Adding upstream version 8.4.4.upstream/8.4.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

12 files changed, 3011 insertions, 0 deletions

diff --git a/ospfclient/.gitignore b/ospfclient/.gitignore
new file mode 100644
index 0000000..9be7045
--- /dev/null
+++ b/ospfclient/.gitignore
@@ -0,0 +1 @@
+ospfclient
diff --git a/ospfclient/AUTHORS b/ospfclient/AUTHORS
new file mode 100644
index 0000000..b865c55
--- /dev/null
+++ b/ospfclient/AUTHORS
@@ -0,0 +1 @@
+Ralph Keller <keller@tik.ee.ethz.ch>
diff --git a/ospfclient/COPYING b/ospfclient/COPYING
new file mode 100644
index 0000000..b8cf3a1
--- /dev/null
+++ b/ospfclient/COPYING
@@ -0,0 +1,339 @@
+		    GNU GENERAL PUBLIC LICENSE
+		       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+                          675 Mass Ave, Cambridge, MA 02139, USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+			    Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
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+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
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+(2) offer you this license which gives you legal permission to copy,
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+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
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+Activities other than copying, distribution and modification are not
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+running the Program is not restricted, and the output from the Program
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+You may charge a fee for the physical act of transferring a copy, and
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+This section is intended to make thoroughly clear what is believed to
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+Foundation.
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+
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+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
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+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
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+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
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+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
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+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
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+
+		     END OF TERMS AND CONDITIONS
+
+	Appendix: How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) 19yy  <name of author>
+
+    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 2 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, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) 19yy name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.
diff --git a/ospfclient/INSTALL b/ospfclient/INSTALL
new file mode 100644
index 0000000..b42a17a
--- /dev/null
+++ b/ospfclient/INSTALL
@@ -0,0 +1,182 @@
+Basic Installation
+==================
+
+   These are generic installation instructions.
+
+   The `configure' shell script attempts to guess correct values for
+various system-dependent variables used during compilation.  It uses
+those values to create a `Makefile' in each directory of the package.
+It may also create one or more `.h' files containing system-dependent
+definitions.  Finally, it creates a shell script `config.status' that
+you can run in the future to recreate the current configuration, a file
+`config.cache' that saves the results of its tests to speed up
+reconfiguring, and a file `config.log' containing compiler output
+(useful mainly for debugging `configure').
+
+   If you need to do unusual things to compile the package, please try
+to figure out how `configure' could check whether to do them, and mail
+diffs or instructions to the address given in the `README' so they can
+be considered for the next release.  If at some point `config.cache'
+contains results you don't want to keep, you may remove or edit it.
+
+   The file `configure.in' is used to create `configure' by a program
+called `autoconf'.  You only need `configure.in' if you want to change
+it or regenerate `configure' using a newer version of `autoconf'.
+
+The simplest way to compile this package is:
+
+  1. `cd' to the directory containing the package's source code and type
+     `./configure' to configure the package for your system.  If you're
+     using `csh' on an old version of System V, you might need to type
+     `sh ./configure' instead to prevent `csh' from trying to execute
+     `configure' itself.
+
+     Running `configure' takes awhile.  While running, it prints some
+     messages telling which features it is checking for.
+
+  2. Type `make' to compile the package.
+
+  3. Optionally, type `make check' to run any self-tests that come with
+     the package.
+
+  4. Type `make install' to install the programs and any data files and
+     documentation.
+
+  5. You can remove the program binaries and object files from the
+     source code directory by typing `make clean'.  To also remove the
+     files that `configure' created (so you can compile the package for
+     a different kind of computer), type `make distclean'.  There is
+     also a `make maintainer-clean' target, but that is intended mainly
+     for the package's developers.  If you use it, you may have to get
+     all sorts of other programs in order to regenerate files that came
+     with the distribution.
+
+Compilers and Options
+=====================
+
+   Some systems require unusual options for compilation or linking that
+the `configure' script does not know about.  You can give `configure'
+initial values for variables by setting them in the environment.  Using
+a Bourne-compatible shell, you can do that on the command line like
+this:
+     CC=c89 CFLAGS=-O2 LIBS=-lposix ./configure
+
+Or on systems that have the `env' program, you can do it like this:
+     env CPPFLAGS=-I/usr/local/include LDFLAGS=-s ./configure
+
+Compiling For Multiple Architectures
+====================================
+
+   You can compile the package for more than one kind of computer at the
+same time, by placing the object files for each architecture in their
+own directory.  To do this, you must use a version of `make' that
+supports the `VPATH' variable, such as GNU `make'.  `cd' to the
+directory where you want the object files and executables to go and run
+the `configure' script.  `configure' automatically checks for the
+source code in the directory that `configure' is in and in `..'.
+
+   If you have to use a `make' that does not supports the `VPATH'
+variable, you have to compile the package for one architecture at a time
+in the source code directory.  After you have installed the package for
+one architecture, use `make distclean' before reconfiguring for another
+architecture.
+
+Installation Names
+==================
+
+   By default, `make install' will install the package's files in
+`/usr/local/bin', `/usr/local/man', etc.  You can specify an
+installation prefix other than `/usr/local' by giving `configure' the
+option `--prefix=PATH'.
+
+   You can specify separate installation prefixes for
+architecture-specific files and architecture-independent files.  If you
+give `configure' the option `--exec-prefix=PATH', the package will use
+PATH as the prefix for installing programs and libraries.
+Documentation and other data files will still use the regular prefix.
+
+   In addition, if you use an unusual directory layout you can give
+options like `--bindir=PATH' to specify different values for particular
+kinds of files.  Run `configure --help' for a list of the directories
+you can set and what kinds of files go in them.
+
+   If the package supports it, you can cause programs to be installed
+with an extra prefix or suffix on their names by giving `configure' the
+option `--program-prefix=PREFIX' or `--program-suffix=SUFFIX'.
+
+Optional Features
+=================
+
+   Some packages pay attention to `--enable-FEATURE' options to
+`configure', where FEATURE indicates an optional part of the package.
+They may also pay attention to `--with-PACKAGE' options, where PACKAGE
+is something like `gnu-as' or `x' (for the X Window System).  The
+`README' should mention any `--enable-' and `--with-' options that the
+package recognizes.
+
+   For packages that use the X Window System, `configure' can usually
+find the X include and library files automatically, but if it doesn't,
+you can use the `configure' options `--x-includes=DIR' and
+`--x-libraries=DIR' to specify their locations.
+
+Specifying the System Type
+==========================
+
+   There may be some features `configure' can not figure out
+automatically, but needs to determine by the type of host the package
+will run on.  Usually `configure' can figure that out, but if it prints
+a message saying it can not guess the host type, give it the
+`--host=TYPE' option.  TYPE can either be a short name for the system
+type, such as `sun4', or a canonical name with three fields:
+     CPU-COMPANY-SYSTEM
+
+See the file `config.sub' for the possible values of each field.  If
+`config.sub' isn't included in this package, then this package doesn't
+need to know the host type.
+
+   If you are building compiler tools for cross-compiling, you can also
+use the `--target=TYPE' option to select the type of system they will
+produce code for and the `--build=TYPE' option to select the type of
+system on which you are compiling the package.
+
+Sharing Defaults
+================
+
+   If you want to set default values for `configure' scripts to share,
+you can create a site shell script called `config.site' that gives
+default values for variables like `CC', `cache_file', and `prefix'.
+`configure' looks for `PREFIX/share/config.site' if it exists, then
+`PREFIX/etc/config.site' if it exists.  Or, you can set the
+`CONFIG_SITE' environment variable to the location of the site script.
+A warning: not all `configure' scripts look for a site script.
+
+Operation Controls
+==================
+
+   `configure' recognizes the following options to control how it
+operates.
+
+`--cache-file=FILE'
+     Use and save the results of the tests in FILE instead of
+     `./config.cache'.  Set FILE to `/dev/null' to disable caching, for
+     debugging `configure'.
+
+`--help'
+     Print a summary of the options to `configure', and exit.
+
+`--quiet'
+`--silent'
+`-q'
+     Do not print messages saying which checks are being made.  To
+     suppress all normal output, redirect it to `/dev/null' (any error
+     messages will still be shown).
+
+`--srcdir=DIR'
+     Look for the package's source code in directory DIR.  Usually
+     `configure' can determine that directory automatically.
+
+`--version'
+     Print the version of Autoconf used to generate the `configure'
+     script, and exit.
+
+`configure' also accepts some other, not widely useful, options.
diff --git a/ospfclient/Makefile b/ospfclient/Makefile
new file mode 100644
index 0000000..3da2a5b
--- /dev/null
+++ b/ospfclient/Makefile
@@ -0,0 +1,10 @@
+all: ALWAYS
+	@$(MAKE) -s -C .. ospfclient/ospfclient
+%: ALWAYS
+	@$(MAKE) -s -C .. ospfclient/$@
+
+Makefile:
+	#nothing
+ALWAYS:
+.PHONY: ALWAYS makefiles
+.SUFFIXES:
diff --git a/ospfclient/NEWS b/ospfclient/NEWS
new file mode 100644
index 0000000..5b1ec4f
--- /dev/null
+++ b/ospfclient/NEWS
@@ -0,0 +1 @@
+This file contains news.
diff --git a/ospfclient/README b/ospfclient/README
new file mode 100644
index 0000000..5f6d050
--- /dev/null
+++ b/ospfclient/README
@@ -0,0 +1,3 @@
+For more information checkout the developer guide at:
+
+https://docs.frrouting.org/projects/dev-guide/en/latest/ospf-api.html
diff --git a/ospfclient/ospf_apiclient.c b/ospfclient/ospf_apiclient.c
new file mode 100644
index 0000000..2a125f0
--- /dev/null
+++ b/ospfclient/ospf_apiclient.c
@@ -0,0 +1,736 @@
+/*
+ * Client side of OSPF API.
+ * Copyright (C) 2001, 2002, 2003 Ralph Keller
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra 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 2, or (at your
+ * option) any later version.
+ *
+ * GNU Zebra 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; see the file COPYING; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <zebra.h>
+
+#include <lib/version.h>
+#include "getopt.h"
+#include "thread.h"
+#include "prefix.h"
+#include "linklist.h"
+#include "if.h"
+#include "vector.h"
+#include "vty.h"
+#include "command.h"
+#include "filter.h"
+#include "stream.h"
+#include "log.h"
+#include "memory.h"
+#include "xref.h"
+
+/* work around gcc bug 69981, disable MTYPEs in libospf */
+#define _QUAGGA_OSPF_MEMORY_H
+
+#include "ospfd/ospfd.h"
+#include "ospfd/ospf_interface.h"
+#include "ospfd/ospf_asbr.h"
+#include "ospfd/ospf_lsa.h"
+#include "ospfd/ospf_opaque.h"
+#include "ospfd/ospf_lsdb.h"
+#include "ospfd/ospf_neighbor.h"
+#include "ospfd/ospf_dump.h"
+#include "ospfd/ospf_route.h"
+#include "ospfd/ospf_zebra.h"
+#include "ospfd/ospf_api.h"
+#include "ospfd/ospf_errors.h"
+
+#include "ospf_apiclient.h"
+
+XREF_SETUP();
+
+DEFINE_MGROUP(OSPFCLIENT, "libospfapiclient");
+DEFINE_MTYPE_STATIC(OSPFCLIENT, OSPF_APICLIENT, "OSPF-API client");
+
+/* Backlog for listen */
+#define BACKLOG 5
+
+/* -----------------------------------------------------------
+ * Forward declarations
+ * -----------------------------------------------------------
+ */
+
+void ospf_apiclient_handle_reply(struct ospf_apiclient *oclient,
+				 struct msg *msg);
+void ospf_apiclient_handle_update_notify(struct ospf_apiclient *oclient,
+					 struct msg *msg);
+void ospf_apiclient_handle_delete_notify(struct ospf_apiclient *oclient,
+					 struct msg *msg);
+
+/* -----------------------------------------------------------
+ * Initialization
+ * -----------------------------------------------------------
+ */
+
+static unsigned short ospf_apiclient_getport(void)
+{
+	struct servent *sp = getservbyname("ospfapi", "tcp");
+
+	return sp ? ntohs(sp->s_port) : OSPF_API_SYNC_PORT;
+}
+
+/* -----------------------------------------------------------
+ * Following are functions for connection management
+ * -----------------------------------------------------------
+ */
+
+struct ospf_apiclient *ospf_apiclient_connect(char *host, int syncport)
+{
+	struct sockaddr_in myaddr_sync;
+	struct sockaddr_in myaddr_async;
+	struct sockaddr_in peeraddr;
+	struct hostent *hp;
+	struct ospf_apiclient *new;
+	int size = 0;
+	unsigned int peeraddrlen;
+	int async_server_sock;
+	int fd1, fd2;
+	int ret;
+	int on = 1;
+
+	/* There are two connections between the client and the server.
