sd-boot: Use UEFI provided CRC32

This commit is contained in:
Jan Janssen 2021-08-17 11:44:21 +02:00 committed by Luca Boccassi
parent 0d341eccef
commit 87167331c9
4 changed files with 10 additions and 170 deletions

View File

@ -5,7 +5,6 @@
#include <efilib.h>
#include "console.h"
#include "crc32.h"
#include "disk.h"
#include "efi-loader-features.h"
#include "graphics.h"
@ -2136,10 +2135,10 @@ static VOID config_load_xbootldr(
EFI_PARTITION_TABLE_HEADER gpt_header;
uint8_t space[((sizeof(EFI_PARTITION_TABLE_HEADER) + 511) / 512) * 512];
} gpt_header_buffer;
const EFI_PARTITION_TABLE_HEADER *h = &gpt_header_buffer.gpt_header;
EFI_PARTITION_TABLE_HEADER *h = &gpt_header_buffer.gpt_header;
UINT64 where;
UINTN sz;
UINT32 c;
UINT32 crc32, crc32_saved;
if (nr == 0)
/* Read the first copy at LBA 1 */
@ -2158,8 +2157,7 @@ static VOID config_load_xbootldr(
continue;
/* Some superficial validation of the GPT header */
c = CompareMem(&h->Header.Signature, "EFI PART", sizeof(h->Header.Signature));
if (c != 0)
if(CompareMem(&h->Header.Signature, "EFI PART", sizeof(h->Header.Signature) != 0))
continue;
if (h->Header.HeaderSize < 92 ||
@ -2170,12 +2168,11 @@ static VOID config_load_xbootldr(
continue;
/* Calculate CRC check */
c = ~crc32_exclude_offset(UINT32_MAX,
(const UINT8*) &gpt_header_buffer,
h->Header.HeaderSize,
OFFSETOF(EFI_PARTITION_TABLE_HEADER, Header.CRC32),
sizeof(h->Header.CRC32));
if (c != h->Header.CRC32)
crc32_saved = h->Header.CRC32;
h->Header.CRC32 = 0;
r = BS->CalculateCrc32(&gpt_header_buffer, h->Header.HeaderSize, &crc32);
h->Header.CRC32 = crc32_saved;
if (EFI_ERROR(r) || crc32 != crc32_saved)
continue;
if (h->MyLBA != where)
@ -2204,8 +2201,8 @@ static VOID config_load_xbootldr(
continue;
/* Calculate CRC of entries array, too */
c = ~crc32(UINT32_MAX, entries, sz);
if (c != h->PartitionEntryArrayCRC32)
r = BS->CalculateCrc32(&entries, sz, &crc32);
if (EFI_ERROR(r) || crc32 != h->PartitionEntryArrayCRC32)
continue;
for (UINTN i = 0; i < h->NumberOfPartitionEntries; i++) {

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@ -1,147 +0,0 @@
/* SPDX-License-Identifier: LicenseRef-crc32-no-restriction */
/* This is copied from util-linux, which in turn copied in the version from Gary S. Brown */
/*
* COPYRIGHT (C) 1986 Gary S. Brown. You may use this program, or
* code or tables extracted from it, as desired without restriction.
*
* First, the polynomial itself and its table of feedback terms. The
* polynomial is
* X^32+X^26+X^23+X^22+X^16+X^12+X^11+X^10+X^8+X^7+X^5+X^4+X^2+X^1+X^0
*
* Note that we take it "backwards" and put the highest-order term in
* the lowest-order bit. The X^32 term is "implied"; the LSB is the
* X^31 term, etc. The X^0 term (usually shown as "+1") results in
* the MSB being 1.
*
* Note that the usual hardware shift register implementation, which
* is what we're using (we're merely optimizing it by doing eight-bit
* chunks at a time) shifts bits into the lowest-order term. In our
* implementation, that means shifting towards the right. Why do we
* do it this way? Because the calculated CRC must be transmitted in
* order from highest-order term to lowest-order term. UARTs transmit
* characters in order from LSB to MSB. By storing the CRC this way,
* we hand it to the UART in the order low-byte to high-byte; the UART
* sends each low-bit to high-bit; and the result is transmission bit
* by bit from highest- to lowest-order term without requiring any bit
* shuffling on our part. Reception works similarly.
*
* The feedback terms table consists of 256, 32-bit entries. Notes
*
* The table can be generated at runtime if desired; code to do so
* is shown later. It might not be obvious, but the feedback
* terms simply represent the results of eight shift/xor opera-
* tions for all combinations of data and CRC register values.
*
* The values must be right-shifted by eight bits by the "updcrc"
* logic; the shift must be unsigned (bring in zeroes). On some
* hardware you could probably optimize the shift in assembler by
* using byte-swap instructions.
* polynomial $edb88320
*
*/
#include "crc32.h"
#include "macro-fundamental.h"
static const UINT32 crc32_tab[] = {
0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
0x2d02ef8dL
};
static inline UINT32 crc32_add_char(UINT32 crc, UINT8 c) {
return crc32_tab[(crc ^ c) & 0xff] ^ (crc >> 8);
}
/*
* This a generic crc32() function, it takes seed as an argument,
* and does __not__ xor at the end. Then individual users can do
* whatever they need.
*/
UINT32 crc32(UINT32 seed, const VOID *buf, UINTN len) {
const UINT8 *p = buf;
UINT32 crc = seed;
assert(buf);
while (len > 0) {
crc = crc32_add_char(crc, *p++);
len--;
}
return crc;
}
UINT32 crc32_exclude_offset(
UINT32 seed,
const VOID *buf,
UINTN len,
UINTN exclude_off,
UINTN exclude_len) {
const UINT8 *p = buf;
UINT32 crc = seed;
assert(buf);
for (UINTN i = 0; i < len; i++) {
UINT8 x = *p++;
if (i >= exclude_off && i < exclude_off + exclude_len)
x = 0;
crc = crc32_add_char(crc, x);
}
return crc;
}

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@ -1,8 +0,0 @@
/* SPDX-License-Identifier: LicenseRef-crc32-no-restriction */
#pragma once
#include <efi.h>
#include <efilib.h>
UINT32 crc32(UINT32 seed, const VOID *buf, UINTN len);
UINT32 crc32_exclude_offset(UINT32 seed, const VOID *buf, UINTN len, UINTN exclude_off, UINTN exclude_len);

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@ -2,7 +2,6 @@
efi_headers = files('''
console.h
crc32.h
disk.h
graphics.h
linux.h
@ -29,7 +28,6 @@ common_sources = '''
systemd_boot_sources = '''
boot.c
console.c
crc32.c
random-seed.c
sha256.c
shim.c