Donatien Garnier
ZG2100 Network interface source
lwip/core/snmp/asn1_dec.c@0:b802fc31f1db, 2010-07-09 (annotated)
- Committer:
- donatien
- Date:
- Fri Jul 09 15:37:23 2010 +0000
- Revision:
- 0:b802fc31f1db
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| donatien | 0:b802fc31f1db | 1 | /** |
| donatien | 0:b802fc31f1db | 2 | * @file |
| donatien | 0:b802fc31f1db | 3 | * Abstract Syntax Notation One (ISO 8824, 8825) decoding |
| donatien | 0:b802fc31f1db | 4 | * |
| donatien | 0:b802fc31f1db | 5 | * @todo not optimised (yet), favor correctness over speed, favor speed over size |
| donatien | 0:b802fc31f1db | 6 | */ |
| donatien | 0:b802fc31f1db | 7 | |
| donatien | 0:b802fc31f1db | 8 | /* |
| donatien | 0:b802fc31f1db | 9 | * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands. |
| donatien | 0:b802fc31f1db | 10 | * All rights reserved. |
| donatien | 0:b802fc31f1db | 11 | * |
| donatien | 0:b802fc31f1db | 12 | * Redistribution and use in source and binary forms, with or without modification, |
| donatien | 0:b802fc31f1db | 13 | * are permitted provided that the following conditions are met: |
| donatien | 0:b802fc31f1db | 14 | * |
| donatien | 0:b802fc31f1db | 15 | * 1. Redistributions of source code must retain the above copyright notice, |
| donatien | 0:b802fc31f1db | 16 | * this list of conditions and the following disclaimer. |
| donatien | 0:b802fc31f1db | 17 | * 2. Redistributions in binary form must reproduce the above copyright notice, |
| donatien | 0:b802fc31f1db | 18 | * this list of conditions and the following disclaimer in the documentation |
| donatien | 0:b802fc31f1db | 19 | * and/or other materials provided with the distribution. |
| donatien | 0:b802fc31f1db | 20 | * 3. The name of the author may not be used to endorse or promote products |
| donatien | 0:b802fc31f1db | 21 | * derived from this software without specific prior written permission. |
| donatien | 0:b802fc31f1db | 22 | * |
| donatien | 0:b802fc31f1db | 23 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| donatien | 0:b802fc31f1db | 24 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| donatien | 0:b802fc31f1db | 25 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT |
| donatien | 0:b802fc31f1db | 26 | * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| donatien | 0:b802fc31f1db | 27 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT |
| donatien | 0:b802fc31f1db | 28 | * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| donatien | 0:b802fc31f1db | 29 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| donatien | 0:b802fc31f1db | 30 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING |
| donatien | 0:b802fc31f1db | 31 | * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY |
| donatien | 0:b802fc31f1db | 32 | * OF SUCH DAMAGE. |
| donatien | 0:b802fc31f1db | 33 | * |
| donatien | 0:b802fc31f1db | 34 | * Author: Christiaan Simons <christiaan.simons@axon.tv> |
| donatien | 0:b802fc31f1db | 35 | */ |
| donatien | 0:b802fc31f1db | 36 | |
| donatien | 0:b802fc31f1db | 37 | #include "lwip/opt.h" |
| donatien | 0:b802fc31f1db | 38 | |
| donatien | 0:b802fc31f1db | 39 | #if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */ |
| donatien | 0:b802fc31f1db | 40 | |
| donatien | 0:b802fc31f1db | 41 | #include "lwip/snmp_asn1.h" |
| donatien | 0:b802fc31f1db | 42 | |
| donatien | 0:b802fc31f1db | 43 | /** |
| donatien | 0:b802fc31f1db | 44 | * Retrieves type field from incoming pbuf chain. |
| donatien | 0:b802fc31f1db | 45 | * |
| donatien | 0:b802fc31f1db | 46 | * @param p points to a pbuf holding an ASN1 coded type field |
| donatien | 0:b802fc31f1db | 47 | * @param ofs points to the offset within the pbuf chain of the ASN1 coded type field |
| donatien | 0:b802fc31f1db | 48 | * @param type return ASN1 type |
| donatien | 0:b802fc31f1db | 49 | * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode |
| donatien | 0:b802fc31f1db | 50 | */ |
| donatien | 0:b802fc31f1db | 51 | err_t |
| donatien | 0:b802fc31f1db | 52 | snmp_asn1_dec_type(struct pbuf *p, u16_t ofs, u8_t *type) |
| donatien | 0:b802fc31f1db | 53 | { |
| donatien | 0:b802fc31f1db | 54 | u16_t plen, base; |
| donatien | 0:b802fc31f1db | 55 | u8_t *msg_ptr; |
| donatien | 0:b802fc31f1db | 56 | |
| donatien | 0:b802fc31f1db | 57 | plen = 0; |
| donatien | 0:b802fc31f1db | 58 | while (p != NULL) |
| donatien | 0:b802fc31f1db | 59 | { |
| donatien | 0:b802fc31f1db | 60 | base = plen; |
| donatien | 0:b802fc31f1db | 61 | plen += p->len; |
| donatien | 0:b802fc31f1db | 62 | if (ofs < plen) |
| donatien | 0:b802fc31f1db | 63 | { |
