1 /* $NetBSD: firmload.c,v 1.21 2015/01/04 19:25:32 pooka 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 1.21 2015/01/04 19:25:32 pooka 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/kmem.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 struct firmware_handle { 54 struct vnode *fh_vp; 55 off_t fh_size; 56 }; 57 58 static firmware_handle_t 59 firmware_handle_alloc(void) 60 { 61 62 return (kmem_alloc(sizeof(struct firmware_handle), KM_SLEEP)); 63 } 64 65 static void 66 firmware_handle_free(firmware_handle_t fh) 67 { 68 69 kmem_free(fh, sizeof(*fh)); 70 } 71 72 #if !defined(FIRMWARE_PATHS) 73 #define FIRMWARE_PATHS \ 74 "/libdata/firmware:/usr/libdata/firmware:/usr/pkg/libdata/firmware:/usr/pkg/libdata" 75 #endif 76 77 static char firmware_paths[PATH_MAX+1] = FIRMWARE_PATHS; 78 79 static int 80 sysctl_hw_firmware_path(SYSCTLFN_ARGS) 81 { 82 int error, i; 83 char newpath[PATH_MAX+1]; 84 struct sysctlnode node; 85 char expected_char; 86 87 node = *rnode; 88 node.sysctl_data = &newpath[0]; 89 memcpy(node.sysctl_data, rnode->sysctl_data, PATH_MAX+1); 90 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 91 if (error || newp == NULL) 92 return (error); 93 94 /* 95 * Make sure that all of the paths in the new path list are 96 * absolute. 97 * 98 * When sysctl_lookup() deals with a string, it's guaranteed 99 * to come back nul-terminated. 100 */ 101 expected_char = '/'; 102 for (i = 0; i < PATH_MAX+1; i++) { 103 if (expected_char != 0 && newpath[i] != expected_char) 104 return (EINVAL); 105 if (newpath[i] == '\0') 106 break; 107 else if (newpath[i] == ':') 108 expected_char = '/'; 109 else 110 expected_char = 0; 111 } 112 113 memcpy(rnode->sysctl_data, node.sysctl_data, PATH_MAX+1); 114 115 return (0); 116 } 117 118 SYSCTL_SETUP(sysctl_hw_firmware_setup, "sysctl hw.firmware subtree setup") 119 { 120 const struct sysctlnode *firmware_node; 121 122 if (sysctl_createv(clog, 0, NULL, &firmware_node, 123 CTLFLAG_PERMANENT, 124 CTLTYPE_NODE, "firmware", NULL, 125 NULL, 0, NULL, 0, 126 CTL_HW, CTL_CREATE, CTL_EOL) != 0) 127 return; 128 129 sysctl_createv(clog, 0, NULL, NULL, 130 CTLFLAG_READWRITE, 131 CTLTYPE_STRING, "path", 132 SYSCTL_DESCR("Device firmware loading path list"), 133 sysctl_hw_firmware_path, 0, firmware_paths, PATH_MAX+1, 134 CTL_HW, firmware_node->sysctl_num, CTL_CREATE, CTL_EOL); 135 } 136 137 static char * 138 firmware_path_next(const char *drvname, const char *imgname, char *pnbuf, 139 char **prefixp) 140 { 141 char *prefix = *prefixp; 142 size_t maxprefix, i; 143 144 if (prefix == NULL /* terminated early */ 145 || *prefix == '\0' /* no more left */ 146 || *prefix != '/') { /* not absolute */ 147 *prefixp = NULL; 148 return (NULL); 149 } 150 151 /* 152 * Compute the max path prefix based on the length of the provided 153 * names. 154 */ 155 maxprefix = MAXPATHLEN - 156 (1 /* / */ 157 + strlen(drvname) 158 + 1 /* / */ 159 + strlen(imgname) 160 + 1 /* terminating NUL */); 161 162 /* Check for underflow (size_t is unsigned). */ 163 if (maxprefix > MAXPATHLEN) { 164 *prefixp = NULL; 165 return (NULL); 166 } 167 168 for (i = 0; i < maxprefix; i++) { 169 if (*prefix == ':' || *prefix == '\0') 170 break; 171 pnbuf[i] = *prefix++; 172 } 173 174 if (*prefix != ':' && *prefix != '\0') { 175 /* Path prefix was too long. */ 176 *prefixp = NULL; 177 return (NULL); 178 } 179 180 if (*prefix != '\0') 181 prefix++; 182 *prefixp = prefix; 183 184 KASSERT(MAXPATHLEN >= i); 185 snprintf(pnbuf + i, MAXPATHLEN - i, "/%s/%s", drvname, imgname); 186 187 return (pnbuf); 188 } 189 190 static char * 191 firmware_path_first(const char *drvname, const char *imgname, char *pnbuf, 192 char **prefixp) 193 { 194 195 *prefixp = firmware_paths; 196 return (firmware_path_next(drvname, imgname, pnbuf, prefixp)); 197 } 198 199 /* 200 * firmware_open: 201 * 202 * Open a firmware image and return its handle. 