Pehr Hovey
Some quick code to use UDP-only (no TCP) with mBed. Echos received packets and sends packets when a button is pressed
Core/lwIP/core/snmp/asn1_dec.c@0:a548a085de55, 2010-03-14 (annotated)
- Committer:
- pehrhovey
- Date:
- Sun Mar 14 00:54:12 2010 +0000
- Revision:
- 0:a548a085de55
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| pehrhovey | 0:a548a085de55 | 1 | /** |
| pehrhovey | 0:a548a085de55 | 2 | * @file |
| pehrhovey | 0:a548a085de55 | 3 | * Abstract Syntax Notation One (ISO 8824, 8825) decoding |
| pehrhovey | 0:a548a085de55 | 4 | * |
| pehrhovey | 0:a548a085de55 | 5 | * @todo not optimised (yet), favor correctness over speed, favor speed over size |
| pehrhovey | 0:a548a085de55 | 6 | */ |
| pehrhovey | 0:a548a085de55 | 7 | |
| pehrhovey | 0:a548a085de55 | 8 | /* |
| pehrhovey | 0:a548a085de55 | 9 | * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands. |
| pehrhovey | 0:a548a085de55 | 10 | * All rights reserved. |
| pehrhovey | 0:a548a085de55 | 11 | * |
| pehrhovey | 0:a548a085de55 | 12 | * Redistribution and use in source and binary forms, with or without modification, |
| pehrhovey | 0:a548a085de55 | 13 | * are permitted provided that the following conditions are met: |
| pehrhovey | 0:a548a085de55 | 14 | * |
| pehrhovey | 0:a548a085de55 | 15 | * 1. Redistributions of source code must retain the above copyright notice, |
| pehrhovey | 0:a548a085de55 | 16 | * this list of conditions and the following disclaimer. |
| pehrhovey | 0:a548a085de55 | 17 | * 2. Redistributions in binary form must reproduce the above copyright notice, |
| pehrhovey | 0:a548a085de55 | 18 | * this list of conditions and the following disclaimer in the documentation |
| pehrhovey | 0:a548a085de55 | 19 | * and/or other materials provided with the distribution. |
| pehrhovey | 0:a548a085de55 | 20 | * 3. The name of the author may not be used to endorse or promote products |
| pehrhovey | 0:a548a085de55 | 21 | * derived from this software without specific prior written permission. |
| pehrhovey | 0:a548a085de55 | 22 | * |
| pehrhovey | 0:a548a085de55 | 23 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| pehrhovey | 0:a548a085de55 | 24 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| pehrhovey | 0:a548a085de55 | 25 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT |
| pehrhovey | 0:a548a085de55 | 26 | * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| pehrhovey | 0:a548a085de55 | 27 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT |
| pehrhovey | 0:a548a085de55 | 28 | * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| pehrhovey | 0:a548a085de55 | 29 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| pehrhovey | 0:a548a085de55 | 30 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING |
| pehrhovey | 0:a548a085de55 | 31 | * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY |
| pehrhovey | 0:a548a085de55 | 32 | * OF SUCH DAMAGE. |
| pehrhovey | 0:a548a085de55 | 33 | * |
| pehrhovey | 0:a548a085de55 | 34 | * Author: Christiaan Simons <christiaan.simons@axon.tv> |
| pehrhovey | 0:a548a085de55 | 35 | */ |
| pehrhovey | 0:a548a085de55 | 36 | |
| pehrhovey | 0:a548a085de55 | 37 | #include "lwip/opt.h" |
| pehrhovey | 0:a548a085de55 | 38 | |
| pehrhovey | 0:a548a085de55 | 39 | #if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */ |
| pehrhovey | 0:a548a085de55 | 40 | |
| pehrhovey | 0:a548a085de55 | 41 | #include "lwip/snmp_asn1.h" |
| pehrhovey | 0:a548a085de55 | 42 | |
| pehrhovey | 0:a548a085de55 | 43 | /** |
| pehrhovey | 0:a548a085de55 | 44 | * Retrieves type field from incoming pbuf chain. |
| pehrhovey | 0:a548a085de55 | 45 | * |
| pehrhovey | 0:a548a085de55 | 46 | * @param p points to a pbuf holding an ASN1 coded type field |
| pehrhovey | 0:a548a085de55 | 47 | * @param ofs points to the offset within the pbuf chain of the ASN1 coded type field |
| pehrhovey | 0:a548a085de55 | 48 | * @param type return ASN1 type |
| pehrhovey | 0:a548a085de55 | 49 | * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode |
| pehrhovey | 0:a548a085de55 | 50 | */ |
| pehrhovey | 0:a548a085de55 | 51 | err_t |
| pehrhovey | 0:a548a085de55 | 52 | snmp_asn1_dec_type(struct pbuf *p, u16_t ofs, u8_t *type) |
| pehrhovey | 0:a548a085de55 | 53 | { |
| pehrhovey | 0:a548a085de55 | 54 | u16_t plen, base; |
| pehrhovey | 0:a548a085de55 | 55 | u8_t *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 56 | |
| pehrhovey | 0:a548a085de55 | 57 | plen = 0; |
| pehrhovey | 0:a548a085de55 | 58 | while (p != NULL) |
| pehrhovey | 0:a548a085de55 | 59 | { |
| pehrhovey | 0:a548a085de55 | 60 | base = plen; |
| pehrhovey | 0:a548a085de55 | 61 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 62 | if (ofs < plen) |
