[master] Merge branch 'trac3186' DHCP hook library user_chk

Adds the hooks subdirectory to bind10/dir for storing hooks shared
libraries, and the first such library for DHCP, user_chk.

configure.ac

@@ -1288,6 +1288,10 @@ AC_CONFIG_FILES([Makefile
                  src/bin/usermgr/Makefile
                  src/bin/usermgr/tests/Makefile
                  src/bin/tests/Makefile
+                 src/hooks/Makefile
+                 src/hooks/dhcp/Makefile
+                 src/hooks/dhcp/user_chk/Makefile
+                 src/hooks/dhcp/user_chk/tests/Makefile
                  src/lib/Makefile
                  src/lib/asiolink/Makefile
                  src/lib/asiolink/tests/Makefile
@@ -1468,6 +1472,7 @@ AC_OUTPUT([doc/version.ent
            src/bin/d2/spec_config.h.pre
            src/bin/d2/tests/test_data_files_config.h
            src/bin/tests/process_rename_test.py
+           src/hooks/dhcp/user_chk/tests/test_data_files_config.h
            src/lib/config/tests/data_def_unittests_config.h
            src/lib/dhcpsrv/tests/test_libraries.h
            src/lib/python/isc/config/tests/config_test

src/Makefile.am

 SUBDIRS = lib bin
+# @todo hooks lib could be a configurable switch
+SUBDIRS += hooks
 
 EXTRA_DIST = \
 	cppcheck-suppress.lst		\

src/hooks/Makefile.am

+SUBDIRS = dhcp

src/hooks/dhcp/Makefile.am

+SUBDIRS = user_chk

src/hooks/dhcp/user_chk/Makefile.am

+SUBDIRS = . tests
+
+AM_CPPFLAGS  = -I$(top_builddir)/src/lib -I$(top_srcdir)/src/lib
+AM_CPPFLAGS += $(BOOST_INCLUDES)
+AM_CXXFLAGS  = $(B10_CXXFLAGS)
+
+# Some versions of GCC warn about some versions of Boost regarding
+# missing initializer for members in its posix_time.
+# https://svn.boost.org/trac/boost/ticket/3477
+# But older GCC compilers don't have the flag.
+AM_CXXFLAGS += $(WARNING_NO_MISSING_FIELD_INITIALIZERS_CFLAG)
+
+# Define rule to build logging source files from message file
+user_chk_messages.h user_chk_messages.cc: s-messages
+
+s-messages: user_chk_messages.mes
+	$(top_builddir)/src/lib/log/compiler/message $(top_srcdir)/src/hooks/dhcp/user_chk/user_chk_messages.mes
+	touch $@
+
+# Tell automake that the message files are built as part of the build process
+# (so that they are built before the main library is built).
+BUILT_SOURCES = user_chk_messages.h user_chk_messages.cc
+
+# Ensure that the message file is included in the distribution
+EXTRA_DIST =
+
+# Get rid of generated message files on a clean
+CLEANFILES = *.gcno *.gcda user_chk_messages.h user_chk_messages.cc s-messages
+
+lib_LTLIBRARIES = libdhcp_user_chk.la
+libdhcp_user_chk_la_SOURCES  =
+libdhcp_user_chk_la_SOURCES += load_unload.cc
+libdhcp_user_chk_la_SOURCES += subnet_select_co.cc
+libdhcp_user_chk_la_SOURCES += user.cc user.h
+libdhcp_user_chk_la_SOURCES += user_chk_log.cc user_chk_log.h
+libdhcp_user_chk_la_SOURCES += user_data_source.h
+libdhcp_user_chk_la_SOURCES += user_file.cc user_file.h
+libdhcp_user_chk_la_SOURCES += user_registry.cc user_registry.h
+libdhcp_user_chk_la_SOURCES += version.cc
+
+# Until logging in dynamically loaded libraries is fixed, exclude these.
+#nodist_libdhcp_user_chk_la_SOURCES = user_chk_messages.cc user_chk_messages.h
+
+libdhcp_user_chk_la_CXXFLAGS = $(AM_CXXFLAGS)
+libdhcp_user_chk_la_CPPFLAGS = $(AM_CPPFLAGS) $(LOG4CPLUS_INCLUDES)
+libdhcp_user_chk_la_LDFLAGS  = $(AM_LDFLAGS)
+libdhcp_user_chk_la_LDFLAGS  += -avoid-version -export-dynamic -module
+libdhcp_user_chk_la_LIBADD  =
+libdhcp_user_chk_la_LIBADD  += $(top_builddir)/src/lib/hooks/libb10-hooks.la
+libdhcp_user_chk_la_LIBADD  += $(top_builddir)/src/lib/log/libb10-log.la
+libdhcp_user_chk_la_LIBADD  += $(top_builddir)/src/lib/exceptions/libb10-exceptions.la
+libdhcp_user_chk_la_LIBADD  += $(top_builddir)/src/lib/util/libb10-util.la
+libdhcp_user_chk_la_LIBADD  += $(top_builddir)/src/lib/util/threads/libb10-threads.la
+
+
+if USE_CLANGPP
+# Disable unused parameter warning caused by some of the
+# Boost headers when compiling with clang.
+libdhcp_user_chk_la_CXXFLAGS += -Wno-unused-parameter
+endif

