1/*
2 * ipsend.c (C) 1995-1998 Darren Reed
3 *
4 * See the IPFILTER.LICENCE file for details on licencing.
5 */
6#include <sys/param.h>
7#include <sys/types.h>
8#include <sys/time.h>
9#include <sys/socket.h>
10#include <netinet/in.h>
11#include <arpa/inet.h>
12#include <netinet/in_systm.h>
13#include <stdio.h>
14#include <stdlib.h>
15#include <unistd.h>
16#include <netdb.h>
17#include <string.h>
18#include <netinet/ip.h>
19# include <netinet/ip_var.h>
20#include "ipsend.h"
21#include "ipf.h"
22# include <netinet/udp_var.h>
23
24
25extern	char	*optarg;
26extern	int	optind;
27extern	void	iplang(FILE *);
28
29char	options[68];
30int	opts;
31char	default_device[] = "le0";
32
33
34static	void	usage(char *);
35static	void	do_icmp(ip_t *, char *);
36void udpcksum(ip_t *, struct udphdr *, int);
37int	main(int, char **);
38
39
40static	void	usage(prog)
41	char	*prog;
42{
43	fprintf(stderr, "Usage: %s [options] dest [flags]\n\
44\toptions:\n\
45\t\t-d\tdebug mode\n\
46\t\t-i device\tSend out on this device\n\
47\t\t-f fragflags\tcan set IP_MF or IP_DF\n\
48\t\t-g gateway\tIP gateway to use if non-local dest.\n\
49\t\t-I code,type[,gw[,dst[,src]]]\tSet ICMP protocol\n\
50\t\t-m mtu\t\tfake MTU to use when sending out\n\
51\t\t-P protocol\tSet protocol by name\n\
52\t\t-s src\t\tsource address for IP packet\n\
53\t\t-T\t\tSet TCP protocol\n\
54\t\t-t port\t\tdestination port\n\
55\t\t-U\t\tSet UDP protocol\n\
56\t\t-v\tverbose mode\n\
57\t\t-w <window>\tSet the TCP window size\n\
58", prog);
59	fprintf(stderr, "Usage: %s [-dv] -L <filename>\n\
60\toptions:\n\
61\t\t-d\tdebug mode\n\
62\t\t-L filename\tUse IP language for sending packets\n\
63\t\t-v\tverbose mode\n\
64", prog);
65	exit(1);
66}
67
68
69static
70void do_icmp(ip_t *ip, char *args)
71{
72	struct	icmp	*ic;
73	char	*s;
74
75	ip->ip_p = IPPROTO_ICMP;
76	ip->ip_len += sizeof(*ic);
77	ic = (struct icmp *)(ip + 1);
78	bzero((char *)ic, sizeof(*ic));
79	if (!(s = strchr(args, ',')))
80	    {
81		fprintf(stderr, "ICMP args missing: ,\n");
82		return;
83	    }
84	*s++ = '\0';
85	ic->icmp_type = atoi(args);
86	ic->icmp_code = atoi(s);
87	if (ic->icmp_type == ICMP_REDIRECT && strchr(s, ','))
88	    {
89		char	*t;
90
91		t = strtok(s, ",");
92		t = strtok(NULL, ",");
93		if (resolve(t, (char *)&ic->icmp_gwaddr) == -1)
94		    {
95			fprintf(stderr,"Cant resolve %s\n", t);
96			exit(2);
97		    }
98		if ((t = strtok(NULL, ",")))
99		    {
100			if (resolve(t, (char *)&ic->icmp_ip.ip_dst) == -1)
101			    {
102				fprintf(stderr,"Cant resolve %s\n", t);
103				exit(2);
104			    }
105			if ((t = strtok(NULL, ",")))
106			    {
107				if (resolve(t,
108					    (char *)&ic->icmp_ip.ip_src) == -1)
109				    {
110					fprintf(stderr,"Cant resolve %s\n", t);
111					exit(2);
112				    }
113			    }
114		    }
115	    }
116}
117
118
119int
120send_packets(char *dev, int mtu, ip_t *ip, struct in_addr gwip)
121{
122	int wfd;
123
124	wfd = initdevice(dev, 5);
125	if (wfd == -1)
126		return (-1);
127	return (send_packet(wfd, mtu, ip, gwip));
128}
129
130void
131udpcksum(ip_t *ip, struct udphdr *udp, int len)
132{
133	union pseudoh {
134		struct hdr {
