usr.sbin/jail/state.c

   1 /*-
   2  * Copyright (c) 2011 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/uio.h>
  31
  32 #include <err.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35
  36 #include "jailp.h"
  37
  38 struct cfjails ready = TAILQ_HEAD_INITIALIZER(ready);
  39 struct cfjails depend = TAILQ_HEAD_INITIALIZER(depend);
  40
  41 static void dep_add(struct cfjail *from, struct cfjail *to, unsigned flags);
  42 static int cmp_jailptr(const void *a, const void *b);
  43 static int cmp_jailptr_name(const void *a, const void *b);
  44 static struct cfjail *find_jail(const char *name);
  45 static int running_jid(const char *name, int flags);
  46
  47 static struct cfjail **jails_byname;
  48 static size_t njails;
  49
  50 /*
  51  * Set up jail dependency lists.
  52  */
  53 void
  54 dep_setup(int docf)
  55 {
  56         struct cfjail *j, *dj;
  57         struct cfparam *p;
  58         struct cfstring *s;
  59         struct cfdepend *d;
  60         const char *cs;
  61         char *pname;
  62         size_t plen;
  63         int deps, ldeps;
  64
  65         if (!docf) {
  66                 /*
  67                  * With no config file, let "depend" for a single jail
  68                  * look at currently running jails.
  69                  */
  70                 if ((j = TAILQ_FIRST(&cfjails)) &&
  71                     (p = j->intparams[IP_DEPEND])) {
  72                         TAILQ_FOREACH(s, &p->val, tq) {
  73                                 if (running_jid(s->s, 0) < 0) {
  74                                         warnx("depends on nonexistent jail "
  75                                             "\"%s\"", s->s);
  76                                         j->flags |= JF_FAILED;
  77                                 }
  78                         }
  79                 }
  80                 return;
  81         }
  82
  83         njails = 0;
  84         TAILQ_FOREACH(j, &cfjails, tq)
  85                 njails++;
  86         jails_byname = emalloc(njails * sizeof(struct cfjail *));
  87         njails = 0;
  88         TAILQ_FOREACH(j, &cfjails, tq)
  89                 jails_byname[njails++] = j;
  90         qsort(jails_byname, njails, sizeof(struct cfjail *), cmp_jailptr);
  91         deps = 0;
  92         ldeps = 0;
  93         plen = 0;
  94         pname = NULL;
  95         TAILQ_FOREACH(j, &cfjails, tq) {
  96                 if (j->flags & JF_FAILED)
  97                         continue;
  98                 if ((p = j->intparams[IP_DEPEND])) {
  99                         TAILQ_FOREACH(s, &p->val, tq) {
 100                                 dj = find_jail(s->s);
 101                                 if (dj != NULL) {
 102                                         deps++;
 103                                         dep_add(j, dj, 0);
 104                                 } else {
 105                                         jail_warnx(j,
 106                                             "depends on undefined jail \"%s\"",
 107                                             s->s);
 108                                         j->flags |= JF_FAILED;
 109                                 }
 110                         }
 111                 }
 112                 /* A jail has an implied dependency on its parent. */
 113                 if ((cs = strrchr(j->name, '.')))
 114                 {
 115                         if (plen < (size_t)(cs - j->name + 1)) {
 116                                 plen = (cs - j->name) + 1;
 117                                 pname = erealloc(pname, plen);
 118                         }
 119                         strlcpy(pname, j->name, plen);
 120                         dj = find_jail(pname);
 121                         if (dj != NULL) {
 122                                 ldeps++;
 123                                 dep_add(j, dj, DF_LIGHT);
 124                         }
 125                 }
 126         }
 127
 128         /* Look for dependency loops. */
 129         if (deps && (deps > 1 || ldeps)) {
 130                 (void)start_state(NULL, 0, 0, 0);
 131                 while ((j = TAILQ_FIRST(&ready))) {
 132                         requeue(j, &cfjails);
 133                         dep_done(j, DF_NOFAIL);
 134                 }
 135                 while ((j = TAILQ_FIRST(&depend)) != NULL) {
 136                         jail_warnx(j, "dependency loop");
 137                         j->flags |= JF_FAILED;
 138                         do {
 139                                 requeue(j, &cfjails);
 140                                 dep_done(j, DF_NOFAIL);
 141                         } while ((j = TAILQ_FIRST(&ready)));
 142                 }
 143                 TAILQ_FOREACH(j, &cfjails, tq)
 144                         STAILQ_FOREACH(d, &j->dep[DEP_FROM], tq[DEP_FROM])
 145                                 d->flags &= ~DF_SEEN;
 146         }
 147         if (pname != NULL)
 148                 free(pname);
 149 }
 150
 151 /*
 152  * Return if a jail has dependencies.
