| Current File : //proc/thread-self/root/opt/alt/ruby32/share/rubygems/rubygems/security/policy.rb |
# frozen_string_literal: true
require_relative "../user_interaction"
##
# 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 in
# Gem::Security::Policies.
class Gem::Security::Policy
include Gem::UserInteraction
attr_reader :name
attr_accessor :only_signed
attr_accessor :only_trusted
attr_accessor :verify_chain
attr_accessor :verify_data
attr_accessor :verify_root
attr_accessor :verify_signer
##
# Create a new Gem::Security::Policy object with the given mode and
# options.
def initialize(name, policy = {}, opt = {})
@name = name
@opt = opt
# Default to security
@only_signed = true
@only_trusted = true
@verify_chain = true
@verify_data = true
@verify_root = true
@verify_signer = true
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
##
# Verifies each certificate in +chain+ has signed the following certificate
# and is valid for the given +time+.
def check_chain(chain, time)
raise Gem::Security::Exception, "missing signing chain" unless chain
raise Gem::Security::Exception, "empty signing chain" if chain.empty?
begin
chain.each_cons 2 do |issuer, cert|
check_cert cert, issuer, time
end
true
rescue Gem::Security::Exception => e
raise Gem::Security::Exception, "invalid signing chain: #{e.message}"
end
end
##
# Verifies that +data+ matches the +signature+ created by +public_key+ and
# the +digest+ algorithm.
def check_data(public_key, digest, signature, data)
raise Gem::Security::Exception, "invalid signature" unless
public_key.verify digest, signature, data.digest
true
end
##
# Ensures that +signer+ is valid for +time+ and was signed by the +issuer+.
# If the +issuer+ is +nil+ no verification is performed.
def check_cert(signer, issuer, time)
raise Gem::Security::Exception, "missing signing certificate" unless
signer
message = "certificate #{signer.subject}"
if (not_before = signer.not_before) && not_before > time
raise Gem::Security::Exception,
"#{message} not valid before #{not_before}"
end
if (not_after = signer.not_after) && not_after < time
raise Gem::Security::Exception, "#{message} not valid after #{not_after}"
end
if issuer && !signer.verify(issuer.public_key)
raise Gem::Security::Exception,
"#{message} was not issued by #{issuer.subject}"
end
true
end
##
# Ensures the public key of +key+ matches the public key in +signer+
def check_key(signer, key)
unless signer && key
return true unless @only_signed
raise Gem::Security::Exception, "missing key or signature"
end
raise Gem::Security::Exception,
"certificate #{signer.subject} does not match the signing key" unless
signer.check_private_key(key)
true
end
##
# Ensures the root certificate in +chain+ is self-signed and valid for
# +time+.
def check_root(chain, time)
raise Gem::Security::Exception, "missing signing chain" unless chain
root = chain.first
raise Gem::Security::Exception, "missing root certificate" unless root
raise Gem::Security::Exception,
"root certificate #{root.subject} is not self-signed " +
"(issuer #{root.issuer})" if
root.issuer != root.subject
check_cert root, root, time
end
##
# Ensures the root of +chain+ has a trusted certificate in +trust_dir+ and
# the digests of the two certificates match according to +digester+
def check_trust(chain, digester, trust_dir)
raise Gem::Security::Exception, "missing signing chain" unless chain
root = chain.first
raise Gem::Security::Exception, "missing root certificate" unless root
path = Gem::Security.trust_dir.cert_path root
unless File.exist? path
message = "root cert #{root.subject} is not trusted".dup
message << " (root of signing cert #{chain.last.subject})" if
chain.length > 1
raise Gem::Security::Exception, message
end
save_cert = OpenSSL::X509::Certificate.new File.read path
save_dgst = digester.digest save_cert.public_key.to_pem
pkey_str = root.public_key.to_pem
cert_dgst = digester.digest pkey_str
raise Gem::Security::Exception,
"trusted root certificate #{root.subject} checksum " +
"does not match signing root certificate checksum" unless
save_dgst == cert_dgst
true
end
##
# Extracts the email or subject from +certificate+
def subject(certificate) # :nodoc:
certificate.extensions.each do |extension|
next unless extension.oid == "subjectAltName"
return extension.value
end
certificate.subject.to_s
end
def inspect # :nodoc:
("[Policy: %s - data: %p signer: %p chain: %p root: %p " +
"signed-only: %p trusted-only: %p]") % [
@name, @verify_chain, @verify_data, @verify_root, @verify_signer,
@only_signed, @only_trusted
]
end
##
# For +full_name+, verifies the certificate +chain+ is valid, the +digests+
# match the signatures +signatures+ created by the signer depending on the
# +policy+ settings.
#
# If +key+ is given it is used to validate the signing certificate.
def verify(chain, key = nil, digests = {}, signatures = {},
full_name = "(unknown)")
if signatures.empty?
if @only_signed
raise Gem::Security::Exception,
"unsigned gems are not allowed by the #{name} policy"
elsif digests.empty?
# lack of signatures is irrelevant if there is nothing to check
# against
else
alert_warning "#{full_name} is not signed"
return
end
end
opt = @opt
digester = Gem::Security.create_digest
trust_dir = opt[:trust_dir]
time = Time.now
_, signer_digests = digests.find do |algorithm, file_digests|
file_digests.values.first.name == Gem::Security::DIGEST_NAME
end
if @verify_data
raise Gem::Security::Exception, "no digests provided (probable bug)" if
signer_digests.nil? || signer_digests.empty?
else
signer_digests = {}
end
signer = chain.last
check_key signer, key if key
check_cert signer, nil, time if @verify_signer
check_chain chain, time if @verify_chain
check_root chain, time if @verify_root
if @only_trusted
check_trust chain, digester, trust_dir
elsif signatures.empty? && digests.empty?
# trust is irrelevant if there's no signatures to verify
else
alert_warning "#{subject signer} is not trusted for #{full_name}"
end
signatures.each do |file, _|
digest = signer_digests[file]
raise Gem::Security::Exception, "missing digest for #{file}" unless
digest
end
signer_digests.each do |file, digest|
signature = signatures[file]
raise Gem::Security::Exception, "missing signature for #{file}" unless
signature
check_data signer.public_key, digester, signature, digest if @verify_data
end
true
end
##
# Extracts the certificate chain from the +spec+ and calls #verify to ensure
# the signatures and certificate chain is valid according to the policy..
def verify_signatures(spec, digests, signatures)
chain = spec.cert_chain.map do |cert_pem|
OpenSSL::X509::Certificate.new cert_pem
end
verify chain, nil, digests, signatures, spec.full_name
true
end
alias to_s name # :nodoc:
end