1 /* $NetBSD: firmload.c,v 1.19 2014/03/25 16:19:13 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2005, 2006 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: firmload.c,v 1.19 2014/03/25 16:19:13 christos Exp $"); 34 35 /* 36 * The firmload API provides an interface for device drivers to access 37 * firmware images that must be loaded onto their devices. 38 */ 39 40 #include <sys/param.h> 41 #include <sys/fcntl.h> 42 #include <sys/filedesc.h> 43 #include <sys/malloc.h> 44 #include <sys/namei.h> 45 #include <sys/systm.h> 46 #include <sys/sysctl.h> 47 #include <sys/vnode.h> 48 #include <sys/kauth.h> 49 #include <sys/lwp.h> 50 51 #include <dev/firmload.h> 52 53 MALLOC_DEFINE(M_DEVFIRM, "devfirm", "device firmware buffers"); 54 55 struct firmware_handle { 56 struct vnode *fh_vp; 57 off_t fh_size; 58 }; 59 60 static firmware_handle_t 61 firmware_handle_alloc(void) 62 { 63 64 return (malloc(sizeof(struct firmware_handle), M_DEVFIRM, M_WAITOK)); 65 } 66 67 static void 68 firmware_handle_free(firmware_handle_t fh) 69 { 70 71 free(fh, M_DEVFIRM); 72 } 73 74 #if !defined(FIRMWARE_PATHS) 75 #define FIRMWARE_PATHS \ 76 "/libdata/firmware:/usr/libdata/firmware:/usr/pkg/libdata/firmware:/usr/pkg/libdata" 77 #endif 78 79 static char firmware_paths[PATH_MAX+1] = FIRMWARE_PATHS; 80 81 static int 82 sysctl_hw_firmware_path(SYSCTLFN_ARGS) 83 { 84 int error, i; 85 char newpath[PATH_MAX+1]; 86 struct sysctlnode node; 87 char expected_char; 88 89 node = *rnode; 90 node.sysctl_data = &newpath[0]; 91 memcpy(node.sysctl_data, rnode->sysctl_data, PATH_MAX+1); 92 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 93 if (error || newp == NULL) 94 return (error); 95 96 /* 97 * Make sure that all of the paths in the new path list are 98 * absolute. 99 * 100 * When sysctl_lookup() deals with a string, it's guaranteed 101 * to come back nul-terminated. 102 */ 103 expected_char = '/'; 104 for (i = 0; i < PATH_MAX+1; i++) { 105 if (expected_char != 0 && newpath[i] != expected_char) 106 return (EINVAL); 107 if (newpath[i] == '\0') 108 break; 109 else if (newpath[i] == ':') 110 expected_char = '/'; 111 else 112 expected_char = 0; 113 } 114 115 memcpy(rnode->sysctl_data, node.sysctl_data, PATH_MAX+1); 116 117 return (0); 118 } 119 120 SYSCTL_SETUP_PROTO(sysctl_hw_firmware_setup); 121 122 SYSCTL_SETUP(sysctl_hw_firmware_setup, "sysctl hw.firmware subtree setup") 123 { 124 const struct sysctlnode *firmware_node; 125 126 if (sysctl_createv(clog, 0, NULL, &firmware_node, 127 CTLFLAG_PERMANENT, 128 CTLTYPE_NODE, "firmware", NULL, 129 NULL, 0, NULL, 0, 130 CTL_HW, CTL_CREATE, CTL_EOL) != 0) 131 return; 132 133 sysctl_createv(clog, 0, NULL, NULL, 134 CTLFLAG_READWRITE, 135 CTLTYPE_STRING, "path", 136 SYSCTL_DESCR("Device firmware loading path list"), 137 sysctl_hw_firmware_path, 0, firmware_paths, PATH_MAX+1, 138 CTL_HW, firmware_node->sysctl_num, CTL_CREATE, CTL_EOL); 139 } 140 141 static char * 142 firmware_path_next(const char *drvname, const char *imgname, char *pnbuf, 143 char **prefixp) 144 { 145 char *prefix = *prefixp; 146 size_t maxprefix, i; 147 148 if (prefix == NULL /* terminated early */ 149 || *prefix == '\0' /* no more left */ 150 || *prefix != '/') { /* not absolute */ 151 *prefixp = NULL; 152 return (NULL); 153 } 154 155 /* 156 * Compute the max path prefix based on the length of the provided 157 * names. 