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