double check that parsing a list consumes all bytes
[strongswan.git] / src / charon / encoding / parser.c
1 /*
2 * Copyright (C) 2005-2009 Martin Willi
3 * Copyright (C) 2005 Jan Hutter
4 * Hochschule fuer Technik Rapperswil
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * for more details.
15 */
16
17 #include <stdlib.h>
18 #include <arpa/inet.h>
19 #include <string.h>
20
21 #include "parser.h"
22
23 #include <library.h>
24 #include <daemon.h>
25 #include <utils/linked_list.h>
26 #include <encoding/payloads/encodings.h>
27 #include <encoding/payloads/payload.h>
28 #include <encoding/payloads/sa_payload.h>
29 #include <encoding/payloads/proposal_substructure.h>
30 #include <encoding/payloads/transform_substructure.h>
31 #include <encoding/payloads/transform_attribute.h>
32 #include <encoding/payloads/ke_payload.h>
33 #include <encoding/payloads/nonce_payload.h>
34 #include <encoding/payloads/id_payload.h>
35 #include <encoding/payloads/notify_payload.h>
36 #include <encoding/payloads/encryption_payload.h>
37 #include <encoding/payloads/auth_payload.h>
38 #include <encoding/payloads/cert_payload.h>
39 #include <encoding/payloads/certreq_payload.h>
40 #include <encoding/payloads/ts_payload.h>
41 #include <encoding/payloads/delete_payload.h>
42 #include <encoding/payloads/vendor_id_payload.h>
43 #include <encoding/payloads/cp_payload.h>
44 #include <encoding/payloads/configuration_attribute.h>
45 #include <encoding/payloads/eap_payload.h>
46 #include <encoding/payloads/unknown_payload.h>
47
48
49 typedef struct private_parser_t private_parser_t;
50
51 /**
52 * Private data stored in a context.
53 *
54 * Contains pointers and counters to store current state.
55 */
56 struct private_parser_t {
57 /**
58 * Public members, see parser_t.
59 */
60 parser_t public;
61
62 /**
63 * Current bit for reading in input data.
64 */
65 u_int8_t bit_pos;
66
67 /**
68 * Current byte for reading in input data.
69 */
70 u_int8_t *byte_pos;
71
72 /**
73 * Input data to parse.
74 */
75 u_int8_t *input;
76
77 /**
78 * Roof of input, used for length-checking.
79 */
80 u_int8_t *input_roof;
81
82 /**
83 * Set of encoding rules for this parsing session.
84 */
85 encoding_rule_t *rules;
86 };
87
88 /**
89 * Forward declaration
90 */
91 static status_t parse_payload(private_parser_t *this,
92 payload_type_t payload_type, payload_t **payload);
93
94 /**
95 * Log invalid length error
96 */
97 static bool short_input(private_parser_t *this, int number)
98 {
99 DBG1(DBG_ENC, " not enough input to parse rule %d %N",
100 number, encoding_type_names, this->rules[number].type);
101 return FALSE;
102 }
103
104 /**
105 * Log unaligned rules
106 */
107 static bool bad_bitpos(private_parser_t *this, int number)
108 {
109 DBG1(DBG_ENC, " found rule %d %N on bitpos %d",
110 number, encoding_type_names, this->rules[number].type, this->bit_pos);
111 return FALSE;
112 }
113
114 /**
115 * Parse a 4-Bit unsigned integer from the current parsing position.
116 */
117 static bool parse_uint4(private_parser_t *this, int rule_number,
118 u_int8_t *output_pos)
119 {
120 if (this->byte_pos + sizeof(u_int8_t) > this->input_roof)
121 {
122 return short_input(this, rule_number);
123 }
124 switch (this->bit_pos)
125 {
126 case 0:
127 if (output_pos)
128 {
129 *output_pos = *(this->byte_pos) >> 4;
130 }
131 this->bit_pos = 4;
132 break;
133 case 4:
134 if (output_pos)
135 {
136 *output_pos = *(this->byte_pos) & 0x0F;
137 }
138 this->bit_pos = 0;
139 this->byte_pos++;
140 break;
141 default:
142 return bad_bitpos(this, rule_number);
143 }
144 if (output_pos)
145 {
146 DBG3(DBG_ENC, " => %d", *output_pos);
147 }
148 return TRUE;
149 }
150
151 /**
152 * Parse a 8-Bit unsigned integer from the current parsing position.
