Count configuration file lines for better error reporting.

On Windows, select() ignores its first argument and instead relies on a
slightly different fd_set structure that can hold file descriptors with
arbitrary values. We use the Microsoft recommended way and just increase
FD_SETSIZE at compilation time.

.travis.yml

@@ -0,0 +1,21 @@
+sudo: false
+language: c
+env: VERBOSE=1
+
+addons:
+  apt:
+    packages:
+      - build-essential
+      - pkg-config
+
+before_install:
+  - ./bootstrap
+
+os:
+  - linux
+  - osx
+
+compiler:
+  - gcc
+  - clang
+

CHANGES

@@ -1,55 +0,0 @@
-Version 0.1: original version.
-
-Version 0.2: fixed bug when several reads are necessary
-on one end or the other before a write flushes them.
-Fixed bug which threw away data not yet sent to the
-other side on close, when running under Linux. Fixed
-associated bugs that probably affected other operating
-systems as well. Fixed bug causing long, perhaps
-indefinite pauses when a possible connection to a
-server socket went away before the accept() call,
-resulting in a blocking call.
-
-Version 0.3: fixed additional bugs relating to
-the code previously used only by non-Linux OSes.
-This should fix problems such as connections not
-going away when they should or connections being
-mysteriously closed. Most of that code is now used by 
-Linux also, so it is likely that rinetd is much closer 
-to bug-free on non-Linux platforms. Of course, I don't 
-actually have any to play with it on.
-
-Version 0.4: added support for kill -1 (SIGHUP)
-and specification of service names instead of
-port numbers. Removed calls to realloc(), replacing
-them with code that should fail gracefully without
-crashing the program or breaking existing connections
-when another application is hogging memory.
-
-Version 0.5: added logging in both tab-delimited
-and web-server-style formats. No longer exits if
-an individual configuration file line generates
-an error. Added allow and deny rules. Added 
--c command line option to specify a configuration file.
-
-Version 0.51: fixed failure to check for an open
-log file before writing log entries.
-
-Version 0.52: documentation added regarding the
-ability to bind to all IP addresses, if desired,
-using the special address 0.0.0.0.
-
-Version 0.6: ported to Win32. Various compatibility
-fixes were made and some minor oversights without
-functional consequences were corrected.
-
-Version 0.61: fixed a bug in 0.6 which completely
-broke rinetd under Linux. Oops.
-
-Version 0.62: fixed a potential buffer overrun;
-prior versions failed to reallocate one of the
-arrays correctly when reallocating memory to
-accommodate more connections.  Thanks to 
-Sam Hocevar.
-
-

CHANGES.md

@@ -0,0 +1,73 @@
+## Version 0.63
+
+ * added a `-f` flag to run in the foreground
+ * quit cleanly when `SIGINT` is received
+ * increased data buffer size for better performance
+ * fixed random uninitialised data accesses
+ * fixed a memory leak in connection reallocation
+ * fixed a file descriptor leak in configuration reload
+ * fixed configuration file parsing (many bugs including a buffer overflow)
+ * fixed configuration error reporting (line numbers were wrong)
+ * log accepted connections in addition to denied ones
+ * log DNS errors
+ * code quality refactoring: got rid of a lot of old code, used C
+   library functions instead of custom ones, enforced `const` correctness
+
+## Version 0.62
+
+fixed a potential buffer overrun; prior versions failed to reallocate one of
+the arrays correctly when reallocating memory to accommodate more connections.
+Thanks to Sam Hocevar.
+
+## Version 0.61
+
+fixed a bug in 0.6 which completely broke rinetd under Linux. Oops.
+
+## Version 0.6
+
+ported to Win32. Various compatibility fixes were made and some minor
+oversights without functional consequences were corrected.
+
+## Version 0.52
+
+documentation added regarding the ability to bind to all IP addresses, if
+desired, using the special address 0.0.0.0.
+
+## Version 0.51
+
+fixed failure to check for an open log file before writing log entries.
+
+## Version 0.5
+
+added logging in both tab-delimited and web-server-style formats. No longer
+exits if an individual configuration file line generates an error. Added allow
+and deny rules. Added -c command line option to specify a configuration file.
+
+## Version 0.4
+
+added support for kill -1 (SIGHUP) and specification of service names instead
+of port numbers. Removed calls to realloc(), replacing them with code that
+should fail gracefully without crashing the program or breaking existing
+connections when another application is hogging memory.
+
+## Version 0.3
+
+fixed additional bugs relating to the code previously used only by non-Linux
+OSes. This should fix problems such as connections not going away when they
+should or connections being mysteriously closed. Most of that code is now
+used by Linux also, so it is likely that rinetd is much closer to bug-free on
+non-Linux platforms. Of course, I don't actually have any to play with it on.
+
+## Version 0.2
+
+fixed bug when several reads are necessary on one end or the other before a
+write flushes them. Fixed bug which threw away data not yet sent to the other
+side on close, when running under Linux. Fixed associated bugs that probably
+affected other operating systems as well. Fixed bug causing long, perhaps
+indefinite pauses when a possible connection to a server socket went away
+before the accept() call, resulting in a blocking call.
+
+## Version 0.1
+
+original version.
+

