build: add libbitcoinconsensus files and hook up the lib build

Credit BlueMatt for libbitcoinsonsensus.h/cpp

.gitignore

@@ -45,6 +45,7 @@ src/qt/test/moc*.cpp
 
 .deps
 .dirstamp
+.libs
 .*.swp
 *.*~*
 *.bak
@@ -66,6 +67,10 @@ src/qt/test/moc*.cpp
 *.json.h
 *.raw.h
 
+#libtool object files
+*.lo
+*.la
+
 # Compilation and Qt preprocessor part
 *.qm
 Makefile

src/Makefile.am

@@ -49,6 +49,8 @@ BITCOIN_INCLUDES += $(BDB_CPPFLAGS)
 noinst_LIBRARIES += libbitcoin_wallet.a
 endif
 
+lib_LTLIBRARIES = libbitcoinconsensus.la
+
 bin_PROGRAMS =
 TESTS =
 
@@ -331,6 +333,35 @@ bitcoin_cli_SOURCES += bitcoin-cli-res.rc
 endif
 bitcoin_cli_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
 
+if BUILD_BITCOIN_LIBS
+include_HEADERS = script/bitcoinconsensus.h
+libbitcoinconsensus_la_SOURCES = \
+  core/transaction.cpp \
+  crypto/sha1.cpp \
+  crypto/sha2.cpp \
+  crypto/ripemd160.cpp \
+  eccryptoverify.cpp \
+  ecwrapper.cpp \
+  hash.cpp \
+  pubkey.cpp \
+  script/script.cpp \
+  script/interpreter.cpp \
+  script/bitcoinconsensus.cpp \
+  uint256.cpp \
+  utilstrencodings.cpp
+
+if GLIBC_BACK_COMPAT
+  libbitcoinconsensus_la_SOURCES += compat/glibc_compat.cpp
+  libbitcoinconsensus_la_SOURCES += compat/glibcxx_compat.cpp
+endif
+
+libbitcoinconsensus_la_LDFLAGS = -no-undefined $(RELDFLAGS)
+libbitcoinconsensus_la_LIBADD = $(CRYPTO_LIBS)
+libbitcoinconsensus_la_CPPFLAGS = $(CRYPTO_CFLAGS) -I$(builddir)/obj -DBUILD_BITCOIN_INTERNAL
+if USE_LIBSECP256K1
+libbitcoinconsensus_la_LIBADD += secp256k1/libsecp256k1.la
+endif
+
 CLEANFILES = leveldb/libleveldb.a leveldb/libmemenv.a *.gcda *.gcno
 
 DISTCLEANFILES = obj/build.h

src/Makefile.test.include

@@ -86,7 +86,7 @@ test_test_bitcoin_LDADD += $(LIBBITCOIN_WALLET)
 endif
 
 test_test_bitcoin_LDADD += $(BDB_LIBS) $(SSL_LIBS) $(CRYPTO_LIBS) $(MINIUPNPC_LIBS)
-test_test_bitcoin_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
+test_test_bitcoin_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS) -static-libtool-libs
 
 nodist_test_test_bitcoin_SOURCES = $(GENERATED_TEST_FILES)
 

