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@@ -0,0 +1,916 @@
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+#if 0 /* -*- mode: c; c-file-style: "gnu"; tab-width: 8; -*-
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+
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+# This program is easy to compile. For example the following ways:
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+# $ sh identd.c
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+# $ sh identd.c -g -DDEBUG
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+# $ sh identd.c -s -DXXXMULTI
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+# $ sh identd.c TRG=fake_identd -s -DBIND_ADDRESS=127.0.0.1
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+# $ sh identd.c CC=cc
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+# $ sh identd.c CC=egcs -s -fomit-frame-pointer
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+
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+set -eu
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+
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+CC= TRG=`basename "$0" .c` OIFS=$IFS
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+for arg in "$@" ''
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+do case $arg in TRG=*) TRG=`echo "$arg" | sed 's/TRG=//'`; shift ;;
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+ CC=*) CC=`echo "$arg" | sed 's/CC=//'`; shift ;;
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+ clean) set -x; exec rm -f "$TRG" ;;
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+ readme) set -x; exec sed -n '1,/[e]nd/d;/\*\//q;s/..//p' "$0";;
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+ '') set 0 -s -O2; shift; break ;;
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+ *) break ;;
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+esac; done
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+case `uname` in SunOS) L='-lsocket -lnsl' ;; *) L= ;; esac
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+
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+WARN="-Wall -Wstrict-prototypes -pedantic -Wno-long-long"
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+WARN="$WARN -Wcast-align -Wpointer-arith " # -Wfloat-equal #-Werror
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+WARN="$WARN -W -Wwrite-strings -Wcast-qual -Wshadow" # -Wconversion
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+
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+VERSION=`sed -n '/^ [*] Version / {
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+ s/.*Version \([^ ]*\) *\([^ ]*\).*./\1 (\2)/p; q; }' "$0"`
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+case $VERSION in '') echo Could not read version information. >&2; exit 1; esac
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+TRGNAME=`basename "$TRG"`
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+set -x; exec ${CC:-gcc} $WARN "$@" -DTRG="\"$TRGNAME\"" \
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+ -DVERSION="\"$VERSION\"" -o "$TRG" "$0" $L
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+exit 1
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+# */
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+#endif
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+/*
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+ * identd.c 2.6 2012-05-31 20:37:27 UTC
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+ *
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+ * Author: Tomi Ollila -- too ät iki fi
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+ *
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+ * Created: Sat Nov 25 15:34:07 EET 1995 too
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+ * Last modified: Thu 31 May 2012 23:37:27 EEST too
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+ *
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+ * This program is standalone 'fake' ident daemon. This program does
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+ * not fork() but is configured to handle up to 20 concurrent connections.
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+ * Since one connection should not last long, if all 20 connections are
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+ * in use, the next connection will close the oldest connection data
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+ * has been read. This way this program is not very vulnerable to so
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+ * called `denial of service' attack, thus making this ideal "identd"
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+ * to be used in a firewall, IP masquerading hosts etc.
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+ *
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+ * Program takes one (or many) arguments, which if exist, determines the
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+ * `user' name(s) that is returned for successful ident query.
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+ *
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+ * This program is free software; you can redistribute it and/or modify
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+ * it under the terms of the GNU General Public License as published by
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+ * the Free Software Foundation; either version 2, or (at your option)
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+ * any later version.
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+ *
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+ * This program is distributed in the hope that it will be useful,
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+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
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+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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+ * GNU General Public License for more details.
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+ *
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+ * HISTORY
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+ *
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+ * Version 2.6 2012-05-31 20:37:27 UTC
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+ * Applied patches from the wl500g project, including IPv6 support, with
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+ * minor tweaks (patches provided by Daniel Gimpelevich. Thanks).
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+ *
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+ * Version 2.5 $Id: identd.c 862 2006-05-18 14:16:34Z too $
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+ * Minor build and readme updates.
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+ *
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+ * Version 2.4 identd.c 568 2005-09-07 20:18:39Z too
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+ * More compilation warnings options set -- iov.base being non-const
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+ * gives warnings that are hard to avoid...
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+ *
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+ * Version 2.3 identd.c 564 2005-09-06 19:15:20Z too
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+ * Randident code from Matthias Jung tuned in.
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+ *
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+ * Version 2.2 identd.c 12 2004-09-08 21:46:54Z too
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+ * Fixed getservbyname() to look port for "auth" instead of "identd"
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+ * port. This "bug" also revealed port number byte order handling bug,
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+ * which was fixed.
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+ * Now this file is stored in subversion repository -- I entered
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+ * $ svn propset svn:keywords Id identd.c -- let's see how it works...
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+ * ... ``svn propset svn:keywords 'Id Rev' identd.c'' !!!