| donatien | 0:b802fc31f1db | 64 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 65 | msg_ptr += ofs - base; |
| donatien | 0:b802fc31f1db | 66 | *type = *msg_ptr; |
| donatien | 0:b802fc31f1db | 67 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 68 | } |
| donatien | 0:b802fc31f1db | 69 | p = p->next; |
| donatien | 0:b802fc31f1db | 70 | } |
| donatien | 0:b802fc31f1db | 71 | /* p == NULL, ofs >= plen */ |
| donatien | 0:b802fc31f1db | 72 | return ERR_ARG; |
| donatien | 0:b802fc31f1db | 73 | } |
| donatien | 0:b802fc31f1db | 74 | |
| donatien | 0:b802fc31f1db | 75 | /** |
| donatien | 0:b802fc31f1db | 76 | * Decodes length field from incoming pbuf chain into host length. |
| donatien | 0:b802fc31f1db | 77 | * |
| donatien | 0:b802fc31f1db | 78 | * @param p points to a pbuf holding an ASN1 coded length |
| donatien | 0:b802fc31f1db | 79 | * @param ofs points to the offset within the pbuf chain of the ASN1 coded length |
| donatien | 0:b802fc31f1db | 80 | * @param octets_used returns number of octets used by the length code |
| donatien | 0:b802fc31f1db | 81 | * @param length return host order length, upto 64k |
| donatien | 0:b802fc31f1db | 82 | * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode |
| donatien | 0:b802fc31f1db | 83 | */ |
| donatien | 0:b802fc31f1db | 84 | err_t |
| donatien | 0:b802fc31f1db | 85 | snmp_asn1_dec_length(struct pbuf *p, u16_t ofs, u8_t *octets_used, u16_t *length) |
| donatien | 0:b802fc31f1db | 86 | { |
| donatien | 0:b802fc31f1db | 87 | u16_t plen, base; |
| donatien | 0:b802fc31f1db | 88 | u8_t *msg_ptr; |
| donatien | 0:b802fc31f1db | 89 | |
| donatien | 0:b802fc31f1db | 90 | plen = 0; |
| donatien | 0:b802fc31f1db | 91 | while (p != NULL) |
| donatien | 0:b802fc31f1db | 92 | { |
| donatien | 0:b802fc31f1db | 93 | base = plen; |
| donatien | 0:b802fc31f1db | 94 | plen += p->len; |
| donatien | 0:b802fc31f1db | 95 | if (ofs < plen) |
| donatien | 0:b802fc31f1db | 96 | { |
| donatien | 0:b802fc31f1db | 97 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 98 | msg_ptr += ofs - base; |
| donatien | 0:b802fc31f1db | 99 | |
| donatien | 0:b802fc31f1db | 100 | if (*msg_ptr < 0x80) |
| donatien | 0:b802fc31f1db | 101 | { |
| donatien | 0:b802fc31f1db | 102 | /* primitive definite length format */ |
| donatien | 0:b802fc31f1db | 103 | *octets_used = 1; |
| donatien | 0:b802fc31f1db | 104 | *length = *msg_ptr; |
| donatien | 0:b802fc31f1db | 105 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 106 | } |
| donatien | 0:b802fc31f1db | 107 | else if (*msg_ptr == 0x80) |
| donatien | 0:b802fc31f1db | 108 | { |
| donatien | 0:b802fc31f1db | 109 | /* constructed indefinite length format, termination with two zero octets */ |
| donatien | 0:b802fc31f1db | 110 | u8_t zeros; |
| donatien | 0:b802fc31f1db | 111 | u8_t i; |
| donatien | 0:b802fc31f1db | 112 | |
| donatien | 0:b802fc31f1db | 113 | *length = 0; |
| donatien | 0:b802fc31f1db | 114 | zeros = 0; |
| donatien | 0:b802fc31f1db | 115 | while (zeros != 2) |
| donatien | 0:b802fc31f1db | 116 | { |
| donatien | 0:b802fc31f1db | 117 | i = 2; |
| donatien | 0:b802fc31f1db | 118 | while (i > 0) |
| donatien | 0:b802fc31f1db | 119 | { |
| donatien | 0:b802fc31f1db | 120 | i--; |
| donatien | 0:b802fc31f1db | 121 | (*length) += 1; |
| donatien | 0:b802fc31f1db | 122 | ofs += 1; |
| donatien | 0:b802fc31f1db | 123 | if (ofs >= plen) |
| donatien | 0:b802fc31f1db | 124 | { |
| donatien | 0:b802fc31f1db | 125 | /* next octet in next pbuf */ |
| donatien | 0:b802fc31f1db | 126 | p = p->next; |
| donatien | 0:b802fc31f1db | 127 | if (p == NULL) { return ERR_ARG; } |
| donatien | 0:b802fc31f1db | 128 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 129 | plen += p->len; |
| donatien | 0:b802fc31f1db | 130 | } |
| donatien | 0:b802fc31f1db | 131 | else |
| donatien | 0:b802fc31f1db | 132 | { |
| donatien | 0:b802fc31f1db | 133 | /* next octet in same pbuf */ |
| donatien | 0:b802fc31f1db | 134 | msg_ptr++; |
| donatien | 0:b802fc31f1db | 135 | } |
| donatien | 0:b802fc31f1db | 136 | if (*msg_ptr == 0) |
| donatien | 0:b802fc31f1db | 137 | { |
| donatien | 0:b802fc31f1db | 138 | zeros++; |
| donatien | 0:b802fc31f1db | 139 | if (zeros == 2) |
| donatien | 0:b802fc31f1db | 140 | { |
| donatien | 0:b802fc31f1db | 141 | /* stop while (i > 0) */ |
| donatien | 0:b802fc31f1db | 142 | i = 0; |
| donatien | 0:b802fc31f1db | 143 | } |
| donatien | 0:b802fc31f1db | 144 | } |
| donatien | 0:b802fc31f1db | 145 | else |
| donatien | 0:b802fc31f1db | 146 | { |
| donatien | 0:b802fc31f1db | 147 | zeros = 0; |
| donatien | 0:b802fc31f1db | 148 | } |
