static public IReadOnlyList <PcapInterface> GetAllPcapInterfaces(string source, RemoteAuthentication credentials)
{
var devicePtr = IntPtr.Zero;
var errorBuffer = new StringBuilder(Pcap.PCAP_ERRBUF_SIZE);
var auth = RemoteAuthentication.CreateAuth(credentials);
try
{
var result = LibPcapSafeNativeMethods.pcap_findalldevs_ex(source, ref auth, ref devicePtr, errorBuffer);
if (result < 0)
{
throw new PcapException(errorBuffer.ToString());
}
}
catch (TypeLoadException ex)
{
throw new PlatformNotSupportedException(
"Operation is not supported on this platform.",
ex
);
}
var pcapInterfaces = GetAllPcapInterfaces(devicePtr, credentials);
// Free unmanaged memory allocation
LibPcapSafeNativeMethods.pcap_freealldevs(devicePtr);
return(pcapInterfaces);
}
/// <summary>
/// Open the device. To start capturing call the 'StartCapture' function
/// </summary>
/// <param name="configuration">
/// A <see cref="DeviceConfiguration"/>
/// </param>
public override void Open(DeviceConfiguration configuration)
{
var credentials = configuration.Credentials ?? Interface.Credentials;
var mode = configuration.Mode;
if (!Opened)
{
StringBuilder errbuf = new StringBuilder(Pcap.PCAP_ERRBUF_SIZE); //will hold errors
// set the StopCaptureTimeout value to twice the read timeout to ensure that
// we wait long enough before considering the capture thread to be stuck when stopping
// a background capture via StopCapture()
//
// NOTE: Doesn't affect Mono if unix poll is available, doesn't affect Linux because
// Linux devices have no timeout, they always block. Only affects Windows devices.
StopCaptureTimeout = new TimeSpan(0, 0, 0, 0, configuration.ReadTimeout * 2);
// modes other than OpenFlags.Promiscuous require pcap_open()
var otherModes = mode & ~DeviceModes.Promiscuous;
if ((credentials == null) || ((short)otherModes != 0) || (configuration.TimestampResolution != null))
{
PcapHandle = LibPcapSafeNativeMethods.pcap_create(
Name, // name of the device
errbuf); // error buffer
Configure(
configuration, nameof(configuration.Snaplen),
LibPcapSafeNativeMethods.pcap_set_snaplen, configuration.Snaplen
);
Configure(
configuration, "Promiscuous",
LibPcapSafeNativeMethods.pcap_set_promisc, (int)(mode & DeviceModes.Promiscuous)
);
Configure(
configuration, nameof(configuration.ReadTimeout),
LibPcapSafeNativeMethods.pcap_set_timeout, configuration.ReadTimeout
);
if (configuration.TimestampResolution.HasValue)
{
Configure(
configuration, nameof(configuration.TimestampResolution),
LibPcapSafeNativeMethods.pcap_set_tstamp_precision, (int)configuration.TimestampResolution
);
}
if (configuration.TimestampType.HasValue)
{
Configure(
configuration, nameof(configuration.TimestampType),
LibPcapSafeNativeMethods.pcap_set_tstamp_type, (int)configuration.TimestampType
);
}
}
else
{
// We got authentication, so this is an rpcap device
var auth = RemoteAuthentication.CreateAuth(credentials);
PcapHandle = LibPcapSafeNativeMethods.pcap_open(
Name, // name of the device
configuration.Snaplen, // portion of the packet to capture.
(short)mode, // flags
(short)configuration.ReadTimeout, // read timeout
ref auth, // authentication
errbuf); // error buffer
}
if (PcapHandle == IntPtr.Zero)
{
string err = "Unable to open the adapter (" + Name + "). " + errbuf.ToString();
throw new PcapException(err);
}
Configure(
configuration, nameof(configuration.Monitor),
LibPcapSafeNativeMethods.pcap_set_rfmon, (int?)configuration.Monitor
);
Configure(
configuration, nameof(configuration.BufferSize),
LibPcapSafeNativeMethods.pcap_set_buffer_size, configuration.BufferSize
);
// Check if immediate is supported
var immediate_supported = Pcap.LibpcapVersion >= new Version(1, 5, 0);
// Check if we can do immediate by setting mintocopy to 0
// See https://www.tcpdump.org/manpages/pcap_set_immediate_mode.3pcap.html
var mintocopy_supported = RuntimeInformation.IsOSPlatform(OSPlatform.Windows);
if (configuration.Immediate.HasValue)
{
if (!immediate_supported && !mintocopy_supported)
{
configuration.RaiseConfigurationFailed(
