common/cli.c

   1 /*
   2  * (C) Copyright 2000
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * Add to readline cmdline-editing by
   6  * (C) Copyright 2005
   7  * JinHua Luo, GuangDong Linux Center, <luo.jinhua@gd-linux.com>
   8  *
   9  * SPDX-License-Identifier:     GPL-2.0+
  10  */
  11
  12 #include <common.h>
  13 #include <cli.h>
  14 #include <cli_hush.h>
  15 #include <console.h>
  16 #include <fdtdec.h>
  17 #include <malloc.h>
  18
  19 DECLARE_GLOBAL_DATA_PTR;
  20
  21 /*
  22  * Run a command using the selected parser.
  23  *
  24  * @param cmd   Command to run
  25  * @param flag  Execution flags (CMD_FLAG_...)
  26  * @return 0 on success, or != 0 on error.
  27  */
  28 int run_command(const char *cmd, int flag)
  29 {
  30 #ifndef CONFIG_SYS_HUSH_PARSER
  31         /*
  32          * cli_run_command can return 0 or 1 for success, so clean up
  33          * its result.
  34          */
  35         if (cli_simple_run_command(cmd, flag) == -1)
  36                 return 1;
  37
  38         return 0;
  39 #else
  40         int hush_flags = FLAG_PARSE_SEMICOLON | FLAG_EXIT_FROM_LOOP;
  41
  42         if (flag & CMD_FLAG_ENV)
  43                 hush_flags |= FLAG_CONT_ON_NEWLINE;
  44         return parse_string_outer(cmd, hush_flags);
  45 #endif
  46 }
  47
  48 /*
  49  * Run a command using the selected parser, and check if it is repeatable.
  50  *
  51  * @param cmd   Command to run
  52  * @param flag  Execution flags (CMD_FLAG_...)
  53  * @return 0 (not repeatable) or 1 (repeatable) on success, -1 on error.
  54  */
  55 int run_command_repeatable(const char *cmd, int flag)
  56 {
  57 #ifndef CONFIG_SYS_HUSH_PARSER
  58         return cli_simple_run_command(cmd, flag);
  59 #else
  60         /*
  61          * parse_string_outer() returns 1 for failure, so clean up
  62          * its result.
  63          */
  64         if (parse_string_outer(cmd,
  65                                FLAG_PARSE_SEMICOLON | FLAG_EXIT_FROM_LOOP))
  66                 return -1;
  67
  68         return 0;
  69 #endif
  70 }
  71
  72 int run_command_list(const char *cmd, int len, int flag)
  73 {
  74         int need_buff = 1;
  75         char *buff = (char *)cmd;       /* cast away const */
  76         int rcode = 0;
  77
  78         if (len == -1) {
  79                 len = strlen(cmd);
  80 #ifdef CONFIG_SYS_HUSH_PARSER
  81                 /* hush will never change our string */
  82                 need_buff = 0;
  83 #else
  84                 /* the built-in parser will change our string if it sees \n */
  85                 need_buff = strchr(cmd, '\n') != NULL;
  86 #endif
  87         }
  88         if (need_buff) {
  89                 buff = malloc(len + 1);
  90                 if (!buff)
  91                         return 1;
  92                 memcpy(buff, cmd, len);
  93                 buff[len] = '\0';
  94         }
  95 #ifdef CONFIG_SYS_HUSH_PARSER
  96         rcode = parse_string_outer(buff, FLAG_PARSE_SEMICOLON);
  97 #else
  98         /*
  99          * This function will overwrite any \n it sees with a \0, which
 100          * is why it can't work with a const char *. Here we are making
 101          * using of internal knowledge of this function, to avoid always
 102          * doing a malloc() which is actually required only in a case that
 103          * is pretty rare.