158 */ 159 maxprefix = MAXPATHLEN - 160 (1 /* / */ 161 + strlen(drvname) 162 + 1 /* / */ 163 + strlen(imgname) 164 + 1 /* terminating NUL */); 165 166 /* Check for underflow (size_t is unsigned). */ 167 if (maxprefix > MAXPATHLEN) { 168 *prefixp = NULL; 169 return (NULL); 170 } 171 172 for (i = 0; i < maxprefix; i++) { 173 if (*prefix == ':' || *prefix == '\0') 174 break; 175 pnbuf[i] = *prefix++; 176 } 177 178 if (*prefix != ':' && *prefix != '\0') { 179 /* Path prefix was too long. */ 180 *prefixp = NULL; 181 return (NULL); 182 } 183 184 if (*prefix != '\0') 185 prefix++; 186 *prefixp = prefix; 187 188 KASSERT(MAXPATHLEN >= i); 189 snprintf(pnbuf + i, MAXPATHLEN - i, "/%s/%s", drvname, imgname); 190 191 return (pnbuf); 192 } 193 194 static char * 195 firmware_path_first(const char *drvname, const char *imgname, char *pnbuf, 196 char **prefixp) 197 { 198 199 *prefixp = firmware_paths; 200 return (firmware_path_next(drvname, imgname, pnbuf, prefixp)); 201 } 202 203 /* 204 * firmware_open: 205 * 206 * Open a firmware image and return its handle. 207 */ 208 int 209 firmware_open(const char *drvname, const char *imgname, firmware_handle_t *fhp) 210 { 211 struct pathbuf *pb; 212 struct nameidata nd; 213 struct vattr va; 214 char *pnbuf, *path, *prefix; 215 firmware_handle_t fh; 216 struct vnode *vp; 217 int error; 218 extern struct cwdinfo cwdi0; 219 220 if (drvname == NULL || imgname == NULL) 221 return (EINVAL); 222 223 if (cwdi0.cwdi_cdir == NULL) { 224 printf("firmware_open(%s/%s) called too early.\n", 225 drvname, imgname); 226 return ENOENT; 227 } 228 229 pnbuf = PNBUF_GET(); 230 KASSERT(pnbuf != NULL); 231 232 fh = firmware_handle_alloc(); 233 KASSERT(fh != NULL); 234 235 error = 0; 236 for (path = firmware_path_first(drvname, imgname, pnbuf, &prefix); 237 path != NULL; 238 path = firmware_path_next(drvname, imgname, pnbuf, &prefix)) { 239 pb = pathbuf_create(path); 240 if (pb == NULL) { 241 error = ENOMEM; 242 break; 243 } 244 NDINIT(&nd, LOOKUP, FOLLOW | NOCHROOT, pb); 245 error = vn_open(&nd, FREAD, 0); 246 pathbuf_destroy(pb); 247 if (error == ENOENT) { 248 continue; 249 } 250 break; 251 } 252 253 PNBUF_PUT(pnbuf); 254 if (error) { 255 firmware_handle_free(fh); 256 return (error); 257 } 258 259 vp = nd.ni_vp; 260 261 error = VOP_GETATTR(vp, &va, kauth_cred_get()); 262 if (error) { 263 VOP_UNLOCK(vp); 264 (void)vn_close(vp, FREAD, kauth_cred_get()); 265 firmware_handle_free(fh); 266 return (error); 267 } 268 269 if (va.va_type != VREG) { 270 VOP_UNLOCK(vp); 271 (void)vn_close(vp, FREAD, kauth_cred_get()); 272 firmware_handle_free(fh); 273 return (EINVAL); 274 } 275 276 /* XXX Mark as busy text file. */ 277 278 fh->fh_vp = vp; 279 fh->fh_size = va.va_size; 280 281 VOP_UNLOCK(vp); 282 283 *fhp = fh; 284 return (0); 285 } 286 287 /* 288 * firmware_close: 289 * 290 * Close a firmware image. 291 */ 292 int 293 firmware_close(firmware_handle_t fh) 294 { 295 int error; 296 297 error = vn_close(fh->fh_vp, FREAD, kauth_cred_get()); 298 firmware_handle_free(fh); 299 return (error); 300 } 301 302 /* 303 * firmware_get_size: 304 * 305 * Return the total size of a firmware image. 306 */ 307 off_t 308 firmware_get_size(firmware_handle_t fh) 309 { 310 311 return (fh->fh_size); 312 } 313 314 /* 315 * firmware_read: 316 * 317 * Read data from a firmware image at the specified offset into 318 * the provided buffer. 319 */ 320 int 321 firmware_read(firmware_handle_t fh, off_t offset, void *buf, size_t len) 322 { 323 324 return (vn_rdwr(UIO_READ, fh->fh_vp, buf, len, offset, 325 UIO_SYSSPACE, 0, kauth_cred_get(), NULL, curlwp)); 326 } 327 328 /* 329 * firmware_malloc: 330 * 331 * Allocate a firmware buffer of the specified size. 332 * 333 * NOTE: This routine may block. 334 */ 335 void * 336 firmware_malloc(size_t size) 337 { 338 339 return (malloc(size, M_DEVFIRM, M_WAITOK)); 340 } 341 342 /* 343 * firmware_free: 344 * 345 * Free a previously allocated firmware buffer. 346 */ 347 /*ARGSUSED*/ 348 void 349 firmware_free(void *v, size_t size) 350 { 351 352 free(v, M_DEVFIRM); 353 } 354