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  * $FreeBSD: head/usr.sbin/ip6addrctl/ip6addrctl.c 326025 2017-11-20 19:49:47Z pfg $
34  */
35 
36 #include <sys/types.h>
37 #include <sys/socket.h>
38 #include <sys/queue.h>
39 #include <sys/param.h>
40 #include <sys/ioctl.h>
41 #include <sys/sysctl.h>
42 
43 #include <net/if.h>
44 
45 #include <netinet/in.h>
46 #include <netinet6/in6_var.h>
47 
48 #include <stdlib.h>
49 #include <netdb.h>
50 #include <stdio.h>
51 #include <unistd.h>
52 #include <limits.h>
53 #include <string.h>
54 #include <err.h>
55 
56 static char *configfile;
57 
58 struct policyqueue {
59 	TAILQ_ENTRY(policyqueue) pc_entry;
60 	struct in6_addrpolicy pc_policy;
61 };
62 TAILQ_HEAD(policyhead, policyqueue);
63 static struct policyhead policyhead;
64 
65 static void usage(void);
66 static void get_policy(void);
67 static void dump_policy(void);
68 static int mask2plen(struct sockaddr_in6 *);
69 static int parse_prefix(const char *, struct in6_addrpolicy *);
70 static void make_policy_fromfile(char *);
71 static void plen2mask(struct sockaddr_in6 *, int);
72 static void set_policy(void);
73 static void add_policy(char *, char *, char *);
74 static void delete_policy(char *);
75 static void flush_policy(void);
76 
77 int
78 main(int argc, char *argv[])
79 {
80 	TAILQ_INIT(&policyhead);
81 
82 	if (argc == 1 || strcasecmp(argv[1], "show") == 0) {
83 		get_policy();
84 		dump_policy();
85 	} else if (strcasecmp(argv[1], "add") == 0) {
86 		if (argc < 5)
87 			usage();
88 		add_policy(argv[2], argv[3], argv[4]);
89 	} else if (strcasecmp(argv[1], "delete") == 0) {
90 		if (argc < 3)
91 			usage();
92 		delete_policy(argv[2]);
93 	} else if (strcasecmp(argv[1], "flush") == 0) {
94 		get_policy();
95 		flush_policy();
96 	} else if (strcasecmp(argv[1], "install") == 0) {
97 		if (argc < 3)
98 			usage();
99 		configfile = argv[2];
100 		make_policy_fromfile(configfile);
101 		set_policy();
102 	} else
103 		usage();
104 
105 	exit(0);
106 }
107 
108 static void
109 get_policy(void)
110 {
111 	int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY };
112 	size_t l;
113 	struct in6_addrpolicy *buf;
114 	struct in6_addrpolicy *pol, *ep;
115 
116 	if (sysctl(mib, nitems(mib), NULL, &l, NULL, 0) < 0) {
117 		err(1, "sysctl(IPV6CTL_ADDRCTLPOLICY)");
118 		/* NOTREACHED */
119 	}
120 	if (l == 0) {
121 		printf("no source-address-selection policy is installed\n");
122 		return;
123 	}
124 	if ((buf = malloc(l)) == NULL) {
125 		errx(1, "malloc failed");
126 		/* NOTREACHED */
127 	}
128 	if (sysctl(mib, nitems(mib), buf, &l, NULL, 0) < 0) {
129 		err(1, "sysctl(IPV6CTL_ADDRCTLPOLICY)");
130 		/* NOTREACHED */
131 	}
132 
133 	ep = buf + l/sizeof(*buf);
134 	for (pol = buf; pol + 1 <= ep; pol++) {
135 		struct policyqueue *new;
136 
137 		if ((new = malloc(sizeof(*new))) == NULL)
138 			errx(1, "malloc failed\n");
139 		new->pc_policy = *pol;
140 		TAILQ_INSERT_TAIL(&policyhead, new, pc_entry);
141 	}
142 
143 	free(buf);
144 }
145 
146 static void
147 dump_policy(void)
148 {
149 	size_t addrlen;
150 	char addrbuf[NI_MAXHOST];
151 	struct in6_addrpolicy *pol;
152 	struct policyqueue *ent;
153 	int plen, first = 1;
154 
155 	for (ent = TAILQ_FIRST(&policyhead); ent;
156 	     ent = TAILQ_NEXT(ent, pc_entry)) {
157 		pol = &ent->pc_policy;
158 		if (first) {
159 			printf("%-30s %5s %5s %8s\n",
160 			       "Prefix", "Prec", "Label", "Use");
161 			first = 0;
162 		}
163 
164 		if ((getnameinfo((struct sockaddr *)&pol->addr,