| donatien | 0:b802fc31f1db | 149 | } |
| donatien | 0:b802fc31f1db | 150 | } |
| donatien | 0:b802fc31f1db | 151 | *octets_used = 1; |
| donatien | 0:b802fc31f1db | 152 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 153 | } |
| donatien | 0:b802fc31f1db | 154 | else if (*msg_ptr == 0x81) |
| donatien | 0:b802fc31f1db | 155 | { |
| donatien | 0:b802fc31f1db | 156 | /* constructed definite length format, one octet */ |
| donatien | 0:b802fc31f1db | 157 | ofs += 1; |
| donatien | 0:b802fc31f1db | 158 | if (ofs >= plen) |
| donatien | 0:b802fc31f1db | 159 | { |
| donatien | 0:b802fc31f1db | 160 | /* next octet in next pbuf */ |
| donatien | 0:b802fc31f1db | 161 | p = p->next; |
| donatien | 0:b802fc31f1db | 162 | if (p == NULL) { return ERR_ARG; } |
| donatien | 0:b802fc31f1db | 163 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 164 | } |
| donatien | 0:b802fc31f1db | 165 | else |
| donatien | 0:b802fc31f1db | 166 | { |
| donatien | 0:b802fc31f1db | 167 | /* next octet in same pbuf */ |
| donatien | 0:b802fc31f1db | 168 | msg_ptr++; |
| donatien | 0:b802fc31f1db | 169 | } |
| donatien | 0:b802fc31f1db | 170 | *length = *msg_ptr; |
| donatien | 0:b802fc31f1db | 171 | *octets_used = 2; |
| donatien | 0:b802fc31f1db | 172 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 173 | } |
| donatien | 0:b802fc31f1db | 174 | else if (*msg_ptr == 0x82) |
| donatien | 0:b802fc31f1db | 175 | { |
| donatien | 0:b802fc31f1db | 176 | u8_t i; |
| donatien | 0:b802fc31f1db | 177 | |
| donatien | 0:b802fc31f1db | 178 | /* constructed definite length format, two octets */ |
| donatien | 0:b802fc31f1db | 179 | i = 2; |
| donatien | 0:b802fc31f1db | 180 | while (i > 0) |
| donatien | 0:b802fc31f1db | 181 | { |
| donatien | 0:b802fc31f1db | 182 | i--; |
| donatien | 0:b802fc31f1db | 183 | ofs += 1; |
| donatien | 0:b802fc31f1db | 184 | if (ofs >= plen) |
| donatien | 0:b802fc31f1db | 185 | { |
| donatien | 0:b802fc31f1db | 186 | /* next octet in next pbuf */ |
| donatien | 0:b802fc31f1db | 187 | p = p->next; |
| donatien | 0:b802fc31f1db | 188 | if (p == NULL) { return ERR_ARG; } |
| donatien | 0:b802fc31f1db | 189 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 190 | plen += p->len; |
| donatien | 0:b802fc31f1db | 191 | } |
| donatien | 0:b802fc31f1db | 192 | else |
| donatien | 0:b802fc31f1db | 193 | { |
| donatien | 0:b802fc31f1db | 194 | /* next octet in same pbuf */ |
| donatien | 0:b802fc31f1db | 195 | msg_ptr++; |
| donatien | 0:b802fc31f1db | 196 | } |
| donatien | 0:b802fc31f1db | 197 | if (i == 0) |
| donatien | 0:b802fc31f1db | 198 | { |
| donatien | 0:b802fc31f1db | 199 | /* least significant length octet */ |
| donatien | 0:b802fc31f1db | 200 | *length |= *msg_ptr; |
| donatien | 0:b802fc31f1db | 201 | } |
| donatien | 0:b802fc31f1db | 202 | else |
| donatien | 0:b802fc31f1db | 203 | { |
| donatien | 0:b802fc31f1db | 204 | /* most significant length octet */ |
| donatien | 0:b802fc31f1db | 205 | *length = (*msg_ptr) << 8; |
| donatien | 0:b802fc31f1db | 206 | } |
| donatien | 0:b802fc31f1db | 207 | } |
| donatien | 0:b802fc31f1db | 208 | *octets_used = 3; |
| donatien | 0:b802fc31f1db | 209 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 210 | } |
| donatien | 0:b802fc31f1db | 211 | else |
| donatien | 0:b802fc31f1db | 212 | { |
| donatien | 0:b802fc31f1db | 213 | /* constructed definite length format 3..127 octets, this is too big (>64k) */ |
| donatien | 0:b802fc31f1db | 214 | /** @todo: do we need to accept inefficient codings with many leading zero's? */ |
| donatien | 0:b802fc31f1db | 215 | *octets_used = 1 + ((*msg_ptr) & 0x7f); |
| donatien | 0:b802fc31f1db | 216 | return ERR_ARG; |
| donatien | 0:b802fc31f1db | 217 | } |
| donatien | 0:b802fc31f1db | 218 | } |
| donatien | 0:b802fc31f1db | 219 | p = p->next; |
| donatien | 0:b802fc31f1db | 220 | } |
| donatien | 0:b802fc31f1db | 221 | |
| donatien | 0:b802fc31f1db | 222 | /* p == NULL, ofs >= plen */ |
| donatien | 0:b802fc31f1db | 223 | return ERR_ARG; |
| donatien | 0:b802fc31f1db | 224 | } |
| donatien | 0:b802fc31f1db | 225 | |
| donatien | 0:b802fc31f1db | 226 | /** |
| donatien | 0:b802fc31f1db | 227 | * Decodes positive integer (counter, gauge, timeticks) into u32_t. |
| donatien | 0:b802fc31f1db | 228 | * |
| donatien | 0:b802fc31f1db | 229 | * @param p points to a pbuf holding an ASN1 coded integer |
| donatien | 0:b802fc31f1db | 230 | * @param ofs points to the offset within the pbuf chain of the ASN1 coded integer |
| donatien | 0:b802fc31f1db | 231 | * @param len length of the coded integer field |
