wallet: cold wallet transaction signing

This change adds the ability to create a new unsigned transaction
from a watch only wallet, and save it to a file. This file can
then be moved to another computer/VM where a cold wallet may load
it, sign it, and save it. That cold wallet does not need to have
a blockchain nor daemon. The signed transaction file can then be
moved back to the watch only wallet, which can load it and send
it to the daemon.

Two new simplewallet commands to use it:
sign_transfer (on the cold wallet)
submit_transfer (on the watch only wallet)

The transfer command used on a watch only wallet now writes an
unsigned transaction set in a file called 'unsigned_monero_tx'
instead of submitting the tx to the daemon as a normal wallet does.
The signed tx file is called 'signed_monero_tx'.
This commit is contained in:
moneromooo-monero 2016-09-26 23:11:10 +01:00
parent 9872dcbbe3
commit bba6af9064
No known key found for this signature in database
GPG key ID: 686F07454D6CEFC3
7 changed files with 627 additions and 126 deletions

View file

@ -472,10 +472,7 @@ namespace cryptonote
bool construct_tx_and_get_tx_key(const account_keys& sender_account_keys, const std::vector<tx_source_entry>& sources, const std::vector<tx_destination_entry>& destinations, std::vector<uint8_t> extra, transaction& tx, uint64_t unlock_time, crypto::secret_key &tx_key, bool rct)
{
std::vector<rct::key> amount_keys;
tx.vin.clear();
tx.vout.clear();
tx.signatures.clear();
tx.rct_signatures.type = rct::RCTTypeNull;
tx.set_null();
amount_keys.clear();
tx.version = rct ? 2 : 1;
@ -615,6 +612,14 @@ namespace cryptonote
return false;
}
// check for watch only wallet
bool zero_secret_key = true;
for (size_t i = 0; i < sizeof(sender_account_keys.m_spend_secret_key); ++i)
zero_secret_key &= (sender_account_keys.m_spend_secret_key.data[i] == 0);
if (zero_secret_key)
{
LOG_PRINT_L1("Null secret key, skipping signatures");
}
if (tx.version == 1)
{
@ -641,7 +646,8 @@ namespace cryptonote
tx.signatures.push_back(std::vector<crypto::signature>());
std::vector<crypto::signature>& sigs = tx.signatures.back();
sigs.resize(src_entr.outputs.size());
crypto::generate_ring_signature(tx_prefix_hash, boost::get<txin_to_key>(tx.vin[i]).k_image, keys_ptrs, in_contexts[i].in_ephemeral.sec, src_entr.real_output, sigs.data());
if (!zero_secret_key)
crypto::generate_ring_signature(tx_prefix_hash, boost::get<txin_to_key>(tx.vin[i]).k_image, keys_ptrs, in_contexts[i].in_ephemeral.sec, src_entr.real_output, sigs.data());
ss_ring_s << "signatures:" << ENDL;
std::for_each(sigs.begin(), sigs.end(), [&](const crypto::signature& s){ss_ring_s << s << ENDL;});
ss_ring_s << "prefix_hash:" << tx_prefix_hash << ENDL << "in_ephemeral_key: " << in_contexts[i].in_ephemeral.sec << ENDL << "real_output: " << src_entr.real_output;