policy.c revision da14cebe459d3275048785f25bd869cb09b5307f
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include <sys/types.h>
#include <sys/sysmacros.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/cred_impl.h>
#include <sys/vnode.h>
#include <sys/vfs.h>
#include <sys/stat.h>
#include <sys/errno.h>
#include <sys/kmem.h>
#include <sys/user.h>
#include <sys/proc.h>
#include <sys/acct.h>
#include <sys/ipc_impl.h>
#include <sys/cmn_err.h>
#include <sys/debug.h>
#include <sys/policy.h>
#include <sys/kobj.h>
#include <sys/msg.h>
#include <sys/devpolicy.h>
#include <c2/audit.h>
#include <sys/varargs.h>
#include <sys/klpd.h>
#include <sys/modctl.h>
#include <sys/disp.h>
#include <sys/zone.h>
#include <inet/optcom.h>
#include <sys/sdt.h>
#include <sys/vfs.h>
#include <sys/mntent.h>
#include <sys/contract_impl.h>
#include <sys/dld_ioc.h>
/*
* There are two possible layers of privilege routines and two possible
* levels of secpolicy. Plus one other we may not be interested in, so
* we may need as many as 6 but no more.
*/
#define MAXPRIVSTACK 6
int priv_debug = 0;
/*
* This file contains the majority of the policy routines.
* Since the policy routines are defined by function and not
* by privilege, there is quite a bit of duplication of
* functions.
*
* The secpolicy functions must not make assumptions about
* locks held or not held as any lock can be held while they're
* being called.
*
* Credentials are read-only so no special precautions need to
* be taken while locking them.
*
* When a new policy check needs to be added to the system the
* following procedure should be followed:
*
* Pick an appropriate secpolicy_*() function
* -> done if one exists.
* Create a new secpolicy function, preferably with
* a descriptive name using the standard template.
* Pick an appropriate privilege for the policy.
* If no appropraite privilege exists, define new one
* (this should be done with extreme care; in most cases
* little is gained by adding another privilege)
*
* WHY ROOT IS STILL SPECIAL.
*
* In a number of the policy functions, there are still explicit
* checks for uid 0. The rationale behind these is that many root
* owned files/objects hold configuration information which can give full
* privileges to the user once written to. To prevent escalation
* of privilege by allowing just a single privilege to modify root owned
* objects, we've added these root specific checks where we considered
* them necessary: modifying root owned files, changing uids to 0, etc.
*
* PRIVILEGE ESCALATION AND ZONES.
*
* A number of operations potentially allow the caller to achieve
* privileges beyond the ones normally required to perform the operation.
* For example, if allowed to create a setuid 0 executable, a process can
* gain privileges beyond PRIV_FILE_SETID. Zones, however, place
* restrictions on the ability to gain privileges beyond those available
* within the zone through file and process manipulation. Hence, such
* operations require that the caller have an effective set that includes
* all privileges available within the current zone, or all privileges
* if executing in the global zone.
*
* This is indicated in the priv_policy* policy checking functions
* through a combination of parameters. The "priv" parameter indicates
* the privilege that is required, and the "allzone" parameter indicates
* whether or not all privileges in the zone are required. In addition,
* priv can be set to PRIV_ALL to indicate that all privileges are
* required (regardless of zone). There are three scenarios of interest:
* (1) operation requires a specific privilege
* (2) operation requires a specific privilege, and requires all
* privileges available within the zone (or all privileges if in
* the global zone)
* (3) operation requires all privileges, regardless of zone
*
* For (1), priv should be set to the specific privilege, and allzone
* should be set to B_FALSE.
* For (2), priv should be set to the specific privilege, and allzone
* should be set to B_TRUE.
* For (3), priv should be set to PRIV_ALL, and allzone should be set
* to B_FALSE.
*
*/
/*
* The privileges are checked against the Effective set for
* ordinary processes and checked against the Limit set
* for euid 0 processes that haven't manipulated their privilege
* sets.
*/
#define HAS_ALLPRIVS(cr) priv_isfullset(&CR_OEPRIV(cr))
#define ZONEPRIVS(cr) ((cr)->cr_zone->zone_privset)
#define HAS_ALLZONEPRIVS(cr) priv_issubset(ZONEPRIVS(cr), &CR_OEPRIV(cr))
#define HAS_PRIVILEGE(cr, pr) ((pr) == PRIV_ALL ? \
HAS_ALLPRIVS(cr) : \
PRIV_ISASSERT(&CR_OEPRIV(cr), pr))
/*
* Policy checking functions.
*
* All of the system's policy should be implemented here.
*/
/*
* Private functions which take an additional va_list argument to
* implement an object specific policy override.
*/
static int priv_policy_ap(const cred_t *, int, boolean_t, int,
const char *, va_list);
static int priv_policy_va(const cred_t *, int, boolean_t, int,
const char *, ...);
/*
* Generic policy calls
*
* The "bottom" functions of policy control
*/
static char *
mprintf(const char *fmt, ...)
{
va_list args;
char *buf;
size_t len;
va_start(args, fmt);
len = vsnprintf(NULL, 0, fmt, args) + 1;
va_end(args);
buf = kmem_alloc(len, KM_NOSLEEP);
if (buf == NULL)
return (NULL);
va_start(args, fmt);
(void) vsnprintf(buf, len, fmt, args);
va_end(args);
return (buf);
}
/*
* priv_policy_errmsg()
*
* Generate an error message if privilege debugging is enabled system wide
* or for this particular process.
*/
#define FMTHDR "%s[%d]: missing privilege \"%s\" (euid = %d, syscall = %d)"
#define FMTMSG " for \"%s\""
#define FMTFUN " needed at %s+0x%lx"
/* The maximum size privilege format: the concatenation of the above */
#define FMTMAX FMTHDR FMTMSG FMTFUN "\n"
static void
priv_policy_errmsg(const cred_t *cr, int priv, const char *msg)
{
struct proc *me;
pc_t stack[MAXPRIVSTACK];
int depth;
int i;
char *sym;
ulong_t off;
const char *pname;
char *cmd;
char fmt[sizeof (FMTMAX)];
if ((me = curproc) == &p0)
return;
/* Privileges must be defined */
ASSERT(priv == PRIV_ALL || priv == PRIV_MULTIPLE ||
priv == PRIV_ALLZONE || priv == PRIV_GLOBAL ||
priv_getbynum(priv) != NULL);
if (priv == PRIV_ALLZONE && INGLOBALZONE(me))
priv = PRIV_ALL;
if (curthread->t_pre_sys)
ttolwp(curthread)->lwp_badpriv = (short)priv;
if (priv_debug == 0 && (CR_FLAGS(cr) & PRIV_DEBUG) == 0)
return;
(void) strcpy(fmt, FMTHDR);
if (me->p_user.u_comm[0])
cmd = &me->p_user.u_comm[0];
else
cmd = "priv_policy";
if (msg != NULL && *msg != '\0') {
(void) strcat(fmt, FMTMSG);
} else {
(void) strcat(fmt, "%s");
msg = "";
}
sym = NULL;
depth = getpcstack(stack, MAXPRIVSTACK);
/*
* Try to find the first interesting function on the stack.
* priv_policy* that's us, so completely uninteresting.
* suser(), drv_priv(), secpolicy_* are also called from
* too many locations to convey useful information.
*/
for (i = 0; i < depth; i++) {
sym = kobj_getsymname((uintptr_t)stack[i], &off);
if (sym != NULL &&
strstr(sym, "hasprocperm") == 0 &&
strcmp("suser", sym) != 0 &&
strcmp("ipcaccess", sym) != 0 &&
strcmp("drv_priv", sym) != 0 &&
strncmp("secpolicy_", sym, 10) != 0 &&
strncmp("priv_policy", sym, 11) != 0)
break;
}
if (sym != NULL)
(void) strcat(fmt, FMTFUN);
(void) strcat(fmt, "\n");
switch (priv) {
case PRIV_ALL:
pname = "ALL";
break;
case PRIV_MULTIPLE:
pname = "MULTIPLE";
break;
case PRIV_ALLZONE:
pname = "ZONE";
break;
case PRIV_GLOBAL:
pname = "GLOBAL";
break;
default:
pname = priv_getbynum(priv);
break;
}
if (CR_FLAGS(cr) & PRIV_DEBUG) {
/* Remember last message, just like lwp_badpriv. */
if (curthread->t_pdmsg != NULL) {
kmem_free(curthread->t_pdmsg,
strlen(curthread->t_pdmsg) + 1);
}
curthread->t_pdmsg = mprintf(fmt, cmd, me->p_pid, pname,
cr->cr_uid, curthread->t_sysnum, msg, sym, off);
curthread->t_post_sys = 1;
}
if (priv_debug) {
cmn_err(CE_NOTE, fmt, cmd, me->p_pid, pname, cr->cr_uid,
curthread->t_sysnum, msg, sym, off);
}
}
/*
* Override the policy, if appropriate. Return 0 if the external
* policy engine approves.