| donatien | 0:b802fc31f1db | 232 | * @param value return host order integer |
| donatien | 0:b802fc31f1db | 233 | * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode |
| donatien | 0:b802fc31f1db | 234 | * |
| donatien | 0:b802fc31f1db | 235 | * @note ASN coded integers are _always_ signed. E.g. +0xFFFF is coded |
| donatien | 0:b802fc31f1db | 236 | * as 0x00,0xFF,0xFF. Note the leading sign octet. A positive value |
| donatien | 0:b802fc31f1db | 237 | * of 0xFFFFFFFF is preceded with 0x00 and the length is 5 octets!! |
| donatien | 0:b802fc31f1db | 238 | */ |
| donatien | 0:b802fc31f1db | 239 | err_t |
| donatien | 0:b802fc31f1db | 240 | snmp_asn1_dec_u32t(struct pbuf *p, u16_t ofs, u16_t len, u32_t *value) |
| donatien | 0:b802fc31f1db | 241 | { |
| donatien | 0:b802fc31f1db | 242 | u16_t plen, base; |
| donatien | 0:b802fc31f1db | 243 | u8_t *msg_ptr; |
| donatien | 0:b802fc31f1db | 244 | |
| donatien | 0:b802fc31f1db | 245 | plen = 0; |
| donatien | 0:b802fc31f1db | 246 | while (p != NULL) |
| donatien | 0:b802fc31f1db | 247 | { |
| donatien | 0:b802fc31f1db | 248 | base = plen; |
| donatien | 0:b802fc31f1db | 249 | plen += p->len; |
| donatien | 0:b802fc31f1db | 250 | if (ofs < plen) |
| donatien | 0:b802fc31f1db | 251 | { |
| donatien | 0:b802fc31f1db | 252 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 253 | msg_ptr += ofs - base; |
| donatien | 0:b802fc31f1db | 254 | if ((len > 0) && (len < 6)) |
| donatien | 0:b802fc31f1db | 255 | { |
| donatien | 0:b802fc31f1db | 256 | /* start from zero */ |
| donatien | 0:b802fc31f1db | 257 | *value = 0; |
| donatien | 0:b802fc31f1db | 258 | if (*msg_ptr & 0x80) |
| donatien | 0:b802fc31f1db | 259 | { |
| donatien | 0:b802fc31f1db | 260 | /* negative, expecting zero sign bit! */ |
| donatien | 0:b802fc31f1db | 261 | return ERR_ARG; |
| donatien | 0:b802fc31f1db | 262 | } |
| donatien | 0:b802fc31f1db | 263 | else |
| donatien | 0:b802fc31f1db | 264 | { |
| donatien | 0:b802fc31f1db | 265 | /* positive */ |
| donatien | 0:b802fc31f1db | 266 | if ((len > 1) && (*msg_ptr == 0)) |
| donatien | 0:b802fc31f1db | 267 | { |
| donatien | 0:b802fc31f1db | 268 | /* skip leading "sign byte" octet 0x00 */ |
| donatien | 0:b802fc31f1db | 269 | len--; |
| donatien | 0:b802fc31f1db | 270 | ofs += 1; |
| donatien | 0:b802fc31f1db | 271 | if (ofs >= plen) |
| donatien | 0:b802fc31f1db | 272 | { |
| donatien | 0:b802fc31f1db | 273 | /* next octet in next pbuf */ |
| donatien | 0:b802fc31f1db | 274 | p = p->next; |
| donatien | 0:b802fc31f1db | 275 | if (p == NULL) { return ERR_ARG; } |
| donatien | 0:b802fc31f1db | 276 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 277 | plen += p->len; |
| donatien | 0:b802fc31f1db | 278 | } |
| donatien | 0:b802fc31f1db | 279 | else |
| donatien | 0:b802fc31f1db | 280 | { |
| donatien | 0:b802fc31f1db | 281 | /* next octet in same pbuf */ |
| donatien | 0:b802fc31f1db | 282 | msg_ptr++; |
| donatien | 0:b802fc31f1db | 283 | } |
| donatien | 0:b802fc31f1db | 284 | } |
| donatien | 0:b802fc31f1db | 285 | } |
| donatien | 0:b802fc31f1db | 286 | /* OR octets with value */ |
| donatien | 0:b802fc31f1db | 287 | while (len > 1) |
| donatien | 0:b802fc31f1db | 288 | { |
| donatien | 0:b802fc31f1db | 289 | len--; |
| donatien | 0:b802fc31f1db | 290 | *value |= *msg_ptr; |
| donatien | 0:b802fc31f1db | 291 | *value <<= 8; |
| donatien | 0:b802fc31f1db | 292 | ofs += 1; |
| donatien | 0:b802fc31f1db | 293 | if (ofs >= plen) |
| donatien | 0:b802fc31f1db | 294 | { |
| donatien | 0:b802fc31f1db | 295 | /* next octet in next pbuf */ |
| donatien | 0:b802fc31f1db | 296 | p = p->next; |
| donatien | 0:b802fc31f1db | 297 | if (p == NULL) { return ERR_ARG; } |
| donatien | 0:b802fc31f1db | 298 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 299 | plen += p->len; |
| donatien | 0:b802fc31f1db | 300 | } |
| donatien | 0:b802fc31f1db | 301 | else |
| donatien | 0:b802fc31f1db | 302 | { |
| donatien | 0:b802fc31f1db | 303 | /* next octet in same pbuf */ |
| donatien | 0:b802fc31f1db | 304 | msg_ptr++; |
| donatien | 0:b802fc31f1db | 305 | } |
| donatien | 0:b802fc31f1db | 306 | } |
| donatien | 0:b802fc31f1db | 307 | *value |= *msg_ptr; |
| donatien | 0:b802fc31f1db | 308 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 309 | } |
| donatien | 0:b802fc31f1db | 310 | else |
| donatien | 0:b802fc31f1db | 311 | { |
| donatien | 0:b802fc31f1db | 312 | return ERR_ARG; |
| donatien | 0:b802fc31f1db | 313 | } |
| donatien | 0:b802fc31f1db | 314 | } |
| donatien | 0:b802fc31f1db | 315 | p = p->next; |
| donatien | 0:b802fc31f1db | 316 | } |
