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# Copyright 2006 by Chad Fowler, Rich Kilmer, Jim Weirich and others.
# All rights reserved.
# See LICENSE.txt for permissions.
#++
require 'rubygems/exceptions'
require 'rubygems/gem_openssl'
require 'fileutils'
#
# = Signed Gems README
#
# == Table of Contents
# * Overview
# * Walkthrough
# * Command-Line Options
# * OpenSSL Reference
# * Bugs/TODO
# * About the Author
#
# == Overview
#
# Gem::Security implements cryptographic signatures in RubyGems. The section
# below is a step-by-step guide to using signed gems and generating your own.
#
# == Walkthrough
#
# In order to start signing your gems, you'll need to build a private key and
# a self-signed certificate. Here's how:
#
# # build a private key and certificate for gemmaster@example.com
# $ gem cert --build gemmaster@example.com
#
# This could take anywhere from 5 seconds to 10 minutes, depending on the
# speed of your computer (public key algorithms aren't exactly the speediest
# crypto algorithms in the world). When it's finished, you'll see the files
# "gem-private_key.pem" and "gem-public_cert.pem" in the current directory.
#
# First things first: take the "gem-private_key.pem" file and move it
# somewhere private, preferably a directory only you have access to, a floppy
# (yuck!), a CD-ROM, or something comparably secure. Keep your private key
# hidden; if it's compromised, someone can sign packages as you (note: PKI has
# ways of mitigating the risk of stolen keys; more on that later).
#
# Now, let's sign an existing gem. I'll be using my Imlib2-Ruby bindings, but
# you can use whatever gem you'd like. Open up your existing gemspec file and
# add the following lines:
#
# # signing key and certificate chain
# s.signing_key = '/mnt/floppy/gem-private_key.pem'
# s.cert_chain = ['gem-public_cert.pem']
#
# (Be sure to replace "/mnt/floppy" with the ultra-secret path to your private
# key).
#
# After that, go ahead and build your gem as usual. Congratulations, you've
# just built your first signed gem! If you peek inside your gem file, you'll
# see a couple of new files have been added:
#
# $ tar tf tar tf Imlib2-Ruby-0.5.0.gem
# data.tar.gz
# data.tar.gz.sig
# metadata.gz
# metadata.gz.sig
#
# Now let's verify the signature. Go ahead and install the gem, but add the
# following options: "-P HighSecurity", like this:
#
# # install the gem with using the security policy "HighSecurity"
# $ sudo gem install Imlib2-Ruby-0.5.0.gem -P HighSecurity
#
# The -P option sets your security policy -- we'll talk about that in just a
# minute. Eh, what's this?
#
# Attempting local installation of 'Imlib2-Ruby-0.5.0.gem'
# ERROR: Error installing gem Imlib2-Ruby-0.5.0.gem[.gem]: Couldn't
# verify data signature: Untrusted Signing Chain Root: cert =
# '/CN=gemmaster/DC=example/DC=com', error = 'path
# "/root/.rubygems/trust/cert-15dbb43a6edf6a70a85d4e784e2e45312cff7030.pem"
# does not exist'
#
# The culprit here is the security policy. RubyGems has several different
# security policies. Let's take a short break and go over the security
# policies. Here's a list of the available security policies, and a brief
# description of each one:
#
# * NoSecurity - Well, no security at all. Signed packages are treated like
# unsigned packages.
# * LowSecurity - Pretty much no security. If a package is signed then
# RubyGems will make sure the signature matches the signing
# certificate, and that the signing certificate hasn't expired, but
# that's it. A malicious user could easily circumvent this kind of
# security.
# * MediumSecurity - Better than LowSecurity and NoSecurity, but still
# fallible. Package contents are verified against the signing
# certificate, and the signing certificate is checked for validity,
# and checked against the rest of the certificate chain (if you don't
# know what a certificate chain is, stay tuned, we'll get to that).
# The biggest improvement over LowSecurity is that MediumSecurity
# won't install packages that are signed by untrusted sources.
# Unfortunately, MediumSecurity still isn't totally secure -- a
# malicious user can still unpack the gem, strip the signatures, and
# distribute the gem unsigned.
