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 #include <asm/global_data.h>
22 
23 DECLARE_GLOBAL_DATA_PTR;
24 
25 #ifdef CONFIG_CMDLINE
26 /*
27  * Run a command using the selected parser.
28  *
29  * @param cmd	Command to run
30  * @param flag	Execution flags (CMD_FLAG_...)
31  * @return 0 on success, or != 0 on error.
32  */
run_command(const char * cmd,int flag)33 int run_command(const char *cmd, int flag)
34 {
35 #if !CONFIG_IS_ENABLED(HUSH_PARSER)
36 	/*
37 	 * cli_run_command can return 0 or 1 for success, so clean up
38 	 * its result.
39 	 */
40 	if (cli_simple_run_command(cmd, flag) == -1)
41 		return 1;
42 
43 	return 0;
44 #else
45 	int hush_flags = FLAG_PARSE_SEMICOLON | FLAG_EXIT_FROM_LOOP;
46 
47 	if (flag & CMD_FLAG_ENV)
48 		hush_flags |= FLAG_CONT_ON_NEWLINE;
49 	return parse_string_outer(cmd, hush_flags);
50 #endif
51 }
52 
53 /*
54  * Run a command using the selected parser, and check if it is repeatable.
55  *
56  * @param cmd	Command to run
57  * @param flag	Execution flags (CMD_FLAG_...)
58  * @return 0 (not repeatable) or 1 (repeatable) on success, -1 on error.
59  */
run_command_repeatable(const char * cmd,int flag)60 int run_command_repeatable(const char *cmd, int flag)
61 {
62 #ifndef CONFIG_HUSH_PARSER
63 	return cli_simple_run_command(cmd, flag);
64 #else
65 	/*
66 	 * parse_string_outer() returns 1 for failure, so clean up
67 	 * its result.
68 	 */
69 	if (parse_string_outer(cmd,
70 			       FLAG_PARSE_SEMICOLON | FLAG_EXIT_FROM_LOOP))
71 		return -1;
72 
73 	return 0;
74 #endif
75 }
76 #else
board_run_command(const char * cmdline)77 __weak int board_run_command(const char *cmdline)
78 {
79 	printf("## Commands are disabled. Please enable CONFIG_CMDLINE.\n");
80 
81 	return 1;
82 }
83 #endif /* CONFIG_CMDLINE */
84 
run_command_list(const char * cmd,int len,int flag)85 int run_command_list(const char *cmd, int len, int flag)
86 {
87 	int need_buff = 1;
88 	char *buff = (char *)cmd;	/* cast away const */
89 	int rcode = 0;
90 
91 	if (len == -1) {
92 		len = strlen(cmd);
93 #ifdef CONFIG_HUSH_PARSER
94 		/* hush will never change our string */
95 		need_buff = 0;
96 #else
97 		/* the built-in parser will change our string if it sees \n */
98 		need_buff = strchr(cmd, '\n') != NULL;
99 #endif
100 	}
101 	if (need_buff) {
102 		buff = malloc(len + 1);
103 		if (!buff)
104 			return 1;
105 		memcpy(buff, cmd, len);
106 		buff[len] = '\0';
107 	}
108 #ifdef CONFIG_HUSH_PARSER
109 	rcode = parse_string_outer(buff, FLAG_PARSE_SEMICOLON);
110 #else
111 	/*
112 	 * This function will overwrite any \n it sees with a \0, which
113 	 * is why it can't work with a const char *. Here we are making
114 	 * using of internal knowledge of this function, to avoid always
115 	 * doing a malloc() which is actually required only in a case that
116 	 * is pretty rare.
