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|
#++
# Copyright (C) 2004 Mauricio Julio Fernández Pradier
# See LICENSE.txt for additional licensing information.
#--
require 'fileutils'
require 'find'
require 'stringio'
require 'yaml'
require 'zlib'
require 'rubygems/digest/md5'
require 'rubygems/security'
require 'rubygems/specification'
# Wrapper for FileUtils meant to provide logging and additional operations if
# needed.
class Gem::FileOperations
def initialize(logger = nil)
@logger = logger
end
def method_missing(meth, *args, &block)
case
when FileUtils.respond_to?(meth)
@logger.log "#{meth}: #{args}" if @logger
FileUtils.send meth, *args, &block
when Gem::FileOperations.respond_to?(meth)
@logger.log "#{meth}: #{args}" if @logger
Gem::FileOperations.send meth, *args, &block
else
super
end
end
end
module Gem::Package
class Error < StandardError; end
class NonSeekableIO < Error; end
class ClosedIO < Error; end
class BadCheckSum < Error; end
class TooLongFileName < Error; end
class FormatError < Error; end
module FSyncDir
private
def fsync_dir(dirname)
# make sure this hits the disc
begin
dir = open(dirname, "r")
dir.fsync
rescue # ignore IOError if it's an unpatched (old) Ruby
ensure
dir.close if dir rescue nil
end
end
end
class TarHeader
FIELDS = [:name, :mode, :uid, :gid, :size, :mtime, :checksum, :typeflag,
:linkname, :magic, :version, :uname, :gname, :devmajor,
:devminor, :prefix]
FIELDS.each {|x| attr_reader x}
def self.new_from_stream(stream)
data = stream.read(512)
fields = data.unpack("A100" + # record name
"A8A8A8" + # mode, uid, gid
"A12A12" + # size, mtime
"A8A" + # checksum, typeflag
"A100" + # linkname
"A6A2" + # magic, version
"A32" + # uname
"A32" + # gname
"A8A8" + # devmajor, devminor
"A155") # prefix
name = fields.shift
mode = fields.shift.oct
uid = fields.shift.oct
gid = fields.shift.oct
size = fields.shift.oct
mtime = fields.shift.oct
checksum = fields.shift.oct
typeflag = fields.shift
linkname = fields.shift
magic = fields.shift
version = fields.shift.oct
uname = fields.shift
gname = fields.shift
devmajor = fields.shift.oct
devminor = fields.shift.oct
prefix = fields.shift
empty = (data == "\0" * 512)
new(:name=>name, :mode=>mode, :uid=>uid, :gid=>gid, :size=>size,
:mtime=>mtime, :checksum=>checksum, :typeflag=>typeflag,
:magic=>magic, :version=>version, :uname=>uname, :gname=>gname,
:devmajor=>devmajor, :devminor=>devminor, :prefix=>prefix,
:empty => empty )
end
def initialize(vals)
unless vals[:name] && vals[:size] && vals[:prefix] && vals[:mode]
raise ArgumentError, ":name, :size, :prefix and :mode required"
end
vals[:uid] ||= 0
vals[:gid] ||= 0
vals[:mtime] ||= 0
vals[:checksum] ||= ""
vals[:typeflag] ||= "0"
vals[:magic] ||= "ustar"
vals[:version] ||= "00"
vals[:uname] ||= "wheel"
vals[:gname] ||= "wheel"
vals[:devmajor] ||= 0
vals[:devminor] ||= 0
FIELDS.each {|x| instance_variable_set "@#{x.to_s}", vals[x]}
@empty = vals[:empty]
end
def empty?
