1 /** 2 * @file 3 * SNMP Agent message handling structures. 4 */ 5 6 /* 7 * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands. 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without modification, 11 * are permitted provided that the following conditions are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright notice, 14 * this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 3. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 22 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 23 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 24 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 26 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 29 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 30 * OF SUCH DAMAGE. 31 * 32 * Author: Christiaan Simons <christiaan.simons (at) axon.tv> 33 */ 34 35 #ifndef __LWIP_SNMP_MSG_H__ 36 #define __LWIP_SNMP_MSG_H__ 37 38 #include "lwip/opt.h" 39 #include "lwip/snmp.h" 40 #include "lwip/snmp_structs.h" 41 #include "lwip/ip_addr.h" 42 #include "lwip/err.h" 43 44 #if LWIP_SNMP 45 46 #if SNMP_PRIVATE_MIB 47 /* When using a private MIB, you have to create a file 'private_mib.h' that contains 48 * a 'struct mib_array_node mib_private' which contains your MIB. */ 49 #include "private_mib.h" 50 #endif 51 52 #ifdef __cplusplus 53 extern "C" { 54 #endif 55 56 /* The listen port of the SNMP agent. Clients have to make their requests to 57 this port. Most standard clients won't work if you change this! */ 58 #ifndef SNMP_IN_PORT 59 #define SNMP_IN_PORT 161 60 #endif 61 /* The remote port the SNMP agent sends traps to. Most standard trap sinks won't 62 work if you change this! */ 63 #ifndef SNMP_TRAP_PORT 64 #define SNMP_TRAP_PORT 162 65 #endif 66 67 #define SNMP_ES_NOERROR 0 68 #define SNMP_ES_TOOBIG 1 69 #define SNMP_ES_NOSUCHNAME 2 70 #define SNMP_ES_BADVALUE 3 71 #define SNMP_ES_READONLY 4 72 #define SNMP_ES_GENERROR 5 73 74 #define SNMP_GENTRAP_COLDSTART 0 75 #define SNMP_GENTRAP_WARMSTART 1 76 #define SNMP_GENTRAP_AUTHFAIL 4 77 #define SNMP_GENTRAP_ENTERPRISESPC 6 78 79 struct snmp_varbind 80 { 81 /* next pointer, NULL for last in list */ 82 struct snmp_varbind *next; 83 /* previous pointer, NULL for first in list */ 84 struct snmp_varbind *prev; 85 86 /* object identifier length (in s32_t) */ 87 u8_t ident_len; 88 /* object identifier array */ 89 s32_t *ident; 90 91 /* object value ASN1 type */ 92 u8_t value_type; 93 /* object value length (in u8_t) */ 94 u8_t value_len; 95 /* object value */ 96 void *value; 97 98 /* encoding varbind seq length length */ 99 u8_t seqlenlen; 100 /* encoding object identifier length length */ 101 u8_t olenlen; 102 /* encoding object value length length */ 103 u8_t vlenlen; 104 /* encoding varbind seq length */ 105 u16_t seqlen; 106 /* encoding object identifier length */ 107 u16_t olen; 108 /* encoding object value length */ 109 u16_t vlen; 110 }; 111 112 struct snmp_varbind_root 113 { 114 struct snmp_varbind *head; 115 struct snmp_varbind *tail; 116 /* number of variable bindings in list */ 117 u8_t count; 118 /* encoding varbind-list seq length length */ 119 u8_t seqlenlen; 120 /* encoding varbind-list seq length */ 121 u16_t seqlen; 122 }; 123 124 /** output response message header length fields */ 125 struct snmp_resp_header_lengths 126 { 127 /* encoding error-index length length */ 128 u8_t erridxlenlen; 129 /* encoding error-status length length */ 130 u8_t errstatlenlen; 131 /* encoding request id length length */ 132 u8_t ridlenlen; 133 /* encoding pdu length length */ 134 u8_t pdulenlen; 135 /* encoding community length length */ 136 u8_t comlenlen; 137 /* encoding version length length */ 138 u8_t verlenlen; 139 /* encoding sequence length length */ 140 u8_t seqlenlen; 141 142 /* encoding error-index length */ 143 u16_t erridxlen; 144 /* encoding error-status length */ 145 u16_t errstatlen; 146 /* encoding request id length */ 147 u16_t ridlen; 148 /* encoding pdu length */ 149 u16_t pdulen; 150 /* encoding community length */ 151 u16_t comlen; 152 /* encoding version length */ 153 u16_t verlen; 154 /* encoding sequence length */ 155 u16_t seqlen; 156 }; 157 158 /** output response message header length fields */ 159 struct snmp_trap_header_lengths 160 { 161 /* encoding timestamp length length */ 162 u8_t tslenlen; 163 /* encoding specific-trap length length */ 164 u8_t strplenlen; 165 /* encoding generic-trap length length */ 166 u8_t gtrplenlen; 167 /* encoding agent-addr length length */ 168 u8_t aaddrlenlen; 169 /* encoding enterprise-id length length */ 170 u8_t eidlenlen; 171 /* encoding pdu length length */ 172 u8_t pdulenlen; 173 /* encoding community length length */ 174 u8_t comlenlen; 175 /* encoding