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/crc64.c | 114 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 grub-core/lib/crc64.c (limited to 'grub-core/lib/crc64.c') diff --git a/grub-core/lib/crc64.c b/grub-core/lib/crc64.c new file mode 100644 index 0000000..4960f3f --- /dev/null +++ b/grub-core/lib/crc64.c @@ -0,0 +1,114 @@ +/* crc64.c - crc64 function */ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2008,2011 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 + +GRUB_MOD_LICENSE ("GPLv3+"); + +static grub_uint64_t crc64_table [256]; + +/* Helper for init_crc64_table. */ +static grub_uint64_t +reflect (grub_uint64_t ref, int len) +{ + grub_uint64_t result = 0; + int i; + + for (i = 1; i <= len; i++) + { + if (ref & 1) + result |= 1ULL << (len - i); + ref >>= 1; + } + + return result; +} + +static void +init_crc64_table (void) +{ + grub_uint64_t polynomial = 0x42f0e1eba9ea3693ULL; + int i, j; + + for(i = 0; i < 256; i++) + { + crc64_table[i] = reflect(i, 8) << 56; + for (j = 0; j < 8; j++) + { + crc64_table[i] = (crc64_table[i] << 1) ^ + (crc64_table[i] & (1ULL << 63) ? polynomial : 0); + } + crc64_table[i] = reflect(crc64_table[i], 64); + } +} + +static void +crc64_init (void *context) +{ + if (! crc64_table[1]) + init_crc64_table (); + *(grub_uint64_t *) context = 0; +} + +static void +crc64_write (void *context, const void *buf, grub_size_t size) +{ + unsigned i; + const grub_uint8_t *data = buf; + grub_uint64_t crc = ~grub_le_to_cpu64 (*(grub_uint64_t *) context); + + for (i = 0; i < size; i++) + { + crc = (crc >> 8) ^ crc64_table[(crc & 0xFF) ^ *data]; + data++; + } + + *(grub_uint64_t *) context = grub_cpu_to_le64 (~crc); +} + +static grub_uint8_t * +crc64_read (void *context) +{ + return context; +} + +static void +crc64_final (void *context __attribute__ ((unused))) +{ +} + +gcry_md_spec_t _gcry_digest_spec_crc64 = + { + "CRC64", 0, 0, 0, 8, + crc64_init, crc64_write, crc64_final, crc64_read, + sizeof (grub_uint64_t), + .blocksize = 64 + }; + +GRUB_MOD_INIT(crc64) +{ + grub_md_register (&_gcry_digest_spec_crc64); +} + +GRUB_MOD_FINI(crc64) +{ + grub_md_unregister (&_gcry_digest_spec_crc64); +} -- cgit v1.2.3