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 "libefivar_int.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 48 { 49 const char *uuid_str; 50 const char *name; 51 efi_guid_t guid; 52 } guid_tbl [] = 53 { 54 { "00000000-0000-0000-0000-000000000000", "zero", Z }, 55 { "093e0fae-a6c4-4f50-9f1b-d41e2b89c19a", "sha512", Z }, 56 { "0abba7dc-e516-4167-bbf5-4d9d1c739416", "redhat", Z }, 57 { "0b6e5233-a65c-44c9-9407-d9ab83bfc8bd", "sha224", Z }, 58 { "126a762d-5758-4fca-8531-201a7f57f850", "lenovo_boot_menu", Z }, 59 { "3bd2a492-96c0-4079-b420-fcf98ef103ed", "x509_sha256", Z }, 60 { "3c5766e8-269c-4e34-aa14-ed776e85b3b6", "rsa2048", Z }, 61 { "3CC24E96-22C7-41D8-8863-8E39DCDCC2CF", "lenovo", Z }, 62 { "3f7e615b-0d45-4f80-88dc-26b234958560", "lenovo_diag", Z }, 63 { "446dbf63-2502-4cda-bcfa-2465d2b0fe9d", "x509_sha512", Z }, 64 { "4aafd29d-68df-49ee-8aa9-347d375665a7", "pkcs7_cert", Z }, 65 { "605dab50-e046-4300-abb6-3dd810dd8b23", "shim", Z }, 66 { "665d3f60-ad3e-4cad-8e26-db46eee9f1b5", "lenovo_rescue", Z }, 67 { "67f8444f-8743-48f1-a328-1eaab8736080", "rsa2048_sha1", Z }, 68 { "7076876e-80c2-4ee6-aad2-28b349a6865b", "x509_sha384", Z }, 69 { "721c8b66-426c-4e86-8e99-3457c46ab0b9", "lenovo_setup", Z }, 70 { "77fa9abd-0359-4d32-bd60-28f4e78f784b", "microsoft", Z }, 71 { "7FACC7B6-127F-4E9C-9C5D-080F98994345", "lenovo_2", Z }, 72 { "826ca512-cf10-4ac9-b187-be01496631bd", "sha1", Z }, 73 { "82988420-7467-4490-9059-feb448dd1963", "lenovo_me_config", Z }, 74 { "8be4df61-93ca-11d2-aa0d-00e098032b8c", "global", Z }, 75 { "a5c059a1-94e4-4aa7-87b5-ab155c2bf072", "x509_cert", Z }, 76 { "a7717414-c616-4977-9420-844712a735bf", "rsa2048_sha256_cert", Z }, 77 { "a7d8d9a6-6ab0-4aeb-ad9d-163e59a7a380", "lenovo_diag_splash", Z }, 78 { "ade9e48f-9cb8-98e6-31af-b4e6009e2fe3", "redhat_2", Z }, 79 { "bc7838d2-0f82-4d60-8316-c068ee79d25b", "lenovo_msg", Z }, 80 { "c1c41626-504c-4092-aca9-41f936934328", "sha256", Z }, 81 { "c57ad6b7-0515-40a8-9d21-551652854e37", "shell", Z }, 82 { "d719b2cb-3d3a-4596-a3bc-dad00e67656f", "security", Z }, 83 { "e2b36190-879b-4a3d-ad8d-f2e7bba32784", "rsa2048_sha256", Z }, 84 { "ff3e5307-9fd0-48c9-85f1-8ad56c701e01", "sha384", Z }, 85 { "f46ee6f4-4785-43a3-923d-7f786c3c8479", "lenovo_startup_interrupt", Z }, 86 { "ffffffff-ffff-ffff-ffff-ffffffffffff", "zzignore-this-guid", Z }, 87 }; 88 #undef Z 89 90 static void 91 efi_guid_tbl_compile(void) 92 { 93 size_t i; 94 uint32_t status; 95 96 for (i = 0; i < nitems(guid_tbl); i++) { 97 uuid_from_string(guid_tbl[i].uuid_str, &guid_tbl[i].guid, 98 &status); 99 /* all f's is a bad version, so ignore that error */ 100 if (status != uuid_s_ok && status != uuid_s_bad_version) 101 fprintf(stderr, "Can't convert %s to a uuid for %s: %d\n", 102 guid_tbl[i].uuid_str, guid_tbl[i].name, (int)status); 103 } 104 } 105 106 static int 107 efi_open_dev(void) 108 { 109 110 if (efi_fd == -2) 111 efi_fd = open("/dev/efi", O_RDWR); 112 if (efi_fd < 0) 113 efi_fd = -1; 114 else 115 efi_guid_tbl_compile(); 116 return (efi_fd); 117 } 118 119 static void 120 efi_var_reset(struct efi_var_ioc *var) 121 { 122 var->name = NULL; 123 var->namesize = 0; 124 memset(&var->vendor, 0, sizeof(var->vendor)); 125 var->attrib = 0; 126 var->data = NULL; 127 var->datasize = 0; 128 } 129 130 static int 131 rv_to_linux_rv(int rv) 132 { 133 if (rv == 0) 134 rv = 1; 135 else 136 rv = -errno; 137 return (rv); 138 } 139 140 int 141 efi_append_variable(efi_guid_t guid, const char *name, 142 uint8_t *data, size_t data_size, uint32_t attributes) 143 { 144 145 return efi_set_variable(guid, name, data, data_size, 146 attributes | EFI_VARIABLE_APPEND_WRITE, 0); 147 } 148 149 int 150 efi_del_variable(efi_guid_t guid, const char *name) 151 { 152 153 /* data_size of 0 deletes the variable */ 154 return efi_set_variable(guid, name, NULL, 0, 0, 0); 155 } 156 157 int 158 efi_get_variable(efi_guid_t guid, const char *name, 159 uint8_t **data, size_t *data_size, uint32_t *attributes) 160 { 161 struct efi_var_ioc var; 162 int rv; 163 static uint8_t buf[1024*32]; 164 165 if (efi_open_dev() == -1) 166 return -1; 167 168 efi_var_reset(&var); 169 rv = libefi_utf8_to_ucs2(name, &var.name, &var.namesize); 170 if (rv != 0) 171 goto errout; 172 var.vendor = guid; 173 var.data = buf; 174 var.datasize = sizeof(buf); 175 rv = ioctl(efi_fd, EFIIOC_VAR_GET, &var); 176 if (data_size != NULL) 177 *data_size = var.datasize; 178 if (data != NULL) 179 *data = buf; 180 if (attributes != NULL) 181 *attributes = var.attrib; 182 errout: 183 free(var.name); 184 185 return rv_to_linux_rv(rv); 186 } 187 188 int 189 efi_get_variable_attributes(efi_guid_t guid, const char *name, 190 uint32_t *attributes) 191 { 192 /* Make sure this construct works -- I think it will fail */ 193 194 return efi_get_variable(guid, name, NULL, NULL, attributes); 195 } 196 197 int 198 efi_get_variable_size(efi_guid_t guid, const char *name, 199 size_t *size) 200 { 201 202 /* XXX check to make sure this matches the linux value */ 203 204 *size = 0; 205 return efi_get_variable(guid, name, NULL, size, NULL); 206 } 207 208 int 209 efi_get_next_variable_name(efi_guid_t **guid, char **name) 210 { 211 struct efi_var_ioc var; 212 int rv; 213 static efi_char *buf; 214 static size_t buflen = 256 * sizeof(efi_char); 215 static efi_guid_t retguid; 216 size_t size; 217 218 if (efi_open_dev() == -1) 219 return -1; 220 221 if (buf == NULL) 222 buf = malloc(buflen); 223 224 again: 225 efi_var_reset(&var); 226 var.name = buf; 227 var.namesize = buflen; 228 if (*name == NULL) { 229 *buf = 0; 230 /* GUID zeroed in var_reset */ 231 } else { 232 rv = libefi_utf8_to_ucs2(*name, &var.name, &size); 233 if (rv != 0) 234 goto errout; 235 var.vendor = **guid; 236 } 237 rv = ioctl(efi_fd, EFIIOC_VAR_NEXT, &var); 238 if (rv == 0 && var.name == NULL) { 239 /* 240 * oops, too little space. Try again. 