secure programming lecture 1: introduction

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Secure Programming Lecture 1: Introduction David Aspinall, Informatics @ Edinburgh 17th January 2019

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Page 1: Secure Programming Lecture 1: Introduction

Secure Programming Lecture 1:Introduction

David Aspinall, Informatics @ Edinburgh

17th January 2019

Page 2: Secure Programming Lecture 1: Introduction

Orientation

É This course is Secure Programming.

É More accurately: it is about Software Security.É Aimed at Informatics MSc and 4th/5th year

studentsÉ Primarily: those anticipating a career in software

É programming: architects, developers, testers, . . .É security: pentesters, malware/reverse engineersÉ researchers: verification, compilers, languages, . . .

É It is taught by David Aspinall.

Web home:http://www.inf.ed.ac.uk/teaching/courses/sp

Page 3: Secure Programming Lecture 1: Introduction

Outline

Recent motivations

Course syllabus

Software security overview

Practicalities

Structure of course

Summary

Page 4: Secure Programming Lecture 1: Introduction

Ubiquitous software is broken (2014)

Page 5: Secure Programming Lecture 1: Introduction

Ubiquitous hardware is flawed (2018)

Page 6: Secure Programming Lecture 1: Introduction

Attacks can cause physical damage (2014)

Page 7: Secure Programming Lecture 1: Introduction

Nobody can keep online records safe (2015)

Page 8: Secure Programming Lecture 1: Introduction

Known good practice ignored (2015)

Page 9: Secure Programming Lecture 1: Introduction

IoT easily raises a DDoS botnet army (2016)

Page 10: Secure Programming Lecture 1: Introduction

Why does this happen?Ostensibly, many security failures are due tosoftware vulnerabilities. Are they inevitable?

Many surrounding questions. Can we:

É find vulnerabilities (before attacks)?É detect exploits in-the-wild?É repair vulnerabilities (routinely/automatically)?É program better to avoid vulnerabilities?É measure risk associated with software?É design or verify to prevent them?É develop new technology to help the above?

Questions beyond the technical, too. Can we:

É insure against cyber incidents?É regulate for better security?

Page 11: Secure Programming Lecture 1: Introduction

Outline

Recent motivations

Course syllabus

Software security overview

Practicalities

Structure of course

Summary

Page 12: Secure Programming Lecture 1: Introduction

What is this course about?Building software that’s more secure

É finding flaws in existing softwareÉ avoiding flaws in new software (design and code)É techniques, tools and understanding to do this

The infrastructure around secure software:

É language, libraries, run-time; other programsÉ data storage, distribution, protocols and APIsÉ development and deployment methods

And first of all, setting policies for security

É what should be protectedÉ who/what is trustedÉ risk assessment: cost of defences.

Page 13: Secure Programming Lecture 1: Introduction

Target audience

É Aimed at MSc, 4th/5th year UGsÉ Have passed Computer Security or similar

É Basic notions, crypto, protocols

É Programming practiceÉ must be confident in programmingÉ necessarily will use a range of languagesÉ . . . including assember, C, JavaÉ but don’t have be “master hacker”É grounded in software engineering

É Programming theoryÉ interest in PL concepts and designÉ knowledge of compilers usefulÉ also software engineering, esp, testingÉ theory courses helpful, semantics

Page 14: Secure Programming Lecture 1: Introduction

Why should you take this course?

Want to work in the cyber security industry?

É security appraisal, system and code reviewingÉ pen-testing, ethical hackingÉ malware analysis, reverse engineeringÉ operations and response (SOCs)É cyber defence, attack, espionageÉ innovation: found a cyber start-up

Want to work in security research?

É academic (conceptual advances, fixing, breaking)É commercial (breaking, fixing, defending)

(Hopefully): you think it’s fun and interesting!

Page 15: Secure Programming Lecture 1: Introduction

Why should you not take this course?

É None of the previous points apply.É You don’t have the right background (see next slide)

Or perhaps, you don’t want to risk a relatively newand changing course. The course is revised to followlatest ideas and developments. Frank and constructivefeedback is very welcome.

Page 16: Secure Programming Lecture 1: Introduction

Expected background

Please see Guide to Background Needed on coursehomepage.