@empty
end
def to_s
update_checksum
header(checksum)
end
def update_checksum
h = header(" " * 8)
@checksum = oct(calculate_checksum(h), 6)
end
private
def oct(num, len)
"%0#{len}o" % num
end
def calculate_checksum(hdr)
hdr.unpack("C*").inject{|a,b| a+b}
end
def header(chksum)
# struct tarfile_entry_posix {
# char name[100]; # ASCII + (Z unless filled)
# char mode[8]; # 0 padded, octal, null
# char uid[8]; # ditto
# char gid[8]; # ditto
# char size[12]; # 0 padded, octal, null
# char mtime[12]; # 0 padded, octal, null
# char checksum[8]; # 0 padded, octal, null, space
# char typeflag[1]; # file: "0" dir: "5"
# char linkname[100]; # ASCII + (Z unless filled)
# char magic[6]; # "ustar\0"
# char version[2]; # "00"
# char uname[32]; # ASCIIZ
# char gname[32]; # ASCIIZ
# char devmajor[8]; # 0 padded, octal, null
# char devminor[8]; # o padded, octal, null
# char prefix[155]; # ASCII + (Z unless filled)
# };
arr = [name, oct(mode, 7), oct(uid, 7), oct(gid, 7), oct(size, 11),
oct(mtime, 11), chksum, " ", typeflag, linkname, magic, version,
uname, gname, oct(devmajor, 7), oct(devminor, 7), prefix]
str = arr.pack("a100a8a8a8a12a12" + # name, mode, uid, gid, size, mtime
"a7aaa100a6a2" + # chksum, typeflag, linkname, magic, version
"a32a32a8a8a155") # uname, gname, devmajor, devminor, prefix
str + "\0" * ((512 - str.size) % 512)
end
end
class TarWriter
class FileOverflow < StandardError; end
class BlockNeeded < StandardError; end
class BoundedStream
attr_reader :limit, :written
def initialize(io, limit)
@io = io
@limit = limit
@written = 0
end
def write(data)
if data.size + @written > @limit
raise FileOverflow,
"You tried to feed more data than fits in the file."
end
@io.write data
@written += data.size
data.size
end
end
class RestrictedStream
def initialize(anIO)
@io = anIO
end
def write(data)
@io.write data
end
end
def self.new(anIO)
writer = super(anIO)
return writer unless block_given?
begin
yield writer
ensure
writer.close
end
nil
end
def initialize(anIO)
@io = anIO
@closed = false
end
def add_file_simple(name, mode, size)
raise BlockNeeded unless block_given?
raise ClosedIO if @closed
name, prefix = split_name(name)
header = TarHeader.new(:name => name, :mode => mode,
:size => size, :prefix => prefix).to_s
@io.write header
os = BoundedStream.new(@io, size)
yield os
#FIXME: what if an exception is raised in the block?
min_padding = size - os.written
@io.write("\0" * min_padding)
remainder = (512 - (size % 512)) % 512
@io.write("\0" * remainder)
end
def add_file(name, mode)
raise BlockNeeded unless block_given?
raise ClosedIO if @closed
raise NonSeekableIO unless @io.respond_to? :pos=
name, prefix = split_name(name)
init_pos = @io.pos
@io.write "\0" * 512 # placeholder for the header
yield RestrictedStream.new(@io)
#FIXME: what if an exception is raised in the block?
#FIXME: what if an exception is raised in the block?
size = @io.pos - init_pos - 512
remainder = (512 - (size % 512)) % 512
@io.write("\0" * remainder)
final_pos = @io.pos
@io.pos = init_pos
header = TarHeader.new(:name => name, :mode => mode,
:size => size, :prefix => prefix).to_s
@io.write header
@io.pos = final_pos
end
def mkdir(name, mode)
raise ClosedIO if @closed
name, prefix = split_name(name)
header = TarHeader.new(:name => name, :mode => mode, :typeflag => "5",
:size => 0, :prefix => prefix).to_s
@io.write header
nil
end
def flush
raise ClosedIO if @closed
@io.flush if @io.respond_to? :flush
end
def close
#raise ClosedIO if @closed
return if @closed
@io.write "\0" * 1024
@closed = true
end
private
def split_name name
raise TooLongFileName if name.size > 256
if name.size <= 100
prefix = ""
else
parts = name.split(/\//)
newname = parts.pop
nxt = ""
loop do
nxt = parts.pop
break if newname.size + 1 + nxt.size > 100
newname = nxt + "/" + newname
end
prefix = (parts + [nxt]).join "/"
name = newname
raise TooLongFileName if name.size > 100 || prefix.size > 155
end
return name, prefix
end
end
class TarReader
include Gem::Package
class UnexpectedEOF < StandardError; end
module InvalidEntry
def read(len=nil); raise ClosedIO; end
def getc; raise ClosedIO; end
def rewind; raise ClosedIO; end
end
class Entry
TarHeader::FIELDS.each{|x| attr_reader x}
def initialize(header, anIO)
@io = anIO
@name = header.name
@mode = header.mode
@uid = header.uid
@gid = header.gid
@size = header.size
@mtime = header.mtime
@checksum = header.checksum
@typeflag = header.typeflag
@linkname = header.linkname
@magic = header.magic
@version = header.version
@uname = header.uname
@gname = header.gname
@devmajor = header.devmajor
@devminor = header.devminor
@prefix = header.prefix
@read = 0
@orig_pos = @io.pos
end
def read(len = nil)
return nil if @read >= @size
len ||= @size - @read
max_read = [len, @size - @read].min
ret = @io.read(max_read)
@read += ret.size
ret
end
def getc
return nil if @read >= @size
ret = @io.getc
@read += 1 if ret
ret
end
def is_directory?
