1 files changed, 413 insertions, 0 deletions

diff --git a/source4/samba/service_stream.c b/source4/samba/service_stream.c
new file mode 100644
index 0000000..458ebcf
--- /dev/null
+++ b/source4/samba/service_stream.c
@@ -0,0 +1,413 @@
+/* 
+   Unix SMB/CIFS implementation.
+
+   helper functions for stream based servers
+
+   Copyright (C) Andrew Tridgell 2003-2005
+   Copyright (C) Stefan (metze) Metzmacher	2004
+   
+   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 <tevent.h>
+#include "process_model.h"
+#include "lib/util/server_id.h"
+#include "lib/messaging/irpc.h"
+#include "cluster/cluster.h"
+#include "param/param.h"
+#include "../lib/tsocket/tsocket.h"
+#include "lib/util/util_net.h"
+
+/* size of listen() backlog in smbd */
+#define SERVER_LISTEN_BACKLOG 10
+
+
+/*
+  private structure for a single listening stream socket
+*/
+struct stream_socket {
+	const struct stream_server_ops *ops;
+	struct loadparm_context *lp_ctx;
+	struct tevent_context *event_ctx;
+	const struct model_ops *model_ops;
+	struct socket_context *sock;
+	void *private_data;
+	void *process_context;
+};
+
+
+/*
+  close the socket and shutdown a stream_connection
+*/
+void stream_terminate_connection(struct stream_connection *srv_conn, const char *reason)
+{
+	struct tevent_context *event_ctx = srv_conn->event.ctx;
+	const struct model_ops *model_ops = srv_conn->model_ops;
+	struct loadparm_context *lp_ctx = srv_conn->lp_ctx;
+	void *process_context = srv_conn->process_context;
+	TALLOC_CTX *frame = NULL;
+
+	if (!reason) reason = "unknown reason";
+
+	if (srv_conn->processing) {
+		DBG_NOTICE("Terminating connection deferred - '%s'\n", reason);
+	} else {
+		DBG_NOTICE("Terminating connection - '%s'\n", reason);
+	}
+
+	srv_conn->terminate = reason;
+
+	if (srv_conn->processing) {
+		/* 
+		 * if we're currently inside the stream_io_handler(),
+		 * defer the termination to the end of stream_io_hendler()
+		 *
+		 * and we don't want to read or write to the connection...
+		 */
+		tevent_fd_set_flags(srv_conn->event.fde, 0);
+		return;
+	}
+
+	frame = talloc_stackframe();
+
+	reason = talloc_strdup(frame, reason);
+	if (reason == NULL) {
+		reason = "OOM - unknown reason";
+	}
+
+	TALLOC_FREE(srv_conn->event.fde);
+	imessaging_cleanup(srv_conn->msg_ctx);
+	TALLOC_FREE(srv_conn);
+	model_ops->terminate_connection(
+	    event_ctx, lp_ctx, reason, process_context);
+	TALLOC_FREE(frame);
+}
+
+/**
+  the select loop has indicated that a stream is ready for IO
+*/
+static void stream_io_handler(struct stream_connection *conn, uint16_t flags)
+{
+	conn->processing++;
+	if (flags & TEVENT_FD_WRITE) {
+		conn->ops->send_handler(conn, flags);
+	} else if (flags & TEVENT_FD_READ) {
+		conn->ops->recv_handler(conn, flags);
+	}
+	conn->processing--;
+
+	if (conn->terminate) {
+		stream_terminate_connection(conn, conn->terminate);
+	}
+}
+
+void stream_io_handler_fde(struct tevent_context *ev, struct tevent_fd *fde,
+				  uint16_t flags, void *private_data)
+{
+	struct stream_connection *conn = talloc_get_type(private_data,
+							 struct stream_connection);
+	stream_io_handler(conn, flags);
+}
+
+void stream_io_handler_callback(void *private_data, uint16_t flags)
+{
+	struct stream_connection *conn = talloc_get_type(private_data,
+							 struct stream_connection);
+	stream_io_handler(conn, flags);
+}
+
+/*
+  this creates a stream_connection from an already existing connection,
+  used for protocols, where a client connection needs to switched into
+  a server connection
+*/
+NTSTATUS stream_new_connection_merge(struct tevent_context *ev,
+				     struct loadparm_context *lp_ctx,
+				     const struct model_ops *model_ops,
+				     const struct stream_server_ops *stream_ops,
+				     struct imessaging_context *msg_ctx,
+				     void *private_data,
+				     struct stream_connection **_srv_conn,
+				     void *process_context)
+{
+	struct stream_connection *srv_conn;
+
+	srv_conn = talloc_zero(ev, struct stream_connection);
+	NT_STATUS_HAVE_NO_MEMORY(srv_conn);
+
+	srv_conn->private_data    = private_data;
+	srv_conn->model_ops       = model_ops;
+	srv_conn->socket	  = NULL;
+	srv_conn->server_id	  = cluster_id(0, 0);
