/*
 * 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 (c) 2013, Ira Cooper.  All rights reserved.
 * Copyright 2020 Nexenta by DDN, Inc. All rights reserved.
 */
/*
 * Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
 */

/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved   */

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

#include <sys/types.h>
#include <sys/sysmacros.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/cred_impl.h>
#include <sys/policy.h>
#include <sys/vnode.h>
#include <sys/errno.h>
#include <sys/kmem.h>
#include <sys/user.h>
#include <sys/proc.h>
#include <sys/syscall.h>
#include <sys/debug.h>
#include <sys/atomic.h>
#include <sys/ucred.h>
#include <sys/prsystm.h>
#include <sys/modctl.h>
#include <sys/avl.h>
#include <sys/door.h>
#include <c2/audit.h>
#include <sys/zone.h>
#include <sys/tsol/label.h>
#include <sys/sid.h>
#include <sys/idmap.h>
#include <sys/klpd.h>
#include <sys/varargs.h>
#include <sys/sysconf.h>
#include <util/qsort.h>


/* Ephemeral IDs Zones specific data */
typedef struct ephemeral_zsd {
        uid_t           min_uid;
        uid_t           last_uid;
        gid_t           min_gid;
        gid_t           last_gid;
        kmutex_t        eph_lock;
        cred_t          *eph_nobody;
} ephemeral_zsd_t;

static void crgrphold(credgrp_t *);

#define CREDGRPSZ(ngrp) (sizeof (credgrp_t) + ((ngrp - 1) * sizeof (gid_t)))

static kmutex_t         ephemeral_zone_mutex;
static zone_key_t       ephemeral_zone_key;

static struct kmem_cache *cred_cache;
static size_t           crsize = 0;
static int              audoff = 0;
uint32_t                ucredsize;
cred_t                  *kcred;
static cred_t           *dummycr;

int rstlink;            /* link(2) restricted to files owned by user? */

static int get_c2audit_load(void);

#define CR_AUINFO(c)    (auditinfo_addr_t *)((audoff == 0) ? NULL : \
                            ((char *)(c)) + audoff)

#define REMOTE_PEER_CRED(c)     ((c)->cr_gid == -1)

#define BIN_GROUP_SEARCH_CUTOFF 16

static boolean_t hasephids = B_FALSE;

static ephemeral_zsd_t *
get_ephemeral_zsd(zone_t *zone)
{
        ephemeral_zsd_t *eph_zsd;

        eph_zsd = zone_getspecific(ephemeral_zone_key, zone);
        if (eph_zsd != NULL) {
                return (eph_zsd);
        }

        mutex_enter(&ephemeral_zone_mutex);
        eph_zsd = zone_getspecific(ephemeral_zone_key, zone);
        if (eph_zsd == NULL) {
                eph_zsd = kmem_zalloc(sizeof (ephemeral_zsd_t), KM_SLEEP);
                eph_zsd->min_uid = MAXUID;
                eph_zsd->last_uid = IDMAP_WK__MAX_UID;
                eph_zsd->min_gid = MAXUID;
                eph_zsd->last_gid = IDMAP_WK__MAX_GID;
                mutex_init(&eph_zsd->eph_lock, NULL, MUTEX_DEFAULT, NULL);

                /*
                 * nobody is used to map SID containing CRs.
                 */
                eph_zsd->eph_nobody = crdup(zone->zone_kcred);
                (void) crsetugid(eph_zsd->eph_nobody, UID_NOBODY, GID_NOBODY);
                CR_FLAGS(eph_zsd->eph_nobody) = 0;
                eph_zsd->eph_nobody->cr_zone = zone;

                (void) zone_setspecific(ephemeral_zone_key, zone, eph_zsd);
        }
        mutex_exit(&ephemeral_zone_mutex);
        return (eph_zsd);
}

static cred_t *crdup_flags(const cred_t *, int);
static cred_t *cralloc_flags(int);

/*
 * This function is called when a zone is destroyed
 */
static void
/* ARGSUSED */
destroy_ephemeral_zsd(zoneid_t zone_id, void *arg)
{
        ephemeral_zsd_t *eph_zsd = arg;
        if (eph_zsd != NULL) {
                mutex_destroy(&eph_zsd->eph_lock);
                crfree(eph_zsd->eph_nobody);
                kmem_free(eph_zsd, sizeof (ephemeral_zsd_t));
        }
}



/*
 * Initialize credentials data structures.
 */

void
cred_init(void)
{
        priv_init();

        crsize = sizeof (cred_t);

        if (get_c2audit_load() > 0) {
#ifdef _LP64
                /* assure audit context is 64-bit aligned */
                audoff = (crsize +
                    sizeof (int64_t) - 1) & ~(sizeof (int64_t) - 1);
#else   /* _LP64 */
                audoff = crsize;
#endif  /* _LP64 */
                crsize = audoff + sizeof (auditinfo_addr_t);
                crsize = (crsize + sizeof (int) - 1) & ~(sizeof (int) - 1);
        }

        cred_cache = kmem_cache_create("cred_cache", crsize, 0,
            NULL, NULL, NULL, NULL, NULL, 0);

        /*
         * dummycr is used to copy initial state for creds.
         */
        dummycr = cralloc();
        bzero(dummycr, crsize);
        dummycr->cr_ref = 1;
        dummycr->cr_uid = (uid_t)-1;
        dummycr->cr_gid = (gid_t)-1;
        dummycr->cr_ruid = (uid_t)-1;
        dummycr->cr_rgid = (gid_t)-1;
        dummycr->cr_suid = (uid_t)-1;
        dummycr->cr_sgid = (gid_t)-1;


