path: root/libtorrent-extended/dht_pex_static_map.patch

diff --git a/src/dht/dht_bucket.cc b/src/dht/dht_bucket.cc
index 04aa475..819f4aa 100644
--- a/src/dht/dht_bucket.cc
+++ b/src/dht/dht_bucket.cc
@@ -52,6 +52,8 @@ DhtBucket::DhtBucket(const HashString& begin, const HashString& end) :
   m_good(0),
   m_bad(0),
 
+  m_fullCacheLength(0),
+
   m_begin(begin),
   m_end(end) {
 
@@ -67,6 +69,8 @@ DhtBucket::add_node(DhtNode* n) {
     m_good++;
   else if (n->is_bad())
     m_bad++;
+
+  m_fullCacheLength = 0;
 }
 
 void
@@ -81,6 +85,8 @@ DhtBucket::remove_node(DhtNode* n) {
     m_good--;
   else if (n->is_bad())
     m_bad--;
+
+  m_fullCacheLength = 0;
 }
 
 void
@@ -92,9 +98,11 @@ DhtBucket::count() {
 // Called every 15 minutes for housekeeping.
 void
 DhtBucket::update() {
-  // For now we only update the counts after some nodes have become bad
-  // due to prolonged inactivity.
   count();
+
+  // In case adjacent buckets whose nodes we borrowed have changed,
+  // we force an update of the cache.
+  m_fullCacheLength = 0;
 }
 
 DhtBucket::iterator
@@ -188,4 +196,23 @@ DhtBucket::split(const HashString& id) {
   return other;
 }
 
+void
+DhtBucket::build_full_cache() {
+  DhtBucketChain chain(this);
+
+  char* pos = m_fullCache;
+  do {
+    for (const_iterator itr = chain.bucket()->begin(); itr != chain.bucket()->end() && pos < m_fullCache + sizeof(m_fullCache); ++itr) {
+      if (!(*itr)->is_bad()) {
+        pos = (*itr)->store_compact(pos);
+
+        if (pos > m_fullCache + sizeof(m_fullCache))
+          throw internal_error("DhtRouter::store_closest_nodes wrote past buffer end.");
+      }
+    }
+  } while (pos < m_fullCache + sizeof(m_fullCache) && chain.next() != NULL);
+
+  m_fullCacheLength = pos - m_fullCache;
+}
+
 }
diff --git a/src/dht/dht_bucket.h b/src/dht/dht_bucket.h
index 97622a3..bcdfd67 100644
--- a/src/dht/dht_bucket.h
+++ b/src/dht/dht_bucket.h
@@ -111,6 +111,10 @@ public:
   DhtBucket*          parent() const                          { return m_parent; }
   DhtBucket*          child() const                           { return m_child; }
 
+  // Return a full bucket's worth of compact node data. If this bucket is not
+  // full, it uses nodes from the child/parent buckets until we have enough.
+  SimpleString        full_bucket();
+
   // Called by the DhtNode on its bucket to update good/bad node counts.
   void                node_now_good(bool was_bad);
   void                node_now_bad(bool was_good);
@@ -118,6 +122,8 @@ public:
 private:
   void                count();
 
+  void                build_full_cache();
+
   DhtBucket*          m_parent;
   DhtBucket*          m_child;
   
@@ -126,11 +132,15 @@ private:
   unsigned int        m_good;
   unsigned int        m_bad;
 
+  size_t              m_fullCacheLength;
+
   // These are 40 bytes together, so might as well put them last.
   // m_end is const because it is used as key for the DhtRouter routing table
   // map, which would be inconsistent if m_end were changed carelessly.
   HashString          m_begin;
   const HashString    m_end;
+
+  char                m_fullCache[num_nodes * 26];
 };
 
 // Helper class to recursively follow a chain of buckets.  It first recurses
@@ -160,6 +170,13 @@ DhtBucket::node_now_bad(bool was_good) {
   m_bad++;
 }
 
+inline SimpleString
+DhtBucket::full_bucket() {
+  if (!m_fullCacheLength)
+    build_full_cache();
+  return SimpleString(m_fullCache, m_fullCacheLength);
+}
+
 inline const DhtBucket*
 DhtBucketChain::next() {
   // m_restart is clear when we're done recursing into the children and
diff --git a/src/dht/dht_router.cc b/src/dht/dht_router.cc
index b1c95c3..ff38b8c 100644
--- a/src/dht/dht_router.cc
+++ b/src/dht/dht_router.cc
@@ -329,24 +329,6 @@ DhtRouter::node_invalid(const HashString& id) {
   delete_node(m_nodes.find(&node->id()));
 }
 
-char*
-DhtRouter::store_closest_nodes(const HashString& id, char* buffer, char* bufferEnd) {
-  DhtBucketChain chain(find_bucket(id)->second);
-
-  do {
-    for (DhtBucket::const_iterator itr = chain.bucket()->begin(); itr != chain.bucket()->end() && buffer != bufferEnd; ++itr) {
-      if (!(*itr)->is_bad()) {
-        buffer = (*itr)->store_compact(buffer);
-
-        if (buffer > bufferEnd)
-          throw internal_error("DhtRouter::store_closest_nodes wrote past buffer end.");
-      }
-    }
-  } while (buffer != bufferEnd && chain.next() != NULL);
-
-  return buffer;
-}
-
 Object*
 DhtRouter::store_cache(Object* container) const {
   container->insert_key("self_id", str());
@@ -470,7 +452,7 @@ DhtRouter::receive_timeout() {
   for (DhtBucketList::const_iterator itr = m_routingTable.begin(); itr != m_routingTable.end(); ++itr) {
     itr->second->update();
 
-    if (!itr->second->is_full() || itr->second->age() > timeout_bucket_bootstrap)
+    if (!itr->second->is_full() || itr->second == bucket() || itr->second->age() > timeout_bucket_bootstrap)
       bootstrap_bucket(itr->second);
   }
 
@@ -505,15 +487,13 @@ DhtRouter::generate_token(const rak::socket_address* sa, int token, char buffer[
   return buffer;
 }
 
-std::string
-DhtRouter::make_token(const rak::socket_address* sa) {
-  char token[20];
-
-  return std::string(generate_token(sa, m_curToken, token), size_token);
+SimpleString
+DhtRouter::make_token(const rak::socket_address* sa, char* buffer) {
+  return SimpleString(generate_token(sa, m_curToken, buffer), size_token);
 }
 
 bool
-DhtRouter::token_valid(const std::string& token, const rak::socket_address* sa) {
+DhtRouter::token_valid(SimpleString token, const rak::socket_address* sa) {
   if (token.length() != size_token)
     return false;
 
@@ -521,12 +501,12 @@ DhtRouter::token_valid(const std::string& token, const rak::socket_address* sa)
   char reference[20];
 
   // First try current token.
-  if (std::memcmp(generate_token(sa, m_curToken, reference), token.c_str(), size_token) == 0)
+  if (token == SimpleString(generate_token(sa, m_curToken, reference), size_token))
     return true;
 
   // If token recently changed, some clients may be using the older one.
   // That way a token is valid for 15-30 minutes, instead of 0-15.
-  return std::memcmp(generate_token(sa, m_prevToken, reference), token.c_str(), size_token) == 0;
+  return token == SimpleString(generate_token(sa, m_prevToken, reference), size_token);
 }
 
 DhtNode*
diff --git a/src/dht/dht_router.h b/src/dht/dht_router.h
index f2b673f..816747f 100644
--- a/src/dht/dht_router.h
+++ b/src/dht/dht_router.h
@@ -115,14 +115,14 @@ public:
 
   // Store compact node information (26 bytes) for nodes closest to the
   // given ID in the given buffer, return new buffer end.
-  char*               store_closest_nodes(const HashString& id, char* buffer, char* bufferEnd);
+  SimpleString        get_closest_nodes(const HashString& id)  { return find_bucket(id)->second->full_bucket(); }
 
   // Store DHT cache in the given container.
   Object*             store_cache(Object* container) const;
 
   // Create and verify a token. Tokens are valid between 15-30 minutes from creation.
-  std::string         make_token(const rak::socket_address* sa);
-  bool                token_valid(const std::string& token, const rak::socket_address* sa);
+  SimpleString        make_token(const rak::socket_address* sa, char* buffer);
+  bool                token_valid(SimpleString token, const rak::socket_address* sa);
 
   DhtManager::statistics_type get_statistics() const;
   void                reset_statistics()                      { m_server.reset_statistics(); }
@@ -147,6 +147,8 @@ private:
   bool                add_node_to_bucket(DhtNode* node);
   void                delete_node(const DhtNodeList::accessor& itr);
 
+  void                store_closest_nodes(const HashString& id, DhtBucket* bucket);
+
   DhtBucketList::iterator split_bucket(const DhtBucketList::iterator& itr, DhtNode* node);
 
   void                bootstrap();
diff --git a/src/dht/dht_server.cc b/src/dht/dht_server.cc
index 1f2234b..256b92b 100644
--- a/src/dht/dht_server.cc
+++ b/src/dht/dht_server.cc
@@ -38,13 +38,14 @@
 #include "globals.h"
 
 #include <algorithm>
-#include <sstream>
+#include <cstdio>
 
 #include "torrent/exceptions.h"
 #include "torrent/connection_manager.h"
 #include "torrent/object.h"
 #include "torrent/object_stream.h"
 #include "torrent/poll.h"
+#include "torrent/static_map.h"
 #include "torrent/throttle.h"
 #include "tracker/tracker_dht.h"
 
@@ -63,6 +64,34 @@ const char* DhtServer::queries[] = {
   "announce_peer",
 };
 
+// List of all possible keys we need/support in a DHT message.
+// Unsupported keys we receive are dropped (ignored) while decoding.
+// See torrent/static_map.h for how this works.
+DhtMessage::mapping_type dht_key_names[DhtMessage::length] = {
+  { key_a_id,       "a::id" },
+  { key_a_infoHash, "a::info_hash" },
+  { key_a_port,     "a::port", },
+  { key_a_target,   "a::target" },
+  { key_a_token,    "a::token" },
+
+  { key_e_0,        "e[0]" },
+  { key_e_1,        "e[1]" },
+
+  { key_q,          "q" },
+
+  { key_r_id,       "r::id" },
+  { key_r_nodes,    "r::nodes" },
+  { key_r_token,    "r::token" },
+  { key_r_values,   "r::values[]" },
+
+  { key_t,          "t::" },
+  { key_v,          "v" },
+  { key_y,          "y" },
+};
+
+template<>
+const DhtMessage::key_map_init DhtMessage::base_type::keyMap(dht_key_names);
+
 // Error in DHT protocol, avoids std::string ctor from communication_error
 class dht_error : public network_error {
 public:
@@ -238,54 +267,51 @@ DhtServer::update() {
 }
 
 void
-DhtServer::process_query(const Object& transactionId, const HashString& id, const rak::socket_address* sa, Object& request) {
+DhtServer::process_query(const HashString& id, const rak::socket_address* sa, const DhtMessage& msg) {
   m_queriesReceived++;
   m_networkUp = true;
 
-  std::string& query = request.get_key_string("q");
-
-  Object& arg = request.get_key("a");
+  SimpleString query = msg[key_q].as_sstring();
 
