lib/drivers/lwip/src/include/lwip/snmp_msg.h

   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@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
  42 #if LWIP_SNMP
  43
  44 #if SNMP_PRIVATE_MIB
  45 #include "private_mib.h"
  46 #endif
  47
  48 #ifdef __cplusplus
  49 extern "C" {
  50 #endif
  51
  52 /* The listen port of the SNMP agent. Clients have to make their requests to
  53    this port. Most standard clients won't work if you change this! */
  54 #ifndef SNMP_IN_PORT
  55 #define SNMP_IN_PORT 161
  56 #endif
  57 /* The remote port the SNMP agent sends traps to. Most standard trap sinks won't
  58    work if you change this! */
  59 #ifndef SNMP_TRAP_PORT
  60 #define SNMP_TRAP_PORT 162
  61 #endif
  62
  63 #define SNMP_ES_NOERROR 0
  64 #define SNMP_ES_TOOBIG 1
  65 #define SNMP_ES_NOSUCHNAME 2
  66 #define SNMP_ES_BADVALUE 3
  67 #define SNMP_ES_READONLY 4
  68 #define SNMP_ES_GENERROR 5
  69
  70 #define SNMP_GENTRAP_COLDSTART 0
  71 #define SNMP_GENTRAP_WARMSTART 1
  72 #define SNMP_GENTRAP_AUTHFAIL 4
  73 #define SNMP_GENTRAP_ENTERPRISESPC 6
  74
  75 struct snmp_varbind
  76 {
  77   /* next pointer, NULL for last in list */
  78   struct snmp_varbind *next;
  79   /* previous pointer, NULL for first in list */
  80   struct snmp_varbind *prev;
  81
  82   /* object identifier length (in s32_t) */
  83   u8_t ident_len;
  84   /* object identifier array */
  85   s32_t *ident;
  86
  87   /* object value ASN1 type */
  88   u8_t value_type;
  89   /* object value length (in u8_t) */
  90   u8_t value_len;
  91   /* object value */
  92   void *value;
  93
  94   /* encoding varbind seq length length */
  95   u8_t seqlenlen;
  96   /* encoding object identifier length length */
  97   u8_t olenlen;
  98   /* encoding object value length length */
  99   u8_t vlenlen;
 100   /* encoding varbind seq length */
 101   u16_t seqlen;
 102   /* encoding object identifier length */
 103   u16_t olen;
 104   /* encoding object value length */
 105   u16_t vlen;
 106 };
 107
 108 struct snmp_varbind_root
 109 {
 110   struct snmp_varbind *head;
 111   struct snmp_varbind *tail;
 112   /* number of variable bindings in list */
 113   u8_t count;
 114   /* encoding varbind-list seq length length */
 115   u8_t seqlenlen;
 116   /* encoding varbind-list seq length */
 117   u16_t seqlen;
 118 };
 119
 120 /** output response message header length fields */
 121 struct snmp_resp_header_lengths
 122 {
 123   /* encoding error-index length length */
 124   u8_t erridxlenlen;
 125   /* encoding error-status length length */
 126   u8_t errstatlenlen;
 127   /* encoding request id length length */
 128   u8_t ridlenlen;
 129   /* encoding pdu length length */
 130   u8_t pdulenlen;
 131   /* encoding community length length */
 132   u8_t comlenlen;
 133   /* encoding version length length */
 134   u8_t verlenlen;
 135   /* encoding sequence length length */
 136   u8_t seqlenlen;
 137
 138   /* encoding error-index length */
 139   u16_t erridxlen;
 140   /* encoding error-status length */
 141   u16_t errstatlen;
 142   /* encoding request id length */
 143   u16_t ridlen;
 144   /* encoding pdu length */
 145   u16_t pdulen;
 146   /* encoding community length */
 147   u16_t comlen;
 148   /* encoding version length */
 149   u16_t verlen;
 150   /* encoding sequence length */
 151   u16_t seqlen;
 152 };
 153
 154 /** output response message header length fields */
 155 struct snmp_trap_header_lengths
 156 {
 157   /* encoding timestamp length length */
 158   u8_t tslenlen;
 159   /* encoding specific-trap length length */
 160   u8_t strplenlen;
 161   /* encoding generic-trap length length */
 162   u8_t gtrplenlen;
 163   /* encoding agent-addr length length */
 164   u8_t aaddrlenlen;
 165   /* encoding enterprise-id length length */
 166   u8_t eidlenlen;
 167   /* encoding pdu length length */
 168   u8_t pdulenlen;
 169   /* encoding community length length */
 170   u8_t comlenlen;
 171   /* encoding version length length */
 172   u8_t verlenlen;
 173   /* encoding sequence length length */
 174   u8_t seqlenlen;
 175
 176   /* encoding timestamp length */
 177   u16_t tslen;
 178   /* encoding specific-trap length */
 179   u16_t strplen;
 180   /* encoding generic-trap length */
 181   u16_t gtrplen;
 182   /* encoding agent-addr length */
 183   u16_t aaddrlen;
 184   /* encoding enterprise-id length */
 185   u16_t eidlen;
 186   /* encoding pdu length */
 187   u16_t pdulen;
 188   /* encoding community length */
 189   u16_t comlen;
 190   /* encoding version length */
 191   u16_t verlen;
 192   /* encoding sequence length */
 193   u16_t seqlen;
 194 };
 195
 196 /* Accepting new SNMP messages. */
 197 #define SNMP_MSG_EMPTY                 0
 198 /* Search for matching object for variable binding. */
 199 #define SNMP_MSG_SEARCH_OBJ            1
 200 /* Perform SNMP operation on in-memory object.
