Add key origin support to descriptors

This commit is contained in:
Pieter Wuille 2018-07-18 12:24:36 -07:00
parent 5c25409d68
commit 2c6281f180
3 changed files with 100 additions and 27 deletions

View file

@ -41,7 +41,7 @@ struct PubkeyProvider
virtual ~PubkeyProvider() = default;
/** Derive a public key. */
virtual bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& out) const = 0;
virtual bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info) const = 0;
/** Whether this represent multiple public keys at different positions. */
virtual bool IsRange() const = 0;
@ -56,6 +56,37 @@ struct PubkeyProvider
virtual bool ToPrivateString(const SigningProvider& arg, std::string& out) const = 0;
};
class OriginPubkeyProvider final : public PubkeyProvider
{
KeyOriginInfo m_origin;
std::unique_ptr<PubkeyProvider> m_provider;
std::string OriginString() const
{
return HexStr(std::begin(m_origin.fingerprint), std::end(m_origin.fingerprint)) + FormatKeyPath(m_origin.path);
}
public:
OriginPubkeyProvider(KeyOriginInfo info, std::unique_ptr<PubkeyProvider> provider) : m_origin(std::move(info)), m_provider(std::move(provider)) {}
bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info) const override
{
if (!m_provider->GetPubKey(pos, arg, key, info)) return false;
std::copy(std::begin(m_origin.fingerprint), std::end(m_origin.fingerprint), info.fingerprint);
info.path.insert(info.path.begin(), m_origin.path.begin(), m_origin.path.end());
return true;
}
bool IsRange() const override { return m_provider->IsRange(); }
size_t GetSize() const override { return m_provider->GetSize(); }
std::string ToString() const override { return "[" + OriginString() + "]" + m_provider->ToString(); }
bool ToPrivateString(const SigningProvider& arg, std::string& ret) const override
{
std::string sub;
if (!m_provider->ToPrivateString(arg, sub)) return false;
ret = "[" + OriginString() + "]" + std::move(sub);
return true;
}
};
/** An object representing a parsed constant public key in a descriptor. */
class ConstPubkeyProvider final : public PubkeyProvider
{
@ -63,9 +94,12 @@ class ConstPubkeyProvider final : public PubkeyProvider
public:
ConstPubkeyProvider(const CPubKey& pubkey) : m_pubkey(pubkey) {}
bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& out) const override
bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info) const override
{
out = m_pubkey;
key = m_pubkey;
info.path.clear();
CKeyID keyid = m_pubkey.GetID();
std::copy(keyid.begin(), keyid.begin() + sizeof(info.fingerprint), info.fingerprint);
return true;
}
bool IsRange() const override { return false; }
@ -98,7 +132,7 @@ class BIP32PubkeyProvider final : public PubkeyProvider
CKey key;
if (!arg.GetKey(m_extkey.pubkey.GetID(), key)) return false;
ret.nDepth = m_extkey.nDepth;
std::copy(m_extkey.vchFingerprint, m_extkey.vchFingerprint + 4, ret.vchFingerprint);
std::copy(m_extkey.vchFingerprint, m_extkey.vchFingerprint + sizeof(ret.vchFingerprint), ret.vchFingerprint);
ret.nChild = m_extkey.nChild;
ret.chaincode = m_extkey.chaincode;
ret.key = key;
@ -118,27 +152,32 @@ public:
BIP32PubkeyProvider(const CExtPubKey& extkey, KeyPath path, DeriveType derive) : m_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& out) const override
bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info) const override
{
if (IsHardened()) {
CExtKey key;
if (!GetExtKey(arg, key)) return false;
CExtKey extkey;
if (!GetExtKey(arg, extkey)) return false;
for (auto entry : m_path) {
key.Derive(key, entry);
extkey.Derive(extkey, entry);
}
if (m_derive == DeriveType::UNHARDENED) key.Derive(key, pos);
if (m_derive == DeriveType::HARDENED) key.Derive(key, pos | 0x80000000UL);
out = key.Neuter().pubkey;
if (m_derive == DeriveType::UNHARDENED) extkey.Derive(extkey, pos);
if (m_derive == DeriveType::HARDENED) extkey.Derive(extkey, pos | 0x80000000UL);
key = extkey.Neuter().pubkey;
} else {
// TODO: optimize by caching
CExtPubKey key = m_extkey;
CExtPubKey extkey = m_extkey;
for (auto entry : m_path) {
key.Derive(key, entry);
extkey.Derive(extkey, entry);
}
if (m_derive == DeriveType::UNHARDENED) key.Derive(key, pos);
if (m_derive == DeriveType::UNHARDENED) extkey.Derive(extkey, pos);
assert(m_derive != DeriveType::HARDENED);
out = key.pubkey;
key = extkey.pubkey;
}
CKeyID keyid = m_extkey.pubkey.GetID();
std::copy(keyid.begin(), keyid.begin() + sizeof(info.fingerprint), info.fingerprint);
info.path = m_path;
