1 files changed, 121 insertions, 0 deletions
diff --git a/src/addresstype.h b/src/addresstype.h
new file mode 100644
index 0000000000..6b651e9014
--- /dev/null
+++ b/src/addresstype.h
@@ -0,0 +1,121 @@
+// Copyright (c) 2023 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or https://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_ADDRESSTYPE_H
+#define BITCOIN_ADDRESSTYPE_H
+
+#include <pubkey.h>
+#include <script/script.h>
+#include <uint256.h>
+#include <util/hash_type.h>
+
+#include <variant>
+#include <algorithm>
+
+class CNoDestination {
+public:
+    friend bool operator==(const CNoDestination &a, const CNoDestination &b) { return true; }
+    friend bool operator<(const CNoDestination &a, const CNoDestination &b) { return true; }
+};
+
+struct PKHash : public BaseHash<uint160>
+{
+    PKHash() : BaseHash() {}
+    explicit PKHash(const uint160& hash) : BaseHash(hash) {}
+    explicit PKHash(const CPubKey& pubkey);
+    explicit PKHash(const CKeyID& pubkey_id);
+};
+CKeyID ToKeyID(const PKHash& key_hash);
+
+struct WitnessV0KeyHash;
+
+struct ScriptHash : public BaseHash<uint160>
+{
+    ScriptHash() : BaseHash() {}
+    // These don't do what you'd expect.
+    // Use ScriptHash(GetScriptForDestination(...)) instead.
+    explicit ScriptHash(const WitnessV0KeyHash& hash) = delete;
+    explicit ScriptHash(const PKHash& hash) = delete;
+
+    explicit ScriptHash(const uint160& hash) : BaseHash(hash) {}
+    explicit ScriptHash(const CScript& script);
+    explicit ScriptHash(const CScriptID& script);
+};
+CScriptID ToScriptID(const ScriptHash& script_hash);
+
+struct WitnessV0ScriptHash : public BaseHash<uint256>
+{
+    WitnessV0ScriptHash() : BaseHash() {}
+    explicit WitnessV0ScriptHash(const uint256& hash) : BaseHash(hash) {}
+    explicit WitnessV0ScriptHash(const CScript& script);
+};
+
+struct WitnessV0KeyHash : public BaseHash<uint160>
+{
+    WitnessV0KeyHash() : BaseHash() {}
+    explicit WitnessV0KeyHash(const uint160& hash) : BaseHash(hash) {}
+    explicit WitnessV0KeyHash(const CPubKey& pubkey);
+    explicit WitnessV0KeyHash(const PKHash& pubkey_hash);
+};
+CKeyID ToKeyID(const WitnessV0KeyHash& key_hash);
+
+struct WitnessV1Taproot : public XOnlyPubKey
+{
+    WitnessV1Taproot() : XOnlyPubKey() {}
+    explicit WitnessV1Taproot(const XOnlyPubKey& xpk) : XOnlyPubKey(xpk) {}
+};
+
+//! CTxDestination subtype to encode any future Witness version
+struct WitnessUnknown
+{
+    unsigned int version;
+    unsigned int length;
+    unsigned char program[40];
+
+    friend bool operator==(const WitnessUnknown& w1, const WitnessUnknown& w2) {
+        if (w1.version != w2.version) return false;
+        if (w1.length != w2.length) return false;
+        return std::equal(w1.program, w1.program + w1.length, w2.program);
+    }
+
+    friend bool operator<(const WitnessUnknown& w1, const WitnessUnknown& w2) {
+        if (w1.version < w2.version) return true;
+        if (w1.version > w2.version) return false;
+        if (w1.length < w2.length) return true;
+        if (w1.length > w2.length) return false;
+        return std::lexicographical_compare(w1.program, w1.program + w1.length, w2.program, w2.program + w2.length);
+    }
+};
+
+/**
+ * A txout script template with a specific destination. It is either:
+ *  * CNoDestination: no destination set
+ *  * PKHash: TxoutType::PUBKEYHASH destination (P2PKH)
+ *  * ScriptHash: TxoutType::SCRIPTHASH destination (P2SH)
+ *  * WitnessV0ScriptHash: TxoutType::WITNESS_V0_SCRIPTHASH destination (P2WSH)
+ *  * WitnessV0KeyHash: TxoutType::WITNESS_V0_KEYHASH destination (P2WPKH)
+ *  * WitnessV1Taproot: TxoutType::WITNESS_V1_TAPROOT destination (P2TR)
+ *  * WitnessUnknown: TxoutType::WITNESS_UNKNOWN destination (P2W???)
+ *  A CTxDestination is the internal data type encoded in a bitcoin address
+ */
+using CTxDestination = std::variant<CNoDestination, PKHash, ScriptHash, WitnessV0ScriptHash, WitnessV0KeyHash, WitnessV1Taproot, WitnessUnknown>;
+
+/** Check whether a CTxDestination is a CNoDestination. */
+bool IsValidDestination(const CTxDestination& dest);
+
+/**
+ * Parse a standard scriptPubKey for the destination address. Assigns result to
+ * the addressRet parameter and returns true if successful. Currently only works for P2PK,
+ * P2PKH, P2SH, P2WPKH, and P2WSH scripts.
+ */
+bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet);
+
+/**
+ * Generate a Bitcoin scriptPubKey for the given CTxDestination. Returns a P2PKH
+ * script for a CKeyID destination, a P2SH script for a CScriptID, and an empty
+ * script for CNoDestination.
+ */
+CScript GetScriptForDestination(const CTxDestination& dest);
+
+#endif // BITCOIN_ADDRESSTYPE_H