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-rw-r--r--src/script.cpp451
1 files changed, 233 insertions, 218 deletions
diff --git a/src/script.cpp b/src/script.cpp
index 4357a9a1b..cf6eeaf39 100644
--- a/src/script.cpp
+++ b/src/script.cpp
@@ -9,14 +9,14 @@ using namespace std;
using namespace boost;
#include "script.h"
+#include "core.h"
#include "keystore.h"
#include "bignum.h"
#include "key.h"
-#include "main.h"
#include "sync.h"
#include "util.h"
-bool CheckSig(vector<unsigned char> vchSig, vector<unsigned char> vchPubKey, CScript scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType);
+bool CheckSig(vector<unsigned char> vchSig, const vector<unsigned char> &vchPubKey, const CScript &scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType, int flags);
@@ -54,32 +54,6 @@ bool CastToBool(const valtype& vch)
return false;
}
-//
-// WARNING: This does not work as expected for signed integers; the sign-bit
-// is left in place as the integer is zero-extended. The correct behavior
-// would be to move the most significant bit of the last byte during the
-// resize process. MakeSameSize() is currently only used by the disabled
-// opcodes OP_AND, OP_OR, and OP_XOR.
-//
-void MakeSameSize(valtype& vch1, valtype& vch2)
-{
- // Lengthen the shorter one
- if (vch1.size() < vch2.size())
- // PATCH:
- // +unsigned char msb = vch1[vch1.size()-1];
- // +vch1[vch1.size()-1] &= 0x7f;
- // vch1.resize(vch2.size(), 0);
- // +vch1[vch1.size()-1] = msb;
- vch1.resize(vch2.size(), 0);
- if (vch2.size() < vch1.size())
- // PATCH:
- // +unsigned char msb = vch2[vch2.size()-1];
- // +vch2[vch2.size()-1] &= 0x7f;
- // vch2.resize(vch1.size(), 0);
- // +vch2[vch2.size()-1] = msb;
- vch2.resize(vch1.size(), 0);
-}
-
//
@@ -253,7 +227,69 @@ const char* GetOpName(opcodetype opcode)
}
}
-bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, int nHashType)
+bool IsCanonicalPubKey(const valtype &vchPubKey) {
+ if (vchPubKey.size() < 33)
+ return error("Non-canonical public key: too short");
+ if (vchPubKey[0] == 0x04) {
+ if (vchPubKey.size() != 65)
+ return error("Non-canonical public key: invalid length for uncompressed key");
+ } else if (vchPubKey[0] == 0x02 || vchPubKey[0] == 0x03) {
+ if (vchPubKey.size() != 33)
+ return error("Non-canonical public key: invalid length for compressed key");
+ } else {
+ return error("Non-canonical public key: compressed nor uncompressed");
+ }
+ return true;
+}
+
+bool IsCanonicalSignature(const valtype &vchSig) {
+ // See https://bitcointalk.org/index.php?topic=8392.msg127623#msg127623
+ // A canonical signature exists of: <30> <total len> <02> <len R> <R> <02> <len S> <S> <hashtype>
+ // Where R and S are not negative (their first byte has its highest bit not set), and not
+ // excessively padded (do not start with a 0 byte, unless an otherwise negative number follows,
+ // in which case a single 0 byte is necessary and even required).
