ReactOS 0.4.15-dev-7674-gc0b4db1
asn1_dec.c
Go to the documentation of this file.
1
8/*
9 * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or without modification,
13 * are permitted provided that the following conditions are met:
14 *
15 * 1. Redistributions of source code must retain the above copyright notice,
16 * this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright notice,
18 * this list of conditions and the following disclaimer in the documentation
19 * and/or other materials provided with the distribution.
20 * 3. The name of the author may not be used to endorse or promote products
21 * derived from this software without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
24 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
26 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
27 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
28 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
31 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
32 * OF SUCH DAMAGE.
33 *
34 * Author: Christiaan Simons <christiaan.simons@axon.tv>
35 */
36
37#include "lwip/opt.h"
38
39#if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
40
41#include "lwip/snmp_asn1.h"
42
52snmp_asn1_dec_type(struct pbuf *p, u16_t ofs, u8_t *type)
53{
54 u16_t plen, base;
55 u8_t *msg_ptr;
56
57 plen = 0;
58 while (p != NULL)
59 {
60 base = plen;
61 plen += p->len;
62 if (ofs < plen)
63 {
64 msg_ptr = (u8_t*)p->payload;
65 msg_ptr += ofs - base;
66 *type = *msg_ptr;
67 return ERR_OK;
68 }
69 p = p->next;
70 }
71 /* p == NULL, ofs >= plen */
72 return ERR_ARG;
73}
74
85snmp_asn1_dec_length(struct pbuf *p, u16_t ofs, u8_t *octets_used, u16_t *length)
86{
87 u16_t plen, base;
88 u8_t *msg_ptr;
89
90 plen = 0;
91 while (p != NULL)
92 {
93 base = plen;
94 plen += p->len;
95 if (ofs < plen)
96 {
97 msg_ptr = (u8_t*)p->payload;
98 msg_ptr += ofs - base;
99
100 if (*msg_ptr < 0x80)
101 {
102 /* primitive definite length format */
103 *octets_used = 1;
104 *length = *msg_ptr;
105 return ERR_OK;
106 }
107 else if (*msg_ptr == 0x80)
108 {
109 /* constructed indefinite length format, termination with two zero octets */
110 u8_t zeros;
111 u8_t i;
112
113 *length = 0;
114 zeros = 0;
115 while (zeros != 2)
116 {
117 i = 2;
118 while (i > 0)
119 {
120 i--;
121 (*length) += 1;
122 ofs += 1;
123 if (ofs >= plen)
124 {
125 /* next octet in next pbuf */
126 p = p->next;
127 if (p == NULL) { return ERR_ARG; }
128 msg_ptr = (u8_t*)p->payload;
129 plen += p->len;
130 }
131 else
132 {
133 /* next octet in same pbuf */
134 msg_ptr++;
135 }
136 if (*msg_ptr == 0)
137 {
138 zeros++;
139 if (zeros == 2)
140 {
141 /* stop while (i > 0) */
142 i = 0;
143 }
144 }
145 else
146 {
147 zeros = 0;
148 }
149 }
150 }
151 *octets_used = 1;
152 return ERR_OK;
153 }
154 else if (*msg_ptr == 0x81)
155 {
156 /* constructed definite length format, one octet */
157 ofs += 1;
158 if (ofs >= plen)
159 {
160 /* next octet in next pbuf */
