You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
262 lines
11 KiB
262 lines
11 KiB
/*
|
|
* This file is part of the Trezor project, https://trezor.io/
|
|
*
|
|
* Copyright (C) 2014 Pavol Rusnak <stick@satoshilabs.com>
|
|
*
|
|
* This library is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU Lesser General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This library 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 Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public License
|
|
* along with this library. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <string.h>
|
|
|
|
#include "ecdsa.h"
|
|
#include "fw_signatures.h"
|
|
#include "memory.h"
|
|
#include "memzero.h"
|
|
#include "secp256k1.h"
|
|
#include "sha2.h"
|
|
|
|
const uint32_t FIRMWARE_MAGIC_NEW = 0x465a5254; // TRZF
|
|
|
|
/*
|
|
* There are 3 schemes in history of T1, for clarity naming:
|
|
*
|
|
* - v1 - previously called "old" with TRZR magic header (no longer here)
|
|
* - v2 - previously called "new" with TRZF magic header
|
|
* - v3 - the latest scheme using Trezor's SignMessage and VerifyMessage
|
|
* style signatures
|
|
*
|
|
* See `debug_signing/README.md` and the scripts there for signatures debug.
|
|
*
|
|
* Latest scheme v3 ref: https://github.com/trezor/trezor-firmware/issues/2513
|
|
*/
|
|
#define PUBKEYS 5
|
|
|
|
#if DEBUG_T1_SIGNATURES
|
|
|
|
// Make build explode if combining debug sigs with production
|
|
#if PRODUCTION
|
|
#error "Can't have production device with debug keys! Build aborted"
|
|
#endif
|
|
|
|
// These are **only** for debugging signatures with SignMessage
|
|
// Use this mnemonic for testing signing:
|
|
// "table table table table table table table table table table table advance"
|
|
// the "SignMessage"-style public keys, third signing scheme
|
|
// See legacy/debug_signing/README.md
|
|
static const uint8_t * const pubkey_v3[PUBKEYS] = {
|
|
(const uint8_t *)"\x03\x73\x08\xe1\x40\x77\x16\x1c\x36\x5d\xea\x0f\x5c\x80\xaa\x6c\x5d\xba\x34\x71\x9e\x82\x5b\xd2\x3a\xe5\xf7\xe7\xd2\x98\x8a\xdb\x0f",
|
|
(const uint8_t *)"\x03\x9c\x1b\x24\x60\xe3\x43\x71\x2e\x98\x2e\x07\x32\xe7\xed\x17\xf6\x0d\xe4\xc9\x33\x06\x5b\x71\x70\xd9\x9c\x6e\x7f\xe7\xcc\x7f\x4b",
|
|
(const uint8_t *)"\x03\x15\x2b\x37\xfd\xf1\x26\x11\x12\x74\xc8\x94\xc3\x48\xdc\xc9\x75\xb5\x7c\x11\x5e\xe2\x4c\xeb\x19\xb5\x19\x0a\xc7\xf7\xb6\x51\x73",
|
|
(const uint8_t *)"\x02\x83\x91\x8a\xbf\x1b\x6e\x1d\x2a\x1d\x08\xea\x29\xc9\xd2\xae\x2e\x97\xe3\xc0\x1f\x4e\xa8\x59\x2b\x08\x8d\x28\x03\x5b\x44\x4e\xd0",
|
|
(const uint8_t *)"\x03\xc6\x83\x63\x85\x07\x8a\x18\xe8\x1d\x74\x77\x68\x1e\x0d\x30\x86\x66\xf3\x99\x59\x4b\xe9\xe8\xab\xcb\x45\x58\xa6\xe2\x47\x32\xfc"
|
|
};
|
|
|
|
// the "new", or second signing scheme keys
|
|
|
|
/*
|
|
Debug private keys for v2 (previously called "new") scheme
|
|
corresponding to pubkeys below as python hexstring array:
|
|
|
|
['ba7994923c91771ad77c483f7d2b41f5506b82aa900e6f12edeae96c5c9f8f66',