 104          */
 105         rcode = cli_simple_run_command_list(buff, flag);
 106 #endif
 107         if (need_buff)
 108                 free(buff);
 109
 110         return rcode;
 111 }
 112
 113 /****************************************************************************/
 114
 115 #if defined(CONFIG_CMD_RUN)
 116 int do_run(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 117 {
 118         int i;
 119
 120         if (argc < 2)
 121                 return CMD_RET_USAGE;
 122
 123         for (i = 1; i < argc; ++i) {
 124                 char *arg;
 125
 126                 arg = getenv(argv[i]);
 127                 if (arg == NULL) {
 128                         printf("## Error: \"%s\" not defined\n", argv[i]);
 129                         return 1;
 130                 }
 131
 132                 if (run_command(arg, flag | CMD_FLAG_ENV) != 0)
 133                         return 1;
 134         }
 135         return 0;
 136 }
 137 #endif
 138
 139 #if CONFIG_IS_ENABLED(OF_CONTROL)
 140 bool cli_process_fdt(const char **cmdp)
 141 {
 142         /* Allow the fdt to override the boot command */
 143         char *env = fdtdec_get_config_string(gd->fdt_blob, "bootcmd");
 144         if (env)
 145                 *cmdp = env;
 146         /*
 147          * If the bootsecure option was chosen, use secure_boot_cmd().
 148          * Always use 'env' in this case, since bootsecure requres that the
 149          * bootcmd was specified in the FDT too.
 150          */
 151         return fdtdec_get_config_int(gd->fdt_blob, "bootsecure", 0) != 0;
 152 }
 153
 154 /*
 155  * Runs the given boot command securely.  Specifically:
 156  * - Doesn't run the command with the shell (run_command or parse_string_outer),
 157  *   since that's a lot of code surface that an attacker might exploit.
 158  *   Because of this, we don't do any argument parsing--the secure boot command
 159  *   has to be a full-fledged u-boot command.
 160  * - Doesn't check for keypresses before booting, since that could be a
 161  *   security hole; also disables Ctrl-C.
 162  * - Doesn't allow the command to return.
 163  *
 164  * Upon any failures, this function will drop into an infinite loop after
 165  * printing the error message to console.
 166  */
 167 void cli_secure_boot_cmd(const char *cmd)
 168 {
 169         cmd_tbl_t *cmdtp;
 170         int rc;
 171
 172         if (!cmd) {
 173                 printf("## Error: Secure boot command not specified\n");
 174                 goto err;
 175         }
 176
 177         /* Disable Ctrl-C just in case some command is used that checks it. */
 178         disable_ctrlc(1);
 179
 180         /* Find the command directly. */
 181         cmdtp = find_cmd(cmd);
 182         if (!cmdtp) {
 183                 printf("## Error: \"%s\" not defined\n", cmd);
 184                 goto err;
 185         }
 186
 187         /* Run the command, forcing no flags and faking argc and argv. */
 188         rc = (cmdtp->cmd)(cmdtp, 0, 1, (char **)&cmd);
 189
 190         /* Shouldn't ever return from boot command. */
 191         printf("## Error: \"%s\" returned (code %d)\n", cmd, rc);
 192
 193 err:
 194         /*
 195          * Not a whole lot to do here.  Rebooting won't help much, since we'll
 196          * just end up right back here.  Just loop.
 197          */
 198         hang();
 199 }
 200 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
 201
 202 void cli_loop(void)
 203 {
 204 #ifdef CONFIG_SYS_HUSH_PARSER
 205         parse_file_outer();
 206         /* This point is never reached */
 207         for (;;);
 208 #else
 209         cli_simple_loop();
 210 #endif /*CONFIG_SYS_HUSH_PARSER*/
 211 }
 212
 213 void cli_init(void)
 214 {
 215 #ifdef CONFIG_SYS_HUSH_PARSER
 216         u_boot_hush_start();
 217 #endif
 218
 219 #if defined(CONFIG_HUSH_INIT_VAR)
 220         hush_init_var();
 221 #endif
 222 }