xref: /freebsd/lib/libjail/jail.c (revision 830940567b49bb0c08dfaed40418999e76616909)
1 /*-
2  * Copyright (c) 2009 James Gritton.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/types.h>
32 #include <sys/jail.h>
33 #include <sys/socket.h>
34 #include <sys/sysctl.h>
35 
36 #include <arpa/inet.h>
37 #include <netinet/in.h>
38 
39 #include <errno.h>
40 #include <inttypes.h>
41 #include <stdio.h>
42 #include <stdarg.h>
43 #include <stdlib.h>
44 #include <string.h>
45 
46 #include "jail.h"
47 
48 #define	SJPARAM		"security.jail.param"
49 
50 #define JPS_IN_ADDR	1
51 #define JPS_IN6_ADDR	2
52 
53 #define ARRAY_SANITY	5
54 #define ARRAY_SLOP	5
55 
56 
57 static int jailparam_import_enum(const char **values, int nvalues,
58     const char *valstr, size_t valsize, int *value);
59 static int jailparam_vlist(struct jailparam **jpp, va_list ap);
60 static int jailparam_type(struct jailparam *jp);
61 static char *noname(const char *name);
62 static char *nononame(const char *name);
63 
64 char jail_errmsg[JAIL_ERRMSGLEN];
65 
66 static const char *bool_values[] = { "false", "true" };
67 static const char *jailsys_values[] = { "disable", "new", "inherit" };
68 
69 
70 /*
71  * Import a null-terminated parameter list and set a jail with the flags
72  * and parameters.
73  */
74 int
75 jail_setv(int flags, ...)
76 {
77 	va_list ap;
78 	struct jailparam *jp;
79 	int njp;
80 
81 	va_start(ap, flags);
82 	njp = jailparam_vlist(&jp, ap);
83 	va_end(ap);
84 	if (njp < 0)
85 		return (njp);
86 	return (jailparam_set(jp, njp, flags));
87 }
88 
89 /*
90  * Read a null-terminated parameter list, get the referenced jail, and export
91  * the parameters to the list.
92  */
93 int
94 jail_getv(int flags, ...)
95 {
96 	va_list ap, tap;
97 	struct jailparam *jp;
98 	char *valarg;
99 	const char *value;
100 	int njp, i, jid, namekey, zero;
101 
102 	va_start(ap, flags);
103 	va_copy(tap, ap);
104 	njp = jailparam_vlist(&jp, tap);
105 	va_end(tap);
106 	if (njp < 0)
107 		return (njp);
108 	/*
109 	 * See if the name is the search key.  If so, we don't want to write
110 	 * it back in case it's a read-only string.
111 	 */
112 	namekey = 1;
113 	zero = 0;
114 	for (i = 0; i < njp; i++) {
115 		if (!strcmp(jp->jp_name, "lastjid") ||
116 		    (!strcmp(jp->jp_name, "jid") &&
117 		     memcmp(jp->jp_value, &zero, sizeof(zero))))
118 			namekey = 0;
119 	}
120 	jid = jailparam_get(jp, njp, flags);
121 	if (jid < 0) {
122 		va_end(ap);
123 		return (-1);
124 	}
125 	for (i = 0; i < njp; i++) {
126 		(void)va_arg(ap, char *);
127 		value = jailparam_export(jp + i);
128 		if (value == NULL) {
129 			va_end(ap);
130 			return (-1);
131 		}
132 		valarg = va_arg(ap, char *);
133 		if (!namekey || strcmp(jp[i].jp_name, "name"))
134 			/* It's up to the caller to ensure there's room. */
135 			strcpy(valarg, value);
136 	}
137 	va_end(ap);
138 	return (jid);
139 }
140 
141 /*
142  * Return a list of all known parameters.
143  */
144 int
145 jailparam_all(struct jailparam **jpp)
146 {
147 	struct jailparam *jp;
148 	size_t mlen1, mlen2, buflen;
149 	int njp, nlist;
150 	int mib1[CTL_MAXNAME], mib2[CTL_MAXNAME - 2];
151 	char buf[MAXPATHLEN];
152 
153 	njp = 0;
154 	nlist = 32;
155 	jp = malloc(nlist * sizeof(*jp));
156 	if (jp == NULL) {
157 		strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
158 		return (-1);
159 	}
160 	mib1[0] = 0;
161 	mib1[1] = 2;
162 	mlen1 = CTL_MAXNAME - 2;
163 	if (sysctlnametomib(SJPARAM, mib1 + 2, &mlen1) < 0) {
164 		snprintf(jail_errmsg, JAIL_ERRMSGLEN,
165 		    "sysctlnametomib(" SJPARAM "): %s", strerror(errno));
166 		goto error;
167 	}
168 	for (;; njp++) {
169 		/* Get the next parameter. */
170 		mlen2 = sizeof(mib2);
171 		if (sysctl(mib1, mlen1 + 2, mib2, &mlen2, NULL, 0) < 0) {
172 			snprintf(jail_errmsg, JAIL_ERRMSGLEN,
173 			    "sysctl(0.2): %s", strerror(errno));
174 			goto error;
175 		}
176 		if (mib2[0] != mib1[2] || mib2[1] != mib1[3] ||
177 		    mib2[2] != mib1[4])
178 			break;
179 		/* Convert it to an ascii name. */
180 		memcpy(mib1 + 2, mib2, mlen2);
181 		mlen1 = mlen2 / sizeof(int);
182 		mib1[1] = 1;
183 		buflen = sizeof(buf);
184 		if (sysctl(mib1, mlen1 + 2, buf, &buflen, NULL, 0) < 0) {
185 			snprintf(jail_errmsg, JAIL_ERRMSGLEN,
186 			    "sysctl(0.1): %s", strerror(errno));
187 			goto error;
188 		}
189 		if (buf[buflen - 2] == '.')