   // Construct reply.
-  Object reply = Object::create_map();
+  DhtMessage reply;
 
   if (query == "find_node")
-    create_find_node_response(arg, reply);
+    create_find_node_response(msg, reply);
 
   else if (query == "get_peers")
-    create_get_peers_response(arg, sa, reply);
+    create_get_peers_response(msg, sa, reply);
 
   else if (query == "announce_peer")
-    create_announce_peer_response(arg, sa, reply);
+    create_announce_peer_response(msg, sa, reply);
 
   else if (query != "ping")
     throw dht_error(dht_error_bad_method, "Unknown query type.");
 
   m_router->node_queried(id, sa);
-  create_response(transactionId, sa, reply);
+  create_response(msg, sa, reply);
 }
 
 void
-DhtServer::create_find_node_response(const Object& arg, Object& reply) {
-  const std::string& target = arg.get_key_string("target");
+DhtServer::create_find_node_response(const DhtMessage& req, DhtMessage& reply) {
+  SimpleString target = req[key_a_target].as_sstring();
 
   if (target.length() < HashString::size_data)
     throw dht_error(dht_error_protocol, "target string too short");
 
-  char compact[sizeof(compact_node_info) * DhtBucket::num_nodes];
-  char* end = m_router->store_closest_nodes(*HashString::cast_from(target), compact, compact + sizeof(compact));
-
-  if (end == compact)
+  SimpleString nodes = m_router->get_closest_nodes(*HashString::cast_from(target));
+  if (nodes.empty())
     throw dht_error(dht_error_generic, "No nodes");
 
-  reply.insert_key("nodes", std::string(compact, end));
+  reply[key_r_nodes] = nodes;
 }
 
 void
-DhtServer::create_get_peers_response(const Object& arg, const rak::socket_address* sa, Object& reply) {
-  reply.insert_key("token", m_router->make_token(sa));
+DhtServer::create_get_peers_response(const DhtMessage& req, const rak::socket_address* sa, DhtMessage& reply) {
+  reply[key_r_token] = m_router->make_token(sa, reply.data_end);
+  reply.data_end += reply[key_r_token].as_sstring().length();
 
-  const std::string& info_hash_str = arg.get_key_string("info_hash");
+  SimpleString info_hash_str = req[key_a_infoHash].as_sstring();
 
   if (info_hash_str.length() < HashString::size_data)
     throw dht_error(dht_error_protocol, "info hash too short");
@@ -296,35 +322,34 @@ DhtServer::create_get_peers_response(const Object& arg, const rak::socket_addres
 
   // If we're not tracking or have no peers, send closest nodes.
   if (!tracker || tracker->empty()) {
-    char compact[sizeof(compact_node_info) * DhtBucket::num_nodes];
-    char* end = m_router->store_closest_nodes(*info_hash, compact, compact + sizeof(compact));
-
-    if (end == compact)
+    SimpleString nodes = m_router->get_closest_nodes(*info_hash);
+    if (nodes.empty())
       throw dht_error(dht_error_generic, "No peers nor nodes");
 
-    reply.insert_key("nodes", std::string(compact, end));
+    reply[key_r_nodes] = nodes;
 
   } else {
-    reply.insert_key("values", Object::create_list()).as_list().swap(tracker->get_peers().as_list());
+    reply[key_r_values] = tracker->get_peers();
   }
 }
 
 void
-DhtServer::create_announce_peer_response(const Object& arg, const rak::socket_address* sa, Object& reply) {
-  const std::string& info_hash = arg.get_key_string("info_hash");
+DhtServer::create_announce_peer_response(const DhtMessage& req, const rak::socket_address* sa, DhtMessage& reply) {
+  SimpleString info_hash = req[key_a_infoHash].as_sstring();
 
   if (info_hash.length() < HashString::size_data)
     throw dht_error(dht_error_protocol, "info hash too short");
 
-  if (!m_router->token_valid(arg.get_key_string("token"), sa))
+  if (!m_router->token_valid(req[key_a_token].as_sstring(), sa))
     throw dht_error(dht_error_protocol, "Token invalid.");
 
   DhtTracker* tracker = m_router->get_tracker(*HashString::cast_from(info_hash), true);
-  tracker->add_peer(sa->sa_inet()->address_n(), arg.get_key_value("port"));
+  tracker->add_peer(sa->sa_inet()->address_n(), req[key_a_port].as_value());
 }
 
 void
-DhtServer::process_response(int transactionId, const HashString& id, const rak::socket_address* sa, Object& request) {
+DhtServer::process_response(const HashString& id, const rak::socket_address* sa, const DhtMessage& response) {
+  int transactionId = (unsigned char)response[key_t].as_sstring()[2];
   transaction_itr itr = m_transactions.find(DhtTransaction::key(sa, transactionId));
 
   // Response to a transaction we don't have in our table. At this point it's
@@ -351,11 +376,9 @@ DhtServer::process_response(int transactionId, const HashString& id, const rak::
     if ((id != transaction->id() && transaction->id() != m_router->zero_id))
       return;
 
-    const Object& response = request.get_key("r");
-
     switch (transaction->type()) {
       case DhtTransaction::DHT_FIND_NODE:
-        parse_find_node_reply(transaction->as_find_node(), response.get_key_string("nodes"));
+        parse_find_node_reply(transaction->as_find_node(), response[key_r_nodes].as_sstring());
         break;
 
       case DhtTransaction::DHT_GET_PEERS:
@@ -381,7 +404,8 @@ DhtServer::process_response(int transactionId, const HashString& id, const rak::
 }
 
 void
-DhtServer::process_error(int transactionId, const rak::socket_address* sa, Object& request) {
+DhtServer::process_error(const rak::socket_address* sa, const DhtMessage& error) {
+  int transactionId = (unsigned char)error[key_t].as_sstring()[2];
   transaction_itr itr = m_transactions.find(DhtTransaction::key(sa, transactionId));
 
   if (itr == m_transactions.end())
@@ -399,7 +423,7 @@ DhtServer::process_error(int transactionId, const rak::socket_address* sa, Objec
 }
 
 void
-DhtServer::parse_find_node_reply(DhtTransactionSearch* transaction, const std::string& nodes) {
+DhtServer::parse_find_node_reply(DhtTransactionSearch* transaction, SimpleString nodes) {
   transaction->complete(true);
 
   if (sizeof(const compact_node_info) != 26)
@@ -421,16 +445,16 @@ DhtServer::parse_find_node_reply(DhtTransactionSearch* transaction, const std::s
 }
 
 void
-DhtServer::parse_get_peers_reply(DhtTransactionGetPeers* transaction, const Object& response) {
+DhtServer::parse_get_peers_reply(DhtTransactionGetPeers* transaction, const DhtMessage& response) {
   DhtAnnounce* announce = static_cast<DhtAnnounce*>(transaction->as_search()->search());
 
   transaction->complete(true);
 
-  if (response.has_key_list("values"))
-    announce->receive_peers(response.get_key("values"));
+  if (response[key_r_values].is_sstring())
+    announce->receive_peers(response[key_r_values].as_sstring());
 
-  if (response.has_key_string("token"))
-    add_transaction(new DhtTransactionAnnouncePeer(transaction->id(), transaction->address(), announce->target(), response.get_key_string("token")), packet_prio_low);
+  if (response[key_r_token].is_sstring())
+    add_transaction(new DhtTransactionAnnouncePeer(transaction->id(), transaction->address(), announce->target(), response[key_r_token].as_sstring()), packet_prio_low);
 
   announce->update_status();
 }
@@ -490,17 +514,19 @@ DhtServer::create_query(transaction_itr itr, int tID, const rak::socket_address*
   if (itr->second->id() == m_router->id())
     throw internal_error("DhtServer::create_query trying to send to itself.");
 
-  Object query = Object::create_map();
+  DhtMessage query;
 
-  DhtTransaction* transaction = itr->second;
-  char trans_id = tID;
-  query.insert_key("t", std::string(&trans_id, 1));
-  query.insert_key("y", "q");
-  query.insert_key("q", queries[transaction->type()]);
-  query.insert_key("v", PEER_VERSION);
+  // Transaction ID is a bencode string.
+  query[key_t] = SimpleString(query.data_end, 3);
+  *query.data_end++ = '1';
+  *query.data_end++ = ':';
+  *query.data_end++ = tID;
 
-  Object& q = query.insert_key("a", Object::create_map());
-  q.insert_key("id", m_router->str());
+  DhtTransaction* transaction = itr->second;
+  query[key_y] = SimpleString("q", 1);
+  query[key_q] = SimpleString(queries[transaction->type()]);
+  query[key_v] = SimpleString(PEER_VERSION, 4);
+  query[key_a_id] = m_router->s_str();
 
   switch (transaction->type()) {
     case DhtTransaction::DHT_PING:
@@ -508,17 +534,17 @@ DhtServer::create_query(transaction_itr itr, int tID, const rak::socket_address*
       break;
 
     case DhtTransaction::DHT_FIND_NODE:
-      q.insert_key("target", transaction->as_find_node()->search()->target().str());
+      query[key_a_target] = transaction->as_find_node()->search()->target().s_str();
       break;
 
     case DhtTransaction::DHT_GET_PEERS:
-      q.insert_key("info_hash", transaction->as_get_peers()->search()->target().str());
+      query[key_a_infoHash] = transaction->as_get_peers()->search()->target().s_str();
       break;
 
     case DhtTransaction::DHT_ANNOUNCE_PEER:
-      q.insert_key("info_hash", transaction->as_announce_peer()->info_hash().str());
-      q.insert_key("token", transaction->as_announce_peer()->token());
-      q.insert_key("port", manager->connection_manager()->listen_port());
+      query[key_a_infoHash] = transaction->as_announce_peer()->info_hash().s_str();
+      query[key_a_token] = transaction->as_announce_peer()->token();
+      query[key_a_port] = manager->connection_manager()->listen_port();
       break;
   }
 
@@ -530,31 +556,26 @@ DhtServer::create_query(transaction_itr itr, int tID, const rak::socket_address*
 }
 
 void
-DhtServer::create_response(const Object& transactionId, const rak::socket_address* sa, Object& r) {
-  Object reply = Object::create_map();
-  r.insert_key("id", m_router->str());
-
-  reply.insert_key("t", transactionId);
-  reply.insert_key("y", "r");
-  reply.insert_key("r", r);
-  reply.insert_key("v", PEER_VERSION);
+DhtServer::create_response(const DhtMessage& req, const rak::socket_address* sa, DhtMessage& reply) {
+  reply[key_r_id] = m_router->s_str();
+  reply[key_t] = req[key_t];
+  reply[key_y] = SimpleString("r", 1);
+  reply[key_v] = SimpleString(PEER_VERSION, 4);
 
   add_packet(new DhtTransactionPacket(sa, reply), packet_prio_reply);
 }
 
 void
-DhtServer::create_error(const Object* transactionId, const rak::socket_address* sa, int num, const std::string& msg) {
-  Object error = Object::create_map();
+DhtServer::create_error(const DhtMessage& req, const rak::socket_address* sa, int num, const char* msg) {
+  DhtMessage error;
 
-  if (transactionId != NULL)
-    error.insert_key("t", *transactionId);
+  if (req[key_t].is_sstring())
+    error[key_t] = req[key_t];
 
-  error.insert_key("y", "e");
-  error.insert_key("v", PEER_VERSION);
-
-  Object& e = error.insert_key("e", Object::create_list());
-  e.insert_back(num);
-  e.insert_back(msg);
+  error[key_y] = SimpleString("e", 1);
+  error[key_v] = SimpleString(PEER_VERSION, 4);
+  error[key_e_0] = num;
+  error[key_e_1] = SimpleString(msg);
 
   add_packet(new DhtTransactionPacket(sa, error), packet_prio_reply);
 }
@@ -656,15 +677,12 @@ DhtServer::clear_transactions() {
 void
 DhtServer::event_read() {
   uint32_t total = 0;
-  std::istringstream sstream;
-
-  sstream.imbue(std::locale::classic());
 
   while (true) {
     Object request;
     rak::socket_address sa;
     int type = '?';
-    const Object* transactionId = NULL;
+    DhtMessage message;
     const HashString* nodeId = NULL;
 
     try {
@@ -675,31 +693,32 @@ DhtServer::event_read() {
         break;
 
       total += read;
-      sstream.str(std::string(buffer, read));
-
-      sstream >> request;
 
