1
0
mirror of https://github.com/trezor/trezor-firmware.git synced 2024-11-25 17:09:44 +00:00

implement bip39 cache

This commit is contained in:
Pavol Rusnak 2016-01-19 15:11:57 +01:00
parent 3556c74740
commit 9a8e982153
No known key found for this signature in database
GPG Key ID: 91F3B339B9A02A3D
3 changed files with 54 additions and 4 deletions

47
bip39.c
View File

@ -22,6 +22,7 @@
*/
#include <string.h>
#include <stdbool.h>
#include "bip39.h"
#include "hmac.h"
@ -29,6 +30,20 @@
#include "sha2.h"
#include "pbkdf2.h"
#include "bip39_english.h"
#include "options.h"
#if USE_BIP39_CACHE
static int bip39_cache_index = 0;
static struct {
bool set;
char mnemonic[256];
char passphrase[64];
uint8_t seed[512 / 8];
} bip39_cache[BIP39_CACHE_SIZE];
#endif
const char *mnemonic_generate(int strength)
{
@ -148,12 +163,36 @@ int mnemonic_check(const char *mnemonic)
// passphrase must be at most 256 characters or code may crash
void mnemonic_to_seed(const char *mnemonic, const char *passphrase, uint8_t seed[512 / 8], void (*progress_callback)(uint32_t current, uint32_t total))
{
int passphraselen = strlen(passphrase);
#if USE_BIP39_CACHE
int mnemoniclen = strlen(mnemonic);
// check cache
if (mnemoniclen < 256 && passphraselen < 64) {
int i;
for (i = 0; i < BIP39_CACHE_SIZE; i++) {
if (!bip39_cache[i].set) continue;
if (strcmp(bip39_cache[i].mnemonic, mnemonic) != 0) continue;
if (strcmp(bip39_cache[i].passphrase, passphrase) != 0) continue;
// found the correct entry
memcpy(seed, bip39_cache[i].seed, 512 / 8);
return;
}
}
#endif
uint8_t salt[8 + 256 + 4];
int saltlen = strlen(passphrase);
memcpy(salt, "mnemonic", 8);
memcpy(salt + 8, passphrase, saltlen);
saltlen += 8;
pbkdf2_hmac_sha512((const uint8_t *)mnemonic, strlen(mnemonic), salt, saltlen, BIP39_PBKDF2_ROUNDS, seed, 512 / 8, progress_callback);
memcpy(salt + 8, passphrase, passphraselen);
pbkdf2_hmac_sha512((const uint8_t *)mnemonic, strlen(mnemonic), salt, passphraselen + 8, BIP39_PBKDF2_ROUNDS, seed, 512 / 8, progress_callback);
#if USE_BIP39_CACHE
// store to cache
if (mnemoniclen < 256 && passphraselen < 64) {
bip39_cache[bip39_cache_index].set = true;
strcpy(bip39_cache[bip39_cache_index].mnemonic, mnemonic);
strcpy(bip39_cache[bip39_cache_index].passphrase, passphrase);
memcpy(bip39_cache[bip39_cache_index].seed, seed, 512 / 8);
bip39_cache_index = (bip39_cache_index + 1) % BIP39_CACHE_SIZE;
}
#endif
}
const char * const *mnemonic_wordlist(void)

View File

@ -50,4 +50,10 @@
#define BIP32_CACHE_MAXDEPTH 8
#endif
// implement BIP39 caching
#ifndef USE_BIP39_CACHE
#define USE_BIP39_CACHE 1
#define BIP39_CACHE_SIZE 4
#endif
#endif

View File

@ -880,6 +880,11 @@ START_TEST(test_mnemonic)
ck_assert_str_eq(m, *b);
mnemonic_to_seed(m, "TREZOR", seed, 0);
ck_assert_mem_eq(seed, fromhex(*c), strlen(*c) / 2);
#if USE_BIP39_CACHE
// try second time to check whether caching results work
mnemonic_to_seed(m, "TREZOR", seed, 0);
ck_assert_mem_eq(seed, fromhex(*c), strlen(*c) / 2);
#endif
a += 3; b += 3; c += 3;
}
}