        /*
         * kcred is used by anything that needs all privileges; it's
         * also the template used for crget as it has all the compatible
         * sets filled in.
         */
        kcred = cralloc();

        bzero(kcred, crsize);
        kcred->cr_ref = 1;

        /* kcred is never freed, so we don't need zone_cred_hold here */
        kcred->cr_zone = &zone0;

        priv_fillset(&CR_LPRIV(kcred));
        CR_IPRIV(kcred) = *priv_basic;

        priv_addset(&CR_IPRIV(kcred), PRIV_PROC_SECFLAGS);

        /* Not a basic privilege, if chown is not restricted add it to I0 */
        if (!rstchown)
                priv_addset(&CR_IPRIV(kcred), PRIV_FILE_CHOWN_SELF);

        /* Basic privilege, if link is restricted remove it from I0 */
        if (rstlink)
                priv_delset(&CR_IPRIV(kcred), PRIV_FILE_LINK_ANY);

        CR_EPRIV(kcred) = CR_PPRIV(kcred) = CR_IPRIV(kcred);

        CR_FLAGS(kcred) = NET_MAC_AWARE;

        /*
         * Set up credentials of p0.
         */
        ttoproc(curthread)->p_cred = kcred;
        curthread->t_cred = kcred;

        ucredsize = UCRED_SIZE;

        mutex_init(&ephemeral_zone_mutex, NULL, MUTEX_DEFAULT, NULL);
        zone_key_create(&ephemeral_zone_key, NULL, NULL, destroy_ephemeral_zsd);
}

/*
 * Allocate (nearly) uninitialized cred_t.
 */
static cred_t *
cralloc_flags(int flgs)
{
        cred_t *cr = kmem_cache_alloc(cred_cache, flgs);

        if (cr == NULL)
                return (NULL);

        cr->cr_ref = 1;         /* So we can crfree() */
        cr->cr_zone = NULL;
        cr->cr_label = NULL;
        cr->cr_ksid = NULL;
        cr->cr_klpd = NULL;
        cr->cr_grps = NULL;
        return (cr);
}

cred_t *
cralloc(void)
{
        return (cralloc_flags(KM_SLEEP));
}

/*
 * As cralloc but prepared for ksid change (if appropriate).
 */
cred_t *
cralloc_ksid(void)
{
        cred_t *cr = cralloc();
        if (hasephids)
                cr->cr_ksid = kcrsid_alloc();
        return (cr);
}

/*
 * Allocate a initialized cred structure and crhold() it.
 * Initialized means: all ids 0, group count 0, L=Full, E=P=I=I0
 */
cred_t *
crget(void)
{
        cred_t *cr = kmem_cache_alloc(cred_cache, KM_SLEEP);

        bcopy(zone_kcred(), cr, crsize);
        cr->cr_ref = 1;
        zone_cred_hold(cr->cr_zone);
        if (cr->cr_label)
                label_hold(cr->cr_label);
        ASSERT(cr->cr_klpd == NULL);
        ASSERT(cr->cr_grps == NULL);
        return (cr);
}

/*
 * Broadcast the cred to all the threads in the process.
 * The current thread's credentials can be set right away, but other
 * threads must wait until the start of the next system call or trap.
 * This avoids changing the cred in the middle of a system call.
 *
 * The cred has already been held for the process and the thread (2 holds),
 * and p->p_cred set.
 *
 * p->p_crlock shouldn't be held here, since p_lock must be acquired.
 */
void
crset(proc_t *p, cred_t *cr)
{
        kthread_id_t    t;
        kthread_id_t    first;
        cred_t *oldcr;

        ASSERT(p == curproc);   /* assumes p_lwpcnt can't change */

        /*
         * DTrace accesses t_cred in probe context.  t_cred must always be
         * either NULL, or point to a valid, allocated cred structure.
         */
        t = curthread;
        oldcr = t->t_cred;
        t->t_cred = cr;         /* the cred is held by caller for this thread */
        crfree(oldcr);          /* free the old cred for the thread */

        /*
         * Broadcast to other threads, if any.
         */
        if (p->p_lwpcnt > 1) {
                mutex_enter(&p->p_lock);        /* to keep thread list safe */
                first = curthread;
                for (t = first->t_forw; t != first; t = t->t_forw)
                        t->t_pre_sys = 1; /* so syscall will get new cred */
                mutex_exit(&p->p_lock);
        }
}

/*
 * Put a hold on a cred structure.
 */
void
crhold(cred_t *cr)
{
        ASSERT(cr->cr_ref != 0xdeadbeef && cr->cr_ref != 0);
        atomic_inc_32(&cr->cr_ref);
}

/*
 * Release previous hold on a cred structure.  Free it if refcnt == 0.
 * If cred uses label different from zone label, free it.
 */
void
crfree(cred_t *cr)
{
        ASSERT(cr->cr_ref != 0xdeadbeef && cr->cr_ref != 0);
        if (atomic_dec_32_nv(&cr->cr_ref) == 0) {
                ASSERT(cr != kcred);
                if (cr->cr_label)
                        label_rele(cr->cr_label);
                if (cr->cr_klpd)
                        crklpd_rele(cr->cr_klpd);
                if (cr->cr_zone)
                        zone_cred_rele(cr->cr_zone);
                if (cr->cr_ksid)
                        kcrsid_rele(cr->cr_ksid);
                if (cr->cr_grps)
                        crgrprele(cr->cr_grps);