135			u_short len;
136			u_char ttl;
137			u_char proto;
138			u_32_t src;
139			u_32_t dst;
140		} h;
141		u_short w[6];
142	} ph;
143	u_32_t temp32;
144	u_short *opts;
145
146	ph.h.len = htons(len);
147	ph.h.ttl = 0;
148	ph.h.proto = IPPROTO_UDP;
149	ph.h.src = ip->ip_src.s_addr;
150	ph.h.dst = ip->ip_dst.s_addr;
151	temp32 = 0;
152	opts = &ph.w[0];
153	temp32 += opts[0] + opts[1] + opts[2] + opts[3] + opts[4] + opts[5];
154	temp32 = (temp32 >> 16) + (temp32 & 65535);
155	temp32 += (temp32 >> 16);
156	udp->uh_sum = temp32 & 65535;
157	udp->uh_sum = chksum((u_short *)udp, len);
158	if (udp->uh_sum == 0)
159		udp->uh_sum = 0xffff;
160}
161
162int
163main(int argc, char **argv)
164{
165	FILE	*langfile = NULL;
166	struct	in_addr	gwip;
167	tcphdr_t	*tcp;
168	udphdr_t	*udp;
169	ip_t	*ip;
170	char	*name =  argv[0], host[MAXHOSTNAMELEN + 1];
171	char	*gateway = NULL, *dev = NULL;
172	char	*src = NULL, *dst, *s;
173	int	mtu = 1500, olen = 0, c, nonl = 0;
174
175	/*
176	 * 65535 is maximum packet size...you never know...
177	 */
178	ip = (ip_t *)calloc(1, 65536);
179	tcp = (tcphdr_t *)(ip + 1);
180	udp = (udphdr_t *)tcp;
181	ip->ip_len = sizeof(*ip);
182	IP_HL_A(ip, sizeof(*ip) >> 2);
183
184	while ((c = getopt(argc, argv, "I:L:P:TUdf:i:g:m:o:s:t:vw:")) != -1) {
185		switch (c)
186		{
187		case 'I' :
188			nonl++;
189			if (ip->ip_p)
190			    {
191				fprintf(stderr, "Protocol already set: %d\n",
192					ip->ip_p);
193				break;
194			    }
195			do_icmp(ip, optarg);
196			break;
197		case 'L' :
198			if (nonl) {
199				fprintf(stderr,
200					"Incorrect usage of -L option.\n");
201				usage(name);
202			}
203			if (!strcmp(optarg, "-"))
204				langfile = stdin;
205			else if (!(langfile = fopen(optarg, "r"))) {
206				fprintf(stderr, "can't open file %s\n",
207					optarg);
208				exit(1);
209			}
210			iplang(langfile);
211			return (0);
212		case 'P' :
213		    {
214			struct	protoent	*p;
215
216			nonl++;
217			if (ip->ip_p)
218			    {
219				fprintf(stderr, "Protocol already set: %d\n",
220					ip->ip_p);
221				break;
222			    }
223			if ((p = getprotobyname(optarg)))
224				ip->ip_p = p->p_proto;
225			else
226				fprintf(stderr, "Unknown protocol: %s\n",
227					optarg);
228			break;
229		    }
230		case 'T' :
231			nonl++;
232			if (ip->ip_p)
233			    {
234				fprintf(stderr, "Protocol already set: %d\n",
235					ip->ip_p);
236				break;
237			    }
238			ip->ip_p = IPPROTO_TCP;
239			ip->ip_len += sizeof(tcphdr_t);
240			break;
241		case 'U' :
242			nonl++;
243			if (ip->ip_p)
244			    {
245				fprintf(stderr, "Protocol already set: %d\n",
246					ip->ip_p);
247				break;
248			    }
249			ip->ip_p = IPPROTO_UDP;
250			ip->ip_len += sizeof(udphdr_t);
251			break;
252		case 'd' :
253			opts |= OPT_DEBUG;
254			break;
255		case 'f' :
256			nonl++;
257			ip->ip_off = strtol(optarg, NULL, 0);
258			break;
259		case 'g' :
260			nonl++;
261			gateway = optarg;
262			break;
263		case 'i' :
264			nonl++;
265			dev = optarg;
266			break;
267		case 'm' :
268			nonl++;
269			mtu = atoi(optarg);
270			if (mtu < 28)
271			    {
272				fprintf(stderr, "mtu must be > 28\n");
273				exit(1);
274			    }
