common/main.c

/*
 * (C) Copyright 2000
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

/* #define	DEBUG	*/

#include <common.h>
#include <cli.h>
#include <command.h>
#include <fdtdec.h>
#include <cli_hush.h>
#include <malloc.h>
#include <menu.h>
#include <post.h>
#include <version.h>

DECLARE_GLOBAL_DATA_PTR;

/*
 * Board-specific Platform code can reimplement show_boot_progress () if needed
 */
void inline __show_boot_progress (int val) {}
void show_boot_progress (int val) __attribute__((weak, alias("__show_boot_progress")));

#define MAX_DELAY_STOP_STR 32

#ifndef DEBUG_BOOTKEYS
#define DEBUG_BOOTKEYS 0
#endif
#define debug_bootkeys(fmt, args...)		\
	debug_cond(DEBUG_BOOTKEYS, fmt, ##args)

#ifdef CONFIG_MODEM_SUPPORT
int do_mdm_init = 0;
extern void mdm_init(void); /* defined in board.c */
#endif

/***************************************************************************
 * Watch for 'delay' seconds for autoboot stop or autoboot delay string.
 * returns: 0 -  no key string, allow autoboot 1 - got key string, abort
 */
#if defined(CONFIG_BOOTDELAY)
# if defined(CONFIG_AUTOBOOT_KEYED)
static int abortboot_keyed(int bootdelay)
{
	int abort = 0;
	uint64_t etime = endtick(bootdelay);
	struct {
		char* str;
		u_int len;
		int retry;
	}
	delaykey [] = {
		{ str: getenv ("bootdelaykey"),  retry: 1 },
		{ str: getenv ("bootdelaykey2"), retry: 1 },
		{ str: getenv ("bootstopkey"),   retry: 0 },
		{ str: getenv ("bootstopkey2"),  retry: 0 },
	};

	char presskey [MAX_DELAY_STOP_STR];
	u_int presskey_len = 0;
	u_int presskey_max = 0;
	u_int i;

#ifndef CONFIG_ZERO_BOOTDELAY_CHECK
	if (bootdelay == 0)
		return 0;
#endif

#  ifdef CONFIG_AUTOBOOT_PROMPT
	printf(CONFIG_AUTOBOOT_PROMPT);
#  endif

#  ifdef CONFIG_AUTOBOOT_DELAY_STR
	if (delaykey[0].str == NULL)
		delaykey[0].str = CONFIG_AUTOBOOT_DELAY_STR;
#  endif
#  ifdef CONFIG_AUTOBOOT_DELAY_STR2
	if (delaykey[1].str == NULL)
		delaykey[1].str = CONFIG_AUTOBOOT_DELAY_STR2;
#  endif
#  ifdef CONFIG_AUTOBOOT_STOP_STR
	if (delaykey[2].str == NULL)
		delaykey[2].str = CONFIG_AUTOBOOT_STOP_STR;
#  endif
#  ifdef CONFIG_AUTOBOOT_STOP_STR2
	if (delaykey[3].str == NULL)
		delaykey[3].str = CONFIG_AUTOBOOT_STOP_STR2;
#  endif

	for (i = 0; i < sizeof(delaykey) / sizeof(delaykey[0]); i ++) {
		delaykey[i].len = delaykey[i].str == NULL ?
				    0 : strlen (delaykey[i].str);
		delaykey[i].len = delaykey[i].len > MAX_DELAY_STOP_STR ?
				    MAX_DELAY_STOP_STR : delaykey[i].len;

		presskey_max = presskey_max > delaykey[i].len ?
				    presskey_max : delaykey[i].len;

		debug_bootkeys("%s key:<%s>\n",
			       delaykey[i].retry ? "delay" : "stop",
			       delaykey[i].str ? delaykey[i].str : "NULL");
	}

	/* In order to keep up with incoming data, check timeout only
	 * when catch up.
	 */
	do {
		if (tstc()) {
			if (presskey_len < presskey_max) {
				presskey [presskey_len ++] = getc();
			}
			else {
				for (i = 0; i < presskey_max - 1; i ++)
					presskey [i] = presskey [i + 1];

				presskey [i] = getc();
			}
		}

		for (i = 0; i < sizeof(delaykey) / sizeof(delaykey[0]); i ++) {
			if (delaykey[i].len > 0 &&
			    presskey_len >= delaykey[i].len &&
			    memcmp (presskey + presskey_len - delaykey[i].len,
				    delaykey[i].str,
				    delaykey[i].len) == 0) {
				debug_bootkeys("got %skey\n",
					       delaykey[i].retry ? "delay" :
					       "stop");

