1 files changed, 102 insertions, 0 deletions
diff --git a/lib/isc/fsaccess.c b/lib/isc/fsaccess.c
new file mode 100644
index 0000000..5c97183
--- /dev/null
+++ b/lib/isc/fsaccess.c
@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) 2004, 2005, 2007  Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) 2000, 2001  Internet Software Consortium.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+ * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* $Id: fsaccess.c,v 1.10 2007/06/19 23:47:17 tbox Exp $ */
+
+/*! \file
+ * \brief
+ * This file contains the OS-independent functionality of the API.
+ */
+#include <isc/fsaccess.h>
+#include <isc/result.h>
+#include <isc/util.h>
+
+/*!
+ * Shorthand.  Maybe ISC__FSACCESS_PERMISSIONBITS should not even be in
+ * <isc/fsaccess.h>.  Could check consistency with sizeof(isc_fsaccess_t)
+ * and the number of bits in each function.
+ */
+#define STEP		(ISC__FSACCESS_PERMISSIONBITS)
+#define GROUP		(STEP)
+#define OTHER		(STEP * 2)
+
+void
+isc_fsaccess_add(int trustee, int permission, isc_fsaccess_t *access) {
+	REQUIRE(trustee <= 0x7);
+	REQUIRE(permission <= 0xFF);
+
+	if ((trustee & ISC_FSACCESS_OWNER) != 0)
+		*access |= permission;
+
+	if ((trustee & ISC_FSACCESS_GROUP) != 0)
+		*access |= (permission << GROUP);
+
+	if ((trustee & ISC_FSACCESS_OTHER) != 0)
+		*access |= (permission << OTHER);
+}
+
+void
+isc_fsaccess_remove(int trustee, int permission, isc_fsaccess_t *access) {
+	REQUIRE(trustee <= 0x7);
+	REQUIRE(permission <= 0xFF);
+
+
+	if ((trustee & ISC_FSACCESS_OWNER) != 0)
+		*access &= ~permission;
+
+	if ((trustee & ISC_FSACCESS_GROUP) != 0)
+		*access &= ~(permission << GROUP);
+
+	if ((trustee & ISC_FSACCESS_OTHER) != 0)
+		*access &= ~(permission << OTHER);
+}
+
+static isc_result_t
+check_bad_bits(isc_fsaccess_t access, isc_boolean_t is_dir) {
+	isc_fsaccess_t bits;
+
+	/*
+	 * Check for disallowed user bits.
+	 */
+	if (is_dir)
+		bits = ISC_FSACCESS_READ |
+		       ISC_FSACCESS_WRITE |
+		       ISC_FSACCESS_EXECUTE;
+	else
+		bits = ISC_FSACCESS_CREATECHILD |
+		       ISC_FSACCESS_ACCESSCHILD |
+		       ISC_FSACCESS_DELETECHILD |
+		       ISC_FSACCESS_LISTDIRECTORY;
+
+	/*
+	 * Set group bad bits.
+	 */
+	bits |= bits << STEP;
+	/*
+	 * Set other bad bits.
+	 */
+	bits |= bits << STEP;
+
+	if ((access & bits) != 0) {
+		if (is_dir)
+			return (ISC_R_NOTFILE);
+		else
+			return (ISC_R_NOTDIRECTORY);
+	}
+
+	return (ISC_R_SUCCESS);
+}