       // If it's not a valid bencode dictionary at all, it's probably not a DHT
       // packet at all, so we don't throw an error to prevent bounce loops.
-      if (sstream.fail() || !request.is_map())
+      try {
+        staticMap_read_bencode(buffer, buffer + read, message);
+      } catch (bencode_error& e) {
         continue;
+      }
 
-      if (!request.has_key("t"))
+      if (!message[key_t].is_sstring())
         throw dht_error(dht_error_protocol, "No transaction ID");
 
-      transactionId = &request.get_key("t");
-
-      if (!request.has_key_string("y"))
+      if (!message[key_y].is_sstring())
         throw dht_error(dht_error_protocol, "No message type");
 
-      if (request.get_key_string("y").length() != 1)
+      if (message[key_y].as_sstring().length() != 1)
         throw dht_error(dht_error_bad_method, "Unsupported message type");
 
-      type = request.get_key_string("y")[0];
+      type = message[key_y].as_sstring()[0];
 
       // Queries and replies have node ID in different dictionaries.
       if (type == 'r' || type == 'q') {
-        const std::string& nodeIdStr = request.get_key(type == 'q' ? "a" : "r").get_key_string("id");
+        if (!message[type == 'q' ? key_a_id : key_r_id].is_sstring())
+          throw dht_error(dht_error_protocol, "Invalid `id' value");
+
+        SimpleString nodeIdStr = message[type == 'q' ? key_a_id : key_r_id].as_sstring();
 
         if (nodeIdStr.length() < HashString::size_data)
           throw dht_error(dht_error_protocol, "`id' value too short");
@@ -709,7 +728,8 @@ DhtServer::event_read() {
 
       // Sanity check the returned transaction ID.
       if ((type == 'r' || type == 'e') && 
-          (!transactionId->is_string() || transactionId->as_string().length() != 1))
+          (!message[key_t].is_sstring() || message[key_t].as_sstring().length() != 3
+           || message[key_t].as_sstring()[0] != '1' || message[key_t].as_sstring()[1] != ':'))
         throw dht_error(dht_error_protocol, "Invalid transaction ID type/length.");
 
       // Stupid broken implementations.
@@ -718,15 +738,15 @@ DhtServer::event_read() {
 
       switch (type) {
         case 'q':
-          process_query(*transactionId, *nodeId, &sa, request);
+          process_query(*nodeId, &sa, message);
           break;
 
         case 'r':
-          process_response(((unsigned char*)transactionId->as_string().c_str())[0], *nodeId, &sa, request);
+          process_response(*nodeId, &sa, message);
           break;
 
         case 'e':
-          process_error(((unsigned char*)transactionId->as_string().c_str())[0], &sa, request);
+          process_error(&sa, message);
           break;
 
         default:
@@ -737,16 +757,19 @@ DhtServer::event_read() {
     // so that if it repeatedly sends malformed replies we will drop it instead of propagating it
     // to other nodes.
     } catch (bencode_error& e) {
-      if ((type == 'r' || type == 'e') && nodeId != NULL)
+      if ((type == 'r' || type == 'e') && nodeId != NULL) {
         m_router->node_inactive(*nodeId, &sa);
-      else
-        create_error(transactionId, &sa, dht_error_protocol, std::string("Malformed packet: ") + e.what());
+      } else {
+        snprintf(message.data_end, message.data + message.data_size - message.data_end - 1, "Malformed packet: %s", e.what());
+        message.data[message.data_size - 1] = 0;
+        create_error(message, &sa, dht_error_protocol, message.data_end);
+      }
 
     } catch (dht_error& e) {
       if ((type == 'r' || type == 'e') && nodeId != NULL)
         m_router->node_inactive(*nodeId, &sa);
       else
-        create_error(transactionId, &sa, e.code(), e.what());
+        create_error(message, &sa, e.code(), e.what());
 
     } catch (network_error& e) {
 
diff --git a/src/dht/dht_server.h b/src/dht/dht_server.h
index 1855b73..1f55f15 100644
--- a/src/dht/dht_server.h
+++ b/src/dht/dht_server.h
@@ -46,6 +46,7 @@
 #include "net/throttle_node.h"
 #include "download/download_info.h"  // for SocketAddressCompact
 #include "torrent/hash_string.h"
+#include "torrent/simple_string.h"
 
 #include "dht_transaction.h"
 
@@ -56,6 +57,7 @@ class DhtNode;
 class DhtRouter;
 
 class DownloadInfo;
+class DhtMessage;
 class TrackerDht;
 
 // UDP server that handles the DHT node communications.
@@ -134,23 +136,23 @@ private:
 
   void                start_write();
 
-  void                process_query(const Object& transaction, const HashString& id, const rak::socket_address* sa, Object& req);
-  void                process_response(int transaction, const HashString& id, const rak::socket_address* sa, Object& req);
-  void                process_error(int transaction, const rak::socket_address* sa, Object& req);
+  void                process_query(const HashString& id, const rak::socket_address* sa, const DhtMessage& req);
+  void                process_response(const HashString& id, const rak::socket_address* sa, const DhtMessage& req);
+  void                process_error(const rak::socket_address* sa, const DhtMessage& error);
 
-  void                parse_find_node_reply(DhtTransactionSearch* t, const std::string& nodes);
-  void                parse_get_peers_reply(DhtTransactionGetPeers* t, const Object& res);
+  void                parse_find_node_reply(DhtTransactionSearch* t, SimpleString res);
+  void                parse_get_peers_reply(DhtTransactionGetPeers* t, const DhtMessage& res);
 
   void                find_node_next(DhtTransactionSearch* t);
 
   void                add_packet(DhtTransactionPacket* packet, int priority);
   void                create_query(transaction_itr itr, int tID, const rak::socket_address* sa, int priority);
-  void                create_response(const Object& transactionID, const rak::socket_address* sa, Object& r);
-  void                create_error(const Object* transactionID, const rak::socket_address* sa, int num, const std::string& msg);
+  void                create_response(const DhtMessage& req, const rak::socket_address* sa, DhtMessage& reply);
+  void                create_error(const DhtMessage& req, const rak::socket_address* sa, int num, const char* msg);
 
-  void                create_find_node_response(const Object& arg, Object& reply);
-  void                create_get_peers_response(const Object& arg, const rak::socket_address* sa, Object& reply);
-  void                create_announce_peer_response(const Object& arg, const rak::socket_address* sa, Object& reply);
+  void                create_find_node_response(const DhtMessage& arg, DhtMessage& reply);
+  void                create_get_peers_response(const DhtMessage& arg, const rak::socket_address* sa, DhtMessage& reply);
+  void                create_announce_peer_response(const DhtMessage& arg, const rak::socket_address* sa, DhtMessage& reply);
 
   int                 add_transaction(DhtTransaction* t, int priority);
 
diff --git a/src/dht/dht_tracker.cc b/src/dht/dht_tracker.cc
index 416dbf3..6e1afe9 100644
--- a/src/dht/dht_tracker.cc
+++ b/src/dht/dht_tracker.cc
@@ -54,8 +54,8 @@ DhtTracker::add_peer(uint32_t addr, uint16_t port) {
 
   // Check if peer exists. If not, find oldest peer.
   for (unsigned int i = 0; i < size(); i++) {
-    if (m_peers[i].addr == compact.addr) {
-      m_peers[i].port = compact.port;
+    if (m_peers[i].peer.addr == compact.addr) {
+      m_peers[i].peer.port = compact.port;
       m_lastSeen[i] = cachedTime.seconds();
       return;
 
@@ -77,10 +77,13 @@ DhtTracker::add_peer(uint32_t addr, uint16_t port) {
   }
 }
 
-// Return compact info (6 bytes) for up to 30 peers, returning different
-// peers for each call if there are more.
-Object
+// Return compact info as bencoded string (8 bytes per peer) for up to 30 peers,
+// returning different peers for each call if there are more.
+SimpleString
 DhtTracker::get_peers(unsigned int maxPeers) {
+  if (sizeof(BencodeAddress) != 8)
+    throw internal_error("DhtTracker::BencodeAddress is packed incorrectly.");
+
   PeerList::iterator first = m_peers.begin();
   PeerList::iterator last = m_peers.end();
 
@@ -94,11 +97,7 @@ DhtTracker::get_peers(unsigned int maxPeers) {
     last = first + maxPeers;
   }
 
-  Object peers = Object::create_list();
-  for (; first != last; ++first)
-    peers.insert_back(std::string(first->c_str(), sizeof(*first)));
-
-  return peers;
+  return SimpleString(first->bencode(), last->bencode() - first->bencode());
 }
 
 // Remove old announces.
@@ -107,9 +106,9 @@ DhtTracker::prune(uint32_t maxAge) {
   uint32_t minSeen = cachedTime.seconds() - maxAge;
 
   for (unsigned int i = 0; i < m_lastSeen.size(); i++)
-    if (m_lastSeen[i] < minSeen) m_peers[i].port = 0;
+    if (m_lastSeen[i] < minSeen) m_peers[i].peer.port = 0;
 
-  m_peers.erase(std::remove_if(m_peers.begin(), m_peers.end(), rak::on(rak::mem_ref(&SocketAddressCompact::port), std::bind2nd(std::equal_to<uint16_t>(), 0))), m_peers.end());
+  m_peers.erase(std::remove_if(m_peers.begin(), m_peers.end(), std::mem_fun_ref(&BencodeAddress::empty)), m_peers.end());
   m_lastSeen.erase(std::remove_if(m_lastSeen.begin(), m_lastSeen.end(), std::bind2nd(std::less<uint32_t>(), minSeen)), m_lastSeen.end());
 
   if (m_peers.size() != m_lastSeen.size())
diff --git a/src/dht/dht_tracker.h b/src/dht/dht_tracker.h
index 8515dd0..53fd1e3 100644
--- a/src/dht/dht_tracker.h
+++ b/src/dht/dht_tracker.h
@@ -43,6 +43,7 @@
 #include <rak/socket_address.h>
 
 #include "download/download_info.h"  // for SocketAddressCompact
+#include "torrent/simple_string.h"
 
 namespace torrent {
 
@@ -65,14 +66,26 @@ public:
   size_t              size() const                 { return m_peers.size(); }
 
   void                add_peer(uint32_t addr, uint16_t port);
-  Object              get_peers(unsigned int maxPeers = max_peers);
+  SimpleString        get_peers(unsigned int maxPeers = max_peers);
 
   // Remove old announces from the tracker that have not reannounced for
   // more than the given number of seconds.
   void                prune(uint32_t maxAge);
 
 private:
-  typedef std::vector<SocketAddressCompact> PeerList;
+  // We need to store the address as a bencoded string.
+  struct BencodeAddress {
+    char                 header[2];
+    SocketAddressCompact peer;
+
+    BencodeAddress(const SocketAddressCompact& p) : peer(p) { header[0] = '6'; header[1] = ':'; }
+
+    const char*  bencode() const { return header; }
+
+    bool         empty() const   { return !peer.port; }
+  } __attribute__ ((packed));
+
+  typedef std::vector<BencodeAddress> PeerList;
 
   PeerList               m_peers;
   std::vector<uint32_t>  m_lastSeen;
diff --git a/src/dht/dht_transaction.cc b/src/dht/dht_transaction.cc
index 2a6a8a6..0b3cfd0 100644
--- a/src/dht/dht_transaction.cc
+++ b/src/dht/dht_transaction.cc
@@ -123,7 +123,7 @@ DhtSearch::trim(bool final) {
   // We keep:
   // - the max_contacts=18 closest good or unknown nodes and all nodes closer
   //   than them (to see if further searches find closer ones)
-  // - for announces, also the 8 closest good nodes (i.e. nodes that have
+  // - for announces, also the 3 closest good nodes (i.e. nodes that have
   //   replied) to have at least that many for the actual announce
   // - any node that currently has transactions pending
   //
@@ -136,7 +136,7 @@ DhtSearch::trim(bool final) {
   // node is new and unknown otherwise
 
   int needClosest = final ? 0 : max_contacts;
-  int needGood = is_announce() ? DhtBucket::num_nodes : 0;
+  int needGood = is_announce() ? max_announce : 0;
 
