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freebsd-skq/usr.sbin/jail/command.c

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Initial work on the new jail(8). There are more features to add, and some cleaning up to do on existing features, but this is pretty much what the final product will look like.
2010-10-20 20:42:33 +00:00
/*-
* Copyright (c) 2010 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/types.h>
#include <sys/event.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <sys/user.h>
#include <sys/wait.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <kvm.h>
#include <login_cap.h>
#include <paths.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "jailp.h"
#define COMSTRING_DUMMY ((struct cfstring *)1)
#define DEFAULT_STOP_TIMEOUT 10
#define PHASH_SIZE 256
LIST_HEAD(phhead, phash);
struct phash {
LIST_ENTRY(phash) le;
struct cfjail *j;
pid_t pid;
};
extern char **environ;
static int get_user_info(struct cfjail *j, const char *username,
const struct passwd **pwdp, login_cap_t **lcapp);
static void add_proc(struct cfjail *j, pid_t pid);
static void clear_procs(struct cfjail *j);
static struct cfjail *find_proc(pid_t pid);
Check paths for security: path must be absolute. mount paths must exist and have no symlinks beyond the jail's path itself. consolelog must exist (apart from the final component) and have no symlinks beyond the jail's path itself.
2010-11-04 18:40:29 +00:00
static int check_path(struct cfjail *j, const char *pname, const char *path,
int isfile);
Initial work on the new jail(8). There are more features to add, and some cleaning up to do on existing features, but this is pretty much what the final product will look like.
2010-10-20 20:42:33 +00:00
static struct cfjails sleeping = TAILQ_HEAD_INITIALIZER(sleeping);
static struct cfjails runnable = TAILQ_HEAD_INITIALIZER(runnable);
static struct phhead phash[PHASH_SIZE];
static int kq;
/*
* Run a command associated with a jail, possibly inside the jail.
*/
int
run_command(struct cfjail *j, int *plimit, enum intparam comparam)
{
const struct passwd *pwd;
struct cfstring *comstring, *s;
login_cap_t *lcap;
char **argv;
Check paths for security: path must be absolute. mount paths must exist and have no symlinks beyond the jail's path itself. consolelog must exist (apart from the final component) and have no symlinks beyond the jail's path itself.
2010-11-04 18:40:29 +00:00
char *cs, *addr, *comcs, *devpath;
Initial work on the new jail(8). There are more features to add, and some cleaning up to do on existing features, but this is pretty much what the final product will look like.
2010-10-20 20:42:33 +00:00
const char *jidstr, *conslog, *path, *ruleset, *term, *username;
size_t comlen;
pid_t pid;
int argc, bg, clean, consfd, down, fib, i, injail, sjuser, timeout;
static char *cleanenv;
if (comparam) {
if (comparam == IP_MOUNT_DEVFS
? !bool_param(j->intparams[IP_MOUNT_DEVFS])
: j->intparams[comparam] == NULL)
return 0;
j->comparam = comparam;
j->comstring = comparam == IP_MOUNT_DEVFS ? COMSTRING_DUMMY
: STAILQ_FIRST(&j->intparams[comparam]->val);
} else {
comparam = j->comparam;
if (!(j->flags & JF_RUNQ))
j->comstring = j->comstring == COMSTRING_DUMMY
? NULL : STAILQ_NEXT(j->comstring, tq);
}
comstring = j->comstring;
if (comstring == NULL ||
(comstring != COMSTRING_DUMMY && comstring->len == 0))
return 0;
if (plimit && *plimit == 0) {
j->flags |= JF_RUNQ;
requeue(j, &runnable);
return 1;
}
j->flags &= ~(JF_RUNQ | JF_BACKGROUND);
/*
* Collect exec arguments. Internal commands for network and
* mounting build their own argument lists (XXX they should be
* truly internal).