Makefile.am

@@ -1,13 +1,26 @@
 
 AUTOMAKE_OPTIONS = foreign dist-bzip2
 
-EXTRA_DIST = bootstrap CHANGES index.html \
+EXTRA_DIST = bootstrap CHANGES.md README.md index.html \
 	getopt.c getopt.h $(man_MANS) $(sysconf_DATA)
 
 man_MANS = rinetd.8
 sysconf_DATA = rinetd.conf
 
 sbin_PROGRAMS = rinetd
-rinetd_SOURCES = rinetd.c match.c match.h
-rinetd_CFLAGS = -Wall -Wwrite-strings -I.
+rinetd_SOURCES = rinetd.c rinetd.h parse.h match.c match.h
+
+GENERATED_SOURCES = parse.h
+
+# If peg/leg is available, regenerate parse.h
+parse.h: parse.peg
+	if which leg >/dev/null 2>&1; then leg -o $@ $^; else touch $@; fi
+
+# _POSIX_C_SOURCE is for SA_RESTART and others
+# _XOPEN_SOURCE is for struct sigaction
+# _GNU_SOURCE is for h_errno and gethostbyname-related macros
+rinetd_CFLAGS = -std=c99 -D_XOPEN_SOURCE -D_GNU_SOURCE -D_POSIX_C_SOURCE=200809L -Wall -Wextra -Wwrite-strings -I.
+
+# This is for Travis CI; we don’t have a testsuite yet.
+test:
 

README

@@ -1,14 +0,0 @@
-rinetd, by Thomas Boutell. Released under the terms of the GNU General
-Public License, version 2 or later.
-
-This program is used to efficiently redirect connections from one IP
-address/port combination to another. It is useful when operating virtual
-servers, firewalls and the like.
-
-To build under Unix, run "./bootstrap" to create the configuration
-files, then "./configure" to create the build files, and then type
-"make" to build rinetd. To install, type "make install" as root.
-
-For documentation run "make install", then type "man rinetd" for
-details. Or, read index.html in your browser.
-

README.md

@@ -0,0 +1,14 @@
+rinetd, by Thomas Boutell and Sam Hocevar. Released under the terms
+of the GNU General Public License, version 2 or later.
+
+This program is used to efficiently redirect connections from one IP
+address/port combination to another. It is useful when operating virtual
+servers, firewalls and the like.
+
+To build under Unix, run `./bootstrap` to create the configuration
+files, then `./configure` to create the build files, and then type
+`make` to build rinetd. To install, type `make install` as root.
+
+For documentation run `make install`, then type `man rinetd` for
+details. Or, read `index.html` in your browser.
+

configure.ac

@@ -1,6 +1,6 @@
 # Process this file with autoconf to produce a configure script.
 AC_PREREQ(2.52)
-AC_INIT(rinetd, 0.62.0sam, sam@hocevar.net)
+AC_INIT(rinetd, 0.63, sam@hocevar.net)
 AC_CONFIG_AUX_DIR(.auto)
 AC_CONFIG_SRCDIR([getopt.h])
 AC_CONFIG_HEADER([config.h])
@@ -11,6 +11,7 @@ AC_PROG_CC
 AC_PROG_INSTALL
 
 # Checks for libraries.
+AC_CHECK_LIB(ws2_32, main, [LIBS="${LIBS} -lws2_32"])
 
 # Checks for header files.
 AC_HEADER_STDC
@@ -26,10 +27,11 @@ AC_CHECK_TYPES(socklen_t, [], [],
 
 # Checks for library functions.
 AC_FUNC_FORK
-AC_FUNC_MALLOC
+#XXX: disabled because of cross-compilation issues
+#AC_FUNC_MALLOC
 AC_TYPE_SIGNAL
 AC_FUNC_STRFTIME
-AC_CHECK_FUNCS([gethostbyname memset select socket strstr daemon sigaction])
+AC_CHECK_FUNCS([gethostbyname memset select socket strstr daemon fork sigaction])
 