190 			buf[buflen - 2] = '\0';
191 		/* Add the parameter to the list */
192 		if (njp >= nlist) {
193 			nlist *= 2;
194 			jp = realloc(jp, nlist * sizeof(jp));
195 			if (jp == NULL) {
196 				jailparam_free(jp, njp);
197 				return (-1);
198 			}
199 		}
200 		if (jailparam_init(jp + njp, buf + sizeof(SJPARAM)) < 0)
201 			goto error;
202 		if (jailparam_type(jp + njp) < 0) {
203 			njp++;
204 			goto error;
205 		}
206 		mib1[1] = 2;
207 	}
208 	jp = realloc(jp, njp * sizeof(*jp));
209 	*jpp = jp;
210 	return (njp);
211 
212  error:
213 	jailparam_free(jp, njp);
214 	free(jp);
215 	return (-1);
216 }
217 
218 /*
219  * Clear a jail parameter and copy in its name.
220  */
221 int
222 jailparam_init(struct jailparam *jp, const char *name)
223 {
224 
225 	memset(jp, 0, sizeof(*jp));
226 	jp->jp_name = strdup(name);
227 	if (jp->jp_name == NULL) {
228 		strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
229 		return (-1);
230 	}
231 	return (0);
232 }
233 
234 /*
235  * Put a name and value into a jail parameter element, converting the value
236  * to internal form.
237  */
238 int
239 jailparam_import(struct jailparam *jp, const char *value)
240 {
241 	char *p, *ep, *tvalue;
242 	const char *avalue;
243 	int i, nval, fw;
244 
245 	if (!jp->jp_ctltype && jailparam_type(jp) < 0)
246 		return (-1);
247 	if (value == NULL)
248 		return (0);
249 	if ((jp->jp_ctltype & CTLTYPE) == CTLTYPE_STRING) {
250 		jp->jp_value = strdup(value);
251 		if (jp->jp_value == NULL) {
252 			strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
253 			return (-1);
254 		}
255 		return (0);
256 	}
257 	nval = 1;
258 	if (jp->jp_elemlen) {
259 		if (value[0] == '\0' || (value[0] == '-' && value[1] == '\0')) {
260 			jp->jp_value = strdup("");
261 			if (jp->jp_value == NULL) {
262 				strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
263 				return (-1);
264 			}
265 			jp->jp_valuelen = 0;
266 			return (0);
267 		}
268 		for (p = strchr(value, ','); p; p = strchr(p + 1, ','))
269 			nval++;
270 		jp->jp_valuelen = jp->jp_elemlen * nval;
271 	}
272 	jp->jp_value = malloc(jp->jp_valuelen);
273 	if (jp->jp_value == NULL) {
274 		strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
275 		return (-1);
276 	}
277 	avalue = value;
278 	for (i = 0; i < nval; i++) {
279 		fw = nval == 1 ? strlen(avalue) : strcspn(avalue, ",");
280 		switch (jp->jp_ctltype & CTLTYPE) {
281 		case CTLTYPE_INT:
282 			if (jp->jp_flags & (JP_BOOL | JP_NOBOOL)) {
283 				if (!jailparam_import_enum(bool_values, 2,
284 				    avalue, fw, &((int *)jp->jp_value)[i])) {
285 					snprintf(jail_errmsg,
286 					    JAIL_ERRMSGLEN, "%s: "
287 					    "unknown boolean value \"%.*s\"",
288 					    jp->jp_name, fw, avalue);
289 					errno = EINVAL;
290 					goto error;
291 				}
292 				break;
293 			}
294 			if (jp->jp_flags & JP_JAILSYS) {
295 				/*
296 				 * Allow setting a jailsys parameter to "new"
297 				 * in a booleanesque fashion.