| donatien | 0:b802fc31f1db | 317 | /* p == NULL, ofs >= plen */ |
| donatien | 0:b802fc31f1db | 318 | return ERR_ARG; |
| donatien | 0:b802fc31f1db | 319 | } |
| donatien | 0:b802fc31f1db | 320 | |
| donatien | 0:b802fc31f1db | 321 | /** |
| donatien | 0:b802fc31f1db | 322 | * Decodes integer into s32_t. |
| donatien | 0:b802fc31f1db | 323 | * |
| donatien | 0:b802fc31f1db | 324 | * @param p points to a pbuf holding an ASN1 coded integer |
| donatien | 0:b802fc31f1db | 325 | * @param ofs points to the offset within the pbuf chain of the ASN1 coded integer |
| donatien | 0:b802fc31f1db | 326 | * @param len length of the coded integer field |
| donatien | 0:b802fc31f1db | 327 | * @param value return host order integer |
| donatien | 0:b802fc31f1db | 328 | * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode |
| donatien | 0:b802fc31f1db | 329 | * |
| donatien | 0:b802fc31f1db | 330 | * @note ASN coded integers are _always_ signed! |
| donatien | 0:b802fc31f1db | 331 | */ |
| donatien | 0:b802fc31f1db | 332 | err_t |
| donatien | 0:b802fc31f1db | 333 | snmp_asn1_dec_s32t(struct pbuf *p, u16_t ofs, u16_t len, s32_t *value) |
| donatien | 0:b802fc31f1db | 334 | { |
| donatien | 0:b802fc31f1db | 335 | u16_t plen, base; |
| donatien | 0:b802fc31f1db | 336 | u8_t *msg_ptr; |
| donatien | 0:b802fc31f1db | 337 | #if BYTE_ORDER == LITTLE_ENDIAN |
| donatien | 0:b802fc31f1db | 338 | u8_t *lsb_ptr = (u8_t*)value; |
| donatien | 0:b802fc31f1db | 339 | #endif |
| donatien | 0:b802fc31f1db | 340 | #if BYTE_ORDER == BIG_ENDIAN |
| donatien | 0:b802fc31f1db | 341 | u8_t *lsb_ptr = (u8_t*)value + sizeof(s32_t) - 1; |
| donatien | 0:b802fc31f1db | 342 | #endif |
| donatien | 0:b802fc31f1db | 343 | u8_t sign; |
| donatien | 0:b802fc31f1db | 344 | |
| donatien | 0:b802fc31f1db | 345 | plen = 0; |
| donatien | 0:b802fc31f1db | 346 | while (p != NULL) |
| donatien | 0:b802fc31f1db | 347 | { |
| donatien | 0:b802fc31f1db | 348 | base = plen; |
| donatien | 0:b802fc31f1db | 349 | plen += p->len; |
| donatien | 0:b802fc31f1db | 350 | if (ofs < plen) |
| donatien | 0:b802fc31f1db | 351 | { |
| donatien | 0:b802fc31f1db | 352 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 353 | msg_ptr += ofs - base; |
| donatien | 0:b802fc31f1db | 354 | if ((len > 0) && (len < 5)) |
| donatien | 0:b802fc31f1db | 355 | { |
| donatien | 0:b802fc31f1db | 356 | if (*msg_ptr & 0x80) |
| donatien | 0:b802fc31f1db | 357 | { |
| donatien | 0:b802fc31f1db | 358 | /* negative, start from -1 */ |
| donatien | 0:b802fc31f1db | 359 | *value = -1; |
| donatien | 0:b802fc31f1db | 360 | sign = 1; |
| donatien | 0:b802fc31f1db | 361 | } |
| donatien | 0:b802fc31f1db | 362 | else |
| donatien | 0:b802fc31f1db | 363 | { |
| donatien | 0:b802fc31f1db | 364 | /* positive, start from 0 */ |
| donatien | 0:b802fc31f1db | 365 | *value = 0; |
| donatien | 0:b802fc31f1db | 366 | sign = 0; |
| donatien | 0:b802fc31f1db | 367 | } |
| donatien | 0:b802fc31f1db | 368 | /* OR/AND octets with value */ |
| donatien | 0:b802fc31f1db | 369 | while (len > 1) |
| donatien | 0:b802fc31f1db | 370 | { |
| donatien | 0:b802fc31f1db | 371 | len--; |
| donatien | 0:b802fc31f1db | 372 | if (sign) |
| donatien | 0:b802fc31f1db | 373 | { |
| donatien | 0:b802fc31f1db | 374 | *lsb_ptr &= *msg_ptr; |
| donatien | 0:b802fc31f1db | 375 | *value <<= 8; |
| donatien | 0:b802fc31f1db | 376 | *lsb_ptr |= 255; |
| donatien | 0:b802fc31f1db | 377 | } |
| donatien | 0:b802fc31f1db | 378 | else |
| donatien | 0:b802fc31f1db | 379 | { |
| donatien | 0:b802fc31f1db | 380 | *lsb_ptr |= *msg_ptr; |
| donatien | 0:b802fc31f1db | 381 | *value <<= 8; |
| donatien | 0:b802fc31f1db | 382 | } |
| donatien | 0:b802fc31f1db | 383 | ofs += 1; |
| donatien | 0:b802fc31f1db | 384 | if (ofs >= plen) |
| donatien | 0:b802fc31f1db | 385 | { |
| donatien | 0:b802fc31f1db | 386 | /* next octet in next pbuf */ |
| donatien | 0:b802fc31f1db | 387 | p = p->next; |
| donatien | 0:b802fc31f1db | 388 | if (p == NULL) { return ERR_ARG; } |
| donatien | 0:b802fc31f1db | 389 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 390 | plen += p->len; |
| donatien | 0:b802fc31f1db | 391 | } |
| donatien | 0:b802fc31f1db | 392 | else |
| donatien | 0:b802fc31f1db | 393 | { |
| donatien | 0:b802fc31f1db | 394 | /* next octet in same pbuf */ |
| donatien | 0:b802fc31f1db | 395 | msg_ptr++; |
| donatien | 0:b802fc31f1db | 396 | } |
| donatien | 0:b802fc31f1db | 397 | } |
| donatien | 0:b802fc31f1db | 398 | if (sign) |
| donatien | 0:b802fc31f1db | 399 | { |
| donatien | 0:b802fc31f1db | 400 | *lsb_ptr &= *msg_ptr; |
| donatien | 0:b802fc31f1db | 401 | } |
