Add dial tone detection to disable echo suppressor

This is a big one:

Startup process was hacked. Several state machines do the startup process now:
- system startup
- PSTN startup
- PSTN restart
- 5 state machines to do multiple port unblocking/blocking

.gitignore

@@ -0,0 +1,46 @@
+Makefile
+Makefile.in
+.deps
+.libs
+*.o
+*.lo
+*.la
+*.pc
+aclocal.m4
+autom4te.cache
+config.h*
+config.sub
+config.log
+config.status
+config.guess
+configure
+compile
+depcomp
+missing
+ltmain.sh
+install-sh
+stamp-h1
+#libosmo-abis-*
+tests/*_test
+*~
+
+# libtool and e.g. arm-poky-linux-gnueabi-libtool
+*libtool
+
+.tarball-version
+.version
+.dirstamp
+
+# tests
+tests/atconfig
+tests/package.m4
+tests/testsuite
+tests/testsuite.log
+
+# vi/vim files
+*.sw?
+
+src/libg711/libg711.a
+src/libecho/libecho.a
+src/osmo-v5-le
+tests/answer_detect

Makefile

@@ -1,11 +0,0 @@
-LIBS=-lasan -ltalloc -losmocore -losmovty -losmogsm -losmoctrl -losmoabis
-CFLAGS=-Wall -DPACKAGE_VERSION=\"0.0\"
-
-%.o: %.c
-	$(CC) $(CFLAGS) -o $@ -c $^
-
-v5le: main.o v5x_data.o lapv5.o
-	$(CC) -o $@ $^ $(LIBS)
-
-clean:
-	@rm v5le *.o

Makefile.am

@@ -0,0 +1,8 @@
+ACLOCAL_AMFLAGS = -I m4
+
+AM_CPPFLAGS = $(all_includes)
+SUBDIRS = src tests
+
+dist-hook:
+	echo $(VERSION) > $(distdir)/.tarball-version
+

configure.ac

@@ -0,0 +1,116 @@
+AC_INIT([osmo-v5],
+	m4_esyscmd([./git-version-gen .tarball-version]),
+	[openbsc@lists.osmocom.org])
+
+dnl *This* is the root dir, even if an install-sh exists in ../ or ../../
+AC_CONFIG_AUX_DIR([.])
+
+AM_INIT_AUTOMAKE([foreign dist-bzip2 no-dist-gzip 1.6 subdir-objects])
+AC_CONFIG_TESTDIR(tests)
+
+CFLAGS="$CFLAGS -std=gnu11"
+
+dnl kernel style compile messages
+m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
+
+dnl include release helper
+RELMAKE='-include osmo-release.mk'
+AC_SUBST([RELMAKE])
+
+dnl checks for programs
+AC_PROG_MAKE_SET
+AC_PROG_CC
+AC_PROG_INSTALL
+LT_INIT([pic-only])
+
+dnl patching ${archive_cmds} to affect generation of file "libtool" to fix linking with clang
+AS_CASE(["$LD"],[*clang*],
+  [AS_CASE(["${host_os}"],
+     [*linux*],[archive_cmds='$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-soname $wl$soname -o $lib'])])
+
+dnl check for pkg-config (explained in detail in libosmocore/configure.ac)
+AC_PATH_PROG(PKG_CONFIG_INSTALLED, pkg-config, no)
+if test "x$PKG_CONFIG_INSTALLED" = "xno"; then
+        AC_MSG_WARN([You need to install pkg-config])
+fi
+PKG_PROG_PKG_CONFIG([0.20])
+
+AC_CONFIG_MACRO_DIR([m4])
+
+CFLAGS="$CFLAGS -Wall"
+CPPFLAGS="$CPPFLAGS -Wall"
+
+AC_ARG_ENABLE(sanitize,
+	[AS_HELP_STRING(
+		[--enable-sanitize],
+		[Compile with address sanitizer enabled],
+	)],
+	[sanitize=$enableval], [sanitize="no"])
+if test x"$sanitize" = x"yes"
+then
+	CFLAGS="$CFLAGS -fsanitize=address -fsanitize=undefined"
+	CPPFLAGS="$CPPFLAGS -fsanitize=address -fsanitize=undefined"
+fi
+
+# The following test is taken from WebKit's webkit.m4
+saved_CFLAGS="$CFLAGS"
+CFLAGS="$CFLAGS -fvisibility=hidden "
+AC_MSG_CHECKING([if ${CC} supports -fvisibility=hidden])
+AC_COMPILE_IFELSE([AC_LANG_SOURCE([char foo;])],
+      [ AC_MSG_RESULT([yes])
+        SYMBOL_VISIBILITY="-fvisibility=hidden"],
+        AC_MSG_RESULT([no]))
+CFLAGS="$saved_CFLAGS"
+AC_SUBST(SYMBOL_VISIBILITY)
+
+dnl Generate the output
+AM_CONFIG_HEADER(config.h)
+
+PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 1.8.0)
+PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty >= 1.8.0)
+PKG_CHECK_MODULES(LIBOSMOGSM, libosmogsm >= 1.8.0)
+PKG_CHECK_MODULES(LIBOSMOCTRL, libosmoctrl >= 1.8.0)
+PKG_CHECK_MODULES(LIBOSMOABIS, libosmoabis >= 1.3.0)
+PKG_CHECK_MODULES(LIBOSMOISDN, libosmoisdn >= 1.8.0)
+
+AC_ARG_ENABLE(sanitize,
+	[AS_HELP_STRING(
+		[--enable-sanitize],
+		[Compile with address sanitizer enabled],
+	)],
+	[sanitize=$enableval], [sanitize="no"])
+if test x"$sanitize" = x"yes"
+then
+	CFLAGS="$CFLAGS -fsanitize=address -fsanitize=undefined"
+	CPPFLAGS="$CPPFLAGS -fsanitize=address -fsanitize=undefined"
+fi
+
+AC_ARG_ENABLE(werror,
+	[AS_HELP_STRING(
+		[--enable-werror],
+		[Turn all compiler warnings into errors, with exceptions:
+		 a) deprecation (allow upstream to mark deprecation without breaking builds);
+		 b) "#warning" pragmas (allow to remind ourselves of errors without breaking builds)
+		]
+	)],
+	[werror=$enableval], [werror="no"])
+if test x"$werror" = x"yes"
+then
+	WERROR_FLAGS="-Werror"
+	WERROR_FLAGS+=" -Wno-error=deprecated -Wno-error=deprecated-declarations"
+	WERROR_FLAGS+=" -Wno-error=cpp" # "#warning"
+	CFLAGS="$CFLAGS $WERROR_FLAGS"
+	CPPFLAGS="$CPPFLAGS $WERROR_FLAGS"
+fi
+
+AX_CHECK_X86_FEATURES()
+
+AC_MSG_RESULT([CFLAGS="$CFLAGS"])
+AC_MSG_RESULT([CPPFLAGS="$CPPFLAGS"])
+
+AC_OUTPUT(
+	src/libecho/Makefile
+	src/libg711/Makefile
+	src/Makefile
+	tests/Makefile
+	Makefile)

