blob: 769209b901d182ff5a0f06d36d170db03de99bdb [file] [log] [blame]
Patrick Williams8dd68482022-10-04 07:57:18 -05001From af17d357674393565c8be15f21c86cba972963e7 Mon Sep 17 00:00:00 2001
2From: Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com>
3Date: Thu, 4 Aug 2022 16:46:47 +0100
4Subject: [PATCH 08/26] lib: uuid: introduce be_uuid_str_to_le_bin function
5
6convert big endian UUID string to little endian buffer
7
8Signed-off-by: Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com>
9Upstream-Status: Submitted [cover letter: https://lore.kernel.org/all/20220926101723.9965-1-abdellatif.elkhlifi@arm.com/]
10---
11
12Changelog:
13===============
14
15v4:
16
17* rename ffa_uuid_str_to_bin to be_uuid_str_to_le_bin and put in
18 a standalone commit (the current)
19
20v3:
21
22* introduce ffa_uuid_str_to_bin (provided by
23 arm_ffa: introduce Arm FF-A low-level driver)
24
25 include/uuid.h | 6 +++++
26 lib/uuid.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++
27 2 files changed, 69 insertions(+)
28
29diff --git a/include/uuid.h b/include/uuid.h
30index 4a4883d3b5..5355230b5e 100644
31--- a/include/uuid.h
32+++ b/include/uuid.h
33@@ -44,4 +44,10 @@ int uuid_guid_get_bin(const char *guid_str, unsigned char *guid_bin);
34 const char *uuid_guid_get_str(const unsigned char *guid_bin);
35 void gen_rand_uuid(unsigned char *uuid_bin);
36 void gen_rand_uuid_str(char *uuid_str, int str_format);
37+
38+/**
39+ * be_uuid_str_to_le_bin - Converts a big endian UUID string to a little endian buffer
40+ */
41+int be_uuid_str_to_le_bin(const char *uuid_str, unsigned char *uuid_bin);
42+
43 #endif
44diff --git a/lib/uuid.c b/lib/uuid.c
45index 284f8113ff..d0fa51d0bf 100644
46--- a/lib/uuid.c
47+++ b/lib/uuid.c
48@@ -1,6 +1,7 @@
49 // SPDX-License-Identifier: GPL-2.0+
50 /*
51 * Copyright 2011 Calxeda, Inc.
52+ * Copyright 2022 ARM Limited
53 */
54
55 #include <common.h>
56@@ -342,6 +343,68 @@ int uuid_str_to_bin(const char *uuid_str, unsigned char *uuid_bin,
57 return 0;
58 }
59
60+/**
61+ * be_uuid_str_to_le_bin - Converts a big endian UUID string to a little endian buffer
62+ * @uuid_str: UUID string in big endian format (36 bytes wide + '/0')
63+ * @uuid_bin: preallocated 16 bytes UUID buffer in little endian format
64+ *
65+ * UUID string is 36 characters (36 bytes):
66+ *
67+ * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
68+ * be be be be be
69+ *
70+ * where x is a hexadecimal character. Fields are separated by '-'s.
71+ * When converting to a binary UUID, these endianness rules apply:
72+ * be: means the field in the string is considered a big endian hex number
73+ * and should be converted to little endian binary format
74+ *
75+ * Return:
76+ *
77+ * uuid_bin filled with little endian UUID data
78+ * On success 0 is returned. Otherwise, failure code.
79+ */
80+int be_uuid_str_to_le_bin(const char *uuid_str, unsigned char *uuid_bin)
81+{
82+ u16 tmp16 = 0;
83+ u32 tmp32 = 0;
84+ u64 tmp64 = 0;
85+
86+ if (!uuid_str_valid(uuid_str) || !uuid_bin)
87+ return -EINVAL;
88+
89+ /*
90+ * reverse bytes from big to little endian
91+ */
92+ tmp32 = simple_strtoul(uuid_str, NULL, 16);
93+ memcpy(uuid_bin, &tmp32, 4);
94+
95+ /*
96+ * reverse bytes from big to little endian
97+ */
98+ tmp16 = simple_strtoul(uuid_str + 9, NULL, 16);
99+ memcpy(uuid_bin + 4, &tmp16, 2);
100+
101+ /*
102+ * reverse bytes from big to little endian
103+ */
104+ tmp16 = simple_strtoul(uuid_str + 14, NULL, 16);
105+ memcpy(uuid_bin + 6, &tmp16, 2);
106+
107+ /*
108+ * reverse bytes from big to little endian
109+ */
110+ tmp16 = simple_strtoul(uuid_str + 19, NULL, 16);
111+ memcpy(uuid_bin + 8, &tmp16, 2);
112+
113+ /*
114+ * reverse bytes from big to little endian
115+ */
116+ tmp64 = simple_strtoull(uuid_str + 24, NULL, 16);
117+ memcpy(uuid_bin + 10, (char *)&tmp64, 6);
118+
119+ return 0;
120+}
121+
122 /*
123 * uuid_bin_to_str() - convert big endian binary data to string UUID or GUID.
124 *
125--
1262.17.1
127