summaryrefslogtreecommitdiff
path: root/source4/web_server/http.c
blob: 46b3106518ef56e115fb25bd31c88890aeabb40d (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
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
/* 
   Unix SMB/CIFS implementation.

   http handling code

   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 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 "smbd/service_task.h"
#include "web_server/web_server.h"
#include "smbd/service_stream.h"
#include "lib/events/events.h"
#include "system/filesys.h"
#include "system/iconv.h"
#include "system/time.h"
#include "web_server/esp/esp.h"
#include "dlinklist.h"

#define SWAT_SESSION_KEY "_swat_session_"
#define HTTP_PREAUTH_URI "/scripting/preauth.esp"

/* state of the esp subsystem for a specific request */
struct esp_state {
	struct websrv_context *web;
	struct EspRequest *req;
	struct MprVar variables[ESP_OBJ_MAX];
	struct session_data *session;
};

/* destroy a esp session */
static int esp_destructor(void *ptr)
{
	struct esp_state *esp = talloc_get_type(ptr, struct esp_state);

	if (esp->req) {
		espDestroyRequest(esp->req);
	}
	return 0;
}

/*
  output the http headers
*/
static void http_output_headers(struct websrv_context *web)
{
	int i;
	char *s;
	DATA_BLOB b;
	uint32_t content_length = 0;
	const char *response_string = "Unknown Code";
	const struct {
		unsigned code;
		const char *response_string;
	} codes[] = {
		{ 200, "OK" },
		{ 301, "Moved" },
		{ 302, "Found" },
		{ 303, "Method" },
		{ 304, "Not Modified" },
		{ 400, "Bad request" },
		{ 401, "Unauthorized" },
		{ 403, "Forbidden" },
		{ 404, "Not Found" },
		{ 500, "Internal Server Error" },
		{ 501, "Not implemented" }
	};
	for (i=0;i<ARRAY_SIZE(codes);i++) {
		if (codes[i].code == web->output.response_code) {
			response_string = codes[i].response_string;
		}
	}

	if (web->output.headers == NULL) return;
	s = talloc_asprintf(web, "HTTP/1.0 %u %s\r\n", 
			    web->output.response_code, response_string);
	if (s == NULL) return;
	for (i=0;web->output.headers[i];i++) {
		s = talloc_asprintf_append(s, "%s\r\n", web->output.headers[i]);
	}

	/* work out the content length */
	content_length = web->output.content.length;
	if (web->output.fd != -1) {
		struct stat st;
		fstat(web->output.fd, &st);
		content_length += st.st_size;
	}
	s = talloc_asprintf_append(s, "Content-Length: %u\r\n\r\n", content_length);
	if (s == NULL) return;

	b = web->output.content;
	web->output.content.data = s;
	web->output.content.length = strlen(s);
	data_blob_append(web, &web->output.content, b.data, b.length);
	data_blob_free(&b);
}

/*
  return the local path for a URL
*/
static const char *http_local_path(struct websrv_context *web, const char *url)
{
	int i;
	char *path;

	/* check that the url is OK */
	if (url[0] != '/') return NULL;

	for (i=0;url[i];i++) {
		if ((!isalnum(url[i]) && !strchr("./_", url[i])) ||
		    (url[i] == '.' && strchr("/.", url[i+1]))) {
			return NULL;
		}
	}

	path = talloc_asprintf(web, "%s/%s", lp_swat_directory(), url+1);
	if (path == NULL) return NULL;

	if (directory_exist(path)) {
		path = talloc_asprintf_append(path, "/index.esp");
	}
	return path;
}

/*
  called when esp wants to read a file to support include() calls
*/
static int http_readFile(EspHandle handle, char **buf, int *len, const char *path)
{
	struct websrv_context *web = talloc_get_type(handle, struct websrv_context);
	int fd = -1;
	struct stat st;
	*buf = NULL;

	path = http_local_path(web, path);
	if (path == NULL) goto failed;

	fd = open(path, O_RDONLY);
	if (fd == -1 || fstat(fd, &st) != 0 || !S_ISREG(st.st_mode)) goto failed;

	*buf = talloc_size(handle, st.st_size+1);
	if (*buf == NULL) goto failed;

	if (read(fd, *buf, st.st_size) != st.st_size) goto failed;