298 				 */
299 				if (value[0] == '\0')
300 					((int *)jp->jp_value)[i] = JAIL_SYS_NEW;
301 				else if (!jailparam_import_enum(jailsys_values,
302 				    sizeof(jailsys_values) /
303 				    sizeof(jailsys_values[0]), avalue, fw,
304 				    &((int *)jp->jp_value)[i])) {
305 					snprintf(jail_errmsg,
306 					    JAIL_ERRMSGLEN, "%s: "
307 					    "unknown jailsys value \"%.*s\"",
308 					    jp->jp_name, fw, avalue);
309 					errno = EINVAL;
310 					goto error;
311 				}
312 				break;
313 			}
314 			((int *)jp->jp_value)[i] = strtol(avalue, &ep, 10);
315 		integer_test:
316 			if (ep != avalue + fw) {
317 				snprintf(jail_errmsg, JAIL_ERRMSGLEN,
318 				    "%s: non-integer value \"%.*s\"",
319 				    jp->jp_name, fw, avalue);
320 				errno = EINVAL;
321 				goto error;
322 			}
323 			break;
324 		case CTLTYPE_UINT:
325 			((unsigned *)jp->jp_value)[i] =
326 			    strtoul(avalue, &ep, 10);
327 			goto integer_test;
328 		case CTLTYPE_LONG:
329 			((long *)jp->jp_value)[i] = strtol(avalue, &ep, 10);
330 			goto integer_test;
331 		case CTLTYPE_ULONG:
332 			((unsigned long *)jp->jp_value)[i] =
333 			    strtoul(avalue, &ep, 10);
334 			goto integer_test;
335 		case CTLTYPE_QUAD:
336 			((int64_t *)jp->jp_value)[i] =
337 			    strtoimax(avalue, &ep, 10);
338 			goto integer_test;
339 		case CTLTYPE_STRUCT:
340 			tvalue = alloca(fw + 1);
341 			strlcpy(tvalue, avalue, fw + 1);
342 			switch (jp->jp_structtype) {
343 			case JPS_IN_ADDR:
344 				if (inet_pton(AF_INET, tvalue,
345 				    &((struct in_addr *)jp->jp_value)[i]) != 1)
346 				{
347 					snprintf(jail_errmsg,
348 					    JAIL_ERRMSGLEN,
349 					    "%s: not an IPv4 address: %s",
350 					    jp->jp_name, tvalue);
351 					errno = EINVAL;
352 					goto error;
353 				}
354 				break;
355 			case JPS_IN6_ADDR:
356 				if (inet_pton(AF_INET6, tvalue,
357 				    &((struct in6_addr *)jp->jp_value)[i]) != 1)
358 				{
359 					snprintf(jail_errmsg,
360 					    JAIL_ERRMSGLEN,
361 					    "%s: not an IPv6 address: %s",
362 					    jp->jp_name, tvalue);
363 					errno = EINVAL;
364 					goto error;
365 				}
366 				break;
367 			default:
368 				goto unknown_type;
369 			}
370 			break;
371 		default:
372 		unknown_type:
373 			snprintf(jail_errmsg, JAIL_ERRMSGLEN,
374 			    "unknown type for %s", jp->jp_name);
375 			errno = ENOENT;
376 			goto error;
377 		}
378 		avalue += fw + 1;
379 	}
380 	return (0);
381 
382  error:
383 	free(jp->jp_value);
384 	jp->jp_value = NULL;
385 	return (-1);
386 }
387 
388 static int
389 jailparam_import_enum(const char **values, int nvalues, const char *valstr,
390     size_t valsize, int *value)
391 {
392 	char *ep;
393 	int i;
394 
395 	for (i = 0; i < nvalues; i++)
396 		if (valsize == strlen(values[i]) &&
397 		    !strncasecmp(valstr, values[i], valsize)) {
398 			*value = i;
399 			return 1;
400 		}
401 	*value = strtol(valstr, &ep, 10);
402 	return (ep == valstr + valsize);
403 }
404 
405 /*
406  * Put a name and value into a jail parameter element, copying the value
407  * but not altering it.
408  */
409 int
410 jailparam_import_raw(struct jailparam *jp, void *value, size_t valuelen)
411 {
412 
413 	jp->jp_value = value;
414 	jp->jp_valuelen = valuelen;
415 	jp->jp_flags |= JP_RAWVALUE;
416 	return (0);
417 }
418 
419 /*
420  * Run the jail_set and jail_get system calls on a parameter list.
421  */
422 int
423 jailparam_set(struct jailparam *jp, unsigned njp, int flags)
424 {
425 	struct iovec *jiov;
426 	char *nname;
427 	int i, jid, bool0;
428 	unsigned j;
429 
430 	jiov = alloca(sizeof(struct iovec) * 2 * (njp + 1));
431 	bool0 = 0;
432 	for (i = j = 0; j < njp; j++) {
433 		jiov[i].iov_base = jp[j].jp_name;
434 		jiov[i].iov_len = strlen(jp[j].jp_name) + 1;
435 		i++;
436 		if (jp[j].jp_flags & (JP_BOOL | JP_NOBOOL)) {
437 			/*
438 			 * Set booleans without values.  If one has a value of
439 			 * zero, change it to (or from) its "no" counterpart.