# * HighSecurity - Here's the bugger that got us into this mess.
# The HighSecurity policy is identical to the MediumSecurity policy,
# except that it does not allow unsigned gems. A malicious user
# doesn't have a whole lot of options here; he can't modify the
# package contents without invalidating the signature, and he can't
# modify or remove signature or the signing certificate chain, or
# RubyGems will simply refuse to install the package. Oh well, maybe
# he'll have better luck causing problems for CPAN users instead :).
#
# So, the reason RubyGems refused to install our shiny new signed gem was
# because it was from an untrusted source. Well, my code is infallible
# (hah!), so I'm going to add myself as a trusted source.
#
# Here's how:
#
# # add trusted certificate
# gem cert --add gem-public_cert.pem
#
# I've added my public certificate as a trusted source. Now I can install
# packages signed my private key without any hassle. Let's try the install
# command above again:
#
# # install the gem with using the HighSecurity policy (and this time
# # without any shenanigans)
# $ sudo gem install Imlib2-Ruby-0.5.0.gem -P HighSecurity
#
# This time RubyGems should accept your signed package and begin installing.
# While you're waiting for RubyGems to work it's magic, have a look at some of
# the other security commands:
#
# Usage: gem cert [options]
#
# Options:
# -a, --add CERT Add a trusted certificate.
# -l, --list List trusted certificates.
# -r, --remove STRING Remove trusted certificates containing STRING.
# -b, --build EMAIL_ADDR Build private key and self-signed certificate
# for EMAIL_ADDR.
# -C, --certificate CERT Certificate for --sign command.
# -K, --private-key KEY Private key for --sign command.
# -s, --sign NEWCERT Sign a certificate with my key and certificate.
#
# (By the way, you can pull up this list any time you'd like by typing "gem
# cert --help")
#
# Hmm. We've already covered the "--build" option, and the "--add", "--list",
# and "--remove" commands seem fairly straightforward; they allow you to add,
# list, and remove the certificates in your trusted certificate list. But
# what's with this "--sign" option?
#
# To answer that question, let's take a look at "certificate chains", a
# concept I mentioned earlier. There are a couple of problems with
# self-signed certificates: first of all, self-signed certificates don't offer
# a whole lot of security. Sure, the certificate says Yukihiro Matsumoto, but
# how do I know it was actually generated and signed by matz himself unless he
# gave me the certificate in person?
#
# The second problem is scalability. Sure, if there are 50 gem authors, then
# I have 50 trusted certificates, no problem. What if there are 500 gem
# authors? 1000? Having to constantly add new trusted certificates is a
# pain, and it actually makes the trust system less secure by encouraging
# RubyGems users to blindly trust new certificates.
#
# Here's where certificate chains come in. A certificate chain establishes an
# arbitrarily long chain of trust between an issuing certificate and a child
# certificate. So instead of trusting certificates on a per-developer basis,
# we use the PKI concept of certificate chains to build a logical hierarchy of
# trust. Here's a hypothetical example of a trust hierarchy based (roughly)
# on geography:
#
#
# --------------------------
# | rubygems@rubyforge.org |
# --------------------------
# |
# -----------------------------------
# | |
# ---------------------------- -----------------------------
# | seattle.rb@zenspider.com | | dcrubyists@richkilmer.com |
# ---------------------------- -----------------------------
# | | | |
# --------------- ---------------- ----------- --------------
# | alf@seattle | | bob@portland | | pabs@dc | | tomcope@dc |
# --------------- ---------------- ----------- --------------
#
#
# Now, rather than having 4 trusted certificates (one for alf@seattle,
# bob@portland, pabs@dc, and tomecope@dc), a user could actually get by with 1
# certificate: the "rubygems@rubyforge.org" certificate. Here's how it works:
#
# I install "Alf2000-Ruby-0.1.0.gem", a package signed by "alf@seattle". I've
# never heard of "alf@seattle", but his certificate has a valid signature from
# the "seattle.rb@zenspider.com" certificate, which in turn has a valid
# signature from the "rubygems@rubyforge.org" certificate. Voila! At this
# point, it's much more reasonable for me to trust a package signed by
# "alf@seattle", because I can establish a chain to "rubygems@rubyforge.org",
# which I do trust.
