wallet: reroll fake outs selection on local tx_sanity_check failure

src/cryptonote_core/tx_sanity_check.cpp

@@ -28,7 +28,7 @@
 
 #include <stdint.h>
 #include <vector>
-#include "cryptonote_basic/cryptonote_basic_impl.h"
+#include "cryptonote_basic/cryptonote_basic.h"
 #include "cryptonote_basic/cryptonote_format_utils.h"
 #include "blockchain.h"
 #include "tx_sanity_check.h"
@@ -39,7 +39,7 @@
 namespace cryptonote
 {
 
-bool tx_sanity_check(Blockchain &blockchain, const cryptonote::blobdata &tx_blob)
+bool tx_sanity_check(const cryptonote::blobdata &tx_blob, uint64_t rct_outs_available)
 {
   cryptonote::transaction tx;
 
@@ -70,14 +70,18 @@ bool tx_sanity_check(Blockchain &blockchain, const cryptonote::blobdata &tx_blob
     n_indices += in_to_key.key_offsets.size();
   }
 
+  return tx_sanity_check(rct_indices, n_indices, rct_outs_available);
+}
+
+bool tx_sanity_check(const std::set<uint64_t> &rct_indices, size_t n_indices, uint64_t rct_outs_available)
+{
   if (n_indices <= 10)
   {
     MDEBUG("n_indices is only " << n_indices << ", not checking");
     return true;
   }
 
-  uint64_t n_available = blockchain.get_num_mature_outputs(0);
-  if (n_available < 10000)
+  if (rct_outs_available < 10000)
     return true;
 
   if (rct_indices.size() < n_indices * 8 / 10)
@@ -88,9 +92,9 @@ bool tx_sanity_check(Blockchain &blockchain, const cryptonote::blobdata &tx_blob
 
   std::vector<uint64_t> offsets(rct_indices.begin(), rct_indices.end());
   uint64_t median = epee::misc_utils::median(offsets);
-  if (median < n_available * 6 / 10)
+  if (median < rct_outs_available * 6 / 10)
   {
-    MERROR("median offset index is too low (median is " << median << " out of total " << n_available << "offsets). Transactions should contain a higher fraction of recent outputs.");
+    MERROR("median offset index is too low (median is " << median << " out of total " << rct_outs_available << "offsets). Transactions should contain a higher fraction of recent outputs.");
     return false;
   }
 

src/cryptonote_core/tx_sanity_check.h

@@ -26,11 +26,11 @@
 // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+#include <set>
 #include "cryptonote_basic/blobdatatype.h"
 
 namespace cryptonote
 {
-  class Blockchain;
-
-  bool tx_sanity_check(Blockchain &blockchain, const cryptonote::blobdata &tx_blob);
+  bool tx_sanity_check(const cryptonote::blobdata &tx_blob, uint64_t rct_outs_available);
+  bool tx_sanity_check(const std::set<uint64_t> &rct_indices, size_t n_indices, uint64_t rct_outs_available);
 }

src/rpc/core_rpc_server.cpp

@@ -1087,7 +1087,7 @@ namespace cryptonote
       return true;
     }
 
-    if (req.do_sanity_checks && !cryptonote::tx_sanity_check(m_core.get_blockchain_storage(), tx_blob))
+    if (req.do_sanity_checks && !cryptonote::tx_sanity_check(tx_blob, m_core.get_blockchain_storage().get_num_mature_outputs(0)))
     {
       res.status = "Failed";
       res.reason = "Sanity check failed";

src/wallet/wallet2.cpp

@@ -44,6 +44,7 @@
 using namespace epee;
 
 #include "cryptonote_config.h"
+#include "cryptonote_core/tx_sanity_check.h"
 #include "wallet_rpc_helpers.h"
 #include "wallet2.h"
 #include "cryptonote_basic/cryptonote_format_utils.h"
@@ -7733,7 +7734,49 @@ void wallet2::light_wallet_get_outs(std::vector<std::vector<tools::wallet2::get_
   }
 }
 
+std::pair<std::set<uint64_t>, size_t> outs_unique(const std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs)
+{
+  std::set<uint64_t> unique;
+  size_t total = 0;
+
+  for (const auto &it : outs)
+  {
+    for (const auto &out : it)
+    {
+      const uint64_t global_index = std::get<0>(out);
+      unique.insert(global_index);
+    }
+    total += it.size();
+  }
+
+  return std::make_pair(std::move(unique), total);
+}
+
 void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, const std::vector<size_t> &selected_transfers, size_t fake_outputs_count)
+{
+  std::vector<uint64_t> rct_offsets;
+  for (size_t attempts = 3; attempts > 0; --attempts)
+  {
+    get_outs(outs, selected_transfers, fake_outputs_count, rct_offsets);
+
+    const auto unique = outs_unique(outs);
+    if (tx_sanity_check(unique.first, unique.second, rct_offsets.empty() ? 0 : rct_offsets.back()))
+    {
+      return;
+    }
+
+    std::vector<crypto::key_image> key_images;
+    key_images.reserve(selected_transfers.size());
+    std::for_each(selected_transfers.begin(), selected_transfers.end(), [this, &key_images](size_t index) {
+      key_images.push_back(m_transfers[index].m_key_image);
+    });
+    unset_ring(key_images);
+  }
+
+  THROW_WALLET_EXCEPTION(error::wallet_internal_error, tr("Transaction sanity check failed"));
+}
+
+void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, const std::vector<size_t> &selected_transfers, size_t fake_outputs_count, std::vector<uint64_t> &rct_offsets)
 {
   LOG_PRINT_L2("fake_outputs_count: " << fake_outputs_count);
   outs.clear();
@@ -7755,7 +7798,6 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
 
     // if we have at least one rct out, get the distribution, or fall back to the previous system
     uint64_t rct_start_height;
-    std::vector<uint64_t> rct_offsets;
     bool has_rct = false;
     uint64_t max_rct_index = 0;
     for (size_t idx: selected_transfers)
@@ -7764,7 +7806,7 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
         has_rct = true;
         max_rct_index = std::max(max_rct_index, m_transfers[idx].m_global_output_index);
       }
-    const bool has_rct_distribution = has_rct && get_rct_distribution(rct_start_height, rct_offsets);
+    const bool has_rct_distribution = has_rct && (!rct_offsets.empty() || get_rct_distribution(rct_start_height, rct_offsets));
     if (has_rct_distribution)
     {
       // check we're clear enough of rct start, to avoid corner cases below

src/wallet/wallet2.h

@@ -1435,6 +1435,7 @@ private:
     bool is_spent(const transfer_details &td, bool strict = true) const;
     bool is_spent(size_t idx, bool strict = true) const;
     void get_outs(std::vector<std::vector<get_outs_entry>> &outs, const std::vector<size_t> &selected_transfers, size_t fake_outputs_count);
+    void get_outs(std::vector<std::vector<get_outs_entry>> &outs, const std::vector<size_t> &selected_transfers, size_t fake_outputs_count, std::vector<uint64_t> &rct_offsets);
     bool tx_add_fake_output(std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, uint64_t global_index, const crypto::public_key& tx_public_key, const rct::key& mask, uint64_t real_index, bool unlocked) const;
     bool should_pick_a_second_output(bool use_rct, size_t n_transfers, const std::vector<size_t> &unused_transfers_indices, const std::vector<size_t> &unused_dust_indices) const;
     std::vector<size_t> get_only_rct(const std::vector<size_t> &unused_dust_indices, const std::vector<size_t> &unused_transfers_indices) const;