Method Derive

src/pubkey.cpp:227–246

}

bool CPubKey::Derive(CPubKey& pubkeyChild, ChainCode &ccChild, unsigned int nChild, const ChainCode& cc) const {
    assert(IsValid());
    assert((nChild >> 31) == 0);
    assert(size() == COMPRESSED_PUBLIC_KEY_SIZE);
    unsigned char out[64];
    BIP32Hash(cc, nChild, *begin(), begin()+1, out);
    memcpy(ccChild.begin(), out+32, 32);
    secp256k1_pubkey pubkey;
    if (!secp256k1_ec_pubkey_parse(secp256k1_context_verify, &pubkey, vch, size())) {
        return false;
    }
    if (!secp256k1_ec_pubkey_tweak_add(secp256k1_context_verify, &pubkey, out)) {
        return false;
    }
    unsigned char pub[COMPRESSED_PUBLIC_KEY_SIZE];
    size_t publen = COMPRESSED_PUBLIC_KEY_SIZE;
    secp256k1_ec_pubkey_serialize(secp256k1_context_verify, pub, &publen, &pubkey, SECP256K1_EC_COMPRESSED);
    pubkeyChild.Set(pub, pub + publen);
    return true;
}

void CExtPubKey::Encode(unsigned char code[BIP32_EXTKEY_SIZE]) const {
    code[0] = nDepth;