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