+ if (vchSig.size() < 9)
+ return error("Non-canonical signature: too short");
+ if (vchSig.size() > 73)
+ return error("Non-canonical signature: too long");
+ unsigned char nHashType = vchSig[vchSig.size() - 1] & (~(SIGHASH_ANYONECANPAY));
+ if (nHashType < SIGHASH_ALL || nHashType > SIGHASH_SINGLE)
+ return error("Non-canonical signature: unknown hashtype byte");
+ if (vchSig[0] != 0x30)
+ return error("Non-canonical signature: wrong type");
+ if (vchSig[1] != vchSig.size()-3)
+ return error("Non-canonical signature: wrong length marker");
+ unsigned int nLenR = vchSig[3];
+ if (5 + nLenR >= vchSig.size())
+ return error("Non-canonical signature: S length misplaced");
+ unsigned int nLenS = vchSig[5+nLenR];
+ if ((unsigned long)(nLenR+nLenS+7) != vchSig.size())
+ return error("Non-canonical signature: R+S length mismatch");
+
+ const unsigned char *R = &vchSig[4];
+ if (R[-2] != 0x02)
+ return error("Non-canonical signature: R value type mismatch");
+ if (nLenR == 0)
+ return error("Non-canonical signature: R length is zero");
+ if (R[0] & 0x80)
+ return error("Non-canonical signature: R value negative");
+ if (nLenR > 1 && (R[0] == 0x00) && !(R[1] & 0x80))
+ return error("Non-canonical signature: R value excessively padded");
+
+ const unsigned char *S = &vchSig[6+nLenR];
+ if (S[-2] != 0x02)
+ return error("Non-canonical signature: S value type mismatch");
+ if (nLenS == 0)
+ return error("Non-canonical signature: S length is zero");
+ if (S[0] & 0x80)
+ return error("Non-canonical signature: S value negative");
+ if (nLenS > 1 && (S[0] == 0x00) && !(S[1] & 0x80))
+ return error("Non-canonical signature: S value excessively padded");
+
+ return true;
+}
+
+bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, unsigned int flags, int nHashType)
{
CAutoBN_CTX pctx;
CScript::const_iterator pc = script.begin();
@@ -266,7 +302,7 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, co
if (script.size() > 10000)
return false;
int nOpCount = 0;
-
+ bool fStrictEncodings = flags & SCRIPT_VERIFY_STRICTENC;
try
{
@@ -279,7 +315,7 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, co
//
if (!script.GetOp(pc, opcode, vchPushValue))
return false;
- if (vchPushValue.size() > 520)
+ if (vchPushValue.size() > MAX_SCRIPT_ELEMENT_SIZE)
return false;
if (opcode > OP_16 && ++nOpCount > 201)
return false;
@@ -299,7 +335,7 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, co
opcode == OP_MOD ||
opcode == OP_LSHIFT ||
opcode == OP_RSHIFT)
- return false;
+ return false; // Disabled opcodes.
if (fExec && 0 <= opcode && opcode <= OP_PUSHDATA4)
stack.push_back(vchPushValue);
@@ -597,64 +633,6 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, co
break;
- //
- // Splice ops
- //
- case OP_CAT:
- {
- // (x1 x2 -- out)
- if (stack.size() < 2)
- return false;
- valtype& vch1 = stacktop(-2);
- valtype& vch2 = stacktop(-1);
- vch1.insert(vch1.end(), vch2.begin(), vch2.end());
- popstack(stack);
- if (stacktop(-1).size() > 520)
- return false;
- }
- break;
-
- case OP_SUBSTR:
- {
- // (in begin size -- out)
- if (stack.size() < 3)
- return false;
- valtype& vch = stacktop(-3);
- int nBegin = CastToBigNum(stacktop(-2)).getint();
- int nEnd = nBegin + CastToBigNum(stacktop(-1)).getint();
- if (nBegin < 0 || nEnd < nBegin)
- return false;
- if (nBegin > (int)vch.size())
- nBegin = vch.size();
- if (nEnd > (int)vch.size())
- nEnd = vch.size();
- vch.erase(vch.begin() + nEnd, vch.end());
- vch.erase(vch.begin(), vch.begin() + nBegin);
- popstack(stack);
- popstack(stack);
- }
- break;
-
- case OP_LEFT:
- case OP_RIGHT:
- {
- // (in size -- out)
- if (stack.size() < 2)
- return false;
- valtype& vch = stacktop(-2);
- int nSize = CastToBigNum(stacktop(-1)).getint();
- if (nSize < 0)
- return false;
- if (nSize > (int)vch.size())
- nSize = vch.size();
- if (opcode == OP_LEFT)
- vch.erase(vch.begin() + nSize, vch.end());
- else
- vch.erase(vch.begin(), vch.end() - nSize);
- popstack(stack);
- }
- break;
-
case OP_SIZE:
{
// (in -- in size)
@@ -669,51 +647,6 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, co
//
// Bitwise logic
//
- case OP_INVERT:
- {
- // (in - out)
- if (stack.size() < 1)
- return false;
- valtype& vch = stacktop(-1);
- for (unsigned int i = 0; i < vch.size(); i++)
- vch[i] = ~vch[i];
- }
- break;
-
- //
- // WARNING: These disabled opcodes exhibit unexpected behavior
- // when used on signed integers due to a bug in MakeSameSize()
- // [see definition of MakeSameSize() above].