*/
static int
priv_policy_override(const cred_t *cr, int priv, boolean_t allzone, va_list ap)
{
priv_set_t set;
int ret;
if (!(CR_FLAGS(cr) & PRIV_XPOLICY))
return (-1);
if (priv == PRIV_ALL) {
priv_fillset(&set);
} else if (allzone) {
set = *ZONEPRIVS(cr);
} else {
priv_emptyset(&set);
priv_addset(&set, priv);
}
ret = klpd_call(cr, &set, ap);
return (ret);
}
static int
priv_policy_override_set(const cred_t *cr, const priv_set_t *req, ...)
{
va_list ap;
if (CR_FLAGS(cr) & PRIV_XPOLICY) {
va_start(ap, req);
return (klpd_call(cr, req, ap));
}
return (-1);
}
/*
* Audit failure, log error message.
*/
static void
priv_policy_err(const cred_t *cr, int priv, boolean_t allzone, const char *msg)
{
if (audit_active)
audit_priv(priv, allzone ? ZONEPRIVS(cr) : NULL, 0);
DTRACE_PROBE2(priv__err, int, priv, boolean_t, allzone);
if (priv_debug || (CR_FLAGS(cr) & PRIV_DEBUG) ||
curthread->t_pre_sys) {
if (allzone && !HAS_ALLZONEPRIVS(cr)) {
priv_policy_errmsg(cr, PRIV_ALLZONE, msg);
} else {
ASSERT(!HAS_PRIVILEGE(cr, priv));
priv_policy_errmsg(cr, priv, msg);
}
}
}
/*
* priv_policy_ap()
* return 0 or error.
* See block comment above for a description of "priv" and "allzone" usage.
*/
static int
priv_policy_ap(const cred_t *cr, int priv, boolean_t allzone, int err,
const char *msg, va_list ap)
{
if ((HAS_PRIVILEGE(cr, priv) && (!allzone || HAS_ALLZONEPRIVS(cr))) ||
(!servicing_interrupt() &&
priv_policy_override(cr, priv, allzone, ap) == 0)) {
if ((allzone || priv == PRIV_ALL ||
!PRIV_ISASSERT(priv_basic, priv)) &&
!servicing_interrupt()) {
PTOU(curproc)->u_acflag |= ASU; /* Needed for SVVS */
if (audit_active)
audit_priv(priv,
allzone ? ZONEPRIVS(cr) : NULL, 1);
}
err = 0;
DTRACE_PROBE2(priv__ok, int, priv, boolean_t, allzone);
} else if (!servicing_interrupt()) {
/* Failure audited in this procedure */
priv_policy_err(cr, priv, allzone, msg);
}
return (err);
}
int
priv_policy_va(const cred_t *cr, int priv, boolean_t allzone, int err,
const char *msg, ...)
{
int ret;
va_list ap;
va_start(ap, msg);
ret = priv_policy_ap(cr, priv, allzone, err, msg, ap);
va_end(ap);
return (ret);
}
int
priv_policy(const cred_t *cr, int priv, boolean_t allzone, int err,
const char *msg)
{
return (priv_policy_va(cr, priv, allzone, err, msg, KLPDARG_NOMORE));
}
/*
* Return B_TRUE for sufficient privileges, B_FALSE for insufficient privileges.
*/
boolean_t
priv_policy_choice(const cred_t *cr, int priv, boolean_t allzone)
{
boolean_t res = HAS_PRIVILEGE(cr, priv) &&
(!allzone || HAS_ALLZONEPRIVS(cr));
/* Audit success only */
if (res && audit_active &&
(allzone || priv == PRIV_ALL || !PRIV_ISASSERT(priv_basic, priv)) &&
!servicing_interrupt()) {
audit_priv(priv, allzone ? ZONEPRIVS(cr) : NULL, 1);
}
if (res) {
DTRACE_PROBE2(priv__ok, int, priv, boolean_t, allzone);
} else {
DTRACE_PROBE2(priv__err, int, priv, boolean_t, allzone);
}
return (res);
}
/*
* Non-auditing variant of priv_policy_choice().
*/
boolean_t
priv_policy_only(const cred_t *cr, int priv, boolean_t allzone)
{
boolean_t res = HAS_PRIVILEGE(cr, priv) &&
(!allzone || HAS_ALLZONEPRIVS(cr));
if (res) {
DTRACE_PROBE2(priv__ok, int, priv, boolean_t, allzone);
} else {
DTRACE_PROBE2(priv__err, int, priv, boolean_t, allzone);
}
return (res);
}
/*
* Check whether all privileges in the required set are present.
*/
static int
secpolicy_require_set(const cred_t *cr, const priv_set_t *req, const char *msg)
{
int priv;
int pfound = -1;
priv_set_t pset;
if (req == PRIV_FULLSET ? HAS_ALLPRIVS(cr) : priv_issubset(req,
&CR_OEPRIV(cr))) {
return (0);
}
if (priv_policy_override_set(cr, req, KLPDARG_NOMORE) == 0)
return (0);
if (req == PRIV_FULLSET || priv_isfullset(req)) {
priv_policy_err(cr, PRIV_ALL, B_FALSE, msg);
return (EACCES);
}
pset = CR_OEPRIV(cr); /* present privileges */
priv_inverse(&pset); /* all non present privileges */
priv_intersect(req, &pset); /* the actual missing privs */
if (audit_active)
audit_priv(PRIV_NONE, &pset, 0);
/*
* Privilege debugging; special case "one privilege in set".
*/
if (priv_debug || (CR_FLAGS(cr) & PRIV_DEBUG) || curthread->t_pre_sys) {
for (priv = 0; priv < nprivs; priv++) {
if (priv_ismember(&pset, priv)) {
if (pfound != -1) {
/* Multiple missing privs */
priv_policy_errmsg(cr, PRIV_MULTIPLE,
msg);
return (EACCES);
}
pfound = priv;
}
}
ASSERT(pfound != -1);
/* Just the one missing privilege */
priv_policy_errmsg(cr, pfound, msg);
}
return (EACCES);
}
/*
* Called when an operation requires that the caller be in the
* global zone, regardless of privilege.
*/
static int
priv_policy_global(const cred_t *cr)
{
if (crgetzoneid(cr) == GLOBAL_ZONEID)
return (0); /* success */
if (priv_debug || (CR_FLAGS(cr) & PRIV_DEBUG) ||
curthread->t_pre_sys) {
priv_policy_errmsg(cr, PRIV_GLOBAL, NULL);
}
return (EPERM);
}
/*
* Changing process priority
*/
int
secpolicy_setpriority(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_PROC_PRIOCNTL, B_FALSE, EPERM, NULL));
}
/*
* Binding to a privileged port, port must be specified in host byte
* order.
*/
int
secpolicy_net_privaddr(const cred_t *cr, in_port_t port, int proto)
{
char *reason;
int priv;
switch (port) {
case 137:
case 138:
case 139:
case 445:
/*
* NBT and SMB ports, these are extra privileged ports,
* allow bind only if the SYS_SMB privilege is present.
*/
priv = PRIV_SYS_SMB;
reason = "NBT or SMB port";
break;
case 2049:
case 4045:
/*
* NFS ports, these are extra privileged ports, allow bind
* only if the SYS_NFS privilege is present.
*/
priv = PRIV_SYS_NFS;
reason = "NFS port";
break;
default:
priv = PRIV_NET_PRIVADDR;
reason = NULL;
break;
}
return (priv_policy_va(cr, priv, B_FALSE, EACCES, reason,
KLPDARG_PORT, (int)proto, (int)port, KLPDARG_NOMORE));
}
/*
* Binding to a multilevel port on a trusted (labeled) system.