440 			 */
441 			jiov[i].iov_base = NULL;
442 			jiov[i].iov_len = 0;
443 			if (jp[j].jp_value != NULL &&
444 			    jp[j].jp_valuelen == sizeof(int) &&
445 			    !*(int *)jp[j].jp_value) {
446 				bool0 = 1;
447 				nname = jp[j].jp_flags & JP_BOOL
448 				    ? noname(jp[j].jp_name)
449 				    : nononame(jp[j].jp_name);
450 				if (nname == NULL) {
451 					njp = j;
452 					jid = -1;
453 					goto done;
454 				}
455 				jiov[i - 1].iov_base = nname;
456 				jiov[i - 1].iov_len = strlen(nname) + 1;
457 
458 			}
459 		} else {
460 			/*
461 			 * Try to fill in missing values with an empty string.
462 			 */
463 			if (jp[j].jp_value == NULL && jp[j].jp_valuelen > 0 &&
464 			    jailparam_import(jp + j, "") < 0) {
465 				njp = j;
466 				jid = -1;
467 				goto done;
468 			}
469 			jiov[i].iov_base = jp[j].jp_value;
470 			jiov[i].iov_len =
471 			    (jp[j].jp_ctltype & CTLTYPE) == CTLTYPE_STRING
472 			    ? strlen(jp[j].jp_value) + 1
473 			    : jp[j].jp_valuelen;
474 		}
475 		i++;
476 	}
477 	*(const void **)&jiov[i].iov_base = "errmsg";
478 	jiov[i].iov_len = sizeof("errmsg");
479 	i++;
480 	jiov[i].iov_base = jail_errmsg;
481 	jiov[i].iov_len = JAIL_ERRMSGLEN;
482 	i++;
483 	jail_errmsg[0] = 0;
484 	jid = jail_set(jiov, i, flags);
485 	if (jid < 0 && !jail_errmsg[0])
486 		snprintf(jail_errmsg, sizeof(jail_errmsg), "jail_set: %s",
487 		    strerror(errno));
488  done:
489 	if (bool0)
490 		for (j = 0; j < njp; j++)
491 			if ((jp[j].jp_flags & (JP_BOOL | JP_NOBOOL)) &&
492 			    jp[j].jp_value != NULL &&
493 			    jp[j].jp_valuelen == sizeof(int) &&
494 			    !*(int *)jp[j].jp_value)
495 				free(jiov[j * 2].iov_base);
496 	return (jid);
497 }
498 
499 int
500 jailparam_get(struct jailparam *jp, unsigned njp, int flags)
501 {
502 	struct iovec *jiov;
503 	struct jailparam *jp_lastjid, *jp_jid, *jp_name, *jp_key;
504 	int i, ai, ki, jid, arrays, sanity;
505 	unsigned j;
506 
507 	/*
508 	 * Get the types for all parameters.
509 	 * Find the key and any array parameters.
510 	 */
511 	jiov = alloca(sizeof(struct iovec) * 2 * (njp + 1));
512 	jp_lastjid = jp_jid = jp_name = NULL;
513 	arrays = 0;
514 	for (ai = j = 0; j < njp; j++) {
515 		if (!jp[j].jp_ctltype && jailparam_type(jp + j) < 0)
516 			return (-1);
517 		if (!strcmp(jp[j].jp_name, "lastjid"))
518 			jp_lastjid = jp + j;
519 		else if (!strcmp(jp[j].jp_name, "jid"))
520 			jp_jid = jp + j;
521 		else if (!strcmp(jp[j].jp_name, "name"))
522 			jp_name = jp + j;
523 		else if (jp[j].jp_elemlen && !(jp[j].jp_flags & JP_RAWVALUE)) {
524 			arrays = 1;
525 			jiov[ai].iov_base = jp[j].jp_name;
526 			jiov[ai].iov_len = strlen(jp[j].jp_name) + 1;
527 			ai++;
528 			jiov[ai].iov_base = NULL;
529 			jiov[ai].iov_len = 0;
530 			ai++;
531 		}
532 	}
533 	jp_key = jp_lastjid ? jp_lastjid :
534 	    jp_jid && jp_jid->jp_valuelen == sizeof(int) &&
535 	    *(int *)jp_jid->jp_value ? jp_jid : jp_name;
536 	if (jp_key == NULL || jp_key->jp_value == NULL) {
537 		strlcpy(jail_errmsg, "no jail specified", JAIL_ERRMSGLEN);
538 		errno = ENOENT;
539 		return (-1);
540 	}
541 	ki = ai;
542 	jiov[ki].iov_base = jp_key->jp_name;
543 	jiov[ki].iov_len = strlen(jp_key->jp_name) + 1;
544 	ki++;
545 	jiov[ki].iov_base = jp_key->jp_value;
546 	jiov[ki].iov_len = (jp_key->jp_ctltype & CTLTYPE) == CTLTYPE_STRING
547 	    ? strlen(jp_key->jp_value) + 1 : jp_key->jp_valuelen;
548 	ki++;
549 	*(const void **)&jiov[ki].iov_base = "errmsg";
550 	jiov[ki].iov_len = sizeof("errmsg");
551 	ki++;
552 	jiov[ki].iov_base = jail_errmsg;
