Merge branch 'beta' into mergemaster

# Conflicts:
#	src/main.cpp

src/paymentdisclosure.cpp

@@ -0,0 +1,63 @@
+// Copyright (c) 2017 The Zcash developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include "paymentdisclosure.h"
+#include "util.h"
+
+std::string PaymentDisclosureInfo::ToString() const {
+    return strprintf("PaymentDisclosureInfo(version=%d, esk=%s, joinSplitPrivKey=<omitted>, address=%s)",
+        version, esk.ToString(), CZCPaymentAddress(zaddr).ToString());
+}
+
+std::string PaymentDisclosure::ToString() const {
+    std::string s = HexStr(payloadSig.begin(), payloadSig.end());
+    return strprintf("PaymentDisclosure(payload=%s, payloadSig=%s)", payload.ToString(), s);
+}
+
+std::string PaymentDisclosurePayload::ToString() const {
+    return strprintf("PaymentDisclosurePayload(version=%d, esk=%s, txid=%s, js=%d, n=%d, address=%s, message=%s)",
+        version, esk.ToString(), txid.ToString(), js, n, CZCPaymentAddress(zaddr).ToString(), message);
+}
+
+PaymentDisclosure::PaymentDisclosure(const uint256 &joinSplitPubKey, const PaymentDisclosureKey &key, const PaymentDisclosureInfo &info, const std::string &message)
+{
+    // Populate payload member variable
+    payload.version = info.version; // experimental = 0, production = 1 etc.
+    payload.esk = info.esk;
+    payload.txid = key.hash;
+    payload.js = key.js;
+    payload.n = key.n;
+    payload.zaddr = info.zaddr;
+    payload.message = message;
+
+    // Serialize and hash the payload to generate a signature
+    uint256 dataToBeSigned = SerializeHash(payload, SER_GETHASH, 0);
+
+    LogPrint("paymentdisclosure", "Payment Disclosure: signing raw payload = %s\n", dataToBeSigned.ToString());
+
+    // Prepare buffer to store ed25519 key pair in libsodium-compatible format
+    unsigned char bufferKeyPair[64];
+    memcpy(&bufferKeyPair[0], info.joinSplitPrivKey.begin(), 32);
+    memcpy(&bufferKeyPair[32], joinSplitPubKey.begin(), 32);
+
+    // Compute payload signature member variable
+    if (!(crypto_sign_detached(payloadSig.data(), NULL,
+                               dataToBeSigned.begin(), 32,
+                               &bufferKeyPair[0]
+                               ) == 0))
+    {
+        throw std::runtime_error("crypto_sign_detached failed");
+    }
+
+    // Sanity check
+    if (!(crypto_sign_verify_detached(payloadSig.data(),
+                                      dataToBeSigned.begin(), 32,
+                                      joinSplitPubKey.begin()) == 0))
+    {
+        throw std::runtime_error("crypto_sign_verify_detached failed");
+    }
+
+    std::string sigString = HexStr(payloadSig.data(), payloadSig.data() + payloadSig.size());
+    LogPrint("paymentdisclosure", "Payment Disclosure: signature = %s\n", sigString);
+}