xref: /freebsd/stand/efi/libefi/efienv.c (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*-
2  * Copyright (c) 2018 Netflix, Inc.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <stand.h>
30 #include <efi.h>
31 #include <efichar.h>
32 #include <efilib.h>
33 
34 static EFI_GUID FreeBSDBootVarGUID = FREEBSD_BOOT_VAR_GUID;
35 static EFI_GUID GlobalBootVarGUID = EFI_GLOBAL_VARIABLE;
36 
37 EFI_STATUS
38 efi_getenv(EFI_GUID *g, const char *v, void *data, size_t *len)
39 {
40 	size_t ul;
41 	CHAR16 *uv;
42 	UINT32 attr;
43 	UINTN dl;
44 	EFI_STATUS rv;
45 
46 	uv = NULL;
47 	if (utf8_to_ucs2(v, &uv, &ul) != 0)
48 		return (EFI_OUT_OF_RESOURCES);
49 	dl = *len;
50 	rv = RS->GetVariable(uv, g, &attr, &dl, data);
51 	if (rv == EFI_SUCCESS || rv == EFI_BUFFER_TOO_SMALL)
52 		*len = dl;
53 	free(uv);
54 	return (rv);
55 }
56 
57 EFI_STATUS
58 efi_global_getenv(const char *v, void *data, size_t *len)
59 {
60 
61 	return (efi_getenv(&GlobalBootVarGUID, v, data, len));
62 }
63 
64 EFI_STATUS
65 efi_freebsd_getenv(const char *v, void *data, size_t *len)
66 {
67 
68 	return (efi_getenv(&FreeBSDBootVarGUID, v, data, len));
69 }
70 
71 /*
72  * efi_setenv -- Sets an env variable.
73  */
74 EFI_STATUS
75 efi_setenv(EFI_GUID *guid, const char *varname, UINT32 attr, void *data, __size_t len)
76 {
77 	EFI_STATUS rv;
78 	CHAR16 *uv;
79 	size_t ul;
80 
81 	uv = NULL;
82 	if (utf8_to_ucs2(varname, &uv, &ul) != 0)
83 		return (EFI_OUT_OF_RESOURCES);
84 
85 	rv = RS->SetVariable(uv, guid, attr, len, data);
86 	free(uv);
87 	return (rv);
88 }
89 
90 EFI_STATUS
91 efi_setenv_freebsd_wcs(const char *varname, CHAR16 *valstr)
92 {
93 	CHAR16 *var = NULL;
94 	size_t len;
95 	EFI_STATUS rv;
96 
97 	if (utf8_to_ucs2(varname, &var, &len) != 0)
98 		return (EFI_OUT_OF_RESOURCES);
99 	rv = RS->SetVariable(var, &FreeBSDBootVarGUID,
100 	    EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS,
101 	    (ucs2len(valstr) + 1) * sizeof(efi_char), valstr);
102 	free(var);
103 	return (rv);
104 }
105 
106 /*
107  * efi_delenv -- deletes the specified env variable
108  */
109 EFI_STATUS
110 efi_delenv(EFI_GUID *guid, const char *name)
111 {
112 	CHAR16 *var;
113 	size_t len;
114 	EFI_STATUS rv;
115 
116 	var = NULL;
117 	if (utf8_to_ucs2(name, &var, &len) != 0)
118 		return (EFI_OUT_OF_RESOURCES);
119 
120 	rv = RS->SetVariable(var, guid, 0, 0, NULL);
121 	free(var);
122 	return (rv);
123 }
124 
125 EFI_STATUS
126 efi_freebsd_delenv(const char *name)
127 {
128 	return (efi_delenv(&FreeBSDBootVarGUID, name));
129 }
130