qca-nss-ecm/ecm_db/ecm_db.c - manifest_repos/sdk - Git at Google

 /*
  **************************************************************************
  * Copyright (c) 2014-2021, The Linux Foundation. All rights reserved.
  * 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 THE AUTHOR DISCLAIMS ALL WARRANTIES
  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR 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 <linux/version.h>
 #include <linux/types.h>
 #include <linux/ip.h>
 #include <linux/tcp.h>
 #include <linux/module.h>
 #include <linux/skbuff.h>
 #include <linux/icmp.h>
 #include <linux/kthread.h>
 #include <linux/debugfs.h>
 #include <linux/pkt_sched.h>
 #include <linux/string.h>
 #include <linux/random.h>
 #include <net/route.h>
 #include <net/ip.h>
 #include <net/tcp.h>
 #include <asm/unaligned.h>
 #include <asm/uaccess.h>	/* for put_user */
 #include <net/ipv6.h>
 #include <net/ip6_route.h>
 #include <linux/inet.h>
 #include <linux/in.h>
 #include <linux/udp.h>
 #include <linux/tcp.h>
 #include <linux/netfilter_ipv4.h>
 #include <linux/netfilter_bridge.h>
 #include <net/netfilter/nf_conntrack.h>
 #include <net/netfilter/nf_conntrack_helper.h>
 #include <net/netfilter/nf_conntrack_l4proto.h>
 #include <net/netfilter/nf_conntrack_core.h>
 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
 #include <net/netfilter/ipv4/nf_defrag_ipv4.h>

 /*
  * Debug output levels
  * 0 = OFF
  * 1 = ASSERTS / ERRORS
  * 2 = 1 + WARN
  * 3 = 2 + INFO
  * 4 = 3 + TRACE
  */
 #define DEBUG_LEVEL ECM_DB_DEBUG_LEVEL

 #include "ecm_types.h"
 #include "ecm_db_types.h"
 #include "ecm_state.h"
 #include "ecm_tracker.h"
 #include "ecm_classifier.h"
 #include "ecm_front_end_types.h"
 #include "ecm_classifier_default.h"
 #include "ecm_db.h"
 #include "ecm_front_end_ipv4.h"
 #ifdef ECM_IPV6_ENABLE
 #include "ecm_front_end_ipv6.h"
 #endif
 #include "ecm_notifier_pvt.h"
 #include "ecm_interface.h"

 /*
  * Locking of the database - concurrency control
  */
 DEFINE_SPINLOCK(ecm_db_lock);					/* Protect the table from SMP access. */

 /*
  * Debugfs dentry object.
  */
 static struct dentry *ecm_db_dentry;

 /*
  * Management thread control
  */
 bool ecm_db_terminate_pending = false;			/* When true the user has requested termination */

 /*
  * Random seed used during hash calculations
  */
 uint32_t ecm_db_jhash_rnd __read_mostly;

 /*
  * ecm_db_obj_dir_strings[]
  *      Common array that maps the object direction to a string
  */
 char *ecm_db_obj_dir_strings[ECM_DB_OBJ_DIR_MAX] = {
         "FROM",
         "TO",
         "FROM_NAT",
         "TO_NAT"
 };

 /*
  * Global listener instance for DB events.
  */
 static struct ecm_db_listener_instance *ecm_db_li;

 /*
  * ecm_db_adv_stats_state_write()
  *	Write out advanced stats state
  */
 int ecm_db_adv_stats_state_write(struct ecm_state_file_instance *sfi,uint64_t from_data_total, uint64_t to_data_total,
 				uint64_t from_packet_total, uint64_t to_packet_total, uint64_t from_data_total_dropped,
 				uint64_t to_data_total_dropped, uint64_t from_packet_total_dropped, uint64_t to_packet_total_dropped)
 {
 	int result;

 	if ((result = ecm_state_prefix_add(sfi, "adv_stats"))) {
 		return result;
 	}

 	if ((result = ecm_state_write(sfi, "from_data_total", "%llu", from_data_total))) {
 		return result;
 	}
 	if ((result = ecm_state_write(sfi, "to_data_total", "%llu", to_data_total))) {
 		return result;
 	}
 	if ((result = ecm_state_write(sfi, "from_packet_total", "%llu", from_packet_total))) {
 		return result;
 	}
 	if ((result = ecm_state_write(sfi, "to_packet_total", "%llu", to_packet_total))) {
 		return result;
 	}
 	if ((result = ecm_state_write(sfi, "from_data_total_dropped", "%llu", from_data_total_dropped))) {
 		return result;
 	}
 	if ((result = ecm_state_write(sfi, "to_data_total_dropped", "%llu", to_data_total_dropped))) {
 		return result;
 	}
 	if ((result = ecm_state_write(sfi, "from_packet_total_dropped", "%llu", from_packet_total_dropped))) {
 		return result;
 	}
 	if ((result = ecm_state_write(sfi, "to_packet_total_dropped", "%llu", to_packet_total_dropped))) {
 		return result;
 	}

 	return ecm_state_prefix_remove(sfi);
 }

 /*
  * ecm_db_get_defunct_all()
  *	Reading this file returns the accumulated total of all objects
  */
 static ssize_t ecm_db_get_defunct_all(struct file *file,
 					char __user *user_buf,
 					size_t sz, loff_t *ppos)
 {
 	int ret;
 	int num;
 	char *buf;

