450 lines
9.3 KiB
C
450 lines
9.3 KiB
C
/*
|
|
* ----------------------------------------------------------------------------
|
|
* "THE BEER-WARE LICENSE" (Revision 42):
|
|
* <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you
|
|
* can do whatever you want with this stuff. If we meet some day, and you think
|
|
* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
|
|
* ----------------------------------------------------------------------------
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/types.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/errno.h>
|
|
#include <sys/sysproto.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/jail.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/namei.h>
|
|
#include <sys/queue.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/syscallsubr.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/vnode.h>
|
|
#include <net/if.h>
|
|
#include <netinet/in.h>
|
|
|
|
MALLOC_DEFINE(M_PRISON, "prison", "Prison structures");
|
|
|
|
SYSCTL_DECL(_security);
|
|
SYSCTL_NODE(_security, OID_AUTO, jail, CTLFLAG_RW, 0,
|
|
"Jail rules");
|
|
|
|
mp_fixme("these variables need a lock")
|
|
|
|
int jail_set_hostname_allowed = 1;
|
|
SYSCTL_INT(_security_jail, OID_AUTO, set_hostname_allowed, CTLFLAG_RW,
|
|
&jail_set_hostname_allowed, 0,
|
|
"Processes in jail can set their hostnames");
|
|
|
|
int jail_socket_unixiproute_only = 1;
|
|
SYSCTL_INT(_security_jail, OID_AUTO, socket_unixiproute_only, CTLFLAG_RW,
|
|
&jail_socket_unixiproute_only, 0,
|
|
"Processes in jail are limited to creating UNIX/IPv4/route sockets only");
|
|
|
|
int jail_sysvipc_allowed = 0;
|
|
SYSCTL_INT(_security_jail, OID_AUTO, sysvipc_allowed, CTLFLAG_RW,
|
|
&jail_sysvipc_allowed, 0,
|
|
"Processes in jail can use System V IPC primitives");
|
|
|
|
/* allprison, lastprid, and prisoncount are protected by allprison_mtx. */
|
|
struct prisonlist allprison;
|
|
struct mtx allprison_mtx;
|
|
int lastprid = 0;
|
|
int prisoncount = 0;
|
|
|
|
static void init_prison(void *);
|
|
static struct prison *prison_find(int);
|
|
static int sysctl_jail_list(SYSCTL_HANDLER_ARGS);
|
|
|
|
static void
|
|
init_prison(void *data __unused)
|
|
{
|
|
|
|
mtx_init(&allprison_mtx, "allprison", NULL, MTX_DEF);
|
|
LIST_INIT(&allprison);
|
|
}
|
|
|
|
SYSINIT(prison, SI_SUB_INTRINSIC, SI_ORDER_ANY, init_prison, NULL);
|
|
|
|
/*
|
|
* MPSAFE
|
|
*
|
|
* struct jail_args {
|
|
* struct jail *jail;
|
|
* };
|
|
*/
|
|
int
|
|
jail(struct thread *td, struct jail_args *uap)
|
|
{
|
|
struct nameidata nd;
|
|
struct prison *pr, *tpr;
|
|
struct jail j;
|
|
struct jail_attach_args jaa;
|
|
int error, tryprid;
|
|
|
|
error = copyin(uap->jail, &j, sizeof(j));
|
|
if (error)
|
|
return (error);
|
|
if (j.version != 0)
|
|
return (EINVAL);
|
|
|
|
MALLOC(pr, struct prison *, sizeof(*pr), M_PRISON, M_WAITOK | M_ZERO);
|
|
mtx_init(&pr->pr_mtx, "jail mutex", NULL, MTX_DEF);
|
|
pr->pr_ref = 1;
|
|
error = copyinstr(j.path, &pr->pr_path, sizeof(pr->pr_path), 0);
|
|
if (error)
|
|
goto e_killmtx;
|
|
mtx_lock(&Giant);
|
|
NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, pr->pr_path, td);