                kmem_cache_free(cred_cache, cr);
        }
}

/*
 * Copy a cred structure to a new one and free the old one.
 *      The new cred will have two references.  One for the calling process,
 *      and one for the thread.
 */
cred_t *
crcopy(cred_t *cr)
{
        cred_t *newcr;

        newcr = cralloc();
        bcopy(cr, newcr, crsize);
        if (newcr->cr_zone)
                zone_cred_hold(newcr->cr_zone);
        if (newcr->cr_label)
                label_hold(newcr->cr_label);
        if (newcr->cr_ksid)
                kcrsid_hold(newcr->cr_ksid);
        if (newcr->cr_klpd)
                crklpd_hold(newcr->cr_klpd);
        if (newcr->cr_grps)
                crgrphold(newcr->cr_grps);
        crfree(cr);
        newcr->cr_ref = 2;              /* caller gets two references */
        return (newcr);
}

/*
 * Copy a cred structure to a new one and free the old one.
 *      The new cred will have two references.  One for the calling process,
 *      and one for the thread.
 * This variation on crcopy uses a pre-allocated structure for the
 * "new" cred.
 */
void
crcopy_to(cred_t *oldcr, cred_t *newcr)
{
        credsid_t *nkcr = newcr->cr_ksid;

        bcopy(oldcr, newcr, crsize);
        if (newcr->cr_zone)
                zone_cred_hold(newcr->cr_zone);
        if (newcr->cr_label)
                label_hold(newcr->cr_label);
        if (newcr->cr_klpd)
                crklpd_hold(newcr->cr_klpd);
        if (newcr->cr_grps)
                crgrphold(newcr->cr_grps);
        if (nkcr) {
                newcr->cr_ksid = nkcr;
                kcrsidcopy_to(oldcr->cr_ksid, newcr->cr_ksid);
        } else if (newcr->cr_ksid)
                kcrsid_hold(newcr->cr_ksid);
        crfree(oldcr);
        newcr->cr_ref = 2;              /* caller gets two references */
}

/*
 * Dup a cred struct to a new held one.
 *      The old cred is not freed.
 */
static cred_t *
crdup_flags(const cred_t *cr, int flgs)
{
        cred_t *newcr;

        newcr = cralloc_flags(flgs);

        if (newcr == NULL)
                return (NULL);

        bcopy(cr, newcr, crsize);
        if (newcr->cr_zone)
                zone_cred_hold(newcr->cr_zone);
        if (newcr->cr_label)
                label_hold(newcr->cr_label);
        if (newcr->cr_klpd)
                crklpd_hold(newcr->cr_klpd);
        if (newcr->cr_ksid)
                kcrsid_hold(newcr->cr_ksid);
        if (newcr->cr_grps)
                crgrphold(newcr->cr_grps);
        newcr->cr_ref = 1;
        return (newcr);
}

cred_t *
crdup(cred_t *cr)
{
        return (crdup_flags(cr, KM_SLEEP));
}

/*
 * Dup a cred struct to a new held one.
 *      The old cred is not freed.
 * This variation on crdup uses a pre-allocated structure for the
 * "new" cred.
 */
void
crdup_to(cred_t *oldcr, cred_t *newcr)
{
        credsid_t *nkcr = newcr->cr_ksid;

        bcopy(oldcr, newcr, crsize);
        if (newcr->cr_zone)
                zone_cred_hold(newcr->cr_zone);
        if (newcr->cr_label)
                label_hold(newcr->cr_label);
        if (newcr->cr_klpd)
                crklpd_hold(newcr->cr_klpd);
        if (newcr->cr_grps)
                crgrphold(newcr->cr_grps);
        if (nkcr) {
                newcr->cr_ksid = nkcr;
                kcrsidcopy_to(oldcr->cr_ksid, newcr->cr_ksid);
        } else if (newcr->cr_ksid)
                kcrsid_hold(newcr->cr_ksid);
        newcr->cr_ref = 1;
}

/*
 * Return the (held) credentials for the current running process.
 */
cred_t *
crgetcred(void)
{
        cred_t *cr;
        proc_t *p;

        p = ttoproc(curthread);
        mutex_enter(&p->p_crlock);
        crhold(cr = p->p_cred);
        mutex_exit(&p->p_crlock);
        return (cr);
}

/*
 * Backward compatibility check for suser().
 * Accounting flag is now set in the policy functions; auditing is
 * done through use of privilege in the audit trail.
 */
int
suser(cred_t *cr)
{
        return (PRIV_POLICY(cr, PRIV_SYS_SUSER_COMPAT, B_FALSE, EPERM, NULL)
            == 0);
}

/*
 * Determine whether the supplied group id is a member of the group
 * described by the supplied credentials.
 */
int
groupmember(gid_t gid, const cred_t *cr)
{
        if (gid == cr->cr_gid)
                return (1);
        return (supgroupmember(gid, cr));
}

/*
 * As groupmember but only check against the supplemental groups.
 */
int
supgroupmember(gid_t gid, const cred_t *cr)
{
        int hi, lo;
        credgrp_t *grps = cr->cr_grps;
        const gid_t *gp, *endgp;

        if (grps == NULL)
                return (0);

        /* For a small number of groups, use sequentials search. */
        if (grps->crg_ngroups <= BIN_GROUP_SEARCH_CUTOFF) {
                endgp = &grps->crg_groups[grps->crg_ngroups];
                for (gp = grps->crg_groups; gp < endgp; gp++)
                        if (*gp == gid)
                                return (1);
                return (0);
        }