203 */ 204 int 205 firmware_open(const char *drvname, const char *imgname, firmware_handle_t *fhp) 206 { 207 struct pathbuf *pb; 208 struct nameidata nd; 209 struct vattr va; 210 char *pnbuf, *path, *prefix; 211 firmware_handle_t fh; 212 struct vnode *vp; 213 int error; 214 extern struct cwdinfo cwdi0; 215 216 if (drvname == NULL || imgname == NULL) 217 return (EINVAL); 218 219 if (cwdi0.cwdi_cdir == NULL) { 220 printf("firmware_open(%s/%s) called too early.\n", 221 drvname, imgname); 222 return ENOENT; 223 } 224 225 pnbuf = PNBUF_GET(); 226 KASSERT(pnbuf != NULL); 227 228 fh = firmware_handle_alloc(); 229 KASSERT(fh != NULL); 230 231 error = 0; 232 for (path = firmware_path_first(drvname, imgname, pnbuf, &prefix); 233 path != NULL; 234 path = firmware_path_next(drvname, imgname, pnbuf, &prefix)) { 235 pb = pathbuf_create(path); 236 if (pb == NULL) { 237 error = ENOMEM; 238 break; 239 } 240 NDINIT(&nd, LOOKUP, FOLLOW | NOCHROOT, pb); 241 error = vn_open(&nd, FREAD, 0); 242 pathbuf_destroy(pb); 243 if (error == ENOENT) { 244 continue; 245 } 246 break; 247 } 248 249 PNBUF_PUT(pnbuf); 250 if (error) { 251 firmware_handle_free(fh); 252 return (error); 253 } 254 255 vp = nd.ni_vp; 256 257 error = VOP_GETATTR(vp, &va, kauth_cred_get()); 258 if (error) { 259 VOP_UNLOCK(vp); 260 (void)vn_close(vp, FREAD, kauth_cred_get()); 261 firmware_handle_free(fh); 262 return (error); 263 } 264 265 if (va.va_type != VREG) { 266 VOP_UNLOCK(vp); 267 (void)vn_close(vp, FREAD, kauth_cred_get()); 268 firmware_handle_free(fh); 269 return (EINVAL); 270 } 271 272 /* XXX Mark as busy text file. */ 273 274 fh->fh_vp = vp; 275 fh->fh_size = va.va_size; 276 277 VOP_UNLOCK(vp); 278 279 *fhp = fh; 280 return (0); 281 } 282 283 /* 284 * firmware_close: 285 * 286 * Close a firmware image. 287 */ 288 int 289 firmware_close(firmware_handle_t fh) 290 { 291 int error; 292 293 error = vn_close(fh->fh_vp, FREAD, kauth_cred_get()); 294 firmware_handle_free(fh); 295 return (error); 296 } 297 298 /* 299 * firmware_get_size: 300 * 301 * Return the total size of a firmware image. 302 */ 303 off_t 304 firmware_get_size(firmware_handle_t fh) 305 { 306 307 return (fh->fh_size); 308 } 309 310 /* 311 * firmware_read: 312 * 313 * Read data from a firmware image at the specified offset into 314 * the provided buffer. 315 */ 316 int 317 firmware_read(firmware_handle_t fh, off_t offset, void *buf, size_t len) 318 { 319 320 return (vn_rdwr(UIO_READ, fh->fh_vp, buf, len, offset, 321 UIO_SYSSPACE, 0, kauth_cred_get(), NULL, curlwp)); 322 } 323 324 /* 325 * firmware_malloc: 326 * 327 * Allocate a firmware buffer of the specified size. 328 * 329 * NOTE: This routine may block. 330 */ 331 void * 332 firmware_malloc(size_t size) 333 { 334 335 return (kmem_alloc(size, KM_SLEEP)); 336 } 337 338 /* 339 * firmware_free: 340 * 341 * Free a previously allocated firmware buffer. 342 */ 343 /*ARGSUSED*/ 344 void 345 firmware_free(void *v, size_t size) 346 { 347 348 kmem_free(v, size); 349 } 350