 153  */
 154 int
 155 dep_check(struct cfjail *j)
 156 {
 157         int reset, depfrom, depto, ndeps, rev;
 158         struct cfjail *dj;
 159         struct cfdepend *d;
 160
 161         static int bits[] = { 0, 1, 1, 2, 1, 2, 2, 3 };
 162
 163         if (j->ndeps == 0)
 164                 return 0;
 165         ndeps = 0;
 166         if ((rev = JF_DO_STOP(j->flags))) {
 167                 depfrom = DEP_TO;
 168                 depto = DEP_FROM;
 169         } else {
 170                 depfrom = DEP_FROM;
 171                 depto = DEP_TO;
 172         }
 173         STAILQ_FOREACH(d, &j->dep[depfrom], tq[depfrom]) {
 174                 if (d->flags & DF_SEEN)
 175                         continue;
 176                 dj = d->j[depto];
 177                 if (dj->flags & JF_FAILED) {
 178                         if (!(j->flags & (JF_DEPEND | JF_FAILED)) &&
 179                             verbose >= 0)
 180                                 jail_warnx(j, "skipped");
 181                         j->flags |= JF_FAILED;
 182                         continue;
 183                 }
 184                 /*
 185                  * The dependee's state may be set (or changed) as a result of
 186                  * being in a dependency it wasn't in earlier.
 187                  */
 188                 reset = 0;
 189                 if (bits[dj->flags & JF_OP_MASK] <= 1) {
 190                         if (!(dj->flags & JF_OP_MASK)) {
 191                                 reset = 1;
 192                                 dj->flags |= JF_DEPEND;
 193                                 requeue(dj, &ready);
 194                         }
 195                         /* Set or change the dependee's state. */
 196                         switch (j->flags & JF_OP_MASK) {
 197                         case JF_START:
 198                                 dj->flags |= JF_START;
 199                                 break;
 200                         case JF_SET:
 201                                 if (!(dj->flags & JF_OP_MASK))
 202                                         dj->flags |= JF_SET;
 203                                 else if (dj->flags & JF_STOP)
 204                                         dj->flags |= JF_START;
 205                                 break;
 206                         case JF_STOP:
 207                         case JF_RESTART:
 208                                 if (!(dj->flags & JF_STOP))
 209                                         reset = 1;
 210                                 dj->flags |= JF_STOP;
 211                                 if (dj->flags & JF_SET)
 212                                         dj->flags ^= (JF_START | JF_SET);
 213                                 break;
 214                         }
 215                 }
 216                 if (reset)
 217                         dep_reset(dj);
 218                 if (!((d->flags & DF_LIGHT) &&
 219                     (rev ? dj->jid < 0 : dj->jid > 0)))
 220                         ndeps++;
 221         }
 222         if (ndeps == 0)
 223                 return 0;
 224         requeue(j, &depend);
 225         return 1;
 226 }
 227
 228 /*
 229  * Resolve any dependencies from a finished jail.
 230  */
 231 void
 232 dep_done(struct cfjail *j, unsigned flags)
 233 {
 234         struct cfjail *dj;
 235         struct cfdepend *d;
 236         int depfrom, depto;
 237
 238         if (JF_DO_STOP(j->flags)) {
 239                 depfrom = DEP_TO;
 240                 depto = DEP_FROM;
 241         } else {
 242                 depfrom = DEP_FROM;
 243                 depto = DEP_TO;
 244         }
 245         STAILQ_FOREACH(d, &j->dep[depto], tq[depto]) {
 246                 if ((d->flags & DF_SEEN) | (flags & ~d->flags & DF_LIGHT))
 247                         continue;
 248                 d->flags |= DF_SEEN;
 249                 dj = d->j[depfrom];
 250                 if (!(flags & DF_NOFAIL) && (j->flags & JF_FAILED) &&
 251                     (j->flags & (JF_OP_MASK | JF_DEPEND)) !=
 252                     (JF_SET | JF_DEPEND)) {
 253                         if (!(dj->flags & (JF_DEPEND | JF_FAILED)) &&
 254                             verbose >= 0)
 255                                 jail_warnx(dj, "skipped");
 256                         dj->flags |= JF_FAILED;
 257                 }
 258                 if (!--dj->ndeps && dj->queue == &depend)
 259                         requeue(dj, &ready);
 260         }
 261 }
 262
 263 /*
 264  * Count a jail's dependencies and mark them as unseen.