        /* We use binary search when we have many groups. */
        lo = 0;
        hi = grps->crg_ngroups - 1;
        gp = grps->crg_groups;

        do {
                int m = (lo + hi) / 2;

                if (gid > gp[m])
                        lo = m + 1;
                else if (gid < gp[m])
                        hi = m - 1;
                else
                        return (1);
        } while (lo <= hi);

        return (0);
}

/*
 * This function is called to check whether the credentials set
 * "scrp" has permission to act on credentials set "tcrp".  It enforces the
 * permission requirements needed to send a signal to a process.
 * The same requirements are imposed by other system calls, however.
 *
 * The rules are:
 * (1) if the credentials are the same, the check succeeds
 * (2) if the zone ids don't match, and scrp is not in the global zone or
 *     does not have the PRIV_PROC_ZONE privilege, the check fails
 * (3) if the real or effective user id of scrp matches the real or saved
 *     user id of tcrp or scrp has the PRIV_PROC_OWNER privilege, the check
 *     succeeds
 * (4) otherwise, the check fails
 */
int
hasprocperm(const cred_t *tcrp, const cred_t *scrp)
{
        if (scrp == tcrp)
                return (1);
        if (scrp->cr_zone != tcrp->cr_zone &&
            (scrp->cr_zone != global_zone ||
            secpolicy_proc_zone(scrp) != 0))
                return (0);
        if (scrp->cr_uid == tcrp->cr_ruid ||
            scrp->cr_ruid == tcrp->cr_ruid ||
            scrp->cr_uid  == tcrp->cr_suid ||
            scrp->cr_ruid == tcrp->cr_suid ||
            !PRIV_POLICY(scrp, PRIV_PROC_OWNER, B_FALSE, EPERM, "hasprocperm"))
                return (1);
        return (0);
}

/*
 * This interface replaces hasprocperm; it works like hasprocperm but
 * additionally returns success if the proc_t's match
 * It is the preferred interface for most uses.
 * And it will acquire p_crlock itself, so it assert's that it shouldn't
 * be held.
 */
int
prochasprocperm(proc_t *tp, proc_t *sp, const cred_t *scrp)
{
        int rets;
        cred_t *tcrp;

        ASSERT(MUTEX_NOT_HELD(&tp->p_crlock));

        if (tp == sp)
                return (1);

        if (tp->p_sessp != sp->p_sessp && secpolicy_basic_proc(scrp) != 0)
                return (0);

        mutex_enter(&tp->p_crlock);
        crhold(tcrp = tp->p_cred);
        mutex_exit(&tp->p_crlock);
        rets = hasprocperm(tcrp, scrp);
        crfree(tcrp);

        return (rets);
}

/*
 * This routine is used to compare two credentials to determine if
 * they refer to the same "user".  If the pointers are equal, then
 * they must refer to the same user.  Otherwise, the contents of
 * the credentials are compared to see whether they are equivalent.
 *
 * This routine returns 0 if the credentials refer to the same user,
 * 1 if they do not.
 */
int
crcmp(const cred_t *cr1, const cred_t *cr2)
{
        credgrp_t *grp1, *grp2;

        if (cr1 == cr2)
                return (0);

        if (cr1->cr_uid == cr2->cr_uid &&
            cr1->cr_gid == cr2->cr_gid &&
            cr1->cr_ruid == cr2->cr_ruid &&
            cr1->cr_rgid == cr2->cr_rgid &&
            cr1->cr_zone == cr2->cr_zone &&
            ((grp1 = cr1->cr_grps) == (grp2 = cr2->cr_grps) ||
            (grp1 != NULL && grp2 != NULL &&
            grp1->crg_ngroups == grp2->crg_ngroups &&
            bcmp(grp1->crg_groups, grp2->crg_groups,
            grp1->crg_ngroups * sizeof (gid_t)) == 0))) {
                return (!priv_isequalset(&CR_OEPRIV(cr1), &CR_OEPRIV(cr2)));
        }
        return (1);
}

/*
 * Read access functions to cred_t.
 */
uid_t
crgetuid(const cred_t *cr)
{
        return (cr->cr_uid);
}

uid_t
crgetruid(const cred_t *cr)
{
        return (cr->cr_ruid);
}

uid_t
crgetsuid(const cred_t *cr)
{
        return (cr->cr_suid);
}

gid_t
crgetgid(const cred_t *cr)
{
        return (cr->cr_gid);
}

gid_t
crgetrgid(const cred_t *cr)
{
        return (cr->cr_rgid);
}

gid_t
crgetsgid(const cred_t *cr)
{
        return (cr->cr_sgid);
}

const auditinfo_addr_t *
crgetauinfo(const cred_t *cr)
{
        return ((const auditinfo_addr_t *)CR_AUINFO(cr));
}

auditinfo_addr_t *
crgetauinfo_modifiable(cred_t *cr)
{
        return (CR_AUINFO(cr));
}

zoneid_t
crgetzoneid(const cred_t *cr)
{
        return (cr->cr_zone == NULL ?
            (cr->cr_uid == -1 ? (zoneid_t)-1 : GLOBAL_ZONEID) :
            cr->cr_zone->zone_id);
}

projid_t
crgetprojid(const cred_t *cr)
{
        return (cr->cr_projid);
}

zone_t *
crgetzone(const cred_t *cr)
{
        return (cr->cr_zone);
}

struct ts_label_s *
crgetlabel(const cred_t *cr)
{
        return (cr->cr_label ?
            cr->cr_label :
            (cr->cr_zone ? cr->cr_zone->zone_slabel : NULL));
}

boolean_t
crisremote(const cred_t *cr)
{
        return (REMOTE_PEER_CRED(cr));
}