153 */
154 static bool parse_uint8(private_parser_t *this, int rule_number,
155 u_int8_t *output_pos)
156 {
157 if (this->byte_pos + sizeof(u_int8_t) > this->input_roof)
158 {
159 return short_input(this, rule_number);
160 }
161 if (this->bit_pos)
162 {
163 return bad_bitpos(this, rule_number);
164 }
165 if (output_pos)
166 {
167 *output_pos = *(this->byte_pos);
168 DBG3(DBG_ENC, " => %d", *output_pos);
169 }
170 this->byte_pos++;
171 return TRUE;
172 }
173
174 /**
175 * Parse a 15-Bit unsigned integer from the current parsing position.
176 */
177 static bool parse_uint15(private_parser_t *this, int rule_number,
178 u_int16_t *output_pos)
179 {
180 if (this->byte_pos + sizeof(u_int16_t) > this->input_roof)
181 {
182 return short_input(this, rule_number);
183 }
184 if (this->bit_pos != 1)
185 {
186 return bad_bitpos(this, rule_number);
187 }
188 if (output_pos)
189 {
190 memcpy(output_pos, this->byte_pos, sizeof(u_int16_t));
191 *output_pos = ntohs(*output_pos) & ~0x8000;
192 DBG3(DBG_ENC, " => %d", *output_pos);
193 }
194 this->byte_pos += sizeof(u_int16_t);
195 this->bit_pos = 0;
196 return TRUE;
197 }
198
199 /**
200 * Parse a 16-Bit unsigned integer from the current parsing position.
201 */
202 static bool parse_uint16(private_parser_t *this, int rule_number,
203 u_int16_t *output_pos)
204 {
205 if (this->byte_pos + sizeof(u_int16_t) > this->input_roof)
206 {
207 return short_input(this, rule_number);
208 }
209 if (this->bit_pos)
210 {
211 return bad_bitpos(this, rule_number);
212 }
213 if (output_pos)
214 {
215 memcpy(output_pos, this->byte_pos, sizeof(u_int16_t));
216 *output_pos = ntohs(*output_pos);
217 DBG3(DBG_ENC, " => %d", *output_pos);
218 }
219 this->byte_pos += sizeof(u_int16_t);
220 return TRUE;
221 }
222 /**
223 * Parse a 32-Bit unsigned integer from the current parsing position.
224 */
225 static bool parse_uint32(private_parser_t *this, int rule_number,
226 u_int32_t *output_pos)
227 {
228 if (this->byte_pos + sizeof(u_int32_t) > this->input_roof)
229 {
230 return short_input(this, rule_number);
231 }
232 if (this->bit_pos)
233 {
234 return bad_bitpos(this, rule_number);
235 }
236 if (output_pos)
237 {
238 memcpy(output_pos, this->byte_pos, sizeof(u_int32_t));
239 *output_pos = ntohl(*output_pos);
240 DBG3(DBG_ENC, " => %d", *output_pos);
241 }
242 this->byte_pos += sizeof(u_int32_t);
243 return TRUE;
244 }
245
246 /**
247 * Parse a given amount of bytes and writes them to a specific location
248 */
249 static bool parse_bytes(private_parser_t *this, int rule_number,
250 u_int8_t *output_pos, int bytes)
251 {
252 if (this->byte_pos + bytes > this->input_roof)
253 {
254 return short_input(this, rule_number);
255 }
256 if (this->bit_pos)
257 {
258 return bad_bitpos(this, rule_number);
259 }
260 if (output_pos)
261 {
262 memcpy(output_pos, this->byte_pos, bytes);
263 DBG3(DBG_ENC, " => %b", output_pos, bytes);
264 }
265 this->byte_pos += bytes;
266 return TRUE;
267 }
268
269 /**
270 * Parse a single Bit from the current parsing position
271 */
272 static bool parse_bit(private_parser_t *this, int rule_number,
273 bool *output_pos)
274 {
275 if (this->byte_pos + sizeof(u_int8_t) > this->input_roof)
276 {
277 return short_input(this, rule_number);
278 }
279 if (output_pos)
280 {
281 u_int8_t mask;
282 mask = 0x01 << (7 - this->bit_pos);
283 *output_pos = *this->byte_pos & mask;
284
285 if (*output_pos)
286 { /* set to a "clean", comparable true */
287 *output_pos = TRUE;
288 }
289 DBG3(DBG_ENC, " => %d", *output_pos);
290 }
291 this->bit_pos = (this->bit_pos + 1) % 8;
292 if (this->bit_pos == 0)
293 {
294 this->byte_pos++;
295 }
296 return TRUE;
297 }
298
299 /**
300 * Parse substructures in a list.
