| 1 | /* |
| 2 | * SPDX-License-Identifier: GPL-2.0-or-later |
| 3 | * |
| 4 | * uefi vars device - EfiSmmVariableProtocol implementation |
| 5 | */ |
| 6 | #include "qemu/osdep.h" |
| 7 | #include "qemu/error-report.h" |
| 8 | #include "system/dma.h" |
| 9 | #include "migration/vmstate.h" |
| 10 | |
| 11 | #include "hw/uefi/var-service.h" |
| 12 | #include "hw/uefi/var-service-api.h" |
| 13 | #include "hw/uefi/var-service-edk2.h" |
| 14 | |
| 15 | #include "trace.h" |
| 16 | |
| 17 | #define EFI_VARIABLE_ATTRIBUTE_SUPPORTED \ |
| 18 | (EFI_VARIABLE_NON_VOLATILE | \ |
| 19 | EFI_VARIABLE_BOOTSERVICE_ACCESS | \ |
| 20 | EFI_VARIABLE_RUNTIME_ACCESS | \ |
| 21 | EFI_VARIABLE_HARDWARE_ERROR_RECORD | \ |
| 22 | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS | \ |
| 23 | EFI_VARIABLE_APPEND_WRITE) |
| 24 | |
| 25 | |
| 26 | const VMStateDescription vmstate_uefi_time = { |
| 27 | .name = "uefi-time", |
| 28 | .fields = (VMStateField[]) { |
| 29 | VMSTATE_UINT16(year, efi_time), |
| 30 | VMSTATE_UINT8(month, efi_time), |
| 31 | VMSTATE_UINT8(day, efi_time), |
| 32 | VMSTATE_UINT8(hour, efi_time), |
| 33 | VMSTATE_UINT8(minute, efi_time), |
| 34 | VMSTATE_UINT8(second, efi_time), |
| 35 | VMSTATE_UINT32(nanosecond, efi_time), |
| 36 | VMSTATE_END_OF_LIST() |
| 37 | }, |
| 38 | }; |
| 39 | |
| 40 | static int uefi_vars_pre_load(void *opaque) |
| 41 | { |
| 42 | uefi_variable *var = opaque; |
| 43 | |
| 44 | /* clear digest which is optional in the live migration data stream */ |
| 45 | var->digest = NULL; |
| 46 | var->digest_size = 0; |
| 47 | return 0; |
| 48 | } |
| 49 | |
| 50 | static int uefi_vars_post_load(void *opaque, int version_id) |
| 51 | { |
| 52 | uefi_variable *var = opaque; |
| 53 | |
| 54 | if (!uefi_str_is_valid(var->name, var->name_size, true) || |
| 55 | var->attributes & ~EFI_VARIABLE_ATTRIBUTE_SUPPORTED || |
| 56 | (var->digest_size != 0 && |
| 57 | var->digest_size != 32 /* AUTHVAR_DIGEST_SIZE */)) { |
| 58 | error_report("invalid uefi variable"); |
| 59 | return -1; |
| 60 | } |
| 61 | return 0; |
| 62 | } |
| 63 | |
| 64 | static bool uefi_vars_digest_is_needed(void *opaque) |
| 65 | { |
| 66 | uefi_variable *var = opaque; |
| 67 | |
| 68 | if ((var->attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) |
| 69 | && !uefi_vars_is_sb_any(var)) { |
| 70 | return true; |
| 71 | } |
| 72 | return false; |
| 73 | } |
| 74 | |
| 75 | const VMStateDescription vmstate_uefi_variable_digest = { |
| 76 | .name = "uefi-variable-digest", |
| 77 | .needed = uefi_vars_digest_is_needed, |
| 78 | .fields = (VMStateField[]) { |
| 79 | VMSTATE_UINT32(digest_size, uefi_variable), |
| 80 | VMSTATE_VBUFFER_ALLOC_UINT32(digest, uefi_variable, |
| 81 | 0, NULL, digest_size), |
| 82 | VMSTATE_END_OF_LIST() |
| 83 | }, |
| 84 | }; |
| 85 | |
| 86 | const VMStateDescription vmstate_uefi_variable = { |
| 87 | .name = "uefi-variable", |
| 88 | .pre_load = uefi_vars_pre_load, |
| 89 | .post_load = uefi_vars_post_load, |
| 90 | .fields = (VMStateField[]) { |
| 91 | VMSTATE_UINT8_ARRAY_V(guid.data, uefi_variable, sizeof(QemuUUID), 0), |
| 92 | VMSTATE_UINT32(name_size, uefi_variable), |
| 93 | VMSTATE_UINT32(data_size, uefi_variable), |
| 94 | VMSTATE_UINT32(attributes, uefi_variable), |
| 95 | VMSTATE_VBUFFER_ALLOC_UINT32(name, uefi_variable, 0, NULL, name_size), |
| 96 | VMSTATE_VBUFFER_ALLOC_UINT32(data, uefi_variable, 0, NULL, data_size), |