src/script/bitcoinconsensus.cpp

@@ -0,0 +1,91 @@
+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2014 The Bitcoin developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include "bitcoinconsensus.h"
+
+#include "core/transaction.h"
+#include "script/interpreter.h"
+#include "version.h"
+
+namespace {
+
+/** A class that deserializes a single CTransaction one time. */
+class TxInputStream
+{
+public:
+    TxInputStream(int nTypeIn, int nVersionIn, const unsigned char *txTo, size_t txToLen) :
+    m_type(nTypeIn),
+    m_version(nVersionIn),
+    m_data(txTo),
+    m_remaining(txToLen)
+    {}
+
+    TxInputStream& read(char* pch, size_t nSize)
+    {
+        if (nSize > m_remaining)
+            throw std::ios_base::failure(std::string(__func__) + ": end of data");
+
+        if (pch == NULL)
+            throw std::ios_base::failure(std::string(__func__) + ": bad destination buffer");
+
+        if (m_data == NULL)
+            throw std::ios_base::failure(std::string(__func__) + ": bad source buffer");
+
+        memcpy(pch, m_data, nSize);
+        m_remaining -= nSize;
+        m_data += nSize;
+        return *this;
+    }
+
+    template<typename T>
+    TxInputStream& operator>>(T& obj)
+    {
+        ::Unserialize(*this, obj, m_type, m_version);
+        return *this;
+    }
+
+private:
+    const int m_type;
+    const int m_version;
+    const unsigned char* m_data;
+    size_t m_remaining;
+};
+
+inline int set_error(bitcoinconsensus_error* ret, bitcoinconsensus_error serror)
+{
+    if (ret)
+        *ret = serror;
+    return 0;
+}
+
+} // anon namespace
+
+int bitcoinconsensus_verify_script(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen,
+                                    const unsigned char *txTo        , unsigned int txToLen,
+                                    unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err)
+{
+    try {
+        TxInputStream stream(SER_NETWORK, PROTOCOL_VERSION, txTo, txToLen);
+        CTransaction tx;
+        stream >> tx;
+        if (nIn >= tx.vin.size())
+            return set_error(err, bitcoinconsensus_ERR_TX_INDEX);
+        if (tx.GetSerializeSize(SER_NETWORK, PROTOCOL_VERSION) != txToLen)
+            return set_error(err, bitcoinconsensus_ERR_TX_SIZE_MISMATCH);
+
+         // Regardless of the verification result, the tx did not error.
+         set_error(err, bitcoinconsensus_ERR_OK);
+
+        return VerifyScript(tx.vin[nIn].scriptSig, CScript(scriptPubKey, scriptPubKey + scriptPubKeyLen), flags, SignatureChecker(tx, nIn), NULL);
+    } catch (std::exception &e) {
+        return set_error(err, bitcoinconsensus_ERR_TX_DESERIALIZE); // Error deserializing
+    }
+}
+
+unsigned int bitcoinconsensus_version()
+{
+    // Just use the API version for now
+    return BITCOINCONSENSUS_API_VER;
+}

src/script/bitcoinconsensus.h

@@ -0,0 +1,67 @@
+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2014 The Bitcoin developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_BITCOINCONSENSUS_H
+#define BITCOIN_BITCOINCONSENSUS_H
+
+#if defined(BUILD_BITCOIN_INTERNAL) && defined(HAVE_CONFIG_H)
+#include "config/bitcoin-config.h"
+  #if defined(_WIN32)
+    #if defined(DLL_EXPORT)
+      #if defined(HAVE_FUNC_ATTRIBUTE_DLLEXPORT)
+        #define EXPORT_SYMBOL __declspec(dllexport)
+      #else
+        #define EXPORT_SYMBOL
+      #endif
+    #endif
+  #elif defined(HAVE_FUNC_ATTRIBUTE_VISIBILITY)
+    #define EXPORT_SYMBOL __attribute__ ((visibility ("default")))
+  #endif
+#elif defined(MSC_VER) && !defined(STATIC_LIBBITCOINCONSENSUS)
+  #define EXPORT_SYMBOL __declspec(dllimport)
+#endif
+
+#ifndef EXPORT_SYMBOL
+  #define EXPORT_SYMBOL
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define BITCOINCONSENSUS_API_VER 0
+
+typedef enum bitcoinconsensus_error_t
+{
+    bitcoinconsensus_ERR_OK = 0,
+    bitcoinconsensus_ERR_TX_INDEX,
+    bitcoinconsensus_ERR_TX_SIZE_MISMATCH,
+    bitcoinconsensus_ERR_TX_DESERIALIZE,
+} bitcoinconsensus_error;
+
+/** Script verification flags */
+enum
+{
+    bitcoinconsensus_SCRIPT_FLAGS_VERIFY_NONE      = 0,
+    bitcoinconsensus_SCRIPT_FLAGS_VERIFY_P2SH      = (1U << 0), // evaluate P2SH (BIP16) subscripts
+};
+
+/// Returns 1 if the input nIn of the serialized transaction pointed to by
+/// txTo correctly spends the scriptPubKey pointed to by scriptPubKey under
+/// the additional constraints specified by flags.
+/// If not NULL, err will contain an error/success code for the operation
+EXPORT_SYMBOL int bitcoinconsensus_verify_script(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen,
+                                    const unsigned char *txTo        , unsigned int txToLen,
+                                    unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err);
+
+EXPORT_SYMBOL unsigned int bitcoinconsensus_version();
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#undef EXPORT_SYMBOL
+
+#endif // BITCOIN_BITCOINCONSENSUS_H