ruby-nsca/lib/nsca/packet.rb
2015-07-03 15:35:20 +02:00

100 lines
3.4 KiB
Ruby

module NSCA
class Packet
class CSC32CheckFailed <Exception
end
class VersionCheckFailed <Exception
end
def self.versions version = nil
@@versions ||= {}
version ? @@versions[version] : @@versions
end
def self.register_version( version, klass) versions[version] = klass end
# @param [Time,Integer,nil] timestamp Checked at this time
# @param [0..3] return_code `NSCA::ReturnCode`
# @param [String(length<64),nil] hostname If nil, local hostname will be used.
# Must be known by Nagios.
# @param [String(length<128)] service Name of Service. Must be known by Nagios.
# @param [String(length<512)] status Status-line inclusive optional Performance Data.
def initialize timestamp, return_code, hostname, service, status
@timestamp, @return_code, @hostname, @service, @status =
Time.at( timestamp.to_f), return_code, hostname, service, status
end
attr_accessor :timestamp, :return_code, :hostname, :service, :status
end
class PacketV3 < Packet
NAGIOS_VERSION = 2.7
PACKET_VERSION = 3
END_OF_TRANSMISSION = ?\x0a
HOSTNAME_LENGTH = 64
SERVICE_LENGTH = 128
PLUGIN_OUTPUT_LENGTH = 512
# these line describes the data package:
# typedef struct data_packet_struct{
# int16_t packet_version;
# /* two padding bytes (because aligning): xx */
# u_int32_t crc32_value;
# u_int32_t timestamp;
# int16_t return_code;
# char host_name[MAX_HOSTNAME_LENGTH];
# char svc_description[MAX_DESCRIPTION_LENGTH];
# char plugin_output[MAX_PLUGINOUTPUT_LENGTH];
# /* two extra padding-xx, too. */
# }data_packet;
PACK_STRING = "s> xx L> L> s> A#{HOSTNAME_LENGTH} A#{SERVICE_LENGTH} A#{PLUGIN_OUTPUT_LENGTH} xx"
PACK_LENGTH = 2+2+4+4+2+HOSTNAME_LENGTH+SERVICE_LENGTH+PLUGIN_OUTPUT_LENGTH+2
register_version PACKET_VERSION, self
# Builds a check-result-line for NSCA.
#
# Will be terminated by end-of-terminate.
def build slf = nil
cl = (slf || self).class
entry = [
cl::PACKET_VERSION,
0, # crc32 (unknown yet)
(timestamp || Time.now).to_i,
return_code.to_i,
NSCA::str2cstr_rand_padding( hostname || `hostname -f`, cl::HOSTNAME_LENGTH),
NSCA::str2cstr_rand_padding( service, cl::SERVICE_LENGTH),
NSCA::str2cstr_rand_padding( status, cl::PLUGIN_OUTPUT_LENGTH) # incl perfdata
]
# generate crc32 and put it at entry[2...6]
entry[1] = NSCA::crc32 entry.pack( cl::PACK_STRING)
entry = entry.pack cl::PACK_STRING
entry
end
def self.parse entry, no_verification_checks = nil
entry = entry.to_s.dup
ver, crc32sum, *x = entry.unpack( PACK_STRING)
x[2] = NSCA::cstr2str x[2]
x[3] = NSCA::cstr2str x[3]
x[4] = NSCA::cstr2str x[4]
raise VersionCheckFailed, "Packet version 3 expected. (recv: #{ver})" \
unless no_verification_checks or 3 == ver
entry[4..7] = ?\x00*4
crc32 = NSCA::crc32 entry
raise CSC32CheckFailed, "crc32-check failed. packet seems to be broken: #{crc32sum.inspect} != #{crc32.inspect}" \
unless no_verification_checks or crc32sum == crc32
new *x
end
end
class PacketV3__2_9 < PacketV3
NAGIOS_VERSION = 2.7
PACKET_VERSION = 3
END_OF_TRANSMISSION = ?\x0a
PLUGIN_OUTPUT_LENGTH = 4096
HOSTNAME_LENGTH = 64
SERVICE_LENGTH = 128
PACK_STRING = "s> xx L> L> s> A#{HOSTNAME_LENGTH} A#{SERVICE_LENGTH} A#{PLUGIN_OUTPUT_LENGTH} xx"
PACK_LENGTH = 2+2+4+4+2+HOSTNAME_LENGTH+SERVICE_LENGTH+PLUGIN_OUTPUT_LENGTH+2
end
end