1 files changed, 340 insertions, 0 deletions
diff --git a/src/wallet/ringdb.cpp b/src/wallet/ringdb.cpp
new file mode 100644
index 000000000..5ea8c5fec
--- /dev/null
+++ b/src/wallet/ringdb.cpp
@@ -0,0 +1,340 @@
+// Copyright (c) 2018, The Monero Project
+// 
+// All rights reserved.
+// 
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+// 
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+// 
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+// 
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+// 
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// 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 <lmdb.h>
+#include <boost/algorithm/string.hpp>
+#include <boost/range/adaptor/transformed.hpp>
+#include <boost/filesystem.hpp>
+#include "misc_log_ex.h"
+#include "misc_language.h"
+#include "wallet_errors.h"
+#include "ringdb.h"
+
+#undef MONERO_DEFAULT_LOG_CATEGORY
+#define MONERO_DEFAULT_LOG_CATEGORY "wallet.ringdb"
+
+static int compare_hash32(const MDB_val *a, const MDB_val *b)
+{
+  uint32_t *va = (uint32_t*) a->mv_data;
+  uint32_t *vb = (uint32_t*) b->mv_data;
+  for (int n = 7; n >= 0; n--)
+  {
+    if (va[n] == vb[n])
+      continue;
+    return va[n] < vb[n] ? -1 : 1;
+  }
+
+  return 0;
+}
+
+static std::string compress_ring(const std::vector<uint64_t> &ring)
+{
+  std::string s;
+  for (uint64_t out: ring)
+    s += tools::get_varint_data(out);
+  return s;
+}
+
+static std::vector<uint64_t> decompress_ring(const std::string &s)
+{
+  std::vector<uint64_t> ring;
+  int read = 0;
+  for (std::string::const_iterator i = s.begin(); i != s.cend(); std::advance(i, read))
+  {
+    uint64_t out;
+    std::string tmp(i, s.cend());
+    read = tools::read_varint(tmp.begin(), tmp.end(), out);
+    THROW_WALLET_EXCEPTION_IF(read <= 0 || read > 256, tools::error::wallet_internal_error, "Internal error decompressing ring");
+    ring.push_back(out);
+  }
+  return ring;
+}
+
+std::string get_rings_filename(boost::filesystem::path filename)
+{
+  if (!boost::filesystem::is_directory(filename))
+    filename.remove_filename();
+  return filename.string();
+}
+
+static crypto::chacha_iv make_iv(const crypto::key_image &key_image, const crypto::chacha_key &key)
+{
+  static const char salt[] = "ringdsb";
+
+  uint8_t buffer[sizeof(key_image) + sizeof(key) + sizeof(salt)];
+  memcpy(buffer, &key_image, sizeof(key_image));
+  memcpy(buffer + sizeof(key_image), &key, sizeof(key));
+  memcpy(buffer + sizeof(key_image) + sizeof(key), salt, sizeof(salt));
+  crypto::hash hash;
+  crypto::cn_fast_hash(buffer, sizeof(buffer), hash.data);
+  static_assert(sizeof(hash) >= CHACHA_IV_SIZE, "Incompatible hash and chacha IV sizes");
+  crypto::chacha_iv iv;
+  memcpy(&iv, &hash, CHACHA_IV_SIZE);
+  return iv;
+}
+
+static std::string encrypt(const std::string &plaintext, const crypto::key_image &key_image, const crypto::chacha_key &key)
+{
+  const crypto::chacha_iv iv = make_iv(key_image, key);
+  std::string ciphertext;
+  ciphertext.resize(plaintext.size() + sizeof(iv));
+  crypto::chacha20(plaintext.data(), plaintext.size(), key, iv, &ciphertext[sizeof(iv)]);
+  memcpy(&ciphertext[0], &iv, sizeof(iv));
+  return ciphertext;
+}
+
+static std::string encrypt(const crypto::key_image &key_image, const crypto::chacha_key &key)
+{
+  return encrypt(std::string((const char*)&key_image, sizeof(key_image)), key_image, key);
+}
+
+static std::string decrypt(const std::string &ciphertext, const crypto::key_image &key_image, const crypto::chacha_key &key)
+{
+  const crypto::chacha_iv iv = make_iv(key_image, key);
