BIP143: Signing logic

1 files changed, 41 insertions, 0 deletions

diff --git a/src/script/standard.cpp b/src/script/standard.cpp
index 67b6af327a..bb178f49fe 100644
--- a/src/script/standard.cpp
+++ b/src/script/standard.cpp
@@ -31,6 +31,8 @@ const char* GetTxnOutputType(txnouttype t)
     case TX_SCRIPTHASH: return "scripthash";
     case TX_MULTISIG: return "multisig";
     case TX_NULL_DATA: return "nulldata";
+    case TX_WITNESS_V0_KEYHASH: return "witness_v0_keyhash";
+    case TX_WITNESS_V0_SCRIPTHASH: return "witness_v0_scripthash";
     }
     return NULL;
 }
@@ -66,6 +68,22 @@ bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, vector<vector<unsi
         return true;
     }
 
+    int witnessversion;
+    std::vector<unsigned char> witnessprogram;
+    if (scriptPubKey.IsWitnessProgram(witnessversion, witnessprogram)) {
+        if (witnessversion == 0 && witnessprogram.size() == 20) {
+            typeRet = TX_WITNESS_V0_KEYHASH;
+            vSolutionsRet.push_back(witnessprogram);
+            return true;
+        }
+        if (witnessversion == 0 && witnessprogram.size() == 32) {
+            typeRet = TX_WITNESS_V0_SCRIPTHASH;
+            vSolutionsRet.push_back(witnessprogram);
+            return true;
+        }
+        return false;
+    }
+
     // Provably prunable, data-carrying output
     //
     // So long as script passes the IsUnspendable() test and all but the first
@@ -282,3 +300,26 @@ CScript GetScriptForMultisig(int nRequired, const std::vector<CPubKey>& keys)
     script << CScript::EncodeOP_N(keys.size()) << OP_CHECKMULTISIG;
     return script;
 }
+
+CScript GetScriptForWitness(const CScript& redeemscript)
+{
+    CScript ret;
+
+    txnouttype typ;
+    std::vector<std::vector<unsigned char> > vSolutions;
+    if (Solver(redeemscript, typ, vSolutions)) {
+        if (typ == TX_PUBKEY) {
+            unsigned char h160[20];
+            CHash160().Write(&vSolutions[0][0], vSolutions[0].size()).Finalize(h160);
+            ret << OP_0 << std::vector<unsigned char>(&h160[0], &h160[20]);
+            return ret;
+        } else if (typ == TX_PUBKEYHASH) {
+           ret << OP_0 << vSolutions[0];
+           return ret;
+        }
+    }
+    uint256 hash;
+    CSHA256().Write(&redeemscript[0], redeemscript.size()).Finalize(hash.begin());
+    ret << OP_0 << ToByteVector(hash);
+    return ret;
+}