lwip_snmp_msg.h

00001 /**
00002  * @file
00003  * SNMP Agent message handling structures (internal API, do not use in client code).
00004  */
00005 
00006 /*
00007  * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
00008  * Copyright (c) 2016 Elias Oenal.
00009  * All rights reserved.
00010  *
00011  * Redistribution and use in source and binary forms, with or without modification,
00012  * are permitted provided that the following conditions are met:
00013  *
00014  * 1. Redistributions of source code must retain the above copyright notice,
00015  *    this list of conditions and the following disclaimer.
00016  * 2. Redistributions in binary form must reproduce the above copyright notice,
00017  *    this list of conditions and the following disclaimer in the documentation
00018  *    and/or other materials provided with the distribution.
00019  * 3. The name of the author may not be used to endorse or promote products
00020  *    derived from this software without specific prior written permission.
00021  *
00022  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
00023  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
00024  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
00025  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
00026  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
00027  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
00028  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
00029  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
00030  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
00031  * OF SUCH DAMAGE.
00032  *
00033  * Author: Christiaan Simons <christiaan.simons@axon.tv>
00034  *         Martin Hentschel <info@cl-soft.de>
00035  *         Elias Oenal <lwip@eliasoenal.com>
00036  */
00037 
00038 #ifndef LWIP_HDR_APPS_SNMP_MSG_H
00039 #define LWIP_HDR_APPS_SNMP_MSG_H
00040 
00041 #include "lwip/apps/snmp_opts.h"
00042 
00043 #if LWIP_SNMP
00044 
00045 #include "lwip/apps/snmp.h"
00046 #include "lwip/apps/snmp_core.h"
00047 #include "snmp_pbuf_stream.h"
00048 #include "lwip/ip_addr.h"
00049 #include "lwip/err.h"
00050 
00051 #if LWIP_SNMP_V3
00052 #include "snmpv3_priv.h"
00053 #endif
00054 
00055 
00056 #ifdef __cplusplus
00057 extern "C" {
00058 #endif
00059 
00060 /* version defines used in PDU */
00061 #define SNMP_VERSION_1  0
00062 #define SNMP_VERSION_2c 1
00063 #define SNMP_VERSION_3  3
00064 
00065 struct snmp_varbind_enumerator {
00066   struct snmp_pbuf_stream pbuf_stream;
00067   u16_t varbind_count;
00068 };
00069 
00070 typedef enum {
00071   SNMP_VB_ENUMERATOR_ERR_OK            = 0,
00072   SNMP_VB_ENUMERATOR_ERR_EOVB          = 1,
00073   SNMP_VB_ENUMERATOR_ERR_ASN1ERROR     = 2,
00074   SNMP_VB_ENUMERATOR_ERR_INVALIDLENGTH = 3
00075 } snmp_vb_enumerator_err_t;
00076 
00077 void snmp_vb_enumerator_init(struct snmp_varbind_enumerator *enumerator, struct pbuf *p, u16_t offset, u16_t length);
00078 snmp_vb_enumerator_err_t snmp_vb_enumerator_get_next(struct snmp_varbind_enumerator *enumerator, struct snmp_varbind *varbind);
00079 
00080 struct snmp_request {
00081   /* Communication handle */
00082   void *handle;
00083   /* source IP address */
00084   const ip_addr_t *source_ip;
00085   /* source UDP port */
00086   u16_t source_port;
00087   /* incoming snmp version */
00088   u8_t version;
00089   /* community name (zero terminated) */
00090   u8_t community[SNMP_MAX_COMMUNITY_STR_LEN + 1];
00091   /* community string length (exclusive zero term) */
00092   u16_t community_strlen;
