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# -*- coding: utf-8 -*-
require 'stringio'
module CFPropertyList
# Binary PList parser class
class Binary
# Read a binary plist file
def load(opts)
@unique_table = {}
@count_objects = 0
@object_refs = 0
@written_object_count = 0
@object_table = []
@object_ref_size = 0
@offsets = []
fd = nil
if(opts.has_key?(:file))
fd = File.open(opts[:file],"rb")
file = opts[:file]
else
fd = StringIO.new(opts[:data],"rb")
file = "<string>"
end
# first, we read the trailer: 32 byte from the end
fd.seek(-32,IO::SEEK_END)
buff = fd.read(32)
offset_size, object_ref_size, number_of_objects, top_object, table_offset = buff.unpack "x6CCx4Nx4Nx4N"
# after that, get the offset table
fd.seek(table_offset, IO::SEEK_SET)
coded_offset_table = fd.read(number_of_objects * offset_size)
raise CFFormatError.new("#{file}: Format error!") unless coded_offset_table.bytesize == number_of_objects * offset_size
@count_objects = number_of_objects
# decode offset table
if(offset_size != 3)
formats = ["","C*","n*","","N*"]
@offsets = coded_offset_table.unpack(formats[offset_size])
else
@offsets = coded_offset_table.unpack("C*").each_slice(3).map {
|x,y,z| (x << 16) | (y << 8) | z
}
end
@object_ref_size = object_ref_size
val = read_binary_object_at(file,fd,top_object)
fd.close
val
end
# Convert CFPropertyList to binary format; since we have to count our objects we simply unique CFDictionary and CFArray
def to_str(opts={})
@unique_table = {}
@count_objects = 0
@object_refs = 0
@written_object_count = 0
@object_table = []
@offsets = []
binary_str = "bplist00"
@object_refs = count_object_refs(opts[:root])
opts[:root].to_binary(self)
next_offset = 8
offsets = @object_table.map do |object|
offset = next_offset
next_offset += object.bytesize
offset
end
binary_str << @object_table.join
table_offset = next_offset
offset_size = Binary.bytes_needed(table_offset)
if offset_size < 8
# Fast path: encode the entire offset array at once.
binary_str << offsets.pack((%w(C n N N)[offset_size - 1]) + '*')
else
# Slow path: host may be little or big endian, must pack each offset
# separately.
offsets.each do |offset|
binary_str << "#{Binary.pack_it_with_size(offset_size,offset)}"
end
end
binary_str << [offset_size, object_ref_size(@object_refs)].pack("x6CC")
binary_str << [@object_table.size].pack("x4N")
binary_str << [0].pack("x4N")
binary_str << [table_offset].pack("x4N")
binary_str
end
def object_ref_size object_refs
Binary.bytes_needed(object_refs)
end
# read a „null” type (i.e. null byte, marker byte, bool value)
def read_binary_null_type(length)
case length
when 0 then 0 # null byte
when 8 then CFBoolean.new(false)
when 9 then CFBoolean.new(true)
when 15 then 15 # fill type
else
raise CFFormatError.new("unknown null type: #{length}")
end
end
protected :read_binary_null_type
# read a binary int value
def read_binary_int(fname,fd,length)
if length > 4
raise CFFormatError.new("Integer greater than 16 bytes: #{length}")
end
nbytes = 1 << length
buff = fd.read(nbytes)
CFInteger.new(
case length
when 0 then buff.unpack("C")[0]
when 1 then buff.unpack("n")[0]
when 2 then buff.unpack("N")[0]
# 8 byte integers are always signed
when 3 then buff.unpack("q>")[0]
# 16 byte integers are used to represent unsigned 8 byte integers
# where the unsigned value is stored in the lower 8 bytes and the
# upper 8 bytes are unused.
when 4 then buff.unpack("Q>Q>")[1]
end
)
end
protected :read_binary_int
# read a binary real value
def read_binary_real(fname,fd,length)
raise CFFormatError.new("Real greater than 8 bytes: #{length}") if length > 3
nbytes = 1 << length
buff = fd.read(nbytes)
CFReal.new(
case length
when 0 # 1 byte float? must be an error
raise CFFormatError.new("got #{length+1} byte float, must be an error!")
when 1 # 2 byte float? must be an error
raise CFFormatError.new("got #{length+1} byte float, must be an error!")