	(*buf)[st.st_size] = 0;

	close(fd);
	*len = st.st_size;
	return 0;

failed:
	DEBUG(0,("Failed to read file %s - %s\n", path, strerror(errno)));
	if (fd != -1) close(fd);
	talloc_free(*buf);
	*buf = NULL;
	return -1;
}

/*
  called when esp wants to find the real path of a file
*/
static int http_mapToStorage(EspHandle handle, char *path, int len, const char *uri, int flags)
{
	if (uri == NULL || strlen(uri) >= len) return -1;
	strncpy(path, uri, len);
	return 0;
}

/*
  called when esp wants to output something
*/
static int http_writeBlock(EspHandle handle, char *buf, int size)
{
	struct websrv_context *web = talloc_get_type(handle, struct websrv_context);
	NTSTATUS status;
	status = data_blob_append(web, &web->output.content, buf, size);
	if (!NT_STATUS_IS_OK(status)) return -1;
	return size;
}


/*
  set a http header
*/
static void http_setHeader(EspHandle handle, const char *value, bool allowMultiple)
{
	struct websrv_context *web = talloc_get_type(handle, struct websrv_context);
	char *p = strchr(value, ':');

	if (p && !allowMultiple && web->output.headers) {
		int i;
		for (i=0;web->output.headers[i];i++) {
			if (strncmp(web->output.headers[i], value, (p+1)-value) == 0) {
				web->output.headers[i] = talloc_strdup(web, value);
				return;
			}
		}
	}

	web->output.headers = str_list_add(web->output.headers, value);
	talloc_steal(web, web->output.headers);
}

/*
  set a http response code
*/
static void http_setResponseCode(EspHandle handle, int code)
{
	struct websrv_context *web = talloc_get_type(handle, struct websrv_context);
	web->output.response_code = code;
}

/*
  redirect to another web page
 */
static void http_redirect(EspHandle handle, int code, char *url)
{
	struct websrv_context *web = talloc_get_type(handle, struct websrv_context);
	const char *host = web->input.host;
	
	/* form the full url, unless it already looks like a url */
	if (strchr(url, ':') == NULL) {
		if (host == NULL) {
			host = talloc_asprintf(web, "%s:%u",
					       socket_get_my_addr(web->conn->socket, web),
					       socket_get_my_port(web->conn->socket));
		}
		if (host == NULL) goto internal_error;
		if (url[0] != '/') {
			char *p = strrchr(web->input.url, '/');
			if (p == web->input.url) {
				url = talloc_asprintf(web, "http%s://%s/%s", 
						      web->tls_session?"s":"",
						      host, url);
			} else {
				int dirlen = p - web->input.url;
				url = talloc_asprintf(web, "http%s://%s%*.*s/%s",
						      web->tls_session?"s":"",
						      host, 
						      dirlen, dirlen, web->input.url,
						      url);
			}
			if (url == NULL) goto internal_error;
		}
	}

	http_setHeader(handle, talloc_asprintf(web, "Location: %s", url), 0);

	/* make sure we give a valid redirect code */
	if (code >= 300 && code < 400) {
		http_setResponseCode(handle, code);
	} else {
		http_setResponseCode(handle, 302);
	}
	return;

internal_error:
	http_error(web, 500, "Internal server error");
}


/*
  setup a cookie
*/
static void http_setCookie(EspHandle handle, const char *name, const char *value, 
			   int lifetime, const char *path, bool secure)
{
	struct websrv_context *web = talloc_get_type(handle, struct websrv_context);
	char *buf;
	
	if (lifetime > 0) {
		buf = talloc_asprintf(web, "Set-Cookie: %s=%s; path=%s; Expires=%s; %s",
				      name, value, path?path:"/", 
				      http_timestring(web, time(NULL)+lifetime),
				      secure?"secure":"");
	} else {
		buf = talloc_asprintf(web, "Set-Cookie: %s=%s; path=%s; %s",
				      name, value, path?path:"/", 
				      secure?"secure":"");
	}
	http_setHeader(handle, "Cache-control: no-cache=\"set-cookie\"", 0);
	http_setHeader(handle, buf, 0);
	talloc_free(buf);
}

