad DCC Reputations. If <I>rejection-msg</I> is the zero-length | |
| 370 string, the <B>-r</B> setting is counted but the corresponding message is | |
| 371 not changed. | |
| 372 | |
| 373 <I>Rejection-msg</I> can contain specific information about the mail mes- | |
| 374 sage. The following strings starting with % are replaced with the | |
| 375 corresponding values: | |
| 376 %ID message ID such as the unique part of log file name or | |
| 377 sendmail queue ID | |
| 378 %CIP SMTP client IP address | |
| 379 %BTYPE type of DNS blacklist hit, such as "SMTP client", | |
| 380 "mail_host", or "URL NS" | |
| 381 %BTGT IP address or name declared bad by DNS blacklist | |
| 382 %BPROBE domain name found in DNS blacklist such as | |
| 383 4.3.2.10.example.com | |
| 384 %BRESULT value of the %BPROBE domain name found in DNS black- | |
| 385 list | |
| 386 | |
| 387 A common alternate for the bulk mail rejection message is "4.7.1 451 | |
| 388 Access denied by DCC" to tell the sending mail system to continue | |
| 389 trying. Use a 4yz response with caution, because it is likely to | |
| 390 delay for days a delivery failure message for false positives. If | |
| 391 the rejection message does not start with an RFC 1893 status code | |
| 392 and RFC 2821 reply code, 5.7.1 and 550 or 4.2.1 and 452 are used. | |
| 393 | |
| 394 See also <B>-B</B> <I>set:rej-msg=rejection-msg</I> to set the status message for | |
| 395 mail rejected by DNS blacklists. | |
| 396 | |
| 397 <A NAME="OPTION-j"><B>-j</B></A> <I>maxjobs</I> | |
| 398 limits the number of simultaneous requests that will be processed. | |
| 399 The default value is the maximum number that seems to be possible | |
| 400 given system limits on open files, select() bit masks, and so forth. | |
| 401 Start <B>dccifd</B> with <B>-d</B> and see the starting message in the system log | |
| 402 to see the limit. | |
| 403 | |
| 404 <A NAME="OPTION-B"><B>-B</B></A> <I>dnsbl-option</I> | |
| 405 enables DNS blacklist checks of the SMTP client IP address, SMTP | |
| 406 envelope Mail_From sender domain name, and of host names in URLs in | |
| 407 the message body. Body URL blacklisting has too many false posi- | |
| 408 tives to use on abuse mailboxes. It is less effective than | |
| 409 greylisting with <B><A HREF="dccm.html">dccm(8)</A></B> or <B><A HREF="dccifd.html">dccifd(8)</A></B> but can be useful in situa- | |
| 410 tions where greylisting cannot be used. | |
| 411 | |
| 412 <I>Dnsbl-option</I> is either one of the <B>-B</B> <I>set:option</I> forms or | |
| 413 <B>-B</B> <I>domain</I>[<I>,IPaddr</I>[<I>/xx</I>[<I>,bltype</I>]]] | |
| 414 <I>Domain</I> is a DNS blacklist domain such as example.com that will be | |
| 415 searched. <I>IPaddr</I>[<I>/xxx</I>] is the string "any" an IP address in the DNS | |
| 416 blacklist that indicates that the mail message should be rejected, | |
| 417 or a CIDR block covering results from the DNS blacklist. | |
| 418 "127.0.0.2" is assumed if <I>IPaddr</I> is absent. IPv6 addresses can be | |
| 419 specified with the usual colon (:) notation. Names can be used | |
| 420 instead of numeric addresses. The type of DNS blacklist is speci- | |
| 421 fied by <I>bltype</I> as <I>name</I>, <I>IPv4</I>, or <I>IPv6</I>. Given an envelope sender | |
| 422 domain name or a domain name in a URL of spam.domain.org and a | |
| 423 blacklist of type <I>name</I>, spam.domain.org.example.com will be tried. | |
