1 files changed, 128 insertions, 0 deletions
diff --git a/lib/libc/posix1e/acl_calc_mask.c b/lib/libc/posix1e/acl_calc_mask.c
new file mode 100644
index 0000000..a2d1527
--- /dev/null
+++ b/lib/libc/posix1e/acl_calc_mask.c
@@ -0,0 +1,128 @@
+/*
+ * Copyright (c) 2001-2002 Chris D. Faulhaber
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include "namespace.h"
+#include <sys/acl.h>
+#include "un-namespace.h"
+
+#include <errno.h>
+#include <stdio.h>
+
+#include "acl_support.h"
+
+/*
+ * acl_calc_mask() (23.4.2): calculate and set the permissions
+ * associated with the ACL_MASK ACL entry.  If the ACL already
+ * contains an ACL_MASK entry, its permissions shall be
+ * overwritten; if not, one shall be added.
+ */
+int
+acl_calc_mask(acl_t *acl_p)
+{
+	struct acl	*acl_int, *acl_int_new;
+	acl_t		acl_new;
+	int		i, mask_mode, mask_num;
+
+	/*
+	 * (23.4.2.4) requires acl_p to point to a pointer to a valid ACL.
+	 * Since one of the primary reasons to use this function would be
+	 * to calculate the appropriate mask to obtain a valid ACL, we only
+	 * perform sanity checks here and validate the ACL prior to
+	 * returning.
+	 */
+	if (acl_p == NULL || *acl_p == NULL) {
+		errno = EINVAL;
+		return (-1);
+	}
+
+	if (!_acl_brand_may_be(*acl_p, ACL_BRAND_POSIX)) {
+		errno = EINVAL;
+		return (-1);
+	}
+	_acl_brand_as(*acl_p, ACL_BRAND_POSIX);
+
+	acl_int = &(*acl_p)->ats_acl;
+	if ((acl_int->acl_cnt < 3) || (acl_int->acl_cnt > ACL_MAX_ENTRIES)) {
+		errno = EINVAL;
+		return (-1);
+	}
+
+	acl_new = acl_dup(*acl_p);
+	if (acl_new == NULL)
+		return (-1);
+	acl_int_new = &acl_new->ats_acl;
+
+	mask_mode = 0;
+	mask_num = -1;
+
+	/* gather permissions and find a mask entry */
+	for (i = 0; i < acl_int_new->acl_cnt; i++) {
+		switch(acl_int_new->acl_entry[i].ae_tag) {
+		case ACL_USER:
+		case ACL_GROUP:
+		case ACL_GROUP_OBJ:
+			mask_mode |=
+			    acl_int_new->acl_entry[i].ae_perm & ACL_PERM_BITS;
+			break;
+		case ACL_MASK:
+			mask_num = i;
+			break;
+		}
+	}
+
+	/* if a mask entry already exists, overwrite the perms */
+	if (mask_num != -1)
+		acl_int_new->acl_entry[mask_num].ae_perm = mask_mode;
+	else {
+		/* if no mask exists, check acl_cnt... */
+		if (acl_int_new->acl_cnt == ACL_MAX_ENTRIES) {
+			errno = ENOMEM;
+			return (-1);
+		}
+		/* ...and add the mask entry */
+		acl_int_new->acl_entry[acl_int_new->acl_cnt].ae_tag = ACL_MASK;
+		acl_int_new->acl_entry[acl_int_new->acl_cnt].ae_id =
+		    ACL_UNDEFINED_ID;
+		acl_int_new->acl_entry[acl_int_new->acl_cnt].ae_perm =
+		    mask_mode;
+		acl_int_new->acl_cnt++;
+	}
+
+	if (acl_valid(acl_new) == -1) {
+		errno = EINVAL;
+		acl_free(acl_new);
+		return (-1);
+	}
+
+	**acl_p = *acl_new;
+	acl_free(acl_new);
+
+	return (0);
+}