xref: /trueos/lib/libefi/libefi.c (revision 834fb25a9ed2240101506d137b5be7d71c75f306)
1 /*-
2  * Copyright (c) 2010 Marcel Moolenaar
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 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/ioctl.h>
31 #include <sys/types.h>
32 #include <fcntl.h>
33 #include <stddef.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <unistd.h>
37 
38 #include "libefi_int.h"
39 
40 static int __iofd = -1;
41 
42 static void
iodev_fd_close(void)43 iodev_fd_close(void)
44 {
45 
46 	close(__iofd);
47 }
48 
49 static int
iodev_fd(int * fd)50 iodev_fd(int *fd)
51 {
52 
53 	*fd = __iofd;
54 	if (__iofd != -1)
55 		return (0);
56 
57 	__iofd = open("/dev/io", O_RDWR);
58 	if (__iofd == -1)
59 		return (errno);
60 
61 	atexit(iodev_fd_close);
62 	*fd = __iofd;
63 	return (0);
64 }
65 
66 int
libefi_ucs2_to_utf8(u_short * nm,size_t * szp,char * name)67 libefi_ucs2_to_utf8(u_short *nm, size_t *szp, char *name)
68 {
69 	size_t len, sz;
70 	u_short c;
71 
72 	len = 0;
73 	sz = *szp;
74 	while (*nm) {
75 		c = *nm++;
76 		if (c > 0x7ff) {
77 			if (len++ < sz)
78 				*name++ = 0xE0 | (c >> 12);
79 			if (len++ < sz)
80 				*name++ = 0x80 | ((c >> 6) & 0x3f);
81 			if (len++ < sz)
82 				*name++ = 0x80 | (c & 0x3f);
83 		} else if (c > 0x7f) {
84 			if (len++ < sz)
85 				*name++ = 0xC0 | ((c >> 6) & 0x1f);
86 			if (len++ < sz)
87 				*name++ = 0x80 | (c & 0x3f);
88 		} else {
89 			if (len++ < sz)
90 				*name++ = (c & 0x7f);
91 		}
92 	}
93 	if (len++ < sz)
94 		*name++ = 0;
95 
96 	*szp = len;
97 	return ((len <= sz) ? 0 : EOVERFLOW);
98 }
99 
100 int
libefi_utf8_to_ucs2(char * name,size_t * szp,u_short ** nmp)101 libefi_utf8_to_ucs2(char *name, size_t *szp, u_short **nmp)
102 {
103 	u_short *nm;
104 	size_t sz;
105 	uint32_t ucs4;
106 	int c, bytes;
107 
108 	*szp = sz = (*szp == 0) ? strlen(name) * 2 + 2 : *szp;
109 	*nmp = nm = malloc(sz);
110 
111 	ucs4 = 0;
112 	bytes = 0;
113 	while (sz > 1 && *name != '\0') {
114 		c = *name++;
115 		/*
116 		 * Conditionalize on the two major character types:
117 		 * initial and followup characters.
118 		 */
119 		if ((c & 0xc0) != 0x80) {
120 			/* Initial characters. */
121 			if (bytes != 0) {
122 				free(nm);
123 				return (EILSEQ);
124 			}
125 			if ((c & 0xf8) == 0xf0) {
126 				ucs4 = c & 0x07;
127 				bytes = 3;
128 			} else if ((c & 0xf0) == 0xe0) {
129 				ucs4 = c & 0x0f;
130 				bytes = 2;
131 			} else if ((c & 0xe0) == 0xc0) {
132 				ucs4 = c & 0x1f;
133 				bytes = 1;
134 			} else {
135 				ucs4 = c & 0x7f;
136 				bytes = 0;
137 			}
138 		} else {
139 			/* Followup characters. */
140 			if (bytes > 0) {
141 				ucs4 = (ucs4 << 6) + (c & 0x3f);
142 				bytes--;
143 			} else if (bytes == 0) {
144 				free(nm);
145 				return (EILSEQ);
146 			}
147 		}
148 		if (bytes == 0) {
149 			if (ucs4 > 0xffff) {
150 				free(nm);
151 				return (EILSEQ);
152 			}
153 			*nm++ = (u_short)ucs4;
154 			sz -= 2;
155 		}
156 	}
157 	if (sz < 2) {
158 		free(nm);
159 		return (EDOOFUS);
160 	}
161 	*nm = 0;
162 	return (0);
163 }
164 
165 int
libefi_efivar(struct iodev_efivar_req * req)166 libefi_efivar(struct iodev_efivar_req *req)
167 {
168 	int error, fd;
169 
170 	error = iodev_fd(&fd);
171 	if (!error)
172 		error = (ioctl(fd, IODEV_EFIVAR, req) == -1) ? errno : 0;
173 	if (!error)
174 		error = req->result;
175 	return (error);
176 }
177