Donatien Garnier / lwip_ppp_ethernet

Dependents:   NetworkingCoreLib

Committer:
donatien
Date:
Thu May 24 15:53:48 2012 +0000
Revision:
0:8e01dca41002
Merge with Emilio's LwIp

Who changed what in which revision?

UserRevisionLine numberNew contents of line
donatien 0:8e01dca41002 1 /**
donatien 0:8e01dca41002 2 * @file
donatien 0:8e01dca41002 3 * Abstract Syntax Notation One (ISO 8824, 8825) encoding
donatien 0:8e01dca41002 4 *
donatien 0:8e01dca41002 5 * @todo not optimised (yet), favor correctness over speed, favor speed over size
donatien 0:8e01dca41002 6 */
donatien 0:8e01dca41002 7
donatien 0:8e01dca41002 8 /*
donatien 0:8e01dca41002 9 * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
donatien 0:8e01dca41002 10 * All rights reserved.
donatien 0:8e01dca41002 11 *
donatien 0:8e01dca41002 12 * Redistribution and use in source and binary forms, with or without modification,
donatien 0:8e01dca41002 13 * are permitted provided that the following conditions are met:
donatien 0:8e01dca41002 14 *
donatien 0:8e01dca41002 15 * 1. Redistributions of source code must retain the above copyright notice,
donatien 0:8e01dca41002 16 * this list of conditions and the following disclaimer.
donatien 0:8e01dca41002 17 * 2. Redistributions in binary form must reproduce the above copyright notice,
donatien 0:8e01dca41002 18 * this list of conditions and the following disclaimer in the documentation
donatien 0:8e01dca41002 19 * and/or other materials provided with the distribution.
donatien 0:8e01dca41002 20 * 3. The name of the author may not be used to endorse or promote products
donatien 0:8e01dca41002 21 * derived from this software without specific prior written permission.
donatien 0:8e01dca41002 22 *
donatien 0:8e01dca41002 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
donatien 0:8e01dca41002 24 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
donatien 0:8e01dca41002 25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
donatien 0:8e01dca41002 26 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
donatien 0:8e01dca41002 27 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
donatien 0:8e01dca41002 28 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
donatien 0:8e01dca41002 29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
donatien 0:8e01dca41002 30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
donatien 0:8e01dca41002 31 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
donatien 0:8e01dca41002 32 * OF SUCH DAMAGE.
donatien 0:8e01dca41002 33 *
donatien 0:8e01dca41002 34 * Author: Christiaan Simons <christiaan.simons@axon.tv>
donatien 0:8e01dca41002 35 */
donatien 0:8e01dca41002 36
donatien 0:8e01dca41002 37 #include "lwip/opt.h"
donatien 0:8e01dca41002 38
donatien 0:8e01dca41002 39 #if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
donatien 0:8e01dca41002 40
donatien 0:8e01dca41002 41 #include "lwip/snmp_asn1.h"
donatien 0:8e01dca41002 42
donatien 0:8e01dca41002 43 /**
donatien 0:8e01dca41002 44 * Returns octet count for length.
donatien 0:8e01dca41002 45 *
donatien 0:8e01dca41002 46 * @param length
donatien 0:8e01dca41002 47 * @param octets_needed points to the return value
donatien 0:8e01dca41002 48 */
donatien 0:8e01dca41002 49 void
donatien 0:8e01dca41002 50 snmp_asn1_enc_length_cnt(u16_t length, u8_t *octets_needed)
donatien 0:8e01dca41002 51 {
donatien 0:8e01dca41002 52 if (length < 0x80U)
donatien 0:8e01dca41002 53 {
donatien 0:8e01dca41002 54 *octets_needed = 1;
donatien 0:8e01dca41002 55 }
donatien 0:8e01dca41002 56 else if (length < 0x100U)
donatien 0:8e01dca41002 57 {
donatien 0:8e01dca41002 58 *octets_needed = 2;
donatien 0:8e01dca41002 59 }
donatien 0:8e01dca41002 60 else
donatien 0:8e01dca41002 61 {
donatien 0:8e01dca41002 62 *octets_needed = 3;
donatien 0:8e01dca41002 63 }
donatien 0:8e01dca41002 64 }
donatien 0:8e01dca41002 65
donatien 0:8e01dca41002 66 /**
donatien 0:8e01dca41002 67 * Returns octet count for an u32_t.
