Added support for IPv6 addresses in DNS.

include/dns.h

@@ -42,6 +42,7 @@
 
 namespace Tins {
     class IPv4Address;
+    class IPv6Address;
     
     /**
      * \class DNS
@@ -240,6 +241,7 @@ namespace Tins {
         typedef std::list<Query> queries_type;
         typedef std::list<Resource> resources_type;
         typedef IPv4Address address_type;
+        typedef IPv6Address address_v6_type;
         
         /**
          * \brief Default constructor.
@@ -485,6 +487,18 @@ namespace Tins {
          */
         void add_answer(const std::string &name, 
           const DNSResourceRecord::info &info, address_type ip);
+          
+        /**
+         * \brief Add a query response.
+         * 
+         * \param name The resolved name.
+         * \param type The type of this answer.
+         * \param qclass The class of this answer.
+         * \param ttl The time-to-live of this answer.
+         * \param ip The ip address of the resolved name.
+         */
+        void add_answer(const std::string &name, 
+          const DNSResourceRecord::info &info, address_v6_type ip);
                         
         /**
          * \brief Add a query response.

include/ipv6_address.h

@@ -72,6 +72,15 @@ public:
      */
     IPv6Address(const std::string &addr);
     
+    /**
+     * \brief Constructor from a buffer.
+     * 
+     * The ptr parameter must be at least address_size bytes long.
+     * 
+     * \param ptr The buffer from which to construct this object.
+     */
+    IPv6Address(const_iterator ptr);
+    
     /**
      * \brief Retrieve the string representation of this address.
      * 

src/dns.cpp

@@ -34,6 +34,7 @@
 #include <memory>
 #include "dns.h"
 #include "ip_address.h"
+#include "ipv6_address.h"
 
 using std::string;
 using std::list;
@@ -166,6 +167,13 @@ void DNS::add_answer(const string &name, const DNSResourceRecord::info &info,
     dns.answers = Endian::host_to_be<uint16_t>(ans.size());
 }
 
+void DNS::add_answer(const string &name, const DNSResourceRecord::info &info, 
+  address_v6_type ip) 
+{
+    ans.push_back(make_record(name, info, ip.begin(), address_v6_type::address_size));
+    dns.answers = Endian::host_to_be<uint16_t>(ans.size());
+}
+
 void DNS::add_answer(const std::string &name, const DNSResourceRecord::info &info, 
   const std::string &dname) 
 {
@@ -433,14 +441,7 @@ void DNS::convert_resources(const ResourcesType &lst, std::list<Resource> &res)
             if(Endian::be_to_host(it->information().type) == DNS::AAAA) {
                 if(sz != 16)
                     throw std::runtime_error("Malformed IPv6 address");
-                std::ostringstream oss;
-                oss << std::hex;
-                for(size_t i = 0; i < 16; i += 2) {
-                    oss << (int)ptr[i] << (int)ptr[i+1];
-                    if(i != 14)
-                        oss << ':';
-                }
-                addr = oss.str();
+                addr = IPv6Address(ptr).to_string();
             }
             else
                 compose_name(ptr, sz, addr);

src/ipv6_address.cpp

@@ -41,6 +41,10 @@ namespace Tins {
         std::fill(address, address + address_size, 0);
     }
     
+    IPv6Address::IPv6Address(const_iterator ptr) {
+        std::copy(ptr, ptr + address_size, address);
+    }
+    
     IPv6Address::IPv6Address(const std::string &addr) {
         if(inet_pton(AF_INET6, addr.c_str(), address) == 0)
             throw malformed_address();

tests/src/dns.cpp

@@ -1,6 +1,7 @@
 #include <gtest/gtest.h>
 #include <iostream>
 #include "dns.h"
+#include "ipv6_address.h"
 #include "utils.h"
 
 using namespace Tins;
@@ -235,3 +236,19 @@ TEST_F(DNSTest, AnswersWithSameName) {
         EXPECT_EQ(it->query_class(), DNS::IN);
     }
 }
+
+TEST_F(DNSTest, AnswersV6) {
+    DNS dns;
+    dns.add_answer("www.example.com", DNS::make_info(DNS::AAAA, DNS::IN, 0x762), IPv6Address("f9a8:239::1:1"));
+    dns.add_answer("www.example.com", DNS::make_info(DNS::AAAA, DNS::IN, 0x762), IPv6Address("f9a8:239::1:1"));
+    ASSERT_EQ(dns.answers_count(), 2);
+    
+    DNS::resources_type resources = dns.answers();
+    for(DNS::resources_type::const_iterator it = resources.begin(); it != resources.end(); ++it) {
+        EXPECT_EQ(it->dname(), "www.example.com");
+        EXPECT_EQ(it->type(), DNS::AAAA);
+        EXPECT_EQ(it->ttl(), 0x762);
+        EXPECT_EQ(it->data(), "f9a8:239::1:1");
+        EXPECT_EQ(it->query_class(), DNS::IN);
+    }
+}