git-version-gen

@@ -0,0 +1,151 @@
+#!/bin/sh
+# Print a version string.
+scriptversion=2010-01-28.01
+
+# Copyright (C) 2007-2010 Free Software Foundation, Inc.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# This script is derived from GIT-VERSION-GEN from GIT: http://git.or.cz/.
+# It may be run two ways:
+# - from a git repository in which the "git describe" command below
+#   produces useful output (thus requiring at least one signed tag)
+# - from a non-git-repo directory containing a .tarball-version file, which
+#   presumes this script is invoked like "./git-version-gen .tarball-version".
+
+# In order to use intra-version strings in your project, you will need two
+# separate generated version string files:
+#
+# .tarball-version - present only in a distribution tarball, and not in
+#   a checked-out repository.  Created with contents that were learned at
+#   the last time autoconf was run, and used by git-version-gen.  Must not
+#   be present in either $(srcdir) or $(builddir) for git-version-gen to
+#   give accurate answers during normal development with a checked out tree,
+#   but must be present in a tarball when there is no version control system.
+#   Therefore, it cannot be used in any dependencies.  GNUmakefile has
+#   hooks to force a reconfigure at distribution time to get the value
+#   correct, without penalizing normal development with extra reconfigures.
+#
+# .version - present in a checked-out repository and in a distribution
+#   tarball.  Usable in dependencies, particularly for files that don't
+#   want to depend on config.h but do want to track version changes.
+#   Delete this file prior to any autoconf run where you want to rebuild
+#   files to pick up a version string change; and leave it stale to
+#   minimize rebuild time after unrelated changes to configure sources.
+#
+# It is probably wise to add these two files to .gitignore, so that you
+# don't accidentally commit either generated file.
+#
+# Use the following line in your configure.ac, so that $(VERSION) will
+# automatically be up-to-date each time configure is run (and note that
+# since configure.ac no longer includes a version string, Makefile rules
+# should not depend on configure.ac for version updates).
+#
+# AC_INIT([GNU project],
+#         m4_esyscmd([build-aux/git-version-gen .tarball-version]),
+#         [bug-project@example])
+#
+# Then use the following lines in your Makefile.am, so that .version
+# will be present for dependencies, and so that .tarball-version will
+# exist in distribution tarballs.
+#
+# BUILT_SOURCES = $(top_srcdir)/.version
+# $(top_srcdir)/.version:
+#	echo $(VERSION) > $@-t && mv $@-t $@
+# dist-hook:
+#	echo $(VERSION) > $(distdir)/.tarball-version
+
+case $# in
+    1) ;;
+    *) echo 1>&2 "Usage: $0 \$srcdir/.tarball-version"; exit 1;;
+esac
+
+tarball_version_file=$1
+nl='
+'
+
+# First see if there is a tarball-only version file.
+# then try "git describe", then default.
+if test -f $tarball_version_file
+then
+    v=`cat $tarball_version_file` || exit 1
+    case $v in
+	*$nl*) v= ;; # reject multi-line output
+	[0-9]*) ;;
+	*) v= ;;
+    esac
+    test -z "$v" \
+	&& echo "$0: WARNING: $tarball_version_file seems to be damaged" 1>&2
+fi
+
+if test -n "$v"
+then
+    : # use $v
+elif
+       v=`git describe --abbrev=4 HEAD 2>/dev/null \
+	  || git describe --abbrev=4 --match='v*' HEAD 2>/dev/null` \
+    && case $v in
+	 [0-9]*) ;;
+	 v[0-9]*) ;;
+	 *) (exit 1) ;;
+       esac
+then
+    # Is this a new git that lists number of commits since the last
+    # tag or the previous older version that did not?
+    #   Newer: v6.10-77-g0f8faeb
+    #   Older: v6.10-g0f8faeb
+    case $v in
+	*-*-*) : git describe is okay three part flavor ;;
+	*-*)
+	    : git describe is older two part flavor
+	    # Recreate the number of commits and rewrite such that the
+	    # result is the same as if we were using the newer version
+	    # of git describe.
+	    vtag=`echo "$v" | sed 's/-.*//'`
+	    numcommits=`git rev-list "$vtag"..HEAD | wc -l`
+	    v=`echo "$v" | sed "s/\(.*\)-\(.*\)/\1-$numcommits-\2/"`;
+	    ;;
+    esac
+
+    # Change the first '-' to a '.', so version-comparing tools work properly.
+    # Remove the "g" in git describe's output string, to save a byte.
+    v=`echo "$v" | sed 's/-/./;s/\(.*\)-g/\1-/'`;
+else
+    v=UNKNOWN
+fi
+
+v=`echo "$v" |sed 's/^v//'`
+
+# Don't declare a version "dirty" merely because a time stamp has changed.
+git status > /dev/null 2>&1
+
+dirty=`sh -c 'git diff-index --name-only HEAD' 2>/dev/null` || dirty=
+case "$dirty" in
+    '') ;;
+    *) # Append the suffix only if there isn't one already.
+	case $v in
+	  *-dirty) ;;
+	  *) v="$v-dirty" ;;
+	esac ;;
+esac
+
+# Omit the trailing newline, so that m4_esyscmd can use the result directly.
+echo "$v" | tr -d '\012'
+
+# Local variables:
+# eval: (add-hook 'write-file-hooks 'time-stamp)
+# time-stamp-start: "scriptversion="
+# time-stamp-format: "%:y-%02m-%02d.%02H"
+# time-stamp-end: "$"
+# End:

lapv5.h

@@ -1,21 +0,0 @@
-#pragma once
-
-#include <osmocom/abis/lapd.h>
-
-struct lapv5_instance {
-	struct llist_head list;		/* list of LAPV5 instances */
-	bool network_side;
-
-	void (*transmit_cb)(struct msgb *msg, void *cbdata);
-	void *transmit_cbdata;
-	void (*receive_cb)(struct osmo_dlsap_prim *odp, uint16_t dladdr, void *rx_cbdata);
-	void *receive_cbdata;
-
-	struct lapd_profile profile;	/* must be a copy */
-
-	struct llist_head sap_list;	/* list of SAP/datalinks in this instance */
-	int pcap_fd;			/* PCAP file descriptor */
-	char *name;			/* human-readable name */
-};
-
-int lapv5ef_rx(struct v5x_link *link, struct msgb *msg);

m4/ax_check_x86_features.m4

@@ -0,0 +1,13 @@
+AC_DEFUN([AX_CHECK_X86_FEATURES],
+ [m4_foreach_w(
+   [ax_x86_feature],
+   [mmx popcnt sse sse2 sse3 sse4.1 sse4.2 sse4a avx avx2 avx512f fma fma4 bmi bmi2],
+   [AX_GCC_X86_CPU_SUPPORTS(ax_x86_feature,
+     [X86_FEATURE_CFLAGS="$X86_FEATURE_CFLAGS -m[]ax_x86_feature"],
+     [])
+  ])
+  AC_SUBST([X86_FEATURE_CFLAGS])
+  m4_ifval([$1],[$1],
+    [CFLAGS="$CFLAGS $X86_FEATURE_CFLAGS"])
+  $2
+])

