Files
app-ethereum/src_common/ethUtils.c
2020-11-30 18:22:17 +01:00

307 lines
9.4 KiB
C

/*******************************************************************************
* Ledger Ethereum App
* (c) 2016-2019 Ledger
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
********************************************************************************/
/**
* @brief Utilities for an Ethereum Hardware Wallet logic
* @file ethUtils.h
* @author Ledger Firmware Team <hello@ledger.fr>
* @version 1.0
* @date 8th of March 2016
*/
#include <stdbool.h>
#include <stdint.h>
#include <string.h>
#include "os.h"
#include "cx.h"
#include "ethUtils.h"
#include "chainConfig.h"
bool rlpCanDecode(uint8_t *buffer, uint32_t bufferLength, bool *valid) {
if (*buffer <= 0x7f) {
} else if (*buffer <= 0xb7) {
} else if (*buffer <= 0xbf) {
if (bufferLength < (1 + (*buffer - 0xb7))) {
return false;
}
if (*buffer > 0xbb) {
*valid = false; // arbitrary 32 bits length limitation
return true;
}
} else if (*buffer <= 0xf7) {
} else {
if (bufferLength < (1 + (*buffer - 0xf7))) {
return false;
}
if (*buffer > 0xfb) {
*valid = false; // arbitrary 32 bits length limitation
return true;
}
}
*valid = true;
return true;
}
bool rlpDecodeLength(uint8_t *buffer, uint32_t bufferLength,
uint32_t *fieldLength, uint32_t *offset, bool *list) {
if (*buffer <= 0x7f) {
*offset = 0;
*fieldLength = 1;
*list = false;
} else if (*buffer <= 0xb7) {
*offset = 1;
*fieldLength = *buffer - 0x80;
*list = false;
} else if (*buffer <= 0xbf) {
*offset = 1 + (*buffer - 0xb7);
*list = false;
switch (*buffer) {
case 0xb8:
*fieldLength = *(buffer + 1);
break;
case 0xb9:
*fieldLength = (*(buffer + 1) << 8) + *(buffer + 2);
break;
case 0xba:
*fieldLength =
(*(buffer + 1) << 16) + (*(buffer + 2) << 8) + *(buffer + 3);
break;
case 0xbb:
*fieldLength = (*(buffer + 1) << 24) + (*(buffer + 2) << 16) +
(*(buffer + 3) << 8) + *(buffer + 4);
break;
default:
return false; // arbitrary 32 bits length limitation
}
} else if (*buffer <= 0xf7) {
*offset = 1;
*fieldLength = *buffer - 0xc0;
*list = true;
} else {
*offset = 1 + (*buffer - 0xf7);
*list = true;
switch (*buffer) {
case 0xf8:
*fieldLength = *(buffer + 1);
break;
case 0xf9:
*fieldLength = (*(buffer + 1) << 8) + *(buffer + 2);
break;
case 0xfa:
*fieldLength =
(*(buffer + 1) << 16) + (*(buffer + 2) << 8) + *(buffer + 3);
break;
case 0xfb:
*fieldLength = (*(buffer + 1) << 24) + (*(buffer + 2) << 16) +
(*(buffer + 3) << 8) + *(buffer + 4);
break;
default:
return false; // arbitrary 32 bits length limitation
}
}
return true;
}
void getEthAddressFromKey(cx_ecfp_public_key_t *publicKey, uint8_t *out,
cx_sha3_t *sha3Context) {
uint8_t hashAddress[32];
cx_keccak_init(sha3Context, 256);
cx_hash((cx_hash_t*)sha3Context, CX_LAST, publicKey->W + 1, 64, hashAddress, 32);
memmove(out, hashAddress + 12, 20);
}
#ifdef CHECKSUM_1
static const uint8_t const HEXDIGITS[] = "0123456789ABCDEF";
static const uint8_t const MASK[] = {0x80, 0x40, 0x20, 0x10,
0x08, 0x04, 0x02, 0x01};
char convertDigit(uint8_t *address, uint8_t index, uint8_t *hash) {
unsigned char digit = address[index / 2];
if ((index % 2) == 0) {
digit = (digit >> 4) & 0x0f;
} else {
digit = digit & 0x0f;
}
if (digit < 10) {
return HEXDIGITS[digit];
} else {
unsigned char data = hash[index / 8];
if (((data & MASK[index % 8]) != 0) && (digit > 9)) {
return HEXDIGITS[digit] /*- 'a' + 'A'*/;
} else {
return HEXDIGITS[digit];
}
}
}
void getEthAddressStringFromKey(cx_ecfp_public_key_t *publicKey, uint8_t *out,
cx_sha3_t *sha3Context, chain_config_t* chain_config) {
uint8_t hashAddress[32];