|
|
error = namei(&nd);
|
|
if (error) {
|
|
mtx_unlock(&Giant);
|
|
goto e_killmtx;
|
|
}
|
|
pr->pr_root = nd.ni_vp;
|
|
VOP_UNLOCK(nd.ni_vp, 0, td);
|
|
NDFREE(&nd, NDF_ONLY_PNBUF);
|
|
mtx_unlock(&Giant);
|
|
error = copyinstr(j.hostname, &pr->pr_host, sizeof(pr->pr_host), 0);
|
|
if (error)
|
|
goto e_dropvnref;
|
|
pr->pr_ip = j.ip_number;
|
|
pr->pr_linux = NULL;
|
|
pr->pr_securelevel = securelevel;
|
|
|
|
/* Determine next pr_id and add prison to allprison list. */
|
|
mtx_lock(&allprison_mtx);
|
|
tryprid = lastprid + 1;
|
|
if (tryprid == JAIL_MAX)
|
|
tryprid = 1;
|
|
next:
|
|
LIST_FOREACH(tpr, &allprison, pr_list) {
|
|
if (tpr->pr_id == tryprid) {
|
|
tryprid++;
|
|
if (tryprid == JAIL_MAX) {
|
|
mtx_unlock(&allprison_mtx);
|
|
error = EAGAIN;
|
|
goto e_dropvnref;
|
|
}
|
|
goto next;
|
|
}
|
|
}
|
|
pr->pr_id = jaa.jid = lastprid = tryprid;
|
|
LIST_INSERT_HEAD(&allprison, pr, pr_list);
|
|
prisoncount++;
|
|
mtx_unlock(&allprison_mtx);
|
|
|
|
error = jail_attach(td, &jaa);
|
|
if (error)
|
|
goto e_dropprref;
|
|
mtx_lock(&pr->pr_mtx);
|
|
pr->pr_ref--;
|
|
mtx_unlock(&pr->pr_mtx);
|
|
td->td_retval[0] = jaa.jid;
|
|
return (0);
|
|
e_dropprref:
|
|
mtx_lock(&allprison_mtx);
|
|
LIST_REMOVE(pr, pr_list);
|
|
prisoncount--;
|
|
mtx_unlock(&allprison_mtx);
|
|
e_dropvnref:
|
|
mtx_lock(&Giant);
|
|
vrele(pr->pr_root);
|
|
mtx_unlock(&Giant);
|
|
e_killmtx:
|
|
mtx_destroy(&pr->pr_mtx);
|
|
FREE(pr, M_PRISON);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* MPSAFE
|
|
*
|
|
* struct jail_attach_args {
|
|
* int jid;
|
|
* };
|
|
*/
|
|
int
|
|
jail_attach(struct thread *td, struct jail_attach_args *uap)
|
|
{
|
|
struct proc *p;
|
|
struct ucred *newcred, *oldcred;
|
|
struct prison *pr;
|
|
int error;
|
|
|
|
p = td->td_proc;
|
|
|
|
mtx_lock(&allprison_mtx);
|
|
pr = prison_find(uap->jid);
|
|
if (pr == NULL) {
|
|
mtx_unlock(&allprison_mtx);
|
|
return (EINVAL);
|
|
}
|
|
pr->pr_ref++;
|
|
mtx_unlock(&pr->pr_mtx);
|
|
mtx_unlock(&allprison_mtx);
|
|
|
|
error = suser_cred(td->td_ucred, PRISON_ROOT);
|
|
if (error)
|
|
goto e_dropref;
|
|
mtx_lock(&Giant);
|
|
vn_lock(pr->pr_root, LK_EXCLUSIVE | LK_RETRY, td);
|
|
if ((error = change_dir(pr->pr_root, td)) != 0)
|
|
goto e_unlock;
|
|
#ifdef MAC
|
|
if ((error = mac_check_vnode_chroot(td->td_ucred, pr->pr_root)))
|
|
goto e_unlock;
|
|
#endif
|
|
VOP_UNLOCK(pr->pr_root, 0, td);
|
|
change_root(pr->pr_root, td);
|
|
mtx_unlock(&Giant);
|
|
|
|
newcred = crget();
|
|
PROC_LOCK(p);
|
|
/* Implicitly fail if already in jail. */
|
|
error = suser_cred(p->p_ucred, 0);
|
|
if (error) {
|
|
PROC_UNLOCK(p);
|
|
crfree(newcred);
|
|
goto e_dropref;
|
|
}
|
|
oldcred = p->p_ucred;
|
|
setsugid(p);
|
|
crcopy(newcred, oldcred);
|
|
newcred->cr_prison = pr;
|
|
p->p_ucred = newcred;
|
|
PROC_UNLOCK(p);
|
|
crfree(oldcred);
|
|
return (0);
|
|
e_unlock:
|
|
VOP_UNLOCK(pr->pr_root, 0, td);
|
|
mtx_unlock(&Giant);
|
|
e_dropref:
|
|
mtx_lock(&pr->pr_mtx);
|
|
pr->pr_ref--;
|
|
mtx_unlock(&pr->pr_mtx);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Returns a locked prison instance, or NULL on failure.
