Merge pull request #5373 from ZcashFoundation/lib-zcash-script-sigops

Add legacy sigops counts to the zcash_script library API

src/Makefile.am

@@ -393,6 +393,7 @@ libbitcoin_common_a_SOURCES = \
   netbase.cpp \
   primitives/block.cpp \
   primitives/transaction.cpp \
+  primitives/tx_version_info.cpp \
   proof_verifier.cpp \
   protocol.cpp \
   pubkey.cpp \
@@ -558,6 +559,7 @@ libzcash_script_la_SOURCES = \
   crypto/sha512.cpp \
   hash.cpp \
   primitives/transaction.cpp \
+  primitives/tx_version_info.cpp \
   pubkey.cpp \
   script/zcash_script.cpp \
   script/interpreter.cpp \

src/primitives/transaction.cpp

@@ -425,45 +425,3 @@ std::string CTransaction::ToString() const
         str += "    " + vout[i].ToString() + "\n";
     return str;
 }
-
-/**
- * Returns the most recent supported transaction version and version group id,
- * as of the specified activation height and active features.
- */
-TxVersionInfo CurrentTxVersionInfo(
-    const Consensus::Params& consensus,
-    int nHeight,
-    bool requireSprout)
-{
-    if (consensus.NetworkUpgradeActive(nHeight, Consensus::UPGRADE_ZFUTURE)) {
-        return {
-            .fOverwintered =   true,
-            .nVersionGroupId = ZFUTURE_VERSION_GROUP_ID,
-            .nVersion =        ZFUTURE_TX_VERSION
-        };
-    } else if (consensus.NetworkUpgradeActive(nHeight, Consensus::UPGRADE_NU5) && !requireSprout) {
-        return {
-            .fOverwintered =   true,
-            .nVersionGroupId = ZIP225_VERSION_GROUP_ID,
-            .nVersion =        ZIP225_TX_VERSION
-        };
-    } else if (consensus.NetworkUpgradeActive(nHeight, Consensus::UPGRADE_SAPLING)) {
-        return {
-            .fOverwintered =   true,
-            .nVersionGroupId = SAPLING_VERSION_GROUP_ID,
-            .nVersion =        SAPLING_TX_VERSION
-        };
-    } else if (consensus.NetworkUpgradeActive(nHeight, Consensus::UPGRADE_OVERWINTER)) {
-        return {
-            .fOverwintered =   true,
-            .nVersionGroupId = OVERWINTER_VERSION_GROUP_ID,
-            .nVersion =        OVERWINTER_TX_VERSION
-        };
-    } else {
-        return {
-            .fOverwintered =   false,
-            .nVersionGroupId = 0,
-            .nVersion =        CTransaction::SPROUT_MIN_CURRENT_VERSION
-        };
-    }
-}

src/primitives/tx_version_info.cpp

@@ -0,0 +1,47 @@
+// Copyright (c) 2021 The Zcash developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or https://www.opensource.org/licenses/mit-license.php .
+
+#include "primitives/transaction.h"
+
+/**
+ * Returns the most recent supported transaction version and version group id,
+ * as of the specified activation height and active features.
+ */
+TxVersionInfo CurrentTxVersionInfo(
+    const Consensus::Params& consensus,
+    int nHeight,
+    bool requireSprout)
+{
+    if (consensus.NetworkUpgradeActive(nHeight, Consensus::UPGRADE_ZFUTURE)) {
+        return {
+            .fOverwintered =   true,
+            .nVersionGroupId = ZFUTURE_VERSION_GROUP_ID,
+            .nVersion =        ZFUTURE_TX_VERSION
+        };
+    } else if (consensus.NetworkUpgradeActive(nHeight, Consensus::UPGRADE_NU5) && !requireSprout) {
+        return {
+            .fOverwintered =   true,
+            .nVersionGroupId = ZIP225_VERSION_GROUP_ID,
+            .nVersion =        ZIP225_TX_VERSION
+        };
+    } else if (consensus.NetworkUpgradeActive(nHeight, Consensus::UPGRADE_SAPLING)) {
+        return {
+            .fOverwintered =   true,
+            .nVersionGroupId = SAPLING_VERSION_GROUP_ID,
+            .nVersion =        SAPLING_TX_VERSION
+        };
+    } else if (consensus.NetworkUpgradeActive(nHeight, Consensus::UPGRADE_OVERWINTER)) {
+        return {
+            .fOverwintered =   true,
+            .nVersionGroupId = OVERWINTER_VERSION_GROUP_ID,
+            .nVersion =        OVERWINTER_TX_VERSION
+        };
+    } else {
+        return {
+            .fOverwintered =   false,
+            .nVersionGroupId = 0,
+            .nVersion =        CTransaction::SPROUT_MIN_CURRENT_VERSION
+        };
+    }
+}

src/rust/src/incremental_sinsemilla_tree_ffi.rs

@@ -6,13 +6,13 @@ use std::mem::size_of_val;
 use std::ptr;
 
 use orchard::{bundle::Authorized, tree::MerkleHashOrchard};
-
+use tracing::error;
 use zcash_primitives::{
     merkle_tree::incremental::{read_frontier_v1, read_tree, write_frontier_v1, write_tree},
     transaction::components::Amount,
 };
 