m4/ax_gcc_x86_cpu_supports.m4

@@ -0,0 +1,44 @@
+AC_DEFUN_ONCE([_AX_GCC_X86_CPU_INIT],
+ [AC_LANG_PUSH([C])
+  AC_CACHE_CHECK([for gcc __builtin_cpu_init function],
+    [ax_cv_gcc_check_x86_cpu_init],
+    [AC_RUN_IFELSE(
+      [AC_LANG_PROGRAM([#include <stdlib.h>],
+        [__builtin_cpu_init ();])
+      ],
+      [ax_cv_gcc_check_x86_cpu_init=yes],
+      [ax_cv_gcc_check_x86_cpu_init=no])])
+  AC_LANG_POP([C])
+  AS_IF([test "X$ax_cv_gcc_check_x86_cpu_init" = "Xno"],
+    [AC_MSG_ERROR([Need GCC to support X86 CPU features tests])])
+])
+
+AC_DEFUN([AX_GCC_X86_CPU_SUPPORTS],
+  [AC_REQUIRE([AC_PROG_CC])
+   AC_REQUIRE([_AX_GCC_X86_CPU_INIT])
+   AC_LANG_PUSH([C])
+   AS_VAR_PUSHDEF([gcc_x86_feature], [AS_TR_SH([ax_cv_gcc_x86_cpu_supports_$1])])
+   AC_CACHE_CHECK([for x86 $1 instruction support],
+     [gcc_x86_feature],
+     [AC_RUN_IFELSE(
+       [AC_LANG_PROGRAM( [#include <stdlib.h> ],
+       [ __builtin_cpu_init ();
+         if (__builtin_cpu_supports("$1"))
+           return 0;
+         return 1;
+        ])],
+        [gcc_x86_feature=yes],
+        [gcc_x86_feature=no]
+     )]
+   )
+   AC_LANG_POP([C])
+   AS_VAR_IF([gcc_x86_feature],[yes],
+         [AC_DEFINE(
+           AS_TR_CPP([HAVE_$1_INSTRUCTIONS]),
+           [1],
+           [Define if $1 instructions are supported])
+          $2],
+          [$3]
+         )
+   AS_VAR_POPDEF([gcc_x86_feature])
+])

osmo-v5le.cfg

@@ -1,12 +0,0 @@
-e1_input
- e1_line 0 driver dahdi
- e1_line 0 port 7
-
-log stderr
- logging filter all 1
- logging color 1
- logging print category-hex 0
- logging print category 1
- logging print file 1
- logging level llapd debug
- logging level linp debug

src/Makefile.am

@@ -0,0 +1,31 @@
+AM_CPPFLAGS = $(all_includes)
+AM_CFLAGS= -Wall -Wextra -g $(LIBOSMOCORE_CFLAGS) $(LIBOSMOGSM_CFLAGS) $(LIBOSMOVTY_CFLAGS) $(LIBOSMOABIS_CFLAGS) $(LIBOSMOCTRL_CFLAGS)
+AM_LDFLAGS = $(COVERAGE_LDFLAGS)
+COMMONLIBS = $(LIBOSMOCORE_LIBS) $(LIBOSMOGSM_LIBS) $(LIBOSMOVTY_LIBS) $(LIBOSMOABIS_LIBS) $(LIBOSMOCTRL_LIBS)
+
+SUBDIRS = libecho libg711
+
+bin_PROGRAMS = osmo-v5-le
+
+osmo_v5_le_SOURCES = logging.c \
+		     ph_socket.c \
+		     v5x_data.c \
+		     v5le_vty.c \
+		     lapv5.c \
+		     layer1.c \
+		     v5x_protocol.c \
+		     v5x_l1_fsm.c \
+		     v5x_le_ctrl_fsm.c \
+		     v5x_le_port_fsm.c \
+		     v5x_le_pstn_fsm.c \
+		     v52_le_lcp_fsm.c \
+		     v52_le_bcc_fsm.c \
+		     v52_le_pp_fsm.c \
+		     v5x_le_management.c \
+		     main.c
+
+osmo_v5_le_LDADD = $(COMMON_LA) \
+		   $(COMMONLIBS) \
+		   libecho/libecho.a \
+		   libg711/libg711.a \
+		   -lm

src/lapv5.c

@@ -22,24 +22,26 @@
  *
  */
 
-#include "v5x_internal.h"
-#include "v5x_protocol.h"
-#include "lapv5.h"
-
 #include <stdio.h>
 #include <string.h>
 #include <errno.h>
 
 #include <osmocom/core/linuxlist.h>
-#include <osmocom/core/logging.h>
 #include <osmocom/core/talloc.h>
 #include <osmocom/core/msgb.h>
 #include <osmocom/core/timer.h>
 #include <osmocom/abis/lapd.h>
 #include <osmocom/abis/lapd_pcap.h>
 
-#define LAPD_ADDR2(sapi, cr) ((((sapi) & 0x3f) << 2) | (((cr) & 0x1) << 1))
-#define LAPD_ADDR3(tei) ((((tei) & 0x7f) << 1) | 0x1)
+#include "v5x_internal.h"
+#include "v5x_protocol.h"
+#include "v5x_le_port_fsm.h"
+#include "lapv5.h"
+#include "layer1.h"
+#include "logging.h"
+
+#define LAPD_ADDR1(sapi, cr) ((((sapi) & 0x3f) << 2) | (((cr) & 0x1) << 1))
+#define LAPD_ADDR2(tei) ((((tei) & 0x7f) << 1) | 0x1)
 
 #define LAPD_ADDR_SAPI(addr) ((addr) >> 2)
 #define LAPD_ADDR_CR(addr) (((addr) >> 1) & 0x1)
@@ -132,15 +134,16 @@ static struct lapv5_sap *lapv5_sap_alloc(struct lapv5_instance *li, uint16_t v5d
 	if (!sap)
 		return NULL;
 
-	LOGP(DLLAPD, LOGL_NOTICE, "(%s): LAPV5 Allocating SAP for V5_DLADDR=%u (dl=%p, sap=%p)\n",
+	LOGP(DLLAPD, LOGL_DEBUG, "(%s): LAPV5 Allocating SAP for V5_DLADDR=%u (dl=%p, sap=%p)\n",
 	     name, v5dladdr, &sap->dl, sap);
 
