Merge #14696: qa: Add explicit references to related CVE's in p2p_invalid_block test.

0c62e3a New regression testing for CVE-2018-17144, CVE-2012-2459, and CVE-2010-5137. (lucash-dev)
38bfca6 Added comments referencing multiple CVEs in tests and production code. (lucash-dev)

Pull request description:

  This functional test includes two scenarios that test for regressions of vulnerabilities, but they are only briefly described. There are freely available documents explaining in detail the issues, but without explicit mentions, the developer trying to maintain the code needs an additional step of digging in commit history and PR conversations to figure it out.
  Added comments to explicitly mention  CVE-2018-17144 and CVE-2012-2459, for more complete documentation.
  This improves developer experience by making understanding the tests easier.

ACKs for top commit:
  laanwj:
    ACK 0c62e3a, checked the CVE numbers, thanks for adding documentation

Tree-SHA512: 3ee05351745193b8b959e4a25d50f25a693b2d24b0732ed53cf7d5882df40b5dd0f1877bd5c69cffb921d4a7acf9deb3cc1160b96dc730d9b5984151ad06b7c9

Author: laanwj

src/consensus/tx_check.cpp

@@ -18,7 +18,7 @@ bool CheckTransaction(const CTransaction& tx, CValidationState &state, bool fChe
     if (::GetSerializeSize(tx, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * WITNESS_SCALE_FACTOR > MAX_BLOCK_WEIGHT)
         return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-txns-oversize");
 
-    // Check for negative or overflow output values
+    // Check for negative or overflow output values (see CVE-2010-5139)
     CAmount nValueOut = 0;
     for (const auto& txout : tx.vout)
     {

src/net_processing.cpp

@@ -2559,7 +2559,7 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
                 }
                 AddOrphanTx(ptx, pfrom->GetId());
 
-                // DoS prevention: do not allow mapOrphanTransactions to grow unbounded
+                // DoS prevention: do not allow mapOrphanTransactions to grow unbounded (see CVE-2012-3789)
                 unsigned int nMaxOrphanTx = (unsigned int)std::max((int64_t)0, gArgs.GetArg("-maxorphantx", DEFAULT_MAX_ORPHAN_TRANSACTIONS));
                 unsigned int nEvicted = LimitOrphanTxSize(nMaxOrphanTx);
                 if (nEvicted > 0) {

src/script/interpreter.cpp

@@ -334,7 +334,7 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript&
                 opcode == OP_MOD ||
                 opcode == OP_LSHIFT ||
                 opcode == OP_RSHIFT)
-                return set_error(serror, SCRIPT_ERR_DISABLED_OPCODE); // Disabled opcodes.
+                return set_error(serror, SCRIPT_ERR_DISABLED_OPCODE); // Disabled opcodes (CVE-2010-5137).
 
             // With SCRIPT_VERIFY_CONST_SCRIPTCODE, OP_CODESEPARATOR in non-segwit script is rejected even in an unexecuted branch
             if (opcode == OP_CODESEPARATOR && sigversion == SigVersion::BASE && (flags & SCRIPT_VERIFY_CONST_SCRIPTCODE))
@@ -1483,6 +1483,8 @@ bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const C
         return set_error(serror, SCRIPT_ERR_SIG_PUSHONLY);
     }
 
+    // scriptSig and scriptPubKey must be evaluated sequentially on the same stack
+    // rather than being simply concatenated (see CVE-2010-5141)
     std::vector<std::vector<unsigned char> > stack, stackCopy;
     if (!EvalScript(stack, scriptSig, flags, checker, SigVersion::BASE, serror))
         // serror is set

src/test/data/script_tests.json

@@ -829,15 +829,16 @@
 ["NOP", "2SWAP 1", "P2SH,STRICTENC", "INVALID_STACK_OPERATION"],
 ["1", "2 3 2SWAP 1", "P2SH,STRICTENC", "INVALID_STACK_OPERATION"],
 
