Dynamic Unlock from HF 16

src/cryptonote_config.h

@@ -40,7 +40,6 @@
 #define CRYPTONOTE_MAX_TX_SIZE                          1000000
 #define CRYPTONOTE_MAX_TX_PER_BLOCK                     0x10000000
 #define CRYPTONOTE_PUBLIC_ADDRESS_TEXTBLOB_VER          0
-#define CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW            60
 #define CURRENT_TRANSACTION_VERSION                     2
 #define CURRENT_BLOCK_MAJOR_VERSION                     7
 #define CURRENT_BLOCK_MINOR_VERSION                     7
@@ -185,6 +184,7 @@
 #define HF_VERSION_EXACT_COINBASE               16
 #define HF_VERSION_CLSAG                        16
 #define HF_VERSION_DETERMINISTIC_UNLOCK_TIME    16
+#define HF_VERSION_DYNAMIC_UNLOCK               16
 
 #define PER_KB_FEE_QUANTIZATION_DECIMALS        8
 

src/cryptonote_core/blockchain.cpp

@@ -1390,7 +1390,31 @@ bool Blockchain::prevalidate_miner_transaction(const block& b, uint64_t height,
     return false;
   }
   MDEBUG("Miner tx hash: " << get_transaction_hash(b.miner_tx));
-  CHECK_AND_ASSERT_MES(b.miner_tx.unlock_time == height + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW, false, "coinbase transaction transaction has the wrong unlock time=" << b.miner_tx.unlock_time << ", expected " << height + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW);
+
+  // Dynamic unlock time from HF 16
+  // To calculate unlock window, get the block hash at height-1337, convert the 
+  // first 3 characters from hexadecimal to decimal, multiply by 2, and then add 288.
+  // Unlock minimum 1 day (288 blocks), maximum is ~29 days ((4095*2)+288 = 8478 blocks)
+  // unlock time = unlock_window + height
+  if (hf_version >= HF_VERSION_DYNAMIC_UNLOCK)
+  {
+    crypto::hash blk_id = get_block_id_by_height(height-1337);
+    std::string hex_str = epee::string_tools::pod_to_hex(blk_id).substr(0, 3);
+    uint64_t blk_num = std::stol(hex_str,nullptr,16)*2;
+    uint64_t unlock_window = blk_num + 288;
+
+    if (b.miner_tx.unlock_time != height + unlock_window) {
+      MWARNING("Coinbase transaction has the wrong unlock time=" << b.miner_tx.unlock_time << ", expected " << height + unlock_window);
+      return false;
+    }
+    LOG_PRINT_L1("+++++ MINER TX UNLOCK TIME INFO" << 
+      "\nHeight: " << height << ", Unlock window: " << unlock_window << ", Unlock time: " << b.miner_tx.unlock_time << 
+      "\nblk_height: " << height-1337 << ", blk_id: " << blk_id << 
+      "\nhex_str: " << hex_str << ", blk_num: " << blk_num);
+  } else {
+    CHECK_AND_ASSERT_MES(b.miner_tx.unlock_time == height + 60, false, "coinbase transaction transaction has the wrong unlock time=" 
+      << b.miner_tx.unlock_time << ", expected " << height + 60);
+  }
 
   //check outs overflow
   //NOTE: not entirely sure this is necessary, given that this function is
@@ -1762,7 +1786,7 @@ bool Blockchain::create_block_template(block& b, const crypto::hash *from_block,
   //make blocks coin-base tx looks close to real coinbase tx to get truthful blob weight
   uint8_t hf_version = b.major_version;
   size_t max_outs = hf_version >= 4 ? 1 : 11;
-  bool r = construct_miner_tx(height, median_weight, already_generated_coins, txs_weight, fee, miner_address, b.miner_tx, ex_nonce, max_outs, hf_version);
+  bool r = construct_miner_tx(this, height, median_weight, already_generated_coins, txs_weight, fee, miner_address, b.miner_tx, ex_nonce, max_outs, hf_version);
   CHECK_AND_ASSERT_MES(r, false, "Failed to construct miner tx, first chance");
   size_t cumulative_weight = txs_weight + get_transaction_weight(b.miner_tx);
 #if defined(DEBUG_CREATE_BLOCK_TEMPLATE)
@@ -1771,7 +1795,7 @@ bool Blockchain::create_block_template(block& b, const crypto::hash *from_block,
 #endif
   for (size_t try_count = 0; try_count != 10; ++try_count)
   {
-    r = construct_miner_tx(height, median_weight, already_generated_coins, cumulative_weight, fee, miner_address, b.miner_tx, ex_nonce, max_outs, hf_version);
+    r = construct_miner_tx(this, height, median_weight, already_generated_coins, cumulative_weight, fee, miner_address, b.miner_tx, ex_nonce, max_outs, hf_version);
 
