1 /*-
2 * Copyright (c) 2016 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 * in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 * $FreeBSD: head/sys/dev/efidev/efidev.c 307391 2016-10-16 06:07:43Z kib $
27 */
28
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/kernel.h>
32 #include <sys/bus.h>
33 #include <sys/conf.h>
34 #include <sys/lock.h>
35 #include <sys/malloc.h>
36 #include <sys/module.h>
37 #include <sys/device.h>
38
39 #include <machine/efi.h>
40 #include <sys/efiio.h>
41
42 static struct lock efidev_lock = LOCK_INITIALIZER("efidev", 0, 0);
43
44 static d_ioctl_t efidev_ioctl;
45 static d_open_t efidev_open;
46 static d_close_t efidev_close;
47
48 static struct dev_ops efi_ops = {
49 { "efi", 0, D_MPSAFE },
50 .d_open = efidev_open,
51 .d_close = efidev_close,
52 .d_ioctl = efidev_ioctl,
53 };
54
55 static int
efidev_open(struct dev_open_args * ap)56 efidev_open(struct dev_open_args *ap)
57 {
58 return 0;
59 }
60
61 static int
efidev_close(struct dev_close_args * ap)62 efidev_close(struct dev_close_args *ap)
63 {
64 return 0;
65 }
66
67 static int
efidev_ioctl(struct dev_ioctl_args * ap)68 efidev_ioctl(struct dev_ioctl_args *ap)
69 {
70 u_long cmd = ap->a_cmd;
71 caddr_t addr = ap->a_data;
72 int error;
73
74 lockmgr(&efidev_lock, LK_EXCLUSIVE);
75
76 switch (cmd) {
77 case EFIIOC_GET_TABLE:
78 {
79 struct efi_get_table_ioc *egtioc =
80 (struct efi_get_table_ioc *)addr;
81
82 error = efi_get_table(&egtioc->uuid, &egtioc->ptr);
83 break;
84 }
85 case EFIIOC_GET_TIME:
86 {
87 struct efi_tm *tm = (struct efi_tm *)addr;
88
89 error = efi_get_time(tm);
90 break;
91 }
92 case EFIIOC_SET_TIME:
93 {
94 struct efi_tm *tm = (struct efi_tm *)addr;
95
96 error = efi_set_time(tm);
97 break;
98 }
99 case EFIIOC_VAR_GET:
100 {
101 struct efi_var_ioc *ev = (struct efi_var_ioc *)addr;
102 void *data;
103 efi_char *name;
104
105 data = kmalloc(ev->datasize, M_TEMP, M_WAITOK);
106 name = kmalloc(ev->namesize, M_TEMP, M_WAITOK);
107 error = copyin(ev->name, name, ev->namesize);
108 if (error)
109 goto vg_out;
110 if (name[ev->namesize / sizeof(efi_char) - 1] != 0) {
111 error = EINVAL;
112 goto vg_out;
113 }
114
115 error = efi_var_get(name, &ev->vendor, &ev->attrib,
116 &ev->datasize, data);
117
118 if (error == 0) {
119 error = copyout(data, ev->data, ev->datasize);
120 } else if (error == EOVERFLOW) {
121 /*
122 * Pass back the size we really need, but
123 * convert the error to 0 so the copyout
124 * happens. datasize was updated in the
125 * efi_var_get call.
126 */
127 ev->data = NULL;
128 error = 0;
129 }
130 vg_out:
131 kfree(data, M_TEMP);
132 kfree(name, M_TEMP);
133 break;
134 }
135 case EFIIOC_VAR_NEXT:
136 {
137 struct efi_var_ioc *ev = (struct efi_var_ioc *)addr;
138 efi_char *name;
139
140 name = kmalloc(ev->namesize, M_TEMP, M_WAITOK);
141 error = copyin(ev->name, name, ev->namesize);
142 if (error)
143 goto vn_out;
144 /* Note: namesize is the buffer size, not the string lenght */
145
146 error = efi_var_nextname(&ev->namesize, name, &ev->vendor);
147 if (error == 0) {
148 error = copyout(name, ev->name, ev->namesize);
149 } else if (error == EOVERFLOW) {
150 ev->name = NULL;
151 error = 0;
152 }
153 vn_out:
154 kfree(name, M_TEMP);
155 break;
156 }
157 case EFIIOC_VAR_SET:
158 {
159 struct efi_var_ioc *ev = (struct efi_var_ioc *)addr;
160 void *data = NULL;
161 efi_char *name;
162
163 /* datasize == 0 -> delete (more or less) */
164 if (ev->datasize > 0)
165 data = kmalloc(ev->datasize, M_TEMP, M_WAITOK);
166 name = kmalloc(ev->namesize, M_TEMP, M_WAITOK);
167 if (ev->datasize) {
168 error = copyin(ev->data, data, ev->datasize);
169 if (error)
170 goto vs_out;
171 }
172 error = copyin(ev->name, name, ev->namesize);
173 if (error)
174 goto vs_out;
175 if (name[ev->namesize / sizeof(efi_char) - 1] != 0) {
176 error = EINVAL;
177 goto vs_out;
178 }
179
180 error = efi_var_set(name, &ev->vendor, ev->attrib, ev->datasize,
181 data);
182 vs_out:
183 if (ev->datasize > 0)
184 kfree(data, M_TEMP);
185 kfree(name, M_TEMP);
186 break;
187 }
188 default:
189 error = ENOTTY;
190 break;
191 }
192
193 lockmgr(&efidev_lock, LK_RELEASE);
194
195 return (error);
196 }
197
198 static struct cdev *efidev;
199
200 static int
efidev_modevents(module_t m,int event,void * arg __unused)201 efidev_modevents(module_t m, int event, void *arg __unused)
202 {
203 switch (event) {
204 case MOD_LOAD:
205 efidev = make_dev(&efi_ops, 0, UID_ROOT, GID_WHEEL,
206 0700, "efi");
207 return (0);
208
209 case MOD_UNLOAD:
210 if (efidev != NULL)
211 destroy_dev(efidev);
212 efidev = NULL;
213 return (0);
214
215 case MOD_SHUTDOWN:
216 return (0);
217
218 default:
219 return (EOPNOTSUPP);
220 }
221 }
222
223 static moduledata_t efidev_moddata = {
224 .name = "efidev",
225 .evhand = efidev_modevents,
226 .priv = NULL,
227 };
228
229 DECLARE_MODULE(efidev, efidev_moddata, SI_SUB_PRE_DRIVERS, SI_ORDER_ANY);
230 MODULE_VERSION(efidev, 1);
231 MODULE_DEPEND(efidev, efirt, 1, 1, 1);
232