| pehrhovey | 0:a548a085de55 | 63 | { |
| pehrhovey | 0:a548a085de55 | 64 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 65 | msg_ptr += ofs - base; |
| pehrhovey | 0:a548a085de55 | 66 | *type = *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 67 | return ERR_OK; |
| pehrhovey | 0:a548a085de55 | 68 | } |
| pehrhovey | 0:a548a085de55 | 69 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 70 | } |
| pehrhovey | 0:a548a085de55 | 71 | /* p == NULL, ofs >= plen */ |
| pehrhovey | 0:a548a085de55 | 72 | return ERR_ARG; |
| pehrhovey | 0:a548a085de55 | 73 | } |
| pehrhovey | 0:a548a085de55 | 74 | |
| pehrhovey | 0:a548a085de55 | 75 | /** |
| pehrhovey | 0:a548a085de55 | 76 | * Decodes length field from incoming pbuf chain into host length. |
| pehrhovey | 0:a548a085de55 | 77 | * |
| pehrhovey | 0:a548a085de55 | 78 | * @param p points to a pbuf holding an ASN1 coded length |
| pehrhovey | 0:a548a085de55 | 79 | * @param ofs points to the offset within the pbuf chain of the ASN1 coded length |
| pehrhovey | 0:a548a085de55 | 80 | * @param octets_used returns number of octets used by the length code |
| pehrhovey | 0:a548a085de55 | 81 | * @param length return host order length, upto 64k |
| pehrhovey | 0:a548a085de55 | 82 | * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode |
| pehrhovey | 0:a548a085de55 | 83 | */ |
| pehrhovey | 0:a548a085de55 | 84 | err_t |
| pehrhovey | 0:a548a085de55 | 85 | snmp_asn1_dec_length(struct pbuf *p, u16_t ofs, u8_t *octets_used, u16_t *length) |
| pehrhovey | 0:a548a085de55 | 86 | { |
| pehrhovey | 0:a548a085de55 | 87 | u16_t plen, base; |
| pehrhovey | 0:a548a085de55 | 88 | u8_t *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 89 | |
| pehrhovey | 0:a548a085de55 | 90 | plen = 0; |
| pehrhovey | 0:a548a085de55 | 91 | while (p != NULL) |
| pehrhovey | 0:a548a085de55 | 92 | { |
| pehrhovey | 0:a548a085de55 | 93 | base = plen; |
| pehrhovey | 0:a548a085de55 | 94 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 95 | if (ofs < plen) |
| pehrhovey | 0:a548a085de55 | 96 | { |
| pehrhovey | 0:a548a085de55 | 97 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 98 | msg_ptr += ofs - base; |
| pehrhovey | 0:a548a085de55 | 99 | |
| pehrhovey | 0:a548a085de55 | 100 | if (*msg_ptr < 0x80) |
| pehrhovey | 0:a548a085de55 | 101 | { |
| pehrhovey | 0:a548a085de55 | 102 | /* primitive definite length format */ |
| pehrhovey | 0:a548a085de55 | 103 | *octets_used = 1; |
| pehrhovey | 0:a548a085de55 | 104 | *length = *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 105 | return ERR_OK; |
| pehrhovey | 0:a548a085de55 | 106 | } |
| pehrhovey | 0:a548a085de55 | 107 | else if (*msg_ptr == 0x80) |
| pehrhovey | 0:a548a085de55 | 108 | { |
| pehrhovey | 0:a548a085de55 | 109 | /* constructed indefinite length format, termination with two zero octets */ |
| pehrhovey | 0:a548a085de55 | 110 | u8_t zeros; |
| pehrhovey | 0:a548a085de55 | 111 | u8_t i; |
| pehrhovey | 0:a548a085de55 | 112 | |
| pehrhovey | 0:a548a085de55 | 113 | *length = 0; |
| pehrhovey | 0:a548a085de55 | 114 | zeros = 0; |
| pehrhovey | 0:a548a085de55 | 115 | while (zeros != 2) |
| pehrhovey | 0:a548a085de55 | 116 | { |
| pehrhovey | 0:a548a085de55 | 117 | i = 2; |
| pehrhovey | 0:a548a085de55 | 118 | while (i > 0) |
| pehrhovey | 0:a548a085de55 | 119 | { |
| pehrhovey | 0:a548a085de55 | 120 | i--; |
| pehrhovey | 0:a548a085de55 | 121 | (*length) += 1; |
| pehrhovey | 0:a548a085de55 | 122 | ofs += 1; |
| pehrhovey | 0:a548a085de55 | 123 | if (ofs >= plen) |
| pehrhovey | 0:a548a085de55 | 124 | { |
| pehrhovey | 0:a548a085de55 | 125 | /* next octet in next pbuf */ |
| pehrhovey | 0:a548a085de55 | 126 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 127 | if (p == NULL) { return ERR_ARG; } |
| pehrhovey | 0:a548a085de55 | 128 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 129 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 130 | } |
| pehrhovey | 0:a548a085de55 | 131 | else |
| pehrhovey | 0:a548a085de55 | 132 | { |
| pehrhovey | 0:a548a085de55 | 133 | /* next octet in same pbuf */ |
| pehrhovey | 0:a548a085de55 | 134 | msg_ptr++; |
| pehrhovey | 0:a548a085de55 | 135 | } |
| pehrhovey | 0:a548a085de55 | 136 | if (*msg_ptr == 0) |
| pehrhovey | 0:a548a085de55 | 137 | { |
| pehrhovey | 0:a548a085de55 | 138 | zeros++; |
| pehrhovey | 0:a548a085de55 | 139 | if (zeros == 2) |
| pehrhovey | 0:a548a085de55 | 140 | { |
| pehrhovey | 0:a548a085de55 | 141 | /* stop while (i > 0) */ |
| pehrhovey | 0:a548a085de55 | 142 | i = 0; |
| pehrhovey | 0:a548a085de55 | 143 | } |
| pehrhovey | 0:a548a085de55 | 144 | } |
| pehrhovey | 0:a548a085de55 | 145 | else |
| pehrhovey | 0:a548a085de55 | 146 | { |
| pehrhovey | 0:a548a085de55 | 147 | zeros = 0; |
