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author | Wladimir J. van der Laan <laanwj@gmail.com> | 2018-03-26 17:03:37 +0200 |
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committer | Wladimir J. van der Laan <laanwj@gmail.com> | 2018-03-26 17:10:29 +0200 |
commit | c948dc8f4285e27d8c0f3553d9d427b2a7b01b77 (patch) | |
tree | 63217cda399decdd418c61daace45a3b9091f117 /src | |
parent | ec7dbaa37c233599e9fc68f8284ee85c1261652b (diff) | |
parent | 2fb9c1e6681370478e24a19172ed6d78d95d50d3 (diff) | |
download | bitcoin-c948dc8f4285e27d8c0f3553d9d427b2a7b01b77.tar.xz |
Merge #12699: [wallet] Shuffle transaction inputs before signing
2fb9c1e shuffle selected coins before transaction finalization (Gregory Sanders)
Pull request description:
Currently inputs are ordered based on COutPoint ordering, which while doesn't leak additional internal wallet state, likely further fingerprints the wallet as a Core wallet to observers.
Note: This slightly changed behavior of `fundrawtransaction` in that the newly-appended inputs will now be shuffled rather than in outpoint-order. This does not break API compatibility.
Simple shuffling of the coins being returned will hopefully allow the wallet to blend in a bit more, in lieu of additional data to find what other wallets are doing, or another standard, ala @gmaxwell's suggested of ordering via scriptPubKey.
Tree-SHA512: 70689a6eccf9fa7fc6e3d884f2eba4b482446a1e6128beff7a98f446d0c60f7966c5a6c55e9b0b3d73a9b539ce54889a26c7efe78ab7f34af386d5e4f3fa6df2
Diffstat (limited to 'src')
-rw-r--r-- | src/wallet/wallet.cpp | 37 |
1 files changed, 23 insertions, 14 deletions
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp index b37a411ef4..a80875e7ed 100644 --- a/src/wallet/wallet.cpp +++ b/src/wallet/wallet.cpp @@ -2890,20 +2890,11 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CTransac nChangePosInOut = -1; } - // Fill vin + // Dummy fill vin for maximum size estimation // - // Note how the sequence number is set to non-maxint so that - // the nLockTime set above actually works. - // - // BIP125 defines opt-in RBF as any nSequence < maxint-1, so - // we use the highest possible value in that range (maxint-2) - // to avoid conflicting with other possible uses of nSequence, - // and in the spirit of "smallest possible change from prior - // behavior." - const uint32_t nSequence = coin_control.signalRbf ? MAX_BIP125_RBF_SEQUENCE : (CTxIn::SEQUENCE_FINAL - 1); - for (const auto& coin : setCoins) - txNew.vin.push_back(CTxIn(coin.outpoint,CScript(), - nSequence)); + for (const auto& coin : setCoins) { + txNew.vin.push_back(CTxIn(coin.outpoint,CScript())); + } nBytes = CalculateMaximumSignedTxSize(txNew, this); if (nBytes < 0) { @@ -2993,11 +2984,29 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CTransac if (nChangePosInOut == -1) reservekey.ReturnKey(); // Return any reserved key if we don't have change + // Shuffle selected coins and fill in final vin + txNew.vin.clear(); + std::vector<CInputCoin> selected_coins(setCoins.begin(), setCoins.end()); + std::shuffle(selected_coins.begin(), selected_coins.end(), FastRandomContext()); + + // Note how the sequence number is set to non-maxint so that + // the nLockTime set above actually works. + // + // BIP125 defines opt-in RBF as any nSequence < maxint-1, so + // we use the highest possible value in that range (maxint-2) + // to avoid conflicting with other possible uses of nSequence, + // and in the spirit of "smallest possible change from prior + // behavior." + const uint32_t nSequence = coin_control.signalRbf ? MAX_BIP125_RBF_SEQUENCE : (CTxIn::SEQUENCE_FINAL - 1); + for (const auto& coin : selected_coins) { + txNew.vin.push_back(CTxIn(coin.outpoint, CScript(), nSequence)); + } + if (sign) { CTransaction txNewConst(txNew); int nIn = 0; - for (const auto& coin : setCoins) + for (const auto& coin : selected_coins) { const CScript& scriptPubKey = coin.txout.scriptPubKey; SignatureData sigdata; |