#define BADUID(x, zn)   ((x) != -1 && !VALID_UID((x), (zn)))
#define BADGID(x, zn)   ((x) != -1 && !VALID_GID((x), (zn)))

int
crsetresuid(cred_t *cr, uid_t r, uid_t e, uid_t s)
{
        zone_t  *zone = crgetzone(cr);

        ASSERT(cr->cr_ref <= 2);

        if (BADUID(r, zone) || BADUID(e, zone) || BADUID(s, zone))
                return (-1);

        if (r != -1)
                cr->cr_ruid = r;
        if (e != -1)
                cr->cr_uid = e;
        if (s != -1)
                cr->cr_suid = s;

        return (0);
}

int
crsetresgid(cred_t *cr, gid_t r, gid_t e, gid_t s)
{
        zone_t  *zone = crgetzone(cr);

        ASSERT(cr->cr_ref <= 2);

        if (BADGID(r, zone) || BADGID(e, zone) || BADGID(s, zone))
                return (-1);

        if (r != -1)
                cr->cr_rgid = r;
        if (e != -1)
                cr->cr_gid = e;
        if (s != -1)
                cr->cr_sgid = s;

        return (0);
}

int
crsetugid(cred_t *cr, uid_t uid, gid_t gid)
{
        zone_t  *zone = crgetzone(cr);

        ASSERT(cr->cr_ref <= 2);

        if (!VALID_UID(uid, zone) || !VALID_GID(gid, zone))
                return (-1);

        cr->cr_uid = cr->cr_ruid = cr->cr_suid = uid;
        cr->cr_gid = cr->cr_rgid = cr->cr_sgid = gid;

        return (0);
}

static int
gidcmp(const void *v1, const void *v2)
{
        gid_t g1 = *(gid_t *)v1;
        gid_t g2 = *(gid_t *)v2;

        if (g1 < g2)
                return (-1);
        else if (g1 > g2)
                return (1);
        else
                return (0);
}

int
crsetgroups(cred_t *cr, int n, gid_t *grp)
{
        ASSERT(cr->cr_ref <= 2);

        if (n > ngroups_max || n < 0)
                return (-1);

        if (cr->cr_grps != NULL)
                crgrprele(cr->cr_grps);

        if (n > 0) {
                cr->cr_grps = kmem_alloc(CREDGRPSZ(n), KM_SLEEP);
                bcopy(grp, cr->cr_grps->crg_groups, n * sizeof (gid_t));
                cr->cr_grps->crg_ref = 1;
                cr->cr_grps->crg_ngroups = n;
                qsort(cr->cr_grps->crg_groups, n, sizeof (gid_t), gidcmp);
        } else {
                cr->cr_grps = NULL;
        }

        return (0);
}

void
crsetprojid(cred_t *cr, projid_t projid)
{
        ASSERT(projid >= 0 && projid <= MAXPROJID);
        cr->cr_projid = projid;
}

/*
 * This routine returns the pointer to the first element of the crg_groups
 * array.  It can move around in an implementation defined way.
 * Note that when we have no grouplist, we return one element but the
 * caller should never reference it.
 */
const gid_t *
crgetgroups(const cred_t *cr)
{
        return (cr->cr_grps == NULL ? &cr->cr_gid : cr->cr_grps->crg_groups);
}

int
crgetngroups(const cred_t *cr)
{
        return (cr->cr_grps == NULL ? 0 : cr->cr_grps->crg_ngroups);
}

void
cred2prcred(const cred_t *cr, prcred_t *pcrp)
{
        pcrp->pr_euid = cr->cr_uid;
        pcrp->pr_ruid = cr->cr_ruid;
        pcrp->pr_suid = cr->cr_suid;
        pcrp->pr_egid = cr->cr_gid;
        pcrp->pr_rgid = cr->cr_rgid;
        pcrp->pr_sgid = cr->cr_sgid;
        pcrp->pr_groups[0] = 0; /* in case ngroups == 0 */
        pcrp->pr_ngroups = cr->cr_grps == NULL ? 0 : cr->cr_grps->crg_ngroups;

        if (pcrp->pr_ngroups != 0)
                bcopy(cr->cr_grps->crg_groups, pcrp->pr_groups,
                    sizeof (gid_t) * pcrp->pr_ngroups);
}

static int
cred2ucaud(const cred_t *cr, auditinfo64_addr_t *ainfo, const cred_t *rcr)
{
        auditinfo_addr_t        *ai;
        au_tid_addr_t   tid;

        if (secpolicy_audit_getattr(rcr, B_TRUE) != 0)
                return (-1);

        ai = CR_AUINFO(cr);     /* caller makes sure this is non-NULL */
        tid = ai->ai_termid;

        ainfo->ai_auid = ai->ai_auid;
        ainfo->ai_mask = ai->ai_mask;
        ainfo->ai_asid = ai->ai_asid;

        ainfo->ai_termid.at_type = tid.at_type;
        bcopy(&tid.at_addr, &ainfo->ai_termid.at_addr, 4 * sizeof (uint_t));

        ainfo->ai_termid.at_port.at_major = (uint32_t)getmajor(tid.at_port);
        ainfo->ai_termid.at_port.at_minor = (uint32_t)getminor(tid.at_port);

        return (0);
}

void
cred2uclabel(const cred_t *cr, bslabel_t *labelp)
{
        ts_label_t      *tslp;

        if ((tslp = crgetlabel(cr)) != NULL)
                bcopy(&tslp->tsl_label, labelp, sizeof (bslabel_t));
}