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+ *
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+ * Revision 2.1 2004/01/15 18:14:42 too
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+ * Made BIND_ADDRESS definable (in compiler command line).
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+ * Added some typecasts (using checked_cast() macro).
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+ * Thanks to Jeffrey D. Wheelhouse for his content.
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+ *
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+ * Revision 2.0 2003/05/05 15:21:01 too
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+ * Major update. Removed fdprintf(); replaced with use of
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+ * writev() and newly added outputstrings().
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+ * Removed many now obsolete defines and converted one to
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+ * constant character string.
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+ * Added one assert() (and left room for more). Did some
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+ * relativily small other adjustments.
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+ *
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+ * Revision 1.7 2002/09/29 07:50:20 too
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+ * No longer chops up to IDSTR_MAX chars, but uses "%.*s" to limit length;
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+ * now works also when XXXMULTI defined.
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+ * Back-hacked self-compilable trick, with more tricks to avoid compiler
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+ * warnings.
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+ * Removed own define of FD_SETSIZE altogether;
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+ * systems has it small to begin with.
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+ * Line '415' (or whatever that is now) fixed. () -> (void) in func def.
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+ * Some fine-tuning.
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+ * Thanks to Cristian for his patches.
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+ *
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+ * Revision 1.6.1 2002-09-28 12:30:29 +0200 cii
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+ * + added defines for IDSTR_MAX, IDENT_SUBSTR, IDSTR_BUFLEN and IDSTR_MAX
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+ * (length limit on the id-string)
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+ * + program arg 1 chopped after IDSTR_MAX characters (when applicable);
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+ * reason is:
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+ * - if the program is called with a relativelly long string as arg 1
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+ * (tested with about 400 chars), a segfault occurs due to an internal
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+ * buffer overflow (buffer space reserved for id-string is 128 chars,
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+ * but never verified)
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+ * - it may trigger buffer overflows in clients
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+ * + put a proper comment at the top of the file
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+ * + sorted out FD_SETSIZE (on Linux it's already defined)
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+ * - moved it down below all the includes
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+ * + added time.h include
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+ * + added some short comments
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+ * + conditionals '{', '}' enclosed
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+ * + variable index -> idx in function closeOldest (killed a warning)
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+ * + splitted multiple statements on a singel line
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+ * + splitted long lines
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+ * + prototypes ending in '()' -> '(void)'; changed by protoize
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+ * + corrected most warnings, but "function declaration isn't a prototype"
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+ * which still occurs on line: 415
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+ * + added IDENT_PORT
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+ * + added IDENT_SUBSTR
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+ *
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+ * Revision 1.6 2002/07/31 16:25:20 too
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+ * Now works when started as root (in Linux). Stupid me, tested
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+ * only starting as an ordinary loser.
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+ *
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+ * Revision 1.5 2002/07/29 14:02:42 too
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+ * Added possibility to have multible reply users, one (pseudo)randomly
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+ * chosen at each time.
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+ *
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+ * Revision 1.4 2001/02/09 08:45:42 too
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+ * Now GID is also changed to nobody/nogroup.
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+ *
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+ * Revision 1.3 2000/06/07 05:55:44 too
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+ * Fixed some Solaris compilation "bugs".
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+ * Changed LOG_PERROR to LOG_CONS
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+ *
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+ * Revision 1.2 1999/07/30 04:08:42 too
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+ * Added printing version string (and exit) with `-V' command line option.
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+ *
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+ * Revision 1.1 1999/04/21 17:23:20 too
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+ * - Writes process id to /var/run/identd.pid.
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+ * - Changes (effective) user id to `nobody' after initialization
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+ * (binding socket etc.).
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+ * - Ignores some signals (HUP and PIPE).
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+ * - Handles some signals that aborts by default. The handler function
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+ * tries to get rid of the pidfile.
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+ *
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+ * Revision 0.9b 1999/04/15 20:45:12 too
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+ * Not so much spaghetti anymore. Added documentation and more replies.
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+ *
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+ * Revision 0.9 1999/04/12 18:30:00 too
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+ * Version for unix systems. Standalone, supports 20 concurrent connections.
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+ * The code is quite a spaghetti. But that does not matter.