when 2 then
buff.reverse.unpack("e")[0]
when 3 then
buff.reverse.unpack("E")[0]
else
fail "unexpected length: #{length}"
end
)
end
protected :read_binary_real
# read a binary date value
def read_binary_date(fname,fd,length)
raise CFFormatError.new("Date greater than 8 bytes: #{length}") if length > 3
nbytes = 1 << length
buff = fd.read(nbytes)
CFDate.new(
case length
when 0 then # 1 byte CFDate is an error
raise CFFormatError.new("#{length+1} byte CFDate, error")
when 1 then # 2 byte CFDate is an error
raise CFFormatError.new("#{length+1} byte CFDate, error")
when 2 then
buff.reverse.unpack("e")[0]
when 3 then
buff.reverse.unpack("E")[0]
end,
CFDate::TIMESTAMP_APPLE
)
end
protected :read_binary_date
# Read a binary data value
def read_binary_data(fname,fd,length)
CFData.new(read_fd(fd, length), CFData::DATA_RAW)
end
protected :read_binary_data
def read_fd fd, length
length > 0 ? fd.read(length) : ""
end
# Read a binary string value
def read_binary_string(fname,fd,length)
buff = read_fd fd, length
@unique_table[buff] = true unless @unique_table.has_key?(buff)
CFString.new(buff)
end
protected :read_binary_string
# Convert the given string from one charset to another
def Binary.charset_convert(str,from,to="UTF-8")
return str.dup.force_encoding(from).encode(to) if str.respond_to?("encode")
Iconv.conv(to,from,str)
end
# Count characters considering character set
def Binary.charset_strlen(str,charset="UTF-8")
if str.respond_to?(:encode)
size = str.length
else
utf8_str = Iconv.conv("UTF-8",charset,str)
size = utf8_str.scan(/./mu).size
end
# UTF-16 code units in the range D800-DBFF are the beginning of
# a surrogate pair, and count as one additional character for
# length calculation.
if charset =~ /^UTF-16/
if str.respond_to?(:encode)
str.bytes.to_a.each_slice(2) { |pair| size += 1 if (0xd8..0xdb).include?(pair[0]) }
else
str.split('').each_slice(2) { |pair| size += 1 if ("\xd8".."\xdb").include?(pair[0]) }
end
end
size
end
# Read a unicode string value, coded as UTF-16BE
def read_binary_unicode_string(fname,fd,length)
# The problem is: we get the length of the string IN CHARACTERS;
# since a char in UTF-16 can be 16 or 32 bit long, we don't really know
# how long the string is in bytes
buff = fd.read(2*length)
@unique_table[buff] = true unless @unique_table.has_key?(buff)
CFString.new(Binary.charset_convert(buff,"UTF-16BE","UTF-8"))
end
protected :read_binary_unicode_string
def unpack_with_size(nbytes, buff)
format = ["C*", "n*", "N*", "N*"][nbytes - 1];
if nbytes == 3
buff = "\0" + buff.scan(/.{1,3}/).join("\0")
end
return buff.unpack(format)
end
# Read an binary array value, including contained objects
def read_binary_array(fname,fd,length)
ary = []
# first: read object refs
if(length != 0)
buff = fd.read(length * @object_ref_size)
objects = unpack_with_size(@object_ref_size, buff) #buff.unpack(@object_ref_size == 1 ? "C*" : "n*")
# now: read objects
0.upto(length-1) do |i|
object = read_binary_object_at(fname,fd,objects[i])
ary.push object
end
end
CFArray.new(ary)
end
protected :read_binary_array
# Read a dictionary value, including contained objects
def read_binary_dict(fname,fd,length)
dict = {}
# first: read keys
if(length != 0) then
buff = fd.read(length * @object_ref_size)
keys = unpack_with_size(@object_ref_size, buff)
# second: read object refs
buff = fd.read(length * @object_ref_size)
objects = unpack_with_size(@object_ref_size, buff)
# read real keys and objects
0.upto(length-1) do |i|
key = read_binary_object_at(fname,fd,keys[i])
object = read_binary_object_at(fname,fd,objects[i])