| pehrhovey | 0:a548a085de55 | 148 | } |
| pehrhovey | 0:a548a085de55 | 149 | } |
| pehrhovey | 0:a548a085de55 | 150 | } |
| pehrhovey | 0:a548a085de55 | 151 | *octets_used = 1; |
| pehrhovey | 0:a548a085de55 | 152 | return ERR_OK; |
| pehrhovey | 0:a548a085de55 | 153 | } |
| pehrhovey | 0:a548a085de55 | 154 | else if (*msg_ptr == 0x81) |
| pehrhovey | 0:a548a085de55 | 155 | { |
| pehrhovey | 0:a548a085de55 | 156 | /* constructed definite length format, one octet */ |
| pehrhovey | 0:a548a085de55 | 157 | ofs += 1; |
| pehrhovey | 0:a548a085de55 | 158 | if (ofs >= plen) |
| pehrhovey | 0:a548a085de55 | 159 | { |
| pehrhovey | 0:a548a085de55 | 160 | /* next octet in next pbuf */ |
| pehrhovey | 0:a548a085de55 | 161 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 162 | if (p == NULL) { return ERR_ARG; } |
| pehrhovey | 0:a548a085de55 | 163 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 164 | } |
| pehrhovey | 0:a548a085de55 | 165 | else |
| pehrhovey | 0:a548a085de55 | 166 | { |
| pehrhovey | 0:a548a085de55 | 167 | /* next octet in same pbuf */ |
| pehrhovey | 0:a548a085de55 | 168 | msg_ptr++; |
| pehrhovey | 0:a548a085de55 | 169 | } |
| pehrhovey | 0:a548a085de55 | 170 | *length = *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 171 | *octets_used = 2; |
| pehrhovey | 0:a548a085de55 | 172 | return ERR_OK; |
| pehrhovey | 0:a548a085de55 | 173 | } |
| pehrhovey | 0:a548a085de55 | 174 | else if (*msg_ptr == 0x82) |
| pehrhovey | 0:a548a085de55 | 175 | { |
| pehrhovey | 0:a548a085de55 | 176 | u8_t i; |
| pehrhovey | 0:a548a085de55 | 177 | |
| pehrhovey | 0:a548a085de55 | 178 | /* constructed definite length format, two octets */ |
| pehrhovey | 0:a548a085de55 | 179 | i = 2; |
| pehrhovey | 0:a548a085de55 | 180 | while (i > 0) |
| pehrhovey | 0:a548a085de55 | 181 | { |
| pehrhovey | 0:a548a085de55 | 182 | i--; |
| pehrhovey | 0:a548a085de55 | 183 | ofs += 1; |
| pehrhovey | 0:a548a085de55 | 184 | if (ofs >= plen) |
| pehrhovey | 0:a548a085de55 | 185 | { |
| pehrhovey | 0:a548a085de55 | 186 | /* next octet in next pbuf */ |
| pehrhovey | 0:a548a085de55 | 187 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 188 | if (p == NULL) { return ERR_ARG; } |
| pehrhovey | 0:a548a085de55 | 189 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 190 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 191 | } |
| pehrhovey | 0:a548a085de55 | 192 | else |
| pehrhovey | 0:a548a085de55 | 193 | { |
| pehrhovey | 0:a548a085de55 | 194 | /* next octet in same pbuf */ |
| pehrhovey | 0:a548a085de55 | 195 | msg_ptr++; |
| pehrhovey | 0:a548a085de55 | 196 | } |
| pehrhovey | 0:a548a085de55 | 197 | if (i == 0) |
| pehrhovey | 0:a548a085de55 | 198 | { |
| pehrhovey | 0:a548a085de55 | 199 | /* least significant length octet */ |
| pehrhovey | 0:a548a085de55 | 200 | *length |= *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 201 | } |
| pehrhovey | 0:a548a085de55 | 202 | else |
| pehrhovey | 0:a548a085de55 | 203 | { |
| pehrhovey | 0:a548a085de55 | 204 | /* most significant length octet */ |
| pehrhovey | 0:a548a085de55 | 205 | *length = (*msg_ptr) << 8; |
| pehrhovey | 0:a548a085de55 | 206 | } |
| pehrhovey | 0:a548a085de55 | 207 | } |
| pehrhovey | 0:a548a085de55 | 208 | *octets_used = 3; |
| pehrhovey | 0:a548a085de55 | 209 | return ERR_OK; |
| pehrhovey | 0:a548a085de55 | 210 | } |
| pehrhovey | 0:a548a085de55 | 211 | else |
| pehrhovey | 0:a548a085de55 | 212 | { |
| pehrhovey | 0:a548a085de55 | 213 | /* constructed definite length format 3..127 octets, this is too big (>64k) */ |
| pehrhovey | 0:a548a085de55 | 214 | /** @todo: do we need to accept inefficient codings with many leading zero's? */ |
| pehrhovey | 0:a548a085de55 | 215 | *octets_used = 1 + ((*msg_ptr) & 0x7f); |
| pehrhovey | 0:a548a085de55 | 216 | return ERR_ARG; |
| pehrhovey | 0:a548a085de55 | 217 | } |
| pehrhovey | 0:a548a085de55 | 218 | } |
| pehrhovey | 0:a548a085de55 | 219 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 220 | } |
| pehrhovey | 0:a548a085de55 | 221 | |
| pehrhovey | 0:a548a085de55 | 222 | /* p == NULL, ofs >= plen */ |
| pehrhovey | 0:a548a085de55 | 223 | return ERR_ARG; |
| pehrhovey | 0:a548a085de55 | 224 | } |
| pehrhovey | 0:a548a085de55 | 225 | |
| pehrhovey | 0:a548a085de55 | 226 | /** |
| pehrhovey | 0:a548a085de55 | 227 | * Decodes positive integer (counter, gauge, timeticks) into u32_t. |
| pehrhovey | 0:a548a085de55 | 228 | * |
| pehrhovey | 0:a548a085de55 | 229 | * @param p points to a pbuf holding an ASN1 coded integer |
| pehrhovey | 0:a548a085de55 | 230 | * @param ofs points to the offset within the pbuf chain of the ASN1 coded integer |
| pehrhovey | 0:a548a085de55 | 231 | * @param len length of the coded integer field |
