Rod Coleman / NetServSB2

Netservices modded to read fragmented HTTP respsonse/payload from special purpose server - 180 bytes only

lwip/core/snmp/asn1_enc.c@0:850eacf3e945, 2011-09-08 (annotated)

Committer:
RodColeman
Date:
Thu Sep 08 10:48:09 2011 +0000
Revision:
0:850eacf3e945
revised fixed length to 178 bytes

Who changed what in which revision?

UserRevisionLine numberNew contents of line
RodColeman 0:850eacf3e945 1 /**
RodColeman 0:850eacf3e945 2 * @file
RodColeman 0:850eacf3e945 3 * Abstract Syntax Notation One (ISO 8824, 8825) encoding
RodColeman 0:850eacf3e945 4 *
RodColeman 0:850eacf3e945 5 * @todo not optimised (yet), favor correctness over speed, favor speed over size
RodColeman 0:850eacf3e945 6 */
RodColeman 0:850eacf3e945 7
RodColeman 0:850eacf3e945 8 /*
RodColeman 0:850eacf3e945 9 * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
RodColeman 0:850eacf3e945 10 * All rights reserved.
RodColeman 0:850eacf3e945 11 *
RodColeman 0:850eacf3e945 12 * Redistribution and use in source and binary forms, with or without modification,
RodColeman 0:850eacf3e945 13 * are permitted provided that the following conditions are met:
RodColeman 0:850eacf3e945 14 *
RodColeman 0:850eacf3e945 15 * 1. Redistributions of source code must retain the above copyright notice,
RodColeman 0:850eacf3e945 16 * this list of conditions and the following disclaimer.
RodColeman 0:850eacf3e945 17 * 2. Redistributions in binary form must reproduce the above copyright notice,
RodColeman 0:850eacf3e945 18 * this list of conditions and the following disclaimer in the documentation
RodColeman 0:850eacf3e945 19 * and/or other materials provided with the distribution.
RodColeman 0:850eacf3e945 20 * 3. The name of the author may not be used to endorse or promote products
RodColeman 0:850eacf3e945 21 * derived from this software without specific prior written permission.
RodColeman 0:850eacf3e945 22 *
RodColeman 0:850eacf3e945 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
RodColeman 0:850eacf3e945 24 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
RodColeman 0:850eacf3e945 25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
RodColeman 0:850eacf3e945 26 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
RodColeman 0:850eacf3e945 27 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
RodColeman 0:850eacf3e945 28 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
RodColeman 0:850eacf3e945 29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
RodColeman 0:850eacf3e945 30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
RodColeman 0:850eacf3e945 31 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
RodColeman 0:850eacf3e945 32 * OF SUCH DAMAGE.
RodColeman 0:850eacf3e945 33 *
RodColeman 0:850eacf3e945 34 * Author: Christiaan Simons <christiaan.simons@axon.tv>
RodColeman 0:850eacf3e945 35 */
RodColeman 0:850eacf3e945 36
RodColeman 0:850eacf3e945 37 #include "lwip/opt.h"
RodColeman 0:850eacf3e945 38
RodColeman 0:850eacf3e945 39 #if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
RodColeman 0:850eacf3e945 40
RodColeman 0:850eacf3e945 41 #include "lwip/snmp_asn1.h"
RodColeman 0:850eacf3e945 42
RodColeman 0:850eacf3e945 43 /**
RodColeman 0:850eacf3e945 44 * Returns octet count for length.
RodColeman 0:850eacf3e945 45 *
RodColeman 0:850eacf3e945 46 * @param length
RodColeman 0:850eacf3e945 47 * @param octets_needed points to the return value
RodColeman 0:850eacf3e945 48 */
RodColeman 0:850eacf3e945 49 void
RodColeman 0:850eacf3e945 50 snmp_asn1_enc_length_cnt(u16_t length, u8_t *octets_needed)
RodColeman 0:850eacf3e945 51 {
RodColeman 0:850eacf3e945 52 if (length < 0x80U)
RodColeman 0:850eacf3e945 53 {
RodColeman 0:850eacf3e945 54 *octets_needed = 1;
RodColeman 0:850eacf3e945 55 }
RodColeman 0:850eacf3e945 56 else if (length < 0x100U)
RodColeman 0:850eacf3e945 57 {
RodColeman 0:850eacf3e945 58 *octets_needed = 2;
RodColeman 0:850eacf3e945 59 }
RodColeman 0:850eacf3e945 60 else
RodColeman 0:850eacf3e945 61 {
RodColeman 0:850eacf3e945 62 *octets_needed = 3;
RodColeman 0:850eacf3e945 63 }
RodColeman 0:850eacf3e945 64 }
RodColeman 0:850eacf3e945 65
RodColeman 0:850eacf3e945 66 /**
RodColeman 0:850eacf3e945 67 * Returns octet count for an u32_t.