@typeflag == "5"
end
def is_file?
@typeflag == "0"
end
def eof?
@read >= @size
end
def pos
@read
end
def rewind
raise NonSeekableIO unless @io.respond_to? :pos=
@io.pos = @orig_pos
@read = 0
end
alias_method :is_directory, :is_directory?
alias_method :is_file, :is_file?
def bytes_read
@read
end
def full_name
if @prefix != ""
File.join(@prefix, @name)
else
@name
end
end
def close
invalidate
end
private
def invalidate
extend InvalidEntry
end
end
def self.new(anIO)
reader = super(anIO)
return reader unless block_given?
begin
yield reader
ensure
reader.close
end
nil
end
def initialize(anIO)
@io = anIO
@init_pos = anIO.pos
end
def each(&block)
each_entry(&block)
end
# do not call this during a #each or #each_entry iteration
def rewind
if @init_pos == 0
raise NonSeekableIO unless @io.respond_to? :rewind
@io.rewind
else
raise NonSeekableIO unless @io.respond_to? :pos=
@io.pos = @init_pos
end
end
def each_entry
loop do
return if @io.eof?
header = TarHeader.new_from_stream(@io)
return if header.empty?
entry = Entry.new header, @io
size = entry.size
yield entry
skip = (512 - (size % 512)) % 512
if @io.respond_to? :seek
# avoid reading...
@io.seek(size - entry.bytes_read, IO::SEEK_CUR)
else
pending = size - entry.bytes_read
while pending > 0
bread = @io.read([pending, 4096].min).size
raise UnexpectedEOF if @io.eof?
pending -= bread
end
end
@io.read(skip) # discard trailing zeros
# make sure nobody can use #read, #getc or #rewind anymore
entry.close
end
end
def close
end
end
class TarInput
include FSyncDir
include Enumerable
attr_reader :metadata
class << self; private :new end
def initialize(io, security_policy = nil)
@io = io
@tarreader = TarReader.new(@io)
has_meta = false
data_sig, meta_sig, data_dgst, meta_dgst = nil, nil, nil, nil
dgst_algo = security_policy ? Gem::Security::OPT[:dgst_algo] : nil
@tarreader.each do |entry|
case entry.full_name
when "metadata"
@metadata = load_gemspec(entry.read)
has_meta = true
break
when "metadata.gz"
begin
# if we have a security_policy, then pre-read the metadata file
# and calculate it's digest
sio = nil
if security_policy
Gem.ensure_ssl_available
sio = StringIO.new(entry.read)
meta_dgst = dgst_algo.digest(sio.string)
sio.rewind
end
gzis = Zlib::GzipReader.new(sio || entry)
# YAML wants an instance of IO
@metadata = load_gemspec(gzis)
has_meta = true
ensure
gzis.close unless gzis.nil?
