1 /*- 2 * Copyright (c) 2016 Netflix, Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer 10 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <efivar.h> 31 #include <sys/efiio.h> 32 #include <sys/param.h> 33 #include <errno.h> 34 #include <fcntl.h> 35 #include <stdio.h> 36 #include <stdlib.h> 37 #include <string.h> 38 39 #include "efichar.h" 40 41 static int efi_fd = -2; 42 43 #define Z { 0, 0, 0, 0, 0, { 0 } } 44 45 const efi_guid_t efi_guid_empty = Z; 46 47 static struct uuid_table guid_tbl [] = 48 { 49 { "00000000-0000-0000-0000-000000000000", "zero", Z }, 50 { "093e0fae-a6c4-4f50-9f1b-d41e2b89c19a", "sha512", Z }, 51 { "0abba7dc-e516-4167-bbf5-4d9d1c739416", "redhat", Z }, 52 { "0b6e5233-a65c-44c9-9407-d9ab83bfc8bd", "sha224", Z }, 53 { "126a762d-5758-4fca-8531-201a7f57f850", "lenovo_boot_menu", Z }, 54 { "3bd2a492-96c0-4079-b420-fcf98ef103ed", "x509_sha256", Z }, 55 { "3c5766e8-269c-4e34-aa14-ed776e85b3b6", "rsa2048", Z }, 56 { "3CC24E96-22C7-41D8-8863-8E39DCDCC2CF", "lenovo", Z }, 57 { "3f7e615b-0d45-4f80-88dc-26b234958560", "lenovo_diag", Z }, 58 { "446dbf63-2502-4cda-bcfa-2465d2b0fe9d", "x509_sha512", Z }, 59 { "4aafd29d-68df-49ee-8aa9-347d375665a7", "pkcs7_cert", Z }, 60 { "605dab50-e046-4300-abb6-3dd810dd8b23", "shim", Z }, 61 { "665d3f60-ad3e-4cad-8e26-db46eee9f1b5", "lenovo_rescue", Z }, 62 { "67f8444f-8743-48f1-a328-1eaab8736080", "rsa2048_sha1", Z }, 63 { "7076876e-80c2-4ee6-aad2-28b349a6865b", "x509_sha384", Z }, 64 { "721c8b66-426c-4e86-8e99-3457c46ab0b9", "lenovo_setup", Z }, 65 { "77fa9abd-0359-4d32-bd60-28f4e78f784b", "microsoft", Z }, 66 { "7FACC7B6-127F-4E9C-9C5D-080F98994345", "lenovo_2", Z }, 67 { "826ca512-cf10-4ac9-b187-be01496631bd", "sha1", Z }, 68 { "82988420-7467-4490-9059-feb448dd1963", "lenovo_me_config", Z }, 69 { "8be4df61-93ca-11d2-aa0d-00e098032b8c", "global", Z }, 70 { "a5c059a1-94e4-4aa7-87b5-ab155c2bf072", "x509_cert", Z }, 71 { "a7717414-c616-4977-9420-844712a735bf", "rsa2048_sha256_cert", Z }, 72 { "a7d8d9a6-6ab0-4aeb-ad9d-163e59a7a380", "lenovo_diag_splash", Z }, 73 { "ade9e48f-9cb8-98e6-31af-b4e6009e2fe3", "redhat_2", Z }, 74 { "bc7838d2-0f82-4d60-8316-c068ee79d25b", "lenovo_msg", Z }, 75 { "c1c41626-504c-4092-aca9-41f936934328", "sha256", Z }, 76 { "c57ad6b7-0515-40a8-9d21-551652854e37", "shell", Z }, 77 { "d719b2cb-3d3a-4596-a3bc-dad00e67656f", "security", Z }, 78 { "e2b36190-879b-4a3d-ad8d-f2e7bba32784", "rsa2048_sha256", Z }, 79 { "ff3e5307-9fd0-48c9-85f1-8ad56c701e01", "sha384", Z }, 80 { "f46ee6f4-4785-43a3-923d-7f786c3c8479", "lenovo_startup_interrupt", Z }, 81 { "ffffffff-ffff-ffff-ffff-ffffffffffff", "zzignore-this-guid", Z }, 82 }; 83 #undef Z 84 85 static void 86 efi_guid_tbl_compile(void) 87 { 88 size_t i; 89 uint32_t status; 90 static int done = 0; 91 92 if (done) 93 return; 94 for (i = 0; i < nitems(guid_tbl); i++) { 95 uuid_from_string(guid_tbl[i].uuid_str, &guid_tbl[i].guid, 96 &status); 97 /* all f's is a bad version, so ignore that error */ 98 if (status != uuid_s_ok && status != uuid_s_bad_version) 99 fprintf(stderr, "Can't convert %s to a uuid for %s: %d\n", 100 guid_tbl[i].uuid_str, guid_tbl[i].name, (int)status); 101 } 102 done = 1; 103 } 104 105 int 106 efi_known_guid(struct uuid_table **tbl) 107 { 108 109 *tbl = guid_tbl; 110 return (nitems(guid_tbl)); 