lib/metasploit/framework/afp/client.rb
# -*- coding: binary -*-
module Metasploit
module Framework
module AFP
module Client
def next_id
@request_id ||= -1
@request_id += 1
@request_id
end
def get_info
packet = "\00" # Flag: Request
packet << "\x03" # Command: FPGetSrvrInfo
packet << [next_id].pack('n') # requestID
packet << "\x00\x00\x00\x00" # Data offset
packet << "\x00\x00\x00\x00" # Length
packet << "\x00\x00\x00\x00" # Reserved
sock.put(packet)
response = sock.timed_read(1024)
return parse_info_response(response)
end
def open_session
packet = "\00" # Flag: Request
packet << "\x04" # Command: DSIOpenSession
packet << [next_id].pack('n') # requestID
packet << "\x00\x00\x00\x00" # Data offset
packet << "\x00\x00\x00\x06" # Length
packet << "\x00\x00\x00\x00" # Reserved
packet << "\x01" # Attention Quantum
packet << "\x04" # Length
packet << "\x00\x00\x04\x00" # 1024
sock.put(packet)
response = sock.timed_read(1024)
return parse_open_session_response(response)
end
def login(user, pass)
if user == ''
return no_user_authent_login
end
p = OpenSSL::BN.new("BA2873DFB06057D43F2024744CEEE75B", 16)
g = OpenSSL::BN.new("7", 10)
ra = OpenSSL::BN.new('86F6D3C0B0D63E4B11F113A2F9F19E3BBBF803F28D30087A1450536BE979FD42', 16)
ma = g.mod_exp(ra, p)
padded_user = (user.length + 1) % 2 != 0 ? user + "\x00" : user
bin_user = [padded_user.length, padded_user].pack("Ca*")
length = 18 + bin_user.length + ma.to_s(2).length
packet = "\00" # Flag: Request
packet << "\x02" # Command: DSICommand
packet << [next_id].pack('n') # requestID
packet << "\x00\x00\x00\x00" # Data offset
packet << [length].pack('N') # Length (42)
packet << "\x00\x00\x00\x00" # Reserved
packet << "\x12" # AFPCommand: FPLogin (18)
packet << "\x06\x41\x46\x50\x33\x2e\x31" # AFPVersion: AFP3.1
packet << "\x09\x44\x48\x43\x41\x53\x54\x31\x32\x38" #UAM: DHCAST128
packet << bin_user # username
packet << ma.to_s(2) # random number
sock.put(packet)
begin
response = sock.timed_read(1024, self.login_timeout)
rescue Timeout::Error
raise RuntimeError, "AFP Login timeout (AFP server delay response for 20 - 22 seconds after 7 incorrect logins)"
end
flags, command, request_id, error_code, length, reserved = parse_header(response)
case error_code
when -5001 #kFPAuthContinue
return parse_login_response_add_send_login_count(response, {:p => p, :g => g, :ra => ra, :ma => ma,
:password => pass, :user => user})
when -5023 #kFPUserNotAuth (User doesn't exists)
return :skip_user
else
return :connection_error
end
end
def close_session
packet = "\00" # Flag: Request
packet << "\x01" # Command: DSICloseSession
packet << [next_id].pack('n') # requestID
packet << "\x00\x00\x00\x00" #Data offset
packet << "\x00\x00\x00\x00" #Length
packet << "\x00\x00\x00\x00" #Reserved
sock.put(packet)
end
def no_user_authent_login
packet = "\00" # Flag: Request
packet << "\x02" # Command: DSICommand
packet << [next_id].pack('n') # requestID
packet << "\x00\x00\x00\x00" # Data offset
packet << "\x00\x00\x00\x18" # Length (24)
packet << "\x00\x00\x00\x00" # Reserved
packet << "\x12" # AFPCommand: FPLogin (18)
packet << "\x06\x41\x46\x50\x33\x2e\x31" #AFP3.1
packet << "\x0f\x4e\x6f\x20\x55\x73\x65\x72\x20\x41\x75\x74\x68\x65\x6e\x74" #UAM: No User Authent
sock.put(packet)
begin
response = sock.timed_read(1024, self.login_timeout)
rescue Timeout::Error
raise RuntimeError, "AFP Login timeout (AFP server delay response for 20 - 22 seconds after 7 incorrect logins)"
end
flags, command, request_id, error_code, length, reserved = parse_header(response)
if error_code == 0
return :true
else
return false
end
end
def parse_login_response_add_send_login_count(response, data)
dhx_s2civ = 'CJalbert'
dhx_c2civ = 'LWallace'
flags, command, request_id, error_code, length, reserved = parse_header(response)
body = get_body(response, length)
id, mb, enc_data = body.unpack("nH32a*")
mb = OpenSSL::BN.new(mb, 16)
k = mb.mod_exp(data[:ra], data[:p] )
cipher = OpenSSL::Cipher.new('cast5-cbc').decrypt
cipher.key = k.to_s(2)
cipher.iv = dhx_s2civ
cipher.padding = 0
nonce = cipher.update(enc_data)
nonce << cipher.final
nonce = nonce[0..15]
nonce = OpenSSL::BN.new(nonce, 2) + 1
plain_text = nonce.to_s(2) + data[:password].ljust(64, "\x00")
cipher = OpenSSL::Cipher.new('cast5-cbc').encrypt
cipher.key = k.to_s(2)
cipher.iv = dhx_c2civ
auth_response = cipher.update(plain_text)
auth_response << cipher.final
packet = "\00" # Flag: Request
packet << "\x02" # Command: DSICommand
packet << [next_id].pack('n') # requestID
packet << "\x00\x00\x00\x00" # Data offset
packet << [auth_response.length + 2].pack("N") # Length
packet << "\x00\x00\x00\x00" # Reserved
packet << "\x13" # AFPCommand: FPLoginCont (19)