| 424 Blacklist types of <I>IPv4</I> and <I>IPv6</I> require that the domain name in a | |
| 425 URL sender address be resolved into an IPv4 or IPv6 address. The | |
| 426 address is then written as a reversed string of decimal octets to | |
| 427 check the DNS blacklist, as in 2.0.0.127.example.com, | |
| 428 | |
| 429 More than one blacklist can be specified and blacklists can be | |
| 430 grouped. All searching within a group is stopped at the first posi- | |
| 431 tive result. | |
| 432 | |
| 433 Positive results are ignored after being logged unless an | |
| 434 <I>option</I> <I>DNSBL-on</I> line appears in the global or per-user <I>whiteclnt</I> | |
| 435 file. | |
| 436 | |
| 437 <B>-B</B> <I>set:no-client</I> | |
| 438 says that SMTP client IP addresses and reverse DNS domain names | |
| 439 should not be checked in the following blacklists. | |
| 440 <B>-B</B> <I>set:client</I> restores the default for the following black- | |
| 441 lists. | |
| 442 | |
| 443 <B>-B</B> <I>set:no-mail</I><B>_</B><I>host</I> | |
| 444 says that SMTP envelope Mail_From sender domain names should | |
| 445 not be checked in the following blacklists. <B>-B</B> <I>set:mail</I><B>_</B><I>host</I> | |
| 446 restores the default. | |
| 447 | |
| 448 <B>-B</B> <I>set:no-URL</I> | |
| 449 says that URLs in the message body should not be checked in the | |
| 450 in the following blacklists. <B>-B</B> <I>set:URL</I> restores the default. | |
| 451 | |
| 452 <B>-B</B> <I>set:no-MX</I> | |
| 453 says MX servers of sender Mail_From domain names and host names | |
| 454 in URLs should not be checked in the following blacklists. | |
| 455 <B>-B</B> <I>set:MX</I> restores the default. | |
| 456 | |
| 457 <B>-B</B> <I>set:no-NS</I> | |
| 458 says DNS servers of sender Mail_From domain names and host | |
| 459 names in URLs should not be checked in the following black- | |
| 460 lists. <B>-B</B> <I>set:NS</I> restores the default. | |
| 461 | |
| 462 <B>-B</B> <I>set:defaults</I> | |
| 463 is equivalent to all of <B>-B</B> <I>set:no-temp-fail</I> <B>-B</B> <I>set:client</I> | |
| 464 <B>-B</B> <I>set:mail</I><B>_</B><I>host</I> <B>-B</B> <I>set:URL</I> <B>-B</B> <I>set:MX</I> and <B>-B</B> <I>set:NS</I> | |
| 465 | |
| 466 <B>-B</B> <I>set:group=X</I> | |
| 467 adds later DNS blacklists specified with | |
| 468 <B>-B</B> <I>domain</I>[<I>,IPaddr</I>[<I>/xx</I>[<I>,bltype</I>]]] | |
| 469 to group 1, 2, or 3. | |
| 470 | |
| 471 <B>-B</B> <I>set:debug=X</I> | |
| 472 sets the DNS blacklist logging level | |
| 473 | |
| 474 <B>-B</B> <I>set:msg-secs=S</I> | |
| 475 limits <B>dccifd</B> to <I>S</I> seconds total for checking all DNS black- | |
| 476 lists. The default is 25. | |
| 477 | |
| 478 <B>-B</B> <I>set:URL-secs=S</I> | |
| 479 limits <B>dccifd</B> to at most <I>S</I> seconds resolving and checking any | |
| 480 single URL. The default is 11. Some spam contains dozens of | |
| 481 URLs and that some "spamvertised" URLs contain host names that | |
| 482 need minutes to resolve. Busy mail systems cannot afford to | |
| 483 spend minutes checking each incoming mail message. | |
| 484 | |
| 485 <B>-B</B> <I>set:rej-msg=rejection-msg</I> | |
| 486 sets the SMTP rejection message for the following blacklists. | |
| 487 <I>Rejection-msg</I> must be in the same format as for <B>-r</B>. If | |
| 488 <I>rejection-msg</I> is null, the default is restored. The default | |
| 489 DNS blacklist rejection message is the first message set with | |