111 } 112 113 static int 114 efi_open_dev(void) 115 { 116 117 if (efi_fd == -2) 118 efi_fd = open("/dev/efi", O_RDWR); 119 if (efi_fd < 0) 120 efi_fd = -1; 121 else 122 efi_guid_tbl_compile(); 123 return (efi_fd); 124 } 125 126 static void 127 efi_var_reset(struct efi_var_ioc *var) 128 { 129 var->name = NULL; 130 var->namesize = 0; 131 memset(&var->vendor, 0, sizeof(var->vendor)); 132 var->attrib = 0; 133 var->data = NULL; 134 var->datasize = 0; 135 } 136 137 static int 138 rv_to_linux_rv(int rv) 139 { 140 if (rv == 0) 141 rv = 1; 142 else 143 rv = -errno; 144 return (rv); 145 } 146 147 int 148 efi_append_variable(efi_guid_t guid, const char *name, 149 uint8_t *data, size_t data_size, uint32_t attributes) 150 { 151 152 return efi_set_variable(guid, name, data, data_size, 153 attributes | EFI_VARIABLE_APPEND_WRITE); 154 } 155 156 int 157 efi_del_variable(efi_guid_t guid, const char *name) 158 { 159 160 /* data_size of 0 deletes the variable */ 161 return efi_set_variable(guid, name, NULL, 0, 0); 162 } 163 164 int 165 efi_get_variable(efi_guid_t guid, const char *name, 166 uint8_t **data, size_t *data_size, uint32_t *attributes) 167 { 168 struct efi_var_ioc var; 169 int rv; 170 static uint8_t buf[1024*32]; 171 172 if (efi_open_dev() == -1) 173 return -1; 174 175 efi_var_reset(&var); 176 rv = utf8_to_ucs2(name, &var.name, &var.namesize); 177 if (rv != 0) 178 goto errout; 179 var.vendor = guid; 180 var.data = buf; 181 var.datasize = sizeof(buf); 182 rv = ioctl(efi_fd, EFIIOC_VAR_GET, &var); 183 if (data_size != NULL) 184 *data_size = var.datasize; 185 if (data != NULL) 186 *data = buf; 187 if (attributes != NULL) 188 *attributes = var.attrib; 189 errout: 190 free(var.name); 191 192 return rv_to_linux_rv(rv); 193 } 194 195 int 196 efi_get_variable_attributes(efi_guid_t guid, const char *name, 197 uint32_t *attributes) 198 { 199 /* Make sure this construct works -- I think it will fail */ 200 201 return efi_get_variable(guid, name, NULL, NULL, attributes); 202 } 203 204 int 205 efi_get_variable_size(efi_guid_t guid, const char *name, 206 size_t *size) 207 { 208 209 /* XXX check to make sure this matches the linux value */ 210 211 *size = 0; 212 return efi_get_variable(guid, name, NULL, size, NULL); 213 } 214 215 int 216 efi_get_next_variable_name(efi_guid_t **guid, char **name) 217 { 218 struct efi_var_ioc var; 219 int rv; 220 static efi_char *buf; 221 static size_t buflen = 256 * sizeof(efi_char); 222 static efi_guid_t retguid; 223 size_t size; 224 225 if (efi_open_dev() == -1) 226 return -1; 227 228 /* 229 * Always allocate enough for an extra NUL on the end, but don't tell 230 * the IOCTL about it so we can NUL terminate the name before converting 231 * it to UTF8. 232 */ 233 if (buf == NULL) 234 buf = malloc(buflen + sizeof(efi_char)); 235 236 again: 237 efi_var_reset(&var); 238 var.name = buf; 239 var.namesize = buflen; 240 if (*name == NULL) { 241 *buf = 0; 242 /* GUID zeroed in var_reset */ 243 } else { 244 rv = utf8_to_ucs2(*name, &var.name, &size); 245 if (rv != 0) 246 goto errout; 247 var.vendor = **guid; 248 } 249 rv = ioctl(efi_fd, EFIIOC_VAR_NEXT, &var); 250 if (rv == 0 && var.name == NULL) { 251 /* 252 * Variable name not long enough, so allocate more space for the 253 * name and try again. As above, mind