#  ifdef CONFIG_BOOT_RETRY_TIME
				/* don't retry auto boot */
				if (! delaykey[i].retry)
					bootretry_dont_retry();
#  endif
				abort = 1;
			}
		}
	} while (!abort && get_ticks() <= etime);

	if (!abort)
		debug_bootkeys("key timeout\n");

#ifdef CONFIG_SILENT_CONSOLE
	if (abort)
		gd->flags &= ~GD_FLG_SILENT;
#endif

	return abort;
}

# else	/* !defined(CONFIG_AUTOBOOT_KEYED) */

#ifdef CONFIG_MENUKEY
static int menukey = 0;
#endif

static int abortboot_normal(int bootdelay)
{
	int abort = 0;
	unsigned long ts;

#ifdef CONFIG_MENUPROMPT
	printf(CONFIG_MENUPROMPT);
#else
	if (bootdelay >= 0)
		printf("Hit any key to stop autoboot: %2d ", bootdelay);
#endif

#if defined CONFIG_ZERO_BOOTDELAY_CHECK
	/*
	 * Check if key already pressed
	 * Don't check if bootdelay < 0
	 */
	if (bootdelay >= 0) {
		if (tstc()) {	/* we got a key press	*/
			(void) getc();  /* consume input	*/
			puts ("\b\b\b 0");
			abort = 1;	/* don't auto boot	*/
		}
	}
#endif

	while ((bootdelay > 0) && (!abort)) {
		--bootdelay;
		/* delay 1000 ms */
		ts = get_timer(0);
		do {
			if (tstc()) {	/* we got a key press	*/
				abort  = 1;	/* don't auto boot	*/
				bootdelay = 0;	/* no more delay	*/
# ifdef CONFIG_MENUKEY
				menukey = getc();
# else
				(void) getc();  /* consume input	*/
# endif
				break;
			}
			udelay(10000);
		} while (!abort && get_timer(ts) < 1000);

		printf("\b\b\b%2d ", bootdelay);
	}

	putc('\n');

#ifdef CONFIG_SILENT_CONSOLE
	if (abort)
		gd->flags &= ~GD_FLG_SILENT;
#endif

	return abort;
}
# endif	/* CONFIG_AUTOBOOT_KEYED */

static int abortboot(int bootdelay)
{
#ifdef CONFIG_AUTOBOOT_KEYED
	return abortboot_keyed(bootdelay);
#else
	return abortboot_normal(bootdelay);
#endif
}
#endif	/* CONFIG_BOOTDELAY */

/*
 * Runs the given boot command securely.  Specifically:
 * - Doesn't run the command with the shell (run_command or parse_string_outer),
 *   since that's a lot of code surface that an attacker might exploit.
 *   Because of this, we don't do any argument parsing--the secure boot command
 *   has to be a full-fledged u-boot command.
 * - Doesn't check for keypresses before booting, since that could be a
 *   security hole; also disables Ctrl-C.
 * - Doesn't allow the command to return.
 *
 * Upon any failures, this function will drop into an infinite loop after
 * printing the error message to console.
 */

#if defined(CONFIG_BOOTDELAY) && defined(CONFIG_OF_CONTROL)
static void secure_boot_cmd(char *cmd)
{
	cmd_tbl_t *cmdtp;
	int rc;

	if (!cmd) {
		printf("## Error: Secure boot command not specified\n");
		goto err;
	}

	/* Disable Ctrl-C just in case some command is used that checks it. */
	disable_ctrlc(1);

	/* Find the command directly. */
	cmdtp = find_cmd(cmd);
	if (!cmdtp) {
		printf("## Error: \"%s\" not defined\n", cmd);
		goto err;
	}

	/* Run the command, forcing no flags and faking argc and argv. */
	rc = (cmdtp->cmd)(cmdtp, 0, 1, &cmd);

	/* Shouldn't ever return from boot command. */
	printf("## Error: \"%s\" returned (code %d)\n", cmd, rc);

err:
	/*
	 * Not a whole lot to do here.  Rebooting won't help much, since we'll
	 * just end up right back here.  Just loop.
	 */
	hang();
}

static void process_fdt_options(const void *blob)
{
	ulong addr;