/*
  return the session id
*/
static const char *http_getSessionId(EspHandle handle)
{
	struct websrv_context *web = talloc_get_type(handle, struct websrv_context);
	return web->session->id;
}

/*
  setup a session
*/
static void http_createSession(EspHandle handle, int timeout)
{
	struct websrv_context *web = talloc_get_type(handle, struct websrv_context);
	if (web->session) {
		web->session->lifetime = timeout;
		http_setCookie(web, SWAT_SESSION_KEY, web->session->id, 
			       web->session->lifetime, "/", 0);
	}
}

/*
  destroy a session
*/
static void http_destroySession(EspHandle handle)
{
	struct websrv_context *web = talloc_get_type(handle, struct websrv_context);
	talloc_free(web->session);
	web->session = NULL;
}


/*
  setup for a raw http level error
*/
void http_error(struct websrv_context *web, int code, const char *info)
{
	char *s;
	s = talloc_asprintf(web,"<HTML><HEAD><TITLE>Error %u</TITLE></HEAD><BODY><H1>Error %u</H1>%s<p></BODY></HTML>\r\n\r\n", 
			    code, code, info);
	if (s == NULL) {
		stream_terminate_connection(web->conn, "http_error: out of memory");
		return;
	}
	http_writeBlock(web, s, strlen(s));
	http_setResponseCode(web, code);
	http_output_headers(web);
	EVENT_FD_NOT_READABLE(web->conn->event.fde);
	EVENT_FD_WRITEABLE(web->conn->event.fde);
	web->output.output_pending = True;
}

/*
  map a unix error code to a http error
*/
void http_error_unix(struct websrv_context *web, const char *info)
{
	int code = 500;
	switch (errno) {
	case ENOENT:
	case EISDIR:
		code = 404;
		break;
	case EACCES:
		code = 403;
		break;
	}
	info = talloc_asprintf(web, "%s<p>%s<p>\n", info, strerror(errno));
	http_error(web, code, info);
}


/*
  a simple file request
*/
static void http_simple_request(struct websrv_context *web)
{
	const char *url = web->input.url;
	const char *path;
	struct stat st;

	path = http_local_path(web, url);
	if (path == NULL) goto invalid;

	/* looks ok */
	web->output.fd = open(path, O_RDONLY);
	if (web->output.fd == -1) {
		DEBUG(0,("Failed to read file %s - %s\n", path, strerror(errno)));
		http_error_unix(web, path);
		return;
	}

	if (fstat(web->output.fd, &st) != 0 || !S_ISREG(st.st_mode)) {
		close(web->output.fd);
		goto invalid;
	}

	return;

invalid:
	http_error(web, 400, "Malformed URL");
}

/*
  setup the standard ESP arrays
*/
static void http_setup_arrays(struct esp_state *esp)
{
	struct websrv_context *web = esp->web;
	struct esp_data *edata = talloc_get_type(web->task->private, struct esp_data);
	struct EspRequest *req = esp->req;
	char *p;

#define SETVAR(type, name, value) do { \
		const char *v = value; \
		if (v) espSetStringVar(req, type, name, v); \
} while (0)

	SETVAR(ESP_REQUEST_OBJ, "CONTENT_LENGTH", 
	       talloc_asprintf(esp, "%u", web->input.content_length));
	SETVAR(ESP_REQUEST_OBJ, "QUERY_STRING", web->input.query_string);
	SETVAR(ESP_REQUEST_OBJ, "REQUEST_METHOD", web->input.post_request?"POST":"GET");
	SETVAR(ESP_REQUEST_OBJ, "REQUEST_URI", web->input.url);
	p = strrchr(web->input.url, '/');
	SETVAR(ESP_REQUEST_OBJ, "SCRIPT_NAME", p+1);
	SETVAR(ESP_REQUEST_OBJ, "SCRIPT_FILENAME", web->input.url);
	p = socket_get_peer_name(web->conn->socket, esp);
	SETVAR(ESP_REQUEST_OBJ, "REMOTE_HOST", p);
	SETVAR(ESP_REQUEST_OBJ, "REMOTE_ADDR", p);
	SETVAR(ESP_REQUEST_OBJ, "REMOTE_USER", "");
	SETVAR(ESP_REQUEST_OBJ, "CONTENT_TYPE", web->input.content_type);
	if (web->session) {
		SETVAR(ESP_REQUEST_OBJ, "SESSION_ID", web->session->id);
	}