RodColeman 0:850eacf3e945 68 *
RodColeman 0:850eacf3e945 69 * @param value
RodColeman 0:850eacf3e945 70 * @param octets_needed points to the return value
RodColeman 0:850eacf3e945 71 *
RodColeman 0:850eacf3e945 72 * @note ASN coded integers are _always_ signed. E.g. +0xFFFF is coded
RodColeman 0:850eacf3e945 73 * as 0x00,0xFF,0xFF. Note the leading sign octet. A positive value
RodColeman 0:850eacf3e945 74 * of 0xFFFFFFFF is preceded with 0x00 and the length is 5 octets!!
RodColeman 0:850eacf3e945 75 */
RodColeman 0:850eacf3e945 76 void
RodColeman 0:850eacf3e945 77 snmp_asn1_enc_u32t_cnt(u32_t value, u16_t *octets_needed)
RodColeman 0:850eacf3e945 78 {
RodColeman 0:850eacf3e945 79 if (value < 0x80UL)
RodColeman 0:850eacf3e945 80 {
RodColeman 0:850eacf3e945 81 *octets_needed = 1;
RodColeman 0:850eacf3e945 82 }
RodColeman 0:850eacf3e945 83 else if (value < 0x8000UL)
RodColeman 0:850eacf3e945 84 {
RodColeman 0:850eacf3e945 85 *octets_needed = 2;
RodColeman 0:850eacf3e945 86 }
RodColeman 0:850eacf3e945 87 else if (value < 0x800000UL)
RodColeman 0:850eacf3e945 88 {
RodColeman 0:850eacf3e945 89 *octets_needed = 3;
RodColeman 0:850eacf3e945 90 }
RodColeman 0:850eacf3e945 91 else if (value < 0x80000000UL)
RodColeman 0:850eacf3e945 92 {
RodColeman 0:850eacf3e945 93 *octets_needed = 4;
RodColeman 0:850eacf3e945 94 }
RodColeman 0:850eacf3e945 95 else
RodColeman 0:850eacf3e945 96 {
RodColeman 0:850eacf3e945 97 *octets_needed = 5;
RodColeman 0:850eacf3e945 98 }
RodColeman 0:850eacf3e945 99 }
RodColeman 0:850eacf3e945 100
RodColeman 0:850eacf3e945 101 /**
RodColeman 0:850eacf3e945 102 * Returns octet count for an s32_t.
RodColeman 0:850eacf3e945 103 *
RodColeman 0:850eacf3e945 104 * @param value
RodColeman 0:850eacf3e945 105 * @param octets_needed points to the return value
RodColeman 0:850eacf3e945 106 *
RodColeman 0:850eacf3e945 107 * @note ASN coded integers are _always_ signed.
RodColeman 0:850eacf3e945 108 */
RodColeman 0:850eacf3e945 109 void
RodColeman 0:850eacf3e945 110 snmp_asn1_enc_s32t_cnt(s32_t value, u16_t *octets_needed)
RodColeman 0:850eacf3e945 111 {
RodColeman 0:850eacf3e945 112 if (value < 0)
RodColeman 0:850eacf3e945 113 {
RodColeman 0:850eacf3e945 114 value = ~value;
RodColeman 0:850eacf3e945 115 }
RodColeman 0:850eacf3e945 116 if (value < 0x80L)
RodColeman 0:850eacf3e945 117 {
RodColeman 0:850eacf3e945 118 *octets_needed = 1;
RodColeman 0:850eacf3e945 119 }
RodColeman 0:850eacf3e945 120 else if (value < 0x8000L)
RodColeman 0:850eacf3e945 121 {
RodColeman 0:850eacf3e945 122 *octets_needed = 2;
RodColeman 0:850eacf3e945 123 }
RodColeman 0:850eacf3e945 124 else if (value < 0x800000L)
RodColeman 0:850eacf3e945 125 {
RodColeman 0:850eacf3e945 126 *octets_needed = 3;
RodColeman 0:850eacf3e945 127 }
RodColeman 0:850eacf3e945 128 else
RodColeman 0:850eacf3e945 129 {
RodColeman 0:850eacf3e945 130 *octets_needed = 4;
RodColeman 0:850eacf3e945 131 }
RodColeman 0:850eacf3e945 132 }
RodColeman 0:850eacf3e945 133
RodColeman 0:850eacf3e945 134 /**
RodColeman 0:850eacf3e945 135 * Returns octet count for an object identifier.