packet << "\x00"
packet << [id].pack('n')
packet << auth_response
sock.put(packet)
begin
response = sock.timed_read(1024, self.login_timeout)
rescue Timeout::Error
raise RuntimeError, "AFP Login timeout (AFP server delay response for 20 - 22 seconds after 7 incorrect logins)"
end
flags, command, request_id, error_code, length, reserved = parse_header(response)
if error_code == 0
return true
else
return false
end
end
def parse_open_session_response(response)
_, _, _, error_code, _, _ = parse_header(response)
return error_code == 0 ? true : false
end
def parse_info_response(response)
parsed_data = {}
flags, command, request_id, error_code, length, reserved = parse_header(response)
raise RuntimeError, "AFP Server response with error" if error_code != 0
body = get_body(response, length)
machine_type_offset, afp_versions_offset, uam_count_offset, icon_offset, server_flags =
body.unpack('nnnnn')
server_name_length = body.unpack('@10C').first
parsed_data[:server_name] = body.unpack("@11A#{server_name_length}").first
pos = 11 + server_name_length
pos += 1 if pos % 2 != 0 #padding
server_signature_offset, network_addresses_offset, directory_names_offset,
utf8_servername_offset = body.unpack("@#{pos}nnnn")
parsed_data[:machine_type] = read_pascal_string(body, machine_type_offset)
parsed_data[:versions] = read_array(body, afp_versions_offset)
parsed_data[:uams] = read_array(body, uam_count_offset)
# skipped icon
parsed_data[:server_flags] = parse_flags(server_flags)
parsed_data[:signature] = body.unpack("@#{server_signature_offset}H32").first
network_addresses = read_array(body, network_addresses_offset, true)
parsed_data[:network_addresses] = parse_network_addresses(network_addresses)
# skipped directory names
#Error catching for offset issues on this field. Need better error handling all through here
begin
parsed_data[:utf8_server_name] = read_utf8_pascal_string(body, utf8_servername_offset)
rescue
parsed_data[:utf8_server_name] = "N/A"
end
return parsed_data
end
def parse_header(packet)
header = packet.unpack('CCnNNN') #ruby 1.8.7 don't support unpacking signed integers in big-endian order
header[3] = packet[4..7].reverse.unpack("l").first
return header
end
def get_body(packet, body_length)
body = packet[16..body_length + 15]
raise RuntimeError, "AFP Invalid body length" if body.length != body_length
return body
end
def read_pascal_string(str, offset)
length = str.unpack("@#{offset}C").first
return str.unpack("@#{offset + 1}A#{length}").first
end
def read_utf8_pascal_string(str, offset)
length = str.unpack("@#{offset}n").first
return str[offset + 2..offset + length + 1]
end
def read_array(str, offset, afp_network_address=false)
size = str.unpack("@#{offset}C").first
pos = offset + 1
result = []
size.times do
result << read_pascal_string(str, pos)
pos += str.unpack("@#{pos}C").first
pos += 1 unless afp_network_address
end
return result
end
def parse_network_addresses(network_addresses)
parsed_addreses = []
network_addresses.each do |address|
case address.unpack('C').first
when 0 #Reserved
next
when 1 # Four-byte IP address
parsed_addreses << IPAddr.ntop(address[1..4]).to_s
when 2 # Four-byte IP address followed by a two-byte port number
parsed_addreses << "#{IPAddr.ntop(address[1..4])}:#{address[5..6].unpack("n").first}"
when 3 # DDP address (deprecated)
next
when 4 # DNS name (maximum of 254 bytes)
parsed_addreses << address[1..address.length - 1]
when 5 # This functionality is deprecated.
next
when 6 # IPv6 address (16 bytes)
parsed_addreses << "[#{IPAddr.ntop(address[1..16])}]"
when 7 # IPv6 address (16 bytes) followed by a two-byte port number
parsed_addreses << "[#{IPAddr.ntop(address[1..16])}]:#{address[17..18].unpack("n").first}"
else # Something wrong?
raise RuntimeError, "Error parsing network addresses"
end
end
return parsed_addreses
end
def parse_flags(flags)
flags = flags.to_s(2)
result = {}
result['Super Client'] = flags[0,1] == '1' ? true : false
result['UUIDs'] = flags[5,1] == '1' ? true : false
result['UTF8 Server Name'] = flags[6,1] == '1' ? true : false
result['Open Directory'] = flags[7,1] == '1' ? true : false
result['Reconnect'] = flags[8,1] == '1' ? true : false
result['Server Notifications'] = flags[9,1] == '1' ? true : false
result['TCP/IP'] = flags[10,1] == '1' ? true : false
result['Server Signature'] = flags[11,1] == '1' ? true : false
result['Server Messages'] = flags[12,1] == '1' ? true : false
result['Password Saving Prohibited'] = flags[13,1] == '1' ? true : false
result['Password Changing'] = flags[14,1] == '1' ? true : false
result['Copy File'] = flags[5,1] == '1' ? true : false
return result
end
end
end
end
end