version length length */ 176 u8_t verlenlen; 177 /* encoding sequence length length */ 178 u8_t seqlenlen; 179 180 /* encoding timestamp length */ 181 u16_t tslen; 182 /* encoding specific-trap length */ 183 u16_t strplen; 184 /* encoding generic-trap length */ 185 u16_t gtrplen; 186 /* encoding agent-addr length */ 187 u16_t aaddrlen; 188 /* encoding enterprise-id length */ 189 u16_t eidlen; 190 /* encoding pdu length */ 191 u16_t pdulen; 192 /* encoding community length */ 193 u16_t comlen; 194 /* encoding version length */ 195 u16_t verlen; 196 /* encoding sequence length */ 197 u16_t seqlen; 198 }; 199 200 /* Accepting new SNMP messages. */ 201 #define SNMP_MSG_EMPTY 0 202 /* Search for matching object for variable binding. */ 203 #define SNMP_MSG_SEARCH_OBJ 1 204 /* Perform SNMP operation on in-memory object. 205 Pass-through states, for symmetry only. */ 206 #define SNMP_MSG_INTERNAL_GET_OBJDEF 2 207 #define SNMP_MSG_INTERNAL_GET_VALUE 3 208 #define SNMP_MSG_INTERNAL_SET_TEST 4 209 #define SNMP_MSG_INTERNAL_GET_OBJDEF_S 5 210 #define SNMP_MSG_INTERNAL_SET_VALUE 6 211 /* Perform SNMP operation on object located externally. 212 In theory this could be used for building a proxy agent. 213 Practical use is for an enterprise spc. app. gateway. */ 214 #define SNMP_MSG_EXTERNAL_GET_OBJDEF 7 215 #define SNMP_MSG_EXTERNAL_GET_VALUE 8 216 #define SNMP_MSG_EXTERNAL_SET_TEST 9 217 #define SNMP_MSG_EXTERNAL_GET_OBJDEF_S 10 218 #define SNMP_MSG_EXTERNAL_SET_VALUE 11 219 220 #define SNMP_COMMUNITY_STR_LEN 64 221 struct snmp_msg_pstat 222 { 223 /* lwIP local port (161) binding */ 224 struct udp_pcb *pcb; 225 /* source IP address */ 226 ip_addr_t sip; 227 /* source UDP port */ 228 u16_t sp; 229 /* request type */ 230 u8_t rt; 231 /* request ID */ 232 s32_t rid; 233 /* error status */ 234 s32_t error_status; 235 /* error index */ 236 s32_t error_index; 237 /* community name (zero terminated) */ 238 u8_t community[SNMP_COMMUNITY_STR_LEN + 1]; 239 /* community string length (exclusive zero term) */ 240 u8_t com_strlen; 241 /* one out of MSG_EMPTY, MSG_DEMUX, MSG_INTERNAL, MSG_EXTERNAL_x */ 242 u8_t state; 243 /* saved arguments for MSG_EXTERNAL_x */ 244 struct mib_external_node *ext_mib_node; 245 struct snmp_name_ptr ext_name_ptr; 246 struct obj_def ext_object_def; 247 struct snmp_obj_id ext_oid; 248 /* index into input variable binding list */ 249 u8_t vb_idx; 250 /* ptr into input variable binding list */ 251 struct snmp_varbind *vb_ptr; 252 /* list of variable bindings from input */ 253 struct snmp_varbind_root invb; 254 /* list of variable bindings to output */ 255 struct snmp_varbind_root outvb; 256 /* output response lengths used in ASN encoding */ 257 struct snmp_resp_header_lengths rhl; 258 }; 259 260 struct snmp_msg_trap 261 { 262 /* lwIP local port (161) binding */ 263 struct udp_pcb *pcb; 264 /* destination IP address in network order */ 265 ip_addr_t dip; 266 267 /* source enterprise ID (sysObjectID) */ 268 struct snmp_obj_id *enterprise; 269 /* source IP address, raw network order format */ 270 u8_t sip_raw[4]; 271 /* generic trap code */ 272 u32_t gen_trap; 273 /* specific trap code */ 274 u32_t spc_trap; 275 /* timestamp */ 276 u32_t ts; 277 /* list of variable bindings to output */ 278 struct snmp_varbind_root outvb; 279 /* output trap lengths used in ASN encoding */ 280 struct snmp_trap_header_lengths thl; 281 }; 282 283 /** Agent Version constant, 0 = v1 oddity */ 284 extern const s32_t snmp_version; 285 /** Agent default "public" community string */ 286 extern const char snmp_publiccommunity[7]; 287 288 extern struct snmp_msg_trap trap_msg; 289 290 /** Agent setup, start listening to port 161. */ 291 void snmp_init(void); 292 void snmp_trap_dst_enable(u8_t dst_idx, u8_t enable); 293 void snmp_trap_dst_ip_set(u8_t dst_idx, ip_addr_t *dst); 294 295 /** Varbind-list functions. */ 296 struct snmp_varbind* snmp_varbind_alloc(struct snmp_obj_id *oid, u8_t type, u8_t len); 297 void snmp_varbind_free(struct snmp_varbind *vb); 298 void snmp_varbind_list_free(struct snmp_varbind_root *root); 299 void snmp_varbind_tail_add(struct snmp_varbind_root *root, struct snmp_varbind *vb); 300 struct snmp_varbind* snmp_varbind_tail_remove(struct snmp_varbind_root *root); 301 302 /** Handle an internal (recv) or external (private response) event. */ 303 void snmp_msg_event(u8_t request_id); 304 err_t snmp_send_response(struct snmp_msg_pstat *m_stat); 305 err_t snmp_send_trap(s8_t generic_trap, struct snmp_obj_id *eoid, s32_t specific_trap); 306 void snmp_coldstart_trap(void); 307 void snmp_authfail_trap(void); 308 309 #ifdef __cplusplus 310 } 311 #endif 312 313 #endif /* LWIP_SNMP */ 314 315 #endif /* __LWIP_SNMP_MSG_H__ */ 316
