add best effort replication protocol (aka NOTRACK)

5 files changed, 203 insertions, 2 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 554074f..69ddcfd 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -15,7 +15,7 @@ conntrackd_SOURCES = alarm.c main.c run.c hash.c queue.c rbtree.c \
 		    ignore_pool.c fds.c event.c \
 		    cache.c cache_iterators.c \
 		    cache_lifetime.c cache_timer.c cache_wt.c \
-		    sync-mode.c sync-alarm.c sync-ftfw.c \
+		    sync-mode.c sync-alarm.c sync-ftfw.c sync-notrack.c \
 		    traffic_stats.c stats-mode.c \
 		    network.c \
 		    state_helper.c state_helper_tcp.c \
diff --git a/src/read_config_lex.l b/src/read_config_lex.l
index 7daaeab..bdde3b6 100644
--- a/src/read_config_lex.l
+++ b/src/read_config_lex.l
@@ -49,6 +49,7 @@ persistent	[P|p][E|e][R|r][S|s][I|i][S|s][T|t][E|e][N|n][T|T]
 nack		[N|n][A|a][C|c][K|k]
 alarm		[A|a][L|l][A|a][R|r][M|m]
 ftfw		[F|f][T|t][F|f][W|w]
+notrack		[N|n][O|o][T|t][R|r][A|a][C|c][K|k]
 
 %%
 "UNIX"				{ return T_UNIX; }
@@ -125,6 +126,7 @@ ftfw		[F|f][T|t][F|f][W|w]
 				  "is called `ftfw'. Please, update "
 				  "your conntrackd.conf file.\n");
 			  return T_FTFW; }
+{notrack}		{ return T_NOTRACK; }
 {string}		{ yylval.string = strdup(yytext); return T_STRING; }
 
 {comment}	;
diff --git a/src/read_config_yy.y b/src/read_config_yy.y
index 7fb3d5b..b9c53be 100644
--- a/src/read_config_yy.y
+++ b/src/read_config_yy.y
@@ -53,7 +53,7 @@ struct ct_conf conf;
 %token T_ESTABLISHED T_SYN_SENT T_SYN_RECV T_FIN_WAIT 
 %token T_CLOSE_WAIT T_LAST_ACK T_TIME_WAIT T_CLOSE T_LISTEN
 %token T_SYSLOG T_WRITE_THROUGH T_STAT_BUFFER_SIZE T_DESTROY_TIMEOUT
-%token T_MCAST_RCVBUFF T_MCAST_SNDBUFF
+%token T_MCAST_RCVBUFF T_MCAST_SNDBUFF T_NOTRACK
 
 %token <string> T_IP T_PATH_VAL
 %token <val> T_NUMBER
@@ -436,6 +436,7 @@ sync_line: refreshtime
 	 | delay_destroy_msgs
 	 | sync_mode_alarm
 	 | sync_mode_ftfw
+	 | sync_mode_notrack
 	 | listen_to
 	 | state_replication
 	 | cache_writethrough
@@ -452,6 +453,11 @@ sync_mode_ftfw: T_SYNC_MODE T_FTFW '{' sync_mode_ftfw_list '}'
 	conf.flags |= CTD_SYNC_FTFW;
 };
 
+sync_mode_notrack: T_SYNC_MODE T_NOTRACK '{' sync_mode_notrack_list '}'
+{
+	conf.flags |= CTD_SYNC_NOTRACK;
+};
+
 sync_mode_alarm_list:
 	      | sync_mode_alarm_list sync_mode_alarm_line;
 
@@ -470,6 +476,13 @@ sync_mode_ftfw_line: resend_queue_size
 		   | window_size
 		   ;
 