+  std::string plaintext;
+  THROW_WALLET_EXCEPTION_IF(ciphertext.size() < sizeof(iv), tools::error::wallet_internal_error, "Bad ciphertext text");
+  plaintext.resize(ciphertext.size() - sizeof(iv));
+  crypto::chacha20(ciphertext.data() + sizeof(iv), ciphertext.size() - sizeof(iv), key, iv, &plaintext[0]);
+  return plaintext;
+}
+
+static int resize_env(MDB_env *env, const char *db_path, size_t n_entries)
+{
+  MDB_envinfo mei;
+  MDB_stat mst;
+  int ret;
+
+  ret = mdb_env_info(env, &mei);
+  if (ret)
+    return ret;
+  ret = mdb_env_stat(env, &mst);
+  if (ret)
+    return ret;
+  uint64_t size_used = mst.ms_psize * mei.me_last_pgno;
+  const size_t needed = n_entries * (32 + 1024); // highball 1kB for the ring data to make sure
+  uint64_t mapsize = mei.me_mapsize;
+  if (size_used + needed > mei.me_mapsize)
+  {
+    try
+    {
+      boost::filesystem::path path(db_path);
+      boost::filesystem::space_info si = boost::filesystem::space(path);
+      if(si.available < needed)
+      {
+        MERROR("!! WARNING: Insufficient free space to extend database !!: " << (si.available >> 20L) << " MB available");
+        return ENOSPC;
+      }
+    }
+    catch(...)
+    {
+      // print something but proceed.
+      MWARNING("Unable to query free disk space.");
+    }
+
+    mapsize += needed;
+  }
+  return mdb_env_set_mapsize(env, mapsize);
+}
+
+namespace tools { namespace ringdb
+{
+
+bool add_rings(const std::string &filename, const crypto::chacha_key &chacha_key, const cryptonote::transaction_prefix &tx)
+{
+  MDB_env *env;
+  MDB_dbi dbi;
+  MDB_txn *txn;
+  int dbr;
+  bool tx_active = false;
+
+  if (filename.empty())
+    return true;
+  tools::create_directories_if_necessary(filename);
+
+  dbr = mdb_env_create(&env);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to create LDMB environment: " + std::string(mdb_strerror(dbr)));
+  dbr = mdb_env_set_maxdbs(env, 1);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to set max env dbs: " + std::string(mdb_strerror(dbr)));
+  dbr = mdb_env_open(env, get_rings_filename(filename).c_str(), 0, 0664);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to open rings database file: " + std::string(mdb_strerror(dbr)));
+  epee::misc_utils::auto_scope_leave_caller env_dtor = epee::misc_utils::create_scope_leave_handler([&](){mdb_env_close(env);});
+  dbr = resize_env(env, filename.c_str(), tx.vin.size());
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to set env map size: " + std::string(mdb_strerror(dbr)));
+  dbr = mdb_txn_begin(env, NULL, 0, &txn);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to create LMDB transaction: " + std::string(mdb_strerror(dbr)));
+  epee::misc_utils::auto_scope_leave_caller txn_dtor = epee::misc_utils::create_scope_leave_handler([&](){if (tx_active) mdb_txn_abort(txn);});
+  tx_active = true;
+  dbr = mdb_dbi_open(txn, "rings", MDB_CREATE, &dbi);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to open LMDB dbi: " + std::string(mdb_strerror(dbr)));
+  epee::misc_utils::auto_scope_leave_caller dbi_dtor = epee::misc_utils::create_scope_leave_handler([&](){mdb_dbi_close(env, dbi);});
+  mdb_set_compare(txn, dbi, compare_hash32);
+
+  for (const auto &in: tx.vin)
+  {
+    if (in.type() != typeid(cryptonote::txin_to_key))
+      continue;
+    const auto &txin = boost::get<cryptonote::txin_to_key>(in);
+    const uint32_t ring_size = txin.key_offsets.size();
+    if (ring_size == 1)
+      continue;
+
+    MDB_val key, data;
+    std::string key_ciphertext = encrypt(txin.k_image, chacha_key);