+	   First the client opens a connection for synchronous requests/replies
+	   to the server. The server will accept this connection and
+	   as a reaction open a reverse connection channel for
+	   asynchronous messages. */
+
+	async_server_sock = socket(AF_INET, SOCK_STREAM, 0);
+	if (async_server_sock < 0) {
+		fprintf(stderr,
+			"ospf_apiclient_connect: creating async socket failed\n");
+		return NULL;
+	}
+
+	/* Prepare socket for asynchronous messages */
+	/* Initialize async address structure */
+	memset(&myaddr_async, 0, sizeof(myaddr_async));
+	myaddr_async.sin_family = AF_INET;
+	myaddr_async.sin_addr.s_addr = htonl(INADDR_ANY);
+	myaddr_async.sin_port = htons(syncport + 1);
+	size = sizeof(struct sockaddr_in);
+#ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
+	myaddr_async.sin_len = size;
+#endif /* HAVE_STRUCT_SOCKADDR_IN_SIN_LEN */
+
+	/* This is a server socket, reuse addr and port */
+	ret = setsockopt(async_server_sock, SOL_SOCKET, SO_REUSEADDR,
+			 (void *)&on, sizeof(on));
+	if (ret < 0) {
+		fprintf(stderr,
+			"ospf_apiclient_connect: SO_REUSEADDR failed\n");
+		close(async_server_sock);
+		return NULL;
+	}
+
+#ifdef SO_REUSEPORT
+	ret = setsockopt(async_server_sock, SOL_SOCKET, SO_REUSEPORT,
+			 (void *)&on, sizeof(on));
+	if (ret < 0) {
+		fprintf(stderr,
+			"ospf_apiclient_connect: SO_REUSEPORT failed\n");
+		close(async_server_sock);
+		return NULL;
+	}
+#endif /* SO_REUSEPORT */
+
+	/* Bind socket to address structure */
+	ret = bind(async_server_sock, (struct sockaddr *)&myaddr_async, size);
+	if (ret < 0) {
+		fprintf(stderr,
+			"ospf_apiclient_connect: bind async socket failed\n");
+		close(async_server_sock);
+		return NULL;
+	}
+
+	/* Wait for reverse channel connection establishment from server */
+	ret = listen(async_server_sock, BACKLOG);
+	if (ret < 0) {
+		fprintf(stderr, "ospf_apiclient_connect: listen: %s\n",
+			safe_strerror(errno));
+		close(async_server_sock);
+		return NULL;
+	}
+
+	/* Make connection for synchronous requests and connect to server */
+	/* Resolve address of server */
+	hp = gethostbyname(host);
+	if (!hp) {
+		fprintf(stderr, "ospf_apiclient_connect: no such host %s\n",
+			host);
+		close(async_server_sock);
+		return NULL;
+	}
+
+	fd1 = socket(AF_INET, SOCK_STREAM, 0);
+	if (fd1 < 0) {
+		close(async_server_sock);
+		fprintf(stderr,
+			"ospf_apiclient_connect: creating sync socket failed\n");
+		return NULL;
+	}
+
+
+	/* Reuse addr and port */
+	ret = setsockopt(fd1, SOL_SOCKET, SO_REUSEADDR, (void *)&on,
+			 sizeof(on));
+	if (ret < 0) {
+		fprintf(stderr,
+			"ospf_apiclient_connect: SO_REUSEADDR failed\n");
+		close(fd1);
+		close(async_server_sock);
+		return NULL;
+	}
+
+#ifdef SO_REUSEPORT
+	ret = setsockopt(fd1, SOL_SOCKET, SO_REUSEPORT, (void *)&on,
+			 sizeof(on));
+	if (ret < 0) {
+		fprintf(stderr,
+			"ospf_apiclient_connect: SO_REUSEPORT failed\n");
+		close(fd1);
+		close(async_server_sock);
+		return NULL;
+	}
+#endif /* SO_REUSEPORT */
+
+
+	/* Bind sync socket to address structure. This is needed since we
+	   want the sync port number on a fixed port number. The reverse
+	   async channel will be at this port+1 */
+
+	memset(&myaddr_sync, 0, sizeof(myaddr_sync));
+	myaddr_sync.sin_family = AF_INET;
+	myaddr_sync.sin_port = htons(syncport);
+#ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
+	myaddr_sync.sin_len = sizeof(struct sockaddr_in);
+#endif /* HAVE_STRUCT_SOCKADDR_IN_SIN_LEN */
+
+	ret = bind(fd1, (struct sockaddr *)&myaddr_sync, size);
+	if (ret < 0) {
+		fprintf(stderr,
+			"ospf_apiclient_connect: bind sync socket failed\n");
+		close(fd1);
+		close(async_server_sock);
+		return NULL;
+	}
+
+	/* Prepare address structure for connect */
+	memcpy(&myaddr_sync.sin_addr, hp->h_addr, hp->h_length);
+	myaddr_sync.sin_family = AF_INET;
+	myaddr_sync.sin_port = htons(ospf_apiclient_getport());
+#ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
+	myaddr_sync.sin_len = sizeof(struct sockaddr_in);
+#endif /* HAVE_STRUCT_SOCKADDR_IN_SIN_LEN */
+
+	/* Now establish synchronous channel with OSPF daemon */
+	ret = connect(fd1, (struct sockaddr *)&myaddr_sync,
+		      sizeof(struct sockaddr_in));
+	if (ret < 0) {
+		fprintf(stderr,
+			"ospf_apiclient_connect: sync connect failed\n");
+		close(async_server_sock);
+		close(fd1);
+		return NULL;
+	}
+
+	/* Accept reverse connection */
+	peeraddrlen = sizeof(struct sockaddr_in);
+	memset(&peeraddr, 0, peeraddrlen);
+
+	fd2 = accept(async_server_sock, (struct sockaddr *)&peeraddr,
+		     &peeraddrlen);
+	if (fd2 < 0) {
+		fprintf(stderr,
+			"ospf_apiclient_connect: accept async failed\n");
+		close(async_server_sock);
+		close(fd1);
+		close(fd2);
+		return NULL;
+	}
+
+	/* Server socket is not needed anymore since we are not accepting more
+	   connections */
+	close(async_server_sock);
+
+	/* Create new client-side instance */
+	new = XCALLOC(MTYPE_OSPF_APICLIENT, sizeof(struct ospf_apiclient));
+
+	/* Initialize socket descriptors for sync and async channels */
+	new->fd_sync = fd1;
+	new->fd_async = fd2;
+
+	return new;
+}
+
+int ospf_apiclient_close(struct ospf_apiclient *oclient)
+{
+
+	if (oclient->fd_sync >= 0) {
+		close(oclient->fd_sync);
+	}
+
+	if (oclient->fd_async >= 0) {
+		close(oclient->fd_async);
+	}
+
+	/* Free client structure */
+	XFREE(MTYPE_OSPF_APICLIENT, oclient);
+	return 0;
+}
+
+/* -----------------------------------------------------------
+ * Following are functions to send a request to OSPFd
+ * -----------------------------------------------------------
+ */
+
+/* Send synchronous request, wait for reply */
+static int ospf_apiclient_send_request(struct ospf_apiclient *oclient,
+				       struct msg *msg)
+{
+	uint32_t reqseq;
+	struct msg_reply *msgreply;
+	int rc;
+
+	/* NB: Given "msg" is freed inside this function. */
+
+	/* Remember the sequence number of the request */
+	reqseq = ntohl(msg->hdr.msgseq);
+
+	/* Write message to OSPFd */
+	rc = msg_write(oclient->fd_sync, msg);
+	msg_free(msg);
+
+	if (rc < 0) {
+		return -1;
+	}
+
+	/* Wait for reply */ /* NB: New "msg" is allocated by "msg_read()". */
+	msg = msg_read(oclient->fd_sync);
+	if (!msg)
+		return -1;
+
+	assert(msg->hdr.msgtype == MSG_REPLY);
+	assert(ntohl(msg->hdr.msgseq) == reqseq);
+
+	msgreply = (struct msg_reply *)STREAM_DATA(msg->s);
+	rc = msgreply->errcode;
+	msg_free(msg);
+
+	return rc;
+}
+
+
+/* -----------------------------------------------------------
+ * Helper functions
+ * -----------------------------------------------------------
+ */
+
+static uint32_t ospf_apiclient_get_seqnr(void)
+{
+	static uint32_t seqnr = MIN_SEQ;
+	uint32_t tmp;
+
+	tmp = seqnr;
+	/* Increment sequence number */
+	if (seqnr < MAX_SEQ) {
+		seqnr++;
+	} else {
+		seqnr = MIN_SEQ;
+	}
+	return tmp;
+}
+
+/* -----------------------------------------------------------
+ * API to access OSPF daemon by client applications.
+ * -----------------------------------------------------------
+ */
+
+/*
+ * Synchronous request to register opaque type.
+ */
+int ospf_apiclient_register_opaque_type(struct ospf_apiclient *cl,
+					uint8_t ltype, uint8_t otype)
+{
+	struct msg *msg;
+	int rc;
+
+	/* just put 1 as a sequence number. */
+	msg = new_msg_register_opaque_type(ospf_apiclient_get_seqnr(), ltype,
+					   otype);
+	if (!msg) {
+		fprintf(stderr, "new_msg_register_opaque_type failed\n");
+		return -1;
+	}
+
+	rc = ospf_apiclient_send_request(cl, msg);
+	return rc;
+}
+
+/*
+ * Synchronous request to synchronize with OSPF's LSDB.
+ * Two steps required: register_event in order to get
+ * dynamic updates and LSDB_Sync.
+ */
+int ospf_apiclient_sync_lsdb(struct ospf_apiclient *oclient)
+{
+	struct msg *msg;
+	int rc;
+	struct lsa_filter_type filter;
+
+	filter.typemask = 0xFFFF; /* all LSAs */
+	filter.origin = ANY_ORIGIN;
+	filter.num_areas = 0; /* all Areas. */
+
+	msg = new_msg_register_event(ospf_apiclient_get_seqnr(), &filter);
+	if (!msg) {
+		fprintf(stderr, "new_msg_register_event failed\n");
+		return -1;
+	}
+	rc = ospf_apiclient_send_request(oclient, msg);
+
+	if (rc != 0)
+		goto out;
+
+	msg = new_msg_sync_lsdb(ospf_apiclient_get_seqnr(), &filter);
+	if (!msg) {
+		fprintf(stderr, "new_msg_sync_lsdb failed\n");
+		return -1;
+	}
+	rc = ospf_apiclient_send_request(oclient, msg);
+
+out:
+	return rc;
+}
+
+/*
+ * Synchronous request to originate or update an LSA.