#
# And the "--sign" option allows all this to happen. A developer creates
# their build certificate with the "--build" option, then has their
# certificate signed by taking it with them to their next regional Ruby meetup
# (in our hypothetical example), and it's signed there by the person holding
# the regional RubyGems signing certificate, which is signed at the next
# RubyConf by the holder of the top-level RubyGems certificate. At each point
# the issuer runs the same command:
#
# # sign a certificate with the specified key and certificate
# # (note that this modifies client_cert.pem!)
# $ gem cert -K /mnt/floppy/issuer-priv_key.pem -C issuer-pub_cert.pem
# --sign client_cert.pem
#
# Then the holder of issued certificate (in this case, our buddy
# "alf@seattle"), can start using this signed certificate to sign RubyGems.
# By the way, in order to let everyone else know about his new fancy signed
# certificate, "alf@seattle" would change his gemspec file to look like this:
#
# # signing key (still kept in an undisclosed location!)
# s.signing_key = '/mnt/floppy/alf-private_key.pem'
#
# # certificate chain (includes the issuer certificate now too)
# s.cert_chain = ['/home/alf/doc/seattlerb-public_cert.pem',
# '/home/alf/doc/alf_at_seattle-public_cert.pem']
#
# Obviously, this RubyGems trust infrastructure doesn't exist yet. Also, in
# the "real world" issuers actually generate the child certificate from a
# certificate request, rather than sign an existing certificate. And our
# hypothetical infrastructure is missing a certificate revocation system.
# These are that can be fixed in the future...
#
# I'm sure your new signed gem has finished installing by now (unless you're
# installing rails and all it's dependencies, that is ;D). At this point you
# should know how to do all of these new and interesting things:
#
# * build a gem signing key and certificate
# * modify your existing gems to support signing
# * adjust your security policy
# * modify your trusted certificate list
# * sign a certificate
#
# If you've got any questions, feel free to contact me at the email address
# below. The next couple of sections
#
#
# == Command-Line Options
#
# Here's a brief summary of the certificate-related command line options:
#
# gem install
# -P, --trust-policy POLICY Specify gem trust policy.
#
# gem cert
# -a, --add CERT Add a trusted certificate.
# -l, --list List trusted certificates.
# -r, --remove STRING Remove trusted certificates containing
# STRING.
# -b, --build EMAIL_ADDR Build private key and self-signed
# certificate for EMAIL_ADDR.
# -C, --certificate CERT Certificate for --sign command.
# -K, --private-key KEY Private key for --sign command.
# -s, --sign NEWCERT Sign a certificate with my key and
# certificate.
#
# A more detailed description of each options is available in the walkthrough
# above.
#
# == Manually verifying signatures
#
# In case you don't trust RubyGems you can verify gem signatures manually:
#
# 1. Fetch and unpack the gem
#
# gem fetch some_signed_gem
# tar -xf some_signed_gem-1.0.gem
#
# 2. Grab the public key from the gemspec
#
# gem spec some_signed_gem-1.0.gem cert_chain | \
# ruby -pe 'sub(/^ +/, "")' > public_key.crt
#
# 3. Generate a SHA1 hash of the data.tar.gz
#
# openssl dgst -sha1 < data.tar.gz > my.hash
#
# 4. Verify the signature
#
# openssl rsautl -verify -inkey public_key.crt -certin \
# -in data.tar.gz.sig > verified.hash
#
# 5. Compare your hash to the verified hash
#
# diff -s verified.hash my.hash
#
# 6. Repeat 5 and 6 with metadata.gz
#
# == OpenSSL Reference
#
# The .pem files generated by --build and --sign are just basic OpenSSL PEM
# files. Here's a couple of useful commands for manipulating them:
#
# # convert a PEM format X509 certificate into DER format:
# # (note: Windows .cer files are X509 certificates in DER format)
# $ openssl x509 -in input.pem -outform der -out output.der
#
# # print out the certificate in a human-readable format:
# $ openssl x509 -in input.pem -noout -text
#
# And you can do the same thing with the private key file as well:
#
# # convert a PEM format RSA key into DER format:
# $ openssl rsa -in input_key.pem -outform der -out output_key.der
#
# # print out the key in a human readable format:
# $ openssl rsa -in input_key.pem -noout -text
#
# == Bugs/TODO
#
# * There's no way to define a system-wide trust list.
