NetTribute library with debug turned on in FShandler Donatien Garner -> Segundo Equipo -> this version

Committer:
hexley
Date:
Fri Nov 19 01:54:45 2010 +0000
Revision:
0:281d6ff68967

        

Who changed what in which revision?

UserRevisionLine numberNew contents of line
hexley 0:281d6ff68967 1 /**
hexley 0:281d6ff68967 2 * @file
hexley 0:281d6ff68967 3 * Abstract Syntax Notation One (ISO 8824, 8825) encoding
hexley 0:281d6ff68967 4 *
hexley 0:281d6ff68967 5 * @todo not optimised (yet), favor correctness over speed, favor speed over size
hexley 0:281d6ff68967 6 */
hexley 0:281d6ff68967 7
hexley 0:281d6ff68967 8 /*
hexley 0:281d6ff68967 9 * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
hexley 0:281d6ff68967 10 * All rights reserved.
hexley 0:281d6ff68967 11 *
hexley 0:281d6ff68967 12 * Redistribution and use in source and binary forms, with or without modification,
hexley 0:281d6ff68967 13 * are permitted provided that the following conditions are met:
hexley 0:281d6ff68967 14 *
hexley 0:281d6ff68967 15 * 1. Redistributions of source code must retain the above copyright notice,
hexley 0:281d6ff68967 16 * this list of conditions and the following disclaimer.
hexley 0:281d6ff68967 17 * 2. Redistributions in binary form must reproduce the above copyright notice,
hexley 0:281d6ff68967 18 * this list of conditions and the following disclaimer in the documentation
hexley 0:281d6ff68967 19 * and/or other materials provided with the distribution.
hexley 0:281d6ff68967 20 * 3. The name of the author may not be used to endorse or promote products
hexley 0:281d6ff68967 21 * derived from this software without specific prior written permission.
hexley 0:281d6ff68967 22 *
hexley 0:281d6ff68967 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
hexley 0:281d6ff68967 24 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
hexley 0:281d6ff68967 25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
hexley 0:281d6ff68967 26 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
hexley 0:281d6ff68967 27 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
hexley 0:281d6ff68967 28 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
hexley 0:281d6ff68967 29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
hexley 0:281d6ff68967 30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
hexley 0:281d6ff68967 31 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
hexley 0:281d6ff68967 32 * OF SUCH DAMAGE.
hexley 0:281d6ff68967 33 *
hexley 0:281d6ff68967 34 * Author: Christiaan Simons <christiaan.simons@axon.tv>
hexley 0:281d6ff68967 35 */
hexley 0:281d6ff68967 36
hexley 0:281d6ff68967 37 #include "lwip/opt.h"
hexley 0:281d6ff68967 38
hexley 0:281d6ff68967 39 #if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
hexley 0:281d6ff68967 40
hexley 0:281d6ff68967 41 #include "lwip/snmp_asn1.h"
hexley 0:281d6ff68967 42
hexley 0:281d6ff68967 43 /**
hexley 0:281d6ff68967 44 * Returns octet count for length.
hexley 0:281d6ff68967 45 *
hexley 0:281d6ff68967 46 * @param length
hexley 0:281d6ff68967 47 * @param octets_needed points to the return value
hexley 0:281d6ff68967 48 */
hexley 0:281d6ff68967 49 void
hexley 0:281d6ff68967 50 snmp_asn1_enc_length_cnt(u16_t length, u8_t *octets_needed)
hexley 0:281d6ff68967 51 {
hexley 0:281d6ff68967 52 if (length < 0x80U)
hexley 0:281d6ff68967 53 {
hexley 0:281d6ff68967 54 *octets_needed = 1;
hexley 0:281d6ff68967 55 }
hexley 0:281d6ff68967 56 else if (length < 0x100U)
hexley 0:281d6ff68967 57 {
hexley 0:281d6ff68967 58 *octets_needed = 2;
hexley 0:281d6ff68967 59 }
hexley 0:281d6ff68967 60 else
hexley 0:281d6ff68967 61 {
hexley 0:281d6ff68967 62 *octets_needed = 3;
hexley 0:281d6ff68967 63 }
hexley 0:281d6ff68967 64 }
hexley 0:281d6ff68967 65
hexley 0:281d6ff68967 66 /**
hexley 0:281d6ff68967 67 * Returns octet count for an u32_t.
hexley 0:281d6ff68967 68 *
hexley 0:281d6ff68967 69 * @param value
hexley 0:281d6ff68967 70 * @param octets_needed points to the return value
hexley 0:281d6ff68967 71 *
hexley 0:281d6ff68967 72 * @note ASN coded integers are _always_ signed. E.g. +0xFFFF is coded
hexley 0:281d6ff68967 73 * as 0x00,0xFF,0xFF. Note the leading sign octet. A positive value
hexley 0:281d6ff68967 74 * of 0xFFFFFFFF is preceded with 0x00 and the length is 5 octets!!