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+ */
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+
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+#ifdef DEBUG
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+#undef ndebug
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+#else
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+#define ndebug 1
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+#endif
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+
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+#include <assert.h>
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+#include <unistd.h>
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+#include <stdio.h>
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+#include <stdlib.h>
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+#include <stdarg.h>
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+#include <string.h>
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+#include <fcntl.h>
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+#include <signal.h>
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+#include <syslog.h>
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+
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+#include <pwd.h>
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+#include <netdb.h>
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+
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+#include <sys/syslog.h>
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+#include <sys/types.h>
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+#include <sys/time.h>
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+#include <time.h>
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+#include <sys/socket.h>
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+#include <netinet/in.h>
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+#include <errno.h>
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+#include <arpa/inet.h>
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+#include <sys/uio.h>
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+
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+#include <endian.h>
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+
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+#if __BYTE_ORDER == __BIG_ENDIAN
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+
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+#define IPADDR(a,b,c,d) ((in_addr_t)((a << 24) + (b << 16) + (c << 8) + d))
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+#define IPPORT(v) ((in_port_t)v)
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+#define A_x_256(a)((a<<8))
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+
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+#elif __BYTE_ORDER == __LITTLE_ENDIAN
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+
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+#define IPADDR(a,b,c,d) (a + (b << 8) + (c << 16) + (d << 24))
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+#define IPPORT(v) ((in_port_t)((v >> 8) | (v << 8)))
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+#define A_x_256(a) (a)
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+
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+#else
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+#error unknown ENDIAN
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+#endif
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+
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+#ifndef __STRING
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+#define __STRING(x) #x
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+#endif
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+/* Let's see how long-lived this is... */
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+#define __STRINGIFY_MACRO(x) __STRING(x)
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+
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+#ifndef BIND_ADDRESS
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+#define BIND_ADDRESS 0.0.0.0
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+#endif
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+#ifndef BIND_ADDRESS6
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+#define BIND_ADDRESS6 ::
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+#endif
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+#define IDENT_PORT 113
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+#define MAXCONNS 20
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+#define MAXIDLETIME 45
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+
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+#ifndef USE_UNIX_OS
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+static const char ident_substr[] = " : USERID : OTHER : ";
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+#else
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+static const char ident_substr[] = " : USERID : UNIX : ";
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+#endif
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+static const int ident_substr_len = sizeof ident_substr - 1;
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+
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+#if !defined __cplusplus
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+typedef enum { false = 0, true = 1 } bool;
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+#endif
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+
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+#if (__GNUC__ >= 3)
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+#define GCCATTR_UNUSED __attribute ((unused))
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+
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+#define from_type(ft, v) \
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+ __builtin_choose_expr (__builtin_types_compatible_p (typeof (v), ft), \
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+ (v), (void)0)
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+
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+#define checked_cast(ft, tt, v) \
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+ __builtin_choose_expr (__builtin_types_compatible_p (typeof (v), ft), \
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+ ((tt)(v)), (void)0)
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+#else
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+#define GCCATTR_UNUSED
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+
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+#define from_type(ft, v) (v)
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+#define checked_cast(ft, tt, v) ((tt)(v))
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+#endif
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+
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+/* ... */
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+#define CVP (const void *)
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+
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+#ifndef DEBUG
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+#define FCS 2 /* First Connection Socket */
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+#define TRACE(x, y);
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+#else
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+#define FCS 4
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+#define TRACE(x, y) if (x) printf y
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+#endif
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+
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+/* descriptors when debugging:
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+ * 0 = server socket
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+ * 1 = standard output (debugging output)
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+ * 2 = standard error
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+ * 3 = syslog fd (hopefully -- otherwise may work a bit wierdly)
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+ * 4 - 4 + MAXCONNS = connection sockets
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+ *
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+ * descriptors when not debugging
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+ * 0 = server socket
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+ * 1 = syslog fd (hopefully -- otherwise this won't work)
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+ * 2 = connection socket after detached from tty. standard error before that
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+ * 3 - 2 + MAXCONNS = rest connection sockets
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+ *
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+ * To try to make sure that syslog fd is what is "requested", the that fd
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+ * is closed before openlog() call. It can only severely fail if fd 0
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+ * is initially closed.
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+ */
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+
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+/*
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+ * FD of the connection is always the index of the connection structure
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+ * in `conns' array + FCS
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+ */
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+struct {
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+ char buf[20];
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+ int len;
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+ time_t lasttime;
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+} conns[MAXCONNS];
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+
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+
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+/*
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+ * To support multible usernames that can be replied by this fake identd
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+ * define `XXXMULTI' in compilation command line. This doesn't look guite
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+ * pretty, but alternatives looks even uglier.
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+ * XXX NOTE: multi currently only slightly tested XXXX.
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+ */
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+#ifdef XXXMULTI
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+#define IU_IN_STRUCT const char * const * identuserlist; int identusers
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+#define SET_IU(s, c) do { G.identuserlist = &(s); G.identusers = c; } while (0)
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+#define IU_IN_USAGESTR "[identuser [identuser2...]]"