*/
int
secpolicy_net_bindmlp(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_NET_BINDMLP, B_FALSE, EACCES, NULL));
}
/*
* Allow a communication between a zone and an unlabeled host when their
* labels don't match.
*/
int
secpolicy_net_mac_aware(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_NET_MAC_AWARE, B_FALSE, EACCES, NULL));
}
/*
* Common routine which determines whether a given credential can
* act on a given mount.
* When called through mount, the parameter needoptcheck is a pointer
* to a boolean variable which will be set to either true or false,
* depending on whether the mount policy should change the mount options.
* In all other cases, needoptcheck should be a NULL pointer.
*/
static int
secpolicy_fs_common(cred_t *cr, vnode_t *mvp, const vfs_t *vfsp,
boolean_t *needoptcheck)
{
boolean_t allzone = B_FALSE;
boolean_t mounting = needoptcheck != NULL;
/*
* Short circuit the following cases:
* vfsp == NULL or mvp == NULL (pure privilege check)
* have all privileges - no further checks required
* and no mount options need to be set.
*/
if (vfsp == NULL || mvp == NULL || HAS_ALLPRIVS(cr)) {
if (mounting)
*needoptcheck = B_FALSE;
return (priv_policy_va(cr, PRIV_SYS_MOUNT, allzone, EPERM,
NULL, KLPDARG_VNODE, mvp, (char *)NULL, KLPDARG_NOMORE));
}
/*
* When operating on an existing mount (either we're not mounting
* or we're doing a remount and VFS_REMOUNT will be set), zones
* can operate only on mounts established by the zone itself.
*/
if (!mounting || (vfsp->vfs_flag & VFS_REMOUNT) != 0) {
zoneid_t zoneid = crgetzoneid(cr);
if (zoneid != GLOBAL_ZONEID &&
vfsp->vfs_zone->zone_id != zoneid) {
return (EPERM);
}
}
if (mounting)
*needoptcheck = B_TRUE;
/*
* Overlay mounts may hide important stuff; if you can't write to a
* mount point but would be able to mount on top of it, you can
* escalate your privileges.
* So we go about asking the same questions namefs does when it
* decides whether you can mount over a file or not but with the
* added restriction that you can only mount on top of a regular
* file or directory.
* If we have all the zone's privileges, we skip all other checks,
* or else we may actually get in trouble inside the automounter.
*/
if ((mvp->v_flag & VROOT) != 0 ||
(mvp->v_type != VDIR && mvp->v_type != VREG) ||
HAS_ALLZONEPRIVS(cr)) {
allzone = B_TRUE;
} else {
vattr_t va;
int err;
va.va_mask = AT_UID|AT_MODE;
err = VOP_GETATTR(mvp, &va, 0, cr, NULL);
if (err != 0)
return (err);
if ((err = secpolicy_vnode_owner(cr, va.va_uid)) != 0)
return (err);
if ((va.va_mode & VWRITE) == 0 &&
secpolicy_vnode_access(cr, mvp, va.va_uid, VWRITE) != 0) {
return (EACCES);
}
}
return (priv_policy_va(cr, PRIV_SYS_MOUNT, allzone, EPERM,
NULL, KLPDARG_VNODE, mvp, (char *)NULL, KLPDARG_NOMORE));
}
void
secpolicy_fs_mount_clearopts(cred_t *cr, struct vfs *vfsp)
{
boolean_t amsuper = HAS_ALLZONEPRIVS(cr);
/*
* check; if we don't have either "nosuid" or
* both "nosetuid" and "nodevices", then we add
* "nosuid"; this depends on how the current
* implementation works (it first checks nosuid). In a
* zone, a user with all zone privileges can mount with
* "setuid" but never with "devices".
*/
if (!vfs_optionisset(vfsp, MNTOPT_NOSUID, NULL) &&
(!vfs_optionisset(vfsp, MNTOPT_NODEVICES, NULL) ||
!vfs_optionisset(vfsp, MNTOPT_NOSETUID, NULL))) {
if (crgetzoneid(cr) == GLOBAL_ZONEID || !amsuper)
vfs_setmntopt(vfsp, MNTOPT_NOSUID, NULL, 0);
else
vfs_setmntopt(vfsp, MNTOPT_NODEVICES, NULL, 0);
}
/*
* If we're not the local super user, we set the "restrict"
* option to indicate to automountd that this mount should
* be handled with care.
*/
if (!amsuper)
vfs_setmntopt(vfsp, MNTOPT_RESTRICT, NULL, 0);
}
extern vnode_t *rootvp;
extern vfs_t *rootvfs;
int
secpolicy_fs_mount(cred_t *cr, vnode_t *mvp, struct vfs *vfsp)
{
boolean_t needoptchk;
int error;
/*
* If it's a remount, get the underlying mount point,
* except for the root where we use the rootvp.
*/
if ((vfsp->vfs_flag & VFS_REMOUNT) != 0) {
if (vfsp == rootvfs)
mvp = rootvp;
else
mvp = vfsp->vfs_vnodecovered;
}
error = secpolicy_fs_common(cr, mvp, vfsp, &needoptchk);
if (error == 0 && needoptchk) {
secpolicy_fs_mount_clearopts(cr, vfsp);
}
return (error);
}
/*
* Does the policy computations for "ownership" of a mount;
* here ownership is defined as the ability to "mount"
* the filesystem originally. The rootvfs doesn't cover any
* vnodes; we attribute its ownership to the rootvp.
*/
static int
secpolicy_fs_owner(cred_t *cr, const struct vfs *vfsp)
{
vnode_t *mvp;
if (vfsp == NULL)
mvp = NULL;
else if (vfsp == rootvfs)
mvp = rootvp;
else
mvp = vfsp->vfs_vnodecovered;
return (secpolicy_fs_common(cr, mvp, vfsp, NULL));
}
int
secpolicy_fs_unmount(cred_t *cr, struct vfs *vfsp)
{
return (secpolicy_fs_owner(cr, vfsp));
}
/*
* Quotas are a resource, but if one has the ability to mount a filesystem, he
* should be able to modify quotas on it.
*/
int
secpolicy_fs_quota(const cred_t *cr, const vfs_t *vfsp)
{
return (secpolicy_fs_owner((cred_t *)cr, vfsp));
}
/*
* Exceeding minfree: also a per-mount resource constraint.
*/
int
secpolicy_fs_minfree(const cred_t *cr, const vfs_t *vfsp)
{
return (secpolicy_fs_owner((cred_t *)cr, vfsp));
}
int
secpolicy_fs_config(const cred_t *cr, const vfs_t *vfsp)
{
return (secpolicy_fs_owner((cred_t *)cr, vfsp));
}
/* ARGSUSED */
int
secpolicy_fs_linkdir(const cred_t *cr, const vfs_t *vfsp)
{
return (PRIV_POLICY(cr, PRIV_SYS_LINKDIR, B_FALSE, EPERM, NULL));
}
/*
* Name: secpolicy_vnode_access()
*
* Parameters: Process credential
* vnode
* uid of owner of vnode
* permission bits not granted to the caller when examining
* file mode bits (i.e., when a process wants to open a
* mode 444 file for VREAD|VWRITE, this function should be
* called only with a VWRITE argument).
*
* Normal: Verifies that cred has the appropriate privileges to
* override the mode bits that were denied.
*
* Override: file_dac_execute - if VEXEC bit was denied and vnode is
* not a directory.
* file_dac_read - if VREAD bit was denied.
* file_dac_search - if VEXEC bit was denied and vnode is
* a directory.
* file_dac_write - if VWRITE bit was denied.
*
* Root owned files are special cased to protect system
* configuration files and such.
*
* Output: EACCES - if privilege check fails.
*/
/* ARGSUSED */
int
secpolicy_vnode_access(const cred_t *cr, vnode_t *vp, uid_t owner, mode_t mode)
{
if ((mode & VREAD) && priv_policy_va(cr, PRIV_FILE_DAC_READ, B_FALSE,
EACCES, NULL, KLPDARG_VNODE, vp, (char *)NULL,
KLPDARG_NOMORE) != 0) {
return (EACCES);
}
if (mode & VWRITE) {
boolean_t allzone;
if (owner == 0 && cr->cr_uid != 0)
allzone = B_TRUE;
else
allzone = B_FALSE;
if (priv_policy_va(cr, PRIV_FILE_DAC_WRITE, allzone, EACCES,
NULL, KLPDARG_VNODE, vp, (char *)NULL,
KLPDARG_NOMORE) != 0) {
return (EACCES);
}
}
if (mode & VEXEC) {
/*
* Directories use file_dac_search to override the execute bit.