hexley 0:281d6ff68967 75 */
hexley 0:281d6ff68967 76 void
hexley 0:281d6ff68967 77 snmp_asn1_enc_u32t_cnt(u32_t value, u16_t *octets_needed)
hexley 0:281d6ff68967 78 {
hexley 0:281d6ff68967 79 if (value < 0x80UL)
hexley 0:281d6ff68967 80 {
hexley 0:281d6ff68967 81 *octets_needed = 1;
hexley 0:281d6ff68967 82 }
hexley 0:281d6ff68967 83 else if (value < 0x8000UL)
hexley 0:281d6ff68967 84 {
hexley 0:281d6ff68967 85 *octets_needed = 2;
hexley 0:281d6ff68967 86 }
hexley 0:281d6ff68967 87 else if (value < 0x800000UL)
hexley 0:281d6ff68967 88 {
hexley 0:281d6ff68967 89 *octets_needed = 3;
hexley 0:281d6ff68967 90 }
hexley 0:281d6ff68967 91 else if (value < 0x80000000UL)
hexley 0:281d6ff68967 92 {
hexley 0:281d6ff68967 93 *octets_needed = 4;
hexley 0:281d6ff68967 94 }
hexley 0:281d6ff68967 95 else
hexley 0:281d6ff68967 96 {
hexley 0:281d6ff68967 97 *octets_needed = 5;
hexley 0:281d6ff68967 98 }
hexley 0:281d6ff68967 99 }
hexley 0:281d6ff68967 100
hexley 0:281d6ff68967 101 /**
hexley 0:281d6ff68967 102 * Returns octet count for an s32_t.
hexley 0:281d6ff68967 103 *
hexley 0:281d6ff68967 104 * @param value
hexley 0:281d6ff68967 105 * @param octets_needed points to the return value
hexley 0:281d6ff68967 106 *
hexley 0:281d6ff68967 107 * @note ASN coded integers are _always_ signed.
hexley 0:281d6ff68967 108 */
hexley 0:281d6ff68967 109 void
hexley 0:281d6ff68967 110 snmp_asn1_enc_s32t_cnt(s32_t value, u16_t *octets_needed)
hexley 0:281d6ff68967 111 {
hexley 0:281d6ff68967 112 if (value < 0)
hexley 0:281d6ff68967 113 {
hexley 0:281d6ff68967 114 value = ~value;
hexley 0:281d6ff68967 115 }
hexley 0:281d6ff68967 116 if (value < 0x80L)
hexley 0:281d6ff68967 117 {
hexley 0:281d6ff68967 118 *octets_needed = 1;
hexley 0:281d6ff68967 119 }
hexley 0:281d6ff68967 120 else if (value < 0x8000L)
hexley 0:281d6ff68967 121 {
hexley 0:281d6ff68967 122 *octets_needed = 2;
hexley 0:281d6ff68967 123 }
hexley 0:281d6ff68967 124 else if (value < 0x800000L)
hexley 0:281d6ff68967 125 {
hexley 0:281d6ff68967 126 *octets_needed = 3;
hexley 0:281d6ff68967 127 }
hexley 0:281d6ff68967 128 else
hexley 0:281d6ff68967 129 {
hexley 0:281d6ff68967 130 *octets_needed = 4;
hexley 0:281d6ff68967 131 }
hexley 0:281d6ff68967 132 }
hexley 0:281d6ff68967 133
hexley 0:281d6ff68967 134 /**
hexley 0:281d6ff68967 135 * Returns octet count for an object identifier.
