xref: /freebsd/usr.sbin/ip6addrctl/ip6addrctl.c (revision b3e7694832e81d7a904a10f525f8797b753bf0d3)
1 /*	$KAME: ip6addrctl.c,v 1.3 2003/12/16 08:14:28 suz Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-3-Clause
5  *
6  * Copyright (C) 2001 WIDE Project.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the project nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/types.h>
35 #include <sys/socket.h>
36 #include <sys/queue.h>
37 #include <sys/param.h>
38 #include <sys/ioctl.h>
39 #include <sys/sysctl.h>
40 
41 #include <net/if.h>
42 
43 #include <netinet/in.h>
44 #include <netinet6/in6_var.h>
45 
46 #include <stdlib.h>
47 #include <netdb.h>
48 #include <stdio.h>
49 #include <unistd.h>
50 #include <limits.h>
51 #include <string.h>
52 #include <err.h>
53 
54 static char *configfile;
55 
56 struct policyqueue {
57 	TAILQ_ENTRY(policyqueue) pc_entry;
58 	struct in6_addrpolicy pc_policy;
59 };
60 TAILQ_HEAD(policyhead, policyqueue);
61 static struct policyhead policyhead;
62 
63 static void usage(void) __dead2;
64 static void get_policy(void);
65 static void dump_policy(void);
66 static int mask2plen(struct sockaddr_in6 *);
67 static int parse_prefix(const char *, struct in6_addrpolicy *);
68 static void make_policy_fromfile(char *);
69 static void plen2mask(struct sockaddr_in6 *, int);
70 static void set_policy(void);
71 static void add_policy(char *, char *, char *);
72 static void delete_policy(char *);
73 static void flush_policy(void);
74 
75 int
main(int argc,char * argv[])76 main(int argc, char *argv[])
77 {
78 	TAILQ_INIT(&policyhead);
79 
80 	if (argc == 1 || strcasecmp(argv[1], "show") == 0) {
81 		get_policy();
82 		dump_policy();
83 	} else if (strcasecmp(argv[1], "add") == 0) {
84 		if (argc < 5)
85 			usage();
86 		add_policy(argv[2], argv[3], argv[4]);
87 	} else if (strcasecmp(argv[1], "delete") == 0) {
88 		if (argc < 3)
89 			usage();
90 		delete_policy(argv[2]);
91 	} else if (strcasecmp(argv[1], "flush") == 0) {
92 		get_policy();
93 		flush_policy();
94 	} else if (strcasecmp(argv[1], "install") == 0) {
95 		if (argc < 3)
96 			usage();
97 		configfile = argv[2];
98 		make_policy_fromfile(configfile);
99 		set_policy();
100 	} else
101 		usage();
102 
103 	exit(0);
104 }
105 
106 static void
get_policy(void)107 get_policy(void)
108 {
109 	int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY };
110 	size_t l;
111 	struct in6_addrpolicy *buf;
112 	struct in6_addrpolicy *pol, *ep;
113 
114 	if (sysctl(mib, nitems(mib), NULL, &l, NULL, 0) < 0) {
115 		err(1, "sysctl(IPV6CTL_ADDRCTLPOLICY)");
116 		/* NOTREACHED */
117 	}
118 	if (l == 0) {
119 		printf("no source-address-selection policy is installed\n");
120 		return;
121 	}
122 	if ((buf = malloc(l)) == NULL) {
123 		errx(1, "malloc failed");
124 		/* NOTREACHED */
125 	}
126 	if (sysctl(mib, nitems(mib), buf, &l, NULL, 0) < 0) {
127 		err(1, "sysctl(IPV6CTL_ADDRCTLPOLICY)");
128 		/* NOTREACHED */
129 	}
130 
131 	ep = buf + l/sizeof(*buf);
132 	for (pol = buf; pol + 1 <= ep; pol++) {
133 		struct policyqueue *new;
134 
135 		if ((new = malloc(sizeof(*new))) == NULL)
136 			errx(1, "malloc failed\n");
137 		new->pc_policy = *pol;
138 		TAILQ_INSERT_TAIL(&policyhead, new, pc_entry);
139 	}
140 
141 	free(buf);
142 }
143 
144 static void
dump_policy(void)145 dump_policy(void)
146 {
147 	size_t addrlen;
148 	char addrbuf[NI_MAXHOST];
149 	struct in6_addrpolicy *pol;
150 	struct policyqueue *ent;
151 	int plen, first = 1;
152 
153 	for (ent = TAILQ_FIRST(&policyhead); ent;
154 	     ent = TAILQ_NEXT(ent, pc_entry)) {
155 		pol = &ent->pc_policy;
156 		if (first) {
157 			printf("%-30s %5s %5s %8s\n",
158 			       "Prefix", "Prec", "Label", "Use");