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+#else
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+#define IU_IN_STRUCT const char * identuser
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+#define SET_IU(s, c) G.identuser = (s)
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+#define IU_IN_USAGESTR "[identuser]"
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+#endif
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+
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+/* When using global variables, bind those at least to a structure. */
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+struct {
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+ IU_IN_STRUCT;
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+ fd_set readfds;
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+ int conncnt;
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+ bool randident;
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+} G;
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+
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+/*
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+ * Prototypes
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+ */
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+static void reply(int s, char * buf);
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+static void replyError(int s, const char * buf);
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+static const char * strerrno(void);
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+
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+static const int one = 1;
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+static const char * const nobodystr = "nobody";
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+static const char * alphanum =
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+ "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
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+
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+static inline void movefd(int from, int to)
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+{
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+ TRACE(1, ("movefd(from = %d, to = %d)\n", from, to));
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+ if (from != to)
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+ {
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+ dup2(from, to);
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+ close(from);
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+ }
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+}
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+
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+/*
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+ * inetbind() must always return 0 or value < 0.
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+ * ... i.e. this version -- saves need for storage of the return value.
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+ */
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+
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+#if 0 /* unused */
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+static int inetbind(int port)
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+{
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+ return inetbind(htons(port));
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+}
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+#endif
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+
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+static int inetbind(int ipport)
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+{
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+ int s, len;
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+ union {
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+ struct sockaddr_in sin4;
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+ struct sockaddr_in6 sin6;
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+ } addr;
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+
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+ close(0);
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+ memset(&addr, 0, sizeof addr);
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+
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+ if ((s = socket(AF_INET6, SOCK_STREAM, 0)) >= 0)
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+ {
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+ len = sizeof addr.sin6;
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+ inet_pton(AF_INET6, __STRINGIFY_MACRO(BIND_ADDRESS6), &addr.sin6.sin6_addr);
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+ addr.sin6.sin6_family = AF_INET6;
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+ addr.sin6.sin6_port = ipport;
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+ }
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+ else
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|
|
+ if ((s = socket(AF_INET, SOCK_STREAM, 0)) >= 0)
|
|
|
+ {
|
|
|
+ len = sizeof addr.sin4;
|
|
|
+ addr.sin4.sin_addr.s_addr = inet_addr(__STRINGIFY_MACRO(BIND_ADDRESS));
|
|
|
+ addr.sin4.sin_family = AF_INET;
|
|
|
+ addr.sin4.sin_port = ipport;
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ syslog(LOG_CRIT, "Can not create server socket: %s.", strerrno());
|
|
|
+ return -1;
|
|
|
+ }
|
|
|
+
|
|
|
+ setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one);
|
|
|
+
|
|
|
+ if (bind(s, (struct sockaddr *)&addr, len) < 0)
|
|
|
+ {
|
|
|
+ syslog(LOG_CRIT, "Can not bind() server socket: %s.", strerrno());
|
|
|
+ return -1;
|
|
|
+ }
|
|
|
+
|
|
|
+ if (listen(s, 5) < 0)
|
|
|
+ {
|
|
|
+ syslog(LOG_CRIT, "Can not listen() server socket: %s.", strerrno());
|
|
|
+ return -1;
|
|
|
+ }
|
|
|
+
|
|
|
+ movefd(s, 0);
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+static void deleteConn(int s)
|
|
|
+{
|
|
|
+ int i = s - FCS;
|
|
|
+
|
|
|
+ TRACE(1, ("deleteConn(): socket %d, conncnt %d\n", s, G.conncnt));
|
|
|
+
|
|
|
+ close(s);
|
|
|
+
|
|
|
+ G.conncnt--;
|
|
|
+
|
|
|
+ /*
|
|
|
+ * Most of the time there is 0 connections. Most often that there
|
|
|
+ * is connections, there is just one connection. When this one connection
|
|
|
+ * closes, i == G.conncnt = 0 -> no copying.
|
|
|
+ * When there is more than one connection, the oldest connections closes
|
|
|
+ * earlier on average. When this happens, the code below starts copying
|
|
|
+ * the connection structure w/ highest index to the place which which is
|
|
|
+ * just deleted. This means that the connection structures are no longer
|
|
|
+ * in chronological order. I'd quess this means that when there is more
|
|
|
+ * than 1 connection, on average every other connection structure needs
|
|
|
+ * to be copied over the time all these connections are deleted.