hexley 0:281d6ff68967 136 *
hexley 0:281d6ff68967 137 * @param ident_len object identifier array length
hexley 0:281d6ff68967 138 * @param ident points to object identifier array
hexley 0:281d6ff68967 139 * @param octets_needed points to the return value
hexley 0:281d6ff68967 140 */
hexley 0:281d6ff68967 141 void
hexley 0:281d6ff68967 142 snmp_asn1_enc_oid_cnt(u8_t ident_len, s32_t *ident, u16_t *octets_needed)
hexley 0:281d6ff68967 143 {
hexley 0:281d6ff68967 144 s32_t sub_id;
hexley 0:281d6ff68967 145 u8_t cnt;
hexley 0:281d6ff68967 146
hexley 0:281d6ff68967 147 cnt = 0;
hexley 0:281d6ff68967 148 if (ident_len > 1)
hexley 0:281d6ff68967 149 {
hexley 0:281d6ff68967 150 /* compressed prefix in one octet */
hexley 0:281d6ff68967 151 cnt++;
hexley 0:281d6ff68967 152 ident_len -= 2;
hexley 0:281d6ff68967 153 ident += 2;
hexley 0:281d6ff68967 154 }
hexley 0:281d6ff68967 155 while(ident_len > 0)
hexley 0:281d6ff68967 156 {
hexley 0:281d6ff68967 157 ident_len--;
hexley 0:281d6ff68967 158 sub_id = *ident;
hexley 0:281d6ff68967 159
hexley 0:281d6ff68967 160 sub_id >>= 7;
hexley 0:281d6ff68967 161 cnt++;
hexley 0:281d6ff68967 162 while(sub_id > 0)
hexley 0:281d6ff68967 163 {
hexley 0:281d6ff68967 164 sub_id >>= 7;
hexley 0:281d6ff68967 165 cnt++;
hexley 0:281d6ff68967 166 }
hexley 0:281d6ff68967 167 ident++;
hexley 0:281d6ff68967 168 }
hexley 0:281d6ff68967 169 *octets_needed = cnt;
hexley 0:281d6ff68967 170 }
hexley 0:281d6ff68967 171
hexley 0:281d6ff68967 172 /**
hexley 0:281d6ff68967 173 * Encodes ASN type field into a pbuf chained ASN1 msg.
hexley 0:281d6ff68967 174 *
hexley 0:281d6ff68967 175 * @param p points to output pbuf to encode value into
hexley 0:281d6ff68967 176 * @param ofs points to the offset within the pbuf chain
hexley 0:281d6ff68967 177 * @param type input ASN1 type
hexley 0:281d6ff68967 178 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
hexley 0:281d6ff68967 179 */
hexley 0:281d6ff68967 180 err_t
hexley 0:281d6ff68967 181 snmp_asn1_enc_type(struct pbuf *p, u16_t ofs, u8_t type)
hexley 0:281d6ff68967 182 {
hexley 0:281d6ff68967 183 u16_t plen, base;
hexley 0:281d6ff68967 184 u8_t *msg_ptr;
hexley 0:281d6ff68967 185
hexley 0:281d6ff68967 186 plen = 0;
hexley 0:281d6ff68967 187 while (p != NULL)
hexley 0:281d6ff68967 188 {
hexley 0:281d6ff68967 189 base = plen;
hexley 0:281d6ff68967 190 plen += p->len;
hexley 0:281d6ff68967 191 if (ofs < plen)
hexley 0:281d6ff68967 192 {
hexley 0:281d6ff68967 193 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 194 msg_ptr += ofs - base;
hexley 0:281d6ff68967 195 *msg_ptr = type;
hexley 0:281d6ff68967 196 return ERR_OK;
hexley 0:281d6ff68967 197 }
hexley 0:281d6ff68967 198 p = p->next;
hexley 0:281d6ff68967 199 }
hexley 0:281d6ff68967 200 /* p == NULL, ofs >= plen */
hexley 0:281d6ff68967 201 return ERR_ARG;
hexley 0:281d6ff68967 202 }
hexley 0:281d6ff68967 203
hexley 0:281d6ff68967 204 /**
hexley 0:281d6ff68967 205 * Encodes host order length field into a pbuf chained ASN1 msg.
