freebsd-dev/usr.sbin/jail/state.c

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/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2011 James Gritton
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/uio.h>
#include <err.h>
#include <stdlib.h>
#include <string.h>
#include "jailp.h"
struct cfjails ready = TAILQ_HEAD_INITIALIZER(ready);
struct cfjails depend = TAILQ_HEAD_INITIALIZER(depend);
static void dep_add(struct cfjail *from, struct cfjail *to, unsigned flags);
static int cmp_jailptr(const void *a, const void *b);
static int cmp_jailptr_name(const void *a, const void *b);
static struct cfjail *find_jail(const char *name);
static struct cfjail *running_jail(const char *name, int flags);
static struct cfjail **jails_byname;
static size_t njails;
/*
* Set up jail dependency lists.
*/
void
dep_setup(int docf)
{
struct cfjail *j, *dj;
struct cfparam *p;
struct cfstring *s;
struct cfdepend *d;
const char *cs;
char *pname;
size_t plen;
int deps, ldeps;
if (!docf) {
/*
* With no config file, let "depend" for a single jail
* look at currently running jails.
*/
if ((j = TAILQ_FIRST(&cfjails)) &&
(p = j->intparams[IP_DEPEND])) {
TAILQ_FOREACH(s, &p->val, tq) {
if (running_jail(s->s, 0) == NULL) {
warnx("depends on nonexistent jail "
"\"%s\"", s->s);
j->flags |= JF_FAILED;
}
}
}
return;
}
njails = 0;
TAILQ_FOREACH(j, &cfjails, tq)
njails++;
jails_byname = emalloc(njails * sizeof(struct cfjail *));
njails = 0;
TAILQ_FOREACH(j, &cfjails, tq)
jails_byname[njails++] = j;
qsort(jails_byname, njails, sizeof(struct cfjail *), cmp_jailptr);
deps = 0;
ldeps = 0;
plen = 0;
pname = NULL;
TAILQ_FOREACH(j, &cfjails, tq) {
if (j->flags & JF_FAILED)
continue;
if ((p = j->intparams[IP_DEPEND])) {
TAILQ_FOREACH(s, &p->val, tq) {
dj = find_jail(s->s);
if (dj != NULL) {
deps++;
dep_add(j, dj, 0);
} else {
jail_warnx(j,
"depends on undefined jail \"%s\"",
s->s);
j->flags |= JF_FAILED;
}
}
}
/* A jail has an implied dependency on its parent. */
if ((cs = strrchr(j->name, '.')))
{
if (plen < (size_t)(cs - j->name + 1)) {
plen = (cs - j->name) + 1;
pname = erealloc(pname, plen);
}
strlcpy(pname, j->name, plen);
dj = find_jail(pname);
if (dj != NULL) {
ldeps++;
dep_add(j, dj, DF_LIGHT);
}
}
}
/* Look for dependency loops. */
if (deps && (deps > 1 || ldeps)) {
(void)start_state(NULL, 0, 0, 0);
while ((j = TAILQ_FIRST(&ready))) {
requeue(j, &cfjails);
dep_done(j, DF_NOFAIL);
}
while ((j = TAILQ_FIRST(&depend)) != NULL) {
jail_warnx(j, "dependency loop");
j->flags |= JF_FAILED;
do {
requeue(j, &cfjails);
dep_done(j, DF_NOFAIL);
} while ((j = TAILQ_FIRST(&ready)));
}
TAILQ_FOREACH(j, &cfjails, tq)
STAILQ_FOREACH(d, &j->dep[DEP_FROM], tq[DEP_FROM])
d->flags &= ~DF_SEEN;
}
if (pname != NULL)
free(pname);
}
/*
* Return if a jail has dependencies.
*/
int
dep_check(struct cfjail *j)
{
int reset, depfrom, depto, ndeps, rev;
struct cfjail *dj;
struct cfdepend *d;
static int bits[] = { 0, 1, 1, 2, 1, 2, 2, 3 };
if (j->ndeps == 0)
return 0;
ndeps = 0;
if ((rev = JF_DO_STOP(j->flags))) {
depfrom = DEP_TO;
depto = DEP_FROM;
} else {
depfrom = DEP_FROM;
depto = DEP_TO;
}
STAILQ_FOREACH(d, &j->dep[depfrom], tq[depfrom]) {
if (d->flags & DF_SEEN)
continue;
dj = d->j[depto];
if (dj->flags & JF_FAILED) {
if (!(j->flags & (JF_DEPEND | JF_FAILED)) &&
verbose >= 0)
jail_warnx(j, "skipped");
j->flags |= JF_FAILED;
continue;
}
/*
* The dependee's state may be set (or changed) as a result of
* being in a dependency it wasn't in earlier.
