libspl: move cred implementation from libzpool

Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes #17861

lib/libspl/Makefile.am

@@ -17,6 +17,7 @@ libspl_la_SOURCES = \
 	%D%/libspl_impl.h \
 	%D%/atomic.c \
 	%D%/condvar.c \
+	%D%/cred.c \
 	%D%/getexecname.c \
 	%D%/list.c \
 	%D%/mkdirp.c \

lib/libspl/cred.c

@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: CDDL-1.0
+/*
+ * 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 https://opensource.org/licenses/CDDL-1.0.
+ * 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) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2018 by Delphix. All rights reserved.
+ * Copyright (c) 2016 Actifio, Inc. All rights reserved.
+ * Copyright (c) 2025, Klara, Inc.
+ */
+
+#include <sys/cred.h>
+
+uid_t
+crgetuid(cred_t *cr)
+{
+	(void) cr;
+	return (0);
+}
+
+uid_t
+crgetruid(cred_t *cr)
+{
+	(void) cr;
+	return (0);
+}
+
+gid_t
+crgetgid(cred_t *cr)
+{
+	(void) cr;
+	return (0);
+}
+
+int
+crgetngroups(cred_t *cr)
+{
+	(void) cr;
+	return (0);
+}
+
+gid_t *
+crgetgroups(cred_t *cr)
+{
+	(void) cr;
+	return (NULL);
+}
+

lib/libzpool/kernel.c

@@ -635,41 +635,6 @@ kernel_fini(void)
 	random_fini();
 }
 
-uid_t
-crgetuid(cred_t *cr)
-{
-	(void) cr;
-	return (0);
-}
-
-uid_t
-crgetruid(cred_t *cr)
-{
-	(void) cr;
-	return (0);
-}
-
-gid_t
-crgetgid(cred_t *cr)
-{
-	(void) cr;
-	return (0);
-}
-
-int
-crgetngroups(cred_t *cr)
-{
-	(void) cr;
-	return (0);
-}
-
-gid_t *
-crgetgroups(cred_t *cr)
-{
-	(void) cr;
-	return (NULL);
-}
-
 int
 zfs_secpolicy_snapshot_perms(const char *name, cred_t *cr)
 {