hexley 0:281d6ff68967 206 *
hexley 0:281d6ff68967 207 * @param p points to output pbuf to encode length into
hexley 0:281d6ff68967 208 * @param ofs points to the offset within the pbuf chain
hexley 0:281d6ff68967 209 * @param length is the host order length to be encoded
hexley 0:281d6ff68967 210 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
hexley 0:281d6ff68967 211 */
hexley 0:281d6ff68967 212 err_t
hexley 0:281d6ff68967 213 snmp_asn1_enc_length(struct pbuf *p, u16_t ofs, u16_t length)
hexley 0:281d6ff68967 214 {
hexley 0:281d6ff68967 215 u16_t plen, base;
hexley 0:281d6ff68967 216 u8_t *msg_ptr;
hexley 0:281d6ff68967 217
hexley 0:281d6ff68967 218 plen = 0;
hexley 0:281d6ff68967 219 while (p != NULL)
hexley 0:281d6ff68967 220 {
hexley 0:281d6ff68967 221 base = plen;
hexley 0:281d6ff68967 222 plen += p->len;
hexley 0:281d6ff68967 223 if (ofs < plen)
hexley 0:281d6ff68967 224 {
hexley 0:281d6ff68967 225 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 226 msg_ptr += ofs - base;
hexley 0:281d6ff68967 227
hexley 0:281d6ff68967 228 if (length < 0x80)
hexley 0:281d6ff68967 229 {
hexley 0:281d6ff68967 230 *msg_ptr = (u8_t)length;
hexley 0:281d6ff68967 231 return ERR_OK;
hexley 0:281d6ff68967 232 }
hexley 0:281d6ff68967 233 else if (length < 0x100)
hexley 0:281d6ff68967 234 {
hexley 0:281d6ff68967 235 *msg_ptr = 0x81;
hexley 0:281d6ff68967 236 ofs += 1;
hexley 0:281d6ff68967 237 if (ofs >= plen)
hexley 0:281d6ff68967 238 {
hexley 0:281d6ff68967 239 /* next octet in next pbuf */
hexley 0:281d6ff68967 240 p = p->next;
hexley 0:281d6ff68967 241 if (p == NULL) { return ERR_ARG; }
hexley 0:281d6ff68967 242 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 243 }
hexley 0:281d6ff68967 244 else
hexley 0:281d6ff68967 245 {
hexley 0:281d6ff68967 246 /* next octet in same pbuf */
hexley 0:281d6ff68967 247 msg_ptr++;
hexley 0:281d6ff68967 248 }
hexley 0:281d6ff68967 249 *msg_ptr = (u8_t)length;
hexley 0:281d6ff68967 250 return ERR_OK;
hexley 0:281d6ff68967 251 }
hexley 0:281d6ff68967 252 else
hexley 0:281d6ff68967 253 {
hexley 0:281d6ff68967 254 u8_t i;
hexley 0:281d6ff68967 255
hexley 0:281d6ff68967 256 /* length >= 0x100 && length <= 0xFFFF */
hexley 0:281d6ff68967 257 *msg_ptr = 0x82;
hexley 0:281d6ff68967 258 i = 2;
hexley 0:281d6ff68967 259 while (i > 0)
hexley 0:281d6ff68967 260 {
hexley 0:281d6ff68967 261 i--;
hexley 0:281d6ff68967 262 ofs += 1;
hexley 0:281d6ff68967 263 if (ofs >= plen)
hexley 0:281d6ff68967 264 {
hexley 0:281d6ff68967 265 /* next octet in next pbuf */
hexley 0:281d6ff68967 266 p = p->next;
hexley 0:281d6ff68967 267 if (p == NULL) { return ERR_ARG; }
hexley 0:281d6ff68967 268 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 269 plen += p->len;
hexley 0:281d6ff68967 270 }
hexley 0:281d6ff68967 271 else
hexley 0:281d6ff68967 272 {
hexley 0:281d6ff68967 273 /* next octet in same pbuf */
hexley 0:281d6ff68967 274 msg_ptr++;
hexley 0:281d6ff68967 275 }
hexley 0:281d6ff68967 276 if (i == 0)
hexley 0:281d6ff68967 277 {
hexley 0:281d6ff68967 278 /* least significant length octet */
hexley 0:281d6ff68967 279 *msg_ptr = (u8_t)length;
hexley 0:281d6ff68967 280 }
hexley 0:281d6ff68967 281 else
hexley 0:281d6ff68967 282 {
hexley 0:281d6ff68967 283 /* most significant length octet */
hexley 0:281d6ff68967 284 *msg_ptr = (u8_t)(length >> 8);
hexley 0:281d6ff68967 285 }
hexley 0:281d6ff68967 286 }
hexley 0:281d6ff68967 287 return ERR_OK;
hexley 0:281d6ff68967 288 }
hexley 0:281d6ff68967 289 }
hexley 0:281d6ff68967 290 p = p->next;
hexley 0:281d6ff68967 291 }
hexley 0:281d6ff68967 292 /* p == NULL, ofs >= plen */
hexley 0:281d6ff68967 293 return ERR_ARG;
hexley 0:281d6ff68967 294 }
hexley 0:281d6ff68967 295
hexley 0:281d6ff68967 296 /**
hexley 0:281d6ff68967 297 * Encodes u32_t (counter, gauge, timeticks) into a pbuf chained ASN1 msg.
