bch(g2): coinbase-author KAT + slice-d pool-serve hot path

.github/workflows/build.yml

@@ -343,6 +343,7 @@ jobs:
                     bch_genesis_conformance_test bch_abla_growth_soak_test \
                     bch_coinbase_kat_segwit_predicate_test \
                     bch_coinbase_kat_bytevector_test \
+                    bch_coinbase_author_kat_test \
                     bch_cashtokens_transparency_test \
                     bch_block_connector_test bch_block_ordering_test \
                     bch_utxo_connect_test bch_reorg_connect_test bch_reorg_rerequest_test \
@@ -436,6 +437,7 @@ jobs:
                     bch_genesis_conformance_test bch_abla_growth_soak_test \
                     bch_coinbase_kat_segwit_predicate_test \
                     bch_coinbase_kat_bytevector_test \
+                    bch_coinbase_author_kat_test \
                     bch_cashtokens_transparency_test \
                     bch_block_connector_test bch_block_ordering_test \
                     bch_utxo_connect_test bch_reorg_connect_test bch_reorg_rerequest_test \

scripts/gen_g2_oracle.py

@@ -0,0 +1,70 @@
+# Oracle golden generator for BCH G2 coinbase-author KAT.
+# Transcribes VERBATIM the v36 output-assembly from p2pool-merged-v36
+# p2pool/data.py:920-1085 (generate_transaction, v36_active branch):
+#   amounts = subsidy*weight//total_weight ;
+#   total_donation = subsidy - sum(amounts) ;
+#   if total_donation < 1 and subsidy>0: largest by (amount,script) -=1 ; recompute
+#   amounts[DON] += total_donation
+#   dests = sorted(scripts \ {DON}, key=(amounts[s], s))[-4000:]
+#   payouts = [{value:amounts[s], script:s} for s in dests if amounts[s]] + [DON last]
+import struct
+
+COMBINED_DONATION_SCRIPT = bytes.fromhex('a9148c6272621d89e8fa526dd86acff60c7136be8e8587')
+def p2pkh(b): return bytes.fromhex('76a914') + bytes([b])*20 + bytes.fromhex('88ac')
+A=p2pkh(0xaa); B=p2pkh(0xbb); C=p2pkh(0xcc); D=p2pkh(0xdd)
+
+def assemble_v36(weights, donation_weight, subsidy):
+    total_weight = sum(weights.values()) + donation_weight
+    amounts = dict((s, subsidy*w//total_weight) for s,w in weights.items())
+    total_donation = subsidy - sum(amounts.values())
+    if total_donation < 1 and subsidy > 0:
+        largest = max(amounts, key=lambda k:(amounts[k], k))
+        amounts[largest] -= 1
+        total_donation = subsidy - sum(amounts.values())
+    amounts[COMBINED_DONATION_SCRIPT] = amounts.get(COMBINED_DONATION_SCRIPT,0) + total_donation
+    excluded = {COMBINED_DONATION_SCRIPT}
+    dests = sorted([s for s in amounts if s not in excluded], key=lambda s:(amounts[s], s))[-4000:]
+    payouts = [(s, amounts[s]) for s in dests if amounts[s]]
+    payouts.append((COMBINED_DONATION_SCRIPT, amounts[COMBINED_DONATION_SCRIPT]))
+    return payouts
+
+def assemble_with_finderfee(weights, finder, donation_weight, subsidy):
+    # NEGATIVE control: pre-v36 math (199/200 haircut) + subsidy//200 finder fee.
+    total_weight = sum(weights.values()) + donation_weight
+    amounts = dict((s, subsidy*(199*w)//(200*total_weight)) for s,w in weights.items())
+    amounts[finder] = amounts.get(finder,0) + subsidy//200
+    total_donation = subsidy - sum(amounts.values())
+    if total_donation < 1 and subsidy > 0:
+        largest = max(amounts, key=lambda k:(amounts[k], k))
+        amounts[largest] -= 1
+        total_donation = subsidy - sum(amounts.values())
+    amounts[COMBINED_DONATION_SCRIPT] = amounts.get(COMBINED_DONATION_SCRIPT,0) + total_donation
+    dests = sorted([s for s in amounts if s != COMBINED_DONATION_SCRIPT], key=lambda s:(amounts[s], s))[-4000:]
+    payouts = [(s, amounts[s]) for s in dests if amounts[s]]
+    payouts.append((COMBINED_DONATION_SCRIPT, amounts[COMBINED_DONATION_SCRIPT]))
+    return payouts
+
+def varint(n):
+    if n < 0xfd: return bytes([n])
+    if n <= 0xffff: return b'\xfd'+struct.pack('<H',n)
+    if n <= 0xffffffff: return b'\xfe'+struct.pack('<I',n)
+    return b'\xff'+struct.pack('<Q',n)
+
+def serialize(payouts):
+    out = b''
+    for script, value in payouts:
+        out += struct.pack('<Q', value) + varint(len(script)) + script
+    return out
+
+SUB = 1_000_000_000
+cases = {
+ 'CASE1_ordering_tie': assemble_v36({A:10,B:20,C:20,D:50}, 0, SUB),
+ 'CASE2_donation_forced_last': assemble_v36({A:40,B:20}, 40, SUB),
+ 'CASE3_v36_no_finderfee': assemble_v36({A:60,B:40}, 0, SUB),
+ 'CASE3_NEG_with_finderfee': assemble_with_finderfee({A:60,B:40}, A, 0, SUB),
+}
+names = {A.hex():'A',B.hex():'B',C.hex():'C',D.hex():'D',COMBINED_DONATION_SCRIPT.hex():'DON'}
+for name, p in cases.items():
+    print('=== %s ===' % name)
+    for s,v in p: print('   %-4s value=%d' % (names.get(s.hex(),'?'), v))
+    print('   OUTSECTION_HEX=%s' % serialize(p).hex())

