1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Integrate UEFI variables to u-boot env interface 4 * 5 * Copyright (c) 2018 AKASHI Takahiro, Linaro Limited 6 */ 7 8 #include <charset.h> 9 #include <common.h> 10 #include <command.h> 11 #include <efi_loader.h> 12 #include <exports.h> 13 #include <hexdump.h> 14 #include <malloc.h> 15 #include <linux/kernel.h> 16 17 /* 18 * From efi_variable.c, 19 * 20 * Mapping between UEFI variables and u-boot variables: 21 * 22 * efi_$guid_$varname = {attributes}(type)value 23 */ 24 25 static const struct { 26 u32 mask; 27 char *text; 28 } efi_var_attrs[] = { 29 {EFI_VARIABLE_NON_VOLATILE, "NV"}, 30 {EFI_VARIABLE_BOOTSERVICE_ACCESS, "BS"}, 31 {EFI_VARIABLE_RUNTIME_ACCESS, "RT"}, 32 {EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS, "AW"}, 33 {EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS, "AT"}, 34 }; 35 36 /** 37 * efi_dump_single_var() - show information about a UEFI variable 38 * 39 * @name: Name of the variable 40 * @guid: Vendor GUID 41 * 42 * Show information encoded in one UEFI variable 43 */ 44 static void efi_dump_single_var(u16 *name, efi_guid_t *guid) 45 { 46 u32 attributes; 47 u8 *data; 48 efi_uintn_t size; 49 int count, i; 50 efi_status_t ret; 51 52 data = NULL; 53 size = 0; 54 ret = EFI_CALL(efi_get_variable(name, guid, &attributes, &size, data)); 55 if (ret == EFI_BUFFER_TOO_SMALL) { 56 data = malloc(size); 57 if (!data) 58 goto out; 59 60 ret = EFI_CALL(efi_get_variable(name, guid, &attributes, &size, 61 data)); 62 } 63 if (ret == EFI_NOT_FOUND) { 64 printf("Error: \"%ls\" not defined\n", name); 65 goto out; 66 } 67 if (ret != EFI_SUCCESS) 68 goto out; 69 70 printf("%ls:", name); 71 for (count = 0, i = 0; i < ARRAY_SIZE(efi_var_attrs); i++) 72 if (attributes & efi_var_attrs[i].mask) { 73 if (count) 74 putc('|'); 75 else 76 putc(' '); 77 count++; 78 puts(efi_var_attrs[i].text); 79 } 80 printf(", DataSize = 0x%zx\n", size); 81 print_hex_dump(" ", DUMP_PREFIX_OFFSET, 16, 1, data, size, true); 82 83 out: 84 free(data); 85 } 86 87 /** 88 * efi_dump_vars() - show information about named UEFI variables 89 * 90 * @argc: Number of arguments (variables) 91 * @argv: Argument (variable name) array 92 * Return: CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE 93 * 94 * Show information encoded in named UEFI variables 95 */ 96 static int efi_dump_vars(int argc, char * const argv[]) 97 { 98 u16 *var_name16, *p; 99 efi_uintn_t buf_size, size; 100 101 buf_size = 128; 102 var_name16 = malloc(buf_size); 103 if (!var_name16) 104 return CMD_RET_FAILURE; 105 106 for (; argc > 0; argc--, argv++) { 107 size = (utf8_utf16_strlen(argv[0]) + 1) * sizeof(u16); 108 if (buf_size < size) { 109 buf_size = size; 110 p = realloc(var_name16, buf_size); 111 if (!p) { 112 free(var_name16); 113 return CMD_RET_FAILURE; 114 } 115 var_name16 = p; 116 } 117 118 p = var_name16; 119 utf8_utf16_strcpy(&p, argv[0]); 120 121 efi_dump_single_var(var_name16, 122 (efi_guid_t *)&efi_global_variable_guid); 123 } 124 125 free(var_name16); 126 127 return CMD_RET_SUCCESS; 128 } 129 130 /** 131 * efi_dump_vars() - show information about all the UEFI variables 132 * 133 * Return: CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE 134 * 135 * Show information encoded in all the UEFI variables 136 */ 137 static int efi_dump_var_all(void) 138 { 139 u16 *var_name16, *p; 140 efi_uintn_t buf_size, size; 141 efi_guid_t guid; 142 efi_status_t ret; 143 144 buf_size = 128; 145 var_name16 = malloc(buf_size); 146 if (!var_name16) 147 return CMD_RET_FAILURE; 148 149 var_name16[0] = 0; 150 for (;;) { 151 size = buf_size; 152 ret = EFI_CALL(efi_get_next_variable_name(&size, var_name16, 153 &guid)); 154 if (ret == EFI_NOT_FOUND) 155 break; 156 if (ret == EFI_BUFFER_TOO_SMALL) { 157 buf_size = size; 158 p = realloc(var_name16, buf_size); 159 if (!p) { 160 free(var_name16); 161 return CMD_RET_FAILURE; 162 } 163 var_name16 = p; 164 ret = EFI_CALL(efi_get_next_variable_name(&size, 165 var_name16, 166 &guid)); 167 } 168 if (ret != EFI_SUCCESS) { 169 free(var_name16); 170 return CMD_RET_FAILURE; 171 } 172 173 efi_dump_single_var(var_name16, &guid); 174 } 175 176 free(var_name16); 177 178 return CMD_RET_SUCCESS; 179 } 180 181 /** 182 * do_env_print_efi() - show information about UEFI variables 183 * 184 * @cmdtp: Command table 185 * @flag: Command flag 186 * @argc: Number of arguments 187 * @argv: Argument array 188 * Return: CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE 189 * 190 * This function is for "env print -e" or "printenv -e" command: 191 * => env print -e [var [...]] 192 * If one or more variable names are specified, show information 193 * named UEFI variables, otherwise show all the UEFI variables. 194 */ 195 int do_env_print_efi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) 196 { 197 efi_status_t ret; 198 199 /* Initialize EFI drivers */ 200 ret = efi_init_obj_list(); 201 if (ret != EFI_SUCCESS) { 202 printf("Error: Cannot initialize UEFI sub-system, r = %lu\n", 203 ret & ~EFI_ERROR_MASK); 204 return CMD_RET_FAILURE; 205 } 206 207 if (argc > 1) 208 /* show specified UEFI variables */ 209 return efi_dump_vars(--argc, ++argv); 210 211 /* enumerate and show all UEFI variables */ 212 return efi_dump_var_all(); 213 } 214 215 /** 216 * append_value() - encode UEFI variable's value 217 * @bufp: Buffer of encoded UEFI variable's value 218 * @sizep: Size of buffer 219 * @data: data to be encoded into the value 220 * Return: 0 on success, -1 otherwise 221 * 222 * Interpret a given data string and append it to buffer. 223 * Buffer will be realloc'ed if necessary. 224 * 225 * Currently supported formats are: 226 * =0x0123...: Hexadecimal number 227 * =H0123...: Hexadecimal-byte array 228 * ="...", =S"..." or <string>: 229 * String 230 */ 231 static int append_value(char **bufp, size_t *sizep, char *data) 232 { 233 char *tmp_buf = NULL, *new_buf = NULL, *value; 234 unsigned long len = 0; 235 236 if (!strncmp(data, "=0x", 2)) { /* hexadecimal number */ 237 union { 238 u8 u8; 239 u16 u16; 240 u32 u32; 241 u64 u64; 242 } tmp_data; 243 unsigned long hex_value; 244 void *hex_ptr; 245 246 data += 3; 247 len = strlen(data); 248 if ((len & 0x1)) /* not multiple of two */ 249 return -1; 250 251 len /= 2; 252 if (len > 8) 253 return -1; 254 else if (len > 4) 255 len = 8; 256 else if (len > 2) 257 len = 4; 258 259 /* convert hex hexadecimal number */ 260 if (strict_strtoul(data, 