301 */
302 static bool parse_list(private_parser_t *this, int rule_number,
303 linked_list_t **output_pos, payload_type_t payload_type, int length)
304 {
305 linked_list_t *list = *output_pos;
306
307 if (length < 0)
308 {
309 return short_input(this, rule_number);
310 }
311 if (this->bit_pos)
312 {
313 return bad_bitpos(this, rule_number);
314 }
315 while (length > 0)
316 {
317 u_int8_t *pos_before = this->byte_pos;
318 payload_t *payload;
319
320 DBG2(DBG_ENC, " %d bytes left, parsing recursively %N",
321 length, payload_type_names, payload_type);
322
323 if (parse_payload(this, payload_type, &payload) != SUCCESS)
324 {
325 DBG1(DBG_ENC, " parsing of a %N substructure failed",
326 payload_type_names, payload_type);
327 return FALSE;
328 }
329 list->insert_last(list, payload);
330 length -= this->byte_pos - pos_before;
331 }
332 if (length != 0)
333 { /* must yield exactly to zero */
334 DBG1(DBG_ENC, " length of %N substructure list invalid",
335 payload_type_names, payload_type);
336 return FALSE;
337 }
338 *output_pos = list;
339 return TRUE;
340 }
341
342 /**
343 * Parse data from current parsing position in a chunk.
344 */
345 static bool parse_chunk(private_parser_t *this, int rule_number,
346 chunk_t *output_pos, int length)
347 {
348 if (this->byte_pos + length > this->input_roof)
349 {
350 return short_input(this, rule_number);
351 }
352 if (this->bit_pos)
353 {
354 return bad_bitpos(this, rule_number);
355 }
356 if (output_pos)
357 {
358 *output_pos = chunk_alloc(length);
359 memcpy(output_pos->ptr, this->byte_pos, length);
360 DBG3(DBG_ENC, " => %b", output_pos->ptr, length);
361 }
362 this->byte_pos += length;
363 return TRUE;
364 }
365
366 /**
367 * Implementation of parser_t.parse_payload.
368 */
369 static status_t parse_payload(private_parser_t *this,
370 payload_type_t payload_type, payload_t **payload)
371 {
372 payload_t *pld;
373 void *output;
374 int rule_count, payload_length = 0, spi_size = 0, attribute_length = 0;
375 u_int16_t ts_type = 0;
376 bool attribute_format = FALSE;
377 int rule_number;
378 encoding_rule_t *rule;
379
380 /* create instance of the payload to parse */
381 pld = payload_create(payload_type);
382
383 DBG2(DBG_ENC, "parsing %N payload, %d bytes left",
384 payload_type_names, payload_type, this->input_roof - this->byte_pos);
385
386 DBG3(DBG_ENC, "parsing payload from %b",
387 this->byte_pos, this->input_roof - this->byte_pos);
388
389 if (pld->get_type(pld) == UNKNOWN_PAYLOAD)
390 {
391 DBG1(DBG_ENC, " payload type %d is unknown, handling as %N",
392 payload_type, payload_type_names, UNKNOWN_PAYLOAD);
393 }
394
395 /* base pointer for output, avoids casting in every rule */
396 output = pld;
397
398 /* parse the payload with its own rulse */
399 pld->get_encoding_rules(pld, &(this->rules), &rule_count);
400 for (rule_number = 0; rule_number < rule_count; rule_number++)
401 {
402 rule = &(this->rules[rule_number]);
403 DBG2(DBG_ENC, " parsing rule %d %N",
404 rule_number, encoding_type_names, rule->type);
405 switch (rule->type)
406 {
407 case U_INT_4:
408 {
409 if (!parse_uint4(this, rule_number, output + rule->offset))
410 {
411 pld->destroy(pld);
412 return PARSE_ERROR;
413 }
414 break;
415 }
416 case U_INT_8:
417 {
418 if (!parse_uint8(this, rule_number, output + rule->offset))
419 {
420 pld->destroy(pld);
421 return PARSE_ERROR;
422 }
423 break;