553 	jiov[ki].iov_len = JAIL_ERRMSGLEN;
554 	ki++;
555 	jail_errmsg[0] = 0;
556 	if (arrays && jail_get(jiov, ki, flags) < 0) {
557 		if (!jail_errmsg[0])
558 			snprintf(jail_errmsg, sizeof(jail_errmsg),
559 			    "jail_get: %s", strerror(errno));
560 		return (-1);
561 	}
562 	/* Allocate storage for all parameters. */
563 	for (ai = j = 0, i = ki; j < njp; j++) {
564 		if (jp[j].jp_elemlen && !(jp[j].jp_flags & JP_RAWVALUE)) {
565 			ai++;
566 			jiov[ai].iov_len += jp[j].jp_elemlen * ARRAY_SLOP;
567 			if (jp[j].jp_valuelen >= jiov[ai].iov_len)
568 				jiov[ai].iov_len = jp[j].jp_valuelen;
569 			else {
570 				jp[j].jp_valuelen = jiov[ai].iov_len;
571 				if (jp[j].jp_value != NULL)
572 					free(jp[j].jp_value);
573 				jp[j].jp_value = malloc(jp[j].jp_valuelen);
574 				if (jp[j].jp_value == NULL) {
575 					strerror_r(errno, jail_errmsg,
576 					    JAIL_ERRMSGLEN);
577 					return (-1);
578 				}
579 			}
580 			jiov[ai].iov_base = jp[j].jp_value;
581 			memset(jiov[ai].iov_base, 0, jiov[ai].iov_len);
582 			ai++;
583 		} else if (jp + j != jp_key) {
584 			jiov[i].iov_base = jp[j].jp_name;
585 			jiov[i].iov_len = strlen(jp[j].jp_name) + 1;
586 			i++;
587 			if (jp[j].jp_value == NULL &&
588 			    !(jp[j].jp_flags & JP_RAWVALUE)) {
589 				jp[j].jp_value = malloc(jp[j].jp_valuelen);
590 				if (jp[j].jp_value == NULL) {
591 					strerror_r(errno, jail_errmsg,
592 					    JAIL_ERRMSGLEN);
593 					return (-1);
594 				}
595 			}
596 			jiov[i].iov_base = jp[j].jp_value;
597 			jiov[i].iov_len = jp[j].jp_valuelen;
598 			memset(jiov[i].iov_base, 0, jiov[i].iov_len);
599 			i++;
600 		}
601 	}
602 	/*
603 	 * Get the prison.  If there are array elements, retry a few times
604 	 * in case their sizes changed from under us.
605 	 */
606 	for (sanity = 0;; sanity++) {
607 		jid = jail_get(jiov, i, flags);
608 		if (jid >= 0 || !arrays || sanity == ARRAY_SANITY ||
609 		    errno != EINVAL || jail_errmsg[0])
610 			break;
611 		for (ai = j = 0; j < njp; j++) {
612 			if (jp[j].jp_elemlen &&
613 			    !(jp[j].jp_flags & JP_RAWVALUE)) {
614 				ai++;
615 				jiov[ai].iov_base = NULL;
616 				jiov[ai].iov_len = 0;
617 				ai++;
618 			}
619 		}
620 		if (jail_get(jiov, ki, flags) < 0)
621 			break;
622 		for (ai = j = 0; j < njp; j++) {
623 			if (jp[j].jp_elemlen &&
624 			    !(jp[j].jp_flags & JP_RAWVALUE)) {
625 				ai++;
626 				jiov[ai].iov_len +=
627 				    jp[j].jp_elemlen * ARRAY_SLOP;
628 				if (jp[j].jp_valuelen >= jiov[ai].iov_len)
629 					jiov[ai].iov_len = jp[j].jp_valuelen;
630 				else {
631 					jp[j].jp_valuelen = jiov[ai].iov_len;
632 					if (jp[j].jp_value != NULL)
633 						free(jp[j].jp_value);
634 					jp[j].jp_value =
635 					    malloc(jiov[ai].iov_len);
636 					if (jp[j].jp_value == NULL) {
637 						strerror_r(errno, jail_errmsg,
638 						    JAIL_ERRMSGLEN);
639 						return (-1);
640 					}
641 				}
642 				jiov[ai].iov_base = jp[j].jp_value;
643 				memset(jiov[ai].iov_base, 0, jiov[ai].iov_len);
644 				ai++;
645 			}
646 		}
647 	}
648 	if (jid < 0 && !jail_errmsg[0])
649 		snprintf(jail_errmsg, sizeof(jail_errmsg),
650 		    "jail_get: %s", strerror(errno));
651 	for (ai = j = 0, i = ki; j < njp; j++) {
652 		if (jp[j].jp_elemlen && !(jp[j].jp_flags & JP_RAWVALUE)) {
653 			ai++;
654 			jp[j].jp_valuelen = jiov[ai].iov_len;
655 			ai++;
656 		} else if (jp + j != jp_key) {
657 			i++;
658 			jp[j].jp_valuelen = jiov[i].iov_len;
659 			i++;
660 		}
661 	}
662 	return (jid);
663 }
664 
665 /*
666  * Convert a jail parameter's value to external form.
