Review unknown code with static analysis php ipc 2018
0 likes172 views
The document outlines a session on static analysis of PHP code, highlighting the challenges in reviewing unknown code and the tools available for effective analysis. It discusses issues like migration differences between PHP versions and various types of automated code reviews, along with examples of code patterns and their prevalence. The session emphasizes best practices, security, performance, and the importance of maintaining clean code through analysis techniques.
![Semantics and definitions
Removes spaces, comments, documentations
Removes delimiters
( ) { } [ ] " ' ` ; :
Good network to link definition with usage](https://image.slidesharecdn.com/reviewunknowncodewithstaticanalysis-phpipc2018-180620160149/85/Review-unknown-code-with-static-analysis-php-ipc-2018-28-320.jpg)
Review unknown code with static analysis php ipc 2018
- 1. REVIEW UNKNOWN CODE WITH STATIC ANALYSIS Berlin, Germany, June 2018
- 2. Agenda Reviewing code Static analysis for PHP A session in which you are the hero
- 3. Review some PHP code We don't know what it does We have never heard about it We don't run it We don't know the authors Can we have an opinion?
- 4. Review the code Reading code is humanly possible : its an art Unit test are not adapted for review Dynamic analysis is not fit for review We need to explore code We can only rely on the current state
- 5. Speaker Damien Seguy Exakat CTO Static analysis for PHP Elephpant retirement home Ich spreche kein Deutsch
- 6. Source code is structured Source code is a structured dataset We need tools to query it This is static analysis
- 8. Appinfo() List PHP features Focus on PHP's specifics
- 9. PHP Features
- 14. Extensions 1 / 2
- 15. Extensions 2 / 2
- 16. Application favorites Many solutions to the same problem Impact on PHP is minimal Generate never-ending discussions Rule : choose one, stick to it
- 19. Automated code review Analyze code Report PHP related problems
- 21. Tactical mistakes in the code PHP classic trap Development left overs Dead code Code modernisation Literal bugs
- 22. Clean code for PHP Best practices Security, performance, clean code in-house, PSR, calisthenics, other inspirations Code mantras, code kata PHP Manual Migration guides
- 24. Exakat : 650 analysis Analysis Freq. Here function __destruct() { throw …} : 0,3 % 0 0.6% 0 function foo($a, $a, $a) {} 2.0% 0 substr($a, 2, 4) == 'abc' 6.9% 0 !!(expression) 8.0% 34 $a ? $b ? $c : $d : $e 11% 2 if (strpos($a, $b)) {} 46% 40 include('file.php') 55% 180 foreach($a as &$b) {} 60% 30
- 25. Which PHP version? List of directives
- 26. Automated code review Semantic read of the code Reports interesting issues Works with AST
- 27. Automated code review PHP 5 / 7 Calisthenics ClearPHP Performance
- 28. Semantics and definitions Removes spaces, comments, documentations Removes delimiters ( ) { } [ ] " ' ` ; : Good network to link definition with usage
- 30. Flow Control Graph <?php $x = source(); if ($x < 10) { $y = $x + 1; $a = 3; $x = corrige($y); } else { $y = $x; } $x = source; if ($x < 10) $y = $x; $y = $x + 1; $x = corrige($y); end $a = 3; start
- 31. Data Dependency Graph <?php $x = source(); if ($x < 10) { $y = $x + 1; $a = 3; $x = corrige($y); } else { $y = $x; } $x = source; if ($x < 10) $y = $x;$y = $x + 1; $x = corrige($y); fin(); Depends onDepends on Depends on notDepends on Depends on $a = 3; Depends on