159 			first = 0;
160 		}
161 
162 		if ((getnameinfo((struct sockaddr *)&pol->addr,
163 				 sizeof(pol->addr), addrbuf, sizeof(addrbuf),
164 				 NULL, 0, NI_NUMERICHOST))) {
165 			warnx("getnameinfo for prefix address failed");
166 			continue;
167 		}
168 		if ((plen = mask2plen(&pol->addrmask)) < 0) {
169 			warnx("invalid address mask");
170 			continue;
171 		}
172 		addrlen = strlen(addrbuf);
173 		if (addrlen + sizeof("/128") < sizeof(addrbuf)) {
174 			snprintf(&addrbuf[addrlen],
175 				 sizeof(addrbuf) - addrlen - 1,
176 				 "/%d", plen);
177 			printf("%-30s", addrbuf);
178 		} else		/* XXX */
179 			printf("%s/%d", addrbuf, plen);
180 		printf(" %5d %5d %8llu\n", pol->preced, pol->label,
181 		    (unsigned long long)pol->use);
182 	}
183 }
184 
185 #define SKIP_WHITE(p, emptyok) \
186 	do { \
187 		while((*(p) == ' ' || *(p) == '\t')) \
188 			(p)++; \
189  		if ((*(p) == '\0' || (*(p) == '\n')) && !(emptyok)) \
190 			goto bad; \
191 	} while (0);
192 #define SKIP_WORD(p) \
193 	do { \
194 		while(*(p) != ' ' && *(p) != '\t') \
195 			(p)++; \
196  		if (*(p) == '\0' || *(p) == '\n') \
197 			goto bad; \
198 	} while (0);
199 
200 static void
make_policy_fromfile(char * conf)201 make_policy_fromfile(char *conf)
202 {
203 	char line[_POSIX2_LINE_MAX], *cp;
204 	char *addrstr;
205 	FILE *fp;
206 	int count = 0;
207 	struct in6_addrpolicy pol0;
208 	struct policyqueue *new;
209 
210 	if ((fp = fopen(conf, "r")) == NULL)
211 		err(1, "fopen: %s", conf);
212 
213 	while(fgets(line, sizeof(line), fp)) {
214 		count++;
215 		cp = line;
216 
217 		memset(&pol0, 0, sizeof(pol0));
218 
219 		/* get prefix */
220 		SKIP_WHITE(cp, 1);
221 		if (*cp == '\n') /* empty line */
222 			continue;
223 		if (*cp == '#')
224 			continue;
225 		addrstr = cp;
226 		if (parse_prefix((const char *)addrstr, &pol0))
227 			goto bad;
228 
229 		/* get precedence value */
230 		SKIP_WORD(cp);
231 		SKIP_WHITE(cp, 0);
232 		pol0.preced = atoi(cp);
233 
234 		/* get label */
235 		SKIP_WORD(cp);
236 		SKIP_WHITE(cp, 0);
237 		pol0.label = atoi(cp);
238 
239 		/* parse succeeded.  make a control buffer entry. */
240 		if ((new = malloc(sizeof(*new))) == NULL)
241 			errx(1, "malloc failed\n");
242 		memset(new, 0, sizeof(*new));
243 		new->pc_policy = pol0;
244 		TAILQ_INSERT_TAIL(&policyhead, new, pc_entry);
245 	}
246 
247 	fclose(fp);
248 	return;
249 
250   bad:
251 	errx(1, "parse failed at line %d", count);
252 	/* NOTREACHED */
253 }
254 
255 static int
parse_prefix(const char * prefix0,struct in6_addrpolicy * pol)256 parse_prefix(const char *prefix0, struct in6_addrpolicy *pol)
257 {
258 	int e = 0, plen;
259 	char *prefix, *plenstr;
260 	struct addrinfo hints, *res;
261 
262 	if ((prefix = strdup(prefix0)) == NULL)
263 		errx(1, "strdup failed");
264 
265 	if ((plenstr = strchr(prefix, '/')) == NULL) {
266 		e = -1;
267 		goto end;
268 	}
269 	*plenstr = '\0';
270 
271 	memset(&hints, 0, sizeof(hints));
272 	hints.ai_flags = AI_NUMERICHOST;
273 	hints.ai_family = AF_INET6;
274 
275 	if ((e = getaddrinfo(prefix, NULL, &hints, &res)) != 0) {
276 		warnx("getaddrinfo failed for %s: %s", prefix,
277 		      gai_strerror(e));
278 		goto end;
279 	}
280 	memcpy(&pol->addr, res->ai_addr, res->ai_addrlen);
281 	freeaddrinfo(res);
282 	plen = atoi(plenstr + 1);
283 	if (plen < 0 || plen > 128) {
284 		warnx("invalid prefix length: %d", plen);
285 		e = -1;
286 		goto end;
287 	}
288 	plen2mask(&pol->addrmask, plen);
289 
290   end:
291 	free(prefix);
292 	return(e);
293 }
294 
295 static void
plen2mask(struct sockaddr_in6 * mask,int plen)296 plen2mask(struct sockaddr_in6 *mask, int plen)
297 {