src/hooks/dhcp/user_chk/load_unload.cc

+// Copyright (C) 2013 Internet Systems Consortium, Inc. ("ISC")
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+/// @file This file defines the load and unload hooks library functions.
+
+#include <hooks/hooks.h>
+#include <user_registry.h>
+#include <user_file.h>
+
+#include <iostream>
+#include <fstream>
+#include <errno.h>
+
+using namespace isc::hooks;
+
+/// @brief Pointer to the registry instance.
+UserRegistryPtr user_registry;
+
+/// @brief Output filestream for recording user check outcomes.
+std::fstream user_chk_output;
+
+/// @brief User registry input file name.
+/// @todo Hard-coded for now, this should be configurable.
+const char* registry_fname = "/tmp/user_chk_registry.txt";
+
+/// @brief User check outcome file name.
+/// @todo Hard-coded for now, this should be configurable.
+const char* user_chk_output_fname = "/tmp/user_chk_outcome.txt";
+
+// Functions accessed by the hooks framework use C linkage to avoid the name
+// mangling that accompanies use of the C++ compiler as well as to avoid
+// issues related to namespaces.
+extern "C" {
+
+/// @brief Called by the Hooks library manager when the library is loaded.
+///
+/// Instantiates the UserRegistry and opens the outcome file. Failure in
+/// either results in a failed return code.
+///
+/// @param unused library handle parameter required by Hooks API.
+///
+/// @return Returns 0 upon success, non-zero upon failure.
+int load(LibraryHandle&) {
+    // non-zero indicates an error.
+    int ret_val = 0;
+    try {
+        // Instantiate the registry.
+        user_registry.reset(new UserRegistry());
+
+        // Create the data source.
+        UserDataSourcePtr user_file(new UserFile(registry_fname));
+
+        // Set the registry's data source
+        user_registry->setSource(user_file);
+
+        // Do an initial load of the registry.
+        user_registry->refresh();
+
+        // Open up the output file for user_chk results.
+        user_chk_output.open(user_chk_output_fname,
+                     std::fstream::out | std::fstream::app);
+
+        if (!user_chk_output) {
+            // Grab the system error message.
+            const char* errmsg = strerror(errno);
+            isc_throw(isc::Unexpected, "Cannot open output file: "
+                                       << user_chk_output_fname
+                                       << " reason: " << errmsg);
+        }
+    }
+    catch (const std::exception& ex) {
+        // Log the error and return failure.
+        std::cout << "DHCP UserCheckHook could not be loaded: "
+                  << ex.what() << std::endl;
+        ret_val = 1;
+    }
+
+    return (ret_val);
+}
+
+/// @brief Called by the Hooks library manager when the library is unloaded.
+///
+/// Destroys the UserRegistry and closes the outcome file.
+///
+/// @return Always returns 0.
+int unload() {
+    try {
+        user_registry.reset();
+        if (user_chk_output.is_open()) {
+            user_chk_output.close();
+        }
+    } catch (const std::exception& ex) {
+        // On the off chance something goes awry, catch it and log it.
+        // @todo Not sure if we should return a non-zero result or not.
+        std::cout << "DHCP UserCheckHook could not be unloaded: "
+                  << ex.what() << std::endl;
+    }
+
+    return (0);
+}
+
+}

