1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
|
/*
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 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 "includes.h"
#include "process_model.h"
#include "events.h"
#include "smbd/service_stream.h"
/* the range of ports to try for dcerpc over tcp endpoints */
#define SERVER_TCP_LOW_PORT 1024
#define SERVER_TCP_HIGH_PORT 1300
/* 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 event_context *event_ctx;
const struct model_ops *model_ops;
struct socket_context *sock;
void *private;
};
/*
close the socket and shutdown a stream_connection
*/
void stream_terminate_connection(struct stream_connection *srv_conn, const char *reason)
{
struct event_ctx *event_ctx = srv_conn->event.ctx;
const struct model_ops *model_ops = srv_conn->model_ops;
talloc_free(srv_conn);
model_ops->terminate(event_ctx, reason);
}
/*
the select loop has indicated that a stream is ready for IO
*/
static void stream_io_handler(struct event_context *ev, struct fd_event *fde,
struct timeval t, uint16_t flags)
{
struct stream_connection *conn = talloc_get_type(fde->private,
struct stream_connection);
if (flags & EVENT_FD_WRITE) {
conn->ops->send_handler(conn, t, flags);
return;
}
if (flags & EVENT_FD_READ) {
conn->ops->recv_handler(conn, t, flags);
}
}
/*
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 event_context *ev,
struct socket_context *sock,
uint32_t server_id, void *private)
{
struct stream_socket *stream_socket = talloc_get_type(private, struct stream_socket);
struct fd_event fde;
struct stream_connection *srv_conn;
srv_conn = talloc_zero(ev, struct stream_connection);
if (!srv_conn) {
DEBUG(0,("talloc(mem_ctx, struct stream_connection) failed\n"));
return;
}
talloc_steal(srv_conn, sock);
fde.private = srv_conn;
fde.fd = socket_get_fd(sock);
fde.flags = EVENT_FD_READ;
fde.handler = stream_io_handler;
srv_conn->private = stream_socket->private;
srv_conn->model_ops = stream_socket->model_ops;
srv_conn->event.ctx = ev;
srv_conn->event.fde = &fde;
srv_conn->socket = sock;
srv_conn->server_id = server_id;
srv_conn->ops = stream_socket->ops;
srv_conn->event.fde = event_add_fd(ev, &fde, srv_conn);
if (!socket_check_access(sock, "smbd", lp_hostsallow(-1), lp_hostsdeny(-1))) {
stream_terminate_connection(srv_conn, "denied by access rules");
return;
}
/* setup to receive internal messages on this connection */
srv_conn->msg_ctx = messaging_init(srv_conn, srv_conn->server_id, ev);
if (!srv_conn->msg_ctx) {
stream_terminate_connection(srv_conn, "messaging_init() failed");
return;
}
/* 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 event_context *ev, struct fd_event *fde,
struct timeval t, uint16_t flags)
{
struct stream_socket *stream_socket = talloc_get_type(fde->private, 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->sock,
stream_new_connection, stream_socket);
}
/*
setup a listen stream socket
if you pass *port == 0, then a port > 1024 is used
*/
NTSTATUS stream_setup_socket(struct event_context *event_context,
const struct model_ops *model_ops,
const struct stream_server_ops *stream_ops,
const char *family,
const char *sock_addr,
uint16_t *port,
void *private)
{
NTSTATUS status;
struct stream_socket *stream_socket;
struct fd_event fde;
int i;
stream_socket = talloc_zero(event_context, struct stream_socket);
NT_STATUS_HAVE_NO_MEMORY(stream_socket);
status = socket_create(family, SOCKET_TYPE_STREAM, &stream_socket->sock, 0);
NT_STATUS_NOT_OK_RETURN(status);
talloc_steal(stream_socket, stream_socket->sock);
/* ready to listen */
status = socket_set_option(stream_socket->sock, "SO_KEEPALIVE", NULL);
NT_STATUS_NOT_OK_RETURN(status);
status = socket_set_option(stream_socket->sock, lp_socket_options(), NULL);
NT_STATUS_NOT_OK_RETURN(status);
/* TODO: set socket ACL's here when they're implemented */
if (*port == 0) {
for (i=SERVER_TCP_LOW_PORT;i<= SERVER_TCP_HIGH_PORT;i++) {
status = socket_listen(stream_socket->sock, sock_addr, i,
SERVER_LISTEN_BACKLOG, 0);
if (NT_STATUS_IS_OK(status)) {
*port = i;
break;
}
}
} else {
status = socket_listen(stream_socket->sock, sock_addr, *port, SERVER_LISTEN_BACKLOG, 0);
}
if (!NT_STATUS_IS_OK(status)) {
DEBUG(0,("Failed to listen on %s:%u - %s\n",
sock_addr, *port, nt_errstr(status)));
talloc_free(stream_socket);
return status;
}
/* we are only interested in read events on the listen socket */
fde.fd = socket_get_fd(stream_socket->sock);
fde.flags = EVENT_FD_READ;
fde.private = stream_socket;
fde.handler = stream_accept_handler;
event_add_fd(event_context, &fde, stream_socket->sock);
stream_socket->private = talloc_reference(stream_socket, private);
stream_socket->ops = stream_ops;
stream_socket->event_ctx = event_context;
stream_socket->model_ops = model_ops;
return NT_STATUS_OK;
}
|