dict[key.value] = object
end
end
CFDictionary.new(dict)
end
protected :read_binary_dict
# Read an object type byte, decode it and delegate to the correct
# reader function
def read_binary_object(fname,fd)
# first: read the marker byte
buff = fd.read(1)
object_length = buff.unpack("C*")
object_length = object_length[0] & 0xF
buff = buff.unpack("H*")
object_type = buff[0][0].chr
if(object_type != "0" && object_length == 15) then
object_length = read_binary_object(fname,fd)
object_length = object_length.value
end
case object_type
when '0' # null, false, true, fillbyte
read_binary_null_type(object_length)
when '1' # integer
read_binary_int(fname,fd,object_length)
when '2' # real
read_binary_real(fname,fd,object_length)
when '3' # date
read_binary_date(fname,fd,object_length)
when '4' # data
read_binary_data(fname,fd,object_length)
when '5' # byte string, usually utf8 encoded
read_binary_string(fname,fd,object_length)
when '6' # unicode string (utf16be)
read_binary_unicode_string(fname,fd,object_length)
when '8'
CFUid.new(read_binary_int(fname, fd, object_length).value)
when 'a' # array
read_binary_array(fname,fd,object_length)
when 'd' # dictionary
read_binary_dict(fname,fd,object_length)
end
end
protected :read_binary_object
# Read an object type byte at position $pos, decode it and delegate to the correct reader function
def read_binary_object_at(fname,fd,pos)
position = @offsets[pos]
fd.seek(position,IO::SEEK_SET)
read_binary_object(fname,fd)
end
protected :read_binary_object_at
# pack an +int+ of +nbytes+ with size
def Binary.pack_it_with_size(nbytes,int)
case nbytes
when 1 then [int].pack('c')
when 2 then [int].pack('n')
when 4 then [int].pack('N')
when 8
[int >> 32, int & 0xFFFFFFFF].pack('NN')
else
raise CFFormatError.new("Don't know how to pack #{nbytes} byte integer")
end
end
def Binary.pack_int_array_with_size(nbytes, array)
case nbytes
when 1 then array.pack('C*')
when 2 then array.pack('n*')
when 4 then array.pack('N*')
when 8
array.map { |int| [int >> 32, int & 0xFFFFFFFF].pack('NN') }.join
else
raise CFFormatError.new("Don't know how to pack #{nbytes} byte integer")
end
end
# calculate how many bytes are needed to save +count+
def Binary.bytes_needed(count)
case
when count < 2**8 then 1
when count < 2**16 then 2
when count < 2**32 then 4
when count < 2**64 then 8
else
raise CFFormatError.new("Data size too large: #{count}")
end
end
# Create a type byte for binary format as defined by apple
def Binary.type_bytes(type, length)
if length < 15
[(type << 4) | length].pack('C')
else
bytes = [(type << 4) | 0xF]
if length <= 0xFF
bytes.push(0x10, length).pack('CCC') # 1 byte length
elsif length <= 0xFFFF
bytes.push(0x11, length).pack('CCn') # 2 byte length
elsif length <= 0xFFFFFFFF
bytes.push(0x12, length).pack('CCN') # 4 byte length
elsif length <= 0x7FFFFFFFFFFFFFFF
bytes.push(0x13, length >> 32, length & 0xFFFFFFFF).pack('CCNN') # 8 byte length
else
raise CFFormatError.new("Integer too large: #{int}")
end
end
end
def count_object_refs(object)
case object
when CFArray
contained_refs = 0
object.value.each do |element|
if CFArray === element || CFDictionary === element
contained_refs += count_object_refs(element)
end
end
return object.value.size + contained_refs
when CFDictionary
contained_refs = 0
object.value.each_value do |value|
if CFArray === value || CFDictionary === value
contained_refs += count_object_refs(value)
end
end
return object.value.keys.size * 2 + contained_refs
else
return 0
end
end
def Binary.ascii_string?(str)
if str.respond_to?(:ascii_only?)
str.ascii_only?