src/hooks/dhcp/user_chk/subnet_select_co.cc

+// Copyright (C) 2013 Internet Systems Consortium, Inc. ("ISC")
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+/// @file Defines the subnet4_select and subnet6_select callout functions.
+
+#include <hooks/hooks.h>
+#include <dhcp/pkt4.h>
+#include <dhcp/dhcp6.h>
+#include <dhcp/pkt6.h>
+#include <dhcpsrv/subnet.h>
+#include <user_registry.h>
+
+#include <fstream>
+#include <string>
+
+using namespace isc::dhcp;
+using namespace isc::hooks;
+using namespace std;
+
+extern UserRegistryPtr user_registry;
+extern std::fstream user_chk_output;
+extern const char* registry_fname;
+extern const char* user_chk_output_fname;
+
+// Functions accessed by the hooks framework use C linkage to avoid the name
+// mangling that accompanies use of the C++ compiler as well as to avoid
+// issues related to namespaces.
+extern "C" {
+
+/// @brief Adds an entry to the end of the user check outcome file.
+///
+/// Each user entry is written in an ini-like format, with one name-value pair
+/// per line as follows:
+///
+/// id_type=<id type>
+/// client=<id str>
+/// subnet=<subnet str>
+/// registered=<is registered>"
+///
+/// where:
+/// <id type> text label of the id type: "HW_ADDR" or "DUID"
+/// <id str> user's id formatted as either isc::dhcp::Hwaddr.toText() or
+/// isc::dhcp::DUID.toText()
+/// <subnet str> selected subnet formatted as isc::dhcp::Subnet4::toText() or
+/// isc::dhcp::Subnet6::toText() as appropriate.
+/// <is registered> "yes" or "no"
+///
+/// Sample IPv4 entry would like this:
+///
+/// @code
+/// id_type=DUID
+/// client=00:01:00:01:19:ef:e6:3b:00:0c:01:02:03:04
+/// subnet=2001:db8:2::/64
+/// registered=yes
+/// id_type=duid
+/// @endcode
+///
+/// Sample IPv4 entry would like this:
+///
+/// @code
+/// id_type=DUID
+/// id_type=HW_ADDR
+/// client=hwtype=1 00:0c:01:02:03:05
+/// subnet=152.77.5.0/24
+/// registered=no
+/// @endcode
+///
+/// @param id_type_str text label identify the id type
+/// @param id_val_str text representation of the user id
+/// @param subnet_str text representation  of the selected subnet
+/// @param registered boolean indicating if the user is registered or not
+void generate_output_record(const std::string& id_type_str,
+                            const std::string& id_val_str,
+                            const std::string& subnet_str,
+                            const bool& registered)
+{
+    user_chk_output << "id_type=" << id_type_str << std::endl
+                    << "client=" << id_val_str << std::endl
+                    << "subnet=" << subnet_str << std::endl
+                    << "registered=" << (registered ? "yes" : "no")
+                    << std::endl;
+
+    // @todo Flush is here to ensure output is immediate for demo purposes.
+    // Performance would generally dictate not using it.
+    flush(user_chk_output);
+}
+
+/// @brief  This callout is called at the "subnet4_select" hook.
+///
+/// This function searches the UserRegistry for the client indicated by the
+/// inbound IPv4 DHCP packet. If the client is found in the registry output
+/// the generate outcome record and return.
+///
+/// If the client is not found in the registry replace the selected subnet
+/// with the restricted access subnet, then generate the outcome record and
+/// return.  By convention, it is assumed that last subnet in the list of
+/// available subnets is the restricted access subnet.
+///
+/// @param handle CalloutHandle which provides access to context.
+///
+/// @return 0 upon success, non-zero otherwise.
+int subnet4_select(CalloutHandle& handle) {
+    if (!user_registry) {
+        std::cout << "DHCP UserCheckHook : subnet4_select UserRegistry is null"
+                  << std::endl;
+        return (1);
+    }
+
+    try {
+        // Get subnet collection. If it's empty just bail nothing to do.
+        const isc::dhcp::Subnet4Collection *subnets = NULL;
+        handle.getArgument("subnet4collection", subnets);
+        if (subnets->size() == 0) {
+            return 0;
+        }
+
+        // Refresh the registry.
+        user_registry->refresh();
+
+        // Get the HWAddress as the user identifier.
+        Pkt4Ptr query;
