lib/uuid.c: introduce a few more generic helpers
There are new helpers in this patch:
uuid_is_valid checks if a UUID is valid
uuid_be_to_bin converts from string to binary (big endian)
uuid_le_to_bin converts from string to binary (little endian)
They will be used in future, i.e. in the following patches in the series.
This also moves the indices arrays to lib/uuid.c to be shared accross
modules.
[andriy.shevchenko@linux.intel.com: fix typo]
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/uuid.c b/lib/uuid.c
index 6c81c0b..82787f6 100644
--- a/lib/uuid.c
+++ b/lib/uuid.c
@@ -19,10 +19,17 @@
*/
#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 u8 uuid_le_index[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
+EXPORT_SYMBOL(uuid_le_index);
+const u8 uuid_be_index[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
+EXPORT_SYMBOL(uuid_be_index);
+
/***************************************************************
* Random UUID interface
*
@@ -65,3 +72,61 @@
bu->b[6] = (bu->b[6] & 0x0F) | 0x40;
}
EXPORT_SYMBOL_GPL(uuid_be_gen);
+
+/**
+ * uuid_is_valid - checks if UUID string 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_to_bin(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 uuid_le_to_bin(const char *uuid, uuid_le *u)
+{
+ return __uuid_to_bin(uuid, u->b, uuid_le_index);
+}
+EXPORT_SYMBOL(uuid_le_to_bin);
+
+int uuid_be_to_bin(const char *uuid, uuid_be *u)
+{
+ return __uuid_to_bin(uuid, u->b, uuid_be_index);
+}
+EXPORT_SYMBOL(uuid_be_to_bin);