1 files changed, 370 insertions, 0 deletions

diff --git a/source4/cluster/ctdb/tcp/tcp_connect.c b/source4/cluster/ctdb/tcp/tcp_connect.c
new file mode 100644
index 0000000000..2f828e5717
--- /dev/null
+++ b/source4/cluster/ctdb/tcp/tcp_connect.c
@@ -0,0 +1,370 @@
+/* 
+   ctdb over TCP
+
+   Copyright (C) Andrew Tridgell  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 3 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, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+#include "lib/events/events.h"
+#include "lib/tdb/include/tdb.h"
+#include "system/network.h"
+#include "system/filesys.h"
+#include "../include/ctdb_private.h"
+#include "ctdb_tcp.h"
+
+/*
+  called when a complete packet has come in - should not happen on this socket
+ */
+void ctdb_tcp_tnode_cb(uint8_t *data, size_t cnt, void *private_data)
+{
+	struct ctdb_node *node = talloc_get_type(private_data, struct ctdb_node);
+	struct ctdb_tcp_node *tnode = talloc_get_type(
+		node->private_data, struct ctdb_tcp_node);
+
+	if (data == NULL) {
+		node->ctdb->upcalls->node_dead(node);
+	}
+
+	/* start a new connect cycle to try to re-establish the
+	   link */
+	ctdb_queue_set_fd(tnode->out_queue, -1);
+	tnode->fd = -1;
+	event_add_timed(node->ctdb->ev, tnode, timeval_zero(), 
+			ctdb_tcp_node_connect, node);
+}
+
+/*
+  called when socket becomes writeable on connect
+*/
+static void ctdb_node_connect_write(struct event_context *ev, struct fd_event *fde, 
+				    uint16_t flags, void *private_data)
+{
+	struct ctdb_node *node = talloc_get_type(private_data,
+						 struct ctdb_node);
+	struct ctdb_tcp_node *tnode = talloc_get_type(node->private_data,
+						      struct ctdb_tcp_node);
+	struct ctdb_context *ctdb = node->ctdb;
+	int error = 0;
+	socklen_t len = sizeof(error);
+	int one = 1;
+
+	talloc_free(tnode->connect_te);
+	tnode->connect_te = NULL;
+
+	if (getsockopt(tnode->fd, SOL_SOCKET, SO_ERROR, &error, &len) != 0 ||
+	    error != 0) {
+		talloc_free(fde);
+		close(tnode->fd);
+		tnode->fd = -1;
+		event_add_timed(ctdb->ev, tnode, timeval_current_ofs(1, 0), 
+				ctdb_tcp_node_connect, node);
+		return;
+	}
+
+	talloc_free(fde);
+	
+        setsockopt(tnode->fd,IPPROTO_TCP,TCP_NODELAY,(char *)&one,sizeof(one));
+        setsockopt(tnode->fd,SOL_SOCKET,SO_KEEPALIVE,(char *)&one,sizeof(one));
+
+	ctdb_queue_set_fd(tnode->out_queue, tnode->fd);
+
+	/* tell the ctdb layer we are connected */
+	node->ctdb->upcalls->node_connected(node);
+}
+
+
+static int ctdb_tcp_get_address(struct ctdb_context *ctdb,
+				const char *address, struct in_addr *addr)
+{
+	if (inet_pton(AF_INET, address, addr) <= 0) {
+		struct hostent *he = gethostbyname(address);
+		if (he == NULL || he->h_length > sizeof(*addr)) {
+			ctdb_set_error(ctdb, "invalid nework address '%s'\n", 
+				       address);
+			return -1;
+		}
+		memcpy(addr, he->h_addr, he->h_length);
+	}
+	return 0;
+}
+
+/*
+  called when we should try and establish a tcp connection to a node
+*/
+void ctdb_tcp_node_connect(struct event_context *ev, struct timed_event *te, 
+			   struct timeval t, void *private_data)
+{
+	struct ctdb_node *node = talloc_get_type(private_data,
+						 struct ctdb_node);
+	struct ctdb_tcp_node *tnode = talloc_get_type(node->private_data, 
+						      struct ctdb_tcp_node);
+	struct ctdb_context *ctdb = node->ctdb;
+        struct sockaddr_in sock_in;
+        struct sockaddr_in sock_out;
+
+	if (tnode->fd != -1) {
+		talloc_free(tnode->connect_fde);
+		tnode->connect_fde = NULL;
+		close(tnode->fd);
+		tnode->fd = -1;
+	}
+
+	tnode->fd = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
+
+	set_nonblocking(tnode->fd);
+	set_close_on_exec(tnode->fd);
+
+	ZERO_STRUCT(sock_out);
+#ifdef HAVE_SOCK_SIN_LEN
+	sock_out.sin_len = sizeof(sock_out);
+#endif
+	if (ctdb_tcp_get_address(ctdb, node->address.address, &sock_out.sin_addr) != 0) {
+		return;
+	}
+	sock_out.sin_port = htons(node->address.port);
+	sock_out.sin_family = PF_INET;
+
+
+	/* Bind our side of the socketpair to the same address we use to listen
+	 * on incoming CTDB traffic.