	SETVAR(ESP_HEADERS_OBJ, "HTT_REFERER", web->input.referer);
	SETVAR(ESP_HEADERS_OBJ, "HOST", web->input.host);
	SETVAR(ESP_HEADERS_OBJ, "ACCEPT_ENCODING", web->input.accept_encoding);
	SETVAR(ESP_HEADERS_OBJ, "ACCEPT_LANGUAGE", web->input.accept_language);
	SETVAR(ESP_HEADERS_OBJ, "ACCEPT_CHARSET", web->input.accept_charset);
	SETVAR(ESP_HEADERS_OBJ, "COOKIE", web->input.cookie);
	SETVAR(ESP_HEADERS_OBJ, "USER_AGENT", web->input.user_agent);

	SETVAR(ESP_SERVER_OBJ, "SERVER_ADDR", socket_get_my_addr(web->conn->socket, esp));
	SETVAR(ESP_SERVER_OBJ, "SERVER_NAME", socket_get_my_addr(web->conn->socket, esp));
	SETVAR(ESP_SERVER_OBJ, "SERVER_HOST", socket_get_my_addr(web->conn->socket, esp));
	SETVAR(ESP_SERVER_OBJ, "DOCUMENT_ROOT", lp_swat_directory());
	SETVAR(ESP_SERVER_OBJ, "SERVER_PORT", 
	       talloc_asprintf(esp, "%u", socket_get_my_port(web->conn->socket)));
	SETVAR(ESP_SERVER_OBJ, "SERVER_PROTOCOL", web->tls_session?"https":"http");
	SETVAR(ESP_SERVER_OBJ, "SERVER_SOFTWARE", "SWAT");
	SETVAR(ESP_SERVER_OBJ, "GATEWAY_INTERFACE", "CGI/1.1");
	SETVAR(ESP_SERVER_OBJ, "TLS_SUPPORT", edata->tls_data?"True":"False");
}

#if HAVE_SETJMP_H
/* the esp scripting lirary generates exceptions when
   it hits a major error. We need to catch these and
   report a internal server error via http
*/
#include <setjmp.h>
static jmp_buf ejs_exception_buf;
static const char *exception_reason;

void ejs_exception(const char *reason)
{
	exception_reason = reason;
	DEBUG(0,("%s", reason));
	longjmp(ejs_exception_buf, -1);
}
#else
void ejs_exception(const char *reason)
{
	DEBUG(0,("%s", reason));
	smb_panic(reason);
}
#endif

/*
  process a esp request
*/
static void esp_request(struct esp_state *esp, const char *url)
{
	struct websrv_context *web = esp->web;
	size_t size;
	int res;
	char *emsg = NULL, *buf;

	if (http_readFile(web, &buf, &size, url) != 0) {
		http_error_unix(web, url);
		return;
	}

#if HAVE_SETJMP_H
	if (setjmp(ejs_exception_buf) != 0) {
		http_error(web, 500, exception_reason);
		return;
	}
#endif
	res = espProcessRequest(esp->req, url, buf, &emsg);
	if (res != 0 && emsg) {
		http_writeBlock(web, emsg, strlen(emsg));
	}
	talloc_free(buf);
}


/*
  perform pre-authentication on every page is /scripting/preauth.esp
  exists.  If this script generates any non-whitepace output at all,
  then we don't run the requested URL.

  note that the preauth is run even for static pages such as images.
*/
static BOOL http_preauth(struct esp_state *esp)
{
	const char *path = http_local_path(esp->web, HTTP_PREAUTH_URI);
	int i;
	if (path == NULL) {
		http_error(esp->web, 500, "Internal server error");
		return False;
	}
	if (!file_exist(path)) {
		/* if the preath script is not installed then allow access */
		return True;
	}
	esp_request(esp, HTTP_PREAUTH_URI);
	for (i=0;i<esp->web->output.content.length;i++) {
		if (!isspace(esp->web->output.content.data[i])) {
			/* if the preauth has generated content, then force it to be
			   html, so that we can show the login page for failed
			   access to images */
			http_setHeader(esp->web, "Content-Type: text/html", 0);
			return False;
		}
	}
	data_blob_free(&esp->web->output.content);
	return True;
}