161 p = p->next;
162 if (p == NULL) { return ERR_ARG; }
163 msg_ptr = (u8_t*)p->payload;
164 }
165 else
166 {
167 /* next octet in same pbuf */
168 msg_ptr++;
169 }
170 *length = *msg_ptr;
171 *octets_used = 2;
172 return ERR_OK;
173 }
174 else if (*msg_ptr == 0x82)
175 {
176 u8_t i;
177
178 /* constructed definite length format, two octets */
179 i = 2;
180 while (i > 0)
181 {
182 i--;
183 ofs += 1;
184 if (ofs >= plen)
185 {
186 /* next octet in next pbuf */
187 p = p->next;
188 if (p == NULL) { return ERR_ARG; }
189 msg_ptr = (u8_t*)p->payload;
190 plen += p->len;
191 }
192 else
193 {
194 /* next octet in same pbuf */
195 msg_ptr++;
196 }
197 if (i == 0)
198 {
199 /* least significant length octet */
200 *length |= *msg_ptr;
201 }
202 else
203 {
204 /* most significant length octet */
205 *length = (*msg_ptr) << 8;
206 }
207 }
208 *octets_used = 3;
209 return ERR_OK;
210 }
211 else
212 {
213 /* constructed definite length format 3..127 octets, this is too big (>64k) */
215 *octets_used = 1 + ((*msg_ptr) & 0x7f);
216 return ERR_ARG;
217 }
218 }
219 p = p->next;
220 }
221
222 /* p == NULL, ofs >= plen */
223 return ERR_ARG;
224}
225
239err_t
240snmp_asn1_dec_u32t(struct pbuf *p, u16_t ofs, u16_t len, u32_t *value)
241{
242 u16_t plen, base;
243 u8_t *msg_ptr;
244
245 plen = 0;
246 while (p != NULL)
247 {
248 base = plen;
249 plen += p->len;
250 if (ofs < plen)
251 {
252 msg_ptr = (u8_t*)p->payload;
253 msg_ptr += ofs - base;
254 if ((len > 0) && (len < 6))
255 {
256 /* start from zero */
257 *value = 0;
258 if (*msg_ptr & 0x80)
259 {
260 /* negative, expecting zero sign bit! */
261 return ERR_ARG;
262 }
263 else
264 {
265 /* positive */
266 if ((len > 1) && (*msg_ptr == 0))
267 {
268 /* skip leading "sign byte" octet 0x00 */
269 len--;
270 ofs += 1;
271 if (ofs >= plen)
272 {
273 /* next octet in next pbuf */
274 p = p->next;
275 if (p == NULL) { return ERR_ARG; }
276 msg_ptr = (u8_t*)p->payload;
277 plen += p->len;
278 }
279 else
280 {
281 /* next octet in same pbuf */
282 msg_ptr++;
283 }
284 }
285 }
286 /* OR octets with value */
287 while (len > 1)
288 {
289 len--;
290 *value |= *msg_ptr;
291 *value <<= 8;
292 ofs += 1;
293 if (ofs >= plen)
294 {
295 /* next octet in next pbuf */
296 p = p->next;
297 if (p == NULL) { return ERR_ARG; }
298 msg_ptr = (u8_t*)p->payload;
299 plen += p->len;
300 }
301 else
302 {
303 /* next octet in same pbuf */
304 msg_ptr++;
305 }
306 }
307 *value |= *msg_ptr;
308 return ERR_OK;
309 }
310 else
311 {
312 return ERR_ARG;
313 }
314 }
315 p = p->next;
316 }
317 /* p == NULL, ofs >= plen */
318 return ERR_ARG;
319}
320
332err_t
333snmp_asn1_dec_s32t(struct pbuf *p, u16_t ofs, u16_t len, s32_t *value)
334{
335 u16_t plen, base;
336 u8_t *msg_ptr;
337#if BYTE_ORDER == LITTLE_ENDIAN
338 u8_t *lsb_ptr = (u8_t*)value;
339#endif
340#if BYTE_ORDER == BIG_ENDIAN
341 u8_t *lsb_ptr = (u8_t*)value + sizeof(s32_t) - 1;
342#endif
343 u8_t sign;
344
345 plen = 0;
