support for 6pack tnc rings (patch found at sf.net)

	from Iñaki Arenaza EB2EBU <iarenaza@escomposlinux.org>

4 files changed, 1127 insertions, 0 deletions

diff --git a/6pack/Makefile.am b/6pack/Makefile.am
new file mode 100644
index 0000000..e9673a1
--- /dev/null
+++ b/6pack/Makefile.am
@@ -0,0 +1,20 @@
+
+installconf:
+
+sbin_PROGRAMS = m6pack
+
+LDADD= $(AX25_LIB)
+
+man_MANS = m6pack.8
+
+EXTRA_DIST = $(man_MANS)
+
+INCLUDES = -DAX25_SYSCONFDIR=\""$(AX25_SYSCONFDIR)"\" \
+	   -DAX25_LOCALSTATEDIR=\""$(AX25_LOCALSTATEDIR)"\" 
+
+AX25_SYSCONFDIR=${sysconfdir}/ax25/
+AX25_LOCALSTATEDIR=${localstatedir}/ax25/
+
+install-exec-local:
+	(cd $(DESTDIR)$(sbindir))
+
diff --git a/6pack/Makefile.in b/6pack/Makefile.in
new file mode 100644
index 0000000..17e26ed
--- /dev/null
+++ b/6pack/Makefile.in
@@ -0,0 +1,387 @@
+# Makefile.in generated automatically by automake 1.4-p6 from Makefile.am
+
+# Copyright (C) 1994, 1995-8, 1999, 2001 Free Software Foundation, Inc.
+# This Makefile.in is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY, to the extent permitted by law; without
+# even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+# PARTICULAR PURPOSE.
+
+
+SHELL = @SHELL@
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+VPATH = @srcdir@
+prefix = @prefix@
+exec_prefix = @exec_prefix@
+
+bindir = @bindir@
+sbindir = @sbindir@
+libexecdir = @libexecdir@
+datadir = @datadir@
+sysconfdir = @sysconfdir@
+sharedstatedir = @sharedstatedir@
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+oldincludedir = /usr/include
+
+DESTDIR =
+
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+pkgincludedir = $(includedir)/@PACKAGE@
+
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+
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+AX25IO_LIB = @AX25IO_LIB@
+AX25_LIB = @AX25_LIB@
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+CXX = @CXX@
+FLTK_LIB = @FLTK_LIB@
+HAVE_LIB = @HAVE_LIB@
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+UTIL_LIB = @UTIL_LIB@
+VERSION = @VERSION@
+Z_LIB = @Z_LIB@
+
+sbin_PROGRAMS = m6pack
+
+LDADD = $(AX25_LIB)
+
+man_MANS = m6pack.8
+
+EXTRA_DIST = $(man_MANS)
+
+INCLUDES = -DAX25_SYSCONFDIR=\""$(AX25_SYSCONFDIR)"\" 	   -DAX25_LOCALSTATEDIR=\""$(AX25_LOCALSTATEDIR)"\" 
+
+
+AX25_SYSCONFDIR = ${sysconfdir}/ax25/
+AX25_LOCALSTATEDIR = ${localstatedir}/ax25/
+mkinstalldirs = $(SHELL) $(top_srcdir)/mkinstalldirs
+CONFIG_HEADER = ../config.h
+CONFIG_CLEAN_FILES = 
+PROGRAMS =  $(sbin_PROGRAMS)
+
+
+DEFS = @DEFS@ -I. -I$(srcdir) -I..
