libposix1e provides userland library calls for the POSIX.1e security

interface.  This commit introduces the library, as well as a modest
subset of the ACL calls, with some modifications to support multiple
ACL semantics.

Reviewed by:	eivind

1 files changed, 74 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..30ea02e
--- /dev/null
+++ b/lib/libc/posix1e/acl_calc_mask.c
@@ -0,0 +1,74 @@
+/*-
+ * Copyright (c) 1999 Robert N. M. Watson
+ * 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 THE 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.
+ *
+ *	$FreeBSD$
+ */
+/*
+ * acl_calc_mask(): POSIX.1e routine to recalculate the mask value
+ */
+
+#include <sys/types.h>
+#include <sys/acl.h>
+#include <sys/errno.h>
+#include <string.h>
+
+#include "acl_support.h"
+
+/*
+ * POSIX.1e ACL semantics:
+ *
+ * acl_calc_mask(): calculate an ACL_MASK entry for the ACL, then either
+ * insert into the ACL if there is none already, or replace the existing
+ * one.
+ */
+int
+acl_calc_mask(acl_t *acl_p)
+{
+	acl_perm_t	perm_union = ACL_PERM_NONE;
+	acl_t	acl = *acl_p;
+	int	mask_entry = -1;
+	int	i;
+
+	if (!acl_posix1e(acl))
+		return (0);
+	
+	/* search for ACL_MASK */
+	for (i = 0; i < acl->acl_cnt; i++)
+		if (acl->acl_entry[i].ae_tag == ACL_MASK)
+			mask_entry = i;
+		else
+			perm_union |= acl->acl_entry[i].ae_perm;
+
+	if (mask_entry != -1) {
+		/* already have a mask, replace */
+		acl->acl_entry[mask_entry].ae_perm = perm_union;
+	} else {
+		/* must add a new mask */
+		if (acl_add_entry(acl, ACL_MASK, 0, perm_union) == -1)
+			return (-1);
+	}
+
+	return (0);
+}