donatien 0:8e01dca41002 68 *
donatien 0:8e01dca41002 69 * @param value
donatien 0:8e01dca41002 70 * @param octets_needed points to the return value
donatien 0:8e01dca41002 71 *
donatien 0:8e01dca41002 72 * @note ASN coded integers are _always_ signed. E.g. +0xFFFF is coded
donatien 0:8e01dca41002 73 * as 0x00,0xFF,0xFF. Note the leading sign octet. A positive value
donatien 0:8e01dca41002 74 * of 0xFFFFFFFF is preceded with 0x00 and the length is 5 octets!!
donatien 0:8e01dca41002 75 */
donatien 0:8e01dca41002 76 void
donatien 0:8e01dca41002 77 snmp_asn1_enc_u32t_cnt(u32_t value, u16_t *octets_needed)
donatien 0:8e01dca41002 78 {
donatien 0:8e01dca41002 79 if (value < 0x80UL)
donatien 0:8e01dca41002 80 {
donatien 0:8e01dca41002 81 *octets_needed = 1;
donatien 0:8e01dca41002 82 }
donatien 0:8e01dca41002 83 else if (value < 0x8000UL)
donatien 0:8e01dca41002 84 {
donatien 0:8e01dca41002 85 *octets_needed = 2;
donatien 0:8e01dca41002 86 }
donatien 0:8e01dca41002 87 else if (value < 0x800000UL)
donatien 0:8e01dca41002 88 {
donatien 0:8e01dca41002 89 *octets_needed = 3;
donatien 0:8e01dca41002 90 }
donatien 0:8e01dca41002 91 else if (value < 0x80000000UL)
donatien 0:8e01dca41002 92 {
donatien 0:8e01dca41002 93 *octets_needed = 4;
donatien 0:8e01dca41002 94 }
donatien 0:8e01dca41002 95 else
donatien 0:8e01dca41002 96 {
donatien 0:8e01dca41002 97 *octets_needed = 5;
donatien 0:8e01dca41002 98 }
donatien 0:8e01dca41002 99 }
donatien 0:8e01dca41002 100
donatien 0:8e01dca41002 101 /**
donatien 0:8e01dca41002 102 * Returns octet count for an s32_t.
donatien 0:8e01dca41002 103 *
donatien 0:8e01dca41002 104 * @param value
donatien 0:8e01dca41002 105 * @param octets_needed points to the return value
donatien 0:8e01dca41002 106 *
donatien 0:8e01dca41002 107 * @note ASN coded integers are _always_ signed.
donatien 0:8e01dca41002 108 */
donatien 0:8e01dca41002 109 void
donatien 0:8e01dca41002 110 snmp_asn1_enc_s32t_cnt(s32_t value, u16_t *octets_needed)
donatien 0:8e01dca41002 111 {
donatien 0:8e01dca41002 112 if (value < 0)
donatien 0:8e01dca41002 113 {
donatien 0:8e01dca41002 114 value = ~value;
donatien 0:8e01dca41002 115 }
donatien 0:8e01dca41002 116 if (value < 0x80L)
donatien 0:8e01dca41002 117 {
donatien 0:8e01dca41002 118 *octets_needed = 1;
donatien 0:8e01dca41002 119 }
donatien 0:8e01dca41002 120 else if (value < 0x8000L)
donatien 0:8e01dca41002 121 {
donatien 0:8e01dca41002 122 *octets_needed = 2;
donatien 0:8e01dca41002 123 }
donatien 0:8e01dca41002 124 else if (value < 0x800000L)
donatien 0:8e01dca41002 125 {
donatien 0:8e01dca41002 126 *octets_needed = 3;
donatien 0:8e01dca41002 127 }
donatien 0:8e01dca41002 128 else
donatien 0:8e01dca41002 129 {
donatien 0:8e01dca41002 130 *octets_needed = 4;
donatien 0:8e01dca41002 131 }
donatien 0:8e01dca41002 132 }
donatien 0:8e01dca41002 133
donatien 0:8e01dca41002 134 /**
donatien 0:8e01dca41002 135 * Returns octet count for an object identifier.
