Merge pull request #749

bfd4a28 Update BlockchainDB documentation (Thomas Winget)
797357e Change Doxyfile, Blockchain not blockchain_storage (Thomas Winget)
c835215 remove defunct code from cryptonote::core (Thomas Winget)
50dba6d cryptonote::core doxygen documentation (Thomas Winget)
8ac329d doxygen documentation for difficulty functions (Thomas Winget)
540a76c Move checkpoint functions into checkpoints class (Thomas Winget)
1b0c98e doxygen documentation for checkpoints.{h,cpp} (Thomas Winget)
89c24ac Remove unnecessary or defunct code (Thomas Winget)
ab0ed14 doxygen include private and static members (Thomas Winget)
3a48449 Updated documentation for blockchain.* (Thomas Winget)

1 files changed, 240 insertions, 11 deletions

diff --git a/src/cryptonote_core/checkpoints.cpp b/src/cryptonote_core/checkpoints.cpp
index 24d066dae..c038a4802 100644
--- a/src/cryptonote_core/checkpoints.cpp
+++ b/src/cryptonote_core/checkpoints.cpp
@@ -1,21 +1,21 @@
 // Copyright (c) 2014-2016, 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
@@ -25,14 +25,44 @@
 // 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.
-// 
+//
 // Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
 
 #include "include_base_utils.h"
+
 using namespace epee;
 
 #include "checkpoints.h"
 
