Stores tracking fingerprints if they exist

* Updates parsers/security/common.rb to parse the `tracking`
  field if it exists
* Adds PORO and model classes for FindingFingerprint:
  * ee/lib/gitlab/ci/reports/security/finding_fingerprint.rb
  * ee/app/models/vulnerabilities/finding_fingerprint.rb
* Updates ee/app/services/security/store_report_service.rb to save
  and update finding fingerprints when storing a report in the
  database
* Adds unit tests for the new classes
* Adds unit tests for store_report_service

changelogs/unreleased/improve_vuln_tracking-backend_store_only.yml

+---
+title: 'Improve Vulnerability Tracking: Store Fingerprints'
+merge_request: 55173
+author:
+type: added

db/migrate/20210218142626_change_finding_fingerprint_enum.rb

+# frozen_string_literal: true
+
+class ChangeFindingFingerprintEnum < ActiveRecord::Migration[6.0]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def up
+    change_column :vulnerability_finding_fingerprints, :algorithm_type, :integer, limit: 2
+  end
+
+  def down
+    change_column :vulnerability_finding_fingerprints, :algorithm_type, :integer
+  end
+end

db/schema_migrations/20210218142626

+063c97800eec5bfc7f6879dbe559fa39952295d5ba947cf44ad03ac23212e924
\ No newline at end of file

db/structure.sql

@@ -18258,7 +18258,7 @@ CREATE TABLE vulnerability_finding_fingerprints (
     finding_id bigint NOT NULL,
     created_at timestamp with time zone NOT NULL,
     updated_at timestamp with time zone NOT NULL,
-    algorithm_type integer NOT NULL,
+    algorithm_type smallint NOT NULL,
     fingerprint_sha256 bytea NOT NULL
 );
 

ee/app/models/vulnerabilities/finding.rb

@@ -34,6 +34,8 @@ module Vulnerabilities
     has_many :finding_pipelines, class_name: 'Vulnerabilities::FindingPipeline', inverse_of: :finding, foreign_key: 'occurrence_id'
     has_many :pipelines, through: :finding_pipelines, class_name: 'Ci::Pipeline'
 
+    has_many :fingerprints, class_name: 'Vulnerabilities::FindingFingerprint', inverse_of: :finding
+
     serialize :config_options, Serializers::JSON # rubocop:disable Cop/ActiveRecordSerialize
 
     attr_writer :sha

ee/app/models/vulnerabilities/finding_fingerprint.rb

+# frozen_string_literal: true
+
+module Vulnerabilities
+  class FindingFingerprint < ApplicationRecord
+    self.table_name = 'vulnerability_finding_fingerprints'
+
+    include BulkInsertSafe
+
+    belongs_to :finding, foreign_key: 'finding_id', inverse_of: :fingerprints, class_name: 'Vulnerabilities::Finding'
+
+    enum algorithm_type: { hash: 1, location: 2, scope_offset: 3 }, _prefix: :algorithm
+
+    validates :finding, presence: true
+  end
+end

ee/app/services/security/store_report_service.rb

@@ -57,6 +57,7 @@ module Security
 
       update_vulnerability_finding(vulnerability_finding, vulnerability_params)
       reset_remediations_for(vulnerability_finding, finding)
+      update_finding_fingerprints(finding, vulnerability_finding)
 
       # The maximum number of identifiers is not used in validation
       # we just want to ignore the rest if a finding has more than that.
@@ -170,6 +171,43 @@ module Security
     end
     # rubocop: enable CodeReuse/ActiveRecord
 
+    def update_finding_fingerprints(finding, vulnerability_finding)
+      to_update = {}
+      to_create = []
+
+      poro_fingerprints = finding.fingerprints.index_by(&:algorithm_type)
+
+      vulnerability_finding.fingerprints.each do |fingerprint|
+        # NOTE: index_by takes the last entry if there are duplicates of the same algorithm, which should never occur.
+        poro_fingerprint = poro_fingerprints[fingerprint.algorithm_type]
+
+        # We're no longer generating these types of fingerprints. Since
+        # we're updating the persisted vulnerability, no need to do anything
+        # with these fingerprints now. We will track growth with
+        # https://gitlab.com/gitlab-org/gitlab/-/issues/322186
+        next if poro_fingerprint.nil?
+
+        poro_fingerprints.delete(fingerprint.algorithm_type)
+        to_update[fingerprint.id] = poro_fingerprint.to_h
+      end
+
+      # any remaining poro fingerprints left are new
+      poro_fingerprints.values.each do |poro_fingerprint|
+        attributes = poro_fingerprint.to_h.merge(finding_id: vulnerability_finding.id)
+        to_create << ::Vulnerabilities::FindingFingerprint.new(attributes: attributes, created_at: Time.zone.now, updated_at: Time.zone.now)
+      end
+
+      ::Vulnerabilities::FindingFingerprint.transaction do
+        if to_update.count > 0
+          ::Vulnerabilities::FindingFingerprint.update(to_update.keys, to_update.values)
+        end
+
+        if to_create.count > 0
+          ::Vulnerabilities::FindingFingerprint.bulk_insert!(to_create)
+        end
+      end
+    end
+
     def create_vulnerability(vulnerability_finding, pipeline)
       if vulnerability_finding.vulnerability_id
         Vulnerabilities::UpdateService.new(vulnerability_finding.project, pipeline.user, finding: vulnerability_finding, resolved_on_default_branch: false).execute