/* 
   handling of + and % escapes in http variables 
*/
static const char *http_unescape(TALLOC_CTX *mem_ctx, const char *p)
{
	char *s0 = talloc_strdup(mem_ctx, p);
	char *s = s0;
	if (s == NULL) return NULL;

	while (*s) {
		unsigned v;
		if (*s == '+') *s = ' ';
		if (*s == '%' && sscanf(s+1, "%02x", &v) == 1) {
			*s = (char)v;
			memmove(s+1, s+3, strlen(s+3)+1);
		}
		s++;
	}

	return s0;
}

/*
  set a form or GET variable
*/
static void esp_putvar(struct esp_state *esp, const char *var, const char *value)
{
	espSetStringVar(esp->req, ESP_FORM_OBJ, 
			http_unescape(esp, var),
			http_unescape(esp, value));
}


/*
  parse the variables in a POST style request
*/
static NTSTATUS http_parse_post(struct esp_state *esp)
{
	DATA_BLOB b = esp->web->input.partial;

	while (b.length) {
		char *p, *line;
		size_t len;

		p = memchr(b.data, '&', b.length);
		if (p == NULL) {
			len = b.length;
		} else {
			len = p - (char *)b.data;
		}
		line = talloc_strndup(esp, b.data, len);
		NT_STATUS_HAVE_NO_MEMORY(line);
				     
		p = strchr(line,'=');
		if (p) {
			*p = 0;
			esp_putvar(esp, line, p+1);
		}
		talloc_free(line);
		b.length -= len;
		b.data += len;
		if (b.length > 0) {
			b.length--;
			b.data++;
		}
	}

	return NT_STATUS_OK;
}

/*
  parse the variables in a GET style request
*/
static NTSTATUS http_parse_get(struct esp_state *esp)
{
	struct websrv_context *web = esp->web;
	char *p, *s, *tok;
	char *pp;

	p = strchr(web->input.url, '?');
	web->input.query_string = p+1;
	*p = 0;

	s = talloc_strdup(esp, esp->web->input.query_string);
	NT_STATUS_HAVE_NO_MEMORY(s);

	for (tok=strtok_r(s,"&;", &pp);tok;tok=strtok_r(NULL,"&;", &pp)) {
		p = strchr(tok,'=');
		if (p) {
			*p = 0;
			esp_putvar(esp, tok, p+1);
		}
	}
	return NT_STATUS_OK;
}

/*
  called when a session times out
*/
static void session_timeout(struct event_context *ev, struct timed_event *te, 
			    struct timeval t, void *private)
{
	struct session_data *s = talloc_get_type(private, struct session_data);
	talloc_free(s);
}

/*
  destroy a session
 */
static int session_destructor(void *ptr)
{
	struct session_data *s = talloc_get_type(ptr, struct session_data);
	DLIST_REMOVE(s->edata->sessions, s);
	return 0;
}

/*
  setup the session for this request
*/
static void http_setup_session(struct esp_state *esp)
{
	const char *session_key = SWAT_SESSION_KEY;
	char *p;
	const char *cookie = esp->web->input.cookie;
	const char *key = NULL;
	struct esp_data *edata = talloc_get_type(esp->web->task->private, struct esp_data);
	struct session_data *s;

	/* look for our session key */
	if (cookie && (p = strstr(cookie, session_key)) && 
	    p[strlen(session_key)] == '=') {
		p += strlen(session_key)+1;
		key = talloc_strndup(esp, p, strcspn(p, ";"));
	}

	if (key == NULL) {
		key = generate_random_str_list(esp, 64, "0123456789");
	}

	/* try to find this session in the existing session list */
	for (s=edata->sessions;s;s=s->next) {
		if (strcmp(key, s->id) == 0) break;
	}

	if (s == NULL) {
		/* create a new session */
		s = talloc_zero(edata, struct session_data);
		s->id = talloc_steal(s, key);
		s->data = NULL;
		s->te = NULL;
		s->edata = edata;
		s->lifetime = lp_parm_int(-1, "web", "sessiontimeout", 300);
		DLIST_ADD(edata->sessions, s);
		talloc_set_destructor(s, session_destructor);
	}