*/
int p = vp->v_type == VDIR ? PRIV_FILE_DAC_SEARCH :
PRIV_FILE_DAC_EXECUTE;
return (priv_policy_va(cr, p, B_FALSE, EACCES, NULL,
KLPDARG_VNODE, vp, (char *)NULL, KLPDARG_NOMORE));
}
return (0);
}
/*
* Name: secpolicy_vnode_setid_modify()
*
* Normal: verify that subject can set the file setid flags.
*
* Output: EPERM - if not privileged.
*/
static int
secpolicy_vnode_setid_modify(const cred_t *cr, uid_t owner)
{
/* If changing to suid root, must have all zone privs */
boolean_t allzone = B_TRUE;
if (owner != 0) {
if (owner == cr->cr_uid)
return (0);
allzone = B_FALSE;
}
return (PRIV_POLICY(cr, PRIV_FILE_SETID, allzone, EPERM, NULL));
}
/*
* Are we allowed to retain the set-uid/set-gid bits when
* changing ownership or when writing to a file?
* "issuid" should be true when set-uid; only in that case
* root ownership is checked (setgid is assumed).
*/
int
secpolicy_vnode_setid_retain(const cred_t *cred, boolean_t issuidroot)
{
if (issuidroot && !HAS_ALLZONEPRIVS(cred))
return (EPERM);
return (!PRIV_POLICY_CHOICE(cred, PRIV_FILE_SETID, B_FALSE));
}
/*
* Name: secpolicy_vnode_setids_setgids()
*
* Normal: verify that subject can set the file setgid flag.
*
* Output: EPERM - if not privileged
*/
int
secpolicy_vnode_setids_setgids(const cred_t *cred, gid_t gid)
{
if (!groupmember(gid, cred))
return (PRIV_POLICY(cred, PRIV_FILE_SETID, B_FALSE, EPERM,
NULL));
return (0);
}
/*
* Name: secpolicy_vnode_chown
*
* Normal: Determine if subject can chown owner of a file.
*
* Output: EPERM - if access denied
*/
int
secpolicy_vnode_chown(const cred_t *cred, boolean_t check_self)
{
if (HAS_PRIVILEGE(cred, PRIV_FILE_CHOWN))
return (PRIV_POLICY(cred, PRIV_FILE_CHOWN, B_FALSE, EPERM,
NULL));
else if (check_self)
return (PRIV_POLICY(cred, PRIV_FILE_CHOWN_SELF, B_FALSE, EPERM,
NULL));
else
return (EPERM);
}
/*
* Name: secpolicy_vnode_create_gid
*
* Normal: Determine if subject can change group ownership of a file.
*
* Output: EPERM - if access denied
*/
int
secpolicy_vnode_create_gid(const cred_t *cred)
{
return (secpolicy_vnode_chown(cred, B_TRUE));
}
/*
* Name: secpolicy_vnode_utime_modify()
*
* Normal: verify that subject can modify the utime on a file.
*
* Output: EPERM - if access denied.
*/
static int
secpolicy_vnode_utime_modify(const cred_t *cred)
{
return (PRIV_POLICY(cred, PRIV_FILE_OWNER, B_FALSE, EPERM,
"modify file times"));
}
/*
* Name: secpolicy_vnode_setdac()
*
* Normal: verify that subject can modify the mode of a file.
* allzone privilege needed when modifying root owned object.
*
* Output: EPERM - if access denied.
*/
int
secpolicy_vnode_setdac(const cred_t *cred, uid_t owner)
{
if (owner == cred->cr_uid)
return (0);
return (PRIV_POLICY(cred, PRIV_FILE_OWNER, owner == 0, EPERM, NULL));
}
/*
* Name: secpolicy_vnode_stky_modify()
*
* Normal: verify that subject can make a file a "sticky".
*
* Output: EPERM - if access denied.
*/
int
secpolicy_vnode_stky_modify(const cred_t *cred)
{
return (PRIV_POLICY(cred, PRIV_SYS_CONFIG, B_FALSE, EPERM,
"set file sticky"));
}
/*
* Policy determines whether we can remove an entry from a directory,
* regardless of permission bits.
*/
int
secpolicy_vnode_remove(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_FILE_OWNER, B_FALSE, EACCES,
"sticky directory"));
}
int
secpolicy_vnode_owner(const cred_t *cr, uid_t owner)
{
boolean_t allzone = (owner == 0);
if (owner == cr->cr_uid)
return (0);
return (PRIV_POLICY(cr, PRIV_FILE_OWNER, allzone, EPERM, NULL));
}
void
secpolicy_setid_clear(vattr_t *vap, cred_t *cr)
{
if ((vap->va_mode & (S_ISUID | S_ISGID)) != 0 &&
secpolicy_vnode_setid_retain(cr,
(vap->va_mode & S_ISUID) != 0 &&
(vap->va_mask & AT_UID) != 0 && vap->va_uid == 0) != 0) {
vap->va_mask |= AT_MODE;
vap->va_mode &= ~(S_ISUID|S_ISGID);
}
}
int
secpolicy_setid_setsticky_clear(vnode_t *vp, vattr_t *vap, const vattr_t *ovap,
cred_t *cr)
{
int error;
if ((vap->va_mode & S_ISUID) != 0 &&
(error = secpolicy_vnode_setid_modify(cr,
ovap->va_uid)) != 0) {
return (error);
}
/*
* Check privilege if attempting to set the
* sticky bit on a non-directory.
*/
if (vp->v_type != VDIR && (vap->va_mode & S_ISVTX) != 0 &&
secpolicy_vnode_stky_modify(cr) != 0) {
vap->va_mode &= ~S_ISVTX;
}
/*
* Check for privilege if attempting to set the
* group-id bit.
*/
if ((vap->va_mode & S_ISGID) != 0 &&
secpolicy_vnode_setids_setgids(cr, ovap->va_gid) != 0) {
vap->va_mode &= ~S_ISGID;
}
return (0);
}
#define ATTR_FLAG_PRIV(attr, value, cr) \
PRIV_POLICY(cr, value ? PRIV_FILE_FLAG_SET : PRIV_ALL, \
B_FALSE, EPERM, NULL)
/*
* Check privileges for setting xvattr attributes
*/
int
secpolicy_xvattr(xvattr_t *xvap, uid_t owner, cred_t *cr, vtype_t vtype)
{
xoptattr_t *xoap;
int error = 0;
if ((xoap = xva_getxoptattr(xvap)) == NULL)
return (EINVAL);
/*
* First process the DOS bits
*/
if (XVA_ISSET_REQ(xvap, XAT_ARCHIVE) ||
XVA_ISSET_REQ(xvap, XAT_HIDDEN) ||
XVA_ISSET_REQ(xvap, XAT_READONLY) ||
XVA_ISSET_REQ(xvap, XAT_SYSTEM) ||
XVA_ISSET_REQ(xvap, XAT_CREATETIME)) {
if ((error = secpolicy_vnode_owner(cr, owner)) != 0)
return (error);
}
/*
* Now handle special attributes
*/
if (XVA_ISSET_REQ(xvap, XAT_IMMUTABLE))
error = ATTR_FLAG_PRIV(XAT_IMMUTABLE,
xoap->xoa_immutable, cr);
if (error == 0 && XVA_ISSET_REQ(xvap, XAT_NOUNLINK))
error = ATTR_FLAG_PRIV(XAT_NOUNLINK,
xoap->xoa_nounlink, cr);
if (error == 0 && XVA_ISSET_REQ(xvap, XAT_APPENDONLY))
error = ATTR_FLAG_PRIV(XAT_APPENDONLY,
xoap->xoa_appendonly, cr);
if (error == 0 && XVA_ISSET_REQ(xvap, XAT_NODUMP))
error = ATTR_FLAG_PRIV(XAT_NODUMP,
xoap->xoa_nodump, cr);
if (error == 0 && XVA_ISSET_REQ(xvap, XAT_OPAQUE))
error = EPERM;
if (error == 0 && XVA_ISSET_REQ(xvap, XAT_AV_QUARANTINED)) {
error = ATTR_FLAG_PRIV(XAT_AV_QUARANTINED,
xoap->xoa_av_quarantined, cr);
if (error == 0 && vtype != VREG && xoap->xoa_av_quarantined)
error = EINVAL;
}
if (error == 0 && XVA_ISSET_REQ(xvap, XAT_AV_MODIFIED))
error = ATTR_FLAG_PRIV(XAT_AV_MODIFIED,
xoap->xoa_av_modified, cr);
if (error == 0 && XVA_ISSET_REQ(xvap, XAT_AV_SCANSTAMP)) {
error = ATTR_FLAG_PRIV(XAT_AV_SCANSTAMP,
xoap->xoa_av_scanstamp, cr);
if (error == 0 && vtype != VREG)
error = EINVAL;
}
return (error);
}
/*
* This function checks the policy decisions surrounding the
* vop setattr call.