+#include "common/dns_utils.h"
+#include "include_base_utils.h"
+#include <sstream>
+#include <random>
+
+namespace
+{
+  bool dns_records_match(const std::vector<std::string>& a, const std::vector<std::string>& b)
+  {
+    if (a.size() != b.size()) return false;
+
+    for (const auto& record_in_a : a)
+    {
+      bool ok = false;
+      for (const auto& record_in_b : b)
+      {
+	if (record_in_a == record_in_b)
+	{
+	  ok = true;
+	  break;
+	}
+      }
+      if (!ok) return false;
+    }
+
+    return true;
+  }
+} // anonymous namespace
+
 namespace cryptonote
 {
   //---------------------------------------------------------------------------
@@ -84,10 +114,7 @@ namespace cryptonote
     return check_block(height, h, ignored);
   }
   //---------------------------------------------------------------------------
-  // this basically says if the blockchain is smaller than the first
-  // checkpoint then alternate blocks are allowed.  Alternatively, if the
-  // last checkpoint *before* the end of the current chain is also before
-  // the block to be added, then this is fine.
+  //FIXME: is this the desired behavior?
   bool checkpoints::is_alternative_block_allowed(uint64_t blockchain_height, uint64_t block_height) const
   {
     if (0 == block_height)
@@ -128,4 +155,206 @@ namespace cryptonote
     }
     return true;
   }
+
+  bool checkpoints::init_default_checkpoints()
+  {
+    ADD_CHECKPOINT(1,     "771fbcd656ec1464d3a02ead5e18644030007a0fc664c0a964d30922821a8148");
+    ADD_CHECKPOINT(10,    "c0e3b387e47042f72d8ccdca88071ff96bff1ac7cde09ae113dbb7ad3fe92381");
+    ADD_CHECKPOINT(100,   "ac3e11ca545e57c49fca2b4e8c48c03c23be047c43e471e1394528b1f9f80b2d");
+    ADD_CHECKPOINT(1000,  "5acfc45acffd2b2e7345caf42fa02308c5793f15ec33946e969e829f40b03876");
+    ADD_CHECKPOINT(10000, "c758b7c81f928be3295d45e230646de8b852ec96a821eac3fea4daf3fcac0ca2");
+    ADD_CHECKPOINT(22231, "7cb10e29d67e1c069e6e11b17d30b809724255fee2f6868dc14cfc6ed44dfb25");
+    ADD_CHECKPOINT(29556, "53c484a8ed91e4da621bb2fa88106dbde426fe90d7ef07b9c1e5127fb6f3a7f6");
+    ADD_CHECKPOINT(50000, "0fe8758ab06a8b9cb35b7328fd4f757af530a5d37759f9d3e421023231f7b31c");
+    ADD_CHECKPOINT(80000, "a62dcd7b536f22e003ebae8726e9e7276f63d594e264b6f0cd7aab27b66e75e3");
+    ADD_CHECKPOINT(202612, "bbd604d2ba11ba27935e006ed39c9bfdd99b76bf4a50654bc1e1e61217962698");
+    ADD_CHECKPOINT(202613, "e2aa337e78df1f98f462b3b1e560c6b914dec47b610698b7b7d1e3e86b6197c2");
+    ADD_CHECKPOINT(202614, "c29e3dc37d8da3e72e506e31a213a58771b24450144305bcba9e70fa4d6ea6fb");
+    ADD_CHECKPOINT(205000, "5d3d7a26e6dc7535e34f03def711daa8c263785f73ec1fadef8a45880fde8063");
+    ADD_CHECKPOINT(220000, "9613f455933c00e3e33ac315cc6b455ee8aa0c567163836858c2d9caff111553");
+    ADD_CHECKPOINT(230300, "bae7a80c46859db355556e3a9204a337ae8f24309926a1312323fdecf1920e61");
+    ADD_CHECKPOINT(230700, "93e631240ceac831da1aebfc5dac8f722c430463024763ebafa888796ceaeedf");
+    ADD_CHECKPOINT(231350, "b5add137199b820e1ea26640e5c3e121fd85faa86a1e39cf7e6cc097bdeb1131");
+    ADD_CHECKPOINT(232150, "955de8e6b6508af2c24f7334f97beeea651d78e9ade3ab18fec3763be3201aa8");
+    ADD_CHECKPOINT(249380, "654fb0a81ce3e5caf7e3264a70f447d4bd07586c08fa50f6638cc54da0a52b2d");
+    ADD_CHECKPOINT(460000, "75037a7aed3e765db96c75bcf908f59d690a5f3390baebb9edeafd336a1c4831");
+    ADD_CHECKPOINT(500000, "2428f0dbe49796be05ed81b347f53e1f7f44aed0abf641446ec2b94cae066b02");
+    ADD_CHECKPOINT(600000, "f5828ebf7d7d1cb61762c4dfe3ccf4ecab2e1aad23e8113668d981713b7a54c5");
+    ADD_CHECKPOINT(700000, "12be9b3d210b93f574d2526abb9c1ab2a881b479131fd0d4f7dac93875f503cd");
+    ADD_CHECKPOINT(825000, "56503f9ad766774b575be3aff73245e9d159be88132c93d1754764f28da2ff60");
+    ADD_CHECKPOINT(900000, "d9958d0e7dcf91a5a7b11de225927bf7efc6eb26240315ce12372be902cc1337");
+    ADD_CHECKPOINT(913193, "5292d5d56f6ba4de33a58d9a34d263e2cb3c6fee0aed2286fd4ac7f36d53c85f");
+
+    return true;
+  }
+
+  bool checkpoints::load_checkpoints_from_json(const std::string json_hashfile_fullpath)
+  {
+    boost::system::error_code errcode;
+    if (! (boost::filesystem::exists(json_hashfile_fullpath, errcode)))
+    {
+      LOG_PRINT_L1("Blockchain checkpoints file not found");
+      return true;
+    }
+
+    LOG_PRINT_L1("Adding checkpoints from blockchain hashfile");
+
+    uint64_t prev_max_height = get_max_height();
