编写了一个程序，从网络接收数据包并将其保存在名为“sniff_data.bin”的二进制文件中。但在编译过程中，我收到错误“函数 fwrite 的参数太少”。我的程序出了什么问题？有人能帮我解决吗？（在程序中，用于打开二进制文件的处理程序是“logfile”）这是我的代码：
这是我的代码：
void ProcessPacket(unsigned char* , int);
void print_ip_header(unsigned char* , int);
void print_tcp_packet(unsigned char * , int );
void print_udp_packet(unsigned char * , int );
void print_icmp_packet(unsigned char* , int );
void PrintData (unsigned char* , int);
FILE *logfile;
struct sockaddr_in source,dest;
int tcp=0,udp=0,icmp=0,others=0,igmp=0,total=0,i,j;
int main()
{
int saddr_size , data_size;
struct sockaddr saddr;
gopromiscous();
unsigned char *buffer = (unsigned char *) malloc(1024);
logfile=fopen("sniff_data.bin","wb");
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 );
int count=30;
while(count>=0)
{
count--;
saddr_size = sizeof saddr;
//Receive a packet
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;
}
// if (fwrite(buffer, data_size, 1, logfile) != 1)
fwrite(buffer, data_size, 1, logfile);
//Now process the packet
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;
fwrite(logfile , "\n");
fwrite(logfile , "Ethernet Header\n");
fwrite(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] );
fwrite(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] );
fwrite(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;
fwrite(logfile , "\n");
fwrite(logfile , "IP Header\n");
fwrite(logfile , " |-IP Version : %d\n",(unsigned int)iph->version);
fwrite(logfile , " |-IP Header Length : %d DWORDS or %d Bytes\n",(unsigned
int)iph->ihl,((unsigned int)(iph->ihl))*4);
fwrite(logfile , " |-Type Of Service : %d\n",(unsigned int)iph->tos);
fwrite(logfile , " |-IP Total Length : %d Bytes(Size of
Packet)\n",ntohs(iph->tot_len));
fwrite(logfile , " |-Identification : %d\n",ntohs(iph->id));
//fprintf(logfile , " |-Reserved ZERO Field : %d\n",(unsigned
int)iphdr->ip_reserved_zero);
//fprintf(logfile , " |-Dont Fragment Field : %d\n",(unsigned
int)iphdr->ip_dont_fragment);
//fprintf(logfile , " |-More Fragment Field : %d\n",(unsigned
int)iphdr->ip_more_fragment);
fwrite(logfile , " |-TTL : %d\n",(unsigned int)iph->ttl);
fwrite(logfile , " |-Protocol : %d\n",(unsigned int)iph->protocol);
fwrite(logfile , " |-Checksum : %d\n",ntohs(iph->check));
fwrite(logfile , " |-Source IP : %s\n",inet_ntoa(source.sin_addr));
fwrite(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;
fwrite(logfile , "\n\n***********************TCP
Packet*************************\n");
print_ip_header(Buffer,Size);
fwrite(logfile , "\n");
fwrite(logfile , "TCP Header\n");
fwrite(logfile , " |-Source Port : %u\n",ntohs(tcph->source));
fwrite(logfile , " |-Destination Port : %u\n",ntohs(tcph->dest));
fwrite(logfile , " |-Sequence Number : %u\n",ntohl(tcph->seq));
fwrite(logfile , " |-Acknowledge Number : %u\n",ntohl(tcph->ack_seq));
fwrite(logfile , " |-Header Length : %d DWORDS or %d BYTES\n" ,(unsigned
int)tcph->doff,(unsigned int)tcph->doff*4);
//fprintf(logfile , " |-CWR Flag : %d\n",(unsigned int)tcph->cwr);
//fprintf(logfile , " |-ECN Flag : %d\n",(unsigned int)tcph->ece);
fwrite(logfile , " |-Urgent Flag : %d\n",(unsigned int)tcph->urg);
fwrite(logfile , " |-Acknowledgement Flag : %d\n",(unsigned int)tcph->ack);
fwrite(logfile , " |-Push Flag : %d\n",(unsigned int)tcph->psh);
fwrite(logfile , " |-Reset Flag : %d\n",(unsigned int)tcph->rst);