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+X_LIBS = @X_LIBS@
+X_EXTRA_LIBS = @X_EXTRA_LIBS@
+X_PRE_LIBS = @X_PRE_LIBS@
+m6pack_SOURCES = m6pack.c
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+TAR = tar
+GZIP_ENV = --best
+DEP_FILES =  .deps/m6pack.P
+SOURCES = m6pack.c
+OBJECTS = m6pack.o
+
+all: all-redirect
+.SUFFIXES:
+.SUFFIXES: .S .c .o .s
+$(srcdir)/Makefile.in: Makefile.am $(top_srcdir)/configure.in $(ACLOCAL_M4) 
+	cd $(top_srcdir) && $(AUTOMAKE) --gnu 6pack/Makefile
+
+Makefile: $(srcdir)/Makefile.in  $(top_builddir)/config.status $(BUILT_SOURCES)
+	cd $(top_builddir) \
+	  && CONFIG_FILES=$(subdir)/$@ CONFIG_HEADERS= $(SHELL) ./config.status
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+	done
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+m6pack: $(m6pack_OBJECTS) $(m6pack_DEPENDENCIES)
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+	$(mkinstalldirs) $(DESTDIR)$(man8dir)
+	@list='$(man8_MANS)'; \
+	l2='$(man_MANS)'; for i in $$l2; do \
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+	    *.8*) list="$$list $$i" ;; \
+	  esac; \
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+	  $(INSTALL_DATA) $$file $(DESTDIR)$(man8dir)/$$inst; \
+	done
+
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+	@list='$(man8_MANS)'; \
+	l2='$(man_MANS)'; for i in $$l2; do \
+	  case "$$i" in \
+	    *.8*) list="$$list $$i" ;; \
+	  esac; \
+	done; \
+	for i in $$list; do \
+	  ext=`echo $$i | sed -e 's/^.*\\.//'`; \
+	  inst=`echo $$i | sed -e 's/\\.[0-9a-z]*$$//'`; \
+	  inst=`echo $$inst | sed '$(transform)'`.$$ext; \
+	  echo " rm -f $(DESTDIR)$(man8dir)/$$inst"; \
+	  rm -f $(DESTDIR)$(man8dir)/$$inst; \
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+
+ID: $(HEADERS) $(SOURCES) $(LISP)
+	list='$(SOURCES) $(HEADERS)'; \
+	unique=`for i in $$list; do echo $$i; done | \
+	  awk '    { files[$$0] = 1; } \
+	       END { for (i in files) print i; }'`; \
+	here=`pwd` && cd $(srcdir) \
+	  && mkid -f$$here/ID $$unique $(LISP)
+
+TAGS:  $(HEADERS) $(SOURCES)  $(TAGS_DEPENDENCIES) $(LISP)
+	tags=; \
+	here=`pwd`; \
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+	  awk '    { files[$$0] = 1; } \
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+	top_distdir=`cd $(top_distdir) && pwd`; \
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+	cd $(top_srcdir) \
+	  && $(AUTOMAKE) --include-deps --build-dir=$$here --srcdir-name=$(top_srcdir) --output-dir=$$top_distdir --gnu 6pack/Makefile
+	@for file in $(DISTFILES); do \
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+	  if test -d $$d/$$file; then \
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+	  | sed -e 's/^\\$$//' -e '/^$$/ d' -e '/:$$/ d' -e 's/$$/ :/' \
+	    >> .deps/$(*F).P; \
+	rm .deps/$(*F).pp
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+%.lo: %.c
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+	$(LTCOMPILE) -Wp,-MD,.deps/$(*F).pp -c $<
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+	  | sed -e 's/^\\$$//' -e '/^$$/ d' -e '/:$$/ d' -e 's/$$/ :/' \
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+	@echo "it deletes files that may require special tools to rebuild."
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+installconf:
+
+install-exec-local:
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+# Tell versions [3.59,3.63) of GNU make to not export all variables.
+# Otherwise a system limit (for SysV at least) may be exceeded.
+.NOEXPORT:
diff --git a/6pack/m6pack.8 b/6pack/m6pack.8
new file mode 100644
index 0000000..831942c
--- /dev/null
+++ b/6pack/m6pack.8
@@ -0,0 +1,54 @@
+.TH M6PACK 8 "28 April 2002" Linux "Linux System Managers Manual"
+.SH NAME
+m6pack \- Attach multiples 6PACK interfaces
+.SH SYNOPSIS
+.B m6pack [-l] [-s speed] [-v] ttyinterface pty1 pty2...
+.SH DESCRIPTION
+.LP
+.B m6pack
+allows multiple 6PACK TNCs sharing the same serial port to be
+used with the Linux AX.25 kernel software. The AX.25 softare has no support
+for multiple TNCs sharing the same serial line. The
+different ports are addressed by encoding the port number in the control
+byte of every 6pack frame.
+.B m6pack
+watches a serial port, and routes 6pack frames to/from the pseudo ttys. The
+other side of the pseudo ttys are then attached with
+.B spattach
+as normal.
