1 /* $NetBSD: firmload.c,v 1.22 2016/05/30 02:33:49 dholland 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 1.22 2016/05/30 02:33:49 dholland 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 != '/') { /* empty or not absolute */ 146 *prefixp = NULL; 147 return (NULL); 148 } 149 150 /* 151 * Compute the max path prefix based on the length of the provided 152 * names. 153 */ 154 maxprefix = MAXPATHLEN - 155 (1 /* / */ 156 + strlen(drvname) 157 + 1 /* / */ 158 + strlen(imgname) 159 + 1 /* terminating NUL */); 160 161 /* Check for underflow (size_t is unsigned). */ 162 if (maxprefix > MAXPATHLEN) { 163 *prefixp = NULL; 164 return (NULL); 165 } 166 167 for (i = 0; i < maxprefix; i++) { 168 if (*prefix == ':' || *prefix == '\0') 169 break; 170 pnbuf[i] = *prefix++; 171 } 172 173 if (*prefix != ':' && *prefix != '\0') { 174 /* Path prefix was too long. */ 175 *prefixp = NULL; 176 return (NULL); 177 } 178 179 if (*prefix != '\0') 180 prefix++; 181 *prefixp = prefix; 182 183 KASSERT(MAXPATHLEN >= i); 184 snprintf(pnbuf + i, MAXPATHLEN - i, "/%s/%s", drvname, imgname); 185 186 return (pnbuf); 187 } 188 189 static char * 190 firmware_path_first(const char *drvname, const char *imgname, char *pnbuf, 191 char **prefixp) 192 { 193 194 *prefixp = firmware_paths; 195 return (firmware_path_next(drvname, imgname, pnbuf, prefixp)); 196 } 197 198 /* 199 * firmware_open: 200 * 201 * Open a firmware image and return its handle. 202 */ 203 int 204 firmware_open(const char *drvname, const char *imgname, firmware_handle_t *fhp) 205 { 206 struct pathbuf *pb; 207 struct nameidata nd; 208 struct vattr va; 209 char *pnbuf, *path, *prefix; 210 firmware_handle_t fh; 211 struct vnode *vp; 212 int error; 213 extern struct cwdinfo cwdi0; 214 215 if (drvname == NULL || imgname == NULL) 216 return (EINVAL); 217 218 if (cwdi0.cwdi_cdir == NULL) { 219 printf("firmware_open(%s/%s) called too early.\n", 220 drvname, imgname); 221 return ENOENT; 222 } 223 224 pnbuf = PNBUF_GET(); 225 KASSERT(pnbuf != NULL); 226 227 fh = firmware_handle_alloc(); 228 KASSERT(fh != NULL); 229 230 error = 0; 231 for (path = firmware_path_first(drvname, imgname, pnbuf, &prefix); 232 path != NULL; 233 path = firmware_path_next(drvname, imgname, pnbuf, &prefix)) { 234 pb = pathbuf_create(path); 235 if (pb == NULL) { 236 error = ENOMEM; 237 break; 238 } 239 NDINIT(&nd, LOOKUP, FOLLOW | NOCHROOT, pb); 240 error = vn_open(&nd, FREAD, 0); 241 pathbuf_destroy(pb); 242 if (error == ENOENT) { 243 continue; 244 } 245 break; 246 } 247 248 PNBUF_PUT(pnbuf); 249 if (error) { 250 firmware_handle_free(fh); 251 return (error); 252 } 253 254 vp = nd.ni_vp; 255 256 error = VOP_GETATTR(vp, &va, kauth_cred_get()); 257 if (error) { 258 VOP_UNLOCK(vp); 259 (void)vn_close(vp, FREAD, kauth_cred_get()); 260 firmware_handle_free(fh); 261 return (error); 262 } 263 264 if (va.va_type != VREG) { 265 VOP_UNLOCK(vp); 266 (void)vn_close(vp, FREAD, kauth_cred_get()); 267 firmware_handle_free(fh); 268 return (EINVAL); 269 } 270 271 /* XXX Mark as busy text file. */ 272 273 fh->fh_vp = vp; 274 fh->fh_size = va.va_size; 275 276 VOP_UNLOCK(vp); 277 278 *fhp = fh; 279 return (0); 280 } 281 282 /* 283 * firmware_close: 284 * 285 * Close a firmware image. 286 */ 287 int 288 firmware_close(firmware_handle_t fh) 289 { 290 int error; 291 292 error = vn_close(fh->fh_vp, FREAD, kauth_cred_get()); 293 firmware_handle_free(fh); 294 return (error); 295 } 296 297 /* 298 * firmware_get_size: 299 * 300 * Return the total size of a firmware image. 301 */ 302 off_t 303 firmware_get_size(firmware_handle_t fh) 304 { 305 306 return (fh->fh_size); 307 } 308 309 /* 310 * firmware_read: 311 * 312 * Read data from a firmware image at the specified offset into 313 * the provided buffer. 314 */ 315 int 316 firmware_read(firmware_handle_t fh, off_t offset, void *buf, size_t len) 317 { 318 319 return (vn_rdwr(UIO_READ, fh->fh_vp, buf, len, offset, 320 UIO_SYSSPACE, 0, kauth_cred_get(), NULL, curlwp)); 321 } 322 323 /* 324 * firmware_malloc: 325 * 326 * Allocate a firmware buffer of the specified size. 327 * 328 * NOTE: This routine may block. 329 */ 330 void * 331 firmware_malloc(size_t size) 332 { 333 334 return (kmem_alloc(size, KM_SLEEP)); 335 } 336 337 /* 338 * firmware_free: 339 * 340 * Free a previously allocated firmware buffer. 341 */ 342 /*ARGSUSED*/ 343 void 344 firmware_free(void *v, size_t size) 345 { 346 347 kmem_free(v, size); 348 } 349