*
* It should be called after sufficient locks have been established
* on the underlying data structures. No concurrent modifications
* should be allowed.
*
* The caller must pass in unlocked version of its vaccess function
* this is required because vop_access function should lock the
* node for reading. A three argument function should be defined
* which accepts the following argument:
* A pointer to the internal "node" type (inode *)
* vnode access bits (VREAD|VWRITE|VEXEC)
* a pointer to the credential
*
* This function makes the following policy decisions:
*
* - change permissions
* - permission to change file mode if not owner
* - permission to add sticky bit to non-directory
* - permission to add set-gid bit
*
* The ovap argument should include AT_MODE|AT_UID|AT_GID.
*
* If the vap argument does not include AT_MODE, the mode will be copied from
* ovap. In certain situations set-uid/set-gid bits need to be removed;
* this is done by marking vap->va_mask to include AT_MODE and va_mode
* is updated to the newly computed mode.
*/
int
secpolicy_vnode_setattr(cred_t *cr, struct vnode *vp, struct vattr *vap,
const struct vattr *ovap, int flags,
int unlocked_access(void *, int, cred_t *),
void *node)
{
int mask = vap->va_mask;
int error = 0;
boolean_t skipaclchk = (flags & ATTR_NOACLCHECK) ? B_TRUE : B_FALSE;
if (mask & AT_SIZE) {
if (vp->v_type == VDIR) {
error = EISDIR;
goto out;
}
/*
* If ATTR_NOACLCHECK is set in the flags, then we don't
* perform the secondary unlocked_access() call since the
* ACL (if any) is being checked there.
*/
if (skipaclchk == B_FALSE) {
error = unlocked_access(node, VWRITE, cr);
if (error)
goto out;
}
}
if (mask & AT_MODE) {
/*
* If not the owner of the file then check privilege
* for two things: the privilege to set the mode at all
* and, if we're setting setuid, we also need permissions
* to add the set-uid bit, if we're not the owner.
* In the specific case of creating a set-uid root
* file, we need even more permissions.
*/
if ((error = secpolicy_vnode_setdac(cr, ovap->va_uid)) != 0)
goto out;
if ((error = secpolicy_setid_setsticky_clear(vp, vap,
ovap, cr)) != 0)
goto out;
} else
vap->va_mode = ovap->va_mode;
if (mask & (AT_UID|AT_GID)) {
boolean_t checkpriv = B_FALSE;
int priv;
boolean_t allzone = B_FALSE;
/*
* Chowning files.
*
* If you are the file owner:
* chown to other uid FILE_CHOWN_SELF
* chown to gid (non-member) FILE_CHOWN_SELF
* chown to gid (member) <none>
*
* Instead of PRIV_FILE_CHOWN_SELF, FILE_CHOWN is also
* acceptable but the first one is reported when debugging.
*
* If you are not the file owner:
* chown from root PRIV_FILE_CHOWN + zone
* chown from other to any PRIV_FILE_CHOWN
*
*/
if (cr->cr_uid != ovap->va_uid) {
checkpriv = B_TRUE;
allzone = (ovap->va_uid == 0);
priv = PRIV_FILE_CHOWN;
} else {
if (((mask & AT_UID) && vap->va_uid != ovap->va_uid) ||
((mask & AT_GID) && vap->va_gid != ovap->va_gid &&
!groupmember(vap->va_gid, cr))) {
checkpriv = B_TRUE;
priv = HAS_PRIVILEGE(cr, PRIV_FILE_CHOWN) ?
PRIV_FILE_CHOWN : PRIV_FILE_CHOWN_SELF;
}
}
/*
* If necessary, check privilege to see if update can be done.
*/
if (checkpriv &&
(error = PRIV_POLICY(cr, priv, allzone, EPERM, NULL))
!= 0) {
goto out;
}
/*
* If the file has either the set UID or set GID bits
* set and the caller can set the bits, then leave them.
*/
secpolicy_setid_clear(vap, cr);
}
if (mask & (AT_ATIME|AT_MTIME)) {
/*
* If not the file owner and not otherwise privileged,
* always return an error when setting the
* time other than the current (ATTR_UTIME flag set).
* If setting the current time (ATTR_UTIME not set) then
* unlocked_access will check permissions according to policy.
*/
if (cr->cr_uid != ovap->va_uid) {
if (flags & ATTR_UTIME)
error = secpolicy_vnode_utime_modify(cr);
else if (skipaclchk == B_FALSE) {
error = unlocked_access(node, VWRITE, cr);
if (error == EACCES &&
secpolicy_vnode_utime_modify(cr) == 0)
error = 0;
}
if (error)
goto out;
}
}
/*
* Check for optional attributes here by checking the following:
*/
if (mask & AT_XVATTR)
error = secpolicy_xvattr((xvattr_t *)vap, ovap->va_uid, cr,
vp->v_type);
out:
return (error);
}
/*
* Name: secpolicy_pcfs_modify_bootpartition()
*
* Normal: verify that subject can modify a pcfs boot partition.
*
* Output: EACCES - if privilege check failed.
*/
/*ARGSUSED*/
int
secpolicy_pcfs_modify_bootpartition(const cred_t *cred)
{
return (PRIV_POLICY(cred, PRIV_ALL, B_FALSE, EACCES,
"modify pcfs boot partition"));
}
/*
* System V IPC routines
*/
int
secpolicy_ipc_owner(const cred_t *cr, const struct kipc_perm *ip)
{
if (crgetzoneid(cr) != ip->ipc_zoneid ||
(cr->cr_uid != ip->ipc_uid && cr->cr_uid != ip->ipc_cuid)) {
boolean_t allzone = B_FALSE;
if (ip->ipc_uid == 0 || ip->ipc_cuid == 0)
allzone = B_TRUE;
return (PRIV_POLICY(cr, PRIV_IPC_OWNER, allzone, EPERM, NULL));
}
return (0);
}
int
secpolicy_ipc_config(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_IPC_CONFIG, B_FALSE, EPERM, NULL));
}
int
secpolicy_ipc_access(const cred_t *cr, const struct kipc_perm *ip, mode_t mode)
{
boolean_t allzone = B_FALSE;
ASSERT((mode & (MSG_R|MSG_W)) != 0);
if ((mode & MSG_R) &&
PRIV_POLICY(cr, PRIV_IPC_DAC_READ, allzone, EACCES, NULL) != 0)
return (EACCES);
if (mode & MSG_W) {
if (cr->cr_uid != 0 && (ip->ipc_uid == 0 || ip->ipc_cuid == 0))
allzone = B_TRUE;
return (PRIV_POLICY(cr, PRIV_IPC_DAC_WRITE, allzone, EACCES,
NULL));
}
return (0);
}
int
secpolicy_rsm_access(const cred_t *cr, uid_t owner, mode_t mode)
{
boolean_t allzone = B_FALSE;
ASSERT((mode & (MSG_R|MSG_W)) != 0);
if ((mode & MSG_R) &&
PRIV_POLICY(cr, PRIV_IPC_DAC_READ, allzone, EACCES, NULL) != 0)
return (EACCES);
if (mode & MSG_W) {
if (cr->cr_uid != 0 && owner == 0)
allzone = B_TRUE;
return (PRIV_POLICY(cr, PRIV_IPC_DAC_WRITE, allzone, EACCES,
NULL));
}
return (0);
}
/*
* Audit configuration.