+.sp 1
+Statistics about the operation of
+.B m6pack
+may be obtained by sending the SIGUSR1 signal to the running program. On
+reception of such a signal
+.B m6pack
+will print a set of statistics to the system log if logging has been
+enabled.
+.sp 1
+Although mention is made of using pseudo ttys as the last arguments,
+these devices may be normal serial ports. However
+.B m6pack
+provides no way in which to set their speed, the speed must therefore be set
+by some other method.
+.SH OPTIONS
+.TP 10
+.BI \-l
+Enables system logging, the default is off.
+.TP 10
+.BI "\-s speed"
+Set the speed of the serial port.
+.TP 10
+.BI \-v
+Display the version.
+.SH "SEE ALSO"
+.BR spattach (8),
+.BR ifconfig (8),
+.BR kill (1).
+.SH AUTHORS
+Iñaki Arenaza EB2EBU <iarenaza@escomposlinux.org>, based in the work by:
+.br
+Tomi Manninen OH2BNS <tpmannin@cc.hut.fi>
+.br
+Jonathan Naylor G4KLX <g4klx@g4klx.demon.co.uk>
+.br
+Kevin Uhlir N0BEL <kevinu@flochart.com>
diff --git a/6pack/m6pack.c b/6pack/m6pack.c
new file mode 100644
index 0000000..65f85c4
--- /dev/null
+++ b/6pack/m6pack.c
@@ -0,0 +1,666 @@
+/* Hey Emacs! this is -*- linux-c -*- 
+ * from /usr/src/linux/Documentation/CodingStyle
+ *
+ * m6pack.c
+ *
+ * Fake out AX.25 code into supporting 6pack TNC rings by routing serial
+ * port data to/from pseudo ttys.
+ *
+ * @(#)m6pack.c  $Revision: 1.1 $  $Date: 2005/12/10 16:17:28 $
+ *
+ * Author(s):
+ *
+ *	Iñaki Arenaza (EB2EBU) <iarenaza@escomposlinux.org>
+ *
+ * History:
+ *
+ * $Log: m6pack.c,v $
+ * Revision 1.1  2005/12/10 16:17:28  dl9sau
+ *         support for 6pack tnc rings (patch found at sf.net)
+ * 	from Iñaki Arenaza EB2EBU <iarenaza@escomposlinux.org>
+ *
+ * Revision 0.9  2002/04/28 15:05:39  hermes-team
+ * Minor fixes to make it part of ax25-tools-0.0.8
+ *
+ * Revision 0.7  1999/04/25 11:03:51  hermes-team
+ * Minor cosmetic changes.
+ *
+ * Revision 0.6  1999/04/25 10:30:51  hermes-team
+ * TTY unlocking was missing from SIGTERM handler. Thanks to Tommi Manninen
+ * for pointing it out.
+ *
+ * Revision 0.5  1999/04/07 09:16:06  hermes-team
+ * First public beta release. It _seems_ to work with two TNC's in a ring 
+ * (I only have two TNC's to test :-(
+ *
+ * Revision 0.4  1999/04/06 14:35:56  hermes-team
+ * Removed the code that checked that trailing SEOF's address was equal to
+ * leading SEOF's address (it seems this hasn't to be so, but it wasn't very
+ * clear in DG2FEF & HB9JNX's paper)
+ *
+ * Revision 0.3  1999/01/31 23:02:09  hermes-team
+ * Modified code that calls write(2) in sixpack_tx to handle big data blocks.
+ *
+ * Revision 0.2  1999/01/31 15:56:51  hermes-team
+ * Initial Release. This is still alpha software.
+ *
+ *********************************************************************
+ *
+ * Quite a lot of stuff "stolen" from mkiss.c, written by
+ *
+ * 		Kevin Uhlir
+ * 		Ron Curry
+ *		Jonathan Naylor
+ *		Tomi Manninen
+ *
+ * Copyright (C) 1999 Iñaki Arenaza
+ * mkiss.c was GPLed, so I guess this one is GPLed too ;-)
+ *
+ *********************************************************************
+ *
+ * REMARK:
+ *
+ * See document '6pack.ps' by Matthias Welwarsky (DG2FEF), translated
+ * by Thomas Sailer (HB9JNX) found in ax25-doc-1.0.tgz for details about
+ * 6pack protocol specifications.