667  */
668 char *
669 jailparam_export(struct jailparam *jp)
670 {
671 	char *value, *tvalue, **values;
672 	size_t valuelen;
673 	int i, nval, ival;
674 	char valbuf[INET6_ADDRSTRLEN];
675 
676 	if (!jp->jp_ctltype && jailparam_type(jp) < 0)
677 		return (NULL);
678 	if ((jp->jp_ctltype & CTLTYPE) == CTLTYPE_STRING) {
679 		value = strdup(jp->jp_value);
680 		if (value == NULL)
681 			strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
682 		return (value);
683 	}
684 	nval = jp->jp_elemlen ? jp->jp_valuelen / jp->jp_elemlen : 1;
685 	if (nval == 0) {
686 		value = strdup("");
687 		if (value == NULL)
688 			strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
689 		return (value);
690 	}
691 	values = alloca(nval * sizeof(char *));
692 	valuelen = 0;
693 	for (i = 0; i < nval; i++) {
694 		switch (jp->jp_ctltype & CTLTYPE) {
695 		case CTLTYPE_INT:
696 			ival = ((int *)jp->jp_value)[i];
697 			if ((jp->jp_flags & (JP_BOOL | JP_NOBOOL)) &&
698 			    (unsigned)ival < 2) {
699 				strlcpy(valbuf, bool_values[ival],
700 				    sizeof(valbuf));
701 				break;
702 			}
703 			if ((jp->jp_flags & JP_JAILSYS) &&
704 			    (unsigned)ival < sizeof(jailsys_values) /
705 			    sizeof(jailsys_values[0])) {
706 				strlcpy(valbuf, jailsys_values[ival],
707 				    sizeof(valbuf));
708 				break;
709 			}
710 			snprintf(valbuf, sizeof(valbuf), "%d", ival);
711 			break;
712 		case CTLTYPE_UINT:
713 			snprintf(valbuf, sizeof(valbuf), "%u",
714 			    ((unsigned *)jp->jp_value)[i]);
715 			break;
716 		case CTLTYPE_LONG:
717 			snprintf(valbuf, sizeof(valbuf), "%ld",
718 			    ((long *)jp->jp_value)[i]);
719 			break;
720 		case CTLTYPE_ULONG:
721 			snprintf(valbuf, sizeof(valbuf), "%lu",
722 			    ((unsigned long *)jp->jp_value)[i]);
723 			break;
724 		case CTLTYPE_QUAD:
725 			snprintf(valbuf, sizeof(valbuf), "%jd",
726 			    (intmax_t)((int64_t *)jp->jp_value)[i]);
727 			break;
728 		case CTLTYPE_STRUCT:
729 			switch (jp->jp_structtype) {
730 			case JPS_IN_ADDR:
731 				if (inet_ntop(AF_INET,
732 				    &((struct in_addr *)jp->jp_value)[i],
733 				    valbuf, sizeof(valbuf)) == NULL) {
734 					strerror_r(errno, jail_errmsg,
735 					    JAIL_ERRMSGLEN);
736 
737 					return (NULL);
738 				}
739 				break;
740 			case JPS_IN6_ADDR:
741 				if (inet_ntop(AF_INET6,
742 				    &((struct in6_addr *)jp->jp_value)[i],
743 				    valbuf, sizeof(valbuf)) == NULL) {
744 					strerror_r(errno, jail_errmsg,
745 					    JAIL_ERRMSGLEN);
746 
747 					return (NULL);
748 				}
749 				break;
750 			default:
751 				goto unknown_type;
752 			}
753 			break;
754 		default:
755 		unknown_type:
756 			snprintf(jail_errmsg, JAIL_ERRMSGLEN,
757 			    "unknown type for %s", jp->jp_name);
758 			errno = ENOENT;
759 			return (NULL);
760 		}
761 		valuelen += strlen(valbuf) + 1;
762 		values[i] = alloca(valuelen);
763 		strcpy(values[i], valbuf);
764 	}
765 	value = malloc(valuelen + 1);
766 	if (value == NULL)
767 		strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
768 	else {
769 		tvalue = value;
770 		for (i = 0; i < nval; i++) {
771 			strcpy(tvalue, values[i]);
772 			if (i < nval - 1) {
773 				tvalue += strlen(values[i]);
774 				*tvalue++ = ',';
775 			}
776 		}
777 	}
778 	return (value);
779 }
780 
781 /*
782  * Free the contents of a jail parameter list (but not thst list itself).
783  */
784 void
785 jailparam_free(struct jailparam *jp, unsigned njp)
786 {
787 	unsigned j;
788 
789 	for (j = 0; j < njp; j++) {
790 		free(jp[j].jp_name);
791 		if (!(jp[j].jp_flags & JP_RAWVALUE))
792 			free(jp[j].jp_value);
793 	}
794 }
795 
796 /*
797  * Create and import an array of jail parameters, given a list of name and
798  * value strings, terminated by a null name.
