crypto: ccp - Add a sample library for ioctl use

Add a small shared library that demonstrates the usage of the
IOCTL interface.  This library can be linked to but, is
intended to be loaded and used by higher level languages
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

tools/crypto/ccp/Makefile

+# SPDX-License-Identifier: GPL-2.0-only
+CFLAGS += -D__EXPORTED_HEADERS__ -I../../../include/uapi -I../../../include
+
+TARGET = dbc_library.so
+
+all: $(TARGET)
+
+dbc_library.so: dbc.c
+	$(CC) $(CFLAGS) $(LDFLAGS) -shared -o $@ $<
+	chmod -x $@
+
+clean:
+	$(RM) $(TARGET)

tools/crypto/ccp/dbc.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AMD Secure Processor Dynamic Boost Control sample library
+ *
+ * Copyright (C) 2023 Advanced Micro Devices, Inc.
+ *
+ * Author: Mario Limonciello <mario.limonciello@amd.com>
+ */
+
+#include <assert.h>
+#include <string.h>
+#include <sys/ioctl.h>
+
+/* if uapi header isn't installed, this might not yet exist */
+#ifndef __packed
+#define __packed __attribute__((packed))
+#endif
+#include <linux/psp-dbc.h>
+
+int get_nonce(int fd, void *nonce_out, void *signature)
+{
+	struct dbc_user_nonce tmp = {
+		.auth_needed = !!signature,
+	};
+	int ret;
+
+	assert(nonce_out);
+
+	if (signature)
+		memcpy(tmp.signature, signature, sizeof(tmp.signature));
+
+	ret = ioctl(fd, DBCIOCNONCE, &tmp);
+	if (ret)
+		return ret;
+	memcpy(nonce_out, tmp.nonce, sizeof(tmp.nonce));
+
+	return 0;
+}
+
+int set_uid(int fd, __u8 *uid, __u8 *signature)
+{
+	struct dbc_user_setuid tmp;
+
+	assert(uid);
+	assert(signature);
+
+	memcpy(tmp.uid, uid, sizeof(tmp.uid));
+	memcpy(tmp.signature, signature, sizeof(tmp.signature));
+
+	return ioctl(fd, DBCIOCUID, &tmp);
+}
+
+int process_param(int fd, int msg_index, __u8 *signature, int *data)
+{
+	struct dbc_user_param tmp = {
+		.msg_index = msg_index,
+		.param = *data,
+	};
+	int ret;
+
+	assert(signature);
+	assert(data);
+
+	memcpy(tmp.signature, signature, sizeof(tmp.signature));
+
+	ret = ioctl(fd, DBCIOCPARAM, &tmp);
+	if (ret)
+		return ret;
+
+	*data = tmp.param;
+	return 0;
+}