hexley 0:281d6ff68967 298 *
hexley 0:281d6ff68967 299 * @param p points to output pbuf to encode value into
hexley 0:281d6ff68967 300 * @param ofs points to the offset within the pbuf chain
hexley 0:281d6ff68967 301 * @param octets_needed encoding length (from snmp_asn1_enc_u32t_cnt())
hexley 0:281d6ff68967 302 * @param value is the host order u32_t value to be encoded
hexley 0:281d6ff68967 303 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
hexley 0:281d6ff68967 304 *
hexley 0:281d6ff68967 305 * @see snmp_asn1_enc_u32t_cnt()
hexley 0:281d6ff68967 306 */
hexley 0:281d6ff68967 307 err_t
hexley 0:281d6ff68967 308 snmp_asn1_enc_u32t(struct pbuf *p, u16_t ofs, u16_t octets_needed, u32_t value)
hexley 0:281d6ff68967 309 {
hexley 0:281d6ff68967 310 u16_t plen, base;
hexley 0:281d6ff68967 311 u8_t *msg_ptr;
hexley 0:281d6ff68967 312
hexley 0:281d6ff68967 313 plen = 0;
hexley 0:281d6ff68967 314 while (p != NULL)
hexley 0:281d6ff68967 315 {
hexley 0:281d6ff68967 316 base = plen;
hexley 0:281d6ff68967 317 plen += p->len;
hexley 0:281d6ff68967 318 if (ofs < plen)
hexley 0:281d6ff68967 319 {
hexley 0:281d6ff68967 320 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 321 msg_ptr += ofs - base;
hexley 0:281d6ff68967 322
hexley 0:281d6ff68967 323 if (octets_needed == 5)
hexley 0:281d6ff68967 324 {
hexley 0:281d6ff68967 325 /* not enough bits in 'value' add leading 0x00 */
hexley 0:281d6ff68967 326 octets_needed--;
hexley 0:281d6ff68967 327 *msg_ptr = 0x00;
hexley 0:281d6ff68967 328 ofs += 1;
hexley 0:281d6ff68967 329 if (ofs >= plen)
hexley 0:281d6ff68967 330 {
hexley 0:281d6ff68967 331 /* next octet in next pbuf */
hexley 0:281d6ff68967 332 p = p->next;
hexley 0:281d6ff68967 333 if (p == NULL) { return ERR_ARG; }
hexley 0:281d6ff68967 334 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 335 plen += p->len;
hexley 0:281d6ff68967 336 }
hexley 0:281d6ff68967 337 else
hexley 0:281d6ff68967 338 {
hexley 0:281d6ff68967 339 /* next octet in same pbuf */
hexley 0:281d6ff68967 340 msg_ptr++;
hexley 0:281d6ff68967 341 }
hexley 0:281d6ff68967 342 }
hexley 0:281d6ff68967 343 while (octets_needed > 1)
hexley 0:281d6ff68967 344 {
hexley 0:281d6ff68967 345 octets_needed--;
hexley 0:281d6ff68967 346 *msg_ptr = (u8_t)(value >> (octets_needed << 3));
hexley 0:281d6ff68967 347 ofs += 1;
hexley 0:281d6ff68967 348 if (ofs >= plen)
hexley 0:281d6ff68967 349 {
hexley 0:281d6ff68967 350 /* next octet in next pbuf */
hexley 0:281d6ff68967 351 p = p->next;
hexley 0:281d6ff68967 352 if (p == NULL) { return ERR_ARG; }
hexley 0:281d6ff68967 353 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 354 plen += p->len;
hexley 0:281d6ff68967 355 }
hexley 0:281d6ff68967 356 else
hexley 0:281d6ff68967 357 {
hexley 0:281d6ff68967 358 /* next octet in same pbuf */
hexley 0:281d6ff68967 359 msg_ptr++;
hexley 0:281d6ff68967 360 }
hexley 0:281d6ff68967 361 }
hexley 0:281d6ff68967 362 /* (only) one least significant octet */
hexley 0:281d6ff68967 363 *msg_ptr = (u8_t)value;
hexley 0:281d6ff68967 364 return ERR_OK;
hexley 0:281d6ff68967 365 }
hexley 0:281d6ff68967 366 p = p->next;
hexley 0:281d6ff68967 367 }
hexley 0:281d6ff68967 368 /* p == NULL, ofs >= plen */
hexley 0:281d6ff68967 369 return ERR_ARG;
hexley 0:281d6ff68967 370 }
hexley 0:281d6ff68967 371
hexley 0:281d6ff68967 372 /**
hexley 0:281d6ff68967 373 * Encodes s32_t integer into a pbuf chained ASN1 msg.