| 97 | VMSTATE_STRUCT(time, uefi_variable, 0, vmstate_uefi_time, efi_time), |
| 98 | VMSTATE_END_OF_LIST() |
| 99 | }, |
| 100 | .subsections = (const VMStateDescription * const []) { |
| 101 | &vmstate_uefi_variable_digest, |
| 102 | NULL |
| 103 | } |
| 104 | }; |
| 105 | |
| 106 | uefi_variable *uefi_vars_find_variable(uefi_vars_state *uv, QemuUUID guid, |
| 107 | const uint16_t *name, uint64_t name_size) |
| 108 | { |
| 109 | uefi_variable *var; |
| 110 | |
| 111 | QTAILQ_FOREACH(var, &uv->variables, next) { |
| 112 | if (!uefi_str_equal(var->name, var->name_size, |
| 113 | name, name_size)) { |
| 114 | continue; |
| 115 | } |
| 116 | if (!qemu_uuid_is_equal(&var->guid, &guid)) { |
| 117 | continue; |
| 118 | } |
| 119 | if (!var->data_size) { |
| 120 | /* in process of being created/updated */ |
| 121 | continue; |
| 122 | } |
| 123 | return var; |
| 124 | } |
| 125 | return NULL; |
| 126 | } |
| 127 | |
| 128 | static uefi_variable *add_variable(uefi_vars_state *uv, QemuUUID guid, |
| 129 | const uint16_t *name, uint64_t name_size, |
| 130 | uint32_t attributes) |
| 131 | { |
| 132 | uefi_variable *var; |
| 133 | |
| 134 | var = g_new0(uefi_variable, 1); |
| 135 | var->guid = guid; |
| 136 | var->name = g_malloc(name_size); |
| 137 | memcpy(var->name, name, name_size); |
| 138 | var->name_size = name_size; |
| 139 | var->attributes = attributes; |
| 140 | |
| 141 | var->attributes &= ~EFI_VARIABLE_APPEND_WRITE; |
| 142 | |
| 143 | QTAILQ_INSERT_TAIL(&uv->variables, var, next); |
| 144 | return var; |
| 145 | } |
| 146 | |
| 147 | static void del_variable(uefi_vars_state *uv, uefi_variable *var) |
| 148 | { |
| 149 | if (!var) { |
| 150 | return; |
| 151 | } |
| 152 | |
| 153 | QTAILQ_REMOVE(&uv->variables, var, next); |
| 154 | g_free(var->data); |
| 155 | g_free(var->name); |
| 156 | g_free(var->digest); |
| 157 | g_free(var); |
| 158 | } |
| 159 | |
| 160 | static size_t variable_size(uefi_variable *var) |
| 161 | { |
| 162 | size_t size; |
| 163 | |
| 164 | size = sizeof(*var); |
| 165 | size += var->name_size; |
| 166 | size += var->data_size; |
| 167 | size += var->digest_size; |
| 168 | return size; |
| 169 | } |
| 170 | |
| 171 | void uefi_vars_set_variable(uefi_vars_state *uv, QemuUUID guid, |
| 172 | const uint16_t *name, uint64_t name_size, |
| 173 | uint32_t attributes, |
| 174 | void *data, uint64_t data_size) |
| 175 | { |
| 176 | uefi_variable *old_var, *new_var; |
| 177 | |
| 178 | uefi_trace_variable(__func__, guid, name, name_size); |
| 179 | |
| 180 | old_var = uefi_vars_find_variable(uv, guid, name, name_size); |
| 181 | if (old_var) { |
| 182 | uv->used_storage -= variable_size(old_var); |
| 183 | del_variable(uv, old_var); |
| 184 | } |
| 185 | |
| 186 | new_var = add_variable(uv, guid, name, name_size, attributes); |
| 187 | new_var->data = g_malloc(data_size); |
| 188 | new_var->data_size = data_size; |
| 189 | memcpy(new_var->data, data, data_size); |
| 190 | uv->used_storage += variable_size(new_var); |
| 191 | } |
| 192 | |
| 193 | void uefi_vars_clear_volatile(uefi_vars_state *uv) |
| 194 | { |
| 195 | uefi_variable *var, *n; |
| 196 | |
| 197 | QTAILQ_FOREACH_SAFE(var, &uv->variables, next, n) { |
| 198 | if (var->attributes & EFI_VARIABLE_NON_VOLATILE) { |
| 199 | continue; |
| 200 | } |
| 201 | uv->used_storage -= variable_size(var); |
