The WSAEnumProtocols
function is used to discover information about the collection of
transport protocols and protocol chains installed on the local computer.
Since layered protocols are only usable by applications when installed
in protocol chains, information on layered protocols is not included in lpProtocolBuffer. The lpiProtocols parameter can be used as a filter to
constrain the amount of information provided. Often, lpiProtocols will
be specified as a NULL pointer that will cause the function to return
information on all available transport protocols and protocol chains.
A WSAPROTOCOL_INFO structure is provided in the buffer pointed to by
lpProtocolBuffer for each requested protocol. If the specified buffer is
not large enough (as indicated by the input value of lpdwBufferLength ),
the value pointed to by lpdwBufferLength will be updated to indicate the
required buffer size. The application should then obtain a large enough
buffer and call WSAEnumProtocols again.
The order in which the WSAPROTOCOL_INFO structures appear in the buffer
coincides with the order in which the protocol entries were registered
by the service provider using the WS2_32.DLL, or with any subsequent
reordering that occurred through the Windows Sockets application or DLL
supplied for establishing default TCP/IP providers.
This demo returns the names of the installed protocols
into List1, and other WSAPROTOCOL_INFO in List2 and List3.
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Option Explicit
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' Copyright ©1996-2011 VBnet/Randy Birch, All Rights Reserved.
' Some pages may also contain other copyrights by the author.
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' Distribution: You can freely use this code in your own
' applications, but you may not reproduce
' or publish this code on any web site,
' online service, or distribute as source
' on any media without express permission.
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Private Const MAX_PROTOCOL_CHAIN As Long = 7
Private Const IP_SUCCESS As Long = 0
Private Const MAX_WSADescription As Long = 256
Private Const MAX_WSASYSStatus As Long = 128
Private Const WSAPROTOCOL_LEN As Long = 255
Private Const WS_VERSION_REQD As Long = &H101
Private Const XP1_CONNECTIONLESS As Long = &H1
Private Const XP1_GUARANTEED_DELIVERY As Long = &H2
Private Const XP1_GUARANTEED_ORDER As Long = &H4
Private Const XP1_MESSAGE_ORIENTED As Long = &H8
Private Const XP1_PSEUDO_STREAM As Long = &H10
Private Const XP1_GRACEFUL_CLOSE As Long = &H20
Private Const XP1_EXPEDITED_DATA As Long = &H40
Private Const XP1_CONNECT_DATA As Long = &H80
Private Const XP1_DISCONNECT_DATA As Long = &H100
Private Const XP1_SUPPORT_BROADCAST As Long = &H200
Private Const XP1_SUPPORT_MULTIPOINT As Long = &H400
Private Const XP1_MULTIPOINT_CONTROL_PLANE As Long = &H800
Private Const XP1_MULTIPOINT_DATA_PLANE As Long = &H1000
Private Const XP1_QOS_SUPPORTED As Long = &H2000
Private Const XP1_INTERRUPT As Long = &H4000
Private Const XP1_UNI_SEND As Long = &H8000
Private Const XP1_UNI_RECV As Long = &H10000
Private Const XP1_IFS_HANDLES As Long = &H20000
Private Const XP1_PARTIAL_MESSAGE As Long = &H40000
Private Type WSAPROTOCOLCHAIN
ChainLen As Long '/* the length of the chain, */
'/* length = 0 means layered protocol, */
'/* length = 1 means base protocol, */
'/* length > 1 means protocol chain */
ChainEntries(0 To MAX_PROTOCOL_CHAIN - 1) As Long '/* a list ofdwCatalogEntryIds */
End Type
Private Type GUID
Data1 As Long
Data2 As Integer
Data3 As Integer
Data4(0 To 7) As Byte
End Type
Private Type WSAPROTOCOL_INFO
dwServiceFlags1 As Long
dwServiceFlags2 As Long
dwServiceFlags3 As Long
dwServiceFlags4 As Long
dwProviderFlags As Long
ProviderId As GUID
dwCatalogEntryId As Long
ProtocolChain As WSAPROTOCOLCHAIN
iVersion As Integer
iAddressFamily As Long
iMaxSockAddr As Long
iMinSockAddr As Long
iSocketType As Long
iProtocol As Long
iProtocolMaxOffset As Long
iNetworkByteOrder As Long
iSecurityScheme As Long
dwMessageSize As Long
dwProviderReserved As Long
szProtocol(0 To WSAPROTOCOL_LEN) As Byte
End Type
Private Type WSADATA
wVersion As Integer
wHighVersion As Integer
szDescription(0 To MAX_WSADescription) As Byte
szSystemStatus(0 To MAX_WSASYSStatus) As Byte
wMaxSockets As Integer
wMaxUDPDG As Integer
dwVendorInfo As Long
End Type
Private Declare Function WSAStartup Lib "WSOCK32" _
(ByVal wVersionRequired As Long, _
lpWSADATA As WSADATA) As Long
Private Declare Function WSACleanup Lib "WSOCK32" () As Long