     CHECK_AND_ASSERT_MES(r, false, "Failed to construct miner tx, second chance");
     size_t coinbase_weight = get_transaction_weight(b.miner_tx);

src/cryptonote_core/cryptonote_tx_utils.cpp

@@ -76,7 +76,7 @@ namespace cryptonote
     LOG_PRINT_L2("destinations include " << num_stdaddresses << " standard addresses and " << num_subaddresses << " subaddresses");
   }
   //---------------------------------------------------------------
-  bool construct_miner_tx(size_t height, size_t median_weight, uint64_t already_generated_coins, size_t current_block_weight, uint64_t fee, const account_public_address &miner_address, transaction& tx, const blobdata& extra_nonce, size_t max_outs, uint8_t hard_fork_version) {
+  bool construct_miner_tx(const Blockchain *pb, size_t height, size_t median_weight, uint64_t already_generated_coins, size_t current_block_weight, uint64_t fee, const account_public_address &miner_address, transaction& tx, const blobdata& extra_nonce, size_t max_outs, uint8_t hard_fork_version) {
     tx.vin.clear();
     tx.vout.clear();
     tx.extra.clear();
@@ -167,7 +167,16 @@ namespace cryptonote
       tx.version = 1;
 
     //lock
-    tx.unlock_time = height + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW;
+    if (hard_fork_version >= HF_VERSION_DYNAMIC_UNLOCK)
+    {
+      crypto::hash blk_id = pb->get_block_id_by_height(height-1337);
+      std::string hex_str = epee::string_tools::pod_to_hex(blk_id).substr(0, 3);
+      uint64_t blk_num = std::stol(hex_str,nullptr,16)*2;
+      uint64_t unlock_window = blk_num + 288;
+      tx.unlock_time = height + unlock_window;
+    } else {
+      tx.unlock_time = height + 60;
+    }
     tx.vin.push_back(in);
 
     tx.invalidate_hashes();

src/cryptonote_core/cryptonote_tx_utils.h

@@ -37,7 +37,8 @@
 namespace cryptonote
 {
   //---------------------------------------------------------------
-  bool construct_miner_tx(size_t height, size_t median_weight, uint64_t already_generated_coins, size_t current_block_weight, uint64_t fee, const account_public_address &miner_address, transaction& tx, const blobdata& extra_nonce = blobdata(), size_t max_outs = 999, uint8_t hard_fork_version = 1);
+  class Blockchain;
+  bool construct_miner_tx(const Blockchain *pb, size_t height, size_t median_weight, uint64_t already_generated_coins, size_t current_block_weight, uint64_t fee, const account_public_address &miner_address, transaction& tx, const blobdata& extra_nonce = blobdata(), size_t max_outs = 999, uint8_t hard_fork_version = 1);
 
   struct tx_source_entry
   {

src/wallet/wallet2.cpp

@@ -8215,7 +8215,8 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
       const uint64_t amount = td.is_rct() ? 0 : td.amount();
       std::unordered_set<uint64_t> seen_indices;
       // request more for rct in base recent (locked) coinbases are picked, since they're locked for longer
-      size_t requested_outputs_count = base_requested_outputs_count + (td.is_rct() ? CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW - CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE : 0);
+      // Unlock minimum 1 day (288 blocks), maximum is ~29 days ((4095*2)+288 = 8478 blocks)
+      size_t requested_outputs_count = base_requested_outputs_count + (td.is_rct() ? 8478 - CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE : 0);
       size_t start = req.outputs.size();
       bool use_histogram = amount != 0 || !has_rct_distribution;
 
@@ -8531,7 +8532,8 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
     for(size_t idx: selected_transfers)
     {
       const transfer_details &td = m_transfers[idx];
-      size_t requested_outputs_count = base_requested_outputs_count + (td.is_rct() ? CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW - CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE : 0);
+      // Unlock minimum 1 day (288 blocks), maximum is ~29 days ((4095*2)+288 = 8478 blocks)
+      size_t requested_outputs_count = base_requested_outputs_count + (td.is_rct() ? 8478 - CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE : 0);
       outs.push_back(std::vector<get_outs_entry>());
       outs.back().reserve(fake_outputs_count + 1);
       const rct::key mask = td.is_rct() ? rct::commit(td.amount(), td.m_mask) : rct::zeroCommit(td.amount());