799  */
800 static int
801 jailparam_vlist(struct jailparam **jpp, va_list ap)
802 {
803 	va_list tap;
804 	struct jailparam *jp;
805 	char *name, *value;
806 	int njp;
807 
808 	va_copy(tap, ap);
809 	for (njp = 0; va_arg(tap, char *) != NULL; njp++)
810 		(void)va_arg(tap, char *);
811 	va_end(tap);
812 	jp = calloc(njp, sizeof(struct jailparam));
813 	if (jp == NULL) {
814 		strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
815 		return (-1);
816 	}
817 
818 	for (njp = 0; (name = va_arg(ap, char *)) != NULL; njp++) {
819 		value = va_arg(ap, char *);
820 		if (jailparam_init(jp + njp, name) < 0 ||
821 		    jailparam_import(jp + njp, value) < 0) {
822 			jailparam_free(jp, njp);
823 			free(jp);
824 			return (-1);
825 		}
826 	}
827 	*jpp = jp;
828 	return (njp);
829 }
830 
831 /*
832  * Find a parameter's type and size from its MIB.
833  */
834 static int
835 jailparam_type(struct jailparam *jp)
836 {
837 	char *p, *nname;
838 	size_t miblen, desclen;
839 	int isarray;
840 	struct {
841 	    int i;
842 	    char s[MAXPATHLEN];
843 	} desc;
844 	int mib[CTL_MAXNAME];
845 
846 	/* The "lastjid" parameter isn't real. */
847 	if (!strcmp(jp->jp_name, "lastjid")) {
848 		jp->jp_valuelen = sizeof(int);
849 		jp->jp_ctltype = CTLTYPE_INT | CTLFLAG_WR;
850 		return (0);
851 	}
852 
853 	/* Find the sysctl that describes the parameter. */
854 	mib[0] = 0;
855 	mib[1] = 3;
856 	snprintf(desc.s, sizeof(desc.s), SJPARAM ".%s", jp->jp_name);
857 	miblen = sizeof(mib) - 2 * sizeof(int);
858 	if (sysctl(mib, 2, mib + 2, &miblen, desc.s, strlen(desc.s)) < 0) {
859 		if (errno != ENOENT) {
860 			snprintf(jail_errmsg, JAIL_ERRMSGLEN,
861 			    "sysctl(0.3.%s): %s", jp->jp_name, strerror(errno));
862 			return (-1);
863 		}
864 		/*
865 		 * The parameter probably doesn't exist.  But it might be
866 		 * the "no" counterpart to a boolean.
867 		 */
868 		nname = nononame(jp->jp_name);
869 		if (nname != NULL) {
870 			snprintf(desc.s, sizeof(desc.s), SJPARAM ".%s", nname);
871 			free(nname);
872 			miblen = sizeof(mib) - 2 * sizeof(int);
873 			if (sysctl(mib, 2, mib + 2, &miblen, desc.s,
874 			    strlen(desc.s)) >= 0) {
875 				mib[1] = 4;
876 				desclen = sizeof(desc);
877 				if (sysctl(mib, (miblen / sizeof(int)) + 2,
878 					   &desc, &desclen, NULL, 0) < 0) {
879 					snprintf(jail_errmsg,
880 					    JAIL_ERRMSGLEN,
881 					    "sysctl(0.4.%s): %s", desc.s,
882 					    strerror(errno));
883 					return (-1);
884 				}
885 				if ((desc.i & CTLTYPE) == CTLTYPE_INT &&
886 				    desc.s[0] == 'B') {
887 					jp->jp_ctltype = desc.i;
888 					jp->jp_flags |= JP_NOBOOL;
889 					jp->jp_valuelen = sizeof(int);
890 					return (0);
891 				}
892 			}
893 		}
894 	unknown_parameter:
895 		snprintf(jail_errmsg, JAIL_ERRMSGLEN,
896 		    "unknown parameter: %s", jp->jp_name);
897 		errno = ENOENT;
898 		return (-1);
899 	}
900  mib_desc:
901 	mib[1] = 4;
902 	desclen = sizeof(desc);
903 	if (sysctl(mib, (miblen / sizeof(int)) + 2, &desc, &desclen,
904 	    NULL, 0) < 0) {
905 		snprintf(jail_errmsg, JAIL_ERRMSGLEN,
906 		    "sysctl(0.4.%s): %s", jp->jp_name, strerror(errno));
907 		return (-1);
908 	}
909 	/* See if this is an array type. */
910 	p = strchr(desc.s, '\0');
911 	isarray  = 0;
912 	if (p - 2 < desc.s || strcmp(p - 2, ",a"))
913 		isarray = 0;
914 	else {
915 		isarray = 1;
916 		p[-2] = 0;
917 	}
918 	/* Look for types we understand */
919 	jp->jp_ctltype = desc.i;
