diff --git a/src/key.cpp b/src/key.cpp
index 457cf199c..d0c28eb56 100644
--- a/src/key.cpp
+++ b/src/key.cpp
@@ -1,418 +1,419 @@
 // Copyright (c) 2009-2016 The Bitcoin Core developers
 // 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 <key.h>
 
 #include <arith_uint256.h>
 #include <crypto/common.h>
 #include <crypto/hmac_sha512.h>
 #include <pubkey.h>
 #include <random.h>
 
 #include <secp256k1.h>
 #include <secp256k1_recovery.h>
 #include <secp256k1_schnorr.h>
 
 static secp256k1_context *secp256k1_context_sign = nullptr;
 
 /**
  * These functions are taken from the libsecp256k1 distribution and are very
  * ugly.
  */
 
 /**
  * This parses a format loosely based on a DER encoding of the ECPrivateKey type
  * from section C.4 of SEC 1 <http://www.secg.org/sec1-v2.pdf>, with the
  * following caveats:
  *
  * * The octet-length of the SEQUENCE must be encoded as 1 or 2 octets. It is
  * not required to be encoded as one octet if it is less than 256, as DER would
  * require.
  * * The octet-length of the SEQUENCE must not be greater than the remaining
  * length of the key encoding, but need not match it (i.e. the encoding may
  * contain junk after the encoded SEQUENCE).
  * * The privateKey OCTET STRING is zero-filled on the left to 32 octets.
  * * Anything after the encoding of the privateKey OCTET STRING is ignored,
  * whether or not it is validly encoded DER.
  *
  * out32 must point to an output buffer of length at least 32 bytes.
  */
 static int ec_privkey_import_der(const secp256k1_context *ctx, uint8_t *out32,
                                  const uint8_t *privkey, size_t privkeylen) {
     const uint8_t *end = privkey + privkeylen;
     memset(out32, 0, 32);
     /* sequence header */
     if (end - privkey < 1 || *privkey != 0x30u) {
         return 0;
     }
     privkey++;
     /* sequence length constructor */
     if (end - privkey < 1 || !(*privkey & 0x80u)) {
         return 0;
     }
     ptrdiff_t lenb = *privkey & ~0x80u;
     privkey++;
     if (lenb < 1 || lenb > 2) {
         return 0;
     }
     if (end - privkey < lenb) {
         return 0;
     }
     /* sequence length */
     ptrdiff_t len =
         privkey[lenb - 1] | (lenb > 1 ? privkey[lenb - 2] << 8 : 0u);
     privkey += lenb;
     if (end - privkey < len) {
         return 0;
     }
     /* sequence element 0: version number (=1) */
     if (end - privkey < 3 || privkey[0] != 0x02u || privkey[1] != 0x01u ||
         privkey[2] != 0x01u) {
         return 0;
     }
     privkey += 3;
     /* sequence element 1: octet string, up to 32 bytes */
     if (end - privkey < 2 || privkey[0] != 0x04u) {
         return 0;
     }
     ptrdiff_t oslen = privkey[1];
     privkey += 2;
     if (oslen > 32 || end - privkey < oslen) {
         return 0;
     }
     memcpy(out32 + (32 - oslen), privkey, oslen);
     if (!secp256k1_ec_seckey_verify(ctx, out32)) {
         memset(out32, 0, 32);
         return 0;
     }
     return 1;
 }
 
 /**
  * This serializes to a DER encoding of the ECPrivateKey type from section C.4
  * of SEC 1 <http://www.secg.org/sec1-v2.pdf>. The optional parameters and
  * publicKey fields are included.
  *
  * privkey must point to an output buffer of length at least
  * CKey::PRIVATE_KEY_SIZE bytes. privkeylen must initially be set to the size of
  * the privkey buffer. Upon return it will be set to the number of bytes used in
  * the buffer. key32 must point to a 32-byte raw private key.
  */
 static int ec_privkey_export_der(const secp256k1_context *ctx, uint8_t *privkey,
                                  size_t *privkeylen, const uint8_t *key32,
                                  int compressed) {
     assert(*privkeylen >= CKey::PRIVATE_KEY_SIZE);
     secp256k1_pubkey pubkey;
     size_t pubkeylen = 0;
     if (!secp256k1_ec_pubkey_create(ctx, &pubkey, key32)) {
         *privkeylen = 0;
         return 0;
     }
 
