netcraft
/
litecoin
mirror of https://github.com/litecoin-project/litecoin
6
0
Fork 0
Code Issues Projects Releases Wiki Activity

Cache parent xpub inside of BIP32PubkeyProvider

Browse Source 
Optimize Expand by having BIP32PubkeyProvider also cache the parent
(or only) xpub within itself. Since Expand does not provide a read
cache, it is useful to internally cache this xpub to avoid re-deriving
the same xpub.
pull/764/head
Andrew Chow 5 years ago
parent deb791c7ba
commit 09e25071f4
1 changed files with 15 additions and 4 deletions
Show Stats Download Patch File Download Diff File

19
src/script/descriptor.cpp
Unescape View File

@ -165,7 +165,7 @@ public:
* write_cache is the cache to write keys to (if not nullptr)
* Caches are not exclusive but this is not tested. Currently we use them exclusively
*/
virtual bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info, const DescriptorCache* read_cache = nullptr, DescriptorCache* write_cache = nullptr) const = 0;
virtual bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info, const DescriptorCache* read_cache = nullptr, DescriptorCache* write_cache = nullptr) = 0;
/** Whether this represent multiple public keys at different positions. */
virtual bool IsRange() const = 0;
@ -195,7 +195,7 @@ class OriginPubkeyProvider final : public PubkeyProvider
public:
OriginPubkeyProvider(uint32_t exp_index, KeyOriginInfo info, std::unique_ptr<PubkeyProvider> provider) : PubkeyProvider(exp_index), m_origin(std::move(info)), m_provider(std::move(provider)) {}
bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info, const DescriptorCache* read_cache = nullptr, DescriptorCache* write_cache = nullptr) const override
bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info, const DescriptorCache* read_cache = nullptr, DescriptorCache* write_cache = nullptr) override
{
if (!m_provider->GetPubKey(pos, arg, key, info, read_cache, write_cache)) return false;
std::copy(std::begin(m_origin.fingerprint), std::end(m_origin.fingerprint), info.fingerprint);
@ -225,7 +225,7 @@ class ConstPubkeyProvider final : public PubkeyProvider
public:
ConstPubkeyProvider(uint32_t exp_index, const CPubKey& pubkey) : PubkeyProvider(exp_index), m_pubkey(pubkey) {}
bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info, const DescriptorCache* read_cache = nullptr, DescriptorCache* write_cache = nullptr) const override
bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info, const DescriptorCache* read_cache = nullptr, DescriptorCache* write_cache = nullptr) override
{
key = m_pubkey;
info.path.clear();
@ -262,6 +262,9 @@ class BIP32PubkeyProvider final : public PubkeyProvider
CExtPubKey m_root_extkey;
KeyPath m_path;
DeriveType m_derive;
// Cache of the parent of the final derived pubkeys.
// Primarily useful for situations when no read_cache is provided
CExtPubKey m_cached_xpub;
bool GetExtKey(const SigningProvider& arg, CExtKey& ret) const
{
@ -298,7 +301,7 @@ public:
BIP32PubkeyProvider(uint32_t exp_index, const CExtPubKey& extkey, KeyPath path, DeriveType derive) : PubkeyProvider(exp_index), m_root_extkey(extkey), m_path(std::move(path)), m_derive(derive) {}
bool IsRange() const override { return m_derive != DeriveType::NO; }
size_t GetSize() const override { return 33; }
bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key_out, KeyOriginInfo& final_info_out, const DescriptorCache* read_cache = nullptr, DescriptorCache* write_cache = nullptr) const override
bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key_out, KeyOriginInfo& final_info_out, const DescriptorCache* read_cache = nullptr, DescriptorCache* write_cache = nullptr) override
{
// Info of parent of the to be derived pubkey
KeyOriginInfo parent_info;
@ -323,6 +326,9 @@ public:
final_extkey = parent_extkey;
if (m_derive == DeriveType::UNHARDENED) der = parent_extkey.Derive(final_extkey, pos);
}
} else if (m_cached_xpub.pubkey.IsValid() && m_derive != DeriveType::HARDENED) {
parent_extkey = final_extkey = m_cached_xpub;
if (m_derive == DeriveType::UNHARDENED) der = parent_extkey.Derive(final_extkey, pos);
} else if (IsHardened()) {
CExtKey xprv;
if (!GetDerivedExtKey(arg, xprv)) return false;
@ -344,6 +350,11 @@ public:
final_info_out = final_info_out_tmp;
key_out = final_extkey.pubkey;
// We rely on the consumer to check that m_derive isn't HARDENED as above
// But we can't have already cached something in case we read something from the cache
// and parent_extkey isn't actually the parent.
if (!m_cached_xpub.pubkey.IsValid()) m_cached_xpub = parent_extkey;
if (write_cache) {
// Only cache parent if there is any unhardened derivation
if (m_derive != DeriveType::HARDENED) {

Write Preview
Loading…
Cancel
Save