o Add a collection of regression tests for ancillary (control)

data passing for unix domain sockets, stream and datagram.

There are 15 tests:

Test/Type of socket					STREAM	DGRAM
----------------------------------------------------------------------
Sending, receiving cmsgcred				   1      6
Receiving sockcred (listening socket has LOCAL_CREDS)	   2      n/a
Receiving sockcred (accepted socket has LOCAL_CREDS)	   3      n/a
Receiving sockcred					   n/a    7
Sending cmsgcred, receiving sockcred			   4      8
Sending, receiving timestamp				   5      9
Sending, receiving cmsgcred (no control data)		   10     13
Sending cmsgcred, receiving sockcred (no control data)	   11     14
Sending, receiving timestamp (no control data)		   12     15

Currently we pass 8 tests.  All the rest marked as TODO.

PR:		kern/90800
Submitted by:	Andrey Simonenko

tools/regression/sockets/unix_cmsg/Makefile

@@ -0,0 +1,7 @@
+# $FreeBSD$
+
+PROG=	unix_cmsg
+NO_MAN=
+WARNS?=	3
+
+.include <bsd.prog.mk>

tools/regression/sockets/unix_cmsg/README

@@ -0,0 +1,127 @@
+$FreeBSD$
+
+About unix_cmsg
+================
+
+This program is a collection of regression tests for ancillary (control)
+data for PF_LOCAL sockets (local domain or Unix domain sockets).  There
+are tests for stream and datagram sockets.
+
+Usually each test does following steps: create Server, fork Client,
+Client sends something to Server, Server verifies if everything
+is correct in received message.  Sometimes Client sends several
+messages to Server.
+
+It is better to change the owner of unix_cmsg to some safe user
+(eg. nobody:nogroup) and set SUID and SGID bits, else some tests
+can give correct results for wrong implementation.
+
+Available options
+=================
+
+-d	Output debugging information, values of different fields of
+	received messages, etc.  Will produce many lines of information.
+
+-h	Output help message and exit.
+
+-t <socktype>
+	Run tests only for the given socket type: "stream" or "dgram".
+	With this option it is possible to run only particular test,
+	not all of them.
+
+-z	Do not send real control data if possible.  Struct cmsghdr{}
+	should be followed by real control data.  It is not clear if
+	a sender should give control data in all cases (this is not
+	documented and an arbitrary application can choose anything).
+
+	At least for PF_LOCAL sockets' control messages with types
+	SCM_CREDS and SCM_TIMESTAMP the kernel does not need any
+	control data.  This option allow to not send real control data
+	for SCM_CREDS and SCM_TIMESTAMP control messages.
+
+Description of tests
+====================
+
+For SOCK_STREAM sockets:
+-----------------------
+
+ 1: Sending, receiving cmsgcred
+
+    Client connects to Server and sends two messages with data and
+    control message with SCM_CREDS type to Server.  Server should
+    receive two messages, in both messages there should be data and
+    control message with SCM_CREDS type followed by struct cmsgcred{}
+    and this structure should contain correct information.
+
+ 2: Receiving sockcred (listening socket has LOCAL_CREDS)
+
+    Server creates listen socket and set socket option LOCAL_CREDS
+    for it.  Client connects to Server and sends two messages with data
+    to Server.  Server should receive two messages, in first message
+    there should be data and control message with SCM_CREDS type followed
+    by struct sockcred{} and this structure should contain correct
+    information, in second message there should be data and no control
+    message.
+
+ 3: Receiving sockcred (accepted socket has LOCAL_CREDS)
+
+    Client connects to Server and sends two messages with data.  Server
+    accepts connection and set socket option LOCAL_CREDS for just accepted
+    socket (here synchronization is used, to allow Client to see just set
+    flag on Server's socket before sending messages to Server).  Server
+    should receive two messages, in first message there should be data and
+    control message with SOCK_CRED type followed by struct sockcred{} and
+    this structure should contain correct information, in second message
+    there should be data and no control message.
+
+ 4: Sending cmsgcred, receiving sockcred
+
+    Server creates listen socket and set socket option LOCAL_CREDS
+    for it.  Client connects to Server and sends one message with data
+    and control message with SCM_CREDS type to Server.  Server should
+    receive one message with data and control message with SCM_CREDS type
+    followed by struct sockcred{} and this structure should contain
+    correct information.
+
+ 5: Sending, receiving timestamp
+
+    Client connects to Server and sends message with data and control
+    message with SCM_TIMESTAMP type to Server.  Server should receive
+    message with data and control message with SCM_TIMESTAMP type
+    followed by struct timeval{}.
+
+For SOCK_DGRAM sockets:
+----------------------
+
+ 1: Sending, receiving cmsgcred
+
+    Client sends to Server two messages with data and control message
+    with SCM_CREDS type to Server.  Server should receive two messages,
+    in both messages there should be data and control message with
+    SCM_CREDS type followed by struct cmsgcred{} and this structure
+    should contain correct information.
+
+ 2: Receiving sockcred
+
+    Server creates datagram socket and set socket option LOCAL_CREDS
+    for it.  Client sends two messages with data to Server.  Server should
+    receive two messages, in both messages there should be data and control
+    message with SCM_CREDS type followed by struct sockcred{} and this
+    structure should contain correct information.
+
+ 3: Sending cmsgcred, receiving sockcred
+ 
+    Server creates datagram socket and set socket option LOCAL_CREDS
+    for it.  Client sends one message with data and control message with
+    SOCK_CREDS type to Server.  Server should receive one message with
+    data and control message with SCM_CREDS type followed by struct
+    sockcred{} and this structure should contain correct information.
+
+ 4: Sending, receiving timestamp
+
+    Client sends message with data and control message with SCM_TIMESTAMP
+    type to Server.  Server should receive message with data and control
+    message with SCM_TIMESTAMP type followed by struct timeval{}.
+
+- Andrey Simonenko
+simon@comsys.ntu-kpi.kiev.ua