# * custom security policies (from a YAML file, etc)
# * Simple method to generate a signed certificate request
# * Support for OCSP, SCVP, CRLs, or some other form of cert
# status check (list is in order of preference)
# * Support for encrypted private keys
# * Some sort of semi-formal trust hierarchy (see long-winded explanation
# above)
# * Path discovery (for gem certificate chains that don't have a self-signed
# root) -- by the way, since we don't have this, THE ROOT OF THE CERTIFICATE
# CHAIN MUST BE SELF SIGNED if Policy#verify_root is true (and it is for the
# MediumSecurity and HighSecurity policies)
# * Better explanation of X509 naming (ie, we don't have to use email
# addresses)
# * Possible alternate signing mechanisms (eg, via PGP). this could be done
# pretty easily by adding a :signing_type attribute to the gemspec, then add
# the necessary support in other places
# * Honor AIA field (see note about OCSP above)
# * Maybe honor restriction extensions?
# * Might be better to store the certificate chain as a PKCS#7 or PKCS#12
# file, instead of an array embedded in the metadata. ideas?
# * Possibly embed signature and key algorithms into metadata (right now
# they're assumed to be the same as what's set in Gem::Security::OPT)
#
# == About the Author
#
# Paul Duncan <pabs@pablotron.org>
# http://pablotron.org/
module Gem::Security
##
# Gem::Security default exception type
class Exception < Gem::Exception; end
##
# Default options for most of the methods below
OPT = {
# private key options
:key_algo => Gem::SSL::PKEY_RSA,
:key_size => 2048,
# public cert options
:cert_age => 365 * 24 * 3600, # 1 year
:dgst_algo => Gem::SSL::DIGEST_SHA1,
# x509 certificate extensions
:cert_exts => {
'basicConstraints' => 'CA:FALSE',
'subjectKeyIdentifier' => 'hash',
'keyUsage' => 'keyEncipherment,dataEncipherment,digitalSignature',
},
# save the key and cert to a file in build_self_signed_cert()?
:save_key => true,
:save_cert => true,
# if you define either of these, then they'll be used instead of
# the output_fmt macro below
:save_key_path => nil,
:save_cert_path => nil,
# output name format for self-signed certs
:output_fmt => 'gem-%s.pem',
:munge_re => Regexp.new(/[^a-z0-9_.-]+/),
# output directory for trusted certificate checksums
:trust_dir => File.join(Gem.user_home, '.gem', 'trust'),
# default permissions for trust directory and certs
:perms => {
:trust_dir => 0700,
:trusted_cert => 0600,
:signing_cert => 0600,
:signing_key => 0600,
},
}
##
# A Gem::Security::Policy object encapsulates the settings for verifying
# signed gem files. This is the base class. You can either declare an
# instance of this or use one of the preset security policies below.
class Policy
attr_accessor :verify_data, :verify_signer, :verify_chain,
:verify_root, :only_trusted, :only_signed
#
# Create a new Gem::Security::Policy object with the given mode and
# options.
#
def initialize(policy = {}, opt = {})
# set options
@opt = Gem::Security::OPT.merge(opt)
# build policy
policy.each_pair do |key, val|
case key
when :verify_data then @verify_data = val
when :verify_signer then @verify_signer = val
when :verify_chain then @verify_chain = val
when :verify_root then @verify_root = val
when :only_trusted then @only_trusted = val
when :only_signed then @only_signed = val
end
end
end
#
# Get the path to the file for this cert.
#
def self.trusted_cert_path(cert, opt = {})
opt = Gem::Security::OPT.merge(opt)
# get digest algorithm, calculate checksum of root.subject
algo = opt[:dgst_algo]
dgst = algo.hexdigest(cert.subject.to_s)
# build path to trusted cert file
name = "cert-#{dgst}.pem"
# join and return path components
File::join(opt[:trust_dir], name)
