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