cx_keccak_init(sha3Context, 256);
cx_hash((cx_hash_t*)sha3Context, CX_LAST, publicKey->W + 1, 64, hashAddress, 32);
getEthAddressStringFromBinary(hashAddress + 12, out, sha3Context, chain_config);
}
void getEthAddressStringFromBinary(uint8_t *address, uint8_t *out,
cx_sha3_t *sha3Context, chain_config_t* chain_config) {
UNUSED(chain_config);
uint8_t hashChecksum[32];
uint8_t i;
cx_keccak_init(sha3Context, 256);
cx_hash((cx_hash_t*)sha3Context, CX_LAST, address, 20, hashChecksum, 32);
for (i = 0; i < 40; i++) {
out[i] = convertDigit(address, i, hashChecksum);
}
out[40] = '\0';
}
#else
static const uint8_t const HEXDIGITS[] = "0123456789abcdef";
void getEthAddressStringFromKey(cx_ecfp_public_key_t *publicKey, uint8_t *out,
cx_sha3_t *sha3Context, chain_config_t* chain_config) {
uint8_t hashAddress[32];
cx_keccak_init(sha3Context, 256);
cx_hash((cx_hash_t*)sha3Context, CX_LAST, publicKey->W + 1, 64, hashAddress, 32);
getEthAddressStringFromBinary(hashAddress + 12, out, sha3Context, chain_config);
}
void getEthAddressStringFromBinary(uint8_t *address, uint8_t *out,
cx_sha3_t *sha3Context, chain_config_t* chain_config) {
// save some precious stack space
union locals_union
{
uint8_t hashChecksum[32];
uint8_t tmp[51];
} locals_union;
uint8_t i;
bool eip1191 = false;
uint32_t offset = 0;
switch(chain_config->chainId) {
case 30:
case 31:
eip1191 = true;
break;
}
if (eip1191) {
snprintf((char*)locals_union.tmp, sizeof(locals_union.tmp), "%d0x", chain_config->chainId);
offset = strlen((char*)locals_union.tmp);
}
for (i = 0; i < 20; i++) {
uint8_t digit = address[i];
locals_union.tmp[offset + 2 * i] = HEXDIGITS[(digit >> 4) & 0x0f];
locals_union.tmp[offset + 2 * i + 1] = HEXDIGITS[digit & 0x0f];
}
cx_keccak_init(sha3Context, 256);
cx_hash((cx_hash_t*)sha3Context, CX_LAST, locals_union.tmp, offset + 40, locals_union.hashChecksum, 32);
for (i = 0; i < 40; i++) {
uint8_t digit = address[i / 2];
if ((i % 2) == 0) {
digit = (digit >> 4) & 0x0f;
} else {
digit = digit & 0x0f;
}
if (digit < 10) {
out[i] = HEXDIGITS[digit];
}
else {
int v = (locals_union.hashChecksum[i / 2] >> (4 * (1 - i % 2))) & 0x0f;
if (v >= 8) {
out[i] = HEXDIGITS[digit] - 'a' + 'A';
}
else {
out[i] = HEXDIGITS[digit];
}
}
}
out[40] = '\0';
}
#endif
bool adjustDecimals(char *src, uint32_t srcLength, char *target,
uint32_t targetLength, uint8_t decimals) {
uint32_t startOffset;
uint32_t lastZeroOffset = 0;
uint32_t offset = 0;
if ((srcLength == 1) && (*src == '0')) {
if (targetLength < 2) {
return false;
}
target[0] = '0';
target[1] = '\0';
return true;
}
if (srcLength <= decimals) {
uint32_t delta = decimals - srcLength;
if (targetLength < srcLength + 1 + 2 + delta) {
return false;
}
target[offset++] = '0';
target[offset++] = '.';
for (uint32_t i = 0; i < delta; i++) {
target[offset++] = '0';
}
startOffset = offset;
for (uint32_t i = 0; i < srcLength; i++) {
target[offset++] = src[i];
}
target[offset] = '\0';
} else {
uint32_t sourceOffset = 0;
uint32_t delta = srcLength - decimals;
if (targetLength < srcLength + 1 + 1) {
return false;
}
while (offset < delta) {
target[offset++] = src[sourceOffset++];
}
if (decimals != 0) {
target[offset++] = '.';
}
startOffset = offset;
while (sourceOffset < srcLength) {
target[offset++] = src[sourceOffset++];
}
target[offset] = '\0';
}
for (uint32_t i = startOffset; i < offset; i++) {
if (target[i] == '0') {
if (lastZeroOffset == 0) {
lastZeroOffset = i;
}
} else {
lastZeroOffset = 0;
}
}
if (lastZeroOffset != 0) {
target[lastZeroOffset] = '\0';
if (target[lastZeroOffset - 1] == '.') {
target[lastZeroOffset - 1] = '\0';
}
}
return true;
}