 	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!buf) {
 		return -ENOMEM;
 	}

 	/*
 	 * Operate under our locks
 	 */
 	spin_lock_bh(&ecm_db_lock);
 	num = _ecm_db_connection_count_get() + _ecm_db_mapping_count_get() + _ecm_db_host_count_get()
 			+ _ecm_db_node_count_get() + _ecm_db_iface_count_get();
 	spin_unlock_bh(&ecm_db_lock);

 	ret = snprintf(buf, (ssize_t)PAGE_SIZE, "%d\n", num);
 	if (ret < 0) {
 		kfree(buf);
 		return ret;
 	}

 	ret = simple_read_from_buffer(user_buf, sz, ppos, buf, ret);
 	kfree(buf);
 	return ret;
 }

 /*
  * ecm_db_set_defunct_all()
  */
 static ssize_t ecm_db_set_defunct_all(struct file *file,
 					const char __user *user_buf,
 					size_t sz, loff_t *ppos)
 {
 	ecm_db_connection_defunct_all();
 	return sz;
 }

 /*
  * File operations for defunct_all.
  */
 static struct file_operations ecm_db_defunct_all_fops = {
 	.read = ecm_db_get_defunct_all,
 	.write = ecm_db_set_defunct_all,
 };

 /*
  * ecm_db_ipv4_route_table_update_event()
  *	This is a call back for "routing table update event for IPv4".
  */
 static int ecm_db_ipv4_route_table_update_event(struct notifier_block *nb,
 					       unsigned long event,
 					       void *ptr)
 {
 	DEBUG_TRACE("route table update event v4\n");

 	/*
 	 * Disable IPv4 frontend processing until defunct function call is completed.
 	 */
 	ecm_front_end_ipv4_stop(1);

 	ecm_db_connection_defunct_ip_version(4);

 	/*
 	 * Re-enable IPv4 frontend processing.
 	 */
 	ecm_front_end_ipv4_stop(0);

 	return NOTIFY_DONE;
 }

 static struct notifier_block ecm_db_iproute_table_update_nb = {
 	.notifier_call = ecm_db_ipv4_route_table_update_event,
 };

 #ifdef ECM_IPV6_ENABLE
 /*
  * ecm_db_ipv6_route_table_update_event()
  *	This is a call back for "routing table update event for IPv6".
  */
 static int ecm_db_ipv6_route_table_update_event(struct notifier_block *nb,
 					       unsigned long event,
 					       void *ptr)
 {
 	struct fib6_config *cfg = (struct fib6_config *)ptr;
 	struct ecm_db_connection_instance *ci;

 	DEBUG_TRACE("route table update event v6\n");

 	if ((event != RTM_DELROUTE) && (event != RTM_NEWROUTE)) {
 		DEBUG_WARN("%px: Unhandled route table event: %lu\n", cfg, event);
 		return NOTIFY_DONE;
 	}

 	/*
 	 * If a default route is changed, fc_dst address is set to all zeros.
 	 * In this case, we should defunct all the IPv6 flows.
 	 */
 	if (ipv6_addr_any(&cfg->fc_dst)) {
 		DEBUG_TRACE("%px fc_dst (%pI6), default route is changed, defunct all IPv6 connections\n",
 			    cfg, &cfg->fc_dst);
 		ecm_db_connection_defunct_ip_version(6);
 		return NOTIFY_DONE;
 	}

 	/*
 	 * Disable IPv6 frontend processing until defunct function call is completed.
 	 */
 	ecm_front_end_ipv6_stop(1);

 	/*
 	 * Iterate all connections
 	 */
 	ci = ecm_db_connections_get_and_ref_first();
 	while (ci) {
 		struct ecm_db_connection_instance *cin;
 		struct in6_addr prefix_addr;
 		struct in6_addr ecm_in6 = IN6ADDR_ANY_INIT;
 		ip_addr_t ecm_addr;
 		struct ecm_db_iface_instance *interfaces[ECM_DB_IFACE_HEIRARCHY_MAX];
 		int32_t if_first;
 		struct net_device *ecm_dev;
 		struct net_device *fc_dev;
 		bool is_dest_ip_match = true;
 		ecm_db_obj_dir_t obj_dir = ECM_DB_OBJ_DIR_TO;

 		if (ci->ip_version != 6) {
 			goto next;
 		}

 		/*
 		 * Get the ECM connection's destination IPv6 address.
 		 */
 		ecm_db_connection_address_get(ci, ECM_DB_OBJ_DIR_TO, ecm_addr);
 		ECM_IP_ADDR_TO_NIN6_ADDR(ecm_in6, ecm_addr);