+ *
+ *********************************************************************
+ */
+
+#include <stdio.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <time.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <termios.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <ctype.h>
+#include <syslog.h>
+
+#include <netax25/ttyutils.h>
+#include <netax25/daemon.h>
+
+#include <config.h>
+
+static char *version ="$Id: m6pack.c,v 1.1 2005/12/10 16:17:28 dl9sau Exp $";
+
+typedef unsigned char __u8;
+typedef enum {data, command} frame_t;
+
+#define SIXP_MAX_ADDR   ((__u8) 8)
+#define	SIZE		4096
+#define MAX_PTYS	SIXP_MAX_ADDR  /* Max number of TNCs in a 6PACK ring */
+
+/*
+ * Keep these off the stack.
+ */
+static __u8 ibuf[SIZE];	/* buffer for input operations */
+static __u8 obuf[SIZE];	/* buffer for sixpack_tx() */
+
+static int invalid_ports = 0;
+
+static char *usage_string = "usage: m6pack [-l] [-s speed] [-v] "
+			    "ttyinterface pty ...\n";
+
+static int dump_report = FALSE;
+static int logging = FALSE;
+
+static struct iface *pty[MAX_PTYS];
+static struct iface *tty;
+static int numptys;
+
+struct iface
+{
+	char		*name;		/* Interface name (/dev/???)	*/
+	int		fd;		/* File descriptor		*/
+	int		pty_id;		/* 6pack address asigned to pty */
+	__u8		seof;		/* leading SEOF of this frame	*/
+	__u8		databuf[SIZE];	/* TX buffer (data frames)	*/
+	__u8		cmdbuf[1];	/* TX buffer (command frames)	*/
+	__u8		*optr;		/* Next byte to transmit	*/
+	unsigned int	sixp_cnt;	/* 6pack-coded octets count	*/
+	unsigned int	decod_cnt;	/* 6pack-decoded octets cont	*/
+	unsigned int	errors;		/* 6PACK frame error count	*/
+	unsigned int	rxpackets;	/* RX frames count		*/
+	unsigned int	txpackets;	/* TX frames count		*/
+	unsigned long	rxbytes;	/* RX bytes count		*/
+	unsigned long	txbytes;	/* TX bytes count		*/
+};
+
+#define PTY_ID_TTY (-1)
+
+/* 6PACK "TNC Address" commands are special in that the address they
+ * carry is not the address of the destination TNC but the initial
+ * address for the firt TNC in the ring (when sent PC->TNC Ring), or
+ * the last TNC address+1 (when received TNC ring -> PC).  So we can't
+ * use the address in the command to select a pty to pass the
+ * command, and we have to keep track of what ptys have sent "TNC
+ * Address" commands to sent them back the response (until we modify
+ * the kernel 6pack driver to support multiple TNC's (i.e., network
+ * devices) on one serial port). We deliver the responses with a FIFO
+ * policy.
