common/cli.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * (C) Copyright 2000
   4  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   5  *
   6  * Add to readline cmdline-editing by
   7  * (C) Copyright 2005
   8  * JinHua Luo, GuangDong Linux Center, <luo.jinhua@gd-linux.com>
   9  */
  10
  11 #include <common.h>
  12 #include <bootstage.h>
  13 #include <cli.h>
  14 #include <cli_hush.h>
  15 #include <command.h>
  16 #include <console.h>
  17 #include <env.h>
  18 #include <fdtdec.h>
  19 #include <hang.h>
  20 #include <malloc.h>
  21
  22 DECLARE_GLOBAL_DATA_PTR;
  23
  24 #ifdef CONFIG_CMDLINE
  25 /*
  26  * Run a command using the selected parser.
  27  *
  28  * @param cmd   Command to run
  29  * @param flag  Execution flags (CMD_FLAG_...)
  30  * @return 0 on success, or != 0 on error.
  31  */
  32 int run_command(const char *cmd, int flag)
  33 {
  34 #if !CONFIG_IS_ENABLED(HUSH_PARSER)
  35         /*
  36          * cli_run_command can return 0 or 1 for success, so clean up
  37          * its result.
  38          */
  39         if (cli_simple_run_command(cmd, flag) == -1)
  40                 return 1;
  41
  42         return 0;
  43 #else
  44         int hush_flags = FLAG_PARSE_SEMICOLON | FLAG_EXIT_FROM_LOOP;
  45
  46         if (flag & CMD_FLAG_ENV)
  47                 hush_flags |= FLAG_CONT_ON_NEWLINE;
  48         return parse_string_outer(cmd, hush_flags);
  49 #endif
  50 }
  51
  52 /*
  53  * Run a command using the selected parser, and check if it is repeatable.
  54  *
  55  * @param cmd   Command to run
  56  * @param flag  Execution flags (CMD_FLAG_...)
  57  * @return 0 (not repeatable) or 1 (repeatable) on success, -1 on error.
  58  */
  59 int run_command_repeatable(const char *cmd, int flag)
  60 {
  61 #ifndef CONFIG_HUSH_PARSER
  62         return cli_simple_run_command(cmd, flag);
  63 #else
  64         /*
  65          * parse_string_outer() returns 1 for failure, so clean up
  66          * its result.
  67          */
  68         if (parse_string_outer(cmd,
  69                                FLAG_PARSE_SEMICOLON | FLAG_EXIT_FROM_LOOP))
  70                 return -1;
  71
  72         return 0;
  73 #endif
  74 }
  75 #else
  76 __weak int board_run_command(const char *cmdline)
  77 {
  78         printf("## Commands are disabled. Please enable CONFIG_CMDLINE.\n");
  79
  80         return 1;
  81 }
  82 #endif /* CONFIG_CMDLINE */
  83
  84 int run_command_list(const char *cmd, int len, int flag)
  85 {
  86         int need_buff = 1;
  87         char *buff = (char *)cmd;       /* cast away const */
  88         int rcode = 0;
  89
  90         if (len == -1) {
  91                 len = strlen(cmd);
  92 #ifdef CONFIG_HUSH_PARSER
  93                 /* hush will never change our string */
  94                 need_buff = 0;
  95 #else
  96                 /* the built-in parser will change our string if it sees \n */
  97                 need_buff = strchr(cmd, '\n') != NULL;
  98 #endif
  99         }
 100         if (need_buff) {
 101                 buff = malloc(len + 1);
 102                 if (!buff)
 103                         return 1;
 104                 memcpy(buff, cmd, len);
 105                 buff[len] = '\0';
 106         }
 107 #ifdef CONFIG_HUSH_PARSER
 108         rcode = parse_string_outer(buff, FLAG_PARSE_SEMICOLON);
 109 #else
 110         /*
 111          * This function will overwrite any \n it sees with a \0, which
 112          * is why it can't work with a const char *. Here we are making
 113          * using of internal knowledge of this function, to avoid always
 114          * doing a malloc() which is actually required only in a case that
 115          * is pretty rare.