 AC_CONFIG_FILES([Makefile])
 AC_OUTPUT

index.html

@@ -1,244 +1,232 @@
 <html>
 <head>
 <title>RINETD(8)</title>
+<style>
+body {
+  background-color: #fffff0;
+}
+h3 {
+  color: #ff8888;
+}
+blockquote,code {
+  font-family: consolas, monospace, fixed;
+  font-size: 0.9em;
+  font-weight: bold;
+  color: #555555;
+}
+</style>
 </head>
-<body bgcolor="#FFFFF0">
+<body>
 <!--
  Copyright (c) 1997, 1998, 1999, Thomas Boutell and Boutell.Com, Inc.
  This software is released for free use under the terms of
  the GNU General Public License, version 2 or higher.
 -->
 <table>
-<tr>
-<th width=33% align=left>RINETD(8)
-<th width=33% align=right>Unix System Manager's Manual
-<th width=33% align=right>RINETD(8)
-</tr>
+ <tr>
+  <th width=33% align=left>RINETD(8)
+  <th width=33% align=right>Unix System Manager's Manual
+  <th width=33% align=right>RINETD(8)
+ </tr>
 </table>
-<p>
-<font color="#FF8888" size="4">NAME</font>
-<p>
-rinetd -- internet ``redirection server''
-<p>
-<font color="#FF8888" size="4">SYNOPSIS</font>
-<p>
-<code>/usr/sbin/rinetd</code>
-<p>
-<font color="#FF8888" size="4">VERSION</font>
-<p>
-Version 0.62, 04/13/2003. Version 0.62 corrects a potential
-buffer overflow when reallocating memory to accommodate more
-connections. Upgrading is strongly recommended.
-<p>
-<font color="#FF8888" size="4">WHERE TO GET</font>
-<p>
-<strong>For Linux:</strong>
-<a href="ftp://ftp.boutell.com/pub/boutell/rinetd/rinetd.tar.gz">By
-anonymous FTP from ftp.boutell.com</a> in the subdirectory
-<code>boutell/rinetd</code> as the file <code>rinetd.tar.gz</code>.
-<p>
-<strong>For Windows 95/98/NT:</strong>
-<a href="ftp://ftp.boutell.com/pub/boutell/rinetd/rinetd.zip">By
-anonymous FTP from ftp.boutell.com</a> in the subdirectory
-<code>boutell/rinetd</code> as the file <code>rinetd.zip</code>.
-<p>
-<font color="#FF8888" size="4">DESCRIPTION</font>
-<p>
-Redirects TCP connections from one IP address and port to another. rinetd
-is a single-process server which handles any number of connections to
-the address/port pairs specified in the file <code>/etc/rinetd.conf</code>. 
-Since rinetd runs as a single process using nonblocking I/O, it is
-able to redirect a large number of connections without a severe
-impact on the machine. This makes it practical to run TCP services
-on machines inside an IP masquerading firewall. rinetd <strong>does not
-redirect FTP,</strong> because FTP requires more than one socket.
-<p>
-rinetd is typically launched at boot time, using the following syntax:
-<p>
-<code>/usr/sbin/rinetd</code>
-<p>
-The configuration file is found in the file 
-<code>/etc/rinetd.conf</code>, unless
-another file is specified using the <code>-c</code> command line option. 
-<p>
-<font color="#FF8888" size="4">FORWARDING RULES</font>
-<p>
-Most entries in the configuration file are forwarding rules. The
-format of a forwarding rule is as follows:
-<pre>
-bindaddress bindport connectaddress connectport
-</pre>
-For example:
-<pre>
-206.125.69.81 80 10.1.1.2 80
-</pre>
-Would redirect all connections to port 80 of the "real" IP address
-206.125.69.81, which could be a virtual interface, through
-rinetd to port 80 of the address 10.1.1.2, which would typically 
-be a machine on the inside of a firewall which has no
-direct routing to the outside world.
-<p>
-Although responding on individual interfaces rather than on all
-interfaces is one of rinetd's primary features, sometimes it is 
-preferable to respond on all IP addresses that belong to the server.
-In this situation, the special IP address <code>0.0.0.0</code>
-can be used. For example:
-<pre>
-0.0.0.0 23 10.1.1.2 23
-</pre>
-Would redirect all connections to port 23, for all IP addresses
-assigned to the server. This is the default behavior for most
-other programs.
-<p>
-Service names can be specified instead of port numbers. On most systems,
-service names are defined in the file /etc/services.
-<p>
-Both IP addresses and hostnames are accepted for
-bindaddress and connectaddress.
-<p>
-<font color="#FF8888" size="4">ALLOW AND DENY RULES</font>
-<p>
-Configuration files can also contain allow and deny rules. 
-<p>
-Allow rules which appear before the first forwarding rule are
-applied globally: if at least one global allow rule exists,
-and the address of a new connection does not
-satisfy at least one of the global allow rules, that connection
-is immediately rejected, regardless of any other rules. 
-<p>
-Allow rules which appear after a specific forwarding rule apply 
-to that forwarding rule only. If at least one allow rule
-exists for a particular forwarding rule, and the address of a new
-connection does not satisfy at least one of the allow rules
-for that forwarding rule, that connection is immediately
-rejected, regardless of any other rules.
-<p>
-Deny rules which appear before the first forwarding rule are
-applied globally: if the address of a new connection satisfies
-any of the global allow rules, that connection
-is immediately rejected, regardless of any other rules. 
-<p>
-Deny rules which appear after a specific forwarding rule apply 
-to that forwarding rule only. If the address of a new
-connection satisfies any of the deny rules for that forwarding rule, 
-that connection is immediately rejected, regardless of any other rules.
-<p>
-The format of an allow rule is as follows:
-<pre>
-allow pattern
-</pre>
-Patterns can contain the following characters: 0, 1, 2, 3, 4, 5,
-6, 7, 8, 9, . (period), ?, and *. The ? wildcard matches any one
-character. The * wildcard matches any number of characters, including
-zero. 
-<p>
-For example:
-<p>
-<pre>
-allow 206.125.69.*
-</pre>
-This allow rule matches all IP addresses in the 206.125.69 class C domain.
-<p>
-Host names are NOT permitted in allow and deny rules. The performance
-cost of looking up IP addresses to find their corresponding names
-is prohibitive. Since rinetd is a single process server, all other
-connections would be forced to pause during the address lookup.
-<p>
-<font color="#FF8888" size="4">LOGGING</font>
-<p>
-rinetd is able to produce a log file in either of two formats:
-tab-delimited and web server-style "common log format."
-<p>
-By default, rinetd does not produce a log file. To activate logging, add 
-the following line to the configuration file:
-<pre>
-logfile log-file-location
-</pre>
-Example:
-<pre>
-logfile /var/log/rinetd.log
-</pre>
-By default, rinetd logs in a simple tab-delimited format containing
-the following information:
-<p>
-Date and time<br>
-Client address<br>
 