 		/*
 		 * Compute ECM connection's prefix destination address by masking it with the
 		 * route config's destination address prefix length.
 		 */
 		ipv6_addr_prefix(&prefix_addr, &ecm_in6, cfg->fc_dst_len);

 		DEBUG_TRACE("dest addr prefix: %pI6 prefix_len: %d ecm_in6: %pI6\n", &prefix_addr, cfg->fc_dst_len, &ecm_in6);

 		/*
 		 * Compare the ECM connection's destination address prefix with the route config's
 		 * destination address. If they are not equal, try with the ECM's source address prefix.
 		 * Because ECM can create the connection in the reply direction, and in this case, ECM
 		 * connection's source prefix IP address will match with the route config's dst IP address.
 		 *
 		 * If none of them match with the route config's destination address, this means that
 		 * this connection is not related to this route change event.
 		 * We should check with the next connection.
 		 */
 		if (ipv6_addr_cmp(&prefix_addr, &cfg->fc_dst)) {
 			DEBUG_TRACE("dest addr prefix: %pI6 not equal to cfg->fc_dst: %pI6, go to next connection\n", &prefix_addr, &cfg->fc_dst);

 			/*
 			 * ECM's destination address didn't match.
 			 * Get the ECM connection's source IPv6 address.
 			 */
 			ecm_db_connection_address_get(ci, ECM_DB_OBJ_DIR_FROM, ecm_addr);
 			ECM_IP_ADDR_TO_NIN6_ADDR(ecm_in6, ecm_addr);

 			/*
 			 * Compute ECM connection's prefix source address by masking it with the
 			 * route config's destination address prefix length.
 			 */
 			ipv6_addr_prefix(&prefix_addr, &ecm_in6, cfg->fc_dst_len);

 			DEBUG_TRACE("src addr prefix: %pI6 prefix_len: %d ecm_in6: %pI6\n", &prefix_addr, cfg->fc_dst_len, &ecm_in6);

 			if (ipv6_addr_cmp(&prefix_addr, &cfg->fc_dst)) {
 				DEBUG_TRACE("src addr prefix: %pI6 not equal to cfg->fc_dst: %pI6, go to next connection\n", &prefix_addr, &cfg->fc_dst);
 				goto next;
 			}

 			is_dest_ip_match = false;
 			obj_dir = ECM_DB_OBJ_DIR_FROM;
 		}

 		DEBUG_TRACE("%px: ECM connection's %s address prefix: %pI6 equals to cfg->fc_dst: %pI6\n",
 			    ci, is_dest_ip_match?"dest":"src", &prefix_addr, &cfg->fc_dst);

 		/*
 		 * If the event is a route delete event, comparing only the IP address is enough
 		 * to defunct the connection.
 		 */
 		if (event == RTM_DELROUTE) {
 			DEBUG_TRACE("%px: Route DELETE event, defunct the connection\n", ci);
 			ecm_db_connection_make_defunct(ci);
 			goto next;
 		}

 		DEBUG_TRACE("%px: Route ADD event\n", ci);

 		/*
 		 * If there is a route for this connection's source or destination IP address, we should
 		 * compare the devices as well, because the IP address could remain the same, but
 		 * the output device could be changed. So, the flows should take the new out device
 		 * for their route.
 		 */
 		if_first = ecm_db_connection_interfaces_get_and_ref(ci, interfaces, obj_dir);
 		if (if_first == ECM_DB_IFACE_HEIRARCHY_MAX) {
 			DEBUG_WARN("%px: Failed to get %s interfaces list\n",
 					ci, ecm_db_obj_dir_strings[obj_dir]);
 			goto next;
 		}

 		/*
 		 * Inner most interface has the IP address, so we should get that interface.
 		 */
 		ecm_dev = dev_get_by_index(&init_net,
 				  ecm_db_iface_interface_identifier_get(interfaces[ECM_DB_IFACE_HEIRARCHY_MAX - 1]));
 		if (!ecm_dev) {
 			DEBUG_WARN("%px: unable to find ecm netdevice\n", ci);
 			ecm_db_connection_interfaces_deref(interfaces, if_first);
 			goto next;
 		}
 		ecm_db_connection_interfaces_deref(interfaces, if_first);

 		fc_dev = dev_get_by_index(&init_net, cfg->fc_ifindex);
 		if (!fc_dev) {
 			DEBUG_WARN("%px: unable to find fib6_config netdevice\n", ci);
 			dev_put(ecm_dev);
 			goto next;
 		}

