xref: /onnv-gate/usr/src/uts/common/os/priv.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 2003 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate /*
30*0Sstevel@tonic-gate  * Privilege implementation.
31*0Sstevel@tonic-gate  *
32*0Sstevel@tonic-gate  * This file provides the infrastructure for privilege sets and limits
33*0Sstevel@tonic-gate  * the number of files that requires to include <sys/cred_impl.h> and/or
34*0Sstevel@tonic-gate  * <sys/priv_impl.h>.
35*0Sstevel@tonic-gate  *
36*0Sstevel@tonic-gate  * The Solaris privilege mechanism has been designed in a
37*0Sstevel@tonic-gate  * future proof manner.  While the kernel may use fixed size arrays
38*0Sstevel@tonic-gate  * and fixed bitmasks and bit values, the representation of those
39*0Sstevel@tonic-gate  * is kernel private.  All external interfaces as well as K-to-K interfaces
40*0Sstevel@tonic-gate  * have been constructed in a manner to provide the maximum flexibility.
41*0Sstevel@tonic-gate  *
42*0Sstevel@tonic-gate  * There can be X privilege sets each containing Y 32 bit words.
43*0Sstevel@tonic-gate  * <X, Y> are constant for a kernel invocation.
44*0Sstevel@tonic-gate  *
45*0Sstevel@tonic-gate  * As a consequence, all privilege set manipulation happens in functions
46*0Sstevel@tonic-gate  * below.
47*0Sstevel@tonic-gate  *
48*0Sstevel@tonic-gate  */
49*0Sstevel@tonic-gate 
50*0Sstevel@tonic-gate #include <sys/systm.h>
51*0Sstevel@tonic-gate #include <sys/ddi.h>
52*0Sstevel@tonic-gate #include <sys/kmem.h>
53*0Sstevel@tonic-gate #include <sys/sunddi.h>
54*0Sstevel@tonic-gate #include <sys/errno.h>
55*0Sstevel@tonic-gate #include <sys/debug.h>
56*0Sstevel@tonic-gate #include <sys/priv_impl.h>
57*0Sstevel@tonic-gate #include <sys/procfs.h>
58*0Sstevel@tonic-gate #include <sys/policy.h>
59*0Sstevel@tonic-gate #include <sys/cred_impl.h>
60*0Sstevel@tonic-gate #include <sys/devpolicy.h>
61*0Sstevel@tonic-gate #include <sys/atomic.h>
62*0Sstevel@tonic-gate 
63*0Sstevel@tonic-gate /*
64*0Sstevel@tonic-gate  * Privilege name to number mapping table consists in the generated
65*0Sstevel@tonic-gate  * priv_const.c file.  This lock protects against updates of the privilege
66*0Sstevel@tonic-gate  * names and counts; all other priv_info fields are read-only.
67*0Sstevel@tonic-gate  * The actual protected values are:
68*0Sstevel@tonic-gate  *	global variable nprivs
69*0Sstevel@tonic-gate  *	the priv_max field
70*0Sstevel@tonic-gate  *	the priv_names field
71*0Sstevel@tonic-gate  *	the priv names info item (cnt/strings)
72*0Sstevel@tonic-gate  */
73*0Sstevel@tonic-gate krwlock_t privinfo_lock;
74*0Sstevel@tonic-gate 
75*0Sstevel@tonic-gate static boolean_t priv_valid(const cred_t *);
76*0Sstevel@tonic-gate 
77*0Sstevel@tonic-gate priv_set_t priv_fullset;	/* set of all privileges */
78*0Sstevel@tonic-gate priv_set_t priv_unsafe;	/* unsafe to exec set-uid root if these are not in L */
79*0Sstevel@tonic-gate 
80*0Sstevel@tonic-gate /*
81*0Sstevel@tonic-gate  * Privilege initialization functions.
82*0Sstevel@tonic-gate  * Called from common/os/cred.c when cred_init is called.
83*0Sstevel@tonic-gate  */
84*0Sstevel@tonic-gate 
85*0Sstevel@tonic-gate void
86*0Sstevel@tonic-gate priv_init(void)
87*0Sstevel@tonic-gate {
88*0Sstevel@tonic-gate 	rw_init(&privinfo_lock, NULL, RW_DRIVER, NULL);
89*0Sstevel@tonic-gate 
90*0Sstevel@tonic-gate 	PRIV_BASIC_ASSERT(priv_basic);
91*0Sstevel@tonic-gate 	PRIV_UNSAFE_ASSERT(&priv_unsafe);
92*0Sstevel@tonic-gate 	priv_fillset(&priv_fullset);
93*0Sstevel@tonic-gate 
94*0Sstevel@tonic-gate 	devpolicy_init();
95*0Sstevel@tonic-gate }
96*0Sstevel@tonic-gate 
97*0Sstevel@tonic-gate /* Utility functions: privilege sets as opaque data types */
98*0Sstevel@tonic-gate 
99*0Sstevel@tonic-gate /*
100*0Sstevel@tonic-gate  * Guts of prgetprivsize.
101*0Sstevel@tonic-gate  */
102*0Sstevel@tonic-gate int
103*0Sstevel@tonic-gate priv_prgetprivsize(prpriv_t *tmpl)
104*0Sstevel@tonic-gate {
105*0Sstevel@tonic-gate 	return (sizeof (prpriv_t) +
106*0Sstevel@tonic-gate 		PRIV_SETBYTES - sizeof (priv_chunk_t) +
107*0Sstevel@tonic-gate 		(tmpl ? tmpl->pr_infosize : priv_info->priv_infosize));
108*0Sstevel@tonic-gate }
109*0Sstevel@tonic-gate 
110*0Sstevel@tonic-gate /*
111*0Sstevel@tonic-gate  * Guts of prgetpriv.
