proof of work bugfix

libwhisper/Message.cpp

@@ -161,24 +161,24 @@ unsigned Envelope::workProved() const
 
 void Envelope::proveWork(unsigned _ms)
 {
-	// PoW
 	h256 d[2];
 	d[0] = sha3(WithoutNonce);
-	uint32_t& n = *(uint32_t*)&(d[1][28]);
 	unsigned bestBitSet = 0;
 	bytesConstRef chuck(d[0].data(), 64);
 
 	chrono::high_resolution_clock::time_point then = chrono::high_resolution_clock::now() + chrono::milliseconds(_ms);
-	for (n = 0; chrono::high_resolution_clock::now() < then; )
+	while (chrono::high_resolution_clock::now() < then)
 		// do it rounds of 1024 for efficiency
-		for (unsigned i = 0; i < 1024; ++i, ++n)
+		for (unsigned i = 0; i < 1024; ++i)
 		{
 			auto fbs = dev::sha3(chuck).firstBitSet();
 			if (fbs > bestBitSet)
 			{
 				bestBitSet = fbs;
-				m_nonce = n;
+				m_nonce = (h256::Arith)d[1];
 			}
+
+			incrementHash(d[1]);
 		}
 }
 

libwhisper/Message.h

@@ -81,6 +81,7 @@ public:
 	void proveWork(unsigned _ms);
 
 	bool matchesBloomFilter(TopicBloomFilterHash const& f) const;
+	static void incrementHash(h256& _h) { for (unsigned i = h256::size; i > 0 && ++_h[--i] > 0; ) {} }
 
 private:
 	Envelope(unsigned _exp, unsigned _ttl, AbridgedTopics const& _topic): m_expiry(_exp), m_ttl(_ttl), m_topic(_topic) {}

test/libwhisper/whisperMessage.cpp

@@ -95,12 +95,18 @@ BOOST_AUTO_TEST_CASE(work)
 	cnote << "Testing proof of work...";
 
 	Secret zero;
-	Topics topics = createRandomTopics(0xDEAD);
-	bytes const payload = createRandomPayload(0xFFFFF);
+	unsigned r = 0xC0DEFEED;
+
+	for (int i = 0; i < 20; ++i)
+	{
+		Topics topics = createRandomTopics(++r);
+		bytes const payload = createRandomPayload(++r);
 		Message m(payload);
 		Envelope e = m.seal(zero, topics, 1, 50);
 		unsigned x = e.workProved();
-	BOOST_REQUIRE(x > 0);
+		cnote << x;
+		BOOST_REQUIRE(x > 4);
+	}
 }
 
 BOOST_AUTO_TEST_SUITE_END()