|
|
|
+ */
|
|
|
+ if (i != G.conncnt)
|
|
|
+ {
|
|
|
+ memcpy(&conns[i], &conns[G.conncnt], sizeof conns[0]);
|
|
|
+ movefd(G.conncnt + FCS, s);
|
|
|
+ }
|
|
|
+
|
|
|
+ TRACE(1, ("Clearing fd %d, readfds now 0x%x\n\n",
|
|
|
+ G.conncnt + FCS, *(int *)&G.readfds));
|
|
|
+
|
|
|
+ FD_CLR(G.conncnt + FCS, &G.readfds);
|
|
|
+}
|
|
|
+
|
|
|
+static int closeOldest(void)
|
|
|
+{
|
|
|
+ time_t min = conns[0].lasttime;
|
|
|
+ int idx = 0;
|
|
|
+ int i;
|
|
|
+
|
|
|
+ for (i = 1; i < MAXCONNS; i++)
|
|
|
+ if (conns[i].lasttime < min)
|
|
|
+ idx = i;
|
|
|
+
|
|
|
+ TRACE(1, ("closeOldest(): index %d, socket %d\n", idx, idx + FCS));
|
|
|
+
|
|
|
+ replyError(idx + FCS, "X-SERVER-TOO-BUSY");
|
|
|
+ close(idx + FCS);
|
|
|
+
|
|
|
+ return idx;
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+static int checkInput(char * buf, int len, int l)
|
|
|
+{
|
|
|
+ int i;
|
|
|
+
|
|
|
+ for (i = len; i < len + l; i++)
|
|
|
+ if (buf[i] == '\n')
|
|
|
+ return 1;
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+static int getport(void)
|
|
|
+{
|
|
|
+ struct servent * se;
|
|
|
+
|
|
|
+ if ((se = getservbyname("auth", "tcp")) == NULL)
|
|
|
+ return IPPORT(IDENT_PORT);
|
|
|
+ else
|
|
|
+ return se->s_port;
|
|
|
+}
|
|
|
+
|
|
|
+static const char * strerrno()
|
|
|
+{
|
|
|
+#if 1
|
|
|
+ return strerror(errno);
|
|
|
+#else
|
|
|
+ extern char * sys_errlist[];
|
|
|
+ return sys_errlist[errno];
|
|
|
+#endif
|
|
|
+}
|
|
|
+
|
|
|
+#define WriteCS(f, s) write(f, s, sizeof s - 1)
|
|
|
+
|
|
|
+static void writestrings(int fd, const char * str, ...)
|
|
|
+{
|
|
|
+ va_list ap;
|
|
|
+
|
|
|
+ va_start(ap, str);
|
|
|
+
|
|
|
+ while (str)
|
|
|
+ {
|
|
|
+ write(fd, str, strlen(str));
|
|
|
+ str = va_arg(ap, const char *);
|
|
|
+ }
|
|
|
+ va_end(ap);
|
|
|
+}
|
|
|
+
|
|
|
+#ifndef DEBUG
|
|
|
+static void godaemon(void)
|
|
|
+{
|
|
|
+ switch(fork())
|
|
|
+ {
|
|
|
+ case -1: exit(-1);
|
|
|
+ case 0: close(1); close(2); setsid(); break;
|
|
|
+ default: exit(0);
|
|
|
+ }
|
|
|
+}
|
|
|
+#endif
|
|
|
+
|
|
|
+#ifdef TRG
|
|
|
+#define PIDFILE "/var/run/" TRG ".pid"
|
|
|
+#else
|
|
|
+#define PIDFILE "/var/run/identd.pid"
|
|
|
+#endif
|
|
|
+
|
|
|
+static void delpidfile(void)
|
|
|
+{
|
|
|
+ /*
|
|
|
+ * Usually nobody has no write/delete access to directory /var/run/
|
|
|
+ * therefore if file cannot be deleted, it is truncated
|
|
|
+ */
|
|
|
+ if (unlink(PIDFILE) < 0)
|
|
|
+ close(open(PIDFILE, O_WRONLY|O_CREAT|O_TRUNC, 0644));
|
|
|
+}
|
|
|
+
|
|
|
+static void handlexitsigs(void)
|
|
|
+{
|
|
|
+ delpidfile();
|
|
|
+ exit(0);
|
|
|
+}
|
|
|
+
|
|
|
+static void writepid(uid_t nobody, uid_t nogrp)
|
|
|
+ /* May succeed. If not, won't care. */
|
|
|
+{
|
|
|
+ int fd = open(PIDFILE, O_WRONLY|O_CREAT|O_TRUNC, 0664);
|
|
|
+ char buf[24];
|
|
|
+
|
|
|
+ if (fd < 0)
|
|
|
+ return;
|
|
|
+
|
|
|
+ /* we don't use snprintf() here since it is not so portable...*/
|
|
|
+ /* Anyway, 64-bit integer is at max 20 characters long. */
|
|
|
+ sprintf(buf, "%d\n", getpid());