+ */
+
+int ospf_apiclient_lsa_originate(struct ospf_apiclient *oclient,
+				 struct in_addr ifaddr, struct in_addr area_id,
+				 uint8_t lsa_type, uint8_t opaque_type,
+				 uint32_t opaque_id, void *opaquedata,
+				 int opaquelen)
+{
+	struct msg *msg;
+	int rc;
+	uint8_t buf[OSPF_MAX_LSA_SIZE];
+	struct lsa_header *lsah;
+	uint32_t tmp;
+
+	/* Validate opaque LSA length */
+	if ((size_t)opaquelen > sizeof(buf) - sizeof(struct lsa_header)) {
+		fprintf(stderr, "opaquelen(%d) is larger than buf size %zu\n",
+			opaquelen, sizeof(buf));
+		return OSPF_API_NOMEMORY;
+	}
+
+	/* We can only originate opaque LSAs */
+	if (!IS_OPAQUE_LSA(lsa_type)) {
+		fprintf(stderr, "Cannot originate non-opaque LSA type %d\n",
+			lsa_type);
+		return OSPF_API_ILLEGALLSATYPE;
+	}
+
+	if ((size_t)opaquelen > sizeof(buf) - sizeof(struct lsa_header)) {
+		fprintf(stderr, "opaquelen(%d) is larger than buf size %zu\n",
+			opaquelen, sizeof(buf));
+		return OSPF_API_NOMEMORY;
+	}
+
+	/* Make a new LSA from parameters */
+	lsah = (struct lsa_header *)buf;
+	lsah->ls_age = 0;
+	lsah->options = 0;
+	lsah->type = lsa_type;
+
+	tmp = SET_OPAQUE_LSID(opaque_type, opaque_id);
+	lsah->id.s_addr = htonl(tmp);
+	lsah->adv_router.s_addr = INADDR_ANY;
+	lsah->ls_seqnum = 0;
+	lsah->checksum = 0;
+	lsah->length = htons(sizeof(struct lsa_header) + opaquelen);
+
+	memcpy(((uint8_t *)lsah) + sizeof(struct lsa_header), opaquedata,
+	       opaquelen);
+
+	msg = new_msg_originate_request(ospf_apiclient_get_seqnr(), ifaddr,
+					area_id, lsah);
+	if (!msg) {
+		fprintf(stderr, "new_msg_originate_request failed\n");
+		return OSPF_API_NOMEMORY;
+	}
+
+	rc = ospf_apiclient_send_request(oclient, msg);
+	return rc;
+}
+
+int ospf_apiclient_lsa_delete(struct ospf_apiclient *oclient,
+			      struct in_addr addr, uint8_t lsa_type,
+			      uint8_t opaque_type, uint32_t opaque_id,
+			      uint8_t flags)
+{
+	struct msg *msg;
+	int rc;
+
+	/* Only opaque LSA can be deleted */
+	if (!IS_OPAQUE_LSA(lsa_type)) {
+		fprintf(stderr, "Cannot delete non-opaque LSA type %d\n",
+			lsa_type);
+		return OSPF_API_ILLEGALLSATYPE;
+	}
+
+	/* opaque_id is in host byte order and will be converted
+	 * to network byte order by new_msg_delete_request */
+	msg = new_msg_delete_request(ospf_apiclient_get_seqnr(), addr, lsa_type,
+				     opaque_type, opaque_id, flags);
+
+	rc = ospf_apiclient_send_request(oclient, msg);
+	return rc;
+}
+
+/* -----------------------------------------------------------
+ * Following are handlers for messages from OSPF daemon
+ * -----------------------------------------------------------
+ */
+
+static void ospf_apiclient_handle_ready(struct ospf_apiclient *oclient,
+					struct msg *msg)
+{
+	struct msg_ready_notify *r;
+	r = (struct msg_ready_notify *)STREAM_DATA(msg->s);
+
+	/* Invoke registered callback function. */
+	if (oclient->ready_notify) {
+		(oclient->ready_notify)(r->lsa_type, r->opaque_type, r->addr);
+	}
+}
+
+static void ospf_apiclient_handle_new_if(struct ospf_apiclient *oclient,
+					 struct msg *msg)
+{
+	struct msg_new_if *n;
+	n = (struct msg_new_if *)STREAM_DATA(msg->s);
+
+	/* Invoke registered callback function. */
+	if (oclient->new_if) {
+		(oclient->new_if)(n->ifaddr, n->area_id);
+	}
+}
+
+static void ospf_apiclient_handle_del_if(struct ospf_apiclient *oclient,
+					 struct msg *msg)
+{
+	struct msg_del_if *d;
+	d = (struct msg_del_if *)STREAM_DATA(msg->s);
+
+	/* Invoke registered callback function. */
+	if (oclient->del_if) {
+		(oclient->del_if)(d->ifaddr);
+	}
+}
+
+static void ospf_apiclient_handle_ism_change(struct ospf_apiclient *oclient,
+					     struct msg *msg)
+{
+	struct msg_ism_change *m;
+	m = (struct msg_ism_change *)STREAM_DATA(msg->s);
+
+	/* Invoke registered callback function. */
+	if (oclient->ism_change) {
+		(oclient->ism_change)(m->ifaddr, m->area_id, m->status);
+	}
+}
+
+static void ospf_apiclient_handle_nsm_change(struct ospf_apiclient *oclient,
+					     struct msg *msg)
+{
+	struct msg_nsm_change *m;
+	m = (struct msg_nsm_change *)STREAM_DATA(msg->s);
+
+	/* Invoke registered callback function. */
+	if (oclient->nsm_change) {
+		(oclient->nsm_change)(m->ifaddr, m->nbraddr, m->router_id,
+				      m->status);
+	}
+}
+
+static void ospf_apiclient_handle_lsa_update(struct ospf_apiclient *oclient,
+					     struct msg *msg)
+{
+	struct msg_lsa_change_notify *cn;
+	struct lsa_header *lsa;
+	void *p;
+	uint16_t lsalen;
+
+	cn = (struct msg_lsa_change_notify *)STREAM_DATA(msg->s);
+
+	/* Extract LSA from message */
+	lsalen = ntohs(cn->data.length);
+	if (lsalen > OSPF_MAX_LSA_SIZE) {
+		flog_warn(
+			EC_OSPF_LARGE_LSA,
+			"%s: message received size: %d is greater than a LSA size: %d",
+			__func__, lsalen, OSPF_MAX_LSA_SIZE);
+		return;
+	}
+
+	p = XMALLOC(MTYPE_OSPF_APICLIENT, lsalen);
+
+	memcpy(p, &(cn->data), lsalen);
+	lsa = p;
+
+	/* Invoke registered update callback function */
+	if (oclient->update_notify) {
+		(oclient->update_notify)(cn->ifaddr, cn->area_id,
+					 cn->is_self_originated, lsa);
+	}
+
+	/* free memory allocated by ospf apiclient library */
+	XFREE(MTYPE_OSPF_APICLIENT, p);
+}
+
+static void ospf_apiclient_handle_lsa_delete(struct ospf_apiclient *oclient,
+					     struct msg *msg)
+{
+	struct msg_lsa_change_notify *cn;
+	struct lsa_header *lsa;
+	void *p;
+	uint16_t lsalen;
+
+	cn = (struct msg_lsa_change_notify *)STREAM_DATA(msg->s);
+
+	/* Extract LSA from message */
+	lsalen = ntohs(cn->data.length);
+	if (lsalen > OSPF_MAX_LSA_SIZE) {
+		flog_warn(
+			EC_OSPF_LARGE_LSA,
+			"%s: message received size: %d is greater than a LSA size: %d",
+			__func__, lsalen, OSPF_MAX_LSA_SIZE);
+		return;
+	}
+
+	p = XMALLOC(MTYPE_OSPF_APICLIENT, lsalen);
+
+	memcpy(p, &(cn->data), lsalen);
+	lsa = p;
+
+	/* Invoke registered update callback function */
+	if (oclient->delete_notify) {
+		(oclient->delete_notify)(cn->ifaddr, cn->area_id,
+					 cn->is_self_originated, lsa);
+	}
+
+	/* free memory allocated by ospf apiclient library */
+	XFREE(MTYPE_OSPF_APICLIENT, p);
+}
+
+static void ospf_apiclient_msghandle(struct ospf_apiclient *oclient,
+				     struct msg *msg)
+{
+	/* Call message handler function. */
+	switch (msg->hdr.msgtype) {
+	case MSG_READY_NOTIFY:
+		ospf_apiclient_handle_ready(oclient, msg);
+		break;
+	case MSG_NEW_IF:
+		ospf_apiclient_handle_new_if(oclient, msg);
+		break;
+	case MSG_DEL_IF:
+		ospf_apiclient_handle_del_if(oclient, msg);
+		break;
+	case MSG_ISM_CHANGE:
+		ospf_apiclient_handle_ism_change(oclient, msg);
+		break;
+	case MSG_NSM_CHANGE:
+		ospf_apiclient_handle_nsm_change(oclient, msg);
+		break;
+	case MSG_LSA_UPDATE_NOTIFY:
+		ospf_apiclient_handle_lsa_update(oclient, msg);
+		break;
+	case MSG_LSA_DELETE_NOTIFY:
+		ospf_apiclient_handle_lsa_delete(oclient, msg);
+		break;
+	default:
+		fprintf(stderr,
+			"ospf_apiclient_read: Unknown message type: %d\n",
+			msg->hdr.msgtype);
+		break;
+	}
+}
+
+/* -----------------------------------------------------------
+ * Callback handler registration
+ * -----------------------------------------------------------
+ */
+
+void ospf_apiclient_register_callback(
+	struct ospf_apiclient *oclient,
+	void (*ready_notify)(uint8_t lsa_type, uint8_t opaque_type,
+			     struct in_addr addr),
+	void (*new_if)(struct in_addr ifaddr, struct in_addr area_id),
+	void (*del_if)(struct in_addr ifaddr),
+	void (*ism_change)(struct in_addr ifaddr, struct in_addr area_id,
+			   uint8_t status),
+	void (*nsm_change)(struct in_addr ifaddr, struct in_addr nbraddr,
+			   struct in_addr router_id, uint8_t status),
+	void (*update_notify)(struct in_addr ifaddr, struct in_addr area_id,
+			      uint8_t self_origin, struct lsa_header *lsa),
+	void (*delete_notify)(struct in_addr ifaddr, struct in_addr area_id,
+			      uint8_t self_origin, struct lsa_header *lsa))
+{
+	assert(oclient);
+	assert(update_notify);
+
+	/* Register callback function */
+	oclient->ready_notify = ready_notify;
+	oclient->new_if = new_if;
+	oclient->del_if = del_if;
+	oclient->ism_change = ism_change;
+	oclient->nsm_change = nsm_change;
+	oclient->update_notify = update_notify;
+	oclient->delete_notify = delete_notify;
+}
+
+/* -----------------------------------------------------------
+ * Asynchronous message handling
+ * -----------------------------------------------------------
+ */
+
+int ospf_apiclient_handle_async(struct ospf_apiclient *oclient)
+{
+	struct msg *msg;
+
+	/* Get a message */
+	msg = msg_read(oclient->fd_async);
+
+	if (!msg) {
+		/* Connection broke down */
+		return -1;
+	}
+
+	/* Handle message */
+	ospf_apiclient_msghandle(oclient, msg);
+
+	/* Don't forget to free this message */
+	msg_free(msg);
+
+	return 0;
+}
diff --git a/ospfclient/ospf_apiclient.h b/ospfclient/ospf_apiclient.h
new file mode 100644
index 0000000..b904937
--- /dev/null
+++ b/ospfclient/ospf_apiclient.h
@@ -0,0 +1,104 @@
+/*
+ * Client side of OSPF API.
+ * Copyright (C) 2001, 2002, 2003 Ralph Keller
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra 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 2, or (at your
+ * option) any later version.
+ *
+ * GNU Zebra 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; see the file COPYING; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef _OSPF_APICLIENT_H
+#define _OSPF_APICLIENT_H
+
+/* Structure for the OSPF API client */
+struct ospf_apiclient {
+
+	/* Sockets for sync requests and async notifications */
+	int fd_sync;
+	int fd_async;
+
+	/* Pointer to callback functions */
+	void (*ready_notify)(uint8_t lsa_type, uint8_t opaque_type,
+			     struct in_addr addr);
+	void (*new_if)(struct in_addr ifaddr, struct in_addr area_id);
+	void (*del_if)(struct in_addr ifaddr);
+	void (*ism_change)(struct in_addr ifaddr, struct in_addr area_id,
+			   uint8_t status);
+	void (*nsm_change)(struct in_addr ifaddr, struct in_addr nbraddr,
+			   struct in_addr router_id, uint8_t status);
+	void (*update_notify)(struct in_addr ifaddr, struct in_addr area_id,
+			      uint8_t self_origin, struct lsa_header *lsa);
+	void (*delete_notify)(struct in_addr ifaddr, struct in_addr area_id,
+			      uint8_t self_origin, struct lsa_header *lsa);
+};
+
+
+/* ---------------------------------------------------------
+ * API function prototypes.
