CAIPList Class Reference

The purpose of this class is to store a list of IP-Addresses. More...

Public Member Functions
	CAIPList ()
	TODO: Fix LOG_TRAFFIC output which is not done anymore, as per default no log message are ommited... More...
	CAIPList (UINT32 allowedConnections)
	Constructs a empty CAIPList, there allowedConnections insertions are allowed, until an error is returned. More...
	~CAIPList ()
	Deletes the IPList and frees all used resources. More...
SINT32	insertIP (const UINT8 ip[4])
	Inserts the IP-Address into the list. More...
SINT32	removeIP (const UINT8 ip[4])
	Removes the IP-Address from the list. More...

Private Attributes
UINT32	m_allowedConnections
volatile VOLATILE_PIPLIST *	m_HashTable
CAMutex *	m_pMutex

Detailed Description

The purpose of this class is to store a list of IP-Addresses.

If an IP-Address is inserted more than 'x' times, than an error is returned. The First mix uses this functionalty to do some basic Denial Of Service defense. If someone tries to do connection flooding to the First Mix, only 'x' connections are accepted and the others are droped. The internal organisation is a hash-table with overrun lists. The hashtable has 0x10000 buckets. The last two bytes of an IP-Address are the hash-key.

Note

This class only supports IPv4.

Warning

If there is less memory, CAIPList will crash!

Version

1.0 first version

Constructor & Destructor Documentation

CAIPList() [1/2]

CAIPList::CAIPList

(

)

TODO: Fix LOG_TRAFFIC output which is not done anymore, as per default no log message are ommited...

Constructs an empty CAIPList. The default number MAX_IP_CONNECTIONS of allowed insertions is used

References getRandom(), m_allowedConnections, m_HashTable, m_pMutex, and MAX_IP_CONNECTIONS.

CAIPList() [2/2]

CAIPList::CAIPList

(

UINT32

allowedConnections

)

Constructs a empty CAIPList, there allowedConnections insertions are allowed, until an error is returned.

Parameters

allowedConnections

number of insertions of the same IP-Address, until an error is returned

References getRandom(), m_allowedConnections, m_HashTable, and m_pMutex.

~CAIPList()

CAIPList::~CAIPList

(

)

Deletes the IPList and frees all used resources.

References m_HashTable, m_pMutex, and _iplist_t::next.

Member Function Documentation

insertIP()

SINT32 CAIPList::insertIP

(

const UINT8

ip[4]

)

Inserts the IP-Address into the list.

If the IP-Address is already in the list then the number of insert() called for this IP-Adress is returned. If this number is larger than m_allowedConnections an error is returned. Intern handelt es sich um eine Hashtabelle mit Ueberlaufliste. Die letzten 16 Bit der IP-Adresse bilden dabei den Hashkey. Die Hashtabelle hat 16^2 Eintraege. In den Ueberlauflisten der einzelnen Hasheintraege sind die ersten 16 Bit der IP-Adresse gespeichert.

Parameters

ip	the IP-Address to insert

Returns

number of inserts for this IP-Address

Return values

E_UNKNOWN

if an error occured or an IP is inserted more than m_allowedConnections times

References _iplist_t::count, E_SUCCESS, E_UNKNOWN, _iplist_t::ip, CAMutex::lock(), m_allowedConnections, m_HashTable, m_pMutex, _iplist_t::next, CAMsg::printMsg(), and CAMutex::unlock().

removeIP()

SINT32 CAIPList::removeIP

(

const UINT8

ip[4]

)

Removes the IP-Address from the list.

Parameters

ip	IP-Address to remove

Returns

the remaining count of inserts for this IP-Address.

Return values

0	if IP-Address is delete form the list

References _iplist_t::count, E_SUCCESS, _iplist_t::ip, CAMutex::lock(), m_HashTable, m_pMutex, _iplist_t::next, CAMsg::printMsg(), and CAMutex::unlock().

Referenced by CAFirstMixA::closeConnection(), CAFirstMix::doUserLogin_internal(), and CAFirstMixB::loop().

Member Data Documentation

m_allowedConnections

UINT32 CAIPList::m_allowedConnections

private

Referenced by CAIPList(), and insertIP().

m_HashTable

volatile VOLATILE_PIPLIST* CAIPList::m_HashTable

private

Referenced by CAIPList(), insertIP(), removeIP(), and ~CAIPList().

m_pMutex

CAMutex* CAIPList::m_pMutex

private

Referenced by CAIPList(), insertIP(), removeIP(), and ~CAIPList().