donatien 0:8e01dca41002 136 *
donatien 0:8e01dca41002 137 * @param ident_len object identifier array length
donatien 0:8e01dca41002 138 * @param ident points to object identifier array
donatien 0:8e01dca41002 139 * @param octets_needed points to the return value
donatien 0:8e01dca41002 140 */
donatien 0:8e01dca41002 141 void
donatien 0:8e01dca41002 142 snmp_asn1_enc_oid_cnt(u8_t ident_len, s32_t *ident, u16_t *octets_needed)
donatien 0:8e01dca41002 143 {
donatien 0:8e01dca41002 144 s32_t sub_id;
donatien 0:8e01dca41002 145 u8_t cnt;
donatien 0:8e01dca41002 146
donatien 0:8e01dca41002 147 cnt = 0;
donatien 0:8e01dca41002 148 if (ident_len > 1)
donatien 0:8e01dca41002 149 {
donatien 0:8e01dca41002 150 /* compressed prefix in one octet */
donatien 0:8e01dca41002 151 cnt++;
donatien 0:8e01dca41002 152 ident_len -= 2;
donatien 0:8e01dca41002 153 ident += 2;
donatien 0:8e01dca41002 154 }
donatien 0:8e01dca41002 155 while(ident_len > 0)
donatien 0:8e01dca41002 156 {
donatien 0:8e01dca41002 157 ident_len--;
donatien 0:8e01dca41002 158 sub_id = *ident;
donatien 0:8e01dca41002 159
donatien 0:8e01dca41002 160 sub_id >>= 7;
donatien 0:8e01dca41002 161 cnt++;
donatien 0:8e01dca41002 162 while(sub_id > 0)
donatien 0:8e01dca41002 163 {
donatien 0:8e01dca41002 164 sub_id >>= 7;
donatien 0:8e01dca41002 165 cnt++;
donatien 0:8e01dca41002 166 }
donatien 0:8e01dca41002 167 ident++;
donatien 0:8e01dca41002 168 }
donatien 0:8e01dca41002 169 *octets_needed = cnt;
donatien 0:8e01dca41002 170 }
donatien 0:8e01dca41002 171
donatien 0:8e01dca41002 172 /**
donatien 0:8e01dca41002 173 * Encodes ASN type field into a pbuf chained ASN1 msg.
donatien 0:8e01dca41002 174 *
donatien 0:8e01dca41002 175 * @param p points to output pbuf to encode value into
donatien 0:8e01dca41002 176 * @param ofs points to the offset within the pbuf chain
donatien 0:8e01dca41002 177 * @param type input ASN1 type
donatien 0:8e01dca41002 178 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
donatien 0:8e01dca41002 179 */
donatien 0:8e01dca41002 180 err_t
donatien 0:8e01dca41002 181 snmp_asn1_enc_type(struct pbuf *p, u16_t ofs, u8_t type)
donatien 0:8e01dca41002 182 {
donatien 0:8e01dca41002 183 u16_t plen, base;
donatien 0:8e01dca41002 184 u8_t *msg_ptr;
donatien 0:8e01dca41002 185
donatien 0:8e01dca41002 186 plen = 0;
donatien 0:8e01dca41002 187 while (p != NULL)
donatien 0:8e01dca41002 188 {
donatien 0:8e01dca41002 189 base = plen;
donatien 0:8e01dca41002 190 plen += p->len;
donatien 0:8e01dca41002 191 if (ofs < plen)
donatien 0:8e01dca41002 192 {
donatien 0:8e01dca41002 193 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 194 msg_ptr += ofs - base;
donatien 0:8e01dca41002 195 *msg_ptr = type;
donatien 0:8e01dca41002 196 return ERR_OK;
donatien 0:8e01dca41002 197 }
donatien 0:8e01dca41002 198 p = p->next;
donatien 0:8e01dca41002 199 }
donatien 0:8e01dca41002 200 /* p == NULL, ofs >= plen */
donatien 0:8e01dca41002 201 return ERR_ARG;
donatien 0:8e01dca41002 202 }
donatien 0:8e01dca41002 203
donatien 0:8e01dca41002 204 /**
donatien 0:8e01dca41002 205 * Encodes host order length field into a pbuf chained ASN1 msg.
