emailler/server/lib/tndp.rb

394 lines
14 KiB
Ruby

#
# message formats for Trivial Network Disk Protocol
#
$:.unshift(File.dirname(__FILE__)) unless
$:.include?(File.dirname(__FILE__)) || $:.include?(File.expand_path(File.dirname(__FILE__)))
require 'SubclassTracking'
#useful extension to Hash class
class Hash
def key_by_value(value)
self.keys.each do |key|
return key if self[key]==value
end
nil
end
end
module TNDP
OPCODES={
0x00 =>"CAPABILITIES REQUEST",
0x01 =>"VOLUME CATALOG REQUEST",
0x02 =>"READ SECTOR REQUEST",
0x03 =>"WRITE SECTOR REQUEST",
0x80 =>"CAPABILITIES RESPONSE",
0x81 =>"VOLUME CATALOG RESPONSE",
0x82 =>"READ SECTOR RESPONSE",
0x83 =>"WRITE SECTOR RESPONSE",
0xFF =>"ERROR RESPONSE",
}
MAX_CATALOG_ENTRIES_PER_MESSAGE=8
MAX_VOLUME_NAME_LENGTH=127
SYSTEM_ARCHITECTURES={
:any=>0x00,
:c64=>0x64,
:apple2=>0xA2,
:unknown=>0xFF,
}
FILESYSTEMS={
:any=>0x00,
:raw=>0x01,
:apple_dos_33=>0x02,
:prodos=>0x03,
:cpm=>0x04,
:cbm_dos=>0x05,
:unknown=>0xFF,
}
class ErrorCodes
OK=0x00
UNKNOWN_OPCODE=0x02
VERSION_NOT_SUPPORTED=0x03
ARCHITECTURE_NOT_SUPPORTED=0x04
FILESYSTEM_NOT_SUPPORTED=0x05
INVALID_VOLUME_NAME=0x06
INVALID_TRACK_NUMBER=0x07
INVALID_SECTOR_NUMBER=0x08
INVALID_SECTOR_LENGTH=0x09
INTERNAL_SERVER_ERROR=0xFF
end
class FormatError <RuntimeError
end
class BufferTooShort < FormatError
end
class InvalidSignature < FormatError
end
class InvalidVersion < FormatError
end
class InvalidOpcode < FormatError
end
def TNDP.hex_dump(buffer)
s=""
(0..(buffer.length/16)).each {|line_number|
lhs=""
rhs=""
start_byte=line_number*16
line=buffer[start_byte,16]
if line.length>0 then
line.each_byte {|byte|
lhs+= sprintf("%02X ", byte)
rhs+=byte.chr.sub(/[\x00-\x1f]/,'.')
}
lhs+=" "*(16-line.length)*3
s+=sprintf("%02X\t%s %s\n",start_byte,lhs,rhs)
end
}
s
end
def TNDP.coalesce(a,b)
if a.nil? then
b
else
a
end
end
@@next_transaction_id=0
def TNDP.next_transaction_id
@@next_transaction_id+=1
@@next_transaction_id
end
MESSAGE_SIGNATURE='TNDP'
VERSION_ID=1
def TNDP.message_from_buffer(buffer)
raise BufferTooShort unless buffer.length>=0x07
signature,version_id,transaction_id,opcode=buffer.unpack("Z4CnC")
raise InvalidSignature unless signature==MESSAGE_SIGNATURE
raise InvalidVersion unless version_id==1
BaseMessage.subclasses.each do |msg_type|
next unless defined?(msg_type::OPCODE)
return msg_type.from_buffer(buffer) if opcode==msg_type::OPCODE
end
raise InvalidOpcode
end
class BaseMessage
attr_accessor :signature,:version_id,:transaction_id,:opcode,:raw_bytes
def raw_bytes
@raw_bytes=to_buffer if @raw_bytes.nil?