+	 * We must specify this address to make sure that the address we expose to
+	 * the remote side is actually routable in case CTDB traffic will run on
+	 * a dedicated non-routeable network.
+	 */
+	ZERO_STRUCT(sock_in);
+#ifdef HAVE_SOCK_SIN_LEN
+	sock_in.sin_len = sizeof(sock_in);
+#endif
+	if (ctdb_tcp_get_address(ctdb, ctdb->address.address, &sock_in.sin_addr) != 0) {
+		return;
+	}
+	sock_in.sin_port = htons(0); /* INPORT_ANY is not always available */
+	sock_in.sin_family = PF_INET;
+	bind(tnode->fd, (struct sockaddr *)&sock_in, sizeof(sock_in));
+
+	if (connect(tnode->fd, (struct sockaddr *)&sock_out, sizeof(sock_out)) != 0 &&
+	    errno != EINPROGRESS) {
+		/* try again once a second */
+		close(tnode->fd);
+		tnode->fd = -1;
+		event_add_timed(ctdb->ev, tnode, timeval_current_ofs(1, 0), 
+				ctdb_tcp_node_connect, node);
+		return;
+	}
+
+	/* non-blocking connect - wait for write event */
+	tnode->connect_fde = event_add_fd(node->ctdb->ev, tnode, tnode->fd, 
+					  EVENT_FD_WRITE|EVENT_FD_READ, 
+					  ctdb_node_connect_write, node);
+
+	/* don't give it long to connect - retry in one second. This ensures
+	   that we find a node is up quickly (tcp normally backs off a syn reply
+	   delay by quite a lot) */
+	tnode->connect_te = event_add_timed(ctdb->ev, tnode, timeval_current_ofs(1, 0), 
+					    ctdb_tcp_node_connect, node);
+}
+
+/*
+  called when we get contacted by another node
+  currently makes no attempt to check if the connection is really from a ctdb
+  node in our cluster
+*/
+static void ctdb_listen_event(struct event_context *ev, struct fd_event *fde, 
+			      uint16_t flags, void *private_data)
+{
+	struct ctdb_context *ctdb = talloc_get_type(private_data, struct ctdb_context);
+	struct ctdb_tcp *ctcp = talloc_get_type(ctdb->private_data, struct ctdb_tcp);
+	struct sockaddr_in addr;
+	socklen_t len;
+	int fd, nodeid;
+	struct ctdb_incoming *in;
+	int one = 1;
+	const char *incoming_node;
+
+	memset(&addr, 0, sizeof(addr));
+	len = sizeof(addr);
+	fd = accept(ctcp->listen_fd, (struct sockaddr *)&addr, &len);
+	if (fd == -1) return;
+
+	incoming_node = inet_ntoa(addr.sin_addr);
+	for (nodeid=0;nodeid<ctdb->num_nodes;nodeid++) {
+		if (!strcmp(incoming_node, ctdb->nodes[nodeid]->address.address)) {
+			DEBUG(0, ("Incoming connection from node:%d %s\n",nodeid,incoming_node));
+			break;
+		}
+	}
+	if (nodeid>=ctdb->num_nodes) {
+		DEBUG(0, ("Refused connection from unknown node %s\n", incoming_node));
+		close(fd);
+		return;
+	}
+
+	in = talloc_zero(ctcp, struct ctdb_incoming);
+	in->fd = fd;
+	in->ctdb = ctdb;
+
+	set_nonblocking(in->fd);
+	set_close_on_exec(in->fd);
+
+        setsockopt(in->fd,SOL_SOCKET,SO_KEEPALIVE,(char *)&one,sizeof(one));
+
+	in->queue = ctdb_queue_setup(ctdb, in, in->fd, CTDB_TCP_ALIGNMENT, 
+				     ctdb_tcp_read_cb, in);
+}
+
+
+/*
+  automatically find which address to listen on
+*/
+static int ctdb_tcp_listen_automatic(struct ctdb_context *ctdb)
+{
+	struct ctdb_tcp *ctcp = talloc_get_type(ctdb->private_data,
+						struct ctdb_tcp);
+        struct sockaddr_in sock;
+	int lock_fd, i;
+	const char *lock_path = "/tmp/.ctdb_socket_lock";
+	struct flock lock;
+