1. Security properties: C, I, A, non-repudiation, privacy

2. Attacks against each of these3. Defences: Au x 2, access control, crypto, networks4. Coding skills and problem solving5. Practicals: command line Linux

Page 17: Secure Programming Lecture 1: Introduction

Expected background

Please see Guide to Background Needed on coursehomepage.

1. Security properties: C, I, A, non-repudiation, privacy2. Attacks against each of these

3. Defences: Au x 2, access control, crypto, networks4. Coding skills and problem solving5. Practicals: command line Linux

Page 18: Secure Programming Lecture 1: Introduction

Expected background

Please see Guide to Background Needed on coursehomepage.

1. Security properties: C, I, A, non-repudiation, privacy2. Attacks against each of these3. Defences: Au x 2, access control, crypto, networks

4. Coding skills and problem solving5. Practicals: command line Linux

Page 19: Secure Programming Lecture 1: Introduction

Expected background

Please see Guide to Background Needed on coursehomepage.

1. Security properties: C, I, A, non-repudiation, privacy2. Attacks against each of these3. Defences: Au x 2, access control, crypto, networks4. Coding skills and problem solving

5. Practicals: command line Linux

Page 20: Secure Programming Lecture 1: Introduction

Expected background

Please see Guide to Background Needed on coursehomepage.

1. Security properties: C, I, A, non-repudiation, privacy2. Attacks against each of these3. Defences: Au x 2, access control, crypto, networks4. Coding skills and problem solving5. Practicals: command line Linux

Page 21: Secure Programming Lecture 1: Introduction

Learning outcomes

1. Know how to respond to (software) security alerts.2. Identify possible security programming errors when

conducting code reviews.3. Be able to define a methodology for security testing

and use appropriate tools in its implementation.4. Apply new security-enhanced programming models

and tools which help ensure security goals, e.g., withaccess control, information flow tracking, protocolimplementation, or atomicity enforcement.

Page 22: Secure Programming Lecture 1: Introduction

Outline

Recent motivations

Course syllabus

Software security overview

Practicalities

Structure of course

Summary

Page 23: Secure Programming Lecture 1: Introduction

Safety versus security

Safety is concerned with ensuring bad things don’thappen accidently. For example, aeroplanes don’t fallout of the sky because maintenance checks areforgotten.

Security is concerned with with ensuring that badthings don’t happen because of malicious actions byothers. For example, terrorists cannot drive bombs intoairport departure halls.

The distinction is sometimes blurred, and the twointeract in intriguing ways. (Q. why?)

Page 24: Secure Programming Lecture 1: Introduction

The challenge of software security

Software artefacts are among the most complex built.

É Design flaws are likely

É Bugs seem inevitable

Flaws and bugs lead to vulnerabilities which areexploited by attackers.

Often to learn secrets, obtain money. But many otherreasons: a security risk assessment for a system shouldconsider different attackers and their motives.

Page 25: Secure Programming Lecture 1: Introduction

The challenge of software security

Software artefacts are among the most complex built.

É Design flaws are likelyÉ Bugs seem inevitable

Flaws and bugs lead to vulnerabilities which areexploited by attackers.

Often to learn secrets, obtain money. But many otherreasons: a security risk assessment for a system shouldconsider different attackers and their motives.

Page 26: Secure Programming Lecture 1: Introduction

The challenge of software security

Software artefacts are among the most complex built.

É Design flaws are likelyÉ Bugs seem inevitable

Flaws and bugs lead to vulnerabilities which areexploited by attackers.

Often to learn secrets, obtain money. But many otherreasons: a security risk assessment for a system shouldconsider different attackers and their motives.

Page 27: Secure Programming Lecture 1: Introduction

The challenge of software security

Software artefacts are among the most complex built.

É Design flaws are likelyÉ Bugs seem inevitable

Flaws and bugs lead to vulnerabilities which areexploited by attackers.

Often to learn secrets, obtain money. But many otherreasons: a security risk assessment for a system shouldconsider different attackers and their motives.

Page 28: Secure Programming Lecture 1: Introduction

Cost estimates are difficult

Page 29: Secure Programming Lecture 1: Introduction

But it’s agreed they’re increasing. . .