| 202 | del_variable(uv, var); |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | void uefi_vars_clear_all(uefi_vars_state *uv) |
| 207 | { |
| 208 | uefi_variable *var, *n; |
| 209 | |
| 210 | QTAILQ_FOREACH_SAFE(var, &uv->variables, next, n) { |
| 211 | del_variable(uv, var); |
| 212 | } |
| 213 | uv->used_storage = 0; |
| 214 | } |
| 215 | |
| 216 | void uefi_vars_update_storage(uefi_vars_state *uv) |
| 217 | { |
| 218 | uefi_variable *var; |
| 219 | uefi_var_policy *pol; |
| 220 | |
| 221 | uv->used_storage = 0; |
| 222 | QTAILQ_FOREACH(var, &uv->variables, next) { |
| 223 | uv->used_storage += variable_size(var); |
| 224 | } |
| 225 | QTAILQ_FOREACH(pol, &uv->var_policies, next) { |
| 226 | uv->used_storage += pol->entry->size; |
| 227 | } |
| 228 | } |
| 229 | |
| 230 | static gboolean check_access(uefi_vars_state *uv, uefi_variable *var) |
| 231 | { |
| 232 | if (!uv->exit_boot_service) { |
| 233 | if (!(var->attributes & EFI_VARIABLE_BOOTSERVICE_ACCESS)) { |
| 234 | return false; |
| 235 | } |
| 236 | } else { |
| 237 | if (!(var->attributes & EFI_VARIABLE_RUNTIME_ACCESS)) { |
| 238 | return false; |
| 239 | } |
| 240 | } |
| 241 | return true; |
| 242 | } |
| 243 | |
| 244 | static efi_status check_update(uefi_vars_state *uv, uefi_variable *old_var, |
| 245 | uefi_variable *new_var) |
| 246 | { |
| 247 | efi_status status; |
| 248 | |
| 249 | if (old_var) { |
| 250 | if (!check_access(uv, old_var)) { |
| 251 | return EFI_ACCESS_DENIED; |
| 252 | } |
| 253 | } |
| 254 | |
| 255 | if (new_var) { |
| 256 | if (new_var->attributes & ~EFI_VARIABLE_ATTRIBUTE_SUPPORTED) { |
| 257 | return EFI_UNSUPPORTED; |
| 258 | } |
| 259 | if (!check_access(uv, new_var)) { |
| 260 | return EFI_ACCESS_DENIED; |
| 261 | } |
| 262 | } |
| 263 | |
| 264 | if (old_var && new_var) { |
| 265 | if (old_var->attributes != new_var->attributes) { |
| 266 | return EFI_INVALID_PARAMETER; |
| 267 | } |
| 268 | } |
| 269 | |
| 270 | if (new_var) { |
| 271 | /* create + update */ |
| 272 | status = uefi_vars_policy_check(uv, new_var, old_var == NULL); |
| 273 | } else { |
| 274 | /* delete */ |
| 275 | g_assert(old_var); |
| 276 | status = uefi_vars_policy_check(uv, old_var, false); |
| 277 | } |
| 278 | if (status != EFI_SUCCESS) { |
| 279 | return status; |
| 280 | } |
| 281 | |
| 282 | status = uefi_vars_check_secure_boot(uv, new_var ?: old_var); |
| 283 | if (status != EFI_SUCCESS) { |
| 284 | return status; |
| 285 | } |
| 286 | |
| 287 | return EFI_SUCCESS; |
| 288 | } |
| 289 | |
| 290 | static void append_write(uefi_variable *old_var, |
| 291 | uefi_variable *new_var) |
| 292 | { |
| 293 | uefi_vars_siglist siglist; |
| 294 | uint64_t size; |
| 295 | void *data; |
| 296 | |
| 297 | uefi_vars_siglist_init(&siglist); |
| 298 | uefi_vars_siglist_parse(&siglist, old_var->data, old_var->data_size); |
| 299 | uefi_vars_siglist_parse(&siglist, new_var->data, new_var->data_size); |
| 300 | |
| 301 | size = uefi_vars_siglist_blob_size(&siglist); |
| 302 | data = g_malloc(size); |
| 303 | uefi_vars_siglist_blob_generate(&siglist, data, size); |
| 304 | |
| 305 | g_free(new_var->data); |
| 306 | new_var->data = data; |
| 307 | new_var->data_size = size; |
| 308 | |
| 309 | uefi_vars_siglist_free(&siglist); |
| 310 | } |
| 311 | |
| 312 | static size_t uefi_vars_mm_error(mm_header *mhdr, mm_variable *mvar, |
| 313 | uint64_t status) |