RodColeman 0:850eacf3e945 136 *
RodColeman 0:850eacf3e945 137 * @param ident_len object identifier array length
RodColeman 0:850eacf3e945 138 * @param ident points to object identifier array
RodColeman 0:850eacf3e945 139 * @param octets_needed points to the return value
RodColeman 0:850eacf3e945 140 */
RodColeman 0:850eacf3e945 141 void
RodColeman 0:850eacf3e945 142 snmp_asn1_enc_oid_cnt(u8_t ident_len, s32_t *ident, u16_t *octets_needed)
RodColeman 0:850eacf3e945 143 {
RodColeman 0:850eacf3e945 144 s32_t sub_id;
RodColeman 0:850eacf3e945 145 u8_t cnt;
RodColeman 0:850eacf3e945 146
RodColeman 0:850eacf3e945 147 cnt = 0;
RodColeman 0:850eacf3e945 148 if (ident_len > 1)
RodColeman 0:850eacf3e945 149 {
RodColeman 0:850eacf3e945 150 /* compressed prefix in one octet */
RodColeman 0:850eacf3e945 151 cnt++;
RodColeman 0:850eacf3e945 152 ident_len -= 2;
RodColeman 0:850eacf3e945 153 ident += 2;
RodColeman 0:850eacf3e945 154 }
RodColeman 0:850eacf3e945 155 while(ident_len > 0)
RodColeman 0:850eacf3e945 156 {
RodColeman 0:850eacf3e945 157 ident_len--;
RodColeman 0:850eacf3e945 158 sub_id = *ident;
RodColeman 0:850eacf3e945 159
RodColeman 0:850eacf3e945 160 sub_id >>= 7;
RodColeman 0:850eacf3e945 161 cnt++;
RodColeman 0:850eacf3e945 162 while(sub_id > 0)
RodColeman 0:850eacf3e945 163 {
RodColeman 0:850eacf3e945 164 sub_id >>= 7;
RodColeman 0:850eacf3e945 165 cnt++;
RodColeman 0:850eacf3e945 166 }
RodColeman 0:850eacf3e945 167 ident++;
RodColeman 0:850eacf3e945 168 }
RodColeman 0:850eacf3e945 169 *octets_needed = cnt;
RodColeman 0:850eacf3e945 170 }
RodColeman 0:850eacf3e945 171
RodColeman 0:850eacf3e945 172 /**
RodColeman 0:850eacf3e945 173 * Encodes ASN type field into a pbuf chained ASN1 msg.
RodColeman 0:850eacf3e945 174 *
RodColeman 0:850eacf3e945 175 * @param p points to output pbuf to encode value into
RodColeman 0:850eacf3e945 176 * @param ofs points to the offset within the pbuf chain
RodColeman 0:850eacf3e945 177 * @param type input ASN1 type
RodColeman 0:850eacf3e945 178 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
RodColeman 0:850eacf3e945 179 */
RodColeman 0:850eacf3e945 180 err_t
RodColeman 0:850eacf3e945 181 snmp_asn1_enc_type(struct pbuf *p, u16_t ofs, u8_t type)
RodColeman 0:850eacf3e945 182 {
RodColeman 0:850eacf3e945 183 u16_t plen, base;
RodColeman 0:850eacf3e945 184 u8_t *msg_ptr;
RodColeman 0:850eacf3e945 185
RodColeman 0:850eacf3e945 186 plen = 0;
RodColeman 0:850eacf3e945 187 while (p != NULL)
RodColeman 0:850eacf3e945 188 {
RodColeman 0:850eacf3e945 189 base = plen;
RodColeman 0:850eacf3e945 190 plen += p->len;
RodColeman 0:850eacf3e945 191 if (ofs < plen)
RodColeman 0:850eacf3e945 192 {
RodColeman 0:850eacf3e945 193 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 194 msg_ptr += ofs - base;
RodColeman 0:850eacf3e945 195 *msg_ptr = type;
RodColeman 0:850eacf3e945 196 return ERR_OK;
RodColeman 0:850eacf3e945 197 }
RodColeman 0:850eacf3e945 198 p = p->next;
RodColeman 0:850eacf3e945 199 }
RodColeman 0:850eacf3e945 200 /* p == NULL, ofs >= plen */
RodColeman 0:850eacf3e945 201 return ERR_ARG;
RodColeman 0:850eacf3e945 202 }
RodColeman 0:850eacf3e945 203
RodColeman 0:850eacf3e945 204 /**
RodColeman 0:850eacf3e945 205 * Encodes host order length field into a pbuf chained ASN1 msg.