| pehrhovey | 0:a548a085de55 | 232 | * @param value return host order integer |
| pehrhovey | 0:a548a085de55 | 233 | * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode |
| pehrhovey | 0:a548a085de55 | 234 | * |
| pehrhovey | 0:a548a085de55 | 235 | * @note ASN coded integers are _always_ signed. E.g. +0xFFFF is coded |
| pehrhovey | 0:a548a085de55 | 236 | * as 0x00,0xFF,0xFF. Note the leading sign octet. A positive value |
| pehrhovey | 0:a548a085de55 | 237 | * of 0xFFFFFFFF is preceded with 0x00 and the length is 5 octets!! |
| pehrhovey | 0:a548a085de55 | 238 | */ |
| pehrhovey | 0:a548a085de55 | 239 | err_t |
| pehrhovey | 0:a548a085de55 | 240 | snmp_asn1_dec_u32t(struct pbuf *p, u16_t ofs, u16_t len, u32_t *value) |
| pehrhovey | 0:a548a085de55 | 241 | { |
| pehrhovey | 0:a548a085de55 | 242 | u16_t plen, base; |
| pehrhovey | 0:a548a085de55 | 243 | u8_t *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 244 | |
| pehrhovey | 0:a548a085de55 | 245 | plen = 0; |
| pehrhovey | 0:a548a085de55 | 246 | while (p != NULL) |
| pehrhovey | 0:a548a085de55 | 247 | { |
| pehrhovey | 0:a548a085de55 | 248 | base = plen; |
| pehrhovey | 0:a548a085de55 | 249 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 250 | if (ofs < plen) |
| pehrhovey | 0:a548a085de55 | 251 | { |
| pehrhovey | 0:a548a085de55 | 252 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 253 | msg_ptr += ofs - base; |
| pehrhovey | 0:a548a085de55 | 254 | if ((len > 0) && (len < 6)) |
| pehrhovey | 0:a548a085de55 | 255 | { |
| pehrhovey | 0:a548a085de55 | 256 | /* start from zero */ |
| pehrhovey | 0:a548a085de55 | 257 | *value = 0; |
| pehrhovey | 0:a548a085de55 | 258 | if (*msg_ptr & 0x80) |
| pehrhovey | 0:a548a085de55 | 259 | { |
| pehrhovey | 0:a548a085de55 | 260 | /* negative, expecting zero sign bit! */ |
| pehrhovey | 0:a548a085de55 | 261 | return ERR_ARG; |
| pehrhovey | 0:a548a085de55 | 262 | } |
| pehrhovey | 0:a548a085de55 | 263 | else |
| pehrhovey | 0:a548a085de55 | 264 | { |
| pehrhovey | 0:a548a085de55 | 265 | /* positive */ |
| pehrhovey | 0:a548a085de55 | 266 | if ((len > 1) && (*msg_ptr == 0)) |
| pehrhovey | 0:a548a085de55 | 267 | { |
| pehrhovey | 0:a548a085de55 | 268 | /* skip leading "sign byte" octet 0x00 */ |
| pehrhovey | 0:a548a085de55 | 269 | len--; |
| pehrhovey | 0:a548a085de55 | 270 | ofs += 1; |
| pehrhovey | 0:a548a085de55 | 271 | if (ofs >= plen) |
| pehrhovey | 0:a548a085de55 | 272 | { |
| pehrhovey | 0:a548a085de55 | 273 | /* next octet in next pbuf */ |
| pehrhovey | 0:a548a085de55 | 274 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 275 | if (p == NULL) { return ERR_ARG; } |
| pehrhovey | 0:a548a085de55 | 276 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 277 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 278 | } |
| pehrhovey | 0:a548a085de55 | 279 | else |
| pehrhovey | 0:a548a085de55 | 280 | { |
| pehrhovey | 0:a548a085de55 | 281 | /* next octet in same pbuf */ |
| pehrhovey | 0:a548a085de55 | 282 | msg_ptr++; |
| pehrhovey | 0:a548a085de55 | 283 | } |
| pehrhovey | 0:a548a085de55 | 284 | } |
| pehrhovey | 0:a548a085de55 | 285 | } |
| pehrhovey | 0:a548a085de55 | 286 | /* OR octets with value */ |
| pehrhovey | 0:a548a085de55 | 287 | while (len > 1) |
| pehrhovey | 0:a548a085de55 | 288 | { |
| pehrhovey | 0:a548a085de55 | 289 | len--; |
| pehrhovey | 0:a548a085de55 | 290 | *value |= *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 291 | *value <<= 8; |
| pehrhovey | 0:a548a085de55 | 292 | ofs += 1; |
| pehrhovey | 0:a548a085de55 | 293 | if (ofs >= plen) |
| pehrhovey | 0:a548a085de55 | 294 | { |
| pehrhovey | 0:a548a085de55 | 295 | /* next octet in next pbuf */ |
| pehrhovey | 0:a548a085de55 | 296 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 297 | if (p == NULL) { return ERR_ARG; } |
| pehrhovey | 0:a548a085de55 | 298 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 299 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 300 | } |
| pehrhovey | 0:a548a085de55 | 301 | else |
| pehrhovey | 0:a548a085de55 | 302 | { |
| pehrhovey | 0:a548a085de55 | 303 | /* next octet in same pbuf */ |
| pehrhovey | 0:a548a085de55 | 304 | msg_ptr++; |
| pehrhovey | 0:a548a085de55 | 305 | } |
| pehrhovey | 0:a548a085de55 | 306 | } |
| pehrhovey | 0:a548a085de55 | 307 | *value |= *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 308 | return ERR_OK; |
| pehrhovey | 0:a548a085de55 | 309 | } |
| pehrhovey | 0:a548a085de55 | 310 | else |
| pehrhovey | 0:a548a085de55 | 311 | { |
| pehrhovey | 0:a548a085de55 | 312 | return ERR_ARG; |
| pehrhovey | 0:a548a085de55 | 313 | } |
| pehrhovey | 0:a548a085de55 | 314 | } |
| pehrhovey | 0:a548a085de55 | 315 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 316 | } |