/*
 * Convert a credential into a "ucred".  Allow the caller to specify
 * and aligned buffer, e.g., in an mblk, so we don't have to allocate
 * memory and copy it twice.
 *
 * This function may call cred2ucaud(), which calls CRED(). Since this
 * can be called from an interrupt thread, receiver's cred (rcr) is needed
 * to determine whether audit info should be included.
 */
struct ucred_s *
cred2ucred(const cred_t *cr, pid_t pid, void *buf, const cred_t *rcr)
{
        struct ucred_s *uc;
        uint32_t realsz = ucredminsize(cr);
        ts_label_t *tslp = is_system_labeled() ? crgetlabel(cr) : NULL;

        /* The structure isn't always completely filled in, so zero it */
        if (buf == NULL) {
                uc = kmem_zalloc(realsz, KM_SLEEP);
        } else {
                bzero(buf, realsz);
                uc = buf;
        }
        uc->uc_size = realsz;
        uc->uc_pid = pid;
        uc->uc_projid = cr->cr_projid;
        uc->uc_zoneid = crgetzoneid(cr);

        if (REMOTE_PEER_CRED(cr)) {
                /*
                 * Other than label, the rest of cred info about a
                 * remote peer isn't available. Copy the label directly
                 * after the header where we generally copy the prcred.
                 * That's why we use sizeof (struct ucred_s).  The other
                 * offset fields are initialized to 0.
                 */
                uc->uc_labeloff = tslp == NULL ? 0 : sizeof (struct ucred_s);
        } else {
                uc->uc_credoff = UCRED_CRED_OFF;
                uc->uc_privoff = UCRED_PRIV_OFF;
                uc->uc_audoff = UCRED_AUD_OFF;
                uc->uc_labeloff = tslp == NULL ? 0 : UCRED_LABEL_OFF;

                cred2prcred(cr, UCCRED(uc));
                cred2prpriv(cr, UCPRIV(uc));

                if (audoff == 0 || cred2ucaud(cr, UCAUD(uc), rcr) != 0)
                        uc->uc_audoff = 0;
        }
        if (tslp != NULL)
                bcopy(&tslp->tsl_label, UCLABEL(uc), sizeof (bslabel_t));

        return (uc);
}

/*
 * Don't allocate the non-needed group entries.  Note: this function
 * must match the code in cred2ucred; they must agree about the
 * minimal size of the ucred.
 */
uint32_t
ucredminsize(const cred_t *cr)
{
        int ndiff;

        if (cr == NULL)
                return (ucredsize);

        if (REMOTE_PEER_CRED(cr)) {
                if (is_system_labeled())
                        return (sizeof (struct ucred_s) + sizeof (bslabel_t));
                else
                        return (sizeof (struct ucred_s));
        }

        if (cr->cr_grps == NULL)
                ndiff = ngroups_max - 1;        /* Needs one for prcred_t */
        else
                ndiff = ngroups_max - cr->cr_grps->crg_ngroups;

        return (ucredsize - ndiff * sizeof (gid_t));
}

/*
 * Get the "ucred" of a process.
 */
struct ucred_s *
pgetucred(proc_t *p)
{
        cred_t *cr;
        struct ucred_s *uc;

        mutex_enter(&p->p_crlock);
        cr = p->p_cred;
        crhold(cr);
        mutex_exit(&p->p_crlock);

        uc = cred2ucred(cr, p->p_pid, NULL, CRED());
        crfree(cr);

        return (uc);
}

/*
 * If the reply status is NFSERR_EACCES, it may be because we are
 * root (no root net access).  Check the real uid, if it isn't root
 * make that the uid instead and retry the call.
 * Private interface for NFS.
 */
cred_t *
crnetadjust(cred_t *cr)
{
        if (cr->cr_uid == 0 && cr->cr_ruid != 0) {
                cr = crdup(cr);
                cr->cr_uid = cr->cr_ruid;
                return (cr);
        }
        return (NULL);
}

/*
 * The reference count is of interest when you want to check
 * whether it is ok to modify the credential in place.
 */
uint_t
crgetref(const cred_t *cr)
{
        return (cr->cr_ref);
}

static int
get_c2audit_load(void)
{
        static int      gotit = 0;
        static int      c2audit_load;

        if (gotit)
                return (c2audit_load);
        c2audit_load = 1;               /* set default value once */
        if (mod_sysctl(SYS_CHECK_EXCLUDE, "c2audit") != 0)
                c2audit_load = 0;
        gotit++;

        return (c2audit_load);
}

int
get_audit_ucrsize(void)
{
        return (get_c2audit_load() ? sizeof (auditinfo64_addr_t) : 0);
}

/*
 * Set zone pointer in credential to indicated value.  First adds a
 * hold for the new zone, then drops the hold on previous zone (if any).
 * This is done in this order in case the old and new zones are the
 * same.
 */
void
crsetzone(cred_t *cr, zone_t *zptr)
{
        zone_t *oldzptr = cr->cr_zone;

        ASSERT(cr != kcred);
        ASSERT(cr->cr_ref <= 2);
        cr->cr_zone = zptr;
        zone_cred_hold(zptr);
        if (oldzptr)
                zone_cred_rele(oldzptr);
}