+sync_mode_notrack_list:
+	      | sync_mode_notrack_list sync_mode_notrack_line;
+
+sync_mode_notrack_line: timeout
+		   ;
+
+
 resend_queue_size: T_RESEND_BUFFER_SIZE T_NUMBER
 {
 	conf.resend_queue_size = $2;
diff --git a/src/sync-mode.c b/src/sync-mode.c
index 2fe7406..16cc70d 100644
--- a/src/sync-mode.c
+++ b/src/sync-mode.c
@@ -169,6 +169,8 @@ static int init_sync(void)
 		STATE_SYNC(sync) = &sync_ftfw;
 	else if (CONFIG(flags) & CTD_SYNC_ALARM)
 		STATE_SYNC(sync) = &sync_alarm;
+	else if (CONFIG(flags) & CTD_SYNC_NOTRACK)
+		STATE_SYNC(sync) = &sync_notrack;
 	else {
 		fprintf(stderr, "WARNING: No synchronization mode specified. "
 				"Defaulting to FT-FW mode.\n");
diff --git a/src/sync-notrack.c b/src/sync-notrack.c
new file mode 100644
index 0000000..2b1bc13
--- /dev/null
+++ b/src/sync-notrack.c
@@ -0,0 +1,184 @@
+/*
+ * (C) 2008 by Pablo Neira Ayuso <pablo@netfilter.org>
+ * 
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "conntrackd.h"
+#include "sync.h"
+#include "us-conntrack.h"
+#include "queue.h"
+#include "debug.h"
+#include "network.h"
+#include "log.h"
+#include "cache.h"
+#include "event.h"
+
+#include <string.h>
+
+static LIST_HEAD(tx_list);
+static unsigned int tx_list_len;
+static struct queue *tx_queue;
+
+struct cache_notrack {
+	struct list_head	tx_list;
+};
+
+static struct cache_extra cache_notrack_extra = {
+	.size 		= sizeof(struct cache_notrack),
+};
+
+static void tx_queue_add_ctlmsg(uint32_t flags, uint32_t from, uint32_t to)
+{
+	struct nethdr_ack ack = {
+		.flags = flags,
+		.from  = from,
+		.to    = to,
+	};
+
+	queue_add(tx_queue, &ack, NETHDR_ACK_SIZ);
+	write_evfd(STATE_SYNC(evfd));
+}
+
+static int notrack_init(void)
+{
+	tx_queue = queue_create(~0U);
+	if (tx_queue == NULL) {
+		dlog(LOG_ERR, "cannot create tx queue");
+		return -1;
+	}
+
+	return 0;
+}
+
+static void notrack_kill(void)
+{
+	queue_destroy(tx_queue);
+}
+
+static int do_cache_to_tx(void *data1, void *data2)
+{
+	struct us_conntrack *u = data2;
+	struct cache_notrack *cn = cache_get_extra(STATE_SYNC(internal), u);
+
+	/* add to tx list */
+	list_add_tail(&cn->tx_list, &tx_list);
+	tx_list_len++;
+
+	write_evfd(STATE_SYNC(evfd));
+
+	return 0;
+}
+
+static int notrack_local(int fd, int type, void *data)
+{
+	int ret = 1;
+
+	switch(type) {
+	case REQUEST_DUMP:
+		dlog(LOG_NOTICE, "request resync");
+		tx_queue_add_ctlmsg(NET_F_RESYNC, 0, 0);
+		break;
+	case SEND_BULK:
+		dlog(LOG_NOTICE, "sending bulk update");
+		cache_iterate(STATE_SYNC(internal), NULL, do_cache_to_tx);
+		break;
+	default:
+		ret = 0;
+		break;
+	}
+
+	return ret;
+}
+
+static int digest_msg(const struct nethdr *net)
+{
+	if (IS_DATA(net))
+		return MSG_DATA;
+
+	if (IS_RESYNC(net)) {
+		cache_iterate(STATE_SYNC(internal), NULL, do_cache_to_tx);
+		return MSG_CTL;
+	}
+
+	return MSG_BAD;
+}
+
+static int notrack_recv(const struct nethdr *net)
+{
+	int ret;
+	unsigned int exp_seq;
+
+	mcast_track_seq(net->seq, &exp_seq);
+
+	ret = digest_msg(net);
+
+	if (ret != MSG_BAD)
+		mcast_track_update_seq(net->seq);
+
+	return ret;
+}
+
+static int tx_queue_xmit(void *data1, const void *data2)
+{
+	struct nethdr *net = data1;
+	size_t len = prepare_send_netmsg(STATE_SYNC(mcast_client), net);
+
+	mcast_buffered_send_netmsg(STATE_SYNC(mcast_client), net, len);
+	queue_del(tx_queue, net);
+
+	return 0;
+}
+
+static int tx_list_xmit(struct list_head *i, struct us_conntrack *u, int type)
+{
+	int ret;
+	struct nethdr *net = BUILD_NETMSG(u->ct, type);
+	size_t len = prepare_send_netmsg(STATE_SYNC(mcast_client), net);
+
+	list_del_init(i);
+	tx_list_len--;
+
+	ret = mcast_buffered_send_netmsg(STATE_SYNC(mcast_client), net, len);
+
+	return ret;
+}
+
+static void notrack_run(void)
+{
+	struct cache_notrack *cn, *tmp;
+
+	/* send messages in the tx_queue */
+	queue_iterate(tx_queue, NULL, tx_queue_xmit);
+
+	/* send conntracks in the tx_list */
+	list_for_each_entry_safe(cn, tmp, &tx_list, tx_list) {
+		struct us_conntrack *u;
+
+		u = cache_get_conntrack(STATE_SYNC(internal), cn);
+		tx_list_xmit(&cn->tx_list, u, NFCT_Q_UPDATE);
+	}
+}
+
+struct sync_mode sync_notrack = {
+	.internal_cache_flags	= LIFETIME,
+	.external_cache_flags	= LIFETIME,
+	.internal_cache_extra	= &cache_notrack_extra,
+	.init			= notrack_init,
+	.kill			= notrack_kill,
+	.local			= notrack_local,
+	.recv			= notrack_recv,
+	.run			= notrack_run,
+};