src/c2pool/main_bch.cpp

@@ -34,6 +34,8 @@
 #include <impl/bch/coin/regtest_block.hpp>
 #include <impl/bch/coin/rpc.hpp>
 #include <impl/bch/coin/node.hpp>
+#include <impl/bch/pool_entrypoint.hpp>
+#include <btclibs/util/strencodings.h>   // ParseHexBytes (sharechain prefix)
 
 #include <core/core_util.hpp>
 
@@ -71,7 +73,8 @@ void print_banner(const char* argv0)
         << "       " << argv0 << " --ibd [--testnet] [--near-tip] [--auto-kick] [--peer HOST:PORT] [--max-seconds N]\n"
         << "       " << argv0 << " --with-peer-verify [--testnet] [--peer HOST:PORT] [--max-seconds N]\n"
         << "       " << argv0 << " --leg-c-capture [--rpc-conf PATH]\n"
-        << "       " << argv0 << " --leg-c-capture-p2p [--rpc-conf PATH] [--p2p-port N]\n\n"
+        << "       " << argv0 << " --leg-c-capture-p2p [--rpc-conf PATH] [--p2p-port N]\n"
+        << "       " << argv0 << " --pool [--testnet|--regtest] [--stratum [HOST:]PORT] [--peer HOST:PORT] [--anchor N]\n\n"
         << "Status: M5 pool/sharechain + embedded-daemon assembly live.\n"
         << "        The embedded daemon (coin/embedded_daemon.hpp) is the primary\n"
         << "        work source; external BCHN-RPC stays as the fallback.\n"
@@ -583,6 +586,70 @@ int run_leg_c_capture_p2p(const std::string& conf_path, uint16_t p2p_port)
     return confirmed ? 0 : 1;
 }
 