-Listening host
-<br>
-Listening port
-<br>
-Forwarded-to host
-<br>
-Forwarded-to port
-<br>
-Bytes received from client
-<br>
-Bytes sent to client
-<br>
-Result message
-<p>
-To activate web server-style "common log format" logging,
-add the following line to the configuration file:
-<pre>
-logcommon
-</pre>
-<p>
-<font color="#FF8888" size="4">COMMAND LINE OPTIONS</font>
-<p>
-The -c command line option is used to specify an alternate
-configuration file.
-<p>
-The -f command line option is used to run rinetd in the
-foreground, without forking to the background.
-<p>
-The -h command line option produces a short help message.
-<p>
-The -v command line option displays the version number.
-<p>
-<font color="#FF8888" size="4">REINITIALIZING RINETD</font>
-<p>
-The kill -1 signal (SIGHUP) can be used to cause rinetd
-to reload its configuration file <strong>without</strong> interrupting existing
-connections. Under Linux(tm) the process id 
-is saved in the file <code>/var/run/rinetd.pid</code>
-to facilitate the kill -HUP. An alternate
-file name can be provided by using the <code>pidlogfile</code> 
-configuration file option.
-<p>
-<font color="#FF8888" size="4">BUGS</font>
-<p>
-The server redirected to is not able to identify the host the
-client really came from. This cannot be corrected; however,
-the log produced by rinetd provides a way to obtain this
-information. Under Unix, sockets would theoretically lose data when closed
-with <code>SO_LINGER</code> turned off, but in Linux this is not the case 
-(kernel source comments support this belief on my part). On non-Linux Unix
-platforms, alternate code which uses a different trick to work around 
-blocking <code>close()</code> is provided, but this code is untested.
-<p>
-The logging is inadequate. The duration of the connection should be logged.
-<p>
-<font color="#FF8888" size="4">LICENSE</font>
-<p>
-Copyright (c) 1997, 1998, 1999,
-<a href="http://www.boutell.com/boutell">Thomas Boutell</a> and 
-<a href="http://www.boutell.com/">Boutell.Com, Inc.</a>
-This software is released for free use under the terms of
-the GNU General Public License, version 2 or higher.
-<p>
-<font color="#FF8888" size="4">CONTACT INFORMATION</font>
-<p>
-See <a href="http://www.boutell.com/rinetd">the rinetd web page</a> 
-for the latest release.
-Thomas Boutell can be reached by email: 
-<a href="mailto:boutell@boutell.com">boutell@boutell.com</a>
-<p>
-<font color="#FF8888" size="4">THANKS</font>
-<p>
-Thanks are due to Bill Davidsen, Libor Pechachek, Sascha Ziemann, 
-Joel S. Noble, the Apache Group, and many others who have contributed 
-advice, encouragement and/or source code to this and other open 
-software projects.
+<h3>NAME</h3>
+
+<p> rinetd -- internet “redirection server”</p>
+
+<h3>SYNOPSIS</h3>
+
+<p> <code>/usr/sbin/rinetd</code></p>
+
+<h3>VERSION</h3>
+
+<p> Version 0.63, 2017/07/19. Version 0.63 corrects several bugs including a
+denial of service security issue, and greatly improves performance, ease of
+use, and portability. </p>
+
+<h3>WHERE TO GET</h3>
+ <p> <a href="https://github.com/samhocevar/rinetd/releases">By HTTP on
+GitHub</a> in the releases section. </p>
+
+<h3>DESCRIPTION</h3>
+
+<p> Redirects TCP connections from one IP address and port to another. rinetd
+is a single-process server which handles any number of connections to the
+address/port pairs specified in the file <code>/etc/rinetd.conf</code>. Since
+rinetd runs as a single process using nonblocking I/O, it is able to redirect
+a large number of connections without a severe impact on the machine. This
+makes it practical to run TCP services on machines inside an IP masquerading
+firewall. rinetd <strong>does not redirect FTP</strong>, because FTP requires
+more than one socket. </p>
+
+<p> rinetd is typically launched at boot time, using the following syntax: </p>
+
+<blockquote>/usr/sbin/rinetd</blockquote>
+
+<p> The configuration file is found in the file <code>/etc/rinetd.conf</code>,
+unless another file is specified using the <code>-c</code> command line option.
+</p>
+
+<h3>FORWARDING RULES</h3>
+
+<p> Most entries in the configuration file are forwarding rules. The format of
+a forwarding rule is as follows:
+  <blockquote>bindaddress bindport connectaddress connectport</blockquote>
+For example:
+  <blockquote>206.125.69.81 80 10.1.1.2 80</blockquote>
+Would redirect all connections to port 80 of the “real” IP address
+206.125.69.81, which could be a virtual interface, through rinetd to port 80
+of the address 10.1.1.2, which would typically be a machine on the inside of a
+firewall which has no direct routing to the outside world. </p>
+
+<p> Although responding on individual interfaces rather than on all interfaces
+is one of rinetd's primary features, sometimes it is preferable to respond on
+all IP addresses that belong to the server. In this situation, the special IP
+address <code>0.0.0.0</code> can be used. For example:
+  <blockquote>0.0.0.0 23 10.1.1.2 23</blockquote>
+Would redirect all connections to port 23, for all IP addresses assigned to the
+server. This is the default behavior for most other programs. </p>
+
+<p> Service names can be specified instead of port numbers. On most systems,
+service names are defined in the file /etc/services. </p>
+
+<p> Both IP addresses and hostnames are accepted for bindaddress and
+connectaddress. </p>
+
+<h3>ALLOW AND DENY RULES</h3>
+
