/// <summary>
/// Initializes a new instance of the <see cref="SnmpPDU"/> struct with decoupling the reference of varBinds
/// </summary>
/// <param name="pduType">Type of the pdu.</param>
/// <param name="requestId">The request identifier.</param>
/// <param name="errorStatus">The error status.</param>
/// <param name="errorIndex">Index of the error.</param>
/// <param name="varBinds">The variable binds.</param>
public SnmpPDU(PduType pduType, int requestId, SnmpErrorStatus errorStatus, int errorIndex, VarBind[] varBinds)
{
PduType = pduType;
RequestId = requestId;
ErrorStatus = errorStatus;
ErrorIndex = errorIndex;
VarBinds = new ReadOnlyCollection <VarBind>((VarBind[])varBinds.Clone());
}
/// <summary>
/// Initializes a new instance of the <see cref="SnmpV2cPDU"/> struct without decoupling refrence for varbinds.
/// </summary>
/// <param name="pduType">Type of the pdu.</param>
/// <param name="varBinds">The variable binds.</param>
/// <param name="requestId">The request identifier.</param>
/// <param name="errorStatus">The error status.</param>
/// <param name="errorIndex">Index of the error.</param>
internal SnmpV2cPDU(PduType pduType, VarBind[] varBinds, int requestId, SnmpErrorStatus errorStatus, int errorIndex)
{
PduType = pduType;
VarBinds = new ReadOnlyCollection<VarBind>(varBinds);
RequestId = requestId;
ErrorStatus = errorStatus;
ErrorIndex = errorIndex;
}
/// <summary>
/// Initializes a new instance of the <see cref="SnmpPDU"/> struct without decoupling refrence for varbinds.
/// </summary>
/// <param name="pduType">Type of the pdu.</param>
/// <param name="varBinds">The variable binds.</param>
/// <param name="requestId">The request identifier.</param>
/// <param name="errorStatus">The error status.</param>
/// <param name="errorIndex">Index of the error.</param>
internal SnmpPDU(PduType pduType, VarBind[] varBinds, int requestId, SnmpErrorStatus errorStatus, int errorIndex)
{
PduType = pduType;
VarBinds = new ReadOnlyCollection <VarBind>(varBinds);
RequestId = requestId;
ErrorStatus = errorStatus;
ErrorIndex = errorIndex;
}
/// <summary>
/// Initializes a new instance of the <see cref="SnmpV2cPDU"/> struct with decoupling the reference of varBinds
/// </summary>
/// <param name="pduType">Type of the pdu.</param>
/// <param name="requestId">The request identifier.</param>
/// <param name="errorStatus">The error status.</param>
/// <param name="errorIndex">Index of the error.</param>
/// <param name="varBinds">The variable binds.</param>
public SnmpV2cPDU(PduType pduType, int requestId, SnmpErrorStatus errorStatus, int errorIndex, VarBind[] varBinds)
{
PduType = pduType;
RequestId = requestId;
ErrorStatus = errorStatus;
ErrorIndex = errorIndex;
VarBinds = new ReadOnlyCollection<VarBind>((VarBind[])varBinds.Clone());
}
/// <summary>
/// Converts the Asn.1 encoded byte array to SNMP Datagram.
/// </summary>
/// <param name="bytes">The asn.1 encoded bytes.</param>
/// <returns>
/// SnmpPacket
/// </returns>
/// <exception cref="System.ArgumentNullException">bytes</exception>
/// <exception cref="System.IO.InvalidDataException">Snmp Version V3 not supported</exception>
/// <exception cref="System.NotImplementedException">SNMP v1 traps are not yet implemented</exception>
public static SnmpDatagram ToSnmpDatagram(this byte[] bytes)
{
if (bytes == null || bytes.Length == 0)
{
throw new ArgumentNullException("bytes");
}
int offset = 0;
int length;
offset = bytes.NextValueLength(offset, -1, -1, -1, out length);
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.Integer, out length);
SnmpVersion snmpVersion = (SnmpVersion)bytes.ReadInteger(offset, length);
offset += length;
if (snmpVersion == SnmpVersion.V3)
{
throw new InvalidDataException("Snmp Version V3 not supported");
}
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.OctetString, out length);
string community = bytes.ReadOctetString(offset, length);
offset += length;
PduType pduType = (PduType)(bytes[offset++] & 0x1F);
if (pduType == PduType.Trap)
{
throw new NotImplementedException("SNMP v1 traps are not yet implemented");
}
offset = bytes.ReadLength(offset, out length);
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.Integer, out length);
int requestId = bytes.ReadInteger(offset, length);
offset += length;
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.Integer, out length);
SnmpErrorStatus errorStatus = (SnmpErrorStatus)bytes.ReadInteger(offset, length);
offset += length;
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.Integer, out length);
int errorIndex = bytes.ReadInteger(offset, length);
offset += length;
offset = bytes.NextValueLength(offset, (int)Asn1Class.Universal, (int)ConstructType.Constructed, (int)Asn1Tag.Sequence, out length);
VarBind[] varBinds = bytes.ReadVarBinds(offset, length);
return(new SnmpDatagram(new SnmpHeader(snmpVersion, community), new SnmpPDU(pduType, varBinds, requestId, errorStatus, errorIndex)));
}
/// <summary>
/// Initializes a new instance of the <see cref="SnmpSimpleDatagram" /> class.