 265  */
 266 void
 267 dep_reset(struct cfjail *j)
 268 {
 269         int depfrom;
 270         struct cfdepend *d;
 271
 272         depfrom = JF_DO_STOP(j->flags) ? DEP_TO : DEP_FROM;
 273         j->ndeps = 0;
 274         STAILQ_FOREACH(d, &j->dep[depfrom], tq[depfrom])
 275                 j->ndeps++;
 276 }
 277
 278 /*
 279  * Find the next jail ready to do something.
 280  */
 281 struct cfjail *
 282 next_jail(void)
 283 {
 284         struct cfjail *j;
 285
 286         if (!(j = next_proc(!TAILQ_EMPTY(&ready))) &&
 287             (j = TAILQ_FIRST(&ready)) && JF_DO_STOP(j->flags) &&
 288             (j = TAILQ_LAST(&ready, cfjails)) && !JF_DO_STOP(j->flags)) {
 289                 TAILQ_FOREACH_REVERSE(j, &ready, cfjails, tq)
 290                         if (JF_DO_STOP(j->flags))
 291                                 break;
 292         }
 293         if (j != NULL)
 294                 requeue(j, &cfjails);
 295         return j;
 296 }
 297
 298 /*
 299  * Set jails to the proper start state.
 300  */
 301 int
 302 start_state(const char *target, int docf, unsigned state, int running)
 303 {
 304         struct iovec jiov[6];
 305         struct cfjail *j, *tj;
 306         int jid;
 307         char namebuf[MAXHOSTNAMELEN];
 308
 309         if (!target || (!docf && state != JF_STOP) ||
 310             (!running && !strcmp(target, "*"))) {
 311                 /*
 312                  * For a global wildcard (including no target specified),
 313                  * set the state on all jails and start with those that
 314                  * have no dependencies.
 315                  */
 316                 TAILQ_FOREACH_SAFE(j, &cfjails, tq, tj) {
 317                         j->flags = (j->flags & JF_FAILED) | state |
 318                             (docf ? JF_WILD : 0);
 319                         dep_reset(j);
 320                         requeue(j, j->ndeps ? &depend : &ready);
 321                 }
 322         } else if (wild_jail_name(target)) {
 323                 /*
 324                  * For targets specified singly, or with a non-global wildcard,
 325                  * set their state and call them ready (even if there are
 326                  * dependencies).  Leave everything else unqueued for now.
 327                  */
 328                 if (running) {
 329                         /*
 330                          * -R matches its wildcards against currently running
 331                          * jails, not against the config file.