	/* Add an env variable to point to a kernel payload, if available */
	addr = fdtdec_get_config_int(gd->fdt_blob, "kernel-offset", 0);
	if (addr)
		setenv_addr("kernaddr", (void *)(CONFIG_SYS_TEXT_BASE + addr));

	/* Add an env variable to point to a root disk, if available */
	addr = fdtdec_get_config_int(gd->fdt_blob, "rootdisk-offset", 0);
	if (addr)
		setenv_addr("rootaddr", (void *)(CONFIG_SYS_TEXT_BASE + addr));
}
#endif /* CONFIG_OF_CONTROL */

#ifdef CONFIG_BOOTDELAY
static void process_boot_delay(void)
{
#ifdef CONFIG_OF_CONTROL
	char *env;
#endif
	char *s;
	int bootdelay;
#ifdef CONFIG_BOOTCOUNT_LIMIT
	unsigned long bootcount = 0;
	unsigned long bootlimit = 0;
#endif /* CONFIG_BOOTCOUNT_LIMIT */

#ifdef CONFIG_BOOTCOUNT_LIMIT
	bootcount = bootcount_load();
	bootcount++;
	bootcount_store (bootcount);
	setenv_ulong("bootcount", bootcount);
	bootlimit = getenv_ulong("bootlimit", 10, 0);
#endif /* CONFIG_BOOTCOUNT_LIMIT */

	s = getenv ("bootdelay");
	bootdelay = s ? (int)simple_strtol(s, NULL, 10) : CONFIG_BOOTDELAY;

#ifdef CONFIG_OF_CONTROL
	bootdelay = fdtdec_get_config_int(gd->fdt_blob, "bootdelay",
			bootdelay);
#endif

	debug ("### main_loop entered: bootdelay=%d\n\n", bootdelay);

#if defined(CONFIG_MENU_SHOW)
	bootdelay = menu_show(bootdelay);
#endif
# ifdef CONFIG_BOOT_RETRY_TIME
	init_cmd_timeout ();
# endif	/* CONFIG_BOOT_RETRY_TIME */

#ifdef CONFIG_POST
	if (gd->flags & GD_FLG_POSTFAIL) {
		s = getenv("failbootcmd");
	}
	else
#endif /* CONFIG_POST */
#ifdef CONFIG_BOOTCOUNT_LIMIT
	if (bootlimit && (bootcount > bootlimit)) {
		printf ("Warning: Bootlimit (%u) exceeded. Using altbootcmd.\n",
			(unsigned)bootlimit);
		s = getenv ("altbootcmd");
	}
	else
#endif /* CONFIG_BOOTCOUNT_LIMIT */
		s = getenv ("bootcmd");
#ifdef CONFIG_OF_CONTROL
	/* Allow the fdt to override the boot command */
	env = fdtdec_get_config_string(gd->fdt_blob, "bootcmd");
	if (env)
		s = env;

	process_fdt_options(gd->fdt_blob);

	/*
	 * If the bootsecure option was chosen, use secure_boot_cmd().
	 * Always use 'env' in this case, since bootsecure requres that the
	 * bootcmd was specified in the FDT too.
	 */
	if (fdtdec_get_config_int(gd->fdt_blob, "bootsecure", 0))
		secure_boot_cmd(env);

#endif /* CONFIG_OF_CONTROL */

	debug ("### main_loop: bootcmd=\"%s\"\n", s ? s : "<UNDEFINED>");

	if (bootdelay != -1 && s && !abortboot(bootdelay)) {
#if defined(CONFIG_AUTOBOOT_KEYED) && !defined(CONFIG_AUTOBOOT_KEYED_CTRLC)
		int prev = disable_ctrlc(1);	/* disable Control C checking */
#endif

		run_command_list(s, -1, 0);

#if defined(CONFIG_AUTOBOOT_KEYED) && !defined(CONFIG_AUTOBOOT_KEYED_CTRLC)
		disable_ctrlc(prev);	/* restore Control C checking */
#endif
	}

#ifdef CONFIG_MENUKEY
	if (menukey == CONFIG_MENUKEY) {
		s = getenv("menucmd");
		if (s)
			run_command_list(s, -1, 0);
	}
#endif /* CONFIG_MENUKEY */
}
#endif /* CONFIG_BOOTDELAY */

void main_loop(void)
{
#ifdef CONFIG_PREBOOT
	char *p;
#endif

	bootstage_mark_name(BOOTSTAGE_ID_MAIN_LOOP, "main_loop");

