CIcmp - это ICMP класс для MFCАвтор JayWheeler.
В ICMP определены следующие типы сообщений:
The CIcmp класс наследуется от MFC классаCSocket. Этот класс был разработан, используя Microsoft VisualC++ версии 4.2 и MFC, и был протестирован как на WindowsNT 4.0 Workstation так и на Server используя WindowsNT Winsock 2. Эта версия класса CIcmp включает в себя только Эхо-запросы описаные в RFC792. Для более детального изучения, почитайте RFC792 - Internet Control Message Protocol, DARPA Internet Program, Protocol Specification. CIcmp может быть легко расширен для полной поддержки спецификации RFC792.
CIcmp содержит следующие методы для системы WindowsNT 4.0 включающей интерфейс WindowsNT Winsock 2: CloseIcmpSocket
BOOL OpenNewSocket (HWND hWnd, BOOL OpenNewSocket (HWND hWnd, Открывает SOCKET типа AType семейства AFamily и протоколом AProtocol. Если AFamily, AType и AProtocol не поддерживаются, то SOCKET становится RAW сокетом с ICMP протоколом. hWnd это хэндл (GetSafeHwnd) окна, которое будет обрабатывать сообщения поступающие с ассинхронного сокета, NotificationMessage сообщения, которые должен обрабатывать сокет, и NotifyEvents это сообщение, которое будет поступать в окно при возникновении на сокете события. icmpSocketError и icmpSocketErrorMod будут содержать TRUE при удачном завершении операции, иначе FALSE. BOOL Connect (LPINT ReceiveTimeout, BOOL Connect (LPINT ReceiveTimeout, Connects a CIcmp object to a socket of specified family (AFamily), type (AType) and protocol (AProtocol). If AFamily, AType and AProtocol are not provided, connects a CIcmp object to a RAW socket with ICMP protocol. ReceiveTimeout and SendTimeout specifies the receive and transmit timeouts. Sets icmpSocketError and icmpSocketErrorMod to indicate the type of error, and returns TRUE if successful, else FALSE. icmpSocketError and icmpSocketErrorMod are preserved until the next operation on this CIcmp object is performed. int CloseIcmpSocket(void) Closes a socket associated with a CIcmp object. Sets icmpSocketError and icmpSocketErrorMod to indicate the type of error, and returns the integer result of the operation. icmpSocketError and icmpSocketErrorMod are preserved until the next operation on this CIcmp object is performed. int SetAsynchNotification (HWND hWnd, Sets the window (process) to notify when a network event on the socket associated with the CIcmp object occurs. Message is the message number to send to the window, and Events is the event mask to notify on. Sets icmpSocketError and icmpSocketErrorMod to indicate the type of error, and returns the integer result of the operation. icmpSocketError and icmpSocketErrorMod are preserved until the next operation on this CIcmp object is performed. int SetTTL (int TTL) Set the TTL (Time-To-Live) option on the socket associated with a CIcmp object. The TTL value specifies the number of seconds an Internet datagram is to exist. Since each gateway encountered along the trip to the specified host decrements the TTL value by 1, TTL specifies the number of hops (gateways) to query before a response is returned. By incrementing the TTL from 1 to (number of hops to final destination), a TraceRoute function can be performed. In order to reach a designated host, TTL must be at least the number of gateways encountered on the way to the host, plus 1 (for the host itself). Sets icmpSocketError and icmpSocketErrorMod to indicate the type of error, and returns the integer result of the operation. icmpSocketError and icmpSocketErrorMod are preserved until the next operation on this CIcmp object is performed. int Ping (LPSTR pIcmpBuffer, int IcmpBufferSize) Sends an ICMP Echo Request (ping) message to the host indicated in the CIcmp variable icmpSockAddr. The CIcmp variables icmpCurSeq and icmpCurId are sent in the buffer referenced by pIcmpBuffer. The referenced buffer must be large enough to hold DataLen bytes plus the size of the ICMP message header. The CIcmp variable icmpPingSentAt is set to the time value at the time the ping message is sent. Sets icmpSocketError and icmpSocketErrorMod to indicate the type of error, and returns the integer result of the operation. icmpSocketError and icmpSocketErrorMod are preserved until the next operation on this CIcmp object is performed. unsigned short IcmpChecksum (unsigned short FAR *lpBuf, int Len) Computes the ICMP checksum of the data in the buffer referenced by lpBuf for Len bytes. Returns an unsigned integer value of the computed checksum. unsigned long GetIPAddress (LPSTR iHostName) Returns the value of the IP address of the host pointed by iHostName as an unsigned long in network byte order, as described in inet_aton. Sets iHostName to the value of the host name returned in icmpHostEnt. Requires the message number to send to the window, and the events to notify on. Sets CIcmp variable icmpSockAddr fields appropriately, leaving the IP address in icmpSockAddr.sin_addr, and the type of address in icmpSockAddr.sin_family. Also sets icmpHostEnt fields appropriately Sets icmpSocketError and icmpSocketErrorMod to indicate the type of error, and returns the integer result of the operation. icmpSocketError and icmpSocketErrorMod are preserved until the next operation on this CIcmp object is performed. int Receive (LPSTR pIcmpBuffer, int IcmpBufferSize) Reads the socket associated with the CIcmp object and returns the number of bytes read, or SOCKET_ERROR, if an error occurs. pIcmpBuffer is the address of the buffer to store the incoming message and IcmpBufferSize is the integer buffer size. The buffer must be large enough to contain the incoming message. In the case of an ICMP Echo Reply, the size would be the size of the outgoing message plus the size of an ICMP header plus the size of an IP header. Sets icmpRcvLen to the length of the message received, icmpPingReceivedAt to the time the receive command is issued, icmpRoundTripTime to the difference between icmpPingSentAt and icmpPingReceivedAt, icmpCurSeq to the incoming sequence number and icmpCurId to the incoming id field. Sets rcvSockAddr fields appropriately. Sets icmpSocketError and icmpSocketErrorMod to indicate the type of error, and returns the integer result of the operation. icmpSocketError and icmpSocketErrorMod are preserved until the next operation on this CIcmp object is performed. void DisplayError (CString ErrorType, CString FunctionName) Displays the provided ErrorType message prior to the decoded error message in icmpSocketError and icmpSocketErrorMod. Sets the message box title to FunctionName. The message is displayed in a modal box, requiring an OK response before the thread containing this method can progress.
The CIcmp class contains the following public variables:
icmpCurId icmpCurSeq icmpHops icmpHostAddress icmpMaxHops icmpPingReceivedAt icmpPingSentAt icmpRcvLen icmpRoundTripTime icmpSockAddr icmpSocket icmpPingTimer icmpSocketError icmpSocketErrorMod pIcmpHeader pIpHeader rcvSockAddr
To use this class,
EWDPing - демонстрирует использование класса CIcmp
EWDPing is a sample program which illustrates the use of the CIcmp class. This program implements the ICMP Echo Request message (commonly known as PING) to check the on-line status of an Internet host, and uses TTL to trace the route to an Internet host. The .zip file contains the source for EWDPing as well as the source for the other custom classes used in the project: The program also makes use of a system timer to prevent "hanging" on a non-responsive gateway. Documentation for the methods and variables are provided within the .zip file. Скачать Демо программку - 151KB |