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 */ 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/conf.h> 48 #include <sys/errno.h> 49 #include <sys/fcntl.h> 50 #include <sys/ioccom.h> 51 #include <sys/kernel.h> 52 #include <sys/malloc.h> 53 #include <sys/module.h> 54 55 #include <dev/ofw/openfirmio.h> 56 57 static struct cdev *openfirm_dev; 58 59 static d_ioctl_t openfirm_ioctl; 60 61 #define OPENFIRM_MINOR 0 62 63 static struct cdevsw openfirm_cdevsw = { 64 .d_version = D_VERSION, 65 .d_flags = D_NEEDGIANT | D_GIANTOK, 66 .d_ioctl = openfirm_ioctl, 67 .d_name = "openfirm", 68 }; 69 70 static phandle_t lastnode; /* speed hack */ 71 72 static int openfirm_checkid(phandle_t, phandle_t); 73 static int openfirm_getstr(int, const char *, char **); 74 75 /* 76 * Verify target ID is valid (exists in the OPENPROM tree), as 77 * listed from node ID sid forward. 78 */ 79 static int 80 openfirm_checkid(phandle_t sid, phandle_t tid) 81 { 82 83 for (; sid != 0; sid = OF_peer(sid)) 84 if (sid == tid || openfirm_checkid(OF_child(sid), tid)) 85 return (1); 86 87 return (0); 88 } 89 90 static int 91 openfirm_getstr(int len, const char *user, char **cpp) 92 { 93 int error; 94 char *cp; 95 96 /* Reject obvious bogus requests. */ 97 if ((u_int)len > OFIOCMAXNAME) 98 return (ENAMETOOLONG); 99 100 *cpp = cp = malloc(len + 1, M_TEMP, M_WAITOK); 101 error = copyin(user, cp, len); 102 cp[len] = '\0'; 103 return (error); 104 } 105 106 int 107 openfirm_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, 108 struct thread *td) 109 { 110 struct ofiocdesc *of; 111 phandle_t node; 112 int len, ok, error; 113 char *name, *value; 114 char newname[OFIOCSUGGPROPNAMELEN]; 115 116 if ((flags & FREAD) == 0) 117 return (EBADF); 118 119 of = (struct ofiocdesc *)data; 120 switch (cmd) { 121 case OFIOCGETOPTNODE: 122 *(phandle_t *) data = OF_finddevice("/options"); 123 return (0); 124 case OFIOCGET: 125 case OFIOCSET: 126 case OFIOCNEXTPROP: 127 case OFIOCFINDDEVICE: 128 case OFIOCGETPROPLEN: 129 node = of->of_nodeid; 130 break; 131 case OFIOCGETNEXT: 132 case OFIOCGETCHILD: 133 node = *(phandle_t *)data; 134 break; 135 default: 136 return (ENOIOCTL); 137 } 138 139 if (node != 0 && node != lastnode) { 140 /* Not an easy one, we must search for it. */ 141 ok = openfirm_checkid(OF_peer(0), node); 142 if (!ok) 143 return (EINVAL); 144 lastnode = node; 145 } 146 147 name = value = NULL; 148 error = 0; 149 switch (cmd) { 150 case OFIOCGET: 151 case OFIOCGETPROPLEN: 152 if (node == 0) 153 return (EINVAL); 154 error = openfirm_getstr(of->of_namelen, of->of_name, &name); 155 if (error) 156 break; 157 len = OF_getproplen(node, name); 158 if (cmd == OFIOCGETPROPLEN) { 159 of->of_buflen = len; 160 break; 161 } 162 if (len > of->of_buflen) { 163 error = ENOMEM; 164 break; 165 } 166 of->of_buflen = len; 167 /* -1 means no entry; 0 means no value. */ 168 if (len <= 0) 169 break; 170 value = malloc(len, M_TEMP, M_WAITOK); 171 len = OF_getprop(node, name, (void *)value, len); 172 error = copyout(value, of->of_buf, len); 173 break; 174 175 case OFIOCSET: 176 /* 177 * Note: Text string values for at least the /options node 178 * have to be null-terminated and the length parameter must 179 * include this terminating null. However, like OF_getprop(), 180 * OF_setprop() will return the actual length of the text 181 * string, i.e. omitting the terminating null. 182 */ 183 if ((flags & FWRITE) == 0) 184 return (EBADF); 185 if (node == 0) 186 return (EINVAL); 187 if ((u_int)of->of_buflen > OFIOCMAXVALUE) 188 return (ENAMETOOLONG); 189 error = openfirm_getstr(of->of_namelen, of->of_name, &name); 190 if (error) 191 break; 192 value = malloc(of->of_buflen, M_TEMP, M_WAITOK); 193 error = copyin(of->of_buf, value, of->of_buflen); 194 if (error) 195 break; 196 len = OF_setprop(node, name, value, of->of_buflen); 197 if (len < 0) 198 error = EINVAL; 199 of->of_buflen = len; 200 break; 201 202 case OFIOCNEXTPROP: 203 if (node == 0 || of->of_buflen < 0) 204 return (EINVAL); 205 if (of->of_namelen != 0) { 206 error = openfirm_getstr(of->of_namelen, of->of_name, 207 &name); 208 if (error) 209 break; 210 } 211 ok = OF_nextprop(node, name, newname, sizeof(newname)); 212 if (ok == 0) { 213 error = ENOENT; 214 break; 215 } 216 if (ok == -1) { 217 error = EINVAL; 218 break; 219 } 220 len = strlen(newname) + 1; 221 if (len > of->of_buflen) { 222 /* 223 * Passed buffer was insufficient. 224 * 225 * Instead of returning an error here, truncate the 226 * property name to fit the buffer. 227 * 228 * This allows us to retain compatibility with old 229 * tools which always pass a 32 character buffer. 230 */ 231 len = of->of_buflen; 232 newname[len - 1] = '\0'; 233 } 234 else 235 of->of_buflen = len; 236 error = copyout(newname, of->of_buf, len); 237 break; 238 239 case OFIOCGETNEXT: 240 node = OF_peer(node); 241 *(phandle_t *)data = lastnode = node; 242 break; 243 244 case OFIOCGETCHILD: 245 if (node == 0) 246 return (EINVAL); 247 node = OF_child(node); 248 *(phandle_t *)data = lastnode = node; 249 break; 250 251 case OFIOCFINDDEVICE: 252 error = openfirm_getstr(of->of_namelen, of->of_name, &name); 253 if (error) 254 break; 255 node = OF_finddevice(name); 256 if (node == -1) { 257 error = ENOENT; 258 break; 259 } 260 of->of_nodeid = lastnode = node; 261 break; 262 } 263 264 if (name != NULL) 265 free(name, M_TEMP); 266 if (value != NULL) 267 free(value, M_TEMP); 268 269 return (error); 270 } 271 272 static int 273 openfirm_modevent(module_t mod, int type, void *data) 274 { 275 276 switch(type) { 277 case MOD_LOAD: 278 if (bootverbose) 279 printf("openfirm: <Open Firmware control device>\n"); 280 /* 281 * Allow only root access by default; this device may allow 282 * users to peek into firmware passwords, and likely to crash 283 * the machine on some boxen due to firmware quirks. 284 */ 285 openfirm_dev = make_dev(&openfirm_cdevsw, OPENFIRM_MINOR, 286 UID_ROOT, GID_WHEEL, 0600, "openfirm"); 287 return 0; 288 289 case MOD_UNLOAD: 290 destroy_dev(openfirm_dev); 291 return 0; 292 293 case MOD_SHUTDOWN: 294 return 0; 295 296 default: 297 return EOPNOTSUPP; 298 } 299 } 300 301 DEV_MODULE(openfirm, openfirm_modevent, NULL); 302