241 */ 242 void *new = realloc(buf, buflen); 243 buflen = var.namesize; 244 if (new == NULL) { 245 rv = -1; 246 errno = ENOMEM; 247 goto done; 248 } 249 buf = new; 250 goto again; 251 } 252 253 if (rv == 0) { 254 *name = NULL; /* XXX */ 255 var.name[var.namesize / sizeof(efi_char)] = 0; /* EFI doesn't NUL terminate */ 256 rv = libefi_ucs2_to_utf8(var.name, name); 257 if (rv != 0) 258 goto errout; 259 retguid = var.vendor; 260 *guid = &retguid; 261 } 262 errout: 263 264 /* XXX The linux interface expects name to be a static buffer -- fix or leak memory? */ 265 done: 266 if (errno == ENOENT) { 267 errno = 0; 268 return 0; 269 } 270 271 return (rv_to_linux_rv(rv)); 272 } 273 274 int 275 efi_guid_cmp(const efi_guid_t *guid1, const efi_guid_t *guid2) 276 { 277 uint32_t status; 278 279 return uuid_compare(guid1, guid2, &status); 280 } 281 282 int 283 efi_guid_is_zero(const efi_guid_t *guid) 284 { 285 uint32_t status; 286 287 return uuid_is_nil(guid, &status); 288 } 289 290 int 291 efi_guid_to_name(efi_guid_t *guid, char **name) 292 { 293 size_t i; 294 uint32_t status; 295 296 for (i = 0; i < nitems(guid_tbl); i++) { 297 if (uuid_equal(guid, &guid_tbl[i].guid, &status)) { 298 *name = strdup(guid_tbl[i].name); 299 return (0); 300 } 301 } 302 return (efi_guid_to_str(guid, name)); 303 } 304 305 int 306 efi_guid_to_symbol(efi_guid_t *guid __unused, char **symbol __unused) 307 { 308 309 /* 310 * Unsure what this is used for, efibootmgr doesn't use it. 311 * Leave unimplemented for now. 312 */ 313 return -1; 314 } 315 316 int 317 efi_guid_to_str(const efi_guid_t *guid, char **sp) 318 { 319 uint32_t status; 320 321 /* knows efi_guid_t is a typedef of uuid_t */ 322 uuid_to_string(guid, sp, &status); 323 324 return (status == uuid_s_ok ? 0 : -1); 325 } 326 327 int 328 efi_name_to_guid(const char *name, efi_guid_t *guid) 329 { 330 size_t i; 331 332 for (i = 0; i < nitems(guid_tbl); i++) { 333 if (strcmp(name, guid_tbl[i].name) == 0) { 334 *guid = guid_tbl[i].guid; 335 return (0); 336 } 337 } 338 return (efi_str_to_guid(name, guid)); 339 } 340 341 int 342 efi_set_variable(efi_guid_t guid, const char *name, 343 uint8_t *data, size_t data_size, uint32_t attributes, mode_t mode __unused) 344 { 345 struct efi_var_ioc var; 346 int rv; 347 348 if (efi_open_dev() == -1) 349 return -1; 350 351 efi_var_reset(&var); 352 rv = libefi_utf8_to_ucs2(name, &var.name, &var.namesize); 353 if (rv != 0) 354 goto errout; 355 var.vendor = guid; 356 var.data = data; 357 var.datasize = data_size; 358 var.attrib = attributes; 359 rv = ioctl(efi_fd, EFIIOC_VAR_SET, &var); 360 errout: 361 free(var.name); 362 363 return rv; 364 } 365 366 int 367 efi_str_to_guid(const char *s, efi_guid_t *guid) 368 { 369 uint32_t status; 370 371 /* knows efi_guid_t is a typedef of uuid_t */ 372 uuid_from_string(s, guid, &status); 373 374 return (status == uuid_s_ok ? 0 : -1); 375 } 376 377 int 378 efi_variables_supported(void) 379 { 380 381 return efi_open_dev() != -1; 382 } 383