hexley 0:281d6ff68967 374 *
hexley 0:281d6ff68967 375 * @param p points to output pbuf to encode value into
hexley 0:281d6ff68967 376 * @param ofs points to the offset within the pbuf chain
hexley 0:281d6ff68967 377 * @param octets_needed encoding length (from snmp_asn1_enc_s32t_cnt())
hexley 0:281d6ff68967 378 * @param value is the host order s32_t value to be encoded
hexley 0:281d6ff68967 379 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
hexley 0:281d6ff68967 380 *
hexley 0:281d6ff68967 381 * @see snmp_asn1_enc_s32t_cnt()
hexley 0:281d6ff68967 382 */
hexley 0:281d6ff68967 383 err_t
hexley 0:281d6ff68967 384 snmp_asn1_enc_s32t(struct pbuf *p, u16_t ofs, u16_t octets_needed, s32_t value)
hexley 0:281d6ff68967 385 {
hexley 0:281d6ff68967 386 u16_t plen, base;
hexley 0:281d6ff68967 387 u8_t *msg_ptr;
hexley 0:281d6ff68967 388
hexley 0:281d6ff68967 389 plen = 0;
hexley 0:281d6ff68967 390 while (p != NULL)
hexley 0:281d6ff68967 391 {
hexley 0:281d6ff68967 392 base = plen;
hexley 0:281d6ff68967 393 plen += p->len;
hexley 0:281d6ff68967 394 if (ofs < plen)
hexley 0:281d6ff68967 395 {
hexley 0:281d6ff68967 396 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 397 msg_ptr += ofs - base;
hexley 0:281d6ff68967 398
hexley 0:281d6ff68967 399 while (octets_needed > 1)
hexley 0:281d6ff68967 400 {
hexley 0:281d6ff68967 401 octets_needed--;
hexley 0:281d6ff68967 402 *msg_ptr = (u8_t)(value >> (octets_needed << 3));
hexley 0:281d6ff68967 403 ofs += 1;
hexley 0:281d6ff68967 404 if (ofs >= plen)
hexley 0:281d6ff68967 405 {
hexley 0:281d6ff68967 406 /* next octet in next pbuf */
hexley 0:281d6ff68967 407 p = p->next;
hexley 0:281d6ff68967 408 if (p == NULL) { return ERR_ARG; }
hexley 0:281d6ff68967 409 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 410 plen += p->len;
hexley 0:281d6ff68967 411 }
hexley 0:281d6ff68967 412 else
hexley 0:281d6ff68967 413 {
hexley 0:281d6ff68967 414 /* next octet in same pbuf */
hexley 0:281d6ff68967 415 msg_ptr++;
hexley 0:281d6ff68967 416 }
hexley 0:281d6ff68967 417 }
hexley 0:281d6ff68967 418 /* (only) one least significant octet */
hexley 0:281d6ff68967 419 *msg_ptr = (u8_t)value;
hexley 0:281d6ff68967 420 return ERR_OK;
hexley 0:281d6ff68967 421 }
hexley 0:281d6ff68967 422 p = p->next;
hexley 0:281d6ff68967 423 }
hexley 0:281d6ff68967 424 /* p == NULL, ofs >= plen */
hexley 0:281d6ff68967 425 return ERR_ARG;
hexley 0:281d6ff68967 426 }
hexley 0:281d6ff68967 427
hexley 0:281d6ff68967 428 /**
hexley 0:281d6ff68967 429 * Encodes object identifier into a pbuf chained ASN1 msg.
hexley 0:281d6ff68967 430 *
hexley 0:281d6ff68967 431 * @param p points to output pbuf to encode oid into
hexley 0:281d6ff68967 432 * @param ofs points to the offset within the pbuf chain
hexley 0:281d6ff68967 433 * @param ident_len object identifier array length
hexley 0:281d6ff68967 434 * @param ident points to object identifier array
hexley 0:281d6ff68967 435 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
hexley 0:281d6ff68967 436 */
hexley 0:281d6ff68967 437 err_t
hexley 0:281d6ff68967 438 snmp_asn1_enc_oid(struct pbuf *p, u16_t ofs, u8_t ident_len, s32_t *ident)
hexley 0:281d6ff68967 439 {
hexley 0:281d6ff68967 440 u16_t plen, base;
hexley 0:281d6ff68967 441 u8_t *msg_ptr;
hexley 0:281d6ff68967 442
hexley 0:281d6ff68967 443 plen = 0;
hexley 0:281d6ff68967 444 while (p != NULL)
hexley 0:281d6ff68967 445 {
hexley 0:281d6ff68967 446 base = plen;
hexley 0:281d6ff68967 447 plen += p->len;
hexley 0:281d6ff68967 448 if (ofs < plen)
hexley 0:281d6ff68967 449 {
hexley 0:281d6ff68967 450 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 451 msg_ptr += ofs - base;
hexley 0:281d6ff68967 452
hexley 0:281d6ff68967 453 if (ident_len > 1)
hexley 0:281d6ff68967 454 {
hexley 0:281d6ff68967 455 if ((ident[0] == 1) && (ident[1] == 3))
hexley 0:281d6ff68967 456 {
hexley 0:281d6ff68967 457 /* compressed (most common) prefix .iso.org */
hexley 0:281d6ff68967 458 *msg_ptr = 0x2b;
