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-rw-r--r--lib/uuid.c133
1 files changed, 133 insertions, 0 deletions
diff --git a/lib/uuid.c b/lib/uuid.c
new file mode 100644
index 0000000000..e309b4c5be
--- /dev/null
+++ b/lib/uuid.c
@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Unified UUID/GUID definition
+ *
+ * Copyright (C) 2009, 2016 Intel Corp.
+ * Huang Ying <ying.huang@intel.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/uuid.h>
+#include <linux/random.h>
+
+const guid_t guid_null;
+EXPORT_SYMBOL(guid_null);
+const uuid_t uuid_null;
+EXPORT_SYMBOL(uuid_null);
+
+const u8 guid_index[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
+const u8 uuid_index[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
+
+/**
+ * generate_random_uuid - generate a random UUID
+ * @uuid: where to put the generated UUID
+ *
+ * Random UUID interface
+ *
+ * Used to create a Boot ID or a filesystem UUID/GUID, but can be
+ * useful for other kernel drivers.
+ */
+void generate_random_uuid(unsigned char uuid[16])
+{
+ get_random_bytes(uuid, 16);
+ /* Set UUID version to 4 --- truly random generation */
+ uuid[6] = (uuid[6] & 0x0F) | 0x40;
+ /* Set the UUID variant to DCE */
+ uuid[8] = (uuid[8] & 0x3F) | 0x80;
+}
+EXPORT_SYMBOL(generate_random_uuid);
+
+void generate_random_guid(unsigned char guid[16])
+{
+ get_random_bytes(guid, 16);
+ /* Set GUID version to 4 --- truly random generation */
+ guid[7] = (guid[7] & 0x0F) | 0x40;
+ /* Set the GUID variant to DCE */
+ guid[8] = (guid[8] & 0x3F) | 0x80;
+}
+EXPORT_SYMBOL(generate_random_guid);
+
+static void __uuid_gen_common(__u8 b[16])
+{
+ get_random_bytes(b, 16);
+ /* reversion 0b10 */
+ b[8] = (b[8] & 0x3F) | 0x80;
+}
+
+void guid_gen(guid_t *lu)
+{
+ __uuid_gen_common(lu->b);
+ /* version 4 : random generation */
+ lu->b[7] = (lu->b[7] & 0x0F) | 0x40;
+}
+EXPORT_SYMBOL_GPL(guid_gen);
+
+void uuid_gen(uuid_t *bu)
+{
+ __uuid_gen_common(bu->b);
+ /* version 4 : random generation */
+ bu->b[6] = (bu->b[6] & 0x0F) | 0x40;
+}
+EXPORT_SYMBOL_GPL(uuid_gen);
+
+/**
+ * uuid_is_valid - checks if a UUID string is valid
+ * @uuid: UUID string to check
+ *
+ * Description:
+ * It checks if the UUID string is following the format:
+ * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
+ *
+ * where x is a hex digit.
+ *
+ * Return: true if input is valid UUID string.
+ */
+bool uuid_is_valid(const char *uuid)
+{
+ unsigned int i;
+
+ for (i = 0; i < UUID_STRING_LEN; i++) {
+ if (i == 8 || i == 13 || i == 18 || i == 23) {
+ if (uuid[i] != '-')
+ return false;
+ } else if (!isxdigit(uuid[i])) {
+ return false;
+ }
+ }
+
+ return true;
+}
+EXPORT_SYMBOL(uuid_is_valid);
+
+static int __uuid_parse(const char *uuid, __u8 b[16], const u8 ei[16])
+{
+ static const u8 si[16] = {0,2,4,6,9,11,14,16,19,21,24,26,28,30,32,34};
+ unsigned int i;
+
+ if (!uuid_is_valid(uuid))
+ return -EINVAL;
+
+ for (i = 0; i < 16; i++) {
+ int hi = hex_to_bin(uuid[si[i] + 0]);
+ int lo = hex_to_bin(uuid[si[i] + 1]);
+
+ b[ei[i]] = (hi << 4) | lo;
+ }
+
+ return 0;
+}
+
+int guid_parse(const char *uuid, guid_t *u)
+{
+ return __uuid_parse(uuid, u->b, guid_index);
+}
+EXPORT_SYMBOL(guid_parse);
+
+int uuid_parse(const char *uuid, uuid_t *u)
+{
+ return __uuid_parse(uuid, u->b, uuid_index);
+}
+EXPORT_SYMBOL(uuid_parse);