[NetLabel]: core NetLabel subsystem

Add a new kernel subsystem, NetLabel, to provide explicit packet
labeling services (CIPSO, RIPSO, etc.) to LSM developers.  NetLabel is
designed to work in conjunction with a LSM to intercept and decode
security labels on incoming network packets as well as ensure that
outgoing network packets are labeled according to the security
mechanism employed by the LSM.  The NetLabel subsystem is configured
through a Generic NETLINK interface described in the header files
included in this patch.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 158 insertions, 0 deletions

diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c
new file mode 100644
index 000000000000..80022221b0a7
--- /dev/null
+++ b/net/netlabel/netlabel_user.c
@@ -0,0 +1,158 @@
+/*
+ * NetLabel NETLINK Interface
+ *
+ * This file defines the NETLINK interface for the NetLabel system.  The
+ * NetLabel system manages static and dynamic label mappings for network
+ * protocols such as CIPSO and RIPSO.
+ *
+ * Author: Paul Moore <paul.moore@hp.com>
+ *
+ */
+
+/*
+ * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/socket.h>
+#include <net/sock.h>
+#include <net/netlink.h>
+#include <net/genetlink.h>
+#include <net/netlabel.h>
+#include <asm/bug.h>
+
+#include "netlabel_mgmt.h"
+#include "netlabel_unlabeled.h"
+#include "netlabel_cipso_v4.h"
+#include "netlabel_user.h"
+
+/*
+ * NetLabel NETLINK Setup Functions
+ */
+
+/**
+ * netlbl_netlink_init - Initialize the NETLINK communication channel
+ *
+ * Description:
+ * Call out to the NetLabel components so they can register their families and
+ * commands with the Generic NETLINK mechanism.  Returns zero on success and
+ * non-zero on failure.
+ *
+ */
+int netlbl_netlink_init(void)
+{
+	int ret_val;
+
+	ret_val = netlbl_mgmt_genl_init();
+	if (ret_val != 0)
+		return ret_val;
+
+	ret_val = netlbl_cipsov4_genl_init();
+	if (ret_val != 0)
+		return ret_val;
+
+	ret_val = netlbl_unlabel_genl_init();
+	if (ret_val != 0)
+		return ret_val;
+
+	return 0;
+}
+
+/*
+ * NetLabel Common Protocol Functions
+ */
+
+/**
+ * netlbl_netlink_send_ack - Send an ACK message
+ * @info: the generic NETLINK information
+ * @genl_family: the generic NETLINK family ID value
+ * @ack_cmd: the generic NETLINK family ACK command value
+ * @ret_code: return code to use
+ *
+ * Description:
+ * This function sends an ACK message to the sender of the NETLINK message
+ * specified by @info.
+ *
+ */
+void netlbl_netlink_send_ack(const struct genl_info *info,
+			     u32 genl_family,
+			     u8 ack_cmd,
+			     u32 ret_code)
+{
+	size_t data_size;
+	struct sk_buff *skb;
+
+	data_size = GENL_HDRLEN + 2 * NETLBL_LEN_U32;
+	skb = netlbl_netlink_alloc_skb(0, data_size, GFP_KERNEL);
+	if (skb == NULL)
+		return;
+
+	if (netlbl_netlink_hdr_put(skb,
+				   info->snd_pid,
+				   0,
+				   genl_family,
+				   ack_cmd) == NULL)
+		goto send_ack_failure;
+
+	if (nla_put_u32(skb, NLA_U32, info->snd_seq) != 0)
+		goto send_ack_failure;
+	if (nla_put_u32(skb, NLA_U32, ret_code) != 0)
+		goto send_ack_failure;
+
+	netlbl_netlink_snd(skb, info->snd_pid);
+	return;
+
+send_ack_failure:
+	kfree_skb(skb);
+}
+
+/*
+ * NETLINK I/O Functions
+ */
+
+/**
+ * netlbl_netlink_snd - Send a NetLabel message
+ * @skb: NetLabel message
+ * @pid: destination PID
+ *
+ * Description:
+ * Sends a unicast NetLabel message over the NETLINK socket.
+ *
+ */
+int netlbl_netlink_snd(struct sk_buff *skb, u32 pid)
+{
+	return genlmsg_unicast(skb, pid);
+}
+
+/**
+ * netlbl_netlink_snd - Send a NetLabel message
+ * @skb: NetLabel message
+ * @pid: sending PID
+ * @group: multicast group id
+ *
+ * Description:
+ * Sends a multicast NetLabel message over the NETLINK socket to all members
+ * of @group except @pid.
+ *
+ */
+int netlbl_netlink_snd_multicast(struct sk_buff *skb, u32 pid, u32 group)
+{
+	return genlmsg_multicast(skb, pid, group);
+}