| donatien | 0:b802fc31f1db | 402 | else |
| donatien | 0:b802fc31f1db | 403 | { |
| donatien | 0:b802fc31f1db | 404 | *lsb_ptr |= *msg_ptr; |
| donatien | 0:b802fc31f1db | 405 | } |
| donatien | 0:b802fc31f1db | 406 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 407 | } |
| donatien | 0:b802fc31f1db | 408 | else |
| donatien | 0:b802fc31f1db | 409 | { |
| donatien | 0:b802fc31f1db | 410 | return ERR_ARG; |
| donatien | 0:b802fc31f1db | 411 | } |
| donatien | 0:b802fc31f1db | 412 | } |
| donatien | 0:b802fc31f1db | 413 | p = p->next; |
| donatien | 0:b802fc31f1db | 414 | } |
| donatien | 0:b802fc31f1db | 415 | /* p == NULL, ofs >= plen */ |
| donatien | 0:b802fc31f1db | 416 | return ERR_ARG; |
| donatien | 0:b802fc31f1db | 417 | } |
| donatien | 0:b802fc31f1db | 418 | |
| donatien | 0:b802fc31f1db | 419 | /** |
| donatien | 0:b802fc31f1db | 420 | * Decodes object identifier from incoming message into array of s32_t. |
| donatien | 0:b802fc31f1db | 421 | * |
| donatien | 0:b802fc31f1db | 422 | * @param p points to a pbuf holding an ASN1 coded object identifier |
| donatien | 0:b802fc31f1db | 423 | * @param ofs points to the offset within the pbuf chain of the ASN1 coded object identifier |
| donatien | 0:b802fc31f1db | 424 | * @param len length of the coded object identifier |
| donatien | 0:b802fc31f1db | 425 | * @param oid return object identifier struct |
| donatien | 0:b802fc31f1db | 426 | * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode |
| donatien | 0:b802fc31f1db | 427 | */ |
| donatien | 0:b802fc31f1db | 428 | err_t |
| donatien | 0:b802fc31f1db | 429 | snmp_asn1_dec_oid(struct pbuf *p, u16_t ofs, u16_t len, struct snmp_obj_id *oid) |
| donatien | 0:b802fc31f1db | 430 | { |
| donatien | 0:b802fc31f1db | 431 | u16_t plen, base; |
| donatien | 0:b802fc31f1db | 432 | u8_t *msg_ptr; |
| donatien | 0:b802fc31f1db | 433 | s32_t *oid_ptr; |
| donatien | 0:b802fc31f1db | 434 | |
| donatien | 0:b802fc31f1db | 435 | plen = 0; |
| donatien | 0:b802fc31f1db | 436 | while (p != NULL) |
| donatien | 0:b802fc31f1db | 437 | { |
| donatien | 0:b802fc31f1db | 438 | base = plen; |
| donatien | 0:b802fc31f1db | 439 | plen += p->len; |
| donatien | 0:b802fc31f1db | 440 | if (ofs < plen) |
| donatien | 0:b802fc31f1db | 441 | { |
| donatien | 0:b802fc31f1db | 442 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 443 | msg_ptr += ofs - base; |
| donatien | 0:b802fc31f1db | 444 | |
| donatien | 0:b802fc31f1db | 445 | oid->len = 0; |
| donatien | 0:b802fc31f1db | 446 | oid_ptr = &oid->id[0]; |
| donatien | 0:b802fc31f1db | 447 | if (len > 0) |
| donatien | 0:b802fc31f1db | 448 | { |
| donatien | 0:b802fc31f1db | 449 | /* first compressed octet */ |
| donatien | 0:b802fc31f1db | 450 | if (*msg_ptr == 0x2B) |
| donatien | 0:b802fc31f1db | 451 | { |
| donatien | 0:b802fc31f1db | 452 | /* (most) common case 1.3 (iso.org) */ |
| donatien | 0:b802fc31f1db | 453 | *oid_ptr = 1; |
| donatien | 0:b802fc31f1db | 454 | oid_ptr++; |
| donatien | 0:b802fc31f1db | 455 | *oid_ptr = 3; |
| donatien | 0:b802fc31f1db | 456 | oid_ptr++; |
| donatien | 0:b802fc31f1db | 457 | } |
| donatien | 0:b802fc31f1db | 458 | else if (*msg_ptr < 40) |
| donatien | 0:b802fc31f1db | 459 | { |
| donatien | 0:b802fc31f1db | 460 | *oid_ptr = 0; |
| donatien | 0:b802fc31f1db | 461 | oid_ptr++; |
| donatien | 0:b802fc31f1db | 462 | *oid_ptr = *msg_ptr; |
| donatien | 0:b802fc31f1db | 463 | oid_ptr++; |
| donatien | 0:b802fc31f1db | 464 | } |
| donatien | 0:b802fc31f1db | 465 | else if (*msg_ptr < 80) |
| donatien | 0:b802fc31f1db | 466 | { |
| donatien | 0:b802fc31f1db | 467 | *oid_ptr = 1; |
| donatien | 0:b802fc31f1db | 468 | oid_ptr++; |
| donatien | 0:b802fc31f1db | 469 | *oid_ptr = (*msg_ptr) - 40; |
| donatien | 0:b802fc31f1db | 470 | oid_ptr++; |
| donatien | 0:b802fc31f1db | 471 | } |
| donatien | 0:b802fc31f1db | 472 | else |
| donatien | 0:b802fc31f1db | 473 | { |
| donatien | 0:b802fc31f1db | 474 | *oid_ptr = 2; |
| donatien | 0:b802fc31f1db | 475 | oid_ptr++; |
| donatien | 0:b802fc31f1db | 476 | *oid_ptr = (*msg_ptr) - 80; |
| donatien | 0:b802fc31f1db | 477 | oid_ptr++; |
| donatien | 0:b802fc31f1db | 478 | } |
| donatien | 0:b802fc31f1db | 479 | oid->len = 2; |
| donatien | 0:b802fc31f1db | 480 | } |
| donatien | 0:b802fc31f1db | 481 | else |
| donatien | 0:b802fc31f1db | 482 | { |
| donatien | 0:b802fc31f1db | 483 | /* accepting zero length identifiers e.g. for |
| donatien | 0:b802fc31f1db | 484 | getnext operation. uncommon but valid */ |
| donatien | 0:b802fc31f1db | 485 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 486 | } |