- //
- case OP_AND:
- case OP_OR:
- case OP_XOR:
- {
- // (x1 x2 - out)
- if (stack.size() < 2)
- return false;
- valtype& vch1 = stacktop(-2);
- valtype& vch2 = stacktop(-1);
- MakeSameSize(vch1, vch2); // <-- NOT SAFE FOR SIGNED VALUES
- if (opcode == OP_AND)
- {
- for (unsigned int i = 0; i < vch1.size(); i++)
- vch1[i] &= vch2[i];
- }
- else if (opcode == OP_OR)
- {
- for (unsigned int i = 0; i < vch1.size(); i++)
- vch1[i] |= vch2[i];
- }
- else if (opcode == OP_XOR)
- {
- for (unsigned int i = 0; i < vch1.size(); i++)
- vch1[i] ^= vch2[i];
- }
- popstack(stack);
- }
- break;
-
case OP_EQUAL:
case OP_EQUALVERIFY:
//case OP_NOTEQUAL: // use OP_NUMNOTEQUAL
@@ -748,8 +681,6 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, co
//
case OP_1ADD:
case OP_1SUB:
- case OP_2MUL:
- case OP_2DIV:
case OP_NEGATE:
case OP_ABS:
case OP_NOT:
@@ -763,8 +694,6 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, co
{
case OP_1ADD: bn += bnOne; break;
case OP_1SUB: bn -= bnOne; break;
- case OP_2MUL: bn <<= 1; break;
- case OP_2DIV: bn >>= 1; break;
case OP_NEGATE: bn = -bn; break;
case OP_ABS: if (bn < bnZero) bn = -bn; break;
case OP_NOT: bn = (bn == bnZero); break;
@@ -778,11 +707,6 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, co
case OP_ADD:
case OP_SUB:
- case OP_MUL:
- case OP_DIV:
- case OP_MOD:
- case OP_LSHIFT:
- case OP_RSHIFT:
case OP_BOOLAND:
case OP_BOOLOR:
case OP_NUMEQUAL:
@@ -811,33 +735,6 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, co
bn = bn1 - bn2;
break;
- case OP_MUL:
- if (!BN_mul(&bn, &bn1, &bn2, pctx))
- return false;
- break;
-
- case OP_DIV:
- if (!BN_div(&bn, NULL, &bn1, &bn2, pctx))
- return false;
- break;
-
- case OP_MOD:
- if (!BN_mod(&bn, &bn1, &bn2, pctx))
- return false;
- break;
-
- case OP_LSHIFT:
- if (bn2 < bnZero || bn2 > CBigNum(2048))
- return false;
- bn = bn1 << bn2.getulong();
- break;
-
- case OP_RSHIFT:
- if (bn2 < bnZero || bn2 > CBigNum(2048))
- return false;
- bn = bn1 >> bn2.getulong();
- break;
-
case OP_BOOLAND: bn = (bn1 != bnZero && bn2 != bnZero); break;
case OP_BOOLOR: bn = (bn1 != bnZero || bn2 != bnZero); break;
case OP_NUMEQUAL: bn = (bn1 == bn2); break;
@@ -944,7 +841,9 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, co
// Drop the signature, since there's no way for a signature to sign itself
scriptCode.FindAndDelete(CScript(vchSig));
- bool fSuccess = CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType);
+ bool fSuccess = (!fStrictEncodings || (IsCanonicalSignature(vchSig) && IsCanonicalPubKey(vchPubKey)));
+ if (fSuccess)
+ fSuccess = CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType, flags);
popstack(stack);
popstack(stack);
@@ -1004,8 +903,11 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, co
valtype& vchPubKey = stacktop(-ikey);
// Check signature
- if (CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType))
- {
+ bool fOk = (!fStrictEncodings || (IsCanonicalSignature(vchSig) && IsCanonicalPubKey(vchPubKey)));
+ if (fOk)
+ fOk = CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType, flags);
+
+ if (fOk) {
isig++;
nSigsCount--;
}
@@ -1117,10 +1019,9 @@ uint256 SignatureHash(CScript scriptCode, const CTransaction& txTo, unsigned int
}
// Serialize and hash
- CDataStream ss(SER_GETHASH, 0);
- ss.reserve(10000);
+ CHashWriter ss(SER_GETHASH, 0);
ss << txTmp << nHashType;
- return Hash(ss.begin(), ss.end());
+ return ss.GetHash();
}
@@ -1132,15 +1033,15 @@ class CSignatureCache
{
private:
// sigdata_type is (signature hash, signature, public key):
- typedef boost::tuple<uint256, std::vector<unsigned char>, std::vector<unsigned char> > sigdata_type;