	http_setCookie(esp->web, session_key, key, s->lifetime, "/", 0);

	if (s->data) {
		mprCopyVar(&esp->variables[ESP_SESSION_OBJ], s->data, MPR_DEEP_COPY);
	}

	esp->web->session = s;
}


/* callbacks for esp processing */
static const struct Esp esp_control = {
	.maxScriptSize   = 60000,
	.writeBlock      = http_writeBlock,
	.setHeader       = http_setHeader,
	.redirect        = http_redirect,
	.setResponseCode = http_setResponseCode,
	.readFile        = http_readFile,
	.mapToStorage    = http_mapToStorage,
	.setCookie       = http_setCookie,
	.createSession   = http_createSession,
	.destroySession  = http_destroySession,
	.getSessionId    = http_getSessionId
};

/*
  process a complete http request
*/
void http_process_input(struct websrv_context *web)
{
	NTSTATUS status;
	struct esp_state *esp;
	struct esp_data *edata = talloc_get_type(web->task->private, struct esp_data);
	char *p;
	int i;
	const char *file_type = NULL;
	BOOL esp_enable = False;
	const struct {
		const char *extension;
		const char *mime_type;
		BOOL esp_enable;
	} mime_types[] = {
		{"gif",  "image/gif"},
		{"png",  "image/png"},
		{"jpg",  "image/jpeg"},
		{"txt",  "text/plain"},
		{"ico",  "image/x-icon"},
		{"css",  "text/css"},
		{"esp",  "text/html", True}
	};

	esp = talloc_zero(web, struct esp_state);
	if (esp == NULL) goto internal_error;

	esp->web = web;

	mprSetCtx(esp);

	if (espOpen(&esp_control) != 0) goto internal_error;

	for (i=0;i<ARRAY_SIZE(esp->variables);i++) {
		esp->variables[i] = mprCreateUndefinedVar();
	}
	esp->variables[ESP_HEADERS_OBJ]     = mprCreateObjVar("headers", ESP_HASH_SIZE);
	esp->variables[ESP_FORM_OBJ]        = mprCreateObjVar("form", ESP_HASH_SIZE);
	esp->variables[ESP_APPLICATION_OBJ] = mprCreateObjVar("application", ESP_HASH_SIZE);
	esp->variables[ESP_COOKIES_OBJ]     = mprCreateObjVar("cookies", ESP_HASH_SIZE);
	esp->variables[ESP_FILES_OBJ]       = mprCreateObjVar("files", ESP_HASH_SIZE);
	esp->variables[ESP_REQUEST_OBJ]     = mprCreateObjVar("request", ESP_HASH_SIZE);
	esp->variables[ESP_SERVER_OBJ]      = mprCreateObjVar("server", ESP_HASH_SIZE);
	esp->variables[ESP_SESSION_OBJ]     = mprCreateObjVar("session", ESP_HASH_SIZE);

	if (edata->application_data) {
		mprCopyVar(&esp->variables[ESP_APPLICATION_OBJ], 
			   edata->application_data, MPR_DEEP_COPY);
	}

	http_setup_session(esp);

	talloc_set_destructor(esp, esp_destructor);

	smb_setup_ejs_functions();
	http_setup_ejs_functions();

	esp->req = espCreateRequest(web, web->input.url, esp->variables);
	if (esp->req == NULL) goto internal_error;

	if (web->input.url == NULL) {
		http_error(web, 400, "You must specify a GET or POST request");
		return;
	}
	
	/* parse any form or get variables */
	if (web->input.post_request) {
		status = http_parse_post(esp);
		if (!NT_STATUS_IS_OK(status)) {
			http_error(web, 400, "Malformed POST data");
			return;
		}
	} else if (strchr(web->input.url, '?')) {
		status = http_parse_get(esp);
		if (!NT_STATUS_IS_OK(status)) {
			http_error(web, 400, "Malformed GET data");
			return;
		}
	}

	/* work out the mime type */
	p = strrchr(web->input.url, '.');
	if (p == NULL) {
		esp_enable = True;
	}
	for (i=0;p && i<ARRAY_SIZE(mime_types);i++) {
		if (strcmp(mime_types[i].extension, p+1) == 0) {
			file_type = mime_types[i].mime_type;
			esp_enable = mime_types[i].esp_enable;
		}
	}
	if (file_type == NULL) {
		file_type = "text/html";
	}