*/
int
secpolicy_audit_config(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_AUDIT, B_FALSE, EPERM, NULL));
}
/*
* Audit record generation.
*/
int
secpolicy_audit_modify(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_PROC_AUDIT, B_FALSE, EPERM, NULL));
}
/*
* Get audit attributes.
* Either PRIV_SYS_AUDIT or PRIV_PROC_AUDIT required; report the
* "Least" of the two privileges on error.
*/
int
secpolicy_audit_getattr(const cred_t *cr)
{
if (!PRIV_POLICY_ONLY(cr, PRIV_SYS_AUDIT, B_FALSE)) {
return (PRIV_POLICY(cr, PRIV_PROC_AUDIT, B_FALSE, EPERM,
NULL));
} else {
return (PRIV_POLICY(cr, PRIV_SYS_AUDIT, B_FALSE, EPERM, NULL));
}
}
/*
* Locking physical memory
*/
int
secpolicy_lock_memory(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_PROC_LOCK_MEMORY, B_FALSE, EPERM, NULL));
}
/*
* Accounting (both acct(2) and exacct).
*/
int
secpolicy_acct(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_ACCT, B_FALSE, EPERM, NULL));
}
/*
* Is this process privileged to change its uids at will?
* Uid 0 is still considered "special" and having the SETID
* privilege is not sufficient to get uid 0.
* Files are owned by root, so the privilege would give
* full access and euid 0 is still effective.
*
* If you have the privilege and euid 0 only then do you
* get the powers of root wrt uid 0.
*
* For gid manipulations, this is should be called with an
* uid of -1.
*
*/
int
secpolicy_allow_setid(const cred_t *cr, uid_t newuid, boolean_t checkonly)
{
boolean_t allzone = B_FALSE;
if (newuid == 0 && cr->cr_uid != 0 && cr->cr_suid != 0 &&
cr->cr_ruid != 0) {
allzone = B_TRUE;
}
return (checkonly ? !PRIV_POLICY_ONLY(cr, PRIV_PROC_SETID, allzone) :
PRIV_POLICY(cr, PRIV_PROC_SETID, allzone, EPERM, NULL));
}
/*
* Acting on a different process: if the mode is for writing,
* the restrictions are more severe. This is called after
* we've verified that the uids do not match.
*/
int
secpolicy_proc_owner(const cred_t *scr, const cred_t *tcr, int mode)
{
boolean_t allzone = B_FALSE;
if ((mode & VWRITE) && scr->cr_uid != 0 &&
(tcr->cr_uid == 0 || tcr->cr_ruid == 0 || tcr->cr_suid == 0))
allzone = B_TRUE;
return (PRIV_POLICY(scr, PRIV_PROC_OWNER, allzone, EPERM, NULL));
}
int
secpolicy_proc_access(const cred_t *scr)
{
return (PRIV_POLICY(scr, PRIV_PROC_OWNER, B_FALSE, EACCES, NULL));
}
int
secpolicy_proc_excl_open(const cred_t *scr)
{
return (PRIV_POLICY(scr, PRIV_PROC_OWNER, B_FALSE, EBUSY, NULL));
}
int
secpolicy_proc_zone(const cred_t *scr)
{
return (PRIV_POLICY(scr, PRIV_PROC_ZONE, B_FALSE, EPERM, NULL));
}
/*
* Destroying the system
*/
int
secpolicy_kmdb(const cred_t *scr)
{
return (PRIV_POLICY(scr, PRIV_ALL, B_FALSE, EPERM, NULL));
}
int
secpolicy_error_inject(const cred_t *scr)
{
return (PRIV_POLICY(scr, PRIV_ALL, B_FALSE, EPERM, NULL));
}
/*
* Processor sets, cpu configuration, resource pools.
*/
int
secpolicy_pset(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_RES_CONFIG, B_FALSE, EPERM, NULL));
}
int
secpolicy_ponline(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_RES_CONFIG, B_FALSE, EPERM, NULL));
}
int
secpolicy_pool(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_RES_CONFIG, B_FALSE, EPERM, NULL));
}
int
secpolicy_blacklist(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_RES_CONFIG, B_FALSE, EPERM, NULL));
}
/*
* Catch all system configuration.
*/
int
secpolicy_sys_config(const cred_t *cr, boolean_t checkonly)
{
if (checkonly) {
return (PRIV_POLICY_ONLY(cr, PRIV_SYS_CONFIG, B_FALSE) ? 0 :
EPERM);
} else {
return (PRIV_POLICY(cr, PRIV_SYS_CONFIG, B_FALSE, EPERM, NULL));
}
}
/*
* Zone administration (halt, reboot, etc.) from within zone.
*/
int
secpolicy_zone_admin(const cred_t *cr, boolean_t checkonly)
{
if (checkonly) {
return (PRIV_POLICY_ONLY(cr, PRIV_SYS_ADMIN, B_FALSE) ? 0 :
EPERM);
} else {
return (PRIV_POLICY(cr, PRIV_SYS_ADMIN, B_FALSE, EPERM,
NULL));
}
}
/*
* Zone configuration (create, halt, enter).
*/
int
secpolicy_zone_config(const cred_t *cr)
{
/*
* Require all privileges to avoid possibility of privilege
* escalation.
*/
return (secpolicy_require_set(cr, PRIV_FULLSET, NULL));
}
/*
* Various other system configuration calls
*/
int
secpolicy_coreadm(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_ADMIN, B_FALSE, EPERM, NULL));
}
int
secpolicy_systeminfo(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_ADMIN, B_FALSE, EPERM, NULL));
}
int
secpolicy_dispadm(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_CONFIG, B_FALSE, EPERM, NULL));
}
int
secpolicy_settime(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_TIME, B_FALSE, EPERM, NULL));
}
/*
* For realtime users: high resolution clock.
*/
int
secpolicy_clock_highres(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_PROC_CLOCK_HIGHRES, B_FALSE, EPERM,
NULL));
}
/*
* drv_priv() is documented as callable from interrupt context, not that
* anyone ever does, but still. No debugging or auditing can be done when
* it is called from interrupt context.
* returns 0 on succes, EPERM on failure.
*/
int
drv_priv(cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_DEVICES, B_FALSE, EPERM, NULL));
}
int
secpolicy_sys_devices(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_DEVICES, B_FALSE, EPERM, NULL));
}
int
secpolicy_excl_open(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_DEVICES, B_FALSE, EBUSY, NULL));
}
int
secpolicy_rctlsys(const cred_t *cr, boolean_t is_zone_rctl)
{
/* zone.* rctls can only be set from the global zone */
if (is_zone_rctl && priv_policy_global(cr) != 0)
return (EPERM);
return (PRIV_POLICY(cr, PRIV_SYS_RESOURCE, B_FALSE, EPERM, NULL));
}
int
secpolicy_resource(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_RESOURCE, B_FALSE, EPERM, NULL));
}
/*
* Processes with a real uid of 0 escape any form of accounting, much
* like before.
*/
int
secpolicy_newproc(const cred_t *cr)
{
if (cr->cr_ruid == 0)
return (0);
return (PRIV_POLICY(cr, PRIV_SYS_RESOURCE, B_FALSE, EPERM, NULL));
}
/*
* Networking
*/
int
secpolicy_net_rawaccess(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_NET_RAWACCESS, B_FALSE, EACCES, NULL));
}
/*
* Need this privilege for accessing the ICMP device
*/
int
secpolicy_net_icmpaccess(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_NET_ICMPACCESS, B_FALSE, EACCES, NULL));
}
/*
* There are a few rare cases where the kernel generates ioctls() from
* interrupt context with a credential of kcred rather than NULL.
* In those cases, we take the safe and cheap test.
*/
int
secpolicy_net_config(const cred_t *cr, boolean_t checkonly)
{
if (checkonly) {
return (PRIV_POLICY_ONLY(cr, PRIV_SYS_NET_CONFIG, B_FALSE) ?
0 : EPERM);
} else {
return (PRIV_POLICY(cr, PRIV_SYS_NET_CONFIG, B_FALSE, EPERM,
NULL));
}
}
/*
* PRIV_SYS_NET_CONFIG is a superset of PRIV_SYS_IP_CONFIG.