| 314 | { |
| 315 | mvar->status = status; |
| 316 | return sizeof(*mvar); |
| 317 | } |
| 318 | |
| 319 | static bool check_buffer_size(uefi_vars_state *uv, uint64_t length) |
| 320 | { |
| 321 | /* uefi_vars_cmd_mm() checks that */ |
| 322 | g_assert(uv->buf_size >= sizeof(mm_header)); |
| 323 | |
| 324 | if (uv->buf_size - sizeof(mm_header) < length) { |
| 325 | return false; |
| 326 | } |
| 327 | return true; |
| 328 | } |
| 329 | |
| 330 | static size_t uefi_vars_mm_get_variable(uefi_vars_state *uv, mm_header *mhdr, |
| 331 | mm_variable *mvar, void *func) |
| 332 | { |
| 333 | mm_variable_access *va = func; |
| 334 | uint16_t *name; |
| 335 | void *data; |
| 336 | uefi_variable *var; |
| 337 | uint64_t length; |
| 338 | |
| 339 | length = sizeof(*mvar) + sizeof(*va); |
| 340 | if (mhdr->length < length) { |
| 341 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 342 | } |
| 343 | |
| 344 | if (va->name_size > uv->max_storage || |
| 345 | va->data_size > uv->max_storage) { |
| 346 | return uefi_vars_mm_error(mhdr, mvar, EFI_OUT_OF_RESOURCES); |
| 347 | } |
| 348 | |
| 349 | name = func + sizeof(*va); |
| 350 | if (uadd64_overflow(length, va->name_size, &length)) { |
| 351 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 352 | } |
| 353 | if (mhdr->length < length) { |
| 354 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 355 | } |
| 356 | |
| 357 | if (!uefi_str_is_valid(name, va->name_size, true)) { |
| 358 | return uefi_vars_mm_error(mhdr, mvar, EFI_INVALID_PARAMETER); |
| 359 | } |
| 360 | |
| 361 | uefi_trace_variable(__func__, va->guid, name, va->name_size); |
| 362 | |
| 363 | var = uefi_vars_find_variable(uv, va->guid, name, va->name_size); |
| 364 | if (!var) { |
| 365 | return uefi_vars_mm_error(mhdr, mvar, EFI_NOT_FOUND); |
| 366 | } |
| 367 | |
| 368 | /* check permissions etc. */ |
| 369 | if (!check_access(uv, var)) { |
| 370 | return uefi_vars_mm_error(mhdr, mvar, EFI_ACCESS_DENIED); |
| 371 | } |
| 372 | |
| 373 | data = func + sizeof(*va) + va->name_size; |
| 374 | if (uadd64_overflow(length, va->data_size, &length)) { |
| 375 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 376 | } |
| 377 | if (!check_buffer_size(uv, length)) { |
| 378 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 379 | } |
| 380 | |
| 381 | va->attributes = var->attributes; |
| 382 | if (va->data_size < var->data_size) { |
| 383 | va->data_size = var->data_size; |
| 384 | length -= va->data_size; |
| 385 | mvar->status = EFI_BUFFER_TOO_SMALL; |
| 386 | } else { |
| 387 | va->data_size = var->data_size; |
| 388 | memcpy(data, var->data, var->data_size); |
| 389 | mvar->status = EFI_SUCCESS; |
| 390 | } |
| 391 | return length; |
| 392 | } |
| 393 | |
| 394 | static size_t |
| 395 | uefi_vars_mm_get_next_variable(uefi_vars_state *uv, mm_header *mhdr, |
| 396 | mm_variable *mvar, void *func) |
| 397 | { |
| 398 | mm_next_variable *nv = func; |
| 399 | uefi_variable *var; |
| 400 | uint16_t *name; |
| 401 | uint64_t length; |
| 402 | |
| 403 | length = sizeof(*mvar) + sizeof(*nv); |
| 404 | if (mhdr->length < length) { |
| 405 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 406 | } |
| 407 | |
| 408 | if (nv->name_size > uv->max_storage) { |
| 409 | return uefi_vars_mm_error(mhdr, mvar, EFI_OUT_OF_RESOURCES); |
| 410 | } |
| 411 | |
| 412 | name = func + sizeof(*nv); |
