Browse Source

Merge #7891: Always require OS randomness when generating secret keys

628cf14 Don't use assert for catching randomness failures (Pieter Wuille)
fa2637a Always require OS randomness when generating secret keys (Pieter Wuille)
pull/1/head
Pieter Wuille 6 years ago
parent
commit
950be19727
No known key found for this signature in database
GPG Key ID: DBA1A67379A1A931
  1. 3
      src/Makefile.am
  2. 2
      src/init.cpp
  3. 3
      src/key.cpp
  4. 1
      src/main.cpp
  5. 66
      src/random.cpp
  6. 11
      src/random.h
  7. 8
      src/wallet/wallet.cpp

3
src/Makefile.am

@ -374,7 +374,8 @@ endif @@ -374,7 +374,8 @@ endif
bitcoin_cli_LDADD = \
$(LIBBITCOIN_CLI) \
$(LIBUNIVALUE) \
$(LIBBITCOIN_UTIL)
$(LIBBITCOIN_UTIL) \
$(LIBBITCOIN_CRYPTO)
bitcoin_cli_LDADD += $(BOOST_LIBS) $(SSL_LIBS) $(CRYPTO_LIBS) $(EVENT_LIBS)
#

2
src/init.cpp

@ -1401,8 +1401,6 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler) @@ -1401,8 +1401,6 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
if (!strErrors.str().empty())
return InitError(strErrors.str());
RandAddSeedPerfmon();
//// debug print
LogPrintf("mapBlockIndex.size() = %u\n", mapBlockIndex.size());
LogPrintf("nBestHeight = %d\n", chainActive.Height());

3
src/key.cpp

@ -124,9 +124,8 @@ bool CKey::Check(const unsigned char *vch) { @@ -124,9 +124,8 @@ bool CKey::Check(const unsigned char *vch) {
}
void CKey::MakeNewKey(bool fCompressedIn) {
RandAddSeedPerfmon();
do {
GetRandBytes(vch, sizeof(vch));
GetStrongRandBytes(vch, sizeof(vch));
} while (!Check(vch));
fValid = true;
fCompressed = fCompressedIn;

1
src/main.cpp

@ -4547,7 +4547,6 @@ void static ProcessGetData(CNode* pfrom, const Consensus::Params& consensusParam @@ -4547,7 +4547,6 @@ void static ProcessGetData(CNode* pfrom, const Consensus::Params& consensusParam
bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv, int64_t nTimeReceived, const CChainParams& chainparams)
{
RandAddSeedPerfmon();
LogPrint("net", "received: %s (%u bytes) peer=%d\n", SanitizeString(strCommand), vRecv.size(), pfrom->id);
if (mapArgs.count("-dropmessagestest") && GetRand(atoi(mapArgs["-dropmessagestest"])) == 0)
{