| pehrhovey | 0:a548a085de55 | 317 | /* p == NULL, ofs >= plen */ |
| pehrhovey | 0:a548a085de55 | 318 | return ERR_ARG; |
| pehrhovey | 0:a548a085de55 | 319 | } |
| pehrhovey | 0:a548a085de55 | 320 | |
| pehrhovey | 0:a548a085de55 | 321 | /** |
| pehrhovey | 0:a548a085de55 | 322 | * Decodes integer into s32_t. |
| pehrhovey | 0:a548a085de55 | 323 | * |
| pehrhovey | 0:a548a085de55 | 324 | * @param p points to a pbuf holding an ASN1 coded integer |
| pehrhovey | 0:a548a085de55 | 325 | * @param ofs points to the offset within the pbuf chain of the ASN1 coded integer |
| pehrhovey | 0:a548a085de55 | 326 | * @param len length of the coded integer field |
| pehrhovey | 0:a548a085de55 | 327 | * @param value return host order integer |
| pehrhovey | 0:a548a085de55 | 328 | * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode |
| pehrhovey | 0:a548a085de55 | 329 | * |
| pehrhovey | 0:a548a085de55 | 330 | * @note ASN coded integers are _always_ signed! |
| pehrhovey | 0:a548a085de55 | 331 | */ |
| pehrhovey | 0:a548a085de55 | 332 | err_t |
| pehrhovey | 0:a548a085de55 | 333 | snmp_asn1_dec_s32t(struct pbuf *p, u16_t ofs, u16_t len, s32_t *value) |
| pehrhovey | 0:a548a085de55 | 334 | { |
| pehrhovey | 0:a548a085de55 | 335 | u16_t plen, base; |
| pehrhovey | 0:a548a085de55 | 336 | u8_t *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 337 | #if BYTE_ORDER == LITTLE_ENDIAN |
| pehrhovey | 0:a548a085de55 | 338 | u8_t *lsb_ptr = (u8_t*)value; |
| pehrhovey | 0:a548a085de55 | 339 | #endif |
| pehrhovey | 0:a548a085de55 | 340 | #if BYTE_ORDER == BIG_ENDIAN |
| pehrhovey | 0:a548a085de55 | 341 | u8_t *lsb_ptr = (u8_t*)value + sizeof(s32_t) - 1; |
| pehrhovey | 0:a548a085de55 | 342 | #endif |
| pehrhovey | 0:a548a085de55 | 343 | u8_t sign; |
| pehrhovey | 0:a548a085de55 | 344 | |
| pehrhovey | 0:a548a085de55 | 345 | plen = 0; |
| pehrhovey | 0:a548a085de55 | 346 | while (p != NULL) |
| pehrhovey | 0:a548a085de55 | 347 | { |
| pehrhovey | 0:a548a085de55 | 348 | base = plen; |
| pehrhovey | 0:a548a085de55 | 349 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 350 | if (ofs < plen) |
| pehrhovey | 0:a548a085de55 | 351 | { |
| pehrhovey | 0:a548a085de55 | 352 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 353 | msg_ptr += ofs - base; |
| pehrhovey | 0:a548a085de55 | 354 | if ((len > 0) && (len < 5)) |
| pehrhovey | 0:a548a085de55 | 355 | { |
| pehrhovey | 0:a548a085de55 | 356 | if (*msg_ptr & 0x80) |
| pehrhovey | 0:a548a085de55 | 357 | { |
| pehrhovey | 0:a548a085de55 | 358 | /* negative, start from -1 */ |
| pehrhovey | 0:a548a085de55 | 359 | *value = -1; |
| pehrhovey | 0:a548a085de55 | 360 | sign = 1; |
| pehrhovey | 0:a548a085de55 | 361 | } |
| pehrhovey | 0:a548a085de55 | 362 | else |
| pehrhovey | 0:a548a085de55 | 363 | { |
| pehrhovey | 0:a548a085de55 | 364 | /* positive, start from 0 */ |
| pehrhovey | 0:a548a085de55 | 365 | *value = 0; |
| pehrhovey | 0:a548a085de55 | 366 | sign = 0; |
| pehrhovey | 0:a548a085de55 | 367 | } |
| pehrhovey | 0:a548a085de55 | 368 | /* OR/AND octets with value */ |
| pehrhovey | 0:a548a085de55 | 369 | while (len > 1) |
| pehrhovey | 0:a548a085de55 | 370 | { |
| pehrhovey | 0:a548a085de55 | 371 | len--; |
| pehrhovey | 0:a548a085de55 | 372 | if (sign) |
| pehrhovey | 0:a548a085de55 | 373 | { |
| pehrhovey | 0:a548a085de55 | 374 | *lsb_ptr &= *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 375 | *value <<= 8; |
| pehrhovey | 0:a548a085de55 | 376 | *lsb_ptr |= 255; |
| pehrhovey | 0:a548a085de55 | 377 | } |
| pehrhovey | 0:a548a085de55 | 378 | else |
| pehrhovey | 0:a548a085de55 | 379 | { |
| pehrhovey | 0:a548a085de55 | 380 | *lsb_ptr |= *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 381 | *value <<= 8; |
| pehrhovey | 0:a548a085de55 | 382 | } |
| pehrhovey | 0:a548a085de55 | 383 | ofs += 1; |
| pehrhovey | 0:a548a085de55 | 384 | if (ofs >= plen) |
| pehrhovey | 0:a548a085de55 | 385 | { |
| pehrhovey | 0:a548a085de55 | 386 | /* next octet in next pbuf */ |
| pehrhovey | 0:a548a085de55 | 387 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 388 | if (p == NULL) { return ERR_ARG; } |
| pehrhovey | 0:a548a085de55 | 389 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 390 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 391 | } |
| pehrhovey | 0:a548a085de55 | 392 | else |
| pehrhovey | 0:a548a085de55 | 393 | { |
| pehrhovey | 0:a548a085de55 | 394 | /* next octet in same pbuf */ |
| pehrhovey | 0:a548a085de55 | 395 | msg_ptr++; |
| pehrhovey | 0:a548a085de55 | 396 | } |
| pehrhovey | 0:a548a085de55 | 397 | } |
| pehrhovey | 0:a548a085de55 | 398 | if (sign) |
| pehrhovey | 0:a548a085de55 | 399 | { |
| pehrhovey | 0:a548a085de55 | 400 | *lsb_ptr &= *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 401 | } |
