summaryrefslogtreecommitdiff
path: root/source4/web_server/web_server.c
blob: 9ff67f78f30da7458ee44af090b91d2154af3e0a (plain)
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
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
/* 
   Unix SMB/CIFS implementation.

   web server startup

   Copyright (C) Andrew Tridgell 2005
   
   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 "smbd/service_task.h"
#include "smbd/service_stream.h"
#include "smbd/service.h"
#include "web_server/web_server.h"
#include "lib/events/events.h"
#include "system/filesys.h"
#include "system/network.h"
#include "lib/socket/netif.h"
#include "lib/tls/tls.h"
#include "param/param.h"

/* don't allow connections to hang around forever */
#define HTTP_TIMEOUT 120

/*
  destroy a web connection
*/
static int websrv_destructor(struct websrv_context *web)
{
	if (web->output.fd != -1) {
		close(web->output.fd);
	}
	return 0;
}

/*
  called when a connection times out. This prevents a stuck connection
  from hanging around forever
*/
static void websrv_timeout(struct event_context *event_context, 
			   struct timed_event *te, 
			   struct timeval t, void *private)
{
	struct websrv_context *web = talloc_get_type(private, struct websrv_context);
	struct stream_connection *conn = web->conn;
	web->conn = NULL;
	/* TODO: send a message to any running esp context on this connection
	   to stop running */
	stream_terminate_connection(conn, "websrv_timeout: timed out");	
}

/*
  called when a web connection becomes readable
*/
static void websrv_recv(struct stream_connection *conn, uint16_t flags)
{
	struct websrv_context *web = talloc_get_type(conn->private, 
						     struct websrv_context);
	NTSTATUS status;
	uint8_t buf[1024];
	size_t nread;
	uint8_t *p;
	DATA_BLOB b;

	/* not the most efficient http parser ever, but good enough for us */
	status = socket_recv(conn->socket, buf, sizeof(buf), &nread);
	if (NT_STATUS_IS_ERR(status)) goto failed;
	if (!NT_STATUS_IS_OK(status)) return;

	if (!data_blob_append(web, &web->input.partial, buf, nread))
		goto failed;

	/* parse any lines that are available */
	b = web->input.partial;
	while (!web->input.end_of_headers &&
	       (p=(uint8_t *)memchr(b.data, '\n', b.length))) {
		const char *line = (const char *)b.data;
		*p = 0;
		if (p != b.data && p[-1] == '\r') {
			p[-1] = 0;
		}
		status = http_parse_header(web, line);
		if (!NT_STATUS_IS_OK(status)) return;
		b.length -= (p - b.data) + 1;
		b.data = p+1;
	}

	/* keep any remaining bytes in web->input.partial */
	if (b.length == 0) {
		b.data = NULL;
	}
	b = data_blob_talloc(web, b.data, b.length);
	data_blob_free(&web->input.partial);
	web->input.partial = b;

	/* we finish when we have both the full headers (terminated by
	   a blank line) and any post data, as indicated by the
	   content_length */
	if (web->input.end_of_headers &&
	    web->input.partial.length >= web->input.content_length) {
		if (web->input.partial.length > web->input.content_length) {
			web->input.partial.data[web->input.content_length] = 0;
		}
		EVENT_FD_NOT_READABLE(web->conn->event.fde);

		/* the reference/unlink code here is quite subtle. It
		 is needed because the rendering of the web-pages, and
		 in particular the esp/ejs backend, is semi-async.  So
		 we could well end up in the connection timeout code
		 while inside http_process_input(), but we must not
		 destroy the stack variables being used by that
		 rendering process when we handle the timeout. */
		if (!talloc_reference(web->task, web)) goto failed;
		http_process_input(web);
		talloc_unlink(web->task, web);
	}
	return;

failed:
	stream_terminate_connection(conn, "websrv_recv: failed");
}


/*
  called when a web connection becomes writable
*/
static void websrv_send(struct stream_connection *conn, uint16_t flags)
{
	struct websrv_context *web = talloc_get_type(conn->private, 
						     struct websrv_context);
	NTSTATUS status;
	size_t nsent;
	DATA_BLOB b;

	b = web->output.content;
	b.data += web->output.nsent;
	b.length -= web->output.nsent;

	status = socket_send(conn->socket, &b, &nsent);
	if (NT_STATUS_IS_ERR(status)) {
		stream_terminate_connection(web->conn, "socket_send: failed");
		return;
	}
	if (!NT_STATUS_IS_OK(status)) {
		return;
	}

	web->output.nsent += nsent;