	/* setup basic headers */
	http_setResponseCode(web, 200);
	http_setHeader(web, talloc_asprintf(esp, "Date: %s", 
					    http_timestring(esp, time(NULL))), 0);
	http_setHeader(web, "Server: Samba", 0);
	http_setHeader(web, "Connection: close", 0);
	http_setHeader(web, talloc_asprintf(esp, "Content-Type: %s", file_type), 0);

	http_setup_arrays(esp);

	/* possibly do pre-authentication */
	if (http_preauth(esp)) {
		if (esp_enable) {
			esp_request(esp, web->input.url);
		} else {
			http_simple_request(web);
		}
	}

	if (!web->output.output_pending) {
		http_output_headers(web);
		EVENT_FD_WRITEABLE(web->conn->event.fde);
		web->output.output_pending = True;
	}

	/* copy any application data to long term storage in edata */
	talloc_free(edata->application_data);
	edata->application_data = talloc_zero(edata, struct MprVar);
	mprSetCtx(edata->application_data);
	mprCopyVar(edata->application_data, &esp->variables[ESP_APPLICATION_OBJ], MPR_DEEP_COPY);

	/* copy any session data */
	if (web->session) {
		talloc_free(web->session->data);
		web->session->data = talloc_zero(web->session, struct MprVar);
		mprSetCtx(web->session->data);
		if (esp->variables[ESP_SESSION_OBJ].properties == NULL ||
		    esp->variables[ESP_SESSION_OBJ].properties[0].numItems == 0) {
			talloc_free(web->session);
			web->session = NULL;
		} else {
			mprCopyVar(web->session->data, &esp->variables[ESP_SESSION_OBJ], 
				   MPR_DEEP_COPY);
			/* setup the timeout for the session data */
			talloc_free(web->session->te);
			web->session->te = event_add_timed(web->conn->event.ctx, web->session, 
							   timeval_current_ofs(web->session->lifetime, 0), 
							   session_timeout, web->session);
		}
	}

	talloc_free(esp);
	return;
	
internal_error:
	talloc_free(esp);
	http_error(web, 500, "Internal server error");
}


/*
  parse one line of header input
*/
NTSTATUS http_parse_header(struct websrv_context *web, const char *line)
{
	if (line[0] == 0) {
		web->input.end_of_headers = True;
	} else if (strncasecmp(line,"GET ", 4)==0) {
		web->input.url = talloc_strndup(web, &line[4], strcspn(&line[4], " \t"));
	} else if (strncasecmp(line,"POST ", 5)==0) {
		web->input.post_request = True;
		web->input.url = talloc_strndup(web, &line[5], strcspn(&line[5], " \t"));
	} else if (strchr(line, ':') == NULL) {
		http_error(web, 400, "This server only accepts GET and POST requests");
		return NT_STATUS_INVALID_PARAMETER;
	} else if (strncasecmp(line,"Content-Length: ", 16)==0) {
		web->input.content_length = strtoul(&line[16], NULL, 10);
	} else {
#define PULL_HEADER(v, s) do { \
	if (strncmp(line, s, strlen(s)) == 0) { \
		web->input.v = talloc_strdup(web, &line[strlen(s)]); \
		return NT_STATUS_OK; \
	} \
} while (0)
		PULL_HEADER(content_type, "Content-Type: ");
		PULL_HEADER(user_agent, "User-Agent: ");
		PULL_HEADER(referer, "Referer: ");
		PULL_HEADER(host, "Host: ");
		PULL_HEADER(accept_encoding, "Accept-Encoding: ");
		PULL_HEADER(accept_language, "Accept-Language: ");
		PULL_HEADER(accept_charset, "Accept-Charset: ");
		PULL_HEADER(cookie, "Cookie: ");
	}

	/* ignore all other headers for now */
	return NT_STATUS_OK;
}


/*
  setup the esp processor - called at task initialisation
*/
NTSTATUS http_setup_esp(struct task_server *task)
{
	struct esp_data *edata;

	edata = talloc_zero(task, struct esp_data);
	NT_STATUS_HAVE_NO_MEMORY(edata);

	task->private = edata;

	return NT_STATUS_OK;
}