the NUL we add. 254 */ 255 void *new = realloc(buf, var.namesize + sizeof(efi_char)); 256 if (new == NULL) { 257 rv = -1; 258 errno = ENOMEM; 259 goto done; 260 } 261 buflen = var.namesize; 262 buf = new; 263 goto again; 264 } 265 266 if (rv == 0) { 267 free(*name); /* Free last name, to avoid leaking */ 268 *name = NULL; /* Force ucs2_to_utf8 to malloc new space */ 269 var.name[var.namesize / sizeof(efi_char)] = 0; /* EFI doesn't NUL terminate */ 270 rv = ucs2_to_utf8(var.name, name); 271 if (rv != 0) 272 goto errout; 273 retguid = var.vendor; 274 *guid = &retguid; 275 } 276 errout: 277 278 /* XXX The linux interface expects name to be a static buffer -- fix or leak memory? */ 279 /* XXX for the moment, we free just before we'd leak, but still leak last one */ 280 done: 281 if (rv != 0 && errno == ENOENT) { 282 errno = 0; 283 free(*name); /* Free last name, to avoid leaking */ 284 return 0; 285 } 286 287 return (rv_to_linux_rv(rv)); 288 } 289 290 int 291 efi_guid_cmp(const efi_guid_t *guid1, const efi_guid_t *guid2) 292 { 293 uint32_t status; 294 295 return uuid_compare(guid1, guid2, &status); 296 } 297 298 int 299 efi_guid_is_zero(const efi_guid_t *guid) 300 { 301 uint32_t status; 302 303 return uuid_is_nil(guid, &status); 304 } 305 306 int 307 efi_guid_to_name(efi_guid_t *guid, char **name) 308 { 309 size_t i; 310 uint32_t status; 311 312 efi_guid_tbl_compile(); 313 for (i = 0; i < nitems(guid_tbl); i++) { 314 if (uuid_equal(guid, &guid_tbl[i].guid, &status)) { 315 *name = strdup(guid_tbl[i].name); 316 return (0); 317 } 318 } 319 return (efi_guid_to_str(guid, name)); 320 } 321 322 int 323 efi_guid_to_symbol(efi_guid_t *guid __unused, char **symbol __unused) 324 { 325 326 /* 327 * Unsure what this is used for, efibootmgr doesn't use it. 328 * Leave unimplemented for now. 329 */ 330 return -1; 331 } 332 333 int 334 efi_guid_to_str(const efi_guid_t *guid, char **sp) 335 { 336 uint32_t status; 337 338 /* knows efi_guid_t is a typedef of uuid_t */ 339 uuid_to_string(guid, sp, &status); 340 341 return (status == uuid_s_ok ? 0 : -1); 342 } 343 344 int 345 efi_name_to_guid(const char *name, efi_guid_t *guid) 346 { 347 size_t i; 348 349 efi_guid_tbl_compile(); 350 for (i = 0; i < nitems(guid_tbl); i++) { 351 if (strcmp(name, guid_tbl[i].name) == 0) { 352 *guid = guid_tbl[i].guid; 353 return (0); 354 } 355 } 356 return (efi_str_to_guid(name, guid)); 357 } 358 359 int 360 efi_set_variable(efi_guid_t guid, const char *name, 361 uint8_t *data, size_t data_size, uint32_t attributes) 362 { 363 struct efi_var_ioc var; 364 int rv; 365 366 if (efi_open_dev() == -1) 367 return -1; 368 369 efi_var_reset(&var); 370 rv = utf8_to_ucs2(name, &var.name, &var.namesize); 371 if (rv != 0) 372 goto errout; 373 var.vendor = guid; 374 var.data = data; 375 var.datasize = data_size; 376 var.attrib = attributes; 377 rv = ioctl(efi_fd, EFIIOC_VAR_SET, &var); 378 errout: 379 free(var.name); 380 381 return rv; 382 } 383 384 int 385 efi_str_to_guid(const char *s, efi_guid_t *guid) 386 { 387 uint32_t status; 388 389 /* knows efi_guid_t is a typedef of uuid_t */ 390 uuid_from_string(s, guid, &status); 391 392 return (status == uuid_s_ok ? 0 : -1); 393 } 394 395 int 396 efi_variables_supported(void) 397 { 398 399 return efi_open_dev() != -1; 400 } 401