|
|
*/
|
|
static struct prison *
|
|
prison_find(int prid)
|
|
{
|
|
struct prison *pr;
|
|
|
|
mtx_assert(&allprison_mtx, MA_OWNED);
|
|
LIST_FOREACH(pr, &allprison, pr_list) {
|
|
if (pr->pr_id == prid) {
|
|
mtx_lock(&pr->pr_mtx);
|
|
return (pr);
|
|
}
|
|
}
|
|
return (NULL);
|
|
}
|
|
|
|
void
|
|
prison_free(struct prison *pr)
|
|
{
|
|
|
|
mtx_assert(&Giant, MA_OWNED);
|
|
mtx_lock(&allprison_mtx);
|
|
mtx_lock(&pr->pr_mtx);
|
|
pr->pr_ref--;
|
|
if (pr->pr_ref == 0) {
|
|
LIST_REMOVE(pr, pr_list);
|
|
mtx_unlock(&pr->pr_mtx);
|
|
prisoncount--;
|
|
mtx_unlock(&allprison_mtx);
|
|
vrele(pr->pr_root);
|
|
mtx_destroy(&pr->pr_mtx);
|
|
if (pr->pr_linux != NULL)
|
|
FREE(pr->pr_linux, M_PRISON);
|
|
FREE(pr, M_PRISON);
|
|
return;
|
|
}
|
|
mtx_unlock(&pr->pr_mtx);
|
|
mtx_unlock(&allprison_mtx);
|
|
}
|
|
|
|
void
|
|
prison_hold(struct prison *pr)
|
|
{
|
|
|
|
mtx_lock(&pr->pr_mtx);
|
|
pr->pr_ref++;
|
|
mtx_unlock(&pr->pr_mtx);
|
|
}
|
|
|
|
u_int32_t
|
|
prison_getip(struct ucred *cred)
|
|
{
|
|
|
|
return (cred->cr_prison->pr_ip);
|
|
}
|
|
|
|
int
|
|
prison_ip(struct ucred *cred, int flag, u_int32_t *ip)
|
|
{
|
|
u_int32_t tmp;
|
|
|
|
if (!jailed(cred))
|
|
return (0);
|
|
if (flag)
|
|
tmp = *ip;
|
|
else
|
|
tmp = ntohl(*ip);
|
|
if (tmp == INADDR_ANY) {
|
|
if (flag)
|
|
*ip = cred->cr_prison->pr_ip;
|
|
else
|
|
*ip = htonl(cred->cr_prison->pr_ip);
|
|
return (0);
|
|
}
|
|
if (tmp == INADDR_LOOPBACK) {
|
|
if (flag)
|
|
*ip = cred->cr_prison->pr_ip;
|
|
else
|
|
*ip = htonl(cred->cr_prison->pr_ip);
|
|
return (0);
|
|
}
|
|
if (cred->cr_prison->pr_ip != tmp)
|
|
return (1);
|
|
return (0);
|
|
}
|
|
|
|
void
|
|
prison_remote_ip(struct ucred *cred, int flag, u_int32_t *ip)
|
|
{
|
|
u_int32_t tmp;
|
|
|
|
if (!jailed(cred))
|
|
return;
|
|
if (flag)
|
|
tmp = *ip;
|
|
else
|
|
tmp = ntohl(*ip);
|
|
if (tmp == INADDR_LOOPBACK) {
|
|
if (flag)
|
|
*ip = cred->cr_prison->pr_ip;
|
|
else
|
|
*ip = htonl(cred->cr_prison->pr_ip);
|
|
return;
|
|
}
|
|
return;
|
|
}
|
|
|
|
int
|
|
prison_if(struct ucred *cred, struct sockaddr *sa)
|
|
{
|
|
struct sockaddr_in *sai;
|
|
int ok;
|
|
|
|
sai = (struct sockaddr_in *)sa;
|
|
if ((sai->sin_family != AF_INET) && jail_socket_unixiproute_only)
|
|
ok = 1;
|
|
else if (sai->sin_family != AF_INET)
|
|
ok = 0;
|
|
else if (cred->cr_prison->pr_ip != ntohl(sai->sin_addr.s_addr))
|
|
ok = 1;
|
|
else
|
|
ok = 0;
|
|
return (ok);
|
|
}
|
|
|
|
/*
|
|
* Return 0 if jails permit p1 to frob p2, otherwise ESRCH.