end
#
# Verify that the gem data with the given signature and signing chain
# matched this security policy at the specified time.
#
def verify_gem(signature, data, chain, time = Time.now)
Gem.ensure_ssl_available
cert_class = OpenSSL::X509::Certificate
exc = Gem::Security::Exception
chain ||= []
chain = chain.map{ |str| cert_class.new(str) }
signer, ch_len = chain[-1], chain.size
# make sure signature is valid
if @verify_data
# get digest algorithm (TODO: this should be configurable)
dgst = @opt[:dgst_algo]
# verify the data signature (this is the most important part, so don't
# screw it up :D)
v = signer.public_key.verify(dgst.new, signature, data)
raise exc, "Invalid Gem Signature" unless v
# make sure the signer is valid
if @verify_signer
# make sure the signing cert is valid right now
v = signer.check_validity(nil, time)
raise exc, "Invalid Signature: #{v[:desc]}" unless v[:is_valid]
end
end
# make sure the certificate chain is valid
if @verify_chain
# iterate down over the chain and verify each certificate against it's
# issuer
(ch_len - 1).downto(1) do |i|
issuer, cert = chain[i - 1, 2]
v = cert.check_validity(issuer, time)
raise exc, "%s: cert = '%s', error = '%s'" % [
'Invalid Signing Chain', cert.subject, v[:desc]
] unless v[:is_valid]
end
# verify root of chain
if @verify_root
# make sure root is self-signed
root = chain[0]
raise exc, "%s: %s (subject = '%s', issuer = '%s')" % [
'Invalid Signing Chain Root',
'Subject does not match Issuer for Gem Signing Chain',
root.subject.to_s,
root.issuer.to_s,
] unless root.issuer.to_s == root.subject.to_s
# make sure root is valid
v = root.check_validity(root, time)
raise exc, "%s: cert = '%s', error = '%s'" % [
'Invalid Signing Chain Root', root.subject, v[:desc]
] unless v[:is_valid]
# verify that the chain root is trusted
if @only_trusted
# get digest algorithm, calculate checksum of root.subject
algo = @opt[:dgst_algo]
path = Gem::Security::Policy.trusted_cert_path(root, @opt)
# check to make sure trusted path exists
raise exc, "%s: cert = '%s', error = '%s'" % [
'Untrusted Signing Chain Root',
root.subject.to_s,
"path \"#{path}\" does not exist",
] unless File.exist?(path)
# load calculate digest from saved cert file
save_cert = OpenSSL::X509::Certificate.new(File.read(path))
save_dgst = algo.digest(save_cert.public_key.to_s)
# create digest of public key
pkey_str = root.public_key.to_s
cert_dgst = algo.digest(pkey_str)
# now compare the two digests, raise exception
# if they don't match
raise exc, "%s: %s (saved = '%s', root = '%s')" % [
'Invalid Signing Chain Root',
"Saved checksum doesn't match root checksum",
save_dgst, cert_dgst,
] unless save_dgst == cert_dgst
end
end
# return the signing chain
chain.map { |cert| cert.subject }
end
end
end
##
# No security policy: all package signature checks are disabled.
NoSecurity = Policy.new(
:verify_data => false,
:verify_signer => false,
:verify_chain => false,
:verify_root => false,
:only_trusted => false,
:only_signed => false
)
##
# AlmostNo security policy: only verify that the signing certificate is the
# one that actually signed the data. Make no attempt to verify the signing
# certificate chain.
#
# This policy is basically useless. better than nothing, but can still be
# easily spoofed, and is not recommended.
AlmostNoSecurity = Policy.new(
:verify_data => true,
:verify_signer => false,
:verify_chain => false,
:verify_root => false,
:only_trusted => false,
:only_signed => false
)
##
# Low security policy: only verify that the signing certificate is actually
# the gem signer, and that the signing certificate is valid.
#
# This policy is better than nothing, but can still be easily spoofed, and
# is not recommended.
LowSecurity = Policy.new(
:verify_data => true,
:verify_signer => true,
:verify_chain => false,
:verify_root => false,
:only_trusted => false,
:only_signed => false
)
##
# Medium security policy: verify the signing certificate, verify the signing
# certificate chain all the way to the root certificate, and only trust root
# certificates that we have explicitly allowed trust for.
#
# This security policy is reasonable, but it allows unsigned packages, so a
# malicious person could simply delete the package signature and pass the
# gem off as unsigned.
MediumSecurity = Policy.new(
:verify_data => true,
:verify_signer => true,
:verify_chain => true,
:verify_root => true,
:only_trusted => true,
:only_signed => false
)
##
# High security policy: only allow signed gems to be installed, verify the
# signing certificate, verify the signing certificate chain all the way to
# the root certificate, and only trust root certificates that we have
# explicitly allowed trust for.
#
# This security policy is significantly more difficult to bypass, and offers
# a reasonable guarantee that the contents of the gem have not been altered.
HighSecurity = Policy.new(
:verify_data => true,
:verify_signer => true,
:verify_chain => true,
:verify_root => true,
:only_trusted => true,
:only_signed => true
)
##
# Hash of configured security policies
Policies = {
'NoSecurity' => NoSecurity,
'AlmostNoSecurity' => AlmostNoSecurity,
'LowSecurity' => LowSecurity,
'MediumSecurity' => MediumSecurity,
'HighSecurity' => HighSecurity,
}
##
# Sign the cert cert with @signing_key and @signing_cert, using the digest
# algorithm opt[:dgst_algo]. Returns the newly signed certificate.
def self.sign_cert(cert, signing_key, signing_cert, opt = {})
opt = OPT.merge(opt)
