From f1ef7f0aa46338f4cd8de79696027a1bf868f359 Mon Sep 17 00:00:00 2001 From: Andrew Chow Date: Tue, 15 Oct 2019 17:15:22 -0400 Subject: [PATCH 1/2] Don't calculate tx fees for PSBTs with invalid money values In decodepsbt if an invalid amount is seen, don't calculate the fee but still show the invalid value in the decode. In analyze psbt, if an invalid amount is seen, set the next step to be the creator as the creator needs to remake the transaction so that it is valid. --- src/node/psbt.cpp | 12 ++++++++++++ src/rpc/rawtransaction.cpp | 22 +++++++++++++++++++--- test/functional/rpc_psbt.py | 9 +++++++++ 3 files changed, 40 insertions(+), 3 deletions(-) diff --git a/src/node/psbt.cpp b/src/node/psbt.cpp index 9a30c3f083..69fb1a28a9 100644 --- a/src/node/psbt.cpp +++ b/src/node/psbt.cpp @@ -2,6 +2,7 @@ // Distributed under the MIT software license, see the accompanying // file COPYING or http://www.opensource.org/licenses/mit-license.php. +#include #include #include #include @@ -31,6 +32,10 @@ PSBTAnalysis AnalyzePSBT(PartiallySignedTransaction psbtx) // Check for a UTXO CTxOut utxo; if (psbtx.GetInputUTXO(utxo, i)) { + if (!MoneyRange(utxo.nValue) || !MoneyRange(in_amt + utxo.nValue)) { + result.SetInvalid(strprintf("PSBT is not valid. Input %u has invalid value", i)); + return result; + } in_amt += utxo.nValue; input_analysis.has_utxo = true; } else { @@ -85,9 +90,16 @@ PSBTAnalysis AnalyzePSBT(PartiallySignedTransaction psbtx) // Get the output amount CAmount out_amt = std::accumulate(psbtx.tx->vout.begin(), psbtx.tx->vout.end(), CAmount(0), [](CAmount a, const CTxOut& b) { + if (!MoneyRange(a) || !MoneyRange(b.nValue) || !MoneyRange(a + b.nValue)) { + return CAmount(-1); + } return a += b.nValue; } ); + if (!MoneyRange(out_amt)) { + result.SetInvalid(strprintf("PSBT is not valid. Output amount invalid")); + return result; + } // Get the fee CAmount fee = in_amt - out_amt; diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp index 6a02984a0e..67235a6942 100644 --- a/src/rpc/rawtransaction.cpp +++ b/src/rpc/rawtransaction.cpp @@ -1077,7 +1077,12 @@ UniValue decodepsbt(const JSONRPCRequest& request) UniValue out(UniValue::VOBJ); out.pushKV("amount", ValueFromAmount(txout.nValue)); - total_in += txout.nValue; + if (MoneyRange(txout.nValue) && MoneyRange(total_in + txout.nValue)) { + total_in += txout.nValue; + } else { + // Hack to just not show fee later + have_all_utxos = false; + } UniValue o(UniValue::VOBJ); ScriptToUniv(txout.scriptPubKey, o, true); @@ -1087,7 +1092,13 @@ UniValue decodepsbt(const JSONRPCRequest& request) UniValue non_wit(UniValue::VOBJ); TxToUniv(*input.non_witness_utxo, uint256(), non_wit, false); in.pushKV("non_witness_utxo", non_wit); - total_in += input.non_witness_utxo->vout[psbtx.tx->vin[i].prevout.n].nValue; + CAmount utxo_val = input.non_witness_utxo->vout[psbtx.tx->vin[i].prevout.n].nValue; + if (MoneyRange(utxo_val) && MoneyRange(total_in + utxo_val)) { + total_in += utxo_val; + } else { + // Hack to just not show fee later + have_all_utxos = false; + } } else { have_all_utxos = false; } @@ -1203,7 +1214,12 @@ UniValue decodepsbt(const JSONRPCRequest& request) outputs.push_back(out); // Fee calculation - output_value += psbtx.tx->vout[i].nValue; + if (MoneyRange(psbtx.tx->vout[i].nValue) && MoneyRange(output_value + psbtx.tx->vout[i].nValue)) { + output_value += psbtx.tx->vout[i].nValue; + } else { + // Hack to just not show fee later + have_all_utxos = false; + } } result.pushKV("outputs", outputs); if (have_all_utxos) { diff --git a/test/functional/rpc_psbt.py b/test/functional/rpc_psbt.py index 2cc9650cb2..5986f197e1 100755 --- a/test/functional/rpc_psbt.py +++ b/test/functional/rpc_psbt.py @@ -422,5 +422,14 @@ class PSBTTest(BitcoinTestFramework): assert_equal(analysis['next'], 'creator') assert_equal(analysis['error'], 'PSBT is not valid. Input 0 spends unspendable output') + self.log.info("PSBT with invalid values should have error message and Creator as next") + analysis = self.nodes[0].analyzepsbt('cHNidP8BAHECAAAAAfA00BFgAm6tp86RowwH6BMImQNL5zXUcTT97XoLGz0BAAAAAAD/////AgD5ApUAAAAAFgAUKNw0x8HRctAgmvoevm4u1SbN7XL87QKVAAAAABYAFPck4gF7iL4NL4wtfRAKgQbghiTUAAAAAAABAR8AgIFq49AHABYAFJUDtxf2PHo641HEOBOAIvFMNTr2AAAA') + assert_equal(analysis['next'], 'creator') + assert_equal(analysis['error'], 'PSBT is not valid. Input 0 has invalid value') + + analysis = self.nodes[0].analyzepsbt('cHNidP8BAHECAAAAAfA00BFgAm6tp86RowwH6BMImQNL5zXUcTT97XoLGz0BAAAAAAD/////AgCAgWrj0AcAFgAUKNw0x8HRctAgmvoevm4u1SbN7XL87QKVAAAAABYAFPck4gF7iL4NL4wtfRAKgQbghiTUAAAAAAABAR8A8gUqAQAAABYAFJUDtxf2PHo641HEOBOAIvFMNTr2AAAA') + assert_equal(analysis['next'], 'creator') + assert_equal(analysis['error'], 'PSBT is not valid. Output amount invalid') + if __name__ == '__main__': PSBTTest().main() From deaa6dd144f5650b385658a0c4f9a014aff8dde2 Mon Sep 17 00:00:00 2001 From: Andrew Chow Date: Tue, 15 Oct 2019 17:26:46 -0400 Subject: [PATCH 2/2] psbt: check output index is within bounds before accessing --- src/node/psbt.cpp | 4 ++++ src/psbt.cpp | 8 +++++++- src/wallet/psbtwallet.cpp | 3 +++ src/wallet/test/psbt_wallet_tests.cpp | 9 +++++++++ test/functional/rpc_psbt.py | 6 ++++++ 5 files changed, 29 insertions(+), 1 deletion(-) diff --git a/src/node/psbt.cpp b/src/node/psbt.cpp index 69fb1a28a9..ff7a38e40d 100644 --- a/src/node/psbt.cpp +++ b/src/node/psbt.cpp @@ -39,6 +39,10 @@ PSBTAnalysis AnalyzePSBT(PartiallySignedTransaction psbtx) in_amt += utxo.nValue; input_analysis.has_utxo = true; } else { + if (input.non_witness_utxo && psbtx.tx->vin[i].prevout.n >= input.non_witness_utxo->vout.size()) { + result.SetInvalid(strprintf("PSBT is not valid. Input %u specifies invalid prevout", i)); + return result; + } input_analysis.has_utxo = false; input_analysis.is_final = false; input_analysis.next = PSBTRole::UPDATER; diff --git a/src/psbt.cpp b/src/psbt.cpp index 9ede62efdf..ed32465872 100644 --- a/src/psbt.cpp +++ b/src/psbt.cpp @@ -66,8 +66,11 @@ bool PartiallySignedTransaction::AddOutput(const CTxOut& txout, const PSBTOutput bool PartiallySignedTransaction::GetInputUTXO(CTxOut& utxo, int input_index) const { PSBTInput input = inputs[input_index]; - int prevout_index = tx->vin[input_index].prevout.n; + uint32_t prevout_index = tx->vin[input_index].prevout.n; if (input.non_witness_utxo) { + if (prevout_index >= input.non_witness_utxo->vout.size()) { + return false; + } utxo = input.non_witness_utxo->vout[prevout_index]; } else if (!input.witness_utxo.IsNull()) { utxo = input.witness_utxo; @@ -255,6 +258,9 @@ bool SignPSBTInput(const SigningProvider& provider, PartiallySignedTransaction& if (input.non_witness_utxo) { // If we're taking our information