ee/lib/gitlab/ci/parsers/security/common.rb

@@ -71,11 +71,16 @@ module Gitlab
             end
           end
 
+          def tracking_data(data)
+            data['tracking']
+          end
+
           def create_vulnerability(data)
             identifiers = create_identifiers(data['identifiers'])
             links = create_links(data['links'])
             location = create_location(data['location'] || {})
             remediations = create_remediations(data['remediations'])
+            fingerprints = create_fingerprints(tracking_data(data))
 
             report.add_finding(
               ::Gitlab::Ci::Reports::Security::Finding.new(
@@ -93,7 +98,36 @@ module Gitlab
                 remediations: remediations,
                 raw_metadata: data.to_json,
                 metadata_version: report_version,
-                details: data['details'] || {}))
+                details: data['details'] || {},
+                fingerprints: fingerprints))
+          end
+
+          def create_fingerprints(tracking)
+            return [] if tracking.nil? || tracking['items'].nil?
+
+            fingerprint_algorithms = Hash.new { |hash, key| hash[key] = [] }
+            tracking['items'].each do |item|
+              next unless item.key?('fingerprints')
+
+              item['fingerprints'].each do |fingerprint|
+                alg = fingerprint['algorithm']
+                fingerprint_algorithms[alg] << fingerprint['value']
+              end
+            end
+
+            fingerprint_algorithms.map do |algorithm, values|
+              value = values.join('|')
+              begin
+                fingerprint = ::Gitlab::Ci::Reports::Security::FindingFingerprint.new(
+                  algorithm_type: algorithm,
+                  fingerprint_value: value
+                )
+                fingerprint.valid? ? fingerprint : nil
+              rescue ArgumentError => e
+                Gitlab::ErrorTracking.track_and_raise_for_dev_exception(e)
+                nil
+              end
+            end.compact
           end
 
           def create_scan

ee/lib/gitlab/ci/reports/security/finding.rb

@@ -24,10 +24,11 @@ module Gitlab
           attr_reader :uuid
           attr_reader :remediations
           attr_reader :details
+          attr_reader :fingerprints
 
           delegate :file_path, :start_line, :end_line, to: :location
 
-          def initialize(compare_key:, identifiers:, links: [], remediations: [], location:, metadata_version:, name:, raw_metadata:, report_type:, scanner:, scan:, uuid:, confidence: nil, severity: nil, details: {}) # rubocop:disable Metrics/ParameterLists
+          def initialize(compare_key:, identifiers:, links: [], remediations: [], location:, metadata_version:, name:, raw_metadata:, report_type:, scanner:, scan:, uuid:, confidence: nil, severity: nil, details: {}, fingerprints: []) # rubocop:disable Metrics/ParameterLists
             @compare_key = compare_key
             @confidence = confidence
             @identifiers = identifiers
@@ -43,6 +44,7 @@ module Gitlab
             @uuid = uuid
             @remediations = remediations
             @details = details
+            @fingerprints = fingerprints
 
             @project_fingerprint = generate_project_fingerprint
           end

ee/lib/gitlab/ci/reports/security/finding_fingerprint.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module Ci
+    module Reports
+      module Security
+        class FindingFingerprint
+          attr_accessor :algorithm_type, :fingerprint_value
+
+          def initialize(params = {})
+            @algorithm_type = params.dig(:algorithm_type)
+            @fingerprint_value = params.dig(:fingerprint_value)
+          end
+
+          def fingerprint_sha256
+            Digest::SHA1.digest(fingerprint_value)
+          end
+
+          def to_h
+            {
+              algorithm_type: algorithm_type,
+              fingerprint_sha256: fingerprint_sha256
+            }
+          end
+
+          def valid?
+            ::Vulnerabilities::FindingFingerprint.algorithm_types.key?(algorithm_type)
+          end
+        end
+      end
+    end
+  end
+end