+ */
+static int cmd_addr_fifo[SIXP_MAX_ADDR];
+static int head; /* We retrieve from head position */
+static int tail; /* We insert at tail position */
+
+/* Masks to tell apart 6pack command and data frames
+ */
+#define SIXP_IS_DATA(x) ((((__u8)(x)) & (__u8)0xC0) == (__u8)0)
+#define SIXP_IS_CMD(x) !(SIXP_IS_DATA(x))
+
+/* Masks to split commands in opcode and TNC address
+ */
+#define SIXP_ADDR_MASK  ((__u8) (SIXP_MAX_ADDR-1))
+#define SIXP_CMD_MASK ((__u8) ~SIXP_ADDR_MASK)
+#define SIXP_CMD(x) (((__u8)x) & SIXP_CMD_MASK)
+#define SIXP_ADDR(x) (((__u8)x) & SIXP_ADDR_MASK)
+
+/* Macro to build a 6pack TNC command from opcode and TNC address
+ */
+#define SIXP_MAKE_CMD(opcode,addr) (((__u8)opcode) | ((__u8)addr))
+
+/* 6pack protocol commands (relevant bits only)
+ */
+#define SIXP_CMD_SEOF       ((__u8) 0x40)	/* start/end of 6pack frame */
+#define SIXP_CMD_TX_ORUN    ((__u8) 0x48)	/* transmit overrun */
+#define SIXP_CMD_RX_ORUN    ((__u8) 0x50)	/* receive overrun */
+#define SIXP_CMD_RX_BUF_OVL ((__u8) 0x58)	/* receive buffer overflow */
+#define SIXP_CMD_LED	    ((__u8) 0x60)	/* set LED status */
+#define SIXP_CMD_TX_1	    ((__u8) 0xA0)	/* TX counter + 1 */
+#define SIXP_CMD_RX_1	    ((__u8) 0x90)	/* RX counter + 1 */
+#define SIXP_CMD_DCD	    ((__u8) 0x88)	/* DCD state */
+#define SIXP_CMD_CAL	    ((__u8) 0xE0)	/* send calibration pattern */
+#define SIXP_CMD_ADDR	    ((__u8) 0xE8)	/* set TNC address */
+
+/* Valid checksum of a 6pack frame
+ */
+#define SIXP_CHKSUM ((__u8) 0xFF)
+
+static int sixpack_rx(struct iface *ifp, __u8 c, __u8 *tnc_addr, frame_t *type)
+{
+	int i, len;
+	__u8 checksum;
+	
+	/* Is it a data octect?
+	 */
+	if (SIXP_IS_DATA(c)) {
+		/* Decode the 6PACK octect and store the resultant
+		 * bits in the output buffer.
+		 */
+		switch (ifp->sixp_cnt % 4) {
+		case 0:
+			*ifp->optr = (c & 0x3F);
+			break;
+		case 1:
+			*ifp->optr++ |= (c & 0x30) << 2; 
+			*ifp->optr = (c & 0x0F);
+			break;
+		case 2:
+			*ifp->optr++ |= (c & 0x3C) << 2; 
+			*ifp->optr = (c & 0x03);
+			break;
+		default:
+			*ifp->optr++ |= (c & 0x3F) << 2; 
+		}
+		ifp->sixp_cnt++;
+		return 0;
+	}
+	
+	/* Nope, it's a command octect. See which kind of command.
+	 * Anything but a SEOF command is a one-octect command, so
+	 * process it immediately and return.
+	 */
+	if (SIXP_CMD(c) != SIXP_CMD_SEOF) {
+		if (SIXP_CMD(c) == SIXP_CMD_ADDR) {
+			/* 6PACK "TNC Address" commans are
+			 * "special". The address field must be
+			 * rewritten.
+			 */
+			if (PTY_ID_TTY == ifp->pty_id) {
+				/* TNC Ring -> pty
+				 * Dequeue a TNC Address request.
+				 */
+				*ifp->cmdbuf = SIXP_MAKE_CMD(SIXP_CMD(c),1);
+				*tnc_addr = cmd_addr_fifo[head];
+				head = (head + 1) % SIXP_MAX_ADDR;
+			}
+			else {
+				/* pty -> TNC Ring
+				 * Enqueue a TNC Address request.
+				 */
+				*ifp->cmdbuf = SIXP_MAKE_CMD(SIXP_CMD(c), 0);
+				*tnc_addr = 0;
+				cmd_addr_fifo[tail] = ifp->pty_id;
+				tail = (tail + 1) % SIXP_MAX_ADDR;
+			}
+		}
+		else {
+			/* We need a separate buffer here for 6PACK commands
+			 * as the protocol allows the transmission of command
+			 * frames in the middle of data frames. Don't touch
+			 * anything else! A data frame may be "en route".
+			 */
+			*ifp->cmdbuf = SIXP_CMD(c);
+			*tnc_addr = SIXP_ADDR(c);
+		}
+		/* Update statistics and return.
+		 */
+		ifp->rxpackets++;
+		ifp->rxbytes++;
+		*type = command;
+		return 1;
+	}
+	
+	/* We're dealing with a SEOF command.
+	 */
+	len = ifp->optr - ifp->databuf;
+	if (len > 0) {
+		if (len < 3) {
+			/* Data frames have at least 3 octets:
+			 *    TxDelay, Datum, CheckSum.
+			 * Signal error and reset state.
