[network-manager-openswan/dcbw/cleanups: 22/23] test: add test-xfrm.c example code

[Dan Williams <dcbw src gnome org>]

commit 84c849d82257043d76e0e691d84286ecd35a827c
Author: Dan Williams <dcbw redhat com>
Date:   Fri Aug 29 14:45:17 2014 -0500

    test: add test-xfrm.c example code
    
    This is the minimal testcase from which the helper NEVER_DEFAULT
    code was copied.

 .gitignore      |    2 +-
 src/Makefile.am |   12 +++-
 src/show-xfrm.c |  163 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 173 insertions(+), 4 deletions(-)
---
diff --git a/.gitignore b/.gitignore
index ab014de..cd7ad78 100644
--- a/.gitignore
+++ b/.gitignore
@@ -35,4 +35,4 @@ nm-openswan-service.name
 nm-openswan.desktop
 src/nm-openswan-service
 src/nm-openswan-service-helper
-
+src/show-xfrm
diff --git a/src/Makefile.am b/src/Makefile.am
index eb364ea..46f6288 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -18,8 +18,8 @@ AM_CPPFLAGS = \
 libexec_PROGRAMS = nm-openswan-service nm-openswan-service-helper
 
 nm_openswan_service_SOURCES = \
-                               nm-openswan-service.c \
-                               nm-openswan-service.h
+       nm-openswan-service.c \
+       nm-openswan-service.h
 
 nm_openswan_service_LDADD = \
        $(DBUS_LIBS) \
@@ -28,11 +28,17 @@ nm_openswan_service_LDADD = \
        -lutil
 
 nm_openswan_service_helper_SOURCES = \
-                               nm-openswan-service-helper.c
+       nm-openswan-service-helper.c
 
 nm_openswan_service_helper_LDADD = \
        $(DBUS_LIBS) \
        $(NM_LIBS) \
        $(LIBNL_LIBS)
 
+noinst_PROGRAMS = show-xfrm
+
+show_xfrm_SOURCES = show-xfrm.c
+
+show_xfrm_LDADD = $(LIBNL_LIBS) $(GLIB_LIBS)
+
 CLEANFILES = *~
diff --git a/src/show-xfrm.c b/src/show-xfrm.c
new file mode 100644
index 0000000..8c6a5a6
--- /dev/null
+++ b/src/show-xfrm.c
@@ -0,0 +1,163 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: t; c-basic-offset: 4 -*- */
+/* 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Copyright 2014 Red Hat, Inc.
+ */
+
+
+#define _GNU_SOURCE 1
+#include <netlink/netlink.h>
+#include <netlink/msg.h>
+#include <linux/xfrm.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+
+#include <glib.h>
+
+static int
+verify_source (struct nl_msg *msg, gpointer user_data)
+{
+       struct ucred *creds = nlmsg_get_creds (msg);
+
+       if (!creds || creds->pid || creds->uid || creds->gid) {
+               if (creds)
+                       g_warning ("netlink: received non-kernel message (pid %d uid %d gid %d)",
+                                       creds->pid, creds->uid, creds->gid);
+               else
+                       g_warning ("netlink: received message without credentials");
+               return NL_STOP;
+       }
+
+       return NL_OK;
+}
+
+static struct nl_sock *
+setup_socket (void)
+{
+       struct nl_sock *sk;
+       int err;
+
+       sk = nl_socket_alloc ();
+       g_return_val_if_fail (sk, NULL);
+
+       /* Only ever accept messages from kernel */
+       err = nl_socket_modify_cb (sk, NL_CB_MSG_IN, NL_CB_CUSTOM, verify_source, NULL);
+       g_assert (!err);
+
+       err = nl_connect (sk, NETLINK_XFRM);
+       g_assert (!err);
+       err = nl_socket_set_passcred (sk, 1);
+       g_assert (!err);
+
+       return sk;
+}
+
+static void
+xfrm_selector_print (struct xfrm_selector *sel)
+{
+       char buf[INET6_ADDRSTRLEN];
+
+       if (sel->family == AF_INET || sel->family == AF_INET6) {
+               inet_ntop (sel->family, &sel->saddr, buf, sizeof (buf));
+               g_print ("src %s/%u ", buf, sel->prefixlen_s);
+
+               inet_ntop (sel->family, &sel->daddr, buf, sizeof (buf));
+               g_print ("dst %s/%u ", buf, sel->prefixlen_d);
+
+               if (sel->ifindex > 0)
+                       g_print ("ifindex %d ", sel->ifindex);
+               g_print ("\n");
+       }
+}
+
+static int
+parse_reply (struct nl_msg *msg, void *arg)
+{
+       struct nlmsghdr *n = nlmsg_hdr (msg);
+       struct nlattr *tb[XFRMA_MAX + 1];
+       struct xfrm_userpolicy_info *xpinfo = NULL;
+
+       if (n->nlmsg_type != XFRM_MSG_NEWPOLICY) {
+               g_warning ("msg type %d not NEWPOLICY", n->nlmsg_type);
+               return NL_SKIP;
+       }
+
+       /* Netlink message header is followed by 'struct xfrm_userpolicy_info' and
+        * then the attributes.
+        */
+
+       if (!nlmsg_valid_hdr (n, sizeof (struct xfrm_userpolicy_info))) {
+               g_warning ("msg too short");
+               return -NLE_MSG_TOOSHORT;
+       }
+
+       xpinfo = nlmsg_data (n);
+       if (nla_parse (tb, XFRMA_MAX,
+                      nlmsg_attrdata (n, sizeof (struct xfrm_userpolicy_info)),
+                      nlmsg_attrlen (n, sizeof (struct xfrm_userpolicy_info)),
+                      NULL) < 0) {
+               g_warning ("failed to parse attributes");
+               return NL_SKIP;
+       }
+
+       if (tb[XFRMA_TMPL]) {
+               int attrlen = nla_len (tb[XFRMA_TMPL]);
+               struct xfrm_user_tmpl *list = nla_data (tb[XFRMA_TMPL]);
+               int i;
+
+               xfrm_selector_print (&xpinfo->sel);
+
+               for (i = 0; i < attrlen / sizeof (struct xfrm_user_tmpl); i++) {
+                       struct xfrm_user_tmpl *tmpl = &list[i];
+                       char buf[INET6_ADDRSTRLEN];
+
+                       g_print ("    tmpl ");
+
+                       inet_ntop (tmpl->family, (gpointer) &tmpl->saddr, buf, sizeof (buf));
+                       g_print ("src %s ", buf);
+
+                       inet_ntop (tmpl->family, &tmpl->id.daddr, buf, sizeof (buf));
+                       g_print ("dst %s\n", buf);
+               }
+       }
+
+       return NL_OK;
+}
+
+
+int main (int argc, char **argv)
+{
+       struct nl_sock *sk;
+       int err;
+
+       sk = setup_socket ();
+       g_assert (sk);
+
+       err = nl_send_simple (sk, XFRM_MSG_GETPOLICY, NLM_F_DUMP, NULL, 0);
+       if (err < 0) {
+               g_warning ("Error sending: %d %s", err, nl_geterror (err));
+               return 1;
+       }
+
+       nl_socket_modify_cb (sk, NL_CB_VALID, NL_CB_CUSTOM, parse_reply, NULL);
+
+       err = nl_recvmsgs_default (sk);
+       if (err < 0) {
+               g_warning ("Error parsing: %d %s", err, nl_geterror (err));
+               return 1;
+       }
+
+       return 0;
+}