*/
bg = j->flags & JF_FAILED;
down = j->flags & (JF_STOP | JF_FAILED);
if (comparam == IP__IP4_IFADDR) {
argv = alloca(8 * sizeof(char *));
*(const char **)&argv[0] = _PATH_IFCONFIG;
if ((cs = strchr(comstring->s, '|'))) {
argv[1] = alloca(cs - comstring->s + 1);
strlcpy(argv[1], comstring->s, cs - comstring->s + 1);
addr = cs + 1;
} else {
*(const char **)&argv[1] =
string_param(j->intparams[IP_INTERFACE]);
addr = comstring->s;
}
*(const char **)&argv[2] = "inet";
if (!(cs = strchr(addr, '/'))) {
argv[3] = addr;
*(const char **)&argv[4] = "netmask";
*(const char **)&argv[5] = "255.255.255.255";
argc = 6;
} else if (strchr(cs + 1, '.')) {
argv[3] = alloca(cs - addr + 1);
strlcpy(argv[3], addr, cs - addr + 1);
*(const char **)&argv[4] = "netmask";
*(const char **)&argv[5] = cs + 1;
argc = 6;
} else {
argv[3] = addr;
argc = 4;
}
*(const char **)&argv[argc] = down ? "-alias" : "alias";
argv[argc + 1] = NULL;
j->flags |= JF_IFUP;
#ifdef INET6
} else if (comparam == IP__IP6_IFADDR) {
argv = alloca(8 * sizeof(char *));
*(const char **)&argv[0] = _PATH_IFCONFIG;
if ((cs = strchr(comstring->s, '|'))) {
argv[1] = alloca(cs - comstring->s + 1);
strlcpy(argv[1], comstring->s, cs - comstring->s + 1);
addr = cs + 1;
} else {
*(const char **)&argv[1] =
string_param(j->intparams[IP_INTERFACE]);
addr = comstring->s;
}
*(const char **)&argv[2] = "inet6";
argv[3] = addr;
if (!(cs = strchr(addr, '/'))) {
*(const char **)&argv[4] = "prefixlen";
*(const char **)&argv[5] = "128";
argc = 6;
} else
argc = 4;
*(const char **)&argv[argc] = down ? "-alias" : "alias";
argv[argc + 1] = NULL;
j->flags |= JF_IFUP;
#endif
} else if (comparam == IP_VNET_INTERFACE) {
argv = alloca(5 * sizeof(char *));
*(const char **)&argv[0] = _PATH_IFCONFIG;
argv[1] = comstring->s;
*(const char **)&argv[2] = down ? "-vnet" : "vnet";
jidstr = string_param(j->intparams[KP_JID]);
*(const char **)&argv[3] =
jidstr ? jidstr : string_param(j->intparams[KP_NAME]);
argv[4] = NULL;
j->flags |= JF_IFUP;
Reads the mount.fstab file, and put its lines separately into the IP__MOUNT_FROM_FSTAB internal parameter.
2010-11-04 17:01:21 +00:00
} else if (comparam == IP_MOUNT || comparam == IP__MOUNT_FROM_FSTAB) {
Initial work on the new jail(8). There are more features to add, and some cleaning up to do on existing features, but this is pretty much what the final product will look like.
2010-10-20 20:42:33 +00:00
argv = alloca(8 * sizeof(char *));
comcs = alloca(comstring->len + 1);
strcpy(comcs, comstring->s);
argc = 0;
for (cs = strtok(comcs, " \t\f\v\r\n"); cs && argc < 4;
cs = strtok(NULL, " \t\f\v\r\n"))
argv[argc++] = cs;
Check paths for security: path must be absolute. mount paths must exist and have no symlinks beyond the jail's path itself. consolelog must exist (apart from the final component) and have no symlinks beyond the jail's path itself.
2010-11-04 18:40:29 +00:00
if (argc == 0)
return 0;
Initial work on the new jail(8). There are more features to add, and some cleaning up to do on existing features, but this is pretty much what the final product will look like.
2010-10-20 20:42:33 +00:00
if (argc < 3) {
Reads the mount.fstab file, and put its lines separately into the IP__MOUNT_FROM_FSTAB internal parameter.
2010-11-04 17:01:21 +00:00
jail_warnx(j, "%s: %s: missing information",
j->intparams[comparam]->name, comstring->s);
Initial work on the new jail(8). There are more features to add, and some cleaning up to do on existing features, but this is pretty much what the final product will look like.
2010-10-20 20:42:33 +00:00
failed(j);
return -1;
}
Check paths for security: path must be absolute. mount paths must exist and have no symlinks beyond the jail's path itself. consolelog must exist (apart from the final component) and have no symlinks beyond the jail's path itself.
2010-11-04 18:40:29 +00:00
if (check_path(j, j->intparams[comparam]->name, argv[1], 0) < 0)
return -1;
Initial work on the new jail(8). There are more features to add, and some cleaning up to do on existing features, but this is pretty much what the final product will look like.
