[Wallet] split the keypool in an internal and external part
[bitcoinplatinum.git] / src / merkleblock.h
blob73cbf670ee9c87c48e373a4e7f80505a3cfec489
1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-2016 The Bitcoin Core developers
3 // Distributed under the MIT software license, see the accompanying
4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
6 #ifndef BITCOIN_MERKLEBLOCK_H
7 #define BITCOIN_MERKLEBLOCK_H
9 #include "serialize.h"
10 #include "uint256.h"
11 #include "primitives/block.h"
12 #include "bloom.h"
14 #include <vector>
16 /** Data structure that represents a partial merkle tree.
18 * It represents a subset of the txid's of a known block, in a way that
19 * allows recovery of the list of txid's and the merkle root, in an
20 * authenticated way.
22 * The encoding works as follows: we traverse the tree in depth-first order,
23 * storing a bit for each traversed node, signifying whether the node is the
24 * parent of at least one matched leaf txid (or a matched txid itself). In
25 * case we are at the leaf level, or this bit is 0, its merkle node hash is
26 * stored, and its children are not explorer further. Otherwise, no hash is
27 * stored, but we recurse into both (or the only) child branch. During
28 * decoding, the same depth-first traversal is performed, consuming bits and
29 * hashes as they written during encoding.
31 * The serialization is fixed and provides a hard guarantee about the
32 * encoded size:
34 * SIZE <= 10 + ceil(32.25*N)
36 * Where N represents the number of leaf nodes of the partial tree. N itself
37 * is bounded by:
39 * N <= total_transactions
40 * N <= 1 + matched_transactions*tree_height
42 * The serialization format:
43 * - uint32 total_transactions (4 bytes)
44 * - varint number of hashes (1-3 bytes)
45 * - uint256[] hashes in depth-first order (<= 32*N bytes)
46 * - varint number of bytes of flag bits (1-3 bytes)
47 * - byte[] flag bits, packed per 8 in a byte, least significant bit first (<= 2*N-1 bits)
48 * The size constraints follow from this.
50 class CPartialMerkleTree
52 protected:
53 /** the total number of transactions in the block */
54 unsigned int nTransactions;
56 /** node-is-parent-of-matched-txid bits */
57 std::vector<bool> vBits;
59 /** txids and internal hashes */
60 std::vector<uint256> vHash;
62 /** flag set when encountering invalid data */
63 bool fBad;
65 /** helper function to efficiently calculate the number of nodes at given height in the merkle tree */
66 unsigned int CalcTreeWidth(int height) {
67 return (nTransactions+(1 << height)-1) >> height;
70 /** calculate the hash of a node in the merkle tree (at leaf level: the txid's themselves) */
71 uint256 CalcHash(int height, unsigned int pos, const std::vector<uint256> &vTxid);
73 /** recursive function that traverses tree nodes, storing the data as bits and hashes */
74 void TraverseAndBuild(int height, unsigned int pos, const std::vector<uint256> &vTxid, const std::vector<bool> &vMatch);
76 /**
77 * recursive function that traverses tree nodes, consuming the bits and hashes produced by TraverseAndBuild.
78 * it returns the hash of the respective node and its respective index.
80 uint256 TraverseAndExtract(int height, unsigned int pos, unsigned int &nBitsUsed, unsigned int &nHashUsed, std::vector<uint256> &vMatch, std::vector<unsigned int> &vnIndex);
82 public:
84 /** serialization implementation */
85 ADD_SERIALIZE_METHODS;
87 template <typename Stream, typename Operation>
88 inline void SerializationOp(Stream& s, Operation ser_action) {
89 READWRITE(nTransactions);
90 READWRITE(vHash);
91 std::vector<unsigned char> vBytes;
92 if (ser_action.ForRead()) {
93 READWRITE(vBytes);
94 CPartialMerkleTree &us = *(const_cast<CPartialMerkleTree*>(this));
95 us.vBits.resize(vBytes.size() * 8);
96 for (unsigned int p = 0; p < us.vBits.size(); p++)
97 us.vBits[p] = (vBytes[p / 8] & (1 << (p % 8))) != 0;
98 us.fBad = false;
99 } else {
100 vBytes.resize((vBits.size()+7)/8);
101 for (unsigned int p = 0; p < vBits.size(); p++)
102 vBytes[p / 8] |= vBits[p] << (p % 8);
103 READWRITE(vBytes);
107 /** Construct a partial merkle tree from a list of transaction ids, and a mask that selects a subset of them */
108 CPartialMerkleTree(const std::vector<uint256> &vTxid, const std::vector<bool> &vMatch);
110 CPartialMerkleTree();
113 * extract the matching txid's represented by this partial merkle tree
114 * and their respective indices within the partial tree.
115 * returns the merkle root, or 0 in case of failure
117 uint256 ExtractMatches(std::vector<uint256> &vMatch, std::vector<unsigned int> &vnIndex);
122 * Used to relay blocks as header + vector<merkle branch>
123 * to filtered nodes.
125 class CMerkleBlock
127 public:
128 /** Public only for unit testing */
129 CBlockHeader header;
130 CPartialMerkleTree txn;
132 public:
133 /** Public only for unit testing and relay testing (not relayed) */
134 std::vector<std::pair<unsigned int, uint256> > vMatchedTxn;
137 * Create from a CBlock, filtering transactions according to filter
138 * Note that this will call IsRelevantAndUpdate on the filter for each transaction,
139 * thus the filter will likely be modified.
141 CMerkleBlock(const CBlock& block, CBloomFilter& filter);
143 // Create from a CBlock, matching the txids in the set
144 CMerkleBlock(const CBlock& block, const std::set<uint256>& txids);
146 CMerkleBlock() {}
148 ADD_SERIALIZE_METHODS;
150 template <typename Stream, typename Operation>
151 inline void SerializationOp(Stream& s, Operation ser_action) {
152 READWRITE(header);
153 READWRITE(txn);
157 #endif // BITCOIN_MERKLEBLOCK_H