common/acl/acl_common.c

	acl_common.c revision fa9e4066f08beec538e775443c5be79dd423fcab
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <sys/types.h>
#include <sys/acl.h>
#include <sys/stat.h>
#if defined(_KERNEL)
#include <sys/systm.h>
#else
#include <errno.h>
#include <stdlib.h>
#include <strings.h>
#include <assert.h>
#define ASSERT  assert
#endif


ace_t trivial_acl[] = {
    {-1, 0, ACE_OWNER, ACE_ACCESS_DENIED_ACE_TYPE},
    {-1, ACE_WRITE_ACL|ACE_WRITE_OWNER|ACE_WRITE_ATTRIBUTES|
        ACE_WRITE_NAMED_ATTRS, ACE_OWNER, ACE_ACCESS_ALLOWED_ACE_TYPE},
    {-1, 0, ACE_GROUP|ACE_IDENTIFIER_GROUP, ACE_ACCESS_DENIED_ACE_TYPE},
    {-1, 0, ACE_GROUP|ACE_IDENTIFIER_GROUP, ACE_ACCESS_ALLOWED_ACE_TYPE},
    {-1, ACE_WRITE_ACL|ACE_WRITE_OWNER| ACE_WRITE_ATTRIBUTES|
        ACE_WRITE_NAMED_ATTRS, ACE_EVERYONE, ACE_ACCESS_DENIED_ACE_TYPE},
    {-1, ACE_READ_ACL|ACE_READ_ATTRIBUTES|ACE_READ_NAMED_ATTRS|
        ACE_SYNCHRONIZE, ACE_EVERYONE, ACE_ACCESS_ALLOWED_ACE_TYPE}
};


void
adjust_ace_pair(ace_t *pair, mode_t mode)
{
    if (mode & S_IROTH)
        pair[1].a_access_mask |= ACE_READ_DATA;
    else
        pair[0].a_access_mask |= ACE_READ_DATA;
    if (mode & S_IWOTH)
        pair[1].a_access_mask |=
            ACE_WRITE_DATA|ACE_APPEND_DATA;
    else
        pair[0].a_access_mask |=
            ACE_WRITE_DATA|ACE_APPEND_DATA;
    if (mode & S_IXOTH)
        pair[1].a_access_mask |= ACE_EXECUTE;
    else
        pair[0].a_access_mask |= ACE_EXECUTE;
}

/*
 * ace_trivial:
 * determine whether an ace_t acl is trivial
 *
 * Trivialness implys that the acl is composed of only
 * owner, group, everyone entries.  ACL can't
 * have read_acl denied, and write_owner/write_acl/write_attributes
 * can only be owner@ entry.
 */
int
ace_trivial(ace_t *acep, int aclcnt)
{
    int i;
    int owner_seen = 0;
    int group_seen = 0;
    int everyone_seen = 0;

    for (i = 0; i != aclcnt; i++) {
        switch (acep[i].a_flags & 0xf040) {
        case ACE_OWNER:
            if (group_seen || everyone_seen)
                return (1);
            owner_seen++;
            break;
        case ACE_GROUP|ACE_IDENTIFIER_GROUP:
            if (everyone_seen || owner_seen == 0)
                return (1);
            group_seen++;
            break;

        case ACE_EVERYONE:
            if (owner_seen == 0 || group_seen == 0)
                return (1);
            everyone_seen++;
            break;
        default:
            return (1);

        }

        if (acep[i].a_flags & (ACE_FILE_INHERIT_ACE|
            ACE_DIRECTORY_INHERIT_ACE|ACE_NO_PROPAGATE_INHERIT_ACE|
            ACE_INHERIT_ONLY_ACE))
            return (1);

        /*
         * Special check for some special bits
         *
         * Don't allow anybody to deny reading an ACL
         */
        if ((acep[i].a_access_mask & ACE_READ_ACL) &&
            (acep[i].a_type == ACE_ACCESS_DENIED_ACE_TYPE))
            return (1);

        /*
         * Allow on owner@ to allow
         * write_acl/write_owner/write_attributes
         */
        if (acep[i].a_type == ACE_ACCESS_ALLOWED_ACE_TYPE &&
            (!(acep[i].a_flags & ACE_OWNER) && (acep[i].a_access_mask &
            (ACE_WRITE_OWNER|ACE_WRITE_ACL|ACE_WRITE_ATTRIBUTES))))
            return (1);
    }

    if ((owner_seen == 0) || (group_seen == 0) || (everyone_seen == 0))
        return (1);

    return (0);
}


/*
 * Generic shellsort, from K&R (1st ed, p 58.), somewhat modified.
 * v = Ptr to array/vector of objs
 * n = # objs in the array
 * s = size of each obj (must be multiples of a word size)
 * f = ptr to function to compare two objs
 *  returns (-1 = less than, 0 = equal, 1 = greater than
 */
void
ksort(caddr_t v, int n, int s, int (*f)())
{
    int g, i, j, ii;
    unsigned int *p1, *p2;
    unsigned int tmp;

    /* No work to do */
    if (v == NULL || n <= 1)
        return;

    /* Sanity check on arguments */
    ASSERT(((uintptr_t)v & 0x3) == 0 && (s & 0x3) == 0);
    ASSERT(s > 0);
    for (g = n / 2; g > 0; g /= 2) {
        for (i = g; i < n; i++) {
            for (j = i - g; j >= 0 &&
                (*f)(v + j * s, v + (j + g) * s) == 1;
                    j -= g) {
                p1 = (void *)(v + j * s);
                p2 = (void *)(v + (j + g) * s);
                for (ii = 0; ii < s / 4; ii++) {
                    tmp = *p1;
                    *p1++ = *p2;
                    *p2++ = tmp;
                }
            }
        }
    }
}

/*
 * Compare two acls, all fields.  Returns:
 * -1 (less than)
 *  0 (equal)
 * +1 (greater than)
 */
int
cmp2acls(void *a, void *b)
{
    aclent_t *x = (aclent_t *)a;
    aclent_t *y = (aclent_t *)b;

    /* Compare types */
    if (x->a_type < y->a_type)
        return (-1);
    if (x->a_type > y->a_type)
        return (1);
    /* Equal types; compare id's */
    if (x->a_id < y->a_id)
        return (-1);
    if (x->a_id > y->a_id)
        return (1);
    /* Equal ids; compare perms */
    if (x->a_perm < y->a_perm)
        return (-1);
    if (x->a_perm > y->a_perm)
        return (1);
    /* Totally equal */
    return (0);
}