2010-10-20 20:42:33 +00:00
if (down) {
argv[4] = NULL;
argv[3] = argv[1];
*(const char **)&argv[0] = "/sbin/umount";
} else {
if (argc == 4) {
argv[7] = NULL;
argv[6] = argv[1];
argv[5] = argv[0];
argv[4] = argv[3];
*(const char **)&argv[3] = "-o";
} else {
argv[5] = NULL;
argv[4] = argv[1];
argv[3] = argv[0];
}
*(const char **)&argv[0] = _PATH_MOUNT;
}
*(const char **)&argv[1] = "-t";
j->flags |= JF_MOUNTED;
} else if (comparam == IP_MOUNT_DEVFS) {
path = string_param(j->intparams[KP_PATH]);
if (path == NULL) {
jail_warnx(j, "mount.devfs: no path");
failed(j);
return -1;
}
Check paths for security: path must be absolute. mount paths must exist and have no symlinks beyond the jail's path itself. consolelog must exist (apart from the final component) and have no symlinks beyond the jail's path itself.
2010-11-04 18:40:29 +00:00
devpath = alloca(strlen(path) + 5);
sprintf(devpath, "%s/dev", path);
if (check_path(j, "mount.devfs", devpath, 0) < 0)
return -1;
Initial work on the new jail(8). There are more features to add, and some cleaning up to do on existing features, but this is pretty much what the final product will look like.
2010-10-20 20:42:33 +00:00
if (down) {
argv = alloca(3 * sizeof(char *));
*(const char **)&argv[0] = "/sbin/umount";
Check paths for security: path must be absolute. mount paths must exist and have no symlinks beyond the jail's path itself. consolelog must exist (apart from the final component) and have no symlinks beyond the jail's path itself.
2010-11-04 18:40:29 +00:00
argv[1] = devpath;
Initial work on the new jail(8). There are more features to add, and some cleaning up to do on existing features, but this is pretty much what the final product will look like.
2010-10-20 20:42:33 +00:00
argv[2] = NULL;
} else {
argv = alloca(4 * sizeof(char *));
*(const char **)&argv[0] = _PATH_BSHELL;
*(const char **)&argv[1] = "-c";
ruleset = string_param(j->intparams
[IP_MOUNT_DEVFS_RULESET]);
argv[2] = alloca(strlen(path) +
(ruleset ? strlen(ruleset) + 1 : 0) + 56);
sprintf(argv[2], ". /etc/rc.subr; load_rc_config .; "
"devfs_mount_jail %s/dev%s%s", path,
ruleset ? " " : "", ruleset ? ruleset : "");
argv[3] = NULL;
}
j->flags |= JF_MOUNTED;
} else if (comparam == IP_COMMAND && j->name == NULL) {
argc = 0;
STAILQ_FOREACH(s, &j->intparams[IP_COMMAND]->val, tq)
argc++;
argv = alloca((argc + 1) * sizeof(char *));
argc = 0;
STAILQ_FOREACH(s, &j->intparams[IP_COMMAND]->val, tq)
argv[argc++] = s->s;
argv[argc] = NULL;
j->comstring = NULL;
} else if ((cs = strpbrk(comstring->s, "!\"$&'()*;<>?[\\]`{|}~")) &&
!(cs[0] == '&' && cs[1] == '\0')) {
argv = alloca(4 * sizeof(char *));
*(const char **)&argv[0] = _PATH_BSHELL;
*(const char **)&argv[1] = "-c";
argv[2] = comstring->s;
argv[3] = NULL;
} else {
if (cs) {
*cs = 0;
bg = 1;
}
comcs = alloca(comstring->len + 1);
strcpy(comcs, comstring->s);
argc = 0;
for (cs = strtok(comcs, " \t\f\v\r\n"); cs;
cs = strtok(NULL, " \t\f\v\r\n"))
argc++;
argv = alloca((argc + 1) * sizeof(char *));
strcpy(comcs, comstring->s);
argc = 0;
for (cs = strtok(comcs, " \t\f\v\r\n"); cs;
cs = strtok(NULL, " \t\f\v\r\n"))
argv[argc++] = cs;
argv[argc] = NULL;
}
if (argv[0] == NULL)
return 0;
j->pstatus = 0;
if (int_param(j->intparams[IP_EXEC_TIMEOUT], &timeout) &&
timeout != 0) {
clock_gettime(CLOCK_REALTIME, &j->timeout);
j->timeout.tv_sec += timeout;
} else
j->timeout.tv_sec = 0;
injail = comparam == IP_EXEC_START || comparam == IP_COMMAND ||
comparam == IP_EXEC_STOP;
clean = bool_param(j->intparams[IP_EXEC_CLEAN]);
username = string_param(j->intparams[injail
? IP_EXEC_JAIL_USER : IP_EXEC_SYSTEM_USER]);
sjuser = bool_param(j->intparams[IP_EXEC_SYSTEM_JAIL_USER]);
consfd = 0;
if (injail &&
(conslog = string_param(j->intparams[IP_EXEC_CONSOLELOG]))) {
Check paths for security: path must be absolute. mount paths must exist and have no symlinks beyond the jail's path itself. consolelog must exist (apart from the final component) and have no symlinks beyond the jail's path itself.