| 490 <B>-r</B>. | |
| 491 | |
| 492 <B>-B</B> <I>set:temp-fail</I> | |
| 493 causes <B>dccifd</B> to the MTA to answer the SMTP DATA command with | |
| 494 452 4.2.1 mail %ID from %CIP temporary delayed for DNSBL | |
| 495 if any DNS answer required for a DNSBL in the current group | |
| 496 times out, including resolving names in URLs. | |
| 497 | |
| 498 <B>-B</B> <I>set:no-temp-fail</I> | |
| 499 restores the default of assuming a negative answer for DNS | |
| 500 responses that take too long. | |
| 501 | |
| 502 <B>-B</B> <I>set:maxjobs=X</I> | |
| 503 sets maximum number of helper processes to <I>X</I>. In order to use | |
| 504 typical single-threaded DNS resolver libraries, <B>dccifd</B> uses | |
| 505 fleets of helper processes. It is rarely a good idea to change | |
| 506 the default, which is the same as the maximum number of simul- | |
| 507 taneous jobs set with <B>-j</B>. | |
| 508 | |
| 509 <B>-B</B> <I>set:progpath=@libexecdir@/dns-helper</I> | |
| 510 changes the path to the helper program. | |
| 511 | |
| 512 <A NAME="OPTION-L"><B>-L</B></A> <I>ltype,facility.level</I> | |
| 513 specifies how messages should be logged. <I>Ltype</I> must be <I>error</I>, <I>info</I>, | |
| 514 or <I>off</I> to indicate which of the two types of messages are being con- | |
| 515 trolled or to turn off all <B>syslog(3)</B> messages from <B>dccifd</B>. <I>Level</I> | |
| 516 must be a <B>syslog(3)</B> level among <I>EMERG</I>, <I>ALERT</I>, <I>CRIT</I>, <I>ERR</I>, <I>WARNING</I>, | |
| 517 <I>NOTICE</I>, <I>INFO</I>, and <I>DEBUG</I>. <I>Facility</I> must be among <I>AUTH</I>, <I>AUTHPRIV</I>, | |
| 518 <I>CRON</I>, <I>DAEMON</I>, <I>FTP</I>, <I>KERN</I>, <I>LPR</I>, <I>MAIL</I>, <I>NEWS</I>, <I>USER</I>, <I>UUCP</I>, and <I>LOCAL0</I> | |
| 519 through <I>LOCAL7</I>. The default is equivalent to | |
| 520 <B>-L</B> <I>info,MAIL.NOTICE</I> <B>-L</B> <I>error,MAIL.ERR</I> | |
| 521 | |
| 522 <B>dccifd</B> normally sends counts of mail rejected and so forth to the system | |
| 523 log at midnight. The SIGUSR1 signal sends an immediate report to the | |
| 524 system log. The reports will be repeated every 24 hours at the same | |
| 525 minute as the signal instead of at midnight. | |
| 526 | |
| 527 <A NAME="Protocol"><B>Protocol</B></A> | |
| 528 <B>Dccifd</B> uses a simple ASCII protocol to receive mail messages to be | |
| 529 checked and to return results. For each message, the MTA must open a | |
| 530 connection to the interface daemon, send options, envelope recipients, | |
| 531 and the message, receive the results, and close the connection. | |
| 532 | |
| 533 Instead of the ASCII protocol, a subset of ESMTP is enabled by <B>-o</B>. Only | |
| 534 the familiar HELO, EHLO, Mail, Rcpt, DATA, RSET, and QUIT commands and | |
| 535 the Postfix extensions XFORWARD and XCLIENT are honored. Since SMTP has | |
| 536 no provisions for user names, the protocol enabled by <B>-o</B> depends on a | |
| 537 list of local domain names specified with <B>-D</B> to find per-user log direc- | |
| 538 tories and whitelist files. If neither XFORWARD nor XCLIENT are used, | |
| 539 <B>dccifd</B> uses the IP address of the MTA and the value of the HELO command. | |
| 540 | |
| 541 In the ASCII protocol, each of the following lines are sent in order to | |
| 542 <B>dccifd</B>. Each ends with a newline ('\n') character. | |
| 543 options zero or more blank-separated strings among: | |