- 32. Various AST PHP7mar : nikic/php5-ast PHAN : ext/ast (PHP 7 only) Exakat : AST in a graph database SonarQube : Java-build AST PHPstorm : internal IDE AST Reflexion / Better Reflexion
- 33. PHAN PhanTypeMismatchArgument Argument 2 (order) is false but EGroupwareApi Hooks::process() takes array|string defined at Total : 11999 results / 96 types 1679 issues PhanTypeArraySuspiciousNullable Suspicious array access to nullable ?array|null 1256 issues PhanUndeclaredClassMethod Call to method decode from undeclared class Horde_Mime 1247 issues PhanUndeclaredProperty Reference to undeclared property calendar_bo->total PhanTypeInvalidDimOffset Invalid offset "timeformat" of array type array{tz:mixed} 999 issues 668 issues
- 34. PHP 7 helps static analysis Type hint, return type hint, scalar typehint Usage of PHPDOC Consistent behavior of PHP operators Dynamic code is very difficult to analyze
- 35. PHP LINT php -l <fichier.php> Paralell executions jakub-onderka/php-paralell-lint Various versions of PHP : 7.0, 7.1, 7.2, 7.3, 5.6, 5.5
- 36. PHP LINT - 5.5->7.3 Not a single error 615 compiled files PHP 7.2.6 | 10 parallel jobs ............................................................ 60/615 (9 %) ............................................................ 120/615 (19 %) ............................................................ 180/615 (29 %) ............................................................ 240/615 (39 %) ............................................................ 300/615 (48 %) ............................................................ 360/615 (58 %) ............................................................ 420/615 (68 %) ............................................................ 480/615 (78 %) ............................................................ 540/615 (87 %) ............................................................ 600/615 (97 %) ............... 615/615 (100 %) Checked 615 files in 4 seconds No syntax error found
- 37. 0 1.25 2.5 3.75 5 5.2 5.3 5.4 5.5 5.6 7.0 7.1 7.2 0 1 2 3 4 5.2 5.3 5.4 5.5 5.6 7.0 7.1 7.2 0 0.75 1.5 2.25 3 5.2 5.3 5.4 5.5 5.6 7.0 7.1 7.2 0 1.75 3.5 5.25 7 5.2 5.3 5.4 5.5 5.6 7.0 7.1 7.2 5.2 5.3 5.4 5.5 5.6 7.0 7.1 7.2 5.2 5.3 5.4 5.5 5.6 7.0 7.1 7.2 5.2 5.3 5.4 5.5 5.6 7.0 7.1 7.2 5.2 5.3 5.4 5.5 5.6 7.0 7.1 7.2
- 38. What does this app do? Inventories of the application Names for classes, methods, traits, variables, interfaces… List of literal in the code Integers, real, arrays, strings
- 39. Errors messages
- 40. Classes timesheet_hooks 1 timesheet_import_csv 1 timesheet_merge 1 timesheet_tracking 1 timesheet_ui 1 timesheet_wizard_export_csv 1 timesheet_wizard_import_csv 1 uiconfig 1 Customfields 2 Dbmailuser 2 File 2 Files 2 Html 2 Image 2 Link 2 Mail 2 Merge 2 Request 2 Session 2 Template 2 Tracking 2 Vfs 2 Base 3 Cache 3 Storage 3 Univention 3 Ads 4 Exception 4 Sql 4 StreamWrapper 4 Hooks 5 Ldap 5
- 41. Variables $folder 5 $link 5 $n 5 $resource 5 $script 5 $val 5 $vcard 5 $_headerobject 6 $appdata 6 $contact 6 $etemplate 6 $field 6 $name 6 $recurrence 6 $replacements 6 $account 7 $config 7 $list 7 $options 7 $v 7 $col 8 $item 8 $alarm 9 $event 9 $settings 9 $status 10 $id 12 $prop 13 $label 16 $data 19 $row 21 $value 21 9439 variables Also : 958 used-once variables
- 42. List of PHP analyzers Exakat Phan Phploc PHPmetrics https://github.com/exakat/ php-static-analysis-tools
- 43. Medium application Internal framework Low level of issues Tend to use old PHP features Backward compatibilities Deal with school : contacts, identity