*
* There are a few rare cases where the kernel generates ioctls() from
* interrupt context with a credential of kcred rather than NULL.
* In those cases, we take the safe and cheap test.
*/
int
secpolicy_ip_config(const cred_t *cr, boolean_t checkonly)
{
if (PRIV_POLICY_ONLY(cr, PRIV_SYS_NET_CONFIG, B_FALSE))
return (secpolicy_net_config(cr, checkonly));
if (checkonly) {
return (PRIV_POLICY_ONLY(cr, PRIV_SYS_IP_CONFIG, B_FALSE) ?
0 : EPERM);
} else {
return (PRIV_POLICY(cr, PRIV_SYS_IP_CONFIG, B_FALSE, EPERM,
NULL));
}
}
/*
* PRIV_SYS_NET_CONFIG is a superset of PRIV_SYS_DL_CONFIG.
*/
int
secpolicy_dl_config(const cred_t *cr)
{
if (PRIV_POLICY_ONLY(cr, PRIV_SYS_NET_CONFIG, B_FALSE))
return (secpolicy_net_config(cr, B_FALSE));
return (PRIV_POLICY(cr, PRIV_SYS_DL_CONFIG, B_FALSE, EPERM,
NULL));
}
/*
* Map IP pseudo privileges to actual privileges.
* So we don't need to recompile IP when we change the privileges.
*/
int
secpolicy_ip(const cred_t *cr, int netpriv, boolean_t checkonly)
{
int priv = PRIV_ALL;
switch (netpriv) {
case OP_CONFIG:
priv = PRIV_SYS_IP_CONFIG;
break;
case OP_RAW:
priv = PRIV_NET_RAWACCESS;
break;
case OP_PRIVPORT:
priv = PRIV_NET_PRIVADDR;
break;
}
ASSERT(priv != PRIV_ALL);
if (checkonly)
return (PRIV_POLICY_ONLY(cr, priv, B_FALSE) ? 0 : EPERM);
else
return (PRIV_POLICY(cr, priv, B_FALSE, EPERM, NULL));
}
/*
* Map network pseudo privileges to actual privileges.
* So we don't need to recompile IP when we change the privileges.
*/
int
secpolicy_net(const cred_t *cr, int netpriv, boolean_t checkonly)
{
int priv = PRIV_ALL;
switch (netpriv) {
case OP_CONFIG:
priv = PRIV_SYS_NET_CONFIG;
break;
case OP_RAW:
priv = PRIV_NET_RAWACCESS;
break;
case OP_PRIVPORT:
priv = PRIV_NET_PRIVADDR;
break;
}
ASSERT(priv != PRIV_ALL);
if (checkonly)
return (PRIV_POLICY_ONLY(cr, priv, B_FALSE) ? 0 : EPERM);
else
return (PRIV_POLICY(cr, priv, B_FALSE, EPERM, NULL));
}
/*
* Checks for operations that are either client-only or are used by
* both clients and servers.
*/
int
secpolicy_nfs(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_NFS, B_FALSE, EPERM, NULL));
}
/*
* Special case for opening rpcmod: have NFS privileges or network
* config privileges.
*/
int
secpolicy_rpcmod_open(const cred_t *cr)
{
if (PRIV_POLICY_ONLY(cr, PRIV_SYS_NFS, B_FALSE))
return (secpolicy_nfs(cr));
else
return (secpolicy_net_config(cr, NULL));
}
int
secpolicy_chroot(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_PROC_CHROOT, B_FALSE, EPERM, NULL));
}
int
secpolicy_tasksys(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_PROC_TASKID, B_FALSE, EPERM, NULL));
}
/*
* Basic privilege checks.
*/
int
secpolicy_basic_exec(const cred_t *cr, vnode_t *vp)
{
return (priv_policy_va(cr, PRIV_PROC_EXEC, B_FALSE, EPERM, NULL,
KLPDARG_VNODE, vp, (char *)NULL, KLPDARG_NOMORE));
}
int
secpolicy_basic_fork(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_PROC_FORK, B_FALSE, EPERM, NULL));
}
int
secpolicy_basic_proc(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_PROC_SESSION, B_FALSE, EPERM, NULL));
}
/*
* Slightly complicated because we don't want to trigger the policy too
* often. First we shortcircuit access to "self" (tp == sp) or if
* we don't have the privilege but if we have permission
* just return (0) and we don't flag the privilege as needed.
* Else, we test for the privilege because we either have it or need it.
*/
int
secpolicy_basic_procinfo(const cred_t *cr, proc_t *tp, proc_t *sp)
{
if (tp == sp ||
!HAS_PRIVILEGE(cr, PRIV_PROC_INFO) && prochasprocperm(tp, sp, cr)) {
return (0);
} else {
return (PRIV_POLICY(cr, PRIV_PROC_INFO, B_FALSE, EPERM, NULL));
}
}
int
secpolicy_basic_link(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_FILE_LINK_ANY, B_FALSE, EPERM, NULL));
}
/*
* Additional device protection.
*
* Traditionally, a device has specific permissions on the node in
* the filesystem which govern which devices can be opened by what
* processes. In certain cases, it is desirable to add extra
* restrictions, as writing to certain devices is identical to
* having a complete run of the system.
*
* This mechanism is called the device policy.
*
* When a device is opened, its policy entry is looked up in the
* policy cache and checked.
*/
int
secpolicy_spec_open(const cred_t *cr, struct vnode *vp, int oflag)
{
devplcy_t *plcy;
int err;
struct snode *csp = VTOS(common_specvp(vp));
priv_set_t pset;
mutex_enter(&csp->s_lock);
if (csp->s_plcy == NULL || csp->s_plcy->dp_gen != devplcy_gen) {
plcy = devpolicy_find(vp);
if (csp->s_plcy)
dpfree(csp->s_plcy);
csp->s_plcy = plcy;
ASSERT(plcy != NULL);
} else
plcy = csp->s_plcy;
if (plcy == nullpolicy) {
mutex_exit(&csp->s_lock);
return (0);
}
dphold(plcy);
mutex_exit(&csp->s_lock);
if (oflag & FWRITE)
pset = plcy->dp_wrp;
else
pset = plcy->dp_rdp;
/*
* Special case:
* PRIV_SYS_NET_CONFIG is a superset of PRIV_SYS_IP_CONFIG.
* If PRIV_SYS_NET_CONFIG is present and PRIV_SYS_IP_CONFIG is
* required, replace PRIV_SYS_IP_CONFIG with PRIV_SYS_NET_CONFIG
* in the required privilege set before doing the check.
*/
if (priv_ismember(&pset, PRIV_SYS_IP_CONFIG) &&
priv_ismember(&CR_OEPRIV(cr), PRIV_SYS_NET_CONFIG) &&
!priv_ismember(&CR_OEPRIV(cr), PRIV_SYS_IP_CONFIG)) {
priv_delset(&pset, PRIV_SYS_IP_CONFIG);
priv_addset(&pset, PRIV_SYS_NET_CONFIG);
}
err = secpolicy_require_set(cr, &pset, "devpolicy");
dpfree(plcy);
return (err);
}
int
secpolicy_modctl(const cred_t *cr, int cmd)
{
switch (cmd) {
case MODINFO:
case MODGETMAJBIND:
case MODGETPATH:
case MODGETPATHLEN:
case MODGETNAME:
case MODGETFBNAME:
case MODGETDEVPOLICY:
case MODGETDEVPOLICYBYNAME:
case MODDEVT2INSTANCE:
case MODSIZEOF_DEVID:
case MODGETDEVID:
case MODSIZEOF_MINORNAME:
case MODGETMINORNAME:
case MODGETDEVFSPATH_LEN:
case MODGETDEVFSPATH:
case MODGETDEVFSPATH_MI_LEN:
case MODGETDEVFSPATH_MI:
/* Unprivileged */
return (0);
case MODLOAD:
case MODSETDEVPOLICY:
return (secpolicy_require_set(cr, PRIV_FULLSET, NULL));
default:
return (secpolicy_sys_config(cr, B_FALSE));
}
}
int
secpolicy_console(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_DEVICES, B_FALSE, EPERM, NULL));
}
int
secpolicy_power_mgmt(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_DEVICES, B_FALSE, EPERM, NULL));
}
/*
* Simulate terminal input; another escalation of privileges avenue.