Page 30: Secure Programming Lecture 1: Introduction

Cyber warfare is real

Page 31: Secure Programming Lecture 1: Introduction

Privacy is being eroded

Page 32: Secure Programming Lecture 1: Introduction

But maybe there is hope. . .

Page 33: Secure Programming Lecture 1: Introduction

Why isn’t software security better?

Page 34: Secure Programming Lecture 1: Introduction

Why (else) isn’t software security better?

É Asymmetry: attackers have the advantageÉ just need to find one viable attack routeÉ defenders have to anticipate all

É Attackers focus on weakest links:É since 1990s, network defences vastly improvedÉ rise of insider threats

É Current penetrate-and-patch approach is brokenÉ understandable by managers (“show me the

problem!”)É but no substitute for secure design

Page 35: Secure Programming Lecture 1: Introduction

What’s the outlook?

New frontiers:

É PCs in decline, but connected devices increasingÉ Mobile new target point (convergence, mobility)É Internet of Things: repeating same mistakes!É Cloud: XaaS, storageÉ Cyber resilience: speedy, automatic recoveryÉ Data sharing and its limits: privacy

Emerging new solutions:

É Build Security In, Secure By DesignÉ Defensive technologies continuing to evolveÉ New cryptographic, verification techniquesÉ Old ideas re-appear: MLS, containment, isolationÉ Updates: automatic, pushed patching

Page 36: Secure Programming Lecture 1: Introduction

Outline

Recent motivations

Course syllabus

Software security overview

Practicalities

Structure of course

Summary

Page 37: Secure Programming Lecture 1: Introduction

Delivery and assessment

We will have

É 16 lectures covering core course topics

É 5 lab sessionsÉ 1 coursework contributing 30% of final markÉ 1 written exam contributing 70% of final mark

Lecture slides will be made available in several formats.

They have numerous embedded links to useful resources(the links are more noticeable in the online versions).

Lecture recordings will be available, systemspermitting. These are intended as a backup.

Page 38: Secure Programming Lecture 1: Introduction

Delivery and assessment

We will have

É 16 lectures covering core course topicsÉ 5 lab sessions

É 1 coursework contributing 30% of final markÉ 1 written exam contributing 70% of final mark

Lecture slides will be made available in several formats.

They have numerous embedded links to useful resources(the links are more noticeable in the online versions).

Lecture recordings will be available, systemspermitting. These are intended as a backup.

Page 39: Secure Programming Lecture 1: Introduction

Delivery and assessment

We will have

É 16 lectures covering core course topicsÉ 5 lab sessionsÉ 1 coursework contributing 30% of final mark

É 1 written exam contributing 70% of final mark

Lecture slides will be made available in several formats.

They have numerous embedded links to useful resources(the links are more noticeable in the online versions).

Lecture recordings will be available, systemspermitting. These are intended as a backup.

Page 40: Secure Programming Lecture 1: Introduction

Delivery and assessment

We will have

É 16 lectures covering core course topicsÉ 5 lab sessionsÉ 1 coursework contributing 30% of final markÉ 1 written exam contributing 70% of final mark

Lecture slides will be made available in several formats.

They have numerous embedded links to useful resources(the links are more noticeable in the online versions).

Lecture recordings will be available, systemspermitting. These are intended as a backup.

Page 41: Secure Programming Lecture 1: Introduction

Lab sessions

Five 2hr lab sessions (see home page):

É Week 3: Tues 29th Jan 9am-11amÉ Weeks 5,7,9,10: Weds 2pm-4pm

Each session will examine software vulnerabilities: whythey exist, how they can be discovered, exploited, andrepaired.

Labs may start with a short guided introduction.

Working together is encouraged. We want to fostera supportive learning environment. Students who haveprior knowledge or expertise are especially welcome.

Page 42: Secure Programming Lecture 1: Introduction

Formative feedback during Labs

One reason to introduce labs in this course is to allow usto give face-to-face discussion and feedback on yourlearning.

Lab sessions will be run by me together with the courseTA, Arthur Chan.

Page 43: Secure Programming Lecture 1: Introduction

Coursework

The coursework will be an assignment following a similarpattern to the lab exercises: discover, exploit thenrepair.