424 }
425 case U_INT_16:
426 {
427 if (!parse_uint16(this, rule_number, output + rule->offset))
428 {
429 pld->destroy(pld);
430 return PARSE_ERROR;
431 }
432 break;
433 }
434 case U_INT_32:
435 {
436 if (!parse_uint32(this, rule_number, output + rule->offset))
437 {
438 pld->destroy(pld);
439 return PARSE_ERROR;
440 }
441 break;
442 }
443 case IKE_SPI:
444 {
445 if (!parse_bytes(this, rule_number, output + rule->offset, 8))
446 {
447 pld->destroy(pld);
448 return PARSE_ERROR;
449 }
450 break;
451 }
452 case RESERVED_BIT:
453 {
454 if (!parse_bit(this, rule_number, NULL))
455 {
456 pld->destroy(pld);
457 return PARSE_ERROR;
458 }
459 break;
460 }
461 case RESERVED_BYTE:
462 {
463 if (!parse_uint8(this, rule_number, NULL))
464 {
465 pld->destroy(pld);
466 return PARSE_ERROR;
467 }
468 break;
469 }
470 case FLAG:
471 {
472 if (!parse_bit(this, rule_number, output + rule->offset))
473 {
474 pld->destroy(pld);
475 return PARSE_ERROR;
476 }
477 break;
478 }
479 case PAYLOAD_LENGTH:
480 {
481 if (!parse_uint16(this, rule_number, output + rule->offset))
482 {
483 pld->destroy(pld);
484 return PARSE_ERROR;
485 }
486 /* parsed u_int16 should be aligned */
487 payload_length = *(u_int16_t*)(output + rule->offset);
488 if (payload_length < UNKNOWN_PAYLOAD_HEADER_LENGTH)
489 {
490 pld->destroy(pld);
491 return PARSE_ERROR;
492 }
493 break;
494 }
495 case HEADER_LENGTH:
496 {
497 if (!parse_uint32(this, rule_number, output + rule->offset))
498 {
499 pld->destroy(pld);
500 return PARSE_ERROR;
501 }
502 break;
503 }
504 case SPI_SIZE:
505 {
506 if (!parse_uint8(this, rule_number, output + rule->offset))
507 {
508 pld->destroy(pld);
509 return PARSE_ERROR;
510 }
511 spi_size = *(u_int8_t*)(output + rule->offset);
512 break;
513 }
514 case SPI:
515 {
516 if (!parse_chunk(this, rule_number, output + rule->offset,
517 spi_size))
518 {
519 pld->destroy(pld);
520 return PARSE_ERROR;
521 }
522 break;
523 }
524 case PROPOSALS:
525 {
526 if (payload_length < SA_PAYLOAD_HEADER_LENGTH ||
527 !parse_list(this, rule_number, output + rule->offset,
528 PROPOSAL_SUBSTRUCTURE,
529 payload_length - SA_PAYLOAD_HEADER_LENGTH))
530 {
531 pld->destroy(pld);
532 return PARSE_ERROR;
533 }
534 break;
535 }
536 case TRANSFORMS:
537 {
538 if (payload_length <
539 spi_size + PROPOSAL_SUBSTRUCTURE_HEADER_LENGTH ||
540 !parse_list(this, rule_number, output + rule->offset,
541 TRANSFORM_SUBSTRUCTURE, payload_length - spi_size -
542 PROPOSAL_SUBSTRUCTURE_HEADER_LENGTH))
543 {
544 pld->destroy(pld);
545 return PARSE_ERROR;
546 }
547 break;
548 }
549 case TRANSFORM_ATTRIBUTES:
550 {
551 if (payload_length < TRANSFORM_SUBSTRUCTURE_HEADER_LENGTH ||
552 !parse_list(this, rule_number, output + rule->offset,
553 TRANSFORM_ATTRIBUTE,
554 payload_length - TRANSFORM_SUBSTRUCTURE_HEADER_LENGTH))
555 {
556 pld->destroy(pld);
557 return PARSE_ERROR;
558 }
559 break;
560 }
561 case CONFIGURATION_ATTRIBUTES:
562 {
563 if (payload_length < CP_PAYLOAD_HEADER_LENGTH ||
564 !parse_list(this, rule_number, output + rule->offset,
565 CONFIGURATION_ATTRIBUTE,
566 payload_length - CP_PAYLOAD_HEADER_LENGTH))
567 {
568 pld->destroy(pld);
569 return PARSE_ERROR;
570 }
571 break;
572 }
573 case ATTRIBUTE_FORMAT:
574 {
575 if (!parse_bit(this, rule_number, output + rule->offset))
576 {
577 pld->destroy(pld);
578 return PARSE_ERROR;
579 }
580 attribute_format = *(bool*)(output + rule->offset);
