diff options
| -rw-r--r-- | src/zip.cr | 239 |
1 files changed, 181 insertions, 58 deletions
@@ -18,8 +18,9 @@ require "zlib" # [x] add zip64 extras when writing header and central # [x] add zip64 archive footer # [x] update sizes to be u64 -# [ ] reader support +# [x] reader support # [ ] choose zip64 default for arbitrary IOs (right now it is false) +# [ ] testing # [ ] legacy unicode (e.g., non-bit 11) path/comment support # [ ] unix uids # [ ] encryption @@ -76,6 +77,12 @@ module Zip # :nodoc: LE = IO::ByteFormat::LittleEndian + # :nodoc: + # Static, zero-length `Bytes` used when empty buffer reference is + # needed. + # :nodoc: + EMPTY_SLICE = Bytes.new(0) + # # Size of internal buffers, in bytes. # @@ -360,9 +367,9 @@ module Zip # by internal classes. # def initialize(v : UInt16) - @compat = v >> 8 - @major = (v & 0xff) / 10 - @minor = (v & 0xff) % 10 + @compat = v.to_i >> 8 + @major = (v.to_i & 0xff) / 10 + @minor = (v.to_i & 0xff) % 10 end # @@ -769,7 +776,7 @@ module Zip # add zip64 to list of extras es << Extra::Zip64.new( - file_size: 0_u64, + size: 0_u64, compressed_size: 0_u64, pos: (@pos >= UInt32::MAX) ? @pos : nil, ) @@ -1629,17 +1636,17 @@ module Zip # # Return number of bytes needed for this Extra. # - def size : UInt16 + def bytes_needed : UInt16 4.to_u16 + @data.size.to_u16 end def to_s(io) : UInt16 - @code.to_io(io, LE) + @code.to_u64.to_io(io, LE) @data.size.to_u16.to_io(io, LE) @data.to_s(io) # return number of bytes written - size + bytes_needed end end @@ -1653,7 +1660,7 @@ module Zip # # File size (64-bit unsigned integer). # - getter :file_size + getter :size # # Compressed file size (64-bit unsigned integer). @@ -1683,20 +1690,20 @@ module Zip # created as-needed by `Writer#add()`. # def initialize( - @file_size : UInt64 = 0_u64, + @size : UInt64 = 0_u64, @compressed_size : UInt64 = 0_u64, @pos : UInt64? = nil, @disk_start : UInt32? = nil, ) len = 16_u32 - len += 8 if @pos && @disk_start + len += 8 if @pos len += 4 if @disk_start # create backing buffer and mem io buf = Bytes.new(len) io = MemoryIO.new(buf) - @file_size.to_u64.to_io(io, LE) + @size.to_u64.to_io(io, LE) @compressed_size.to_u64.to_io(io, LE) @pos.not_nil!.to_u64.to_io(io, LE) if @pos @disk_start.not_nil!.to_u32.to_io(io, LE) if @disk_start @@ -1719,7 +1726,7 @@ module Zip # create memory io over buffer io = MemoryIO.new(data, false) - @file_size = UInt64.from_io(io, LE).as(UInt64) + @size = UInt64.from_io(io, LE).as(UInt64) @compressed_size = UInt64.from_io(io, LE).as(UInt64) @pos, @disk_start = case data.size - 16 @@ -1758,18 +1765,12 @@ module Zip end # - # Static, zero-length `Bytes` when `Extra.pack()` is called with - # *nil* or an empty array. - # - EMPTY_EXTRAS = Bytes.new(0) - - # # Encode array of `Extra::Base` and return buffer. # def self.pack(extras : Array(Extra::Base)?) : Bytes if extras && extras.size > 0 # create backing buffer for extras - buf = Bytes.new(extras.reduce(0_u32) { |r, e| r + e.size }) + buf = Bytes.new(extras.reduce(0_u32) { |r, e| r + e.bytes_needed }) # create io and write each extra data to io io = MemoryIO.new(buf) @@ -1779,7 +1780,8 @@ module Zip # return buffer buf else - EMPTY_EXTRAS + # return empty slice + EMPTY_SLICE end end end @@ -1882,7 +1884,7 @@ module Zip getter :crc # - # Get compressed size for this `Entry` as a `UInt32`. + # Get compressed size for this `Entry`. # # Zip.read("foo.zip") do |zip| # # print compressed size for each entry @@ -1894,7 +1896,7 @@ module Zip getter :compressed_size # - # Get uncompressed size for this `Entry` as a `UInt32`. + # Get uncompressed size for this `Entry`. # # Zip.read("foo.zip") do |zip| # # print uncompressed size for each entry @@ -1966,7 +1968,7 @@ module Zip getter :external # - # Get position for this `Entry` as a `UInt32`. + # Get position for this `Entry`. # # Zip.read("foo.zip") do |zip| # # print position for each entry @@ -2040,9 +2042,10 @@ module Zip @time = from_dos_time(UInt32.from_io(head_mem_io, LE)).as(Time) # read crc and lengths + # (store lengths as u64 for zip64 compat) @crc = UInt32.from_io(head_mem_io, LE).as(UInt32) - @compressed_size = UInt32.from_io(head_mem_io, LE).as(UInt32) - @size = UInt32.from_io(head_mem_io, LE).as(UInt32) + @compressed_size = UInt32.from_io(head_mem_io, LE).to_u64.as(UInt64) + @size = UInt32.from_io(head_mem_io, LE).to_u64.as(UInt64) # read lengths @path_len = UInt16.from_io(head_mem_io, LE).not_nil!.as(UInt16) @@ -2050,12 +2053,16 @@ module Zip @comment_len = UInt16.from_io(head_mem_io, LE).as(UInt16) # read starting disk - @disk_start = UInt16.from_io(head_mem_io, LE).as(UInt16) + # (store as u32 for zip64 compat) + @disk_start = UInt16.from_io(head_mem_io, LE).to_u32.as(UInt32) # read attributes and position @internal = UInt16.from_io(head_mem_io, LE).as(UInt16) @external = UInt32.from_io(head_mem_io, LE).as(UInt32) - @pos = UInt32.from_io(head_mem_io, LE).as(UInt32) + + # read position + # (store as u64 for zip64 compat) + @pos = UInt32.from_io(head_mem_io, LE).to_u64.as(UInt64) # close memory io head_mem_io.close @@ -2076,6 +2083,14 @@ module Zip @extras = read_extras(data_mem_io, @extras_len) as Array(Extra::Base) @comment = read_string(data_mem_io, @comment_len, "comment") as String + if e = @extras.find { |e| e.code == Extra::Zip64::CODE } + e = e.as(Extra::Zip64) + @size = e.size + @compressed_size = e.compressed_size + @pos = e.pos.not_nil! if e.pos + @disk_start = e.disk_start.not_nil! if e.disk_start + end + # close data memory io data_mem_io.close end @@ -2127,7 +2142,7 @@ module Zip # end # end # - def write(dst_io : IO) : UInt32 + def write(dst_io : IO) : UInt64 # create buffer for local header buf = Bytes.new(30) @@ -2190,7 +2205,7 @@ module Zip # end # end # - def write(path : String) : UInt32 + def write(path : String) : UInt64 File.open(path, "wb") do |io| write(io) end @@ -2365,37 +2380,25 @@ module Zip mem_io = MemoryIO.new(mem, false) # read disk numbers - @disk_num = mem_io.read_bytes(UInt16, LE).as(UInt16) - @cdr_disk = mem_io.read_bytes(UInt16, LE).as(UInt16) - - # check disk numbers - if @disk_num != @cdr_disk - raise Error.new("multi-disk archives not supported") - end + # (convert to u32 so type matches zip64 values) + @disk_num = UInt16.from_io(mem_io, LE).to_u32.as(UInt32) + @cdr_disk = UInt16.from_io(mem_io, LE).to_u32.as(UInt32) # read entry counts - @num_disk_entries = mem_io.read_bytes(UInt16, LE).as(UInt16) - @num_entries = mem_io.read_bytes(UInt16, LE).not_nil!.as(UInt16) - - # check entry counts - if @num_disk_entries != @num_entries - raise Error.new("multi-disk archives not supported") - end + # (convert to u64 so type matches zip64 values) + @num_disk_entries = UInt16.from_io(mem_io, LE).to_u64.as(UInt64) + @num_entries = UInt16.from_io(mem_io, LE).to_u64.as(UInt64) # read cdr position and length - @cdr_len = mem_io.read_bytes(UInt32, LE).not_nil!.as(UInt32) - @cdr_pos = mem_io.read_bytes(UInt32, LE).not_nil!.as(UInt32) - - # check cdr position - if @cdr_pos.not_nil! + @cdr_len.not_nil! >= end_pos - raise Error.new("invalid CDR offset: #{@cdr_pos}") - end + # (convert to u64 so type matches zip64 values) + @cdr_len = UInt32.from_io(mem_io, LE).to_u64.as(UInt64) + @cdr_pos = UInt32.from_io(mem_io, LE).to_u64.as(UInt64) # read comment length and comment body - @comment_len = mem_io.read_bytes(UInt16, LE).not_nil!.as(UInt16) - @comment = if @comment_len.not_nil! > 0 + @comment_len = UInt16.from_io(mem_io, LE).as(UInt16) + @comment = if @comment_len > 0 # allocate space for comment - slice = Bytes.new(@comment_len.not_nil!) + slice = Bytes.new(@comment_len) # seek to comment position @io.pos = footer_pos + 22 @@ -2414,6 +2417,92 @@ module Zip # close memory io mem_io.close + # check and see if any of the footer entries are 0xFFFF or + # 0xFFFFFFFF (that is, they indicate a zip64 header) + if @disk_num == UInt16::MAX || @cdr_disk == UInt16::MAX || + @num_disk_entries == UInt16::MAX || @num_entries == UInt16::MAX || + @cdr_len == UInt32::MAX || @cdr_pos == UInt32::MAX + # create buffer and mem_io for zip64 header + buf = Bytes.new(56) + mem_io = MemoryIO.new(buf, false) + + # seek to zip64 footer position and read it in + z64_pos = find_zip64_footer(@io, footer_pos) + @io.read(buf) + + # read and check magic + magic = UInt32.from_io(mem_io, LE) + if magic != MAGIC[:z64_footer] + raise Error.new("invalid ZIP64 footer magic") + end + + # read zip64 footer length and calculate data len + # (footer length value excludes magic and length) + z64_len = UInt64.from_io(mem_io, LE) + @zip64_data_len = z64_len - 44 + + # read versions + @version = Version.new(UInt16.from_io(mem_io, LE)) + @version_needed = Version.new(UInt16.from_io(mem_io, LE)) + + # read disk numbers + @disk_num = UInt32.from_io(mem_io, LE).to_u32 + @cdr_disk = UInt32.from_io(mem_io, LE).to_u32 + + # read entry counts + @num_disk_entries = UInt64.from_io(mem_io, LE) + @num_entries = UInt64.from_io(mem_io, LE) + + # read cdr position and length + @cdr_len = UInt64.from_io(mem_io, LE) + @cdr_pos = UInt64.from_io(mem_io, LE) + + # close memory io + mem_io.close + + # read zip64 data + @zip64_data = if @zip64_data_len > 0 + # create buffer + z64_data_buf = Bytes.new(@zip64_data_len) + + # skip to data position and read it in + @io.pos = z64_pos + 56 + @io.read(z64_data_buf) + + # return buffer + z64_data_buf + else + EMPTY_SLICE + end + else + # set version and version_needed to default + @version = Version::DEFAULT + @version_needed = Version::DEFAULT + + # no zip64 data for non-zip64 archives + @zip64_data_len = 0_u64 + @zip64_data = EMPTY_SLICE + end + + ######################## + # verify header values # + ######################## + + # check disk numbers + if @disk_num != @cdr_disk + raise Error.new("multi-disk archives not supported") + end + + # check entry counts + if @num_disk_entries != @num_entries + raise Error.new("multi-disk archives not supported") + end + + # check cdr position + if @cdr_pos + @cdr_len >= end_pos + raise Error.new("invalid CDR offset: #{@cdr_pos}") + end + # read entries @entries = [] of Entry read_entries(@entries, @io, @cdr_pos, @cdr_len, @num_entries) @@ -2525,9 +2614,9 @@ module Zip private def read_entries( entries : Array(Entry), io : Source, - cdr_pos : UInt32, - cdr_len : UInt32, - num_entries : UInt16, + cdr_pos : UInt64, + cdr_len : UInt64, + num_entries : UInt64, ) # get end position end_cdr_pos = cdr_pos + cdr_len @@ -2601,8 +2690,42 @@ module Zip # throw error raise Error.new("couldn't find end of central directory") end - end + private def find_zip64_footer(io : Source, footer_pos : Int) : UInt64 + buf = Bytes.new(20) + mem_io = MemoryIO.new(buf, false) + + curr_pos = footer_pos - 20 + while curr_pos >= 0 + # sek to current position and read it into buffer + io.pos = curr_pos + io.read(buf) + + # read what might be the zip64 locator magic + maybe_magic = UInt32.from_io(mem_io, LE) + + if maybe_magic == MAGIC[:z64_locator] + z64_start_disk = UInt32.from_io(mem_io, LE) + z64_pos = UInt64.from_io(mem_io, LE) + z64_num_disks = UInt32.from_io(mem_io, LE) + + # check disk counts + if z64_start_disk > 1 || z64_num_disks > 1 + raise Error.new("multi-disk ZIP64 archives not supported") + end + + # return position of zip64 footer + return z64_pos + end + + # step back one byte + curr_pos -= 1 + end + + # throw error + raise Error.new("couldn't find ZIP64 locator") + end + end # # Read Zip::Archive from seekable IO instance and pass it to the given |