+ typedef boost::tuple<uint256, std::vector<unsigned char>, CPubKey> sigdata_type;
std::set< sigdata_type> setValid;
- CCriticalSection cs_sigcache;
+ boost::shared_mutex cs_sigcache;
public:
bool
- Get(uint256 hash, const std::vector<unsigned char>& vchSig, const std::vector<unsigned char>& pubKey)
+ Get(const uint256 &hash, const std::vector<unsigned char>& vchSig, const CPubKey& pubKey)
{
- LOCK(cs_sigcache);
+ boost::shared_lock<boost::shared_mutex> lock(cs_sigcache);
sigdata_type k(hash, vchSig, pubKey);
std::set<sigdata_type>::iterator mi = setValid.find(k);
@@ -1149,7 +1050,7 @@ public:
return false;
}
- void Set(uint256 hash, const std::vector<unsigned char>& vchSig, const std::vector<unsigned char>& pubKey)
+ void Set(const uint256 &hash, const std::vector<unsigned char>& vchSig, const CPubKey& pubKey)
{
// DoS prevention: limit cache size to less than 10MB
// (~200 bytes per cache entry times 50,000 entries)
@@ -1158,7 +1059,7 @@ public:
int64 nMaxCacheSize = GetArg("-maxsigcachesize", 50000);
if (nMaxCacheSize <= 0) return;
- LOCK(cs_sigcache);
+ boost::unique_lock<boost::shared_mutex> lock(cs_sigcache);
while (static_cast<int64>(setValid.size()) > nMaxCacheSize)
{
@@ -1180,11 +1081,15 @@ public:
}
};
-bool CheckSig(vector<unsigned char> vchSig, vector<unsigned char> vchPubKey, CScript scriptCode,
- const CTransaction& txTo, unsigned int nIn, int nHashType)
+bool CheckSig(vector<unsigned char> vchSig, const vector<unsigned char> &vchPubKey, const CScript &scriptCode,
+ const CTransaction& txTo, unsigned int nIn, int nHashType, int flags)
{
static CSignatureCache signatureCache;
+ CPubKey pubkey(vchPubKey);
+ if (!pubkey.IsValid())
+ return false;
+
// Hash type is one byte tacked on to the end of the signature
if (vchSig.empty())
return false;
@@ -1196,17 +1101,15 @@ bool CheckSig(vector<unsigned char> vchSig, vector<unsigned char> vchPubKey, CSc
uint256 sighash = SignatureHash(scriptCode, txTo, nIn, nHashType);
- if (signatureCache.Get(sighash, vchSig, vchPubKey))
+ if (signatureCache.Get(sighash, vchSig, pubkey))
return true;
- CKey key;
- if (!key.SetPubKey(vchPubKey))
+ if (!pubkey.Verify(sighash, vchSig))
return false;
- if (!key.Verify(sighash, vchSig))
- return false;
+ if (!(flags & SCRIPT_VERIFY_NOCACHE))
+ signatureCache.Set(sighash, vchSig, pubkey);
- signatureCache.Set(sighash, vchSig, vchPubKey);
return true;
}
@@ -1572,14 +1475,14 @@ bool ExtractDestinations(const CScript& scriptPubKey, txnouttype& typeRet, vecto
}
bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn,
- bool fValidatePayToScriptHash, int nHashType)
+ unsigned int flags, int nHashType)
{
vector<vector<unsigned char> > stack, stackCopy;
- if (!EvalScript(stack, scriptSig, txTo, nIn, nHashType))
+ if (!EvalScript(stack, scriptSig, txTo, nIn, flags, nHashType))
return false;
- if (fValidatePayToScriptHash)
+ if (flags & SCRIPT_VERIFY_P2SH)
stackCopy = stack;
- if (!EvalScript(stack, scriptPubKey, txTo, nIn, nHashType))
+ if (!EvalScript(stack, scriptPubKey, txTo, nIn, flags, nHashType))
return false;
if (stack.empty())
return false;
@@ -1588,16 +1491,21 @@ bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const C
return false;
// Additional validation for spend-to-script-hash transactions:
- if (fValidatePayToScriptHash && scriptPubKey.IsPayToScriptHash())
+ if ((flags & SCRIPT_VERIFY_P2SH) && scriptPubKey.IsPayToScriptHash())
{
if (!scriptSig.IsPushOnly()) // scriptSig must be literals-only
return false; // or validation fails
+ // stackCopy cannot be empty here, because if it was the
+ // P2SH HASH <> EQUAL scriptPubKey would be evaluated with
+ // an empty stack and the EvalScript above would return false.