+    LOG_PRINT_L1("Hard-coded max checkpoint height is " << prev_max_height);
+    t_hash_json hashes;
+    epee::serialization::load_t_from_json_file(hashes, json_hashfile_fullpath);
+    for (std::vector<t_hashline>::const_iterator it = hashes.hashlines.begin(); it != hashes.hashlines.end(); )
+    {
+      uint64_t height;
+      height = it->height;
+      if (height <= prev_max_height) {
+	LOG_PRINT_L1("ignoring checkpoint height " << height);
+      } else {
+	std::string blockhash = it->hash;
+	LOG_PRINT_L1("Adding checkpoint height " << height << ", hash=" << blockhash);
+	ADD_CHECKPOINT(height, blockhash);
+      }
+      ++it;
+    }
+
+    return true;
+  }
+
+  bool checkpoints::load_checkpoints_from_dns(bool testnet)
+  {
+    // All four MoneroPulse domains have DNSSEC on and valid
+    static const std::vector<std::string> dns_urls = { "checkpoints.moneropulse.se"
+						     , "checkpoints.moneropulse.org"
+						     , "checkpoints.moneropulse.net"
+						     , "checkpoints.moneropulse.co"
+    };
+
+    static const std::vector<std::string> testnet_dns_urls = { "testpoints.moneropulse.se"
+							     , "testpoints.moneropulse.org"
+							     , "testpoints.moneropulse.net"
+							     , "testpoints.moneropulse.co"
+    };
+
+    std::vector<std::vector<std::string> > records;
+    records.resize(dns_urls.size());
+
+    std::random_device rd;
+    std::mt19937 gen(rd());
+    std::uniform_int_distribution<int> dis(0, dns_urls.size() - 1);
+    size_t first_index = dis(gen);
+
+    bool avail, valid;
+    size_t cur_index = first_index;
+    do
+    {
+      std::string url;
+      if (testnet)
+      {
+        url = testnet_dns_urls[cur_index];
+      }
+      else
+      {
+        url = dns_urls[cur_index];
+      }
+
+      records[cur_index] = tools::DNSResolver::instance().get_txt_record(url, avail, valid);
+      if (!avail)
+      {
+        records[cur_index].clear();
+        LOG_PRINT_L2("DNSSEC not available for checkpoint update at URL: " << url << ", skipping.");
+      }
+      if (!valid)
+      {
+        records[cur_index].clear();
+        LOG_PRINT_L2("DNSSEC validation failed for checkpoint update at URL: " << url << ", skipping.");
+      }
+
+      cur_index++;
+      if (cur_index == dns_urls.size())
+      {
+        cur_index = 0;
+      }
+      records[cur_index].clear();
+    } while (cur_index != first_index);
+
+    size_t num_valid_records = 0;
+
+    for( const auto& record_set : records)
+    {
+      if (record_set.size() != 0)
+      {
+        num_valid_records++;
+      }
+    }
+
+    if (num_valid_records < 2)
+    {
+      LOG_PRINT_L0("WARNING: no two valid MoneroPulse DNS checkpoint records were received");
+      return true;
+    }
+
+    int good_records_index = -1;
+    for (size_t i = 0; i < records.size() - 1; ++i)
+    {
+      if (records[i].size() == 0) continue;
+
+      for (size_t j = i + 1; j < records.size(); ++j)
+      {
+        if (dns_records_match(records[i], records[j]))
+        {
+    good_records_index = i;
+    break;
+        }
+      }
+      if (good_records_index >= 0) break;
+    }
+
+    if (good_records_index < 0)
+    {
+      LOG_PRINT_L0("WARNING: no two MoneroPulse DNS checkpoint records matched");
+      return true;
+    }
+
+    for (auto& record : records[good_records_index])
+    {
+      auto pos = record.find(":");
+      if (pos != std::string::npos)
+      {
+        uint64_t height;
+        crypto::hash hash;
+
+        // parse the first part as uint64_t,
+        // if this fails move on to the next record
+        std::stringstream ss(record.substr(0, pos));
+        if (!(ss >> height))
+        {
+    continue;
+        }
+
+        // parse the second part as crypto::hash,
+        // if this fails move on to the next record
+        std::string hashStr = record.substr(pos + 1);
+        if (!epee::string_tools::parse_tpod_from_hex_string(hashStr, hash))
+        {
+    continue;
+        }
+
+        ADD_CHECKPOINT(height, hashStr);
+      }
+    }
+    return true;
+  }
+
+  bool checkpoints::load_new_checkpoints(const std::string json_hashfile_fullpath, bool testnet, bool dns)
+  {
+    bool result;
+
+    result = load_checkpoints_from_json(json_hashfile_fullpath);
+    if (dns)
+    {
+      result &= load_checkpoints_from_dns(testnet);
+    }
+
+    return result;
+  }
 }