   // We're done if we can't find any more nodes to contact.
   m_next = end();
@@ -252,7 +252,7 @@ DhtAnnounce::start_announce() {
 }
 
 void 
-DhtAnnounce::receive_peers(const Object& peers) {
+DhtAnnounce::receive_peers(SimpleString peers) {
   m_tracker->receive_peers(peers);
 }
 
@@ -262,9 +262,9 @@ DhtAnnounce::update_status() {
 }
 
 void
-DhtTransactionPacket::build_buffer(const Object& data) {
+DhtTransactionPacket::build_buffer(const DhtMessage& msg) {
   char buffer[1500];  // If the message would exceed an Ethernet frame, something went very wrong.
-  object_buffer_t result = object_write_bencode_c(object_write_to_buffer, NULL, std::make_pair(buffer, buffer + sizeof(buffer)), &data);
+  object_buffer_t result = staticMap_write_bencode_c(object_write_to_buffer, NULL, std::make_pair(buffer, buffer + sizeof(buffer)), msg);
 
   m_length = result.second - buffer;
   m_data = new char[m_length];
@@ -277,7 +277,6 @@ DhtTransaction::DhtTransaction(int quick_timeout, int timeout, const HashString&
     m_sa(*sa),
     m_timeout(cachedTime.seconds() + timeout),
     m_quickTimeout(cachedTime.seconds() + quick_timeout),
-    m_retry(3),
     m_packet(NULL) {
 
 }
diff --git a/src/dht/dht_transaction.h b/src/dht/dht_transaction.h
index 194316d..43b42ab 100644
--- a/src/dht/dht_transaction.h
+++ b/src/dht/dht_transaction.h
@@ -43,6 +43,7 @@
 
 #include "dht/dht_node.h"
 #include "torrent/hash_string.h"
+#include "torrent/static_map.h"
 
 namespace torrent {
 
@@ -93,6 +94,9 @@ public:
   // Number of closest potential contact nodes to keep.
   static const unsigned int max_contacts = 18;
 
+  // Number of closest nodes we actually announce to.
+  static const unsigned int max_announce = 3;
+
   DhtSearch(const HashString& target, const DhtBucket& contacts);
   virtual ~DhtSearch();
 
@@ -178,22 +182,66 @@ public:
   // counts announces instead.
   const_accessor       start_announce();
 
-  void                 receive_peers(const Object& peer_list);
+  void                 receive_peers(SimpleString peers);
   void                 update_status();
 
 private:
   TrackerDht*          m_tracker;
 };
 
+// Possible bencode keys in a DHT message.
+enum dht_keys {
+  key_a_id,
+  key_a_infoHash,
+  key_a_port,
+  key_a_target,
+  key_a_token,
+
+  key_e_0,
+  key_e_1,
+
+  key_q,
+
+  key_r_id,
+  key_r_nodes,
+  key_r_token,
+  key_r_values,
+
+  key_t,
+  key_v,
+  key_y,
+
+  key_LAST,
+};
+
+class DhtMessage : public StaticMap<dht_keys, key_LAST> {
+public:
+  typedef StaticMap<dht_keys, key_LAST> base_type;
+  typedef StaticMapKeys::mapping_type   mapping_type;
+
+  DhtMessage() : data_end(data) {};
+
+  // Must be big enough to hold one of the possible variable-sized reply data.
+  // Currently either:
+  // - error message (size doesn't really matter, it'll be truncated at worst)
+  // - announce token (8 bytes, needs 20 bytes buffer to build)
+  // Never more than one of the above.
+  // And additionally for queries we send:
+  // - transaction ID (3 bytes)
+  static const size_t data_size = 64;
+  char data[data_size];
+  char* data_end;
+};
+
 // Class holding transaction data to be transmitted.
 class DhtTransactionPacket {
 public:
   // transaction packet
-  DhtTransactionPacket(const rak::socket_address* s, const Object& d, unsigned int id, DhtTransaction* t)
+  DhtTransactionPacket(const rak::socket_address* s, const DhtMessage& d, unsigned int id, DhtTransaction* t)
     : m_sa(*s), m_id(id), m_transaction(t) { build_buffer(d); };
 
   // non-transaction packet
-  DhtTransactionPacket(const rak::socket_address* s, const Object& d)
+  DhtTransactionPacket(const rak::socket_address* s, const DhtMessage& d)
     : m_sa(*s), m_id(-cachedTime.seconds()), m_transaction(NULL) { build_buffer(d); };
 
   ~DhtTransactionPacket()                               { delete[] m_data; }
@@ -214,7 +262,7 @@ public:
   DhtTransaction*             transaction()             { return m_transaction; }
 
 private:
-  void                        build_buffer(const Object& data);
+  void                        build_buffer(const DhtMessage& data);
 
   rak::socket_address   m_sa;
   char*                 m_data;
@@ -255,9 +303,6 @@ public:
   int                         quick_timeout()      { return m_quickTimeout; }
   bool                        has_quick_timeout()  { return m_hasQuickTimeout; }
 
-  int                         dec_retry()          { return m_retry--; }
-  int                         retry()              { return m_retry; }
-
   DhtTransactionPacket*       packet()             { return m_packet; }
   void                        set_packet(DhtTransactionPacket* p) { m_packet = p; }
 
@@ -282,7 +327,6 @@ private:
   rak::socket_address    m_sa;
   int                    m_timeout;
   int                    m_quickTimeout;
-  int                    m_retry;
   DhtTransactionPacket*  m_packet;
 };
 
@@ -337,7 +381,7 @@ public:
 
 class DhtTransactionAnnouncePeer : public DhtTransaction {
 public:
-  DhtTransactionAnnouncePeer(const HashString& id, const rak::socket_address* sa, const HashString& infoHash, const std::string& token)
+  DhtTransactionAnnouncePeer(const HashString& id, const rak::socket_address* sa, const HashString& infoHash, SimpleString token)
     : DhtTransaction(-1, 30, id, sa),
       m_infoHash(infoHash),
       m_token(token) { }
@@ -345,11 +389,11 @@ public:
   virtual transaction_type    type()                     { return DHT_ANNOUNCE_PEER; }
 
   const HashString&           info_hash()                { return m_infoHash; }
-  const std::string&          token()                    { return m_token; }
+  SimpleString                token()                    { return m_token; }
 
 private:
   HashString           m_infoHash;
-  std::string          m_token;
+  SimpleString         m_token;
 };
 
 inline bool
diff --git a/src/download/download_constructor.cc b/src/download/download_constructor.cc
index fc2a272..f37f848 100644
--- a/src/download/download_constructor.cc
+++ b/src/download/download_constructor.cc
@@ -36,6 +36,7 @@
 
 #include "config.h"
 
+#include <cstdio>
 #include <cstring>
 #include <string.h>
 #include <rak/functional.h>
diff --git a/src/net/address_list.cc b/src/net/address_list.cc
index 2fc3992..e5cf3cb 100644
--- a/src/net/address_list.cc
+++ b/src/net/address_list.cc
@@ -70,7 +70,7 @@ AddressList::parse_address_normal(const Object::list_type& b) {
 }
 
 void
-AddressList::parse_address_compact(const std::string& s) {
+AddressList::parse_address_compact(SimpleString s) {
   if (sizeof(const SocketAddressCompact) != 6)
     throw internal_error("ConnectionList::AddressList::parse_address_compact(...) bad struct size.");
 
@@ -79,4 +79,18 @@ AddressList::parse_address_compact(const std::string& s) {
 	    std::back_inserter(*this));
 }
 
+void
+AddressList::parse_address_bencode(SimpleString s) {
+  if (sizeof(const SocketAddressCompact) != 6)
+    throw internal_error("AddressList::parse_address_bencode(...) bad struct size.");
+
+  while (s.length() >= 2 + sizeof(SocketAddressCompact)) {
+    if (s[0] != '6' || s[1] != ':')
+      break;
+
+    insert(end(), *reinterpret_cast<const SocketAddressCompact*>(s.c_str() + 2));
+    s = SimpleString(s.c_str() + 2 + sizeof(SocketAddressCompact), s.length() - 2 - sizeof(SocketAddressCompact));
+  }
+}
+
 }
diff --git a/src/net/address_list.h b/src/net/address_list.h
index e4d2009..10dbac4 100644
--- a/src/net/address_list.h
+++ b/src/net/address_list.h
@@ -42,6 +42,7 @@
 #include <rak/socket_address.h>
 
 #include <torrent/object.h>
+#include <torrent/simple_string.h>
 
 namespace torrent {
 
@@ -49,7 +50,8 @@ class AddressList : public std::list<rak::socket_address> {
 public:
   // Parse normal or compact list of addresses and add to AddressList
   void                        parse_address_normal(const Object::list_type& b);
-  void                        parse_address_compact(const std::string& s);
+  void                        parse_address_compact(SimpleString s);
+  void                        parse_address_bencode(SimpleString s);
 
 private:
   static rak::socket_address  parse_address(const Object& b);
diff --git a/src/protocol/extensions.cc b/src/protocol/extensions.cc
index f3464af..7cbf6e3 100644
--- a/src/protocol/extensions.cc
+++ b/src/protocol/extensions.cc
@@ -37,7 +37,7 @@
 #include "config.h"
 
 #include <limits>
-#include <sstream>
+#include <stdarg.h>
 
 #include <cstdio>
 
@@ -49,18 +49,62 @@
 #include "torrent/object_stream.h"
 #include "torrent/peer/connection_list.h"
 #include "torrent/peer/peer_info.h"
-#include "tracker/tracker_http.h"
+#include "torrent/static_map.h"
 #include "manager.h"
 
 #include "extensions.h"
 
 namespace torrent {
 
-const char* ProtocolExtension::message_keys[] = {
-  "HANDSHAKE",
-  "ut_pex",
+enum ext_handshake_keys {
+  key_e,
+  key_m_utPex,
+  key_p,
+  key_reqq,
+  key_v,
+  key_handshake_LAST
 };
 
+enum ext_pex_keys {
+  key_pex_added,
+  key_pex_LAST
+};
+
+class ExtHandshakeMessage : public StaticMap<ext_handshake_keys, key_handshake_LAST> {
+public:
+  typedef StaticMap<ext_handshake_keys, key_handshake_LAST> base_type;
+  typedef StaticMapKeys::mapping_type   mapping_type;
+};
+
+class ExtPEXMessage : public StaticMap<ext_pex_keys, key_pex_LAST> {
+public:
+  typedef StaticMap<ext_pex_keys, key_pex_LAST> base_type;
+  typedef StaticMapKeys::mapping_type   mapping_type;
+};
+
+ExtHandshakeMessage::mapping_type ext_handshake_key_names[ExtHandshakeMessage::length] = {
+  { key_e,            "e" },
+  { key_m_utPex,      "m::ut_pex" },
+  { key_p,            "p" },
+  { key_reqq,         "reqq" },
+  { key_v,            "v" },
+};
+
+ExtPEXMessage::mapping_type ext_pex_key_names[ExtPEXMessage::length] = {
+  { key_pex_added,    "added" },
+};
+
+ext_handshake_keys message_keys[ProtocolExtension::FIRST_INVALID] = {
+  key_handshake_LAST,     // Handshake, not actually used.
+  key_m_utPex,
+};
+
+template<>
+const ExtHandshakeMessage::key_map_init ExtHandshakeMessage::base_type::keyMap(ext_handshake_key_names);
+
+template<>
+const ExtPEXMessage::key_map_init ExtPEXMessage::base_type::keyMap(ext_pex_key_names);
+
 void
 ProtocolExtension::cleanup() {
 //   if (is_default())
@@ -105,23 +149,21 @@ ProtocolExtension::unset_local_enabled(int t) {
 