+			 */
+			goto error_reset_state;
+		}
+		
+		/* Now that we've decoded 6PACK octects,
+		 * check the checksum of the frame. 
+		 */
+		checksum = 0;
+		for (i = 0; i < len; i++) {
+			checksum += ifp->databuf[i];
+		}
+		/* Address of this frame must be taken from the
+		 * leading SEOF.
+		 */
+		*tnc_addr = SIXP_ADDR(ifp->seof);
+		checksum += *tnc_addr;
+		
+		if (checksum != SIXP_CHKSUM) {
+			/* Signal error and reset state.
+			 */
+			goto error_reset_state;
+		}
+		
+		/* Now remove checksum from the frame (this makes
+		 * sixpack_tx easier).
+		 */
+		len--;/* Minus Checksum */
+
+		/* Finally update statistics and return all
+		 * needed parameters
+		 */
+		ifp->rxpackets++;
+		ifp->rxbytes += len;
+		*type = data;
+	}
+
+	ifp->optr = ifp->databuf;
+	ifp->seof = c;
+	ifp->sixp_cnt = 0;
+	ifp->decod_cnt = 0;
+	return len;  
+	
+ error_reset_state:
+	ifp->errors++;
+	ifp->optr = ifp->databuf;
+	ifp->sixp_cnt = 0;
+	ifp->decod_cnt = 0;
+	return 0;
+}
+
+static void sixpack_tx(int fd, __u8 tnc_addr, __u8 *ibuf, int len, frame_t type)
+{
+	__u8 *ptr = obuf;
+	__u8 checksum;
+	int count, written;
+
+	if (type == command) {
+		if (SIXP_CMD(*ibuf) == SIXP_CMD_ADDR) {
+			/* 6PACK "TNC Address" commans are
+			 * "special". We must send them untouched here.
+			 */
+			*ptr++ = *ibuf;
+		}
+		else {
+			/* Commands, except SEOF, are 1 byte long.
+			 */
+			*ptr++ = SIXP_MAKE_CMD(SIXP_CMD(*ibuf), tnc_addr);
+		}
+	}
+	else {
+		*ptr++ = SIXP_MAKE_CMD(SIXP_CMD_SEOF, tnc_addr);
+		checksum = 0;
+		for (count = 0; count < len; count++) {
+			switch (count % 3) {
+			case 0:
+				*ptr++ = (ibuf[count] & 0x3F);
+				*ptr = (ibuf[count] & 0xC0) >> 2;
+				break;
+			case 1:
+				*ptr++ |= (ibuf[count] & 0x0F);
+				*ptr = (ibuf[count] & 0xF0) >> 2;
+				break;
+			default:
+				*ptr++ |= (ibuf[count] & 0x03);
+				*ptr++ = (ibuf[count] & 0xFC) >> 2;
+				break;
+			}
+			checksum += ibuf[count];
+		}
+
+		checksum += tnc_addr;
+		checksum = 0xFF - checksum;
+		switch (count % 3) {
+		case 0:
+			*ptr++ = (checksum & 0x3F);
+			*ptr++ = (checksum & 0xC0) >> 2;
+			break;
+		case 1:
+			*ptr++ |= (checksum & 0x0F);
+			*ptr++ = (checksum & 0xF0) >> 2;
+			break;
+		default:
+			*ptr++ |= (checksum & 0x03);
+			*ptr++ = (checksum & 0xFC) >> 2;
+			break;
+		}
+
+		/* Trailing SEOF doesn't carry TNC address
+		 */
+		*ptr++ = SIXP_MAKE_CMD(SIXP_CMD_SEOF, 0);
+	}
+
+	count = ptr - obuf;
+	written = 0;
+	ptr = obuf; 
+	while (count > 0) {
+		written = write (fd, ptr, count);
+		count -= written;
+		ptr += written;
+	}
+}
+
+static void sigterm_handler(int sig)
+{
+	int i;
+	
+	if (logging) {
+		syslog(LOG_INFO, "terminating on SIGTERM\n");
+		closelog();
+	}
+	
+	tty_unlock(tty->name);
+	for (i=0; i < numptys; i++) {
+		tty_unlock(pty[i]->name);
+	}
+	
+	close(tty->fd);
+	free(tty);
