mirror of
https://github.com/trezor/trezor-firmware.git
synced 2024-12-30 01:58:11 +00:00
96 lines
2.9 KiB
C
96 lines
2.9 KiB
C
#include <string.h>
|
|
|
|
#include "blake2s.h"
|
|
#include "ed25519-donna/ed25519.h"
|
|
|
|
#include "common.h"
|
|
#include "image.h"
|
|
|
|
bool image_parse_header(const uint8_t *data, image_header *header)
|
|
{
|
|
if (!header) {
|
|
image_header h;
|
|
header = &h;
|
|
}
|
|
|
|
memcpy(&header->magic, data, 4);
|
|
if (header->magic != IMAGE_MAGIC) return false;
|
|
|
|
memcpy(&header->hdrlen, data + 4, 4);
|
|
if (header->hdrlen != HEADER_SIZE) return false;
|
|
|
|
memcpy(&header->expiry, data + 8, 4);
|
|
if (header->expiry != 0) return false;
|
|
|
|
memcpy(&header->codelen, data + 12, 4);
|
|
if (header->hdrlen + header->codelen < 4 * 1024) return false;
|
|
if (header->hdrlen + header->codelen > IMAGE_MAXSIZE) return false;
|
|
if ((header->hdrlen + header->codelen) % 512 != 0) return false;
|
|
|
|
memcpy(&header->version, data + 16, 4);
|
|
|
|
// uint8_t reserved[427];
|
|
|
|
memcpy(&header->sigmask, data + 0x01BF, 1);
|
|
|
|
memcpy(header->sig, data + 0x01C0, 64);
|
|
|
|
return true;
|
|
}
|
|
|
|
#define KEYMASK(A, B, C) ((1 << (A - 1)) | (1 << (B - 1)) | (1 << (C - 1)))
|
|
|
|
static const uint8_t *get_pubkey(uint8_t index)
|
|
{
|
|
switch (index) {
|
|
case KEYMASK(1, 2, 3):
|
|
return (const uint8_t *)"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
|
|
case KEYMASK(1, 2, 4):
|
|
return (const uint8_t *)"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
|
|
case KEYMASK(1, 2, 5):
|
|
return (const uint8_t *)"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
|
|
case KEYMASK(1, 3, 4):
|
|
return (const uint8_t *)"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
|
|
case KEYMASK(1, 3, 5):
|
|
return (const uint8_t *)"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
|
|
case KEYMASK(1, 4, 5):
|
|
return (const uint8_t *)"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
|
|
case KEYMASK(2, 3, 4):
|
|
return (const uint8_t *)"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
|
|
case KEYMASK(2, 3, 5):
|
|
return (const uint8_t *)"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
|
|
case KEYMASK(2, 4, 5):
|
|
return (const uint8_t *)"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
|
|
case KEYMASK(3, 4, 5):
|
|
return (const uint8_t *)"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
|
|
default:
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
bool image_check_signature(const uint8_t *data)
|
|
{
|
|
image_header hdr;
|
|
if (!image_parse_header(data, &hdr)) {
|
|
return false;
|
|
}
|
|
|
|
uint8_t hash[BLAKE2S_DIGEST_LENGTH];
|
|
BLAKE2S_CTX ctx;
|
|
blake2s_Init(&ctx, BLAKE2S_DIGEST_LENGTH);
|
|
blake2s_Update(&ctx, data, HEADER_SIZE - 65);
|
|
for (int i = 0; i < 65; i++) {
|
|
blake2s_Update(&ctx, (const uint8_t *)"\x00", 1);
|
|
}
|
|
blake2s_Update(&ctx, data + HEADER_SIZE, hdr.codelen);
|
|
blake2s_Final(&ctx, hash, BLAKE2S_DIGEST_LENGTH);
|
|
|
|
const uint8_t *pub = get_pubkey(hdr.sigmask);
|
|
|
|
// TODO: remove debug skip of unsigned
|
|
if (!pub) return true;
|
|
// end
|
|
|
|
return pub && (0 == ed25519_sign_open(hash, BLAKE2S_DIGEST_LENGTH, *(const ed25519_public_key *)pub, *(const ed25519_signature *)hdr.sig));
|
|
}
|