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
dumppacket(ip_t * ip)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
ip_resend(char * dev,int mtu,struct ipread * r,struct in_addr gwip,char * datain)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