+
+// --pool: PRODUCTION pool run-loop -- the first non-harness c2pool-bch
+// entrypoint. Stands up the BCH pool node + embedded coin daemon on one shared
+// io_context via bch::standup_pool_run, with the won-block sink bound (dual
+// path: embedded P2P primary + BCHN submitblock fallback) and, when --stratum
+// is given, the miner-facing BCHWorkSource + core::StratumServer listening so a
+// genuine share-author coinbase is what gets assembled and broadcast. The
+// --ibd path is a read-only evidence harness; THIS path is the real node.
+//
+// Config is built WITHOUT a YAML load (matches run_ibd): no pool.yaml/coin.yaml
+// is required for the slice. The two embedded-daemon wire fields (P2P magic +
+// BCHN peer) and the sharechain PREFIX (bucket-1 isolation primitive, never
+// standardized) are set by hand from BCH chainparams. The external BCHN-RPC
+// fallback inside EmbeddedDaemon::run() is retained (external_fallback law).
+//
+// p2pool-merged-v36 surface: NONE -- run-loop bring-up + block dispatch, not
+// share/PPLNS/coinbase/PoW bytes. PER-COIN ISOLATION: src/impl/bch only.
+int run_pool(const std::string& peer_host, uint16_t peer_port, bool testnet,
+             bool regtest, uint32_t anchor_height,
+             const std::string& stratum_addr, uint16_t stratum_port)
+{
+    boost::asio::io_context ioc;
+
+    bch::PoolConfig::is_testnet = testnet;
+
+    bch::Config config("bch");
+    // Skip Config::init() (no on-disk pool.yaml/coin.yaml); set only the fields
+    // the run-loop touches, from BCH chainparams.
+    config.coin()->m_testnet = testnet || regtest;
+    config.coin()->m_symbol  = "BCH";
+    config.coin()->m_p2p.address = NetService(peer_host, peer_port);
+    // BCH P2P network magic (pchMessageStart, BCHN chainparams.cpp): mainnet
+    // e3e1f3e8, testnet3 f4e5f3f4, regtest dab5bffa. Wrong magic == BCHN drops
+    // the peer with EOF right after connect.
+    config.coin()->m_p2p.prefix = regtest
+        ? std::vector<std::byte>{ std::byte{0xda}, std::byte{0xb5}, std::byte{0xbf}, std::byte{0xfa} }
+        : (testnet
+            ? std::vector<std::byte>{ std::byte{0xf4}, std::byte{0xe5}, std::byte{0xf3}, std::byte{0xf4} }
+            : std::vector<std::byte>{ std::byte{0xe3}, std::byte{0xe1}, std::byte{0xf3}, std::byte{0xe8} });
+    // Sharechain identity: BCH p2pool PREFIX namespaces the sharechain P2P
+    // framing. standup_pool_run's Node reads pool()->m_prefix.
+    config.pool()->m_prefix = ParseHexBytes(bch::PoolConfig::prefix_hex());
+
+    std::cout
+        << "[pool] c2pool-bch pool run-loop"
+        << (regtest ? " (regtest)" : (testnet ? " (testnet)" : " (mainnet)"))
+        << " -- BCHN peer " << peer_host << ":" << peer_port
+        << ", cold-start anchor=" << anchor_height;
+    if (stratum_port)
+        std::cout << ", stratum " << stratum_addr << ":" << stratum_port;
+    else
+        std::cout << ", stratum DISABLED (no --stratum)";
+    std::cout << "\n";
+
+    try {
+        bch::standup_pool_run(ioc, config, anchor_height,
+                              stratum_addr, stratum_port, testnet || regtest, regtest);
+    } catch (const std::exception& e) {
+        std::cout << "[pool] FATAL: " << e.what() << "\n";
+        return 1;
+    }
+    return 0;
+}
+
 } // namespace
 