| pehrhovey | 0:a548a085de55 | 402 | else |
| pehrhovey | 0:a548a085de55 | 403 | { |
| pehrhovey | 0:a548a085de55 | 404 | *lsb_ptr |= *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 405 | } |
| pehrhovey | 0:a548a085de55 | 406 | return ERR_OK; |
| pehrhovey | 0:a548a085de55 | 407 | } |
| pehrhovey | 0:a548a085de55 | 408 | else |
| pehrhovey | 0:a548a085de55 | 409 | { |
| pehrhovey | 0:a548a085de55 | 410 | return ERR_ARG; |
| pehrhovey | 0:a548a085de55 | 411 | } |
| pehrhovey | 0:a548a085de55 | 412 | } |
| pehrhovey | 0:a548a085de55 | 413 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 414 | } |
| pehrhovey | 0:a548a085de55 | 415 | /* p == NULL, ofs >= plen */ |
| pehrhovey | 0:a548a085de55 | 416 | return ERR_ARG; |
| pehrhovey | 0:a548a085de55 | 417 | } |
| pehrhovey | 0:a548a085de55 | 418 | |
| pehrhovey | 0:a548a085de55 | 419 | /** |
| pehrhovey | 0:a548a085de55 | 420 | * Decodes object identifier from incoming message into array of s32_t. |
| pehrhovey | 0:a548a085de55 | 421 | * |
| pehrhovey | 0:a548a085de55 | 422 | * @param p points to a pbuf holding an ASN1 coded object identifier |
| pehrhovey | 0:a548a085de55 | 423 | * @param ofs points to the offset within the pbuf chain of the ASN1 coded object identifier |
| pehrhovey | 0:a548a085de55 | 424 | * @param len length of the coded object identifier |
| pehrhovey | 0:a548a085de55 | 425 | * @param oid return object identifier struct |
| pehrhovey | 0:a548a085de55 | 426 | * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode |
| pehrhovey | 0:a548a085de55 | 427 | */ |
| pehrhovey | 0:a548a085de55 | 428 | err_t |
| pehrhovey | 0:a548a085de55 | 429 | snmp_asn1_dec_oid(struct pbuf *p, u16_t ofs, u16_t len, struct snmp_obj_id *oid) |
| pehrhovey | 0:a548a085de55 | 430 | { |
| pehrhovey | 0:a548a085de55 | 431 | u16_t plen, base; |
| pehrhovey | 0:a548a085de55 | 432 | u8_t *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 433 | s32_t *oid_ptr; |
| pehrhovey | 0:a548a085de55 | 434 | |
| pehrhovey | 0:a548a085de55 | 435 | plen = 0; |
| pehrhovey | 0:a548a085de55 | 436 | while (p != NULL) |
| pehrhovey | 0:a548a085de55 | 437 | { |
| pehrhovey | 0:a548a085de55 | 438 | base = plen; |
| pehrhovey | 0:a548a085de55 | 439 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 440 | if (ofs < plen) |
| pehrhovey | 0:a548a085de55 | 441 | { |
| pehrhovey | 0:a548a085de55 | 442 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 443 | msg_ptr += ofs - base; |
| pehrhovey | 0:a548a085de55 | 444 | |
| pehrhovey | 0:a548a085de55 | 445 | oid->len = 0; |
| pehrhovey | 0:a548a085de55 | 446 | oid_ptr = &oid->id[0]; |
| pehrhovey | 0:a548a085de55 | 447 | if (len > 0) |
| pehrhovey | 0:a548a085de55 | 448 | { |
| pehrhovey | 0:a548a085de55 | 449 | /* first compressed octet */ |
| pehrhovey | 0:a548a085de55 | 450 | if (*msg_ptr == 0x2B) |
| pehrhovey | 0:a548a085de55 | 451 | { |
| pehrhovey | 0:a548a085de55 | 452 | /* (most) common case 1.3 (iso.org) */ |
| pehrhovey | 0:a548a085de55 | 453 | *oid_ptr = 1; |
| pehrhovey | 0:a548a085de55 | 454 | oid_ptr++; |
| pehrhovey | 0:a548a085de55 | 455 | *oid_ptr = 3; |
| pehrhovey | 0:a548a085de55 | 456 | oid_ptr++; |
| pehrhovey | 0:a548a085de55 | 457 | } |
| pehrhovey | 0:a548a085de55 | 458 | else if (*msg_ptr < 40) |
| pehrhovey | 0:a548a085de55 | 459 | { |
| pehrhovey | 0:a548a085de55 | 460 | *oid_ptr = 0; |
| pehrhovey | 0:a548a085de55 | 461 | oid_ptr++; |
| pehrhovey | 0:a548a085de55 | 462 | *oid_ptr = *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 463 | oid_ptr++; |
| pehrhovey | 0:a548a085de55 | 464 | } |
| pehrhovey | 0:a548a085de55 | 465 | else if (*msg_ptr < 80) |
| pehrhovey | 0:a548a085de55 | 466 | { |
| pehrhovey | 0:a548a085de55 | 467 | *oid_ptr = 1; |
| pehrhovey | 0:a548a085de55 | 468 | oid_ptr++; |
| pehrhovey | 0:a548a085de55 | 469 | *oid_ptr = (*msg_ptr) - 40; |
| pehrhovey | 0:a548a085de55 | 470 | oid_ptr++; |
| pehrhovey | 0:a548a085de55 | 471 | } |
| pehrhovey | 0:a548a085de55 | 472 | else |
| pehrhovey | 0:a548a085de55 | 473 | { |
| pehrhovey | 0:a548a085de55 | 474 | *oid_ptr = 2; |
| pehrhovey | 0:a548a085de55 | 475 | oid_ptr++; |
| pehrhovey | 0:a548a085de55 | 476 | *oid_ptr = (*msg_ptr) - 80; |
| pehrhovey | 0:a548a085de55 | 477 | oid_ptr++; |
| pehrhovey | 0:a548a085de55 | 478 | } |
| pehrhovey | 0:a548a085de55 | 479 | oid->len = 2; |
| pehrhovey | 0:a548a085de55 | 480 | } |
| pehrhovey | 0:a548a085de55 | 481 | else |
| pehrhovey | 0:a548a085de55 | 482 | { |
| pehrhovey | 0:a548a085de55 | 483 | /* accepting zero length identifiers e.g. for |
| pehrhovey | 0:a548a085de55 | 484 | getnext operation. uncommon but valid */ |
| pehrhovey | 0:a548a085de55 | 485 | return ERR_OK; |