|
|
'81a825d359da7ec9534e6cf7dd190bdbad62e134265764a5ec3e63317b060a51',
|
|
'37107a021e50ca3571102691606083f6a8d9cd600e35cd2c8e8f7b87796a045b',
|
|
'5518381d95e93e8eb68a294354989906e3828f36b4556a2ad85d8333294eb1b7',
|
|
'1d1d34168760dec092c9ff89377d8659076d2dfd95e0281719c15f90d067e211']
|
|
*/
|
|
static const uint8_t * const pubkey_v2[PUBKEYS] = {
|
|
(const uint8_t *)"\x03\x91\xcd\xaf\x3c\xac\x08\xc2\x71\x2e\xe1\xe8\x8c\xd6\xd3\x46\xeb\x2c\x79\x8f\xda\xf9\x5c\x0e\xb6\xef\xee\xa0\xd7\x01\x4d\xac\x87",
|
|
(const uint8_t *)"\x02\x18\x6f\xf4\xe2\xb0\x8b\xc5\xae\x0e\x21\xa5\x08\xf1\xce\xd4\x8f\xf4\x51\xea\xb7\xd7\x94\xde\xb0\xb7\xcb\xe8\xef\xd7\x29\xab\xa7",
|
|
(const uint8_t *)"\x03\x24\x00\x9f\x0b\x39\x8c\xa1\xc3\x35\xfb\x17\xa1\x02\x1c\x3f\x7f\xb0\x83\x1d\xdb\x28\x34\x8a\x4f\x05\x8b\x14\x9e\xa4\xc5\x89\xa0",
|
|
(const uint8_t *)"\x03\x66\x63\x5d\x99\x94\x17\xb6\x55\x66\x86\x6c\x65\x63\x0d\x97\x7a\x7a\xe7\x23\xfe\x5f\x6c\x4c\xd1\x7f\xa0\x0f\x08\x8b\xa1\x84\xc1",
|
|
(const uint8_t *)"\x03\xf3\x6c\x7d\x0f\xb6\x15\xad\xa4\x3d\x71\x88\x58\x0f\x15\xeb\xda\x22\xd6\xf6\xb9\xb1\xa9\x2b\xff\x16\xc6\x93\x77\x99\xdc\xbc\x66"
|
|
};
|
|
#else
|
|
|
|
// These public keys are production keys
|
|
// - used in production devices
|
|
|
|
// the "SignMessage"-style public keys, third signing scheme
|
|
static const uint8_t * const pubkey_v3[PUBKEYS] = {
|
|
(const uint8_t *)"\x02\xd5\x71\xb7\xf1\x48\xc5\xe4\x23\x2c\x38\x14\xf7\x77\xd8\xfa\xea\xf1\xa8\x42\x16\xc7\x8d\x56\x9b\x71\x04\x1f\xfc\x76\x8a\x5b\x2d",
|
|
(const uint8_t *)"\x03\x63\x27\x9c\x0c\x08\x66\xe5\x0c\x05\xc7\x99\xd3\x2b\xd6\xba\xb0\x18\x8b\x6d\xe0\x65\x36\xd1\x10\x9d\x2e\xd9\xce\x76\xcb\x33\x5c",
|
|
(const uint8_t *)"\x02\x43\xae\xdb\xb6\xf7\xe7\x1c\x56\x3f\x8e\xd2\xef\x64\xec\x99\x81\x48\x25\x19\xe7\xef\x4f\x4a\xa9\x8b\x27\x85\x4e\x8c\x49\x12\x6d",
|
|
(const uint8_t *)"\x02\x87\x7c\x39\xfd\x7c\x62\x23\x7e\x03\x82\x35\xe9\xc0\x75\xda\xb2\x61\x63\x0f\x78\xee\xb8\xed\xb9\x24\x87\x15\x9f\xff\xed\xfd\xf6",
|
|
(const uint8_t *)"\x03\x73\x84\xc5\x1a\xe8\x1a\xdd\x0a\x52\x3a\xdb\xb1\x86\xc9\x1b\x90\x6f\xfb\x64\xc2\xc7\x65\x80\x2b\xf2\x6d\xbd\x13\xbd\xf1\x2c\x31"
|
|
};
|
|
|
|
// the "new", or second signing scheme keys
|
|
static const uint8_t * const pubkey_v2[PUBKEYS] = {
|
|
(const uint8_t *)"\x02\xd5\x71\xb7\xf1\x48\xc5\xe4\x23\x2c\x38\x14\xf7\x77\xd8\xfa\xea\xf1\xa8\x42\x16\xc7\x8d\x56\x9b\x71\x04\x1f\xfc\x76\x8a\x5b\x2d",
|
|
(const uint8_t *)"\x03\x63\x27\x9c\x0c\x08\x66\xe5\x0c\x05\xc7\x99\xd3\x2b\xd6\xba\xb0\x18\x8b\x6d\xe0\x65\x36\xd1\x10\x9d\x2e\xd9\xce\x76\xcb\x33\x5c",
|
|
(const uint8_t *)"\x02\x43\xae\xdb\xb6\xf7\xe7\x1c\x56\x3f\x8e\xd2\xef\x64\xec\x99\x81\x48\x25\x19\xe7\xef\x4f\x4a\xa9\x8b\x27\x85\x4e\x8c\x49\x12\x6d",
|
|
(const uint8_t *)"\x02\x87\x7c\x39\xfd\x7c\x62\x23\x7e\x03\x82\x35\xe9\xc0\x75\xda\xb2\x61\x63\x0f\x78\xee\xb8\xed\xb9\x24\x87\x15\x9f\xff\xed\xfd\xf6",
|
|
