Module: SNMP::BER::Encode
- Included in:
- EndOfMibView, Integer, IpAddress, Message, NoSuchInstance, NoSuchObject, Null, ObjectId, OctetString, PDU, SNMPv1_Trap, VarBind, VarBindList
- Defined in:
- lib/snmp/ber.rb
Instance Method Summary collapse
-
#encode_exception(tag) ⇒ Object
Encode an exception.
-
#encode_integer(value) ⇒ Object
Encode integer.
-
#encode_length(length) ⇒ Object
Encode the length field for TLV data.
- #encode_null ⇒ Object
-
#encode_object_id(value) ⇒ Object
Encode an object id.
-
#encode_octet_string(value) ⇒ Object
Wrap string in a octet string tag and length.
-
#encode_sequence(value) ⇒ Object
Wrap value in a sequence tag and length.
- #encode_tagged_integer(tag, value) ⇒ Object
-
#encode_tlv(tag, value) ⇒ Object
Wraps value in a tag and length.
-
#integer_to_octets(i) ⇒ Object
Helper method for encoding integer-like things.
Instance Method Details
#encode_exception(tag) ⇒ Object
Encode an exception. The encoding is simply the exception tag with no data, similar to NULL.
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# File 'lib/snmp/ber.rb', line 302 def encode_exception(tag) tag.chr << "\000" end |
#encode_integer(value) ⇒ Object
Encode integer
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# File 'lib/snmp/ber.rb', line 259 def encode_integer(value) encode_tagged_integer(INTEGER_TAG, value) end |
#encode_length(length) ⇒ Object
Encode the length field for TLV data. Returns the length octets as a string.
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# File 'lib/snmp/ber.rb', line 246 def encode_length(length) raise InvalidLength, length.to_s if length < 0 if length < 0x80 length.chr else data = integer_to_octets(length) (data.size | 0x80).chr << data end end |
#encode_null ⇒ Object
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# File 'lib/snmp/ber.rb', line 294 def encode_null NULL_TAG.chr << "\000" end |
#encode_object_id(value) ⇒ Object
Encode an object id. The input is assumed to be an array of integers representing the object id.
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# File 'lib/snmp/ber.rb', line 334 def encode_object_id(value) raise InvalidObjectId, value.to_s if value.length < 1 raise InvalidObjectId, value.to_s if value[0] > 2 data = "".dup if (value.length > 1) raise InvalidObjectId if value[0] < 2 && value[1] > 40 data << (40 * value[0] + value[1]).chr for i in 2...value.length if value[i] < 0x80 data << value[i].chr else octets = "" n = value[i] begin octets = (n & 0x7f | 0x80).chr << octets n = n >> 7 end until n == 0 octets[-1] = (octets[-1].ord & 0x7f).chr data << octets end end elsif (value.length == 1) data << (40 * value[0]).chr end encode_tlv(OBJECT_IDENTIFIER_TAG, data) end |
#encode_octet_string(value) ⇒ Object
Wrap string in a octet string tag and length.
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# File 'lib/snmp/ber.rb', line 319 def encode_octet_string(value) encode_tlv(OCTET_STRING_TAG, value) end |
#encode_sequence(value) ⇒ Object
Wrap value in a sequence tag and length.
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# File 'lib/snmp/ber.rb', line 326 def encode_sequence(value) encode_tlv(SEQUENCE_TAG, value) end |
#encode_tagged_integer(tag, value) ⇒ Object
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# File 'lib/snmp/ber.rb', line 263 def encode_tagged_integer(tag, value) if value > 0 && value < 0x80 data = value.chr else data = integer_to_octets(value) if value > 0 && data[0].ord > 0x7f data = "\000".dup << data elsif value < 0 && data[0].ord < 0x80 data = "\377".dup << data end end encode_tlv(tag, data) end |
#encode_tlv(tag, value) ⇒ Object
Wraps value in a tag and length. This method expects an integer tag and a string value.
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# File 'lib/snmp/ber.rb', line 310 def encode_tlv(tag, value) data = tag.chr << encode_length(value.length) data = data << value if value.length > 0 data end |
#integer_to_octets(i) ⇒ Object
Helper method for encoding integer-like things.
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# File 'lib/snmp/ber.rb', line 280 def integer_to_octets(i) if i >= 0 done = 0 else done = -1 end octets = "" begin octets = (i & 0xff).chr << octets i = i >> 8 end until i == done octets end |