1 2 /* 3 * resend.c (C) 1995-1998 Darren Reed 4 * 5 * See the IPFILTER.LICENCE file for details on licencing. 6 * 7 */ 8 #include <sys/param.h> 9 #include <sys/types.h> 10 #include <sys/time.h> 11 #include <sys/socket.h> 12 #include <net/if.h> 13 #include <netinet/in.h> 14 #include <arpa/inet.h> 15 #include <netinet/in_systm.h> 16 #include <netinet/ip.h> 17 # include <netinet/ip_var.h> 18 # include <netinet/if_ether.h> 19 #include <stdio.h> 20 #include <netdb.h> 21 #include <string.h> 22 #include <stdlib.h> 23 #include <unistd.h> 24 #include "ipsend.h" 25 26 extern int opts; 27 28 void dumppacket(ip_t *); 29 30 31 void 32 dumppacket(ip_t *ip) 33 { 34 tcphdr_t *t; 35 int i, j; 36 37 t = (tcphdr_t *)((char *)ip + (IP_HL(ip) << 2)); 38 if (ip->ip_tos) 39 printf("tos %#x ", ip->ip_tos); 40 if (ip->ip_off & 0x3fff) 41 printf("frag @%#x ", (ip->ip_off & 0x1fff) << 3); 42 printf("len %d id %d ", ip->ip_len, ip->ip_id); 43 printf("ttl %d p %d src %s", ip->ip_ttl, ip->ip_p, 44 inet_ntoa(ip->ip_src)); 45 if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP) 46 printf(",%d", t->th_sport); 47 printf(" dst %s", inet_ntoa(ip->ip_dst)); 48 if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP) 49 printf(",%d", t->th_dport); 50 if (ip->ip_p == IPPROTO_TCP) { 51 printf(" seq %lu:%lu flags ", 52 (u_long)t->th_seq, (u_long)t->th_ack); 53 for (j = 0, i = 1; i < 256; i *= 2, j++) 54 if (t->th_flags & i) 55 printf("%c", "FSRPAU--"[j]); 56 } 57 putchar('\n'); 58 } 59 60 61 int 62 ip_resend(char *dev, int mtu, struct ipread *r, struct in_addr gwip, 63 char *datain) 64 { 65 ether_header_t *eh; 66 char dhost[6]; 67 ip_t *ip; 68 int fd, wfd = initdevice(dev, 5), len, i; 69 mb_t mb; 70 71 if (wfd == -1) 72 return (-1); 73 74 if (datain) 75 fd = (*r->r_open)(datain); 76 else 77 fd = (*r->r_open)("-"); 78 79 if (fd < 0) 80 exit(-1); 81 82 ip = (struct ip *)mb.mb_buf; 83 eh = (ether_header_t *)malloc(sizeof(*eh)); 84 if(!eh) 85 { 86 perror("malloc failed"); 87 return (-2); 88 } 89 90 bzero((char *) &eh->ether_shost, sizeof(eh->ether_shost)); 91 if (gwip.s_addr && (arp((char *)&gwip, dhost) == -1)) 92 { 93 perror("arp"); 94 free(eh); 95 return (-2); 96 } 97 98 while ((i = (*r->r_readip)(&mb, NULL, NULL)) > 0) 99 { 100 if (!(opts & OPT_RAW)) { 101 len = ntohs(ip->ip_len); 102 eh = (ether_header_t *)realloc((char *)eh, sizeof(*eh) + len); 103 eh->ether_type = htons((u_short)ETHERTYPE_IP); 104 if (!gwip.s_addr) { 105 if (arp((char *)&gwip, 106 (char *) &eh->ether_dhost) == -1) { 107 perror("arp"); 108 continue; 109 } 110 } else 111 bcopy(dhost, (char *) &eh->ether_dhost, 112 sizeof(dhost)); 113 if (!ip->ip_sum) 114 ip->ip_sum = chksum((u_short *)ip, 115 IP_HL(ip) << 2); 116 bcopy(ip, (char *)(eh + 1), len); 117 len += sizeof(*eh); 118 dumppacket(ip); 119 } else { 120 eh = (ether_header_t *)mb.mb_buf; 121 len = i; 122 } 123 124 if (sendip(wfd, (char *)eh, len) == -1) 125 { 126 perror("send_packet"); 127 break; 128 } 129 } 130 (*r->r_close)(); 131 free(eh); 132 return (0); 133 } 134