346 while (p != NULL)
347 {
348 base = plen;
349 plen += p->len;
350 if (ofs < plen)
351 {
352 msg_ptr = (u8_t*)p->payload;
353 msg_ptr += ofs - base;
354 if ((len > 0) && (len < 5))
355 {
356 if (*msg_ptr & 0x80)
357 {
358 /* negative, start from -1 */
359 *value = -1;
360 sign = 1;
361 }
362 else
363 {
364 /* positive, start from 0 */
365 *value = 0;
366 sign = 0;
367 }
368 /* OR/AND octets with value */
369 while (len > 1)
370 {
371 len--;
372 if (sign)
373 {
374 *lsb_ptr &= *msg_ptr;
375 *value <<= 8;
376 *lsb_ptr |= 255;
377 }
378 else
379 {
380 *lsb_ptr |= *msg_ptr;
381 *value <<= 8;
382 }
383 ofs += 1;
384 if (ofs >= plen)
385 {
386 /* next octet in next pbuf */
387 p = p->next;
388 if (p == NULL) { return ERR_ARG; }
389 msg_ptr = (u8_t*)p->payload;
390 plen += p->len;
391 }
392 else
393 {
394 /* next octet in same pbuf */
395 msg_ptr++;
396 }
397 }
398 if (sign)
399 {
400 *lsb_ptr &= *msg_ptr;
401 }
402 else
403 {
404 *lsb_ptr |= *msg_ptr;
405 }
406 return ERR_OK;
407 }
408 else
409 {
410 return ERR_ARG;
411 }
412 }
413 p = p->next;
414 }
415 /* p == NULL, ofs >= plen */
416 return ERR_ARG;
417}
418
428err_t
429snmp_asn1_dec_oid(struct pbuf *p, u16_t ofs, u16_t len, struct snmp_obj_id *oid)
430{
431 u16_t plen, base;
432 u8_t *msg_ptr;
433 s32_t *oid_ptr;
434
435 plen = 0;
436 while (p != NULL)
437 {
438 base = plen;
439 plen += p->len;
440 if (ofs < plen)
441 {
442 msg_ptr = (u8_t*)p->payload;
443 msg_ptr += ofs - base;
444
445 oid->len = 0;
446 oid_ptr = &oid->id[0];
447 if (len > 0)
448 {
449 /* first compressed octet */
450 if (*msg_ptr == 0x2B)
451 {
452 /* (most) common case 1.3 (iso.org) */
453 *oid_ptr = 1;
454 oid_ptr++;
455 *oid_ptr = 3;
456 oid_ptr++;
457 }
458 else if (*msg_ptr < 40)
459 {
460 *oid_ptr = 0;
461 oid_ptr++;
462 *oid_ptr = *msg_ptr;
463 oid_ptr++;
464 }
465 else if (*msg_ptr < 80)
466 {
467 *oid_ptr = 1;
468 oid_ptr++;
469 *oid_ptr = (*msg_ptr) - 40;
470 oid_ptr++;
471 }
472 else
473 {
474 *oid_ptr = 2;
475 oid_ptr++;
476 *oid_ptr = (*msg_ptr) - 80;
477 oid_ptr++;
478 }
479 oid->len = 2;
480 }
481 else
482 {
483 /* accepting zero length identifiers e.g. for
484 getnext operation. uncommon but valid */
485 return ERR_OK;
486 }
487 len--;
488 if (len > 0)
489 {
490 ofs += 1;
491 if (ofs >= plen)
492 {
493 /* next octet in next pbuf */
494 p = p->next;
495 if (p == NULL) { return ERR_ARG; }
496 msg_ptr = (u8_t*)p->payload;
497 plen += p->len;
498 }
499 else
500 {
501 /* next octet in same pbuf */
502 msg_ptr++;
503 }
504 }
505 while ((len > 0) && (oid->len < LWIP_SNMP_OBJ_ID_LEN))
506 {
507 /* sub-identifier uses multiple octets */
508 if (*msg_ptr & 0x80)
509 {
510 s32_t sub_id = 0;
511
512 while ((*msg_ptr & 0x80) && (len > 1))
513 {
514 len--;
515 sub_id = (sub_id << 7) + (*msg_ptr & ~0x80);
516 ofs += 1;
517 if (ofs >= plen)
518 {
519 /* next octet in next pbuf */
520 p = p->next;
521 if (p == NULL) { return ERR_ARG; }
522 msg_ptr = (u8_t*)p->payload;
