filter-ordinals.patch

--- a/src/script/interpreter.cpp
+++ b/src/script/interpreter.cpp
@@ -504,6 +504,14 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript&
                     return set_error(serror, SCRIPT_ERR_MINIMALDATA);
                 }
                 stack.push_back(vchPushValue);
+                if ((flags & SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS) && opcode == OP_FALSE) {
+                    auto pc_tmp = pc;
+                    opcodetype next_opcode;
+                    valtype dummy_data;
+                    if (script.GetOp(pc_tmp, next_opcode, dummy_data) && next_opcode == OP_IF) {
+                        return set_error(serror, SCRIPT_ERR_DISCOURAGE_UPGRADABLE_NOPS);
+                    }
+                }
             } else if (fExec || (OP_IF <= opcode && opcode <= OP_ENDIF))
             switch (opcode)
             {

Hi guys -- I made a patch -- which is much larger but also adds -ordislow=1 , which delays relay of newly-arrived blocks if they contain known-ordinal txns. Basically the node refuses to relay the block -- doesn't even announce the cmpctblock to peers -- for a time (while it's the tip, basically) if it contains known-ordinal txns. The way it can decide this without actually evaluating the block is to rely on the fact that it contains txns it had previously rejected due to ordinals. It uses a rolling bloom filter to maintain a set of 1 million txids it has rejected in the past (with false positive probability 10^-7 , for total space use of ~12MB for the set).

In the process of still testing it, but it's here, as a patch against Core v26.0rc2.

PR (to my own repo, heh): cculianu/bitcoin#1
Actual branch: https://github.com/cculianu/bitcoin/tree/ordislow_26.0rc2

Patch in-action, with -debug=ordislow -debug=cmpctblock: