From 1f2409e9e2c15e1b96c2bcb3d7bfd77091b2a504 Mon Sep 17 00:00:00 2001 From: stoffu Date: Thu, 16 Aug 2018 22:08:58 +0900 Subject: [PATCH] Do memwipe for critical secret keys copied to rct::key --- src/cryptonote_core/cryptonote_tx_utils.cpp | 3 +++ src/multisig/multisig.cpp | 5 ++++- src/ringct/rctSigs.cpp | 8 ++++++-- src/wallet/wallet2.cpp | 2 ++ 4 files changed, 15 insertions(+), 3 deletions(-) diff --git a/src/cryptonote_core/cryptonote_tx_utils.cpp b/src/cryptonote_core/cryptonote_tx_utils.cpp index 071ce591e..1581f3088 100644 --- a/src/cryptonote_core/cryptonote_tx_utils.cpp +++ b/src/cryptonote_core/cryptonote_tx_utils.cpp @@ -516,6 +516,7 @@ namespace cryptonote uint64_t amount_in = 0, amount_out = 0; rct::ctkeyV inSk; + inSk.reserve(sources.size()); // mixRing indexing is done the other way round for simple rct::ctkeyM mixRing(use_simple_rct ? sources.size() : n_total_outs); rct::keyV destinations; @@ -532,6 +533,7 @@ namespace cryptonote ctkey.dest = rct::sk2rct(in_contexts[i].in_ephemeral.sec); ctkey.mask = sources[i].mask; inSk.push_back(ctkey); + memwipe(&ctkey, sizeof(rct::ctkey)); // inPk: (public key, commitment) // will be done when filling in mixRing if (msout) @@ -590,6 +592,7 @@ namespace cryptonote tx.rct_signatures = rct::genRctSimple(rct::hash2rct(tx_prefix_hash), inSk, destinations, inamounts, outamounts, amount_in - amount_out, mixRing, amount_keys, msout ? &kLRki : NULL, msout, index, outSk, bulletproof, hwdev); else tx.rct_signatures = rct::genRct(rct::hash2rct(tx_prefix_hash), inSk, destinations, outamounts, mixRing, amount_keys, msout ? &kLRki[0] : NULL, msout, sources[0].real_output, outSk, bulletproof, hwdev); // same index assumption + memwipe(inSk.data(), inSk.size() * sizeof(rct::ctkey)); CHECK_AND_ASSERT_MES(tx.vout.size() == outSk.size(), false, "outSk size does not match vout"); diff --git a/src/multisig/multisig.cpp b/src/multisig/multisig.cpp index d85c47772..a0a788b7d 100644 --- a/src/multisig/multisig.cpp +++ b/src/multisig/multisig.cpp @@ -47,9 +47,12 @@ namespace cryptonote crypto::secret_key get_multisig_blinded_secret_key(const crypto::secret_key &key) { rct::keyV data; + data.reserve(2); data.push_back(rct::sk2rct(key)); data.push_back(multisig_salt); - return rct::rct2sk(rct::hash_to_scalar(data)); + crypto::secret_key result = rct::rct2sk(rct::hash_to_scalar(data)); + memwipe(&data[0], sizeof(rct::key)); + return result; } //----------------------------------------------------------------- void generate_multisig_N_N(const account_keys &keys, const std::vector &spend_keys, std::vector &multisig_keys, rct::key &spend_skey, rct::key &spend_pkey) diff --git a/src/ringct/rctSigs.cpp b/src/ringct/rctSigs.cpp index f74216ed4..cc966c44b 100644 --- a/src/ringct/rctSigs.cpp +++ b/src/ringct/rctSigs.cpp @@ -492,7 +492,9 @@ namespace rct { for (size_t j = 0; j < outPk.size(); j++) { sc_sub(sk[rows].bytes, sk[rows].bytes, outSk[j].mask.bytes); //subtract output masks in last row.. } - return MLSAG_Gen(message, M, sk, kLRki, mscout, index, rows, hwdev); + mgSig result = MLSAG_Gen(message, M, sk, kLRki, mscout, index, rows, hwdev); + memwipe(sk.data(), sk.size() * sizeof(key)); + return result; } @@ -521,7 +523,9 @@ namespace rct { M[i][0] = pubs[i].dest; subKeys(M[i][1], pubs[i].mask, Cout); } - return MLSAG_Gen(message, M, sk, kLRki, mscout, index, rows, hwdev); + mgSig result = MLSAG_Gen(message, M, sk, kLRki, mscout, index, rows, hwdev); + memwipe(&sk[0], sizeof(key)); + return result; } diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp index 9deaad09b..6b6e9865f 100644 --- a/src/wallet/wallet2.cpp +++ b/src/wallet/wallet2.cpp @@ -3217,6 +3217,7 @@ void wallet2::generate(const std::string& wallet_, const epee::wipeable_string& for (const auto &msk: multisig_keys) sc_add(skey.bytes, skey.bytes, rct::sk2rct(msk).bytes); THROW_WALLET_EXCEPTION_IF(!(rct::rct2sk(skey) == spend_secret_key), error::invalid_multisig_seed); + memwipe(&skey, sizeof(rct::key)); m_account.make_multisig(view_secret_key, spend_secret_key, spend_public_key, multisig_keys); m_account.finalize_multisig(spend_public_key); @@ -3563,6 +3564,7 @@ std::string wallet2::make_multisig(const epee::wipeable_string &password, MINFO("Creating multisig address..."); CHECK_AND_ASSERT_THROW_MES(m_account.make_multisig(view_skey, rct::rct2sk(spend_skey), rct::rct2pk(spend_pkey), multisig_keys), "Failed to create multisig wallet due to bad keys"); + memwipe(&spend_skey, sizeof(rct::key)); m_account_public_address = m_account.get_keys().m_account_address; m_watch_only = false;