/*
 * Create a new cred based on the supplied label
 */
cred_t *
newcred_from_bslabel(bslabel_t *blabel, uint32_t doi, int flags)
{
        ts_label_t *lbl = labelalloc(blabel, doi, flags);
        cred_t *cr = NULL;

        if (lbl != NULL) {
                if ((cr = crdup_flags(dummycr, flags)) != NULL) {
                        cr->cr_label = lbl;
                } else {
                        label_rele(lbl);
                }
        }

        return (cr);
}

/*
 * Derive a new cred from the existing cred, but with a different label.
 * To be used when a cred is being shared, but the label needs to be changed
 * by a caller without affecting other users
 */
cred_t *
copycred_from_tslabel(const cred_t *cr, ts_label_t *label, int flags)
{
        cred_t *newcr = NULL;

        if ((newcr = crdup_flags(cr, flags)) != NULL) {
                if (newcr->cr_label != NULL)
                        label_rele(newcr->cr_label);
                label_hold(label);
                newcr->cr_label = label;
        }

        return (newcr);
}

/*
 * Derive a new cred from the existing cred, but with a different label.
 */
cred_t *
copycred_from_bslabel(const cred_t *cr, bslabel_t *blabel,
    uint32_t doi, int flags)
{
        ts_label_t *lbl = labelalloc(blabel, doi, flags);
        cred_t  *newcr = NULL;

        if (lbl != NULL) {
                newcr = copycred_from_tslabel(cr, lbl, flags);
                label_rele(lbl);
        }

        return (newcr);
}

/*
 * This function returns a pointer to the kcred-equivalent in the current zone.
 */
cred_t *
zone_kcred(void)
{
        zone_t *zone;

        if ((zone = CRED()->cr_zone) != NULL)
                return (zone->zone_kcred);
        else
                return (kcred);
}

boolean_t
valid_ephemeral_uid(zone_t *zone, uid_t id)
{
        ephemeral_zsd_t *eph_zsd;
        if (id <= IDMAP_WK__MAX_UID)
                return (B_TRUE);

        eph_zsd = get_ephemeral_zsd(zone);
        ASSERT(eph_zsd != NULL);
        membar_consumer();
        return (id > eph_zsd->min_uid && id <= eph_zsd->last_uid);
}

boolean_t
valid_ephemeral_gid(zone_t *zone, gid_t id)
{
        ephemeral_zsd_t *eph_zsd;
        if (id <= IDMAP_WK__MAX_GID)
                return (B_TRUE);

        eph_zsd = get_ephemeral_zsd(zone);
        ASSERT(eph_zsd != NULL);
        membar_consumer();
        return (id > eph_zsd->min_gid && id <= eph_zsd->last_gid);
}

int
eph_uid_alloc(zone_t *zone, int flags, uid_t *start, int count)
{
        ephemeral_zsd_t *eph_zsd = get_ephemeral_zsd(zone);

        ASSERT(eph_zsd != NULL);

        mutex_enter(&eph_zsd->eph_lock);

        /* Test for unsigned integer wrap around */
        if (eph_zsd->last_uid + count < eph_zsd->last_uid) {
                mutex_exit(&eph_zsd->eph_lock);
                return (-1);
        }

        /* first call or idmap crashed and state corrupted */
        if (flags != 0)
                eph_zsd->min_uid = eph_zsd->last_uid;

        hasephids = B_TRUE;
        *start = eph_zsd->last_uid + 1;
        atomic_add_32(&eph_zsd->last_uid, count);
        mutex_exit(&eph_zsd->eph_lock);
        return (0);
}

int
eph_gid_alloc(zone_t *zone, int flags, gid_t *start, int count)
{
        ephemeral_zsd_t *eph_zsd = get_ephemeral_zsd(zone);

        ASSERT(eph_zsd != NULL);

        mutex_enter(&eph_zsd->eph_lock);

        /* Test for unsigned integer wrap around */
        if (eph_zsd->last_gid + count < eph_zsd->last_gid) {
                mutex_exit(&eph_zsd->eph_lock);
                return (-1);
        }

        /* first call or idmap crashed and state corrupted */
        if (flags != 0)
                eph_zsd->min_gid = eph_zsd->last_gid;

        hasephids = B_TRUE;
        *start = eph_zsd->last_gid + 1;
        atomic_add_32(&eph_zsd->last_gid, count);
        mutex_exit(&eph_zsd->eph_lock);
        return (0);
}

/*
 * IMPORTANT.The two functions get_ephemeral_data() and set_ephemeral_data()
 * are project private functions that are for use of the test system only and
 * are not to be used for other purposes.
 */

void
get_ephemeral_data(zone_t *zone, uid_t *min_uid, uid_t *last_uid,
    gid_t *min_gid, gid_t *last_gid)
{
        ephemeral_zsd_t *eph_zsd = get_ephemeral_zsd(zone);

        ASSERT(eph_zsd != NULL);

        mutex_enter(&eph_zsd->eph_lock);

        *min_uid = eph_zsd->min_uid;
        *last_uid = eph_zsd->last_uid;
        *min_gid = eph_zsd->min_gid;
        *last_gid = eph_zsd->last_gid;

        mutex_exit(&eph_zsd->eph_lock);
}


void
set_ephemeral_data(zone_t *zone, uid_t min_uid, uid_t last_uid,
    gid_t min_gid, gid_t last_gid)
{
        ephemeral_zsd_t *eph_zsd = get_ephemeral_zsd(zone);

