Add proof of work request for future DDOS mitigation use.

1 files changed, 22 insertions, 0 deletions

diff --git a/node/IncomingPacket.hpp b/node/IncomingPacket.hpp
index 06220c4b..fd7a06c0 100644
--- a/node/IncomingPacket.hpp
+++ b/node/IncomingPacket.hpp
@@ -107,6 +107,27 @@ public:
 	 */
 	inline uint64_t receiveTime() const throw() { return _receiveTime; }
 
+	/**
+	 * Compute the Salsa20/12+SHA512 proof of work function
+	 *
+	 * @param difficulty Difficulty in bits (max: 64)
+	 * @param challenge Challenge string
+	 * @param challengeLength Length of challenge in bytes (max allowed: ZT_PROTO_MAX_PACKET_LENGTH)
+	 * @param result Buffer to fill with 16-byte result
+	 */
+	static void computeSalsa2012Sha512ProofOfWork(unsigned int difficulty,const void *challenge,unsigned int challengeLength,unsigned char result[16]);
+
+	/**
+	 * Verify the result of Salsa20/12+SHA512 proof of work
+	 *
+	 * @param difficulty Difficulty in bits (max: 64)
+	 * @param challenge Challenge bytes
+	 * @param challengeLength Length of challenge in bytes (max allowed: ZT_PROTO_MAX_PACKET_LENGTH)
+	 * @param proposedResult Result supplied by client
+	 * @return True if result is valid
+	 */
+	static bool testSalsa2012Sha512ProofOfWorkResult(unsigned int difficulty,const void *challenge,unsigned int challengeLength,const unsigned char proposedResult[16]);
+
 private:
 	// These are called internally to handle packet contents once it has
 	// been authenticated, decrypted, decompressed, and classified.
@@ -126,6 +147,7 @@ private:
 	bool _doPUSH_DIRECT_PATHS(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer);
 	bool _doCIRCUIT_TEST(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer);
 	bool _doCIRCUIT_TEST_REPORT(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer);
+	bool _doREQUEST_PROOF_OF_WORK(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer);
 
 	// Send an ERROR_NEED_MEMBERSHIP_CERTIFICATE to a peer indicating that an updated cert is needed to communicate
 	void _sendErrorNeedCertificate(const RuntimeEnvironment *RR,const SharedPtr<Peer> &peer,uint64_t nwid);