From 058d4fd480b14bf6ab9d5a7622c97808e357fd3e Mon Sep 17 00:00:00 2001
From: JoelKatz <DavidJoelSchwartz@GMail.com>
Date: Thu, 17 May 2012 00:42:12 -0700
Subject: [PATCH] Class to handle ledger proposals. We need this because
 they're signed and so must be canonicalized.

---
 src/LedgerProposal.cpp | 61 ++++++++++++++++++++++++++++++++++++++++++
 src/LedgerProposal.h   | 48 +++++++++++++++++++++++++++++++++
 2 files changed, 109 insertions(+)
 create mode 100644 src/LedgerProposal.cpp
 create mode 100644 src/LedgerProposal.h

diff --git a/src/LedgerProposal.cpp b/src/LedgerProposal.cpp
new file mode 100644
index 0000000000..dba8532917
--- /dev/null
+++ b/src/LedgerProposal.cpp
@@ -0,0 +1,61 @@
+
+#include "LedgerProposal.h"
+
+#include <boost/make_shared.hpp>
+
+LedgerProposal::LedgerProposal(SerializerIterator& it) : mKey(boost::make_shared<CKey>())
+{
+	if (it.get32() != sProposeMagic)
+		throw std::runtime_error("Not a ledger proposal");
+
+	mPreviousLedger = it.get256();
+	mCurrentHash = it.get256();
+	mPrevHash = it.get256();
+	mProposeSeq = it.get32();
+	if (mKey->SetPubKey(it.getVL()))
+		throw std::runtime_error("Unable to set public key");
+	mSignature = it.getVL(); 
+
+	mPeerID = Serializer::getSHA512Half(mKey->GetPubKey());
+
+	if (!mKey->Verify(getSigningHash(), mSignature))
+		throw std::runtime_error("Ledger proposal invalid");
+}
+
+LedgerProposal::LedgerProposal(CKey::pointer mPrivateKey, const uint256& prevLgr, const uint256& position) :
+	mPreviousLedger(prevLgr), mCurrentHash(position), mProposeSeq(0), mKey(mPrivateKey)
+{
+	mPeerID = Serializer::getSHA512Half(mKey->GetPubKey());
+	if (!mKey->Sign(getSigningHash(), mSignature))
+		throw std::runtime_error("Unable to sign proposal");
+}
+
+LedgerProposal::LedgerProposal(LedgerProposal::pointer previous, const uint256& newp) :
+	mPeerID(previous->mPeerID), mPreviousLedger(previous->mPreviousLedger), mPrevHash(previous->mCurrentHash),
+	mCurrentHash(newp), mProposeSeq(previous->mProposeSeq + 1), mKey(previous->mKey)
+{
+	if (!mKey->Sign(getSigningHash(), mSignature))
+		throw std::runtime_error("Unable to sign proposal");
+}
+
+void LedgerProposal::add(Serializer& s, bool for_signature) const
+{
+	s.add32(sProposeMagic);
+	s.add256(mPreviousLedger);
+	s.add256(mCurrentHash);
+	s.add256(mPrevHash);
+	s.add32(mProposeSeq);
+
+	if (for_signature)
+		return;
+
+	s.addVL(mKey->GetPubKey());
+	s.addVL(mSignature);
+}
+
+uint256 LedgerProposal::getSigningHash() const
+{
+	Serializer s(104);
+	add(s, true);
+	return s.getSHA512Half();
+}
diff --git a/src/LedgerProposal.h b/src/LedgerProposal.h
new file mode 100644
index 0000000000..a36c3a77f9
--- /dev/null
+++ b/src/LedgerProposal.h
@@ -0,0 +1,48 @@
+#ifndef __PROPOSELEDGER__
+#define __PROPOSELEDEGR__
+
+#include <vector>
+
+#include <boost/shared_ptr.hpp>
+
+#include "uint256.h"
+#include "key.h"
+#include "Serializer.h"
+
+class LedgerProposal
+{
+protected:
+
+	uint256 mPeerID, mPreviousLedger, mPrevHash, mCurrentHash;
+	uint32 mProposeSeq;
+	CKey::pointer mKey;
+	std::vector<unsigned char> mSignature;
+//	std::vector<uint256> mAddedTx, mRemovedTx;
+
+	static const uint32 sProposeMagic = 0x50525000; // PRP
+
+public:
+
+	typedef boost::shared_ptr<LedgerProposal> pointer;
+
+	// proposal from peer
+	LedgerProposal(SerializerIterator& it);
+
+	// our first proposal
+	LedgerProposal(CKey::pointer privateKey, const uint256& prevLedger, const uint256& position);
+
+	// our following proposals
+	LedgerProposal(LedgerProposal::pointer previous, const uint256& newPosition);
+
+	void add(Serializer&, bool for_signature) const;
+	uint256 getSigningHash() const;
+
+	const uint256& getPeerID() const		{ return mPeerID; }
+	const uint256& getPrevHash() const		{ return mPrevHash; }
+	const uint256& getCurrentHash() const	{ return mCurrentHash; }
+	const uint256& getPrevLedger() const	{ return mPreviousLedger; }
+	uint32 getProposeSeq() const			{ return mProposeSeq; }
+
+};
+
+#endif