        ASSERT(eph_zsd != NULL);

        mutex_enter(&eph_zsd->eph_lock);

        if (min_uid != 0)
                eph_zsd->min_uid = min_uid;
        if (last_uid != 0)
                eph_zsd->last_uid = last_uid;
        if (min_gid != 0)
                eph_zsd->min_gid = min_gid;
        if (last_gid != 0)
                eph_zsd->last_gid = last_gid;

        mutex_exit(&eph_zsd->eph_lock);
}

/*
 * If the credential user SID or group SID is mapped to an ephemeral
 * ID, map the credential to nobody.
 */
cred_t *
crgetmapped(const cred_t *cr)
{
        ephemeral_zsd_t *eph_zsd;
        /*
         * Someone incorrectly passed a NULL cred to a vnode operation
         * either on purpose or by calling CRED() in interrupt context.
         */
        if (cr == NULL)
                return (NULL);

        if (cr->cr_ksid != NULL) {
                if (cr->cr_ksid->kr_sidx[KSID_USER].ks_id > MAXUID) {
                        eph_zsd = get_ephemeral_zsd(crgetzone(cr));
                        return (eph_zsd->eph_nobody);
                }

                if (cr->cr_ksid->kr_sidx[KSID_GROUP].ks_id > MAXUID) {
                        eph_zsd = get_ephemeral_zsd(crgetzone(cr));
                        return (eph_zsd->eph_nobody);
                }
        }

        return ((cred_t *)cr);
}

/* index should be in range for a ksidindex_t */
void
crsetsid(cred_t *cr, ksid_t *ksp, int index)
{
        ASSERT(cr->cr_ref <= 2);
        ASSERT(index >= 0 && index < KSID_COUNT);
        if (cr->cr_ksid == NULL && ksp == NULL)
                return;
        cr->cr_ksid = kcrsid_setsid(cr->cr_ksid, ksp, index);
}

void
crsetsidlist(cred_t *cr, ksidlist_t *ksl)
{
        ASSERT(cr->cr_ref <= 2);
        if (cr->cr_ksid == NULL && ksl == NULL)
                return;
        cr->cr_ksid = kcrsid_setsidlist(cr->cr_ksid, ksl);
}

ksid_t *
crgetsid(const cred_t *cr, int i)
{
        ASSERT(i >= 0 && i < KSID_COUNT);
        if (cr->cr_ksid != NULL && cr->cr_ksid->kr_sidx[i].ks_domain)
                return ((ksid_t *)&cr->cr_ksid->kr_sidx[i]);
        return (NULL);
}

ksidlist_t *
crgetsidlist(const cred_t *cr)
{
        if (cr->cr_ksid != NULL)
                return (cr->cr_ksid->kr_sidlist);
        return (NULL);
}

/*
 * Interface to set the effective and permitted privileges for
 * a credential; this interface does no security checks and is
 * intended for kernel (file)servers creating credentials with
 * specific privileges.
 */
int
crsetpriv(cred_t *cr, ...)
{
        va_list ap;
        const char *privnm;

        ASSERT(cr->cr_ref <= 2);

        priv_set_PA(cr);

        va_start(ap, cr);

        while ((privnm = va_arg(ap, const char *)) != NULL) {
                int priv = priv_getbyname(privnm, 0);
                if (priv < 0)
                        return (-1);

                priv_addset(&CR_PPRIV(cr), priv);
                priv_addset(&CR_EPRIV(cr), priv);
        }
        priv_adjust_PA(cr);
        va_end(ap);
        return (0);
}

/*
 * Interface to effectively set the PRIV_ALL for
 * a credential; this interface does no security checks and is
 * intended for kernel (file)servers to extend the user credentials
 * to be ALL, like either kcred or zcred.
 */
void
crset_zone_privall(cred_t *cr)
{
        zone_t  *zone = crgetzone(cr);

        priv_fillset(&CR_LPRIV(cr));
        CR_EPRIV(cr) = CR_PPRIV(cr) = CR_IPRIV(cr) = CR_LPRIV(cr);
        priv_intersect(zone->zone_privset, &CR_LPRIV(cr));
        priv_intersect(zone->zone_privset, &CR_EPRIV(cr));
        priv_intersect(zone->zone_privset, &CR_IPRIV(cr));
        priv_intersect(zone->zone_privset, &CR_PPRIV(cr));
}

struct credklpd *
crgetcrklpd(const cred_t *cr)
{
        return (cr->cr_klpd);
}

void
crsetcrklpd(cred_t *cr, struct credklpd *crklpd)
{
        ASSERT(cr->cr_ref <= 2);

        if (cr->cr_klpd != NULL)
                crklpd_rele(cr->cr_klpd);
        cr->cr_klpd = crklpd;
}

credgrp_t *
crgrpcopyin(int n, gid_t *gidset)
{
        credgrp_t *mem;
        size_t sz = CREDGRPSZ(n);

        ASSERT(n > 0);

        mem = kmem_alloc(sz, KM_SLEEP);

        if (copyin(gidset, mem->crg_groups, sizeof (gid_t) * n)) {
                kmem_free(mem, sz);
                return (NULL);
        }
        mem->crg_ref = 1;
        mem->crg_ngroups = n;
        qsort(mem->crg_groups, n, sizeof (gid_t), gidcmp);
        return (mem);
}

const gid_t *
crgetggroups(const credgrp_t *grps)
{
        return (grps->crg_groups);
}

void
crsetcredgrp(cred_t *cr, credgrp_t *grps)
{
        ASSERT(cr->cr_ref <= 2);

        if (cr->cr_grps != NULL)
                crgrprele(cr->cr_grps);

        cr->cr_grps = grps;
}

void
crgrprele(credgrp_t *grps)
{
        if (atomic_dec_32_nv(&grps->crg_ref) == 0)
                kmem_free(grps, CREDGRPSZ(grps->crg_ngroups));
}

static void
crgrphold(credgrp_t *grps)
{
        atomic_inc_32(&grps->crg_ref);
}