coinmarketscoin.txt

coinmarketscoin https://bitcointalk.org/index.php?topic=765082.0 (https://github.com/jyap808/coinmarketscoin)

Heritage: 

Problems:

Nothing obvious seen

Notes:

"Narration" (comments) is limited to 24 characters through RPC interface

This is a pretty dirty fork. I've not been able to find out what this is based off of, but it has many differences. Thus, this review might be less effective than usual

blockchain looks clean

+        const char* pszTimestamp = "September 1st, 2014 - TMZ: Celebrity Nude Photo Leak - The FBI Is on the Case!";

Does this actually work with compressed public keys?
 // ppcoin: sync-checkpoint master key
-const std::string CSyncCheckpoint::strMasterPubKey = "049F2C10997604217E7238A4C5CF2843570ADA001D1A247B228A7C5583ACD0F762A3130D0C4331EB262E3D0EB516AE6F7B0B1ADA43275013F8552A83A7C621B1D9";
+const std::string CSyncCheckpoint::strMasterPubKey = "02334512c0d7a9a69289c4b7ad1c76e5330ef9dacd9da912c91a853986bddf0434";

+    if (sNarr.length() > 24)
+        throw runtime_error("Narration must be 24 characters or less.");
+    

Appears to purposefully permit an easy way to store data in the blockchain:

         // Standard tx, sender provides pubkey, receiver adds signature
@@ -1306,6 +1303,11 @@ bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, vector<vector<unsi
 
         // Sender provides N pubkeys, receivers provides M signatures
         mTemplates.insert(make_pair(TX_MULTISIG, CScript() << OP_SMALLINTEGER << OP_PUBKEYS << OP_SMALLINTEGER << OP_CHECKMULTISIG));
+
+        // Empty, provably prunable, data-carrying output
+        mTemplates.insert(make_pair(TX_NULL_DATA, CScript() << OP_RETURN));
+        mTemplates.insert(make_pair(TX_NULL_DATA, CScript() << OP_RETURN << OP_SMALLDATA));
+        mTemplates.insert(make_pair(TX_NULL_DATA, CScript() << OP_RETURN << OP_SMALLDATA << OP_RETURN << OP_SMALLDATA));
     }
 
     // Shortcut for pay-to-script-hash, which are more constrained than the other types:
@@ -1390,6 +1392,12 @@ bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, vector<vector<unsi
                 else
                     break;
             }
+            else if (opcode2 == OP_SMALLDATA)
+            {
+                // small pushdata, <= MAX_OP_RETURN_RELAY bytes
+                if (vch1.size() > MAX_OP_RETURN_RELAY)
+                    break;
+            }

Watermarks: uint64_t