1 /* $NetBSD: openfirmio.c,v 1.4 2002/09/06 13:23:19 gehenna Exp $ */
2
3 #include <sys/cdefs.h>
4 /*-
5 * SPDX-License-Identifier: BSD-3-Clause
6 *
7 * Copyright (c) 1992, 1993
8 * The Regents of the University of California. All rights reserved.
9 *
10 * This software was developed by the Computer Systems Engineering group
11 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
12 * contributed to Berkeley.
13 *
14 * All advertising materials mentioning features or use of this software
15 * must display the following acknowledgement:
16 * This product includes software developed by the University of
17 * California, Lawrence Berkeley Laboratory.
18 *
19 * Redistribution and use in source and binary forms, with or without
20 * modification, are permitted provided that the following conditions
21 * are met:
22 * 1. Redistributions of source code must retain the above copyright
23 * notice, this list of conditions and the following disclaimer.
24 * 2. Redistributions in binary form must reproduce the above copyright
25 * notice, this list of conditions and the following disclaimer in the
26 * documentation and/or other materials provided with the distribution.
27 * 3. Neither the name of the University nor the names of its contributors
28 * may be used to endorse or promote products derived from this software
29 * without specific prior written permission.
30 *
31 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
32 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
33 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
35 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
39 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
40 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
41 * SUCH DAMAGE.
42 *
43 * @(#)openfirm.c 8.1 (Berkeley) 6/11/93
44 *
45 */
46
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/conf.h>
50 #include <sys/errno.h>
51 #include <sys/fcntl.h>
52 #include <sys/ioccom.h>
53 #include <sys/kernel.h>
54 #include <sys/malloc.h>
55 #include <sys/module.h>
56
57 #include <dev/ofw/openfirmio.h>
58
59 static struct cdev *openfirm_dev;
60
61 static d_ioctl_t openfirm_ioctl;
62
63 #define OPENFIRM_MINOR 0
64
65 static struct cdevsw openfirm_cdevsw = {
66 .d_version = D_VERSION,
67 .d_flags = D_NEEDGIANT | D_GIANTOK,
68 .d_ioctl = openfirm_ioctl,
69 .d_name = "openfirm",
70 };
71
72 static phandle_t lastnode; /* speed hack */
73
74 static int openfirm_checkid(phandle_t, phandle_t);
75 static int openfirm_getstr(int, const char *, char **);
76
77 /*
78 * Verify target ID is valid (exists in the OPENPROM tree), as
79 * listed from node ID sid forward.
80 */
81 static int
openfirm_checkid(phandle_t sid,phandle_t tid)82 openfirm_checkid(phandle_t sid, phandle_t tid)
83 {
84
85 for (; sid != 0; sid = OF_peer(sid))
86 if (sid == tid || openfirm_checkid(OF_child(sid), tid))
87 return (1);
88
89 return (0);
90 }
91
92 static int
openfirm_getstr(int len,const char * user,char ** cpp)93 openfirm_getstr(int len, const char *user, char **cpp)
94 {
95 int error;
96 char *cp;
97
98 /* Reject obvious bogus requests. */
99 if ((u_int)len > OFIOCMAXNAME)
100 return (ENAMETOOLONG);
101
102 *cpp = cp = malloc(len + 1, M_TEMP, M_WAITOK);
103 error = copyin(user, cp, len);
104 cp[len] = '\0';
105 return (error);
106 }
107
108 int
openfirm_ioctl(struct cdev * dev,u_long cmd,caddr_t data,int flags,struct thread * td)109 openfirm_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags,
110 struct thread *td)
111 {
112 struct ofiocdesc *of;
113 phandle_t node;
114 int len, ok, error;
115 char *name, *value;
116 char newname[OFIOCSUGGPROPNAMELEN];
117
118 if ((flags & FREAD) == 0)
119 return (EBADF);
120
121 of = (struct ofiocdesc *)data;
122 switch (cmd) {
123 case OFIOCGETOPTNODE:
124 *(phandle_t *) data = OF_finddevice("/options");
125 return (0);
126 case OFIOCGET:
127 case OFIOCSET:
128 case OFIOCNEXTPROP:
129 case OFIOCFINDDEVICE:
130 case OFIOCGETPROPLEN:
131 node = of->of_nodeid;
132 break;
133 case OFIOCGETNEXT:
134 case OFIOCGETCHILD:
135 node = *(phandle_t *)data;
136 break;
137 default:
138 return (ENOIOCTL);
139 }
140
141 if (node != 0 && node != lastnode) {
142 /* Not an easy one, we must search for it. */
143 ok = openfirm_checkid(OF_peer(0), node);
144 if (!ok)
145 return (EINVAL);
146 lastnode = node;
147 }
148
149 name = value = NULL;
150 error = 0;
151 switch (cmd) {
152 case OFIOCGET:
153 case OFIOCGETPROPLEN:
154 if (node == 0)
155 return (EINVAL);
156 error = openfirm_getstr(of->of_namelen, of->of_name, &name);
157 if (error)
158 break;
159 len = OF_getproplen(node, name);
160 if (cmd == OFIOCGETPROPLEN) {
161 of->of_buflen = len;
162 break;
163 }
164 if (len > of->of_buflen) {
165 error = ENOMEM;
166 break;
167 }
168 of->of_buflen = len;
169 /* -1 means no entry; 0 means no value. */
170 if (len <= 0)
171 break;
172 value = malloc(len, M_TEMP, M_WAITOK);
173 len = OF_getprop(node, name, (void *)value, len);
174 error = copyout(value, of->of_buf, len);
175 break;
176
177 case OFIOCSET:
178 /*
179 * Note: Text string values for at least the /options node
180 * have to be null-terminated and the length parameter must
181 * include this terminating null. However, like OF_getprop(),
182 * OF_setprop() will return the actual length of the text
183 * string, i.e. omitting the terminating null.