nameof(configuration.Immediate),
(int)PcapError.PlatformNotSupported
);
}
else if (immediate_supported)
{
var immediate = configuration.Immediate.Value ? 1 : 0;
Configure(
configuration, nameof(configuration.Immediate),
LibPcapSafeNativeMethods.pcap_set_immediate_mode, immediate
);
}
}
var activationResult = LibPcapSafeNativeMethods.pcap_activate(PcapHandle);
if (activationResult < 0)
{
string err = "Unable to activate the adapter (" + Name + "). Return code: " + activationResult.ToString();
throw new PcapException(err);
}
Active = true;
// retrieve the file descriptor of the adapter for use with poll()
if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
{
FileDescriptor = LibPcapSafeNativeMethods.pcap_get_selectable_fd(PcapHandle);
}
// Below configurations must be done after the device gets activated
Configure(
configuration, nameof(configuration.KernelBufferSize),
LibPcapSafeNativeMethods.pcap_setbuff, configuration.KernelBufferSize
);
if (configuration.Immediate == true && mintocopy_supported && !immediate_supported)
{
Configure(
configuration, nameof(configuration.Immediate),
LibPcapSafeNativeMethods.pcap_setmintocopy, 0
);
}
Configure(
configuration, nameof(configuration.MinToCopy),
LibPcapSafeNativeMethods.pcap_setmintocopy, configuration.MinToCopy
);
}
}
/// <summary>
/// Open the device. To start capturing call the 'StartCapture' function
/// </summary>
/// <param name="configuration">
/// A <see cref="DeviceConfiguration"/>
/// </param>
public override void Open(DeviceConfiguration configuration)
{
if (Opened)
{
return;
}
var credentials = configuration.Credentials ?? Interface.Credentials;
var mode = configuration.Mode;
// Check if immediate is supported
var immediate_supported = Pcap.LibpcapVersion >= new Version(1, 5, 0);
// Check if we can do immediate by setting mintocopy to 0
// See https://www.tcpdump.org/manpages/pcap_set_immediate_mode.3pcap.html
var mintocopy_supported = RuntimeInformation.IsOSPlatform(OSPlatform.Windows);
var errbuf = new StringBuilder(Pcap.PCAP_ERRBUF_SIZE); //will hold errors
// set the StopCaptureTimeout value to twice the read timeout to ensure that
// we wait long enough before considering the capture thread to be stuck when stopping
// a background capture via StopCapture()
//
// NOTE: Doesn't affect Mono if unix poll is available, doesn't affect Linux because
// Linux devices have no timeout, they always block. Only affects Windows devices.
StopCaptureTimeout = new TimeSpan(0, 0, 0, 0, configuration.ReadTimeout * 2);
// modes other than OpenFlags.Promiscuous require pcap_open()
var otherModes = mode & ~DeviceModes.Promiscuous;
if (immediate_supported || mintocopy_supported)
{
// We can do MaxResponsiveness through Immediate mode
otherModes &= ~DeviceModes.MaxResponsiveness;
}
var immediateMode = configuration.Immediate;
if (mode.HasFlag(DeviceModes.MaxResponsiveness))
{
immediateMode = true;
}
// Some configurations can only be used with pcap_create
var use_pcap_create = credentials == null && (short)otherModes == 0;
if (use_pcap_create)
{
Handle = LibPcapSafeNativeMethods.pcap_create(
Name, // name of the device
errbuf); // error buffer
// Those are configurations that pcap_open can handle differently
Configure(
configuration, nameof(configuration.Snaplen),
LibPcapSafeNativeMethods.pcap_set_snaplen, configuration.Snaplen
);
Configure(
configuration, "Promiscuous",
LibPcapSafeNativeMethods.pcap_set_promisc, (int)(mode & DeviceModes.Promiscuous)
);
Configure(
configuration, nameof(configuration.ReadTimeout),
LibPcapSafeNativeMethods.pcap_set_timeout, configuration.ReadTimeout
);
}
else
{
// We got authentication, so this is an rpcap device
var auth = RemoteAuthentication.CreateAuth(credentials);
// Immediate and MaxResponsiveness are the same thing
if (immediateMode == true)
{
mode |= DeviceModes.MaxResponsiveness;
}
// No need to worry about it anymore
immediateMode = null;
try
{
Handle = LibPcapSafeNativeMethods.pcap_open(
Name, // name of the device
configuration.Snaplen, // portion of the packet to capture.