Private Declare Function WSAEnumProtocols Lib "ws2_32.dll" _
Alias "WSAEnumProtocolsA" _
(ByVal lpiProtocols As Long, _
lpProtocolBuffer As Any, _
lpdwBufferLength As Long) As Long
Private Declare Function StringFromGUID2 Lib "ole32.dll" _
(lpGuid As GUID, _
ByVal lpszOut As String, _
ByVal cchMax As Long) As Long
Private Sub Form_Load()
Command1.Caption = "WSAEnumProtocols"
End Sub
Private Sub Command1_Click()
Dim cbBuff As Long
Dim numEntries As Long
Dim lpBuff() As WSAPROTOCOL_INFO
Dim ret As Long
Dim n As Long
Const WSABASEERR = 10000
Const WSAENOBUFS = WSABASEERR + 55
'initialize Ws2_32.dll
If SocketsInitialize() Then
List1.Clear
'create a buffer too small for the call
ReDim lpBuff(0) As WSAPROTOCOL_INFO
ret = WSAEnumProtocols(0&, lpBuff(0), cbBuff)
'the error indicates the buffer passed
'was insufficient, and cbBuffs specifies
'the size of the buffer required to retrieve
'all data
If ret = -1 And Err.LastDllError = WSAENOBUFS Then
'number of entries is buffer divided
'by size of one WSAPROTOCOL_INFO type
numEntries = (cbBuff) \ LenB(lpBuff(0))
'dimension to 0-base
ReDim lpBuff(0 To numEntries - 1) As WSAPROTOCOL_INFO
'and call again
If WSAEnumProtocols(0&, lpBuff(0), cbBuff) > 0 Then
'add the retrieved items to a listbox
For n = 0 To numEntries - 1
List1.AddItem StrConv(lpBuff(n).szProtocol, vbUnicode)
List1.ItemData(List1.NewIndex) = lpBuff(n).dwServiceFlags1
List2.AddItem lpBuff(n).iAddressFamily & vbTab & _
lpBuff(n).iMinSockAddr & vbTab & _
lpBuff(n).iMaxSockAddr & vbTab & _
lpBuff(n).iNetworkByteOrder & vbTab & _
lpBuff(n).iProtocol & vbTab & _
lpBuff(n).iProtocolMaxOffset & vbTab & _
lpBuff(n).iSecurityScheme & vbTab & _
lpBuff(n).iSocketType & vbTab & _
lpBuff(n).iVersion & vbTab & _
"&H" & Hex(lpBuff(n).dwMessageSize)
List3.AddItem ConvertGuidToString(lpBuff(n).ProviderId)
Next
End If 'WSAEnumProtocols
End If 'ret = -1
End If 'SocketsInitialize
SocketsCleanup
End Sub
Private Sub List1_Click()
Text1.Text = GetServiceFlagsDesc(List1.ItemData(List1.ListIndex))
List2.TopIndex = List1.TopIndex
List3.TopIndex = List1.TopIndex
List2.Selected(List1.ListIndex) = True
List3.Selected(List1.ListIndex) = True
End Sub
Private Function ConvertGuidToString(lpGuid As GUID) As String
Dim nChars As Long
Dim ret As Long
Dim sBuff As String
sBuff = Space$(80)
nChars = Len(sBuff)
ret = StringFromGUID2(lpGuid, sBuff, nChars)
If ret > 0 Then
ConvertGuidToString = Left$(StrConv(sBuff, vbFromUnicode), ret - 1)
End If
End Function
Private Function GetServiceFlagsDesc(ByVal flag As Long) As String
Dim s As String
Dim nl As String
nl = vbCrLf
If flag And XP1_CONNECTIONLESS Then s = "Provides connectionless (datagram) service" & nl
If flag And XP1_GUARANTEED_DELIVERY Then s = s & "Guarantees all data sent will reach intended destination" & nl
If flag And XP1_GUARANTEED_ORDER Then s = s & "Guarantees data only arrives in order sent" & nl
If flag And XP1_MESSAGE_ORIENTED Then s = s & "Honors message boundaries" & nl
If flag And XP1_PSEUDO_STREAM Then s = s & "Message-oriented; boundaries ignored for receipts" & nl
If flag And XP1_GRACEFUL_CLOSE Then s = s & "Supports two-phase (graceful) close" & nl
If flag And XP1_EXPEDITED_DATA Then s = s & "Supports expedited (urgent) data" & nl
If flag And XP1_CONNECT_DATA Then s = s & "Supports connect data" & nl
If flag And XP1_DISCONNECT_DATA Then s = s & "Supports disconnect data" & nl
If flag And XP1_SUPPORT_BROADCAST Then s = s & "Supports broadcast mechanism" & nl
If flag And XP1_SUPPORT_MULTIPOINT Then s = s & "Supports multipoint or multicast" & nl
If flag And XP1_MULTIPOINT_CONTROL_PLANE Then s = s & "Control plane rooted (= 1) or nonrooted (= 0)" & nl
If flag And XP1_MULTIPOINT_DATA_PLANE Then s = s & "Data plane is rooted (= 1) or nonrooted (= 0). " & nl
If flag And XP1_QOS_SUPPORTED Then s = s & "Supports quality of service requests" & nl
If flag And XP1_INTERRUPT Then s = s & "Bit is reserved" & nl
If flag And XP1_UNI_SEND Then s = s & "Unidirectional in send direction" & nl
If flag And XP1_UNI_RECV Then s = s & "Unidirectional in recv direction" & nl
If flag And XP1_IFS_HANDLES Then s = s & "Socket descriptors returned are OS Installable File System (IFS) handles" & nl
If flag And XP1_PARTIAL_MESSAGE Then s = s & "supported in WSASend and WSASendTo" & nl
GetServiceFlagsDesc = s
End Function
Public Function SocketsInitialize() As Boolean
Dim WSAD As WSADATA
SocketsInitialize = WSAStartup(WS_VERSION_REQD, WSAD) = IP_SUCCESS
End Function
Public Sub SocketsCleanup()
If WSACleanup() <> 0 Then
MsgBox "Windows Sockets error occurred in Cleanup.", vbExclamation
End If
End Sub |