112*0Sstevel@tonic-gate  */
113*0Sstevel@tonic-gate void
114*0Sstevel@tonic-gate cred2prpriv(const cred_t *cp, prpriv_t *pr)
115*0Sstevel@tonic-gate {
116*0Sstevel@tonic-gate 	priv_set_t *psa;
117*0Sstevel@tonic-gate 	int i;
118*0Sstevel@tonic-gate 
119*0Sstevel@tonic-gate 	pr->pr_nsets = PRIV_NSET;
120*0Sstevel@tonic-gate 	pr->pr_setsize = PRIV_SETSIZE;
121*0Sstevel@tonic-gate 	pr->pr_infosize = priv_info->priv_infosize;
122*0Sstevel@tonic-gate 
123*0Sstevel@tonic-gate 	psa = (priv_set_t *)pr->pr_sets;
124*0Sstevel@tonic-gate 
125*0Sstevel@tonic-gate 	for (i = 0; i < PRIV_NSET; i++)
126*0Sstevel@tonic-gate 		psa[i] = *priv_getset(cp, i);
127*0Sstevel@tonic-gate 
128*0Sstevel@tonic-gate 	priv_getinfo(cp, (char *)pr + PRIV_PRPRIV_INFO_OFFSET(pr));
129*0Sstevel@tonic-gate }
130*0Sstevel@tonic-gate 
131*0Sstevel@tonic-gate /*
132*0Sstevel@tonic-gate  * Guts of pr_spriv:
133*0Sstevel@tonic-gate  *
134*0Sstevel@tonic-gate  * Set the privileges of a process.
135*0Sstevel@tonic-gate  *
136*0Sstevel@tonic-gate  * In order to set the privileges, the setting process will need to
137*0Sstevel@tonic-gate  * have those privileges in its effective set in order to prevent
138*0Sstevel@tonic-gate  * specially privileged processes to easily gain additional privileges.
139*0Sstevel@tonic-gate  * Pre-existing privileges can be retained.  To change any privileges,
140*0Sstevel@tonic-gate  * PRIV_PROC_OWNER needs to be asserted.
141*0Sstevel@tonic-gate  *
142*0Sstevel@tonic-gate  * In formula:
143*0Sstevel@tonic-gate  *
144*0Sstevel@tonic-gate  *	S' <= S || S' <= S + Ea
145*0Sstevel@tonic-gate  *
146*0Sstevel@tonic-gate  * the new set must either be subset of the old set or a subset of
147*0Sstevel@tonic-gate  * the oldset merged with the effective set of the acting process; or just:
148*0Sstevel@tonic-gate  *
149*0Sstevel@tonic-gate  *	S' <= S + Ea
150*0Sstevel@tonic-gate  *
151*0Sstevel@tonic-gate  * It's not legal to grow the limit set this way.
152*0Sstevel@tonic-gate  *
153*0Sstevel@tonic-gate  */
154*0Sstevel@tonic-gate int
155*0Sstevel@tonic-gate priv_pr_spriv(proc_t *p, prpriv_t *prpriv, const cred_t *cr)
156*0Sstevel@tonic-gate {
157*0Sstevel@tonic-gate 	cred_t *oldcred;
158*0Sstevel@tonic-gate 	cred_t *newcred;
159*0Sstevel@tonic-gate 	int i;
160*0Sstevel@tonic-gate 	int err = EPERM;
161*0Sstevel@tonic-gate 	cred_priv_t *cp, *ocp;
162*0Sstevel@tonic-gate 	priv_set_t eset;
163*0Sstevel@tonic-gate 
164*0Sstevel@tonic-gate 	ASSERT(MUTEX_HELD(&p->p_lock));
165*0Sstevel@tonic-gate 
166*0Sstevel@tonic-gate 	/*
167*0Sstevel@tonic-gate 	 * Set must have proper dimension; infosize must be absent
168*0Sstevel@tonic-gate 	 * or properly sized.
169*0Sstevel@tonic-gate 	 */
170*0Sstevel@tonic-gate 	if (prpriv->pr_nsets != PRIV_NSET ||
171*0Sstevel@tonic-gate 	    prpriv->pr_setsize != PRIV_SETSIZE ||
172*0Sstevel@tonic-gate 	    (prpriv->pr_infosize & (sizeof (uint32_t) - 1)) != 0 ||
173*0Sstevel@tonic-gate 	    prpriv->pr_infosize > priv_info->priv_infosize ||
174*0Sstevel@tonic-gate 	    prpriv->pr_infosize < 0)
175*0Sstevel@tonic-gate 		    return (EINVAL);
176*0Sstevel@tonic-gate 
177*0Sstevel@tonic-gate 	mutex_exit(&p->p_lock);
178*0Sstevel@tonic-gate 
179*0Sstevel@tonic-gate 	if (priv_proc_cred_perm(cr, p, &oldcred, VWRITE) != 0) {
180*0Sstevel@tonic-gate 		mutex_enter(&p->p_lock);
181*0Sstevel@tonic-gate 		return (EPERM);
182*0Sstevel@tonic-gate 	}
183*0Sstevel@tonic-gate 
184*0Sstevel@tonic-gate 	newcred = crdup(oldcred);
185*0Sstevel@tonic-gate 
186*0Sstevel@tonic-gate 	/* Copy the privilege sets from prpriv to newcred */
187*0Sstevel@tonic-gate 	bcopy(prpriv->pr_sets, CR_PRIVSETS(newcred), PRIV_SETBYTES);
188*0Sstevel@tonic-gate 
189*0Sstevel@tonic-gate 	cp = &newcred->cr_priv;
190*0Sstevel@tonic-gate 	ocp = &oldcred->cr_priv;
191*0Sstevel@tonic-gate 	eset = CR_OEPRIV(cr);
192*0Sstevel@tonic-gate 
193*0Sstevel@tonic-gate 	priv_intersect(&CR_LPRIV(oldcred), &eset);
194*0Sstevel@tonic-gate 
195*0Sstevel@tonic-gate 	/*
196*0Sstevel@tonic-gate 	 * Verify the constraints laid out:
197*0Sstevel@tonic-gate 	 * for the limit set, we require that the new set is a subset
198*0Sstevel@tonic-gate 	 * of the old limit set.