end
when 'metadata.gz.sig'
meta_sig = entry.read
when 'data.tar.gz.sig'
data_sig = entry.read
when 'data.tar.gz'
if security_policy
Gem.ensure_ssl_available
data_dgst = dgst_algo.digest(entry.read)
end
end
end
if security_policy then
Gem.ensure_ssl_available
# map trust policy from string to actual class (or a serialized YAML
# file, if that exists)
if String === security_policy then
if Gem::Security::Policy.key? security_policy then
# load one of the pre-defined security policies
security_policy = Gem::Security::Policy[security_policy]
elsif File.exist? security_policy then
# FIXME: this doesn't work yet
security_policy = YAML.load File.read(security_policy)
else
raise Gem::Exception, "Unknown trust policy '#{security_policy}'"
end
end
if data_sig && data_dgst && meta_sig && meta_dgst then
# the user has a trust policy, and we have a signed gem
# file, so use the trust policy to verify the gem signature
begin
security_policy.verify_gem(data_sig, data_dgst, @metadata.cert_chain)
rescue Exception => e
raise "Couldn't verify data signature: #{e}"
end
begin
security_policy.verify_gem(meta_sig, meta_dgst, @metadata.cert_chain)
rescue Exception => e
raise "Couldn't verify metadata signature: #{e}"
end
elsif security_policy.only_signed
raise Gem::Exception, "Unsigned gem"
else
# FIXME: should display warning here (trust policy, but
# either unsigned or badly signed gem file)
end
end
@tarreader.rewind
@fileops = Gem::FileOperations.new
raise FormatError, "No metadata found!" unless has_meta
end
# Attempt to YAML-load a gemspec from the given _io_ parameter. Return
# nil if it fails.
def load_gemspec(io)
Gem::Specification.from_yaml(io)
rescue Gem::Exception
nil
end
def self.open(filename, security_policy = nil, &block)
open_from_io(File.open(filename, "rb"), security_policy, &block)
end
def self.open_from_io(io, security_policy = nil, &block)
raise "Want a block" unless block_given?
begin
is = new(io, security_policy)
yield is
ensure
is.close if is
end
end
def each(&block)
@tarreader.each do |entry|
next unless entry.full_name == "data.tar.gz"
is = zipped_stream(entry)
begin
TarReader.new(is) do |inner|
inner.each(&block)
end
ensure
is.close if is
end
end
@tarreader.rewind
end
# Return an IO stream for the zipped entry.
#
# NOTE: Originally this method used two approaches, Return a GZipReader
# directly, or read the GZipReader into a string and return a StringIO on
# the string. The string IO approach was used for versions of ZLib before
# 1.2.1 to avoid buffer errors on windows machines. Then we found that
# errors happened with 1.2.1 as well, so we changed the condition. Then
# we discovered errors occurred with versions as late as 1.2.3. At this
# point (after some benchmarking to show we weren't seriously crippling
# the unpacking speed) we threw our hands in the air and declared that
# this method would use the String IO approach on all platforms at all
# times. And that's the way it is.
def zipped_stream(entry)
# This is Jamis Buck's ZLib workaround. The original code is
# commented out while we evaluate this patch.
entry.read(10) # skip the gzip header
zis = Zlib::Inflate.new(-Zlib::MAX_WBITS)
is = StringIO.new(zis.inflate(entry.read))
# zis = Zlib::GzipReader.new entry
# dis = zis.read
# is = StringIO.new(dis)
ensure
zis.finish if zis
end
def extract_entry(destdir, entry, expected_md5sum = nil)
if entry.is_directory?
dest = File.join(destdir, entry.full_name)
if file_class.dir? dest
@fileops.chmod entry.mode, dest, :verbose=>false
else
@fileops.mkdir_p(dest, :mode => entry.mode, :verbose=>false)
end
fsync_dir dest
fsync_dir File.join(dest, "..")
return
end
# it's a file
md5 = Digest::MD5.new if expected_md5sum
destdir = File.join(destdir, File.dirname(entry.full_name))
@fileops.mkdir_p(destdir, :mode => 0755, :verbose=>false)
destfile = File.join(destdir, File.basename(entry.full_name))
@fileops.chmod(0600, destfile, :verbose=>false) rescue nil # Errno::ENOENT
file_class.open(destfile, "wb", entry.mode) do |os|
loop do
data = entry.read(4096)
break unless data
md5 << data if expected_md5sum
os.write(data)
end
os.fsync
end
@fileops.chmod(entry.mode, destfile, :verbose=>false)
fsync_dir File.dirname(destfile)
fsync_dir File.join(File.dirname(destfile), "..")
