Merge #13697: Support output descriptors in scantxoutset

f6b7fc349ccf9cfbeb7e91e19c20e2a2fcc9026f Support h instead of ' in hardened descriptor paths (Pieter Wuille)
fddea672eb8f63012f2e9ce04fa477e5d4140750 Add experimental warning to scantxoutset (Jonas Schnelli)
6495849bfd362d6a2f128bac5982fa9e3e2e3396 [QA] Extend tests to more combinations (Pieter Wuille)
1af237faefc316bd708e25d6901ee6f17b706e57 [QA] Add xpub range tests in scantxoutset tests (Jonas Schnelli)
151600bb4972f7bab4ed4a03d1f67c38e081fefe Swap in descriptors support into scantxoutset (Pieter Wuille)
0652c3284fe12941b28624dbbf5e0862c5d0dbc3 Descriptor tests (Pieter Wuille)
fe8a7dcd78cfeedc9a7c705e91384f793822912b Output descriptors module (Pieter Wuille)
e54d76044b3a2c625e53f2116c5f6a7c40105d5d Add simple FlatSigningProvider (Pieter Wuille)
29943a904a11607787d28b1f4288f500bd076dde Add more methods to Span class (Pieter Wuille)

Pull request description:

  As promised, here is an implementation of my output descriptor concept (https://gist.github.com/sipa/e3d23d498c430bb601c5bca83523fa82) and integration within the `scantxoutset` RPC that was just added through #12196.

  It changes the RPC to use descriptors for everything; I hope the interface is simple enough to encompass all use cases. It includes support for P2PK, P2PKH, P2WPKH, P2SH, P2WSH, multisig, xpubs, xprvs, and chains of keys - combined in every possible way.

Tree-SHA512: 63b54a96e7a72f5b04a8d645b8517d43ecd6a65a41f9f4e593931ce725a8845ab0baa1e9db6a7243190d8ac841f6e7e2f520d98c539312d78f7fd687d2c7b88f

1 files changed, 28 insertions, 2 deletions

diff --git a/src/script/sign.cpp b/src/script/sign.cpp
index d10b1c4fd7..fa09adbaf8 100644
--- a/src/script/sign.cpp
+++ b/src/script/sign.cpp
@@ -11,7 +11,6 @@
 #include <script/standard.h>
 #include <uint256.h>
 
-
 typedef std::vector<unsigned char> valtype;
 
 MutableTransactionSignatureCreator::MutableTransactionSignatureCreator(const CMutableTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, int nHashTypeIn) : txTo(txToIn), nIn(nInIn), nHashType(nHashTypeIn), amount(amountIn), checker(txTo, nIn, amountIn) {}
@@ -437,6 +436,18 @@ public:
         return true;
     }
 };
+
+template<typename M, typename K, typename V>
+bool LookupHelper(const M& map, const K& key, V& value)
+{
+    auto it = map.find(key);
+    if (it != map.end()) {
+        value = it->second;
+        return true;
+    }
+    return false;
+}
+
 }
 
 const BaseSignatureCreator& DUMMY_SIGNATURE_CREATOR = DummySignatureCreator();
@@ -460,7 +471,6 @@ bool IsSolvable(const SigningProvider& provider, const CScript& script)
     return false;
 }
 
-
 bool PartiallySignedTransaction::IsNull() const
 {
     return !tx && inputs.empty() && outputs.empty() && unknown.empty();
@@ -618,3 +628,19 @@ bool PublicOnlySigningProvider::GetPubKey(const CKeyID &address, CPubKey& pubkey
 {
     return m_provider->GetPubKey(address, pubkey);
 }
+
+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::GetKey(const CKeyID& keyid, CKey& key) const { return LookupHelper(keys, keyid, key); }
+
+FlatSigningProvider Merge(const FlatSigningProvider& a, const FlatSigningProvider& b)
+{
+    FlatSigningProvider ret;
+    ret.scripts = a.scripts;
+    ret.scripts.insert(b.scripts.begin(), b.scripts.end());
+    ret.pubkeys = a.pubkeys;
+    ret.pubkeys.insert(b.pubkeys.begin(), b.pubkeys.end());
+    ret.keys = a.keys;
+    ret.keys.insert(b.keys.begin(), b.keys.end());
+    return ret;
+}