我已经实现了一个c程序，其中以混杂模式从网络接收原始数据包并将其存储在文本文件中。但我本来应该把它保存在二进制文件中。我怎样才能做到这一点？我的意思是我需要更改以将其另存为二进制文件。请任何人指导我吗？或者给我一个链接，我可以通过二进制文件处理程序并检查解决方案：（
这是我的data_capture_module：
int main()
{
int saddr_size , data_size;
struct sockaddr saddr;
gopromiscous();
unsigned char *buffer = (unsigned char *) malloc(1024);
logfile=fopen("sniff_data.txt","w");
if(logfile==NULL)
{
printf("Unable to create sniff_data file.");
}
printf("\n Starting..\n");
int sock_raw = socket( AF_PACKET , SOCK_RAW , htons(ETH_P_ALL)) ;
setsockopt(sock_raw , SOL_SOCKET , SO_BINDTODEVICE , "eth0" , strlen("eth0")+ 1 );
if(sock_raw < 0)
{
//Print the error with proper message
perror("Socket Error");
return 1;
}
int count=30;
while(count>=0)
{
count--;
saddr_size = sizeof saddr;
data_size = recvfrom(sock_raw , buffer , 1024, 0 , &saddr ,(socklen_t*)&saddr_size);
if(data_size <0 )
{
printf("Recvfrom error , failed to get packets\n");
return 1;
}
ProcessPacket(buffer , data_size);
}
fclose(logfile);
close(sock_raw);
printf("\n");
printf(" Finished\n\n");
return 0;
}
void ProcessPacket(unsigned char* buffer, int size)
{
//Get the IP Header part of this packet , excluding the ethernet header
struct iphdr *iph = (struct iphdr*)(buffer + sizeof(struct ethhdr));
++total;
switch (iph->protocol) //Check the Protocol and do accordingly...
{
case 1: //ICMP Protocol
++icmp;
print_icmp_packet( buffer , size);
break;
case 2: //IGMP Protocol
++igmp;
break;
case 6: //TCP Protocol
++tcp;
print_tcp_packet(buffer , size);
break;
case 17: //UDP Protocol
++udp;
print_udp_packet(buffer , size);
break;
default: //Some Other Protocol like ARP etc.
++others;
break;
}
printf(" TCP : %d UDP : %d ICMP : %d IGMP : %d Others : %d Total : %d\r",tcp, , udp , icmp , igmp , others , total);
}
void print_ethernet_header(unsigned char* Buffer, int Size)
{
struct ethhdr *eth = (struct ethhdr *)Buffer;
fprintf(logfile , "\n");
fprintf(logfile , "Ethernet Header\n");
fprintf(logfile , " |-Destination Address : %.2X-%.2X-%.2X-%.2X-%.2X-%.2X \n",
eth->h_dest[0] , eth->h_dest[1] , eth->h_dest[2] , eth->h_dest[3] , eth->h_dest[4] , eth->h_dest[5] );
fprintf(logfile , " |-Source Address : %.2X-%.2X-%.2X-%.2X-%.2X-%.2X \n",
eth->h_source[0] , eth->h_source[1] , eth->h_source[2] , eth->h_source[3] ,
eth->h_source[4] , eth->h_source[5] );
fprintf(logfile , " |-Protocol : %u \n",(unsigned short)eth->h_proto);
}
void print_ip_header(unsigned char* Buffer, int Size)
{
print_ethernet_header(Buffer , Size);
unsigned short iphdrlen;
struct iphdr *iph = (struct iphdr *)(Buffer + sizeof(struct ethhdr) );
iphdrlen =iph->ihl*4;
memset(&source, 0, sizeof(source));
source.sin_addr.s_addr = iph->saddr;
memset(&dest, 0, sizeof(dest));
dest.sin_addr.s_addr = iph->daddr;
fprintf(logfile , "\n");
fprintf(logfile , "IP Header\n");
fprintf(logfile , " |-IP Version : %d\n",(unsigned int)iph->version);
fprintf(logfile , " |-Type Of Service : %d\n",(unsigned int)iph->tos);
fprintf(logfile , " |-IP Total Length : %d Bytes(Size ofPacket)",
ntohs(iph->tot_len));
fprintf(logfile , " |-Identification : %d\n",ntohs(iph->id));