+ * --------------------------------------------------------- */
+
+/* Open connection to OSPF daemon. Two ports will be allocated on
+   client, sync channel at syncport and reverse channel at syncport+1 */
+struct ospf_apiclient *ospf_apiclient_connect(char *host, int syncport);
+
+/* Shutdown connection to OSPF daemon. */
+int ospf_apiclient_close(struct ospf_apiclient *oclient);
+
+/* Synchronous request to register opaque type. */
+int ospf_apiclient_register_opaque_type(struct ospf_apiclient *oclient,
+					uint8_t ltype, uint8_t otype);
+
+/* Synchronous request to register event mask. */
+int ospf_apiclient_register_events(struct ospf_apiclient *oclient,
+				   uint32_t mask);
+
+/* Register callback functions.*/
+void ospf_apiclient_register_callback(
+	struct ospf_apiclient *oclient,
+	void (*ready_notify)(uint8_t lsa_type, uint8_t opaque_type,
+			     struct in_addr addr),
+	void (*new_if)(struct in_addr ifaddr, struct in_addr area_id),
+	void (*del_if)(struct in_addr ifaddr),
+	void (*ism_change)(struct in_addr ifaddr, struct in_addr area_id,
+			   uint8_t status),
+	void (*nsm_change)(struct in_addr ifaddr, struct in_addr nbraddr,
+			   struct in_addr router_id, uint8_t status),
+	void (*update_notify)(struct in_addr ifaddr, struct in_addr area_id,
+			      uint8_t selforig, struct lsa_header *lsa),
+	void (*delete_notify)(struct in_addr ifaddr, struct in_addr area_id,
+			      uint8_t selforig, struct lsa_header *lsa));
+
+/* Synchronous request to synchronize LSDB. */
+int ospf_apiclient_sync_lsdb(struct ospf_apiclient *oclient);
+
+/* Synchronous request to originate or update opaque LSA. */
+int ospf_apiclient_lsa_originate(struct ospf_apiclient *oclient,
+				 struct in_addr ifaddr, struct in_addr area_id,
+				 uint8_t lsa_type, uint8_t opaque_type,
+				 uint32_t opaque_id, void *opaquedata,
+				 int opaquelen);
+
+
+/* Synchronous request to delete opaque LSA. Parameter opaque_id is in
+   host byte order */
+int ospf_apiclient_lsa_delete(struct ospf_apiclient *oclient,
+			      struct in_addr addr, uint8_t lsa_type,
+			      uint8_t opaque_type, uint32_t opaque_id,
+			      uint8_t flags);
+
+/* Fetch async message and handle it  */
+int ospf_apiclient_handle_async(struct ospf_apiclient *oclient);
+
+#endif /* _OSPF_APICLIENT_H */
diff --git a/ospfclient/ospfclient.c b/ospfclient/ospfclient.c
new file mode 100644
index 0000000..edf8141
--- /dev/null
+++ b/ospfclient/ospfclient.c
@@ -0,0 +1,342 @@
+/* This file is part of Quagga.
+ *
+ * Quagga 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 2, or (at your option) any
+ * later version.
+ *
+ * Quagga 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; see the file COPYING; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/*
+ * Simple program to demonstrate how OSPF API can be used. This
+ * application retrieves the LSDB from the OSPF daemon and then
+ * originates, updates and finally deletes an application-specific
+ * opaque LSA. You can use this application as a template when writing
+ * your own application.
+ */
+
+/* The following includes are needed in all OSPF API client
+   applications. */
+
+#include <zebra.h>
+#include "prefix.h" /* needed by ospf_asbr.h */
+#include "privs.h"
+#include "log.h"
+#include "lib/printfrr.h"
+
+/* work around gcc bug 69981, disable MTYPEs in libospf */
+#define _QUAGGA_OSPF_MEMORY_H
+
+#include "ospfd/ospfd.h"
+#include "ospfd/ospf_asbr.h"
+#include "ospfd/ospf_lsa.h"
+#include "ospfd/ospf_opaque.h"
+#include "ospfd/ospf_api.h"
+#include "ospf_apiclient.h"
+
+/* privileges struct.
+ * set cap_num_* and uid/gid to nothing to use NULL privs
+ * as ospfapiclient links in libospf.a which uses privs.
+ */
+struct zebra_privs_t ospfd_privs = {.user = NULL,
+				    .group = NULL,
+				    .cap_num_p = 0,
+				    .cap_num_i = 0};
+
+/* The following includes are specific to this application. For
+   example it uses threads from libfrr, however your application is
+   free to use any thread library (like pthreads). */
+
+#include "ospfd/ospf_dump.h" /* for ospf_lsa_header_dump */
+#include "thread.h"
+#include "log.h"
+
+/* Local portnumber for async channel. Note that OSPF API library will also
+   allocate a sync channel at ASYNCPORT+1. */
+#define ASYNCPORT 4000
+
+/* Master thread */
+struct thread_master *master;
+
+/* Global variables */
+struct ospf_apiclient *oclient;
+char **args;
+
+/* Our opaque LSAs have the following format. */
+struct my_opaque_lsa {
+	struct lsa_header hdr; /* include common LSA header */
+	uint8_t data[4];       /* our own data format then follows here */
+};
+
+
+/* ---------------------------------------------------------
+ * Threads for asynchronous messages and LSA update/delete
+ * ---------------------------------------------------------
+ */
+
+static void lsa_delete(struct thread *t)
+{
+	struct ospf_apiclient *oclient;
+	struct in_addr area_id;
+	int rc;
+
+	oclient = THREAD_ARG(t);
+
+	rc = inet_aton(args[6], &area_id);
+	if (rc <= 0) {
+		printf("Address Specified: %s is invalid\n", args[6]);
+		return;
+	}
+
+	printf("Deleting LSA... ");
+	rc = ospf_apiclient_lsa_delete(oclient, area_id,
+				       atoi(args[2]), /* lsa type */
+				       atoi(args[3]), /* opaque type */
+				       atoi(args[4]), /* opaque ID */
+				       0); /* send data in withdrawals */
+	printf("done, return code is = %d\n", rc);
+}
+
+static void lsa_inject(struct thread *t)
+{
+	struct ospf_apiclient *cl;
+	struct in_addr ifaddr;
+	struct in_addr area_id;
+	uint8_t lsa_type;
+	uint8_t opaque_type;
+	uint32_t opaque_id;
+	void *opaquedata;
+	int opaquelen;
+
+	static uint32_t counter = 1; /* Incremented each time invoked */
+	int rc;
+
+	cl = THREAD_ARG(t);
+
+	rc = inet_aton(args[5], &ifaddr);
+	if (rc <= 0) {
+		printf("Ifaddr specified %s is invalid\n", args[5]);
+		return;
+	}
+
+	rc = inet_aton(args[6], &area_id);
+	if (rc <= 0) {
+		printf("Area ID specified %s is invalid\n", args[6]);
+		return;
+	}
+	lsa_type = atoi(args[2]);
+	opaque_type = atoi(args[3]);
+	opaque_id = atoi(args[4]);
+	opaquedata = &counter;
+	opaquelen = sizeof(uint32_t);
+
+	printf("Originating/updating LSA with counter=%d... ", counter);
+	rc = ospf_apiclient_lsa_originate(cl, ifaddr, area_id, lsa_type,
+					  opaque_type, opaque_id, opaquedata,
+					  opaquelen);
+
+	printf("done, return code is %d\n", rc);
+
+	counter++;
+}
+
+
+/* This thread handles asynchronous messages coming in from the OSPF
+   API server */
+static void lsa_read(struct thread *thread)
+{
+	struct ospf_apiclient *oclient;
+	int fd;
+	int ret;
+
+	printf("lsa_read called\n");
+
+	oclient = THREAD_ARG(thread);
+	fd = THREAD_FD(thread);
+
+	/* Handle asynchronous message */
+	ret = ospf_apiclient_handle_async(oclient);
+	if (ret < 0) {
+		printf("Connection closed, exiting...");
+		exit(0);
+	}
+
+	/* Reschedule read thread */
+	thread_add_read(master, lsa_read, oclient, fd, NULL);
+}
+
+/* ---------------------------------------------------------
+ * Callback functions for asynchronous events
+ * ---------------------------------------------------------
+ */
+
+static void lsa_update_callback(struct in_addr ifaddr, struct in_addr area_id,
+				uint8_t is_self_originated,
+				struct lsa_header *lsa)
+{
+	printf("lsa_update_callback: ");
+	printfrr("ifaddr: %pI4 ", &ifaddr);
+	printfrr("area: %pI4\n", &area_id);
+	printf("is_self_origin: %u\n", is_self_originated);
+
+	/* It is important to note that lsa_header does indeed include the
+	   header and the LSA payload. To access the payload, first check
+	   the LSA type and then typecast lsa into the corresponding type,
+	   e.g.:
+
+	   if (lsa->type == OSPF_ROUTER_LSA) {
+	     struct router_lsa *rl = (struct router_lsa) lsa;
+	     ...
+	     uint16_t links = rl->links;
+	     ...
+	  }
+	*/
+
+	ospf_lsa_header_dump(lsa);
+}
+
+static void lsa_delete_callback(struct in_addr ifaddr, struct in_addr area_id,
+				uint8_t is_self_originated,
+				struct lsa_header *lsa)
+{
+	printf("lsa_delete_callback: ");
+	printf("ifaddr: %pI4 ", &ifaddr);
+	printf("area: %pI4\n", &area_id);
+	printf("is_self_origin: %u\n", is_self_originated);
+
+	ospf_lsa_header_dump(lsa);
+}
+
+static void ready_callback(uint8_t lsa_type, uint8_t opaque_type,
+			   struct in_addr addr)
+{
+	printfrr("ready_callback: lsa_type: %d opaque_type: %d addr=%pI4\n",
+		 lsa_type, opaque_type, &addr);
+
+	/* Schedule opaque LSA originate in 5 secs */
+	thread_add_timer(master, lsa_inject, oclient, 5, NULL);
+
+	/* Schedule opaque LSA update with new value */
+	thread_add_timer(master, lsa_inject, oclient, 10, NULL);
+
+	/* Schedule delete */
+	thread_add_timer(master, lsa_delete, oclient, 30, NULL);
+}
+
+static void new_if_callback(struct in_addr ifaddr, struct in_addr area_id)
+{
+	printfrr("new_if_callback: ifaddr: %pI4 ", &ifaddr);
+	printfrr("area_id: %pI4\n", &area_id);
+}
+
+static void del_if_callback(struct in_addr ifaddr)
+{
+	printfrr("new_if_callback: ifaddr: %pI4\n ", &ifaddr);
+}
+
+static void ism_change_callback(struct in_addr ifaddr, struct in_addr area_id,
+				uint8_t state)
+{
+	printfrr("ism_change: ifaddr: %pI4 ", &ifaddr);
+	printfrr("area_id: %pI4\n", &area_id);
+	printf("state: %d [%s]\n", state,
+	       lookup_msg(ospf_ism_state_msg, state, NULL));
+}
+
+static void nsm_change_callback(struct in_addr ifaddr, struct in_addr nbraddr,
+				struct in_addr router_id, uint8_t state)
+{
+	printfrr("nsm_change: ifaddr: %pI4 ", &ifaddr);
+	printfrr("nbraddr: %pI4\n", &nbraddr);
+	printfrr("router_id: %pI4\n", &router_id);
+	printf("state: %d [%s]\n", state,
+	       lookup_msg(ospf_nsm_state_msg, state, NULL));
+}
+
+
+/* ---------------------------------------------------------
+ * Main program
+ * ---------------------------------------------------------
+ */
+
+static int usage(void)
+{
+	printf("Usage: ospfclient <ospfd> <lsatype> <opaquetype> <opaqueid> <ifaddr> <areaid>\n");
+	printf("where ospfd     : router where API-enabled OSPF daemon is running\n");
+	printf("      lsatype   : either 9, 10, or 11 depending on flooding scope\n");
+	printf("      opaquetype: 0-255 (e.g., experimental applications use > 128)\n");
+	printf("      opaqueid  : arbitrary application instance (24 bits)\n");
+	printf("      ifaddr    : interface IP address (for type 9) otherwise ignored\n");
+	printf("      areaid    : area in IP address format (for type 10) otherwise ignored\n");
+
+	exit(1);
+}
+
+int main(int argc, char *argv[])
+{
+	struct thread thread;
+
+	args = argv;
+
+	/* ospfclient should be started with the following arguments:
+	 *
+	 * (1) host (2) lsa_type (3) opaque_type (4) opaque_id (5) if_addr
+	 * (6) area_id
+	 *
+	 * host: name or IP of host where ospfd is running
+	 * lsa_type: 9, 10, or 11
+	 * opaque_type: 0-255 (e.g., experimental applications use > 128)
+	 * opaque_id: arbitrary application instance (24 bits)
+	 * if_addr: interface IP address (for type 9) otherwise ignored
+	 * area_id: area in IP address format (for type 10) otherwise ignored
+	 */
+
+	if (argc != 7) {
+		usage();
+	}
+
+	/* Initialization */
+	zprivs_preinit(&ospfd_privs);
+	zprivs_init(&ospfd_privs);
+	master = thread_master_create(NULL);
+
+	/* Open connection to OSPF daemon */
+	oclient = ospf_apiclient_connect(args[1], ASYNCPORT);
+	if (!oclient) {
+		printf("Connecting to OSPF daemon on %s failed!\n", args[1]);
+		exit(1);
+	}
+
+	/* Register callback functions. */
+	ospf_apiclient_register_callback(
+		oclient, ready_callback, new_if_callback, del_if_callback,
+		ism_change_callback, nsm_change_callback, lsa_update_callback,
+		lsa_delete_callback);
+
+	/* Register LSA type and opaque type. */
+	ospf_apiclient_register_opaque_type(oclient, atoi(args[2]),
+					    atoi(args[3]));
+
+	/* Synchronize database with OSPF daemon. */
+	ospf_apiclient_sync_lsdb(oclient);
+
+	/* Schedule thread that handles asynchronous messages */
+	thread_add_read(master, lsa_read, oclient, oclient->fd_async, NULL);
+
+	/* Now connection is established, run loop */
+	while (1) {
+		thread_fetch(master, &thread);
+		thread_call(&thread);
+	}
+
+	/* Never reached */
+	return 0;
+}
diff --git a/ospfclient/ospfclient.py b/ospfclient/ospfclient.py
new file mode 100755
index 0000000..f93d633
--- /dev/null
+++ b/ospfclient/ospfclient.py
@@ -0,0 +1,1240 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 eval: (blacken-mode 1) -*-
+#
+# December 22 2021, Christian Hopps <chopps@labn.net>
+#
+# Copyright 2021-2022, LabN Consulting, L.L.C.