 DataBuffer
 ProtocolExtension::generate_handshake_message() {
-  Object map = Object::create_map();
-  Object message = Object::create_map();
-
-  map.insert_key(message_keys[UT_PEX], is_local_enabled(UT_PEX) ? 1 : 0);
+  ExtHandshakeMessage message;
 
   // Add "e" key if encryption is enabled, set it to 1 if we require
   // encryption for incoming connections, or 0 otherwise.
   if ((manager->connection_manager()->encryption_options() & ConnectionManager::encryption_allow_incoming) != 0)
-    message.insert_key("e", (manager->connection_manager()->encryption_options() & ConnectionManager::encryption_require) != 0);
+    message[key_e] = (manager->connection_manager()->encryption_options() & ConnectionManager::encryption_require) != 0;
+
+  message[key_p] = manager->connection_manager()->listen_port();
+  message[key_v] = SimpleString("libTorrent " VERSION);
+  message[key_reqq] = 2048;  // maximum request queue size
 
-  message.insert_key("m", map);
-  message.insert_key("p", manager->connection_manager()->listen_port());
-  message.insert_key("v", "libTorrent " VERSION);
-  message.insert_key("reqq", 2048);  // maximum request queue size
+  message[key_m_utPex] = is_local_enabled(UT_PEX) ? UT_PEX : 0;
 
   char buffer[1024];
-  object_buffer_t result = object_write_bencode_c(object_write_to_buffer, NULL, std::make_pair(buffer, buffer + sizeof(buffer)), &message);
+  object_buffer_t result = staticMap_write_bencode_c(object_write_to_buffer, NULL, std::make_pair(buffer, buffer + sizeof(buffer)), message);
 
   int length = result.second - buffer;
   char* copy = new char[length];
@@ -130,21 +172,30 @@ ProtocolExtension::generate_handshake_message() {
   return DataBuffer(copy, copy + length);
 }
 
-DataBuffer
-ProtocolExtension::generate_toggle_message(ProtocolExtension::MessageType t, bool on) {
-  // TODO: Check if we're accepting this message type?
+inline DataBuffer
+ProtocolExtension::build_bencode(size_t maxLength, const char* format, ...) {
+  char* b = new char[maxLength];
 
-  // Manually create bencoded map { "m" => { message_keys[t] => on ? t : 0 } }
-  char* b = new char[32];
-  unsigned int length = snprintf(b, 32, "d1:md%zu:%si%deee", strlen(message_keys[t]), message_keys[t], on ? t : 0);
+  va_list args;
+  va_start(args, format);
+  unsigned int length = vsnprintf(b, maxLength, format, args);
+  va_end(args);
 
-  if (length > 32)
-    throw internal_error("ProtocolExtension::toggle_message wrote past buffer.");
+  if (length > maxLength)
+    throw internal_error("ProtocolExtension::build_bencode wrote past buffer.");
 
   return DataBuffer(b, b + length);
 }
 
 DataBuffer
+ProtocolExtension::generate_toggle_message(MessageType t, bool on) {
+  // TODO: Check if we're accepting this message type?
+
+  // Manually create bencoded map { "m" => { message_keys[t] => on ? t : 0 } }
+  return build_bencode(32, "d1:md%zu:%si%deee", strlen(ext_handshake_key_names[message_keys[t]].key) - 3, ext_handshake_key_names[message_keys[t]].key + 3, on ? t : 0);
+}
+
+DataBuffer
 ProtocolExtension::generate_ut_pex_message(const PEXList& added, const PEXList& removed) {
   if (added.empty() && removed.empty())
     return DataBuffer();
@@ -195,37 +246,30 @@ ProtocolExtension::read_start(int type, uint32_t length, bool skip) {
 
 void
 ProtocolExtension::read_done() {
-  if (m_readType == SKIP_EXTENSION) {
-    delete [] m_read;
-    m_read = NULL;
-    return;
-  }
+  try {
+    switch(m_readType) {
+    case SKIP_EXTENSION:
+      break;
 
-  std::stringstream s(std::string(m_read, m_readPos));
-  s.imbue(std::locale::classic());
+    case HANDSHAKE:
+      parse_handshake();
+      break;
 
-  delete [] m_read;
-  m_read = NULL;
-
-  Object message;
-  s >> message;
+    case UT_PEX:
+      parse_ut_pex();
+      break;
 
-  if (s.fail() || !message.is_map())
-    throw communication_error("Invalid extension message.");
-
-  switch(m_readType) {
-  case HANDSHAKE:
-    parse_handshake(message);
-    break;
-
-  case UT_PEX:
-    parse_ut_pex(message);
-    break;
+    default:
+      throw internal_error("ProtocolExtension::read_done called with invalid extension type.");
+    }
 
-  default:
-    throw internal_error("ProtocolExtension::down_extension_finished called with invalid extension type.");
+  } catch (bencode_error& e) {
+    // Ignore malformed messages.
   }
 
+  delete [] m_read;
+  m_read = NULL;
+
   m_readType = FIRST_INVALID;
   m_flags |= flag_received_ext;
 }
@@ -242,24 +286,22 @@ ProtocolExtension::peer_toggle_remote(int type, bool active) {
 }
 
 void
-ProtocolExtension::parse_handshake(const Object& message) {
-  if (message.has_key_map("m")) {
-    const Object& idMap = message.get_key("m");
+ProtocolExtension::parse_handshake() {
+  ExtHandshakeMessage message;
+  staticMap_read_bencode(m_read, m_readPos, message);
 
-    for (int t = HANDSHAKE + 1; t < FIRST_INVALID; t++) {
-      if (!idMap.has_key_value(message_keys[t]))
-        continue;
+  for (int t = HANDSHAKE + 1; t < FIRST_INVALID; t++) {
+    if (!message[message_keys[t]].is_value())
+      continue;
 
-      uint8_t id = idMap.get_key_value(message_keys[t]);
+    uint8_t id = message[message_keys[t]].as_value();
 
-      set_remote_supported(t);
+    set_remote_supported(t);
 
-      if (id != m_idMap[t - 1]) {
-        peer_toggle_remote(t, id != 0);
-
-        m_idMap[t - 1] = id;
-      }
+    if (id != m_idMap[t - 1]) {
+      peer_toggle_remote(t, id != 0);
 
+      m_idMap[t - 1] = id;
     }
   }
 
@@ -271,29 +313,32 @@ ProtocolExtension::parse_handshake(const Object& message) {
         unset_local_enabled(t);
   }
 
-  if (message.has_key_value("p")) {
-    uint16_t port = message.get_key_value("p");
+  if (message[key_p].is_value()) {
+    uint16_t port = message[key_p].as_value();
 
     if (port > 0)
       m_peerInfo->set_listen_port(port);
   }
 
-  if (message.has_key_value("reqq"))
-    m_maxQueueLength = message.get_key_value("reqq");
+  if (message[key_reqq].is_value())
+    m_maxQueueLength = message[key_reqq].as_value();
 
   m_flags &= ~flag_initial_handshake;
 }
 
 void
-ProtocolExtension::parse_ut_pex(const Object& message) {
+ProtocolExtension::parse_ut_pex() {
   // Ignore message if we're still in the handshake (no connection
   // yet), or no peers are present.
 
+  ExtPEXMessage message;
+  staticMap_read_bencode(m_read, m_readPos, message);
+
   // TODO: Check if pex is enabled?
-  if (!message.has_key_string("added"))
+  if (!message[key_pex_added].is_sstring())
     return;
 
-  const std::string& peers = message.get_key_string("added");
+  SimpleString peers = message[key_pex_added].as_sstring();
   if (peers.empty())
     return;
 
diff --git a/src/protocol/extensions.h b/src/protocol/extensions.h
index 1c370fc..96ed652 100644
--- a/src/protocol/extensions.h
+++ b/src/protocol/extensions.h
@@ -46,6 +46,13 @@
 #include "download/download_info.h"
 #include "net/data_buffer.h"
 
+// Not really important, so no need to make this a configure check.
+#ifdef __GNUC__
+#define ATTRIBUTE_PRINTF(num) __attribute__ ((format (printf, num, num+1)))
+#else
+#define ATTRIBUTE_PRINTF(num)
+#endif
+
 namespace torrent {
 
 class ProtocolExtension {
@@ -71,8 +78,6 @@ public:
   static const int    flag_local_enabled_base    = 1<<8;
   static const int    flag_remote_supported_base = 1<<16;
 
-  static const char*  message_keys[FIRST_INVALID];
-
   // Number of extensions we support, not counting handshake.
   static const int    extension_count = FIRST_INVALID - HANDSHAKE - 1;
 
@@ -128,8 +133,10 @@ public:
   void                reset()                          { std::memset(&m_idMap, 0, sizeof(m_idMap)); }
 
 private:
-  void                parse_handshake(const Object& message);
-  void                parse_ut_pex(const Object& message);
+  void                parse_handshake();
+  void                parse_ut_pex();
+
+  static DataBuffer   build_bencode(size_t maxLength, const char* format, ...) ATTRIBUTE_PRINTF(2);
 
   void                peer_toggle_remote(int type, bool active);
 
diff --git a/src/torrent/Makefile.am b/src/torrent/Makefile.am
index bec124d..820ce52 100644
--- a/src/torrent/Makefile.am
+++ b/src/torrent/Makefile.am
@@ -41,6 +41,9 @@ libsub_torrent_la_SOURCES = \
 	rate.h \
 	resume.cc \
 	resume.h \
+	simple_string.h \
+	static_map.cc \
+	static_map.h \
 	throttle.cc \
 	throttle.h \
 	torrent.cc \
@@ -74,6 +77,8 @@ libtorrentinclude_HEADERS = \
 	poll_select.h \
 	rate.h \
 	resume.h \
+	simple_string.h \
+	static_map.h \
 	throttle.h \
 	torrent.h \
 	tracker.h \
diff --git a/src/torrent/hash_string.h b/src/torrent/hash_string.h
index f62d450..14623f7 100644
--- a/src/torrent/hash_string.h
+++ b/src/torrent/hash_string.h
@@ -44,6 +44,7 @@
 #include <string>
 #include <iterator>
 #include <torrent/common.h>
+#include <torrent/simple_string.h>
 
 namespace torrent {
 
@@ -85,6 +86,8 @@ public:
 
   std::string         str() const                       { return std::string(m_data, size_data); }
 
+  SimpleString        s_str() const                     { return SimpleString(m_data, size_data); }
+
   void                clear(int v = 0)                  { std::memset(data(), v, size()); }
 
   void                assign(const value_type* src)     { std::memcpy(data(), src, size()); }
@@ -96,6 +99,7 @@ public:
   // size_data.
   static const HashString* cast_from(const char* src)        { return (const HashString*)src; }
   static const HashString* cast_from(const std::string& src) { return (const HashString*)src.c_str(); }
+  static const HashString* cast_from(const SimpleString& src){ return (const HashString*)src.c_str(); }
 
   static HashString*  cast_from(char* src)                   { return (HashString*)src; }
 
diff --git a/src/torrent/object.cc b/src/torrent/object.cc
index 2b1cf41..3a0bcae 100644
--- a/src/torrent/object.cc
+++ b/src/torrent/object.cc
@@ -195,6 +195,7 @@ Object::operator = (const Object& src) {
   case TYPE_STRING: m_string = new string_type(*src.m_string); break;
   case TYPE_LIST:   m_list = new list_type(*src.m_list); break;
   case TYPE_MAP:    m_map = new map_type(*src.m_map);  break;
+  case TYPE_SSTRING:m_sstring = src.m_sstring; break;
   }
 
   return *this;
diff --git a/src/torrent/object.h b/src/torrent/object.h
index 7ad040b..6cc4e4a 100644
--- a/src/torrent/object.h
+++ b/src/torrent/object.h
@@ -42,6 +42,7 @@
 #include <list>
 #include <torrent/common.h>
 #include <torrent/exceptions.h>
+#include <torrent/simple_string.h>
 
 namespace torrent {
 
@@ -82,13 +83,16 @@ public:
     TYPE_VALUE,
     TYPE_STRING,
     TYPE_LIST,
-    TYPE_MAP
+    TYPE_MAP,
+    TYPE_SSTRING,    // Only used in StaticMap.
   };
 
