scinote-web/config/initializers/paperclip.rb

269 lines
10 KiB
Ruby

if ENV['PAPERCLIP_HASH_SECRET'].nil?
puts "WARNING! Environment variable PAPERCLIP_HASH_SECRET must be set."
exit 1
end
Paperclip::Attachment.default_options.merge!({
hash_data: ':class/:attachment/:id/:style',
hash_secret: ENV['PAPERCLIP_HASH_SECRET'],
preserve_files: false,
url: '/system/:class/:attachment/:id_partition/:hash/:style/:filename'
})
if ENV['PAPERCLIP_STORAGE'] == "s3"
if ENV['S3_BUCKET'].nil? or ENV['AWS_REGION'].nil? or
ENV['AWS_ACCESS_KEY_ID'].nil? or ENV['AWS_SECRET_ACCESS_KEY'].nil?
puts "WARNING! Environment variables S3_BUCKET, AWS_REGION, " +
"AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY must be set."
exit 1
end
Paperclip::Attachment.default_options.merge!({
url: ':s3_domain_url',
path: '/:class/:attachment/:id_partition/:hash/:style/:filename',
storage: :s3,
s3_host_name: "s3.#{ENV['AWS_REGION']}.amazonaws.com",
s3_protocol: 'https',
s3_credentials: {
bucket: ENV['S3_BUCKET'],
access_key_id: ENV['AWS_ACCESS_KEY_ID'],
secret_access_key: ENV['AWS_SECRET_ACCESS_KEY']
},
s3_permissions: {
original: :private,
medium: :private
},
s3_storage_class: {
medium: :reduced_redundancy,
thumb: :reduced_redundancy,
icon: :reduced_redundancy,
icon_small: :reduced_redundancy
}
})
elsif ENV['PAPERCLIP_STORAGE'] == "filesystem"
Paperclip::Attachment.default_options.merge!({
storage: :filesystem
})
end
Paperclip::Attachment.class_eval do
def is_stored_on_s3?
options[:storage].to_sym == :s3
end
def fetch
Paperclip.io_adapters.for self
end
end
module Paperclip
# Checks file for spoofing
class MediaTypeSpoofDetector
def spoofed?
if has_name? && has_extension? && (media_type_mismatch? ||
mapping_override_mismatch?)
Paperclip.log("Content Type Spoof: Filename #{File.basename(@name)} "\
"(#{supplied_content_type} from Headers, #{content_types_from_name} "\
"from Extension), content type discovered: "\
"#{calculated_content_type}. See documentation to allow this "\
"combination.")
true
else
false
end
end
private
# Determine file content type from its name
def content_types_from_name
@content_types_from_name ||=
Paperclip.run('mimetype', '-b :file_name', file_name: @name).chomp
end
# Determine file media type from its name
def media_types_from_name
@media_types_from_name ||= extract_media_type content_types_from_name
end
# Determine file content type from mimetype command
def type_from_mimetype_command
@type_from_mimetype_command ||=
Paperclip.run('mimetype', '-b :file', file: @file.path).chomp
end
# Determine file media type from mimetype command
def media_type_from_mimetype_command
@media_type_from_mimetype_command ||=
extract_media_type type_from_mimetype_command
end
# Determine file content type from it's content (file and mimetype command)
def type_from_file_command
unless defined? @type_from_file_command
@type_from_file_command =
Paperclip.run('file', '-b --mime :file', file: @file.path)
.split(/[:;]\s+/).first
if allowed_spoof_exception?(@type_from_file_command,
media_type_from_file_command) ||
(@type_from_file_command.in?(%w(text/plain text/html)) &&
media_type_from_mimetype_command.in?(%w(text application)))
# File content type is generalized, so rely on file extension for
# correct/more specific content type
@type_from_file_command = type_from_mimetype_command
end
end
@type_from_file_command
rescue Cocaine::CommandLineError
''
end
# Determine file media type from it's content (file and mimetype command)
def media_type_from_file_command
@media_type_from_file_command ||=
extract_media_type type_from_file_command
end
def extract_media_type(content_type)
if content_type.empty?
''
else
content_type.split('/').first
end
end
def media_type_mismatch?
calculated_type_mismatch?
end
# Checks file media type mismatch between file's name and header
# NOTE: Can't rely on headers, as different OS can have different file type
# MIME mappings
def supplied_type_mismatch?
!allowed_spoof_exception?(supplied_content_type, supplied_media_type) &&
media_types_from_name != supplied_media_type
end
# Checks file media type mismatch between file's name and content
def calculated_type_mismatch?