199*0Sstevel@tonic-gate 	 * for all other sets, we require that the new set is either a
200*0Sstevel@tonic-gate 	 * subset of the old set or a subset of the intersection of
201*0Sstevel@tonic-gate 	 * the old limit set and the effective set of the acting process.
202*0Sstevel@tonic-gate 	 */
203*0Sstevel@tonic-gate 	for (i = 0; i < PRIV_NSET; i++)
204*0Sstevel@tonic-gate 		if (!priv_issubset(&cp->crprivs[i], &ocp->crprivs[i]) &&
205*0Sstevel@tonic-gate 		    (i == PRIV_LIMIT || !priv_issubset(&cp->crprivs[i], &eset)))
206*0Sstevel@tonic-gate 			break;
207*0Sstevel@tonic-gate 
208*0Sstevel@tonic-gate 	crfree(oldcred);
209*0Sstevel@tonic-gate 
210*0Sstevel@tonic-gate 	if (i < PRIV_NSET || !priv_valid(newcred))
211*0Sstevel@tonic-gate 		goto err;
212*0Sstevel@tonic-gate 
213*0Sstevel@tonic-gate 	/* Load the settable privilege information */
214*0Sstevel@tonic-gate 	if (prpriv->pr_infosize > 0) {
215*0Sstevel@tonic-gate 		char *x = (char *)prpriv + PRIV_PRPRIV_INFO_OFFSET(prpriv);
216*0Sstevel@tonic-gate 		char *lastx = x + prpriv->pr_infosize;
217*0Sstevel@tonic-gate 
218*0Sstevel@tonic-gate 		while (x < lastx) {
219*0Sstevel@tonic-gate 			priv_info_t *pi = (priv_info_t *)x;
220*0Sstevel@tonic-gate 			priv_info_uint_t *pii;
221*0Sstevel@tonic-gate 
222*0Sstevel@tonic-gate 			switch (pi->priv_info_type) {
223*0Sstevel@tonic-gate 			case PRIV_INFO_FLAGS:
224*0Sstevel@tonic-gate 				pii = (priv_info_uint_t *)x;
225*0Sstevel@tonic-gate 				if (pii->info.priv_info_size != sizeof (*pii)) {
226*0Sstevel@tonic-gate 					err = EINVAL;
227*0Sstevel@tonic-gate 					goto err;
228*0Sstevel@tonic-gate 				}
229*0Sstevel@tonic-gate 				CR_FLAGS(newcred) &= ~PRIV_USER;
230*0Sstevel@tonic-gate 				CR_FLAGS(newcred) |= (pii->val & PRIV_USER);
231*0Sstevel@tonic-gate 				break;
232*0Sstevel@tonic-gate 			default:
233*0Sstevel@tonic-gate 				err = EINVAL;
234*0Sstevel@tonic-gate 				goto err;
235*0Sstevel@tonic-gate 			}
236*0Sstevel@tonic-gate 			/* Guarantee alignment and forward progress */
237*0Sstevel@tonic-gate 			if ((pi->priv_info_size & (sizeof (uint32_t) - 1)) ||
238*0Sstevel@tonic-gate 			    pi->priv_info_size < sizeof (*pi) ||
239*0Sstevel@tonic-gate 			    lastx - x > pi->priv_info_size) {
240*0Sstevel@tonic-gate 				err = EINVAL;
241*0Sstevel@tonic-gate 				goto err;
242*0Sstevel@tonic-gate 			}
243*0Sstevel@tonic-gate 
244*0Sstevel@tonic-gate 			x += pi->priv_info_size;
245*0Sstevel@tonic-gate 		}
246*0Sstevel@tonic-gate 	}
247*0Sstevel@tonic-gate 
248*0Sstevel@tonic-gate 	/*
249*0Sstevel@tonic-gate 	 * We'll try to copy the privilege aware flag; but since the
250*0Sstevel@tonic-gate 	 * privileges sets are all individually set, they are set
251*0Sstevel@tonic-gate 	 * as if we're privilege aware.  If PRIV_AWARE wasn't set
252*0Sstevel@tonic-gate 	 * or was explicitely unset, we need to set the flag and then
253*0Sstevel@tonic-gate 	 * try to get rid of it.