donatien 0:8e01dca41002 206 *
donatien 0:8e01dca41002 207 * @param p points to output pbuf to encode length into
donatien 0:8e01dca41002 208 * @param ofs points to the offset within the pbuf chain
donatien 0:8e01dca41002 209 * @param length is the host order length to be encoded
donatien 0:8e01dca41002 210 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
donatien 0:8e01dca41002 211 */
donatien 0:8e01dca41002 212 err_t
donatien 0:8e01dca41002 213 snmp_asn1_enc_length(struct pbuf *p, u16_t ofs, u16_t length)
donatien 0:8e01dca41002 214 {
donatien 0:8e01dca41002 215 u16_t plen, base;
donatien 0:8e01dca41002 216 u8_t *msg_ptr;
donatien 0:8e01dca41002 217
donatien 0:8e01dca41002 218 plen = 0;
donatien 0:8e01dca41002 219 while (p != NULL)
donatien 0:8e01dca41002 220 {
donatien 0:8e01dca41002 221 base = plen;
donatien 0:8e01dca41002 222 plen += p->len;
donatien 0:8e01dca41002 223 if (ofs < plen)
donatien 0:8e01dca41002 224 {
donatien 0:8e01dca41002 225 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 226 msg_ptr += ofs - base;
donatien 0:8e01dca41002 227
donatien 0:8e01dca41002 228 if (length < 0x80)
donatien 0:8e01dca41002 229 {
donatien 0:8e01dca41002 230 *msg_ptr = (u8_t)length;
donatien 0:8e01dca41002 231 return ERR_OK;
donatien 0:8e01dca41002 232 }
donatien 0:8e01dca41002 233 else if (length < 0x100)
donatien 0:8e01dca41002 234 {
donatien 0:8e01dca41002 235 *msg_ptr = 0x81;
donatien 0:8e01dca41002 236 ofs += 1;
donatien 0:8e01dca41002 237 if (ofs >= plen)
donatien 0:8e01dca41002 238 {
donatien 0:8e01dca41002 239 /* next octet in next pbuf */
donatien 0:8e01dca41002 240 p = p->next;
donatien 0:8e01dca41002 241 if (p == NULL) { return ERR_ARG; }
donatien 0:8e01dca41002 242 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 243 }
donatien 0:8e01dca41002 244 else
donatien 0:8e01dca41002 245 {
donatien 0:8e01dca41002 246 /* next octet in same pbuf */
donatien 0:8e01dca41002 247 msg_ptr++;
donatien 0:8e01dca41002 248 }
donatien 0:8e01dca41002 249 *msg_ptr = (u8_t)length;
donatien 0:8e01dca41002 250 return ERR_OK;
donatien 0:8e01dca41002 251 }
donatien 0:8e01dca41002 252 else
donatien 0:8e01dca41002 253 {
donatien 0:8e01dca41002 254 u8_t i;
donatien 0:8e01dca41002 255
donatien 0:8e01dca41002 256 /* length >= 0x100 && length <= 0xFFFF */
donatien 0:8e01dca41002 257 *msg_ptr = 0x82;
donatien 0:8e01dca41002 258 i = 2;
donatien 0:8e01dca41002 259 while (i > 0)
donatien 0:8e01dca41002 260 {
donatien 0:8e01dca41002 261 i--;
donatien 0:8e01dca41002 262 ofs += 1;
donatien 0:8e01dca41002 263 if (ofs >= plen)
donatien 0:8e01dca41002 264 {
donatien 0:8e01dca41002 265 /* next octet in next pbuf */
donatien 0:8e01dca41002 266 p = p->next;
donatien 0:8e01dca41002 267 if (p == NULL) { return ERR_ARG; }
donatien 0:8e01dca41002 268 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 269 plen += p->len;
donatien 0:8e01dca41002 270 }
donatien 0:8e01dca41002 271 else
donatien 0:8e01dca41002 272 {
donatien 0:8e01dca41002 273 /* next octet in same pbuf */
donatien 0:8e01dca41002 274 msg_ptr++;
donatien 0:8e01dca41002 275 }
donatien 0:8e01dca41002 276 if (i == 0)
donatien 0:8e01dca41002 277 {
donatien 0:8e01dca41002 278 /* least significant length octet */
donatien 0:8e01dca41002 279 *msg_ptr = (u8_t)length;
donatien 0:8e01dca41002 280 }
donatien 0:8e01dca41002 281 else
donatien 0:8e01dca41002 282 {
donatien 0:8e01dca41002 283 /* most significant length octet */
donatien 0:8e01dca41002 284 *msg_ptr = (u8_t)(length >> 8);
donatien 0:8e01dca41002 285 }
donatien 0:8e01dca41002 286 }
donatien 0:8e01dca41002 287 return ERR_OK;
donatien 0:8e01dca41002 288 }
donatien 0:8e01dca41002 289 }
donatien 0:8e01dca41002 290 p = p->next;
donatien 0:8e01dca41002 291 }
donatien 0:8e01dca41002 292 /* p == NULL, ofs >= plen */
donatien 0:8e01dca41002 293 return ERR_ARG;
donatien 0:8e01dca41002 294 }
donatien 0:8e01dca41002 295
donatien 0:8e01dca41002 296 /**
donatien 0:8e01dca41002 297 * Encodes u32_t (counter, gauge, timeticks) into a pbuf chained ASN1 msg.