+<p> Configuration files can also contain allow and deny rules. </p>
+
+<p> Allow rules which appear before the first forwarding rule are applied
+globally: if at least one global allow rule exists, and the address of a new
+connection does not satisfy at least one of the global allow rules, that
+connection is immediately rejected, regardless of any other rules. </p>
+
+<p> Allow rules which appear after a specific forwarding rule apply to that
+forwarding rule only. If at least one allow rule exists for a particular
+forwarding rule, and the address of a new connection does not satisfy at least
+one of the allow rules for that forwarding rule, that connection is immediately
+rejected, regardless of any other rules. </p>
+
+<p> Deny rules which appear before the first forwarding rule are applied
+globally: if the address of a new connection satisfies any of the global deny
+rules, that connection is immediately rejected, regardless of any other rules.
+</p>
+
+<p> Deny rules which appear after a specific forwarding rule apply to that
+forwarding rule only. If the address of a new connection satisfies any of the
+deny rules for that forwarding rule, that connection is immediately rejected,
+regardless of any other rules. </p>
+
+<p> The format of an allow rule is as follows:
+  <blockquote>allow pattern</blockquote>
+Patterns can contain the following characters: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, .
+(period), ?, and *. The ? wildcard matches any one character. The * wildcard
+matches any number of characters, including zero. </p>
+
+<p> For example: </p>
+
+<p> <blockquote>allow 206.125.69.*</blockquote>
+This allow rule matches all IP addresses in the 206.125.69 class C domain. </p>
+
+<p> Host names are NOT permitted in allow and deny rules. The performance cost
+of looking up IP addresses to find their corresponding names is prohibitive.
+Since rinetd is a single process server, all other connections would be forced
+to pause during the address lookup. </p>
+
+<h3>LOGGING</h3>
+
+<p> rinetd is able to produce a log file in either of two formats:
+tab-delimited and web server-style “common log format.” </p>
+
+<p> By default, rinetd does not produce a log file. To activate logging, add
+the following line to the configuration file:
+  <blockquote>logfile log-file-location</blockquote>
+Example:
+  <blockquote>logfile /var/log/rinetd.log</blockquote>
+By default, rinetd logs in a simple tab-delimited format containing the
+following information: </p>
+
+<ul>
+ <li> Date and time </li>
+ <li> Client address<br />
+ <li> Listening host </li>
+ <li> Listening port </li>
+ <li> Forwarded-to host </li>
+ <li> Forwarded-to port </li>
+ <li> Bytes received from client </li>
+ <li> Bytes sent to client </li>
+ <li> Result message </li>
+</ul>
+
+<p> To activate web server-style “common log format” logging, add the following
+line to the configuration file:
+  <blockquote>logcommon</blockquote>
+</p>
+
+<h3>COMMAND LINE OPTIONS</h3>
+
+<p> The -c command line option is used to specify an alternate configuration
+file. </p>
+
+<p> The -f command line option is used to run rinetd in the foreground, without
+forking to the background. </p>
+
+<p> The -h command line option produces a short help message. </p>
+
+<p> The -v command line option displays the version number. </p>
+
+<h3>REINITIALIZING RINETD</h3>
+
+<p> The kill -1 signal (SIGHUP) can be used to cause rinetd to reload
+its configuration file <strong>without</strong> interrupting existing
+connections. Under Linux(tm) the process id is saved in the file
+<code>/var/run/rinetd.pid</code> to facilitate the kill -HUP. An alternate file
+name can be provided by using the <code>pidlogfile</code> configuration file
+option. </p>
+
+<h3>BUGS</h3>
+
+<p> The server redirected to is not able to identify the host the client
+really came from. This cannot be corrected; however, the log produced by
+rinetd provides a way to obtain this information. Under Unix, sockets would
+theoretically lose data when closed with <code>SO_LINGER</code> turned off, but
+in Linux this is not the case (kernel source comments support this belief on
+my part). On non-Linux Unix platforms, alternate code which uses a different
+trick to work around blocking <code>close()</code> is provided, but this code
+is untested. </p>
+
+<p> The logging is inadequate. The duration of the connection should be logged.
+</p>
+
+<h3>LICENSE</h3>
+
+<p> Copyright (c) 1997, 1998, 1999,
+<a href="http://www.boutell.com/boutell">Thomas Boutell</a> and
+<a href="http://www.boutell.com/">Boutell.Com, Inc.</a> </p>
+
+<p> Copyright (c) 2003&mdash;2017 <a href="https://github.com/samhocevar">Sam
+Hocevar</a> </p>
+
+<p> This software is released for free use under the terms of the GNU
+General Public License, version 2 or higher. </p>
+
+<h3>CONTACT INFORMATION</h3>
+
+<p> See <a href="https://github.com/samhocevar/rinetd/releases">the rinetd web
+page</a> for the latest release. </p>
+
+<p> Thomas Boutell can be reached by email: <a
+href="mailto:boutell@boutell.com">boutell@boutell.com</a> </p>
+
+<p> Sam Hocevar can be reached by email: <a
+href="mailto:sam@hocevar.net">sam@hocevar.net</a> </p>
+
+<h3>THANKS</h3>
+
+<p> Thanks are due to Bill Davidsen, Libor Pechachek, Sascha Ziemann, Joel
+S. Noble, the Apache Group, and many others who have contributed advice,
+encouragement and/or source code to this and other open software projects. </p>
+
 </body>
 </html>