+	for (i = 0; i < numptys; i++) {
+		close(pty[i]->fd);
+		free(pty[i]);
+	}
+
+	exit(0);
+}
+
+static void sigusr1_handler(int sig)
+{
+	signal(SIGUSR1, sigusr1_handler);
+	dump_report = TRUE;
+}
+
+static void report(struct iface *tty, struct iface **pty, int numptys)
+{
+	int i;
+	long t;
+
+	time(&t);
+	syslog(LOG_INFO, "version %s.", VERSION);
+	syslog(LOG_INFO, "Status report at %s", ctime(&t));
+	syslog(LOG_INFO, "ttyinterface is %s (fd=%d)", tty->name, tty->fd);
+	for (i = 0; i < numptys; i++)
+		syslog(LOG_INFO, "pty%d is %s (fd=%d)", i, pty[i]->name,
+			pty[i]->fd);
+	syslog(LOG_INFO, "Invalid ports: %d", invalid_ports);
+	syslog(LOG_INFO, "Interface   TX frames TX bytes  RX frames RX "
+	       "bytes  Errors");
+	syslog(LOG_INFO, "%-11s %-9u %-9lu %-9u %-9lu %u",
+	       tty->name,
+	       tty->txpackets, tty->txbytes,
+	       tty->rxpackets, tty->rxbytes,
+	       tty->errors);
+	for (i = 0; i < numptys; i++) {
+		syslog(LOG_INFO, "%-11s %-9u %-9lu %-9u %-9lu %u",
+		       pty[i]->name,
+		       pty[i]->txpackets, pty[i]->txbytes,
+		       pty[i]->rxpackets, pty[i]->rxbytes,
+		       pty[i]->errors);
+	}
+	return;
+}
+
+int main(int argc, char *argv[])
+{
+	__u8 *icp, tnc_addr;
+	int topfd;
+	fd_set readfd;
+	int retval, i, size, len;
+	int speed	= -1;
+	frame_t type;
+
+	head = tail = 0;
+	while ((size = getopt(argc, argv, "ls:v")) != -1) {
+		switch (size) {
+		case 'l':
+			logging = TRUE;
+			break;
+		case 's':
+			speed = atoi(optarg);
+			break;
+		case 'v':
+			printf("m6pack: %s\n", VERSION);
+			return 1;
+		case ':':
+		case '?':
+			fprintf(stderr, usage_string);
+			return 1;
+		}
+	}
+
+	if ((argc - optind) < 2) {
+		fprintf(stderr, usage_string);
+		return 1;
+	}
+	if ((numptys = argc - optind - 1) > MAX_PTYS) {
+		fprintf(stderr, "m6pack: max %d pty interfaces allowed.\n",
+			MAX_PTYS);
+		return 1;
+	}
+
+	/*
+	 * Check for lock files before opening any TTYs
+	 */
+	if (tty_is_locked(argv[optind])) {
+		fprintf(stderr, "m6pack: tty %s is locked by another "
+			"process\n", argv[optind]);
+		return 1;
+	}
+	for (i = 0; i < numptys; i++) {
+		if (tty_is_locked(argv[optind + i + 1])) {
+			fprintf(stderr, "m6pack: tty %s is locked by "
+				"another process\n", argv[optind + i + 1]);
+			return 1;
+		}
+	}
+
+	/*
+	 * Open and configure the tty interface. Open() is
+	 * non-blocking so it won't block regardless of the modem
+	 * status lines.
+	 */
+	if ((tty = calloc(1, sizeof(struct iface))) == NULL) {
+		perror("m6pack: malloc");
+		return 1;
+	}
+
+	if ((tty->fd = open(argv[optind], O_RDWR | O_NDELAY)) == -1) {
+		perror("m6pack: open");
+		return 1;
+	}
+
+	tty->name = argv[optind];
+	if (speed != -1) tty_speed(tty->fd, speed);
+	tty_raw(tty->fd, FALSE);
+	tty->pty_id = PTY_ID_TTY;
+	tty->optr = tty->databuf;
+	topfd = tty->fd;
+	/*
+	 * Make it block again...