| 413 | if (uadd64_overflow(length, nv->name_size, &length)) { |
| 414 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 415 | } |
| 416 | if (mhdr->length < length) { |
| 417 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 418 | } |
| 419 | |
| 420 | if (!uefi_str_is_valid(name, nv->name_size, true)) { |
| 421 | return uefi_vars_mm_error(mhdr, mvar, EFI_INVALID_PARAMETER); |
| 422 | } |
| 423 | |
| 424 | if (uefi_strlen(name, nv->name_size) == 0) { |
| 425 | /* empty string -> first */ |
| 426 | var = QTAILQ_FIRST(&uv->variables); |
| 427 | while (var && !check_access(uv, var)) { |
| 428 | var = QTAILQ_NEXT(var, next); |
| 429 | } |
| 430 | if (!var) { |
| 431 | return uefi_vars_mm_error(mhdr, mvar, EFI_NOT_FOUND); |
| 432 | } |
| 433 | } else { |
| 434 | var = uefi_vars_find_variable(uv, nv->guid, name, nv->name_size); |
| 435 | if (!var) { |
| 436 | return uefi_vars_mm_error(mhdr, mvar, EFI_INVALID_PARAMETER); |
| 437 | } |
| 438 | do { |
| 439 | var = QTAILQ_NEXT(var, next); |
| 440 | } while (var && !check_access(uv, var)); |
| 441 | if (!var) { |
| 442 | return uefi_vars_mm_error(mhdr, mvar, EFI_NOT_FOUND); |
| 443 | } |
| 444 | } |
| 445 | |
| 446 | length = sizeof(*mvar) + sizeof(*nv) + var->name_size; |
| 447 | if (!check_buffer_size(uv, length)) { |
| 448 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 449 | } |
| 450 | |
| 451 | nv->guid = var->guid; |
| 452 | nv->name_size = var->name_size; |
| 453 | memcpy(name, var->name, var->name_size); |
| 454 | mvar->status = EFI_SUCCESS; |
| 455 | return length; |
| 456 | } |
| 457 | |
| 458 | static bool uefi_vars_mm_digest_compare(uefi_variable *old_var, |
| 459 | uefi_variable *new_var) |
| 460 | { |
| 461 | if (!old_var->digest || |
| 462 | !new_var->digest || |
| 463 | !old_var->digest_size || |
| 464 | !new_var->digest_size) { |
| 465 | /* should not happen */ |
| 466 | trace_uefi_vars_security_violation("inconsistent authvar digest state"); |
| 467 | return false; |
| 468 | } |
| 469 | if (old_var->digest_size != new_var->digest_size) { |
| 470 | trace_uefi_vars_security_violation("authvar digest size mismatch"); |
| 471 | return false; |
| 472 | } |
| 473 | if (memcmp(old_var->digest, new_var->digest, |
| 474 | old_var->digest_size) != 0) { |
| 475 | trace_uefi_vars_security_violation("authvar digest data mismatch"); |
| 476 | return false; |
| 477 | } |
| 478 | return true; |
| 479 | } |
| 480 | |
| 481 | static size_t uefi_vars_mm_set_variable(uefi_vars_state *uv, mm_header *mhdr, |
| 482 | mm_variable *mvar, void *func) |
| 483 | { |
| 484 | mm_variable_access *va = func; |
| 485 | uint32_t attributes = 0; |
| 486 | uint16_t *name; |
| 487 | void *data; |
| 488 | uefi_variable *old_var, *new_var; |
| 489 | uint64_t length; |
| 490 | size_t new_storage; |
| 491 | efi_status status; |
| 492 | |
| 493 | length = sizeof(*mvar) + sizeof(*va); |
| 494 | if (mhdr->length < length) { |
| 495 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 496 | } |
| 497 | |
| 498 | if (va->name_size > uv->max_storage || |
| 499 | va->data_size > uv->max_storage) { |
| 500 | return uefi_vars_mm_error(mhdr, mvar, EFI_OUT_OF_RESOURCES); |
| 501 | } |
| 502 | |
| 503 | name = func + sizeof(*va); |
| 504 | if (uadd64_overflow(length, va->name_size, &length)) { |
| 505 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 506 | } |