cert.issuer = signing_cert.subject
cert.sign signing_key, opt[:dgst_algo].new
cert
end
##
# Make sure the trust directory exists. If it does exist, make sure it's
# actually a directory. If not, then create it with the appropriate
# permissions.
def self.verify_trust_dir(path, perms)
# if the directory exists, then make sure it is in fact a directory. if
# it doesn't exist, then create it with the appropriate permissions
if File.exist?(path)
# verify that the trust directory is actually a directory
unless File.directory?(path)
err = "trust directory #{path} isn't a directory"
raise Gem::Security::Exception, err
end
else
# trust directory doesn't exist, so create it with permissions
FileUtils.mkdir_p(path)
FileUtils.chmod(perms, path)
end
end
##
# Build a certificate from the given DN and private key.
def self.build_cert(name, key, opt = {})
Gem.ensure_ssl_available
opt = OPT.merge opt
cert = OpenSSL::X509::Certificate.new
cert.not_after = Time.now + opt[:cert_age]
cert.not_before = Time.now
cert.public_key = key.public_key
cert.serial = 0
cert.subject = name
cert.version = 2
ef = OpenSSL::X509::ExtensionFactory.new nil, cert
cert.extensions = opt[:cert_exts].map do |ext_name, value|
ef.create_extension ext_name, value
end
i_key = opt[:issuer_key] || key
i_cert = opt[:issuer_cert] || cert
cert = sign_cert cert, i_key, i_cert, opt
cert
end
##
# Build a self-signed certificate for the given email address.
def self.build_self_signed_cert(email_addr, opt = {})
Gem.ensure_ssl_available
opt = OPT.merge(opt)
path = { :key => nil, :cert => nil }
name = email_to_name email_addr, opt[:munge_re]
key = opt[:key_algo].new opt[:key_size]
verify_trust_dir opt[:trust_dir], opt[:perms][:trust_dir]
if opt[:save_key] then
path[:key] = opt[:save_key_path] || (opt[:output_fmt] % 'private_key')
open path[:key], 'wb' do |io|
io.chmod opt[:perms][:signing_key]
io.write key.to_pem
end
end
cert = build_cert name, key, opt
if opt[:save_cert] then
path[:cert] = opt[:save_cert_path] || (opt[:output_fmt] % 'public_cert')
open path[:cert], 'wb' do |file|
file.chmod opt[:perms][:signing_cert]
file.write cert.to_pem
end
end
{ :key => key, :cert => cert,
:key_path => path[:key], :cert_path => path[:cert] }
end
##
# Turns +email_address+ into an OpenSSL::X509::Name
def self.email_to_name email_address, munge_re
cn, dcs = email_address.split '@'
dcs = dcs.split '.'
cn = cn.gsub munge_re, '_'
dcs = dcs.map do |dc|
dc.gsub munge_re, '_'
end
name = "CN=#{cn}/" << dcs.map { |dc| "DC=#{dc}" }.join('/')
OpenSSL::X509::Name.parse name
end
##
# Add certificate to trusted cert list.
#
# Note: At the moment these are stored in OPT[:trust_dir], although that
# directory may change in the future.
def self.add_trusted_cert(cert, opt = {})
opt = OPT.merge(opt)
# get destination path
path = Gem::Security::Policy.trusted_cert_path(cert, opt)
# verify trust directory (can't write to nowhere, you know)
verify_trust_dir(opt[:trust_dir], opt[:perms][:trust_dir])
# write cert to output file
File.open(path, 'wb') do |file|
file.chmod(opt[:perms][:trusted_cert])
file.write(cert.to_pem)
end
# return nil
nil
end
##
# Basic OpenSSL-based package signing class.
class Signer
attr_accessor :cert_chain
attr_accessor :key
def initialize(key, cert_chain)
Gem.ensure_ssl_available
@algo = Gem::Security::OPT[:dgst_algo]
@key, @cert_chain = key, cert_chain
# check key, if it's a file, and if it's key, leave it alone
if @key && !@key.kind_of?(OpenSSL::PKey::PKey)
@key = OpenSSL::PKey::RSA.new(File.read(@key))
end
# check cert chain, if it's a file, load it, if it's cert data, convert
# it into a cert object, and if it's a cert object, leave it alone
if @cert_chain
@cert_chain = @cert_chain.map do |cert|
# check cert, if it's a file, load it, if it's cert data, convert it
# into a cert object, and if it's a cert object, leave it alone
if cert && !cert.kind_of?(OpenSSL::X509::Certificate)
cert = File.read(cert) if File::exist?(cert)
cert = OpenSSL::X509::Certificate.new(cert)
end
cert
end
end
end
##
# Sign data with given digest algorithm
def sign(data)
@key.sign(@algo.new, data)
end
end
end
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