1. as usual: your work should be your own2. no publication, please do not publish solutions

even after the deadline

(at least two reasons for last point).

The coursework deadline is scheduled for Week 8.

Page 44: Secure Programming Lecture 1: Introduction

An ethical point (reminder)

Nothing in this course is intended as incitementto crack into running systems!

É Breaking into systems to “demonstrate” securityproblems at best causes a headache to overworkedsysadmins, at worst compromises systems for manyusers and could lead to prosecution

É If you spot a security hole in a running system,don’t exploit it, instead contact the relevantadministrators or developers confidentially.

É To experiment with security holes, play with yourown machine, or better, your own privatenetwork of machines.

Page 45: Secure Programming Lecture 1: Introduction

Communications

É Fast moving, evolving course:É honest, constructive feedback is very welcome

É As with any course, I welcomeÉ questions after lecturesÉ questions by email

Shall we have a course-wide online facility? Open toclass opinion:

1. University forum (private in UoE)2. University VLE tool (Learn)3. Piazza for questions, discussion (signup)4. None, but FAQs sent to class list sp-students by

email

Page 46: Secure Programming Lecture 1: Introduction

Exam

Will follow the common format:

É Choose 2 questions to answer from 3É Two hours allowed

Towards the end of the course I will provide:

É a list of topics and concepts that may be examinedÉ a hint about the format of the questions

There is some guidance on the web along with a samplequestion.

Page 47: Secure Programming Lecture 1: Introduction

Outline

Recent motivations

Course syllabus

Software security overview

Practicalities

Structure of course

Summary

Page 48: Secure Programming Lecture 1: Introduction

Dimensions: practice and theoryPractice

É Programming securely, identifying security issuesÉ Mistakes in language, APIs, crypto, comms. . .É Ultimately: detailed, highly specific knowledge

Theory

É Understand reasons for failure, ways to mitigateÉ Understand advanced techniques, automated toolsÉ In general: transferable concepts and methods.

This is not really a “vocational” course. I hope it will giveyou the foundation to allow you to rapidly developdetailed specific knowledge needed later. There are anumber of certification schemes for building practicalknowledge.

Page 49: Secure Programming Lecture 1: Introduction

Overview of topics

General organisation:

1. Threats2. Vulnerabilities3. Defences4. Processes5. Emerging Methods

We’ll look at details under each of these headings (invarious orders).

Page 50: Secure Programming Lecture 1: Introduction

1. Threats

É What attackers want, can doÉ Types of bad code: malware, spyware, PUPsÉ How bad code gets inÉ Classification of vulnerabilities and weaknesses,

CVE/CWEs

Page 51: Secure Programming Lecture 1: Introduction

2. Vulnerabilities

É OverflowsÉ InjectionsÉ Information leaksÉ Race conditionsÉ Side channels and covert channels

Page 52: Secure Programming Lecture 1: Introduction

3. Defences

É Protection mechanisms: validation, diversification,monitoring

É Trade-offs in adding protection mechanismsÉ Provision for recovery

Page 53: Secure Programming Lecture 1: Introduction

4. Processes

É Secure design principlesÉ Testing and reviewing to find vulnerabilitiesÉ Assessing/measuring security of code

Page 54: Secure Programming Lecture 1: Introduction

5. Emerging methods

É Methods and tools to find problemsÉ Detecting buggy patterns automaticallyÉ Building security in, methodology and technology

Page 55: Secure Programming Lecture 1: Introduction

Outline

Recent motivations

Course syllabus

Software security overview

Practicalities

Structure of course

Summary

Page 56: Secure Programming Lecture 1: Introduction

Review questions

Safety versus Security

É Explain the difference between these two, and whyensuring security may be harder.

Security flaws and their impact on society.

É Explain some recent secure programming flaws thatmade the news and explain what the underlyingproblems were.

É Discuss the fundamental reasons that softwaresecurity fails and the wider questions around cybersecurity.

Page 57: Secure Programming Lecture 1: Introduction

References and reading

The slides contain links which you can click on to findreferenced or connected material.

References and reading will also be given for eachlecture in a separate web page for that lecture. For thislecture, see here.

There is no single recommended course textbook,although a few books will be mentioned. See the pageabove for pointers.