|
|
*/
|
|
int
|
|
prison_check(struct ucred *cred1, struct ucred *cred2)
|
|
{
|
|
|
|
if (jailed(cred1)) {
|
|
if (!jailed(cred2))
|
|
return (ESRCH);
|
|
if (cred2->cr_prison != cred1->cr_prison)
|
|
return (ESRCH);
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Return 1 if the passed credential is in a jail, otherwise 0.
|
|
*/
|
|
int
|
|
jailed(struct ucred *cred)
|
|
{
|
|
|
|
return (cred->cr_prison != NULL);
|
|
}
|
|
|
|
/*
|
|
* Return the correct hostname for the passed credential.
|
|
*/
|
|
void
|
|
getcredhostname(struct ucred *cred, char *buf, size_t size)
|
|
{
|
|
|
|
if (jailed(cred)) {
|
|
mtx_lock(&cred->cr_prison->pr_mtx);
|
|
strlcpy(buf, cred->cr_prison->pr_host, size);
|
|
mtx_unlock(&cred->cr_prison->pr_mtx);
|
|
} else
|
|
strlcpy(buf, hostname, size);
|
|
}
|
|
|
|
static int
|
|
sysctl_jail_list(SYSCTL_HANDLER_ARGS)
|
|
{
|
|
struct xprison *xp, *sxp;
|
|
struct prison *pr;
|
|
int count, error;
|
|
|
|
mtx_assert(&Giant, MA_OWNED);
|
|
retry:
|
|
mtx_lock(&allprison_mtx);
|
|
count = prisoncount;
|
|
mtx_unlock(&allprison_mtx);
|
|
|
|
if (count == 0)
|
|
return (0);
|
|
|
|
sxp = xp = malloc(sizeof(*xp) * count, M_TEMP, M_WAITOK | M_ZERO);
|
|
mtx_lock(&allprison_mtx);
|
|
if (count != prisoncount) {
|
|
mtx_unlock(&allprison_mtx);
|
|
free(sxp, M_TEMP);
|
|
goto retry;
|
|
}
|
|
|
|
LIST_FOREACH(pr, &allprison, pr_list) {
|
|
mtx_lock(&pr->pr_mtx);
|
|
xp->pr_version = XPRISON_VERSION;
|
|
xp->pr_id = pr->pr_id;
|
|
strlcpy(xp->pr_path, pr->pr_path, sizeof(xp->pr_path));
|
|
strlcpy(xp->pr_host, pr->pr_host, sizeof(xp->pr_host));
|
|
xp->pr_ip = pr->pr_ip;
|
|
mtx_unlock(&pr->pr_mtx);
|
|
xp++;
|
|
}
|
|
mtx_unlock(&allprison_mtx);
|
|
|
|
error = SYSCTL_OUT(req, sxp, sizeof(*sxp) * count);
|
|
free(sxp, M_TEMP);
|
|
if (error)
|
|
return (error);
|
|
return (0);
|
|
}
|
|
|
|
SYSCTL_OID(_security_jail, OID_AUTO, list, CTLTYPE_STRUCT | CTLFLAG_RD,
|
|
NULL, 0, sysctl_jail_list, "S", "List of active jails");
|