tools/regression/sockets/unix_cmsg/unix_cmsg.t

@@ -0,0 +1,57 @@
+#!/bin/sh
+# $FreeBSD$
+
+cd `dirname $0`
+cmd="./`basename $0 .t`"
+
+make ${cmd} >/dev/null 2>&1
+
+IFS=
+n=0
+
+run()
+{
+	result=`${cmd} -t $2 $3 $4 2>&1`
+	if [ $? -eq 0 ]; then
+		echo -n "ok $1"
+	else
+		echo -n "not ok $1"
+	fi
+	echo " -" $5
+	echo ${result} | grep -E "SERVER|CLIENT" | while read line; do
+		echo "# ${line}"
+	done
+}
+
+echo "1..15"
+
+for desc in \
+	"Sending, receiving cmsgcred" \
+	"Receiving sockcred (listening socket has LOCAL_CREDS) # TODO" \
+	"Receiving sockcred (accepted socket has LOCAL_CREDS) # TODO" \
+	"Sending cmsgcred, receiving sockcred # TODO" \
+	"Sending, receiving timestamp"
+do
+	n=`expr ${n} + 1`
+	run ${n} stream "" ${n} "STREAM ${desc}"
+done
+
+i=0
+for desc in \
+	"Sending, receiving cmsgcred" \
+	"Receiving sockcred # TODO" \
+	"Sending cmsgcred, receiving sockcred # TODO" \
+	"Sending, receiving timestamp"
+do
+	i=`expr ${i} + 1`
+	n=`expr ${n} + 1`
+	run ${n} dgram "" ${i} "DGRAM ${desc}"
+done
+
+run 10 stream -z 1 "STREAM Sending, receiving cmsgcred (no control data)"
+run 11 stream -z 4 "STREAM Sending cmsgcred, receiving sockcred (no control data) # TODO"
+run 12 stream -z 5 "STREAM Sending, receiving timestamp (no control data)"
+
+run 13 dgram -z 1 "DGRAM Sending, receiving cmsgcred (no control data)"
+run 14 dgram -z 3 "DGRAM Sending cmsgcred, receiving sockcred (no control data) # TODO"
+run 15 dgram -z 4 "DGRAM Sending, receiving timestamp (no control data)"