+#
+# 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 2
+# 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; see the file COPYING; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+#
+
+import argparse
+import asyncio
+import errno
+import logging
+import socket
+import struct
+import sys
+from asyncio import Event, Lock
+from ipaddress import ip_address as ip
+
+FMT_APIMSGHDR = ">BBHL"
+FMT_APIMSGHDR_SIZE = struct.calcsize(FMT_APIMSGHDR)
+
+FMT_LSA_FILTER = ">HBB"  # + plus x"I" areas
+LSAF_ORIGIN_NON_SELF = 0
+LSAF_ORIGIN_SELF = 1
+LSAF_ORIGIN_ANY = 2
+
+FMT_LSA_HEADER = ">HBBIILHH"
+FMT_LSA_HEADER_SIZE = struct.calcsize(FMT_LSA_HEADER)
+
+# ------------------------
+# Messages to OSPF daemon.
+# ------------------------
+
+MSG_REGISTER_OPAQUETYPE = 1
+MSG_UNREGISTER_OPAQUETYPE = 2
+MSG_REGISTER_EVENT = 3
+MSG_SYNC_LSDB = 4
+MSG_ORIGINATE_REQUEST = 5
+MSG_DELETE_REQUEST = 6
+MSG_SYNC_REACHABLE = 7
+MSG_SYNC_ISM = 8
+MSG_SYNC_NSM = 9
+MSG_SYNC_ROUTER_ID = 19
+
+smsg_info = {
+    MSG_REGISTER_OPAQUETYPE: ("REGISTER_OPAQUETYPE", "BBxx"),
+    MSG_UNREGISTER_OPAQUETYPE: ("UNREGISTER_OPAQUETYPE", "BBxx"),
+    MSG_REGISTER_EVENT: ("REGISTER_EVENT", FMT_LSA_FILTER),
+    MSG_SYNC_LSDB: ("SYNC_LSDB", FMT_LSA_FILTER),
+    MSG_ORIGINATE_REQUEST: ("ORIGINATE_REQUEST", ">II" + FMT_LSA_HEADER[1:]),
+    MSG_DELETE_REQUEST: ("DELETE_REQUEST", ">IBBxBL"),
+    MSG_SYNC_REACHABLE: ("MSG_SYNC_REACHABLE", ""),
+    MSG_SYNC_ISM: ("MSG_SYNC_ISM", ""),
+    MSG_SYNC_NSM: ("MSG_SYNC_NSM", ""),
+    MSG_SYNC_ROUTER_ID: ("MSG_SYNC_ROUTER_ID", ""),
+}
+
+# OSPF API MSG Delete Flag.
+OSPF_API_DEL_ZERO_LEN_LSA = 0x01  # send withdrawal with no LSA data
+
+# --------------------------
+# Messages from OSPF daemon.
+# --------------------------
+
+MSG_REPLY = 10
+MSG_READY_NOTIFY = 11
+MSG_LSA_UPDATE_NOTIFY = 12
+MSG_LSA_DELETE_NOTIFY = 13
+MSG_NEW_IF = 14
+MSG_DEL_IF = 15
+MSG_ISM_CHANGE = 16
+MSG_NSM_CHANGE = 17
+MSG_REACHABLE_CHANGE = 18
+MSG_ROUTER_ID_CHANGE = 20
+
+amsg_info = {
+    MSG_REPLY: ("REPLY", "bxxx"),
+    MSG_READY_NOTIFY: ("READY_NOTIFY", ">BBxxI"),
+    MSG_LSA_UPDATE_NOTIFY: ("LSA_UPDATE_NOTIFY", ">IIBxxx" + FMT_LSA_HEADER[1:]),
+    MSG_LSA_DELETE_NOTIFY: ("LSA_DELETE_NOTIFY", ">IIBxxx" + FMT_LSA_HEADER[1:]),
+    MSG_NEW_IF: ("NEW_IF", ">II"),
+    MSG_DEL_IF: ("DEL_IF", ">I"),
+    MSG_ISM_CHANGE: ("ISM_CHANGE", ">IIBxxx"),
+    MSG_NSM_CHANGE: ("NSM_CHANGE", ">IIIBxxx"),
+    MSG_REACHABLE_CHANGE: ("REACHABLE_CHANGE", ">HH"),
+    MSG_ROUTER_ID_CHANGE: ("ROUTER_ID_CHANGE", ">I"),
+}
+
+OSPF_API_OK = 0
+OSPF_API_NOSUCHINTERFACE = -1
+OSPF_API_NOSUCHAREA = -2
+OSPF_API_NOSUCHLSA = -3
+OSPF_API_ILLEGALLSATYPE = -4
+OSPF_API_OPAQUETYPEINUSE = -5
+OSPF_API_OPAQUETYPENOTREGISTERED = -6
+OSPF_API_NOTREADY = -7
+OSPF_API_NOMEMORY = -8
+OSPF_API_ERROR = -9
+OSPF_API_UNDEF = -10
+
+msg_errname = {
+    OSPF_API_OK: "OSPF_API_OK",
+    OSPF_API_NOSUCHINTERFACE: "OSPF_API_NOSUCHINTERFACE",
+    OSPF_API_NOSUCHAREA: "OSPF_API_NOSUCHAREA",
+    OSPF_API_NOSUCHLSA: "OSPF_API_NOSUCHLSA",
+    OSPF_API_ILLEGALLSATYPE: "OSPF_API_ILLEGALLSATYPE",
+    OSPF_API_OPAQUETYPEINUSE: "OSPF_API_OPAQUETYPEINUSE",
+    OSPF_API_OPAQUETYPENOTREGISTERED: "OSPF_API_OPAQUETYPENOTREGISTERED",
+    OSPF_API_NOTREADY: "OSPF_API_NOTREADY",
+    OSPF_API_NOMEMORY: "OSPF_API_NOMEMORY",
+    OSPF_API_ERROR: "OSPF_API_ERROR",
+    OSPF_API_UNDEF: "OSPF_API_UNDEF",
+}
+
+# msg_info = {**smsg_info, **amsg_info}
+msg_info = {}
+msg_info.update(smsg_info)
+msg_info.update(amsg_info)
+msg_name = {k: v[0] for k, v in msg_info.items()}
+msg_fmt = {k: v[1] for k, v in msg_info.items()}
+msg_size = {k: struct.calcsize(v) for k, v in msg_fmt.items()}
+
+
+def api_msgname(mt):
+    return msg_name.get(mt, str(mt))
+
+
+def api_errname(ecode):
+    return msg_errname.get(ecode, str(ecode))
+
+
+# -------------------
+# API Semantic Errors
+# -------------------
+
+
+class APIError(Exception):
+    pass
+
+
+class MsgTypeError(Exception):
+    pass
+
+
+class SeqNumError(Exception):
+    pass
+
+
+# ---------
+# LSA Types
+# ---------
+
+LSA_TYPE_UNKNOWN = 0
+LSA_TYPE_ROUTER = 1
+LSA_TYPE_NETWORK = 2
+LSA_TYPE_SUMMARY = 3
+LSA_TYPE_ASBR_SUMMARY = 4
+LSA_TYPE_AS_EXTERNAL = 5
+LSA_TYPE_GROUP_MEMBER = 6
+LSA_TYPE_AS_NSSA = 7
+LSA_TYPE_EXTERNAL_ATTRIBUTES = 8
+LSA_TYPE_OPAQUE_LINK = 9
+LSA_TYPE_OPAQUE_AREA = 10
+LSA_TYPE_OPAQUE_AS = 11
+
+
+def lsa_typename(lsa_type):
+    names = {
+        LSA_TYPE_ROUTER: "LSA:ROUTER",
+        LSA_TYPE_NETWORK: "LSA:NETWORK",
+        LSA_TYPE_SUMMARY: "LSA:SUMMARY",
+        LSA_TYPE_ASBR_SUMMARY: "LSA:ASBR_SUMMARY",
+        LSA_TYPE_AS_EXTERNAL: "LSA:AS_EXTERNAL",
+        LSA_TYPE_GROUP_MEMBER: "LSA:GROUP_MEMBER",
+        LSA_TYPE_AS_NSSA: "LSA:AS_NSSA",
+        LSA_TYPE_EXTERNAL_ATTRIBUTES: "LSA:EXTERNAL_ATTRIBUTES",
+        LSA_TYPE_OPAQUE_LINK: "LSA:OPAQUE_LINK",
+        LSA_TYPE_OPAQUE_AREA: "LSA:OPAQUE_AREA",
+        LSA_TYPE_OPAQUE_AS: "LSA:OPAQUE_AS",
+    }
+    return names.get(lsa_type, str(lsa_type))
+
+
+# ------------------------------
+# Interface State Machine States
+# ------------------------------
+
+ISM_DEPENDUPON = 0
+ISM_DOWN = 1
+ISM_LOOPBACK = 2
+ISM_WAITING = 3
+ISM_POINTTOPOINT = 4
+ISM_DROTHER = 5
+ISM_BACKUP = 6
+ISM_DR = 7
+
+
+def ism_name(state):
+    names = {
+        ISM_DEPENDUPON: "ISM_DEPENDUPON",
+        ISM_DOWN: "ISM_DOWN",
+        ISM_LOOPBACK: "ISM_LOOPBACK",
+        ISM_WAITING: "ISM_WAITING",
+        ISM_POINTTOPOINT: "ISM_POINTTOPOINT",
+        ISM_DROTHER: "ISM_DROTHER",
+        ISM_BACKUP: "ISM_BACKUP",
+        ISM_DR: "ISM_DR",
+    }
+    return names.get(state, str(state))
+
+
+# -----------------------------
+# Neighbor State Machine States
+# -----------------------------
+
+NSM_DEPENDUPON = 0
+NSM_DELETED = 1
+NSM_DOWN = 2
+NSM_ATTEMPT = 3
+NSM_INIT = 4
+NSM_TWOWAY = 5
+NSM_EXSTART = 6
+NSM_EXCHANGE = 7
+NSM_LOADING = 8
+NSM_FULL = 9
+
+
+def nsm_name(state):
+    names = {
+        NSM_DEPENDUPON: "NSM_DEPENDUPON",
+        NSM_DELETED: "NSM_DELETED",
+        NSM_DOWN: "NSM_DOWN",
+        NSM_ATTEMPT: "NSM_ATTEMPT",
+        NSM_INIT: "NSM_INIT",
+        NSM_TWOWAY: "NSM_TWOWAY",
+        NSM_EXSTART: "NSM_EXSTART",
+        NSM_EXCHANGE: "NSM_EXCHANGE",
+        NSM_LOADING: "NSM_LOADING",
+        NSM_FULL: "NSM_FULL",
+    }
+    return names.get(state, str(state))
+
+
+class WithNothing:
+    "An object that does nothing when used with `with` statement."