 		/*
 		 * Compare the ECM connection's netdevice with the route change config's netdevice.
 		 * If they are different, this means the new route effected the connection. So, defunct it.
 		 */
 		if (ecm_dev != fc_dev) {
 			DEBUG_TRACE("%px: fib6_config dev: %s is different from ecm dev: %s, defunct the connection\n",
 				    ci, fc_dev->name, ecm_dev->name);
 			ecm_db_connection_make_defunct(ci);
 		}
 		dev_put(fc_dev);
 		dev_put(ecm_dev);
 next:
 		cin = ecm_db_connection_get_and_ref_next(ci);
 		ecm_db_connection_deref(ci);
 		ci = cin;
 	}

 	/*
 	 * Re-enable IPv6 frontend processing.
 	 */
 	ecm_front_end_ipv6_stop(0);
 	return NOTIFY_DONE;
 }

 static struct notifier_block ecm_db_ip6route_table_update_nb = {
 	.notifier_call = ecm_db_ipv6_route_table_update_event,
 };
 #endif

 /*
  * ecm_db_init()
  */
 int ecm_db_init(struct dentry *dentry)
 {
 	DEBUG_INFO("ECM Module init\n");

 	ecm_db_dentry = debugfs_create_dir("ecm_db", dentry);
 	if (!ecm_db_dentry) {
 		DEBUG_ERROR("Failed to create ecm db directory in debugfs\n");
 		return -1;
 	}

 	/*
 	 * Get a random seed for jhash()
 	 */
 	get_random_bytes(&ecm_db_jhash_rnd, sizeof(ecm_db_jhash_rnd));
 	printk(KERN_INFO "ECM database jhash random seed: 0x%x\n", ecm_db_jhash_rnd);

 	if (!ecm_db_connection_init(ecm_db_dentry)) {
 		goto init_cleanup;
 	}

 	if (!ecm_db_host_init(ecm_db_dentry)) {
 		goto init_cleanup_1;
 	}

 	if (!ecm_db_mapping_init(ecm_db_dentry)) {
 		goto init_cleanup_2;
 	}

 	if (!ecm_db_node_init(ecm_db_dentry)) {
 		goto init_cleanup_3;
 	}

 	if (!ecm_db_iface_init(ecm_db_dentry)) {
 		goto init_cleanup_4;
 	}

 	if (!debugfs_create_file("defunct_all", S_IRUGO | S_IWUSR, ecm_db_dentry,
 					NULL, &ecm_db_defunct_all_fops)) {
 		DEBUG_ERROR("Failed to create ecm db defunct_all file in debugfs\n");
 		goto init_cleanup_4;
 	}

 	ecm_db_li = ecm_db_listener_alloc();
 	if (!ecm_db_li) {
 		DEBUG_ERROR("%px: Failed to allocate a listener instance\n", dentry);
 		goto init_cleanup_4;
 	}
 	ecm_db_listener_add(ecm_db_li,
 			NULL, /* ecm_notifier_iface_added */
 			NULL, /* ecm_notifier_iface_removed */
 			NULL, /* ecm_notifier_node_added */
 			NULL, /* ecm_notifier_node_removed */
 			NULL, /* ecm_notifier_host_added */
 			NULL, /* ecm_notifier_host_removed */
 			NULL, /* ecm_notifier_mapping_added */
 			NULL, /* ecm_notifier_mapping_removed */
 			ecm_notifier_connection_added,
 			ecm_notifier_connection_removed,
 			NULL, /* ecm_notifier_connection_final */
 			NULL);

 	/*
 	 * Initialize the timer resources.
 	 */
 	ecm_db_timer_init();

 	/*
 	 * register for route table modification events
 	 */
 	ip_rt_register_notifier(&ecm_db_iproute_table_update_nb);
 #ifdef ECM_IPV6_ENABLE
 	rt6_register_notifier(&ecm_db_ip6route_table_update_nb);
 #endif
 	return 0;

 init_cleanup_4:
 	ecm_db_node_exit();
 init_cleanup_3:
 	ecm_db_mapping_exit();
 init_cleanup_2:
 	ecm_db_host_exit();
 init_cleanup_1:
 	ecm_db_connection_exit();
 init_cleanup:
 	debugfs_remove_recursive(ecm_db_dentry);
 	return -1;
 }
 EXPORT_SYMBOL(ecm_db_init);

 /*
  * ecm_db_exit()
  */
 void ecm_db_exit(void)
 {
 	DEBUG_INFO("ECM DB Module exit\n");

 	spin_lock_bh(&ecm_db_lock);
 	ecm_db_terminate_pending = true;
 	spin_unlock_bh(&ecm_db_lock);

 	/*
 	 * unregister for route table update events
 	 */
 	ip_rt_unregister_notifier(&ecm_db_iproute_table_update_nb);
 #ifdef ECM_IPV6_ENABLE
 	rt6_unregister_notifier(&ecm_db_ip6route_table_update_nb);
 #endif
 	ecm_db_connection_defunct_all();