/// </summary>
/// <param name="snmpDatagramInput">The SNMP datagram input.</param>
public SnmpSimpleDatagram(SnmpDatagram snmpDatagramInput)
{
snmpDatagram = snmpDatagramInput;
Version = snmpDatagram.Header.Version;
Community = snmpDatagram.Header.Community;
PDUType = snmpDatagram.PduV2c.PduType;
RequestId = snmpDatagram.PduV2c.RequestId;
ErrorStatus = snmpDatagram.PduV2c.ErrorStatus;
ErrorIndex = snmpDatagram.PduV2c.ErrorIndex;
VarBinds = new List <KeyValuePair <string, object> >();
for (int i = 0; i < snmpDatagram.PduV2c.VarBinds.Count; i++)
{
var varBind = snmpDatagram.PduV2c.VarBinds[i];
VarBinds.Add(new KeyValuePair <string, object>(varBind.Oid.ToString(), varBind.Value));
}
}
public SnmpDatagramV2C(
DateTimeOffset receivedTime,
string sourceIpAddress,
SnmpHeader header,
IReadOnlyList <VarBind> varBinds,
PduType pduType,
int requestId,
SnmpErrorStatus errorStatus,
int errorIndex)
: base(receivedTime, sourceIpAddress, header, varBinds)
{
this.PduType = pduType;
this.RequestId = requestId;
this.ErrorStatus = errorStatus;
this.ErrorIndex = errorIndex;
}
// returns offset of varbind list
public UInt32 Deserialize(Byte[] packet, UInt32 offset)
{
this.packetBytes = packet;
UInt32 initialOffset = offset;
//
// SNMP Message Type
//
if (packet[offset] != Asn1.TYPE_SEQUENCE)
{
throw new FormatException(String.Format(
"Expected snmp packet to be of type Sequence but is {0}", Asn1.GetTypeOrNumberString(packet[offset])));
}
offset++;
UInt32 sequenceLength = Asn1.ParseDefiniteLength(packet, ref offset);
UInt32 sequenceOffsetLimit = offset + sequenceLength;
if (packet.Length - offset < sequenceLength)
{
throw new FormatException(String.Format(
"Failed to parse snmp packet because it was truncated from {0} bytes to {1}",
sequenceLength + (offset - initialOffset), packet.Length - initialOffset));
}
//
// Version
//
if (packet[offset] != Asn1.TYPE_INTEGER)
{
throw new FormatException(String.Format(
"Expected snmp version to be of type Integer but is {0}", Asn1.GetTypeOrNumberString(packet[offset])));
}
offset++;
this.version = Asn1.ParseIntegerToByte(packet, ref offset);
if (this.version != 0)
{
throw new NotImplementedException(String.Format("Snmp version {0} (binary code {1}) is not implemented yet",
this.version + 1, this.version));
}
//
// Community
//
if (packet[offset] != Asn1.TYPE_OCTET_STRING)
{
throw new FormatException(String.Format(
"Expected snmp community to be of type OctetString but is '{0}'", Asn1.GetTypeOrNumberString(packet[offset])));
}
offset++;
Int32 communityLength = (Byte)Asn1.ParseDefiniteLength(packet, ref offset);
if (communityLength < 0)
{
throw new FormatException(String.Format("Expected community octet string length to be positive but is {0}", communityLength));
}
offset += (UInt32)communityLength;
//
// PDU Type
//
Byte pduTypeByte = packet[offset];
offset++;
if (pduTypeByte < 0xA0)
{
throw new FormatException(String.Format("Expected SNMP pdu type to be >= 0xA0 but is {0:2X}", pduTypeByte));
}
//
// Use similar logic to parse similar types
// Get, GetNext, GetResponse, Set
if (pduTypeByte <= 0xA3)
{
SnmpPduType pduType = (SnmpPduType)(pduTypeByte - 0xA0);
UInt32 pduLength = Asn1.ParseDefiniteLength(packet, ref offset);
if (offset + pduLength != sequenceOffsetLimit)
{
throw new FormatException(String.Format(
"Snmp packet is malformed, the pdu which ends at {0} does not end at the same place as the sequence at {1}",
offset + pduLength, sequenceOffsetLimit));
}
//
// Request ID
//
if (packet[offset] != Asn1.TYPE_INTEGER)
{
throw new FormatException(String.Format(
"Expected Snmp{0}Pdu to start with the Integer type but started with '{1}'", pduType, Asn1.GetTypeOrNumberString(packet[offset])));
}
offset++;
this.requestID = Asn1.ParseIntegerToInt32(packet, ref offset);
//
// Error Status
