multisig: fix #8537 seed restore (suggestions by @UkoeHB)

- spend secret key is no longer the sum of multisig key shares;
no need to check that is the case upon restore.
- restoring a multisig wallet from multisig info means that the
wallet must have already completed all setup rounds. Upon restore,
set the number of rounds completed accordingly.
This commit is contained in:
j-berman 2022-09-01 16:25:28 -07:00
parent 727bc5b687
commit fc8a5d68f1
6 changed files with 26 additions and 11 deletions

View file

@ -127,7 +127,7 @@ namespace multisig
bool multisig_account::multisig_is_ready() const
{
if (main_kex_rounds_done())
return m_kex_rounds_complete >= multisig_kex_rounds_required(m_signers.size(), m_threshold) + 1;
return m_kex_rounds_complete >= multisig_setup_rounds_required(m_signers.size(), m_threshold);
else
return false;
}
@ -200,4 +200,11 @@ namespace multisig
return num_signers - threshold + 1;
}
//----------------------------------------------------------------------------------------------------------------------
// EXTERNAL
//----------------------------------------------------------------------------------------------------------------------
std::uint32_t multisig_setup_rounds_required(const std::uint32_t num_signers, const std::uint32_t threshold)
{
return multisig_kex_rounds_required(num_signers, threshold) + 1;
}
//----------------------------------------------------------------------------------------------------------------------
} //namespace multisig

View file

@ -245,4 +245,13 @@ namespace multisig
* return: number of kex rounds required
*/
std::uint32_t multisig_kex_rounds_required(const std::uint32_t num_signers, const std::uint32_t threshold);
/**
* brief: multisig_setup_rounds_required - The number of setup rounds required to produce an M-of-N shared key.
* - A participant must complete all kex rounds and 1 initialization round.
* param: num_signers - number of participants in multisig (N)
* param: threshold - threshold of multisig (M)
* return: number of setup rounds required
*/
std::uint32_t multisig_setup_rounds_required(const std::uint32_t num_signers, const std::uint32_t threshold);
} //namespace multisig

View file

@ -74,7 +74,7 @@ namespace multisig
"Multisig threshold may not be larger than number of signers.");
CHECK_AND_ASSERT_THROW_MES(threshold > 0, "Multisig threshold must be > 0.");
CHECK_AND_ASSERT_THROW_MES(round > 0, "Multisig kex round must be > 0.");
CHECK_AND_ASSERT_THROW_MES(round <= multisig_kex_rounds_required(num_signers, threshold) + 1,
CHECK_AND_ASSERT_THROW_MES(round <= multisig_setup_rounds_required(num_signers, threshold),
"Trying to process multisig kex for an invalid round.");
}
//----------------------------------------------------------------------------------------------------------------------

View file

@ -4684,7 +4684,8 @@ void wallet2::init_type(hw::device::device_type device_type)
}
/*!
* \brief Generates a wallet or restores one.
* \brief Generates a wallet or restores one. Assumes the multisig setup
* has already completed for the provided multisig info.
* \param wallet_ Name of wallet file
* \param password Password of wallet file
* \param multisig_data The multisig restore info and keys
@ -4743,11 +4744,6 @@ void wallet2::generate(const std::string& wallet_, const epee::wipeable_string&
crypto::public_key local_signer;
THROW_WALLET_EXCEPTION_IF(!crypto::secret_key_to_public_key(spend_secret_key, local_signer), error::invalid_multisig_seed);
THROW_WALLET_EXCEPTION_IF(std::find(multisig_signers.begin(), multisig_signers.end(), local_signer) == multisig_signers.end(), error::invalid_multisig_seed);
rct::key skey = rct::zero();
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);
@ -4758,6 +4754,8 @@ void wallet2::generate(const std::string& wallet_, const epee::wipeable_string&
m_multisig = true;
m_multisig_threshold = threshold;
m_multisig_signers = multisig_signers;
// wallet is assumed already finalized
m_multisig_rounds_passed = multisig::multisig_setup_rounds_required(m_multisig_signers.size(), m_multisig_threshold);
setup_keys(password);
create_keys_file(wallet_, false, password, m_nettype != MAINNET || create_address_file);
@ -5208,7 +5206,7 @@ bool wallet2::multisig(bool *ready, uint32_t *threshold, uint32_t *total) const
if (ready)
{
*ready = !(get_account().get_keys().m_account_address.m_spend_public_key == rct::rct2pk(rct::identity())) &&
(m_multisig_rounds_passed == multisig::multisig_kex_rounds_required(m_multisig_signers.size(), m_multisig_threshold) + 1);
(m_multisig_rounds_passed == multisig::multisig_setup_rounds_required(m_multisig_signers.size(), m_multisig_threshold));
}
return true;
}

View file

@ -794,7 +794,8 @@ private:
};
/*!
* \brief Generates a wallet or restores one.
* \brief Generates a wallet or restores one. Assumes the multisig setup
* has already completed for the provided multisig info.
* \param wallet_ Name of wallet file
* \param password Password of wallet file
* \param multisig_data The multisig restore info and keys

View file

@ -171,7 +171,7 @@ static void make_wallets(std::vector<tools::wallet2>& wallets, unsigned int M)
{
ASSERT_TRUE(wallets.size() > 1 && wallets.size() <= KEYS_COUNT);
ASSERT_TRUE(M <= wallets.size());
std::uint32_t total_rounds_required = multisig::multisig_kex_rounds_required(wallets.size(), M) + 1;
std::uint32_t total_rounds_required = multisig::multisig_setup_rounds_required(wallets.size(), M);
std::uint32_t rounds_complete{0};
// initialize wallets, get first round multisig kex msgs