+
+    async def __aenter__(self):
+        return
+
+    async def __aexit__(self, *args, **kwargs):
+        return
+
+
+# --------------
+# Client Classes
+# --------------
+
+
+class OspfApiClient:
+    def __str__(self):
+        return "OspfApiClient({})".format(self.server)
+
+    @staticmethod
+    def _get_bound_sockets(port):
+        s1 = socket.socket(socket.AF_INET, socket.SOCK_STREAM, 0)
+        try:
+            s1.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+            # s1.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)
+            s1.bind(("", port))
+            s2 = socket.socket(socket.AF_INET, socket.SOCK_STREAM, 0)
+            try:
+                s2.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+                # s2.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)
+                s2.bind(("", port + 1))
+                return s1, s2
+            except Exception:
+                s2.close()
+                raise
+        except Exception:
+            s1.close()
+            raise
+
+    def __init__(self, server="localhost", handlers=None):
+        """A client connection to OSPF Daemon using the OSPF API
+
+        The client object is not created in a connected state.  To connect to the server
+        the `connect` method should be called.  If an error is encountered when sending
+        messages to the server an exception will be raised and the connection will be
+        closed.  When this happens `connect` may be called again to restore the
+        connection.
+
+        Args:
+            server: hostname or IP address of server default is "localhost"
+            handlers: dict of message handlers, the key is the API message
+                type, the value is a function. The functions signature is:
+                `handler(msg_type, msg, msg_extra, *params)`, where `msg` is the
+                message data after the API header, `*params` will be the
+                unpacked message values, and msg_extra are any bytes beyond the
+                fixed parameters of the message.
+        Raises:
+            Will raise exceptions for failures with various `socket` modules
+            functions such as `socket.socket`, `socket.setsockopt`, `socket.bind`.
+        """
+        self._seq = 0
+        self._s = None
+        self._as = None
+        self._ls = None
+        self._ar = self._r = self._w = None
+        self.server = server
+        self.handlers = handlers if handlers is not None else dict()
+        self.write_lock = Lock()
+
+        # try and get consecutive 2 ports
+        PORTSTART = 49152
+        PORTEND = 65534
+        for port in range(PORTSTART, PORTEND + 2, 2):
+            try:
+                logging.debug("%s: binding to ports %s, %s", self, port, port + 1)
+                self._s, self._ls = self._get_bound_sockets(port)
+                break
+            except OSError as error:
+                if error.errno != errno.EADDRINUSE or port == PORTEND:
+                    logging.warning("%s: binding port %s error %s", self, port, error)
+                    raise
+                logging.debug("%s: ports %s, %s in use.", self, port, port + 1)
+        else:
+            assert False, "Should not reach this code execution point"
+
+    async def _connect_locked(self):
+        logging.debug("%s: connect to OSPF API", self)
+
+        loop = asyncio.get_event_loop()
+
+        self._ls.listen()
+        try:
+            logging.debug("%s: connecting sync socket to server", self)
+            await loop.sock_connect(self._s, (self.server, 2607))
+
+            logging.debug("%s: accepting connect from server", self)
+            self._as, _ = await loop.sock_accept(self._ls)
+        except Exception:
+            await self._close_locked()
+            raise
+
+        logging.debug("%s: success", self)
+        self._r, self._w = await asyncio.open_connection(sock=self._s)
+        self._ar, _ = await asyncio.open_connection(sock=self._as)
+        self._seq = 1
+
+    async def connect(self):
+        async with self.write_lock:
+            await self._connect_locked()
+
+    @property
+    def closed(self):
+        "True if the connection is closed."
+        return self._seq == 0
+
+    async def _close_locked(self):
+        logging.debug("%s: closing", self)
+        if self._s:
+            if self._w:
+                self._w.close()
+                await self._w.wait_closed()
+                self._w = None
+            else:
+                self._s.close()
+            self._s = None
+            self._r = None
+        assert self._w is None
+        if self._as:
+            self._as.close()
+            self._as = None
+            self._ar = None
+        if self._ls:
+            self._ls.close()
+            self._ls = None
+        self._seq = 0
+
+    async def close(self):
+        async with self.write_lock:
+            await self._close_locked()
+
+    @staticmethod
+    async def _msg_read(r, expseq=-1):
+        """Read an OSPF API message from the socket `r`
+
+        Args:
+            r: socket to read msg from
+            expseq: sequence number to expect or -1 for any.
+        Raises:
+            Will raise exceptions for failures with various `socket` modules,
+            Additionally may raise SeqNumError if unexpected seqnum is received.
+        """
+        try:
+            mh = await r.readexactly(FMT_APIMSGHDR_SIZE)
+            v, mt, l, seq = struct.unpack(FMT_APIMSGHDR, mh)
+            if v != 1:
+                raise Exception("received unexpected OSPF API version {}".format(v))
+            if expseq == -1:
+                logging.debug("_msg_read: got seq: 0x%x on async read", seq)
+            elif seq != expseq:
+                raise SeqNumError("rx {} != {}".format(seq, expseq))
+            msg = await r.readexactly(l) if l else b""
+            return mt, msg
+        except asyncio.IncompleteReadError:
+            raise EOFError
+
+    async def msg_read(self):
+        """Read a message from the async notify channel.
+
+        Raises:
+            May raise exceptions for failures with various `socket` modules.
+        """
+        return await OspfApiClient._msg_read(self._ar, -1)
+
+    async def msg_send(self, mt, mp):
+        """Send a message to OSPF API and wait for error code reply.
+
+        Args:
+            mt: the messaage type
+            mp: the message payload
+        Returns:
+            error: an OSPF_API_XXX error code, 0 for OK.
+        Raises:
+            Raises SeqNumError if the synchronous reply is the wrong sequence number;
+            MsgTypeError if the synchronous reply is not MSG_REPLY. Also,
+            may raise exceptions for failures with various `socket` modules,
+
+            The connection will be closed.
+        """
+        logging.debug("SEND: %s: sending %s seq 0x%x", self, api_msgname(mt), self._seq)
+        mh = struct.pack(FMT_APIMSGHDR, 1, mt, len(mp), self._seq)
+
+        seq = self._seq
+        self._seq = seq + 1
+
+        try:
+            async with self.write_lock:
+                self._w.write(mh + mp)
+                await self._w.drain()
+                mt, mp = await OspfApiClient._msg_read(self._r, seq)
+
+            if mt != MSG_REPLY:
+                raise MsgTypeError(
+                    "rx {} != {}".format(api_msgname(mt), api_msgname(MSG_REPLY))
+                )
+
+            return struct.unpack(msg_fmt[MSG_REPLY], mp)[0]
+        except Exception:
+            # We've written data with a sequence number
+            await self.close()
+            raise
+
+    async def msg_send_raises(self, mt, mp=b"\x00" * 4):
+        """Send a message to OSPF API and wait for error code reply.
+
+        Args:
+            mt: the messaage type
+            mp: the message payload
+        Raises:
+            APIError if the server replies with an error.
+
+            Also may raise exceptions for failures with various `socket` modules,
+            as well as MsgTypeError if the synchronous reply is incorrect.
+            The connection will be closed for these non-API error exceptions.
+        """
+        ecode = await self.msg_send(mt, mp)
+        if ecode:
+            raise APIError("{} error {}".format(api_msgname(mt), api_errname(ecode)))
+
+    async def handle_async_msg(self, mt, msg):
+        if mt not in msg_fmt:
+            logging.debug("RECV: %s: unknown async msg type %s", self, mt)
+            return
+
+        fmt = msg_fmt[mt]
+        sz = msg_size[mt]
+        tup = struct.unpack(fmt, msg[:sz])
+        extra = msg[sz:]
+
+        if mt not in self.handlers:
+            logging.debug(
+                "RECV: %s: no handlers for msg type %s", self, api_msgname(mt)
+            )
+            return
+
+        logging.debug("RECV: %s: calling handler for %s", self, api_msgname(mt))
+        await self.handlers[mt](mt, msg, extra, *tup)
+
+    #
+    # Client to Server Messaging
+    #
+    @staticmethod
+    def lsa_type_mask(*lsa_types):
+        "Return a 16 bit mask for each LSA type passed."
+        if not lsa_types:
+            return 0xFFFF
+        mask = 0
+        for t in lsa_types:
+            assert 0 < t < 16, "LSA type {} out of range [1, 15]".format(t)
+            mask |= 1 << t
+        return mask
+
+    @staticmethod
+    def lsa_filter(origin, areas, lsa_types):
+        """Return an LSA filter.
+
+        Return the filter message bytes based on `origin` the `areas` list and the LSAs
+        types in the `lsa_types` list.
+        """
+        mask = OspfApiClient.lsa_type_mask(*lsa_types)
+        narea = len(areas)
+        fmt = FMT_LSA_FILTER + ("{}I".format(narea) if narea else "")
+        # lsa type mask, origin, number of areas, each area
+        return struct.pack(fmt, mask, origin, narea, *areas)
+
+    async def req_lsdb_sync(self):
+        "Register for all LSA notifications and request an LSDB synchronoization."
+        logging.debug("SEND: %s: request LSDB events", self)
+        mp = OspfApiClient.lsa_filter(LSAF_ORIGIN_ANY, [], [])
+        await self.msg_send_raises(MSG_REGISTER_EVENT, mp)
+
+        logging.debug("SEND: %s: request LSDB sync", self)
+        await self.msg_send_raises(MSG_SYNC_LSDB, mp)
+
+    async def req_reachable_routers(self):
+        "Request a dump of all reachable routers."
+        logging.debug("SEND: %s: request reachable changes", self)
+        await self.msg_send_raises(MSG_SYNC_REACHABLE)
+
+    async def req_ism_states(self):
+        "Request a dump of the current ISM states of all interfaces."
+        logging.debug("SEND: %s: request ISM changes", self)
+        await self.msg_send_raises(MSG_SYNC_ISM)
+
+    async def req_nsm_states(self):
+        "Request a dump of the current NSM states of all neighbors."
+        logging.debug("SEND: %s: request NSM changes", self)
+        await self.msg_send_raises(MSG_SYNC_NSM)
+
+    async def req_router_id_sync(self):
+        "Request a dump of the current NSM states of all neighbors."
+        logging.debug("SEND: %s: request router ID sync", self)
+        await self.msg_send_raises(MSG_SYNC_ROUTER_ID)
+
+
+class OspfOpaqueClient(OspfApiClient):
+    """A client connection to OSPF Daemon for manipulating Opaque LSA data.
+
+    The client object is not created in a connected state.  To connect to the server
+    the `connect` method should be called.  If an error is encountered when sending
+    messages to the server an exception will be raised and the connection will be
+    closed.  When this happens `connect` may be called again to restore the
+    connection.
+
+    Args:
+        server: hostname or IP address of server default is "localhost"
+        wait_ready: if True then wait for OSPF to signal ready, in newer versions
+            FRR ospfd is always ready so this overhead can be skipped.
+            default is False.
+
+    Raises:
+        Will raise exceptions for failures with various `socket` modules
+        functions such as `socket.socket`, `socket.setsockopt`, `socket.bind`.