ee/spec/factories/vulnerabilities/finding_fingerprints.rb

+# frozen_string_literal: true
+
+FactoryBot.define do
+  factory :vulnerabilities_finding_fingerprint, class: 'Vulnerabilities::FindingFingerprint' do
+    finding factory: :vulnerabilities_finding
+    algorithm_type { ::Vulnerabilities::FindingFingerprint.algorithm_types[:hash] }
+    fingerprint_sha256 { ::Digest::SHA1.digest(SecureRandom.hex(50)) }
+  end
+end

ee/spec/lib/gitlab/ci/parsers/security/common_spec.rb

@@ -9,12 +9,24 @@ RSpec.describe Gitlab::Ci::Parsers::Security::Common do
     let(:artifact) { build(:ee_ci_job_artifact, :common_security_report) }
     let(:report) { Gitlab::Ci::Reports::Security::Report.new(artifact.file_type, pipeline, 2.weeks.ago) }
     let(:location) { ::Gitlab::Ci::Reports::Security::Locations::DependencyScanning.new(file_path: 'yarn/yarn.lock', package_version: 'v2', package_name: 'saml2') }
+    let(:tracking_data) do
+      {
+        'type' => 'source',
+        'items' => [
+          'fingerprints' => [
+            { 'algorithm' => 'hash', 'value' => 'hash_value' },
+            { 'algorithm' => 'location', 'value' => 'location_value' },
+            { 'algorithm' => 'scope_offset', 'value' => 'scope_offset_value' }
+          ]
+        ]
+      }
+    end
 
     before do
       allow_next_instance_of(described_class) do |parser|
         allow(parser).to receive(:create_location).and_return(location)
+        allow(parser).to receive(:tracking_data).and_return(tracking_data)
       end
-
       artifact.each_blob { |blob| described_class.parse!(blob, report) }
     end
 
@@ -187,5 +199,36 @@ RSpec.describe Gitlab::Ci::Parsers::Security::Common do
         expect(finding_uuids).to match_array(expected_uuids)
       end
     end
+
+    describe 'parsing tracking' do
+      context 'with valid tracking information' do
+        it 'creates fingerprints for each algorithm' do
+          finding = report.findings.first
+          expect(finding.fingerprints.size).to eq(3)
+          expect(finding.fingerprints.map(&:algorithm_type).to_set).to eq(Set['hash', 'location', 'scope_offset'])
+        end
+      end
+
+      context 'with invalid tracking information' do
+        let(:tracking_data) do
+          {
+            'type' => 'source',
+            'items' => [
+              'fingerprints' => [
+                { 'algorithm' => 'hash', 'value' => 'hash_value' },
+                { 'algorithm' => 'location', 'value' => 'location_value' },
+                { 'algorithm' => 'INVALID', 'value' => 'scope_offset_value' }
+              ]
+            ]
+          }
+        end
+
+        it 'ignores invalid algorithm types' do
+          finding = report.findings.first
+          expect(finding.fingerprints.size).to eq(2)
+          expect(finding.fingerprints.map(&:algorithm_type).to_set).to eq(Set['hash', 'location'])
+        end
+      end
+    end
   end
 end

ee/spec/lib/gitlab/ci/reports/security/finding_fingerprint_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::Ci::Reports::Security::FindingFingerprint do
+  subject { described_class.new(params.with_indifferent_access) }
+
+  let(:params) do
+    {
+      algorithm_type: 'hash',
+      fingerprint_value: 'FINGERPRINT'
+    }
+  end
+
+  describe '#initialize' do
+    context 'when a supported algorithm type is given' do
+      it 'allows itself to be created' do
+        expect(subject.algorithm_type).to eq(params[:algorithm_type])
+        expect(subject.fingerprint_value).to eq(params[:fingerprint_value])
+      end
+    end
+  end
+
+  describe '#to_h' do
+    it 'returns a hash representation of the fingerprint' do
+      expect(subject.to_h).to eq(
+        algorithm_type: params[:algorithm_type],
+        fingerprint_sha256: Digest::SHA1.digest(params[:fingerprint_value])
+      )
+    end
+  end
+
+  describe '#valid?' do
+    context 'when supported algorithm_type is given' do
+      it 'is valid' do
+        expect(subject.valid?).to eq(true)
+      end
+    end
+
+    context 'when an unsupported algorithm_type is given' do
+      let(:params) do
+        {
+          algorithm_type: 'INVALID',
+          fingerprint_value: 'FINGERPRINT'
+        }
+      end
+
+      it 'is not valid' do
+        expect(subject.valid?).to eq(false)
+      end
+    end
+  end
+end