| 544 <I>spam</I> the message is already known to be spam | |
| 545 <I>body</I> return all of the headers with the added | |
| 546 <I>X-DCC</I> header line and the body | |
| 547 <I>header</I> return the <I>X-DCC</I> header | |
| 548 <I>query</I> ask the DCC server about the message without | |
| 549 reporting it, as if <B>dccifd</B> were running with | |
| 550 <B>-Q</B>. | |
| 551 <I>grey-query</I> only query the greylist server for this mes- | |
| 552 sage. <B>-G</B> <I>on</I> must be in use. | |
| 553 <I>no-reject</I> suppress the overall, one character line 'R' | |
| 554 result. This can be useful when using <B>dccifd</B> | |
| 555 only for greylisting. | |
| 556 <I>log</I> ensure that this message is logged as if | |
| 557 <B>dccifd</B> were running with <B>-t -all,0,</B> | |
| 558 client IP address of the SMTP client in a "dotted" or "coloned" | |
| 559 ASCII string and reverse-DNS host name. If the host name | |
| 560 is present, it must follow a carriage return character | |
| 561 ('\r') after the IP address. The client IP address must be | |
| 562 present and non-null if the host name is present. The | |
| 563 string "0.0.0.0\n" is understood the same as the null | |
| 564 string, meaning that both the IP address and host name are | |
| 565 absent. If the client IP address is absent, then the IP | |
| 566 address and host name are taken from the first non-local | |
| 567 Received header if it has the standard "name (name [IP | |
| 568 address])..." format. Non-standard Received headers com- | |
| 569 monly added by qmail as well as Received headers specifying | |
| 570 IP addresses marked <I>MX</I> or <I>MXDCC</I> in the global <B>-w</B> <I>whiteclnt</I> | |
| 571 file are skipped. | |
| 572 HELO SMTP HELO value or nothing, followed by a newline ('\n') | |
| 573 character. If the HELO value is null and the IP address of | |
| 574 the SMTP client are not supplied, they will be taken from | |
| 575 the same Received: header that supplies the IP address. | |
| 576 sender or SMTP <I>Mail</I> <I>From</I> command value for the env_from checksum. | |
| 577 If the sender is null, the contents of the first Return- | |
| 578 Path: or UNIX style From_ header is used. | |
| 579 recipients or SMTP <I>Rcpt</I> <I>To</I> recipient mailboxes followed by correspond- | |
| 580 ing local user names, one (mailbox,user) pair to a line. | |
| 581 Each optional local user name is separated from the corre- | |
| 582 sponding mailbox recipient address by a carriage return | |
| 583 ('\r'). A local user name can be null if it is not known, | |
| 584 but each recipient mailbox must be non-null. If there are | |
| 585 no lines of (mailbox,user) pairs and if the <I>spam</I> option is | |
| 586 not included, then the <I>query</I> is assumed. Mailboxes without | |
| 587 user names will lack per-user log files and will not invoke | |
| 588 a per-user whitelist. | |
| 589 | |
| 590 The last recipient-user name pair is followed by an empty line and the | |
| 591 headers and body of the message. The end of the body of the mail message | |
| 592 is signaled by the MTA half-closing the connection. See <B>shutdown(2)</B>. | |
| 593 | |
| 594 <B>Dccifd</B> responds with three things. First is a one character line of the | |
| 595 overall result advising the MTA: | |
| 596 A accept the message for all recipients and answer the SMTP DATA | |
| 597 command with a 2yz result. | |