if (m_derive == DeriveType::UNHARDENED) info.path.push_back((uint32_t)pos);
if (m_derive == DeriveType::HARDENED) info.path.push_back(((uint32_t)pos) | 0x80000000L);
return true;
}
std::string ToString() const override
@ -221,9 +260,11 @@ public:
bool Expand(int pos, const SigningProvider& arg, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const override
{
CPubKey key;
if (!m_provider->GetPubKey(pos, arg, key)) return false;
KeyOriginInfo info;
if (!m_provider->GetPubKey(pos, arg, key, info)) return false;
output_scripts = std::vector<CScript>{m_script_fn(key)};
out.pubkeys.emplace(key.GetID(), std::move(key));
out.origins.emplace(key.GetID(), std::move(info));
out.pubkeys.emplace(key.GetID(), key);
return true;
}
};
@ -272,15 +313,19 @@ public:
bool Expand(int pos, const SigningProvider& arg, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const override
{
std::vector<CPubKey> pubkeys;
pubkeys.reserve(m_providers.size());
std::vector<std::pair<CPubKey, KeyOriginInfo>> entries;
entries.reserve(m_providers.size());
// Construct temporary data in `entries`, to avoid producing output in case of failure.
for (const auto& p : m_providers) {
CPubKey key;
if (!p->GetPubKey(pos, arg, key)) return false;
pubkeys.push_back(key);
entries.emplace_back();
if (!p->GetPubKey(pos, arg, entries.back().first, entries.back().second)) return false;
}
for (const CPubKey& key : pubkeys) {
out.pubkeys.emplace(key.GetID(), std::move(key));
std::vector<CPubKey> pubkeys;
pubkeys.reserve(entries.size());
for (auto& entry : entries) {
pubkeys.push_back(entry.first);
out.origins.emplace(entry.first.GetID(), std::move(entry.second));
out.pubkeys.emplace(entry.first.GetID(), entry.first);
}
output_scripts = std::vector<CScript>{GetScriptForMultisig(m_threshold, pubkeys)};
return true;
@ -343,13 +388,15 @@ public:
bool Expand(int pos, const SigningProvider& arg, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const override
{
CPubKey key;
if (!m_provider->GetPubKey(pos, arg, key)) return false;
KeyOriginInfo info;
if (!m_provider->GetPubKey(pos, arg, key, info)) return false;
CKeyID keyid = key.GetID();
{
CScript p2pk = GetScriptForRawPubKey(key);
CScript p2pkh = GetScriptForDestination(keyid);
output_scripts = std::vector<CScript>{std::move(p2pk), std::move(p2pkh)};
out.pubkeys.emplace(keyid, key);
out.origins.emplace(keyid, std::move(info));
}
if (key.IsCompressed()) {
CScript p2wpkh = GetScriptForDestination(WitnessV0KeyHash(keyid));
@ -447,7 +494,8 @@ bool ParseKeyPath(const std::vector<Span<const char>>& split, KeyPath& out)
return true;
}
std::unique_ptr<PubkeyProvider> ParsePubkey(const Span<const char>& sp, bool permit_uncompressed, FlatSigningProvider& out)
/** Parse a public key that excludes origin information. */
std::unique_ptr<PubkeyProvider> ParsePubkeyInner(const Span<const char>& sp, bool permit_uncompressed, FlatSigningProvider& out)
{
auto split = Split(sp, '/');
std::string str(split[0].begin(), split[0].end());
@ -484,6 +532,28 @@ std::unique_ptr<PubkeyProvider> ParsePubkey(const Span<const char>& sp, bool per
return MakeUnique<BIP32PubkeyProvider>(extpubkey, std::move(path), type);
}
/** Parse a public key including origin information (if enabled). */
std::unique_ptr<PubkeyProvider> ParsePubkey(const Span<const char>& sp, bool permit_uncompressed, FlatSigningProvider& out)
{
auto origin_split = Split(sp, ']');
if (origin_split.size() > 2) return nullptr;
if (origin_split.size() == 1) return ParsePubkeyInner(origin_split[0], permit_uncompressed, out);
if (origin_split[0].size() < 1 || origin_split[0][0] != '[') return nullptr;
auto slash_split = Split(origin_split[0].subspan(1), '/');
if (slash_split[0].size() != 8) return nullptr;
std::string fpr_hex = std::string(slash_split[0].begin(), slash_split[0].end());
if (!IsHex(fpr_hex)) return nullptr;
auto fpr_bytes = ParseHex(fpr_hex);
KeyOriginInfo info;
static_assert(sizeof(info.fingerprint) == 4, "Fingerprint must be 4 bytes");
assert(fpr_bytes.size() == 4);
std::copy(fpr_bytes.begin(), fpr_bytes.end(), info.fingerprint);
if (!ParseKeyPath(slash_split, info.path)) return nullptr;
auto provider = ParsePubkeyInner(origin_split[1], permit_uncompressed, out);
if (!provider) return nullptr;
return MakeUnique<OriginPubkeyProvider>(std::move(info), std::move(provider));
}
/** Parse a script in a particular context. */
std::unique_ptr<Descriptor> ParseScript(Span<const char>& sp, ParseScriptContext ctx, FlatSigningProvider& out)
{

