1 /* 2 * (C) Copyright 2000 3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 #include <common.h> 9 #include <autoboot.h> 10 #include <bootretry.h> 11 #include <cli.h> 12 #include <fdtdec.h> 13 #include <menu.h> 14 #include <post.h> 15 #include <u-boot/sha256.h> 16 17 DECLARE_GLOBAL_DATA_PTR; 18 19 #define MAX_DELAY_STOP_STR 32 20 21 #ifndef DEBUG_BOOTKEYS 22 #define DEBUG_BOOTKEYS 0 23 #endif 24 #define debug_bootkeys(fmt, args...) \ 25 debug_cond(DEBUG_BOOTKEYS, fmt, ##args) 26 27 /* Stored value of bootdelay, used by autoboot_command() */ 28 static int stored_bootdelay; 29 30 #if defined(CONFIG_AUTOBOOT_KEYED) 31 #if defined(CONFIG_AUTOBOOT_STOP_STR_SHA256) 32 33 /* 34 * Use a "constant-length" time compare function for this 35 * hash compare: 36 * 37 * https://crackstation.net/hashing-security.htm 38 */ 39 static int slow_equals(u8 *a, u8 *b, int len) 40 { 41 int diff = 0; 42 int i; 43 44 for (i = 0; i < len; i++) 45 diff |= a[i] ^ b[i]; 46 47 return diff == 0; 48 } 49 50 static int passwd_abort(uint64_t etime) 51 { 52 const char *sha_env_str = getenv("bootstopkeysha256"); 53 u8 sha_env[SHA256_SUM_LEN]; 54 u8 sha[SHA256_SUM_LEN]; 55 char presskey[MAX_DELAY_STOP_STR]; 56 const char *algo_name = "sha256"; 57 u_int presskey_len = 0; 58 int abort = 0; 59 int size; 60 int ret; 61 62 if (sha_env_str == NULL) 63 sha_env_str = CONFIG_AUTOBOOT_STOP_STR_SHA256; 64 65 /* 66 * Generate the binary value from the environment hash value 67 * so that we can compare this value with the computed hash 68 * from the user input 69 */ 70 ret = hash_parse_string(algo_name, sha_env_str, sha_env); 71 if (ret) { 72 printf("Hash %s not supported!\n", algo_name); 73 return 0; 74 } 75 76 /* 77 * We don't know how long the stop-string is, so we need to 78 * generate the sha256 hash upon each input character and 79 * compare the value with the one saved in the environment 80 */ 81 do { 82 if (tstc()) { 83 /* Check for input string overflow */ 84 if (presskey_len >= MAX_DELAY_STOP_STR) 85 return 0; 86 87 presskey[presskey_len++] = getc(); 88 89 /* Calculate sha256 upon each new char */ 90 hash_block(algo_name, (const void *)presskey, 91 presskey_len, sha, &size); 92 93 /* And check if sha matches saved value in env */ 94 if (slow_equals(sha, sha_env, SHA256_SUM_LEN)) 95 abort = 1; 96 } 97 } while (!abort && get_ticks() <= etime); 98 99 return abort; 100 } 101 #else 102 static int passwd_abort(uint64_t etime) 103 { 104 int abort = 0; 105 struct { 106 char *str; 107 u_int len; 108 int retry; 109 } 110 delaykey[] = { 111 { .str = getenv("bootdelaykey"), .retry = 1 }, 112 { .str = getenv("bootstopkey"), .retry = 0 }, 113 }; 114 115 char presskey[MAX_DELAY_STOP_STR]; 116 u_int presskey_len = 0; 117 u_int presskey_max = 0; 118 u_int i; 119 120 # ifdef CONFIG_AUTOBOOT_DELAY_STR 121 if (delaykey[0].str == NULL) 122 delaykey[0].str = CONFIG_AUTOBOOT_DELAY_STR; 123 # endif 124 # ifdef CONFIG_AUTOBOOT_STOP_STR 125 if (delaykey[1].str == NULL) 126 delaykey[1].str = CONFIG_AUTOBOOT_STOP_STR; 127 # endif 128 129 for (i = 0; i < sizeof(delaykey) / sizeof(delaykey[0]); i++) { 130 delaykey[i].len = delaykey[i].str == NULL ? 131 0 : strlen(delaykey[i].str); 132 delaykey[i].len = delaykey[i].len > MAX_DELAY_STOP_STR ? 133 MAX_DELAY_STOP_STR : delaykey[i].len; 134 135 presskey_max = presskey_max > delaykey[i].len ? 136 presskey_max : delaykey[i].len; 137 138 debug_bootkeys("%s key:<%s>\n", 139 delaykey[i].retry ? "delay" : "stop", 140 delaykey[i].str ? delaykey[i].str : "NULL"); 141 } 142 143 /* In order to keep up with incoming data, check timeout only 144 * when catch up. 145 */ 146 do { 147 if (tstc()) { 148 if (presskey_len < presskey_max) { 149 presskey[presskey_len++] = getc(); 150 } else { 151 for (i = 0; i < presskey_max - 1; i++) 152 presskey[i] = presskey[i + 1]; 153 154 presskey[i] = getc(); 155 } 156 } 157 158 for (i = 0; i < sizeof(delaykey) / sizeof(delaykey[0]); i++) { 159 if (delaykey[i].len > 0 && 160 presskey_len >= delaykey[i].len && 161 memcmp(presskey + presskey_len - 162 delaykey[i].len, delaykey[i].str, 163 delaykey[i].len) == 0) { 164 debug_bootkeys("got %skey\n", 165 delaykey[i].retry ? "delay" : 166 "stop"); 167 168 /* don't retry auto boot */ 169 if (!delaykey[i].retry) 170 bootretry_dont_retry(); 171 abort = 1; 172 } 173 } 174 } while (!abort && get_ticks() <= etime); 175 176 return abort; 177 } 178 #endif 179 180 /*************************************************************************** 181 * Watch for 'delay' seconds for autoboot stop or autoboot delay string. 182 * returns: 0 - no key string, allow autoboot 1 - got key string, abort 183 */ 184 static int abortboot_keyed(int bootdelay) 185 { 186 int abort; 187 uint64_t etime = endtick(bootdelay); 188 189 #ifndef CONFIG_ZERO_BOOTDELAY_CHECK 190 if (bootdelay == 0) 191 return 0; 192 #endif 193 194 # ifdef CONFIG_AUTOBOOT_PROMPT 195 /* 196 * CONFIG_AUTOBOOT_PROMPT includes the %d for all boards. 197 * To print the bootdelay value upon bootup. 198 */ 199 printf(CONFIG_AUTOBOOT_PROMPT, bootdelay); 200 # endif 201 202 abort = passwd_abort(etime); 203 if (!abort) 204 debug_bootkeys("key timeout\n"); 205 206 #ifdef CONFIG_SILENT_CONSOLE 207 if (abort) 208 gd->flags &= ~GD_FLG_SILENT; 209 #endif 210 211 return abort; 212 } 213 214 # else /* !defined(CONFIG_AUTOBOOT_KEYED) */ 215 216 #ifdef CONFIG_MENUKEY 217 static int menukey; 218 #endif 219 220 static int abortboot_normal(int bootdelay) 221 { 222 int abort = 0; 223 unsigned long ts; 224 225 #ifdef CONFIG_MENUPROMPT 226 printf(CONFIG_MENUPROMPT); 227 #else 228 if (bootdelay >= 0) 229 printf("Hit any key to stop autoboot: %2d ", bootdelay); 230 #endif 231 232 #if defined CONFIG_ZERO_BOOTDELAY_CHECK 233 /* 234 * Check if key already pressed 235 * Don't check if bootdelay < 0 236 */ 237 if (bootdelay >= 0) { 238 if (tstc()) { /* we got a key press */ 239 (void) getc(); /* consume input */ 240 puts("\b\b\b 0"); 241 abort = 1; /* don't auto boot */ 242 } 243 } 244 #endif 245 246 while ((bootdelay > 0) && (!abort)) { 247 --bootdelay; 248 /* delay 1000 ms */ 249 ts = get_timer(0); 250 do { 251 if (tstc()) { /* we got a key press */ 252 abort = 1; /* don't auto boot */ 253 bootdelay = 0; /* no more delay */ 254 # ifdef CONFIG_MENUKEY 255 menukey = getc(); 256 # else 257 (void) getc(); /* consume input */ 258 # endif 259 break; 260 } 261 udelay(10000); 262 } while (!abort && get_timer(ts) < 