+        handle.getArgument("query4", query);
+        HWAddrPtr hwaddr = query->getHWAddr();
+
+        // Look for the user.
+        UserPtr registered_user = user_registry->findUser(*hwaddr);
+        if (registered_user) {
+            // User is in the registry, so leave the pre-selected subnet alone.
+            Subnet4Ptr subnet;
+            handle.getArgument("subnet4", subnet);
+            // Add the outcome entry to the output file.
+            generate_output_record(UserId::HW_ADDRESS_STR, hwaddr->toText(),
+                                   subnet->toText(), true);
+        } else {
+            // User is not in the registry, so assign them to the last subnet
+            // in the collection.  By convention we are assuming this is the
+            // restricted subnet.
+            Subnet4Ptr subnet = subnets->back();
+            handle.setArgument("subnet4", subnet);
+            // Add the outcome entry to the output file.
+            generate_output_record(UserId::HW_ADDRESS_STR, hwaddr->toText(),
+                                   subnet->toText(), false);
+        }
+    } catch (const std::exception& ex) {
+        std::cout << "DHCP UserCheckHook : subnet6_select unexpected error: "
+                  << ex.what() << std::endl;
+        return (1);
+    }
+
+    return (0);
+}
+
+/// @brief  This callout is called at the "subnet6_select" hook.
+///
+/// This function searches the UserRegistry for the client indicated by the
+/// inbound IPv6 DHCP packet. If the client is found in the registry generate
+/// the outcome record and return.
+///
+/// If the client is not found in the registry replace the selected subnet
+/// with the restricted access subnet, then generate the outcome record and
+/// return.  By convention, it is assumed that last subnet in the list of
+/// available subnets is the restricted access subnet.
+///
+/// @param handle CalloutHandle which provides access to context.
+///
+/// @return 0 upon success, non-zero otherwise.
+int subnet6_select(CalloutHandle& handle) {
+    if (!user_registry) {
+        std::cout << "DHCP UserCheckHook : subnet6_select UserRegistry is null"
+                  << std::endl;
+        return (1);
+    }
+
+    try {
+        // Get subnet collection. If it's empty just bail nothing to do.
+        const isc::dhcp::Subnet6Collection *subnets = NULL;
+        handle.getArgument("subnet6collection", subnets);
+        if (subnets->size() == 0) {
+            return 0;
+        }
+
+        // Refresh the registry.
+        user_registry->refresh();
+
+        // Get the HWAddress as the user identifier.
+        Pkt6Ptr query;
+        handle.getArgument("query6", query);
+
+        DuidPtr duid;
+        OptionPtr opt_duid = query->getOption(D6O_CLIENTID);
+        if (!opt_duid) {
+            std::cout << "DHCP6 query is missing DUID" << std::endl;
+            return (1);
+        }
+
+        duid = DuidPtr(new DUID(opt_duid->getData()));
+
+        // Look for the user.
+        UserPtr registered_user = user_registry->findUser(*duid);
+        if (registered_user) {
+            // User is in the registry, so leave the pre-selected subnet alone.
+            Subnet6Ptr subnet;
+            handle.getArgument("subnet6", subnet);
+            // Add the outcome entry to the output file.
+            generate_output_record(UserId::DUID_STR, duid->toText(),
+                                   subnet->toText(), true);
+        } else {
+            // User is not in the registry, so assign them to the last subnet
+            // in the collection.  By convention we are assuming this is the
+            // restricted subnet.
+            Subnet6Ptr subnet = subnets->back();
+            handle.setArgument("subnet6", subnet);
+            // Add the outcome entry to the output file.
+            generate_output_record(UserId::DUID_STR, duid->toText(),
+                                   subnet->toText(), false);
+        }
+    } catch (const std::exception& ex) {
+        std::cout << "DHCP UserCheckHook : subnet6_select unexpected error: "
+                  << ex.what() << std::endl;
+        return (1);
+    }
+
+    return (0);
+}
+
+}