   Object()                     : m_flags(TYPE_NONE) {}
   Object(const value_type v)   : m_flags(TYPE_VALUE), m_value(v) {}
   Object(const char* s)        : m_flags(TYPE_STRING), m_string(new string_type(s)) {}
   Object(const string_type& s) : m_flags(TYPE_STRING), m_string(new string_type(s)) {}
+  Object(const char* s, size_t l) : m_flags(TYPE_SSTRING), m_sstring(SimpleString(s, l)) {}
+  Object(SimpleString s)       : m_flags(TYPE_SSTRING), m_sstring(s) {}
   Object(const Object& b);
 
   ~Object() { clear(); }
@@ -96,6 +100,7 @@ public:
   // Move this out of the class namespace, call them create_object_.
   static Object       create_value()  { return Object(value_type()); }
   static Object       create_string() { return Object(string_type()); }
+  static Object       create_sstring(){ return Object(SimpleString()); }
   static Object       create_list()   { Object tmp; tmp.m_flags = TYPE_LIST; tmp.m_list = new list_type(); return tmp; }
   static Object       create_map()    { Object tmp; tmp.m_flags = TYPE_MAP;  tmp.m_map  = new map_type();  return tmp; }
 
@@ -120,6 +125,7 @@ public:
   bool                is_string() const                       { return type() == TYPE_STRING; }
   bool                is_list() const                         { return type() == TYPE_LIST; }
   bool                is_map() const                          { return type() == TYPE_MAP; }
+  bool                is_sstring() const                      { return type() == TYPE_SSTRING; }
 
   value_type&         as_value()                              { check_throw(TYPE_VALUE); return m_value; }
   const value_type&   as_value() const                        { check_throw(TYPE_VALUE); return m_value; }
@@ -133,6 +139,9 @@ public:
   map_type&           as_map()                                { check_throw(TYPE_MAP); return *m_map; }
   const map_type&     as_map() const                          { check_throw(TYPE_MAP); return *m_map; }
 
+  SimpleStringBase&   as_sstring()                            { check_throw(TYPE_SSTRING); return m_sstring; }
+  SimpleString        as_sstring() const                      { check_throw(TYPE_SSTRING); return m_sstring; }
+
   bool                has_key(const key_type& k) const        { check_throw(TYPE_MAP); return m_map->find(k) != m_map->end(); }
   bool                has_key_value(const key_type& k) const  { check_throw(TYPE_MAP); return check(m_map->find(k), TYPE_VALUE); }
   bool                has_key_string(const key_type& k) const { check_throw(TYPE_MAP); return check(m_map->find(k), TYPE_STRING); }
@@ -200,6 +209,7 @@ public:
     string_type*        m_string;
     list_type*          m_list;
     map_type*           m_map;
+    SimpleStringBase    m_sstring;
   };
 };
 
@@ -211,6 +221,7 @@ Object::Object(const Object& b) : m_flags(b.type()) {
   case TYPE_STRING: m_string = new string_type(*b.m_string); break;
   case TYPE_LIST:   m_list = new list_type(*b.m_list); break;
   case TYPE_MAP:    m_map = new map_type(*b.m_map);  break;
+  case TYPE_SSTRING:m_sstring = b.m_sstring; break;
   }
 }
 
@@ -222,6 +233,7 @@ Object::clear() {
   case TYPE_STRING: delete m_string; break;
   case TYPE_LIST:   delete m_list; break;
   case TYPE_MAP:    delete m_map; break;
+  case TYPE_SSTRING:break;
   }
 
   // Only clear type?
diff --git a/src/torrent/object_stream.cc b/src/torrent/object_stream.cc
index 18eb849..73c816b 100644
--- a/src/torrent/object_stream.cc
+++ b/src/torrent/object_stream.cc
@@ -38,12 +38,14 @@
 
 #include <iterator>
 #include <iostream>
+#include <sstream>
 #include <rak/functional.h>
 
 #include "utils/sha1.h"
 
 #include "object.h"
 #include "object_stream.h"
+#include "static_map.h"
 
 namespace torrent {
 
@@ -63,6 +65,18 @@ object_read_string(std::istream* input, std::string& str) {
   return !input->fail();
 }
 
+Object
+object_get_sstring(const char** buffer) {
+  /*const*/ char* next;
+  size_t length = strtoumax(*buffer, &next, 10);
+
+  if (next == *buffer || *next != ':')
+    return Object();
+
+  *buffer = next + 1 + length;
+  return Object(next + 1, length);
+}
+
 // Could consider making this non-recursive, but they seldomly are
 // deep enough to make that worth-while.
 void
@@ -159,6 +173,133 @@ object_read_bencode(std::istream* input, Object* object, uint32_t depth) {
   object->clear();
 }
 
+const char*
+staticMap_read_bencode_c(const char* buffer, const char* bufferEnd, uint32_t depth, Object* values, const StaticMapKeys& keys, bool discard) {
+  if (buffer >= bufferEnd)
+    return bufferEnd;
+
+  // Undecoded bencode object.
+  if (!discard && keys.type() == StaticMapKeys::TYPE_BENCODE) {
+    const char* begin = buffer;
+    buffer = staticMap_read_bencode_c(buffer, bufferEnd, ++depth, values, keys, true);
+    values[keys.index_begin()] = SimpleString(begin, buffer - begin);
+    return buffer;
+  }
+
+  if (!discard && keys.type() == StaticMapKeys::TYPE_BENCODE_LIST && *buffer != 'l')
+    discard = true;
+
+  switch (*buffer) {
+  case 'i': {
+    char* next;
+    intmax_t value = strtoimax(++buffer, &next, 10);
+
+    if (next == buffer || next > bufferEnd || *next != 'e')
+      break;
+
+    if (!discard && keys.type() == StaticMapKeys::TYPE_VALUE)
+      values[keys.index_begin()] = (int64_t)value;
+
+    return next + 1;
+  }
+
+  case 'l': {
+    ++buffer;
+    if (++depth >= 1024)
+      break;
+
+    // Want undecoded bencode list: find end of list.
+    if (!discard && keys.type() == StaticMapKeys::TYPE_BENCODE_LIST) {
+      const char* end = buffer;
+      while (end < bufferEnd && *end != 'e')
+        end = staticMap_read_bencode_c(end, bufferEnd, depth, values, keys, true);
+
+      values[keys.index_begin()] = SimpleString(buffer, end - buffer);
+      return ++end;
+    }
+
+    StaticMapKeys::const_iterator itr = keys.begin();
+    while (buffer != bufferEnd) {
+      if (*buffer == 'e')
+        return ++buffer;
+
+      discard |= itr == keys.end();
+      buffer = staticMap_read_bencode_c(buffer, bufferEnd, depth, values, discard ? keys : *itr, discard);
+
+      if (itr != keys.end())
+        ++itr;
+    }
+
+    break;
+  }
+
+  case 'd': {
+    ++buffer;
+    if (++depth >= 1024)
+      break;
+
+    StaticMapKeys::const_iterator itr = keys.begin();
+    SimpleString last;
+    bool discardThis = discard;
+
+    while (buffer != bufferEnd) {
+      if (*buffer == 'e')
+        return ++buffer;
+    
+      Object keyObj = object_get_sstring(&buffer);
+      if (!keyObj.is_sstring())
+        break;
+
+      SimpleString key = keyObj.as_sstring();
+      if (key.end() >= bufferEnd)
+        break;
+
+      if (key < last) {
+        itr = keys.begin();
+        discardThis = discard;
+      }
+
+      discardThis |= itr == keys.end();
+      int cmp = discardThis ? -1 : key.cmp(itr->key());
+      while (cmp > 0) {
+        if (++itr == keys.end()) {
+          cmp = -1;
+          discardThis = true;
+          break;
+        }
+
+        cmp = key.cmp(itr->key());
+      }
+
+      buffer = staticMap_read_bencode_c(buffer, bufferEnd, depth, values, cmp ? keys : *itr, cmp);
+
+      last = key;
+    }
+
+    break;
+  }
+
+  default:
+    if (*buffer < '0' || *buffer > '9')
+      break;
+
+    Object strObj = object_get_sstring(&buffer);
+    if (!strObj.is_sstring())
+      break;
+
+    SimpleString str = strObj.as_sstring();
+    if (str.end() >= bufferEnd)
+      break;
+
+    if (!discard && keys.type() == StaticMapKeys::TYPE_VALUE)
+      values[keys.index_begin()] = str;
+
+    return str.end();
+  }
+
+  throw bencode_error("Invalid bencode data.");
+}
+
 void
 object_write_bencode(std::ostream* output, const Object* object) {
   char buffer[1024];
@@ -267,6 +408,7 @@ void
 object_write_bencode_c_object(object_write_data_t* output, const Object* object) {
   switch (object->type()) {
   case Object::TYPE_NONE:
+  case Object::TYPE_SSTRING:
     break;
 
   case Object::TYPE_VALUE:
@@ -306,6 +448,86 @@ object_write_bencode_c_object(object_write_data_t* output, const Object* object)
   }
 }
 