 int main(int argc, char** argv)
@@ -592,6 +659,11 @@ int main(int argc, char** argv)
     bool want_leg_c = false;
     bool want_leg_c_p2p = false;
     bool want_with_peer_verify = false;
+    bool want_pool = false;
+    bool regtest = false;
+    std::string stratum_addr = "0.0.0.0";
+    uint16_t stratum_port = 0;        // 0 disables stratum; --stratum sets it
+    uint32_t anchor_height = 0;       // cold-start ABLA floor anchor
     uint16_t leg_c_p2p_port = 18444;  // BCHN regtest P2P default
     std::string rpc_conf;
     bool testnet = false;
@@ -609,6 +681,20 @@ int main(int argc, char** argv)
         if (std::strcmp(argv[i], "--help") == 0)     want_help = true;
         if (std::strcmp(argv[i], "--ibd") == 0)      want_ibd = true;
         if (std::strcmp(argv[i], "--with-peer-verify") == 0) want_with_peer_verify = true;
+        if (std::strcmp(argv[i], "--pool") == 0)     want_pool = true;
+        if (std::strcmp(argv[i], "--regtest") == 0)  { regtest = true; testnet = true; port = 18444; }
+        if (std::strcmp(argv[i], "--anchor") == 0 && i + 1 < argc)
+            anchor_height = static_cast<uint32_t>(std::stoul(argv[++i]));
+        if (std::strcmp(argv[i], "--stratum") == 0 && i + 1 < argc) {
+            std::string sp = argv[++i];
+            const auto c = sp.rfind(char(58));  // ASCII colon
+            if (c != std::string::npos) {
+                stratum_addr = sp.substr(0, c);
+                stratum_port = static_cast<uint16_t>(std::stoul(sp.substr(c + 1)));
+            } else {
+                stratum_port = static_cast<uint16_t>(std::stoul(sp));
+            }
+        }
         if (std::strcmp(argv[i], "--leg-c-capture") == 0) want_leg_c = true;
         if (std::strcmp(argv[i], "--leg-c-capture-p2p") == 0) want_leg_c_p2p = true;
         if (std::strcmp(argv[i], "--p2p-port") == 0 && i + 1 < argc)
@@ -651,6 +737,9 @@ int main(int argc, char** argv)
         return run_leg_c_capture(rpc_conf);
     }
 
+    if (want_pool)
+        return run_pool(host, port, testnet, regtest, anchor_height, stratum_addr, stratum_port);
+
     if (want_with_peer_verify)
         return run_with_peer_verify(host, port, testnet, max_seconds);
 

src/impl/bch/coin/asert.hpp

@@ -74,6 +74,31 @@ inline ASERTParams asert_testnet3() {
     };
 }
 
+inline uint256 bch_pow_limit_regtest() {
+    // BCH regtest powLimit (BCHN CRegTestParams). NOTE: top byte 0x7f does NOT
+    // satisfy CalculateASERT's 32-leading-zero-bits invariant -- which is why
+    // regtest runs with fPowNoRetargeting (ASERT is never invoked on regtest).
+    uint256 v;
+    v.SetHex("7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff");
+    return v;
+}
+
+/// BCH regtest difficulty params (BCHN CRegTestParams). fPowNoRetargeting=true,
+/// so the required target is fixed at the powLimit nBits (0x207fffff) for every
+/// block -- ASERT is bypassed (header_chain honours BCHChainParams::no_retargeting).
+/// The anchor here is nominal (genesis) and never feeds CalculateASERT.
+/// allow_min_difficulty mirrors BCHN regtest. (FINDING3: regtest must be its own
+/// net so --pool --regtest serves diff-1 0x207fffff, not the testnet anchor.)
+inline ASERTParams asert_regtest() {
+    return ASERTParams{
+        ASERTAnchor{0, 0x207fffff, 1296688602},  // genesis nBits/time (nominal)
+        2 * 24 * 60 * 60,
+        BCH_TARGET_SPACING,
+        true,
+        bch_pow_limit_regtest(),
+    };
+}
+
 inline ASERTParams asert_testnet4() {
     return ASERTParams{
         ASERTAnchor{16844, 0x1d00ffff, 1605451779},

