add bip32 pubkey serialization

CExtPubKey should be serializable like CPubKey

src/base58.h

@@ -211,7 +211,7 @@ public:
     CBitcoinExtKeyBase() {}
 };
 
-typedef CBitcoinExtKeyBase<CExtKey, 74, CChainParams::EXT_SECRET_KEY> CBitcoinExtKey;
-typedef CBitcoinExtKeyBase<CExtPubKey, 74, CChainParams::EXT_PUBLIC_KEY> CBitcoinExtPubKey;
+typedef CBitcoinExtKeyBase<CExtKey, BIP32_EXTKEY_SIZE, CChainParams::EXT_SECRET_KEY> CBitcoinExtKey;
+typedef CBitcoinExtKeyBase<CExtPubKey, BIP32_EXTKEY_SIZE, CChainParams::EXT_PUBLIC_KEY> CBitcoinExtPubKey;
 
 #endif // BITCOIN_BASE58_H

src/key.cpp

@@ -307,7 +307,7 @@ CExtPubKey CExtKey::Neuter() const {
     return ret;
 }
 
-void CExtKey::Encode(unsigned char code[74]) const {
+void CExtKey::Encode(unsigned char code[BIP32_EXTKEY_SIZE]) const {
     code[0] = nDepth;
     memcpy(code+1, vchFingerprint, 4);
     code[5] = (nChild >> 24) & 0xFF; code[6] = (nChild >> 16) & 0xFF;
@@ -318,12 +318,12 @@ void CExtKey::Encode(unsigned char code[74]) const {
     memcpy(code+42, key.begin(), 32);
 }
 
-void CExtKey::Decode(const unsigned char code[74]) {
+void CExtKey::Decode(const unsigned char 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+74, true);
+    key.Set(code+42, code+BIP32_EXTKEY_SIZE, true);
 }
 
 bool ECC_InitSanityCheck() {

src/key.h

@@ -170,11 +170,28 @@ struct CExtKey {
                a.chaincode == b.chaincode && a.key == b.key;
     }
 
-    void Encode(unsigned char code[74]) const;
-    void Decode(const unsigned char code[74]);
+    void Encode(unsigned char code[BIP32_EXTKEY_SIZE]) const;
+    void Decode(const unsigned char code[BIP32_EXTKEY_SIZE]);
     bool Derive(CExtKey& out, unsigned int nChild) const;
     CExtPubKey Neuter() const;
     void SetMaster(const unsigned char* seed, unsigned int nSeedLen);
+    template <typename Stream>
+    void Serialize(Stream& s, int nType, int nVersion) const
+    {
+        unsigned int len = BIP32_EXTKEY_SIZE;
+        ::WriteCompactSize(s, len);
+        unsigned char code[BIP32_EXTKEY_SIZE];
+        Encode(code);
+        s.write((const char *)&code[0], len);
+    }
+    template <typename Stream>
+    void Unserialize(Stream& s, int nType, int nVersion)
+    {
+        unsigned int len = ::ReadCompactSize(s);
+        unsigned char code[BIP32_EXTKEY_SIZE];
+        s.read((char *)&code[0], len);
+        Decode(code);
+    }
 };
 
 /** Initialize the elliptic curve support. May not be called twice without calling ECC_Stop first. */

src/pubkey.cpp

@@ -98,7 +98,7 @@ bool CPubKey::Derive(CPubKey& pubkeyChild, ChainCode &ccChild, unsigned int nChi
     return true;
 }
 
-void CExtPubKey::Encode(unsigned char code[74]) const {
+void CExtPubKey::Encode(unsigned char code[BIP32_EXTKEY_SIZE]) const {
     code[0] = nDepth;
     memcpy(code+1, vchFingerprint, 4);
     code[5] = (nChild >> 24) & 0xFF; code[6] = (nChild >> 16) & 0xFF;
@@ -108,12 +108,12 @@ void CExtPubKey::Encode(unsigned char code[74]) const {
     memcpy(code+41, pubkey.begin(), CPubKey::COMPRESSED_PUBLIC_KEY_SIZE);
 }
 
-void CExtPubKey::Decode(const unsigned char code[74]) {
+void CExtPubKey::Decode(const unsigned char 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);
-    pubkey.Set(code+41, code+74);
+    pubkey.Set(code+41, code+BIP32_EXTKEY_SIZE);
 }
 
 bool CExtPubKey::Derive(CExtPubKey &out, unsigned int nChild) const {

src/pubkey.h

@@ -14,6 +14,8 @@
 #include <stdexcept>
 #include <vector>
 
+const unsigned int BIP32_EXTKEY_SIZE = 74;
+
 /** A reference to a CKey: the Hash160 of its serialized public key */
 class CKeyID : public uint160
 {
@@ -212,9 +214,33 @@ struct CExtPubKey {
                a.chaincode == b.chaincode && a.pubkey == b.pubkey;
     }
 
-    void Encode(unsigned char code[74]) const;
-    void Decode(const unsigned char code[74]);
+    void Encode(unsigned char code[BIP32_EXTKEY_SIZE]) const;
+    void Decode(const unsigned char code[BIP32_EXTKEY_SIZE]);
     bool Derive(CExtPubKey& out, unsigned int nChild) const;
+
+    unsigned int GetSerializeSize(int nType, int nVersion) const
+    {
+        return BIP32_EXTKEY_SIZE+1; //add one byte for the size (compact int)
+    }
+    template <typename Stream>
+    void Serialize(Stream& s, int nType, int nVersion) const
+    {
+        unsigned int len = BIP32_EXTKEY_SIZE;
+        ::WriteCompactSize(s, len);
+        unsigned char code[BIP32_EXTKEY_SIZE];
+        Encode(code);
+        s.write((const char *)&code[0], len);
+    }
+    template <typename Stream>
+    void Unserialize(Stream& s, int nType, int nVersion)
+    {
+        unsigned int len = ::ReadCompactSize(s);
+        unsigned char code[BIP32_EXTKEY_SIZE];
+        if (len != BIP32_EXTKEY_SIZE)
+            throw std::runtime_error("Invalid extended key size\n");
+        s.read((char *)&code[0], len);
+        Decode(code);
+    }
 };
 
 /** Users of this module must hold an ECCVerifyHandle. The constructor and

src/test/bip32_tests.cpp

@@ -117,6 +117,22 @@ void RunTest(const TestVector &test) {
         }
         key = keyNew;
         pubkey = pubkeyNew;
+
+        CDataStream ssPub(SER_DISK, CLIENT_VERSION);
+        ssPub << pubkeyNew;
+        BOOST_CHECK(ssPub.size() == 75);
+
+        CDataStream ssPriv(SER_DISK, CLIENT_VERSION);
+        ssPriv << keyNew;
+        BOOST_CHECK(ssPriv.size() == 75);
+
+        CExtPubKey pubCheck;
+        CExtKey privCheck;
+        ssPub >> pubCheck;
+        ssPriv >> privCheck;
+
+        BOOST_CHECK(pubCheck == pubkeyNew);
+        BOOST_CHECK(privCheck == keyNew);
     }
 }