RodColeman 0:850eacf3e945 206 *
RodColeman 0:850eacf3e945 207 * @param p points to output pbuf to encode length into
RodColeman 0:850eacf3e945 208 * @param ofs points to the offset within the pbuf chain
RodColeman 0:850eacf3e945 209 * @param length is the host order length to be encoded
RodColeman 0:850eacf3e945 210 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
RodColeman 0:850eacf3e945 211 */
RodColeman 0:850eacf3e945 212 err_t
RodColeman 0:850eacf3e945 213 snmp_asn1_enc_length(struct pbuf *p, u16_t ofs, u16_t length)
RodColeman 0:850eacf3e945 214 {
RodColeman 0:850eacf3e945 215 u16_t plen, base;
RodColeman 0:850eacf3e945 216 u8_t *msg_ptr;
RodColeman 0:850eacf3e945 217
RodColeman 0:850eacf3e945 218 plen = 0;
RodColeman 0:850eacf3e945 219 while (p != NULL)
RodColeman 0:850eacf3e945 220 {
RodColeman 0:850eacf3e945 221 base = plen;
RodColeman 0:850eacf3e945 222 plen += p->len;
RodColeman 0:850eacf3e945 223 if (ofs < plen)
RodColeman 0:850eacf3e945 224 {
RodColeman 0:850eacf3e945 225 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 226 msg_ptr += ofs - base;
RodColeman 0:850eacf3e945 227
RodColeman 0:850eacf3e945 228 if (length < 0x80)
RodColeman 0:850eacf3e945 229 {
RodColeman 0:850eacf3e945 230 *msg_ptr = (u8_t)length;
RodColeman 0:850eacf3e945 231 return ERR_OK;
RodColeman 0:850eacf3e945 232 }
RodColeman 0:850eacf3e945 233 else if (length < 0x100)
RodColeman 0:850eacf3e945 234 {
RodColeman 0:850eacf3e945 235 *msg_ptr = 0x81;
RodColeman 0:850eacf3e945 236 ofs += 1;
RodColeman 0:850eacf3e945 237 if (ofs >= plen)
RodColeman 0:850eacf3e945 238 {
RodColeman 0:850eacf3e945 239 /* next octet in next pbuf */
RodColeman 0:850eacf3e945 240 p = p->next;
RodColeman 0:850eacf3e945 241 if (p == NULL) { return ERR_ARG; }
RodColeman 0:850eacf3e945 242 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 243 }
RodColeman 0:850eacf3e945 244 else
RodColeman 0:850eacf3e945 245 {
RodColeman 0:850eacf3e945 246 /* next octet in same pbuf */
RodColeman 0:850eacf3e945 247 msg_ptr++;
RodColeman 0:850eacf3e945 248 }
RodColeman 0:850eacf3e945 249 *msg_ptr = (u8_t)length;
RodColeman 0:850eacf3e945 250 return ERR_OK;
RodColeman 0:850eacf3e945 251 }
RodColeman 0:850eacf3e945 252 else
RodColeman 0:850eacf3e945 253 {
RodColeman 0:850eacf3e945 254 u8_t i;
RodColeman 0:850eacf3e945 255
RodColeman 0:850eacf3e945 256 /* length >= 0x100 && length <= 0xFFFF */
RodColeman 0:850eacf3e945 257 *msg_ptr = 0x82;
RodColeman 0:850eacf3e945 258 i = 2;
RodColeman 0:850eacf3e945 259 while (i > 0)
RodColeman 0:850eacf3e945 260 {
RodColeman 0:850eacf3e945 261 i--;
RodColeman 0:850eacf3e945 262 ofs += 1;
RodColeman 0:850eacf3e945 263 if (ofs >= plen)
RodColeman 0:850eacf3e945 264 {
RodColeman 0:850eacf3e945 265 /* next octet in next pbuf */
RodColeman 0:850eacf3e945 266 p = p->next;
RodColeman 0:850eacf3e945 267 if (p == NULL) { return ERR_ARG; }
RodColeman 0:850eacf3e945 268 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 269 plen += p->len;
RodColeman 0:850eacf3e945 270 }
RodColeman 0:850eacf3e945 271 else
RodColeman 0:850eacf3e945 272 {
RodColeman 0:850eacf3e945 273 /* next octet in same pbuf */
RodColeman 0:850eacf3e945 274 msg_ptr++;
RodColeman 0:850eacf3e945 275 }
RodColeman 0:850eacf3e945 276 if (i == 0)
RodColeman 0:850eacf3e945 277 {
RodColeman 0:850eacf3e945 278 /* least significant length octet */
RodColeman 0:850eacf3e945 279 *msg_ptr = (u8_t)length;
RodColeman 0:850eacf3e945 280 }
RodColeman 0:850eacf3e945 281 else
RodColeman 0:850eacf3e945 282 {
RodColeman 0:850eacf3e945 283 /* most significant length octet */
RodColeman 0:850eacf3e945 284 *msg_ptr = (u8_t)(length >> 8);
RodColeman 0:850eacf3e945 285 }
RodColeman 0:850eacf3e945 286 }
RodColeman 0:850eacf3e945 287 return ERR_OK;
RodColeman 0:850eacf3e945 288 }
RodColeman 0:850eacf3e945 289 }
RodColeman 0:850eacf3e945 290 p = p->next;
RodColeman 0:850eacf3e945 291 }
RodColeman 0:850eacf3e945 292 /* p == NULL, ofs >= plen */
RodColeman 0:850eacf3e945 293 return ERR_ARG;
RodColeman 0:850eacf3e945 294 }
RodColeman 0:850eacf3e945 295
RodColeman 0:850eacf3e945 296 /**
RodColeman 0:850eacf3e945 297 * Encodes u32_t (counter, gauge, timeticks) into a pbuf chained ASN1 msg.