(const uint8_t *)"\x03\x73\x84\xc5\x1a\xe8\x1a\xdd\x0a\x52\x3a\xdb\xb1\x86\xc9\x1b\x90\x6f\xfb\x64\xc2\xc7\x65\x80\x2b\xf2\x6d\xbd\x13\xbd\xf1\x2c\x31"
|
|
};
|
|
#endif
|
|
|
|
#define SIGNATURES 3
|
|
|
|
#define FLASH_META_START 0x08008000
|
|
#define FLASH_META_CODELEN (FLASH_META_START + 0x0004)
|
|
#define FLASH_META_SIGINDEX1 (FLASH_META_START + 0x0008)
|
|
#define FLASH_META_SIGINDEX2 (FLASH_META_START + 0x0009)
|
|
#define FLASH_META_SIGINDEX3 (FLASH_META_START + 0x000A)
|
|
#define FLASH_OLD_APP_START 0x08010000
|
|
#define FLASH_META_SIG1 (FLASH_META_START + 0x0040)
|
|
#define FLASH_META_SIG2 (FLASH_META_START + 0x0080)
|
|
#define FLASH_META_SIG3 (FLASH_META_START + 0x00C0)
|
|
|
|
/*
|
|
* 0x18 in message prefix is coin info, 0x20 is the length of hash
|
|
* that follows.
|
|
* See `core/src/apps/bitcoin/sign_message.py`.
|
|
*/
|
|
#define VERIFYMESSAGE_PREFIX \
|
|
("\x18" \
|
|
"Bitcoin Signed Message:\n\x20")
|
|
#define PREFIX_LENGTH (sizeof(VERIFYMESSAGE_PREFIX) - 1)
|
|
#define SIGNED_LENGTH (PREFIX_LENGTH + 32)
|
|
|
|
void compute_firmware_fingerprint(const image_header *hdr, uint8_t hash[32]) {
|
|
image_header copy = {0};
|
|
memcpy(©, hdr, sizeof(image_header));
|
|
memzero(copy.sig1, sizeof(copy.sig1));
|
|
memzero(copy.sig2, sizeof(copy.sig2));
|
|
memzero(copy.sig3, sizeof(copy.sig3));
|
|
copy.sigindex1 = 0;
|
|
copy.sigindex2 = 0;
|
|
copy.sigindex3 = 0;
|
|
sha256_Raw((const uint8_t *)©, sizeof(image_header), hash);
|
|
}
|
|
|
|
void compute_firmware_fingerprint_for_verifymessage(const image_header *hdr,
|
|
uint8_t hash[32]) {
|
|
uint8_t prefixed_header[SIGNED_LENGTH] = VERIFYMESSAGE_PREFIX;
|
|
uint8_t header_hash[32];
|
|
uint8_t hash_before_double_hashing[32];
|
|
compute_firmware_fingerprint(hdr, header_hash);
|
|
memcpy(prefixed_header + PREFIX_LENGTH, header_hash, sizeof(header_hash));
|
|
sha256_Raw(prefixed_header, sizeof(prefixed_header),
|
|
hash_before_double_hashing);
|
|
// We need to do hash the previous result again because SignMessage
|
|
// computes it this way, see `core/src/apps/bitcoin/sign_message.py`
|
|
sha256_Raw(hash_before_double_hashing, sizeof(hash_before_double_hashing),
|
|
hash);
|
|
}
|
|
|
|
bool firmware_present_new(void) {
|
|
const image_header *hdr =
|
|
(const image_header *)FLASH_PTR(FLASH_FWHEADER_START);
|
|
if (hdr->magic != FIRMWARE_MAGIC_NEW) return false;
|
|
// we need to ignore hdrlen for now
|
|
// because we keep reset_handler ptr there
|
|
// for compatibility with older bootloaders
|
|
// after this is no longer necessary, let's uncomment the line below:
|
|
// if (hdr->hdrlen != FLASH_FWHEADER_LEN) return false;
|
|
if (hdr->codelen > FLASH_APP_LEN) return false;
|
|
if (hdr->codelen < 4096) return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
int signatures_ok(const image_header *hdr, uint8_t store_fingerprint[32],
|
|
bool use_verifymessage) {
|
|
uint8_t hash[32] = {0};
|
|
// which set of public keys depend on scheme