165 				 sizeof(pol->addr), addrbuf, sizeof(addrbuf),
166 				 NULL, 0, NI_NUMERICHOST))) {
167 			warnx("getnameinfo for prefix address failed");
168 			continue;
169 		}
170 		if ((plen = mask2plen(&pol->addrmask)) < 0) {
171 			warnx("invalid address mask");
172 			continue;
173 		}
174 		addrlen = strlen(addrbuf);
175 		if (addrlen + sizeof("/128") < sizeof(addrbuf)) {
176 			snprintf(&addrbuf[addrlen],
177 				 sizeof(addrbuf) - addrlen - 1,
178 				 "/%d", plen);
179 			printf("%-30s", addrbuf);
180 		} else		/* XXX */
181 			printf("%s/%d", addrbuf, plen);
182 		printf(" %5d %5d %8llu\n", pol->preced, pol->label,
183 		    (unsigned long long)pol->use);
184 	}
185 }
186 
187 #define SKIP_WHITE(p, emptyok) \
188 	do { \
189 		while((*(p) == ' ' || *(p) == '\t')) \
190 			(p)++; \
191 		if ((*(p) == '\0' || (*(p) == '\n')) && !(emptyok)) \
192 			goto bad; \
193 	} while (0);
194 #define SKIP_WORD(p) \
195 	do { \
196 		while(*(p) != ' ' && *(p) != '\t') \
197 			(p)++; \
198 		if (*(p) == '\0' || *(p) == '\n') \
199 			goto bad; \
200 	} while (0);
201 
202 static void
203 make_policy_fromfile(char *conf)
204 {
205 	char line[_POSIX2_LINE_MAX], *cp;
206 	char *addrstr;
207 	FILE *fp;
208 	int count = 0;
209 	struct in6_addrpolicy pol0;
210 	struct policyqueue *new;
211 
212 	if ((fp = fopen(conf, "r")) == NULL)
213 		err(1, "fopen: %s", conf);
214 
215 	while(fgets(line, sizeof(line), fp)) {
216 		count++;
217 		cp = line;
218 
219 		memset(&pol0, 0, sizeof(pol0));
220 
221 		/* get prefix */
222 		SKIP_WHITE(cp, 1);
223 		if (*cp == '\n') /* empty line */
224 			continue;
225 		if (*cp == '#')
226 			continue;
227 		addrstr = cp;
228 		if (parse_prefix((const char *)addrstr, &pol0))
229 			goto bad;
230 
231 		/* get precedence value */
232 		SKIP_WORD(cp);
233 		SKIP_WHITE(cp, 0);
234 		pol0.preced = atoi(cp);
235 
236 		/* get label */
237 		SKIP_WORD(cp);
238 		SKIP_WHITE(cp, 0);
239 		pol0.label = atoi(cp);
240 
241 		/* parse succeeded.  make a control buffer entry. */
242 		if ((new = malloc(sizeof(*new))) == NULL)
243 			errx(1, "malloc failed\n");
244 		memset(new, 0, sizeof(*new));
245 		new->pc_policy = pol0;
246 		TAILQ_INSERT_TAIL(&policyhead, new, pc_entry);
247 	}
248 
249 	fclose(fp);
250 	return;
251 
252   bad:
253 	errx(1, "parse failed at line %d", count);
254 	/* NOTREACHED */
255 }
256 
257 static int
258 parse_prefix(const char *prefix0, struct in6_addrpolicy *pol)
259 {
260 	int e = 0, plen;
261 	char *prefix, *plenstr;
262 	struct addrinfo hints, *res;
263 
264 	if ((prefix = strdup(prefix0)) == NULL)
265 		errx(1, "strdup failed");
266 
267 	if ((plenstr = strchr(prefix, '/')) == NULL) {
268 		e = -1;
269 		goto end;
270 	}
271 	*plenstr = '\0';
272 
273 	memset(&hints, 0, sizeof(hints));
274 	hints.ai_flags = AI_NUMERICHOST;
275 	hints.ai_family = AF_INET6;
276 
277 	if ((e = getaddrinfo(prefix, NULL, &hints, &res)) != 0) {
278 		warnx("getaddrinfo failed for %s: %s", prefix,
279 		      gai_strerror(e));
280 		goto end;
281 	}
282 	memcpy(&pol->addr, res->ai_addr, res->ai_addrlen);
283 	freeaddrinfo(res);
284 	plen = atoi(plenstr + 1);
285 	if (plen < 0 || plen > 128) {
286 		warnx("invalid prefix length: %d", plen);
287 		e = -1;
288 		goto end;
289 	}
290 	plen2mask(&pol->addrmask, plen);
291 
292   end:
293 	free(prefix);
294 	return(e);
295 }
296 
297 static void
298 plen2mask(struct sockaddr_in6 *mask, int plen)
299 {
300 	u_char *cp = (unsigned char *)&mask->sin6_addr;
301 