| donatien | 0:b802fc31f1db | 487 | len--; |
| donatien | 0:b802fc31f1db | 488 | if (len > 0) |
| donatien | 0:b802fc31f1db | 489 | { |
| donatien | 0:b802fc31f1db | 490 | ofs += 1; |
| donatien | 0:b802fc31f1db | 491 | if (ofs >= plen) |
| donatien | 0:b802fc31f1db | 492 | { |
| donatien | 0:b802fc31f1db | 493 | /* next octet in next pbuf */ |
| donatien | 0:b802fc31f1db | 494 | p = p->next; |
| donatien | 0:b802fc31f1db | 495 | if (p == NULL) { return ERR_ARG; } |
| donatien | 0:b802fc31f1db | 496 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 497 | plen += p->len; |
| donatien | 0:b802fc31f1db | 498 | } |
| donatien | 0:b802fc31f1db | 499 | else |
| donatien | 0:b802fc31f1db | 500 | { |
| donatien | 0:b802fc31f1db | 501 | /* next octet in same pbuf */ |
| donatien | 0:b802fc31f1db | 502 | msg_ptr++; |
| donatien | 0:b802fc31f1db | 503 | } |
| donatien | 0:b802fc31f1db | 504 | } |
| donatien | 0:b802fc31f1db | 505 | while ((len > 0) && (oid->len < LWIP_SNMP_OBJ_ID_LEN)) |
| donatien | 0:b802fc31f1db | 506 | { |
| donatien | 0:b802fc31f1db | 507 | /* sub-identifier uses multiple octets */ |
| donatien | 0:b802fc31f1db | 508 | if (*msg_ptr & 0x80) |
| donatien | 0:b802fc31f1db | 509 | { |
| donatien | 0:b802fc31f1db | 510 | s32_t sub_id = 0; |
| donatien | 0:b802fc31f1db | 511 | |
| donatien | 0:b802fc31f1db | 512 | while ((*msg_ptr & 0x80) && (len > 1)) |
| donatien | 0:b802fc31f1db | 513 | { |
| donatien | 0:b802fc31f1db | 514 | len--; |
| donatien | 0:b802fc31f1db | 515 | sub_id = (sub_id << 7) + (*msg_ptr & ~0x80); |
| donatien | 0:b802fc31f1db | 516 | ofs += 1; |
| donatien | 0:b802fc31f1db | 517 | if (ofs >= plen) |
| donatien | 0:b802fc31f1db | 518 | { |
| donatien | 0:b802fc31f1db | 519 | /* next octet in next pbuf */ |
| donatien | 0:b802fc31f1db | 520 | p = p->next; |
| donatien | 0:b802fc31f1db | 521 | if (p == NULL) { return ERR_ARG; } |
| donatien | 0:b802fc31f1db | 522 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 523 | plen += p->len; |
| donatien | 0:b802fc31f1db | 524 | } |
| donatien | 0:b802fc31f1db | 525 | else |
| donatien | 0:b802fc31f1db | 526 | { |
| donatien | 0:b802fc31f1db | 527 | /* next octet in same pbuf */ |
| donatien | 0:b802fc31f1db | 528 | msg_ptr++; |
| donatien | 0:b802fc31f1db | 529 | } |
| donatien | 0:b802fc31f1db | 530 | } |
| donatien | 0:b802fc31f1db | 531 | if (!(*msg_ptr & 0x80) && (len > 0)) |
| donatien | 0:b802fc31f1db | 532 | { |
| donatien | 0:b802fc31f1db | 533 | /* last octet sub-identifier */ |
| donatien | 0:b802fc31f1db | 534 | len--; |
| donatien | 0:b802fc31f1db | 535 | sub_id = (sub_id << 7) + *msg_ptr; |
| donatien | 0:b802fc31f1db | 536 | *oid_ptr = sub_id; |
| donatien | 0:b802fc31f1db | 537 | } |
| donatien | 0:b802fc31f1db | 538 | } |
| donatien | 0:b802fc31f1db | 539 | else |
| donatien | 0:b802fc31f1db | 540 | { |
| donatien | 0:b802fc31f1db | 541 | /* !(*msg_ptr & 0x80) sub-identifier uses single octet */ |
| donatien | 0:b802fc31f1db | 542 | len--; |
| donatien | 0:b802fc31f1db | 543 | *oid_ptr = *msg_ptr; |
| donatien | 0:b802fc31f1db | 544 | } |
| donatien | 0:b802fc31f1db | 545 | if (len > 0) |
| donatien | 0:b802fc31f1db | 546 | { |
| donatien | 0:b802fc31f1db | 547 | /* remaining oid bytes available ... */ |
| donatien | 0:b802fc31f1db | 548 | ofs += 1; |
| donatien | 0:b802fc31f1db | 549 | if (ofs >= plen) |
| donatien | 0:b802fc31f1db | 550 | { |
| donatien | 0:b802fc31f1db | 551 | /* next octet in next pbuf */ |
| donatien | 0:b802fc31f1db | 552 | p = p->next; |
| donatien | 0:b802fc31f1db | 553 | if (p == NULL) { return ERR_ARG; } |
| donatien | 0:b802fc31f1db | 554 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 555 | plen += p->len; |
| donatien | 0:b802fc31f1db | 556 | } |
| donatien | 0:b802fc31f1db | 557 | else |
| donatien | 0:b802fc31f1db | 558 | { |
| donatien | 0:b802fc31f1db | 559 | /* next octet in same pbuf */ |
| donatien | 0:b802fc31f1db | 560 | msg_ptr++; |
| donatien | 0:b802fc31f1db | 561 | } |
| donatien | 0:b802fc31f1db | 562 | } |
| donatien | 0:b802fc31f1db | 563 | oid_ptr++; |
| donatien | 0:b802fc31f1db | 564 | oid->len++; |
| donatien | 0:b802fc31f1db | 565 | } |
| donatien | 0:b802fc31f1db | 566 | if (len == 0) |
| donatien | 0:b802fc31f1db | 567 | { |
| donatien | 0:b802fc31f1db | 568 | /* len == 0, end of oid */ |
| donatien | 0:b802fc31f1db | 569 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 570 | } |
| donatien | 0:b802fc31f1db | 571 | else |
| donatien | 0:b802fc31f1db | 572 | { |
| donatien | 0:b802fc31f1db | 573 | /* len > 0, oid->len == LWIP_SNMP_OBJ_ID_LEN or malformed encoding */ |