     if (compressed) {
         static const uint8_t begin[] = {0x30, 0x81, 0xD3, 0x02,
                                         0x01, 0x01, 0x04, 0x20};
         static const uint8_t middle[] = {
             0xA0, 0x81, 0x85, 0x30, 0x81, 0x82, 0x02, 0x01, 0x01, 0x30, 0x2C,
             0x06, 0x07, 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x01, 0x01, 0x02, 0x21,
             0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
             0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
             0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFC, 0x2F,
             0x30, 0x06, 0x04, 0x01, 0x00, 0x04, 0x01, 0x07, 0x04, 0x21, 0x02,
             0x79, 0xBE, 0x66, 0x7E, 0xF9, 0xDC, 0xBB, 0xAC, 0x55, 0xA0, 0x62,
             0x95, 0xCE, 0x87, 0x0B, 0x07, 0x02, 0x9B, 0xFC, 0xDB, 0x2D, 0xCE,
             0x28, 0xD9, 0x59, 0xF2, 0x81, 0x5B, 0x16, 0xF8, 0x17, 0x98, 0x02,
             0x21, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
             0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xBA, 0xAE, 0xDC, 0xE6,
             0xAF, 0x48, 0xA0, 0x3B, 0xBF, 0xD2, 0x5E, 0x8C, 0xD0, 0x36, 0x41,
             0x41, 0x02, 0x01, 0x01, 0xA1, 0x24, 0x03, 0x22, 0x00};
         uint8_t *ptr = privkey;
         memcpy(ptr, begin, sizeof(begin));
         ptr += sizeof(begin);
         memcpy(ptr, key32, 32);
         ptr += 32;
         memcpy(ptr, middle, sizeof(middle));
         ptr += sizeof(middle);
         pubkeylen = CPubKey::COMPRESSED_PUBLIC_KEY_SIZE;
         secp256k1_ec_pubkey_serialize(ctx, ptr, &pubkeylen, &pubkey,
                                       SECP256K1_EC_COMPRESSED);
         ptr += pubkeylen;
         *privkeylen = ptr - privkey;
         assert(*privkeylen == CKey::COMPRESSED_PRIVATE_KEY_SIZE);
     } else {
         static const uint8_t begin[] = {0x30, 0x82, 0x01, 0x13, 0x02,
                                         0x01, 0x01, 0x04, 0x20};
         static const uint8_t middle[] = {
             0xA0, 0x81, 0xA5, 0x30, 0x81, 0xA2, 0x02, 0x01, 0x01, 0x30, 0x2C,
             0x06, 0x07, 0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x01, 0x01, 0x02, 0x21,
             0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
             0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
             0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFC, 0x2F,
             0x30, 0x06, 0x04, 0x01, 0x00, 0x04, 0x01, 0x07, 0x04, 0x41, 0x04,
             0x79, 0xBE, 0x66, 0x7E, 0xF9, 0xDC, 0xBB, 0xAC, 0x55, 0xA0, 0x62,
             0x95, 0xCE, 0x87, 0x0B, 0x07, 0x02, 0x9B, 0xFC, 0xDB, 0x2D, 0xCE,
             0x28, 0xD9, 0x59, 0xF2, 0x81, 0x5B, 0x16, 0xF8, 0x17, 0x98, 0x48,
             0x3A, 0xDA, 0x77, 0x26, 0xA3, 0xC4, 0x65, 0x5D, 0xA4, 0xFB, 0xFC,
             0x0E, 0x11, 0x08, 0xA8, 0xFD, 0x17, 0xB4, 0x48, 0xA6, 0x85, 0x54,
             0x19, 0x9C, 0x47, 0xD0, 0x8F, 0xFB, 0x10, 0xD4, 0xB8, 0x02, 0x21,
             0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
             0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xBA, 0xAE, 0xDC, 0xE6, 0xAF,
             0x48, 0xA0, 0x3B, 0xBF, 0xD2, 0x5E, 0x8C, 0xD0, 0x36, 0x41, 0x41,
             0x02, 0x01, 0x01, 0xA1, 0x44, 0x03, 0x42, 0x00};
         uint8_t *ptr = privkey;
         memcpy(ptr, begin, sizeof(begin));
         ptr += sizeof(begin);
         memcpy(ptr, key32, 32);
         ptr += 32;
         memcpy(ptr, middle, sizeof(middle));
         ptr += sizeof(middle);
         pubkeylen = CPubKey::PUBLIC_KEY_SIZE;
         secp256k1_ec_pubkey_serialize(ctx, ptr, &pubkeylen, &pubkey,
                                       SECP256K1_EC_UNCOMPRESSED);
         ptr += pubkeylen;
         *privkeylen = ptr - privkey;
         assert(*privkeylen == CKey::PRIVATE_KEY_SIZE);
     }
     return 1;
 }
 
 bool CKey::Check(const uint8_t *vch) {
     return secp256k1_ec_seckey_verify(secp256k1_context_sign, vch);
 }
 
 void CKey::MakeNewKey(bool fCompressedIn) {
     do {
         GetStrongRandBytes(keydata.data(), keydata.size());
     } while (!Check(keydata.data()));
     fValid = true;
     fCompressed = fCompressedIn;
 }
 
