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