| pehrhovey | 0:a548a085de55 | 486 | } |
| pehrhovey | 0:a548a085de55 | 487 | len--; |
| pehrhovey | 0:a548a085de55 | 488 | if (len > 0) |
| pehrhovey | 0:a548a085de55 | 489 | { |
| pehrhovey | 0:a548a085de55 | 490 | ofs += 1; |
| pehrhovey | 0:a548a085de55 | 491 | if (ofs >= plen) |
| pehrhovey | 0:a548a085de55 | 492 | { |
| pehrhovey | 0:a548a085de55 | 493 | /* next octet in next pbuf */ |
| pehrhovey | 0:a548a085de55 | 494 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 495 | if (p == NULL) { return ERR_ARG; } |
| pehrhovey | 0:a548a085de55 | 496 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 497 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 498 | } |
| pehrhovey | 0:a548a085de55 | 499 | else |
| pehrhovey | 0:a548a085de55 | 500 | { |
| pehrhovey | 0:a548a085de55 | 501 | /* next octet in same pbuf */ |
| pehrhovey | 0:a548a085de55 | 502 | msg_ptr++; |
| pehrhovey | 0:a548a085de55 | 503 | } |
| pehrhovey | 0:a548a085de55 | 504 | } |
| pehrhovey | 0:a548a085de55 | 505 | while ((len > 0) && (oid->len < LWIP_SNMP_OBJ_ID_LEN)) |
| pehrhovey | 0:a548a085de55 | 506 | { |
| pehrhovey | 0:a548a085de55 | 507 | /* sub-identifier uses multiple octets */ |
| pehrhovey | 0:a548a085de55 | 508 | if (*msg_ptr & 0x80) |
| pehrhovey | 0:a548a085de55 | 509 | { |
| pehrhovey | 0:a548a085de55 | 510 | s32_t sub_id = 0; |
| pehrhovey | 0:a548a085de55 | 511 | |
| pehrhovey | 0:a548a085de55 | 512 | while ((*msg_ptr & 0x80) && (len > 1)) |
| pehrhovey | 0:a548a085de55 | 513 | { |
| pehrhovey | 0:a548a085de55 | 514 | len--; |
| pehrhovey | 0:a548a085de55 | 515 | sub_id = (sub_id << 7) + (*msg_ptr & ~0x80); |
| pehrhovey | 0:a548a085de55 | 516 | ofs += 1; |
| pehrhovey | 0:a548a085de55 | 517 | if (ofs >= plen) |
| pehrhovey | 0:a548a085de55 | 518 | { |
| pehrhovey | 0:a548a085de55 | 519 | /* next octet in next pbuf */ |
| pehrhovey | 0:a548a085de55 | 520 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 521 | if (p == NULL) { return ERR_ARG; } |
| pehrhovey | 0:a548a085de55 | 522 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 523 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 524 | } |
| pehrhovey | 0:a548a085de55 | 525 | else |
| pehrhovey | 0:a548a085de55 | 526 | { |
| pehrhovey | 0:a548a085de55 | 527 | /* next octet in same pbuf */ |
| pehrhovey | 0:a548a085de55 | 528 | msg_ptr++; |
| pehrhovey | 0:a548a085de55 | 529 | } |
| pehrhovey | 0:a548a085de55 | 530 | } |
| pehrhovey | 0:a548a085de55 | 531 | if (!(*msg_ptr & 0x80) && (len > 0)) |
| pehrhovey | 0:a548a085de55 | 532 | { |
| pehrhovey | 0:a548a085de55 | 533 | /* last octet sub-identifier */ |
| pehrhovey | 0:a548a085de55 | 534 | len--; |
| pehrhovey | 0:a548a085de55 | 535 | sub_id = (sub_id << 7) + *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 536 | *oid_ptr = sub_id; |
| pehrhovey | 0:a548a085de55 | 537 | } |
| pehrhovey | 0:a548a085de55 | 538 | } |
| pehrhovey | 0:a548a085de55 | 539 | else |
| pehrhovey | 0:a548a085de55 | 540 | { |
| pehrhovey | 0:a548a085de55 | 541 | /* !(*msg_ptr & 0x80) sub-identifier uses single octet */ |
| pehrhovey | 0:a548a085de55 | 542 | len--; |
| pehrhovey | 0:a548a085de55 | 543 | *oid_ptr = *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 544 | } |
| pehrhovey | 0:a548a085de55 | 545 | if (len > 0) |
| pehrhovey | 0:a548a085de55 | 546 | { |
| pehrhovey | 0:a548a085de55 | 547 | /* remaining oid bytes available ... */ |
| pehrhovey | 0:a548a085de55 | 548 | ofs += 1; |
| pehrhovey | 0:a548a085de55 | 549 | if (ofs >= plen) |
| pehrhovey | 0:a548a085de55 | 550 | { |
| pehrhovey | 0:a548a085de55 | 551 | /* next octet in next pbuf */ |
| pehrhovey | 0:a548a085de55 | 552 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 553 | if (p == NULL) { return ERR_ARG; } |
| pehrhovey | 0:a548a085de55 | 554 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 555 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 556 | } |
| pehrhovey | 0:a548a085de55 | 557 | else |
| pehrhovey | 0:a548a085de55 | 558 | { |
| pehrhovey | 0:a548a085de55 | 559 | /* next octet in same pbuf */ |
| pehrhovey | 0:a548a085de55 | 560 | msg_ptr++; |
| pehrhovey | 0:a548a085de55 | 561 | } |
| pehrhovey | 0:a548a085de55 | 562 | } |
| pehrhovey | 0:a548a085de55 | 563 | oid_ptr++; |
| pehrhovey | 0:a548a085de55 | 564 | oid->len++; |
| pehrhovey | 0:a548a085de55 | 565 | } |
| pehrhovey | 0:a548a085de55 | 566 | if (len == 0) |
| pehrhovey | 0:a548a085de55 | 567 | { |
| pehrhovey | 0:a548a085de55 | 568 | /* len == 0, end of oid */ |
| pehrhovey | 0:a548a085de55 | 569 | return ERR_OK; |
| pehrhovey | 0:a548a085de55 | 570 | } |
| pehrhovey | 0:a548a085de55 | 571 | else |
| pehrhovey | 0:a548a085de55 | 572 | { |
| pehrhovey | 0:a548a085de55 | 573 | /* len > 0, oid->len == LWIP_SNMP_OBJ_ID_LEN or malformed encoding */ |
