xref: /openbmc/u-boot/common/cli.c (revision affb215626f91e717088a27081d24c473895d47d)
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 int run_command_list(const char *cmd, int len, int flag)
45 {
46 	int need_buff = 1;
47 	char *buff = (char *)cmd;	/* cast away const */
48 	int rcode = 0;
49 
50 	if (len == -1) {
51 		len = strlen(cmd);
52 #ifdef CONFIG_SYS_HUSH_PARSER
53 		/* hush will never change our string */
54 		need_buff = 0;
55 #else
56 		/* the built-in parser will change our string if it sees \n */
57 		need_buff = strchr(cmd, '\n') != NULL;
58 #endif
59 	}
60 	if (need_buff) {
61 		buff = malloc(len + 1);
62 		if (!buff)
63 			return 1;
64 		memcpy(buff, cmd, len);
65 		buff[len] = '\0';
66 	}
67 #ifdef CONFIG_SYS_HUSH_PARSER
68 	rcode = parse_string_outer(buff, FLAG_PARSE_SEMICOLON);
69 #else
70 	/*
71 	 * This function will overwrite any \n it sees with a \0, which
72 	 * is why it can't work with a const char *. Here we are making
73 	 * using of internal knowledge of this function, to avoid always
74 	 * doing a malloc() which is actually required only in a case that
75 	 * is pretty rare.
76 	 */
77 	rcode = cli_simple_run_command_list(buff, flag);
78 	if (need_buff)
79 		free(buff);
80 #endif
81 
82 	return rcode;
83 }
84 
85 /****************************************************************************/
86 
87 #if defined(CONFIG_CMD_RUN)
88 int do_run(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
89 {
90 	int i;
91 
92 	if (argc < 2)
93 		return CMD_RET_USAGE;
94 
95 	for (i = 1; i < argc; ++i) {
96 		char *arg;
97 
98 		arg = getenv(argv[i]);
99 		if (arg == NULL) {
100 			printf("## Error: \"%s\" not defined\n", argv[i]);
101 			return 1;
102 		}
103 
104 		if (run_command(arg, flag) != 0)
105 			return 1;
106 	}
107 	return 0;
108 }
109 #endif
110 
111 #ifdef CONFIG_OF_CONTROL
112 bool cli_process_fdt(const char **cmdp)
113 {
114 	/* Allow the fdt to override the boot command */
115 	char *env = fdtdec_get_config_string(gd->fdt_blob, "bootcmd");
116 	if (env)
117 		*cmdp = env;
118 	/*
119 	 * If the bootsecure option was chosen, use secure_boot_cmd().
120 	 * Always use 'env' in this case, since bootsecure requres that the
121 	 * bootcmd was specified in the FDT too.
122 	 */
123 	return fdtdec_get_config_int(gd->fdt_blob, "bootsecure", 0) != 0;
124 }
125 
126 /*
127  * Runs the given boot command securely.  Specifically:
128  * - Doesn't run the command with the shell (run_command or parse_string_outer),
129  *   since that's a lot of code surface that an attacker might exploit.
130  *   Because of this, we don't do any argument parsing--the secure boot command
131  *   has to be a full-fledged u-boot command.
132  * - Doesn't check for keypresses before booting, since that could be a
133  *   security hole; also disables Ctrl-C.
134  * - Doesn't allow the command to return.
135  *
136  * Upon any failures, this function will drop into an infinite loop after
137  * printing the error message to console.
138  */
139 void cli_secure_boot_cmd(const char *cmd)
140 {
141 	cmd_tbl_t *cmdtp;
142 	int rc;
143 
144 	if (!cmd) {
145 		printf("## Error: Secure boot command not specified\n");
146 		goto err;
147 	}
148 
149 	/* Disable Ctrl-C just in case some command is used that checks it. */
150 	disable_ctrlc(1);
151 
152 	/* Find the command directly. */
153 	cmdtp = find_cmd(cmd);
154 	if (!cmdtp) {
155 		printf("## Error: \"%s\" not defined\n", cmd);
156 		goto err;
157 	}
158 
159 	/* Run the command, forcing no flags and faking argc and argv. */
160 	rc = (cmdtp->cmd)(cmdtp, 0, 1, (char **)&cmd);
161 
162 	/* Shouldn't ever return from boot command. */
163 	printf("## Error: \"%s\" returned (code %d)\n", cmd, rc);
164 
165 err:
166 	/*
167 	 * Not a whole lot to do here.  Rebooting won't help much, since we'll
168 	 * just end up right back here.  Just loop.
169 	 */
170 	hang();
171 }
172 #endif /* CONFIG_OF_CONTROL */
173 
174 void cli_loop(void)
175 {
176 #ifdef CONFIG_SYS_HUSH_PARSER
177 	parse_file_outer();
178 	/* This point is never reached */
179 	for (;;);
180 #else
181 	cli_simple_loop();
182 #endif /*CONFIG_SYS_HUSH_PARSER*/
183 }
184 
185 void cli_init(void)
186 {
187 #ifdef CONFIG_SYS_HUSH_PARSER
188 	u_boot_hush_start();
189 #endif
190 
191 #if defined(CONFIG_HUSH_INIT_VAR)
192 	hush_init_var();
193 #endif
194 }
195