config.c

加密解密,安全工具！很有意思的代码

/*******************************************************************
*
*      Copyright (c) 1994-1999 Jetico, Inc., Finland
*      All rights reserved.
*
*      File: bccreate.c
*      Revision: $Id: config.c,v 1.4 2002/10/29 07:11:31 crypt Rel-1.6-3 $
*      Created:
*      Description: implementation of config reading routine
*
*******************************************************************/




#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <malloc.h>
#include <ctype.h>
#include "config.h"

char config_c[]="$Id: config.c,v 1.4 2002/10/29 07:11:31 crypt Rel-1.6-3 $";

alg_info *first=NULL;

struct status
{
    char    *prefix;                /* bc device name prefix  */
    int     alg_num;                /* total algorithms       */
    int     lineno;                 /* last line read         */
} runtime;

int alloc_info_struct (alg_info **p)
{
    *p = (alg_info *)malloc(sizeof(alg_info));   
    if ( !*p ) return NO_MEM;
    if ( first==NULL )
    {
        first=*p;
        first->next=first;
    };
    (*p)->next=first->next;
    first->next=*p;
    (*p)->key_size=0;
    return NO_ERROR;
}



int read_token(FILE *file, char *buf, int buflen)
{
    int c, error, len = 1, got_it = 0;

    error = TOKEN_EMPTY;
    while ( 1 )
    {
        if ( (c = fgetc(file)) < 0 ) goto end;

        switch ( c )
        {
            case '\n':
                runtime.lineno++;
                if ( !got_it ) break;
            case EOF:
                error = TOKEN_OK;
                goto end;
            case '#':
            case ';':
                error = TOKEN_OK;
                while ( 1 )
                    if ( (c = fgetc(file)) < 0 ) goto end;
                    else if ( c == '\n' ) break;
                runtime.lineno++;
                if ( !got_it ) break;
                else goto end;
            case ' ':
            case '\t':
                error = TOKEN_OK;
                if ( !got_it ) break;
                else goto end;          
            case '\\':
                if ( (c = fgetc(file)) < 0 ) goto end;
            default:
                got_it = 1;
                *buf++ = tolower(c);
                if ( ++len >= buflen )
                {
                    error = TOKEN_TRUNC;
                    goto end;
                }
                else break;                   
        }       
    }
    end:
    *buf++ = 0;
    return error;
}

void init_runtime_status()
{
    runtime.prefix  = 0;
    runtime.alg_num = 0;
    runtime.lineno  = 1;
}

int add_string(FILE *file, char **where_to)
{
    char buf[1024];

    if ( !file )
        return FATAL_ERROR;
    if ( read_token(file, buf, sizeof(buf)) != 0 )
        return CONF_BAD_FILE;
    *where_to = (char *)malloc(strlen(buf)+1);  
    if ( !*where_to )
        return NO_MEM;
    strcpy(*where_to, buf);
    return 0;
}

int add_number(FILE *file, int *where_to)
{
    char *err;
    char buf[1024];

    if ( !file )
        return FATAL_ERROR;
    if ( read_token(file, buf, sizeof(buf)) != 0 )
        return CONF_BAD_FILE;
    *where_to = strtol(buf, &err, 0);
    if ( *err != '\0' )
        return TOKEN_BAD;
    else
        return 0; 
}

int read_conf()
{
    FILE    *file;
    int i, rc;
    char    buf[1024];
    alg_info *ptr;

//	if (!filename) return CONF_BAD_FNAME;
    file = fopen(CONFIG_FILE, "r");
    if ( !file ) return CONF_FOPEN_ERR;
    init_runtime_status();
    i = 0;
    while ( !feof(file) )
    {
        rc = read_token(file, buf, sizeof(buf));
        if ( TOKEN_EMPTY == rc )
            return NO_ERROR;
        if ( 0 > rc )
            return CONF_BAD_FILE;
        if ( !strcmp(buf, "module") )
        {
            if ( alloc_info_struct(&ptr) )
                return NO_MEM;
            if ( add_string(file, &ptr->mod_name) < 0 )
                return CONF_BAD_FILE;
            if ( add_number(file, &ptr->id) < 0 )
                return CONF_BAD_FILE;
            if ( add_number(file, &ptr->key_size) < 0 )
                return CONF_BAD_FILE;
            if ( add_string(file, &ptr->alg_name) < 0 )
                return CONF_BAD_FILE;
            i++;        
        }
        if ( !strcmp(buf, "prefix") )
        {
            if ( add_string(file, &runtime.prefix) < 0 )
                return CONF_BAD_FILE;
        }
        runtime.alg_num = i;
    }
    fclose(file);
    return NO_ERROR;
}

alg_info *GetInfoById(int id)
{
    alg_info *p;
    p=first;
    do
    {
        if ( p->id==id ) return p;
        p=p->next;
    }while ( p!=first );
    return NULL;
}

alg_info *GetInfoByName(char *name)
{
    alg_info *p;
    p=first;
    do
    {
        if ( !strcmp(p->alg_name, name) ) return p;
        p=p->next;
    }while ( p!=first );
    return NULL;
}

char *GetPrefix()
{
    return runtime.prefix;
}