581 break;
582 }
583 case ATTRIBUTE_TYPE:
584 {
585 if (!parse_uint15(this, rule_number, output + rule->offset))
586 {
587 pld->destroy(pld);
588 return PARSE_ERROR;
589 }
590 break;
591 }
592 case CONFIGURATION_ATTRIBUTE_LENGTH:
593 {
594 if (!parse_uint16(this, rule_number, output + rule->offset))
595 {
596 pld->destroy(pld);
597 return PARSE_ERROR;
598 }
599 attribute_length = *(u_int16_t*)(output + rule->offset);
600 break;
601 }
602 case ATTRIBUTE_LENGTH_OR_VALUE:
603 {
604 if (!parse_uint16(this, rule_number, output + rule->offset))
605 {
606 pld->destroy(pld);
607 return PARSE_ERROR;
608 }
609 attribute_length = *(u_int16_t*)(output + rule->offset);
610 break;
611 }
612 case ATTRIBUTE_VALUE:
613 {
614 if (attribute_format == FALSE &&
615 !parse_chunk(this, rule_number, output + rule->offset,
616 attribute_length))
617 {
618 pld->destroy(pld);
619 return PARSE_ERROR;
620 }
621 break;
622 }
623 case NONCE_DATA:
624 {
625 if (payload_length < NONCE_PAYLOAD_HEADER_LENGTH ||
626 !parse_chunk(this, rule_number, output + rule->offset,
627 payload_length - NONCE_PAYLOAD_HEADER_LENGTH))
628 {
629 pld->destroy(pld);
630 return PARSE_ERROR;
631 }
632 break;
633 }
634 case ID_DATA:
635 {
636 if (payload_length < ID_PAYLOAD_HEADER_LENGTH ||
637 !parse_chunk(this, rule_number, output + rule->offset,
638 payload_length - ID_PAYLOAD_HEADER_LENGTH))
639 {
640 pld->destroy(pld);
641 return PARSE_ERROR;
642 }
643 break;
644 }
645 case AUTH_DATA:
646 {
647 if (payload_length < AUTH_PAYLOAD_HEADER_LENGTH ||
648 !parse_chunk(this, rule_number, output + rule->offset,
649 payload_length - AUTH_PAYLOAD_HEADER_LENGTH))
650 {
651 pld->destroy(pld);
652 return PARSE_ERROR;
653 }
654 break;
655 }
656 case CERT_DATA:
657 {
658 if (payload_length < CERT_PAYLOAD_HEADER_LENGTH ||
659 !parse_chunk(this, rule_number, output + rule->offset,
660 payload_length - CERT_PAYLOAD_HEADER_LENGTH))
661 {
662 pld->destroy(pld);
663 return PARSE_ERROR;
664 }
665 break;
666 }
667 case CERTREQ_DATA:
668 {
669 if (payload_length < CERTREQ_PAYLOAD_HEADER_LENGTH ||
670 !parse_chunk(this, rule_number, output + rule->offset,
671 payload_length - CERTREQ_PAYLOAD_HEADER_LENGTH))
672 {
673 pld->destroy(pld);
674 return PARSE_ERROR;
675 }
676 break;
677 }
678 case EAP_DATA:
679 {
680 if (payload_length < EAP_PAYLOAD_HEADER_LENGTH ||
681 !parse_chunk(this, rule_number, output + rule->offset,
682 payload_length - EAP_PAYLOAD_HEADER_LENGTH))
683 {
684 pld->destroy(pld);
685 return PARSE_ERROR;
686 }
687 break;
688 }
689 case SPIS:
690 {
691 if (payload_length < DELETE_PAYLOAD_HEADER_LENGTH ||
692 !parse_chunk(this, rule_number, output + rule->offset,
693 payload_length - DELETE_PAYLOAD_HEADER_LENGTH))
694 {
695 pld->destroy(pld);
696 return PARSE_ERROR;
697 }
698 break;
699 }
700 case VID_DATA:
701 {
702 if (payload_length < VENDOR_ID_PAYLOAD_HEADER_LENGTH ||
703 !parse_chunk(this, rule_number, output + rule->offset,
704 payload_length - VENDOR_ID_PAYLOAD_HEADER_LENGTH))
705 {
706 pld->destroy(pld);
707 return PARSE_ERROR;
708 }
709 break;
710 }
711 case CONFIGURATION_ATTRIBUTE_VALUE:
712 {
713 if (!parse_chunk(this, rule_number, output + rule->offset,
714 attribute_length))
715 {
716 pld->destroy(pld);
717 return PARSE_ERROR;
718 }
719 break;
720 }
721 case KEY_EXCHANGE_DATA:
722 {
723 if (payload_length < KE_PAYLOAD_HEADER_LENGTH ||