*/
reset = 0;
if (bits[dj->flags & JF_OP_MASK] <= 1) {
if (!(dj->flags & JF_OP_MASK)) {
reset = 1;
dj->flags |= JF_DEPEND;
requeue(dj, &ready);
}
/* Set or change the dependee's state. */
switch (j->flags & JF_OP_MASK) {
case JF_START:
dj->flags |= JF_START;
break;
case JF_SET:
if (!(dj->flags & JF_OP_MASK))
dj->flags |= JF_SET;
else if (dj->flags & JF_STOP)
dj->flags |= JF_START;
break;
case JF_STOP:
case JF_RESTART:
if (!(dj->flags & JF_STOP))
reset = 1;
dj->flags |= JF_STOP;
if (dj->flags & JF_SET)
dj->flags ^= (JF_START | JF_SET);
break;
}
}
if (reset)
dep_reset(dj);
if (!((d->flags & DF_LIGHT) &&
(rev ? dj->jid < 0 : dj->jid > 0)))
ndeps++;
}
if (ndeps == 0)
return 0;
requeue(j, &depend);
return 1;
}
/*
* Resolve any dependencies from a finished jail.
*/
void
dep_done(struct cfjail *j, unsigned flags)
{
struct cfjail *dj;
struct cfdepend *d;
int depfrom, depto;
if (JF_DO_STOP(j->flags)) {
depfrom = DEP_TO;
depto = DEP_FROM;
} else {
depfrom = DEP_FROM;
depto = DEP_TO;
}
STAILQ_FOREACH(d, &j->dep[depto], tq[depto]) {
if ((d->flags & DF_SEEN) | (flags & ~d->flags & DF_LIGHT))
continue;
d->flags |= DF_SEEN;
dj = d->j[depfrom];
if (!(flags & DF_NOFAIL) && (j->flags & JF_FAILED) &&
(j->flags & (JF_OP_MASK | JF_DEPEND)) !=
(JF_SET | JF_DEPEND)) {
if (!(dj->flags & (JF_DEPEND | JF_FAILED)) &&
verbose >= 0)
jail_warnx(dj, "skipped");
dj->flags |= JF_FAILED;
}
if (!--dj->ndeps && dj->queue == &depend)
requeue(dj, &ready);
}
}
/*
* Count a jail's dependencies and mark them as unseen.
*/
void
dep_reset(struct cfjail *j)
{
int depfrom;
struct cfdepend *d;
depfrom = JF_DO_STOP(j->flags) ? DEP_TO : DEP_FROM;
j->ndeps = 0;
STAILQ_FOREACH(d, &j->dep[depfrom], tq[depfrom])
j->ndeps++;
}
/*
* Find the next jail ready to do something.
*/
struct cfjail *
next_jail(void)
{
struct cfjail *j;
if (!(j = next_proc(!TAILQ_EMPTY(&ready))) &&
(j = TAILQ_FIRST(&ready)) && JF_DO_STOP(j->flags) &&
(j = TAILQ_LAST(&ready, cfjails)) && !JF_DO_STOP(j->flags)) {
TAILQ_FOREACH_REVERSE(j, &ready, cfjails, tq)
if (JF_DO_STOP(j->flags))
break;
}
if (j != NULL)
requeue(j, &cfjails);
return j;
}
/*
* Set jails to the proper start state.
*/
int
start_state(const char *target, int docf, unsigned state, int running)
{
struct iovec jiov[6];
struct cfjail *j, *tj;
int jid;
char namebuf[MAXHOSTNAMELEN];
if (!target || (!docf && state != JF_STOP) ||
(!running && !strcmp(target, "*"))) {
/*
* For a global wildcard (including no target specified),
* set the state on all jails and start with those that
* have no dependencies.
*/
TAILQ_FOREACH_SAFE(j, &cfjails, tq, tj) {
j->flags = (j->flags & JF_FAILED) | state |
(docf ? JF_WILD : 0);
dep_reset(j);
requeue(j, j->ndeps ? &depend : &ready);
}
} else if (wild_jail_name(target)) {
/*
* For targets specified singly, or with a non-global wildcard,
* set their state and call them ready (even if there are
* dependencies). Leave everything else unqueued for now.
*/
if (running) {
/*
* -R matches its wildcards against currently running
* jails, not against the config file.
