asn1.h

著名的入侵检测系统snort的最新版本的源码

/****************************************************************************
 *
 * Copyright (C) 2004-2007 Sourcefire, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License Version 2 as
 * published by the Free Software Foundation.  You may not use, modify or
 * distribute this program under any other version of the GNU General
 * Public License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 ****************************************************************************/
 
#ifndef __ASN1_H__
#define __ASN1_H__

/*
**  ASN.1 Identifier Classes
*/
#define SF_ASN1_CLASS_MASK        0xc0
#define SF_ASN1_CLASS_UNIVERSAL   0x00
#define SF_ASN1_CLASS_APPLICATION 0x40
#define SF_ASN1_CLASS_CONTEXT     0x80
#define SF_ASN1_CLASS_PRIVATE     0xc0

/*
**  ASN.1 Identifier Flags
*/
#define SF_ASN1_FLAG_MASK       0x20
#define SF_ASN1_FLAG_PRIMITIVE  0x00
#define SF_ASN1_FLAG_CONSTRUCT  0x20

/*
**  ASN.1 Universal Tags
*/
#define SF_ASN1_TAG_MASK      0x1f

#define SF_ASN1_TAG_RSV_ENC   0
#define SF_ASN1_TAG_BOOL      1 
#define SF_ASN1_TAG_INT       2
#define SF_ASN1_TAG_BIT_STR   3
#define SF_ASN1_TAG_OCT_STR   4
#define SF_ASN1_TAG_NULL      5
#define SF_ASN1_TAG_OBJ_IDENT 6
#define SF_ASN1_TAG_OBJ_DESC  7
#define SF_ASN1_TAG_EXT       8
#define SF_ASN1_TAG_REAL      9
#define SF_ASN1_TAG_ENUM      10
#define SF_ASN1_TAG_EMB_PDV   11
#define SF_ASN1_TAG_REL_OBJ   13

#define SF_ASN1_TAG_SEQ       16
#define SF_ASN1_TAG_SET       17 

#define SF_ASN1_TAG_UTF8_STR  12
#define SF_ASN1_TAG_NUM_STR   18
#define SF_ASN1_TAG_PRINT_STR 19 
#define SF_ASN1_TAG_T61_STR   20
#define SF_ASN1_TAG_VID_STR   21
#define SF_ASN1_TAG_IA5_STR   22
#define SF_ASN1_TAG_GRAPH_STR 25
#define SF_ASN1_TAG_VIS_STR   26
#define SF_ASN1_TAG_GEN_STR   27
#define SF_ASN1_TAG_UNIV_STR  28
#define SF_ASN1_TAG_BMP_STR   30

#define SF_ASN1_TAG_UTC_TIME  23
#define SF_ASN1_TAG_GEN_TIME  24

#define SF_ASN1_TAG_EXTENSION 31

/*
**  BER Length Decoding
*/
#define SF_BER_LEN_MASK      0x80
#define SF_BER_LEN_DEF_SHORT 1
#define SF_BER_LEN_DEF_LONG  2
#define SF_BER_LEN_INDEF     3

typedef struct s_ASN1_LEN
{
    unsigned char type;
    unsigned int  size;

} ASN1_LEN;

typedef struct s_ASN1_IDENT
{
    unsigned char  asn1_class;
    unsigned char  flag;
    unsigned char  tag_type;
    unsigned int   tag;

} ASN1_IDENT;

typedef struct s_ASN1_TYPE
{
    ASN1_IDENT ident;
    ASN1_LEN   len;
    
    const unsigned char     *data;
    unsigned int      data_len;

    unsigned char     eoc;

    struct s_ASN1_TYPE  *next;
    struct s_ASN1_TYPE  *cnext;
    
} ASN1_TYPE;

typedef struct s_ASN1_DATA
{
    const unsigned char *data;
    const unsigned char *start;
    const unsigned char *end;
    unsigned int   len;

} ASN1_DATA;

/*
**  Error Codes
*/
#define ASN1_ERR_OOB          1
#define ASN1_ERR_NONFATAL     2
#define ASN1_ERR_OVERLONG_LEN 3

#define ASN1_OK      0

#define ASN1_ERR_NULL_MEM            -1
#define ASN1_ERR_INVALID_BER_TAG_LEN -3
#define ASN1_ERR_MEM_ALLOC           -4
#define ASN1_ERR_FATAL               -5
#define ASN1_ERR_INVALID_INDEF_LEN   -6
#define ASN1_ERR_INVALID_ARG         -7
#define ASN1_ERR_STACK               -8

int asn1_init_mem(int iNodes);
void asn1_free_mem();
int asn1_decode(const unsigned char *data, unsigned int len, ASN1_TYPE **asn1_type);
int asn1_print_types(ASN1_TYPE *asn1_type, void *user);
int asn1_traverse(ASN1_TYPE *asn1, void * user, 
                  int (*DetectFunc)(ASN1_TYPE *, void *));

#endif