 	/*
 	 * Clean-up the timer resources.
 	 */
 	ecm_db_timer_exit();

 	if (ecm_db_li) {
 		ecm_db_listener_deref(ecm_db_li);
 		ecm_db_li = NULL;
 	}

 	/*
 	 * Free the database.
 	 */
 	ecm_db_node_exit();
 	ecm_db_mapping_exit();
 	ecm_db_host_exit();
 	ecm_db_connection_exit();

 	/*
 	 * Remove the debugfs files recursively.
 	 */
 	if (ecm_db_dentry) {
 		debugfs_remove_recursive(ecm_db_dentry);
 	}
 }
 EXPORT_SYMBOL(ecm_db_exit);
	/*
	**************************************************************************
	* Copyright (c) 2014-2021, The Linux Foundation. All rights reserved.
	* 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 THE AUTHOR DISCLAIMS ALL WARRANTIES
	* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
	* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR 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 <linux/version.h>
	#include <linux/types.h>
	#include <linux/ip.h>
	#include <linux/tcp.h>
	#include <linux/module.h>
	#include <linux/skbuff.h>
	#include <linux/icmp.h>
	#include <linux/kthread.h>
	#include <linux/debugfs.h>
	#include <linux/pkt_sched.h>
	#include <linux/string.h>
	#include <linux/random.h>
	#include <net/route.h>
	#include <net/ip.h>
	#include <net/tcp.h>
	#include <asm/unaligned.h>
	#include <asm/uaccess.h> /* for put_user */
	#include <net/ipv6.h>
	#include <net/ip6_route.h>
	#include <linux/inet.h>
	#include <linux/in.h>
	#include <linux/udp.h>
	#include <linux/tcp.h>
	#include <linux/netfilter_ipv4.h>
	#include <linux/netfilter_bridge.h>
	#include <net/netfilter/nf_conntrack.h>
	#include <net/netfilter/nf_conntrack_helper.h>
	#include <net/netfilter/nf_conntrack_l4proto.h>
	#include <net/netfilter/nf_conntrack_core.h>
	#include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
	#include <net/netfilter/ipv4/nf_defrag_ipv4.h>

	/*
	* Debug output levels
	* 0 = OFF
	* 1 = ASSERTS / ERRORS
	* 2 = 1 + WARN
	* 3 = 2 + INFO
	* 4 = 3 + TRACE
	*/
	#define DEBUG_LEVEL ECM_DB_DEBUG_LEVEL

	#include "ecm_types.h"
	#include "ecm_db_types.h"
	#include "ecm_state.h"
	#include "ecm_tracker.h"
	#include "ecm_classifier.h"
	#include "ecm_front_end_types.h"
	#include "ecm_classifier_default.h"
	#include "ecm_db.h"
	#include "ecm_front_end_ipv4.h"
	#ifdef ECM_IPV6_ENABLE
	#include "ecm_front_end_ipv6.h"
	#endif
	#include "ecm_notifier_pvt.h"
	#include "ecm_interface.h"

	/*
	* Locking of the database - concurrency control
	*/
	DEFINE_SPINLOCK(ecm_db_lock); /* Protect the table from SMP access. */

	/*
	* Debugfs dentry object.
	*/
	static struct dentry *ecm_db_dentry;

	/*
	* Management thread control
	*/
	bool ecm_db_terminate_pending = false; /* When true the user has requested termination */

	/*
	* Random seed used during hash calculations
	*/
	uint32_t ecm_db_jhash_rnd __read_mostly;

	/*
	* ecm_db_obj_dir_strings[]
	* Common array that maps the object direction to a string
	*/
	char *ecm_db_obj_dir_strings[ECM_DB_OBJ_DIR_MAX] = {
	"FROM",
	"TO",
	"FROM_NAT",
	"TO_NAT"
	};

	/*
	* Global listener instance for DB events.
	*/
	static struct ecm_db_listener_instance *ecm_db_li;

	/*
	* ecm_db_adv_stats_state_write()
	* Write out advanced stats state
	*/
	int ecm_db_adv_stats_state_write(struct ecm_state_file_instance *sfi,uint64_t from_data_total, uint64_t to_data_total,
	uint64_t from_packet_total, uint64_t to_packet_total, uint64_t from_data_total_dropped,
	uint64_t to_data_total_dropped, uint64_t from_packet_total_dropped, uint64_t to_packet_total_dropped)
	{
	int result;

	if ((result = ecm_state_prefix_add(sfi, "adv_stats"))) {
	return result;
	}

	if ((result = ecm_state_write(sfi, "from_data_total", "%llu", from_data_total))) {
	return result;
	}
	if ((result = ecm_state_write(sfi, "to_data_total", "%llu", to_data_total))) {
	return result;
	}
	if ((result = ecm_state_write(sfi, "from_packet_total", "%llu", from_packet_total))) {
	return result;
	}
	if ((result = ecm_state_write(sfi, "to_packet_total", "%llu", to_packet_total))) {
	return result;
	}
	if ((result = ecm_state_write(sfi, "from_data_total_dropped", "%llu", from_data_total_dropped))) {
	return result;
	}
	if ((result = ecm_state_write(sfi, "to_data_total_dropped", "%llu", to_data_total_dropped))) {
	return result;
	}
	if ((result = ecm_state_write(sfi, "from_packet_total_dropped", "%llu", from_packet_total_dropped))) {
	return result;
	}
	if ((result = ecm_state_write(sfi, "to_packet_total_dropped", "%llu", to_packet_total_dropped))) {
	return result;
	}