src/hooks/dhcp/user_chk/tests/Makefile.am

+SUBDIRS = .
+
+AM_CPPFLAGS = -I$(top_builddir)/src/lib -I$(top_srcdir)/src/lib
+AM_CPPFLAGS += -I$(top_builddir)/src/hooks/dhcp/user_chk
+AM_CPPFLAGS += $(BOOST_INCLUDES) $(BOTAN_INCLUDES)
+AM_CPPFLAGS += -DTEST_DATA_BUILDDIR=\"$(abs_top_builddir)/src/hooks/dhcp/user_chk/tests\"
+AM_CPPFLAGS += -DINSTALL_PROG=\"$(abs_top_srcdir)/install-sh\"
+
+AM_CXXFLAGS = $(B10_CXXFLAGS)
+
+# Some versions of GCC warn about some versions of Boost regarding
+# missing initializer for members in its posix_time.
+# https://svn.boost.org/trac/boost/ticket/3477
+# But older GCC compilers don't have the flag.
+AM_CXXFLAGS += $(WARNING_NO_MISSING_FIELD_INITIALIZERS_CFLAG)
+
+USER_CHK_LIB = $(top_builddir)/src/hooks/dhcp/user_chk/libdhcp_user_chk.la
+
+if USE_STATIC_LINK
+AM_LDFLAGS = -static
+endif
+
+CLEANFILES = *.gcno *.gcda
+
+TESTS_ENVIRONMENT = \
+	$(LIBTOOL) --mode=execute $(VALGRIND_COMMAND)
+
+TESTS =
+if HAVE_GTEST
+TESTS += libdhcp_user_chk_unittests
+
+libdhcp_user_chk_unittests_SOURCES  = 
+libdhcp_user_chk_unittests_SOURCES += ../load_unload.cc
+libdhcp_user_chk_unittests_SOURCES += ../subnet_select_co.cc
+libdhcp_user_chk_unittests_SOURCES += ../version.cc
+libdhcp_user_chk_unittests_SOURCES += ../user.cc ../user.h
+libdhcp_user_chk_unittests_SOURCES += ../user_chk_log.cc ../user_chk_log.h
+# Until logging in dynamically loaded libraries is fixed, exclude these.
+#libdhcp_user_chk_unittests_SOURCES += ../user_chk_messages.cc ../user_chk_messages.h
+libdhcp_user_chk_unittests_SOURCES += ../user_data_source.h
+libdhcp_user_chk_unittests_SOURCES += ../user_file.cc ../user_file.h
+libdhcp_user_chk_unittests_SOURCES += ../user_registry.cc ../user_registry.h
+libdhcp_user_chk_unittests_SOURCES += run_unittests.cc
+libdhcp_user_chk_unittests_SOURCES += userid_unittests.cc
+libdhcp_user_chk_unittests_SOURCES += user_unittests.cc
+libdhcp_user_chk_unittests_SOURCES += user_registry_unittests.cc
+libdhcp_user_chk_unittests_SOURCES += user_file_unittests.cc
+
+libdhcp_user_chk_unittests_CPPFLAGS = $(AM_CPPFLAGS) $(GTEST_INCLUDES) $(LOG4CPLUS_INCLUDES)
+
+libdhcp_user_chk_unittests_LDFLAGS  = $(AM_LDFLAGS)  $(GTEST_LDFLAGS)
+
+libdhcp_user_chk_unittests_CXXFLAGS = $(AM_CXXFLAGS)
+if USE_CLANGPP
+# This is to workaround unused variables tcout and tcerr in
+# log4cplus's streams.h and unused parameters from some of the
+# Boost headers.
+libdhcp_user_chk_unittests_CXXFLAGS += -Wno-unused-parameter
+endif
+
+libdhcp_user_chk_unittests_LDADD = $(top_builddir)/src/lib/log/libb10-log.la
+libdhcp_user_chk_unittests_LDADD += $(top_builddir)/src/lib/util/libb10-util.la
+libdhcp_user_chk_unittests_LDADD += $(top_builddir)/src/lib/hooks/libb10-hooks.la
+libdhcp_user_chk_unittests_LDADD += $(top_builddir)/src/lib/dhcp/libb10-dhcp++.la
+libdhcp_user_chk_unittests_LDADD += $(top_builddir)/src/lib/exceptions/libb10-exceptions.la
+libdhcp_user_chk_unittests_LDADD += $(top_builddir)/src/lib/cc/libb10-cc.la
+libdhcp_user_chk_unittests_LDADD += ${BOTAN_LIBS} ${BOTAN_RPATH}
+libdhcp_user_chk_unittests_LDADD += $(GTEST_LDADD)
+endif
+
+noinst_PROGRAMS = $(TESTS)