1000); 263 264 printf("\b\b\b%2d ", bootdelay); 265 } 266 267 putc('\n'); 268 269 #ifdef CONFIG_SILENT_CONSOLE 270 if (abort) 271 gd->flags &= ~GD_FLG_SILENT; 272 #endif 273 274 return abort; 275 } 276 # endif /* CONFIG_AUTOBOOT_KEYED */ 277 278 static int abortboot(int bootdelay) 279 { 280 #ifdef CONFIG_AUTOBOOT_KEYED 281 return abortboot_keyed(bootdelay); 282 #else 283 return abortboot_normal(bootdelay); 284 #endif 285 } 286 287 static void process_fdt_options(const void *blob) 288 { 289 #if defined(CONFIG_OF_CONTROL) 290 ulong addr; 291 292 /* Add an env variable to point to a kernel payload, if available */ 293 addr = fdtdec_get_config_int(gd->fdt_blob, "kernel-offset", 0); 294 if (addr) 295 setenv_addr("kernaddr", (void *)(CONFIG_SYS_TEXT_BASE + addr)); 296 297 /* Add an env variable to point to a root disk, if available */ 298 addr = fdtdec_get_config_int(gd->fdt_blob, "rootdisk-offset", 0); 299 if (addr) 300 setenv_addr("rootaddr", (void *)(CONFIG_SYS_TEXT_BASE + addr)); 301 #endif /* CONFIG_OF_CONTROL */ 302 } 303 304 const char *bootdelay_process(void) 305 { 306 char *s; 307 int bootdelay; 308 #ifdef CONFIG_BOOTCOUNT_LIMIT 309 unsigned long bootcount = 0; 310 unsigned long bootlimit = 0; 311 #endif /* CONFIG_BOOTCOUNT_LIMIT */ 312 313 #ifdef CONFIG_BOOTCOUNT_LIMIT 314 bootcount = bootcount_load(); 315 bootcount++; 316 bootcount_store(bootcount); 317 setenv_ulong("bootcount", bootcount); 318 bootlimit = getenv_ulong("bootlimit", 10, 0); 319 #endif /* CONFIG_BOOTCOUNT_LIMIT */ 320 321 s = getenv("bootdelay"); 322 bootdelay = s ? (int)simple_strtol(s, NULL, 10) : CONFIG_BOOTDELAY; 323 324 #ifdef CONFIG_OF_CONTROL 325 bootdelay = fdtdec_get_config_int(gd->fdt_blob, "bootdelay", 326 bootdelay); 327 #endif 328 329 debug("### main_loop entered: bootdelay=%d\n\n", bootdelay); 330 331 #if defined(CONFIG_MENU_SHOW) 332 bootdelay = menu_show(bootdelay); 333 #endif 334 bootretry_init_cmd_timeout(); 335 336 #ifdef CONFIG_POST 337 if (gd->flags & GD_FLG_POSTFAIL) { 338 s = getenv("failbootcmd"); 339 } else 340 #endif /* CONFIG_POST */ 341 #ifdef CONFIG_BOOTCOUNT_LIMIT 342 if (bootlimit && (bootcount > bootlimit)) { 343 printf("Warning: Bootlimit (%u) exceeded. Using altbootcmd.\n", 344 (unsigned)bootlimit); 345 s = getenv("altbootcmd"); 346 } else 347 #endif /* CONFIG_BOOTCOUNT_LIMIT */ 348 s = getenv("bootcmd"); 349 350 process_fdt_options(gd->fdt_blob); 351 stored_bootdelay = bootdelay; 352 353 return s; 354 } 355 356 void autoboot_command(const char *s) 357 { 358 debug("### main_loop: bootcmd=\"%s\"\n", s ? s : "<UNDEFINED>"); 359 360 if (stored_bootdelay != -1 && s && !abortboot(stored_bootdelay)) { 361 #if defined(CONFIG_AUTOBOOT_KEYED) && !defined(CONFIG_AUTOBOOT_KEYED_CTRLC) 362 int prev = disable_ctrlc(1); /* disable Control C checking */ 363 #endif 364 365 run_command_list(s, -1, 0); 366 367 #if defined(CONFIG_AUTOBOOT_KEYED) && !defined(CONFIG_AUTOBOOT_KEYED_CTRLC) 368 disable_ctrlc(prev); /* restore Control C checking */ 369 #endif 370 } 371 372 #ifdef CONFIG_MENUKEY 373 if (menukey == CONFIG_MENUKEY) { 374 s = getenv("menucmd"); 375 if (s) 376 run_command_list(s, -1, 0); 377 } 378 #endif /* CONFIG_MENUKEY */ 379 } 380