refactor: Use Span of std::byte in CExtKey::SetSeed

Author: MarcoFalke

src/key.cpp

@@ -340,11 +340,11 @@ bool CExtKey::Derive(CExtKey &out, unsigned int _nChild) const {
     return key.Derive(out.key, out.chaincode, _nChild, chaincode);
 }
 
-void CExtKey::SetSeed(Span<const uint8_t> seed)
+void CExtKey::SetSeed(Span<const std::byte> seed)
 {
     static const unsigned char hashkey[] = {'B','i','t','c','o','i','n',' ','s','e','e','d'};
     std::vector<unsigned char, secure_allocator<unsigned char>> vout(64);
-    CHMAC_SHA512{hashkey, sizeof(hashkey)}.Write(seed.data(), seed.size()).Finalize(vout.data());
+    CHMAC_SHA512{hashkey, sizeof(hashkey)}.Write(UCharCast(seed.data()), seed.size()).Finalize(vout.data());
     key.Set(vout.data(), vout.data() + 32, true);
     memcpy(chaincode.begin(), vout.data() + 32, 32);
     nDepth = 0;

src/key.h

@@ -85,7 +85,7 @@ class CKey
 
     //! Simple read-only vector-like interface.
     unsigned int size() const { return (fValid ? keydata.size() : 0); }
-    const unsigned char* data() const { return keydata.data(); }
+    const std::byte* data() const { return reinterpret_cast<const std::byte*>(keydata.data()); }
     const unsigned char* begin() const { return keydata.data(); }
     const unsigned char* end() const { return keydata.data() + size(); }
 
@@ -178,7 +178,7 @@ struct CExtKey {
     void Decode(const unsigned char code[BIP32_EXTKEY_SIZE]);
     bool Derive(CExtKey& out, unsigned int nChild) const;
     CExtPubKey Neuter() const;
-    void SetSeed(Span<const uint8_t> seed);
+    void SetSeed(Span<const std::byte> seed);
 };
 
 /** Initialize the elliptic curve support. May not be called twice without calling ECC_Stop first. */

src/test/bip32_tests.cpp

@@ -120,8 +120,9 @@ const std::vector<std::string> TEST5 = {
     "xprv9s21ZrQH143K3QTDL4LXw2F7HEK3wJUD2nW2nRk4stbPy6cq3jPPqjiChkVvvNKmPGJxWUtg6LnF5kejMRNNU3TGtRBeJgk33yuGBxrMPHL"
 };
 
-void RunTest(const TestVector &test) {
-    std::vector<unsigned char> seed = ParseHex(test.strHexMaster);
+void RunTest(const TestVector& test)
+{
+    std::vector<std::byte> seed{ParseHex<std::byte>(test.strHexMaster)};
     CExtKey key;
     CExtPubKey pubkey;
     key.SetSeed(seed);

src/test/key_io_tests.cpp

@@ -35,7 +35,7 @@ BOOST_AUTO_TEST_CASE(key_io_valid_parse)
             continue;
         }
         std::string exp_base58string = test[0].get_str();
-        std::vector<unsigned char> exp_payload = ParseHex(test[1].get_str());
+        const std::vector<std::byte> exp_payload{ParseHex<std::byte>(test[1].get_str())};
         const UniValue &metadata = test[2].get_obj();
         bool isPrivkey = find_value(metadata, "isPrivkey").get_bool();
         SelectParams(find_value(metadata, "chain").get_str());