xref: /freebsd/lib/libefivar/efivar-dp.h (revision b00ab754)
1 /*-
2  * Copyright (c) 2017 Netflix, Inc.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #ifndef	_EFIVAR_DP_H_
30 #define	_EFIVAR_DP_H_
31 
32 /*
33  * "Linux compatible" efivar-dp.h header. At the moment, it's really a
34  * very thin, minimal interface.
35  */
36 
37 /*
38  * Generic EFI_DEVICE_PATH, spelled the Linux way. We use this
39  * interface to the outside world and type-pun to the EFI EDK2 code
40  * we use to implement it.
41  */
42 typedef struct {
43 	uint8_t type;
44 	uint8_t subtype;
45 	uint16_t length;
46 } __packed efidp_header;
47 
48 /* NB: Linux has shadow types for all dp type */
49 
50 typedef union {
51         efidp_header header;
52 } efidp_data;
53 typedef efidp_data *efidp;
54 typedef const efidp_data *const_efidp;
55 
56 /** format a device path into UEFI standard conforming output.
57  *
58  * NB: FreeBSD's implementation is taken from EDK2, while Linux's
59  * was hand-rolled. There may be differences as a result.
60  */
61 ssize_t efidp_format_device_path(char *buf, size_t len, const_efidp dp,
62     ssize_t max);
63 ssize_t efidp_format_device_path_node(char *buf, size_t len, const_efidp dp);
64 ssize_t efidp_parse_device_path(char *path, efidp out, size_t max);
65 char * efidp_extract_file_path(const_efidp dp);
66 
67 size_t efidp_size(const_efidp);
68 
69 int efivar_device_path_to_unix_path(const_efidp dp, char **dev, char **relpath, char **abspath);
70 int efivar_unix_path_to_device_path(const char *path, efidp *dp);
71 
72 #endif /* _EFIVAR_DP_H_ */
73