from a non-witness UTXO, verify that it matches the prevout. COutPoint prevout = tx.vin[index].prevout; + if (prevout.n >= input.non_witness_utxo->vout.size()) { + return false; + } if (input.non_witness_utxo->GetHash() != prevout.hash) { return false; } diff --git a/src/wallet/psbtwallet.cpp b/src/wallet/psbtwallet.cpp index 96c1ad8d3f..3e6386a63f 100644 --- a/src/wallet/psbtwallet.cpp +++ b/src/wallet/psbtwallet.cpp @@ -44,6 +44,9 @@ TransactionError FillPSBT(const CWallet* pwallet, PartiallySignedTransaction& ps if (!input.witness_utxo.IsNull()) { script = input.witness_utxo.scriptPubKey; } else if (input.non_witness_utxo) { + if (txin.prevout.n >= input.non_witness_utxo->vout.size()) { + return TransactionError::MISSING_INPUTS; + } script = input.non_witness_utxo->vout[txin.prevout.n].scriptPubKey; } else { // There's no UTXO so we can just skip this now diff --git a/src/wallet/test/psbt_wallet_tests.cpp b/src/wallet/test/psbt_wallet_tests.cpp index d930ca6bea..5368842ff5 100644 --- a/src/wallet/test/psbt_wallet_tests.cpp +++ b/src/wallet/test/psbt_wallet_tests.cpp @@ -68,6 +68,15 @@ BOOST_AUTO_TEST_CASE(psbt_updater_test) ssTx << psbtx; std::string final_hex = HexStr(ssTx.begin(), ssTx.end()); BOOST_CHECK_EQUAL(final_hex, "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"); + + // Mutate the transaction so that one of the inputs is invalid + psbtx.tx->vin[0].prevout.n = 2; + + // Try to sign the mutated input + SignatureData sigdata; + psbtx.inputs[0].FillSignatureData(sigdata); + const SigningProvider* provider = m_wallet.GetSigningProvider(ws1, sigdata); + BOOST_CHECK(!SignPSBTInput(*provider, psbtx, 0, SIGHASH_ALL)); } BOOST_AUTO_TEST_CASE(parse_hd_keypath) diff --git a/test/functional/rpc_psbt.py b/test/functional/rpc_psbt.py index 5986f197e1..33af819d34 100755 --- a/test/functional/rpc_psbt.py +++ b/test/functional/rpc_psbt.py @@ -431,5 +431,11 @@ class PSBTTest(BitcoinTestFramework): assert_equal(analysis['next'], 'creator') assert_equal(analysis['error'], 'PSBT is not valid. Output amount invalid') + analysis = self.nodes[0].analyzepsbt('cHNidP8BAJoCAAAAAkvEW8NnDtdNtDpsmze+Ht2LH35IJcKv00jKAlUs21RrAwAAAAD/////S8Rbw2cO1020OmybN74e3Ysffkglwq/TSMoCVSzbVGsBAAAAAP7///8CwLYClQAAAAAWABSNJKzjaUb3uOxixsvh1GGE3fW7zQD5ApUAAAAAFgAUKNw0x8HRctAgmvoevm4u1SbN7XIAAAAAAAEAnQIAAAACczMa321tVHuN4GKWKRncycI22aX3uXgwSFUKM2orjRsBAAAAAP7///9zMxrfbW1Ue43gYpYpGdzJwjbZpfe5eDBIVQozaiuNGwAAAAAA/v///wIA+QKVAAAAABl2qRT9zXUVA8Ls5iVqynLHe5/vSe1XyYisQM0ClQAAAAAWABRmWQUcjSjghQ8/uH4Bn/zkakwLtAAAAAAAAQEfQM0ClQAAAAAWABRmWQUcjSjghQ8/uH4Bn/zkakwLtAAAAA==') + assert_equal(analysis['next'], 'creator') + assert_equal(analysis['error'], 'PSBT is not valid. Input 0 specifies invalid prevout') + + assert_raises_rpc_error(-25, 'Missing inputs', self.nodes[0].walletprocesspsbt, 'cHNidP8BAJoCAAAAAkvEW8NnDtdNtDpsmze+Ht2LH35IJcKv00jKAlUs21RrAwAAAAD/////S8Rbw2cO1020OmybN74e3Ysffkglwq/TSMoCVSzbVGsBAAAAAP7///8CwLYClQAAAAAWABSNJKzjaUb3uOxixsvh1GGE3fW7zQD5ApUAAAAAFgAUKNw0x8HRctAgmvoevm4u1SbN7XIAAAAAAAEAnQIAAAACczMa321tVHuN4GKWKRncycI22aX3uXgwSFUKM2orjRsBAAAAAP7///9zMxrfbW1Ue43gYpYpGdzJwjbZpfe5eDBIVQozaiuNGwAAAAAA/v///wIA+QKVAAAAABl2qRT9zXUVA8Ls5iVqynLHe5/vSe1XyYisQM0ClQAAAAAWABRmWQUcjSjghQ8/uH4Bn/zkakwLtAAAAAAAAQEfQM0ClQAAAAAWABRmWQUcjSjghQ8/uH4Bn/zkakwLtAAAAA==') + if __name__ == '__main__': PSBTTest().main()