+ assert(!stackCopy.empty());
+
const valtype& pubKeySerialized = stackCopy.back();
CScript pubKey2(pubKeySerialized.begin(), pubKeySerialized.end());
popstack(stackCopy);
- if (!EvalScript(stackCopy, pubKey2, txTo, nIn, nHashType))
+ if (!EvalScript(stackCopy, pubKey2, txTo, nIn, flags, nHashType))
return false;
if (stackCopy.empty())
return false;
@@ -1640,7 +1548,7 @@ bool SignSignature(const CKeyStore &keystore, const CScript& fromPubKey, CTransa
}
// Test solution
- return VerifyScript(txin.scriptSig, fromPubKey, txTo, nIn, true, 0);
+ return VerifyScript(txin.scriptSig, fromPubKey, txTo, nIn, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_STRICTENC, 0);
}
bool SignSignature(const CKeyStore &keystore, const CTransaction& txFrom, CTransaction& txTo, unsigned int nIn, int nHashType)
@@ -1653,20 +1561,6 @@ bool SignSignature(const CKeyStore &keystore, const CTransaction& txFrom, CTrans
return SignSignature(keystore, txout.scriptPubKey, txTo, nIn, nHashType);
}
-bool VerifySignature(const CTransaction& txFrom, const CTransaction& txTo, unsigned int nIn, bool fValidatePayToScriptHash, int nHashType)
-{
- assert(nIn < txTo.vin.size());
- const CTxIn& txin = txTo.vin[nIn];
- if (txin.prevout.n >= txFrom.vout.size())
- return false;
- const CTxOut& txout = txFrom.vout[txin.prevout.n];
-
- if (txin.prevout.hash != txFrom.GetHash())
- return false;
-
- return VerifyScript(txin.scriptSig, txout.scriptPubKey, txTo, nIn, fValidatePayToScriptHash, nHashType);
-}
-
static CScript PushAll(const vector<valtype>& values)
{
CScript result;
@@ -1705,7 +1599,7 @@ static CScript CombineMultisig(CScript scriptPubKey, const CTransaction& txTo, u
if (sigs.count(pubkey))
continue; // Already got a sig for this pubkey
- if (CheckSig(sig, pubkey, scriptPubKey, txTo, nIn, 0))
+ if (CheckSig(sig, pubkey, scriptPubKey, txTo, nIn, 0, 0))
{
sigs[pubkey] = sig;
break;
@@ -1782,9 +1676,9 @@ CScript CombineSignatures(CScript scriptPubKey, const CTransaction& txTo, unsign
Solver(scriptPubKey, txType, vSolutions);
vector<valtype> stack1;
- EvalScript(stack1, scriptSig1, CTransaction(), 0, 0);
+ EvalScript(stack1, scriptSig1, CTransaction(), 0, SCRIPT_VERIFY_STRICTENC, 0);
vector<valtype> stack2;
- EvalScript(stack2, scriptSig2, CTransaction(), 0, 0);
+ EvalScript(stack2, scriptSig2, CTransaction(), 0, SCRIPT_VERIFY_STRICTENC, 0);
return CombineSignatures(scriptPubKey, txTo, nIn, txType, vSolutions, stack1, stack2);
}
@@ -1876,12 +1770,133 @@ void CScript::SetDestination(const CTxDestination& dest)
boost::apply_visitor(CScriptVisitor(this), dest);
}
-void CScript::SetMultisig(int nRequired, const std::vector<CKey>& keys)
+void CScript::SetMultisig(int nRequired, const std::vector<CPubKey>& keys)
{
this->clear();
*this << EncodeOP_N(nRequired);
- BOOST_FOREACH(const CKey& key, keys)
- *this << key.GetPubKey();
+ BOOST_FOREACH(const CPubKey& key, keys)
+ *this << key;
*this << EncodeOP_N(keys.size()) << OP_CHECKMULTISIG;