*/
int
secpolicy_sti(const cred_t *cr)
{
return (secpolicy_require_set(cr, PRIV_FULLSET, NULL));
}
boolean_t
secpolicy_net_reply_equal(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_CONFIG, B_FALSE, EPERM, NULL));
}
int
secpolicy_swapctl(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_CONFIG, B_FALSE, EPERM, NULL));
}
int
secpolicy_cpc_cpu(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_CPC_CPU, B_FALSE, EACCES, NULL));
}
/*
* secpolicy_contract_identity
*
* Determine if the subject may set the process contract FMRI value
*/
int
secpolicy_contract_identity(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_CONTRACT_IDENTITY, B_FALSE, EPERM, NULL));
}
/*
* secpolicy_contract_observer
*
* Determine if the subject may observe a specific contract's events.
*/
int
secpolicy_contract_observer(const cred_t *cr, struct contract *ct)
{
if (contract_owned(ct, cr, B_FALSE))
return (0);
return (PRIV_POLICY(cr, PRIV_CONTRACT_OBSERVER, B_FALSE, EPERM, NULL));
}
/*
* secpolicy_contract_observer_choice
*
* Determine if the subject may observe any contract's events. Just
* tests privilege and audits on success.
*/
boolean_t
secpolicy_contract_observer_choice(const cred_t *cr)
{
return (PRIV_POLICY_CHOICE(cr, PRIV_CONTRACT_OBSERVER, B_FALSE));
}
/*
* secpolicy_contract_event
*
* Determine if the subject may request critical contract events or
* reliable contract event delivery.
*/
int
secpolicy_contract_event(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_CONTRACT_EVENT, B_FALSE, EPERM, NULL));
}
/*
* secpolicy_contract_event_choice
*
* Determine if the subject may retain contract events in its critical
* set when a change in other terms would normally require a change in
* the critical set. Just tests privilege and audits on success.
*/
boolean_t
secpolicy_contract_event_choice(const cred_t *cr)
{
return (PRIV_POLICY_CHOICE(cr, PRIV_CONTRACT_EVENT, B_FALSE));
}
/*
* secpolicy_gart_access
*
* Determine if the subject has sufficient priveleges to make ioctls to agpgart
* device.
*/
int
secpolicy_gart_access(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_GRAPHICS_ACCESS, B_FALSE, EPERM, NULL));
}
/*
* secpolicy_gart_map
*
* Determine if the subject has sufficient priveleges to map aperture range
* through agpgart driver.
*/
int
secpolicy_gart_map(const cred_t *cr)
{
if (PRIV_POLICY_ONLY(cr, PRIV_GRAPHICS_ACCESS, B_FALSE)) {
return (PRIV_POLICY(cr, PRIV_GRAPHICS_ACCESS, B_FALSE, EPERM,
NULL));
} else {
return (PRIV_POLICY(cr, PRIV_GRAPHICS_MAP, B_FALSE, EPERM,
NULL));
}
}
/*
* secpolicy_zinject
*
* Determine if the subject can inject faults in the ZFS fault injection
* framework. Requires all privileges.
*/
int
secpolicy_zinject(const cred_t *cr)
{
return (secpolicy_require_set(cr, PRIV_FULLSET, NULL));
}
/*
* secpolicy_zfs
*
* Determine if the subject has permission to manipulate ZFS datasets
* (not pools). Equivalent to the SYS_MOUNT privilege.
*/
int
secpolicy_zfs(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_MOUNT, B_FALSE, EPERM, NULL));
}
/*
* secpolicy_idmap
*
* Determine if the calling process has permissions to register an SID
* mapping daemon and allocate ephemeral IDs.
*/
int
secpolicy_idmap(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_FILE_SETID, B_TRUE, EPERM, NULL));
}
/*
* secpolicy_ucode_update
*
* Determine if the subject has sufficient privilege to update microcode.
*/
int
secpolicy_ucode_update(const cred_t *scr)
{
return (PRIV_POLICY(scr, PRIV_ALL, B_FALSE, EPERM, NULL));
}
/*
* secpolicy_sadopen
*
* Determine if the subject has sufficient privilege to access /dev/sad/admin.
* /dev/sad/admin appear in global zone and exclusive-IP zones only.
* In global zone, sys_config is required.
* In exclusive-IP zones, sys_ip_config is required.
* Note that sys_config is prohibited in non-global zones.
*/
int
secpolicy_sadopen(const cred_t *credp)
{
priv_set_t pset;
priv_emptyset(&pset);
if (crgetzoneid(credp) == GLOBAL_ZONEID)
priv_addset(&pset, PRIV_SYS_CONFIG);
else
priv_addset(&pset, PRIV_SYS_IP_CONFIG);
return (secpolicy_require_set(credp, &pset, "devpolicy"));
}
/*
* Add privileges to a particular privilege set; this is called when the
* current sets of privileges are not sufficient. I.e., we should always
* call the policy override functions from here.
* What we are allowed to have is in the Observed Permitted set; so
* we compute the difference between that and the newset.
*/
int
secpolicy_require_privs(const cred_t *cr, const priv_set_t *nset)
{
priv_set_t rqd;
rqd = CR_OPPRIV(cr);
priv_inverse(&rqd);
priv_intersect(nset, &rqd);
return (secpolicy_require_set(cr, &rqd, NULL));
}
/*
* secpolicy_smb
*
* Determine if the cred_t has PRIV_SYS_SMB privilege, indicating
* that it has permission to access the smbsrv kernel driver.
* PRIV_POLICY checks the privilege and audits the check.
*
* Returns:
* 0 Driver access is allowed.
* EPERM Driver access is NOT permitted.
*/
int
secpolicy_smb(const cred_t *cr)
{
return (PRIV_POLICY(cr, PRIV_SYS_SMB, B_FALSE, EPERM, NULL));
}
/*
* secpolicy_vscan
*
* Determine if cred_t has the necessary privileges to access a file
* for virus scanning and update its extended system attributes.
* PRIV_FILE_DAC_SEARCH, PRIV_FILE_DAC_READ - file access
* PRIV_FILE_FLAG_SET - set extended system attributes
*
* PRIV_POLICY checks the privilege and audits the check.
*
* Returns:
* 0 file access for virus scanning allowed.
* EPERM file access for virus scanning is NOT permitted.
*/
int
secpolicy_vscan(const cred_t *cr)
{
if ((PRIV_POLICY(cr, PRIV_FILE_DAC_SEARCH, B_FALSE, EPERM, NULL)) ||
(PRIV_POLICY(cr, PRIV_FILE_DAC_READ, B_FALSE, EPERM, NULL)) ||
(PRIV_POLICY(cr, PRIV_FILE_FLAG_SET, B_FALSE, EPERM, NULL))) {
return (EPERM);
}
return (0);
}
/*
* secpolicy_smbfs_login
*
* Determines if the caller can add and delete the smbfs login
* password in the the nsmb kernel module for the CIFS client.
*
* Returns:
* 0 access is allowed.
* EPERM access is NOT allowed.
*/
int
secpolicy_smbfs_login(const cred_t *cr, uid_t uid)
{
uid_t cruid = crgetruid(cr);
if (cruid == uid)
return (0);
return (PRIV_POLICY(cr, PRIV_PROC_OWNER, B_FALSE,
EPERM, NULL));
}
/*
* secpolicy_xvm_control
*
* Determines if a caller can control the xVM hypervisor and/or running
* domains (x86 specific).
*
* Returns:
* 0 access is allowed.
* EPERM access is NOT allowed.
*/
int
secpolicy_xvm_control(const cred_t *cr)
{
if (PRIV_POLICY(cr, PRIV_XVM_CONTROL, B_FALSE, EPERM, NULL))
return (EPERM);
return (0);
}
/*
* secpolicy_dld_ioctl
*
* Determine if the subject has permission to use certain dld ioctls.
* Each ioctl should require a limited number of privileges. A large
* number indicates a poor design.
*/
int
secpolicy_dld_ioctl(const cred_t *cr, const char *dld_priv, const char *msg)
{
int rv;
if ((rv = priv_getbyname(dld_priv, 0)) >= 0) {
return (PRIV_POLICY(cr, rv, B_FALSE, EPERM, msg));
}
/* priv_getbyname() returns -ve errno */
return (-rv);
}