+
+["NOP", "SIZE 1", "P2SH,STRICTENC", "INVALID_STACK_OPERATION"],
+
+["TEST DISABLED OP CODES (CVE-2010-5137)"],
 ["'a' 'b'", "CAT", "P2SH,STRICTENC", "DISABLED_OPCODE", "CAT disabled"],
 ["'a' 'b' 0", "IF CAT ELSE 1 ENDIF", "P2SH,STRICTENC", "DISABLED_OPCODE", "CAT disabled"],
 ["'abc' 1 1", "SUBSTR", "P2SH,STRICTENC", "DISABLED_OPCODE", "SUBSTR disabled"],
 ["'abc' 1 1 0", "IF SUBSTR ELSE 1 ENDIF", "P2SH,STRICTENC", "DISABLED_OPCODE", "SUBSTR disabled"],
 ["'abc' 2 0", "IF LEFT ELSE 1 ENDIF", "P2SH,STRICTENC", "DISABLED_OPCODE", "LEFT disabled"],
 ["'abc' 2 0", "IF RIGHT ELSE 1 ENDIF", "P2SH,STRICTENC", "DISABLED_OPCODE", "RIGHT disabled"],
-
-["NOP", "SIZE 1", "P2SH,STRICTENC", "INVALID_STACK_OPERATION"],
-
 ["'abc'", "IF INVERT ELSE 1 ENDIF", "P2SH,STRICTENC", "DISABLED_OPCODE", "INVERT disabled"],
 ["1 2 0 IF AND ELSE 1 ENDIF", "NOP", "P2SH,STRICTENC", "DISABLED_OPCODE", "AND disabled"],
 ["1 2 0 IF OR ELSE 1 ENDIF", "NOP", "P2SH,STRICTENC", "DISABLED_OPCODE", "OR disabled"],

src/validation.cpp

@@ -1828,7 +1828,7 @@ bool CChainState::ConnectBlock(const CBlock& block, CValidationState& state, CBl
     // If such overwrites are allowed, coinbases and transactions depending upon those
     // can be duplicated to remove the ability to spend the first instance -- even after
     // being sent to another address.
-    // See BIP30 and http://r6.ca/blog/20120206T005236Z.html for more information.
+    // See BIP30, CVE-2012-1909, and http://r6.ca/blog/20120206T005236Z.html for more information.
     // This logic is not necessary for memory pool transactions, as AcceptToMemoryPool
     // already refuses previously-known transaction ids entirely.
     // This rule was originally applied to all blocks with a timestamp after March 15, 2012, 0:00 UTC.
@@ -3100,6 +3100,7 @@ bool CheckBlock(const CBlock& block, CValidationState& state, const Consensus::P
             return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-cb-multiple", "more than one coinbase");
 
     // Check transactions
+    // Must check for duplicate inputs (see CVE-2018-17144)
     for (const auto& tx : block.vtx)
         if (!CheckTransaction(*tx, state, true))
             return state.Invalid(state.GetReason(), false, state.GetRejectCode(), state.GetRejectReason(),

test/functional/data/invalid_txs.py

@@ -24,7 +24,24 @@
 from test_framework.messages import CTransaction, CTxIn, CTxOut, COutPoint
 from test_framework import script as sc
 from test_framework.blocktools import create_tx_with_script, MAX_BLOCK_SIGOPS
-
+from test_framework.script import (
+    CScript,
+    OP_CAT,
+    OP_SUBSTR,
+    OP_LEFT,
+    OP_RIGHT,
+    OP_INVERT,
+    OP_AND,
+    OP_OR,
+    OP_XOR,
+    OP_2MUL,
+    OP_2DIV,
+    OP_MUL,
+    OP_DIV,
+    OP_MOD,
+    OP_LSHIFT,
+    OP_RSHIFT
+)
 basic_p2sh = sc.CScript([sc.OP_HASH160, sc.hash160(sc.CScript([sc.OP_0])), sc.OP_EQUAL])
 
 
@@ -178,7 +195,44 @@ def get_tx(self):
             script_pub_key=lotsa_checksigs,
             amount=1)
 
+def getDisabledOpcodeTemplate(opcode):
+    """ Creates disabled opcode tx template class"""
+    def get_tx(self):
+        tx = CTransaction()
+        vin = self.valid_txin
+        vin.scriptSig = CScript([opcode])
+        tx.vin.append(vin)
+        tx.vout.append(CTxOut(1, basic_p2sh))
+        tx.calc_sha256()
+        return tx
+
+    return type('DisabledOpcode_' + str(opcode), (BadTxTemplate,), {
+        'reject_reason': "disabled opcode",
+        'expect_disconnect': True,
+        'get_tx': get_tx,
+        'valid_in_block' : True
+        })
+
+# Disabled opcode tx templates (CVE-2010-5137)
+DisabledOpcodeTemplates = [getDisabledOpcodeTemplate(opcode) for opcode in [
+    OP_CAT,
+    OP_SUBSTR,
+    OP_LEFT,
+    OP_RIGHT,
+    OP_INVERT,
+    OP_AND,
+    OP_OR,
+    OP_XOR,
+    OP_2MUL,
+    OP_2DIV,
+    OP_MUL,
+    OP_DIV,
+    OP_MOD,
+    OP_LSHIFT,
+    OP_RSHIFT]]
+
 