254*0Sstevel@tonic-gate 	 */
255*0Sstevel@tonic-gate 	if ((CR_FLAGS(newcred) & PRIV_AWARE) == 0) {
256*0Sstevel@tonic-gate 		CR_FLAGS(newcred) |= PRIV_AWARE;
257*0Sstevel@tonic-gate 		priv_adjust_PA(newcred);
258*0Sstevel@tonic-gate 	}
259*0Sstevel@tonic-gate 
260*0Sstevel@tonic-gate 	mutex_enter(&p->p_crlock);
261*0Sstevel@tonic-gate 	oldcred = p->p_cred;
262*0Sstevel@tonic-gate 	p->p_cred = newcred;
263*0Sstevel@tonic-gate 	mutex_exit(&p->p_crlock);
264*0Sstevel@tonic-gate 	crfree(oldcred);
265*0Sstevel@tonic-gate 
266*0Sstevel@tonic-gate 	mutex_enter(&p->p_lock);
267*0Sstevel@tonic-gate 	return (0);
268*0Sstevel@tonic-gate 
269*0Sstevel@tonic-gate err:
270*0Sstevel@tonic-gate 	crfree(newcred);
271*0Sstevel@tonic-gate 	mutex_enter(&p->p_lock);
272*0Sstevel@tonic-gate 	return (err);
273*0Sstevel@tonic-gate }
274*0Sstevel@tonic-gate 
275*0Sstevel@tonic-gate priv_impl_info_t
276*0Sstevel@tonic-gate *priv_hold_implinfo(void)
277*0Sstevel@tonic-gate {
278*0Sstevel@tonic-gate 	rw_enter(&privinfo_lock, RW_READER);
279*0Sstevel@tonic-gate 	return (priv_info);
280*0Sstevel@tonic-gate }
281*0Sstevel@tonic-gate 
282*0Sstevel@tonic-gate void
283*0Sstevel@tonic-gate priv_release_implinfo(void)
284*0Sstevel@tonic-gate {
285*0Sstevel@tonic-gate 	rw_exit(&privinfo_lock);
286*0Sstevel@tonic-gate }
287*0Sstevel@tonic-gate 
288*0Sstevel@tonic-gate size_t
289*0Sstevel@tonic-gate priv_get_implinfo_size(void)
290*0Sstevel@tonic-gate {
291*0Sstevel@tonic-gate 	return (privinfosize);
292*0Sstevel@tonic-gate }
293*0Sstevel@tonic-gate 
294*0Sstevel@tonic-gate 
295*0Sstevel@tonic-gate /*
296*0Sstevel@tonic-gate  * Return the nth privilege set
297*0Sstevel@tonic-gate  */
298*0Sstevel@tonic-gate const priv_set_t *
299*0Sstevel@tonic-gate priv_getset(const cred_t *cr, int set)
300*0Sstevel@tonic-gate {
301*0Sstevel@tonic-gate 	ASSERT(PRIV_VALIDSET(set));
302*0Sstevel@tonic-gate 
303*0Sstevel@tonic-gate 	if ((CR_FLAGS(cr) & PRIV_AWARE) == 0)
304*0Sstevel@tonic-gate 		switch (set) {
305*0Sstevel@tonic-gate 		case PRIV_EFFECTIVE:
306*0Sstevel@tonic-gate 			return (&CR_OEPRIV(cr));
307*0Sstevel@tonic-gate 		case PRIV_PERMITTED:
308*0Sstevel@tonic-gate 			return (&CR_OPPRIV(cr));
309*0Sstevel@tonic-gate 		}
310*0Sstevel@tonic-gate 	return (&CR_PRIVS(cr)->crprivs[set]);
311*0Sstevel@tonic-gate }
312*0Sstevel@tonic-gate 
313*0Sstevel@tonic-gate /*
314*0Sstevel@tonic-gate  * Buf must be allocated by caller and contain sufficient space to
315*0Sstevel@tonic-gate  * contain all additional info structures using priv_info.priv_infosize.
316*0Sstevel@tonic-gate  * The buffer must be properly aligned.
317*0Sstevel@tonic-gate  */
318*0Sstevel@tonic-gate /*ARGSUSED*/
319*0Sstevel@tonic-gate void
320*0Sstevel@tonic-gate priv_getinfo(const cred_t *cr, void *buf)
321*0Sstevel@tonic-gate {
322*0Sstevel@tonic-gate 	struct priv_info_uint *ii;
323*0Sstevel@tonic-gate 
324*0Sstevel@tonic-gate 	ii = buf;
325*0Sstevel@tonic-gate 	ii->val = CR_FLAGS(cr);
326*0Sstevel@tonic-gate 	ii->info.priv_info_size = (uint32_t)sizeof (*ii);
327*0Sstevel@tonic-gate 	ii->info.priv_info_type = PRIV_INFO_FLAGS;
328*0Sstevel@tonic-gate }
329*0Sstevel@tonic-gate 
330*0Sstevel@tonic-gate int
331*0Sstevel@tonic-gate priv_getbyname(const char *name, uint_t flag)
332*0Sstevel@tonic-gate {
333*0Sstevel@tonic-gate 	int i;
334*0Sstevel@tonic-gate 	int wheld = 0;
335*0Sstevel@tonic-gate 	int len;
336*0Sstevel@tonic-gate 	char *p;
337*0Sstevel@tonic-gate 
338*0Sstevel@tonic-gate 	if (flag != 0 && flag != PRIV_ALLOC)
339*0Sstevel@tonic-gate 		return (-EINVAL);
340*0Sstevel@tonic-gate 
341*0Sstevel@tonic-gate 	if (strncasecmp(name, "priv_", 5) == 0)
342*0Sstevel@tonic-gate 		name += 5;
343*0Sstevel@tonic-gate 
344*0Sstevel@tonic-gate 	rw_enter(&privinfo_lock, RW_READER);
345*0Sstevel@tonic-gate rescan:
346*0Sstevel@tonic-gate 	for (i = 0; i < nprivs; i++)
347*0Sstevel@tonic-gate 		if (strcasecmp(priv_names[i], name) == 0) {