fprintf(logfile , " |-TTL : %d\n",(unsigned int)iph->ttl);
fprintf(logfile , " |-Protocol : %d\n",(unsigned int)iph->protocol);
fprintf(logfile , " |-Checksum : %d\n",ntohs(iph->check));
fprintf(logfile , " |-Source IP : %s\n",inet_ntoa(source.sin_addr));
fprintf(logfile , " |-Destination IP : %s\n",inet_ntoa(dest.sin_addr));
}
void print_tcp_packet(unsigned char* Buffer, int Size)
{
unsigned short iphdrlen;
struct iphdr *iph = (struct iphdr *)( Buffer + sizeof(struct ethhdr) );
iphdrlen = iph->ihl*4;
struct tcphdr *tcph=(struct tcphdr*)(Buffer + iphdrlen + sizeof(struct ethhdr));
int header_size = sizeof(struct ethhdr) + iphdrlen + tcph->doff*4;
fprintf(logfile , "\n\n***********************TCP Packet*************************\n");
print_ip_header(Buffer,Size);
fprintf(logfile , "\n");
fprintf(logfile , "TCP Header\n");
fprintf(logfile , " |-Source Port : %u\n",ntohs(tcph->source));
fprintf(logfile , " |-Destination Port : %u\n",ntohs(tcph->dest));
fprintf(logfile , " |-Sequence Number : %u\n",ntohl(tcph->seq));
fprintf(logfile , " |-Acknowledge Number : %u\n",ntohl(tcph->ack_seq));
fprintf(logfile , " |-Header Length : %d DWORDS or %d BYTES\n" ,(unsigned i
fprintf(logfile , " |-Urgent Flag : %d\n",(unsigned int)tcph->urg);
fprintf(logfile , " |-Acknowledgement Flag : %d\n",(unsigned int)tcph->ack);
fprintf(logfile , " |-Push Flag : %d\n",(unsigned int)tcph->psh);
fprintf(logfile , " |-Reset Flag : %d\n",(unsigned int)tcph->rst);
fprintf(logfile , " |-Synchronise Flag : %d\n",(unsigned int)tcph->syn);
fprintf(logfile , " |-Finish Flag : %d\n",(unsigned int)tcph->fin);
fprintf(logfile , " |-Window : %d\n",ntohs(tcph->window));
fprintf(logfile , " |-Checksum : %d\n",ntohs(tcph->check));
fprintf(logfile , " |-Urgent Pointer : %d\n",tcph->urg_ptr);
fprintf(logfile , "\n");
fprintf(logfile , " DATA Dump ");
fprintf(logfile , "\n");
fprintf(logfile , "IP Header\n");
PrintData(Buffer,iphdrlen);
fprintf(logfile , "TCP Header\n");
PrintData(Buffer+iphdrlen,tcph->doff*4);
fprintf(logfile , "Data Payload\n");
PrintData(Buffer + header_size , Size - header_size );
fprintf(logfile , "\n###########################################################");
}
void print_udp_packet(unsigned char *Buffer , int Size)
{
unsigned short iphdrlen;
struct iphdr *iph = (struct iphdr *)(Buffer + sizeof(struct ethhdr));
iphdrlen = iph->ihl*4;
struct udphdr *udph = (struct udphdr*)(Buffer + iphdrlen + sizeof(struct ethhdr));
int header_size = sizeof(struct ethhdr) + iphdrlen + sizeof udph;
fprintf(logfile , "\n\n***********************UDP Packet*************************\n");
print_ip_header(Buffer,Size);
fprintf(logfile , "\nUDP Header\n");
fprintf(logfile , " |-Source Port : %d\n" , ntohs(udph->source));
fprintf(logfile , " |-Destination Port : %d\n" , ntohs(udph->dest));
fprintf(logfile , " |-UDP Length : %d\n" , ntohs(udph->len));
fprintf(logfile , " |-UDP Checksum : %d\n" , ntohs(udph->check));
fprintf(logfile , "\n");
fprintf(logfile , "IP Header\n");
PrintData(Buffer , iphdrlen);