+	srv_conn->ops             = stream_ops;
+	srv_conn->msg_ctx	  = msg_ctx;
+	srv_conn->event.ctx	  = ev;
+	srv_conn->lp_ctx	  = lp_ctx;
+	srv_conn->event.fde	  = NULL;
+	srv_conn->process_context = process_context;
+
+	*_srv_conn = srv_conn;
+	return NT_STATUS_OK;
+}
+
+/*
+  called when a new socket connection has been established. This is called in the process
+  context of the new process (if appropriate)
+*/
+static void stream_new_connection(struct tevent_context *ev,
+				  struct loadparm_context *lp_ctx,
+				  struct socket_context *sock, 
+				  struct server_id server_id,
+				  void *private_data,
+				  void *process_context)
+{
+	struct stream_socket *stream_socket = talloc_get_type(private_data, struct stream_socket);
+	struct stream_connection *srv_conn;
+
+	srv_conn = talloc_zero(ev, struct stream_connection);
+	if (!srv_conn) {
+		DBG_ERR("talloc(mem_ctx, struct stream_connection) failed\n");
+		return;
+	}
+
+	talloc_steal(srv_conn, sock);
+
+	srv_conn->private_data	  = stream_socket->private_data;
+	srv_conn->model_ops       = stream_socket->model_ops;
+	srv_conn->socket	  = sock;
+	srv_conn->server_id	  = server_id;
+	srv_conn->ops             = stream_socket->ops;
+	srv_conn->event.ctx	  = ev;
+	srv_conn->lp_ctx	  = lp_ctx;
+	srv_conn->process_context = process_context;
+
+	if (!socket_check_access(sock, "smbd", lpcfg_hosts_allow(NULL, lpcfg_default_service(lp_ctx)), lpcfg_hosts_deny(NULL, lpcfg_default_service(lp_ctx)))) {
+		stream_terminate_connection(srv_conn, "denied by access rules");
+		return;
+	}
+
+	srv_conn->event.fde	= tevent_add_fd(ev, srv_conn, socket_get_fd(sock),
+						0, stream_io_handler_fde, srv_conn);
+	if (!srv_conn->event.fde) {
+		stream_terminate_connection(srv_conn, "tevent_add_fd() failed");
+		return;
+	}
+
+	/* setup to receive internal messages on this connection */
+	srv_conn->msg_ctx = imessaging_init(srv_conn,
+					    lp_ctx,
+					    srv_conn->server_id, ev);
+	if (!srv_conn->msg_ctx) {
+		stream_terminate_connection(srv_conn, "imessaging_init() failed");
+		return;
+	}
+
+	srv_conn->remote_address = socket_get_remote_addr(srv_conn->socket, srv_conn);
+	if (!srv_conn->remote_address) {
+		stream_terminate_connection(srv_conn, "socket_get_remote_addr() failed");
+		return;
+	}
+
+	srv_conn->local_address = socket_get_local_addr(srv_conn->socket, srv_conn);
+	if (!srv_conn->local_address) {
+		stream_terminate_connection(srv_conn, "socket_get_local_addr() failed");
+		return;
+	}
+
+	{
+		TALLOC_CTX *tmp_ctx;
+		const char *title;
+		struct server_id_buf idbuf;
+
+		tmp_ctx = talloc_new(srv_conn);
+
+		title = talloc_asprintf(tmp_ctx, "conn[%s] c[%s] s[%s] server_id[%s]",
+					stream_socket->ops->name, 
+					tsocket_address_string(srv_conn->remote_address, tmp_ctx),
+					tsocket_address_string(srv_conn->local_address, tmp_ctx),
+					server_id_str_buf(server_id, &idbuf));
+		if (title) {
+			stream_connection_set_title(srv_conn, title);
+		}
+		talloc_free(tmp_ctx);
+	}
+
+	/* we're now ready to start receiving events on this stream */
+	TEVENT_FD_READABLE(srv_conn->event.fde);
+
+	/* call the server specific accept code */
+	stream_socket->ops->accept_connection(srv_conn);
+}
+
+
+/*
+  called when someone opens a connection to one of our listening ports
+*/
+static void stream_accept_handler(struct tevent_context *ev, struct tevent_fd *fde, 
+				  uint16_t flags, void *private_data)
+{
+	struct stream_socket *stream_socket = talloc_get_type(private_data, struct stream_socket);
+
+	/* ask the process model to create us a process for this new
+	   connection.  When done, it calls stream_new_connection()
+	   with the newly created socket */
+	stream_socket->model_ops->accept_connection(
+		ev,
+		stream_socket->lp_ctx,
+		stream_socket->sock,
+		stream_new_connection,
+		stream_socket,
+		stream_socket->process_context);
+}
+
+/*
+  setup a listen stream socket
+  if you pass *port == 0, then a port > 1024 is used
+
+  FIXME: This function is TCP/IP specific - uses an int rather than 
+  	 a string for the port. Should leave allocating a port nr 
+         to the socket implementation - JRV20070903
+ */
+NTSTATUS stream_setup_socket(TALLOC_CTX *mem_ctx,