 332                          */
 333                         jiov[0].iov_base = __DECONST(char *, "lastjid");
 334                         jiov[0].iov_len = sizeof("lastjid");
 335                         jiov[1].iov_base = &jid;
 336                         jiov[1].iov_len = sizeof(jid);
 337                         jiov[2].iov_base = __DECONST(char *, "jid");
 338                         jiov[2].iov_len = sizeof("jid");
 339                         jiov[3].iov_base = &jid;
 340                         jiov[3].iov_len = sizeof(jid);
 341                         jiov[4].iov_base = __DECONST(char *, "name");
 342                         jiov[4].iov_len = sizeof("name");
 343                         jiov[5].iov_base = &namebuf;
 344                         jiov[5].iov_len = sizeof(namebuf);
 345                         for (jid = 0; jail_get(jiov, 6, 0) > 0; ) {
 346                                 if (wild_jail_match(namebuf, target)) {
 347                                         j = add_jail();
 348                                         j->name = estrdup(namebuf);
 349                                         j->jid = jid;
 350                                         j->flags = (j->flags & JF_FAILED) |
 351                                             state | JF_WILD;
 352                                         dep_reset(j);
 353                                         requeue(j, &ready);
 354                                 }
 355                         }
 356                 } else {
 357                         TAILQ_FOREACH_SAFE(j, &cfjails, tq, tj) {
 358                                 if (wild_jail_match(j->name, target)) {
 359                                         j->flags = (j->flags & JF_FAILED) |
 360                                             state | JF_WILD;
 361                                         dep_reset(j);
 362                                         requeue(j, &ready);
 363                                 }
 364                         }
 365                 }
 366         } else {
 367                 j = find_jail(target);
 368                 if (j == NULL && state == JF_STOP) {
 369                         /* Allow -[rR] to specify a currently running jail. */
 370                         if ((jid = running_jid(target, JAIL_DYING)) > 0) {
 371                                 j = add_jail();
 372                                 j->name = estrdup(target);
 373                                 j->jid = jid;
 374                         }
 375                 }
 376                 if (j == NULL) {
 377                         warnx("\"%s\" not found", target);
 378                         return -1;
 379                 }
 380                 j->flags = (j->flags & JF_FAILED) | state;
 381                 dep_reset(j);
 382                 requeue(j, &ready);
 383         }
 384         return 0;
 385 }
 386
 387 /*
 388  * Move a jail to a new list.
 389  */
 390 void
 391 requeue(struct cfjail *j, struct cfjails *queue)
 392 {
 393         if (j->queue != queue) {
 394                 TAILQ_REMOVE(j->queue, j, tq);
 395                 TAILQ_INSERT_TAIL(queue, j, tq);
 396                 j->queue = queue;
 397         }
 398 }
 399
 400 /*
 401  * Add a dependency edge between two jails.
 402  */
 403 static void
 404 dep_add(struct cfjail *from, struct cfjail *to, unsigned flags)
 405 {
 406         struct cfdepend *d;
 407
 408         d = emalloc(sizeof(struct cfdepend));
 409         d->flags = flags;
 410         d->j[DEP_FROM] = from;
 411         d->j[DEP_TO] = to;
 412         STAILQ_INSERT_TAIL(&from->dep[DEP_FROM], d, tq[DEP_FROM]);
 413         STAILQ_INSERT_TAIL(&to->dep[DEP_TO], d, tq[DEP_TO]);
 414 }
 415
 416 /*
 417  * Compare jail pointers for qsort/bsearch.
 418  */
 419 static int
 420 cmp_jailptr(const void *a, const void *b)
 421 {
 422         return strcmp((*((struct cfjail * const *)a))->name,
 423             ((*(struct cfjail * const *)b))->name);
 424 }
 425
 426 static int
 427 cmp_jailptr_name(const void *a, const void *b)
 428 {
 429         return strcmp((const char *)a, ((*(struct cfjail * const *)b))->name);
 430 }
 431
 432 /*
 433  * Find a jail object by name.
 434  */
 435 static struct cfjail *
 436 find_jail(const char *name)
 437 {
 438         struct cfjail **jp;
 439
 440         jp = bsearch(name, jails_byname, njails, sizeof(struct cfjail *),
 441             cmp_jailptr_name);
 442         return jp ? *jp : NULL;
 443 }
 444
 445 /*
 446  * Return the named jail's jid if it is running, and -1 if it isn't.
 447  */
 448 static int
 449 running_jid(const char *name, int flags)
 450 {
 451         struct iovec jiov[2];
 452         char *ep;
 453         int jid;
 454
 455         if ((jid = strtol(name, &ep, 10)) && !*ep) {
 456                 jiov[0].iov_base = __DECONST(char *, "jid");
 457                 jiov[0].iov_len = sizeof("jid");
 458                 jiov[1].iov_base = &jid;
 459                 jiov[1].iov_len = sizeof(jid);
 460         } else {
 461                 jiov[0].iov_base = __DECONST(char *, "name");
 462                 jiov[0].iov_len = sizeof("name");
 463                 jiov[1].iov_len = strlen(name) + 1;
 464                 jiov[1].iov_base = alloca(jiov[1].iov_len);
 465                 strcpy(jiov[1].iov_base, name);
 466         }
 467         return jail_get(jiov, 2, flags);
 468 }