fprintf(logfile , "UDP Header\n");
PrintData(Buffer+iphdrlen , sizeof udph);
fprintf(logfile , "Data Payload\n");
//Move the pointer ahead and reduce the size of string
PrintData(Buffer + header_size , Size - header_size);
fprintf(logfile , "\n###########################################################");
}
void print_icmp_packet(unsigned char* Buffer , int Size)
{
unsigned short iphdrlen;
struct iphdr *iph = (struct iphdr *)(Buffer + sizeof(struct ethhdr));
iphdrlen = iph->ihl * 4;
struct icmphdr *icmph = (struct icmphdr *)(Buffer + iphdrlen + sizeof(struct ethhdr));
int header_size = sizeof(struct ethhdr) + iphdrlen + sizeof icmph;
fprintf(logfile , "\n\n***********************ICMP Packet*************************\n");
print_ip_header(Buffer , Size);
fprintf(logfile , "\n");
fprintf(logfile , "ICMP Header\n");
fprintf(logfile , " |-Type : %d",(unsigned int)(icmph->type));
if((unsigned int)(icmph->type) == 11)
{
fprintf(logfile , " (TTL Expired)\n");
}
else if((unsigned int)(icmph->type) == ICMP_ECHOREPLY)
{
fprintf(logfile , " (ICMP Echo Reply)\n");
}
fprintf(logfile , " |-Code : %d\n",(unsigned int)(icmph->code));
fprintf(logfile , " |-Checksum : %d\n",ntohs(icmph->checksum));
//fprintf(logfile , " |-ID : %d\n",ntohs(icmph->id));
//fprintf(logfile , " |-Sequence : %d\n",ntohs(icmph->sequence));
fprintf(logfile , "\n");
fprintf(logfile , "IP Header\n");
PrintData(Buffer,iphdrlen);
fprintf(logfile , "UDP Header\n");
PrintData(Buffer + iphdrlen , sizeof icmph);
fprintf(logfile , "Data Payload\n");
//Move the pointer ahead and reduce the size of string
PrintData(Buffer + header_size , (Size - header_size) );
fprintf(logfile , "\n###########################################################");
}
int gopromiscous()
{
int fd;
struct ifreq eth;
fd = socket(AF_INET, SOCK_PACKET, htons(0x800));
strcpy(eth.ifr_name, "eth0");
ioctl(fd, SIOCGIFFLAGS, ð);
eth.ifr_flags |= IFF_PROMISC;
ioctl(fd, SIOCSIFFLAGS, ð);
printf("\n Entered Promiscuous Mode Successfully\n");
}
void PrintData (unsigned char* data , int Size)
{
int i , j;
for(i=0 ; i < Size ; i++)
{
if( i!=0 && i%16==0) //if one line of hex printing is complete...
{
fprintf(logfile , " ");
for(j=i-16 ; j<i ; j++)
{
if(data[j]>=32 && data[j]<=128)
fprintf(logfile , "%c",(unsigned char)data[j]);
else fprintf(logfile , ".");
}
fprintf(logfile , "\n");
}
if(i%16==0) fprintf(logfile , " ");
fprintf(logfile , " %02X",(unsigned int)data[i]);
if( i==Size-1) //print the last spaces
{
for(j=0;j<15-i%16;j++)
{
fprintf(logfile , " "); //extra spaces
}
fprintf(logfile , " ");
for(j=i-i%16 ; j<=i ; j++)
{
if(data[j]>=32 && data[j]<=128)
{
fprintf(logfile , "%c",(unsigned char)data[j]);
}
else
{
fprintf(logfile , ".");
}
}
fprintf(logfile , "\n" );
}
}
}
答案 0 :(得分：1)
"wb"作为模式参数fopen()）。使用fwrite()将数据写入日志文件：
if (fwrite(buffer, data_size, 1, logfile) != 1)
...short write...problems...
关闭日志文件。
请注意，在Unix系统上，b标志是可选的（它没有任何危害，但它也没有任何好处）。在Windows上，b标志很重要。对于可移植代码，请使用b标志打开二进制文件。
答案 1 :(得分：1)
logfile = fopen("sniff_data.txt","wb");
“wb”以二进制模式写入。