@raw_bytes
end
def to_buffer
packed_buffer=[signature,version_id,transaction_id,opcode].pack("Z4cnC")
packed_buffer
end
def to_s
hex_dump+
"
TNDP MESSAGE
SIGNATURE: #{signature}
VERSION: #{version_id}
TRANSACTION ID: $#{"%04x"%transaction_id}
OPCODE: $#{"%02X"%opcode} [#{OPCODES[opcode].nil? ? "UNKNOWN" : OPCODES[opcode]}]"
end
def hex_dump
TNDP.hex_dump(raw_bytes)
end
def initialize(args={})
@signature=TNDP.coalesce(args[:signature],MESSAGE_SIGNATURE)
@version_id=TNDP.coalesce(args[:version_id],0x01)
@transaction_id=TNDP.coalesce(args[:transaction_id],TNDP.next_transaction_id)
@opcode=TNDP.coalesce(args[:opcode],0xFF)
end
private
def self.from_buffer(buffer)
signature,version_id,transaction_id,opcode=buffer.unpack("Z4CnC")
self.new({:signature=>signature,:version=>version_id,:transaction_id=>transaction_id,:opcode=>opcode})
end
self.extend SubclassTracking
end
class CapabilitiesRequestMessage < BaseMessage
OPCODE=0x00
def initialize(args={})
args[:opcode]=OPCODE
super(args)
end
end
class CapabilitiesResponseMessage < BaseMessage
OPCODE=0x80
attr_reader :application_name,:highest_supported_version_id,:supported_architectures
def initialize(args={})
args[:opcode]=OPCODE
@application_name=TNDP.coalesce(args[:application_name],"netboot 65")
@highest_supported_version_id=TNDP.coalesce(args[:highest_supported_version_id],VERSION_ID)
@supported_architectures=TNDP.coalesce(args[:supported_architectures],[[:any,0]])
super(args)
end
def to_s
s=""
supported_architectures.each do |entry|
system_architecture_id=TNDP::SYSTEM_ARCHITECTURES[entry[0]]
count=entry[1]
s<<"\n%s [0x%02X] - 0x%04X" % [entry[0],system_architecture_id,count]
end
super+s
end
def to_buffer
supported_architectures_buffer=[supported_architectures.length].pack("C")
supported_architectures.each{|a| supported_architectures_buffer+=[TNDP::SYSTEM_ARCHITECTURES[a[0]],a[1]].pack("CC")}
super+[highest_supported_version_id,application_name].pack("CZ20")+supported_architectures_buffer
end
def self.from_buffer(buffer)
signature,version_id,transaction_id,opcode,highest_supported_version_id,application_name,supported_architectures_length=buffer.unpack("Z4CnCCZ20C")
supported_architectures={}
supported_architectures_length.times do |i|
system_architecture_id=buffer[(i*2)+0x1E]
system_architecture=TNDP.coalesce(TNDP::SYSTEM_ARCHITECTURES.key_by_value(system_architecture_id),:unknown)
count=buffer[(i*2)+0x1F]
supported_architectures[system_architecture]=count
end
self.new({:signature=>signature,:version=>version_id,:transaction_id=>transaction_id,
:opcode=>opcode,:application_name=>application_name,:highest_supported_version_id=>highest_supported_version_id,:supported_architectures=>supported_architectures})
end
end
class VolumeCatalogRequestMessage < BaseMessage
attr_reader :system_architecture, :file_system, :catalog_offset
OPCODE=0x01
def initialize(args={})
args[:opcode]=OPCODE
@system_architecture=TNDP.coalesce(TNDP::SYSTEM_ARCHITECTURES.key_by_value(TNDP::SYSTEM_ARCHITECTURES[args[:system_architecture]]),:any)
@file_system=TNDP.coalesce(TNDP::FILESYSTEMS.key_by_value(TNDP::FILESYSTEMS[args[:file_system]]),:any)
@catalog_offset=TNDP.coalesce(args[:catalog_offset],0)