+    """
+
+    def __init__(self, server="localhost", wait_ready=False):
+        handlers = {
+            MSG_LSA_UPDATE_NOTIFY: self._lsa_change_msg,
+            MSG_LSA_DELETE_NOTIFY: self._lsa_change_msg,
+            MSG_NEW_IF: self._if_msg,
+            MSG_DEL_IF: self._if_msg,
+            MSG_ISM_CHANGE: self._if_change_msg,
+            MSG_NSM_CHANGE: self._nbr_change_msg,
+            MSG_REACHABLE_CHANGE: self._reachable_msg,
+            MSG_ROUTER_ID_CHANGE: self._router_id_msg,
+        }
+        if wait_ready:
+            handlers[MSG_READY_NOTIFY] = self._ready_msg
+
+        super().__init__(server, handlers)
+
+        self.wait_ready = wait_ready
+        self.ready_lock = Lock() if wait_ready else WithNothing()
+        self.ready_cond = {
+            LSA_TYPE_OPAQUE_LINK: {},
+            LSA_TYPE_OPAQUE_AREA: {},
+            LSA_TYPE_OPAQUE_AS: {},
+        }
+        self.router_id = ip(0)
+        self.router_id_change_cb = None
+
+        self.lsid_seq_num = {}
+
+        self.lsa_change_cb = None
+        self.opaque_change_cb = {}
+
+        self.reachable_routers = set()
+        self.reachable_change_cb = None
+
+        self.if_area = {}
+        self.ism_states = {}
+        self.ism_change_cb = None
+
+        self.nsm_states = {}
+        self.nsm_change_cb = None
+
+    async def _register_opaque_data(self, lsa_type, otype):
+        async with self.ready_lock:
+            cond = self.ready_cond[lsa_type].get(otype)
+            assert cond is None, "multiple registers for {} opaque-type {}".format(
+                lsa_typename(lsa_type), otype
+            )
+
+            logging.debug("register %s opaque-type %s", lsa_typename(lsa_type), otype)
+
+            mt = MSG_REGISTER_OPAQUETYPE
+            mp = struct.pack(msg_fmt[mt], lsa_type, otype)
+            await self.msg_send_raises(mt, mp)
+
+            # If we are not waiting, mark ready for register check
+            if not self.wait_ready:
+                self.ready_cond[lsa_type][otype] = True
+
+    async def _handle_msg_loop(self):
+        try:
+            logging.debug("entering async msg handling loop")
+            while True:
+                mt, msg = await self.msg_read()
+                if mt in amsg_info:
+                    await self.handle_async_msg(mt, msg)
+                else:
+                    mts = api_msgname(mt)
+                    logging.warning(
+                        "ignoring unexpected msg: %s len: %s", mts, len(msg)
+                    )
+        except EOFError:
+            logging.info("Got EOF from OSPF API server on async notify socket")
+            return 2
+
+    @staticmethod
+    def _opaque_args(lsa_type, otype, oid, mp):
+        lsid = (otype << 24) | oid
+        return 0, 0, lsa_type, lsid, 0, 0, 0, FMT_LSA_HEADER_SIZE + len(mp)
+
+    @staticmethod
+    def _make_opaque_lsa(lsa_type, otype, oid, mp):
+        # /* Make a new LSA from parameters */
+        lsa = struct.pack(
+            FMT_LSA_HEADER, *OspfOpaqueClient._opaque_args(lsa_type, otype, oid, mp)
+        )
+        lsa += mp
+        return lsa
+
+    async def _ready_msg(self, mt, msg, extra, lsa_type, otype, addr):
+        assert self.wait_ready
+
+        if lsa_type == LSA_TYPE_OPAQUE_LINK:
+            e = "ifaddr {}".format(ip(addr))
+        elif lsa_type == LSA_TYPE_OPAQUE_AREA:
+            e = "area {}".format(ip(addr))
+        else:
+            e = ""
+        logging.info(
+            "RECV: %s ready notify for %s opaque-type %s%s",
+            self,
+            lsa_typename(lsa_type),
+            otype,
+            e,
+        )
+
+        # Signal all waiting senders they can send now.
+        async with self.ready_lock:
+            cond = self.ready_cond[lsa_type].get(otype)
+            self.ready_cond[lsa_type][otype] = True
+
+        if cond is True:
+            logging.warning(
+                "RECV: dup ready received for %s opaque-type %s",
+                lsa_typename(lsa_type),
+                otype,
+            )
+        elif cond:
+            for evt in cond:
+                evt.set()
+
+    async def _if_msg(self, mt, msg, extra, *args):
+        if mt == MSG_NEW_IF:
+            ifaddr, aid = args
+        else:
+            assert mt == MSG_DEL_IF
+            ifaddr, aid = args[0], 0
+        logging.info(
+            "RECV: %s ifaddr %s areaid %s", api_msgname(mt), ip(ifaddr), ip(aid)
+        )
+
+    async def _if_change_msg(self, mt, msg, extra, ifaddr, aid, state):
+        ifaddr = ip(ifaddr)
+        aid = ip(aid)
+
+        logging.info(
+            "RECV: %s ifaddr %s areaid %s state %s",
+            api_msgname(mt),
+            ifaddr,
+            aid,
+            ism_name(state),
+        )
+
+        self.if_area[ifaddr] = aid
+        self.ism_states[ifaddr] = state
+
+        if self.ism_change_cb:
+            self.ism_change_cb(ifaddr, aid, state)
+
+    async def _nbr_change_msg(self, mt, msg, extra, ifaddr, nbraddr, router_id, state):
+        ifaddr = ip(ifaddr)
+        nbraddr = ip(nbraddr)
+        router_id = ip(router_id)
+
+        logging.info(
+            "RECV: %s ifaddr %s nbraddr %s router_id %s state %s",
+            api_msgname(mt),
+            ifaddr,
+            nbraddr,
+            router_id,
+            nsm_name(state),
+        )
+
+        if ifaddr not in self.nsm_states:
+            self.nsm_states[ifaddr] = {}
+        self.nsm_states[ifaddr][(nbraddr, router_id)] = state
+
+        if self.nsm_change_cb:
+            self.nsm_change_cb(ifaddr, nbraddr, router_id, state)
+
+    async def _lsa_change_msg(self, mt, msg, extra, ifaddr, aid, is_self, *ls_header):
+        (
+            lsa_age,  # ls_age,
+            _,  # ls_options,
+            lsa_type,
+            ls_id,
+            _,  # ls_adv_router,
+            ls_seq,
+            _,  # ls_cksum,
+            ls_len,
+        ) = ls_header
+
+        otype = (ls_id >> 24) & 0xFF
+
+        if mt == MSG_LSA_UPDATE_NOTIFY:
+            ts = "update"
+        else:
+            assert mt == MSG_LSA_DELETE_NOTIFY
+            ts = "delete"
+
+        logging.info(
+            "RECV: LSA %s msg for LSA %s in area %s seq 0x%x len %s age %s",
+            ts,
+            ip(ls_id),
+            ip(aid),
+            ls_seq,
+            ls_len,
+            lsa_age,
+        )
+        idx = (lsa_type, otype)
+
+        pre_lsa_size = msg_size[mt] - FMT_LSA_HEADER_SIZE
+        lsa = msg[pre_lsa_size:]
+
+        if idx in self.opaque_change_cb:
+            self.opaque_change_cb[idx](mt, ifaddr, aid, ls_header, extra, lsa)
+
+        if self.lsa_change_cb:
+            self.lsa_change_cb(mt, ifaddr, aid, ls_header, extra, lsa)
+
+    async def _reachable_msg(self, mt, msg, extra, nadd, nremove):
+        router_ids = struct.unpack(">{}I".format(nadd + nremove), extra)
+        router_ids = [ip(x) for x in router_ids]
+        logging.info(
+            "RECV: %s added %s removed %s",
+            api_msgname(mt),
+            router_ids[:nadd],
+            router_ids[nadd:],
+        )
+        self.reachable_routers |= set(router_ids[:nadd])
+        self.reachable_routers -= set(router_ids[nadd:])
+        logging.info("RECV: %s new set %s", api_msgname(mt), self.reachable_routers)
+
+        if self.reachable_change_cb:
+            logging.info("RECV: %s calling callback", api_msgname(mt))
+            await self.reachable_change_cb(router_ids[:nadd], router_ids[nadd:])
+
+    async def _router_id_msg(self, mt, msg, extra, router_id):
+        router_id = ip(router_id)
+        logging.info("RECV: %s router ID %s", api_msgname(mt), router_id)
+        old_router_id = self.router_id
+        if old_router_id == router_id:
+            return
+
+        self.router_id = router_id
+        logging.info(
+            "RECV: %s new router ID %s older router ID %s",
+            api_msgname(mt),
+            router_id,
+            old_router_id,
+        )
+
+        if self.router_id_change_cb:
+            logging.info("RECV: %s calling callback", api_msgname(mt))
+            await self.router_id_change_cb(router_id, old_router_id)
+
+    async def add_opaque_data(self, addr, lsa_type, otype, oid, data):
+        """Add an instance of opaque data.
+
+        Add an instance of opaque data. This call will register for the given
+        LSA and opaque type if not already done.
+
+        Args:
+            addr: depends on lsa_type, LINK => ifaddr, AREA => area ID, AS => ignored
+            lsa_type: LSA_TYPE_OPAQUE_{LINK,AREA,AS}
+            otype: (octet) opaque type
+            oid: (3 octets) ID of this opaque data
+            data: the opaque data
+        Raises:
+            See `msg_send_raises`
+        """
+        assert self.ready_cond.get(lsa_type, {}).get(otype) is True, "Not Registered!"
+
+        if lsa_type == LSA_TYPE_OPAQUE_LINK:
+            ifaddr, aid = int(addr), 0
+        elif lsa_type == LSA_TYPE_OPAQUE_AREA:
+            ifaddr, aid = 0, int(addr)
+        else:
+            assert lsa_type == LSA_TYPE_OPAQUE_AS
+            ifaddr, aid = 0, 0
+
+        mt = MSG_ORIGINATE_REQUEST
+        msg = struct.pack(
+            msg_fmt[mt],
+            ifaddr,
+            aid,
+            *OspfOpaqueClient._opaque_args(lsa_type, otype, oid, data),
+        )
+        msg += data
+        await self.msg_send_raises(mt, msg)
+
+    async def delete_opaque_data(self, addr, lsa_type, otype, oid, flags=0):
+        """Delete an instance of opaque data.
+
+        Delete an instance of opaque data. This call will register for the given
+        LSA and opaque type if not already done.
+
+        Args:
+            addr: depends on lsa_type, LINK => ifaddr, AREA => area ID, AS => ignored
+            lsa_type: LSA_TYPE_OPAQUE_{LINK,AREA,AS}
+            otype: (octet) opaque type.
+            oid: (3 octets) ID of this opaque data
+            flags: (octet) optional flags (e.g., OSPF_API_DEL_ZERO_LEN_LSA, defaults to no flags)
+        Raises:
+            See `msg_send_raises`
+        """
+        assert self.ready_cond.get(lsa_type, {}).get(otype) is True, "Not Registered!"
+
+        mt = MSG_DELETE_REQUEST
+        mp = struct.pack(msg_fmt[mt], int(addr), lsa_type, otype, flags, oid)
+        await self.msg_send_raises(mt, mp)
+
+    async def is_registered(self, lsa_type, otype):
+        """Determine if an (lsa_type, otype) tuple has been registered with FRR
+
+        This determines if the type has been registered, but not necessarily if it is
+        ready, if that is required use the `wait_opaque_ready` metheod.
+
+        Args:
+            lsa_type: LSA_TYPE_OPAQUE_{LINK,AREA,AS}
+            otype: (octet) opaque type.
+        """
+        async with self.ready_lock:
+            return self.ready_cond.get(lsa_type, {}).get(otype) is not None
+
+    async def register_opaque_data(self, lsa_type, otype, callback=None):
+        """Register intent to advertise opaque data.
+
+        The application should wait for the async notificaiton that the server is
+        ready to advertise the given opaque data type. The API currently only allows
+        a single "owner" of each unique (lsa_type,otype). To wait call `wait_opaque_ready`
+
+        Args:
+            lsa_type: LSA_TYPE_OPAQUE_{LINK,AREA,AS}
+            otype: (octet) opaque type.