	return ecm_state_prefix_remove(sfi);
	}

	/*
	* ecm_db_get_defunct_all()
	* Reading this file returns the accumulated total of all objects
	*/
	static ssize_t ecm_db_get_defunct_all(struct file *file,
	char __user *user_buf,
	size_t sz, loff_t *ppos)
	{
	int ret;
	int num;
	char *buf;

	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
	if (!buf) {
	return -ENOMEM;
	}

	/*
	* Operate under our locks
	*/
	spin_lock_bh(&ecm_db_lock);
	num = _ecm_db_connection_count_get() + _ecm_db_mapping_count_get() + _ecm_db_host_count_get()
	+ _ecm_db_node_count_get() + _ecm_db_iface_count_get();
	spin_unlock_bh(&ecm_db_lock);

	ret = snprintf(buf, (ssize_t)PAGE_SIZE, "%d\n", num);
	if (ret < 0) {
	kfree(buf);
	return ret;
	}

	ret = simple_read_from_buffer(user_buf, sz, ppos, buf, ret);
	kfree(buf);
	return ret;
	}

	/*
	* ecm_db_set_defunct_all()
	*/
	static ssize_t ecm_db_set_defunct_all(struct file *file,
	const char __user *user_buf,
	size_t sz, loff_t *ppos)
	{
	ecm_db_connection_defunct_all();
	return sz;
	}

	/*
	* File operations for defunct_all.
	*/
	static struct file_operations ecm_db_defunct_all_fops = {
	.read = ecm_db_get_defunct_all,
	.write = ecm_db_set_defunct_all,
	};

	/*
	* ecm_db_ipv4_route_table_update_event()
	* This is a call back for "routing table update event for IPv4".
	*/
	static int ecm_db_ipv4_route_table_update_event(struct notifier_block *nb,
	unsigned long event,
	void *ptr)
	{
	DEBUG_TRACE("route table update event v4\n");

	/*
	* Disable IPv4 frontend processing until defunct function call is completed.
	*/
	ecm_front_end_ipv4_stop(1);

	ecm_db_connection_defunct_ip_version(4);

	/*
	* Re-enable IPv4 frontend processing.
	*/
	ecm_front_end_ipv4_stop(0);

	return NOTIFY_DONE;
	}

	static struct notifier_block ecm_db_iproute_table_update_nb = {
	.notifier_call = ecm_db_ipv4_route_table_update_event,
	};

	#ifdef ECM_IPV6_ENABLE
	/*
	* ecm_db_ipv6_route_table_update_event()
	* This is a call back for "routing table update event for IPv6".
	*/
	static int ecm_db_ipv6_route_table_update_event(struct notifier_block *nb,
	unsigned long event,
	void *ptr)
	{
	struct fib6_config cfg = (struct fib6_config )ptr;
	struct ecm_db_connection_instance *ci;

	DEBUG_TRACE("route table update event v6\n");

	if ((event != RTM_DELROUTE) && (event != RTM_NEWROUTE)) {
	DEBUG_WARN("%px: Unhandled route table event: %lu\n", cfg, event);
	return NOTIFY_DONE;
	}

	/*
	* If a default route is changed, fc_dst address is set to all zeros.
	* In this case, we should defunct all the IPv6 flows.
	*/
	if (ipv6_addr_any(&cfg->fc_dst)) {
	DEBUG_TRACE("%px fc_dst (%pI6), default route is changed, defunct all IPv6 connections\n",
	cfg, &cfg->fc_dst);
	ecm_db_connection_defunct_ip_version(6);
	return NOTIFY_DONE;
	}

	/*
	* Disable IPv6 frontend processing until defunct function call is completed.
	*/
	ecm_front_end_ipv6_stop(1);

	/*
	* Iterate all connections
	*/
	ci = ecm_db_connections_get_and_ref_first();
	while (ci) {
	struct ecm_db_connection_instance *cin;
	struct in6_addr prefix_addr;
	struct in6_addr ecm_in6 = IN6ADDR_ANY_INIT;
	ip_addr_t ecm_addr;
	struct ecm_db_iface_instance *interfaces[ECM_DB_IFACE_HEIRARCHY_MAX];
	int32_t if_first;
	struct net_device *ecm_dev;
	struct net_device *fc_dev;
	bool is_dest_ip_match = true;
	ecm_db_obj_dir_t obj_dir = ECM_DB_OBJ_DIR_TO;

	if (ci->ip_version != 6) {
	goto next;
	}

	/*
	* Get the ECM connection's destination IPv6 address.
	*/
	ecm_db_connection_address_get(ci, ECM_DB_OBJ_DIR_TO, ecm_addr);
	ECM_IP_ADDR_TO_NIN6_ADDR(ecm_in6, ecm_addr);

	/*
	* Compute ECM connection's prefix destination address by masking it with the
	* route config's destination address prefix length.
	*/
	ipv6_addr_prefix(&prefix_addr, &ecm_in6, cfg->fc_dst_len);

	DEBUG_TRACE("dest addr prefix: %pI6 prefix_len: %d ecm_in6: %pI6\n", &prefix_addr, cfg->fc_dst_len, &ecm_in6);

	/*
	* Compare the ECM connection's destination address prefix with the route config's
	* destination address. If they are not equal, try with the ECM's source address prefix.
	* Because ECM can create the connection in the reply direction, and in this case, ECM
	* connection's source prefix IP address will match with the route config's dst IP address.
	*
	* If none of them match with the route config's destination address, this means that
	* this connection is not related to this route change event.
	* We should check with the next connection.
	*/
	if (ipv6_addr_cmp(&prefix_addr, &cfg->fc_dst)) {
	DEBUG_TRACE("dest addr prefix: %pI6 not equal to cfg->fc_dst: %pI6, go to next connection\n", &prefix_addr, &cfg->fc_dst);

	/*
	* ECM's destination address didn't match.
	* Get the ECM connection's source IPv6 address.
	*/
	ecm_db_connection_address_get(ci, ECM_DB_OBJ_DIR_FROM, ecm_addr);
	ECM_IP_ADDR_TO_NIN6_ADDR(ecm_in6, ecm_addr);

	/*
	* Compute ECM connection's prefix source address by masking it with the
	* route config's destination address prefix length.
	*/
	ipv6_addr_prefix(&prefix_addr, &ecm_in6, cfg->fc_dst_len);

	DEBUG_TRACE("src addr prefix: %pI6 prefix_len: %d ecm_in6: %pI6\n", &prefix_addr, cfg->fc_dst_len, &ecm_in6);

	if (ipv6_addr_cmp(&prefix_addr, &cfg->fc_dst)) {
	DEBUG_TRACE("src addr prefix: %pI6 not equal to cfg->fc_dst: %pI6, go to next connection\n", &prefix_addr, &cfg->fc_dst);
	goto next;
	}

	is_dest_ip_match = false;
	obj_dir = ECM_DB_OBJ_DIR_FROM;
	}

	DEBUG_TRACE("%px: ECM connection's %s address prefix: %pI6 equals to cfg->fc_dst: %pI6\n",
	ci, is_dest_ip_match?"dest":"src", &prefix_addr, &cfg->fc_dst);

	/*
	* If the event is a route delete event, comparing only the IP address is enough
	* to defunct the connection.
	*/
	if (event == RTM_DELROUTE) {
	DEBUG_TRACE("%px: Route DELETE event, defunct the connection\n", ci);
	ecm_db_connection_make_defunct(ci);
	goto next;
	}

	DEBUG_TRACE("%px: Route ADD event\n", ci);

	/*
	* If there is a route for this connection's source or destination IP address, we should
	* compare the devices as well, because the IP address could remain the same, but
	* the output device could be changed. So, the flows should take the new out device
	* for their route.
	*/
	if_first = ecm_db_connection_interfaces_get_and_ref(ci, interfaces, obj_dir);
	if (if_first == ECM_DB_IFACE_HEIRARCHY_MAX) {
	DEBUG_WARN("%px: Failed to get %s interfaces list\n",
	ci, ecm_db_obj_dir_strings[obj_dir]);
	goto next;
	}

	/*
	* Inner most interface has the IP address, so we should get that interface.
	*/
	ecm_dev = dev_get_by_index(&init_net,
	ecm_db_iface_interface_identifier_get(interfaces[ECM_DB_IFACE_HEIRARCHY_MAX - 1]));
	if (!ecm_dev) {
	DEBUG_WARN("%px: unable to find ecm netdevice\n", ci);
	ecm_db_connection_interfaces_deref(interfaces, if_first);
	goto next;
	}
	ecm_db_connection_interfaces_deref(interfaces, if_first);

	fc_dev = dev_get_by_index(&init_net, cfg->fc_ifindex);
	if (!fc_dev) {
	DEBUG_WARN("%px: unable to find fib6_config netdevice\n", ci);
	dev_put(ecm_dev);
	goto next;
	}

	/*
	* Compare the ECM connection's netdevice with the route change config's netdevice.
	* If they are different, this means the new route effected the connection. So, defunct it.
	*/
	if (ecm_dev != fc_dev) {
	DEBUG_TRACE("%px: fib6_config dev: %s is different from ecm dev: %s, defunct the connection\n",
	ci, fc_dev->name, ecm_dev->name);
	ecm_db_connection_make_defunct(ci);
	}
	dev_put(fc_dev);
	dev_put(ecm_dev);
	next:
	cin = ecm_db_connection_get_and_ref_next(ci);
	ecm_db_connection_deref(ci);
	ci = cin;
	}