348*0Sstevel@tonic-gate 			rw_exit(&privinfo_lock);
349*0Sstevel@tonic-gate 			return (i);
350*0Sstevel@tonic-gate 		}
351*0Sstevel@tonic-gate 
352*0Sstevel@tonic-gate 
353*0Sstevel@tonic-gate 	if (!wheld) {
354*0Sstevel@tonic-gate 		if (!(flag & PRIV_ALLOC)) {
355*0Sstevel@tonic-gate 			rw_exit(&privinfo_lock);
356*0Sstevel@tonic-gate 			return (-EINVAL);
357*0Sstevel@tonic-gate 		}
358*0Sstevel@tonic-gate 
359*0Sstevel@tonic-gate 		/* check length, validity and available space */
360*0Sstevel@tonic-gate 		len = strlen(name) + 1;
361*0Sstevel@tonic-gate 
362*0Sstevel@tonic-gate 		if (len > PRIVNAME_MAX) {
363*0Sstevel@tonic-gate 			rw_exit(&privinfo_lock);
364*0Sstevel@tonic-gate 			return (-ENAMETOOLONG);
365*0Sstevel@tonic-gate 		}
366*0Sstevel@tonic-gate 
367*0Sstevel@tonic-gate 		for (p = (char *)name; *p != '\0'; p++) {
368*0Sstevel@tonic-gate 			char c = *p;
369*0Sstevel@tonic-gate 
370*0Sstevel@tonic-gate 			if (!((c >= 'A' && c <= 'Z') ||
371*0Sstevel@tonic-gate 			    (c >= 'a' && c <= 'z') ||
372*0Sstevel@tonic-gate 			    (c >= '0' && c <= '9') ||
373*0Sstevel@tonic-gate 			    c == '_')) {
374*0Sstevel@tonic-gate 				rw_exit(&privinfo_lock);
375*0Sstevel@tonic-gate 				return (-EINVAL);
376*0Sstevel@tonic-gate 			}
377*0Sstevel@tonic-gate 		}
378*0Sstevel@tonic-gate 
379*0Sstevel@tonic-gate 		if (!rw_tryupgrade(&privinfo_lock)) {
380*0Sstevel@tonic-gate 			rw_exit(&privinfo_lock);
381*0Sstevel@tonic-gate 			rw_enter(&privinfo_lock, RW_WRITER);
382*0Sstevel@tonic-gate 			wheld = 1;
383*0Sstevel@tonic-gate 			/* Someone may have added our privilege */
384*0Sstevel@tonic-gate 			goto rescan;
385*0Sstevel@tonic-gate 		}
386*0Sstevel@tonic-gate 	}
387*0Sstevel@tonic-gate 
388*0Sstevel@tonic-gate 	if (nprivs == MAX_PRIVILEGE || len + privbytes > maxprivbytes) {
389*0Sstevel@tonic-gate 		rw_exit(&privinfo_lock);
390*0Sstevel@tonic-gate 		return (-ENOMEM);
391*0Sstevel@tonic-gate 	}
392*0Sstevel@tonic-gate 
393*0Sstevel@tonic-gate 	priv_names[i] = p = priv_str + privbytes;
394*0Sstevel@tonic-gate 
395*0Sstevel@tonic-gate 	bcopy(name, p, len);
396*0Sstevel@tonic-gate 
397*0Sstevel@tonic-gate 	/* make the priv_names[i] and privilege name globally visible */
398*0Sstevel@tonic-gate 	membar_producer();
399*0Sstevel@tonic-gate 
400*0Sstevel@tonic-gate 	/* adjust priv count and bytes count */
401*0Sstevel@tonic-gate 	priv_ninfo->cnt = priv_info->priv_max = ++nprivs;
402*0Sstevel@tonic-gate 	privbytes += len;
403*0Sstevel@tonic-gate 
404*0Sstevel@tonic-gate 	rw_exit(&privinfo_lock);
405*0Sstevel@tonic-gate 	return (i);
406*0Sstevel@tonic-gate }
407*0Sstevel@tonic-gate 
408*0Sstevel@tonic-gate /*
409*0Sstevel@tonic-gate  * We can't afford locking the privileges here because of the locations
410*0Sstevel@tonic-gate  * we call this from; so we make sure that the privileges table
411*0Sstevel@tonic-gate  * is visible to us; it is made visible before the value of nprivs is
412*0Sstevel@tonic-gate  * updated.
413*0Sstevel@tonic-gate  */
414*0Sstevel@tonic-gate const char *
415*0Sstevel@tonic-gate priv_getbynum(int priv)
416*0Sstevel@tonic-gate {
417*0Sstevel@tonic-gate 	int maxpriv = nprivs;
418*0Sstevel@tonic-gate 
419*0Sstevel@tonic-gate 	membar_consumer();
420*0Sstevel@tonic-gate 
421*0Sstevel@tonic-gate 	if (priv >= 0 && priv < maxpriv)
422*0Sstevel@tonic-gate 		return (priv_names[priv]);
423*0Sstevel@tonic-gate 
424*0Sstevel@tonic-gate 	return (NULL);
425*0Sstevel@tonic-gate }
426*0Sstevel@tonic-gate 
427*0Sstevel@tonic-gate const char *
428*0Sstevel@tonic-gate priv_getsetbynum(int setno)
429*0Sstevel@tonic-gate {
430*0Sstevel@tonic-gate 	if (!PRIV_VALIDSET(setno))
431*0Sstevel@tonic-gate 		return (NULL);
432*0Sstevel@tonic-gate 
433*0Sstevel@tonic-gate 	return (priv_setnames[setno]);
434*0Sstevel@tonic-gate }
435*0Sstevel@tonic-gate 
436*0Sstevel@tonic-gate /*
437*0Sstevel@tonic-gate  * Privilege sanity checking when setting: E <= P.