302 	memset(mask, 0, sizeof(*mask));
303 	mask->sin6_family = AF_INET6; /* just in case */
304 	mask->sin6_len = sizeof(*mask);
305 
306 	for(; plen >= 8; plen -= 8)
307 		*cp++ = 0xff;
308 	if (plen > 0)
309 		*cp = (0xff << (8 - plen));
310 }
311 
312 static void
313 set_policy(void)
314 {
315 	struct policyqueue *ent;
316 	int s;
317 
318 	if ((s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP)) < 0)
319 		err(1, "socket(UDP)");
320 
321 	for (ent = TAILQ_FIRST(&policyhead); ent;
322 	     ent = TAILQ_NEXT(ent, pc_entry)) {
323 		if (ioctl(s, SIOCAADDRCTL_POLICY, &ent->pc_policy))
324 			warn("ioctl(SIOCAADDRCTL_POLICY)");
325 	}
326 
327 	close(s);
328 }
329 
330 static int
331 mask2plen(struct sockaddr_in6 *mask)
332 {
333 	int masklen, final = 0;
334 	u_char *p, *lim;
335 
336 	masklen = 0;
337 	lim = (u_char *)(mask + 1);
338 	for (p = (u_char *)(&mask->sin6_addr); p < lim; p++) {
339 		if (final && *p) {
340 			goto bad;
341 		}
342 
343 		switch (*p & 0xff) {
344 		case 0xff:
345 			masklen += 8;
346 			break;
347 		case 0xfe:
348 			masklen += 7;
349 			final++;
350 			break;
351 		case 0xfc:
352 			masklen += 6;
353 			final++;
354 			break;
355 		case 0xf8:
356 			masklen += 5;
357 			final++;
358 			break;
359 		case 0xf0:
360 			masklen += 4;
361 			final++;
362 			break;
363 		case 0xe0:
364 			masklen += 3;
365 			final++;
366 			break;
367 		case 0xc0:
368 			masklen += 2;
369 			final++;
370 			break;
371 		case 0x80:
372 			masklen += 1;
373 			final++;
374 			break;
375 		case 0x00:
376 			final++;
377 			break;
378 		default:
379 			goto bad;
380 			break;
381 		}
382 	}
383 	return(masklen);
384 
385   bad:
386 	return(-1);
387 }
388 
389 static void
390 add_policy(char *prefix, char *prec, char *label)
391 {
392 	struct in6_addrpolicy p;
393 	int s;
394 
395 	memset(&p, 0, sizeof(p));
396 
397 	if (parse_prefix((const char *)prefix, &p))
398 		errx(1, "bad prefix: %s", prefix);
399 	p.preced = atoi(prec);
400 	p.label = atoi(label);
401 
402 	if ((s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP)) < 0)
403 		err(1, "socket(UDP)");
404 	if (ioctl(s, SIOCAADDRCTL_POLICY, &p))
405 		err(1, "ioctl(SIOCAADDRCTL_POLICY)");
406 
407 	close(s);
408 }
409 
410 static void
411 delete_policy(char *prefix)
412 {
413 	struct in6_addrpolicy p;
414 	int s;
415 
416 	memset(&p, 0, sizeof(p));
417 
418 	if (parse_prefix((const char *)prefix, &p))
419 		errx(1, "bad prefix: %s", prefix);
420 
421 	if ((s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP)) < 0)
422 		err(1, "socket(UDP)");
423 	if (ioctl(s, SIOCDADDRCTL_POLICY, &p))
424 		err(1, "ioctl(SIOCDADDRCTL_POLICY)");
425 
426 	close(s);
427 }
428 
429 static void
430 flush_policy(void)
431 {
432 	struct policyqueue *ent;
433 	int s;
434 
435 	if ((s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP)) < 0)
436 		err(1, "socket(UDP)");
437 
438 	for (ent = TAILQ_FIRST(&policyhead); ent;
439 	     ent = TAILQ_NEXT(ent, pc_entry)) {
440 		if (ioctl(s, SIOCDADDRCTL_POLICY, &ent->pc_policy))
441 			warn("ioctl(SIOCDADDRCTL_POLICY)");
442 	}
443 
444 	close(s);
445 }
446 
447 static void
448 usage(void)
449 {
450 	fprintf(stderr, "usage: ip6addrctl [show]\n");
451 	fprintf(stderr, "       ip6addrctl add "
452 		"<prefix> <precedence> <label>\n");
453 	fprintf(stderr, "       ip6addrctl delete <prefix>\n");
454 	fprintf(stderr, "       ip6addrctl flush\n");
455 	fprintf(stderr, "       ip6addrctl install <configfile>\n");
456 
457 	exit(1);
458 }
459