}
+
+bool CScriptCompressor::IsToKeyID(CKeyID &hash) const
+{
+ if (script.size() == 25 && script[0] == OP_DUP && script[1] == OP_HASH160
+ && script[2] == 20 && script[23] == OP_EQUALVERIFY
+ && script[24] == OP_CHECKSIG) {
+ memcpy(&hash, &script[3], 20);
+ return true;
+ }
+ return false;
+}
+
+bool CScriptCompressor::IsToScriptID(CScriptID &hash) const
+{
+ if (script.size() == 23 && script[0] == OP_HASH160 && script[1] == 20
+ && script[22] == OP_EQUAL) {
+ memcpy(&hash, &script[2], 20);
+ return true;
+ }
+ return false;
+}
+
+bool CScriptCompressor::IsToPubKey(CPubKey &pubkey) const
+{
+ if (script.size() == 35 && script[0] == 33 && script[34] == OP_CHECKSIG
+ && (script[1] == 0x02 || script[1] == 0x03)) {
+ pubkey.Set(&script[1], &script[34]);
+ return true;
+ }
+ if (script.size() == 67 && script[0] == 65 && script[66] == OP_CHECKSIG
+ && script[1] == 0x04) {
+ pubkey.Set(&script[1], &script[66]);
+ return pubkey.IsFullyValid(); // if not fully valid, a case that would not be compressible
+ }
+ return false;
+}
+
+bool CScriptCompressor::Compress(std::vector<unsigned char> &out) const
+{
+ CKeyID keyID;
+ if (IsToKeyID(keyID)) {
+ out.resize(21);
+ out[0] = 0x00;
+ memcpy(&out[1], &keyID, 20);
+ return true;
+ }
+ CScriptID scriptID;
+ if (IsToScriptID(scriptID)) {
+ out.resize(21);
+ out[0] = 0x01;
+ memcpy(&out[1], &scriptID, 20);
+ return true;
+ }
+ CPubKey pubkey;
+ if (IsToPubKey(pubkey)) {
+ out.resize(33);
+ memcpy(&out[1], &pubkey[1], 32);
+ if (pubkey[0] == 0x02 || pubkey[0] == 0x03) {
+ out[0] = pubkey[0];
+ return true;
+ } else if (pubkey[0] == 0x04) {
+ out[0] = 0x04 | (pubkey[64] & 0x01);
+ return true;
+ }
+ }
+ return false;
+}
+
+unsigned int CScriptCompressor::GetSpecialSize(unsigned int nSize) const
+{
+ if (nSize == 0 || nSize == 1)
+ return 20;
+ if (nSize == 2 || nSize == 3 || nSize == 4 || nSize == 5)
+ return 32;
+ return 0;
+}
+
+bool CScriptCompressor::Decompress(unsigned int nSize, const std::vector<unsigned char> &in)
+{
+ switch(nSize) {
+ case 0x00:
+ script.resize(25);
+ script[0] = OP_DUP;
+ script[1] = OP_HASH160;
+ script[2] = 20;
+ memcpy(&script[3], &in[0], 20);
+ script[23] = OP_EQUALVERIFY;
+ script[24] = OP_CHECKSIG;
+ return true;
+ case 0x01:
+ script.resize(23);
+ script[0] = OP_HASH160;
+ script[1] = 20;
+ memcpy(&script[2], &in[0], 20);
+ script[22] = OP_EQUAL;
+ return true;
+ case 0x02:
+ case 0x03:
+ script.resize(35);
+ script[0] = 33;
+ script[1] = nSize;
+ memcpy(&script[2], &in[0], 32);
+ script[34] = OP_CHECKSIG;
+ return true;
+ case 0x04:
+ case 0x05:
+ unsigned char vch[33] = {};
+ vch[0] = nSize - 2;
+ memcpy(&vch[1], &in[0], 32);
+ CPubKey pubkey(&vch[0], &vch[33]);
+ if (!pubkey.Decompress())
+ return false;
+ assert(pubkey.size() == 65);
+ script.resize(67);
+ script[0] = 65;
+ memcpy(&script[1], pubkey.begin(), 65);
+ script[66] = OP_CHECKSIG;
+ return true;
+ }
+ return false;
+}