438*0Sstevel@tonic-gate  */
439*0Sstevel@tonic-gate static boolean_t
440*0Sstevel@tonic-gate priv_valid(const cred_t *cr)
441*0Sstevel@tonic-gate {
442*0Sstevel@tonic-gate 	return (priv_issubset(&CR_EPRIV(cr), &CR_PPRIV(cr)));
443*0Sstevel@tonic-gate }
444*0Sstevel@tonic-gate 
445*0Sstevel@tonic-gate /*
446*0Sstevel@tonic-gate  * Privilege manipulation functions
447*0Sstevel@tonic-gate  *
448*0Sstevel@tonic-gate  * Without knowing the details of the privilege set implementation,
449*0Sstevel@tonic-gate  * opaque pointers can be used to manipulate sets at will.
450*0Sstevel@tonic-gate  */
451*0Sstevel@tonic-gate void
452*0Sstevel@tonic-gate priv_emptyset(priv_set_t *set)
453*0Sstevel@tonic-gate {
454*0Sstevel@tonic-gate 	bzero(set, sizeof (*set));
455*0Sstevel@tonic-gate }
456*0Sstevel@tonic-gate 
457*0Sstevel@tonic-gate void
458*0Sstevel@tonic-gate priv_fillset(priv_set_t *set)
459*0Sstevel@tonic-gate {
460*0Sstevel@tonic-gate 	int i;
461*0Sstevel@tonic-gate 
462*0Sstevel@tonic-gate 	/* memset? */
463*0Sstevel@tonic-gate 	for (i = 0; i < PRIV_SETSIZE; i++)
464*0Sstevel@tonic-gate 		set->pbits[i] = ~(priv_chunk_t)0;
465*0Sstevel@tonic-gate }
466*0Sstevel@tonic-gate 
467*0Sstevel@tonic-gate void
468*0Sstevel@tonic-gate priv_addset(priv_set_t *set, int priv)
469*0Sstevel@tonic-gate {
470*0Sstevel@tonic-gate 	ASSERT(priv >= 0 && priv < MAX_PRIVILEGE);
471*0Sstevel@tonic-gate 	__PRIV_ASSERT(set, priv);
472*0Sstevel@tonic-gate }
473*0Sstevel@tonic-gate 
474*0Sstevel@tonic-gate void
475*0Sstevel@tonic-gate priv_delset(priv_set_t *set, int priv)
476*0Sstevel@tonic-gate {
477*0Sstevel@tonic-gate 	ASSERT(priv >= 0 && priv < MAX_PRIVILEGE);
478*0Sstevel@tonic-gate 	__PRIV_CLEAR(set, priv);
479*0Sstevel@tonic-gate }
480*0Sstevel@tonic-gate 
481*0Sstevel@tonic-gate boolean_t
482*0Sstevel@tonic-gate priv_ismember(const priv_set_t *set, int priv)
483*0Sstevel@tonic-gate {
484*0Sstevel@tonic-gate 	ASSERT(priv >= 0 && priv < MAX_PRIVILEGE);
485*0Sstevel@tonic-gate 	return (__PRIV_ISASSERT(set, priv) ? B_TRUE : B_FALSE);
486*0Sstevel@tonic-gate }
487*0Sstevel@tonic-gate 
488*0Sstevel@tonic-gate #define	PRIV_TEST_BODY(test) \
489*0Sstevel@tonic-gate 	int i; \
490*0Sstevel@tonic-gate \
491*0Sstevel@tonic-gate 	for (i = 0; i < PRIV_SETSIZE; i++) \
492*0Sstevel@tonic-gate 		if (!(test)) \
493*0Sstevel@tonic-gate 			return (B_FALSE); \
494*0Sstevel@tonic-gate \
495*0Sstevel@tonic-gate 	return (B_TRUE)
496*0Sstevel@tonic-gate 
497*0Sstevel@tonic-gate boolean_t
498*0Sstevel@tonic-gate priv_isequalset(const priv_set_t *a, const priv_set_t *b)
499*0Sstevel@tonic-gate {
500*0Sstevel@tonic-gate 	return ((boolean_t)(bcmp(a, b, sizeof (*a)) == 0));
501*0Sstevel@tonic-gate }
502*0Sstevel@tonic-gate 
503*0Sstevel@tonic-gate boolean_t
504*0Sstevel@tonic-gate priv_isemptyset(const priv_set_t *set)
505*0Sstevel@tonic-gate {
506*0Sstevel@tonic-gate 	PRIV_TEST_BODY(set->pbits[i] == 0);
507*0Sstevel@tonic-gate }
508*0Sstevel@tonic-gate 
509*0Sstevel@tonic-gate boolean_t
510*0Sstevel@tonic-gate priv_isfullset(const priv_set_t *set)
511*0Sstevel@tonic-gate {
512*0Sstevel@tonic-gate 	PRIV_TEST_BODY(set->pbits[i] == ~(priv_chunk_t)0);
513*0Sstevel@tonic-gate }
514*0Sstevel@tonic-gate 
515*0Sstevel@tonic-gate /*
516*0Sstevel@tonic-gate  * Return true if a is a subset of b
517*0Sstevel@tonic-gate  */
518*0Sstevel@tonic-gate boolean_t
519*0Sstevel@tonic-gate priv_issubset(const priv_set_t *a, const priv_set_t *b)
520*0Sstevel@tonic-gate {
521*0Sstevel@tonic-gate 	PRIV_TEST_BODY((a->pbits[i] | b->pbits[i]) == b->pbits[i]);
522*0Sstevel@tonic-gate }
523*0Sstevel@tonic-gate 
524*0Sstevel@tonic-gate #define	PRIV_CHANGE_BODY(a, op, b) \
525*0Sstevel@tonic-gate 	int i; \
526*0Sstevel@tonic-gate \
527*0Sstevel@tonic-gate 	for (i = 0; i < PRIV_SETSIZE; i++) \
528*0Sstevel@tonic-gate 		a->pbits[i] op b->pbits[i]
529*0Sstevel@tonic-gate 
530*0Sstevel@tonic-gate /* B = A ^ B */
531*0Sstevel@tonic-gate void
532*0Sstevel@tonic-gate priv_intersect(const priv_set_t *a, priv_set_t *b)
533*0Sstevel@tonic-gate {
534*0Sstevel@tonic-gate 	/* CSTYLED */
535*0Sstevel@tonic-gate 	PRIV_CHANGE_BODY(b, &=, a);
536*0Sstevel@tonic-gate }
537*0Sstevel@tonic-gate 
538*0Sstevel@tonic-gate /* B = A v B */
539*0Sstevel@tonic-gate void
540*0Sstevel@tonic-gate priv_union(const priv_set_t *a, priv_set_t *b)
541*0Sstevel@tonic-gate {
542*0Sstevel@tonic-gate 	/* CSTYLED */
543*0Sstevel@tonic-gate 	PRIV_CHANGE_BODY(b, |=, a);
544*0Sstevel@tonic-gate }
545*0Sstevel@tonic-gate 
546*0Sstevel@tonic-gate /* A = ! A */
547*0Sstevel@tonic-gate void
548*0Sstevel@tonic-gate priv_inverse(priv_set_t *a)
549*0Sstevel@tonic-gate {
550*0Sstevel@tonic-gate 	PRIV_CHANGE_BODY(a, = ~, a);
551*0Sstevel@tonic-gate }
552*0Sstevel@tonic-gate 
553*0Sstevel@tonic-gate /*
554*0Sstevel@tonic-gate  * Can the source cred act on the target credential?
