From 6e7a315eb67cb6c113cf37e1d66c4f11a51a2b3e Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 18:29:51 +0200 Subject: Adding upstream version 2.06. Signed-off-by: Daniel Baumann --- grub-core/lib/random.c | 120 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 120 insertions(+) create mode 100644 grub-core/lib/random.c (limited to 'grub-core/lib/random.c') diff --git a/grub-core/lib/random.c b/grub-core/lib/random.c new file mode 100644 index 0000000..43b9664 --- /dev/null +++ b/grub-core/lib/random.c @@ -0,0 +1,120 @@ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2016 Free Software Foundation, Inc. + * + * GRUB is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * GRUB is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GRUB. If not, see . + */ + +#include +#include +#include +#include +#include + +GRUB_MOD_LICENSE ("GPLv3+"); + +grub_err_t +grub_crypto_get_random (void *buffer, grub_size_t sz) +{ + /* This is an arbitrer between different methods. + TODO: Add more methods in the future. */ + /* TODO: Add some PRNG smartness to reduce damage from bad entropy. */ + if (grub_crypto_arch_get_random (buffer, sz)) + return GRUB_ERR_NONE; + return grub_error (GRUB_ERR_IO, "no random sources found"); +} + +static int +get_num_digits (int val) +{ + int ret = 0; + while (val != 0) + { + ret++; + val /= 10; + } + if (ret == 0) + return 1; + return ret; +} + +#pragma GCC diagnostic ignored "-Wformat-nonliteral" + +static grub_err_t +grub_cmd_hexdump_random (grub_command_t cmd __attribute__ ((unused)), int argc, char **args) +{ + grub_size_t length = 64; + grub_err_t err; + void *buffer; + grub_uint8_t *ptr; + int stats[256]; + int i, digits = 2; + char template[10]; + + if (argc >= 1) + length = grub_strtoull (args[0], 0, 0); + + if (length == 0) + return grub_error (GRUB_ERR_BAD_ARGUMENT, "length pust be positive"); + + buffer = grub_malloc (length); + if (!buffer) + return grub_errno; + + err = grub_crypto_get_random (buffer, length); + if (err) + { + grub_free (buffer); + return err; + } + + hexdump (0, buffer, length); + grub_memset(stats, 0, sizeof(stats)); + for (ptr = buffer; ptr < (grub_uint8_t *) buffer + length; ptr++) + stats[*ptr]++; + grub_printf ("Statistics:\n"); + for (i = 0; i < 256; i++) + { + int z = get_num_digits (stats[i]); + if (z > digits) + digits = z; + } + + grub_snprintf (template, sizeof (template), "%%0%dd ", digits); + + for (i = 0; i < 256; i++) + { + grub_printf ("%s", template);//, stats[i]); + if ((i & 0xf) == 0xf) + grub_printf ("\n"); + } + + grub_free (buffer); + + return 0; +} + +static grub_command_t cmd; + +GRUB_MOD_INIT (random) +{ + cmd = grub_register_command ("hexdump_random", grub_cmd_hexdump_random, + N_("[LENGTH]"), + N_("Hexdump random data.")); +} + +GRUB_MOD_FINI (random) +{ + grub_unregister_command (cmd); +} -- cgit v1.2.3