 201    Pass-through states, for symmetry only. */
 202 #define SNMP_MSG_INTERNAL_GET_OBJDEF   2
 203 #define SNMP_MSG_INTERNAL_GET_VALUE    3
 204 #define SNMP_MSG_INTERNAL_SET_TEST     4
 205 #define SNMP_MSG_INTERNAL_GET_OBJDEF_S 5
 206 #define SNMP_MSG_INTERNAL_SET_VALUE    6
 207 /* Perform SNMP operation on object located externally.
 208    In theory this could be used for building a proxy agent.
 209    Practical use is for an enterprise spc. app. gateway. */
 210 #define SNMP_MSG_EXTERNAL_GET_OBJDEF   7
 211 #define SNMP_MSG_EXTERNAL_GET_VALUE    8
 212 #define SNMP_MSG_EXTERNAL_SET_TEST     9
 213 #define SNMP_MSG_EXTERNAL_GET_OBJDEF_S 10
 214 #define SNMP_MSG_EXTERNAL_SET_VALUE    11
 215
 216 #define SNMP_COMMUNITY_STR_LEN 64
 217 struct snmp_msg_pstat
 218 {
 219   /* lwIP local port (161) binding */
 220   struct udp_pcb *pcb;
 221   /* source IP address */
 222   struct ip_addr sip;
 223   /* source UDP port */
 224   u16_t sp;
 225   /* request type */
 226   u8_t rt;
 227   /* request ID */
 228   s32_t rid;
 229   /* error status */
 230   s32_t error_status;
 231   /* error index */
 232   s32_t error_index;
 233   /* community name (zero terminated) */
 234   u8_t community[SNMP_COMMUNITY_STR_LEN + 1];
 235   /* community string length (exclusive zero term) */
 236   u8_t com_strlen;
 237   /* one out of MSG_EMPTY, MSG_DEMUX, MSG_INTERNAL, MSG_EXTERNAL_x */
 238   u8_t state;
 239   /* saved arguments for MSG_EXTERNAL_x */
 240   struct mib_external_node *ext_mib_node;
 241   struct snmp_name_ptr ext_name_ptr;
 242   struct obj_def ext_object_def;
 243   struct snmp_obj_id ext_oid;
 244   /* index into input variable binding list */
 245   u8_t vb_idx;
 246   /* ptr into input variable binding list */
 247   struct snmp_varbind *vb_ptr;
 248   /* list of variable bindings from input */
 249   struct snmp_varbind_root invb;
 250   /* list of variable bindings to output */
 251   struct snmp_varbind_root outvb;
 252   /* output response lengths used in ASN encoding */
 253   struct snmp_resp_header_lengths rhl;
 254 };
 255
 256 struct snmp_msg_trap
 257 {
 258   /* lwIP local port (161) binding */
 259   struct udp_pcb *pcb;
 260   /* destination IP address in network order */
 261   struct ip_addr dip;
 262
 263   /* source enterprise ID (sysObjectID) */
 264   struct snmp_obj_id *enterprise;
 265   /* source IP address, raw network order format */
 266   u8_t sip_raw[4];
 267   /* generic trap code */
 268   u32_t gen_trap;
 269   /* specific trap code */
 270   u32_t spc_trap;
 271   /* timestamp */
 272   u32_t ts;
 273   /* list of variable bindings to output */
 274   struct snmp_varbind_root outvb;
 275   /* output trap lengths used in ASN encoding */
 276   struct snmp_trap_header_lengths thl;
 277 };
 278
 279 /** Agent Version constant, 0 = v1 oddity */
 280 extern const s32_t snmp_version;
 281 /** Agent default "public" community string */
 282 extern const char snmp_publiccommunity[7];
 283
 284 extern struct snmp_msg_trap trap_msg;
 285
 286 /** Agent setup, start listening to port 161. */
 287 void snmp_init(void);
 288 void snmp_trap_dst_enable(u8_t dst_idx, u8_t enable);
 289 void snmp_trap_dst_ip_set(u8_t dst_idx, struct ip_addr *dst);
 290
 291 /** Varbind-list functions. */
 292 struct snmp_varbind* snmp_varbind_alloc(struct snmp_obj_id *oid, u8_t type, u8_t len);
 293 void snmp_varbind_free(struct snmp_varbind *vb);
 294 void snmp_varbind_list_free(struct snmp_varbind_root *root);
 295 void snmp_varbind_tail_add(struct snmp_varbind_root *root, struct snmp_varbind *vb);
 296 struct snmp_varbind* snmp_varbind_tail_remove(struct snmp_varbind_root *root);
 297
 298 /** Handle an internal (recv) or external (private response) event. */
 299 void snmp_msg_event(u8_t request_id);
 300 err_t snmp_send_response(struct snmp_msg_pstat *m_stat);
 301 err_t snmp_send_trap(s8_t generic_trap, struct snmp_obj_id *eoid, s32_t specific_trap);
 302 void snmp_coldstart_trap(void);
 303 void snmp_authfail_trap(void);
 304
 305 #ifdef __cplusplus
 306 }
 307 #endif
 308
 309 #endif /* LWIP_SNMP */
 310
 311 #endif /* __LWIP_SNMP_MSG_H__ */