Wallet/RPC: Allow specifying min & max chain depth for inputs used by fund calls

Enables users to craft BIP-125 replacements with changes to the output
list, ensuring that if additional funds are needed they will be added.

1 files changed, 24 insertions, 0 deletions

diff --git a/src/wallet/rpc/spend.cpp b/src/wallet/rpc/spend.cpp
index be1ad37592..280d6a8061 100644
--- a/src/wallet/rpc/spend.cpp
+++ b/src/wallet/rpc/spend.cpp
@@ -528,6 +528,8 @@ void FundTransaction(CWallet& wallet, CMutableTransaction& tx, CAmount& fee_out,
                 {"replaceable", UniValueType(UniValue::VBOOL)},
                 {"conf_target", UniValueType(UniValue::VNUM)},
                 {"estimate_mode", UniValueType(UniValue::VSTR)},
+                {"minconf", UniValueType(UniValue::VNUM)},
+                {"maxconf", UniValueType(UniValue::VNUM)},
                 {"input_weights", UniValueType(UniValue::VARR)},
             },
             true, true);
@@ -593,6 +595,22 @@ void FundTransaction(CWallet& wallet, CMutableTransaction& tx, CAmount& fee_out,
         if (options.exists("replaceable")) {
             coinControl.m_signal_bip125_rbf = options["replaceable"].get_bool();
         }
+
+        if (options.exists("minconf")) {
+            coinControl.m_min_depth = options["minconf"].getInt<int>();
+
+            if (coinControl.m_min_depth < 0) {
+                throw JSONRPCError(RPC_INVALID_PARAMETER, "Negative minconf");
+            }
+        }
+
+        if (options.exists("maxconf")) {
+            coinControl.m_max_depth = options["maxconf"].getInt<int>();
+
+            if (coinControl.m_max_depth < coinControl.m_min_depth) {
+                throw JSONRPCError(RPC_INVALID_PARAMETER, strprintf("maxconf can't be lower than minconf: %d < %d", coinControl.m_max_depth, coinControl.m_min_depth));
+            }
+        }
         SetFeeEstimateMode(wallet, coinControl, options["conf_target"], options["estimate_mode"], options["fee_rate"], override_min_fee);
       }
     } else {
@@ -744,6 +762,8 @@ RPCHelpMan fundrawtransaction()
                             {"include_unsafe", RPCArg::Type::BOOL, RPCArg::Default{false}, "Include inputs that are not safe to spend (unconfirmed transactions from outside keys and unconfirmed replacement transactions).\n"
                                                           "Warning: the resulting transaction may become invalid if one of the unsafe inputs disappears.\n"
                                                           "If that happens, you will need to fund the transaction with different inputs and republish it."},
+                            {"minconf", RPCArg::Type::NUM, RPCArg::Default{0}, "If add_inputs is specified, require inputs with at least this many confirmations."},
+                            {"maxconf", RPCArg::Type::NUM, RPCArg::Optional::OMITTED, "If add_inputs is specified, require inputs with at most this many confirmations."},
                             {"changeAddress", RPCArg::Type::STR, RPCArg::DefaultHint{"automatic"}, "The bitcoin address to receive the change"},
                             {"changePosition", RPCArg::Type::NUM, RPCArg::DefaultHint{"random"}, "The index of the change output"},
                             {"change_type", RPCArg::Type::STR, RPCArg::DefaultHint{"set by -changetype"}, "The output type to use. Only valid if changeAddress is not specified. Options are \"legacy\", \"p2sh-segwit\", \"bech32\", and \"bech32m\"."},
@@ -1147,6 +1167,8 @@ RPCHelpMan send()
                     {"include_unsafe", RPCArg::Type::BOOL, RPCArg::Default{false}, "Include inputs that are not safe to spend (unconfirmed transactions from outside keys and unconfirmed replacement transactions).\n"
                                                           "Warning: the resulting transaction may become invalid if one of the unsafe inputs disappears.\n"
                                                           "If that happens, you will need to fund the transaction with different inputs and republish it."},
+                    {"minconf", RPCArg::Type::NUM, RPCArg::Default{0}, "If add_inputs is specified, require inputs with at least this many confirmations."},
+                    {"maxconf", RPCArg::Type::NUM, RPCArg::Optional::OMITTED, "If add_inputs is specified, require inputs with at most this many confirmations."},
                     {"add_to_wallet", RPCArg::Type::BOOL, RPCArg::Default{true}, "When false, returns a serialized transaction which will not be added to the wallet or broadcast"},
                     {"change_address", RPCArg::Type::STR, RPCArg::DefaultHint{"automatic"}, "The bitcoin address to receive the change"},
                     {"change_position", RPCArg::Type::NUM, RPCArg::DefaultHint{"random"}, "The index of the change output"},
@@ -1603,6 +1625,8 @@ RPCHelpMan walletcreatefundedpsbt()
                             {"include_unsafe", RPCArg::Type::BOOL, RPCArg::Default{false}, "Include inputs that are not safe to spend (unconfirmed transactions from outside keys and unconfirmed replacement transactions).\n"
                                                           "Warning: the resulting transaction may become invalid if one of the unsafe inputs disappears.\n"
                                                           "If that happens, you will need to fund the transaction with different inputs and republish it."},
+                            {"minconf", RPCArg::Type::NUM, RPCArg::Default{0}, "If add_inputs is specified, require inputs with at least this many confirmations."},
+                            {"maxconf", RPCArg::Type::NUM, RPCArg::Optional::OMITTED, "If add_inputs is specified, require inputs with at most this many confirmations."},
                             {"changeAddress", RPCArg::Type::STR, RPCArg::DefaultHint{"automatic"}, "The bitcoin address to receive the change"},
                             {"changePosition", RPCArg::Type::NUM, RPCArg::DefaultHint{"random"}, "The index of the change output"},
                             {"change_type", RPCArg::Type::STR, RPCArg::DefaultHint{"set by -changetype"}, "The output type to use. Only valid if changeAddress is not specified. Options are \"legacy\", \"p2sh-segwit\", \"bech32\", and \"bech32m\"."},