427.htm

unix高级编程原吗

        printf("Src Port : %d, Dst Port : %d, Message Length : %d\n", <br>
                ntohs(uhdr->source), ntohs(uhdr->dest), ntohs(uhdr->len)); <br>
} <br>
} <br>
void leave(int signo) <br>
{ <br>
        ifr_old.ifr_flags &= ~IFF_PROMISC; <br>
        if( ioctl(sock_pak, SIOCSIFFLAGS, &ifr_old) < 0 ) <br>
        { <br>
                perror("Restore IFF_PROMISC"); <br>
                exit(-1); <br>
        } <br>
        setuid(getuid()); <br>
        exit(0); <br>
} <br>
int main(int argc, char *argv[]) <br>
{ <br>
        struct ifreq ifr; <br>
        struct sockaddr_in sa_from; <br>
        struct ethhdr *ehdr; <br>
        struct iphdr *ip_hdr; <br>
        struct arp_hdr *ahdr; <br>
        struct in_addr dst_addr, src_addr; <br>
        u_char recvbuf[32*1024]; <br>
        char str_hw1[32], str_hw2[32], str_flag[128], str_src[32], str_dst[3 <br>
2]; <br>
2]; <br>
        int n, i, sa_len; <br>
        if( (sock_pak = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL))) < 0) <br>
        { <br>
                perror("Socket"); <br>
                exit(-1); <br>
        } <br>
        strcpy(ifr.ifr_name, "eth0"); <br>
        if( ioctl(sock_pak, SIOCGIFFLAGS, &ifr) < 0 ) <br>
        { <br>
                perror("Ioctl SIOCGIFFLAGS"); <br>
                exit(-1); <br>
        } <br>
        ifr_old = ifr; <br>
        ifr.ifr_flags |= IFF_PROMISC; <br>
        if( ioctl(sock_pak, SIOCSIFFLAGS, &ifr) < 0 ) <br>
        { <br>
                perror("Ioctl SIOCSIFFLAGS"); <br>
                exit(-1); <br>
        } <br>
        signal(SIGINT, leave); <br>
        signal(SIGTERM, leave); <br>
        for(i=0; i<80; i++) <br>

                printf("+"); <br>
        printf("\nSnoopy's nose begins to work now!\n"); <br>
        for(i=0; i<80; i++) <br>
                printf("+"); <br>
        printf("\n\n"); <br>
        while(1) <br>
        { <br>
                sa_len = sizeof(sa_from); <br>
                bzero(&sa_from, sa_len); <br>
                if ( (n = recvfrom(sock_pak, recvbuf, sizeof(recvbuf), 0, &s <br>
a_fr <br>
om, &sa_len)) < 0) <br>
                        perror("Recvfrom"); <br>
                recvbuf[n] = 0; <br>
                ehdr = (struct ethhdr *)recvbuf; <br>
                for(i=0; i<80; i++) <br>
                        printf("*"); <br>
                if( ntohs(ehdr->h_proto) == 0x0800 ) //IP datagram <br>
                { <br>
                        printf("\nIPv4 datagram from %s to %s\n", hw_addr(eh <br>
dr-> <br>
h_source, str_hw1), <br>

                                hw_addr(ehdr->h_dest, str_hw2)); <br>
                        printf("\nIP Header Analysis:\n"); <br>
                        ip_hdr = (struct iphdr*)(recvbuf + sizeof(struct eth <br>
hdr) <br>
); <br>
                        printf("Ver : 4, HLen : %d, Type Of Service : %d, To <br>
tal <br>
Length : %d\n", <br>
                                ip_hdr->ihl, ip_hdr->tos, ntohs(ip_hdr->tot_ <br>
len) <br>
); <br>
                        printf("Id : %d, %s\n", ntohs(ip_hdr->id), ip_flag(i <br>
p_hd <br>
r->frag_off, str_flag)); <br>
                        dst_addr.s_addr = ip_hdr->daddr; <br>
                        src_addr.s_addr = ip_hdr->saddr; <br>
                        strcpy( str_src, inet_ntoa(src_addr)); <br>
                        strcpy( str_dst, inet_ntop(AF_INET, &dst_addr, str_f <br>
lag, <br>
 sizeof(str_flag))); <br>
                        printf("Src IP : %s, Dst IP : %s, Protocol : %s\n", <br>
                                str_src, str_dst, ip_proto(ip_hdr->protocol, <br>