+	sap->li = li;
 	sap->dladdr = v5dladdr;
 	dl = &sap->dl;
 	profile = &li->profile;
 
 	k = profile->k[0];
-	LOGP(DLLAPD, LOGL_NOTICE, "(%s): k=%d N200=%d N201=%d T200=%d.%d T203=%d.%d\n",
+	LOGP(DLLAPD, LOGL_DEBUG, "(%s): k=%d N200=%d N201=%d T200=%d.%d T203=%d.%d\n",
 		name, k, profile->n200, profile->n201, profile->t200_sec,
 		profile->t200_usec, profile->t203_sec, profile->t203_usec);
 	lapd_dl_init2(dl, k, 128, profile->n201, name);
@@ -152,8 +155,8 @@ static struct lapv5_sap *lapv5_sap_alloc(struct lapv5_instance *li, uint16_t v5d
 	dl->t200_sec = profile->t200_sec; dl->t200_usec = profile->t200_usec;
 	dl->t203_sec = profile->t203_sec; dl->t203_usec = profile->t203_usec;
 	dl->lctx.dl = &sap->dl;
-	dl->lctx.sapi = v5dladdr & 0xff;
-	dl->lctx.tei = v5dladdr >> 8;
+	dl->lctx.sapi = v5dladdr >> 7;
+	dl->lctx.tei = v5dladdr & 0x7f;
 	dl->lctx.n201 = profile->n201;
 
 	lapd_set_mode(&sap->dl, (li->network_side) ? LAPD_MODE_NETWORK : LAPD_MODE_USER);
@@ -166,7 +169,7 @@ static struct lapv5_sap *lapv5_sap_alloc(struct lapv5_instance *li, uint16_t v5d
 /* Free SAP instance, including the datalink */
 static void lapv5_sap_free(struct lapv5_sap *sap)
 {
-	LOGSAP(sap, LOGL_NOTICE, "LAPV5 Freeing SAP for DLADDR=%u (dl=%p, sap=%p)\n", sap->dladdr, &sap->dl, sap);
+	LOGSAP(sap, LOGL_DEBUG, "LAPV5 Freeing SAP for DLADDR=%u (dl=%p, sap=%p)\n", sap->dladdr, &sap->dl, sap);
 
 	/* free datalink structures and timers */
 	lapd_dl_exit(&sap->dl);
@@ -175,39 +178,41 @@ static void lapv5_sap_free(struct lapv5_sap *sap)
 	talloc_free(sap);
 }
 
-/* General input function for any data received for this LAPV5 instance */
-int lapv5_receive(struct lapv5_instance *li, struct msgb *msg, int *error)
+/* Receive Data (PH-DATA indication) on the given LAPD Instance */
+int lapv5_ph_data_ind(struct lapv5_instance *li, struct msgb *msg, int *error)
 {
 	struct lapd_msg_ctx lctx;
 	struct lapv5_sap *sap;
 	uint16_t dladdr;
-	bool is_isdn;
 	int i;
 
 	/* write to PCAP file, if enabled. */
 	osmo_pcap_lapd_write(li->pcap_fd, OSMO_LAPD_PCAP_INPUT, msg);
 
+	if (!li->enabled) {
+		LOGLI(li, LOGL_DEBUG, "LAPV5 frame ignored, because DL is disabled.\n");
+		msgb_free(msg);
+		return -EINVAL;
+	}
+
+	msgb_pull(msg, msg->l2h - msg->data);
+
 	LOGLI(li, LOGL_DEBUG, "RX: %s\n", osmo_hexdump(msg->data, msg->len));
 	if (msg->len < 2) {
 		LOGLI(li, LOGL_ERROR, "LAPV5 frame receive len %d < 2, ignoring\n", msg->len);
 		*error = LAPD_ERR_BAD_LEN;
+		msgb_free(msg);
 		return -EINVAL;
 	};
-	msg->l2h = msg->data;
 
 	memset(&lctx, 0, sizeof(lctx));
 
 	i = 0;
 	/* adress field */
-	dladdr = v51_l3_addr_dec(msg->l2h[0] << 8 | msg->l2h[1], &is_isdn);
-	if (!is_isdn) {
-		LOGLI(li, LOGL_ERROR, "LAPV5 frame with single-octet addr not permitted\n");
-		*error = LAPD_ERR_BAD_LEN;
-		return -EINVAL;
-	};
+	dladdr = ((msg->l2h[0] & 0xfe) << 5) | (msg->l2h[1] >> 1);
 	lctx.lpd = 0;
-	lctx.tei = dladdr >> 8;
-	lctx.sapi = dladdr & 0xff;
+	lctx.sapi = dladdr >> 7;
+	lctx.tei = dladdr & 0x7f;
 	lctx.cr = LAPD_ADDR_CR(msg->l2h[0]);
 	i += 2;
 
@@ -219,6 +224,7 @@ int lapv5_receive(struct lapv5_instance *li, struct msgb *msg, int *error)
 		if (msg->len < 4) {
 			LOGLI(li, LOGL_ERROR, "LAPV5 I frame receive len %d < 4, ignoring\n", msg->len);
 			*error = LAPD_ERR_BAD_LEN;
+			msgb_free(msg);
 			return -EINVAL;
 		}
 		lctx.n_recv = LAPD_CTRL_Nr(msg->l2h[i]);
@@ -230,6 +236,7 @@ int lapv5_receive(struct lapv5_instance *li, struct msgb *msg, int *error)
 		if (msg->len < 4 && i == 3) {
 			LOGLI(li, LOGL_ERROR, "LAPV5 S frame receive len %d < 4, ignoring\n", msg->len);
 			*error = LAPD_ERR_BAD_LEN;
+			msgb_free(msg);
 			return -EINVAL;
 		}
 		lctx.n_recv = LAPD_CTRL_Nr(msg->l2h[i]);
@@ -270,34 +277,34 @@ int lapv5_receive(struct lapv5_instance *li, struct msgb *msg, int *error)
 	return lapd_ph_data_ind(msg, &lctx);
 }
 
-/* Start a (user-side) SAP for the specified TEI/SAPI on the LAPD instance */
-int lapv5_sap_start(struct lapv5_instance *li, uint16_t dladdr)
+/* Start a (LE-side) SAP for the specified TEI/SAPI on the LAPD instance */
+int lapv5_dl_est_req(struct lapv5_instance *li, uint16_t dladdr)
 {
 	struct lapv5_sap *sap;
 	struct osmo_dlsap_prim dp;
 	struct msgb *msg;
 
 	sap = lapv5_sap_find(li, dladdr);
-	if (sap)
-		return -EEXIST;
-
-	sap = lapv5_sap_alloc(li, dladdr);
-	if (!sap)
-		return -ENOMEM;
+	if (!sap) {
+		sap = lapv5_sap_alloc(li, dladdr);
+		if (!sap)
+			return -ENOMEM;
+	}
 
-	LOGSAP(sap, LOGL_NOTICE, "LAPV5 DL-ESTABLISH request DLADDR=%u\n", dladdr);
+	LOGSAP(sap, LOGL_DEBUG, "LAPV5 DL-ESTABLISH request DLADDR=%u\n", dladdr);
 