//
if (packet[offset] != Asn1.TYPE_INTEGER)
{
throw new FormatException(String.Format(
"Expected Snmp{0}Pdu ErrorStatus to be an Integer type but is '{1}'", pduType, Asn1.GetTypeOrNumberString(packet[offset])));
}
offset++;
this.errorStatus = (SnmpErrorStatus)Asn1.ParseIntegerToInt32(packet, ref offset);
//
// Error Index
//
if (packet[offset] != Asn1.TYPE_INTEGER)
{
throw new FormatException(String.Format(
"Expected Snmp{0}Pdu ErrorIndex to be an Integer type but is '{1}'", pduType, Asn1.GetTypeOrNumberString(packet[offset])));
}
offset++;
this.errorIndex = Asn1.ParseIntegerToInt32(packet, ref offset);
//
// Varbind List
//
if (packet[offset] != Asn1.TYPE_SEQUENCE)
{
throw new FormatException(String.Format(
"Expected varbind list to be of type Sequence but is {0}", Asn1.GetTypeOrNumberString(packet[offset])));
}
offset++;
UInt32 varbindListLength = Asn1.ParseDefiniteLength(packet, ref offset);
if (offset + varbindListLength != sequenceOffsetLimit)
{
throw new FormatException(String.Format(
"Snmp packet is malformed, the varbind list which ends at {0} does not end at the same place as the sequence at {1}",
offset + varbindListLength, sequenceOffsetLimit));
}
return(offset); // return the offset to the varbind variables
}
else
{
throw new NotImplementedException(String.Format("Snmp pdu type {0} is not implemented yet", pduTypeByte));
}
}
public SnmpDatagramV2C(
DateTimeOffset receivedTime,
string sourceIpAddress,
SnmpHeader header,
IReadOnlyList<VarBind> varBinds,
PduType pduType,
int requestId,
SnmpErrorStatus errorStatus,
int errorIndex)
: base(receivedTime, sourceIpAddress, header, varBinds)
{
this.PduType = pduType;
this.RequestId = requestId;
this.ErrorStatus = errorStatus;
this.ErrorIndex = errorIndex;
}
/// <summary>
/// Converts the Asn.1 encoded byte array to SNMP Datagram.
/// </summary>
/// <param name="byteSegment">The asn.1 encoded bytes.</param>
/// <param name="timestamp">The timestamp when the packet has been received.</param>
/// <param name="sourceIpAddress">The source IP address of the packet.</param>
/// <returns>
/// SnmpPacket
/// </returns>
/// <exception cref="System.ArgumentNullException">bytes</exception>
/// <exception cref="System.IO.InvalidDataException">Snmp Version V3 not supported</exception>
public static SnmpDatagram ToSnmpDatagram(
this ArraySegment <byte> byteSegment,
DateTimeOffset timestamp,
string sourceIpAddress)
{
var bytes = byteSegment.Array;
if (bytes == null || bytes.Length == 0)
{
throw new ArgumentNullException("byteSegment");
}
int offset = byteSegment.Offset;
int length;
offset = bytes.NextValueLength(offset, -1, -1, -1, out length);
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.Integer, out length);
SnmpVersion snmpVersion = (SnmpVersion)bytes.ReadInteger(offset, length);
offset += length;
if (snmpVersion == SnmpVersion.V3)
{
throw new InvalidDataException("Snmp Version V3 not supported");
}
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.OctetString, out length);
string community = bytes.ReadOctetString(offset, length);
offset += length;
PduType pduType = (PduType)(bytes[offset++] & 0x1F);
offset = bytes.ReadLength(offset, out length);
if (snmpVersion == SnmpVersion.V1 && pduType == PduType.Trap)
{
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.ObjectIdentifier, out length);
ObjectIdentifier oid = new ObjectIdentifier(bytes.ReadOids(offset, length));
offset += length;
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1SnmpTag.IpAddress, out length);
IPAddress ipAddress = bytes.ReadIpAddress(offset);
offset += length;
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.Integer, out length);
GenericTrap genericTrap = (GenericTrap)bytes.ReadInteger(offset, length);
offset += length;