 CPrivKey CKey::GetPrivKey() const {
     assert(fValid);
     CPrivKey privkey;
     int ret;
     size_t privkeylen;
     privkey.resize(PRIVATE_KEY_SIZE);
     privkeylen = PRIVATE_KEY_SIZE;
     ret = ec_privkey_export_der(
         secp256k1_context_sign, privkey.data(), &privkeylen, begin(),
         fCompressed ? SECP256K1_EC_COMPRESSED : SECP256K1_EC_UNCOMPRESSED);
     assert(ret);
     privkey.resize(privkeylen);
     return privkey;
 }
 
 CPubKey CKey::GetPubKey() const {
     assert(fValid);
     secp256k1_pubkey pubkey;
     size_t clen = CPubKey::PUBLIC_KEY_SIZE;
     CPubKey result;
     int ret =
         secp256k1_ec_pubkey_create(secp256k1_context_sign, &pubkey, begin());
     assert(ret);
     secp256k1_ec_pubkey_serialize(
         secp256k1_context_sign, (uint8_t *)result.begin(), &clen, &pubkey,
         fCompressed ? SECP256K1_EC_COMPRESSED : SECP256K1_EC_UNCOMPRESSED);
     assert(result.size() == clen);
     assert(result.IsValid());
     return result;
 }
 
 bool CKey::SignECDSA(const uint256 &hash, std::vector<uint8_t> &vchSig,
                      uint32_t test_case) const {
     if (!fValid) {
         return false;
     }
     vchSig.resize(CPubKey::SIGNATURE_SIZE);
     size_t nSigLen = CPubKey::SIGNATURE_SIZE;
     uint8_t extra_entropy[32] = {0};
     WriteLE32(extra_entropy, test_case);
     secp256k1_ecdsa_signature sig;
     int ret = secp256k1_ecdsa_sign(secp256k1_context_sign, &sig, hash.begin(),
                                    begin(), secp256k1_nonce_function_rfc6979,
                                    test_case ? extra_entropy : nullptr);
     assert(ret);
     secp256k1_ecdsa_signature_serialize_der(secp256k1_context_sign,
                                             vchSig.data(), &nSigLen, &sig);
     vchSig.resize(nSigLen);
     return true;
 }
 
 bool CKey::SignSchnorr(const uint256 &hash, std::vector<uint8_t> &vchSig,
                        uint32_t test_case) const {
     if (!fValid) {
         return false;
     }
     vchSig.resize(64);
     uint8_t extra_entropy[32] = {0};
     WriteLE32(extra_entropy, test_case);
 
     int ret = secp256k1_schnorr_sign(
         secp256k1_context_sign, &vchSig[0], hash.begin(), begin(),
         secp256k1_nonce_function_rfc6979, test_case ? extra_entropy : nullptr);
     assert(ret);
     return true;
 }
 
 bool CKey::VerifyPubKey(const CPubKey &pubkey) const {
     if (pubkey.IsCompressed() != fCompressed) {
         return false;
     }
     uint8_t rnd[8];
     std::string str = "Bitcoin key verification\n";
     GetRandBytes(rnd, sizeof(rnd));
     uint256 hash;
     CHash256()
         .Write((uint8_t *)str.data(), str.size())
         .Write(rnd, sizeof(rnd))
         .Finalize(hash.begin());
     std::vector<uint8_t> vchSig;
     SignECDSA(hash, vchSig);
     return pubkey.VerifyECDSA(hash, vchSig);
 }
 
 bool CKey::SignCompact(const uint256 &hash,
                        std::vector<uint8_t> &vchSig) const {
     if (!fValid) {
         return false;
     }
     vchSig.resize(CPubKey::COMPACT_SIGNATURE_SIZE);
     int rec = -1;
     secp256k1_ecdsa_recoverable_signature sig;
     int ret = secp256k1_ecdsa_sign_recoverable(
         secp256k1_context_sign, &sig, hash.begin(), begin(),
         secp256k1_nonce_function_rfc6979, nullptr);
     assert(ret);
     secp256k1_ecdsa_recoverable_signature_serialize_compact(
         secp256k1_context_sign, &vchSig[1], &rec, &sig);
     assert(ret);
     assert(rec != -1);
     vchSig[0] = 27 + rec + (fCompressed ? 4 : 0);
     return true;
 }
 
 bool CKey::Load(const CPrivKey &privkey, const CPubKey &vchPubKey,
                 bool fSkipCheck = false) {
     if (!ec_privkey_import_der(secp256k1_context_sign, (uint8_t *)begin(),
-                               privkey.data(), privkey.size()))
+                               privkey.data(), privkey.size())) {
         return false;
+    }
     fCompressed = vchPubKey.IsCompressed();
     fValid = true;
 
