1
0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-23 11:18:54 +00:00
freebsd/sys/kern/kern_jail.c
Robert Drehmel ad1ff0997e Make getcredhostname() take a buffer and the buffer's size
as arguments.  The correct hostname is copied into the buffer
while having the prison's lock acquired in a jailed process'
case.

Reviewed by:	jhb, rwatson
2002-02-27 16:43:20 +00:00

260 lines
5.1 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
* ----------------------------------------------------------------------------
*
* $FreeBSD$
*
*/
#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/socket.h>
#include <sys/sysctl.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");
/*
* MPSAFE
*/
int
jail(td, uap)
struct thread *td;
struct jail_args /* {
syscallarg(struct jail *) jail;
} */ *uap;
{
struct proc *p = td->td_proc;
int error;
struct prison *pr;
struct jail j;
struct chroot_args ca;
struct ucred *newcred = NULL, *oldcred;
error = copyin(uap->jail, &j, sizeof j);
if (error)
return (error);
if (j.version != 0)
return (EINVAL);
mtx_lock(&Giant);
MALLOC(pr, struct prison *, sizeof *pr , M_PRISON, M_WAITOK | M_ZERO);
mtx_init(&pr->pr_mtx, "jail mutex", MTX_DEF);
pr->pr_securelevel = securelevel;
error = copyinstr(j.hostname, &pr->pr_host, sizeof pr->pr_host, 0);
if (error)
goto bail;
ca.path = j.path;
error = chroot(td, &ca);
if (error)
goto bail;
newcred = crget();
pr->pr_ip = j.ip_number;
PROC_LOCK(p);
/* Implicitly fail if already in jail. */
error = suser_xxx(p->p_ucred, NULL, 0);
if (error)
goto badcred;
oldcred = p->p_ucred;
crcopy(newcred, oldcred);
p->p_ucred = newcred;
p->p_ucred->cr_prison = pr;
pr->pr_ref = 1;
PROC_UNLOCK(p);
crfree(oldcred);
mtx_unlock(&Giant);
return (0);
badcred:
PROC_UNLOCK(p);
crfree(newcred);
bail:
FREE(pr, M_PRISON);
mtx_unlock(&Giant);
return (error);
}
void
prison_free(struct prison *pr)
{
mtx_lock(&pr->pr_mtx);
pr->pr_ref--;
if (pr->pr_ref == 0) {
mtx_unlock(&pr->pr_mtx);
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);
}
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 = (struct sockaddr_in*) sa;
int ok;
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(cred1, cred2)
struct ucred *cred1, *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(cred)
struct ucred *cred;
{
return (cred->cr_prison != NULL);
}
/*
* Return the correct hostname for the passed credential.
*/
void
getcredhostname(cred, buf, size)
struct ucred *cred;
char *buf;
size_t size;
{
if (jailed(cred)) {
mtx_lock(&cred->cr_prison->pr_mtx);
strncpy(buf, cred->cr_prison->pr_host, size);
mtx_unlock(&cred->cr_prison->pr_mtx);
}
else
strncpy(buf, hostname, size);
buf[size - 1] = '\0';
}