 def iter_all_templates():
     """Iterate through all bad transaction template types."""
     return BadTxTemplate.__subclasses__()
+

test/functional/feature_block.py

@@ -806,7 +806,7 @@ def run_test(self):
         #
         # Blocks are not allowed to contain a transaction whose id matches that of an earlier,
         # not-fully-spent transaction in the same chain. To test, make identical coinbases;
-        # the second one should be rejected.
+        # the second one should be rejected. See also CVE-2012-1909.
         #
         self.log.info("Reject a block with a transaction with a duplicate hash of a previous transaction (BIP30)")
         self.move_tip(60)

test/functional/mempool_accept.py

@@ -211,6 +211,7 @@ def run_test(self):
             rawtxs=[tx.serialize().hex()],
         )
 
+        # The following two validations prevent overflow of the output amounts (see CVE-2010-5139).
         self.log.info('A transaction with too large output value')
         tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
         tx.vout[0].nValue = 21000000 * COIN + 1

test/functional/p2p_invalid_block.py

@@ -53,10 +53,11 @@ def run_test(self):
         block_time = best_block["time"] + 1
 
         # Use merkle-root malleability to generate an invalid block with
-        # same blockheader.
+        # same blockheader (CVE-2012-2459).
         # Manufacture a block with 3 transactions (coinbase, spend of prior
         # coinbase, spend of that spend).  Duplicate the 3rd transaction to
         # leave merkle root and blockheader unchanged but invalidate the block.
+        # For more information on merkle-root malleability see src/consensus/merkle.cpp.
         self.log.info("Test merkle root malleability.")
 
         block2 = create_block(tip, create_coinbase(height), block_time)
@@ -81,15 +82,16 @@ def run_test(self):
 
         node.p2p.send_blocks_and_test([block2], node, success=False, reject_reason='bad-txns-duplicate')
 
-        # Check transactions for duplicate inputs
+        # Check transactions for duplicate inputs (CVE-2018-17144)
         self.log.info("Test duplicate input block.")
 
-        block2_orig.vtx[2].vin.append(block2_orig.vtx[2].vin[0])
-        block2_orig.vtx[2].rehash()
-        block2_orig.hashMerkleRoot = block2_orig.calc_merkle_root()
-        block2_orig.rehash()
-        block2_orig.solve()
-        node.p2p.send_blocks_and_test([block2_orig], node, success=False, reject_reason='bad-txns-inputs-duplicate')
+        block2_dup = copy.deepcopy(block2_orig)
+        block2_dup.vtx[2].vin.append(block2_dup.vtx[2].vin[0])
+        block2_dup.vtx[2].rehash()
+        block2_dup.hashMerkleRoot = block2_dup.calc_merkle_root()
+        block2_dup.rehash()
+        block2_dup.solve()
+        node.p2p.send_blocks_and_test([block2_dup], node, success=False, reject_reason='bad-txns-inputs-duplicate')
 
         self.log.info("Test very broken block.")
 
@@ -105,5 +107,31 @@ def run_test(self):
         node.p2p.send_blocks_and_test([block3], node, success=False, reject_reason='bad-cb-amount')
 
 
+        # Complete testing of CVE-2012-2459 by sending the original block.
+        # It should be accepted even though it has the same hash as the mutated one.
+
+        self.log.info("Test accepting original block after rejecting its mutated version.")
+        node.p2p.send_blocks_and_test([block2_orig], node, success=True, timeout=5)
+
+        # Update tip info
+        height += 1
+        block_time += 1
+        tip = int(block2_orig.hash, 16)
+
+        # Complete testing of CVE-2018-17144, by checking for the inflation bug.
+        # Create a block that spends the output of a tx in a previous block.
+        block4 = create_block(tip, create_coinbase(height), block_time)
+        tx3 = create_tx_with_script(tx2, 0, script_sig=b'\x51', amount=50 * COIN)
+
+        # Duplicates input
+        tx3.vin.append(tx3.vin[0])
+        tx3.rehash()
+        block4.vtx.append(tx3)
+        block4.hashMerkleRoot = block4.calc_merkle_root()
+        block4.rehash()
+        block4.solve()
+        self.log.info("Test inflation by duplicating input")
+        node.p2p.send_blocks_and_test([block4], node, success=False,  reject_reason='bad-txns-inputs-duplicate')
+
 if __name__ == '__main__':
     InvalidBlockRequestTest().main()