2010-11-04 18:40:29 +00:00
if (check_path(j, "exec.consolelog", conslog, 1) < 0)
return -1;
Initial work on the new jail(8). There are more features to add, and some cleaning up to do on existing features, but this is pretty much what the final product will look like.
2010-10-20 20:42:33 +00:00
consfd =
open(conslog, O_WRONLY | O_CREAT | O_APPEND, DEFFILEMODE);
if (consfd < 0) {
jail_warnx(j, "open %s: %s", conslog, strerror(errno));
failed(j);
return -1;
}
}
comlen = 0;
for (i = 0; argv[i]; i++)
comlen += strlen(argv[i]) + 1;
j->comline = cs = emalloc(comlen);
for (i = 0; argv[i]; i++) {
strcpy(cs, argv[i]);
if (argv[i + 1]) {
cs += strlen(argv[i]) + 1;
cs[-1] = ' ';
}
}
if (verbose > 0)
jail_note(j, "run command%s%s%s: %s\n",
injail ? " in jail" : "", username ? " as " : "",
username ? username : "", j->comline);
pid = fork();
if (pid < 0)
err(1, "fork");
if (pid > 0) {
if (bg) {
j->flags |= JF_BACKGROUND;
requeue(j, &ready);
} else {
--*plimit;
add_proc(j, pid);
}
return 1;
}
if (bg)
setsid();
pwd = NULL;
lcap = NULL;
if ((clean || username) && injail && sjuser &&
get_user_info(j, username, &pwd, &lcap) < 0)
exit(1);
if (injail) {
/* jail_attach won't chdir along with its chroot. */
path = string_param(j->intparams[KP_PATH]);
if (path && chdir(path) < 0) {
jail_warnx(j, "chdir %s: %s", path, strerror(errno));
exit(1);
}
if (int_param(j->intparams[IP_EXEC_FIB], &fib) &&
setfib(fib) < 0) {
jail_warnx(j, "setfib: %s", strerror(errno));
exit(1);
}
if (jail_attach(j->jid) < 0) {
jail_warnx(j, "jail_attach: %s", strerror(errno));
exit(1);
}
}
if (clean || username) {
if (!(injail && sjuser) &&
get_user_info(j, username, &pwd, &lcap) < 0)
exit(1);
if (clean) {
term = getenv("TERM");
environ = &cleanenv;
setenv("PATH", "/bin:/usr/bin", 0);
setenv("TERM", term, 1);
}
if (setusercontext(lcap, pwd, pwd->pw_uid, username
? LOGIN_SETALL & ~LOGIN_SETGROUP & ~LOGIN_SETLOGIN
: LOGIN_SETPATH | LOGIN_SETENV) < 0) {
jail_warnx(j, "setusercontext %s: %s", pwd->pw_name,
strerror(errno));
exit(1);
}
login_close(lcap);
setenv("USER", pwd->pw_name, 1);
setenv("HOME", pwd->pw_dir, 1);
setenv("SHELL",
*pwd->pw_shell ? pwd->pw_shell : _PATH_BSHELL, 1);
if (clean && chdir(pwd->pw_dir) < 0) {
jail_warnx(j, "chdir %s: %s",
pwd->pw_dir, strerror(errno));
exit(1);
}
endpwent();
}
if (consfd != 0 && (dup2(consfd, 1) < 0 || dup2(consfd, 2) < 0)) {
jail_warnx(j, "exec.consolelog: %s", strerror(errno));
exit(1);
}
closefrom(3);
execvp(argv[0], argv);
jail_warnx(j, "exec %s: %s", argv[0], strerror(errno));
exit(1);
}
/*
* Check command exit status
*/
int
finish_command(struct cfjail *j, int *plimit)
{
int error;
if (j->flags & (JF_RUNQ | JF_BACKGROUND))
return 0;
++*plimit;
if (!TAILQ_EMPTY(&runnable))
requeue(TAILQ_FIRST(&runnable), &ready);
error = 0;
if (j->flags & JF_TIMEOUT) {
j->flags &= ~JF_TIMEOUT;
if (j->comparam != IP_STOP_TIMEOUT) {
jail_warnx(j, "%s: timed out", j->comline);
failed(j);
error = -1;
} else if (verbose > 0)
jail_note(j, "timed out\n");
} else if (j->pstatus != 0) {
if (WIFSIGNALED(j->pstatus))
jail_warnx(j, "%s: exited on signal %d",
j->comline, WTERMSIG(j->pstatus));
else
jail_warnx(j, "%s: failed", j->comline);
failed(j);
error = -1;
}
free(j->comline);
return error;
}
/*
* Check for finished processed or timeouts.