donatien 0:8e01dca41002 298 *
donatien 0:8e01dca41002 299 * @param p points to output pbuf to encode value into
donatien 0:8e01dca41002 300 * @param ofs points to the offset within the pbuf chain
donatien 0:8e01dca41002 301 * @param octets_needed encoding length (from snmp_asn1_enc_u32t_cnt())
donatien 0:8e01dca41002 302 * @param value is the host order u32_t value to be encoded
donatien 0:8e01dca41002 303 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
donatien 0:8e01dca41002 304 *
donatien 0:8e01dca41002 305 * @see snmp_asn1_enc_u32t_cnt()
donatien 0:8e01dca41002 306 */
donatien 0:8e01dca41002 307 err_t
donatien 0:8e01dca41002 308 snmp_asn1_enc_u32t(struct pbuf *p, u16_t ofs, u16_t octets_needed, u32_t value)
donatien 0:8e01dca41002 309 {
donatien 0:8e01dca41002 310 u16_t plen, base;
donatien 0:8e01dca41002 311 u8_t *msg_ptr;
donatien 0:8e01dca41002 312
donatien 0:8e01dca41002 313 plen = 0;
donatien 0:8e01dca41002 314 while (p != NULL)
donatien 0:8e01dca41002 315 {
donatien 0:8e01dca41002 316 base = plen;
donatien 0:8e01dca41002 317 plen += p->len;
donatien 0:8e01dca41002 318 if (ofs < plen)
donatien 0:8e01dca41002 319 {
donatien 0:8e01dca41002 320 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 321 msg_ptr += ofs - base;
donatien 0:8e01dca41002 322
donatien 0:8e01dca41002 323 if (octets_needed == 5)
donatien 0:8e01dca41002 324 {
donatien 0:8e01dca41002 325 /* not enough bits in 'value' add leading 0x00 */
donatien 0:8e01dca41002 326 octets_needed--;
donatien 0:8e01dca41002 327 *msg_ptr = 0x00;
donatien 0:8e01dca41002 328 ofs += 1;
donatien 0:8e01dca41002 329 if (ofs >= plen)
donatien 0:8e01dca41002 330 {
donatien 0:8e01dca41002 331 /* next octet in next pbuf */
donatien 0:8e01dca41002 332 p = p->next;
donatien 0:8e01dca41002 333 if (p == NULL) { return ERR_ARG; }
donatien 0:8e01dca41002 334 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 335 plen += p->len;
donatien 0:8e01dca41002 336 }
donatien 0:8e01dca41002 337 else
donatien 0:8e01dca41002 338 {
donatien 0:8e01dca41002 339 /* next octet in same pbuf */
donatien 0:8e01dca41002 340 msg_ptr++;
donatien 0:8e01dca41002 341 }
donatien 0:8e01dca41002 342 }
donatien 0:8e01dca41002 343 while (octets_needed > 1)
donatien 0:8e01dca41002 344 {
donatien 0:8e01dca41002 345 octets_needed--;
donatien 0:8e01dca41002 346 *msg_ptr = (u8_t)(value >> (octets_needed << 3));
donatien 0:8e01dca41002 347 ofs += 1;
donatien 0:8e01dca41002 348 if (ofs >= plen)
donatien 0:8e01dca41002 349 {
donatien 0:8e01dca41002 350 /* next octet in next pbuf */
donatien 0:8e01dca41002 351 p = p->next;
donatien 0:8e01dca41002 352 if (p == NULL) { return ERR_ARG; }
donatien 0:8e01dca41002 353 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 354 plen += p->len;
donatien 0:8e01dca41002 355 }
donatien 0:8e01dca41002 356 else
donatien 0:8e01dca41002 357 {
donatien 0:8e01dca41002 358 /* next octet in same pbuf */
donatien 0:8e01dca41002 359 msg_ptr++;
donatien 0:8e01dca41002 360 }
donatien 0:8e01dca41002 361 }
donatien 0:8e01dca41002 362 /* (only) one least significant octet */
donatien 0:8e01dca41002 363 *msg_ptr = (u8_t)value;
donatien 0:8e01dca41002 364 return ERR_OK;
donatien 0:8e01dca41002 365 }
donatien 0:8e01dca41002 366 p = p->next;
donatien 0:8e01dca41002 367 }
donatien 0:8e01dca41002 368 /* p == NULL, ofs >= plen */
donatien 0:8e01dca41002 369 return ERR_ARG;
donatien 0:8e01dca41002 370 }
donatien 0:8e01dca41002 371
donatien 0:8e01dca41002 372 /**
donatien 0:8e01dca41002 373 * Encodes s32_t integer into a pbuf chained ASN1 msg.