724 !parse_chunk(this, rule_number, output + rule->offset,
725 payload_length - KE_PAYLOAD_HEADER_LENGTH))
726 {
727 pld->destroy(pld);
728 return PARSE_ERROR;
729 }
730 break;
731 }
732 case NOTIFICATION_DATA:
733 {
734 if (payload_length < NOTIFY_PAYLOAD_HEADER_LENGTH + spi_size ||
735 !parse_chunk(this, rule_number, output + rule->offset,
736 payload_length - NOTIFY_PAYLOAD_HEADER_LENGTH - spi_size))
737 {
738 pld->destroy(pld);
739 return PARSE_ERROR;
740 }
741 break;
742 }
743 case ENCRYPTED_DATA:
744 {
745 if (payload_length < ENCRYPTION_PAYLOAD_HEADER_LENGTH ||
746 !parse_chunk(this, rule_number, output + rule->offset,
747 payload_length - ENCRYPTION_PAYLOAD_HEADER_LENGTH))
748 {
749 pld->destroy(pld);
750 return PARSE_ERROR;
751 }
752 break;
753 }
754 case TS_TYPE:
755 {
756 if (!parse_uint8(this, rule_number, output + rule->offset))
757 {
758 pld->destroy(pld);
759 return PARSE_ERROR;
760 }
761 ts_type = *(u_int8_t*)(output + rule->offset);
762 break;
763 }
764 case ADDRESS:
765 {
766 int address_length = (ts_type == TS_IPV4_ADDR_RANGE) ? 4 : 16;
767
768 if (!parse_chunk(this, rule_number, output + rule->offset,
769 address_length))
770 {
771 pld->destroy(pld);
772 return PARSE_ERROR;
773 }
774 break;
775 }
776 case TRAFFIC_SELECTORS:
777 {
778 if (payload_length < TS_PAYLOAD_HEADER_LENGTH ||
779 !parse_list(this, rule_number, output + rule->offset,
780 TRAFFIC_SELECTOR_SUBSTRUCTURE,
781 payload_length - TS_PAYLOAD_HEADER_LENGTH))
782 {
783 pld->destroy(pld);
784 return PARSE_ERROR;
785 }
786 break;
787 }
788 case UNKNOWN_DATA:
789 {
790 if (payload_length < UNKNOWN_PAYLOAD_HEADER_LENGTH ||
791 !parse_chunk(this, rule_number, output + rule->offset,
792 payload_length - UNKNOWN_PAYLOAD_HEADER_LENGTH))
793 {
794 pld->destroy(pld);
795 return PARSE_ERROR;
796 }
797 break;
798 }
799 default:
800 {
801 DBG1(DBG_ENC, " no rule to parse rule %d %N",
802 rule_number, encoding_type_names, rule->type);
803 pld->destroy(pld);
804 return PARSE_ERROR;
805 }
806 }
807 /* process next rulue */
808 rule++;
809 }
810
811 *payload = pld;
812 DBG2(DBG_ENC, "parsing %N payload finished",
813 payload_type_names, payload_type);
814 return SUCCESS;
815 }
816
817 /**
818 * Implementation of parser_t.get_remaining_byte_count.
819 */
820 static int get_remaining_byte_count (private_parser_t *this)
821 {
822 return this->input_roof - this->byte_pos;
823 }
824
825 /**
826 * Implementation of parser_t.reset_context.
827 */
828 static void reset_context (private_parser_t *this)
829 {
830 this->byte_pos = this->input;
831 this->bit_pos = 0;
832 }
833
834 /**
835 * Implementation of parser_t.destroy.
836 */
837 static void destroy(private_parser_t *this)
838 {
839 free(this);
840 }
841
842 /*
843 * Described in header.
844 */
845 parser_t *parser_create(chunk_t data)
846 {
847 private_parser_t *this = malloc_thing(private_parser_t);
848
849 this->public.parse_payload = (status_t(*)(parser_t*,payload_type_t,payload_t**))parse_payload;
850 this->public.reset_context = (void(*)(parser_t*)) reset_context;
851 this->public.get_remaining_byte_count = (int (*) (parser_t *))get_remaining_byte_count;
852 this->public.destroy = (void(*)(parser_t*)) destroy;
853
854 this->input = data.ptr;
855 this->byte_pos = data.ptr;
856 this->bit_pos = 0;
857 this->input_roof = data.ptr + data.len;
858
859 return &this->public;
860 }
861