RodColeman 0:850eacf3e945 298 *
RodColeman 0:850eacf3e945 299 * @param p points to output pbuf to encode value into
RodColeman 0:850eacf3e945 300 * @param ofs points to the offset within the pbuf chain
RodColeman 0:850eacf3e945 301 * @param octets_needed encoding length (from snmp_asn1_enc_u32t_cnt())
RodColeman 0:850eacf3e945 302 * @param value is the host order u32_t value to be encoded
RodColeman 0:850eacf3e945 303 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
RodColeman 0:850eacf3e945 304 *
RodColeman 0:850eacf3e945 305 * @see snmp_asn1_enc_u32t_cnt()
RodColeman 0:850eacf3e945 306 */
RodColeman 0:850eacf3e945 307 err_t
RodColeman 0:850eacf3e945 308 snmp_asn1_enc_u32t(struct pbuf *p, u16_t ofs, u16_t octets_needed, u32_t value)
RodColeman 0:850eacf3e945 309 {
RodColeman 0:850eacf3e945 310 u16_t plen, base;
RodColeman 0:850eacf3e945 311 u8_t *msg_ptr;
RodColeman 0:850eacf3e945 312
RodColeman 0:850eacf3e945 313 plen = 0;
RodColeman 0:850eacf3e945 314 while (p != NULL)
RodColeman 0:850eacf3e945 315 {
RodColeman 0:850eacf3e945 316 base = plen;
RodColeman 0:850eacf3e945 317 plen += p->len;
RodColeman 0:850eacf3e945 318 if (ofs < plen)
RodColeman 0:850eacf3e945 319 {
RodColeman 0:850eacf3e945 320 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 321 msg_ptr += ofs - base;
RodColeman 0:850eacf3e945 322
RodColeman 0:850eacf3e945 323 if (octets_needed == 5)
RodColeman 0:850eacf3e945 324 {
RodColeman 0:850eacf3e945 325 /* not enough bits in 'value' add leading 0x00 */
RodColeman 0:850eacf3e945 326 octets_needed--;
RodColeman 0:850eacf3e945 327 *msg_ptr = 0x00;
RodColeman 0:850eacf3e945 328 ofs += 1;
RodColeman 0:850eacf3e945 329 if (ofs >= plen)
RodColeman 0:850eacf3e945 330 {
RodColeman 0:850eacf3e945 331 /* next octet in next pbuf */
RodColeman 0:850eacf3e945 332 p = p->next;
RodColeman 0:850eacf3e945 333 if (p == NULL) { return ERR_ARG; }
RodColeman 0:850eacf3e945 334 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 335 plen += p->len;
RodColeman 0:850eacf3e945 336 }
RodColeman 0:850eacf3e945 337 else
RodColeman 0:850eacf3e945 338 {
RodColeman 0:850eacf3e945 339 /* next octet in same pbuf */
RodColeman 0:850eacf3e945 340 msg_ptr++;
RodColeman 0:850eacf3e945 341 }
RodColeman 0:850eacf3e945 342 }
RodColeman 0:850eacf3e945 343 while (octets_needed > 1)
RodColeman 0:850eacf3e945 344 {
RodColeman 0:850eacf3e945 345 octets_needed--;
RodColeman 0:850eacf3e945 346 *msg_ptr = (u8_t)(value >> (octets_needed << 3));
RodColeman 0:850eacf3e945 347 ofs += 1;
RodColeman 0:850eacf3e945 348 if (ofs >= plen)
RodColeman 0:850eacf3e945 349 {
RodColeman 0:850eacf3e945 350 /* next octet in next pbuf */
RodColeman 0:850eacf3e945 351 p = p->next;
RodColeman 0:850eacf3e945 352 if (p == NULL) { return ERR_ARG; }
RodColeman 0:850eacf3e945 353 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 354 plen += p->len;
RodColeman 0:850eacf3e945 355 }
RodColeman 0:850eacf3e945 356 else
RodColeman 0:850eacf3e945 357 {
RodColeman 0:850eacf3e945 358 /* next octet in same pbuf */
RodColeman 0:850eacf3e945 359 msg_ptr++;
RodColeman 0:850eacf3e945 360 }
RodColeman 0:850eacf3e945 361 }
RodColeman 0:850eacf3e945 362 /* (only) one least significant octet */
RodColeman 0:850eacf3e945 363 *msg_ptr = (u8_t)value;
RodColeman 0:850eacf3e945 364 return ERR_OK;
RodColeman 0:850eacf3e945 365 }
RodColeman 0:850eacf3e945 366 p = p->next;
RodColeman 0:850eacf3e945 367 }
RodColeman 0:850eacf3e945 368 /* p == NULL, ofs >= plen */
RodColeman 0:850eacf3e945 369 return ERR_ARG;
RodColeman 0:850eacf3e945 370 }
RodColeman 0:850eacf3e945 371
RodColeman 0:850eacf3e945 372 /**
RodColeman 0:850eacf3e945 373 * Encodes s32_t integer into a pbuf chained ASN1 msg.