+            callback: if given, callback will be called when changes are received for
+                LSA of the given (lsa_type, otype). The callbacks signature is:
+
+                `callback(msg_type, ifaddr, area_id, lsa_header, data, lsa)`
+
+                Args:
+                    msg_type: MSG_LSA_UPDATE_NOTIFY or MSG_LSA_DELETE_NOTIFY
+                    ifaddr: integer identifying an interface (by IP address)
+                    area_id: integer identifying an area
+                    lsa_header: the LSA header as an unpacked tuple (fmt: ">HBBIILHH")
+                    data: the opaque data that follows the LSA header
+                    lsa: the octets of the full lsa
+        Raises:
+            See `msg_send_raises`
+        """
+        assert not await self.is_registered(
+            lsa_type, otype
+        ), "Registering registered type"
+
+        if callback:
+            self.opaque_change_cb[(lsa_type, otype)] = callback
+        elif (lsa_type, otype) in self.opaque_change_cb:
+            logging.warning(
+                "OSPFCLIENT: register: removing callback for %s opaque-type %s",
+                lsa_typename(lsa_type),
+                otype,
+            )
+            del self.opaque_change_cb[(lsa_type, otype)]
+
+        await self._register_opaque_data(lsa_type, otype)
+
+    async def wait_opaque_ready(self, lsa_type, otype):
+        async with self.ready_lock:
+            cond = self.ready_cond[lsa_type].get(otype)
+            if cond is True:
+                return
+
+            assert self.wait_ready
+
+            logging.debug(
+                "waiting for ready %s opaque-type %s", lsa_typename(lsa_type), otype
+            )
+
+            if not cond:
+                cond = self.ready_cond[lsa_type][otype] = []
+
+            evt = Event()
+            cond.append(evt)
+
+        await evt.wait()
+        logging.debug("READY for %s opaque-type %s", lsa_typename(lsa_type), otype)
+
+    async def register_opaque_data_wait(self, lsa_type, otype, callback=None):
+        """Register intent to advertise opaque data and wait for ready.
+
+        The API currently only allows a single "owner" of each unique (lsa_type,otype).
+
+        Args:
+            lsa_type: LSA_TYPE_OPAQUE_{LINK,AREA,AS}
+            otype: (octet) opaque type.
+            callback: if given, callback will be called when changes are received for
+                LSA of the given (lsa_type, otype). The callbacks signature is:
+
+                `callback(msg_type, ifaddr, area_id, lsa_header, data, lsa)`
+
+                Args:
+                    msg_type: MSG_LSA_UPDATE_NOTIFY or MSG_LSA_DELETE_NOTIFY
+                    ifaddr: integer identifying an interface (by IP address)
+                    area_id: integer identifying an area
+                    lsa_header: the LSA header as an unpacked tuple (fmt: ">HBBIILHH")
+                    data: the opaque data that follows the LSA header
+                    lsa: the octets of the full lsa
+        Raises:
+
+            See `msg_send_raises`
+        """
+        await self.register_opaque_data(lsa_type, otype, callback)
+        await self.wait_opaque_ready(lsa_type, otype)
+
+    async def unregister_opaque_data(self, lsa_type, otype):
+        """Unregister intent to advertise opaque data.
+
+        This will also cause the server to flush/delete all opaque data of
+        the given (lsa_type,otype).
+
+        Args:
+            lsa_type: LSA_TYPE_OPAQUE_{LINK,AREA,AS}
+            otype: (octet) opaque type.
+        Raises:
+            See `msg_send_raises`
+        """
+        assert await self.is_registered(
+            lsa_type, otype
+        ), "Unregistering unregistered type"
+
+        if (lsa_type, otype) in self.opaque_change_cb:
+            del self.opaque_change_cb[(lsa_type, otype)]
+
+        mt = MSG_UNREGISTER_OPAQUETYPE
+        mp = struct.pack(msg_fmt[mt], lsa_type, otype)
+        await self.msg_send_raises(mt, mp)
+
+    async def monitor_lsa(self, callback=None):
+        """Monitor changes to LSAs.
+
+        Args:
+            callback: if given, callback will be called when changes are received for
+                any LSA. The callback signature is:
+
+                `callback(msg_type, ifaddr, area_id, lsa_header, extra, lsa)`
+
+                Args:
+                    msg_type: MSG_LSA_UPDATE_NOTIFY or MSG_LSA_DELETE_NOTIFY
+                    ifaddr: integer identifying an interface (by IP address)
+                    area_id: integer identifying an area
+                    lsa_header: the LSA header as an unpacked tuple (fmt: ">HBBIILHH")
+                    extra: the octets that follow the LSA header
+                    lsa: the octets of the full lsa
+        """
+        self.lsa_change_cb = callback
+        await self.req_lsdb_sync()
+
+    async def monitor_reachable(self, callback=None):
+        """Monitor the set of reachable routers.
+
+        The property `reachable_routers` contains the set() of reachable router IDs
+        as integers. This set is updated prior to calling the `callback`
+
+        Args:
+            callback: callback will be called when the set of reachable
+                routers changes. The callback signature is:
+
+                `callback(added, removed)`
+
+                Args:
+                    added: list of integer router IDs being added
+                    removed: list of integer router IDs being removed
+        """
+        self.reachable_change_cb = callback
+        await self.req_reachable_routers()
+
+    async def monitor_ism(self, callback=None):
+        """Monitor the state of OSPF enabled interfaces.
+
+        Args:
+            callback: callback will be called when an interface changes state.
+                The callback signature is:
+
+                `callback(ifaddr, area_id, state)`
+
+                Args:
+                    ifaddr: integer identifying an interface (by IP address)
+                    area_id: integer identifying an area
+                    state: ISM_*
+        """
+        self.ism_change_cb = callback
+        await self.req_ism_states()
+
+    async def monitor_nsm(self, callback=None):
+        """Monitor the state of OSPF neighbors.
+
+        Args:
+            callback: callback will be called when a neighbor changes state.
+                The callback signature is:
+
+                `callback(ifaddr, nbr_addr, router_id, state)`
+
+                Args:
+                    ifaddr: integer identifying an interface (by IP address)
+                    nbr_addr: integer identifying neighbor by IP address
+                    router_id: integer identifying neighbor router ID
+                    state: NSM_*
+        """
+        self.nsm_change_cb = callback
+        await self.req_nsm_states()
+
+    async def monitor_router_id(self, callback=None):
+        """Monitor the OSPF router ID.
+
+        The property `router_id` contains the OSPF urouter ID.
+        This value is updated prior to calling the `callback`
+
+        Args:
+            callback: callback will be called when the router ID changes.
+                The callback signature is:
+
+                `callback(new_router_id, old_router_id)`
+
+                Args:
+                    new_router_id: the new router ID
+                    old_router_id: the old router ID
+        """
+        self.router_id_change_cb = callback
+        await self.req_router_id_sync()
+
+
+# ================
+# CLI/Script Usage
+# ================
+def next_action(action_list=None):
+    "Get next action from list or STDIN"
+    if action_list:
+        for action in action_list:
+            yield action
+    else:
+        while True:
+            action = input("")
+            if not action:
+                break
+            yield action.strip()
+
+
+async def async_main(args):
+    c = OspfOpaqueClient(args.server)
+    await c.connect()
+
+    try:
+        # Start handling async messages from server.
+        if sys.version_info[1] > 6:
+            asyncio.create_task(c._handle_msg_loop())
+        else:
+            asyncio.get_event_loop().create_task(c._handle_msg_loop())
+
+        await c.req_lsdb_sync()
+        await c.req_reachable_routers()
+        await c.req_ism_states()
+        await c.req_nsm_states()
+
+        for action in next_action(args.actions):
+            _s = action.split(",")
+            what = _s.pop(False)
+            if what.casefold() == "wait":
+                stime = int(_s.pop(False))
+                logging.info("waiting %s seconds", stime)
+                await asyncio.sleep(stime)
+                logging.info("wait complete: %s seconds", stime)
+                continue
+            ltype = int(_s.pop(False))
+            if ltype == 11:
+                addr = ip(0)
+            else:
+                aval = _s.pop(False)
+                try:
+                    addr = ip(int(aval))
+                except ValueError:
+                    addr = ip(aval)
+            oargs = [addr, ltype, int(_s.pop(False)), int(_s.pop(False))]
+
+            if not await c.is_registered(oargs[1], oargs[2]):
+                await c.register_opaque_data_wait(oargs[1], oargs[2])
+
+            if what.casefold() == "add":
+                try:
+                    b = bytes.fromhex(_s.pop(False))
+                except IndexError:
+                    b = b""
+                logging.info("opaque data is %s octets", len(b))
+                # Needs to be multiple of 4 in length
+                mod = len(b) % 4
+                if mod:
+                    b += b"\x00" * (4 - mod)
+                    logging.info("opaque padding to %s octets", len(b))
+
+                await c.add_opaque_data(*oargs, b)
+            else:
+                assert what.casefold().startswith("del")
+                f = 0
+                if len(_s) >= 1:
+                    try:
+                        f = int(_s.pop(False))
+                    except IndexError:
+                        f = 0
+                await c.delete_opaque_data(*oargs, f)
+        if not args.actions or args.exit:
+            return 0
+    except Exception as error:
+        logging.error("async_main: unexpected error: %s", error, exc_info=True)
+        return 2
+
+    try:
+        logging.info("Sleeping forever")
+        while True:
+            await asyncio.sleep(120)
+    except EOFError:
+        logging.info("Got EOF from OSPF API server on async notify socket")
+        return 2
+
+
+def main(*args):
+    ap = argparse.ArgumentParser(args)
+    ap.add_argument("--logtag", default="CLIENT", help="tag to identify log messages")
+    ap.add_argument("--exit", action="store_true", help="Exit after commands")
+    ap.add_argument("--server", default="localhost", help="OSPF API server")
+    ap.add_argument("-v", "--verbose", action="store_true", help="be verbose")
+    ap.add_argument(
+        "actions",
+        nargs="*",
+        help="WAIT,SEC|(ADD|DEL),LSATYPE,[ADDR,],OTYPE,OID,[HEXDATA|DEL_FLAG]",
+    )
+    args = ap.parse_args()
+
+    level = logging.DEBUG if args.verbose else logging.INFO
+    logging.basicConfig(
+        level=level,
+        format="%(asctime)s %(levelname)s: {}: %(name)s %(message)s".format(
+            args.logtag
+        ),
+    )
+
+    logging.info("ospfclient: starting")
+
+    status = 3
+    try:
+        if sys.version_info[1] > 6:
+            # python >= 3.7
+            status = asyncio.run(async_main(args))
+        else:
+            loop = asyncio.get_event_loop()
+            try:
+                status = loop.run_until_complete(async_main(args))
+            finally:
+                loop.close()
+    except KeyboardInterrupt:
+        logging.info("Exiting, received KeyboardInterrupt in main")
+    except Exception as error:
+        logging.info("Exiting, unexpected exception %s", error, exc_info=True)
+    else:
+        logging.info("ospfclient: clean exit")
+
+    return status
+
+
+if __name__ == "__main__":
+    exit_status = main()
+    sys.exit(exit_status)
diff --git a/ospfclient/subdir.am b/ospfclient/subdir.am
new file mode 100644
index 0000000..289ddd0
--- /dev/null
+++ b/ospfclient/subdir.am
@@ -0,0 +1,52 @@
+#
+# ospfclient
+#
+
+if OSPFCLIENT
+lib_LTLIBRARIES += ospfclient/libfrrospfapiclient.la
+noinst_PROGRAMS += ospfclient/ospfclient
+#man8 += $(MANBUILD)/frr-ospfclient.8
+
+sbin_SCRIPTS += \
+	ospfclient/ospfclient.py \
+	# end
+endif
+
+ospfclient_libfrrospfapiclient_la_LDFLAGS = $(LIB_LDFLAGS) -version-info 0:0:0
+ospfclient_libfrrospfapiclient_la_LIBADD = lib/libfrr.la
+ospfclient_libfrrospfapiclient_la_SOURCES = \
+	ospfclient/ospf_apiclient.c \
+	# end
+
+if OSPFCLIENT
+ospfapiheaderdir = $(pkgincludedir)/ospfapi
+ospfapiheader_HEADERS = \
+	ospfclient/ospf_apiclient.h \
+	# end
+endif
+
+ospfclient_ospfclient_LDADD = \
+	ospfclient/libfrrospfapiclient.la \
+	ospfd/libfrrospfclient.a \
+	$(LIBCAP) \
+	# end
+
+if STATIC_BIN
+# libfrr is linked in through libfrrospfapiclient.  If we list it here too,
+# it gets linked twice and we get a ton of symbol collisions.
+
+else # !STATIC_BIN
+# For most systems we don't need this, except Debian, who patch their linker
+# to disallow transitive references *while* *als* not patching their libtool
+# to work appropriately.  RedHat has the same linker behaviour, but things
+# work as expected since they also patch libtool.
+ospfclient_ospfclient_LDADD += lib/libfrr.la
+endif
+
+ospfclient_ospfclient_SOURCES = \
+	ospfclient/ospfclient.c \
+	# end
+
+EXTRA_DIST += \
+	ospfclient/ospfclient.py \
+	# end