+			     struct tevent_context *event_context,
+			     struct loadparm_context *lp_ctx,
+			     const struct model_ops *model_ops,
+			     const struct stream_server_ops *stream_ops,
+			     const char *family,
+			     const char *sock_addr,
+			     uint16_t *port,
+			     const char *socket_options,
+			     void *private_data,
+			     void *process_context)
+{
+	NTSTATUS status;
+	struct stream_socket *stream_socket;
+	struct socket_address *socket_address;
+	struct tevent_fd *fde;
+	int i;
+	struct sockaddr_storage ss;
+
+	stream_socket = talloc_zero(mem_ctx, struct stream_socket);
+	NT_STATUS_HAVE_NO_MEMORY(stream_socket);
+
+	if (strcmp(family, "ip") == 0) {
+		/* we will get the real family from the address itself */
+		if (!interpret_string_addr(&ss, sock_addr, 0)) {
+			talloc_free(stream_socket);
+			return NT_STATUS_INVALID_ADDRESS;
+		}
+
+		socket_address = socket_address_from_sockaddr_storage(stream_socket, &ss, port?*port:0);
+		if (socket_address == NULL) {
+			TALLOC_FREE(stream_socket);
+			return NT_STATUS_NO_MEMORY;
+		}
+
+		status = socket_create(stream_socket, socket_address->family,
+				       SOCKET_TYPE_STREAM,
+				       &stream_socket->sock, 0);
+		NT_STATUS_NOT_OK_RETURN(status);
+	} else {
+		status = socket_create(stream_socket, family,
+				       SOCKET_TYPE_STREAM,
+				       &stream_socket->sock, 0);
+		NT_STATUS_NOT_OK_RETURN(status);
+
+		/* this is for non-IP sockets, eg. unix domain sockets */
+		socket_address = socket_address_from_strings(stream_socket,
+							     stream_socket->sock->backend_name,
+							     sock_addr, port?*port:0);
+		NT_STATUS_HAVE_NO_MEMORY(socket_address);
+	}
+
+
+	stream_socket->lp_ctx = talloc_reference(stream_socket, lp_ctx);
+
+	/* ready to listen */
+	status = socket_set_option(stream_socket->sock, "SO_KEEPALIVE", NULL);
+	NT_STATUS_NOT_OK_RETURN(status);
+
+	if (socket_options != NULL) {
+		status = socket_set_option(stream_socket->sock, socket_options, NULL);
+		NT_STATUS_NOT_OK_RETURN(status);
+	}
+
+	/* TODO: set socket ACL's (host allow etc) here when they're
+	 * implemented */
+
+	/* Some sockets don't have a port, or are just described from
+	 * the string.  We are indicating this by having port == NULL */
+	if (!port) {
+		status = socket_listen(stream_socket->sock, socket_address, SERVER_LISTEN_BACKLOG, 0);
+	} else if (*port == 0) {
+		for (i = lpcfg_rpc_low_port(lp_ctx);
+		     i <= lpcfg_rpc_high_port(lp_ctx);
+		     i++) {
+			socket_address->port = i;
+			status = socket_listen(stream_socket->sock, socket_address, 
+					       SERVER_LISTEN_BACKLOG, 0);
+			if (NT_STATUS_IS_OK(status)) {
+				*port = i;
+				break;
+			}
+		}
+	} else {
+		status = socket_listen(stream_socket->sock, socket_address, SERVER_LISTEN_BACKLOG, 0);
+	}
+
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_ERR("Failed to listen on %s:%u - %s\n",
+			 sock_addr, port ? (unsigned int)(*port) : 0,
+			 nt_errstr(status));
+		talloc_free(stream_socket);
+		return status;
+	}
+
+	/* Add the FD from the newly created socket into the event
+	 * subsystem.  it will call the accept handler whenever we get
+	 * new connections */
+
+	fde = tevent_add_fd(event_context, stream_socket->sock,
+			    socket_get_fd(stream_socket->sock),
+			    TEVENT_FD_READ,
+			    stream_accept_handler, stream_socket);
+	if (!fde) {
+		DBG_ERR("Failed to setup fd event\n");
+		talloc_free(stream_socket);
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	/* we let events system to the close on the socket. This avoids
+	 * nasty interactions with waiting for talloc to close the socket. */
+	tevent_fd_set_close_fn(fde, socket_tevent_fd_close_fn);
+	socket_set_flags(stream_socket->sock, SOCKET_FLAG_NOCLOSE);
+
+	stream_socket->private_data     = talloc_reference(stream_socket, private_data);
+	stream_socket->ops              = stream_ops;
+	stream_socket->event_ctx	= event_context;
+	stream_socket->model_ops        = model_ops;
+	stream_socket->process_context  = process_context;
+
+	return NT_STATUS_OK;
+}
+
+
+/*
+  setup a connection title 
+*/
+void stream_connection_set_title(struct stream_connection *conn, const char *title)
+{
+	conn->model_ops->set_title(conn->event.ctx, title);
+}