|
|
|
+ buf[23] = '\0';
|
|
|
+ write(fd, buf, strlen(buf));
|
|
|
+ fchown(fd, nobody, nogrp);
|
|
|
+ close(fd);
|
|
|
+
|
|
|
+ signal(SIGTERM, (void(*)(int))handlexitsigs);
|
|
|
+ signal(SIGINT, (void(*)(int))handlexitsigs);
|
|
|
+ signal(SIGQUIT, (void(*)(int))handlexitsigs);
|
|
|
+ /* should this handle ILL, ... (see signal(7)) */
|
|
|
+}
|
|
|
+
|
|
|
+static void printversion(void)
|
|
|
+{
|
|
|
+ struct iovec iv[4];
|
|
|
+
|
|
|
+ iv[0].iov_base = TRG;
|
|
|
+ iv[0].iov_len = sizeof TRG - 1;
|
|
|
+
|
|
|
+ iv[1].iov_base = " ";
|
|
|
+ iv[1].iov_len = 1;
|
|
|
+
|
|
|
+ iv[2].iov_base = VERSION;
|
|
|
+ iv[2].iov_len = sizeof VERSION - 1;
|
|
|
+
|
|
|
+ iv[3].iov_base = ".\n";
|
|
|
+ iv[3].iov_len = 2;
|
|
|
+
|
|
|
+ writev(1, iv, 4);
|
|
|
+}
|
|
|
+
|
|
|
+int main(int argc GCCATTR_UNUSED, const char * argv[])
|
|
|
+{
|
|
|
+ uid_t nobody, nogrp;
|
|
|
+
|
|
|
+ memset(conns, 0, sizeof conns);
|
|
|
+ memset(&G, 0, sizeof G);
|
|
|
+ FD_ZERO(&G.readfds);
|
|
|
+ FD_SET(0, &G.readfds);
|
|
|
+
|
|
|
+ TRACE(1, ("s: `%s', l = %d\n", ident_substr, ident_substr_len));
|
|
|
+
|
|
|
+ if (argv[1])
|
|
|
+ if (argv[1][0] == '-') {
|
|
|
+ if (argv[1][1] == 'V')
|
|
|
+ {
|
|
|
+ printversion();
|
|
|
+ return 0;
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ if (argv[1][1] == 'r')
|
|
|
+ {
|
|
|
+ G.randident = true;
|
|
|
+ srand(time(0));
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ char b[2]; b[0] = argv[1][1]; b[1]= '\0';
|
|
|
+
|
|
|
+ writestrings(2, argv[0], ": invalid option -- ", b, ".\n",
|
|
|
+ "Usage: ", argv[0], " [-rV] ", IU_IN_USAGESTR "\n",
|
|
|
+ NULL);
|
|
|
+ return 1;
|
|
|
+ }
|
|
|
+ }}
|
|
|
+ else
|
|
|
+ SET_IU(argv[1], argc - 1);
|
|
|
+ else
|
|
|
+ SET_IU(nobodystr, 1);
|
|
|
+
|
|
|
+
|
|
|
+#ifndef DEBUG
|
|
|
+ close(1); /* not debugging, openlog() hopefully uses fd 1. */
|
|
|
+#else
|
|
|
+ close(3); /* debugging, TRACE uses fd 1, openlog() hopefully fd 3 */
|
|
|
+#endif
|
|
|
+
|
|
|
+ openlog("identd", LOG_CONS, LOG_DAEMON);
|
|
|
+
|
|
|
+ {
|
|
|
+ struct passwd * pw = getpwnam(nobodystr);
|
|
|
+
|
|
|
+ if (pw)
|
|
|
+ {
|
|
|
+ nobody = pw->pw_uid;
|
|
|
+ nogrp = pw->pw_gid;
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ syslog(LOG_CRIT, "Can not find user `nobody': %s,", strerrno());
|
|
|
+ return -1;
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ if (inetbind(getport()) < 0)
|
|
|
+ return -1;
|
|
|
+
|
|
|
+ /* */
|
|
|
+ {
|
|
|
+ int i;
|
|
|
+
|
|
|
+ for (i = FCS; i < MAXCONNS + FCS; i++)
|
|
|
+ close(i);
|
|
|
+ }
|
|
|
+
|
|
|
+#ifdef DEBUG
|
|
|
+#ifndef LOG_PERROR
|
|
|
+#define LOG_PERROR 0
|
|
|
+#endif
|
|
|
+ openlog("identd", LOG_PERROR, LOG_DAEMON);
|
|
|
+#else /* not DEBUG */
|
|
|
+ godaemon();
|
|
|
+ openlog("identd", 0, LOG_DAEMON);
|
|
|
+ close(2);
|
|
|
+ signal(SIGHUP, SIG_IGN);
|
|
|
+#endif /* DEBUG */
|
|
|
+
|
|
|
+ signal(SIGPIPE, SIG_IGN); /* connection closed when writing (raises ???) */
|
|
|
+
|
|
|
+ writepid(nobody, nogrp);
|
|
|
+
|
|
|