else
str !~ /[\x80-\xFF]/mn
end
end
# Uniques and transforms a string value to binary format and adds it to the object table
def string_to_binary(val)
val = val.to_s
@unique_table[val] ||= begin
if !Binary.ascii_string?(val)
val = Binary.charset_convert(val,"UTF-8","UTF-16BE")
bdata = Binary.type_bytes(0b0110, Binary.charset_strlen(val,"UTF-16BE"))
val.force_encoding("ASCII-8BIT") if val.respond_to?("encode")
@object_table[@written_object_count] = bdata << val
else
bdata = Binary.type_bytes(0b0101,val.bytesize)
@object_table[@written_object_count] = bdata << val
end
@written_object_count += 1
@written_object_count - 1
end
end
# Codes an integer to binary format
def int_to_binary(value)
# Note: nbytes is actually an exponent. number of bytes = 2**nbytes.
nbytes = 0
nbytes = 1 if value > 0xFF # 1 byte unsigned integer
nbytes += 1 if value > 0xFFFF # 4 byte unsigned integer
nbytes += 1 if value > 0xFFFFFFFF # 8 byte unsigned integer
nbytes += 1 if value > 0x7FFFFFFFFFFFFFFF # 8 byte unsigned integer, stored in lower half of 16 bytes
nbytes = 3 if value < 0 # signed integers always stored in 8 bytes
Binary.type_bytes(0b0001, nbytes) <<
if nbytes < 4
[value].pack(["C", "n", "N", "q>"][nbytes])
else # nbytes == 4
[0,value].pack("Q>Q>")
end
end
# Codes a real value to binary format
def real_to_binary(val)
Binary.type_bytes(0b0010,3) << [val].pack("E").reverse
end
# Converts a numeric value to binary and adds it to the object table
def num_to_binary(value)
@object_table[@written_object_count] =
if value.is_a?(CFInteger)
int_to_binary(value.value)
else
real_to_binary(value.value)
end
@written_object_count += 1
@written_object_count - 1
end
def uid_to_binary(value)
nbytes = 0
nbytes = 1 if value > 0xFF # 1 byte integer
nbytes += 1 if value > 0xFFFF # 4 byte integer
nbytes += 1 if value > 0xFFFFFFFF # 8 byte integer
nbytes = 3 if value < 0 # 8 byte integer, since signed
@object_table[@written_object_count] = Binary.type_bytes(0b1000, nbytes) <<
if nbytes < 3
[value].pack(
if nbytes == 0 then "C"
elsif nbytes == 1 then "n"
else "N"
end
)
else
# 64 bit signed integer; we need the higher and the lower 32 bit of the value
high_word = value >> 32
low_word = value & 0xFFFFFFFF
[high_word,low_word].pack("NN")
end
@written_object_count += 1
@written_object_count - 1
end
# Convert date value (apple format) to binary and adds it to the object table
def date_to_binary(val)
val = val.getutc.to_f - CFDate::DATE_DIFF_APPLE_UNIX # CFDate is a real, number of seconds since 01/01/2001 00:00:00 GMT
@object_table[@written_object_count] =
(Binary.type_bytes(0b0011, 3) << [val].pack("E").reverse)
@written_object_count += 1
@written_object_count - 1
end
# Convert a bool value to binary and add it to the object table
def bool_to_binary(val)
@object_table[@written_object_count] = val ? "\x9" : "\x8" # 0x9 is 1001, type indicator for true; 0x8 is 1000, type indicator for false
@written_object_count += 1
@written_object_count - 1
end
# Convert data value to binary format and add it to the object table
def data_to_binary(val)
@object_table[@written_object_count] =
(Binary.type_bytes(0b0100, val.bytesize) << val)
@written_object_count += 1
@written_object_count - 1
end
# Convert array to binary format and add it to the object table
def array_to_binary(val)
saved_object_count = @written_object_count
@written_object_count += 1
#@object_refs += val.value.size
values = val.value.map { |v| v.to_binary(self) }
bdata = Binary.type_bytes(0b1010, val.value.size) <<
Binary.pack_int_array_with_size(object_ref_size(@object_refs),
values)
@object_table[saved_object_count] = bdata
saved_object_count
end
# Convert dictionary to binary format and add it to the object table
def dict_to_binary(val)
saved_object_count = @written_object_count
@written_object_count += 1
#@object_refs += val.value.keys.size * 2
keys_and_values = val.value.keys.map { |k| CFString.new(k).to_binary(self) }
keys_and_values.concat(val.value.values.map { |v| v.to_binary(self) })
bdata = Binary.type_bytes(0b1101,val.value.size) <<
Binary.pack_int_array_with_size(object_ref_size(@object_refs), keys_and_values)
@object_table[saved_object_count] = bdata
return saved_object_count
end
end
end
# eof