 	/* prepare prim */
 	msg = msgb_alloc_headroom(DLSAP_MSGB_SIZE, DLSAP_MSGB_HEADROOM, "DL EST");
 	msg->l3h = msg->data;
+	memset(&dp, 0, sizeof(dp));
         osmo_prim_init(&dp.oph, 0, PRIM_DL_EST, PRIM_OP_REQUEST, msg);
 
         /* send to L2 */
         return lapd_recv_dlsap(&dp, &sap->dl.lctx);
 }
 
-/* Stop a (user-side) SAP for the specified TEI/SAPI on the LAPD instance */
-int lapv5_sap_stop(struct lapv5_instance *li, uint16_t dladdr)
+/* Stop a (LE-side) SAP for the specified TEI/SAPI on the LAPD instance */
+int lapv5_dl_rel_req(struct lapv5_instance *li, uint16_t dladdr)
 {
 	struct lapv5_sap *sap;
 	struct osmo_dlsap_prim dp;
@@ -307,11 +314,12 @@ int lapv5_sap_stop(struct lapv5_instance *li, uint16_t dladdr)
 	if (!sap)
 		return -ENODEV;
 
-	LOGSAP(sap, LOGL_NOTICE, "LAPV5 DL-RELEASE request DLADDR=%u\n", dladdr);
+	LOGSAP(sap, LOGL_DEBUG, "LAPV5 DL-RELEASE request DLADDR=%u\n", dladdr);
 
 	/* prepare prim */
 	msg = msgb_alloc_headroom(DLSAP_MSGB_SIZE, DLSAP_MSGB_HEADROOM, "DL REL");
 	msg->l3h = msg->data;
+	memset(&dp, 0, sizeof(dp));
         osmo_prim_init(&dp.oph, 0, PRIM_DL_REL, PRIM_OP_REQUEST, msg);
 
         /* send to L2 */
@@ -319,24 +327,25 @@ int lapv5_sap_stop(struct lapv5_instance *li, uint16_t dladdr)
 }
 
 /* Transmit Data (DL-DATA request) on the given LAPD Instance / DLADDR */
-void lapv5_transmit(struct lapv5_instance *li, uint8_t dladdr, struct msgb *msg)
+int lapv5_dl_data_req(struct lapv5_instance *li, uint16_t dladdr, struct msgb *msg)
 {
 	struct lapv5_sap *sap;
 	struct osmo_dlsap_prim dp;
 
 	sap = lapv5_sap_find(li, dladdr);
 	if (!sap) {
-		LOGLI(li, LOGL_INFO, "LAPV5 Tx on unknown DLADDR=%u\n", dladdr);
+		LOGLI(li, LOGL_NOTICE, "LAPV5 Tx on unknown DLADDR=%u\n", dladdr);
 		msgb_free(msg);
-		return;
+		return -EINVAL;
 	}
 
 	/* prepare prim */
 	msg->l3h = msg->data;
-        osmo_prim_init(&dp.oph, 0, PRIM_DL_DATA, PRIM_OP_REQUEST, msg);
+	memset(&dp, 0, sizeof(dp));
+	osmo_prim_init(&dp.oph, 0, PRIM_DL_DATA, PRIM_OP_REQUEST, msg);
 
-        /* send to L2 */
-        lapd_recv_dlsap(&dp, &sap->dl.lctx);
+	/* send to L2 */
+	return lapd_recv_dlsap(&dp, &sap->dl.lctx);
 };
 
 static int send_ph_data_req(struct lapd_msg_ctx *lctx, struct msgb *msg)
@@ -368,15 +377,15 @@ static int send_ph_data_req(struct lapd_msg_ctx *lctx, struct msgb *msg)
 	}
 	/* address field */
 	msg->l2h = msgb_push(msg, 2);
-	msg->l2h[0] = LAPD_ADDR2(lctx->sapi, lctx->cr);
-	msg->l2h[1] = LAPD_ADDR3(lctx->tei);
+	msg->l2h[0] = LAPD_ADDR1(lctx->sapi, lctx->cr);
+	msg->l2h[1] = LAPD_ADDR2(lctx->tei);
 
 	/* write to PCAP file, if enabled. */
 	osmo_pcap_lapd_write(li->pcap_fd, OSMO_LAPD_PCAP_OUTPUT, msg);
 
 	/* forward frame to L1 */
 	LOGDL(dl, LOGL_DEBUG, "TX: %s\n", osmo_hexdump(msg->data, msg->len));
-	li->transmit_cb(msg, li->transmit_cbdata);
+	li->ph_data_req_cb(msg, li->ph_data_req_cbdata);
 
 	return 0;
 }
@@ -392,14 +401,14 @@ static int send_dlsap(struct osmo_dlsap_prim *dp, struct lapd_msg_ctx *lctx)
 
 	li = sap->li;
 
-	dladdr = lctx->tei << 8 | lctx->sapi;
+	dladdr = lctx->sapi << 7 | lctx->tei;
 
 	switch (dp->oph.primitive) {
 	case PRIM_DL_EST:
-		LOGDL(dl, LOGL_NOTICE, "LAPD DL-ESTABLISH %s DLADDR=%u\n", op, dladdr);
+		LOGDL(dl, LOGL_DEBUG, "LAPD DL-ESTABLISH %s DLADDR=%u\n", op, dladdr);
 		break;
 	case PRIM_DL_REL:
-		LOGDL(dl, LOGL_NOTICE, "LAPD DL-RELEASE %s DLADDR=%u\n", op, dladdr);
+		LOGDL(dl, LOGL_DEBUG, "LAPD DL-RELEASE %s DLADDR=%u\n", op, dladdr);
 		lapv5_sap_free(sap);
 		/* note: sap and dl is now gone, don't use it anymore */
 		break;
@@ -407,15 +416,15 @@ static int send_dlsap(struct osmo_dlsap_prim *dp, struct lapd_msg_ctx *lctx)
 		;
 	}
 
-	li->receive_cb(dp, dladdr, li->receive_cbdata);
+	li->dl_receive_cb(dp, dladdr, li->dl_receive_cbdata);
 
 	return 0;
 }
 
 /* Allocate a new LAPV5 instance */
 struct lapv5_instance *lapv5_instance_alloc(int network_side,
-	void (*tx_cb)(struct msgb *msg, void *cbdata), void *tx_cbdata,
-	void (*rx_cb)(struct osmo_dlsap_prim *odp, uint16_t dladdr, void *rx_cbdata), void *rx_cbdata,
+	int (*ph_data_req_cb)(struct msgb *msg, void *cbdata), void *ph_data_req_cbdata,
+	int (*dl_receive_cb)(struct osmo_dlsap_prim *odp, uint16_t dladdr, void *rx_cbdata), void *dl_receive_cbdata,
 	const struct lapd_profile *profile, const char *name)
 {
 	struct lapv5_instance *li;
@@ -425,10 +434,10 @@ struct lapv5_instance *lapv5_instance_alloc(int network_side,
 		return NULL;
 