184 */
185 if ((flags & FWRITE) == 0)
186 return (EBADF);
187 if (node == 0)
188 return (EINVAL);
189 if ((u_int)of->of_buflen > OFIOCMAXVALUE)
190 return (ENAMETOOLONG);
191 error = openfirm_getstr(of->of_namelen, of->of_name, &name);
192 if (error)
193 break;
194 value = malloc(of->of_buflen, M_TEMP, M_WAITOK);
195 error = copyin(of->of_buf, value, of->of_buflen);
196 if (error)
197 break;
198 len = OF_setprop(node, name, value, of->of_buflen);
199 if (len < 0)
200 error = EINVAL;
201 of->of_buflen = len;
202 break;
203
204 case OFIOCNEXTPROP:
205 if (node == 0 || of->of_buflen < 0)
206 return (EINVAL);
207 if (of->of_namelen != 0) {
208 error = openfirm_getstr(of->of_namelen, of->of_name,
209 &name);
210 if (error)
211 break;
212 }
213 ok = OF_nextprop(node, name, newname, sizeof(newname));
214 if (ok == 0) {
215 error = ENOENT;
216 break;
217 }
218 if (ok == -1) {
219 error = EINVAL;
220 break;
221 }
222 len = strlen(newname) + 1;
223 if (len > of->of_buflen) {
224 /*
225 * Passed buffer was insufficient.
226 *
227 * Instead of returning an error here, truncate the
228 * property name to fit the buffer.
229 *
230 * This allows us to retain compatibility with old
231 * tools which always pass a 32 character buffer.
232 */
233 len = of->of_buflen;
234 newname[len - 1] = '\0';
235 }
236 else
237 of->of_buflen = len;
238 error = copyout(newname, of->of_buf, len);
239 break;
240
241 case OFIOCGETNEXT:
242 node = OF_peer(node);
243 *(phandle_t *)data = lastnode = node;
244 break;
245
246 case OFIOCGETCHILD:
247 if (node == 0)
248 return (EINVAL);
249 node = OF_child(node);
250 *(phandle_t *)data = lastnode = node;
251 break;
252
253 case OFIOCFINDDEVICE:
254 error = openfirm_getstr(of->of_namelen, of->of_name, &name);
255 if (error)
256 break;
257 node = OF_finddevice(name);
258 if (node == -1) {
259 error = ENOENT;
260 break;
261 }
262 of->of_nodeid = lastnode = node;
263 break;
264 }
265
266 if (name != NULL)
267 free(name, M_TEMP);
268 if (value != NULL)
269 free(value, M_TEMP);
270
271 return (error);
272 }
273
274 static int
openfirm_modevent(module_t mod,int type,void * data)275 openfirm_modevent(module_t mod, int type, void *data)
276 {
277
278 switch(type) {
279 case MOD_LOAD:
280 if (bootverbose)
281 printf("openfirm: <Open Firmware control device>\n");
282 /*
283 * Allow only root access by default; this device may allow
284 * users to peek into firmware passwords, and likely to crash
285 * the machine on some boxen due to firmware quirks.
286 */
287 openfirm_dev = make_dev(&openfirm_cdevsw, OPENFIRM_MINOR,
288 UID_ROOT, GID_WHEEL, 0600, "openfirm");
289 return 0;
290
291 case MOD_UNLOAD:
292 destroy_dev(openfirm_dev);
293 return 0;
294
295 case MOD_SHUTDOWN:
296 return 0;
297
298 default:
299 return EOPNOTSUPP;
300 }
301 }
302
303 DEV_MODULE(openfirm, openfirm_modevent, NULL);
304