View file

@ -686,6 +686,7 @@ bool HidingSigningProvider::GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& inf
bool FlatSigningProvider::GetCScript(const CScriptID& scriptid, CScript& script) const { return LookupHelper(scripts, scriptid, script); }
bool FlatSigningProvider::GetPubKey(const CKeyID& keyid, CPubKey& pubkey) const { return LookupHelper(pubkeys, keyid, pubkey); }
bool FlatSigningProvider::GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& info) const { return LookupHelper(origins, keyid, info); }
bool FlatSigningProvider::GetKey(const CKeyID& keyid, CKey& key) const { return LookupHelper(keys, keyid, key); }
FlatSigningProvider Merge(const FlatSigningProvider& a, const FlatSigningProvider& b)

View file

@ -34,7 +34,7 @@ public:
virtual bool GetCScript(const CScriptID &scriptid, CScript& script) const { return false; }
virtual bool GetPubKey(const CKeyID &address, CPubKey& pubkey) const { return false; }
virtual bool GetKey(const CKeyID &address, CKey& key) const { return false; }
virtual bool GetKeyOrigin(const CKeyID& id, KeyOriginInfo& info) const { return false; }
virtual bool GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& info) const { return false; }
};
extern const SigningProvider& DUMMY_SIGNING_PROVIDER;
@ -58,10 +58,12 @@ struct FlatSigningProvider final : public SigningProvider
{
std::map<CScriptID, CScript> scripts;
std::map<CKeyID, CPubKey> pubkeys;
std::map<CKeyID, KeyOriginInfo> origins;
std::map<CKeyID, CKey> keys;
bool GetCScript(const CScriptID& scriptid, CScript& script) const override;
bool GetPubKey(const CKeyID& keyid, CPubKey& pubkey) const override;
bool GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& info) const override;
bool GetKey(const CKeyID& keyid, CKey& key) const override;
};