| 598 G answer with a 4yz result to embargo the message for greylisting. | |
| 599 R reject the message and answer the DATA command with a 5yz result. | |
| 600 S accept the message for some recipients and so answer the DATA com- | |
| 601 mand with a 2yz result. | |
| 602 T temporary failure by the DCC system and so answer with a 4yz | |
| 603 result. | |
| 604 | |
| 605 Second is a line of characters indicating the disposition of the message | |
| 606 for each corresponding recipient: | |
| 607 A deliver the message | |
| 608 G discard the message during a greylist embargo | |
| 609 R discard the message as spam | |
| 610 The SMTP protocol allows only a single result for the DATA command for | |
| 611 all recipients that were not rejected before body of the message was | |
| 612 offered with the DATA command. To accept the message for some recipients | |
| 613 and reject it for others, the MTA must tell the SMTP client it is accept- | |
| 614 ing the message for all recipients and then discard it for those that | |
| 615 would reject it. | |
| 616 | |
| 617 Finally, if the <I>body</I> or <I>header</I> strings are in the first line of <I>options</I> | |
| 618 sent by the MTA to the daemon, then the <I>X-DCC</I> header line or the entire | |
| 619 body with the <I>X-DCC</I> header line follows. | |
| 620 | |
| 621 | |
| 622 </PRE> | |
| 623 <H2><A NAME="FILES">FILES</A></H2><PRE> | |
| 624 <A NAME="FILE-@prefix@">@prefix@</A> is the DCC home directory in which other files are found. | |
| 625 <A NAME="FILE-@libexecdir@/start">@libexecdir@/start</A>-dccifd | |
| 626 and | |
| 627 <A NAME="FILE-@libexecdir@/rcDCC">@libexecdir@/rcDCC</A> | |
| 628 are scripts used to start the daemon. | |
| 629 <A NAME="FILE-dcc/dcc_conf">dcc/dcc_conf</A> | |
| 630 contains parameters used by the scripts to start DCC daemons | |
| 631 and cron jobs. | |
| 632 <A NAME="FILE-logdir">logdir</A> is an optional directory specified with <B>-l</B> and containing | |
| 633 marked mail. Each file in the directory contains one mes- | |
| 634 sage, at least one of whose checksums reached its <B>-t</B> thresh- | |
| 635 olds or that is interesting for some other reason. Each file | |
| 636 starts with lines containing the date when the message was | |
| 637 received, the IP address of the SMTP client, and SMTP enve- | |
| 638 lope values. Those lines are followed by the body of the | |
| 639 SMTP message including its header as it was received. Only | |
| 640 approximately the first 32 KBytes of the body are recorded | |
| 641 unless modified by <I>./configure</I> <I>--with-max-log-size=xx</I> The | |
| 642 checksums for the message follow the body. They are followed | |
| 643 by lines indicate that one of the checksums is white- or | |
| 644 blacklisted by the <B>-w</B> <I>whiteclnt</I> file. Each log file ends | |
| 645 with the <I>X-DCC</I> header line added to the message and the dis- | |
| 646 position of the message. | |
| 647 <A NAME="FILE-map">map</A> is the memory mapped file of information concerning DCC | |
| 648 servers in the DCC home directory. | |
| 649 <A NAME="FILE-whiteclnt">whiteclnt</A> contains the client whitelist in the format described in | |
| 650 <B><A HREF="dcc.html">dcc(8)</A></B>. | |
| 651 <A NAME="FILE-whiteclnt.dccw">whiteclnt.dccw</A> | |
| 652 is a memory mapped hash table of the <I>whiteclnt</I> file. | |
| 653 <A NAME="FILE-dccifd.pid">dccifd.pid</A> in the <B>-R</B> <I>rundir</I> directory contains daemon's process ID. | |