match.c

@@ -20,7 +20,6 @@ int matchNoCase(char const *sorig, char const *p)
 
 int matchBody(char const *sorig, char const *p, int nocase)
 {
-	static int dummy = 0;
 	/* Algorithm:
 
 		Word separator: *. End-of-string
@@ -56,11 +55,6 @@ int matchBody(char const *sorig, char const *p, int nocase)
 
 	char const *s = sorig;
 	int escaped = 0;
-	if (strstr(p, "WS-0000")) {
-		if (strstr(s, "ws_ftp_pro.html")) {
-			dummy = 1;
-		}
-	}
 	while (1) {
 		char const *word;
 		int wordLen;

parse.peg

@@ -0,0 +1,182 @@
+%{
+#define YY_CTX_LOCAL 1
+#define YY_CTX_MEMBERS \
+    FILE *fp; \
+    int currentLine; \
+    int isAuthAllow; \
+    unsigned int port, bindPort, connectPort; \
+    char *bindAddress, *connectAddress;
+#define YY_INPUT(yyctx, buf, result, max_size) \
+{ \
+    int yyc = fgetc(yyctx->fp); \
+    result = (EOF == yyc) ? 0 : (*(buf) = yyc, 1); \
+}
+#define PARSE_ERROR exit(1);
+%}
+
+file     =  (sol (line eol | invalid_syntax))*
+line     =  -? (rule | auth | logfile | pidlogfile | logcommon )? -? comment?
+
+comment  =  "#" (!eol .)*
+
+rule  =  bind_address - bind_port - connect_address - connect_port {
+	/* Turn all of this stuff into reasonable addresses */
+	struct in_addr iaddr;
+	if (getAddress(yy->bindAddress, &iaddr) < 0) {
+		fprintf(stderr, "rinetd: host %s could not be resolved.\n",
+			yy->bindAddress);
+		PARSE_ERROR;
+	}
+	/* Make a server socket */
+	SOCKET fd = socket(PF_INET, SOCK_STREAM, 0);
+	if (fd == INVALID_SOCKET) {
+		syslog(LOG_ERR, "couldn't create "
+			"server socket! (%m)\n");
+		PARSE_ERROR;
+	}
+	struct sockaddr_in saddr;
+	saddr.sin_family = AF_INET;
+	memcpy(&saddr.sin_addr, &iaddr, sizeof(iaddr));
+	saddr.sin_port = htons(yy->bindPort);
+	int tmp = 1;
+	setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
+		(const char *) &tmp, sizeof(tmp));
+	if (bind(fd, (struct sockaddr *)
+		&saddr, sizeof(saddr)) == SOCKET_ERROR)
+	{
+		/* Warn -- don't exit. */
+		syslog(LOG_ERR, "couldn't bind to "
+			"address %s port %d (%m)\n",
+			yy->bindAddress, yy->bindPort);
+		closesocket(fd);
+		PARSE_ERROR;
+	}
+	if (listen(fd, RINETD_LISTEN_BACKLOG) == SOCKET_ERROR) {
+		/* Warn -- don't exit. */
+		syslog(LOG_ERR, "couldn't listen to "
+			"address %s port %d (%m)\n",
+			yy->bindAddress, yy->bindPort);
+		closesocket(fd);
+		PARSE_ERROR;
+	}
+#if _WIN32
+	u_long ioctltmp;
+#else
+	int ioctltmp;
+#endif
+	ioctlsocket(fd, FIONBIO, &ioctltmp);
+	if (getAddress(yy->connectAddress, &iaddr) < 0) {
+		/* Warn -- don't exit. */
+		syslog(LOG_ERR, "host %s could not be resolved.\n",
+			yy->bindAddress);
+		closesocket(fd);
+		PARSE_ERROR;
+	}
+	/* Allocate server info */
+	seInfo = (ServerInfo *)
+		realloc(seInfo, sizeof(ServerInfo) * (seTotal + 1));
+	if (!seInfo) {
+		PARSE_ERROR;
+	}
+	ServerInfo *srv = &seInfo[seTotal];
+	memset(srv, 0, sizeof(*srv));
+	srv->fd = fd;
+	srv->localAddr = iaddr;
+	srv->localPort = htons(yy->connectPort);
+	srv->fromHost = yy->bindAddress;
+	if (!srv->fromHost) {
+		PARSE_ERROR;
+	}
+	srv->fromPort = yy->bindPort;
+	srv->toHost = yy->connectAddress;
+	if (!srv->toHost) {
+		PARSE_ERROR;
+	}
+	srv->toPort = yy->connectPort;
+#ifndef _WIN32
+	if (fd > maxfd) {
+		maxfd = fd;
+	}
+#endif
+	++seTotal;
+
+	yy->bindAddress = yy->connectAddress = NULL;
+}
+
+bind_address     =  < ipv4 > { yy->bindAddress = strdup(yytext); }
+connect_address  =  < ipv4 > { yy->connectAddress = strdup(yytext); }
+bind_port        =  port { yy->bindPort = yy->port; }
+connect_port     =  port { yy->connectPort = yy->port; }
+
+port  =  < (number | service) > {
+	struct servent *bindService = getservbyname(yytext, "tcp");
+	yy->port = bindService ? ntohs(bindService->s_port) : atoi(yytext);
+	if (yy->port == 0 || yy->port >= 65536) {
+		syslog(LOG_ERR, "bind port missing or out of range\n");
+		PARSE_ERROR;
+	}
+}
+
+auth  =  auth_key - < pattern > {
+	allRules = (Rule *)
+		realloc(allRules, sizeof(Rule) * (allRulesCount + 1));
+	if (!allRules) {
+		PARSE_ERROR;
+	}
+	allRules[allRulesCount].pattern = strdup(yytext);
+	if (!allRules[allRulesCount].pattern) {
+		PARSE_ERROR;
+	}
+	allRules[allRulesCount].type = yy->isAuthAllow ? allowRule : denyRule;
+	if (seTotal > 0) {
+		if (seInfo[seTotal - 1].rulesStart == 0) {
+			seInfo[seTotal - 1].rulesStart = allRulesCount;
+		}
+		++seInfo[seTotal - 1].rulesCount;
+	} else {
+		++globalRulesCount;
+	}
+	++allRulesCount;
+}
+
+auth_key = < ("allow" | "deny") >         { yy->isAuthAllow = (yytext[0] == 'a'); }
+
+logfile  =  "logfile" - < filename > {
+	logFileName = strdup(yytext);
+	if (!logFileName) {
+		PARSE_ERROR;
+	}
+}
+
+pidlogfile  =  "pidlogfile" - < filename > {
+	pidLogFileName = strdup(yytext);
+	if (!pidLogFileName) {
+		PARSE_ERROR;
+	}
+}
+
+logcommon  =  "logcommon" {
+	logFormatCommon = 1;
+}
+
+invalid_syntax  =  < (!eol .)+ > eol {
+	fprintf(stderr, "rinetd: invalid syntax at line %d: %s\n",
+	        yy->currentLine, yytext);
+	PARSE_ERROR; /* FIXME */
+}
+
+service  =  name
+ipv4     =  number [.] number [.] number [.] number | '0'
+pattern  =  [0-9*?]+ ('.' [0-9*?]+ ('.' [0-9*?]+ ('.' [0-9*?]+)?)?)?
+number   =  digit+
+
+name     =  [a-zA-Z][a-zA-Z0-9_]*
+filename =  '"' [^"]+ '"'
+         | [^ \t\r\n]+
+
+-        =  [ \t]+
+digit    =  [0-9]
+sol      =  { ++yy->currentLine; }
+eol      =  '\r'? '\n' | eof
+eof      =  '\0'
+