117 	 */
118 #ifdef CONFIG_CMDLINE
119 	rcode = cli_simple_run_command_list(buff, flag);
120 #else
121 	rcode = board_run_command(buff);
122 #endif
123 #endif
124 	if (need_buff)
125 		free(buff);
126 
127 	return rcode;
128 }
129 
130 /****************************************************************************/
131 
132 #if defined(CONFIG_CMD_RUN)
do_run(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])133 int do_run(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
134 {
135 	int i;
136 
137 	if (argc < 2)
138 		return CMD_RET_USAGE;
139 
140 	for (i = 1; i < argc; ++i) {
141 		char *arg;
142 
143 		arg = env_get(argv[i]);
144 		if (arg == NULL) {
145 			printf("## Error: \"%s\" not defined\n", argv[i]);
146 			return 1;
147 		}
148 
149 		if (run_command(arg, flag | CMD_FLAG_ENV) != 0)
150 			return 1;
151 	}
152 	return 0;
153 }
154 #endif
155 
156 #if CONFIG_IS_ENABLED(OF_CONTROL)
cli_process_fdt(const char ** cmdp)157 bool cli_process_fdt(const char **cmdp)
158 {
159 	/* Allow the fdt to override the boot command */
160 	char *env = fdtdec_get_config_string(gd->fdt_blob, "bootcmd");
161 	if (env)
162 		*cmdp = env;
163 	/*
164 	 * If the bootsecure option was chosen, use secure_boot_cmd().
165 	 * Always use 'env' in this case, since bootsecure requres that the
166 	 * bootcmd was specified in the FDT too.
167 	 */
168 	return fdtdec_get_config_int(gd->fdt_blob, "bootsecure", 0) != 0;
169 }
170 
171 /*
172  * Runs the given boot command securely.  Specifically:
173  * - Doesn't run the command with the shell (run_command or parse_string_outer),
174  *   since that's a lot of code surface that an attacker might exploit.
175  *   Because of this, we don't do any argument parsing--the secure boot command
176  *   has to be a full-fledged u-boot command.
177  * - Doesn't check for keypresses before booting, since that could be a
178  *   security hole; also disables Ctrl-C.
179  * - Doesn't allow the command to return.
180  *
181  * Upon any failures, this function will drop into an infinite loop after
182  * printing the error message to console.
183  */
cli_secure_boot_cmd(const char * cmd)184 void cli_secure_boot_cmd(const char *cmd)
185 {
186 #ifdef CONFIG_CMDLINE
187 	struct cmd_tbl *cmdtp;
188 #endif
189 	int rc;
190 
191 	if (!cmd) {
192 		printf("## Error: Secure boot command not specified\n");
193 		goto err;
194 	}
195 
196 	/* Disable Ctrl-C just in case some command is used that checks it. */
197 	disable_ctrlc(1);
198 
199 	/* Find the command directly. */
200 #ifdef CONFIG_CMDLINE
201 	cmdtp = find_cmd(cmd);
202 	if (!cmdtp) {
203 		printf("## Error: \"%s\" not defined\n", cmd);
204 		goto err;
205 	}
206 
207 	/* Run the command, forcing no flags and faking argc and argv. */
208 	rc = (cmdtp->cmd)(cmdtp, 0, 1, (char **)&cmd);
209 
210 #else
211 	rc = board_run_command(cmd);
212 #endif
213 
214 	/* Shouldn't ever return from boot command. */
215 	printf("## Error: \"%s\" returned (code %d)\n", cmd, rc);
216 
217 err:
218 	/*
219 	 * Not a whole lot to do here.  Rebooting won't help much, since we'll
220 	 * just end up right back here.  Just loop.
221 	 */
222 	hang();
223 }
224 #endif /* CONFIG_IS_ENABLED(OF_CONTROL) */
225 
cli_loop(void)226 void cli_loop(void)
227 {
228 	bootstage_mark(BOOTSTAGE_ID_ENTER_CLI_LOOP);
229 #ifdef CONFIG_HUSH_PARSER
230 	parse_file_outer();
231 	/* This point is never reached */
232 	for (;;);
233 #elif defined(CONFIG_CMDLINE)
234 	cli_simple_loop();
235 #else
236 	printf("## U-Boot command line is disabled. Please enable CONFIG_CMDLINE\n");
237 #endif /*CONFIG_HUSH_PARSER*/
238 }
239 
cli_init(void)240 void cli_init(void)
241 {
242 #ifdef CONFIG_HUSH_PARSER
243 	u_boot_hush_start();
244 #endif
245 
246 #if defined(CONFIG_HUSH_INIT_VAR)
247 	hush_init_var();
248 #endif
249 }
250