From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Subject: 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@xxxxxxxxxxxxxxx: fix typo]
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Reviewed-by: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
Cc: Dmitry Kasatkin <dmitry.kasatkin@xxxxxxxxx>
Cc: Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx>
Cc: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: "Theodore Ts'o" <tytso@xxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/uuid.h | 13 ++++++++
lib/uuid.c | 65 +++++++++++++++++++++++++++++++++++++++++
lib/vsprintf.c | 9 ++---
3 files changed, 82 insertions(+), 5 deletions(-)
diff -puN include/linux/uuid.h~lib-uuid-introduce-few-more-generic-helpers-for-uuid include/linux/uuid.h
--- a/include/linux/uuid.h~lib-uuid-introduce-few-more-generic-helpers-for-uuid
+++ a/include/linux/uuid.h
@@ -22,6 +22,11 @@
#include <uapi/linux/uuid.h>
+/*
+ * The length of a UUID string ("aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee")
+ * not including trailing NUL.
+ */
+#define UUID_STRING_LEN 36
static inline int uuid_le_cmp(const uuid_le u1, const uuid_le u2)
{
@@ -38,4 +43,12 @@ void generate_random_uuid(unsigned char
extern void uuid_le_gen(uuid_le *u);
extern void uuid_be_gen(uuid_be *u);
+bool __must_check uuid_is_valid(const char *uuid);
+
+extern const u8 uuid_le_index[16];
+extern const u8 uuid_be_index[16];
+
+int uuid_le_to_bin(const char *uuid, uuid_le *u);
+int uuid_be_to_bin(const char *uuid, uuid_be *u);
+
#endif
diff -puN lib/uuid.c~lib-uuid-introduce-few-more-generic-helpers-for-uuid lib/uuid.c
--- a/lib/uuid.c~lib-uuid-introduce-few-more-generic-helpers-for-uuid
+++ a/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 @@ void uuid_be_gen(uuid_be *bu)
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);
diff -puN lib/vsprintf.c~lib-uuid-introduce-few-more-generic-helpers-for-uuid lib/vsprintf.c
--- a/lib/vsprintf.c~lib-uuid-introduce-few-more-generic-helpers-for-uuid
+++ a/lib/vsprintf.c
@@ -30,6 +30,7 @@
#include <linux/ioport.h>
#include <linux/dcache.h>
#include <linux/cred.h>
+#include <linux/uuid.h>
#include <net/addrconf.h>
#ifdef CONFIG_BLOCK
#include <linux/blkdev.h>
@@ -1304,19 +1305,17 @@ static noinline_for_stack
char *uuid_string(char *buf, char *end, const u8 *addr,
struct printf_spec spec, const char *fmt)
{
- char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
+ char uuid[UUID_STRING_LEN + 1];
char *p = uuid;
int i;
- static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
- static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
- const u8 *index = be;
+ const u8 *index = uuid_be_index;
bool uc = false;
switch (*(++fmt)) {
case 'L':
uc = true; /* fall-through */
case 'l':
- index = le;
+ index = uuid_le_index;
break;
case 'B':
uc = true;
_
--
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