1/*	$FreeBSD$	*/
2
3/*
4 * Copyright (C) 2012 by Darren Reed.
5 *
6 * See the IPFILTER.LICENCE file for details on licencing.
7 */
8#if !defined(lint)
9static const char sccsid[] = "@(#)ip_fil.c	2.41 6/5/96 (C) 1993-2000 Darren Reed";
10static const char rcsid[] = "@(#)$Id$";
11#endif
12#include <sys/types.h>
13#include <sys/time.h>
14#include <sys/socket.h>
15
16#include <netinet/in.h>
17#include <net/if.h>
18
19#include <arpa/inet.h>
20
21#include <stdio.h>
22#include <stdlib.h>
23#include <fcntl.h>
24#include <string.h>
25#include <unistd.h>
26#include <syslog.h>
27#include <errno.h>
28#include <signal.h>
29
30#include "netinet/ip_compat.h"
31#include "netinet/ip_fil.h"
32#include "netinet/ip_state.h"
33#include "netinet/ip_nat.h"
34#include "netinet/ip_sync.h"
35
36int	main __P((int, char *[]));
37void	usage __P((const char *progname));
38
39int	terminate = 0;
40
41void usage(const char *progname) {
42	fprintf(stderr,
43		"Usage: %s <destination IP> <destination port> [remote IP]\n",
44		progname);
45}
46
47#if 0
48static void handleterm(int sig)
49{
50	terminate = sig;
51}
52#endif
53
54#define BUFFERLEN 1400
55
56int main(argc, argv)
57	int argc;
58	char *argv[];
59{
60	int nfd = -1 , lfd = -1;
61	int n1, n2, n3, magic, len, inbuf;
62	struct sockaddr_in sin;
63	struct sockaddr_in in;
64	char buff[BUFFERLEN];
65	synclogent_t *sl;
66	syncupdent_t *su;
67	synchdr_t *sh;
68	char *progname;
69
70	progname = strrchr(argv[0], '/');
71	if (progname) {
72		progname++;
73	} else {
74		progname = argv[0];
75	}
76
77	if (argc < 2) {
78		usage(progname);
79		exit(1);
80	}
81
82#if 0
83       	signal(SIGHUP, handleterm);
84       	signal(SIGINT, handleterm);
85       	signal(SIGTERM, handleterm);
86#endif
87
88	openlog(progname, LOG_PID, LOG_SECURITY);
89
90	lfd = open(IPSYNC_NAME, O_WRONLY);
91	if (lfd == -1) {
92		syslog(LOG_ERR, "Opening %s :%m", IPSYNC_NAME);
93		exit(1);
94	}
95
96	bzero((char *)&sin, sizeof(sin));
97	sin.sin_family = AF_INET;
98	if (argc > 1)
99		sin.sin_addr.s_addr = inet_addr(argv[1]);
100	if (argc > 2)
101		sin.sin_port = htons(atoi(argv[2]));
102	else
103		sin.sin_port = htons(43434);
104	if (argc > 3)
105		in.sin_addr.s_addr = inet_addr(argv[3]);
106	else
107		in.sin_addr.s_addr = 0;
108	in.sin_port = 0;
109
110	while(1) {
111
112		if (lfd != -1)
113			close(lfd);
114		if (nfd != -1)
115			close(nfd);
116
117		lfd = open(IPSYNC_NAME, O_WRONLY);
118		if (lfd == -1) {
119			syslog(LOG_ERR, "Opening %s :%m", IPSYNC_NAME);
120			goto tryagain;
121		}
122
123		nfd = socket(AF_INET, SOCK_DGRAM, 0);
124		if (nfd == -1) {
125			syslog(LOG_ERR, "Socket :%m");
126			goto tryagain;
127		}
128
129	        n1 = 1;
130                setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &n1, sizeof(n1));
131
132		if (bind(nfd, (struct sockaddr *)&sin, sizeof(sin)) == -1) {
133			syslog(LOG_ERR, "Bind: %m");
134			goto tryagain;
135		}
136
137		syslog(LOG_INFO, "Listening to %s", inet_ntoa(sin.sin_addr));
138
139		inbuf = 0;
140		while (1) {
141
142
143			/*
144			 * XXX currently we do not check the source address