RodColeman 0:850eacf3e945 374 *
RodColeman 0:850eacf3e945 375 * @param p points to output pbuf to encode value into
RodColeman 0:850eacf3e945 376 * @param ofs points to the offset within the pbuf chain
RodColeman 0:850eacf3e945 377 * @param octets_needed encoding length (from snmp_asn1_enc_s32t_cnt())
RodColeman 0:850eacf3e945 378 * @param value is the host order s32_t value to be encoded
RodColeman 0:850eacf3e945 379 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
RodColeman 0:850eacf3e945 380 *
RodColeman 0:850eacf3e945 381 * @see snmp_asn1_enc_s32t_cnt()
RodColeman 0:850eacf3e945 382 */
RodColeman 0:850eacf3e945 383 err_t
RodColeman 0:850eacf3e945 384 snmp_asn1_enc_s32t(struct pbuf *p, u16_t ofs, u16_t octets_needed, s32_t value)
RodColeman 0:850eacf3e945 385 {
RodColeman 0:850eacf3e945 386 u16_t plen, base;
RodColeman 0:850eacf3e945 387 u8_t *msg_ptr;
RodColeman 0:850eacf3e945 388
RodColeman 0:850eacf3e945 389 plen = 0;
RodColeman 0:850eacf3e945 390 while (p != NULL)
RodColeman 0:850eacf3e945 391 {
RodColeman 0:850eacf3e945 392 base = plen;
RodColeman 0:850eacf3e945 393 plen += p->len;
RodColeman 0:850eacf3e945 394 if (ofs < plen)
RodColeman 0:850eacf3e945 395 {
RodColeman 0:850eacf3e945 396 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 397 msg_ptr += ofs - base;
RodColeman 0:850eacf3e945 398
RodColeman 0:850eacf3e945 399 while (octets_needed > 1)
RodColeman 0:850eacf3e945 400 {
RodColeman 0:850eacf3e945 401 octets_needed--;
RodColeman 0:850eacf3e945 402 *msg_ptr = (u8_t)(value >> (octets_needed << 3));
RodColeman 0:850eacf3e945 403 ofs += 1;
RodColeman 0:850eacf3e945 404 if (ofs >= plen)
RodColeman 0:850eacf3e945 405 {
RodColeman 0:850eacf3e945 406 /* next octet in next pbuf */
RodColeman 0:850eacf3e945 407 p = p->next;
RodColeman 0:850eacf3e945 408 if (p == NULL) { return ERR_ARG; }
RodColeman 0:850eacf3e945 409 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 410 plen += p->len;
RodColeman 0:850eacf3e945 411 }
RodColeman 0:850eacf3e945 412 else
RodColeman 0:850eacf3e945 413 {
RodColeman 0:850eacf3e945 414 /* next octet in same pbuf */
RodColeman 0:850eacf3e945 415 msg_ptr++;
RodColeman 0:850eacf3e945 416 }
RodColeman 0:850eacf3e945 417 }
RodColeman 0:850eacf3e945 418 /* (only) one least significant octet */
RodColeman 0:850eacf3e945 419 *msg_ptr = (u8_t)value;
RodColeman 0:850eacf3e945 420 return ERR_OK;
RodColeman 0:850eacf3e945 421 }
RodColeman 0:850eacf3e945 422 p = p->next;
RodColeman 0:850eacf3e945 423 }
RodColeman 0:850eacf3e945 424 /* p == NULL, ofs >= plen */
RodColeman 0:850eacf3e945 425 return ERR_ARG;
RodColeman 0:850eacf3e945 426 }
RodColeman 0:850eacf3e945 427
RodColeman 0:850eacf3e945 428 /**
RodColeman 0:850eacf3e945 429 * Encodes object identifier into a pbuf chained ASN1 msg.
RodColeman 0:850eacf3e945 430 *
RodColeman 0:850eacf3e945 431 * @param p points to output pbuf to encode oid into
RodColeman 0:850eacf3e945 432 * @param ofs points to the offset within the pbuf chain
RodColeman 0:850eacf3e945 433 * @param ident_len object identifier array length
RodColeman 0:850eacf3e945 434 * @param ident points to object identifier array
RodColeman 0:850eacf3e945 435 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
RodColeman 0:850eacf3e945 436 */
RodColeman 0:850eacf3e945 437 err_t
RodColeman 0:850eacf3e945 438 snmp_asn1_enc_oid(struct pbuf *p, u16_t ofs, u8_t ident_len, s32_t *ident)
RodColeman 0:850eacf3e945 439 {
RodColeman 0:850eacf3e945 440 u16_t plen, base;
RodColeman 0:850eacf3e945 441 u8_t *msg_ptr;
RodColeman 0:850eacf3e945 442
RodColeman 0:850eacf3e945 443 plen = 0;
RodColeman 0:850eacf3e945 444 while (p != NULL)
RodColeman 0:850eacf3e945 445 {
RodColeman 0:850eacf3e945 446 base = plen;
RodColeman 0:850eacf3e945 447 plen += p->len;
RodColeman 0:850eacf3e945 448 if (ofs < plen)
RodColeman 0:850eacf3e945 449 {
RodColeman 0:850eacf3e945 450 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 451 msg_ptr += ofs - base;
RodColeman 0:850eacf3e945 452
RodColeman 0:850eacf3e945 453 if (ident_len > 1)
RodColeman 0:850eacf3e945 454 {
RodColeman 0:850eacf3e945 455 if ((ident[0] == 1) && (ident[1] == 3))
RodColeman 0:850eacf3e945 456 {
RodColeman 0:850eacf3e945 457 /* compressed (most common) prefix .iso.org */
RodColeman 0:850eacf3e945 458 *msg_ptr = 0x2b;