-use crate::orchard_ffi::{error, CppStreamReader, CppStreamWriter, ReadCb, StreamObj, WriteCb};
+use crate::streams_ffi::{CppStreamReader, CppStreamWriter, ReadCb, StreamObj, WriteCb};
 
 pub const MERKLE_DEPTH: u8 = 32;
 pub const MAX_CHECKPOINTS: usize = 100;

src/rust/src/orchard_ffi.rs

@@ -19,8 +19,6 @@ use zcash_primitives::transaction::{
 
 use crate::streams_ffi::{CppStreamReader, CppStreamWriter, ReadCb, StreamObj, WriteCb};
 
-mod incremental_sinsemilla_tree_ffi;
-
 #[no_mangle]
 pub extern "C" fn orchard_bundle_clone(
     bundle: *const Bundle<Authorized, Amount>,

src/rust/src/rustzcash.rs

@@ -70,6 +70,7 @@ mod tracing_ffi;
 
 mod address_ffi;
 mod history_ffi;
+mod incremental_sinsemilla_tree_ffi;
 mod orchard_ffi;
 mod transaction_ffi;
 mod zip339_ffi;

src/script/zcash_script.cpp

@@ -69,6 +69,22 @@ struct ECCryptoClosure
 };
 
 ECCryptoClosure instance_of_eccryptoclosure;
+
+// Copy of GetLegacySigOpCount from main.cpp commit c4b2ef7c4.
+// Replace with the copy from src/consensus/tx_verify.{cpp,h} after backporting that refactor.
+unsigned int GetLegacySigOpCount(const CTransaction& tx)
+{
+    unsigned int nSigOps = 0;
+    for (const CTxIn& txin : tx.vin)
+    {
+        nSigOps += txin.scriptSig.GetSigOpCount(false);
+    }
+    for (const CTxOut& txout : tx.vout)
+    {
+        nSigOps += txout.scriptPubKey.GetSigOpCount(false);
+    }
+    return nSigOps;
+}
 }
 
 struct PrecomputedTransaction {
@@ -92,7 +108,7 @@ void* zcash_script_new_precomputed_tx(
             return nullptr;
         }
 
-        // Regardless of the verification result, the tx did not error.
+        // Deserializing the tx did not error.
         set_error(err, zcash_script_ERR_OK);
         auto preTx = new PrecomputedTransaction(tx);
         return preTx;
@@ -166,6 +182,42 @@ int zcash_script_verify(
     }
 }
 
+unsigned int zcash_script_legacy_sigop_count_precomputed(
+    const void* pre_preTx,
+    zcash_script_error* err)
+{
+    const PrecomputedTransaction* preTx = static_cast<const PrecomputedTransaction*>(pre_preTx);
+
+    // The current implementation of this method never errors.
+    set_error(err, zcash_script_ERR_OK);
+
+    return GetLegacySigOpCount(preTx->tx);
+}
+
+unsigned int zcash_script_legacy_sigop_count(
+    const unsigned char *txTo,
+    unsigned int txToLen,
+    zcash_script_error* err)
+{
+    try {
+        TxInputStream stream(SER_NETWORK, PROTOCOL_VERSION, txTo, txToLen);
+        CTransaction tx;
+        stream >> tx;
+        if (GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION) != txToLen) {
+            set_error(err, zcash_script_ERR_TX_SIZE_MISMATCH);
+            return UINT_MAX;
+        }
+
+        // Deserializing the tx did not error.
+        set_error(err, zcash_script_ERR_OK);
+
+        return GetLegacySigOpCount(tx);
+    } catch (const std::exception&) {
+        set_error(err, zcash_script_ERR_TX_DESERIALIZE); // Error deserializing
+        return UINT_MAX;
+    }
+}
+
 unsigned int zcash_script_version()
 {
     // Just use the API version for now

src/script/zcash_script.h

@@ -33,7 +33,7 @@
 extern "C" {
 #endif
 
-#define ZCASH_SCRIPT_API_VER 1
+#define ZCASH_SCRIPT_API_VER 2
 
 typedef enum zcash_script_error_t
 {
@@ -99,6 +99,28 @@ EXPORT_SYMBOL int zcash_script_verify(
     uint32_t consensusBranchId,
     zcash_script_error* err);
 
+/// Returns the number of transparent signature operations in the
+/// transparent inputs and outputs of the precomputed transaction
+/// pointed to by preTx.
+///
+/// Returns UINT_MAX on error, so that invalid transactions don't pass the Zcash consensus rules.
+/// If not NULL, err will contain an error/success code for the operation.
+EXPORT_SYMBOL unsigned int zcash_script_legacy_sigop_count_precomputed(
+    const void* preTx,
+    zcash_script_error* err);
+
+/// Returns the number of transparent signature operations in the
+/// transparent inputs and outputs of the serialized transaction
+/// pointed to by txTo.
+///
+/// Returns UINT_MAX on error.
+/// If not NULL, err will contain an error/success code for the operation.
+EXPORT_SYMBOL unsigned int zcash_script_legacy_sigop_count(
+    const unsigned char *txTo,
+    unsigned int txToLen,
+    zcash_script_error* err);
+
+/// Returns the current version of the zcash_script library.
 EXPORT_SYMBOL unsigned int zcash_script_version();
 
 #ifdef __cplusplus