xref: /freebsd/lib/libefivar/efivar-dp.h (revision bdd1243df58e60e85101c09001d9812a789b6bc4)
1 /*-
2  * Copyright (c) 2017 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  * $FreeBSD$
26  */
27 
28 #ifndef	_EFIVAR_DP_H_
29 #define	_EFIVAR_DP_H_
30 
31 /*
32  * "Linux compatible" efivar-dp.h header. At the moment, it's really a
33  * very thin, minimal interface.
34  */
35 
36 /*
37  * Generic EFI_DEVICE_PATH, spelled the Linux way. We use this
38  * interface to the outside world and type-pun to the EFI EDK2 code
39  * we use to implement it.
40  */
41 typedef struct {
42 	uint8_t type;
43 	uint8_t subtype;
44 	uint16_t length;
45 } __packed efidp_header;
46 
47 /* NB: Linux has shadow types for all dp type */
48 
49 typedef union {
50         efidp_header header;
51 } efidp_data;
52 typedef efidp_data *efidp;
53 typedef const efidp_data *const_efidp;
54 
55 /** format a device path into UEFI standard conforming output.
56  *
57  * NB: FreeBSD's implementation is taken from EDK2, while Linux's
58  * was hand-rolled. There may be differences as a result.
59  */
60 ssize_t efidp_format_device_path(char *buf, size_t len, const_efidp dp,
61     ssize_t max);
62 ssize_t efidp_format_device_path_node(char *buf, size_t len, const_efidp dp);
63 ssize_t efidp_parse_device_path(char *path, efidp out, size_t max);
64 char * efidp_extract_file_path(const_efidp dp);
65 
66 size_t efidp_size(const_efidp);
67 
68 int efivar_device_path_to_unix_path(const_efidp dp, char **dev, char **relpath, char **abspath);
69 int efivar_unix_path_to_device_path(const char *path, efidp *dp);
70 
71 #endif /* _EFIVAR_DP_H_ */
72