RodColeman 0:850eacf3e945 459 }
RodColeman 0:850eacf3e945 460 else
RodColeman 0:850eacf3e945 461 {
RodColeman 0:850eacf3e945 462 /* calculate prefix */
RodColeman 0:850eacf3e945 463 *msg_ptr = (u8_t)((ident[0] * 40) + ident[1]);
RodColeman 0:850eacf3e945 464 }
RodColeman 0:850eacf3e945 465 ofs += 1;
RodColeman 0:850eacf3e945 466 if (ofs >= plen)
RodColeman 0:850eacf3e945 467 {
RodColeman 0:850eacf3e945 468 /* next octet in next pbuf */
RodColeman 0:850eacf3e945 469 p = p->next;
RodColeman 0:850eacf3e945 470 if (p == NULL) { return ERR_ARG; }
RodColeman 0:850eacf3e945 471 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 472 plen += p->len;
RodColeman 0:850eacf3e945 473 }
RodColeman 0:850eacf3e945 474 else
RodColeman 0:850eacf3e945 475 {
RodColeman 0:850eacf3e945 476 /* next octet in same pbuf */
RodColeman 0:850eacf3e945 477 msg_ptr++;
RodColeman 0:850eacf3e945 478 }
RodColeman 0:850eacf3e945 479 ident_len -= 2;
RodColeman 0:850eacf3e945 480 ident += 2;
RodColeman 0:850eacf3e945 481 }
RodColeman 0:850eacf3e945 482 else
RodColeman 0:850eacf3e945 483 {
RodColeman 0:850eacf3e945 484 /* @bug: allow empty varbinds for symmetry (we must decode them for getnext), allow partial compression?? */
RodColeman 0:850eacf3e945 485 /* ident_len <= 1, at least we need zeroDotZero (0.0) (ident_len == 2) */
RodColeman 0:850eacf3e945 486 return ERR_ARG;
RodColeman 0:850eacf3e945 487 }
RodColeman 0:850eacf3e945 488 while (ident_len > 0)
RodColeman 0:850eacf3e945 489 {
RodColeman 0:850eacf3e945 490 s32_t sub_id;
RodColeman 0:850eacf3e945 491 u8_t shift, tail;
RodColeman 0:850eacf3e945 492
RodColeman 0:850eacf3e945 493 ident_len--;
RodColeman 0:850eacf3e945 494 sub_id = *ident;
RodColeman 0:850eacf3e945 495 tail = 0;
RodColeman 0:850eacf3e945 496 shift = 28;
RodColeman 0:850eacf3e945 497 while(shift > 0)
RodColeman 0:850eacf3e945 498 {
RodColeman 0:850eacf3e945 499 u8_t code;
RodColeman 0:850eacf3e945 500
RodColeman 0:850eacf3e945 501 code = (u8_t)(sub_id >> shift);
RodColeman 0:850eacf3e945 502 if ((code != 0) || (tail != 0))
RodColeman 0:850eacf3e945 503 {
RodColeman 0:850eacf3e945 504 tail = 1;
RodColeman 0:850eacf3e945 505 *msg_ptr = code | 0x80;
RodColeman 0:850eacf3e945 506 ofs += 1;
RodColeman 0:850eacf3e945 507 if (ofs >= plen)
RodColeman 0:850eacf3e945 508 {
RodColeman 0:850eacf3e945 509 /* next octet in next pbuf */
RodColeman 0:850eacf3e945 510 p = p->next;
RodColeman 0:850eacf3e945 511 if (p == NULL) { return ERR_ARG; }
RodColeman 0:850eacf3e945 512 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 513 plen += p->len;
RodColeman 0:850eacf3e945 514 }
RodColeman 0:850eacf3e945 515 else
RodColeman 0:850eacf3e945 516 {
RodColeman 0:850eacf3e945 517 /* next octet in same pbuf */
RodColeman 0:850eacf3e945 518 msg_ptr++;
RodColeman 0:850eacf3e945 519 }
RodColeman 0:850eacf3e945 520 }
RodColeman 0:850eacf3e945 521 shift -= 7;
RodColeman 0:850eacf3e945 522 }
RodColeman 0:850eacf3e945 523 *msg_ptr = (u8_t)sub_id & 0x7F;
RodColeman 0:850eacf3e945 524 if (ident_len > 0)
RodColeman 0:850eacf3e945 525 {
RodColeman 0:850eacf3e945 526 ofs += 1;
RodColeman 0:850eacf3e945 527 if (ofs >= plen)
RodColeman 0:850eacf3e945 528 {
RodColeman 0:850eacf3e945 529 /* next octet in next pbuf */
RodColeman 0:850eacf3e945 530 p = p->next;
RodColeman 0:850eacf3e945 531 if (p == NULL) { return ERR_ARG; }
RodColeman 0:850eacf3e945 532 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 533 plen += p->len;
RodColeman 0:850eacf3e945 534 }
RodColeman 0:850eacf3e945 535 else
RodColeman 0:850eacf3e945 536 {
RodColeman 0:850eacf3e945 537 /* next octet in same pbuf */
RodColeman 0:850eacf3e945 538 msg_ptr++;
RodColeman 0:850eacf3e945 539 }
RodColeman 0:850eacf3e945 540 }
RodColeman 0:850eacf3e945 541 /* proceed to next sub-identifier */
RodColeman 0:850eacf3e945 542 ident++;
RodColeman 0:850eacf3e945 543 }
RodColeman 0:850eacf3e945 544 return ERR_OK;
RodColeman 0:850eacf3e945 545 }
RodColeman 0:850eacf3e945 546 p = p->next;
RodColeman 0:850eacf3e945 547 }
RodColeman 0:850eacf3e945 548 /* p == NULL, ofs >= plen */
RodColeman 0:850eacf3e945 549 return ERR_ARG;
RodColeman 0:850eacf3e945 550 }
RodColeman 0:850eacf3e945 551
RodColeman 0:850eacf3e945 552 /**
RodColeman 0:850eacf3e945 553 * Encodes raw data (octet string, opaque) into a pbuf chained ASN1 msg.