| 507 | if (mhdr->length < length) { |
| 508 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 509 | } |
| 510 | |
| 511 | data = func + sizeof(*va) + va->name_size; |
| 512 | if (uadd64_overflow(length, va->data_size, &length)) { |
| 513 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 514 | } |
| 515 | if (mhdr->length < length) { |
| 516 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 517 | } |
| 518 | |
| 519 | g_assert(va->name_size < G_MAXUINT32); |
| 520 | g_assert(va->data_size < G_MAXUINT32); |
| 521 | |
| 522 | if (!uefi_str_is_valid(name, va->name_size, true)) { |
| 523 | return uefi_vars_mm_error(mhdr, mvar, EFI_INVALID_PARAMETER); |
| 524 | } |
| 525 | |
| 526 | uefi_trace_variable(__func__, va->guid, name, va->name_size); |
| 527 | |
| 528 | old_var = uefi_vars_find_variable(uv, va->guid, name, va->name_size); |
| 529 | if (va->data_size) { |
| 530 | new_var = add_variable(uv, va->guid, name, va->name_size, |
| 531 | va->attributes); |
| 532 | if (va->attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS) { |
| 533 | /* not implemented (deprecated in uefi spec) */ |
| 534 | warn_report("%s: AUTHENTICATED_WRITE_ACCESS", __func__); |
| 535 | mvar->status = EFI_UNSUPPORTED; |
| 536 | goto rollback; |
| 537 | } else if (va->attributes & |
| 538 | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) { |
| 539 | status = uefi_vars_check_auth_2(uv, new_var, va, data); |
| 540 | if (status != EFI_SUCCESS) { |
| 541 | mvar->status = status; |
| 542 | goto rollback; |
| 543 | } |
| 544 | if (old_var && new_var) { |
| 545 | if ((va->attributes & EFI_VARIABLE_APPEND_WRITE) == 0 && |
| 546 | uefi_time_compare(&old_var->time, &new_var->time) > 0) { |
| 547 | trace_uefi_vars_security_violation("time check failed"); |
| 548 | mvar->status = EFI_SECURITY_VIOLATION; |
| 549 | goto rollback; |
| 550 | } |
| 551 | if (old_var->digest_size || new_var->digest_size) { |
| 552 | if (!uefi_vars_mm_digest_compare(old_var, new_var)) { |
| 553 | mvar->status = EFI_SECURITY_VIOLATION; |
| 554 | goto rollback; |
| 555 | } |
| 556 | } |
| 557 | } |
| 558 | } else { |
| 559 | new_var->data = g_malloc(va->data_size); |
| 560 | memcpy(new_var->data, data, va->data_size); |
| 561 | new_var->data_size = va->data_size; |
| 562 | } |
| 563 | if (!new_var->data) { |
| 564 | /* we land here when deleting authenticated variables */ |
| 565 | del_variable(uv, new_var); |
| 566 | new_var = NULL; |
| 567 | } |
| 568 | } else { |
| 569 | new_var = NULL; |
| 570 | } |
| 571 | |
| 572 | if (!old_var && !new_var) { |
| 573 | /* delete non-existing variable -> nothing to do */ |
| 574 | mvar->status = EFI_SUCCESS; |
| 575 | return sizeof(*mvar); |
| 576 | } |
| 577 | |
| 578 | /* check permissions etc. */ |
| 579 | status = check_update(uv, old_var, new_var); |
| 580 | if (status != EFI_SUCCESS) { |
| 581 | mvar->status = status; |
| 582 | goto rollback; |
| 583 | } |
| 584 | |
| 585 | if (va->attributes & EFI_VARIABLE_APPEND_WRITE && old_var && new_var) { |
| 586 | /* merge signature databases */ |
| 587 | if (!uefi_vars_is_sb_any(new_var)) { |
| 588 | mvar->status = EFI_UNSUPPORTED; |
| 589 | goto rollback; |
| 590 | } |
| 591 | append_write(old_var, new_var); |
| 592 | } |
| 593 | |
| 594 | /* check storage space */ |
| 595 | new_storage = uv->used_storage; |
| 596 | if (old_var) { |
| 597 | new_storage -= variable_size(old_var); |