145			 * of a datagram, this can be a security risk
146			 */
147			n1 = read(nfd, buff+inbuf, BUFFERLEN-inbuf);
148
149			printf("header : %d bytes read (header = %d bytes)\n",
150			       n1, (int) sizeof(*sh));
151
152			if (n1 < 0) {
153				syslog(LOG_ERR, "Read error (header): %m");
154				goto tryagain;
155			}
156
157			if (n1 == 0) {
158				/* XXX can this happen??? */
159				syslog(LOG_ERR,
160				       "Read error (header) : No data");
161				sleep(1);
162				continue;
163			}
164
165			inbuf += n1;
166
167moreinbuf:
168			if (inbuf < sizeof(*sh)) {
169				continue; /* need more data */
170			}
171
172			sh = (synchdr_t *)buff;
173			len = ntohl(sh->sm_len);
174			magic = ntohl(sh->sm_magic);
175
176			if (magic != SYNHDRMAGIC) {
177				syslog(LOG_ERR, "Invalid header magic %x",
178				       magic);
179				goto tryagain;
180			}
181
182#define IPSYNC_DEBUG
183#ifdef IPSYNC_DEBUG
184			printf("v:%d p:%d len:%d magic:%x", sh->sm_v,
185			       sh->sm_p, len, magic);
186
187			if (sh->sm_cmd == SMC_CREATE)
188				printf(" cmd:CREATE");
189			else if (sh->sm_cmd == SMC_UPDATE)
190				printf(" cmd:UPDATE");
191			else
192				printf(" cmd:Unknown(%d)", sh->sm_cmd);
193
194			if (sh->sm_table == SMC_NAT)
195				printf(" table:NAT");
196			else if (sh->sm_table == SMC_STATE)
197				printf(" table:STATE");
198			else
199				printf(" table:Unknown(%d)", sh->sm_table);
200
201			printf(" num:%d\n", (u_32_t)ntohl(sh->sm_num));
202#endif
203
204			if (inbuf < sizeof(*sh) + len) {
205				continue; /* need more data */
206				goto tryagain;
207			}
208
209#ifdef IPSYNC_DEBUG
210			if (sh->sm_cmd == SMC_CREATE) {
211				sl = (synclogent_t *)buff;
212
213			} else if (sh->sm_cmd == SMC_UPDATE) {
214				su = (syncupdent_t *)buff;
215				if (sh->sm_p == IPPROTO_TCP) {
216					printf(" TCP Update: age %lu state %d/%d\n",
217					       su->sup_tcp.stu_age,
218					       su->sup_tcp.stu_state[0],
219					       su->sup_tcp.stu_state[1]);
220				}
221			} else {
222				printf("Unknown command\n");
223			}
224#endif
225
226			n2 = sizeof(*sh) + len;
227			n3 = write(lfd, buff, n2);
228			if (n3 <= 0) {
229				syslog(LOG_ERR, "%s: Write error: %m",
230				       IPSYNC_NAME);
231				goto tryagain;
232			}
233
234
235			if (n3 != n2) {
236				syslog(LOG_ERR, "%s: Incomplete write (%d/%d)",
237				       IPSYNC_NAME, n3, n2);
238				goto tryagain;
239			}
240
241			/* signal received? */
242			if (terminate)
243				break;
244
245			/* move buffer to the front,we might need to make
246			 * this more efficient, by using a rolling pointer
247			 * over the buffer and only copying it, when
248			 * we are reaching the end
249			 */
250			inbuf -= n2;
251			if (inbuf) {
252				bcopy(buff+n2, buff, inbuf);
253				printf("More data in buffer\n");
254				goto moreinbuf;
255			}
256		}
257
258		if (terminate)
259			break;
260tryagain:
261		sleep(1);
262	}
263
264
265	/* terminate */
266	if (lfd != -1)
267		close(lfd);
268	if (nfd != -1)
269		close(nfd);
270
271	syslog(LOG_ERR, "signal %d received, exiting...", terminate);
272
273	exit(1);
274}
275