rinetd.8

@@ -2,7 +2,7 @@
 .\" This software is released for free use under the terms of
 .\" the GNU Public License, version 2 or higher.
 .\"
-.Dd February 18, 1999
+.Dd July 19, 2017
 .Dt RINETD 8
 .Os LINUX
 .Sh NAME
@@ -12,12 +12,12 @@
 .Sh SYNOPSIS
 .Nm /usr/sbin/rinetd
 .Sh VERSION
-Version 0.62, 04/14/2003.
+Version 0.63, 2017/07/19.
 .Sh DESCRIPTION
 .Nm rinetd
 redirects TCP connections from one IP address and port to another. rinetd
 is a single-process server which handles any number of connections to
-the address/port pairs specified in the file /etc/rinetd.conf. 
+the address/port pairs specified in the file /etc/rinetd.conf.
 Since rinetd runs as a single process using nonblocking I/O, it is
 able to redirect a large number of connections without a severe
 impact on the machine. This makes it practical to run TCP services
@@ -29,7 +29,7 @@ rinetd is typically launched at boot time, using the following syntax:
 /usr/sbin/rinetd
 .Pp
 The configuration file is found in the file /etc/rinetd.conf, unless
-another file is specified using the -c command line option. 
+another file is specified using the -c command line option.
 .Sh FORWARDING RULES
 Most entries in the configuration file are forwarding rules. The
 format of a forwarding rule is as follows:
@@ -42,12 +42,12 @@ For example:
 .Pp
 Would redirect all connections to port 80 of the "real" IP address
 206.125.69.81, which could be a virtual interface, through
-rinetd to port 80 of the address 10.1.1.2, which would typically 
+rinetd to port 80 of the address 10.1.1.2, which would typically
 be a machine on the inside of a firewall which has no
 direct routing to the outside world.
 .Pp
 Although responding on individual interfaces rather than on all
-interfaces is one of rinetd's primary features, sometimes it is 
+interfaces is one of rinetd's primary features, sometimes it is
 preferable to respond on all IP addresses that belong to the server.
 In this situation, the special IP address 0.0.0.0
 can be used. For example:
@@ -65,15 +65,15 @@ Both IP addresses and hostnames are accepted for
 bindaddress and connectaddress.
 .Pp
 .Sh ALLOW AND DENY RULES
-Configuration files can also contain allow and deny rules. 
+Configuration files can also contain allow and deny rules.
 .Pp
 Allow rules which appear before the first forwarding rule are
 applied globally: if at least one global allow rule exists,
 and the address of a new connection does not
 satisfy at least one of the global allow rules, that connection
-is immediately rejected, regardless of any other rules. 
+is immediately rejected, regardless of any other rules.
 .Pp
-Allow rules which appear after a specific forwarding rule apply 
+Allow rules which appear after a specific forwarding rule apply
 to that forwarding rule only. If at least one allow rule
 exists for a particular forwarding rule, and the address of a new
 connection does not satisfy at least one of the allow rules
@@ -82,12 +82,12 @@ rejected, regardless of any other rules.
 .Pp
 Deny rules which appear before the first forwarding rule are
 applied globally: if the address of a new connection satisfies
-any of the global allow rules, that connection
-is immediately rejected, regardless of any other rules. 
+any of the global deny rules, that connection
+is immediately rejected, regardless of any other rules.
 .Pp
-Deny rules which appear after a specific forwarding rule apply 
+Deny rules which appear after a specific forwarding rule apply
 to that forwarding rule only. If the address of a new
-connection satisfies any of the deny rules for that forwarding rule, 
+connection satisfies any of the deny rules for that forwarding rule,
 that connection is immediately rejected, regardless of any other rules.
 .Pp
 The format of an allow rule is as follows:
@@ -97,7 +97,7 @@ allow pattern
 Patterns can contain the following characters: 0, 1, 2, 3, 4, 5,