*/
jiov[0].iov_base = __DECONST(char *, "lastjid");
jiov[0].iov_len = sizeof("lastjid");
jiov[1].iov_base = &jid;
jiov[1].iov_len = sizeof(jid);
jiov[2].iov_base = __DECONST(char *, "jid");
jiov[2].iov_len = sizeof("jid");
jiov[3].iov_base = &jid;
jiov[3].iov_len = sizeof(jid);
jiov[4].iov_base = __DECONST(char *, "name");
jiov[4].iov_len = sizeof("name");
jiov[5].iov_base = &namebuf;
jiov[5].iov_len = sizeof(namebuf);
for (jid = 0; jail_get(jiov, 6, 0) > 0; ) {
if (wild_jail_match(namebuf, target)) {
j = add_jail();
j->name = estrdup(namebuf);
j->jid = jid;
j->flags = (j->flags & JF_FAILED) |
state | JF_WILD;
dep_reset(j);
requeue(j, &ready);
}
}
} else {
TAILQ_FOREACH_SAFE(j, &cfjails, tq, tj) {
if (wild_jail_match(j->name, target)) {
j->flags = (j->flags & JF_FAILED) |
state | JF_WILD;
dep_reset(j);
requeue(j, &ready);
}
}
}
} else {
j = find_jail(target);
if (j == NULL && state == JF_STOP) {
/* Allow -[rR] to specify a currently running jail. */
j = running_jail(target, JAIL_DYING);
}
if (j == NULL) {
warnx("\"%s\" not found", target);
return -1;
}
j->flags = (j->flags & JF_FAILED) | state;
dep_reset(j);
requeue(j, &ready);
}
return 0;
}
/*
* Move a jail to a new list.
*/
void
requeue(struct cfjail *j, struct cfjails *queue)
{
if (j->queue != queue) {
TAILQ_REMOVE(j->queue, j, tq);
TAILQ_INSERT_TAIL(queue, j, tq);
j->queue = queue;
}
}
void
requeue_head(struct cfjail *j, struct cfjails *queue)
{
TAILQ_REMOVE(j->queue, j, tq);
TAILQ_INSERT_HEAD(queue, j, tq);
j->queue = queue;
}
/*
* Add a dependency edge between two jails.
*/
static void
dep_add(struct cfjail *from, struct cfjail *to, unsigned flags)
{
struct cfdepend *d;
d = emalloc(sizeof(struct cfdepend));
d->flags = flags;
d->j[DEP_FROM] = from;
d->j[DEP_TO] = to;
STAILQ_INSERT_TAIL(&from->dep[DEP_FROM], d, tq[DEP_FROM]);
STAILQ_INSERT_TAIL(&to->dep[DEP_TO], d, tq[DEP_TO]);
}
/*
* Compare jail pointers for qsort/bsearch.
*/
static int
cmp_jailptr(const void *a, const void *b)
{
return strcmp((*((struct cfjail * const *)a))->name,
((*(struct cfjail * const *)b))->name);
}
static int
cmp_jailptr_name(const void *a, const void *b)
{
return strcmp((const char *)a, ((*(struct cfjail * const *)b))->name);
}
/*
* Find a jail object by name.
*/
static struct cfjail *
find_jail(const char *name)
{
struct cfjail **jp;
if (jails_byname == NULL)
return NULL;
jp = bsearch(name, jails_byname, njails, sizeof(struct cfjail *),
cmp_jailptr_name);
return jp ? *jp : NULL;
}
/*
* Return jail if it is running, and NULL if it isn't.
*/
static struct cfjail *
running_jail(const char *name, int flags)
{
struct iovec jiov[4];
struct cfjail *jail;
char *ep;
char jailname[MAXHOSTNAMELEN];
int jid, ret, len;
if ((jid = strtol(name, &ep, 10)) && !*ep) {
memset(jailname,0,sizeof(jailname));
len = sizeof(jailname);
} else {
strncpy(jailname, name,sizeof(jailname));
len = strlen(name) + 1;
jid = 0;
}
jiov[0].iov_base = __DECONST(char *, "jid");
jiov[0].iov_len = sizeof("jid");
jiov[1].iov_base = &jid;
jiov[1].iov_len = sizeof(jid);
jiov[2].iov_base = __DECONST(char *, "name");
jiov[2].iov_len = sizeof("name");
jiov[3].iov_base = &jailname;
jiov[3].iov_len = len;
if ((ret = jail_get(jiov, 4, flags)) < 0)
return (NULL);
if ((jail = find_jail(jailname)) == NULL) {
jail = add_jail();
jail->name = estrdup(jailname);
jail->jid = ret;
}
return (jail);
}