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.Integer, out length);
int specificTrap = bytes.ReadInteger(offset, length);
offset += length;
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1SnmpTag.TimeTicks, out length);
uint timeStamp = bytes.ReadUnsignedInteger(offset, length);
offset += length;
offset = bytes.NextValueLength(offset, (int)Asn1Class.Universal, (int)ConstructType.Constructed, (int)Asn1Tag.Sequence, out length);
VarBind[] varBinds = bytes.ReadVarBinds(offset, length);
return(new SnmpDatagramV1(
timestamp,
sourceIpAddress,
new SnmpHeader(snmpVersion, community),
varBinds));
}
else
{
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.Integer, out length);
int requestId = bytes.ReadInteger(offset, length);
offset += length;
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.Integer, out length);
SnmpErrorStatus errorStatus = (SnmpErrorStatus)bytes.ReadInteger(offset, length);
offset += length;
offset = bytes.NextValueLength(offset, -1, -1, (int)Asn1Tag.Integer, out length);
int errorIndex = bytes.ReadInteger(offset, length);
offset += length;
offset = bytes.NextValueLength(offset, (int)Asn1Class.Universal, (int)ConstructType.Constructed, (int)Asn1Tag.Sequence, out length);
VarBind[] varBinds = bytes.ReadVarBinds(offset, length);
return(new SnmpDatagramV2C(
timestamp,
sourceIpAddress,
new SnmpHeader(snmpVersion, community),
varBinds,
pduType,
requestId,
errorStatus,
errorIndex));
}
}
/// <summary>
/// Initializes a new instance of the <see cref="SnmpDatagram"/> class.
/// </summary>
/// <param name="pduType">Type of the pdu.</param>
/// <param name="snmpVersion">The SNMP version.</param>
/// <param name="community">The community.</param>
/// <param name="requestId">The request identifier.</param>
/// <param name="errorStatus">The error status.</param>
/// <param name="errorIndex">Index of the error.</param>
/// <param name="varBinds">The variable binds.</param>
public SnmpDatagram(PduType pduType, SnmpVersion snmpVersion, string community, int requestId, SnmpErrorStatus errorStatus, int errorIndex, VarBind[] varBinds)
{
Header = new SnmpHeader(snmpVersion, community);
PDU = new SnmpPDU(pduType, requestId, errorStatus, errorIndex, varBinds);
}
/// <summary>
/// Initializes a new instance of the <see cref="SnmpSimpleDatagram" /> class.
/// </summary>
/// <param name="snmpDatagramInput">The SNMP datagram input.</param>
public SnmpSimpleDatagram(SnmpDatagram snmpDatagramInput)
{
snmpDatagram = snmpDatagramInput;
Version = snmpDatagram.Header.Version;
Community = snmpDatagram.Header.Community;
PDUType = snmpDatagram.PduV2c.PduType;
RequestId = snmpDatagram.PduV2c.RequestId;
ErrorStatus = snmpDatagram.PduV2c.ErrorStatus;
ErrorIndex = snmpDatagram.PduV2c.ErrorIndex;
VarBinds = new List<KeyValuePair<string, object>>();
for(int i=0 ; i< snmpDatagram.PduV2c.VarBinds.Count; i++)
{
var varBind = snmpDatagram.PduV2c.VarBinds[i];
VarBinds.Add(new KeyValuePair<string, object>(varBind.Oid.ToString(), varBind.Value));
}
}
/// <summary>
/// Initializes a new instance of the <see cref="SnmpDatagram"/> class.
/// </summary>
/// <param name="pduType">Type of the pdu.</param>
/// <param name="snmpVersion">The SNMP version.</param>
/// <param name="community">The community.</param>
/// <param name="requestId">The request identifier.</param>
/// <param name="errorStatus">The error status.</param>
/// <param name="errorIndex">Index of the error.</param>
/// <param name="varBinds">The variable binds.</param>
public SnmpDatagram(PduType pduType, SnmpVersion snmpVersion, string community, int requestId, SnmpErrorStatus errorStatus, int errorIndex, VarBind[] varBinds)
{
Header = new SnmpHeader(snmpVersion, community);
PduV2c = new SnmpV2cPDU(pduType, requestId, errorStatus, errorIndex, varBinds);
PduV1 = default(SnmpV1PDU);
}
