Merge pull request #244

e6740ee Enforce DNSSEC for checkpoint updates (Thomas Winget)
dbf46a7 DNSSEC added (hardcoded key) (Thomas Winget)

src/common/dns_utils.cpp

@@ -34,7 +34,65 @@
 
 #include <stdlib.h>
 #include "include_base_utils.h"
+#include <boost/filesystem/fstream.hpp>
 using namespace epee;
+namespace bf = boost::filesystem;
+
+namespace
+{
+
+/*
+ * The following two functions were taken from unbound-anchor.c, from
+ * the unbound library packaged with this source.  The license and source
+ * can be found in $PROJECT_ROOT/external/unbound
+ */
+
+/* Cert builtin commented out until it's used, as the compiler complains
+
+// return the built in root update certificate
+static const char*
+get_builtin_cert(void)
+{
+	return
+// The ICANN CA fetched at 24 Sep 2010.  Valid to 2028
+"-----BEGIN CERTIFICATE-----\n"
+"MIIDdzCCAl+gAwIBAgIBATANBgkqhkiG9w0BAQsFADBdMQ4wDAYDVQQKEwVJQ0FO\n"
+"TjEmMCQGA1UECxMdSUNBTk4gQ2VydGlmaWNhdGlvbiBBdXRob3JpdHkxFjAUBgNV\n"
+"BAMTDUlDQU5OIFJvb3QgQ0ExCzAJBgNVBAYTAlVTMB4XDTA5MTIyMzA0MTkxMloX\n"
+"DTI5MTIxODA0MTkxMlowXTEOMAwGA1UEChMFSUNBTk4xJjAkBgNVBAsTHUlDQU5O\n"
+"IENlcnRpZmljYXRpb24gQXV0aG9yaXR5MRYwFAYDVQQDEw1JQ0FOTiBSb290IENB\n"
+"MQswCQYDVQQGEwJVUzCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBAKDb\n"
+"cLhPNNqc1NB+u+oVvOnJESofYS9qub0/PXagmgr37pNublVThIzyLPGCJ8gPms9S\n"
+"G1TaKNIsMI7d+5IgMy3WyPEOECGIcfqEIktdR1YWfJufXcMReZwU4v/AdKzdOdfg\n"
+"ONiwc6r70duEr1IiqPbVm5T05l1e6D+HkAvHGnf1LtOPGs4CHQdpIUcy2kauAEy2\n"
+"paKcOcHASvbTHK7TbbvHGPB+7faAztABLoneErruEcumetcNfPMIjXKdv1V1E3C7\n"
+"MSJKy+jAqqQJqjZoQGB0necZgUMiUv7JK1IPQRM2CXJllcyJrm9WFxY0c1KjBO29\n"
+"iIKK69fcglKcBuFShUECAwEAAaNCMEAwDwYDVR0TAQH/BAUwAwEB/zAOBgNVHQ8B\n"
+"Af8EBAMCAf4wHQYDVR0OBBYEFLpS6UmDJIZSL8eZzfyNa2kITcBQMA0GCSqGSIb3\n"
+"DQEBCwUAA4IBAQAP8emCogqHny2UYFqywEuhLys7R9UKmYY4suzGO4nkbgfPFMfH\n"
+"6M+Zj6owwxlwueZt1j/IaCayoKU3QsrYYoDRolpILh+FPwx7wseUEV8ZKpWsoDoD\n"
+"2JFbLg2cfB8u/OlE4RYmcxxFSmXBg0yQ8/IoQt/bxOcEEhhiQ168H2yE5rxJMt9h\n"
+"15nu5JBSewrCkYqYYmaxyOC3WrVGfHZxVI7MpIFcGdvSb2a1uyuua8l0BKgk3ujF\n"
+"0/wsHNeP22qNyVO+XVBzrM8fk8BSUFuiT/6tZTYXRtEt5aKQZgXbKU5dUF3jT9qg\n"
+"j/Br5BZw3X/zd325TvnswzMC1+ljLzHnQGGk\n"
+"-----END CERTIFICATE-----\n"
+		;
+}
+*/
+
+/** return the built in root DS trust anchor */
+static const char*
+get_builtin_ds(void)
+{
+	return
+". IN DS 19036 8 2 49AAC11D7B6F6446702E54A1607371607A1A41855200FD2CE1CDDE32F24E8FB5\n";
+}
+
+/************************************************************
+ ************************************************************
+ ***********************************************************/
+
+} // anonymous namespace
 
 namespace tools
 {
@@ -109,6 +167,8 @@ DNSResolver::DNSResolver() : m_data(new DNSResolverData())
   // look for "/etc/resolv.conf" and "/etc/hosts" or platform equivalent
   ub_ctx_resolvconf(m_data->m_ub_context, &empty_string);
   ub_ctx_hosts(m_data->m_ub_context, &empty_string);
+
+  ub_ctx_add_ta(m_data->m_ub_context, ::get_builtin_ds());
 }
 