275			break;
276		case 'o' :
277			nonl++;
278			olen = buildopts(optarg, options, (IP_HL(ip) - 5) << 2);
279			break;
280		case 's' :
281			nonl++;
282			src = optarg;
283			break;
284		case 't' :
285			nonl++;
286			if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_UDP)
287				tcp->th_dport = htons(atoi(optarg));
288			break;
289		case 'v' :
290			opts |= OPT_VERBOSE;
291			break;
292		case 'w' :
293			nonl++;
294			if (ip->ip_p == IPPROTO_TCP)
295				tcp->th_win = atoi(optarg);
296			else
297				fprintf(stderr, "set protocol to TCP first\n");
298			break;
299		default :
300			fprintf(stderr, "Unknown option \"%c\"\n", c);
301			usage(name);
302		}
303	}
304
305	if (argc - optind < 1)
306		usage(name);
307	dst = argv[optind++];
308
309	if (!src)
310	    {
311		gethostname(host, sizeof(host));
312		src = host;
313	    }
314
315	if (resolve(src, (char *)&ip->ip_src) == -1)
316	    {
317		fprintf(stderr,"Cant resolve %s\n", src);
318		exit(2);
319	    }
320
321	if (resolve(dst, (char *)&ip->ip_dst) == -1)
322	    {
323		fprintf(stderr,"Cant resolve %s\n", dst);
324		exit(2);
325	    }
326
327	if (!gateway)
328		gwip = ip->ip_dst;
329	else if (resolve(gateway, (char *)&gwip) == -1)
330	    {
331		fprintf(stderr,"Cant resolve %s\n", gateway);
332		exit(2);
333	    }
334
335	if (olen)
336	    {
337		int hlen;
338		char *p;
339
340		printf("Options: %d\n", olen);
341		hlen = sizeof(*ip) + olen;
342		IP_HL_A(ip, hlen >> 2);
343		ip->ip_len += olen;
344		p = (char *)malloc(65536);
345		if (p == NULL)
346		    {
347			fprintf(stderr, "malloc failed\n");
348			exit(2);
349		    }
350
351		bcopy(ip, p, sizeof(*ip));
352		bcopy(options, p + sizeof(*ip), olen);
353		bcopy(ip + 1, p + hlen, ip->ip_len - hlen);
354		ip = (ip_t *)p;
355
356		if (ip->ip_p == IPPROTO_TCP) {
357			tcp = (tcphdr_t *)(p + hlen);
358		} else if (ip->ip_p == IPPROTO_UDP) {
359			udp = (udphdr_t *)(p + hlen);
360		}
361	    }
362
363	if (ip->ip_p == IPPROTO_TCP)
364		for (s = argv[optind]; s && (c = *s); s++)
365			switch(c)
366			{
367			case 'S' : case 's' :
368				tcp->th_flags |= TH_SYN;
369				break;
370			case 'A' : case 'a' :
371				tcp->th_flags |= TH_ACK;
372				break;
373			case 'F' : case 'f' :
374				tcp->th_flags |= TH_FIN;
375				break;
376			case 'R' : case 'r' :
377				tcp->th_flags |= TH_RST;
378				break;
379			case 'P' : case 'p' :
380				tcp->th_flags |= TH_PUSH;
381				break;
382			case 'U' : case 'u' :
383				tcp->th_flags |= TH_URG;
384				break;
385			}
386
387	if (!dev)
388		dev = default_device;
389	printf("Device:  %s\n", dev);
390	printf("Source:  %s\n", inet_ntoa(ip->ip_src));
391	printf("Dest:    %s\n", inet_ntoa(ip->ip_dst));
392	printf("Gateway: %s\n", inet_ntoa(gwip));
393	if (ip->ip_p == IPPROTO_TCP && tcp->th_flags)
394		printf("Flags:   %#x\n", tcp->th_flags);
395	printf("mtu:     %d\n", mtu);
396
397	if (ip->ip_p == IPPROTO_UDP) {
398		udp->uh_sum = 0;
399		udpcksum(ip, udp, ip->ip_len - (IP_HL(ip) << 2));
400	}
401#ifdef	DOSOCKET
402	if (ip->ip_p == IPPROTO_TCP && tcp->th_dport)
403		return (do_socket(dev, mtu, ip, gwip));
404#endif
405	return (send_packets(dev, mtu, ip, gwip));
406}
407