 6, 7, 8, 9, . (period), ?, and *. The ? wildcard matches any one
 character. The * wildcard matches any number of characters, including
-zero. 
+zero.
 .Pp
 For example:
 .Pp
@@ -114,7 +114,7 @@ connections would be forced to pause during the address lookup.
 rinetd is able to produce a log file in either of two formats:
 tab-delimited and web server-style "common log format."
 .Pp
-By default, rinetd does not produce a log file. To activate logging, add 
+By default, rinetd does not produce a log file. To activate logging, add
 the following line to the configuration file:
 .Pp
 logfile log-file-location
@@ -173,20 +173,26 @@ use a single TCP socket. This rules out FTP.
 The server redirected to is not able to identify the host the
 client really came from. This cannot be corrected; however,
 the log produced by rinetd provides a way to obtain this
-information. Under Unix, Sockets would theoretically lose data when closed 
-with SO_LINGER turned off, but in Linux this is not the case (kernel 
-source comments support this belief on my part). On non-Linux Unix platforms, 
+information. Under Unix, Sockets would theoretically lose data when closed
+with SO_LINGER turned off, but in Linux this is not the case (kernel
+source comments support this belief on my part). On non-Linux Unix platforms,
 alternate code which uses a different trick to work around blocking close()
 is provided, but this code is untested. The logging is inadequate.
 The duration of each connection should be logged.
 .Sh LICENSE
 Copyright (c) 1997, 1998, 1999, Thomas Boutell and Boutell.Com, Inc.
+.Pp
+Copyright (c) 2003\-2017 Sam Hocevar
+.Pp
 This software is released for free use under the terms of
 the GNU Public License, version 2 or higher. NO WARRANTY
 IS EXPRESSED OR IMPLIED. USE THIS SOFTWARE AT YOUR OWN RISK.
 .Sh CONTACT INFORMATION
-See http://www.boutell.com/rinetd/ for the latest release.
+See https://github.com/samhocevar/rinetd/releases for the latest release.
+.Pp
 Thomas Boutell can be reached by email: boutell@boutell.com
+.Pp
+Sam Hocevar can be reached by email: sam@hocevar.net
 .Sh THANKS
 Thanks are due to Bill Davidsen, Libor Pechachek, Sascha Ziemann, the
 Apache Group, and many others who have contributed advice

rinetd.conf

@@ -16,7 +16,8 @@
 # to apply to only that forwarding rule
 #
 # bindadress    bindport  connectaddress  connectport
-
+127.0.0.1 4000    127.0.0.1 22
+#127.0.0.1 4000/udp    127.0.0.1 22
 
 # logging information
 logfile /var/log/rinetd.log

rinetd.h

@@ -0,0 +1,69 @@
+/* Constants */
+
+static int const RINETD_BUFFER_SIZE = 16384;
+static int const RINETD_LISTEN_BACKLOG = 128;
+
+#define RINETD_CONFIG_FILE "/etc/rinetd.conf"
+#define RINETD_PID_FILE "/var/run/rinetd.pid"
+
+/* Program state */
+
+enum ruleType {
+	allowRule,
+	denyRule,
+};
+
+typedef struct _rule Rule;
+struct _rule
+{
+	char *pattern;
+	int type;
+};
+
+typedef struct _server_info ServerInfo;
+struct _server_info {
+	SOCKET fd;
+
+	/* In network order, for network purposes */
+	struct in_addr localAddr;
+	unsigned short localPort;
+
+	/* In ASCII and local byte order, for logging purposes */
+	char *fromHost, *toHost;
+	int fromPort, toPort;
+
+	/* Offset and count into list of allow and deny rules. Any rules
+		prior to globalAllowRules and globalDenyRules are global rules. */
+	int rulesStart, rulesCount;
+};
+
+typedef struct _socket Socket;
+struct _socket
+{
+	SOCKET fd;
+	/* recv: received on this socket
+		sent: sent to this socket from the other buffer */
+	int recvPos, sentPos;
+	int recvBytes, sentBytes;
+	char *buffer;
+};
+
+typedef struct _connection_info ConnectionInfo;
+struct _connection_info
+{
+	Socket remote, local;
+	struct in_addr reAddresses;
+	int coClosing;
+	int coLog;
+	ServerInfo const *server; // only useful for logEvent
+};
+
+/* Option parsing */
+
+typedef struct _rinetd_options RinetdOptions;
+struct _rinetd_options
+{
+	char const *conf_file;
+	int foreground;
+};
+