920 	switch (desc.i & CTLTYPE) {
921 	case CTLTYPE_INT:
922 		if (desc.s[0] == 'B')
923 			jp->jp_flags |= JP_BOOL;
924 		else if (!strcmp(desc.s, "E,jailsys"))
925 			jp->jp_flags |= JP_JAILSYS;
926 	case CTLTYPE_UINT:
927 		jp->jp_valuelen = sizeof(int);
928 		break;
929 	case CTLTYPE_LONG:
930 	case CTLTYPE_ULONG:
931 		jp->jp_valuelen = sizeof(long);
932 		break;
933 	case CTLTYPE_QUAD:
934 		jp->jp_valuelen = sizeof(int64_t);
935 		break;
936 	case CTLTYPE_STRING:
937 		desc.s[0] = 0;
938 		desclen = sizeof(desc.s);
939 		if (sysctl(mib + 2, miblen / sizeof(int), desc.s, &desclen,
940 		    NULL, 0) < 0) {
941 			snprintf(jail_errmsg, JAIL_ERRMSGLEN,
942 			    "sysctl(" SJPARAM ".%s): %s", jp->jp_name,
943 			    strerror(errno));
944 			return (-1);
945 		}
946 		jp->jp_valuelen = strtoul(desc.s, NULL, 10);
947 		break;
948 	case CTLTYPE_STRUCT:
949 		if (!strcmp(desc.s, "S,in_addr")) {
950 			jp->jp_structtype = JPS_IN_ADDR;
951 			jp->jp_valuelen = sizeof(struct in_addr);
952 		} else if (!strcmp(desc.s, "S,in6_addr")) {
953 			jp->jp_structtype = JPS_IN6_ADDR;
954 			jp->jp_valuelen = sizeof(struct in6_addr);
955 		} else {
956 			desclen = 0;
957 			if (sysctl(mib + 2, miblen / sizeof(int),
958 			    NULL, &jp->jp_valuelen, NULL, 0) < 0) {
959 				snprintf(jail_errmsg, JAIL_ERRMSGLEN,
960 				    "sysctl(" SJPARAM ".%s): %s", jp->jp_name,
961 				    strerror(errno));
962 				return (-1);
963 			}
964 		}
965 		break;
966 	case CTLTYPE_NODE:
967 		/* A node might be described by an empty-named child. */
968 		mib[1] = 1;
969 		mib[(miblen / sizeof(int)) + 2] =
970 		    mib[(miblen / sizeof(int)) + 1] - 1;
971 		miblen += sizeof(int);
972 		desclen = sizeof(desc.s);
973 		if (sysctl(mib, (miblen / sizeof(int)) + 2, desc.s, &desclen,
974 		    NULL, 0) < 0) {
975 			snprintf(jail_errmsg, JAIL_ERRMSGLEN,
976 			    "sysctl(0.1): %s", strerror(errno));
977 			return (-1);
978 		}
979 		if (desc.s[desclen - 2] != '.')
980 			goto unknown_parameter;
981 		goto mib_desc;
982 	default:
983 		snprintf(jail_errmsg, JAIL_ERRMSGLEN,
984 		    "unknown type for %s", jp->jp_name);
985 		errno = ENOENT;
986 		return (-1);
987 	}
988 	if (isarray) {
989 		jp->jp_elemlen = jp->jp_valuelen;
990 		jp->jp_valuelen = 0;
991 	}
992 	return (0);
993 }
994 
995 /*
996  * Change a boolean parameter name into its "no" counterpart or vice versa.
997  */
998 static char *
999 noname(const char *name)
1000 {
1001 	char *nname, *p;
1002 
1003 	nname = malloc(strlen(name) + 3);
1004 	if (nname == NULL) {
1005 		strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
1006 		return (NULL);
1007 	}
1008 	p = strrchr(name, '.');
1009 	if (p != NULL)
1010 		sprintf(nname, "%.*s.no%s", (int)(p - name), name, p + 1);
1011 	else
1012 		sprintf(nname, "no%s", name);
1013 	return (nname);
1014 }
1015 
1016 static char *
1017 nononame(const char *name)
1018 {
1019 	char *p, *nname;
1020 
1021 	p = strrchr(name, '.');
1022 	if (strncmp(p ? p + 1 : name, "no", 2)) {
1023 		snprintf(jail_errmsg, sizeof(jail_errmsg),
1024 		    "mismatched boolean: %s", name);
1025 		errno = EINVAL;
1026 		return (NULL);
1027 	}
1028 	nname = malloc(strlen(name) - 1);
1029 	if (nname == NULL) {
1030 		strerror_r(errno, jail_errmsg, JAIL_ERRMSGLEN);
1031 		return (NULL);
1032 	}
1033 	if (p != NULL)
1034 		sprintf(nname, "%.*s.%s", (int)(p - name), name, p + 3);
1035 	else
1036 		strcpy(nname, name + 2);
1037 	return (nname);
1038 }
1039