+	 */
+	fcntl(tty->fd, F_SETFL, 0);
+
+	/*
+	 * Open and configure the pty interfaces
+	 */
+	for (i = 0; i < numptys; i++) {
+		if ((pty[i] = calloc(1, sizeof(struct iface))) == NULL) {
+			perror("m6pack: malloc");
+			return 1;
+		}
+		if ((pty[i]->fd = open(argv[optind + i + 1], O_RDWR)) == -1) {
+			perror("m6pack: open");
+			return 1;
+		}
+		pty[i]->name = argv[optind + i + 1];
+		tty_raw(pty[i]->fd, FALSE);
+		pty[i]->pty_id = i;
+		pty[i]->optr = pty[i]->databuf;
+		topfd = (pty[i]->fd > topfd) ? pty[i]->fd : topfd;
+	}
+
+	/*
+	 * Now all the ports are open, lock them.
+	 */
+	tty_lock(argv[optind]);
+	for (i = 0; i < numptys; i++)
+		tty_lock(argv[optind + i + 1]);
+
+	signal(SIGHUP, SIG_IGN);
+	signal(SIGUSR1, sigusr1_handler);
+	signal(SIGTERM, sigterm_handler);
+
+	if (!daemon_start(FALSE)) {
+		fprintf(stderr, "m6pack: cannot become a daemon\n");
+		return 1;
+	}
+
+	if (logging) {
+		openlog("m6pack", LOG_PID, LOG_DAEMON);
+		syslog(LOG_INFO, "starting");
+	}
+
+	/*
+	 * Loop until an error occurs on a read.
+	 */
+	while (TRUE) {
+		FD_ZERO(&readfd);
+		FD_SET(tty->fd, &readfd);
+		for (i = 0; i < numptys; i++)
+			FD_SET(pty[i]->fd, &readfd);
+
+		errno = 0;
+		retval = select(topfd + 1, &readfd, NULL, NULL, NULL);
+
+		if (retval == -1) {
+			if (dump_report) {
+				if (logging)
+					report(tty, pty, numptys);
+				dump_report = FALSE;
+				continue;
+			} else {
+				perror("m6pack: select");
+				continue;
+			}
+		}
+
+
+		/*
+		 * A character has arrived on the ttyinterface.
+		 */
+		if (FD_ISSET(tty->fd, &readfd)) {
+			if ((size = read(tty->fd, ibuf, SIZE)) < 0 
+			    && errno != EINTR) {
+				if (logging)
+					syslog(LOG_ERR, "tty->fd: %m");
+				break;
+			}
+
+			for (icp = ibuf; size > 0; size--, icp++) {
+				if ((len = sixpack_rx(tty,*icp,&tnc_addr,
+						      &type)) != 0) {
+					if (tnc_addr <= numptys) {
+						sixpack_tx(pty[tnc_addr]->fd,
+							   0,
+							   (type == data) ? 
+							   tty->databuf : 
+							   tty->cmdbuf,
+							   len,
+							   type);
+						pty[tnc_addr]->txpackets++;
+						pty[tnc_addr]->txbytes += len;
+					} else
+						invalid_ports++;
+				}
+			}
+		}
+
+		for (i = 0; i < numptys; i++) {
+			/*
+			 * A character has arrived on pty[i].
+			 */
+			if (FD_ISSET(pty[i]->fd, &readfd)) {
+				if ((size = read(pty[i]->fd, ibuf, SIZE)) < 0
+				    && errno != EINTR) {
+					if (logging)
+						syslog(LOG_ERR,
+						       "pty[%d]->fd: %m\n",i);
+					goto end;
+				}
+
+				for (icp = ibuf; size > 0; size--, icp++) {
+					if ((len = sixpack_rx(pty[i],
+							      *icp,
+							      &tnc_addr,
+							      &type)) != 0) {
+						sixpack_tx(tty->fd, i,
+							   (type == data) ?
+							   pty[i]->databuf :
+							   pty[i]->cmdbuf,
+							   len, type);
+						tty->txpackets++;
+						tty->txbytes += len;
+					}
+				}
+			}
+		}
+	}
+
+      end:
+	if (logging)
+		closelog();
+
+	close(tty->fd);
+	free(tty);
+
+	for (i = 0; i < numptys; i++) {
+		close(pty[i]->fd);
+		free(pty[i]);
+	}
+	return 1;
+}