 116          */
 117 #ifdef CONFIG_CMDLINE
 118         rcode = cli_simple_run_command_list(buff, flag);
 119 #else
 120         rcode = board_run_command(buff);
 121 #endif
 122 #endif
 123         if (need_buff)
 124                 free(buff);
 125
 126         return rcode;
 127 }
 128
 129 /****************************************************************************/
 130
 131 #if defined(CONFIG_CMD_RUN)
 132 int do_run(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
 133 {
 134         int i;
 135
 136         if (argc < 2)
 137                 return CMD_RET_USAGE;
 138
 139         for (i = 1; i < argc; ++i) {
 140                 char *arg;
 141
 142                 arg = env_get(argv[i]);
 143                 if (arg == NULL) {
 144                         printf("## Error: \"%s\" not defined\n", argv[i]);
 145                         return 1;
 146                 }
 147
 148                 if (run_command(arg, flag | CMD_FLAG_ENV) != 0)
 149                         return 1;
 150         }
 151         return 0;
 152 }
 153 #endif
 154
 155 #if CONFIG_IS_ENABLED(OF_CONTROL)
 156 bool cli_process_fdt(const char **cmdp)
 157 {
 158         /* Allow the fdt to override the boot command */
 159         char *env = fdtdec_get_config_string(gd->fdt_blob, "bootcmd");
 160         if (env)
 161                 *cmdp = env;
 162         /*
 163          * If the bootsecure option was chosen, use secure_boot_cmd().
 164          * Always use 'env' in this case, since bootsecure requres that the
 165          * bootcmd was specified in the FDT too.
 166          */
 167         return fdtdec_get_config_int(gd->fdt_blob, "bootsecure", 0) != 0;
 168 }
 169
 170 /*
 171  * Runs the given boot command securely.  Specifically:
 172  * - Doesn't run the command with the shell (run_command or parse_string_outer),
 173  *   since that's a lot of code surface that an attacker might exploit.
 174  *   Because of this, we don't do any argument parsing--the secure boot command
 175  *   has to be a full-fledged u-boot command.
 176  * - Doesn't check for keypresses before booting, since that could be a
 177  *   security hole; also disables Ctrl-C.
 178  * - Doesn't allow the command to return.
 179  *
 180  * Upon any failures, this function will drop into an infinite loop after
 181  * printing the error message to console.
 182  */
 183 void cli_secure_boot_cmd(const char *cmd)
 184 {
 185 #ifdef CONFIG_CMDLINE
 186         struct cmd_tbl *cmdtp;
 187 #endif
 188         int rc;
 189
 190         if (!cmd) {
 191                 printf("## Error: Secure boot command not specified\n");
 192                 goto err;
 193         }
 194
 195         /* Disable Ctrl-C just in case some command is used that checks it. */
 196         disable_ctrlc(1);
 197
 198         /* Find the command directly. */
 199 #ifdef CONFIG_CMDLINE
 200         cmdtp = find_cmd(cmd);
 201         if (!cmdtp) {
 202                 printf("## Error: \"%s\" not defined\n", cmd);
 203                 goto err;
 204         }
 205
 206         /* Run the command, forcing no flags and faking argc and argv. */
 207         rc = (cmdtp->cmd)(cmdtp, 0, 1, (char **)&cmd);
 208
 209 #else
 210         rc = board_run_command(cmd);
 211 #endif
 212
 213         /* Shouldn't ever return from boot command. */
 214         printf("## Error: \"%s\" returned (code %d)\n", cmd, rc);
 215
 216 err:
 217         /*
 218          * Not a whole lot to do here.  Rebooting won't help much, since we'll
 219          * just end up right back here.  Just loop.
 220          */
 221         hang();
 222 }
 223 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
 224
 225 void cli_loop(void)
 226 {
 227         bootstage_mark(BOOTSTAGE_ID_ENTER_CLI_LOOP);
 228 #ifdef CONFIG_HUSH_PARSER
 229         parse_file_outer();
 230         /* This point is never reached */
 231         for (;;);
 232 #elif defined(CONFIG_CMDLINE)
 233         cli_simple_loop();
 234 #else
 235         printf("## U-Boot command line is disabled. Please enable CONFIG_CMDLINE\n");
 236 #endif /*CONFIG_HUSH_PARSER*/
 237 }
 238
 239 void cli_init(void)
 240 {
 241 #ifdef CONFIG_HUSH_PARSER
 242         u_boot_hush_start();
 243 #endif
 244
 245 #if defined(CONFIG_HUSH_INIT_VAR)
 246         hush_init_var();
 247 #endif
 248 }