super(args)
end
def to_s
system_architecture_id=TNDP::SYSTEM_ARCHITECTURES[system_architecture]
file_system_id=TNDP::FILESYSTEMS[file_system]
super+"
ARCHITECTURE: #{system_architecture} [$#{"%02X"%system_architecture_id}]
FILE SYSTEM: #{file_system} [$#{"%02X"%file_system_id}]
CATALOG OFFSET: $#{"%04x" % catalog_offset}"
end
def to_buffer
super+[TNDP::SYSTEM_ARCHITECTURES[system_architecture],TNDP::FILESYSTEMS[file_system],catalog_offset].pack("CCn")
end
def self.from_buffer(buffer)
signature,version_id,transaction_id,opcode,system_architecture_id,file_system_id,catalog_offset=buffer.unpack("Z4CnCCCn")
self.new({:signature=>signature,:version=>version_id,:transaction_id=>transaction_id,
:opcode=>opcode,:system_architecture=>TNDP::SYSTEM_ARCHITECTURES.key_by_value(system_architecture_id),:file_system=>TNDP::FILESYSTEMS.key_by_value(file_system_id),:catalog_offset=>catalog_offset})
end
end
class VolumeCatalogResponseMessage < BaseMessage
attr_reader :catalog_offset,:total_catalog_size,:catalog_entries
OPCODE=0x81
def initialize(args={})
args[:opcode]=OPCODE
@catalog_entries=TNDP.coalesce(args[:catalog_entries],[])
@catalog_offset=TNDP.coalesce(args[:catalog_offset],0)
@total_catalog_size=TNDP.coalesce(args[:total_catalog_size],0)
super(args)
end
def to_s
s="\nCATALOG ENTRIES:\n___________________"
catalog_entries.each do |entry|
s<<"\nVOLUME NAME: %s\n\tSYSTEM ARCHITECTURE: %s\n\tFILE SYSTEM: %s\n\tTRACKS : 0x%04X\n\tSECTOR SIZE: 0x%04X" % entry
end
super+"
CATALOG SIZE: $#{"%04x" % total_catalog_size}
CATALOG OFFSET: $#{"%04x" % catalog_offset}"+s
end
def to_buffer
catalog_buffer=[total_catalog_size,catalog_offset,catalog_entries.length].pack("nnC")
catalog_entries.each do |entry|
catalog_buffer+=[entry[0][0,TNDP::MAX_VOLUME_NAME_LENGTH],TNDP::SYSTEM_ARCHITECTURES[entry[1]],TNDP::FILESYSTEMS[entry[2]],entry[3],entry[4]].pack("Z#{TNDP::MAX_VOLUME_NAME_LENGTH+1}CCnn")
end
super+catalog_buffer
end
def self.from_buffer(buffer)
signature,version_id,transaction_id,opcode,total_catalog_size,catalog_offset,catalog_entries_length=buffer.unpack("Z4CnCnnC")
catalog_entries=[]
catalog_entries_length.times do |i|
entry_buffer=buffer[0x0D+(i*(TNDP::MAX_VOLUME_NAME_LENGTH+7)),TNDP::MAX_VOLUME_NAME_LENGTH+7]
volume_name,system_architecture_id,file_system_id,track_count,sector_size=entry_buffer.unpack("Z#{TNDP::MAX_VOLUME_NAME_LENGTH+1}CCnn")
system_architecture=TNDP.coalesce(TNDP::SYSTEM_ARCHITECTURES.key_by_value(system_architecture_id),:unknown)
file_system=TNDP.coalesce(TNDP::FILESYSTEMS.key_by_value(file_system_id),:unknown)
catalog_entries<<[volume_name,system_architecture,file_system,track_count,sector_size]
end
self.new({:signature=>signature,:version=>version_id,:transaction_id=>transaction_id,
:opcode=>opcode,:total_catalog_size=>total_catalog_size,:catalog_offset=>catalog_offset,:catalog_entries=>catalog_entries})
end
end
class SectorReadRequestMessage < BaseMessage
attr_reader :track_no,:sector_no,:sector_length,:volume_name
OPCODE=0x02
def initialize(args={})
args[:opcode]=OPCODE
[:track_no,:sector_no,:sector_length,:volume_name].each do |arg|
raise "#{arg} must be specified in a #{self.class}" if args[arg].nil?
