dns.cpp

一个简易dns 服务器

#include "stdafx.h"
#include "dns.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <conio.h>
#include <time.h>
#include <windows.h>
#include <process.h>
 
  
struct MMyFileHeader *loadArray(char *inFileName, char **file_in, int *count)
{
    FILE *inFile;
	unsigned long temp=0;
 struct MMyFileHeader *header;
header=(struct MMyFileHeader *)malloc(sizeof(struct MMyFileHeader));
 memset(header,0,sizeof(struct MMyFileHeader));
 
    if ((inFile = fopen(inFileName, "rb")) == NULL)
    {
    fprintf(stderr,"Error opening input file, %s\n", inFileName);
    return NULL;
    }
 	fread(&header->Size,1,4,inFile);
 	fread(&header->Index,1,4*26,inFile);
 fread(&header->count,1,4,inFile);
    (*file_in)=(char *)malloc(header->Size-28*4); 
	 if ((*file_in) == NULL)
    {
    fprintf(stderr, "Malloc of array in loadArray failed!\n");
    return NULL;
    }
	memset(*file_in,0,header->Size-28*4);
     fread((*file_in),1,header->Size-28*4,inFile);
		fclose(inFile);

printf("Reading file %s (each . is 1000 words read)\n", inFileName);
    *count = header->count;
    return header;
}
int isString(char *file_in,char *word)
{
	char *ptemp=NULL;
	ptemp=file_in;
 
	while((*ptemp)!='\n')
	 ptemp++;
	 memcpy(word,file_in,ptemp-file_in);
	return 1;
};
  
int LoadDate(char *inFileName, char **file_in, int *count)
{
 FILE *inFile;
int Size;
    if ((inFile = fopen(inFileName, "rb")) == NULL)
    {
    fprintf(stderr,"Error opening input file, %s\n", inFileName);
    return 0;
    }
fread(&Size,1,4,inFile);
fseek(inFile,27*4,SEEK_SET); 
fread(count,1,4,inFile);
 (*file_in)=(char *)malloc(Size-28*4);
 memset(*file_in,0,Size-28*4);
fread((*file_in),1,Size-28*4,inFile);
fclose(inFile);
return 1;
}

unsigned _stdcall ip_d(LPVOID myarg) //ip查DOMAIN
{
    
char *word;
char filename[WORD_LENGTH];
int No;
    int j=0;
     int k=0;
	 char *array;
	 int count;
    char out[WORD_LENGTH];

    char *gc;
	char *p;
	char *Domin;

word=((struct MyArg *)myarg)->find;
	No=((struct MyArg *)myarg)->k;

	switch(No)
	{
		case 0:strcpy(filename,"G:\\\\com") ;break;
		case 1:strcpy(filename,"G:\\\\cn") ;break;
		case 2:strcpy(filename,"G:\\\\net") ;break;
		case 3:strcpy(filename,"G:\\\\hk") ;break;
		case 4:strcpy(filename,"G:\\\\org") ;break;
	}
	if (!LoadDate(filename,&array,&count))
    {
        fprintf(stderr,"    loadArray failed! Program terminating...\n");
        return EXIT_FAILURE; 
    }
	 
   	if((gc=strstr(array,word)))
   
         {            
         		  memset(out,0,WORD_LENGTH);
				 
				 for(Domin=gc;(*Domin)!='\n';Domin--);
				   memcpy(out,Domin+1,gc-Domin-2);
					p=filename;
					while(*(p++)=='\\');
					strcat(out,".");
					strcat(out,p+3);
					if(No!=0)
						strcat((*((struct MyArg *)myarg)->dns_result),";");
				   strcat((*((struct MyArg *)myarg)->dns_result),out);
                                                         
         }
  
	else    printf("%s ignored(not found) in %s !\n",word,filename);
		  free(array); 

} 

char *Word_Postfix(char *in,char *open)
{
char *p;
char *org=in;
char ptem[WORD_LENGTH]="";
while(*(in++)!='.');
p=in;
while(*(++p)!=0);
memcpy(ptem,in,p-in);
 
sprintf(open,"G:\\\\%s",ptem);
 
*(--in)=0;
strcpy(ptem,org);
memset(org,0,WORD_LENGTH);
strcpy(org,ptem);
 
 return ptem;
}

void d_ip(char **wordArray, int *count,char *word1,char **dns_result) //DOMAIN查ip
{
    char word[WORD_LENGTH];	
	
    char IP[WORD_LENGTH];
	char Postfix[WORD_LENGTH];
	char openfile[WORD_LENGTH];
	char *p;
	char *p2;
	int found=0;
	struct MMyFileHeader *header;
	memset(word,0,WORD_LENGTH);
	memset(IP,0,WORD_LENGTH);
	memset(Postfix,0,WORD_LENGTH);
	memset(openfile,0,WORD_LENGTH);

	 
    printf("Domain Name = %s,",word1);

	strcpy(word,word1);
Word_Postfix(word,openfile);
 
if (!(header=loadArray(openfile,wordArray,count)))
    {
        fprintf(stderr,"    loadArray failed! Program terminating...\n");
     
    }

	p2=*wordArray+header->Index[word[0]-'a']-28*4;
	while(p=strstr(p2,word))
	{
		
		

			p2=p;
			if(*(p-1)!='\n'){
				   while((*p2++)!='\n');
				  continue;
			  }
              p+=strlen(word);  
			  if((*p)!='_'){
				   while((*p2++)!='\n');
				  continue;
			  }
			  p++;
				memset(IP,0,WORD_LENGTH);

 
				 
			 if(isString(p,IP))
			 {
			 	fflush(stdout); 
				  fprintf(stderr,"%s IP Address is %s \n",word1,IP);
                found=1;
                                                               
			 }
			 
			  
			 while((*p2++)!='\n');

	}
	if(!found)
		{
          printf("%s ignored(not found)!\n",word1);
		  sprintf(IP,"(not found)!\n");
			//return;
		}
        free(header);
		memcpy(*dns_result,IP,sizeof(IP));
		
}