 	li->network_side = network_side;
-	li->transmit_cb = tx_cb;
-	li->transmit_cbdata = tx_cbdata;
-	li->receive_cb = rx_cb;
-	li->receive_cbdata = rx_cbdata;
+	li->ph_data_req_cb = ph_data_req_cb;
+	li->ph_data_req_cbdata = ph_data_req_cbdata;
+	li->dl_receive_cb = dl_receive_cb;
+	li->dl_receive_cbdata = dl_receive_cbdata;
 	li->pcap_fd = -1;
 	li->name = talloc_strdup(li, name);
 	memcpy(&li->profile, profile, sizeof(li->profile));
@@ -470,62 +479,121 @@ void lapv5_instance_free(struct lapv5_instance *li)
  * while the last octet (before msg->tail) points to the last FCS octet. */
 int lapv5ef_rx(struct v5x_link *link, struct msgb *msg)
 {
-	struct lapd_datalink *dl;
+	struct lapv5_instance *li = NULL;
+	struct v5x_user_port *v5up = NULL;
 	uint16_t efaddr, efaddr_enc;
 	bool is_isdn;
+	int error;
 
 	msg->l1h = msg->data;
 
 	if (msgb_length(msg) < 2) {
+		LOGP(DV5EF, LOGL_ERROR, "Frame too short.\n");
 		msgb_free(msg);
 		return -EINVAL;
 	}
 
-	msg->l2h = msg->l1h + 2;
-	efaddr_enc = msg->l1h[0] << 8 | msg->l1h[1];
-	efaddr = v51_l3_addr_dec(efaddr_enc, &is_isdn);
+	efaddr_enc = msg->l2h[0] << 8 | msg->l2h[1];
+	msg->l2h += 2;
+	msgb_pull(msg, msg->l2h - msg->data);
+	efaddr = v5x_l3_addr_dec(efaddr_enc, &is_isdn);
+
 
 	if (!is_isdn) {
-		/* EFaddr are structured like isdn-type L3 Address */
+		LOGP(DV5EF, LOGL_ERROR, "EFaddr are structured like isdn-type L3 Address.\n");
 		msgb_free(msg);
 		return -EINVAL;
 	}
 
 	switch (efaddr) {
-	case V51_DLADDR_PSTN:
+	case V5X_DLADDR_PSTN:
 		/* hand-over to LAPD-DL instance for PSTN */
-		dl = &link->interface->pstn.dl;
-		/* TODO */
+		li = link->interface->pstn.li;
 		break;
-	case V51_DLADDR_CTRL:
+	case V5X_DLADDR_CTRL:
 		/* hand-over to LAPD-DL instance for CTRL */
-		/* TODO */
-		dl = &link->interface->control.dl;
+		li = link->interface->control.li;
 		break;
 	case V52_DLADDR_BCC:
-		dl = &link->interface->bcc.dl;
-		/* TOOD: implement V5.2 */
-		msgb_free(msg);
+		/* hand-over to LAPD-DL instance for BCC */
+		li = link->interface->bcc.li;
 		break;
 	case V52_DLADDR_PROTECTION:
-		dl = &link->interface->protection[0].dl;
-		/* TOOD: implement V5.2 */
-		msgb_free(msg);
+		/* hand-over to LAPD-DL instance for PROTECTION */
+		if (link == link->interface->primary_link)
+			li = link->interface->protection.li[0];
+		if (link == link->interface->secondary_link)
+			li = link->interface->protection.li[1];
 		break;
 	case V52_DLADDR_LCP:
-		dl = &link->interface->lcp.dl;
-		/* TOOD: implement V5.2 */
-		msgb_free(msg);
+		/* hand-over to LAPD-DL instance for LCP */
+		li = link->interface->lcp.li;
 		break;
 	default:
 		if (efaddr >= 8176) {
 			/* reserved as per Section 9.2.2.2 of G.964 */
+			LOGP(DV5EF, LOGL_ERROR, "No LAPV5 protocol for EFaddr %d.\n", efaddr);
 			msgb_free(msg);
 			return -EINVAL;
 		}
 		/* relay function for LAPD of user ports */
-		/* TODO */
+		v5up = v5x_user_port_find(link->interface, efaddr, true);
+		if (!v5up) {
+			LOGP(DV5EF, LOGL_ERROR, "No ISDN user port instance for EFaddr %d created.\n", efaddr);
+			msgb_free(msg);
+			return -EINVAL;
+		}
+		if (!v5x_le_port_isdn_is_operational(v5up->port_fi)) {
+			LOGP(DV5EF, LOGL_NOTICE, "Dropping D-channel (AN->LE) message of non-operational ISDN port for EFaddr %d.\n", efaddr);
+			msgb_free(msg);
+			return -EIO;
+		}
+		LOGP(DV5EF, LOGL_DEBUG, "Recevied frame for EFaddr %d: %s\n", efaddr, osmo_hexdump(msg->data, msg->len));
+		ph_socket_tx_msg(&v5up->ph_socket, 3, PH_PRIM_DATA_IND, msg->data, msg->len);
+		msgb_free(msg);
+		return 0;
+	}
+
+	if (!li) {
+		LOGP(DV5EF, LOGL_ERROR, "No LAPV5 instance for EFaddr %d created.\n", efaddr);
+		msgb_free(msg);
+		return -EINVAL;
 	}
 
+	lapv5_ph_data_ind(li, msg, &error);
+
 	return 0;
 }
+
+int lapv5ef_tx(struct v5x_user_port *v5up, struct msgb *msg)
+{
+	uint16_t efaddr = v5up->nr, efaddr_enc;
+
+	if (!v5x_le_port_isdn_is_operational(v5up->port_fi)) {
+		LOGP(DV5EF, LOGL_NOTICE, "Dropping D-channel (LE->AN) message of non-operational ISDN port for EFaddr %d.\n", efaddr);
+		msgb_free(msg);
+		return -EIO;
+	}
+	/* relay function for LAPD of user ports */
+	LOGP(DV5EF, LOGL_DEBUG, "Sending frame for EFaddr %d: %s\n", efaddr, osmo_hexdump(msg->data, msg->len));
+	msg->l2h = msgb_push(msg, 2);
+	efaddr_enc = v5x_l3_addr_enc(efaddr, 1);
+	msg->l2h[0] = efaddr_enc >> 8;
+	msg->l2h[1] = efaddr_enc;
+	ph_data_req_hdlc(msg, v5up->interface);
+
+	return 0;
+}
+
+/* set enabled state, also free all SAP, so it will disable/enable with a cleanly */
+void lapv5_set_enabled(struct lapv5_instance *li, bool enabled)
+{
+	struct lapv5_sap *sap;
+
+	li->enabled = enabled;
+
+	/* reset DL instances */
+	llist_for_each_entry(sap, &li->sap_list, list) {
+		lapd_dl_reset(&sap->dl);
+	}
+}