end
@track_no=args[:track_no]
@sector_no=args[:sector_no]
@sector_length=args[:sector_length]
@volume_name=args[:volume_name]
super(args)
end
def to_s
super+"
VOLUME NAME: #{volume_name}
TRACK NO: $#{"%04X"%track_no}
SECTOR NO: $#{"%04X"%sector_no}
SECTOR LENGTH: $#{"%04x" % sector_length}"
end
def to_buffer
super+[track_no,sector_no,sector_length,volume_name[0,MAX_VOLUME_NAME_LENGTH]].pack("nnnZ#{TNDP::MAX_VOLUME_NAME_LENGTH+1}")
end
def self.from_buffer(buffer)
signature,version_id,transaction_id,opcode,track_no,sector_no,sector_length,volume_name=buffer.unpack("Z4CnCnnnZ#{TNDP::MAX_VOLUME_NAME_LENGTH+1}")
self.new({:signature=>signature,:version=>version_id,:transaction_id=>transaction_id,
:opcode=>opcode,:track_no=>track_no,:sector_no=>sector_no,:sector_length=>sector_length,:volume_name=>volume_name})
end
end
class SectorReadResponseMessage < SectorReadRequestMessage
OPCODE=0x82
attr_reader :sector_data
def initialize(args={})
raise "sector_data must be specified in a #{self.class}" if args[:sector_data].nil?
@sector_data=args[:sector_data]
super(args)
@opcode=OPCODE
raise "length of sector_data #{@sector_data.length} must match specified sector_length #{@sector_length}" unless @sector_data.length==@sector_length
end
def to_s
super+"\nSECTOR DATA:\n"+TNDP.hex_dump(sector_data)
end
def to_buffer
super+[sector_data].pack("A#{sector_length}")
end
def self.from_buffer(buffer)
signature,version_id,transaction_id,opcode,track_no,sector_no,sector_length,volume_name,sector_data=buffer.unpack("Z4CnCnnnZ#{TNDP::MAX_VOLUME_NAME_LENGTH+1}a*")
self.new({:signature=>signature,:version=>version_id,:transaction_id=>transaction_id,
:opcode=>opcode,:track_no=>track_no,:sector_no=>sector_no,:sector_length=>sector_length,:volume_name=>volume_name,:sector_data=>sector_data})
end
end
class ErrorResponseMessage < BaseMessage
OPCODE=0xFF
attr_reader :errorcode,:error_description,:original_data_elements
def initialize(args={})
args[:opcode]=OPCODE
@errorcode=TNDP.coalesce(args[:errorcode],0xFF)
@error_description=TNDP.coalesce(args[:error_description],"an error occured")
@original_data_elements=TNDP.coalesce(args[:original_data_elements],"")
super(args)
end
def self.from_buffer(buffer)
signature,version_id,transaction_id,opcode,errorcode,error_description,original_data_elements=buffer.unpack("Z4CnCnZ128Z16")
self.new({:signature=>signature,:version=>version_id,:transaction_id=>transaction_id,
:opcode=>opcode,:errorcode=>errorcode,:error_description=>error_description,:original_data_elements=>original_data_elements})
end
def to_s
super+"
ERROR CODE: $#{"%02X"%errorcode}
DESCRIPTION: #{error_description}
ORIGINAL DATA: #{original_data_elements}
"
end
def to_buffer
super+[errorcode,error_description,0,original_data_elements].pack("nZ127CZ16")
end
def self.create_error_response(original_request_buffer,errorcode,error_description)
transaction_id=original_request_buffer[5,2].unpack("n")[0] #pull direct from data in case "message_from_buffer" was what raised the error
self.new({:signature=>MESSAGE_SIGNATURE,:version=>VERSION_ID,:transaction_id=>transaction_id,
:opcode=>OPCODE,:errorcode=>errorcode,:error_description=>error_description,:original_data_elements=>original_request_buffer[0,16]})
end
end
end