From d8b4b49667f3eaf5ac16c218aaba2136ece907d8 Mon Sep 17 00:00:00 2001 From: Ashley Holman Date: Sun, 19 Jan 2014 17:59:57 -0600 Subject: [PATCH] Don't store or send side-chain blocks lower than last checkpoint. --- src/main.cpp | 25 ++++++++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-) diff --git a/src/main.cpp b/src/main.cpp index 3ff1fd3a9..857ff5039 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -2154,6 +2154,11 @@ bool AcceptBlock(CBlock& block, CValidationState& state, CDiskBlockPos* dbp) return state.DoS(100, error("AcceptBlock() : rejected by checkpoint lock-in at %d", nHeight), REJECT_CHECKPOINT, "checkpoint mismatch"); + // Don't accept any forks from the main chain prior to last checkpoint + CBlockIndex* pcheckpoint = Checkpoints::GetLastCheckpoint(mapBlockIndex); + if (pcheckpoint && nHeight < pcheckpoint->nHeight) + return state.DoS(100, error("AcceptBlock() : forked chain older than last checkpoint (height %d)", nHeight)); + // Reject block.nVersion=1 blocks when 95% (75% on testnet) of the network has upgraded: if (block.nVersion < 2) { @@ -3025,10 +3030,28 @@ void static ProcessGetData(CNode* pfrom) if (inv.type == MSG_BLOCK || inv.type == MSG_FILTERED_BLOCK) { - // Send block from disk + bool send = false; map::iterator mi = mapBlockIndex.find(inv.hash); if (mi != mapBlockIndex.end()) { + // If the requested block is at a height below our last + // checkpoint, only serve it if it's in the checkpointed chain + int nHeight = mi->second->nHeight; + CBlockIndex* pcheckpoint = Checkpoints::GetLastCheckpoint(mapBlockIndex); + if (pcheckpoint && nHeight < pcheckpoint->nHeight) { + if (!chainActive.Contains(mi->second)) + { + LogPrintf("ProcessGetData(): ignoring request for old block that isn't in the main chain\n"); + } else { + send = true; + } + } else { + send = true; + } + } + if (send) + { + // Send block from disk CBlock block; ReadBlockFromDisk(block, (*mi).second); if (inv.type == MSG_BLOCK)