src/lapv5.h

@@ -0,0 +1,43 @@
+#pragma once
+
+#include <osmocom/abis/lapd.h>
+
+struct lapv5_instance {
+	struct llist_head list;		/* list of LAPV5 instances */
+	bool network_side;
+
+	int (*ph_data_req_cb)(struct msgb *msg, void *cbdata);
+	void *ph_data_req_cbdata;
+	int (*dl_receive_cb)(struct osmo_dlsap_prim *odp, uint16_t dladdr, void *rx_cbdata);
+	void *dl_receive_cbdata;
+
+	struct lapd_profile profile;	/* must be a copy */
+
+	struct llist_head sap_list;	/* list of SAP/datalinks in this instance */
+	int pcap_fd;			/* PCAP file descriptor */
+	char *name;			/* human-readable name */
+
+	bool enabled;			/* only receive messages when enabled */
+};
+
+extern const struct lapd_profile lapd_profile_lapv5dl;
+
+int lapv5ef_rx(struct v5x_link *link, struct msgb *msg);
+
+int lapv5_dl_est_req(struct lapv5_instance *li, uint16_t dladdr);
+int lapv5_dl_rel_req(struct lapv5_instance *li, uint16_t dladdr);
+int lapv5_dl_data_req(struct lapv5_instance *li, uint16_t dladdr, struct msgb *msg);
+
+int lapv5_ph_data_ind(struct lapv5_instance *li, struct msgb *msg, int *error);
+
+struct lapv5_instance *lapv5_instance_alloc(int network_side,
+	int (*ph_data_req_cb)(struct msgb *msg, void *cbdata), void *ph_data_req_cbdata,
+	int (*dl_receive_cb)(struct osmo_dlsap_prim *odp, uint16_t dladdr, void *rx_cbdata), void *dl_receive_cbdata,
+	const struct lapd_profile *profile, const char *name);
+void lapv5_instance_set_profile(struct lapv5_instance *li, const struct lapd_profile *profile);
+void lapv5_instance_free(struct lapv5_instance *li);
+
+int lapv5ef_rx(struct v5x_link *link, struct msgb *msg);
+int lapv5ef_tx(struct v5x_user_port *v5up, struct msgb *msg);
+
+void lapv5_set_enabled(struct lapv5_instance *li, bool enabled);