16, &hex_value) < 0) 261 return -1; 262 263 tmp_buf = malloc(len); 264 if (!tmp_buf) 265 return -1; 266 267 if (len == 1) { 268 tmp_data.u8 = hex_value; 269 hex_ptr = &tmp_data.u8; 270 } else if (len == 2) { 271 tmp_data.u16 = hex_value; 272 hex_ptr = &tmp_data.u16; 273 } else if (len == 4) { 274 tmp_data.u32 = hex_value; 275 hex_ptr = &tmp_data.u32; 276 } else { 277 tmp_data.u64 = hex_value; 278 hex_ptr = &tmp_data.u64; 279 } 280 memcpy(tmp_buf, hex_ptr, len); 281 value = tmp_buf; 282 283 } else if (!strncmp(data, "=H", 2)) { /* hexadecimal-byte array */ 284 data += 2; 285 len = strlen(data); 286 if (len & 0x1) /* not multiple of two */ 287 return -1; 288 289 len /= 2; 290 tmp_buf = malloc(len); 291 if (!tmp_buf) 292 return -1; 293 294 if (hex2bin((u8 *)tmp_buf, data, len) < 0) 295 return -1; 296 297 value = tmp_buf; 298 } else { /* string */ 299 if (!strncmp(data, "=\"", 2) || !strncmp(data, "=S\"", 3)) { 300 if (data[1] == '"') 301 data += 2; 302 else 303 data += 3; 304 value = data; 305 len = strlen(data) - 1; 306 if (data[len] != '"') 307 return -1; 308 } else { 309 value = data; 310 len = strlen(data); 311 } 312 } 313 314 new_buf = realloc(*bufp, *sizep + len); 315 if (!new_buf) 316 goto out; 317 318 memcpy(new_buf + *sizep, value, len); 319 *bufp = new_buf; 320 *sizep += len; 321 322 out: 323 free(tmp_buf); 324 325 return 0; 326 } 327 328 /** 329 * do_env_print_efi() - set UEFI variable 330 * 331 * @cmdtp: Command table 332 * @flag: Command flag 333 * @argc: Number of arguments 334 * @argv: Argument array 335 * Return: CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE 336 * 337 * This function is for "env set -e" or "setenv -e" command: 338 * => env set -e var [value ...]] 339 * Encode values specified and set given UEFI variable. 340 * If no value is specified, delete the variable. 341 */ 342 int do_env_set_efi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) 343 { 344 char *var_name, *value = NULL; 345 efi_uintn_t size = 0; 346 u16 *var_name16 = NULL, *p; 347 size_t len; 348 efi_guid_t guid; 349 efi_status_t ret; 350 351 if (argc == 1) 352 return CMD_RET_USAGE; 353 354 /* Initialize EFI drivers */ 355 ret = efi_init_obj_list(); 356 if (ret != EFI_SUCCESS) { 357 printf("Error: Cannot initialize UEFI sub-system, r = %lu\n", 358 ret & ~EFI_ERROR_MASK); 359 return CMD_RET_FAILURE; 360 } 361 362 var_name = argv[1]; 363 if (argc == 2) { 364 /* delete */ 365 value = NULL; 366 size = 0; 367 } else { /* set */ 368 argc -= 2; 369 argv += 2; 370 371 for ( ; argc > 0; argc--, argv++) 372 if (append_value(&value, &size, argv[0]) < 0) { 373 ret = CMD_RET_FAILURE; 374 goto out; 375 } 376 } 377 378 len = utf8_utf16_strnlen(var_name, strlen(var_name)); 379 var_name16 = malloc((len + 1) * 2); 380 if (!var_name16) { 381 ret = CMD_RET_FAILURE; 382 goto out; 383 } 384 p = var_name16; 385 utf8_utf16_strncpy(&p, var_name, len + 1); 386 387 guid = efi_global_variable_guid; 388 ret = EFI_CALL(efi_set_variable(var_name16, &guid, 389 EFI_VARIABLE_BOOTSERVICE_ACCESS | 390 EFI_VARIABLE_RUNTIME_ACCESS, 391 size, value)); 392 ret = (ret == EFI_SUCCESS ? CMD_RET_SUCCESS : CMD_RET_FAILURE); 393 out: 394 free(value); 395 free(var_name16); 396 397 return ret; 398 } 399