RodColeman 0:850eacf3e945 554 *
RodColeman 0:850eacf3e945 555 * @param p points to output pbuf to encode raw data into
RodColeman 0:850eacf3e945 556 * @param ofs points to the offset within the pbuf chain
RodColeman 0:850eacf3e945 557 * @param raw_len raw data length
RodColeman 0:850eacf3e945 558 * @param raw points raw data
RodColeman 0:850eacf3e945 559 * @return ERR_OK if successfull, ERR_ARG if we can't (or won't) encode
RodColeman 0:850eacf3e945 560 */
RodColeman 0:850eacf3e945 561 err_t
RodColeman 0:850eacf3e945 562 snmp_asn1_enc_raw(struct pbuf *p, u16_t ofs, u16_t raw_len, u8_t *raw)
RodColeman 0:850eacf3e945 563 {
RodColeman 0:850eacf3e945 564 u16_t plen, base;
RodColeman 0:850eacf3e945 565 u8_t *msg_ptr;
RodColeman 0:850eacf3e945 566
RodColeman 0:850eacf3e945 567 plen = 0;
RodColeman 0:850eacf3e945 568 while (p != NULL)
RodColeman 0:850eacf3e945 569 {
RodColeman 0:850eacf3e945 570 base = plen;
RodColeman 0:850eacf3e945 571 plen += p->len;
RodColeman 0:850eacf3e945 572 if (ofs < plen)
RodColeman 0:850eacf3e945 573 {
RodColeman 0:850eacf3e945 574 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 575 msg_ptr += ofs - base;
RodColeman 0:850eacf3e945 576
RodColeman 0:850eacf3e945 577 while (raw_len > 1)
RodColeman 0:850eacf3e945 578 {
RodColeman 0:850eacf3e945 579 /* copy raw_len - 1 octets */
RodColeman 0:850eacf3e945 580 raw_len--;
RodColeman 0:850eacf3e945 581 *msg_ptr = *raw;
RodColeman 0:850eacf3e945 582 raw++;
RodColeman 0:850eacf3e945 583 ofs += 1;
RodColeman 0:850eacf3e945 584 if (ofs >= plen)
RodColeman 0:850eacf3e945 585 {
RodColeman 0:850eacf3e945 586 /* next octet in next pbuf */
RodColeman 0:850eacf3e945 587 p = p->next;
RodColeman 0:850eacf3e945 588 if (p == NULL) { return ERR_ARG; }
RodColeman 0:850eacf3e945 589 msg_ptr = (u8_t*)p->payload;
RodColeman 0:850eacf3e945 590 plen += p->len;
RodColeman 0:850eacf3e945 591 }
RodColeman 0:850eacf3e945 592 else
RodColeman 0:850eacf3e945 593 {
RodColeman 0:850eacf3e945 594 /* next octet in same pbuf */
RodColeman 0:850eacf3e945 595 msg_ptr++;
RodColeman 0:850eacf3e945 596 }
RodColeman 0:850eacf3e945 597 }
RodColeman 0:850eacf3e945 598 if (raw_len > 0)
RodColeman 0:850eacf3e945 599 {
RodColeman 0:850eacf3e945 600 /* copy last or single octet */
RodColeman 0:850eacf3e945 601 *msg_ptr = *raw;
RodColeman 0:850eacf3e945 602 }
RodColeman 0:850eacf3e945 603 return ERR_OK;
RodColeman 0:850eacf3e945 604 }
RodColeman 0:850eacf3e945 605 p = p->next;
RodColeman 0:850eacf3e945 606 }
RodColeman 0:850eacf3e945 607 /* p == NULL, ofs >= plen */
RodColeman 0:850eacf3e945 608 return ERR_ARG;
RodColeman 0:850eacf3e945 609 }
RodColeman 0:850eacf3e945 610
RodColeman 0:850eacf3e945 611 #endif /* LWIP_SNMP */