(short)mode, // flags
(short)configuration.ReadTimeout, // read timeout
ref auth, // authentication
errbuf); // error buffer
}
catch (TypeLoadException)
{
var reason = credentials != null ? "Remote PCAP" : "Requested DeviceModes";
var err = $"Unable to open the adapter '{Name}'. {reason} not supported";
throw new PcapException(err, PcapError.PlatformNotSupported);
}
}
if (Handle.IsInvalid)
{
var err = $"Unable to open the adapter '{Name}'. {errbuf}";
throw new PcapException(err);
}
ConfigureIfCompatible(use_pcap_create,
configuration, nameof(configuration.TimestampResolution),
LibPcapSafeNativeMethods.pcap_set_tstamp_precision, (int?)configuration.TimestampResolution
);
ConfigureIfCompatible(use_pcap_create,
configuration, nameof(configuration.TimestampType),
LibPcapSafeNativeMethods.pcap_set_tstamp_type, (int?)configuration.TimestampType
);
ConfigureIfCompatible(use_pcap_create,
configuration, nameof(configuration.Monitor),
LibPcapSafeNativeMethods.pcap_set_rfmon, (int?)configuration.Monitor
);
ConfigureIfCompatible(use_pcap_create,
configuration, nameof(configuration.BufferSize),
LibPcapSafeNativeMethods.pcap_set_buffer_size, configuration.BufferSize
);
if (immediateMode.HasValue)
{
if (!immediate_supported && !mintocopy_supported)
{
configuration.RaiseConfigurationFailed(
nameof(configuration.Immediate),
PcapError.PlatformNotSupported,
"Immediate mode not available"
);
}
else if (immediate_supported)
{
var immediate = immediateMode.Value ? 1 : 0;
Configure(
configuration, nameof(configuration.Immediate),
LibPcapSafeNativeMethods.pcap_set_immediate_mode, immediate
);
}
}
// pcap_open returns an already activated device
if (use_pcap_create)
{
var activationResult = LibPcapSafeNativeMethods.pcap_activate(Handle);
if (activationResult < 0)
{
string err = "Unable to activate the adapter (" + Name + ").";
throw new PcapException(err, activationResult);
}
}
base.Open(configuration);
// retrieve the file descriptor of the adapter for use with poll()
if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
{
FileDescriptor = LibPcapSafeNativeMethods.pcap_get_selectable_fd(Handle);
}
// Below configurations must be done after the device gets activated
Configure(
configuration, nameof(configuration.KernelBufferSize),
LibPcapSafeNativeMethods.pcap_setbuff, configuration.KernelBufferSize
);
if (immediateMode == true && mintocopy_supported && !immediate_supported)
{
Configure(
configuration, nameof(configuration.Immediate),
LibPcapSafeNativeMethods.pcap_setmintocopy, 0
);
}
Configure(
configuration, nameof(configuration.MinToCopy),
LibPcapSafeNativeMethods.pcap_setmintocopy, configuration.MinToCopy
);
}
/// <summary>
/// Open the device. To start capturing call the 'StartCapture' function
/// </summary>
/// <param name="mode">
/// A <see cref="DeviceMode"/>
/// </param>
/// <param name="read_timeout">
/// A <see cref="int"/>
/// </param>
/// <param name="monitor_mode">
/// A <see cref="MonitorMode"/>
/// </param>
/// <param name="kernel_buffer_size">
/// A <see cref="uint"/>
/// </param>
public override void Open(DeviceMode mode, int read_timeout, MonitorMode monitor_mode, uint kernel_buffer_size)
{
if (!Opened)
{
StringBuilder errbuf = new StringBuilder(Pcap.PCAP_ERRBUF_SIZE); //will hold errors
// set the StopCaptureTimeout value to twice the read timeout to ensure that
// we wait long enough before considering the capture thread to be stuck when stopping
// a background capture via StopCapture()
//
// NOTE: Doesn't affect Mono if unix poll is available, doesn't affect Linux because
// Linux devices have no timeout, they always block. Only affects Windows devices.
StopCaptureTimeout = new TimeSpan(0, 0, 0, 0, read_timeout * 2);
if (Interface.Credentials == null)
{
PcapHandle = LibPcapSafeNativeMethods.pcap_create(
Name, // name of the device
errbuf); // error buffer
}
else
{
// We got authentication, so this is an rpcap device
var auth = RemoteAuthentication.CreateAuth(Name, Interface.Credentials);
PcapHandle = LibPcapSafeNativeMethods.pcap_open
(Name, // name of the device
Pcap.MAX_PACKET_SIZE, // portion of the packet to capture.
// MAX_PACKET_SIZE (65536) grants that the whole packet will be captured on all the MACs.
(short)0, // No flags here
(short)read_timeout, // read timeout
ref auth, // authentication
errbuf); // error buffer
}
if (PcapHandle == IntPtr.Zero)
{
string err = "Unable to open the adapter (" + Name + "). " + errbuf.ToString();
throw new PcapException(err);
}
LibPcapSafeNativeMethods.pcap_set_snaplen(PcapHandle, Pcap.MAX_PACKET_SIZE);
if (monitor_mode == MonitorMode.Active)
{
try
{
LibPcapSafeNativeMethods.pcap_set_rfmon(PcapHandle, (int)monitor_mode);
}
catch (EntryPointNotFoundException)
{
throw new PcapException("This implementation of libpcap does not support monitor mode.");
}
}
LibPcapSafeNativeMethods.pcap_set_promisc(PcapHandle, (int)mode);
LibPcapSafeNativeMethods.pcap_set_timeout(PcapHandle, read_timeout);
if (kernel_buffer_size != 0)
{
KernelBufferSize = kernel_buffer_size;
}
var activationResult = LibPcapSafeNativeMethods.pcap_activate(PcapHandle);
if (activationResult < 0)
{
string err = "Unable to activate the adapter (" + Name + "). Return code: " + activationResult.ToString();
throw new PcapException(err);
}
Active = true;
// retrieve the file descriptor of the adapter for use with poll()
if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
{
FileDescriptor = LibPcapSafeNativeMethods.pcap_get_selectable_fd(PcapHandle);
}
}
}