| 598 | } |
| 599 | if (new_var) { |
| 600 | new_storage += variable_size(new_var); |
| 601 | } |
| 602 | if (new_storage > uv->max_storage) { |
| 603 | mvar->status = EFI_OUT_OF_RESOURCES; |
| 604 | goto rollback; |
| 605 | } |
| 606 | |
| 607 | attributes = new_var |
| 608 | ? new_var->attributes |
| 609 | : old_var->attributes; |
| 610 | |
| 611 | /* all good, commit */ |
| 612 | del_variable(uv, old_var); |
| 613 | uv->used_storage = new_storage; |
| 614 | |
| 615 | if (attributes & EFI_VARIABLE_NON_VOLATILE) { |
| 616 | uefi_vars_json_save(uv); |
| 617 | } |
| 618 | |
| 619 | if (new_var && uefi_vars_is_sb_pk(new_var)) { |
| 620 | uefi_vars_auth_init(uv); |
| 621 | } |
| 622 | |
| 623 | mvar->status = EFI_SUCCESS; |
| 624 | return sizeof(*mvar); |
| 625 | |
| 626 | rollback: |
| 627 | del_variable(uv, new_var); |
| 628 | return sizeof(*mvar); |
| 629 | } |
| 630 | |
| 631 | static size_t uefi_vars_mm_variable_info(uefi_vars_state *uv, mm_header *mhdr, |
| 632 | mm_variable *mvar, void *func) |
| 633 | { |
| 634 | mm_variable_info *vi = func; |
| 635 | uint64_t length; |
| 636 | |
| 637 | length = sizeof(*mvar) + sizeof(*vi); |
| 638 | if (!check_buffer_size(uv, length)) { |
| 639 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 640 | } |
| 641 | |
| 642 | vi->max_storage_size = uv->max_storage; |
| 643 | vi->free_storage_size = uv->max_storage - uv->used_storage; |
| 644 | vi->max_variable_size = uv->max_storage >> 2; |
| 645 | vi->attributes = 0; |
| 646 | |
| 647 | mvar->status = EFI_SUCCESS; |
| 648 | return length; |
| 649 | } |
| 650 | |
| 651 | static size_t |
| 652 | uefi_vars_mm_get_payload_size(uefi_vars_state *uv, mm_header *mhdr, |
| 653 | mm_variable *mvar, void *func) |
| 654 | { |
| 655 | mm_get_payload_size *ps = func; |
| 656 | uint64_t length; |
| 657 | |
| 658 | length = sizeof(*mvar) + sizeof(*ps); |
| 659 | if (!check_buffer_size(uv, length)) { |
| 660 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 661 | } |
| 662 | |
| 663 | ps->payload_size = uv->buf_size - sizeof(*mhdr) - sizeof(*mvar); |
| 664 | mvar->status = EFI_SUCCESS; |
| 665 | return length; |
| 666 | } |
| 667 | |
| 668 | static size_t |
| 669 | uefi_vars_mm_lock_variable(uefi_vars_state *uv, mm_header *mhdr, |
| 670 | mm_variable *mvar, void *func) |
| 671 | { |
| 672 | mm_lock_variable *lv = func; |
| 673 | variable_policy_entry *pe; |
| 674 | uint16_t *name, *dest; |
| 675 | uint64_t length; |
| 676 | |
| 677 | length = sizeof(*mvar) + sizeof(*lv); |
| 678 | if (mhdr->length < length) { |
| 679 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 680 | } |
| 681 | |
| 682 | name = func + sizeof(*lv); |
| 683 | if (uadd64_overflow(length, lv->name_size, &length)) { |
| 684 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 685 | } |
| 686 | if (mhdr->length < length) { |
| 687 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 688 | } |
| 689 | if (sizeof(*pe) + lv->name_size > UINT16_MAX) { |
| 690 | return uefi_vars_mm_error(mhdr, mvar, EFI_BAD_BUFFER_SIZE); |
| 691 | } |
| 692 | |
| 693 | uefi_trace_variable(__func__, lv->guid, name, lv->name_size); |
| 694 | |
| 695 | pe = g_malloc0(sizeof(*pe) + lv->name_size); |
| 696 | pe->version = VARIABLE_POLICY_ENTRY_REVISION; |
| 697 | pe->size = sizeof(*pe) + lv->name_size; |
| 698 | pe->offset_to_name = sizeof(*pe); |
| 699 | pe->namespace = lv->guid; |
