changed hash calculation of lobby connexion challenge to make it only usable by the receiver (thx bob to point me out this security issue!)

git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@4895 b45a01b8-16f6-495d-af2f-9b41ad6348cc
This commit is contained in:
csoler 2012-02-06 21:00:09 +00:00
parent b4d9828438
commit aa4eecf467
2 changed files with 43 additions and 22 deletions

View File

@ -39,8 +39,10 @@
/****
* #define CHAT_DEBUG 1
****/
#define CHAT_DEBUG 1
static const int CONNECTION_CHALLENGE_MAX_COUNT = 20 ; // sends a connexion challenge every 20 messages
static const time_t CONNECTION_CHALLENGE_MAX_MSG_AGE = 30 ; // maximum age of a message to be used in a connexion challenge
static const int CONNECTION_CHALLENGE_MIN_DELAY = 15 ; // sends a connexion at most every 15 seconds
static const int LOBBY_CACHE_CLEANING_PERIOD = 10 ; // clean lobby caches every 10 secs (remove old messages)
static const time_t MAX_KEEP_MSG_RECORD = 1200 ; // keep msg record for 1200 secs max.
@ -1813,33 +1815,36 @@ void p3ChatService::handleConnectionChallenge(RsChatLobbyConnectChallengeItem *i
std::cerr << " Peer Id = " << item->PeerId() << std::endl;
#endif
time_t now = time(NULL) ;
ChatLobbyId lobby_id ;
std::string ownId = rsPeers->getOwnId();
bool found = false ;
{
RsStackMutex stack(mChatMtx); /********** STACK LOCKED MTX ******/
for(std::map<ChatLobbyId,ChatLobbyEntry>::iterator it(_chat_lobbys.begin());it!=_chat_lobbys.end() && !found;++it)
for(std::map<ChatLobbyMsgId,time_t>::const_iterator it2(it->second.msg_cache.begin());it2!=it->second.msg_cache.end() && !found;++it2)
{
uint64_t code = makeConnexionChallengeCode(it->first,it2->first) ;
#ifdef CHAT_DEBUG
std::cerr << " Lobby_id = 0x" << std::hex << it->first << ", msg_id = 0x" << it2->first << ": code = 0x" << code << std::dec << std::endl ;
#endif
if(code == item->challenge_code)
if(it2->second + CONNECTION_CHALLENGE_MAX_MSG_AGE + 5 > now) // any msg not older than 5 seconds plus max challenge count is fine.
{
uint64_t code = makeConnexionChallengeCode(ownId,it->first,it2->first) ;
#ifdef CHAT_DEBUG
std::cerr << " Challenge accepted for lobby " << std::hex << it->first << ", for chat msg " << it2->first << std::dec << std::endl ;
std::cerr << " Sending connection request to peer " << item->PeerId() << std::endl;
std::cerr << " Lobby_id = 0x" << std::hex << it->first << ", msg_id = 0x" << it2->first << ": code = 0x" << code << std::dec << std::endl ;
#endif
lobby_id = it->first ;
found = true ;
if(code == item->challenge_code)
{
#ifdef CHAT_DEBUG
std::cerr << " Challenge accepted for lobby " << std::hex << it->first << ", for chat msg " << it2->first << std::dec << std::endl ;
std::cerr << " Sending connection request to peer " << item->PeerId() << std::endl;
#endif
// also add the peer to the list of participating friends
it->second.participating_friends.insert(item->PeerId()) ;
lobby_id = it->first ;
found = true ;
// also add the peer to the list of participating friends
it->second.participating_friends.insert(item->PeerId()) ;
}
}
}
}
if(found) // send invitation. As the peer already has the lobby, the invitation will most likely be accepted.
@ -1869,19 +1874,19 @@ void p3ChatService::sendConnectionChallenge(ChatLobbyId lobby_id)
}
time_t now = time(NULL) ;
uint64_t code = 0 ;
ChatLobbyMsgId msg_id = 0 ;
for(std::map<ChatLobbyMsgId,time_t>::const_iterator it2(it->second.msg_cache.begin());it2!=it->second.msg_cache.end();++it2)
if(it2->second + 20 > now) // any msg not older than 20 seconds is fine.
if(it2->second + CONNECTION_CHALLENGE_MAX_MSG_AGE > now) // any msg not older than 20 seconds is fine.
{
code = makeConnexionChallengeCode(lobby_id,it2->first) ;
msg_id = it2->first ;
#ifdef CHAT_DEBUG
std::cerr << " Using msg id 0x" << std::hex << it2->first << ", challenge code = " << code << std::dec << std::endl;
std::cerr << " Using msg id 0x" << std::hex << it2->first << std::dec << std::endl;
#endif
break ;
}
if(code == 0)
if(msg_id == 0)
{
std::cerr << " No suitable message found in cache. Weird !!" << std::endl;
return ;
@ -1896,6 +1901,11 @@ void p3ChatService::sendConnectionChallenge(ChatLobbyId lobby_id)
{
RsChatLobbyConnectChallengeItem *item = new RsChatLobbyConnectChallengeItem ;
uint64_t code = makeConnexionChallengeCode(*it,lobby_id,msg_id) ;
#ifdef CHAT_DEBUG
std::cerr << " Sending collexion challenge code 0x" << std::hex << code << std::dec << " to peer " << *it << std::endl;
#endif
item->PeerId(*it) ;
item->challenge_code = code ;
@ -1903,9 +1913,20 @@ void p3ChatService::sendConnectionChallenge(ChatLobbyId lobby_id)
}
}
uint64_t p3ChatService::makeConnexionChallengeCode(ChatLobbyId lobby_id,ChatLobbyMsgId msg_id)
uint64_t p3ChatService::makeConnexionChallengeCode(const std::string& peer_id,ChatLobbyId lobby_id,ChatLobbyMsgId msg_id)
{
return ((uint64_t)lobby_id) ^ (uint64_t)msg_id ;
uint64_t result = 0 ;
for(uint32_t i=0;i<peer_id.size();++i)
{
result += msg_id ;
result ^= result >> 35 ;
result += result << 6 ;
result ^= peer_id[i] * lobby_id ;
result += result << 26 ;
result ^= result >> 13 ;
}
return result ;
}
void p3ChatService::getChatLobbyList(std::list<ChatLobbyInfo>& linfos)

View File

@ -246,7 +246,7 @@ class p3ChatService: public p3Service, public p3Config, public pqiMonitor
void locked_initLobbyBouncableObject(const ChatLobbyId& id,RsChatLobbyBouncingObject&) ;
static std::string makeVirtualPeerId(ChatLobbyId) ;
static uint64_t makeConnexionChallengeCode(ChatLobbyId lobby_id,ChatLobbyMsgId msg_id) ;
static uint64_t makeConnexionChallengeCode(const std::string& peer_id,ChatLobbyId lobby_id,ChatLobbyMsgId msg_id) ;
void locked_printDebugInfo() const ;
RsChatAvatarItem *makeOwnAvatarItem() ;