snmp_asn1.h

00001 /**
00002  * @file
00003  * Abstract Syntax Notation One (ISO 8824, 8825) codec.
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_ASN1_H
00039 #define LWIP_HDR_APPS_SNMP_ASN1_H
00040 
00041 #include "lwip/apps/snmp_opts.h"
00042 
00043 #if LWIP_SNMP
00044 
00045 #include "lwip/err.h"
00046 #include "lwip/apps/snmp_core.h"
00047 #include "snmp_pbuf_stream.h"
00048 
00049 #ifdef __cplusplus
00050 extern "C" {
00051 #endif
00052 
00053 #define SNMP_ASN1_TLV_INDEFINITE_LENGTH 0x80
00054 
00055 #define SNMP_ASN1_CLASS_MASK        0xC0
00056 #define SNMP_ASN1_CONTENTTYPE_MASK  0x20
00057 #define SNMP_ASN1_DATATYPE_MASK     0x1F
00058 #define SNMP_ASN1_DATATYPE_EXTENDED 0x1F /* DataType indicating that datatype is encoded in following bytes */
00059 
00060 /* context specific (SNMP) tags (from SNMP spec. RFC1157) */
00061 #define SNMP_ASN1_CONTEXT_PDU_GET_REQ      0
00062 #define SNMP_ASN1_CONTEXT_PDU_GET_NEXT_REQ 1
00063 #define SNMP_ASN1_CONTEXT_PDU_GET_RESP     2
00064 #define SNMP_ASN1_CONTEXT_PDU_SET_REQ      3
00065 #define SNMP_ASN1_CONTEXT_PDU_TRAP         4
00066 #define SNMP_ASN1_CONTEXT_PDU_GET_BULK_REQ 5
00067 
00068 #define SNMP_ASN1_CONTEXT_VARBIND_NO_SUCH_OBJECT      0
00069 #define SNMP_ASN1_CONTEXT_VARBIND_END_OF_MIB_VIEW     2
00070 
00071 struct snmp_asn1_tlv
00072 {
00073   u8_t  type;       /* only U8 because extended types are not specified by SNMP */
00074   u8_t  type_len;   /* encoded length of 'type' field (normally 1) */
00075   u8_t  length_len; /* indicates how many bytes are required to encode the 'value_len' field */
00076   u16_t value_len;  /* encoded length of the value */
00077 };
00078 #define SNMP_ASN1_TLV_HDR_LENGTH(tlv) ((tlv).type_len + (tlv).length_len)
00079 #define SNMP_ASN1_TLV_LENGTH(tlv) ((tlv).type_len + (tlv).length_len + (tlv).value_len)
00080 #define SNMP_ASN1_SET_TLV_PARAMS(tlv, type_, length_len_, value_len_) do { (tlv).type = (type_); (tlv).type_len = 0; (tlv).length_len = (length_len_); (tlv).value_len = (value_len_); } while (0);
00081 
00082 err_t snmp_asn1_dec_tlv(struct snmp_pbuf_stream* pbuf_stream, struct snmp_asn1_tlv* tlv);
00083 err_t snmp_asn1_dec_u32t(struct snmp_pbuf_stream *pbuf_stream, u16_t len, u32_t *value);
00084 err_t snmp_asn1_dec_u64t(struct snmp_pbuf_stream *pbuf_stream, u16_t len, u32_t *value);
00085 err_t snmp_asn1_dec_s32t(struct snmp_pbuf_stream *pbuf_stream, u16_t len, s32_t *value);
00086 err_t snmp_asn1_dec_oid(struct snmp_pbuf_stream *pbuf_stream, u16_t len, u32_t* oid, u8_t* oid_len, u8_t oid_max_len);
00087 err_t snmp_asn1_dec_raw(struct snmp_pbuf_stream *pbuf_stream, u16_t len, u8_t *buf, u16_t* buf_len, u16_t buf_max_len);
00088 
00089 err_t snmp_ans1_enc_tlv(struct snmp_pbuf_stream* pbuf_stream, struct snmp_asn1_tlv* tlv);
00090 
00091 void snmp_asn1_enc_length_cnt(u16_t length, u8_t *octets_needed);
00092 void snmp_asn1_enc_u32t_cnt(u32_t value, u16_t *octets_needed);
00093 void snmp_asn1_enc_u64t_cnt(const u32_t *value, u16_t *octets_needed);
00094 void snmp_asn1_enc_s32t_cnt(s32_t value, u16_t *octets_needed);
00095 void snmp_asn1_enc_oid_cnt(const u32_t *oid, u16_t oid_len, u16_t *octets_needed);
00096 err_t snmp_asn1_enc_oid(struct snmp_pbuf_stream* pbuf_stream, const u32_t *oid, u16_t oid_len);
00097 err_t snmp_asn1_enc_s32t(struct snmp_pbuf_stream* pbuf_stream, u16_t octets_needed, s32_t value);
00098 err_t snmp_asn1_enc_u32t(struct snmp_pbuf_stream* pbuf_stream, u16_t octets_needed, u32_t value);
00099 err_t snmp_asn1_enc_u64t(struct snmp_pbuf_stream* pbuf_stream, u16_t octets_needed, const u32_t* value);
00100 err_t snmp_asn1_enc_raw(struct snmp_pbuf_stream* pbuf_stream, const u8_t *raw, u16_t raw_len);
00101 
00102 #ifdef __cplusplus
00103 }
00104 #endif
00105 
00106 #endif /* LWIP_SNMP */
00107 
00108 #endif /* LWIP_HDR_APPS_SNMP_ASN1_H */