	/* possibly read some more raw data from a file */
	if (web->output.content.length == web->output.nsent && 
	    web->output.fd != -1) {
		uint8_t buf[2048];
		ssize_t nread;

		data_blob_free(&web->output.content);
		web->output.nsent = 0;

		nread = read(web->output.fd, buf, sizeof(buf));
		if (nread == -1 && errno == EINTR) {
			return;
		}
		if (nread <= 0) {
			close(web->output.fd);
			web->output.fd = -1;
			nread = 0;
		}
		web->output.content = data_blob_talloc(web, buf, nread);
	}

	if (web->output.content.length == web->output.nsent && 
	    web->output.fd == -1) {
		stream_terminate_connection(web->conn, "websrv_send: finished sending");
	}
}

/*
  establish a new connection to the web server
*/
static void websrv_accept(struct stream_connection *conn)
{
	struct task_server *task = talloc_get_type(conn->private, struct task_server);
	struct esp_data *edata = talloc_get_type(task->private, struct esp_data);
	struct websrv_context *web;
	struct socket_context *tls_socket;

	web = talloc_zero(conn, struct websrv_context);
	if (web == NULL) goto failed;

	web->task = task;
	web->conn = conn;
	conn->private = web;
	web->output.fd = -1;
	talloc_set_destructor(web, websrv_destructor);

	event_add_timed(conn->event.ctx, web, 
			timeval_current_ofs(HTTP_TIMEOUT, 0),
			websrv_timeout, web);

	/* Overwrite the socket with a (possibly) TLS socket */
	tls_socket = tls_init_server(edata->tls_params, conn->socket, 
				     conn->event.fde, "GPHO");
	/* We might not have TLS, or it might not have initilised */
	if (tls_socket) {
		talloc_unlink(conn, conn->socket);
		talloc_steal(conn, tls_socket);
		conn->socket = tls_socket;
	} else {
		DEBUG(3, ("TLS not available for web_server connections\n"));
	}

	return;

failed:
	talloc_free(conn);
}


static const struct stream_server_ops web_stream_ops = {
	.name			= "web",
	.accept_connection	= websrv_accept,
	.recv_handler		= websrv_recv,
	.send_handler		= websrv_send,
};

/*
  startup the web server task
*/
static void websrv_task_init(struct task_server *task)
{
	NTSTATUS status;
	uint16_t port = lp_web_port(task->lp_ctx);
	const struct model_ops *model_ops;

	task_server_set_title(task, "task[websrv]");

	/* run the web server as a single process */
	model_ops = process_model_byname("single");
	if (!model_ops) goto failed;

	if (lp_interfaces(task->lp_ctx) && lp_bind_interfaces_only(task->lp_ctx)) {
		int num_interfaces;
		int i;
		struct interface *ifaces;

		load_interfaces(NULL, lp_interfaces(task->lp_ctx), &ifaces);

		num_interfaces = iface_count(ifaces);
		for(i = 0; i < num_interfaces; i++) {
			const char *address = iface_n_ip(ifaces, i);
			status = stream_setup_socket(task->event_ctx, 
						     task->lp_ctx, model_ops, 
						     &web_stream_ops, 
						     "ipv4", address, 
						     &port, lp_socket_options(task->lp_ctx), 
						     task);
			if (!NT_STATUS_IS_OK(status)) goto failed;
		}

		talloc_free(ifaces);
	} else {
		status = stream_setup_socket(task->event_ctx, task->lp_ctx,
					     model_ops, &web_stream_ops, 
					     "ipv4", lp_socket_address(task->lp_ctx), 
					     &port, lp_socket_options(task->lp_ctx), task);
		if (!NT_STATUS_IS_OK(status)) goto failed;
	}

	/* startup the esp processor - unfortunately we can't do this
	   per connection as that wouldn't allow for session variables */
	status = http_setup_esp(task);
	if (!NT_STATUS_IS_OK(status)) goto failed;

	return;

failed:
	task_server_terminate(task, "websrv_task_init: failed to startup web server task");
}


/*
  called on startup of the web server service It's job is to start
  listening on all configured sockets
*/
static NTSTATUS websrv_init(struct event_context *event_context, 
			    struct loadparm_context *lp_ctx,
			    const struct model_ops *model_ops)
{	
	return task_server_startup(event_context, lp_ctx, 
				   model_ops, websrv_task_init);
}

/* called at smbd startup - register ourselves as a server service */
NTSTATUS server_service_web_init(void)
{
	return register_server_service("web", websrv_init);
}