src/layer1.c

@@ -0,0 +1,537 @@
+
+#include <stdio.h>
+#include <errno.h>
+#include <osmocom/core/gsmtap.h>
+#include <osmocom/core/gsmtap_util.h>
+#include <osmocom/core/signal.h>
+
+#include "v5x_internal.h"
+#include "v5x_protocol.h"
+#include "lapv5.h"
+#include "layer1.h"
+#include "v5x_l1_fsm.h"
+#include "v5x_le_management.h"
+#include "logging.h"
+#include "libg711/g711.h"
+
+extern int ulaw;
+extern int test_sa7;
+extern const char *gsmtap_ip;
+
+extern struct v5x_instance *v5i;
+
+static struct gsmtap_inst *g_gti = NULL;
+
+/* only temporarily until this is in libosmocore gsmtap.h */
+#ifndef GSMTAP_E1T1_V5EF
+#define GSMTAP_E1T1_V5EF	0x06
+#endif
+
+/* Callback function to receive L1 signal from E1 port */
+static int inp_sig_cb(unsigned int subsys, unsigned int signal, void __attribute__((unused)) *handler_data,
+	void *signal_data)
+{
+	struct input_signal_data *isd = signal_data;
+	struct v5x_link *v5l;
+
+	if (subsys != SS_L_INPUT)
+		return 0;
+
+	/* not used by any link */
+	if (!isd->line->ops)
+		return 0;
+	v5l = container_of(isd->line->ops, struct v5x_link, e1_line_ops);
+
+	switch (signal) {
+	case S_L_INP_LINE_LOS:
+		v5x_l1_signal_rcv(v5l, L1_SIGNAL_LOS);
+		break;
+	case S_L_INP_LINE_NOLOS:
+		v5x_l1_signal_rcv(v5l, L1_SIGNAL_NO_LOS);
+		break;
+	case S_L_INP_LINE_RAI:
+		v5x_l1_signal_rcv(v5l, L1_SIGNAL_RAI);
+		break;
+	case S_L_INP_LINE_NORAI:
+		v5x_l1_signal_rcv(v5l, L1_SIGNAL_NO_RAI);
+		break;
+	case S_L_INP_LINE_AIS:
+		v5x_l1_signal_rcv(v5l, L1_SIGNAL_AIS);
+		break;
+	case S_L_INP_LINE_NOAIS:
+		v5x_l1_signal_rcv(v5l, L1_SIGNAL_NO_AIS);
+		break;
+	case S_L_INP_LINE_SA_BITS:
+		if ((isd->sa_bits & 0x40)) {
+			v5x_l1_signal_rcv(v5l, L1_SIGNAL_SA7_1);
+			if (test_sa7) {
+				printf("Currently Sa 7 is set to 1, changing it to 0. (Link ID %d)\n", v5l->id);
+				v5x_l1_signal_snd(v5l, L1_SIGNAL_SA7_0);
+			}
+		} else {
+			v5x_l1_signal_rcv(v5l, L1_SIGNAL_SA7_0);
+			if (test_sa7) {
+				printf("Currently Sa 7 is set to 0, changing it to 1. (Link ID %d)\n", v5l->id);
+				v5x_l1_signal_snd(v5l, L1_SIGNAL_SA7_1);
+			}
+		}
+		break;
+	case S_L_INP_LINE_SLIP_RX:
+		printf("RX slip detected on link %d.\n", v5l->id);
+		break;
+	case S_L_INP_LINE_SLIP_TX:
+		printf("TX slip detected on link %d.\n", v5l->id);
+		break;
+	default:
+		;
+	}
+
+	return 0;
+}
+
+/* Send L1 signal to E1 port */
+int v5x_l1_signal_snd(struct v5x_link *v5l, enum l1_signal_prim prim)
+{
+	struct e1inp_line *e1_line = v5l->e1_line;
+
+	/* no line assigned */
+	if (!e1_line)
+		return 0;
+
+	switch (prim) {
+	case L1_SIGNAL_SA7_0:
+		e1inp_ts_set_sa_bits(e1_line, 0xbf);
+		break;
+	case L1_SIGNAL_SA7_1:
+		e1inp_ts_set_sa_bits(e1_line, 0xff);
+		break;
+	default:
+		;
+	}
+
+	return 0;
+}
+
+/* store TX to buffer */
+static void echo_tx(struct v5x_echo_proc *ep, uint8_t *data, int len)
+{
+	int in;
+	int16_t tx;
+
+	if (!ep->enabled)
+		return;
+
+	while (len--) {
+		if (ulaw)
+			tx = g711_ulaw_flipped_to_linear[*data++];
+		else
+			tx = g711_alaw_flipped_to_linear[*data++];
+		ep->tx_buffer[ep->tx_buffer_in] = tx;
+		in = (ep->tx_buffer_in + 1) % EC_BUFFER;
+		/* buffer overflow condition, should not happen, if application syncs to RX */
+		if (in == ep->tx_buffer_out)
+			break;
+		ep->tx_buffer_in = in;
+	}
+}
+
+/* remove echo from RX using TX from buffer */
+static void echo_rx(struct v5x_echo_proc *ep, uint8_t *data, int len)
+{
+	struct v5x_user_port *v5up = ep->port;
+	int16_t tx, rx, rx_can;
+	int16_t answer_buffer[len];
+	int i;
+	int rc;
+
+	if (!ep->enabled)
+		return;
+
+	for (i = 0; i < len; i++) {
+		/* buffer underrun condition, may happen before buffer was filled with first frame */
+		if (ep->tx_buffer_out == ep->tx_buffer_in)
+			tx = 0;
+		else {
+			tx = ep->tx_buffer[ep->tx_buffer_out];
+			ep->tx_buffer_out = (ep->tx_buffer_out + 1) % EC_BUFFER;
+		}
+		if (ulaw) {
+			rx = g711_ulaw_flipped_to_linear[*data];
+			if (ep->port->use_line_echo == USE_ECHO_CANCELER)
+				rx_can = echo_can_update(ep->ec, tx, rx);
+			else
+				rx_can = echo_sup_update(ep->es, tx, rx);
+			*data++ = g711_linear_to_ulaw_flipped[(uint16_t)rx_can];
+		} else {
+			rx = g711_alaw_flipped_to_linear[*data];
+			if (ep->port->use_line_echo == USE_ECHO_CANCELER)
+				rx_can = echo_can_update(ep->ec, tx, rx);
+			else
+				rx_can = echo_sup_update(ep->es, tx, rx);
+			*data++ = g711_linear_to_alaw_flipped[(uint16_t)rx_can];
+		}
+		answer_buffer[i] = rx + tx; /* yes, may overflow, but then it is no valid tone anyway */
+	}
+
+	rc = answertone_process(&ep->at, answer_buffer, len, (ep->port->use_line_echo == USE_ECHO_CANCELER));
+	if (rc > 0) {
+		LOGP(DV5, LOGL_NOTICE, "Detected answer tone, disable echo %s of %s port %d.\n",
+			(ep->port->use_line_echo == USE_ECHO_CANCELER) ? "canceler" : "suppressor",
+			(v5up->type == V5X_USER_TYPE_PSTN) ? "PSTN" : "ISDN", v5up->nr);
+		ep->enabled = 0;
+	}
+}
+
+/* data L1 -> L2 from E1 interface */
+static void hdlc_rx_cb(struct e1inp_ts *ts, struct msgb *msg)
+{
+	struct v5x_link *v5l;
+
+	/* not used by any link */
+	if (!ts->line->ops) {
+		msgb_free(msg);
+		return;
+	}
+	v5l = container_of(ts->line->ops, struct v5x_link, e1_line_ops);
+
+	LOGP(DLINP, LOGL_DEBUG, "Link %d L1->L2: %s\n", v5l->id, msgb_hexdump(msg));
+
+	/* send V5 data via gsmtap so wireshark can receive + decode it */
+	if (g_gti) {
+		gsmtap_send_ex(g_gti, GSMTAP_TYPE_E1T1, v5l->id, ts->num, GSMTAP_E1T1_V5EF,
+				0, 0, 0, 0, msgb_data(msg), msgb_length(msg));
+	}
+
+	lapv5ef_rx(v5l, msg);
+}
+
+/* data B-channel data from E1 interface */
+static void raw_rx_cb(struct e1inp_ts *ts, struct msgb *msg)
+{
+	struct v5x_link *v5l;
+	struct v5x_user_port *v5up;
+
+	/* not used by any link */
+	if (!ts->line->ops) {
+		msgb_free(msg);
+		return;
+	}
+	v5l = container_of(ts->line->ops, struct v5x_link, e1_line_ops);
+	v5up = v5l->ts[ts->num].v5up;
+
+	/* not used by any user port */
+	if (!v5up) {
+		msgb_free(msg);
+		return;
+	}
+
+	/* we want B-channel data flipped */
+	osmo_revbytebits_buf(msg->data, msg->len);
+				
+	/* if assigned and active, send B-channel data to socket interface */
+	if (v5up->ts[0] && v5up->ts[0]->nr == ts->num && v5up->ts[0]->b_activated) {
+		echo_rx(&v5up->ep[0], msg->data, msg->len);
+		ph_socket_tx_msg(&v5up->ph_socket, 1, PH_PRIM_DATA_IND, msg->data, msg->len);
+	}
+	if (v5up->ts[1] && v5up->ts[1]->nr == ts->num && v5up->ts[1]->b_activated) {
+		echo_rx(&v5up->ep[1], msg->data, msg->len);
+		ph_socket_tx_msg(&v5up->ph_socket, 2, PH_PRIM_DATA_IND, msg->data, msg->len);
+	}
+	msgb_free(msg);
+}
+
+/* send HDLC frame to signaling channel (from ISDN) */
+int ph_data_req_hdlc(struct msgb *msg, struct v5x_interface *v5if)
+{
+	struct e1inp_line *e1_line = v5if->cc_link->e1_line;
+
+	if (!e1_line) {
+		msgb_free(msg);
+		return 0;
+	}
+
+	if (!v5x_l1_is_up(v5if->cc_link->l1)) {
+		LOGP(DLINP, LOGL_DEBUG, "Link %d is down!\n", v5if->cc_link->id);
+		msgb_free(msg);
+		return 0;
+	}
+
+	LOGP(DLINP, LOGL_DEBUG, "Link %d L2->L1: %s\n", v5if->cc_link->id, msgb_hexdump(msg));
+
+	struct e1inp_ts *ts = &e1_line->ts[v5if->cc_link->c_channel[0].ts->nr - 1];
+
+	/* send V5 data via gsmtap so wireshark can receive + decode it */
+	if (g_gti) {
+		gsmtap_send_ex(g_gti, GSMTAP_TYPE_E1T1, v5if->cc_link->id | GSMTAP_ARFCN_F_UPLINK, ts->num,
+				GSMTAP_E1T1_V5EF, 0, 0, 0, 0, msgb_data(msg), msgb_length(msg));
+	}
+
+	return e1inp_ts_send_hdlc(ts, msg);
+}
+
+/* send HDLC frame to signaling channel (from DL) */
+int ph_data_req_dl_cc(struct msgb *msg, void *cbdata)
+{
+	struct v5x_interface *v5if = (struct v5x_interface *)cbdata;
+	struct e1inp_line *e1_line = v5if->cc_link->e1_line;
+
+	if (!e1_line) {
+		msgb_free(msg);
+		return 0;
+	}
+
+	if (!v5x_l1_is_up(v5if->cc_link->l1)) {
+		LOGP(DLINP, LOGL_DEBUG, "Link %d is down!\n", v5if->cc_link->id);
+		msgb_free(msg);
+		return 0;