+	/* in order to ensure that we don't get two nodes with the
+	   same adddress, we must make the bind() and listen() calls
+	   atomic. The SO_REUSEADDR setsockopt only prevents double
+	   binds if the first socket is in LISTEN state  */
+	lock_fd = open(lock_path, O_RDWR|O_CREAT, 0666);
+	if (lock_fd == -1) {
+		DEBUG(0,("Unable to open %s\n", lock_path));
+		return -1;
+	}
+
+	lock.l_type = F_WRLCK;
+	lock.l_whence = SEEK_SET;
+	lock.l_start = 0;
+	lock.l_len = 1;
+	lock.l_pid = 0;
+
+	if (fcntl(lock_fd, F_SETLKW, &lock) != 0) {
+		DEBUG(0,("Unable to lock %s\n", lock_path));
+		close(lock_fd);
+		return -1;
+	}
+
+	for (i=0;i<ctdb->num_nodes;i++) {
+		ZERO_STRUCT(sock);
+#ifdef HAVE_SOCK_SIN_LEN
+		sock.sin_len = sizeof(sock);
+#endif
+		sock.sin_port = htons(ctdb->nodes[i]->address.port);
+		sock.sin_family = PF_INET;
+		if (ctdb_tcp_get_address(ctdb, ctdb->nodes[i]->address.address, 
+					 &sock.sin_addr) != 0) {
+			continue;
+		}
+		
+		if (bind(ctcp->listen_fd, (struct sockaddr * )&sock, 
+			 sizeof(sock)) == 0) {
+			break;
+		}
+	}
+	
+	if (i == ctdb->num_nodes) {
+		DEBUG(0,("Unable to bind to any of the node addresses - giving up\n"));
+		goto failed;
+	}
+	ctdb->address = ctdb->nodes[i]->address;
+	ctdb->name = talloc_asprintf(ctdb, "%s:%u", 
+				     ctdb->address.address, 
+				     ctdb->address.port);
+	ctdb->vnn = ctdb->nodes[i]->vnn;
+	ctdb->nodes[i]->flags &= ~NODE_FLAGS_DISCONNECTED;
+	DEBUG(1,("ctdb chose network address %s:%u vnn %u\n", 
+		 ctdb->address.address, 
+		 ctdb->address.port, 
+		 ctdb->vnn));
+
+	if (listen(ctcp->listen_fd, 10) == -1) {
+		goto failed;
+	}
+
+	event_add_fd(ctdb->ev, ctcp, ctcp->listen_fd, EVENT_FD_READ|EVENT_FD_AUTOCLOSE, 
+		     ctdb_listen_event, ctdb);	
+
+	close(lock_fd);
+	return 0;
+	
+failed:
+	close(lock_fd);
+	close(ctcp->listen_fd);
+	ctcp->listen_fd = -1;
+	return -1;
+}
+
+
+/*
+  listen on our own address
+*/
+int ctdb_tcp_listen(struct ctdb_context *ctdb)
+{
+	struct ctdb_tcp *ctcp = talloc_get_type(ctdb->private_data,
+						struct ctdb_tcp);
+        struct sockaddr_in sock;
+	int one = 1;
+
+	ctcp->listen_fd = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
+	if (ctcp->listen_fd == -1) {
+		ctdb_set_error(ctdb, "socket failed\n");
+		return -1;
+	}
+
+	set_close_on_exec(ctcp->listen_fd);
+
+        setsockopt(ctcp->listen_fd,SOL_SOCKET,SO_REUSEADDR,(char *)&one,sizeof(one));
+
+	/* we can either auto-bind to the first available address, or we can
+	   use a specified address */
+	if (!ctdb->address.address) {
+		return ctdb_tcp_listen_automatic(ctdb);
+	}
+
+	ZERO_STRUCT(sock);
+#ifdef HAVE_SOCK_SIN_LEN
+	sock.sin_len = sizeof(sock);
+#endif
+	sock.sin_port = htons(ctdb->address.port);
+	sock.sin_family = PF_INET;
+	
+	if (ctdb_tcp_get_address(ctdb, ctdb->address.address, 
+				 &sock.sin_addr) != 0) {
+		goto failed;
+	}
+	
+	if (bind(ctcp->listen_fd, (struct sockaddr * )&sock, sizeof(sock)) != 0) {
+		goto failed;
+	}
+
+	if (listen(ctcp->listen_fd, 10) == -1) {
+		goto failed;
+	}
+
+	event_add_fd(ctdb->ev, ctcp, ctcp->listen_fd, EVENT_FD_READ|EVENT_FD_AUTOCLOSE, 
+		     ctdb_listen_event, ctdb);	
+
+	return 0;
+
+failed:
+	close(ctcp->listen_fd);
+	ctcp->listen_fd = -1;
+	return -1;
+}
+