555*0Sstevel@tonic-gate  *
556*0Sstevel@tonic-gate  * We will you allow to gain uids this way but not privileges.
557*0Sstevel@tonic-gate  */
558*0Sstevel@tonic-gate int
559*0Sstevel@tonic-gate priv_proc_cred_perm(const cred_t *scr, proc_t *tp, cred_t **pcr, int mode)
560*0Sstevel@tonic-gate {
561*0Sstevel@tonic-gate 	const priv_set_t *eset;
562*0Sstevel@tonic-gate 	int idsmatch;
563*0Sstevel@tonic-gate 	cred_t *tcr;
564*0Sstevel@tonic-gate 	int res = 0;
565*0Sstevel@tonic-gate 
566*0Sstevel@tonic-gate 	/* prevent the cred from going away */
567*0Sstevel@tonic-gate 	mutex_enter(&tp->p_crlock);
568*0Sstevel@tonic-gate 	crhold(tcr = tp->p_cred);
569*0Sstevel@tonic-gate 	mutex_exit(&tp->p_crlock);
570*0Sstevel@tonic-gate 
571*0Sstevel@tonic-gate 	if (scr == tcr)
572*0Sstevel@tonic-gate 		goto out;
573*0Sstevel@tonic-gate 
574*0Sstevel@tonic-gate 	idsmatch = (scr->cr_uid == tcr->cr_uid &&
575*0Sstevel@tonic-gate 		    scr->cr_uid == tcr->cr_ruid &&
576*0Sstevel@tonic-gate 		    scr->cr_uid == tcr->cr_suid &&
577*0Sstevel@tonic-gate 		    scr->cr_gid == tcr->cr_gid &&
578*0Sstevel@tonic-gate 		    scr->cr_gid == tcr->cr_rgid &&
579*0Sstevel@tonic-gate 		    scr->cr_gid == tcr->cr_sgid &&
580*0Sstevel@tonic-gate 		    !(tp->p_flag & SNOCD));
581*0Sstevel@tonic-gate 
582*0Sstevel@tonic-gate 	/*
583*0Sstevel@tonic-gate 	 * Source credential must have the proc_zone privilege if referencing
584*0Sstevel@tonic-gate 	 * a process in another zone.
585*0Sstevel@tonic-gate 	 */
586*0Sstevel@tonic-gate 	if (scr->cr_zone != tcr->cr_zone && secpolicy_proc_zone(scr) != 0) {
587*0Sstevel@tonic-gate 		res = EACCES;
588*0Sstevel@tonic-gate 		goto out;
589*0Sstevel@tonic-gate 	}
590*0Sstevel@tonic-gate 
591*0Sstevel@tonic-gate 	if (!(mode & VWRITE)) {
592*0Sstevel@tonic-gate 		if (!idsmatch && secpolicy_proc_owner(scr, tcr, 0) != 0)
593*0Sstevel@tonic-gate 			res = EACCES;
594*0Sstevel@tonic-gate 		goto out;
595*0Sstevel@tonic-gate 	}
596*0Sstevel@tonic-gate 
597*0Sstevel@tonic-gate 	/*
598*0Sstevel@tonic-gate 	 * For writing, the effective set of scr must dominate all sets of tcr,
599*0Sstevel@tonic-gate 	 * We test Pt <= Es (Et <= Pt so no need to test) and It <= Es
600*0Sstevel@tonic-gate 	 * The Limit set of scr must be a superset of the limitset of
601*0Sstevel@tonic-gate 	 * tcr.
602*0Sstevel@tonic-gate 	 */
603*0Sstevel@tonic-gate 	eset = &CR_OEPRIV(scr);
604*0Sstevel@tonic-gate 
605*0Sstevel@tonic-gate 	if (!priv_issubset(&CR_IPRIV(tcr), eset) ||
606*0Sstevel@tonic-gate 	    !priv_issubset(&CR_OPPRIV(tcr), eset) ||
607*0Sstevel@tonic-gate 	    !priv_issubset(&CR_LPRIV(tcr), &CR_LPRIV(scr)) ||
608*0Sstevel@tonic-gate 	    !idsmatch && secpolicy_proc_owner(scr, tcr, mode) != 0)
609*0Sstevel@tonic-gate 		res = EACCES;
610*0Sstevel@tonic-gate 
611*0Sstevel@tonic-gate out:
612*0Sstevel@tonic-gate 	if (res == 0 && pcr != NULL)
613*0Sstevel@tonic-gate 		*pcr = tcr;
614*0Sstevel@tonic-gate 	else
615*0Sstevel@tonic-gate 		crfree(tcr);
616*0Sstevel@tonic-gate 	return (res);
617*0Sstevel@tonic-gate }
618*0Sstevel@tonic-gate 
619*0Sstevel@tonic-gate /*
620*0Sstevel@tonic-gate  * Set the privilege aware bit, adding L to E/P if
621*0Sstevel@tonic-gate  * necessasry.