	/*
	* Re-enable IPv6 frontend processing.
	*/
	ecm_front_end_ipv6_stop(0);
	return NOTIFY_DONE;
	}

	static struct notifier_block ecm_db_ip6route_table_update_nb = {
	.notifier_call = ecm_db_ipv6_route_table_update_event,
	};
	#endif

	/*
	* ecm_db_init()
	*/
	int ecm_db_init(struct dentry *dentry)
	{
	DEBUG_INFO("ECM Module init\n");

	ecm_db_dentry = debugfs_create_dir("ecm_db", dentry);
	if (!ecm_db_dentry) {
	DEBUG_ERROR("Failed to create ecm db directory in debugfs\n");
	return -1;
	}

	/*
	* Get a random seed for jhash()
	*/
	get_random_bytes(&ecm_db_jhash_rnd, sizeof(ecm_db_jhash_rnd));
	printk(KERN_INFO "ECM database jhash random seed: 0x%x\n", ecm_db_jhash_rnd);

	if (!ecm_db_connection_init(ecm_db_dentry)) {
	goto init_cleanup;
	}

	if (!ecm_db_host_init(ecm_db_dentry)) {
	goto init_cleanup_1;
	}

	if (!ecm_db_mapping_init(ecm_db_dentry)) {
	goto init_cleanup_2;
	}

	if (!ecm_db_node_init(ecm_db_dentry)) {
	goto init_cleanup_3;
	}

	if (!ecm_db_iface_init(ecm_db_dentry)) {
	goto init_cleanup_4;
	}

	if (!debugfs_create_file("defunct_all", S_IRUGO \| S_IWUSR, ecm_db_dentry,
	NULL, &ecm_db_defunct_all_fops)) {
	DEBUG_ERROR("Failed to create ecm db defunct_all file in debugfs\n");
	goto init_cleanup_4;
	}

	ecm_db_li = ecm_db_listener_alloc();
	if (!ecm_db_li) {
	DEBUG_ERROR("%px: Failed to allocate a listener instance\n", dentry);
	goto init_cleanup_4;
	}
	ecm_db_listener_add(ecm_db_li,
	NULL, /* ecm_notifier_iface_added */
	NULL, /* ecm_notifier_iface_removed */
	NULL, /* ecm_notifier_node_added */
	NULL, /* ecm_notifier_node_removed */
	NULL, /* ecm_notifier_host_added */
	NULL, /* ecm_notifier_host_removed */
	NULL, /* ecm_notifier_mapping_added */
	NULL, /* ecm_notifier_mapping_removed */
	ecm_notifier_connection_added,
	ecm_notifier_connection_removed,
	NULL, /* ecm_notifier_connection_final */
	NULL);

	/*
	* Initialize the timer resources.
	*/
	ecm_db_timer_init();

	/*
	* register for route table modification events
	*/
	ip_rt_register_notifier(&ecm_db_iproute_table_update_nb);
	#ifdef ECM_IPV6_ENABLE
	rt6_register_notifier(&ecm_db_ip6route_table_update_nb);
	#endif
	return 0;

	init_cleanup_4:
	ecm_db_node_exit();
	init_cleanup_3:
	ecm_db_mapping_exit();
	init_cleanup_2:
	ecm_db_host_exit();
	init_cleanup_1:
	ecm_db_connection_exit();
	init_cleanup:
	debugfs_remove_recursive(ecm_db_dentry);
	return -1;
	}
	EXPORT_SYMBOL(ecm_db_init);

	/*
	* ecm_db_exit()
	*/
	void ecm_db_exit(void)
	{
	DEBUG_INFO("ECM DB Module exit\n");

	spin_lock_bh(&ecm_db_lock);
	ecm_db_terminate_pending = true;
	spin_unlock_bh(&ecm_db_lock);

	/*
	* unregister for route table update events
	*/
	ip_rt_unregister_notifier(&ecm_db_iproute_table_update_nb);
	#ifdef ECM_IPV6_ENABLE
	rt6_unregister_notifier(&ecm_db_ip6route_table_update_nb);
	#endif
	ecm_db_connection_defunct_all();

	/*
	* Clean-up the timer resources.
	*/
	ecm_db_timer_exit();

	if (ecm_db_li) {
	ecm_db_listener_deref(ecm_db_li);
	ecm_db_li = NULL;
	}

	/*
	* Free the database.
	*/
	ecm_db_node_exit();
	ecm_db_mapping_exit();
	ecm_db_host_exit();
	ecm_db_connection_exit();

	/*
	* Remove the debugfs files recursively.
	*/
	if (ecm_db_dentry) {
	debugfs_remove_recursive(ecm_db_dentry);
	}
	}
	EXPORT_SYMBOL(ecm_db_exit);