#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);
static const valtype vchFalse(0);
static const valtype vchZero(0);
}
}
-bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, int nHashType)
+bool IsCanonicalPubKey(const valtype &vchPubKey, unsigned int flags) {
+ if (!(flags & SCRIPT_VERIFY_STRICTENC))
+ return true;
+
+ 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, unsigned int flags) {
+ if (!(flags & SCRIPT_VERIFY_STRICTENC))
+ return true;
+
+ // 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");
+
+ if (flags & SCRIPT_VERIFY_EVEN_S) {
+ if (S[nLenS-1] & 1)
+ return error("Non-canonical signature: S value odd");
+ }
+
+ 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();
return false;
int nOpCount = 0;
-
try
{
while (pc < pend)
//
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;
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);
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)
//
// 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
//
case OP_1ADD:
case OP_1SUB:
- case OP_2MUL:
- case OP_2DIV:
case OP_NEGATE:
case OP_ABS:
case OP_NOT:
{
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;
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:
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;
// 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 = IsCanonicalSignature(vchSig, flags) && IsCanonicalPubKey(vchPubKey, flags) &&
+ CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType, flags);
popstack(stack);
popstack(stack);
valtype& vchPubKey = stacktop(-ikey);
// Check signature
- if (CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType))
- {
+ bool fOk = IsCanonicalSignature(vchSig, flags) && IsCanonicalPubKey(vchPubKey, flags) &&
+ CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType, flags);
+
+ if (fOk) {
isig++;
nSigsCount--;
}
fSuccess = false;
}
- while (i-- > 0)
+ while (i-- > 1)
popstack(stack);
+
+ // A bug causes CHECKMULTISIG to consume one extra argument
+ // whose contents were not checked in any way.
+ //
+ // Unfortunately this is a potential source of mutability,
+ // so optionally verify it is exactly equal to zero prior
+ // to removing it from the stack.
+ if (stack.size() < 1)
+ return false;
+ if ((flags & SCRIPT_VERIFY_NULLDUMMY) && stacktop(-1).size())
+ return error("CHECKMULTISIG dummy argument not null");
+ popstack(stack);
+
stack.push_back(fSuccess ? vchTrue : vchFalse);
if (opcode == OP_CHECKMULTISIGVERIFY)
{
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;
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);
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)
}
};
-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;
+ CKey key;
+ if (!key.SetPubKey(vchPubKey))
+ return false;
+ CPubKey pubkey = key.GetPubKey();
+ if (!pubkey.IsValid())
+ return false;
+
// Hash type is one byte tacked on to the end of the signature
if (vchSig.empty())
return false;
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))
- return false;
-
if (!key.Verify(sighash, vchSig))
return false;
- signatureCache.Set(sighash, vchSig, vchPubKey);
+ if (!(flags & SCRIPT_VERIFY_NOCACHE))
+ signatureCache.Set(sighash, vchSig, pubkey);
+
return true;
}
-
//
// Return public keys or hashes from scriptPubKey, for 'standard' transaction types.
//
}
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;
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;
return true;
}
-
bool SignSignature(const CKeyStore &keystore, const CScript& fromPubKey, CTransaction& txTo, unsigned int nIn, int nHashType)
{
assert(nIn < txTo.vin.size());
}
// Test solution
- return VerifyScript(txin.scriptSig, fromPubKey, txTo, nIn, true, 0);
+ return VerifyScript(txin.scriptSig, fromPubKey, txTo, nIn, STANDARD_SCRIPT_VERIFY_FLAGS, 0);
}
bool SignSignature(const CKeyStore &keystore, const CTransaction& txFrom, CTransaction& txTo, unsigned int nIn, int nHashType)
return SignSignature(keystore, txout.scriptPubKey, txTo, nIn, nHashType);
}
-bool VerifySignature(const CTransaction& txFrom, const CTransaction& txTo, unsigned int nIn, bool fValidatePayToScriptHash, int nHashType)
+bool VerifySignature(const CTransaction& txFrom, const CTransaction& txTo, unsigned int nIn, unsigned int flags, int nHashType)
{
assert(nIn < txTo.vin.size());
const CTxIn& txin = txTo.vin[nIn];
if (txin.prevout.hash != txFrom.GetHash())
return false;
- return VerifyScript(txin.scriptSig, txout.scriptPubKey, txTo, nIn, fValidatePayToScriptHash, nHashType);
+ return VerifyScript(txin.scriptSig, txout.scriptPubKey, txTo, nIn, flags, nHashType);
}
static CScript PushAll(const vector<valtype>& values)
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;
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);
}
git://git.novaco.in / novacoin.git / blobdiff