 str <br>
_flag)); <br>
                        switch( ip_hdr->protocol ) <br>
                        { <br>
                                case 1: <br>
                                        dealICMP(recvbuf, n); <br>
                                        break; <br>
                                case 2: <br>
                                        dealIGMP(recvbuf, n); <br>
                                        break; <br>
                                case 6: <br>
                                        dealTCP(recvbuf, n); <br>
                                        break; <br>
                                case 17: <br>
                                        dealUDP(recvbuf, n); <br>
                                        break; <br>
                                default: <br>
                                        break; <br>
                        } <br>
                } <br>
                else if( ntohs(ehdr->h_proto) == 0x0806 ) //ARP datagram <br>
                { <br>

                        printf("\nARP datagram from %s to %s\n", hw_addr(ehd <br>
r->h <br>
_source, str_hw1), <br>
                                hw_addr(ehdr->h_dest, str_hw2)); <br>
                        ahdr = (struct arp_hdr*)recvbuf; <br>
                        printf("HW type : %d, Proto : %d, HW Addr Len : %d, <br>
Prot <br>
o Addr Len : %d\n", <br>
                                ntohs(ahdr->hw_type), ntohs(ahdr->proto_type <br>
), <br>
                                ahdr->hw_addr_len, ahdr->proto_addr_len); <br>
                        switch( ntohs(ahdr->op) ) <br>
                        { <br>
                                case 1: <br>
                                        printf("Operation : ARP Request\n"); <br>
  <br>
                                        break; <br>
                                case 2: <br>
                                        printf("Operation : ARP Reply\n"); <br>
                                        break; <br>
                                case 3: <br>
                                        printf("Operation : RARP Request\n") <br>

; <br>
                                        break; <br>
                                case 4: <br>
                                        printf("Operation : RARP Reply\n"); <br>
                                        break; <br>
                                default: <br>
                                        printf("Operation : %d\n", ntohs(ahd <br>
r->o <br>
p)); <br>
                                        break; <br>
                        } <br>
                        printf("Sender HW : %s, Receiver HW : %s\n", <br>
                                hw_addr(ahdr->snd_hw_addr, str_hw1), <br>
                                hw_addr(ahdr->rcv_hw_addr, str_hw2)); <br>
                        memcpy(&dst_addr, ahdr->rcv_ip_addr, IP_HLEN); <br>
                        memcpy(&src_addr, ahdr->snd_ip_addr, IP_HLEN); <br>
                        strcpy( str_src, inet_ntoa(src_addr)); <br>
                        strcpy( str_dst, inet_ntop(AF_INET, &dst_addr, str_f <br>
lag, <br>
 sizeof(str_flag))); <br>
                        printf("Sender IP : %s, Receiver IP : %s\n", str_src <br>
, st <br>
, st <br>
r_dst); <br>
                } <br>
                else <br>
                { <br>
                        printf("\n? datagram from %s to %s type %.4x\n", hw_ <br>
addr <br>
(ehdr->h_source, str_hw1), <br>
                                hw_addr(ehdr->h_dest, str_hw2), htons(ehdr-> <br>
h_pr <br>
oto)); <br>
                } <br>
                for(i=0; i<80; i++) <br>
                        printf("-"); <br>
                printf("\n\n"); <br>
        } <br>
        return 0; <br>
} <br>
  Wish your sky be sunny, <br>
   Wish your heart be happy, <br>
    Wish your body be healthy, <br>
     Wish U never be lazy. <br>
  :) :> ;) ;> :-) :-> ;-) ;-> <br>

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