if expected_md5sum && expected_md5sum != md5.hexdigest
raise BadCheckSum
end
end
def close
@io.close
@tarreader.close
end
private
def file_class
File
end
end
class TarOutput
class << self; private :new end
def initialize(io)
@io = io
@external = TarWriter.new @io
end
def external_handle
@external
end
def self.open(filename, signer = nil, &block)
io = File.open(filename, "wb")
open_from_io(io, signer, &block)
nil
end
def self.open_from_io(io, signer = nil, &block)
outputter = new(io)
metadata = nil
set_meta = lambda{|x| metadata = x}
raise "Want a block" unless block_given?
begin
data_sig, meta_sig = nil, nil
outputter.external_handle.add_file("data.tar.gz", 0644) do |inner|
begin
sio = signer ? StringIO.new : nil
os = Zlib::GzipWriter.new(sio || inner)
TarWriter.new(os) do |inner_tar_stream|
klass = class << inner_tar_stream; self end
klass.send(:define_method, :metadata=, &set_meta)
block.call inner_tar_stream
end
ensure
os.flush
os.finish
#os.close
# if we have a signing key, then sign the data
# digest and return the signature
data_sig = nil
if signer
dgst_algo = Gem::Security::OPT[:dgst_algo]
dig = dgst_algo.digest(sio.string)
data_sig = signer.sign(dig)
inner.write(sio.string)
end
end
end
# if we have a data signature, then write it to the gem too
if data_sig
sig_file = 'data.tar.gz.sig'
outputter.external_handle.add_file(sig_file, 0644) do |os|
os.write(data_sig)
end
end
outputter.external_handle.add_file("metadata.gz", 0644) do |os|
begin
sio = signer ? StringIO.new : nil
gzos = Zlib::GzipWriter.new(sio || os)
gzos.write metadata
ensure
gzos.flush
gzos.finish
# if we have a signing key, then sign the metadata
# digest and return the signature
if signer
dgst_algo = Gem::Security::OPT[:dgst_algo]
dig = dgst_algo.digest(sio.string)
meta_sig = signer.sign(dig)
os.write(sio.string)
end
end
end
# if we have a metadata signature, then write to the gem as
# well
if meta_sig
sig_file = 'metadata.gz.sig'
outputter.external_handle.add_file(sig_file, 0644) do |os|
os.write(meta_sig)
end
end
ensure
outputter.close
end
nil
end
def close
@external.close
@io.close
end
end
#FIXME: refactor the following 2 methods
def self.open(dest, mode = "r", signer = nil, &block)
raise "Block needed" unless block_given?
case mode
when "r"
security_policy = signer
TarInput.open(dest, security_policy, &block)
when "w"
TarOutput.open(dest, signer, &block)
else
raise "Unknown Package open mode"
end
end
def self.open_from_io(io, mode = "r", signer = nil, &block)
raise "Block needed" unless block_given?
case mode
when "r"
security_policy = signer
TarInput.open_from_io(io, security_policy, &block)
when "w"
TarOutput.open_from_io(io, signer, &block)
else
raise "Unknown Package open mode"
end
end
def self.pack(src, destname, signer = nil)
TarOutput.open(destname, signer) do |outp|
dir_class.chdir(src) do
outp.metadata = (file_class.read("RPA/metadata") rescue nil)
find_class.find('.') do |entry|
case
when file_class.file?(entry)
entry.sub!(%r{\./}, "")
next if entry =~ /\ARPA\//
stat = File.stat(entry)
outp.add_file_simple(entry, stat.mode, stat.size) do |os|
file_class.open(entry, "rb") do |f|
os.write(f.read(4096)) until f.eof?
end
end
when file_class.dir?(entry)
entry.sub!(%r{\./}, "")
next if entry == "RPA"
outp.mkdir(entry, file_class.stat(entry).mode)
else
raise "Don't know how to pack this yet!"
end
end
end
end
end
class << self
def file_class
File
end
def dir_class
Dir
end
def find_class # HACK kill me
Find
end
end
end
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