     if (fSkipCheck) {
         return true;
     }
 
     return VerifyPubKey(vchPubKey);
 }
 
 bool CKey::Derive(CKey &keyChild, ChainCode &ccChild, unsigned int nChild,
                   const ChainCode &cc) const {
     assert(IsValid());
     assert(IsCompressed());
     std::vector<uint8_t, secure_allocator<uint8_t>> vout(64);
     if ((nChild >> 31) == 0) {
         CPubKey pubkey = GetPubKey();
         assert(pubkey.size() == CPubKey::COMPRESSED_PUBLIC_KEY_SIZE);
         BIP32Hash(cc, nChild, *pubkey.begin(), pubkey.begin() + 1, vout.data());
     } else {
         assert(size() == 32);
         BIP32Hash(cc, nChild, 0, begin(), vout.data());
     }
     memcpy(ccChild.begin(), vout.data() + 32, 32);
     memcpy((uint8_t *)keyChild.begin(), begin(), 32);
     bool ret = secp256k1_ec_privkey_tweak_add(
         secp256k1_context_sign, (uint8_t *)keyChild.begin(), vout.data());
     keyChild.fCompressed = true;
     keyChild.fValid = ret;
     return ret;
 }
 
 bool CExtKey::Derive(CExtKey &out, unsigned int _nChild) const {
     out.nDepth = nDepth + 1;
     CKeyID id = key.GetPubKey().GetID();
     memcpy(&out.vchFingerprint[0], &id, 4);
     out.nChild = _nChild;
     return key.Derive(out.key, out.chaincode, _nChild, chaincode);
 }
 
 void CExtKey::SetSeed(const uint8_t *seed, unsigned int nSeedLen) {
     static const uint8_t hashkey[] = {'B', 'i', 't', 'c', 'o', 'i',
                                       'n', ' ', 's', 'e', 'e', 'd'};
     std::vector<uint8_t, secure_allocator<uint8_t>> vout(64);
     CHMAC_SHA512(hashkey, sizeof(hashkey))
         .Write(seed, nSeedLen)
         .Finalize(vout.data());
     key.Set(vout.data(), vout.data() + 32, true);
     memcpy(chaincode.begin(), vout.data() + 32, 32);
     nDepth = 0;
     nChild = 0;
     memset(vchFingerprint, 0, sizeof(vchFingerprint));
 }
 
 CExtPubKey CExtKey::Neuter() const {
     CExtPubKey ret;
     ret.nDepth = nDepth;
     memcpy(&ret.vchFingerprint[0], &vchFingerprint[0], 4);
     ret.nChild = nChild;
     ret.pubkey = key.GetPubKey();
     ret.chaincode = chaincode;
     return ret;
 }
 
 void CExtKey::Encode(uint8_t code[BIP32_EXTKEY_SIZE]) const {
     code[0] = nDepth;
     memcpy(code + 1, vchFingerprint, 4);
     code[5] = (nChild >> 24) & 0xFF;
     code[6] = (nChild >> 16) & 0xFF;
     code[7] = (nChild >> 8) & 0xFF;
     code[8] = (nChild >> 0) & 0xFF;
     memcpy(code + 9, chaincode.begin(), 32);
     code[41] = 0;
     assert(key.size() == 32);
     memcpy(code + 42, key.begin(), 32);
 }
 
 void CExtKey::Decode(const uint8_t code[BIP32_EXTKEY_SIZE]) {
     nDepth = code[0];
     memcpy(vchFingerprint, code + 1, 4);
     nChild = (code[5] << 24) | (code[6] << 16) | (code[7] << 8) | code[8];
     memcpy(chaincode.begin(), code + 9, 32);
     key.Set(code + 42, code + BIP32_EXTKEY_SIZE, true);
 }
 
 bool ECC_InitSanityCheck() {
     CKey key;
     key.MakeNewKey(true);
     CPubKey pubkey = key.GetPubKey();
     return key.VerifyPubKey(pubkey);
 }
 
 void ECC_Start() {
     assert(secp256k1_context_sign == nullptr);
 
     secp256k1_context *ctx = secp256k1_context_create(SECP256K1_CONTEXT_SIGN);
     assert(ctx != nullptr);
 
     {
         // Pass in a random blinding seed to the secp256k1 context.
         std::vector<uint8_t, secure_allocator<uint8_t>> vseed(32);
         GetRandBytes(vseed.data(), 32);
         bool ret = secp256k1_context_randomize(ctx, vseed.data());
         assert(ret);
     }
 
     secp256k1_context_sign = ctx;
 }
 
 void ECC_Stop() {
     secp256k1_context *ctx = secp256k1_context_sign;
     secp256k1_context_sign = nullptr;
 
     if (ctx) {
         secp256k1_context_destroy(ctx);
     }
 }