| donatien | 0:b802fc31f1db | 574 | return ERR_ARG; |
| donatien | 0:b802fc31f1db | 575 | } |
| donatien | 0:b802fc31f1db | 576 | |
| donatien | 0:b802fc31f1db | 577 | } |
| donatien | 0:b802fc31f1db | 578 | p = p->next; |
| donatien | 0:b802fc31f1db | 579 | } |
| donatien | 0:b802fc31f1db | 580 | /* p == NULL, ofs >= plen */ |
| donatien | 0:b802fc31f1db | 581 | return ERR_ARG; |
| donatien | 0:b802fc31f1db | 582 | } |
| donatien | 0:b802fc31f1db | 583 | |
| donatien | 0:b802fc31f1db | 584 | /** |
| donatien | 0:b802fc31f1db | 585 | * Decodes (copies) raw data (ip-addresses, octet strings, opaque encoding) |
| donatien | 0:b802fc31f1db | 586 | * from incoming message into array. |
| donatien | 0:b802fc31f1db | 587 | * |
| donatien | 0:b802fc31f1db | 588 | * @param p points to a pbuf holding an ASN1 coded raw data |
| donatien | 0:b802fc31f1db | 589 | * @param ofs points to the offset within the pbuf chain of the ASN1 coded raw data |
| donatien | 0:b802fc31f1db | 590 | * @param len length of the coded raw data (zero is valid, e.g. empty string!) |
| donatien | 0:b802fc31f1db | 591 | * @param raw_len length of the raw return value |
| donatien | 0:b802fc31f1db | 592 | * @param raw return raw bytes |
| donatien | 0:b802fc31f1db | 593 | * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode |
| donatien | 0:b802fc31f1db | 594 | */ |
| donatien | 0:b802fc31f1db | 595 | err_t |
| donatien | 0:b802fc31f1db | 596 | snmp_asn1_dec_raw(struct pbuf *p, u16_t ofs, u16_t len, u16_t raw_len, u8_t *raw) |
| donatien | 0:b802fc31f1db | 597 | { |
| donatien | 0:b802fc31f1db | 598 | u16_t plen, base; |
| donatien | 0:b802fc31f1db | 599 | u8_t *msg_ptr; |
| donatien | 0:b802fc31f1db | 600 | |
| donatien | 0:b802fc31f1db | 601 | if (len > 0) |
| donatien | 0:b802fc31f1db | 602 | { |
| donatien | 0:b802fc31f1db | 603 | plen = 0; |
| donatien | 0:b802fc31f1db | 604 | while (p != NULL) |
| donatien | 0:b802fc31f1db | 605 | { |
| donatien | 0:b802fc31f1db | 606 | base = plen; |
| donatien | 0:b802fc31f1db | 607 | plen += p->len; |
| donatien | 0:b802fc31f1db | 608 | if (ofs < plen) |
| donatien | 0:b802fc31f1db | 609 | { |
| donatien | 0:b802fc31f1db | 610 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 611 | msg_ptr += ofs - base; |
| donatien | 0:b802fc31f1db | 612 | if (raw_len >= len) |
| donatien | 0:b802fc31f1db | 613 | { |
| donatien | 0:b802fc31f1db | 614 | while (len > 1) |
| donatien | 0:b802fc31f1db | 615 | { |
| donatien | 0:b802fc31f1db | 616 | /* copy len - 1 octets */ |
| donatien | 0:b802fc31f1db | 617 | len--; |
| donatien | 0:b802fc31f1db | 618 | *raw = *msg_ptr; |
| donatien | 0:b802fc31f1db | 619 | raw++; |
| donatien | 0:b802fc31f1db | 620 | ofs += 1; |
| donatien | 0:b802fc31f1db | 621 | if (ofs >= plen) |
| donatien | 0:b802fc31f1db | 622 | { |
| donatien | 0:b802fc31f1db | 623 | /* next octet in next pbuf */ |
| donatien | 0:b802fc31f1db | 624 | p = p->next; |
| donatien | 0:b802fc31f1db | 625 | if (p == NULL) { return ERR_ARG; } |
| donatien | 0:b802fc31f1db | 626 | msg_ptr = (u8_t*)p->payload; |
| donatien | 0:b802fc31f1db | 627 | plen += p->len; |
| donatien | 0:b802fc31f1db | 628 | } |
| donatien | 0:b802fc31f1db | 629 | else |
| donatien | 0:b802fc31f1db | 630 | { |
| donatien | 0:b802fc31f1db | 631 | /* next octet in same pbuf */ |
| donatien | 0:b802fc31f1db | 632 | msg_ptr++; |
| donatien | 0:b802fc31f1db | 633 | } |
| donatien | 0:b802fc31f1db | 634 | } |
| donatien | 0:b802fc31f1db | 635 | /* copy last octet */ |
| donatien | 0:b802fc31f1db | 636 | *raw = *msg_ptr; |
| donatien | 0:b802fc31f1db | 637 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 638 | } |
| donatien | 0:b802fc31f1db | 639 | else |
| donatien | 0:b802fc31f1db | 640 | { |
| donatien | 0:b802fc31f1db | 641 | /* raw_len < len, not enough dst space */ |
| donatien | 0:b802fc31f1db | 642 | return ERR_ARG; |
| donatien | 0:b802fc31f1db | 643 | } |
| donatien | 0:b802fc31f1db | 644 | } |
| donatien | 0:b802fc31f1db | 645 | p = p->next; |
| donatien | 0:b802fc31f1db | 646 | } |
| donatien | 0:b802fc31f1db | 647 | /* p == NULL, ofs >= plen */ |
| donatien | 0:b802fc31f1db | 648 | return ERR_ARG; |
| donatien | 0:b802fc31f1db | 649 | } |
| donatien | 0:b802fc31f1db | 650 | else |
| donatien | 0:b802fc31f1db | 651 | { |
| donatien | 0:b802fc31f1db | 652 | /* len == 0, empty string */ |
| donatien | 0:b802fc31f1db | 653 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 654 | } |
| donatien | 0:b802fc31f1db | 655 | } |
| donatien | 0:b802fc31f1db | 656 | |
| donatien | 0:b802fc31f1db | 657 | #endif /* LWIP_SNMP */ |