+ setegid(nogrp); setgid(nogrp); setuid(nobody); seteuid(nobody);
|
|
|
+
|
|
|
+ {
|
|
|
+ int i;
|
|
|
+
|
|
|
+ for (i = 0; i < 4; i++)
|
|
|
+ {
|
|
|
+ const char * id = NULL;
|
|
|
+ unsigned int rv = 0;
|
|
|
+
|
|
|
+ switch (i)
|
|
|
+ {
|
|
|
+ case 0: rv = (unsigned int)getegid(); id = "egid"; break;
|
|
|
+ case 1: rv = (unsigned int)getgid(); id = "gid"; break;
|
|
|
+ case 2: rv = (unsigned int)geteuid(); id = "euid"; break;
|
|
|
+ case 3: rv = (unsigned int)getuid(); id = "uid"; break;
|
|
|
+ }
|
|
|
+
|
|
|
+ if (rv == 0)
|
|
|
+ {
|
|
|
+ syslog(LOG_ERR,
|
|
|
+ "Can not drop all root privileges (%s) !!! %s !!!",
|
|
|
+ id, strerrno());
|
|
|
+ delpidfile();
|
|
|
+ return -1;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ while (2)
|
|
|
+ {
|
|
|
+ fd_set rfds = G.readfds;
|
|
|
+ struct timeval tv = { 15, 0 };
|
|
|
+ int i;
|
|
|
+ int tim = time(NULL);
|
|
|
+
|
|
|
+ TRACE(1, ("calling select(): n = %d, rfds = 0x%x\n\n",
|
|
|
+ G.conncnt + FCS, *(int *)&rfds));
|
|
|
+
|
|
|
+ select(G.conncnt + FCS, &rfds, NULL, NULL, G.conncnt? &tv: NULL);
|
|
|
+
|
|
|
+ for (i = G.conncnt - 1; i >= 0; i--)
|
|
|
+ {
|
|
|
+ int s = i + FCS;
|
|
|
+
|
|
|
+ if (FD_ISSET(s, &rfds))
|
|
|
+ {
|
|
|
+ char * buf = conns[i].buf;
|
|
|
+ unsigned int len = conns[i].len;
|
|
|
+ unsigned int l;
|
|
|
+
|
|
|
+ TRACE(1, ("data socket fd_isset %d\n", s));
|
|
|
+
|
|
|
+ if ((int)(l = read(s, buf + len, sizeof conns[0].buf - len)) > 0)
|
|
|
+ {
|
|
|
+ if (checkInput(buf, len, l))
|
|
|
+ {
|
|
|
+ reply(s, buf);
|
|
|
+ goto deleteconn;
|
|
|
+ }
|
|
|
+ else if (len + l >= sizeof conns[0].buf)
|
|
|
+ {
|
|
|
+ replyError(s, "X-INVALID-REQUEST");
|
|
|
+ goto deleteconn;
|
|
|
+ }
|
|
|
+ else
|
|
|
+ conns[i].len += l;
|
|
|
+ }
|
|
|
+ else
|
|
|
+ goto deleteconn;
|
|
|
+
|
|
|
+ conns[i].lasttime = tim;
|
|
|
+ continue;
|
|
|
+
|
|
|
+ deleteconn:
|
|
|
+ deleteConn(s);
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ /* implement as time_after() in linux kernel sources ... */
|
|
|
+ if (conns[i].lasttime + MAXIDLETIME <= tim)
|
|
|
+ {
|
|
|
+ replyError(s, "X-TIMEOUT");
|
|
|
+ deleteConn(s);
|
|
|
+ }
|
|
|
+ }
|
|
|
+ }
|
|
|
+
|
|
|
+ if (FD_ISSET(0, &rfds))
|
|
|
+ {
|
|
|
+ int s = accept(0, NULL, 0);
|
|
|
+
|
|
|
+ TRACE(1, ("server socket fd_isset, %d accepted\n", s));
|
|
|
+
|
|
|
+ if (s < 0)
|
|
|
+ {
|
|
|
+ if (errno != EINTR) /* EINTR */
|
|
|
+ syslog(LOG_ERR, "accept: %s", strerrno());
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ if (G.conncnt == MAXCONNS)
|
|
|
+ i = closeOldest();
|
|
|
+ else
|
|
|
+ i = G.conncnt++;
|
|
|
+
|
|
|
+ movefd(s, i + FCS); /* move if not already there */
|
|
|
+
|
|
|
+ FD_SET(i + FCS, &G.readfds);
|
|
|
+
|
|
|
+ conns[i].len = 0;
|
|
|
+ conns[i].lasttime = time(NULL);
|
|
|
+ }
|
|
|
+ }
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+static int parseAddrs(char * ptr, char ** myaddr, char ** heraddr);
|
|
|
+
|
|
|
+static void replyError(int s, const char * buf)
|
|
|
+{
|
|
|
+ struct iovec iv[3];
|
|
|
+