00093   /* request type */
00094   u8_t request_type;
00095   /* request ID */
00096   s32_t request_id;
00097   /* error status */
00098   s32_t error_status;
00099   /* error index */
00100   s32_t error_index;
00101   /* non-repeaters (getBulkRequest (SNMPv2c)) */
00102   s32_t non_repeaters;
00103   /* max-repetitions (getBulkRequest (SNMPv2c)) */
00104   s32_t max_repetitions;
00105 
00106   /* Usually response-pdu (2). When snmpv3 errors are detected report-pdu(8) */
00107   u8_t request_out_type;
00108 
00109 #if LWIP_SNMP_V3
00110   s32_t msg_id;
00111   s32_t msg_max_size;
00112   u8_t  msg_flags;
00113   s32_t msg_security_model;
00114   u8_t  msg_authoritative_engine_id[SNMP_V3_MAX_ENGINE_ID_LENGTH];
00115   u8_t  msg_authoritative_engine_id_len;
00116   s32_t msg_authoritative_engine_boots;
00117   s32_t msg_authoritative_engine_time;
00118   u8_t  msg_user_name[SNMP_V3_MAX_USER_LENGTH];
00119   u8_t  msg_user_name_len;
00120   u8_t  msg_authentication_parameters[SNMP_V3_MAX_AUTH_PARAM_LENGTH];
00121   u8_t  msg_authentication_parameters_len;
00122   u8_t  msg_privacy_parameters[SNMP_V3_MAX_PRIV_PARAM_LENGTH];
00123   u8_t  msg_privacy_parameters_len;
00124   u8_t  context_engine_id[SNMP_V3_MAX_ENGINE_ID_LENGTH];
00125   u8_t  context_engine_id_len;
00126   u8_t  context_name[SNMP_V3_MAX_ENGINE_ID_LENGTH];
00127   u8_t  context_name_len;
00128 #endif
00129 
00130   struct pbuf *inbound_pbuf;
00131   struct snmp_varbind_enumerator inbound_varbind_enumerator;
00132   u16_t inbound_varbind_offset;
00133   u16_t inbound_varbind_len;
00134   u16_t inbound_padding_len;
00135 
00136   struct pbuf *outbound_pbuf;
00137   struct snmp_pbuf_stream outbound_pbuf_stream;
00138   u16_t outbound_pdu_offset;
00139   u16_t outbound_error_status_offset;
00140   u16_t outbound_error_index_offset;
00141   u16_t outbound_varbind_offset;
00142 #if LWIP_SNMP_V3
00143   u16_t outbound_msg_global_data_offset;
00144   u16_t outbound_msg_global_data_end;
00145   u16_t outbound_msg_security_parameters_str_offset;
00146   u16_t outbound_msg_security_parameters_seq_offset;
00147   u16_t outbound_msg_security_parameters_end;
00148   u16_t outbound_msg_authentication_parameters_offset;
00149   u16_t outbound_scoped_pdu_seq_offset;
00150   u16_t outbound_scoped_pdu_string_offset;
00151 #endif
00152 
00153   u8_t value_buffer[SNMP_MAX_VALUE_SIZE];
00154 };
00155 
00156 /** A helper struct keeping length information about varbinds */
00157 struct snmp_varbind_len {
00158   u8_t  vb_len_len;
00159   u16_t vb_value_len;
00160   u8_t  oid_len_len;
00161   u16_t oid_value_len;
00162   u8_t  value_len_len;
00163   u16_t value_value_len;
00164 };
00165 
00166 /** Agent community string */
00167 extern const char *snmp_community;
00168 /** Agent community string for write access */
00169 extern const char *snmp_community_write;
00170 /** handle for sending traps */
00171 extern void *snmp_traps_handle;
00172 
00173 void snmp_receive(void *handle, struct pbuf *p, const ip_addr_t *source_ip, u16_t port);
00174 err_t snmp_sendto(void *handle, struct pbuf *p, const ip_addr_t *dst, u16_t port);
00175 u8_t snmp_get_local_ip_for_dst(void *handle, const ip_addr_t *dst, ip_addr_t *result);
00176 err_t snmp_varbind_length(struct snmp_varbind *varbind, struct snmp_varbind_len *len);
00177 err_t snmp_append_outbound_varbind(struct snmp_pbuf_stream *pbuf_stream, struct snmp_varbind *varbind);
00178 
00179 #ifdef __cplusplus
00180 }
00181 #endif
00182 
00183 #endif /* LWIP_SNMP */
00184 
00185 #endif /* LWIP_HDR_APPS_SNMP_MSG_H */