hexley 0:281d6ff68967 459 }
hexley 0:281d6ff68967 460 else
hexley 0:281d6ff68967 461 {
hexley 0:281d6ff68967 462 /* calculate prefix */
hexley 0:281d6ff68967 463 *msg_ptr = (u8_t)((ident[0] * 40) + ident[1]);
hexley 0:281d6ff68967 464 }
hexley 0:281d6ff68967 465 ofs += 1;
hexley 0:281d6ff68967 466 if (ofs >= plen)
hexley 0:281d6ff68967 467 {
hexley 0:281d6ff68967 468 /* next octet in next pbuf */
hexley 0:281d6ff68967 469 p = p->next;
hexley 0:281d6ff68967 470 if (p == NULL) { return ERR_ARG; }
hexley 0:281d6ff68967 471 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 472 plen += p->len;
hexley 0:281d6ff68967 473 }
hexley 0:281d6ff68967 474 else
hexley 0:281d6ff68967 475 {
hexley 0:281d6ff68967 476 /* next octet in same pbuf */
hexley 0:281d6ff68967 477 msg_ptr++;
hexley 0:281d6ff68967 478 }
hexley 0:281d6ff68967 479 ident_len -= 2;
hexley 0:281d6ff68967 480 ident += 2;
hexley 0:281d6ff68967 481 }
hexley 0:281d6ff68967 482 else
hexley 0:281d6ff68967 483 {
hexley 0:281d6ff68967 484 /* @bug: allow empty varbinds for symmetry (we must decode them for getnext), allow partial compression?? */
hexley 0:281d6ff68967 485 /* ident_len <= 1, at least we need zeroDotZero (0.0) (ident_len == 2) */
hexley 0:281d6ff68967 486 return ERR_ARG;
hexley 0:281d6ff68967 487 }
hexley 0:281d6ff68967 488 while (ident_len > 0)
hexley 0:281d6ff68967 489 {
hexley 0:281d6ff68967 490 s32_t sub_id;
hexley 0:281d6ff68967 491 u8_t shift, tail;
hexley 0:281d6ff68967 492
hexley 0:281d6ff68967 493 ident_len--;
hexley 0:281d6ff68967 494 sub_id = *ident;
hexley 0:281d6ff68967 495 tail = 0;
hexley 0:281d6ff68967 496 shift = 28;
hexley 0:281d6ff68967 497 while(shift > 0)
hexley 0:281d6ff68967 498 {
hexley 0:281d6ff68967 499 u8_t code;
hexley 0:281d6ff68967 500
hexley 0:281d6ff68967 501 code = (u8_t)(sub_id >> shift);
hexley 0:281d6ff68967 502 if ((code != 0) || (tail != 0))
hexley 0:281d6ff68967 503 {
hexley 0:281d6ff68967 504 tail = 1;
hexley 0:281d6ff68967 505 *msg_ptr = code | 0x80;
hexley 0:281d6ff68967 506 ofs += 1;
hexley 0:281d6ff68967 507 if (ofs >= plen)
hexley 0:281d6ff68967 508 {
hexley 0:281d6ff68967 509 /* next octet in next pbuf */
hexley 0:281d6ff68967 510 p = p->next;
hexley 0:281d6ff68967 511 if (p == NULL) { return ERR_ARG; }
hexley 0:281d6ff68967 512 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 513 plen += p->len;
hexley 0:281d6ff68967 514 }
hexley 0:281d6ff68967 515 else
hexley 0:281d6ff68967 516 {
hexley 0:281d6ff68967 517 /* next octet in same pbuf */
hexley 0:281d6ff68967 518 msg_ptr++;
hexley 0:281d6ff68967 519 }
hexley 0:281d6ff68967 520 }
hexley 0:281d6ff68967 521 shift -= 7;
hexley 0:281d6ff68967 522 }
hexley 0:281d6ff68967 523 *msg_ptr = (u8_t)sub_id & 0x7F;
hexley 0:281d6ff68967 524 if (ident_len > 0)
hexley 0:281d6ff68967 525 {
hexley 0:281d6ff68967 526 ofs += 1;
hexley 0:281d6ff68967 527 if (ofs >= plen)
hexley 0:281d6ff68967 528 {
hexley 0:281d6ff68967 529 /* next octet in next pbuf */
hexley 0:281d6ff68967 530 p = p->next;
hexley 0:281d6ff68967 531 if (p == NULL) { return ERR_ARG; }
hexley 0:281d6ff68967 532 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 533 plen += p->len;
hexley 0:281d6ff68967 534 }
hexley 0:281d6ff68967 535 else
hexley 0:281d6ff68967 536 {
hexley 0:281d6ff68967 537 /* next octet in same pbuf */
hexley 0:281d6ff68967 538 msg_ptr++;
hexley 0:281d6ff68967 539 }
hexley 0:281d6ff68967 540 }
hexley 0:281d6ff68967 541 /* proceed to next sub-identifier */
hexley 0:281d6ff68967 542 ident++;
hexley 0:281d6ff68967 543 }
hexley 0:281d6ff68967 544 return ERR_OK;
hexley 0:281d6ff68967 545 }
hexley 0:281d6ff68967 546 p = p->next;
hexley 0:281d6ff68967 547 }
hexley 0:281d6ff68967 548 /* p == NULL, ofs >= plen */
hexley 0:281d6ff68967 549 return ERR_ARG;
hexley 0:281d6ff68967 550 }
hexley 0:281d6ff68967 551
hexley 0:281d6ff68967 552 /**
hexley 0:281d6ff68967 553 * Encodes raw data (octet string, opaque) into a pbuf chained ASN1 msg.