|
|
const uint8_t *const *pubkey_ptr = NULL;
|
|
if (use_verifymessage) {
|
|
pubkey_ptr = pubkey_v3;
|
|
compute_firmware_fingerprint_for_verifymessage(hdr, hash);
|
|
} else {
|
|
pubkey_ptr = pubkey_v2;
|
|
compute_firmware_fingerprint(hdr, hash);
|
|
}
|
|
|
|
if (store_fingerprint) {
|
|
memcpy(store_fingerprint, hash, 32);
|
|
}
|
|
|
|
if (hdr->sigindex1 < 1 || hdr->sigindex1 > PUBKEYS)
|
|
return SIG_FAIL; // invalid index
|
|
if (hdr->sigindex2 < 1 || hdr->sigindex2 > PUBKEYS)
|
|
return SIG_FAIL; // invalid index
|
|
if (hdr->sigindex3 < 1 || hdr->sigindex3 > PUBKEYS)
|
|
return SIG_FAIL; // invalid index
|
|
|
|
if (hdr->sigindex1 == hdr->sigindex2) return SIG_FAIL; // duplicate use
|
|
if (hdr->sigindex1 == hdr->sigindex3) return SIG_FAIL; // duplicate use
|
|
if (hdr->sigindex2 == hdr->sigindex3) return SIG_FAIL; // duplicate use
|
|
|
|
if (0 != ecdsa_verify_digest(&secp256k1, pubkey_ptr[hdr->sigindex1 - 1],
|
|
hdr->sig1, hash)) { // failure
|
|
return SIG_FAIL;
|
|
}
|
|
if (0 != ecdsa_verify_digest(&secp256k1, pubkey_ptr[hdr->sigindex2 - 1],
|
|
hdr->sig2, hash)) { // failure
|
|
return SIG_FAIL;
|
|
}
|
|
if (0 != ecdsa_verify_digest(&secp256k1, pubkey_ptr[hdr->sigindex3 - 1],
|
|
hdr->sig3, hash)) { // failure
|
|
return SIG_FAIL;
|
|
}
|
|
|
|
return SIG_OK;
|
|
}
|
|
|
|
int signatures_match(const image_header *hdr, uint8_t store_fingerprint[32]) {
|
|
int result = 0;
|
|
// Return success if v3 ("verify message") or the v2 ("new") style matches.
|
|
// Use XOR to always force computing both signatures to avoid potential
|
|
// timing side channels.
|
|
// Return only the hash for the v2 computation so that it is
|
|
// the same shown in previous bootloader.
|
|
result ^= signatures_ok(hdr, store_fingerprint, false);
|
|
result ^= signatures_ok(hdr, NULL, true);
|
|
if (result != SIG_OK) {
|
|
return SIG_FAIL;
|
|
}
|
|
return SIG_OK;
|
|
}
|
|
|
|
int mem_is_empty(const uint8_t *src, uint32_t len) {
|
|
for (uint32_t i = 0; i < len; i++) {
|
|
if (src[i]) return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
int check_firmware_hashes(const image_header *hdr) {
|
|
uint8_t hash[32] = {0};
|
|
// check hash of the first code chunk
|
|
sha256_Raw(FLASH_PTR(FLASH_APP_START), (64 - 1) * 1024, hash);
|
|
if (0 != memcmp(hash, hdr->hashes, 32)) return SIG_FAIL;
|
|
// check remaining used chunks
|
|
uint32_t total_len = FLASH_FWHEADER_LEN + hdr->codelen;
|
|
int used_chunks = total_len / FW_CHUNK_SIZE;
|
|
if (total_len % FW_CHUNK_SIZE > 0) {
|
|
used_chunks++;
|
|
}
|
|
for (int i = 1; i < used_chunks; i++) {
|
|
sha256_Raw(FLASH_PTR(FLASH_FWHEADER_START + (64 * i) * 1024), 64 * 1024,
|
|
hash);
|
|
if (0 != memcmp(hdr->hashes + 32 * i, hash, 32)) return SIG_FAIL;
|
|
}
|
|
// check unused chunks
|
|
for (int i = used_chunks; i < 16; i++) {
|
|
if (!mem_is_empty(hdr->hashes + 32 * i, 32)) return SIG_FAIL;
|
|
}
|
|
// all OK
|
|
return SIG_OK;
|
|
}
|