[J-u-boot.git] / cmd / rng.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * The 'rng' command prints bytes from the hardware random number generator.
 *
 * Copyright (c) 2019, Heinrich Schuchardt <[email protected]>
 */
#include <common.h>
#include <command.h>
#include <dm.h>
#include <hexdump.h>
#include <malloc.h>
#include <rng.h>

static int do_rng(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
{
	size_t n = 0x40;
	struct udevice *dev;
	void *buf;
	int ret = CMD_RET_SUCCESS;

	if (uclass_get_device(UCLASS_RNG, 0, &dev) || !dev) {
		printf("No RNG device\n");
		return CMD_RET_FAILURE;
	}

	if (argc >= 2)
		n = simple_strtoul(argv[1], NULL, 16);

	buf = malloc(n);
	if (!buf) {
		printf("Out of memory\n");
		return CMD_RET_FAILURE;
	}

	if (dm_rng_read(dev, buf, n)) {
		printf("Reading RNG failed\n");
		ret = CMD_RET_FAILURE;
	} else {
		print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, buf, n);
	}

	free(buf);

	return ret;
}

#ifdef CONFIG_SYS_LONGHELP
static char rng_help_text[] =
	"[n]\n"
	"  - print n random bytes\n";
#endif

U_BOOT_CMD(
	rng, 2, 0, do_rng,
	"print bytes from the hardware random number generator",
	rng_help_text
);
Commit	Line	Data
4f24ac08 HS	1	// SPDX-License-Identifier: GPL-2.0+
	2	/*
	3	* The 'rng' command prints bytes from the hardware random number generator.
	4	*
	5	* Copyright (c) 2019, Heinrich Schuchardt <[email protected]>
	6	*/
	7	#include <common.h>
	8	#include <command.h>
	9	#include <dm.h>
	10	#include <hexdump.h>
336d4615	11	#include <malloc.h>
4f24ac08 HS	12	#include <rng.h>
4f24ac08 HS	13
09140113	14	static int do_rng(struct cmd_tbl cmdtp, int flag, int argc, char const argv[])
4f24ac08 HS	15	{
	16	size_t n = 0x40;
	17	struct udevice *dev;
	18	void *buf;
	19	int ret = CMD_RET_SUCCESS;
	20
	21	if (uclass_get_device(UCLASS_RNG, 0, &dev) \|\| !dev) {
	22	printf("No RNG device\n");
	23	return CMD_RET_FAILURE;
	24	}
	25
	26	if (argc >= 2)
	27	n = simple_strtoul(argv[1], NULL, 16);
	28
	29	buf = malloc(n);
	30	if (!buf) {
	31	printf("Out of memory\n");
	32	return CMD_RET_FAILURE;
	33	}
	34
	35	if (dm_rng_read(dev, buf, n)) {
	36	printf("Reading RNG failed\n");
	37	ret = CMD_RET_FAILURE;
	38	} else {
	39	print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, buf, n);
	40	}
	41
	42	free(buf);
	43
	44	return ret;
	45	}
	46
	47	#ifdef CONFIG_SYS_LONGHELP
	48	static char rng_help_text[] =
	49	"[n]\n"
	50	" - print n random bytes\n";
	51	#endif
	52
	53	U_BOOT_CMD(
	54	rng, 2, 0, do_rng,
	55	"print bytes from the hardware random number generator",
	56	rng_help_text
	57	);