+void
+staticMap_write_bencode_c_values(object_write_data_t* output, const Object* values, const StaticMapKeys& keys) {
+  if (keys.type() == StaticMapKeys::TYPE_LIST) {
+    size_t indexEnd = keys.index_begin();
+    while (indexEnd < keys.index_end() && values[indexEnd].type() != Object::TYPE_NONE)
+      indexEnd++;
+
+    // Empty list? Drop it. Sparse lists are not possible so only check first element.
+    if (indexEnd == keys.index_begin())
+      return;
+
+    object_write_bencode_c_char(output, 'l');
+    StaticMapKeys::const_iterator itr = keys.begin();
+    size_t index = keys.index_begin();
+    while (index < indexEnd) {
+      staticMap_write_bencode_c_values(output, values, *itr);
+      index = itr->index_end();
+      if (++itr == keys.end() && index != indexEnd)
+        throw internal_error("staticMap_write_bencode_c_values reached end of list before end of index list.");
+    }
+    object_write_bencode_c_char(output, 'e');
+
+  } else if (keys.type() == StaticMapKeys::TYPE_DICT) {
+    // Find next non-empty entry.
+    size_t next = keys.index_begin();
+    while (values[next].type() == Object::TYPE_NONE)
+      if (++next == keys.index_end())
+        return;
+
+    object_write_bencode_c_char(output, 'd');
+    StaticMapKeys::const_iterator itr = keys.begin();
+    while (next < keys.index_end()) {
+      while (itr->index_end() <= next)
+        if (++itr == keys.end())
+          throw internal_error("staticMap_write_bencode_c_values reached end of keys before end of index list.");
+
+      object_write_bencode_c_value(output, itr->key().size());
+      object_write_bencode_c_char(output, ':');
+      object_write_bencode_c_string(output, itr->key().c_str(), itr->key().size());
+
+      staticMap_write_bencode_c_values(output, values, *itr);
+
+      next = itr->index_end();
+      while (next < keys.index_end() && values[next].type() == Object::TYPE_NONE)
+        ++next;
+    }
+    object_write_bencode_c_char(output, 'e');
+
+  // Undecoded bencode value.
+  } else if (keys.type() == StaticMapKeys::TYPE_BENCODE) {
+    SimpleString value = values[keys.index_begin()].as_sstring();
+    object_write_bencode_c_string(output, value.c_str(), value.size());
+
+  } else if (keys.type() == StaticMapKeys::TYPE_BENCODE_LIST) {
+    SimpleString value = values[keys.index_begin()].as_sstring();
+    object_write_bencode_c_char(output, 'l');
+    object_write_bencode_c_string(output, value.c_str(), value.size());
+    object_write_bencode_c_char(output, 'e');
+
+  } else if (keys.type() != StaticMapKeys::TYPE_VALUE) {
+    throw internal_error("staticMap_write_bencode_c_values received key keys with invalid values type.");
+
+  } else if (values[keys.index_begin()].type() == Object::TYPE_NONE) {
+
+  } else if (values[keys.index_begin()].type() == Object::TYPE_VALUE) {
+    object_write_bencode_c_char(output, 'i');
+    object_write_bencode_c_value(output, values[keys.index_begin()].as_value());
+    object_write_bencode_c_char(output, 'e');
+
+  } else if (values[keys.index_begin()].type() == Object::TYPE_SSTRING) {
+    SimpleString value = values[keys.index_begin()].as_sstring();
+    object_write_bencode_c_value(output, value.size());
+    object_write_bencode_c_char(output, ':');
+    object_write_bencode_c_string(output, value.c_str(), value.size());
+
+  } else {
+    throw internal_error("staticMap_write_bencode_c_values received key keys with invalid values type.");
+  }
+}
+
 object_buffer_t
 object_write_bencode_c(object_write_t writeFunc, void* data, object_buffer_t buffer, const Object* object) {
   object_write_data_t output;
@@ -327,6 +549,32 @@ object_write_bencode_c(object_write_t writeFunc, void* data, object_buffer_t buf
 }
 
 object_buffer_t
+staticMap_write_bencode_c_wrap(object_write_t writeFunc, void* data, object_buffer_t buffer, const Object* values, const StaticMapKeys& map) {
+  object_write_data_t output;
+  output.writeFunc = writeFunc;
+  output.data      = data;
+  output.buffer    = buffer;
+  output.pos       = buffer.first;
+
+  staticMap_write_bencode_c_values(&output, values, map);
+#ifdef USE_EXTRA_DEBUG
+  std::istringstream sstream; 
+  sstream.imbue(std::locale::classic()); 
+  sstream.str(std::string(output.buffer.first, output.pos));
+  Object request; 
+  sstream >> request; 
+  if (sstream.fail())
+    throw internal_error("staticMap_write_bencode_c_wrap failed to create valid bencode format.");
+#endif
+
+  // Don't flush the buffer.
+  if (output.pos == output.buffer.first)
+    return output.buffer;
+
+  return output.writeFunc(output.data, object_buffer_t(output.buffer.first, output.pos));
+}
+
+object_buffer_t
 object_write_to_buffer(void* data, object_buffer_t buffer) {
   if (buffer.first == buffer.second)
     throw internal_error("object_write_to_buffer(...) buffer overflow.");
diff --git a/src/torrent/object_stream.h b/src/torrent/object_stream.h
index 41cf82a..b399bf7 100644
--- a/src/torrent/object_stream.h
+++ b/src/torrent/object_stream.h
@@ -43,6 +43,10 @@
 
 namespace torrent {
 
+template<typename tmpl_key_type, size_t tmpl_length>
+class StaticMap;
+class StaticMapKeys;
+
 std::string object_sha1(const Object* object) LIBTORRENT_EXPORT;
 
 // Assumes the stream's locale has been set to POSIX or C.  Max depth
@@ -53,6 +57,18 @@ void object_read_bencode(std::istream* input, Object* object, uint32_t depth = 0
 // Assumes the stream's locale has been set to POSIX or C.
 void object_write_bencode(std::ostream* output, const Object* object) LIBTORRENT_EXPORT;
 
+// Convert buffer to static key map. Inlined because we don't want
+// a separate wrapper function for each template argument.
+template<typename tmpl_key_type, size_t tmpl_length>
+inline const char*
+staticMap_read_bencode(const char* buffer, const char* bufferEnd, StaticMap<tmpl_key_type, tmpl_length>& map) {
+  return staticMap_read_bencode_c(buffer, bufferEnd, 0, map.values(), map.map(), false);
+};
+
+// Internal use only.
+const char*
+staticMap_read_bencode_c(const char* buffer, const char* bufferEnd, uint32_t depth, Object* values, const StaticMapKeys& keys, bool discard);
+
 std::istream& operator >> (std::istream& input, Object& object) LIBTORRENT_EXPORT;
 std::ostream& operator << (std::ostream& output, const Object& object) LIBTORRENT_EXPORT;
 
@@ -62,6 +78,15 @@ typedef object_buffer_t (*object_write_t)(void* data, object_buffer_t buffer);
 
 object_buffer_t object_write_bencode_c(object_write_t writeFunc, void* data, object_buffer_t buffer, const Object* object) LIBTORRENT_EXPORT;
 