| 654 | |
| 655 | |
| 656 </PRE> | |
| 657 <H2><A NAME="EXAMPLES">EXAMPLES</A></H2><PRE> | |
| 658 Dccifd can be used as Postfix Before-Queue Content filter. In some tests | |
| 659 these values for <B>-p</B> and <B>-o</B> in <I>dcc</I><B>_</B><I>conf</I>. | |
| 660 | |
| 661 DCCIFD_ENABLE=on | |
| 662 DCCIFD_ARGS="-p 127.0.0.1,10025,127.0.0.1/32 -o 127.0.0.1,10026 | |
| 663 | |
| 664 worked with these lines in /etc/postfix/master.cf | |
| 665 | |
| 666 smtp inet n - n - - smtpd | |
| 667 -o smtpd_proxy_filter=127.0.0.1:10025 | |
| 668 127.0.0.1:10026 inet n - n - - smtpd | |
| 669 -o smtpd_authorized_xforward_hosts=127.0.0.0/8 | |
| 670 -o smtpd_client_restrictions= | |
| 671 -o smtpd_helo_restrictions= | |
| 672 -o smtpd_sender_restrictions= | |
| 673 -o smtpd_recipient_restrictions=permit_mynetworks,reject | |
| 674 -o smtpd_data_restrictions= | |
| 675 -o mynetworks=127.0.0.0/8 | |
| 676 -o receive_override_options=no_unknown_recipient_checks | |
| 677 | |
| 678 | |
| 679 </PRE> | |
| 680 <H2><A NAME="SEE-ALSO">SEE ALSO</A></H2><PRE> | |
| 681 <B><A HREF="cdcc.html">cdcc(8)</A></B>, <B><A HREF="dbclean.html">dbclean(8)</A></B>, <B><A HREF="dcc.html">dcc(8)</A></B>, <B><A HREF="dccd.html">dccd(8)</A></B>, <B><A HREF="dblist.html">dblist(8)</A></B>, <B><A HREF="dccm.html">dccm(8)</A></B>, <B><A HREF="dccproc.html">dccproc(8)</A></B>, | |
| 682 <B><A HREF="dccsight.html">dccsight(8)</A></B>, | |
| 683 | |
| 684 | |
| 685 </PRE> | |
| 686 <H2><A NAME="HISTORY">HISTORY</A></H2><PRE> | |
| 687 Implementation of <B>dccifd</B> Distributed Checksum Clearinghouses are based on | |
| 688 an idea of Paul Vixie with code designed and written at Rhyolite Software | |
| 689 starting in 2000. was started at Rhyolite Software in 2002. This docu- | |
| 690 ment describes version 1.3.103. | |
| 691 | |
| 692 | |
| 693 </PRE> | |
| 694 <H2><A NAME="BUGS">BUGS</A></H2><PRE> | |
| 695 <B>dccifd</B> uses <B>-t</B> where <B><A HREF="dccproc.html">dccproc(8)</A></B> uses <B>-c</B>. | |
| 696 | |
| 697 By default <B>dccifd</B> look for its UNIX domain socket in the DCC home direc- | |
| 698 tory, but <B><A HREF="dccm.html">dccm(8)</A></B> looks in its <B>-R</B> <I>rundir</I>. | |
| 699 | |
| 700 Systems without <B>setrlimit(2)</B> and <B>getrlimit(2)</B> RLIMIT_NOFILE can have | |
| 701 problems with the default limit on the number of simultaneous jobs, the | |
| 702 value of <B>-j</B>. Every job requires four open files. These problems are | |
| 703 usually seen with errors messages that say something like | |
| 704 dccifd[24448]: DCC: accept(): Result too large | |
| 705 A fix is to use a smaller value for <B>-j</B> or to allow <B>dccifd</B> to open more | |
| 706 files. | |
| 707 | |
| 708 February 26, 2009 | |
| 709 </PRE> | |
| 710 <HR> | |
| 711 <ADDRESS> | |
| 712 Man(1) output converted with | |
| 713 <a href="http://www.oac.uci.edu/indiv/ehood/man2html.html">man2html</a> | |
| 714 modified for the DCC $Date 2001/04/29 03:22:18 $ | |
| 715 <BR> | |
| 716 <A HREF="http://www.dcc-servers.net/dcc/"> | |
| 717 <IMG SRC="http://logos.dcc-servers.net/border.png" | |
| 718 class=logo ALT="DCC logo"> | |
| 719 </A> | |
| 720 <A HREF="http://validator.w3.org/check?uri=referer"> | |
| 721 <IMG class=logo ALT="Valid HTML 4.01 Strict" | |
| 722 SRC="http://www.w3.org/Icons/valid-html401"> | |
| 723 </A> | |
| 724 </ADDRESS> | |
| 725 </BODY> | |
| 726 </HTML> |