!allowed_spoof_exception?(calculated_content_type,
calculated_media_type) &&
media_types_from_name != calculated_media_type
end
# Checks file content type mismatch between file's name and content
def mapping_override_mismatch?
!allowed_spoof_exception?(calculated_content_type,
calculated_media_type) &&
content_types_from_name != calculated_content_type
end
# Check if we have a file spoof exception which is allowed/safe
def allowed_spoof_exception?(content_type, media_type)
content_type == 'application/octet-stream' ||
(content_type == 'inode/x-empty' && @file.size.zero?) ||
(content_type == 'text/x-c' &&
content_types_from_name == 'text/x-java') ||
(media_type.in?(%w(image audio video)) &&
media_type == media_types_from_name) ||
(content_types_from_name.in? %W(#{}
text/plain
application/octet-stream)) ||
# Types taken from: http://filext.com/faq/office_mime_types.php and
# https://www.openoffice.org/framework/documentation/mimetypes/mimetypes.html
#
# Generic application
(Set[content_type, content_types_from_name].subset? Set.new %w(
text/rtf
application/rtf
)) ||
# Word processor application
(Set[content_type, content_types_from_name].subset? Set.new %w(
application/vnd.ms-office
application/msword
application/msword-template
application/vnd.openxmlformats-officedocument.wordprocessingml.document
application/vnd.openxmlformats-officedocument.wordprocessingml.template
application/vnd.ms-word.document.macroEnabled.12
application/vnd.ms-word.template.macroEnabled.12
application/vnd.oasis.opendocument.text
application/vnd.oasis.opendocument.text-template
application/vnd.oasis.opendocument.text-web
application/vnd.oasis.opendocument.text-master
application/vnd.sun.xml.writer
application/vnd.sun.xml.writer.template
application/vnd.sun.xml.writer.global
application/vnd.stardivision.writer
application/vnd.stardivision.writer-global
application/x-starwriter
)) ||
# Spreadsheet application
(Set[content_type, content_types_from_name].subset? Set.new %w(
application/zip
application/vnd.ms-office
application/vnd.ms-excel
application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
application/vnd.openxmlformats-officedocument.spreadsheetml.template
application/vnd.ms-excel.sheet.macroEnabled.12
application/vnd.ms-excel.template.macroEnabled.12
application/vnd.ms-excel.addin.macroEnabled.12
application/vnd.ms-excel.sheet.binary.macroEnabled.12
application/vnd.oasis.opendocument.spreadsheet
application/vnd.oasis.opendocument.spreadsheet-template
application/vnd.sun.xml.calc
application/vnd.sun.xml.calc.template
application/vnd.stardivision.calc
application/x-starcalc
)) ||
# Presentation application
(Set[content_type, content_types_from_name].subset? Set.new %w(
application/vnd.ms-office
application/vnd.ms-powerpoint
application/vnd.openxmlformats-officedocument.presentationml.presentation
application/vnd.openxmlformats-officedocument.presentationml.template
application/vnd.openxmlformats-officedocument.presentationml.slideshow
application/vnd.ms-powerpoint.addin.macroEnabled.12
application/vnd.ms-powerpoint.presentation.macroEnabled.12
application/vnd.ms-powerpoint.template.macroEnabled.12
application/vnd.ms-powerpoint.slideshow.macroEnabled.12
application/vnd.oasis.opendocument.presentation
application/vnd.oasis.opendocument.presentation-template
application/vnd.sun.xml.impress
application/vnd.sun.xml.impress.template
application/vnd.stardivision.impress
application/vnd.stardivision.impress-packed
application/x-starimpress
text/x-gettext-translation-template
)) ||
# Graphics application
(Set[content_type, content_types_from_name].subset? Set.new %w(
application/vnd.ms-office
application/vnd.oasis.opendocument.graphics
application/vnd.oasis.opendocument.graphics-template
application/vnd.sun.xml.draw
application/vnd.sun.xml.draw.template
application/vnd.stardivision.draw
application/x-stardraw
)) ||
# Formula application
(Set[content_type, content_types_from_name].subset? Set.new %w(
application/vnd.ms-office
application/vnd.oasis.opendocument.formula
application/vnd.sun.xml.math
application/vnd.stardivision.math
application/x-starmath
)) ||
# Chart application
(Set[content_type, content_types_from_name].subset? Set.new %w(
application/vnd.ms-office
application/vnd.oasis.opendocument.chart
application/vnd.stardivision.chart
application/x-starchart
))
end
end
end