+template<typename tmpl_key_type, size_t tmpl_length>
+inline object_buffer_t
+staticMap_write_bencode_c(object_write_t writeFunc, void* data, object_buffer_t buffer, const StaticMap<tmpl_key_type, tmpl_length>& object) {
+  return staticMap_write_bencode_c_wrap(writeFunc, data, buffer, object.values(), object.map());
+}
+
+// Internal use only.
+object_buffer_t staticMap_write_bencode_c_wrap(object_write_t writeFunc, void* data, object_buffer_t buffer, const Object* values, const StaticMapKeys& keys) LIBTORRENT_EXPORT;
+
 // To char buffer. 'data' is NULL.
 object_buffer_t object_write_to_buffer(void* data, object_buffer_t buffer) LIBTORRENT_EXPORT;
 object_buffer_t object_write_to_sha1(void* data, object_buffer_t buffer) LIBTORRENT_EXPORT;
diff --git a/src/torrent/simple_string.h b/src/torrent/simple_string.h
new file mode 100644
index 0000000..8eaf3b7
--- /dev/null
+++ b/src/torrent/simple_string.h
@@ -0,0 +1,129 @@
+// libTorrent - BitTorrent library
+// Copyright (C) 2005-2008, Jari Sundell
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 2 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+// 
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+//
+// In addition, as a special exception, the copyright holders give
+// permission to link the code of portions of this program with the
+// OpenSSL library under certain conditions as described in each
+// individual source file, and distribute linked combinations
+// including the two.
+//
+// You must obey the GNU General Public License in all respects for
+// all of the code used other than OpenSSL.  If you modify file(s)
+// with this exception, you may extend this exception to your version
+// of the file(s), but you are not obligated to do so.  If you do not
+// wish to do so, delete this exception statement from your version.
+// If you delete this exception statement from all source files in the
+// program, then also delete it here.
+//
+// Contact:  Jari Sundell <jaris@ifi.uio.no>
+//
+//           Skomakerveien 33
+//           3185 Skoppum, NORWAY
+
+// A simple string with no constructors (i.e. POD) plus a derived
+// class with constructors and conversion operators. In most cases,
+// SimpleString is the class to use, except in unions where it needs
+// to be SimpleStringBase.
+//
+// For efficient conversion from C string literals, depends on the
+// compiler optimizing strlen("literal") to an integer literal.
+// Then a comparison with either a C string literal or a SimpleString
+// literal is a memcmp call plus (if equal) a comparison of the lengths.
+
+#ifndef LIBTORRENT_SIMPLE_STRING_H
+#define LIBTORRENT_SIMPLE_STRING_H
+
+#include <cstring>
+#include <memory>
+#include <string>
+#include <torrent/common.h>
+
+namespace torrent {
+
+// Simple string base class (POD).
+struct LIBTORRENT_EXPORT SimpleStringBase {
+  int               cmp(const SimpleStringBase& other) const;
+
+  char              operator [] (size_t index) const  { return m_data[index]; }
+
+  const char*       begin() const                     { return m_data; }
+  const char*       end() const                       { return m_data + m_length; }
+
+  // NOTE: Unlike std::string, SimpleString's c_str() is NOT guaranteed to be zero-terminated!
+  const char*       c_str() const                     { return m_data; }
+  const char*       data() const                      { return m_data; }
+
+  bool              empty() const                     { return !m_length; }
+  size_t            length() const                    { return m_length; }
+  size_t            size() const                      { return m_length; }
+
+  std::string       str() const                                   { return std::string(m_data, m_length); }
+  std::string       substr(size_t pos = 0, size_t n = npos) const { return std::string(m_data + pos, std::min(m_length - pos, n)); }
+
+  // Allocates a copy of the string and returns it.
+  SimpleStringBase  copy() const;
+
+  static const size_t npos = static_cast<size_t>(-1);
+
+protected:
+  const char* m_data;
+  size_t      m_length;
+};
+
+// Conversion helper class, we don't want constructors
+// in the base class to be able to put it in a union.
+struct LIBTORRENT_EXPORT SimpleString : public SimpleStringBase {
+  typedef SimpleStringBase base_type;
+
+  SimpleString()                        { m_data = ""; m_length = 0; }
+  SimpleString(const base_type& s)      { m_data = s.c_str(); m_length = s.length(); }
+  SimpleString(const std::string& s)    { m_data = s.c_str(); m_length = s.length(); }
+  SimpleString(const char* s)           { m_data = s; m_length = strlen(s); }
+  SimpleString(const char* s, size_t l) { m_data = s; m_length = l; }
+};
+
+inline int
+SimpleStringBase::cmp(const SimpleStringBase& other) const {
+  int cmp = memcmp(m_data, other.m_data, std::min(m_length, other.m_length));
+  return cmp ? cmp : m_length - other.m_length;
+}
+
+inline SimpleStringBase
+SimpleStringBase::copy() const {
+  char* data = new char[m_length + 1];
+  memcpy(data, m_data, m_length);
+  data[m_length] = 0;
+  return SimpleString(data, m_length);
+}
+
+inline bool operator == (const SimpleStringBase& one, const SimpleStringBase& other) { return one.cmp(other) == 0; }
+inline bool operator != (const SimpleStringBase& one, const SimpleStringBase& other) { return one.cmp(other) != 0; }
+inline bool operator <= (const SimpleStringBase& one, const SimpleStringBase& other) { return one.cmp(other) <= 0; }
+inline bool operator <  (const SimpleStringBase& one, const SimpleStringBase& other) { return one.cmp(other) <  0; }
+inline bool operator >= (const SimpleStringBase& one, const SimpleStringBase& other) { return one.cmp(other) >= 0; }
+inline bool operator >  (const SimpleStringBase& one, const SimpleStringBase& other) { return one.cmp(other) >  0; }
+
+inline bool operator == (const SimpleStringBase& one, const char* other) { return one.cmp(SimpleString(other)) == 0; }
+inline bool operator != (const SimpleStringBase& one, const char* other) { return one.cmp(SimpleString(other)) != 0; }
+inline bool operator <= (const SimpleStringBase& one, const char* other) { return one.cmp(SimpleString(other)) <= 0; }
+inline bool operator <  (const SimpleStringBase& one, const char* other) { return one.cmp(SimpleString(other)) <  0; }
+inline bool operator >= (const SimpleStringBase& one, const char* other) { return one.cmp(SimpleString(other)) >= 0; }
+inline bool operator >  (const SimpleStringBase& one, const char* other) { return one.cmp(SimpleString(other)) >  0; }
+
+}
+
+#endif
diff --git a/src/torrent/static_map.cc b/src/torrent/static_map.cc
new file mode 100644
index 0000000..b71f257
--- /dev/null
+++ b/src/torrent/static_map.cc
@@ -0,0 +1,123 @@
+// libTorrent - BitTorrent library
+// Copyright (C) 2005-2008, Jari Sundell
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 2 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+// 
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+//
+// In addition, as a special exception, the copyright holders give
+// permission to link the code of portions of this program with the
+// OpenSSL library under certain conditions as described in each
+// individual source file, and distribute linked combinations
+// including the two.
+//
+// You must obey the GNU General Public License in all respects for
+// all of the code used other than OpenSSL.  If you modify file(s)
+// with this exception, you may extend this exception to your version
+// of the file(s), but you are not obligated to do so.  If you do not
+// wish to do so, delete this exception statement from your version.
+// If you delete this exception statement from all source files in the
+// program, then also delete it here.
+//
+// Contact:  Jari Sundell <jaris@ifi.uio.no>
+//
+//           Skomakerveien 33
+//           3185 Skoppum, NORWAY
+
+#include "config.h"
+
+#include "static_map.h"
+
+namespace torrent {
+
+inline int
+StaticMapKeys::check_key_order(SimpleString key) {
+  int cmp = empty() ? -1 : back().key().cmp(key);
+  if (cmp > 0) {
+    if (type() == TYPE_LIST)
+      cmp = -1;  // List order is given by indices, not alphabetically.
+    else
+      throw internal_error("StaticMapKeys::StaticMapKeys() called with unsorted keys.");
+  }
+
+  return cmp;
+}
+
+StaticMapKeys::StaticMapKeys(const mapping_type* key_list, size_t length) 
+  : m_key(SimpleString("root", 4)),
+    m_indexBegin(0),
+    m_indexEnd(0),
+    m_type(key_list[0].key[0] == '[' ? TYPE_LIST : TYPE_DICT) {
+
+  for (size_t index = 0; index < length; index++, key_list++) {
+    if (key_list->index != index)
+      throw internal_error("StaticMapKeys::StaticMapKeys() used with list not in index order.");
+
+    StaticMapKeys* curMap = this;
+    const char* key = key_list->key;
+    while (key != NULL && *key) {
+      curMap->set_end(index + 1);
+
+      const char* sep = key + 1 + strcspn(key + 1, ":[");
+      SimpleString keyStr(key, sep - key);
+
+      // New key, in correct order? Or same key as before?
+      int cmp = curMap->check_key_order(keyStr);
+
+      if (sep[0] == 0) {
+        curMap->insert(curMap->end(), StaticMapKeys(keyStr, TYPE_VALUE, index, index + 1));
+        break;
+
+      } else if (sep[0] == '[' && sep[1] == ']' && sep[2] == 0) {
+        curMap->insert(curMap->end(), StaticMapKeys(keyStr, TYPE_BENCODE_LIST, index, index + 1));
+        break;
+
+      } else if (sep[0] == ':' && sep[1] == ':' && sep[2] == 0) {
+        curMap->insert(curMap->end(), StaticMapKeys(keyStr, TYPE_BENCODE, index, index + 1));
+        break;
+      }
+
+      if (sep[0] == ':' && sep[1] == ':') {
+        if (cmp < 0)
+          curMap->insert(curMap->end(), StaticMapKeys(keyStr, TYPE_DICT, index, index + 1));
+        else if (curMap->back().type() != TYPE_DICT)
+          throw internal_error("StaticMapKeys::StaticMapKeys() called with a mixed dictionary/list entry.");
+
+        curMap = &curMap->back();
+        key = sep + 2;
+
+      } else if (sep[0] == '[' && sep[1] >= '0' && sep[1] <= '9') {
+        key = sep++;
+        while (*sep >= '0' && *sep <= '9')
+                ++sep;
+        if (*sep != ']')
+          throw internal_error("StaticMapKeys::StaticMapKeys() called with invalid list index.");
+
+        if (cmp < 0)
+          curMap->insert(curMap->end(), StaticMapKeys(keyStr, TYPE_LIST, index, index + 1));
+        else if (curMap->back().type() != TYPE_LIST)
+          throw internal_error("StaticMapKeys::StaticMapKeys() called with a mixed dictionary/list entry.");
+
+        curMap = &curMap->back();
+
+      } else {
+        throw internal_error("StaticMapKeys::StaticMapKeys() called with unsupported key type.");
+      }
+    }
+  }
+
+  if (index_end() != length)
+    throw internal_error("StaticMapKeys::StaticMapKeys() is missing values.");
+}
+
+}
diff --git a/src/torrent/static_map.h b/src/torrent/static_map.h
new file mode 100644
index 0000000..d862f16
--- /dev/null
+++ b/src/torrent/static_map.h
@@ -0,0 +1,158 @@
+// libTorrent - BitTorrent library
+// Copyright (C) 2005-2008, Jari Sundell
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 2 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+// 
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+//
+// In addition, as a special exception, the copyright holders give
+// permission to link the code of portions of this program with the
+// OpenSSL library under certain conditions as described in each
+// individual source file, and distribute linked combinations
+// including the two.
+//
+// You must obey the GNU General Public License in all respects for
+// all of the code used other than OpenSSL.  If you modify file(s)
+// with this exception, you may extend this exception to your version
+// of the file(s), but you are not obligated to do so.  If you do not
+// wish to do so, delete this exception statement from your version.
+// If you delete this exception statement from all source files in the
+// program, then also delete it here.
+//
+// Contact:  Jari Sundell <jaris@ifi.uio.no>
+//
+//           Skomakerveien 33
+//           3185 Skoppum, NORWAY
+
+#ifndef LIBTORRENT_STATIC_MAP_H
+#define LIBTORRENT_STATIC_MAP_H
+
+#include <vector>
+#include <torrent/common.h>
+#include <torrent/object.h>
+#include <torrent/simple_string.h>
+
+// StaticMap: holds a pre-defined subset of possible bencode keys and stores
+// their values in a flat array for fast decoding, key access and encoding.
+// Makes no copies, so the underlying data buffer must outlive the map object.
+
+// With this, the complexity for bencoding and bdecoding a StaticMap object
+// is O(n). The access to any of the pre-defined keys is O(1). Access to
+// other keys is not supported, they are dropped while bdecoding. Decoded
+// Object types are either VALUE, SSTRING or NONE (if key was not present).
+
+// To use, define an enum of all required keys, and use this type along with
+// the number of possible keys in the StaticMap template arguments. Define
+// the enum -> key string as array of StaticMapKeys::mapping_type. Define
+// the static keyMap variable, most simply by defining base_type in your
+// derived map class, like this:
+// template<> const Derived::key_map_init Derived::base_type::keyMap(key_list);
+
+// The argument of the constructor of this static keyMap object is a list
+// of mapping_type entries. For efficiency, they must be ordered in
+// increasing number of the index, and increasing alphabetical order
+// (or more specifically, the bencode order) at the same time. In other words,
+// the original enum must also be in alphabetical order of the keys the enum
+// values refer to.
+
+// Format of the key specifications ("..." may contain any number of further keys):
+// "foo::..."   makes foo a bencode dictionary
+// "foo[0]..."  makes foo a bencode list
+// "foo::"      makes foo an undecoded bencode value (may contain arbitrary bencode data)
+// "foo[]"      makes foo an undecoded list of bencode values (like the above but adding the 'l' and 'e' indicators)
+// "foo"        makes foo an integer or string value (automatic)
+//
+// Examples:
+// "baz"            refers to a single value for key "baz"
+// "foo::a[0]::bar" refers to a single value for key "bar" in the dictionary at index 0 of the list for key "a" in dictionary "foo"
+// "foo::a[1]"      refers to a single value at index 1 of the list for key "a" in the dictionary "foo"
+// "zoo::"          refers to a bdecoded value for key "zoo"
+//
+// If the four values are 4, 5, "6" and 7, this would be bencoded as d3:bazi4e3:food1:ald3:bari5ee1:6ee3:zooi7ee
+//
+// Note that sparse lists are not possible, you must explicitly specify all needed entries starting from index 0,
+// and when bencoding, the first unset value terminates the list.
+
+namespace torrent {
+
+// Hierarchical structure mapping bencode keys to flat array indices.
+class LIBTORRENT_EXPORT StaticMapKeys : public std::vector<StaticMapKeys> {
+public:
+  typedef std::vector<StaticMapKeys> base_type;
+
+  struct mapping_type {
+    size_t      index;
+    const char* key;
+  };
+
+  enum value_type {
+    TYPE_VALUE,
+    TYPE_LIST,
+    TYPE_DICT,
+    TYPE_BENCODE,
+    TYPE_BENCODE_LIST,
+  };
+
+  StaticMapKeys(const mapping_type* key_list, size_t length);
+
+  void               set_end(size_t end)   { m_indexEnd = end; }
+
+  size_t             index_begin() const   { return m_indexBegin; }
+  size_t             index_end() const     { return m_indexEnd; }
+
+  value_type         type() const          { return m_type; }
+
+  SimpleString       key() const           { return m_key; }
+
+private:
+  StaticMapKeys(SimpleString key, value_type type, size_t begin, size_t end)
+    : m_key(key), m_indexBegin(begin), m_indexEnd(end), m_type(type) {}
+
+  int                check_key_order(SimpleString key);
+
+  SimpleString       m_key;
+  size_t             m_indexBegin;
+  size_t             m_indexEnd;
+  value_type         m_type;
+};
+
+template<typename tmpl_key_type, size_t tmpl_length>
+class LIBTORRENT_EXPORT StaticMap {
+public:
+  typedef Object&         value_type;
+  typedef tmpl_key_type   key_type;
+  typedef StaticMapKeys   key_map_type;
+  typedef Object          list_type[tmpl_length];
+
+  Object&              operator [] (key_type key)        { return m_values[key]; }
+  const Object&        operator [] (key_type key) const  { return m_values[key]; }
+
+  const key_map_type&  map() const                       { return keyMap; }
+
+  list_type&           values()                          { return m_values; }
+  const list_type&     values() const                    { return m_values; }
+
+  static const size_t  length = tmpl_length;
+
+private:
+  struct key_map_init : public key_map_type {
+    key_map_init(key_map_type::mapping_type* key_list) : key_map_type(key_list, tmpl_length) {};
+  };
+  static const key_map_init                keyMap;
+
+  list_type      m_values;
+};
+
+}
+
+#endif
diff --git a/src/tracker/tracker_dht.cc b/src/tracker/tracker_dht.cc
index c63ce58..309fcf2 100644
--- a/src/tracker/tracker_dht.cc
+++ b/src/tracker/tracker_dht.cc
@@ -115,13 +115,11 @@ TrackerDht::type() const {
 }
 
 void
-TrackerDht::receive_peers(const Object& peer_list) {
+TrackerDht::receive_peers(SimpleString peers) {
   if (!is_busy())
     throw internal_error("TrackerDht::receive_peers called while not busy.");
 
-  Object::list_type peers = peer_list.as_list();
-  for (Object::list_type::const_iterator itr = peers.begin(); itr != peers.end(); ++itr)
-    m_peers.parse_address_compact(itr->as_string());
+  m_peers.parse_address_bencode(peers);
 }
 
 void
diff --git a/src/tracker/tracker_dht.h b/src/tracker/tracker_dht.h
index d197e61..d096b46 100644
--- a/src/tracker/tracker_dht.h
+++ b/src/tracker/tracker_dht.h
@@ -71,7 +71,7 @@ public:
 
   bool                has_peers() const                { return !m_peers.empty(); }
 
-  void                receive_peers(const Object& peer_list);
+  void                receive_peers(SimpleString peers);
   void                receive_success();
   void                receive_failed(const char* msg);
   void                receive_progress(int replied, int contacted);