|
|
|
+ iv[0].iov_base = "0, 0 : ERROR : "; iv[0].iov_len = 15;
|
|
|
+ iv[1].iov_base = buf; iv[1].iov_len = strlen(buf);
|
|
|
+ iv[2].iov_base = "\r\n"; iv[2].iov_len = 2;
|
|
|
+
|
|
|
+ writev(s, iv, 3);
|
|
|
+}
|
|
|
+
|
|
|
+static void reply(int s, char * buf)
|
|
|
+{
|
|
|
+ char * myaddr, *heraddr;
|
|
|
+
|
|
|
+ myaddr = heraddr = NULL;
|
|
|
+
|
|
|
+ if (parseAddrs(buf, &myaddr, &heraddr))
|
|
|
+ replyError(s, "X-INVALID-REQUEST");
|
|
|
+ else
|
|
|
+ {
|
|
|
+ struct iovec iv[6];
|
|
|
+#ifdef XXXMULTI
|
|
|
+ const char * iul = G.identuserlist[random() % G.identusers];
|
|
|
+#endif
|
|
|
+
|
|
|
+ iv[0].iov_base = myaddr; iv[0].iov_len = strlen(myaddr);
|
|
|
+ iv[1].iov_base = ", "; iv[1].iov_len = 2;
|
|
|
+ iv[2].iov_base = heraddr; iv[2].iov_len = strlen(heraddr);
|
|
|
+ iv[3].iov_base = checked_cast(const char[], void *, ident_substr);
|
|
|
+ iv[3].iov_len = ident_substr_len;
|
|
|
+#ifdef XXXMULTI
|
|
|
+ iv[4].iov_base = checked_cast(const char *, void *, iul);
|
|
|
+ iv[4].iov_len = strlen(iul);
|
|
|
+#else
|
|
|
+ if (G.randident)
|
|
|
+ {
|
|
|
+ /* generate random string as reply: */
|
|
|
+ int i;
|
|
|
+ char randomstring[8];
|
|
|
+ int randlen = (random() % 6) + 3; /* random string length 3-8 */
|
|
|
+
|
|
|
+ /* have first char letter... */
|
|
|
+ randomstring[0] = alphanum[10 + random() % 52];
|
|
|
+
|
|
|
+ for (i = 1; i < randlen; i++)
|
|
|
+ randomstring[i] = alphanum[random() % 62];
|
|
|
+
|
|
|
+ iv[4].iov_base = checked_cast(char [], void *, randomstring);
|
|
|
+ iv[4].iov_len = randlen;
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ /* use usual behaviour */
|
|
|
+ iv[4].iov_base = checked_cast(const char *, void *, G.identuser);
|
|
|
+ iv[4].iov_len = strlen(G.identuser);
|
|
|
+ }
|
|
|
+#endif
|
|
|
+ iv[5].iov_base = "\r\n"; iv[5].iov_len = 2;
|
|
|
+
|
|
|
+ writev(s, iv, 6);
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+static int chmatch(char c, const char * chars)
|
|
|
+{
|
|
|
+ for (; *chars; chars++)
|
|
|
+ if (c == *chars)
|
|
|
+ return 1;
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+static int skipchars(char ** p, const char * chars)
|
|
|
+{
|
|
|
+ while (chmatch(**p, chars))
|
|
|
+ (*p)++;
|
|
|
+
|
|
|
+ if (**p == '\r' || **p == '\n')
|
|
|
+ return 0;
|
|
|
+
|
|
|
+ return 1;
|
|
|
+}
|
|
|
+
|
|
|
+static int parseAddrs(char * ptr, char ** myaddr, char ** heraddr)
|
|
|
+{
|
|
|
+ /* parse <port-on-server> , <port-on-client> */
|
|
|
+
|
|
|
+ if (! skipchars(&ptr, " \t"))
|
|
|
+ return -1;
|
|
|
+
|
|
|
+ *myaddr = ptr;
|
|
|
+
|
|
|
+ if (! skipchars(&ptr, "1234567890"))
|
|
|
+ return -1;
|
|
|
+
|
|
|
+ if (! chmatch(*ptr, " \t,"))
|
|
|
+ return -1;
|
|
|
+
|
|
|
+ *ptr++ = '\0';
|
|
|
+
|
|
|
+ if (! skipchars(&ptr, " \t,") )
|
|
|
+ return -1;
|
|
|
+
|
|
|
+ *heraddr = ptr;
|
|
|
+
|
|
|
+ skipchars(&ptr, "1234567890");
|
|
|
+
|
|
|
+ if (! chmatch(*ptr, " \n\r"))
|
|
|
+ return -1;
|
|
|
+
|
|
|
+ *ptr = '\0';
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+/* EOF */
|