donatien 0:8e01dca41002 374 *
donatien 0:8e01dca41002 375 * @param p points to output pbuf to encode value into
donatien 0:8e01dca41002 376 * @param ofs points to the offset within the pbuf chain
donatien 0:8e01dca41002 377 * @param octets_needed encoding length (from snmp_asn1_enc_s32t_cnt())
donatien 0:8e01dca41002 378 * @param value is the host order s32_t value to be encoded
donatien 0:8e01dca41002 379 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
donatien 0:8e01dca41002 380 *
donatien 0:8e01dca41002 381 * @see snmp_asn1_enc_s32t_cnt()
donatien 0:8e01dca41002 382 */
donatien 0:8e01dca41002 383 err_t
donatien 0:8e01dca41002 384 snmp_asn1_enc_s32t(struct pbuf *p, u16_t ofs, u16_t octets_needed, s32_t value)
donatien 0:8e01dca41002 385 {
donatien 0:8e01dca41002 386 u16_t plen, base;
donatien 0:8e01dca41002 387 u8_t *msg_ptr;
donatien 0:8e01dca41002 388
donatien 0:8e01dca41002 389 plen = 0;
donatien 0:8e01dca41002 390 while (p != NULL)
donatien 0:8e01dca41002 391 {
donatien 0:8e01dca41002 392 base = plen;
donatien 0:8e01dca41002 393 plen += p->len;
donatien 0:8e01dca41002 394 if (ofs < plen)
donatien 0:8e01dca41002 395 {
donatien 0:8e01dca41002 396 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 397 msg_ptr += ofs - base;
donatien 0:8e01dca41002 398
donatien 0:8e01dca41002 399 while (octets_needed > 1)
donatien 0:8e01dca41002 400 {
donatien 0:8e01dca41002 401 octets_needed--;
donatien 0:8e01dca41002 402 *msg_ptr = (u8_t)(value >> (octets_needed << 3));
donatien 0:8e01dca41002 403 ofs += 1;
donatien 0:8e01dca41002 404 if (ofs >= plen)
donatien 0:8e01dca41002 405 {
donatien 0:8e01dca41002 406 /* next octet in next pbuf */
donatien 0:8e01dca41002 407 p = p->next;
donatien 0:8e01dca41002 408 if (p == NULL) { return ERR_ARG; }
donatien 0:8e01dca41002 409 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 410 plen += p->len;
donatien 0:8e01dca41002 411 }
donatien 0:8e01dca41002 412 else
donatien 0:8e01dca41002 413 {
donatien 0:8e01dca41002 414 /* next octet in same pbuf */
donatien 0:8e01dca41002 415 msg_ptr++;
donatien 0:8e01dca41002 416 }
donatien 0:8e01dca41002 417 }
donatien 0:8e01dca41002 418 /* (only) one least significant octet */
donatien 0:8e01dca41002 419 *msg_ptr = (u8_t)value;
donatien 0:8e01dca41002 420 return ERR_OK;
donatien 0:8e01dca41002 421 }
donatien 0:8e01dca41002 422 p = p->next;
donatien 0:8e01dca41002 423 }
donatien 0:8e01dca41002 424 /* p == NULL, ofs >= plen */
donatien 0:8e01dca41002 425 return ERR_ARG;
donatien 0:8e01dca41002 426 }
donatien 0:8e01dca41002 427
donatien 0:8e01dca41002 428 /**
donatien 0:8e01dca41002 429 * Encodes object identifier into a pbuf chained ASN1 msg.
donatien 0:8e01dca41002 430 *
donatien 0:8e01dca41002 431 * @param p points to output pbuf to encode oid into
donatien 0:8e01dca41002 432 * @param ofs points to the offset within the pbuf chain
donatien 0:8e01dca41002 433 * @param ident_len object identifier array length
donatien 0:8e01dca41002 434 * @param ident points to object identifier array
donatien 0:8e01dca41002 435 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
donatien 0:8e01dca41002 436 */
donatien 0:8e01dca41002 437 err_t
donatien 0:8e01dca41002 438 snmp_asn1_enc_oid(struct pbuf *p, u16_t ofs, u8_t ident_len, s32_t *ident)
donatien 0:8e01dca41002 439 {
donatien 0:8e01dca41002 440 u16_t plen, base;
donatien 0:8e01dca41002 441 u8_t *msg_ptr;
donatien 0:8e01dca41002 442
donatien 0:8e01dca41002 443 plen = 0;
donatien 0:8e01dca41002 444 while (p != NULL)
donatien 0:8e01dca41002 445 {
donatien 0:8e01dca41002 446 base = plen;
donatien 0:8e01dca41002 447 plen += p->len;
donatien 0:8e01dca41002 448 if (ofs < plen)
donatien 0:8e01dca41002 449 {
donatien 0:8e01dca41002 450 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 451 msg_ptr += ofs - base;
donatien 0:8e01dca41002 452
donatien 0:8e01dca41002 453 if (ident_len > 1)
donatien 0:8e01dca41002 454 {
donatien 0:8e01dca41002 455 if ((ident[0] == 1) && (ident[1] == 3))
donatien 0:8e01dca41002 456 {
donatien 0:8e01dca41002 457 /* compressed (most common) prefix .iso.org */
donatien 0:8e01dca41002 458 *msg_ptr = 0x2b;