fwrite(logfile , " |-Synchronise Flag : %d\n",(unsigned int)tcph->syn);
fwrite(logfile , " |-Finish Flag : %d\n",(unsigned int)tcph->fin);
fwrite(logfile , " |-Window : %d\n",ntohs(tcph->window));
fwrite(logfile , " |-Checksum : %d\n",ntohs(tcph->check));
fwrite(logfile , " |-Urgent Pointer : %d\n",tcph->urg_ptr);
fwrite(logfile , "\n");
fwrite(logfile , " DATA Dump ");
fwrite(logfile , "\n");
fwrite(logfile , "IP Header\n");
PrintData(Buffer,iphdrlen);
fwrite(logfile , "TCP Header\n");
PrintData(Buffer+iphdrlen,tcph->doff*4);
fwrite(logfile , "Data Payload\n");
PrintData(Buffer + header_size , Size - header_size );
fwrite(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;
fwrite(logfile , "\n\n***********************UDP
Packet*************************\n");
print_ip_header(Buffer,Size);
fwrite(logfile , "\nUDP Header\n");
fwrite(logfile , " |-Source Port : %d\n" , ntohs(udph->source));
fwrite(logfile , " |-Destination Port : %d\n" , ntohs(udph->dest));
fwrite(logfile , " |-UDP Length : %d\n" , ntohs(udph->len));
fwrite(logfile , " |-UDP Checksum : %d\n" , ntohs(udph->check));
fwrite(logfile , "\n");
fwrite(logfile , "IP Header\n");
PrintData(Buffer , iphdrlen);
fwrite(logfile , "UDP Header\n");
PrintData(Buffer+iphdrlen , sizeof udph);
fwrite(logfile , "Data Payload\n");
//Move the pointer ahead and reduce the size of string
PrintData(Buffer + header_size , Size - header_size);
fwrite(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;
fwrite(logfile , "\n\n***********************ICMP
Packet*************************\n");
print_ip_header(Buffer , Size);
fwrite(logfile , "\n");
fwrite(logfile , "ICMP Header\n");
fwrite(logfile , " |-Type : %d",(unsigned int)(icmph->type));
if((unsigned int)(icmph->type) == 11)
{
fwrite(logfile , " (TTL Expired)\n");
}
else if((unsigned int)(icmph->type) == ICMP_ECHOREPLY)
{
fwrite(logfile , " (ICMP Echo Reply)\n");
}
fwrite(logfile , " |-Code : %d\n",(unsigned int)(icmph->code));
fwrite(logfile , " |-Checksum : %d\n",ntohs(icmph->checksum));
//fprintf(logfile , " |-ID : %d\n",ntohs(icmph->id));
//fprintf(logfile , " |-Sequence : %d\n",ntohs(icmph->sequence));
fwrite(logfile , "\n");
fwrite(logfile , "IP Header\n");
PrintData(Buffer,iphdrlen);
fwrite(logfile , "UDP Header\n");
PrintData(Buffer + iphdrlen , sizeof icmph);
fwrite(logfile , "Data Payload\n");
//Move the pointer ahead and reduce the size of string
PrintData(Buffer + header_size , (Size - header_size) );
fwrite(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...
{
fwrite(logfile , " ");
for(j=i-16 ; j<i ; j++)
{
if(data[j]>=32 && data[j]<=128)
fwrite(logfile , "%c",(unsigned char)data[j]); //if its a number or
alphabet
else fwrite(logfile , "."); //otherwise print a dot
}
fwrite(logfile , "\n");
}
if(i%16==0) fwrite(logfile , " ");
fwrite(logfile , " %02X",(unsigned int)data[i]);
if( i==Size-1) //print the last spaces
{
for(j=0;j<15-i%16;j++)
{
fwrite(logfile , " "); //extra spaces
}
fwrite(logfile , " ");
for(j=i-i%16 ; j<=i ; j++)
{
if(data[j]>=32 && data[j]<=128)
{
fwrite(logfile , "%c",(unsigned char)data[j]);
}
else
{
fwrite(logfile , ".");
}
}
fwrite(logfile , "\n" );
}
}
}
答案1
我认为这个论坛不适合回答您的问题，但看起来您混淆了 fwrite 和 fprintf。
fwrite 总是接受 4 个参数，其中没有一个是“％c”或“％s”。
fprintf 始终需要两个参数，但可能具有更多参数，具体取决于格式字符串中指定的参数数量（即“％c ％c ％s”意味着 fprintf 需要 5 个参数——一个用于 FILE*，一个用于格式字符串，三个参数（两个字符和一个字符串）。