wallet: add shared ring database

This maps key images to rings, so that different forks can reuse
the rings by key image. This avoids revealing the real inputs like
would happen if two forks spent the same outputs with different
rings. This database is meant to be shared with all Monero forks
which don't bother making a new chain, putting users' privacy at
risk in the process. It is placed in a shared data directory by
default ($HOME/.shared-ringdb on UNIX like systems). You may
use --shared-ringdb-dir to override this location, and should
then do so for all Monero forks for them to share the database.

1 files changed, 16 insertions, 1 deletions

diff --git a/src/wallet/wallet2.h b/src/wallet/wallet2.h
index 2a883dce7..79686753b 100644
--- a/src/wallet/wallet2.h
+++ b/src/wallet/wallet2.h
@@ -810,6 +810,9 @@ namespace tools
       if(ver < 23)
         return;
       a & m_account_tags;
+      if(ver < 24)
+        return;
+      a & m_ring_history_saved;
     }
 
     /*!
@@ -1046,6 +1049,11 @@ namespace tools
       return epee::net_utils::invoke_http_json_rpc(uri, method_name, req, res, m_http_client, timeout, http_method, req_id);
     }
 
+    void set_ring_database(const std::string &filename);
+    const std::string get_ring_database() const { return m_ring_database; }
+    bool get_ring(const std::string &filename, const crypto::key_image &key_image, std::vector<uint64_t> &outs);
+    bool find_and_save_rings(const std::string &filename, bool force = true);
+
   private:
     /*!
      * \brief  Stores wallet information to wallet file.
@@ -1102,6 +1110,10 @@ namespace tools
     rct::multisig_kLRki get_multisig_kLRki(size_t n, const rct::key &k) const;
     rct::key get_multisig_k(size_t idx, const std::unordered_set<rct::key> &used_L) const;
     void update_multisig_rescan_info(const std::vector<std::vector<rct::key>> &multisig_k, const std::vector<std::vector<tools::wallet2::multisig_info>> &info, size_t n);
+    bool add_rings(const std::string &filename, const crypto::chacha_key &key, const cryptonote::transaction_prefix &tx);
+    bool add_rings(const std::string &filename, const cryptonote::transaction_prefix &tx);
+    bool remove_rings(const std::string &filename, const cryptonote::transaction_prefix &tx);
+    bool get_ring(const std::string &filename, const crypto::chacha_key &key, const crypto::key_image &key_image, std::vector<uint64_t> &outs);
 
     bool get_output_distribution(uint64_t &start_height, std::vector<uint64_t> &distribution);
 
@@ -1187,9 +1199,12 @@ namespace tools
     std::unordered_map<crypto::hash, address_tx> m_light_wallet_address_txs;
     // store calculated key image for faster lookup
     std::unordered_map<crypto::public_key, std::map<uint64_t, crypto::key_image> > m_key_image_cache;
+
+    std::string m_ring_database;
+    bool m_ring_history_saved;
   };
 }
-BOOST_CLASS_VERSION(tools::wallet2, 23)
+BOOST_CLASS_VERSION(tools::wallet2, 24)
 BOOST_CLASS_VERSION(tools::wallet2::transfer_details, 9)
 BOOST_CLASS_VERSION(tools::wallet2::multisig_info, 1)
 BOOST_CLASS_VERSION(tools::wallet2::multisig_info::LR, 0)