donatien 0:8e01dca41002 459 }
donatien 0:8e01dca41002 460 else
donatien 0:8e01dca41002 461 {
donatien 0:8e01dca41002 462 /* calculate prefix */
donatien 0:8e01dca41002 463 *msg_ptr = (u8_t)((ident[0] * 40) + ident[1]);
donatien 0:8e01dca41002 464 }
donatien 0:8e01dca41002 465 ofs += 1;
donatien 0:8e01dca41002 466 if (ofs >= plen)
donatien 0:8e01dca41002 467 {
donatien 0:8e01dca41002 468 /* next octet in next pbuf */
donatien 0:8e01dca41002 469 p = p->next;
donatien 0:8e01dca41002 470 if (p == NULL) { return ERR_ARG; }
donatien 0:8e01dca41002 471 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 472 plen += p->len;
donatien 0:8e01dca41002 473 }
donatien 0:8e01dca41002 474 else
donatien 0:8e01dca41002 475 {
donatien 0:8e01dca41002 476 /* next octet in same pbuf */
donatien 0:8e01dca41002 477 msg_ptr++;
donatien 0:8e01dca41002 478 }
donatien 0:8e01dca41002 479 ident_len -= 2;
donatien 0:8e01dca41002 480 ident += 2;
donatien 0:8e01dca41002 481 }
donatien 0:8e01dca41002 482 else
donatien 0:8e01dca41002 483 {
donatien 0:8e01dca41002 484 /* @bug: allow empty varbinds for symmetry (we must decode them for getnext), allow partial compression?? */
donatien 0:8e01dca41002 485 /* ident_len <= 1, at least we need zeroDotZero (0.0) (ident_len == 2) */
donatien 0:8e01dca41002 486 return ERR_ARG;
donatien 0:8e01dca41002 487 }
donatien 0:8e01dca41002 488 while (ident_len > 0)
donatien 0:8e01dca41002 489 {
donatien 0:8e01dca41002 490 s32_t sub_id;
donatien 0:8e01dca41002 491 u8_t shift, tail;
donatien 0:8e01dca41002 492
donatien 0:8e01dca41002 493 ident_len--;
donatien 0:8e01dca41002 494 sub_id = *ident;
donatien 0:8e01dca41002 495 tail = 0;
donatien 0:8e01dca41002 496 shift = 28;
donatien 0:8e01dca41002 497 while(shift > 0)
donatien 0:8e01dca41002 498 {
donatien 0:8e01dca41002 499 u8_t code;
donatien 0:8e01dca41002 500
donatien 0:8e01dca41002 501 code = (u8_t)(sub_id >> shift);
donatien 0:8e01dca41002 502 if ((code != 0) || (tail != 0))
donatien 0:8e01dca41002 503 {
donatien 0:8e01dca41002 504 tail = 1;
donatien 0:8e01dca41002 505 *msg_ptr = code | 0x80;
donatien 0:8e01dca41002 506 ofs += 1;
donatien 0:8e01dca41002 507 if (ofs >= plen)
donatien 0:8e01dca41002 508 {
donatien 0:8e01dca41002 509 /* next octet in next pbuf */
donatien 0:8e01dca41002 510 p = p->next;
donatien 0:8e01dca41002 511 if (p == NULL) { return ERR_ARG; }
donatien 0:8e01dca41002 512 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 513 plen += p->len;
donatien 0:8e01dca41002 514 }
donatien 0:8e01dca41002 515 else
donatien 0:8e01dca41002 516 {
donatien 0:8e01dca41002 517 /* next octet in same pbuf */
donatien 0:8e01dca41002 518 msg_ptr++;
donatien 0:8e01dca41002 519 }
donatien 0:8e01dca41002 520 }
donatien 0:8e01dca41002 521 shift -= 7;
donatien 0:8e01dca41002 522 }
donatien 0:8e01dca41002 523 *msg_ptr = (u8_t)sub_id & 0x7F;
donatien 0:8e01dca41002 524 if (ident_len > 0)
donatien 0:8e01dca41002 525 {
donatien 0:8e01dca41002 526 ofs += 1;
donatien 0:8e01dca41002 527 if (ofs >= plen)
donatien 0:8e01dca41002 528 {
donatien 0:8e01dca41002 529 /* next octet in next pbuf */
donatien 0:8e01dca41002 530 p = p->next;
donatien 0:8e01dca41002 531 if (p == NULL) { return ERR_ARG; }
donatien 0:8e01dca41002 532 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 533 plen += p->len;
donatien 0:8e01dca41002 534 }
donatien 0:8e01dca41002 535 else
donatien 0:8e01dca41002 536 {
donatien 0:8e01dca41002 537 /* next octet in same pbuf */
donatien 0:8e01dca41002 538 msg_ptr++;
donatien 0:8e01dca41002 539 }
donatien 0:8e01dca41002 540 }
donatien 0:8e01dca41002 541 /* proceed to next sub-identifier */
donatien 0:8e01dca41002 542 ident++;
donatien 0:8e01dca41002 543 }
donatien 0:8e01dca41002 544 return ERR_OK;
donatien 0:8e01dca41002 545 }
donatien 0:8e01dca41002 546 p = p->next;
donatien 0:8e01dca41002 547 }
donatien 0:8e01dca41002 548 /* p == NULL, ofs >= plen */
donatien 0:8e01dca41002 549 return ERR_ARG;
donatien 0:8e01dca41002 550 }
donatien 0:8e01dca41002 551
donatien 0:8e01dca41002 552 /**
donatien 0:8e01dca41002 553 * Encodes raw data (octet string, opaque) into a pbuf chained ASN1 msg.