| 700 | pe->min_size = 0; |
| 701 | pe->max_size = UINT32_MAX; |
| 702 | pe->attributes_must_have = 0; |
| 703 | pe->attributes_cant_have = 0; |
| 704 | pe->lock_policy_type = VARIABLE_POLICY_TYPE_LOCK_NOW; |
| 705 | |
| 706 | dest = (void *)pe + pe->offset_to_name; |
| 707 | memcpy(dest, name, lv->name_size); |
| 708 | |
| 709 | uefi_vars_add_policy(uv, pe); |
| 710 | g_free(pe); |
| 711 | |
| 712 | mvar->status = EFI_SUCCESS; |
| 713 | return length; |
| 714 | } |
| 715 | |
| 716 | uint32_t uefi_vars_mm_vars_proto(uefi_vars_state *uv) |
| 717 | { |
| 718 | static const char *fnames[] = { |
| 719 | "zero", |
| 720 | "get-variable", |
| 721 | "get-next-variable-name", |
| 722 | "set-variable", |
| 723 | "query-variable-info", |
| 724 | "ready-to-boot", |
| 725 | "exit-boot-service", |
| 726 | "get-statistics", |
| 727 | "lock-variable", |
| 728 | "var-check-prop-set", |
| 729 | "var-check-prop-get", |
| 730 | "get-payload-size", |
| 731 | "init-runtime-cache-contect", |
| 732 | "sync-runtime-cache", |
| 733 | "get-runtime-cache-info", |
| 734 | }; |
| 735 | const char *fname; |
| 736 | uint64_t length; |
| 737 | |
| 738 | mm_header *mhdr = (mm_header *) uv->buffer; |
| 739 | mm_variable *mvar = (mm_variable *) (uv->buffer + sizeof(*mhdr)); |
| 740 | void *func = (uv->buffer + sizeof(*mhdr) + sizeof(*mvar)); |
| 741 | |
| 742 | if (mhdr->length < sizeof(*mvar)) { |
| 743 | return UEFI_VARS_STS_ERR_BAD_BUFFER_SIZE; |
| 744 | } |
| 745 | |
| 746 | fname = mvar->function < ARRAY_SIZE(fnames) |
| 747 | ? fnames[mvar->function] |
| 748 | : "unknown"; |
| 749 | trace_uefi_vars_proto_cmd(fname); |
| 750 | |
| 751 | switch (mvar->function) { |
| 752 | case SMM_VARIABLE_FUNCTION_GET_VARIABLE: |
| 753 | length = uefi_vars_mm_get_variable(uv, mhdr, mvar, func); |
| 754 | break; |
| 755 | |
| 756 | case SMM_VARIABLE_FUNCTION_GET_NEXT_VARIABLE_NAME: |
| 757 | length = uefi_vars_mm_get_next_variable(uv, mhdr, mvar, func); |
| 758 | break; |
| 759 | |
| 760 | case SMM_VARIABLE_FUNCTION_SET_VARIABLE: |
| 761 | length = uefi_vars_mm_set_variable(uv, mhdr, mvar, func); |
| 762 | break; |
| 763 | |
| 764 | case SMM_VARIABLE_FUNCTION_QUERY_VARIABLE_INFO: |
| 765 | length = uefi_vars_mm_variable_info(uv, mhdr, mvar, func); |
| 766 | break; |
| 767 | |
| 768 | case SMM_VARIABLE_FUNCTION_LOCK_VARIABLE: |
| 769 | length = uefi_vars_mm_lock_variable(uv, mhdr, mvar, func); |
| 770 | break; |
| 771 | |
| 772 | case SMM_VARIABLE_FUNCTION_GET_PAYLOAD_SIZE: |
| 773 | length = uefi_vars_mm_get_payload_size(uv, mhdr, mvar, func); |
| 774 | break; |
| 775 | |
| 776 | case SMM_VARIABLE_FUNCTION_READY_TO_BOOT: |
| 777 | trace_uefi_event("ready-to-boot"); |
| 778 | uv->ready_to_boot = true; |
| 779 | mvar->status = EFI_SUCCESS; |
| 780 | length = 0; |
| 781 | break; |
| 782 | |
| 783 | case SMM_VARIABLE_FUNCTION_EXIT_BOOT_SERVICE: |
| 784 | trace_uefi_event("exit-boot-service"); |
| 785 | uv->exit_boot_service = true; |
| 786 | mvar->status = EFI_SUCCESS; |
| 787 | length = 0; |
| 788 | break; |
| 789 | |
| 790 | default: |
| 791 | length = uefi_vars_mm_error(mhdr, mvar, EFI_UNSUPPORTED); |
| 792 | break; |
| 793 | } |
| 794 | |
| 795 | if (mhdr->length < length) { |
| 796 | mvar->status = EFI_BUFFER_TOO_SMALL; |
| 797 | } |
| 798 | |
| 799 | uefi_trace_status(__func__, mvar->status); |
| 800 | return UEFI_VARS_STS_SUCCESS; |
| 801 | } |