ee/spec/services/security/store_report_service_spec.rb

@@ -30,11 +30,11 @@ RSpec.describe Security::StoreReportService, '#execute' do
 
     using RSpec::Parameterized::TableSyntax
 
-    where(:case_name, :trait, :scanners, :identifiers, :findings, :finding_identifiers, :finding_pipelines, :remediations) do
-      'with SAST report'                | :sast                            | 3 | 17 | 33 | 39 | 33 | 0
-      'with exceeding identifiers'      | :with_exceeding_identifiers      | 1 | 20 | 1  | 20 | 1  | 0
-      'with Dependency Scanning report' | :dependency_scanning_remediation | 1 | 3  | 2  | 3  | 2  | 1
-      'with Container Scanning report'  | :container_scanning              | 1 | 8  | 8  | 8  | 8  | 0
+    where(:case_name, :trait, :scanners, :identifiers, :findings, :finding_identifiers, :finding_pipelines, :remediations, :fingerprints) do
+      'with SAST report'                | :sast                            | 3 | 17 | 33 | 39 | 33 | 0 | 2
+      'with exceeding identifiers'      | :with_exceeding_identifiers      | 1 | 20 | 1  | 20 | 1  | 0 | 0
+      'with Dependency Scanning report' | :dependency_scanning_remediation | 1 | 3  | 2  | 3  | 2  | 1 | 0
+      'with Container Scanning report'  | :container_scanning              | 1 | 8  | 8  | 8  | 8  | 0 | 0
     end
 
     with_them do
@@ -65,6 +65,10 @@ RSpec.describe Security::StoreReportService, '#execute' do
       it 'inserts all vulnerabilities' do
         expect { subject }.to change { Vulnerability.count }.by(findings)
       end
+
+      it 'inserts all fingerprints' do
+        expect { subject }.to change { Vulnerabilities::FindingFingerprint.count }.by(fingerprints)
+      end
     end
 
     context 'when report data includes all raw_metadata' do
@@ -116,6 +120,13 @@ RSpec.describe Security::StoreReportService, '#execute' do
     let(:new_build) { create(:ci_build, pipeline: new_pipeline) }
     let(:new_pipeline) { create(:ci_pipeline, project: project) }
     let(:new_report) { new_pipeline.security_reports.get_report(report_type.to_s, artifact) }
+    let(:existing_fingerprint) { create(:vulnerabilities_finding_fingerprint, finding: finding) }
+    let(:unsupported_fingerprint) do
+      create(:vulnerabilities_finding_fingerprint,
+        finding: finding,
+        algorithm_type: ::Vulnerabilities::FindingFingerprint.algorithm_types[:location])
+    end
+
     let(:trait) { :sast }
 
     let!(:finding) do
@@ -195,6 +206,31 @@ RSpec.describe Security::StoreReportService, '#execute' do
       expect(finding.reload).to have_attributes(severity: 'medium', name: 'Probable insecure usage of temp file/directory.')
     end
 
+    it 'updates fingerprints to match new values' do
+      existing_fingerprint
+      unsupported_fingerprint
+
+      expect(finding.fingerprints.count).to eq(2)
+      fingerprint_algs = finding.fingerprints.map(&:algorithm_type).sort
+      expect(fingerprint_algs).to eq(%w[hash location])
+
+      subject
+
+      finding.reload
+      existing_fingerprint.reload
+
+      # check that unsupported algorithm is not deleted
+      expect(finding.fingerprints.count).to eq(3)
+      fingerprint_algs = finding.fingerprints.sort.map(&:algorithm_type)
+      expect(fingerprint_algs).to eq(%w[hash location scope_offset])
+
+      # check that the existing hash fingerprint was updated/reused
+      expect(existing_fingerprint.id).to eq(finding.fingerprints.min.id)
+
+      # check that the unsupported fingerprint was not deleted
+      expect(::Vulnerabilities::FindingFingerprint.exists?(unsupported_fingerprint.id)).to eq(true)
+    end
+
     it 'updates existing vulnerability with new data' do
       subject
 

spec/fixtures/security_reports/master/gl-sast-report.json

@@ -28,7 +28,21 @@
       "file": "python/hardcoded/hardcoded-tmp.py",
       "line": 1,
       "url": "https://docs.openstack.org/bandit/latest/plugins/b108_hardcoded_tmp_directory.html",
-      "tool": "bandit"
+      "tool": "bandit",
+      "tracking": {
+        "type": "source",
+        "items": [
+          {
+            "file": "python/hardcoded/hardcoded-tmp.py",
+            "start_line": 1,
+            "end_line": 1,
+            "fingerprints": [
+              { "algorithm": "hash", "value": "HASHVALUE" },
+              { "algorithm": "scope_offset", "value": "python/hardcoded/hardcoded-tmp.py:ClassA:method_b:2" }
+            ]
+          }
+        ]
+      }
     },
     {
       "category": "sast",