donatien 0:8e01dca41002 554 *
donatien 0:8e01dca41002 555 * @param p points to output pbuf to encode raw data into
donatien 0:8e01dca41002 556 * @param ofs points to the offset within the pbuf chain
donatien 0:8e01dca41002 557 * @param raw_len raw data length
donatien 0:8e01dca41002 558 * @param raw points raw data
donatien 0:8e01dca41002 559 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
donatien 0:8e01dca41002 560 */
donatien 0:8e01dca41002 561 err_t
donatien 0:8e01dca41002 562 snmp_asn1_enc_raw(struct pbuf *p, u16_t ofs, u16_t raw_len, u8_t *raw)
donatien 0:8e01dca41002 563 {
donatien 0:8e01dca41002 564 u16_t plen, base;
donatien 0:8e01dca41002 565 u8_t *msg_ptr;
donatien 0:8e01dca41002 566
donatien 0:8e01dca41002 567 plen = 0;
donatien 0:8e01dca41002 568 while (p != NULL)
donatien 0:8e01dca41002 569 {
donatien 0:8e01dca41002 570 base = plen;
donatien 0:8e01dca41002 571 plen += p->len;
donatien 0:8e01dca41002 572 if (ofs < plen)
donatien 0:8e01dca41002 573 {
donatien 0:8e01dca41002 574 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 575 msg_ptr += ofs - base;
donatien 0:8e01dca41002 576
donatien 0:8e01dca41002 577 while (raw_len > 1)
donatien 0:8e01dca41002 578 {
donatien 0:8e01dca41002 579 /* copy raw_len - 1 octets */
donatien 0:8e01dca41002 580 raw_len--;
donatien 0:8e01dca41002 581 *msg_ptr = *raw;
donatien 0:8e01dca41002 582 raw++;
donatien 0:8e01dca41002 583 ofs += 1;
donatien 0:8e01dca41002 584 if (ofs >= plen)
donatien 0:8e01dca41002 585 {
donatien 0:8e01dca41002 586 /* next octet in next pbuf */
donatien 0:8e01dca41002 587 p = p->next;
donatien 0:8e01dca41002 588 if (p == NULL) { return ERR_ARG; }
donatien 0:8e01dca41002 589 msg_ptr = (u8_t*)p->payload;
donatien 0:8e01dca41002 590 plen += p->len;
donatien 0:8e01dca41002 591 }
donatien 0:8e01dca41002 592 else
donatien 0:8e01dca41002 593 {
donatien 0:8e01dca41002 594 /* next octet in same pbuf */
donatien 0:8e01dca41002 595 msg_ptr++;
donatien 0:8e01dca41002 596 }
donatien 0:8e01dca41002 597 }
donatien 0:8e01dca41002 598 if (raw_len > 0)
donatien 0:8e01dca41002 599 {
donatien 0:8e01dca41002 600 /* copy last or single octet */
donatien 0:8e01dca41002 601 *msg_ptr = *raw;
donatien 0:8e01dca41002 602 }
donatien 0:8e01dca41002 603 return ERR_OK;
donatien 0:8e01dca41002 604 }
donatien 0:8e01dca41002 605 p = p->next;
donatien 0:8e01dca41002 606 }
donatien 0:8e01dca41002 607 /* p == NULL, ofs >= plen */
donatien 0:8e01dca41002 608 return ERR_ARG;
donatien 0:8e01dca41002 609 }
donatien 0:8e01dca41002 610
donatien 0:8e01dca41002 611 #endif /* LWIP_SNMP */