Merge pull request #2336 from petertodd/invalid-opcode-coverage

[VerusCoin.git] / src / script.h

diff --git a/src/script.h b/src/script.h
index fdcf802945317fb6a1894f968f0ad93ded5ad3fb..4b29f6273c9f066a2bf924f5cb79e29cf9e39d9c 100644 (file)
--- a/src/script.h
+++ b/src/script.h
@@ -14,8 +14,11 @@
 #include "keystore.h"
 #include "bignum.h"
 
+class CCoins;
 class CTransaction;
 
+static const unsigned int MAX_SCRIPT_ELEMENT_SIZE = 520; // bytes
+
 /** Signature hash types/flags */
 enum
 {
@@ -25,6 +28,14 @@ enum
     SIGHASH_ANYONECANPAY = 0x80,
 };
 
+/** Script verification flags */
+enum
+{
+    SCRIPT_VERIFY_NONE      = 0,
+    SCRIPT_VERIFY_P2SH      = (1U << 0),
+    SCRIPT_VERIFY_STRICTENC = (1U << 1),
+    SCRIPT_VERIFY_NOCACHE   = (1U << 2),
+};
 
 enum txnouttype
 {
@@ -426,7 +437,7 @@ public:
         // Immediate operand
         if (opcode <= OP_PUSHDATA4)
         {
-            unsigned int nSize;
+            unsigned int nSize = 0;
             if (opcode < OP_PUSHDATA1)
             {
                 nSize = opcode;
@@ -579,11 +590,83 @@ public:
     }
 };
 
+/** Compact serializer for scripts.
+ *
+ *  It detects common cases and encodes them much more efficiently.
+ *  3 special cases are defined:
+ *  * Pay to pubkey hash (encoded as 21 bytes)
+ *  * Pay to script hash (encoded as 21 bytes)
+ *  * Pay to pubkey starting with 0x02, 0x03 or 0x04 (encoded as 33 bytes)
+ *
+ *  Other scripts up to 121 bytes require 1 byte + script length. Above
+ *  that, scripts up to 16505 bytes require 2 bytes + script length.
+ */
+class CScriptCompressor
+{
+private:
+    // make this static for now (there are only 6 special scripts defined)
+    // this can potentially be extended together with a new nVersion for
+    // transactions, in which case this value becomes dependent on nVersion
+    // and nHeight of the enclosing transaction.
+    static const unsigned int nSpecialScripts = 6;
+
+    CScript &script;
+protected:
+    // These check for scripts for which a special case with a shorter encoding is defined.
+    // They are implemented separately from the CScript test, as these test for exact byte
+    // sequence correspondences, and are more strict. For example, IsToPubKey also verifies
+    // whether the public key is valid (as invalid ones cannot be represented in compressed
+    // form).
+    bool IsToKeyID(CKeyID &hash) const;
+    bool IsToScriptID(CScriptID &hash) const;
+    bool IsToPubKey(std::vector<unsigned char> &pubkey) const;
+
+    bool Compress(std::vector<unsigned char> &out) const;
+    unsigned int GetSpecialSize(unsigned int nSize) const;
+    bool Decompress(unsigned int nSize, const std::vector<unsigned char> &out);
+public:
+    CScriptCompressor(CScript &scriptIn) : script(scriptIn) { }
+
+    unsigned int GetSerializeSize(int nType, int nVersion) const {
+        std::vector<unsigned char> compr;
+        if (Compress(compr))
+            return compr.size();
+        unsigned int nSize = script.size() + nSpecialScripts;
+        return script.size() + VARINT(nSize).GetSerializeSize(nType, nVersion);
+    }
 
+    template<typename Stream>
+    void Serialize(Stream &s, int nType, int nVersion) const {
+        std::vector<unsigned char> compr;
+        if (Compress(compr)) {
+            s << CFlatData(&compr[0], &compr[compr.size()]);
+            return;
+        }
+        unsigned int nSize = script.size() + nSpecialScripts;
+        s << VARINT(nSize);
+        s << CFlatData(&script[0], &script[script.size()]);
+    }
 
+    template<typename Stream>
+    void Unserialize(Stream &s, int nType, int nVersion) {
+        unsigned int nSize = 0;
+        s >> VARINT(nSize);
+        if (nSize < nSpecialScripts) {
+            std::vector<unsigned char> vch(GetSpecialSize(nSize), 0x00);
+            s >> REF(CFlatData(&vch[0], &vch[vch.size()]));
+            Decompress(nSize, vch);
+            return;
+        }
+        nSize -= nSpecialScripts;
+        script.resize(nSize);
+        s >> REF(CFlatData(&script[0], &script[script.size()]));
+    }
+};
 
+bool IsCanonicalPubKey(const std::vector<unsigned char> &vchPubKey);
+bool IsCanonicalSignature(const std::vector<unsigned char> &vchSig);
 
-bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, int nHashType);
+bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, unsigned int flags, int nHashType);
 bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, std::vector<std::vector<unsigned char> >& vSolutionsRet);
 int ScriptSigArgsExpected(txnouttype t, const std::vector<std::vector<unsigned char> >& vSolutions);
 bool IsStandard(const CScript& scriptPubKey);
@@ -593,9 +676,7 @@ bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet)
 bool ExtractDestinations(const CScript& scriptPubKey, txnouttype& typeRet, std::vector<CTxDestination>& addressRet, int& nRequiredRet);
 bool SignSignature(const CKeyStore& keystore, const CScript& fromPubKey, CTransaction& txTo, unsigned int nIn, int nHashType=SIGHASH_ALL);
 bool SignSignature(const CKeyStore& keystore, const CTransaction& txFrom, CTransaction& txTo, unsigned int nIn, int nHashType=SIGHASH_ALL);
-bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn,
-                  bool fValidatePayToScriptHash, int nHashType);
-bool VerifySignature(const CTransaction& txFrom, const CTransaction& txTo, unsigned int nIn, bool fValidatePayToScriptHash, int nHashType);
+bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn, unsigned int flags, int nHashType);
 
 // Given two sets of signatures for scriptPubKey, possibly with OP_0 placeholders,
 // combine them intelligently and return the result.