66
src/random.cpp

@ -5,14 +5,17 @@ @@ -5,14 +5,17 @@
#include "random.h"
#include "crypto/sha512.h"
#include "support/cleanse.h"
#ifdef WIN32
#include "compat.h" // for Windows API
#include <wincrypt.h>
#endif
#include "serialize.h" // for begin_ptr(vec)
#include "util.h" // for LogPrint()
#include "utilstrencodings.h" // for GetTime()
#include <stdlib.h>
#include <limits>
#ifndef WIN32
@ -22,6 +25,12 @@ @@ -22,6 +25,12 @@
#include <openssl/err.h>
#include <openssl/rand.h>
static void RandFailure()
{
LogPrintf("Failed to read randomness, aborting\n");
abort();
}
static inline int64_t GetPerformanceCounter()
{
int64_t nCounter = 0;
@ -43,7 +52,7 @@ void RandAddSeed() @@ -43,7 +52,7 @@ void RandAddSeed()
memory_cleanse((void*)&nCounter, sizeof(nCounter));
}
void RandAddSeedPerfmon()
static void RandAddSeedPerfmon()
{
RandAddSeed();
@ -83,14 +92,65 @@ void RandAddSeedPerfmon() @@ -83,14 +92,65 @@ void RandAddSeedPerfmon()
#endif
}
/** Get 32 bytes of system entropy. */
static void GetOSRand(unsigned char *ent32)
{
#ifdef WIN32
HCRYPTPROV hProvider;
int ret = CryptAcquireContextW(&hProvider, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT);
if (!ret) {
RandFailure();
}
ret = CryptGenRandom(hProvider, 32, ent32);
if (!ret) {
RandFailure();
}
CryptReleaseContext(hProvider, 0);
#else
int f = open("/dev/urandom", O_RDONLY);
if (f == -1) {
RandFailure();
}
int have = 0;
do {
ssize_t n = read(f, ent32 + have, 32 - have);
if (n <= 0 || n + have > 32) {
RandFailure();
}
have += n;
} while (have < 32);
close(f);
#endif
}
void GetRandBytes(unsigned char* buf, int num)
{
if (RAND_bytes(buf, num) != 1) {
LogPrintf("%s: OpenSSL RAND_bytes() failed with error: %s\n", __func__, ERR_error_string(ERR_get_error(), NULL));
assert(false);
RandFailure();
}
}
void GetStrongRandBytes(unsigned char* out, int num)
{
assert(num <= 32);
CSHA512 hasher;
unsigned char buf[64];
// First source: OpenSSL's RNG
RandAddSeedPerfmon();
GetRandBytes(buf, 32);
hasher.Write(buf, 32);
// Second source: OS RNG
GetOSRand(buf);
hasher.Write(buf, 32);
// Produce output
hasher.Finalize(buf);
memcpy(out, buf, num);
memory_cleanse(buf, 64);
}
uint64_t GetRand(uint64_t nMax)
{
if (nMax == 0)

11
src/random.h

@ -10,11 +10,8 @@ @@ -10,11 +10,8 @@
#include <stdint.h>
/**
* Seed OpenSSL PRNG with additional entropy data
*/
/* Seed OpenSSL PRNG with additional entropy data */
void RandAddSeed();
void RandAddSeedPerfmon();
/**
* Functions to gather random data via the OpenSSL PRNG
@ -24,6 +21,12 @@ uint64_t GetRand(uint64_t nMax); @@ -24,6 +21,12 @@ uint64_t GetRand(uint64_t nMax);
int GetRandInt(int nMax);
uint256 GetRandHash();
/**
* Function to gather random data from multiple sources, failing whenever any
* of those source fail to provide a result.
*/
void GetStrongRandBytes(unsigned char* buf, int num);
/**
* Seed insecure_rand using the random pool.
* @param Deterministic Use a deterministic seed

8
src/wallet/wallet.cpp

@ -509,16 +509,14 @@ bool CWallet::EncryptWallet(const SecureString& strWalletPassphrase) @@ -509,16 +509,14 @@ bool CWallet::EncryptWallet(const SecureString& strWalletPassphrase)
return false;
CKeyingMaterial vMasterKey;
RandAddSeedPerfmon();
vMasterKey.resize(WALLET_CRYPTO_KEY_SIZE);
GetRandBytes(&vMasterKey[0], WALLET_CRYPTO_KEY_SIZE);
GetStrongRandBytes(&vMasterKey[0], WALLET_CRYPTO_KEY_SIZE);
CMasterKey kMasterKey;
RandAddSeedPerfmon();
kMasterKey.vchSalt.resize(WALLET_CRYPTO_SALT_SIZE);
GetRandBytes(&kMasterKey.vchSalt[0], WALLET_CRYPTO_SALT_SIZE);
GetStrongRandBytes(&kMasterKey.vchSalt[0], WALLET_CRYPTO_SALT_SIZE);
CCrypter crypter;
int64_t nStartTime = GetTimeMillis();
@ -3147,8 +3145,6 @@ bool CWallet::InitLoadWallet() @@ -3147,8 +3145,6 @@ bool CWallet::InitLoadWallet()
if (fFirstRun)
{
// Create new keyUser and set as default key
RandAddSeedPerfmon();
CPubKey newDefaultKey;
if (walletInstance->GetKeyFromPool(newDefaultKey)) {
walletInstance->SetDefaultKey(newDefaultKey);

Loading…
Cancel
Save