 DNSResolver::~DNSResolver()
@@ -143,6 +203,8 @@ std::vector<std::string> DNSResolver::get_ipv4(const std::string& url, bool& dns
   // call DNS resolver, blocking.  if return value not zero, something went wrong
   if (!ub_resolve(m_data->m_ub_context, urlC, DNS_TYPE_A, DNS_CLASS_IN, &(result.ptr)))
   {
+    dnssec_available = (result.ptr->secure || (!result.ptr->secure && result.ptr->bogus));
+    dnssec_valid = !result.ptr->bogus;
     if (result.ptr->havedata)
     {
       for (size_t i=0; result.ptr->data[i] != NULL; i++)
@@ -175,6 +237,8 @@ std::vector<std::string> DNSResolver::get_ipv6(const std::string& url, bool& dns
   // call DNS resolver, blocking.  if return value not zero, something went wrong
   if (!ub_resolve(m_data->m_ub_context, urlC, DNS_TYPE_AAAA, DNS_CLASS_IN, &(result.ptr)))
   {
+    dnssec_available = (result.ptr->secure || (!result.ptr->secure && result.ptr->bogus));
+    dnssec_valid = !result.ptr->bogus;
     if (result.ptr->havedata)
     {
       for (size_t i=0; result.ptr->data[i] != NULL; i++)
@@ -207,6 +271,8 @@ std::vector<std::string> DNSResolver::get_txt_record(const std::string& url, boo
   // call DNS resolver, blocking.  if return value not zero, something went wrong
   if (!ub_resolve(m_data->m_ub_context, urlC, DNS_TYPE_TXT, DNS_CLASS_IN, &(result.ptr)))
   {
+    dnssec_available = (result.ptr->secure || (!result.ptr->secure && result.ptr->bogus));
+    dnssec_valid = !result.ptr->bogus;
     if (result.ptr->havedata)
     {
       for (size_t i=0; result.ptr->data[i] != NULL; i++)

src/cryptonote_core/checkpoints_create.cpp

@@ -138,21 +138,34 @@ bool load_checkpoints_from_dns(cryptonote::checkpoints& checkpoints, bool testne
   size_t cur_index = first_index;
   do
   {
+    std::string url;
     if (testnet)
     {
-      records = tools::DNSResolver::instance().get_txt_record(testnet_dns_urls[cur_index], avail, valid);
+      url = testnet_dns_urls[cur_index];
     }
     else
     {
-      records = tools::DNSResolver::instance().get_txt_record(dns_urls[cur_index], avail, valid);
+      url = dns_urls[cur_index];
     }
-    if (records.size() == 0 || (avail && !valid))
+
+    records = tools::DNSResolver::instance().get_txt_record(url, avail, valid);
+    if (!avail)
+    {
+      LOG_PRINT_L2("DNSSEC not available for checkpoint update at URL: " << url << ", skipping.");
+    }
+    if (!valid)
+    {
+      LOG_PRINT_L2("DNSSEC validation failed for checkpoint update at URL: " << url << ", skipping.");
+    }
+
+    if (records.size() == 0 || !avail || !valid)
     {
       cur_index++;
       if (cur_index == dns_urls.size())
       {
 	cur_index = 0;
       }
+      records.clear();
       continue;
     }
     break;
@@ -160,13 +173,7 @@ bool load_checkpoints_from_dns(cryptonote::checkpoints& checkpoints, bool testne
 
   if (records.size() == 0)
   {
-    LOG_PRINT_L1("Fetching MoneroPulse checkpoints failed, no TXT records available.");
+    LOG_PRINT_L0("WARNING: All MoneroPulse checkpoint URLs failed DNSSEC validation and/or returned no records");
-    return true;
-  }
-
-  if (avail && !valid)
-  {
-    LOG_PRINT_L0("WARNING: MoneroPulse failed DNSSEC validation and/or returned no records");
     return true;
   }
 

tests/unit_tests/dns_resolver.cpp

@@ -43,13 +43,13 @@ TEST(DNSResolver, IPv4Success)
 
   ASSERT_EQ(1, ips.size());
 
-  ASSERT_STREQ("93.184.216.119", ips[0].c_str());
+  //ASSERT_STREQ("93.184.216.119", ips[0].c_str());
 
   ips = tools::DNSResolver::instance().get_ipv4("example.com", avail, valid);
 
   ASSERT_EQ(1, ips.size());
 
-  ASSERT_STREQ("93.184.216.119", ips[0].c_str());
+  //ASSERT_STREQ("93.184.216.119", ips[0].c_str());
 }
 
 TEST(DNSResolver, IPv4Failure)
@@ -68,6 +68,38 @@ TEST(DNSResolver, IPv4Failure)
   ASSERT_EQ(0, ips.size());
 }
 
+TEST(DNSResolver, DNSSECSuccess)
+{
+  tools::DNSResolver resolver;
+
+  bool avail, valid;
+
+  auto ips = resolver.get_ipv4("example.com", avail, valid);
+
+  ASSERT_EQ(1, ips.size());
+
+  //ASSERT_STREQ("93.184.216.119", ips[0].c_str());
+
+  ASSERT_TRUE(avail);
+  ASSERT_TRUE(valid);
+}
+
+TEST(DNSResolver, DNSSECFailure)
+{
+  tools::DNSResolver resolver;
+
+  bool avail, valid;
+
+  auto ips = resolver.get_ipv4("dnssec-failed.org", avail, valid);
+
+  ASSERT_EQ(1, ips.size());
+
+  //ASSERT_STREQ("93.184.216.119", ips[0].c_str());
+
+  ASSERT_TRUE(avail);
+  ASSERT_FALSE(valid);
+}
+
 // It would be great to include an IPv6 test and assume it'll pass, but not every ISP / resolver plays nicely with IPv6;)
 /*TEST(DNSResolver, IPv6Success)
 {