src/impl/bch/coin/embedded_daemon.hpp

@@ -81,10 +81,12 @@ class EmbeddedDaemon {
     /// Cold-start ctor: floor-anchored ABLA at `anchor_height` (safe default
     /// when no VM300 BCHN pin is available yet). `context`/`config` outlive the
     /// daemon (owned by the binary entrypoint, same contract as coin::Node).
-    EmbeddedDaemon(auto* context, config_t* config, uint32_t anchor_height)
+    EmbeddedDaemon(auto* context, config_t* config, uint32_t anchor_height,
+                   bool is_regtest = false)
         : m_config(config),
-          m_chain(config->m_testnet ? BCHChainParams::testnet()
-                                    : BCHChainParams::mainnet()),
+          m_chain(is_regtest ? BCHChainParams::regtest()
+                             : (config->m_testnet ? BCHChainParams::testnet()
+                                                  : BCHChainParams::mainnet())),
           m_pool(),
           m_embedded(m_chain, m_pool, config->m_testnet),
           m_node(context, config),

src/impl/bch/coin/header_chain.hpp

@@ -150,6 +150,7 @@ struct BCHChainParams {
     uint256     pow_limit;                   // == asert.pow_limit (mirror for check_pow)
     uint256     genesis_hash;                // SHA256d genesis block hash (identification)
     bool        allow_min_difficulty{false}; // == asert.allow_min_difficulty (testnet)
+    bool        no_retargeting{false};       // == BCHN fPowNoRetargeting (regtest)
 
     // Fast-start checkpoint: skip syncing from genesis, start from a recent height.
     // The header chain seeds this checkpoint as if it were the genesis block.
@@ -196,6 +197,25 @@ struct BCHChainParams {
         p.fast_start_checkpoint = Checkpoint{0, p.genesis_hash};
         return p;
     }
+
+    /// BCH regtest params (P2P port 18444). BCHN CRegTestParams:
+    /// fPowNoRetargeting + fPowAllowMinDifficultyBlocks -- difficulty is fixed at
+    /// the genesis nBits 0x207fffff (powLimit), so a single CPU can mine it.
+    /// Genesis is the shared Satoshi regtest genesis. Seeds the cold-start tip so
+    /// served work nbits == 0x207fffff BEFORE the first P2P regtest block arrives
+    /// (FINDING3: --pool --regtest previously collapsed to testnet params and
+    /// served unwinnable testnet difficulty). GBT-from-local-regtest-BCHN
+    /// (regtest_block::build_from_gbt) is a deferred follow-on slice.
+    static BCHChainParams regtest() {
+        BCHChainParams p;
+        p.asert                = asert_regtest();
+        p.pow_limit            = p.asert.pow_limit;
+        p.allow_min_difficulty = p.asert.allow_min_difficulty;
+        p.no_retargeting       = true;
+        p.genesis_hash.SetHex("0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206");
+        p.fast_start_checkpoint = Checkpoint{0, p.genesis_hash};
+        return p;
+    }
 };
 
 // ─── PoW Functions ──────────────────────────────────────────────────────────
@@ -705,6 +725,14 @@ class HeaderChain {
     bool validate_difficulty(const BlockHeaderType& header, uint32_t new_height) {
         if (new_height < 2) return true; // genesis + first block
 
+        // Regtest (BCHN fPowNoRetargeting): difficulty never adjusts -- every
+        // block carries the powLimit nBits (0x207fffff). ASERT is bypassed here:
+        // CalculateASERT would assert on the regtest powLimit (top byte 0x7f
+        // violates its 32-leading-zero-bits invariant). The bits/target are
+        // already gated against pow_limit by check_pow at the accept site, so
+        // accept. (FINDING3.)
+        if (m_params.no_retargeting) return true;
+
         // Get tip (the block we're building on).
         auto prev_opt = lookup_header_internal(header.m_previous_block);
         if (!prev_opt) return false;