+    key.mv_data = (void*)key_ciphertext.data();
+    key.mv_size = key_ciphertext.size();
+    MDEBUG("Saving relative ring for key image " << txin.k_image << ": " <<
+        boost::join(txin.key_offsets | boost::adaptors::transformed([](uint64_t out){return std::to_string(out);}), " "));
+    std::string compressed_ring = compress_ring(txin.key_offsets);
+    std::string data_ciphertext = encrypt(compressed_ring, txin.k_image, chacha_key);
+    data.mv_size = data_ciphertext.size();
+    data.mv_data = (void*)data_ciphertext.c_str();
+    dbr = mdb_put(txn, dbi, &key, &data, 0);
+    THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to add ring to database: " + std::string(mdb_strerror(dbr)));
+  }
+
+  dbr = mdb_txn_commit(txn);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to commit txn adding ring to database: " + std::string(mdb_strerror(dbr)));
+  tx_active = false;
+  return true;
+}
+
+bool remove_rings(const std::string &filename, const crypto::chacha_key &chacha_key, const cryptonote::transaction_prefix &tx)
+{
+  MDB_env *env;
+  MDB_dbi dbi;
+  MDB_txn *txn;
+  int dbr;
+  bool tx_active = false;
+
+  if (filename.empty())
+    return true;
+  tools::create_directories_if_necessary(filename);
+
+  dbr = mdb_env_create(&env);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to create LDMB environment: " + std::string(mdb_strerror(dbr)));
+  dbr = mdb_env_set_maxdbs(env, 1);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to set max env dbs: " + std::string(mdb_strerror(dbr)));
+  dbr = mdb_env_open(env, get_rings_filename(filename).c_str(), 0, 0664);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to open rings database file: " + std::string(mdb_strerror(dbr)));
+  epee::misc_utils::auto_scope_leave_caller env_dtor = epee::misc_utils::create_scope_leave_handler([&](){mdb_env_close(env);});
+  dbr = resize_env(env, filename.c_str(), tx.vin.size());
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to set env map size: " + std::string(mdb_strerror(dbr)));
+  dbr = mdb_txn_begin(env, NULL, 0, &txn);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to create LMDB transaction: " + std::string(mdb_strerror(dbr)));
+  epee::misc_utils::auto_scope_leave_caller txn_dtor = epee::misc_utils::create_scope_leave_handler([&](){if (tx_active) mdb_txn_abort(txn);});
+  tx_active = true;
+  dbr = mdb_dbi_open(txn, "rings", MDB_CREATE, &dbi);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to open LMDB dbi: " + std::string(mdb_strerror(dbr)));
+  epee::misc_utils::auto_scope_leave_caller dbi_dtor = epee::misc_utils::create_scope_leave_handler([&](){mdb_dbi_close(env, dbi);});
+  mdb_set_compare(txn, dbi, compare_hash32);
+
+  for (const auto &in: tx.vin)
+  {
+    if (in.type() != typeid(cryptonote::txin_to_key))
+      continue;
+    const auto &txin = boost::get<cryptonote::txin_to_key>(in);
+    const uint32_t ring_size = txin.key_offsets.size();
+    if (ring_size == 1)
+      continue;
+
+    MDB_val key, data;
+    std::string key_ciphertext = encrypt(txin.k_image, chacha_key);
+    key.mv_data = (void*)key_ciphertext.data();
+    key.mv_size = key_ciphertext.size();
+
+    dbr = mdb_get(txn, dbi, &key, &data);
+    THROW_WALLET_EXCEPTION_IF(dbr && dbr != MDB_NOTFOUND, tools::error::wallet_internal_error, "Failed to look for key image in LMDB table: " + std::string(mdb_strerror(dbr)));
+    if (dbr == MDB_NOTFOUND)
+      continue;
+    THROW_WALLET_EXCEPTION_IF(data.mv_size <= 0, tools::error::wallet_internal_error, "Invalid ring data size");