| pehrhovey | 0:a548a085de55 | 574 | return ERR_ARG; |
| pehrhovey | 0:a548a085de55 | 575 | } |
| pehrhovey | 0:a548a085de55 | 576 | |
| pehrhovey | 0:a548a085de55 | 577 | } |
| pehrhovey | 0:a548a085de55 | 578 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 579 | } |
| pehrhovey | 0:a548a085de55 | 580 | /* p == NULL, ofs >= plen */ |
| pehrhovey | 0:a548a085de55 | 581 | return ERR_ARG; |
| pehrhovey | 0:a548a085de55 | 582 | } |
| pehrhovey | 0:a548a085de55 | 583 | |
| pehrhovey | 0:a548a085de55 | 584 | /** |
| pehrhovey | 0:a548a085de55 | 585 | * Decodes (copies) raw data (ip-addresses, octet strings, opaque encoding) |
| pehrhovey | 0:a548a085de55 | 586 | * from incoming message into array. |
| pehrhovey | 0:a548a085de55 | 587 | * |
| pehrhovey | 0:a548a085de55 | 588 | * @param p points to a pbuf holding an ASN1 coded raw data |
| pehrhovey | 0:a548a085de55 | 589 | * @param ofs points to the offset within the pbuf chain of the ASN1 coded raw data |
| pehrhovey | 0:a548a085de55 | 590 | * @param len length of the coded raw data (zero is valid, e.g. empty string!) |
| pehrhovey | 0:a548a085de55 | 591 | * @param raw_len length of the raw return value |
| pehrhovey | 0:a548a085de55 | 592 | * @param raw return raw bytes |
| pehrhovey | 0:a548a085de55 | 593 | * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) decode |
| pehrhovey | 0:a548a085de55 | 594 | */ |
| pehrhovey | 0:a548a085de55 | 595 | err_t |
| pehrhovey | 0:a548a085de55 | 596 | snmp_asn1_dec_raw(struct pbuf *p, u16_t ofs, u16_t len, u16_t raw_len, u8_t *raw) |
| pehrhovey | 0:a548a085de55 | 597 | { |
| pehrhovey | 0:a548a085de55 | 598 | u16_t plen, base; |
| pehrhovey | 0:a548a085de55 | 599 | u8_t *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 600 | |
| pehrhovey | 0:a548a085de55 | 601 | if (len > 0) |
| pehrhovey | 0:a548a085de55 | 602 | { |
| pehrhovey | 0:a548a085de55 | 603 | plen = 0; |
| pehrhovey | 0:a548a085de55 | 604 | while (p != NULL) |
| pehrhovey | 0:a548a085de55 | 605 | { |
| pehrhovey | 0:a548a085de55 | 606 | base = plen; |
| pehrhovey | 0:a548a085de55 | 607 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 608 | if (ofs < plen) |
| pehrhovey | 0:a548a085de55 | 609 | { |
| pehrhovey | 0:a548a085de55 | 610 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 611 | msg_ptr += ofs - base; |
| pehrhovey | 0:a548a085de55 | 612 | if (raw_len >= len) |
| pehrhovey | 0:a548a085de55 | 613 | { |
| pehrhovey | 0:a548a085de55 | 614 | while (len > 1) |
| pehrhovey | 0:a548a085de55 | 615 | { |
| pehrhovey | 0:a548a085de55 | 616 | /* copy len - 1 octets */ |
| pehrhovey | 0:a548a085de55 | 617 | len--; |
| pehrhovey | 0:a548a085de55 | 618 | *raw = *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 619 | raw++; |
| pehrhovey | 0:a548a085de55 | 620 | ofs += 1; |
| pehrhovey | 0:a548a085de55 | 621 | if (ofs >= plen) |
| pehrhovey | 0:a548a085de55 | 622 | { |
| pehrhovey | 0:a548a085de55 | 623 | /* next octet in next pbuf */ |
| pehrhovey | 0:a548a085de55 | 624 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 625 | if (p == NULL) { return ERR_ARG; } |
| pehrhovey | 0:a548a085de55 | 626 | msg_ptr = p->payload; |
| pehrhovey | 0:a548a085de55 | 627 | plen += p->len; |
| pehrhovey | 0:a548a085de55 | 628 | } |
| pehrhovey | 0:a548a085de55 | 629 | else |
| pehrhovey | 0:a548a085de55 | 630 | { |
| pehrhovey | 0:a548a085de55 | 631 | /* next octet in same pbuf */ |
| pehrhovey | 0:a548a085de55 | 632 | msg_ptr++; |
| pehrhovey | 0:a548a085de55 | 633 | } |
| pehrhovey | 0:a548a085de55 | 634 | } |
| pehrhovey | 0:a548a085de55 | 635 | /* copy last octet */ |
| pehrhovey | 0:a548a085de55 | 636 | *raw = *msg_ptr; |
| pehrhovey | 0:a548a085de55 | 637 | return ERR_OK; |
| pehrhovey | 0:a548a085de55 | 638 | } |
| pehrhovey | 0:a548a085de55 | 639 | else |
| pehrhovey | 0:a548a085de55 | 640 | { |
| pehrhovey | 0:a548a085de55 | 641 | /* raw_len < len, not enough dst space */ |
| pehrhovey | 0:a548a085de55 | 642 | return ERR_ARG; |
| pehrhovey | 0:a548a085de55 | 643 | } |
| pehrhovey | 0:a548a085de55 | 644 | } |
| pehrhovey | 0:a548a085de55 | 645 | p = p->next; |
| pehrhovey | 0:a548a085de55 | 646 | } |
| pehrhovey | 0:a548a085de55 | 647 | /* p == NULL, ofs >= plen */ |
| pehrhovey | 0:a548a085de55 | 648 | return ERR_ARG; |
| pehrhovey | 0:a548a085de55 | 649 | } |
| pehrhovey | 0:a548a085de55 | 650 | else |
| pehrhovey | 0:a548a085de55 | 651 | { |
| pehrhovey | 0:a548a085de55 | 652 | /* len == 0, empty string */ |
| pehrhovey | 0:a548a085de55 | 653 | return ERR_OK; |
| pehrhovey | 0:a548a085de55 | 654 | } |
| pehrhovey | 0:a548a085de55 | 655 | } |
| pehrhovey | 0:a548a085de55 | 656 | |
| pehrhovey | 0:a548a085de55 | 657 | #endif /* LWIP_SNMP */ |