# frozen_string_literal: true require 'openssl' require 'digest' module Gitlab module X509 class Signature include Gitlab::Utils::StrongMemoize attr_reader :signature_text, :signed_text, :created_at def initialize(signature_text, signed_text, email, created_at) @signature_text = signature_text @signed_text = signed_text @email = email @created_at = created_at end def x509_certificate return if certificate_attributes.nil? X509Certificate.safe_create!(certificate_attributes) unless verified_signature.nil? end def user User.find_by_any_email(@email) end def verified_signature strong_memoize(:verified_signature) { verified_signature? } end def verification_status return :unverified if x509_certificate.nil? || x509_certificate.revoked? if verified_signature && certificate_email == @email :verified else :unverified end end private def cert strong_memoize(:cert) do signer_certificate(p7) if valid_signature? end end def cert_store strong_memoize(:cert_store) do store = OpenSSL::X509::Store.new store.set_default_paths if Feature.enabled?(:x509_forced_cert_loading, type: :ops) # Forcibly load the default cert file because the OpenSSL library seemingly ignores it store.add_file(OpenSSL::X509::DEFAULT_CERT_FILE) if File.exist?(OpenSSL::X509::DEFAULT_CERT_FILE) end # valid_signing_time? checks the time attributes already # this flag is required, otherwise expired certificates would become # unverified when notAfter within certificate attribute is reached store.flags = OpenSSL::X509::V_FLAG_NO_CHECK_TIME store end end def p7 strong_memoize(:p7) do pkcs7_text = signature_text.sub('-----BEGIN SIGNED MESSAGE-----', '-----BEGIN PKCS7-----') pkcs7_text = pkcs7_text.sub('-----END SIGNED MESSAGE-----', '-----END PKCS7-----') OpenSSL::PKCS7.new(pkcs7_text) rescue nil end end def valid_signing_time? # rfc 5280 - 4.1.2.5 Validity # check if signed_time is within the time range (notBefore/notAfter) # non-rfc - git specific check: signed_time >= commit_time p7.signers[0].signed_time.between?(cert.not_before, cert.not_after) && p7.signers[0].signed_time >= created_at end def valid_signature? p7.verify([], cert_store, signed_text, OpenSSL::PKCS7::NOVERIFY) rescue nil end def verified_signature? # verify has multiple options but only a boolean return value # so first verify without certificate chain if valid_signature? if valid_signing_time? # verify with system certificate chain p7.verify([], cert_store, signed_text) else false end else nil end rescue nil end def signer_certificate(p7) p7.certificates.each do |cert| next if cert.serial != p7.signers[0].serial return cert end end def certificate_crl extension = get_certificate_extension('crlDistributionPoints') return if extension.nil? crl_url = nil extension.each_line do |line| break if crl_url line.split('URI:').each do |item| item.strip if item.start_with?("http") crl_url = item.strip break end end end crl_url end def get_certificate_extension(extension) ext = cert.extensions.detect { |ext| ext.oid == extension } ext&.value end def issuer_subject_key_identifier key_identifier = get_certificate_extension('authorityKeyIdentifier') return if key_identifier.nil? key_identifier.gsub("keyid:", "").delete!("\n") end def certificate_subject_key_identifier key_identifier = get_certificate_extension('subjectKeyIdentifier') return if key_identifier.nil? key_identifier end def certificate_issuer cert.issuer.to_s(OpenSSL::X509::Name::RFC2253) end def certificate_subject cert.subject.to_s(OpenSSL::X509::Name::RFC2253) end def certificate_email email = nil get_certificate_extension('subjectAltName').split(',').each do |item| if item.strip.start_with?("email") email = item.split('email:')[1] break end end return if email.nil? email end def x509_issuer return if verified_signature.nil? || issuer_subject_key_identifier.nil? || certificate_crl.nil? attributes = { subject_key_identifier: issuer_subject_key_identifier, subject: certificate_issuer, crl_url: certificate_crl } X509Issuer.safe_create!(attributes) unless verified_signature.nil? end def certificate_attributes return if verified_signature.nil? || certificate_subject_key_identifier.nil? || x509_issuer.nil? { subject_key_identifier: certificate_subject_key_identifier, subject: certificate_subject, email: certificate_email, serial_number: cert.serial.to_i, x509_issuer_id: x509_issuer.id } end end end end