+
+    MDEBUG("Removing ring data for key image " << txin.k_image);
+    dbr = mdb_del(txn, dbi, &key, NULL);
+    THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to remove ring to database: " + std::string(mdb_strerror(dbr)));
+  }
+
+  dbr = mdb_txn_commit(txn);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to commit txn removing ring to database: " + std::string(mdb_strerror(dbr)));
+  tx_active = false;
+  return true;
+}
+
+bool get_ring(const std::string &filename, const crypto::chacha_key &chacha_key, const crypto::key_image &key_image, std::vector<uint64_t> &outs)
+{
+  MDB_env *env;
+  MDB_dbi dbi;
+  MDB_txn *txn;
+  int dbr;
+  bool tx_active = false;
+
+  if (filename.empty())
+    return false;
+  tools::create_directories_if_necessary(filename);
+
+  dbr = mdb_env_create(&env);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to create LDMB environment: " + std::string(mdb_strerror(dbr)));
+  dbr = mdb_env_set_maxdbs(env, 1);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to set max env dbs: " + std::string(mdb_strerror(dbr)));
+  dbr = mdb_env_open(env, get_rings_filename(filename).c_str(), 0, 0664);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to open rings database file: " + std::string(mdb_strerror(dbr)));
+  epee::misc_utils::auto_scope_leave_caller env_dtor = epee::misc_utils::create_scope_leave_handler([&](){mdb_env_close(env);});
+  dbr = resize_env(env, filename.c_str(), 0);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to set env map size: " + std::string(mdb_strerror(dbr)));
+  dbr = mdb_txn_begin(env, NULL, 0, &txn);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to create LMDB transaction: " + std::string(mdb_strerror(dbr)));
+  epee::misc_utils::auto_scope_leave_caller txn_dtor = epee::misc_utils::create_scope_leave_handler([&](){if (tx_active) mdb_txn_abort(txn);});
+  tx_active = true;
+  dbr = mdb_dbi_open(txn, "rings", MDB_CREATE, &dbi);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to open LMDB dbi: " + std::string(mdb_strerror(dbr)));
+  epee::misc_utils::auto_scope_leave_caller dbi_dtor = epee::misc_utils::create_scope_leave_handler([&](){mdb_dbi_close(env, dbi);});
+  mdb_set_compare(txn, dbi, compare_hash32);
+
+  MDB_val key, data;
+  std::string key_ciphertext = encrypt(key_image, chacha_key);
+  key.mv_data = (void*)key_ciphertext.data();
+  key.mv_size = key_ciphertext.size();
+  dbr = mdb_get(txn, dbi, &key, &data);
+  THROW_WALLET_EXCEPTION_IF(dbr && dbr != MDB_NOTFOUND, tools::error::wallet_internal_error, "Failed to look for key image in LMDB table: " + std::string(mdb_strerror(dbr)));
+  if (dbr == MDB_NOTFOUND)
+    return false;
+  THROW_WALLET_EXCEPTION_IF(data.mv_size <= 0, tools::error::wallet_internal_error, "Invalid ring data size");
+
+  std::string data_plaintext = decrypt(std::string((const char*)data.mv_data, data.mv_size), key_image, chacha_key);
+  outs = decompress_ring(data_plaintext);
+  MDEBUG("Found ring for key image " << key_image << ":");
+  MDEBUG("Relative: " << boost::join(outs | boost::adaptors::transformed([](uint64_t out){return std::to_string(out);}), " "));
+  outs = cryptonote::relative_output_offsets_to_absolute(outs);
+  MDEBUG("Absolute: " << boost::join(outs | boost::adaptors::transformed([](uint64_t out){return std::to_string(out);}), " "));
+
+  dbr = mdb_txn_commit(txn);
+  THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to commit txn getting ring from database: " + std::string(mdb_strerror(dbr)));
+  tx_active = false;
+  return true;
+}
+
+}}