1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * The 'kaslrseed' command takes bytes from the hardware random number
4 * generator and uses them to set the kaslr-seed value in the chosen node.
5 *
6 * Copyright (c) 2021, Chris Morgan <macromorgan@hotmail.com>
7 */
8
9 #include <command.h>
10 #include <dm.h>
11 #include <hexdump.h>
12 #include <malloc.h>
13 #include <rng.h>
14 #include <fdt_support.h>
15
do_kaslr_seed(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])16 static int do_kaslr_seed(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
17 {
18 int err = CMD_RET_SUCCESS;
19
20 printf("Notice: a /chosen/kaslr-seed is automatically added to the device-tree when booted via booti/bootm/bootz therefore using this command is likely no longer needed\n");
21
22 if (!working_fdt) {
23 printf("No FDT memory address configured. Please configure\n"
24 "the FDT address via \"fdt addr <address>\" command.\n"
25 "Aborting!\n");
26 err = CMD_RET_FAILURE;
27 } else {
28 if (fdt_kaslrseed(working_fdt, true) < 0)
29 err = CMD_RET_FAILURE;
30 }
31
32 return cmd_process_error(cmdtp, err);
33 }
34
35 U_BOOT_LONGHELP(kaslrseed,
36 "\n"
37 " - append random bytes to chosen kaslr-seed node\n");
38
39 U_BOOT_CMD(
40 kaslrseed, 1, 0, do_kaslr_seed,
41 "feed bytes from the hardware random number generator to the kaslr-seed",
42 kaslrseed_help_text
43 );
44