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diff --git a/doc/proxsmtpd.8 b/doc/proxsmtpd.8 deleted file mode 100644 index 9f9f9d0..0000000 --- a/doc/proxsmtpd.8 +++ /dev/null @@ -1,213 +0,0 @@ -.\" -.\" Copyright (c) 2004, Nate Nielsen -.\" All rights reserved. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" -.\" * Redistributions of source code must retain the above -.\" copyright notice, this list of conditions and the -.\" following disclaimer. -.\" * Redistributions in binary form must reproduce the -.\" above copyright notice, this list of conditions and -.\" the following disclaimer in the documentation and/or -.\" other materials provided with the distribution. -.\" * The names of contributors to this software may not be -.\" used to endorse or promote products derived from this -.\" software without specific prior written permission. -.\" -.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -.\" "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT -.\" LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS -.\" FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE -.\" COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, -.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, -.\" BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS -.\" OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED -.\" AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, -.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF -.\" THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH -.\" DAMAGE. -.\" -.\" -.\" CONTRIBUTORS -.\" Nate Nielsen <nielsen@memberwebs.com> -.\" -.Dd September, 2004 -.Dt proxsmtpd 8 -.Os proxsmtp -.Sh NAME -.Nm proxsmtpd -.Nd an SMTP server for performing filtering -.Sh SYNOPSIS -.Nm -.Op Fl d Ar level -.Op Fl f Ar configfile -.Op Fl p Ar pidfile -.Nm -.Fl v -.Sh DESCRIPTION -.Nm -is an SMTP filter that allows you to perform arbitrary filtering on email. It -accepts SMTP connections and forwards the SMTP commands and responses to another -SMTP server. -.Pp -The DATA email body is intercepted and scanned before forwarding. Email can be -altered, bounced, or silently dropped. -.Pp -.Nm -aims to be lightweight and simple rather than have a myriad of options. The options -it does have are configured by editing the -.Xr proxsmtpd.conf 5 -file. See the man page for -.Xr proxsmtpd.conf 5 -for more info on the default location of the configuration file. -.Sh OPTIONS -The options are as follows. -.Bl -tag -width Fl -.It Fl d -Don't detach from the console and run as a daemon. In addition the -.Ar level -argument specifies what level of error messages to display. 0 being -the least, 4 the most. -.It Fl f -.Ar configfile -specifies an alternate location for the -.Nm -configuration file. See -.Xr proxsmtpd.conf 5 -for more details on where the configuration file is located by default. -.It Fl p -.Ar pidfile -specifies a location for the a process id file to be written to. This file -contains the process id of -.Nm -and can be used to stop the daemon. -.It Fl v -Prints the proxsmtp version number and exits. -.El -.Sh FILTER SCRIPTS -The filter script is specified using the -.Ar FilterCommand -option. By default the email is piped through the script on standard input. -Standard output is read for the filtered email. Standard error is also read -for error messages. -.Pp -If the -.Ar FilterType -option is set to 'file', your filter will operate on a file rather than processing -standard in and standard out. The file name will be passed to your filter -command using the -.Ar EMAIL -environment variable. Your script can change the file as needed. Standard error -is still processed as outlined below. -.Pp -If the filter command returns a successful exit code (ie: 0), then the filtered -email is sent to the destination mail server as usual. When a error exit code -(ie: anything but 0) a failure message is sent back to the sending server. In -this case the email is not sent. -.Pp -You can customize the error message sent back. The last line of output printed -to standard error will be used in this case. If you specify a full SMTP error -code then it will be used (ie: '550 Bad Email'). If it's just a text message -then a 550 SMTP error code will be used. -.Pp -You can silently drop messages by using an error message with a 250 SMTP code. -This gives the illusion to the sending server that the email was accepted. -.Pp -Various environment variables will be present when your script is run. You -may need to escape them properly before use in your favorite scripting -language. Failure to do this could lead to a REMOTE COMPROMISE of your -machine. -.Bl -tag -width Fl -.It Ar CLIENT -The network address of the SMTP client connected. -.It Ar EMAIL -When the -.Ar FilterType -option is set to 'file', this specifies the file that the email was saved to. -.It Ar RECIPIENTS -The email addresses of the email recipients. These are specified one per -line, in standard address format. -.It Ar SENDER -The email address for the sender of the email. -.It Ar SERVER -The network address of the SMTP server we're connected to. -.It Ar TMPDIR -The path to the temp directory in use. This is the same as the -.Ar TempDirectory -option. -.El -.Sh LOGGING -.Nm -logs to -.Xr syslogd -by default under the 'mail' facility. You can also output logs to the console -using the -.Fl d -option. -.Sh LOOPBACK FEATURE -In some cases it's advantageous to consolidate the filtering for several mail -servers on one machine. -.Nm -allows this by providing a loopback feature to connect back to the IP that an -SMTP connection comes in from. -.Pp -To use this feature specify only a port number (no IP address) for the -.Ar OutAddress -setting in the configuration file. This will cause -.Nm -to pass the email back to the said port on the incoming IP address. -.Pp -Make sure the -.Ar MaxConnections -setting is set high enough to handle the mail from all the servers without refusing -connections. -.Sh TRANSPARENT PROXY FEATURE -A transparent proxy is a configuration on a gateway that routes certain types of -traffic through a proxy server without any changes on the client computers. -.Nm -has support for transparent proxying of SMTP traffic by enabling the -.Ar TransparentProxy -setting. This type of setup usually involves firewall rules which redirect traffic to -.Nm -and the setup varies from OS to OS. The SMTP traffic will be forwarded to it's -original destination after being scanned. -.Pp -Note that some features (such as SSL/TLS) will not be available -when going through the transparent proxy. -.Pp -Make sure that the -.Ar MaxConnections -setting is set high enough for your transparent proxying. Because -.Nm -is not being used as a filter inside a queue, which usually throttles the amount -of email going through, this setting may need to be higher than usual. -.Sh SECURITY -There's no reason to run this daemon as root. It is meant as a filter and should -listen on a high TCP port. -.Pp -Care should be taken with the directory that -.Nm -writes its temporary files to. In order to be secure, it should not be a world -writeable location. Specify the directory using the -.Ar TempDirectory -setting. -.Pp -Make sure you understand the issues involved with escaping external data. The -environment variables such as -.Ar SENDER -or -.Ar RECIPIENTS -need to be treated with care. -.Pp -If running -.Nm -on a publicly accessible IP address or without a firewall please be sure to -understand all the possible security issues. This is especially true if the -loopback feature is used (see above). -.Sh SEE ALSO -.Xr proxsmtpd.conf 5 -.Sh AUTHOR -.An Nate Nielsen Aq nielsen@memberwebs.com |