hexley 0:281d6ff68967 554 *
hexley 0:281d6ff68967 555 * @param p points to output pbuf to encode raw data into
hexley 0:281d6ff68967 556 * @param ofs points to the offset within the pbuf chain
hexley 0:281d6ff68967 557 * @param raw_len raw data length
hexley 0:281d6ff68967 558 * @param raw points raw data
hexley 0:281d6ff68967 559 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
hexley 0:281d6ff68967 560 */
hexley 0:281d6ff68967 561 err_t
hexley 0:281d6ff68967 562 snmp_asn1_enc_raw(struct pbuf *p, u16_t ofs, u16_t raw_len, u8_t *raw)
hexley 0:281d6ff68967 563 {
hexley 0:281d6ff68967 564 u16_t plen, base;
hexley 0:281d6ff68967 565 u8_t *msg_ptr;
hexley 0:281d6ff68967 566
hexley 0:281d6ff68967 567 plen = 0;
hexley 0:281d6ff68967 568 while (p != NULL)
hexley 0:281d6ff68967 569 {
hexley 0:281d6ff68967 570 base = plen;
hexley 0:281d6ff68967 571 plen += p->len;
hexley 0:281d6ff68967 572 if (ofs < plen)
hexley 0:281d6ff68967 573 {
hexley 0:281d6ff68967 574 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 575 msg_ptr += ofs - base;
hexley 0:281d6ff68967 576
hexley 0:281d6ff68967 577 while (raw_len > 1)
hexley 0:281d6ff68967 578 {
hexley 0:281d6ff68967 579 /* copy raw_len - 1 octets */
hexley 0:281d6ff68967 580 raw_len--;
hexley 0:281d6ff68967 581 *msg_ptr = *raw;
hexley 0:281d6ff68967 582 raw++;
hexley 0:281d6ff68967 583 ofs += 1;
hexley 0:281d6ff68967 584 if (ofs >= plen)
hexley 0:281d6ff68967 585 {
hexley 0:281d6ff68967 586 /* next octet in next pbuf */
hexley 0:281d6ff68967 587 p = p->next;
hexley 0:281d6ff68967 588 if (p == NULL) { return ERR_ARG; }
hexley 0:281d6ff68967 589 msg_ptr = (u8_t*)p->payload;
hexley 0:281d6ff68967 590 plen += p->len;
hexley 0:281d6ff68967 591 }
hexley 0:281d6ff68967 592 else
hexley 0:281d6ff68967 593 {
hexley 0:281d6ff68967 594 /* next octet in same pbuf */
hexley 0:281d6ff68967 595 msg_ptr++;
hexley 0:281d6ff68967 596 }
hexley 0:281d6ff68967 597 }
hexley 0:281d6ff68967 598 if (raw_len > 0)
hexley 0:281d6ff68967 599 {
hexley 0:281d6ff68967 600 /* copy last or single octet */
hexley 0:281d6ff68967 601 *msg_ptr = *raw;
hexley 0:281d6ff68967 602 }
hexley 0:281d6ff68967 603 return ERR_OK;
hexley 0:281d6ff68967 604 }
hexley 0:281d6ff68967 605 p = p->next;
hexley 0:281d6ff68967 606 }
hexley 0:281d6ff68967 607 /* p == NULL, ofs >= plen */
hexley 0:281d6ff68967 608 return ERR_ARG;
hexley 0:281d6ff68967 609 }
hexley 0:281d6ff68967 610
hexley 0:281d6ff68967 611 #endif /* LWIP_SNMP */