*/
struct cfjail *
next_proc(int nonblock)
{
struct kevent ke;
struct timespec ts;
struct timespec *tsp;
struct cfjail *j;
if (!TAILQ_EMPTY(&sleeping)) {
again:
tsp = NULL;
if ((j = TAILQ_FIRST(&sleeping)) && j->timeout.tv_sec) {
clock_gettime(CLOCK_REALTIME, &ts);
ts.tv_sec = j->timeout.tv_sec - ts.tv_sec;
ts.tv_nsec = j->timeout.tv_nsec - ts.tv_nsec;
if (ts.tv_nsec < 0) {
ts.tv_sec--;
ts.tv_nsec += 1000000000;
}
if (ts.tv_sec < 0 ||
(ts.tv_sec == 0 && ts.tv_nsec == 0)) {
j->flags |= JF_TIMEOUT;
clear_procs(j);
return j;
}
tsp = &ts;
}
if (nonblock) {
ts.tv_sec = 0;
ts.tv_nsec = 0;
tsp = &ts;
}
switch (kevent(kq, NULL, 0, &ke, 1, tsp)) {
case -1:
if (errno != EINTR)
err(1, "kevent");
goto again;
case 0:
if (!nonblock) {
j = TAILQ_FIRST(&sleeping);
j->flags |= JF_TIMEOUT;
clear_procs(j);
return j;
}
break;
case 1:
(void)waitpid(ke.ident, NULL, WNOHANG);
if ((j = find_proc(ke.ident))) {
j->pstatus = ke.data;
return j;
}
goto again;
}
}
return NULL;
}
/*
* Send SIGTERM to all processes in a jail and wait for them to die.
*/
int
term_procs(struct cfjail *j)
{
struct kinfo_proc *ki;
int i, noted, pcnt, timeout;
static kvm_t *kd;
if (!int_param(j->intparams[IP_STOP_TIMEOUT], &timeout))
timeout = DEFAULT_STOP_TIMEOUT;
else if (timeout == 0)
return 0;
if (kd == NULL) {
kd = kvm_open(NULL, NULL, NULL, O_RDONLY, "jail");
if (kd == NULL)
exit(1);
}
ki = kvm_getprocs(kd, KERN_PROC_PROC, 0, &pcnt);
if (ki == NULL)
exit(1);
noted = 0;
for (i = 0; i < pcnt; i++)
if (ki[i].ki_jid == j->jid &&
kill(ki[i].ki_pid, SIGTERM) == 0) {
add_proc(j, ki[i].ki_pid);
if (verbose > 0) {
if (!noted) {
noted = 1;
jail_note(j, "sent SIGTERM to:");
}
printf(" %d", ki[i].ki_pid);
}
}
if (noted)
printf("\n");
if (j->nprocs > 0) {
clock_gettime(CLOCK_REALTIME, &j->timeout);
j->timeout.tv_sec += timeout;
return 1;
}
return 0;
}
/*
* Add a process to the hash, tied to a jail.