622*0Sstevel@tonic-gate  */
623*0Sstevel@tonic-gate void
624*0Sstevel@tonic-gate priv_set_PA(cred_t *cr)
625*0Sstevel@tonic-gate {
626*0Sstevel@tonic-gate 	ASSERT(cr->cr_ref <= 2);
627*0Sstevel@tonic-gate 
628*0Sstevel@tonic-gate 	if (CR_FLAGS(cr) & PRIV_AWARE)
629*0Sstevel@tonic-gate 		return;
630*0Sstevel@tonic-gate 
631*0Sstevel@tonic-gate 	CR_FLAGS(cr) |= PRIV_AWARE;
632*0Sstevel@tonic-gate 
633*0Sstevel@tonic-gate 	if (cr->cr_uid == 0)
634*0Sstevel@tonic-gate 		priv_union(&CR_LPRIV(cr), &CR_EPRIV(cr));
635*0Sstevel@tonic-gate 
636*0Sstevel@tonic-gate 	if (cr->cr_uid == 0 || cr->cr_suid == 0 || cr->cr_ruid == 0)
637*0Sstevel@tonic-gate 		priv_union(&CR_LPRIV(cr), &CR_PPRIV(cr));
638*0Sstevel@tonic-gate }
639*0Sstevel@tonic-gate 
640*0Sstevel@tonic-gate boolean_t
641*0Sstevel@tonic-gate priv_can_clear_PA(const cred_t *cr)
642*0Sstevel@tonic-gate {
643*0Sstevel@tonic-gate 	/*
644*0Sstevel@tonic-gate 	 * We can clear PA in the following cases:
645*0Sstevel@tonic-gate 	 *
646*0Sstevel@tonic-gate 	 * None of the uids are 0.
647*0Sstevel@tonic-gate 	 * Any uid == 0 and P == L and (Euid != 0 or E == L)
648*0Sstevel@tonic-gate 	 */
649*0Sstevel@tonic-gate 	return ((cr->cr_suid != 0 && cr->cr_ruid != 0 && cr->cr_uid != 0) ||
650*0Sstevel@tonic-gate 	    priv_isequalset(&CR_PPRIV(cr), &CR_LPRIV(cr)) &&
651*0Sstevel@tonic-gate 	    (cr->cr_uid != 0 || priv_isequalset(&CR_EPRIV(cr), &CR_LPRIV(cr))));
652*0Sstevel@tonic-gate }
653*0Sstevel@tonic-gate 
654*0Sstevel@tonic-gate /*
655*0Sstevel@tonic-gate  * Clear privilege aware bit if it is an idempotent operation and by
656*0Sstevel@tonic-gate  * clearing it the process cannot get to uid 0 and all privileges.
657*0Sstevel@tonic-gate  *
658*0Sstevel@tonic-gate  * This function should be called with caution as it may cause "E" to be
659*0Sstevel@tonic-gate  * lost once a processes assumes euid 0 again.
660*0Sstevel@tonic-gate  */
661*0Sstevel@tonic-gate void
662*0Sstevel@tonic-gate priv_adjust_PA(cred_t *cr)
663*0Sstevel@tonic-gate {
664*0Sstevel@tonic-gate 	ASSERT(cr->cr_ref <= 2);
665*0Sstevel@tonic-gate 
666*0Sstevel@tonic-gate 	if (!(CR_FLAGS(cr) & PRIV_AWARE) ||
667*0Sstevel@tonic-gate 	    !priv_can_clear_PA(cr))
668*0Sstevel@tonic-gate 		return;
669*0Sstevel@tonic-gate 
670*0Sstevel@tonic-gate 	if (CR_FLAGS(cr) & PRIV_AWARE_INHERIT)
671*0Sstevel@tonic-gate 		return;
672*0Sstevel@tonic-gate 
673*0Sstevel@tonic-gate 	/*
674*0Sstevel@tonic-gate 	 * We now need to adjust P/E in those cases when uids
675*0Sstevel@tonic-gate 	 * are zero; the rules are P' = I & L, E' = I & L;
676*0Sstevel@tonic-gate 	 * but since P = L and E = L, we can use P &= I, E &= I,
677*0Sstevel@tonic-gate 	 * depending on which uids are 0.
678*0Sstevel@tonic-gate 	 */
679*0Sstevel@tonic-gate 	if (cr->cr_suid == 0 || cr->cr_ruid == 0 || cr->cr_uid == 0) {
680*0Sstevel@tonic-gate 		if (cr->cr_uid == 0)
681*0Sstevel@tonic-gate 			priv_intersect(&CR_IPRIV(cr), &CR_EPRIV(cr));
682*0Sstevel@tonic-gate 		priv_intersect(&CR_IPRIV(cr), &CR_PPRIV(cr));
683*0Sstevel@tonic-gate 	}
684*0Sstevel@tonic-gate 
685*0Sstevel@tonic-gate 	CR_FLAGS(cr) &= ~PRIV_AWARE;
686*0Sstevel@tonic-gate }
687