src/hooks/dhcp/user_chk/tests/run_unittests.cc

+// Copyright (C) 2013 Internet Systems Consortium, Inc. ("ISC")
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+#include <log/logger_support.h>
+
+#include <gtest/gtest.h>
+
+int
+main(int argc, char* argv[]) {
+    ::testing::InitGoogleTest(&argc, argv);
+    isc::log::initLogger();
+
+    int result = RUN_ALL_TESTS();
+
+    return (result);
+}

src/hooks/dhcp/user_chk/tests/test_data_files_config.h.in

+// Copyright (C) 2013 Internet Systems Consortium, Inc. ("ISC")
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+//
+/// @brief Path to local dir so tests can locate test data files 
+#define USER_CHK_TEST_DIR "@abs_top_srcdir@/src/hooks/dhcp/user_chk/tests"

src/hooks/dhcp/user_chk/tests/test_users_1.txt

+{ "type" : "HW_ADDR", "id" : "01AC00F03344", "opt1" : "true" }
+{ "type" : "DUID", "id" : "225060de0a0b", "opt1" : "true" }

src/hooks/dhcp/user_chk/tests/test_users_err.txt

+{ "type" : "DUID", "id" : "777777777777", "opt1" : "true" }
+{ "type" : "BOGUS", "id" : "01AC00F03344", "opt1" : "true" }

src/hooks/dhcp/user_chk/tests/user_file_unittests.cc

+// Copyright (C) 2013  Internet Systems Consortium, Inc. ("ISC")
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+#include <exceptions/exceptions.h>
+#include <test_data_files_config.h>
+#include <user_file.h>
+
+#include <boost/function.hpp>
+#include <boost/bind.hpp>
+#include <boost/shared_ptr.hpp>
+#include <gtest/gtest.h>
+
+using namespace std;
+
+namespace {
+
+/// @brief Convenience method for reliably building test file path names.
+///
+/// Function prefixes the given file name with a path to unit tests directory
+/// so we can reliably find test data files.
+///
+/// @param name base file name of the test file
+std::string testFilePath(const std::string& name) {
+    return (std::string(USER_CHK_TEST_DIR) + "/" + name);
+}
+
+/// @brief Tests the UserFile constructor.
+TEST(UserFile, construction) {
+    // Verify that a UserFile with no file name is rejected.
+    ASSERT_THROW(UserFile(""), UserFileError);