523 plen += p->len;
524 }
525 else
526 {
527 /* next octet in same pbuf */
528 msg_ptr++;
529 }
530 }
531 if (!(*msg_ptr & 0x80) && (len > 0))
532 {
533 /* last octet sub-identifier */
534 len--;
535 sub_id = (sub_id << 7) + *msg_ptr;
536 *oid_ptr = sub_id;
537 }
538 }
539 else
540 {
541 /* !(*msg_ptr & 0x80) sub-identifier uses single octet */
542 len--;
543 *oid_ptr = *msg_ptr;
544 }
545 if (len > 0)
546 {
547 /* remaining oid bytes available ... */
548 ofs += 1;
549 if (ofs >= plen)
550 {
551 /* next octet in next pbuf */
552 p = p->next;
553 if (p == NULL) { return ERR_ARG; }
554 msg_ptr = (u8_t*)p->payload;
555 plen += p->len;
556 }
557 else
558 {
559 /* next octet in same pbuf */
560 msg_ptr++;
561 }
562 }
563 oid_ptr++;
564 oid->len++;
565 }
566 if (len == 0)
567 {
568 /* len == 0, end of oid */
569 return ERR_OK;
570 }
571 else
572 {
573 /* len > 0, oid->len == LWIP_SNMP_OBJ_ID_LEN or malformed encoding */
574 return ERR_ARG;
575 }
576
577 }
578 p = p->next;
579 }
580 /* p == NULL, ofs >= plen */
581 return ERR_ARG;
582}
583
595err_t
596snmp_asn1_dec_raw(struct pbuf *p, u16_t ofs, u16_t len, u16_t raw_len, u8_t *raw)
597{
598 u16_t plen, base;
599 u8_t *msg_ptr;
600
601 if (len > 0)
602 {
603 plen = 0;
604 while (p != NULL)
605 {
606 base = plen;
607 plen += p->len;
608 if (ofs < plen)
609 {
610 msg_ptr = (u8_t*)p->payload;
611 msg_ptr += ofs - base;
612 if (raw_len >= len)
613 {
614 while (len > 1)
615 {
616 /* copy len - 1 octets */
617 len--;
618 *raw = *msg_ptr;
619 raw++;
620 ofs += 1;
621 if (ofs >= plen)
622 {
623 /* next octet in next pbuf */
624 p = p->next;
625 if (p == NULL) { return ERR_ARG; }
626 msg_ptr = (u8_t*)p->payload;
627 plen += p->len;
628 }
629 else
630 {
631 /* next octet in same pbuf */
632 msg_ptr++;
633 }
634 }
635 /* copy last octet */
636 *raw = *msg_ptr;
637 return ERR_OK;
638 }
639 else
640 {
641 /* raw_len < len, not enough dst space */
642 return ERR_ARG;
643 }
644 }
645 p = p->next;
646 }
647 /* p == NULL, ofs >= plen */
648 return ERR_ARG;
649 }
650 else
651 {
652 /* len == 0, empty string */
653 return ERR_OK;
654 }
655}
656
657#endif /* LWIP_SNMP */
#define NULL
Definition: types.h:112
signed long s32_t
Definition: cc.h:30
unsigned long u32_t
Definition: cc.h:25
unsigned char u8_t
Definition: cc.h:23
unsigned short u16_t
Definition: cc.h:24
#define ERR_ARG
Definition: err.h:70
#define ERR_OK
Definition: err.h:52
s8_t err_t
Definition: err.h:47
GLuint GLuint GLsizei GLenum type
Definition: gl.h:1545
GLuint GLsizei GLsizei * length
Definition: glext.h:6040
GLfloat GLfloat p
Definition: glext.h:8902
GLenum GLsizei len
Definition: glext.h:6722
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble const GLfloat const GLdouble const GLfloat GLint i
Definition: glfuncs.h:248
if(dx< 0)
Definition: linetemp.h:194
#define sign(x)
Definition: mapdesc.cc:613
struct define * next
Definition: compiler.c:65
Definition: pbuf.h:79
Definition: pdh_main.c:94