298 	u_char *cp = (unsigned char *)&mask->sin6_addr;
299 
300 	memset(mask, 0, sizeof(*mask));
301 	mask->sin6_family = AF_INET6; /* just in case */
302 	mask->sin6_len = sizeof(*mask);
303 
304 	for(; plen >= 8; plen -= 8)
305 		*cp++ = 0xff;
306 	if (plen > 0)
307 		*cp = (0xff << (8 - plen));
308 }
309 
310 static void
set_policy(void)311 set_policy(void)
312 {
313 	struct policyqueue *ent;
314 	int s;
315 
316 	if ((s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP)) < 0)
317 		err(1, "socket(UDP)");
318 
319 	for (ent = TAILQ_FIRST(&policyhead); ent;
320 	     ent = TAILQ_NEXT(ent, pc_entry)) {
321 		if (ioctl(s, SIOCAADDRCTL_POLICY, &ent->pc_policy))
322 			warn("ioctl(SIOCAADDRCTL_POLICY)");
323 	}
324 
325 	close(s);
326 }
327 
328 static int
mask2plen(struct sockaddr_in6 * mask)329 mask2plen(struct sockaddr_in6 *mask)
330 {
331 	int masklen, final = 0;
332 	u_char *p, *lim;
333 
334 	masklen = 0;
335 	lim = (u_char *)(mask + 1);
336 	for (p = (u_char *)(&mask->sin6_addr); p < lim; p++) {
337 		if (final && *p) {
338 			goto bad;
339 		}
340 
341 		switch (*p & 0xff) {
342 		case 0xff:
343 			masklen += 8;
344 			break;
345 		case 0xfe:
346 			masklen += 7;
347 			final++;
348 			break;
349 		case 0xfc:
350 			masklen += 6;
351 			final++;
352 			break;
353 		case 0xf8:
354 			masklen += 5;
355 			final++;
356 			break;
357 		case 0xf0:
358 			masklen += 4;
359 			final++;
360 			break;
361 		case 0xe0:
362 			masklen += 3;
363 			final++;
364 			break;
365 		case 0xc0:
366 			masklen += 2;
367 			final++;
368 			break;
369 		case 0x80:
370 			masklen += 1;
371 			final++;
372 			break;
373 		case 0x00:
374 			final++;
375 			break;
376 		default:
377 			goto bad;
378 			break;
379 		}
380 	}
381 	return(masklen);
382 
383   bad:
384 	return(-1);
385 }
386 
387 static void
add_policy(char * prefix,char * prec,char * label)388 add_policy(char *prefix, char *prec, char *label)
389 {
390 	struct in6_addrpolicy p;
391 	int s;
392 
393 	memset(&p, 0, sizeof(p));
394 
395 	if (parse_prefix((const char *)prefix, &p))
396 		errx(1, "bad prefix: %s", prefix);
397 	p.preced = atoi(prec);
398 	p.label = atoi(label);
399 
400 	if ((s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP)) < 0)
401 		err(1, "socket(UDP)");
402 	if (ioctl(s, SIOCAADDRCTL_POLICY, &p))
403 		err(1, "ioctl(SIOCAADDRCTL_POLICY)");
404 
405 	close(s);
406 }
407 
408 static void
delete_policy(char * prefix)409 delete_policy(char *prefix)
410 {
411 	struct in6_addrpolicy p;
412 	int s;
413 
414 	memset(&p, 0, sizeof(p));
415 
416 	if (parse_prefix((const char *)prefix, &p))
417 		errx(1, "bad prefix: %s", prefix);
418 
419 	if ((s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP)) < 0)
420 		err(1, "socket(UDP)");
421 	if (ioctl(s, SIOCDADDRCTL_POLICY, &p))
422 		err(1, "ioctl(SIOCDADDRCTL_POLICY)");
423 
424 	close(s);
425 }
426 
427 static void
flush_policy(void)428 flush_policy(void)
429 {
430 	struct policyqueue *ent;
431 	int s;
432 
433 	if ((s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP)) < 0)
434 		err(1, "socket(UDP)");
435 
436 	for (ent = TAILQ_FIRST(&policyhead); ent;
437 	     ent = TAILQ_NEXT(ent, pc_entry)) {
438 		if (ioctl(s, SIOCDADDRCTL_POLICY, &ent->pc_policy))
439 			warn("ioctl(SIOCDADDRCTL_POLICY)");
440 	}
441 
442 	close(s);
443 }
444 
445 static void
usage(void)446 usage(void)
447 {
448 	fprintf(stderr, "usage: ip6addrctl [show]\n");
449 	fprintf(stderr, "       ip6addrctl add "
450 		"<prefix> <precedence> <label>\n");
451 	fprintf(stderr, "       ip6addrctl delete <prefix>\n");
452 	fprintf(stderr, "       ip6addrctl flush\n");
453 	fprintf(stderr, "       ip6addrctl install <configfile>\n");
454 
455 	exit(1);
456 }
457