*/
static void
add_proc(struct cfjail *j, pid_t pid)
{
struct kevent ke;
struct cfjail *tj;
struct phash *ph;
if (!kq && (kq = kqueue()) < 0)
err(1, "kqueue");
EV_SET(&ke, pid, EVFILT_PROC, EV_ADD, NOTE_EXIT, 0, NULL);
if (kevent(kq, &ke, 1, NULL, 0, NULL) < 0)
err(1, "kevent");
ph = emalloc(sizeof(struct phash));
ph->j = j;
ph->pid = pid;
LIST_INSERT_HEAD(&phash[pid % PHASH_SIZE], ph, le);
j->nprocs++;
if (j->timeout.tv_sec) {
TAILQ_REMOVE(j->queue, j, tq);
TAILQ_FOREACH(tj, &sleeping, tq) {
if (!tj->timeout.tv_sec ||
j->timeout.tv_sec < tj->timeout.tv_sec ||
(j->timeout.tv_sec == tj->timeout.tv_sec &&
j->timeout.tv_nsec <= tj->timeout.tv_nsec)) {
TAILQ_INSERT_BEFORE(tj, j, tq);
break;
}
}
if (tj == NULL)
TAILQ_INSERT_TAIL(&sleeping, j, tq);
j->queue = &sleeping;
} else
requeue(j, &sleeping);
}
/*
* Remove any processes from the hash that correspond to a jail.
*/
static void
clear_procs(struct cfjail *j)
{
struct kevent ke;
struct phash *ph, *tph;
int i;
j->nprocs = 0;
for (i = 0; i < PHASH_SIZE; i++)
LIST_FOREACH_SAFE(ph, &phash[i], le, tph)
if (ph->j == j) {
EV_SET(&ke, ph->pid, EVFILT_PROC, EV_DELETE,
NOTE_EXIT, 0, NULL);
(void)kevent(kq, &ke, 1, NULL, 0, NULL);
LIST_REMOVE(ph, le);
free(ph);
}
}
/*
* Find the jail that corresponds to an exited process.
*/
static struct cfjail *
find_proc(pid_t pid)
{
struct cfjail *j;
struct phash *ph;
LIST_FOREACH(ph, &phash[pid % PHASH_SIZE], le)
if (ph->pid == pid) {
j = ph->j;
LIST_REMOVE(ph, le);
free(ph);
return --j->nprocs ? NULL : j;
}
return NULL;
}
/*
* Look up a user in the passwd and login.conf files.
*/
static int
get_user_info(struct cfjail *j, const char *username,
const struct passwd **pwdp, login_cap_t **lcapp)
{
const struct passwd *pwd;
*pwdp = pwd = username ? getpwnam(username) : getpwuid(getuid());
if (pwd == NULL) {
if (errno)
jail_warnx(j, "getpwnam%s%s: %s", username ? " " : "",
username ? username : "", strerror(errno));
else if (username)
jail_warnx(j, "%s: no such user", username);
else
jail_warnx(j, "unknown uid %d", getuid());
return -1;
}
*lcapp = login_getpwclass(pwd);
if (*lcapp == NULL) {
jail_warnx(j, "getpwclass %s: %s", pwd->pw_name,
strerror(errno));
return -1;
}
/* Set the groups while the group file is still available */
if (initgroups(pwd->pw_name, pwd->pw_gid) < 0) {
jail_warnx(j, "initgroups %s: %s", pwd->pw_name,
strerror(errno));
return -1;
}
return 0;
}
Check paths for security: path must be absolute. mount paths must exist and have no symlinks beyond the jail's path itself. consolelog must exist (apart from the final component) and have no symlinks beyond the jail's path itself.
2010-11-04 18:40:29 +00:00
/*
* Make sure a mount or consolelog path is a valid absolute pathname
* with no symlinks.
*/
static int
check_path(struct cfjail *j, const char *pname, const char *path, int isfile)
{
struct stat st;
char *tpath, *p;
const char *jailpath;
size_t jplen;
if (path[0] != '/') {
jail_warnx(j, "%s: %s: not an absolute pathname",
pname, path);
failed(j);
return -1;
}
/*
* Only check for symlinks in components below the jail's path,
* since that's where the security risk lies.
*/
jailpath = string_param(j->intparams[KP_PATH]);
if (jailpath == NULL)
jailpath = "";
jplen = strlen(jailpath);
if (strncmp(path, jailpath, jplen) || path[jplen] != '/')
return 0;
tpath = alloca(strlen(path) + 1);
strcpy(tpath, path);
for (p = tpath + jplen; p != NULL; ) {
p = strchr(p + 1, '/');
if (p)
*p = '\0';
if (lstat(tpath, &st) < 0) {
if (errno == ENOENT && isfile && !p)
break;
jail_warnx(j, "%s: %s: %s", pname, tpath,
strerror(errno));
failed(j);
return -1;
}
if (S_ISLNK(st.st_mode)) {
jail_warnx(j, "%s: %s is a symbolic link",
pname, tpath);
failed(j);
return -1;
}
if (p)
*p = '/';
}
return 0;
}
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