#ifndef CONFIG_SYS_GENERIC_BOARD
	puts("Warning: Your board does not use generic board. Please read\n");
	puts("doc/README.generic-board and take action. Boards not\n");
	puts("upgraded by the late 2014 may break or be removed.\n");
#endif

#ifdef CONFIG_MODEM_SUPPORT
	debug("DEBUG: main_loop:   do_mdm_init=%d\n", do_mdm_init);
	if (do_mdm_init) {
		char *str = strdup(getenv("mdm_cmd"));
		setenv("preboot", str);  /* set or delete definition */
		if (str != NULL)
			free(str);
		mdm_init(); /* wait for modem connection */
	}
#endif  /* CONFIG_MODEM_SUPPORT */

#ifdef CONFIG_VERSION_VARIABLE
	{
		setenv("ver", version_string);  /* set version variable */
	}
#endif /* CONFIG_VERSION_VARIABLE */

#ifdef CONFIG_SYS_HUSH_PARSER
	u_boot_hush_start();
#endif

#if defined(CONFIG_HUSH_INIT_VAR)
	hush_init_var();
#endif

#ifdef CONFIG_PREBOOT
	p = getenv("preboot");
	if (p != NULL) {
# ifdef CONFIG_AUTOBOOT_KEYED
		int prev = disable_ctrlc(1);	/* disable Control C checking */
# endif

		run_command_list(p, -1, 0);

# ifdef CONFIG_AUTOBOOT_KEYED
		disable_ctrlc(prev);	/* restore Control C checking */
# endif
	}
#endif /* CONFIG_PREBOOT */

#if defined(CONFIG_UPDATE_TFTP)
	update_tftp(0UL);
#endif /* CONFIG_UPDATE_TFTP */

#ifdef CONFIG_BOOTDELAY
	process_boot_delay();
#endif
	/*
	 * Main Loop for Monitor Command Processing
	 */
#ifdef CONFIG_SYS_HUSH_PARSER
	parse_file_outer();
	/* This point is never reached */
	for (;;);
#else
	cli_loop();
#endif /*CONFIG_SYS_HUSH_PARSER*/
}

/****************************************************************************/

/*
 * Run a command using the selected parser.
 *
 * @param cmd	Command to run
 * @param flag	Execution flags (CMD_FLAG_...)
 * @return 0 on success, or != 0 on error.
 */
int run_command(const char *cmd, int flag)
{
#ifndef CONFIG_SYS_HUSH_PARSER
	/*
	 * cli_run_command can return 0 or 1 for success, so clean up
	 * its result.
	 */
	if (cli_simple_run_command(cmd, flag) == -1)
		return 1;

	return 0;
#else
	return parse_string_outer(cmd,
			FLAG_PARSE_SEMICOLON | FLAG_EXIT_FROM_LOOP);
#endif
}

int run_command_list(const char *cmd, int len, int flag)
{
	int need_buff = 1;
	char *buff = (char *)cmd;	/* cast away const */
	int rcode = 0;

	if (len == -1) {
		len = strlen(cmd);
#ifdef CONFIG_SYS_HUSH_PARSER
		/* hush will never change our string */
		need_buff = 0;
#else
		/* the built-in parser will change our string if it sees \n */
		need_buff = strchr(cmd, '\n') != NULL;
#endif
	}
	if (need_buff) {
		buff = malloc(len + 1);
		if (!buff)
			return 1;
		memcpy(buff, cmd, len);
		buff[len] = '\0';
	}
#ifdef CONFIG_SYS_HUSH_PARSER
	rcode = parse_string_outer(buff, FLAG_PARSE_SEMICOLON);
#else
	/*
	 * This function will overwrite any \n it sees with a \0, which
	 * is why it can't work with a const char *. Here we are making
	 * using of internal knowledge of this function, to avoid always
	 * doing a malloc() which is actually required only in a case that
	 * is pretty rare.
	 */
	rcode = cli_simple_run_command_list(buff, flag);
	if (need_buff)
		free(buff);
#endif

	return rcode;
}

/****************************************************************************/

#if defined(CONFIG_CMD_RUN)
int do_run (cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
{
	int i;

	if (argc < 2)
		return CMD_RET_USAGE;

	for (i=1; i<argc; ++i) {
		char *arg;

		if ((arg = getenv (argv[i])) == NULL) {
			printf ("## Error: \"%s\" not defined\n", argv[i]);
			return 1;
		}

		if (run_command_list(arg, -1, flag) != 0)
			return 1;
	}
	return 0;
}
#endif