1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: utuuid -- UUID support functions
5  *
6  * Copyright (C) 2000 - 2023, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 
13 #define _COMPONENT          ACPI_COMPILER
14 ACPI_MODULE_NAME("utuuid")
15 
16 #if (defined ACPI_ASL_COMPILER || defined ACPI_EXEC_APP || defined ACPI_HELP_APP)
17 /*
18  * UUID support functions.
19  *
20  * This table is used to convert an input UUID ascii string to a 16 byte
21  * buffer and the reverse. The table maps a UUID buffer index 0-15 to
22  * the index within the 36-byte UUID string where the associated 2-byte
23  * hex value can be found.
24  *
25  * 36-byte UUID strings are of the form:
26  *     aabbccdd-eeff-gghh-iijj-kkllmmnnoopp
27  * Where aa-pp are one byte hex numbers, made up of two hex digits
28  *
29  * Note: This table is basically the inverse of the string-to-offset table
30  * found in the ACPI spec in the description of the to_UUID macro.
31  */
32 const u8 acpi_gbl_map_to_uuid_offset[UUID_BUFFER_LENGTH] = {
33 	6, 4, 2, 0, 11, 9, 16, 14, 19, 21, 24, 26, 28, 30, 32, 34
34 };
35 
36 /*******************************************************************************
37  *
38  * FUNCTION:    acpi_ut_convert_string_to_uuid
39  *
40  * PARAMETERS:  in_string           - 36-byte formatted UUID string
41  *              uuid_buffer         - Where the 16-byte UUID buffer is returned
42  *
43  * RETURN:      None. Output data is returned in the uuid_buffer
44  *
45  * DESCRIPTION: Convert a 36-byte formatted UUID string to 16-byte UUID buffer
46  *
47  ******************************************************************************/
48 
acpi_ut_convert_string_to_uuid(char * in_string,u8 * uuid_buffer)49 void acpi_ut_convert_string_to_uuid(char *in_string, u8 *uuid_buffer)
50 {
51 	u32 i;
52 
53 	for (i = 0; i < UUID_BUFFER_LENGTH; i++) {
54 		uuid_buffer[i] =
55 		    (acpi_ut_ascii_char_to_hex
56 		     (in_string[acpi_gbl_map_to_uuid_offset[i]]) << 4);
57 
58 		uuid_buffer[i] |=
59 		    acpi_ut_ascii_char_to_hex(in_string
60 					      [acpi_gbl_map_to_uuid_offset[i] +
61 					       1]);
62 	}
63 }
64 
65 /*******************************************************************************
66  *
67  * FUNCTION:    acpi_ut_convert_uuid_to_string
68  *
69  * PARAMETERS:  uuid_buffer         - 16-byte UUID buffer
70  *              out_string          - 36-byte formatted UUID string
71  *
72  * RETURN:      Status
73  *
74  * DESCRIPTION: Convert 16-byte UUID buffer to 36-byte formatted UUID string
75  *              out_string must be 37 bytes to include null terminator.
76  *
77  ******************************************************************************/
78 
acpi_ut_convert_uuid_to_string(char * uuid_buffer,char * out_string)79 acpi_status acpi_ut_convert_uuid_to_string(char *uuid_buffer, char *out_string)
80 {
81 	u32 i;
82 
83 	if (!uuid_buffer || !out_string) {
84 		return (AE_BAD_PARAMETER);
85 	}
86 
87 	for (i = 0; i < UUID_BUFFER_LENGTH; i++) {
88 		out_string[acpi_gbl_map_to_uuid_offset[i]] =
89 		    acpi_ut_hex_to_ascii_char(uuid_buffer[i], 4);
90 
91 		out_string[acpi_gbl_map_to_uuid_offset[i] + 1] =
92 		    acpi_ut_hex_to_ascii_char(uuid_buffer[i], 0);
93 	}
94 
95 	/* Insert required hyphens (dashes) */
96 
97 	out_string[UUID_HYPHEN1_OFFSET] =
98 	    out_string[UUID_HYPHEN2_OFFSET] =
99 	    out_string[UUID_HYPHEN3_OFFSET] =
100 	    out_string[UUID_HYPHEN4_OFFSET] = '-';
101 
102 	out_string[UUID_STRING_LENGTH] = 0;	/* Null terminate */
103 	return (AE_OK);
104 }
105 #endif
106