HemSök efter kurserSecure Coding in C and C++

Secure Coding in C and C++

Your application written in C or C++ works as intended, so you are done, right? But did you consider feeding in incorrect values? 16Gbs of data? A null? An apostrophe? Negative numbers, or specifically -232? Because that’s what the bad guys will do – and the list is far from complete.

Handling security needs a healthy level of paranoia, and this is what this course provides: a strong emotional engagement by lots of hand on labs and stories from real life, all to substantially improve code hygiene. Mistakes, consequences and best practices are our blood, sweat and tears.

All this is put in the context of C and C++, and extended by core programming issues, discussing security pitfalls of code written in these languages.

So that you are prepared for the forces of the dark side.
So that nothing unexpected happens.

Nothing

 

Delivered onsite for three days, 9-17.00
Delivered online for five days, Monday - Friday 9-13.00


Utbildningsformer
Remote

Längd
3 dagar

Pris
29400 kr

Audience

C/C++ developers.

What you'll have learned

  • Getting familiar with essential cyber security concepts
  • Identify vulnerabilities and their consequences
  • Learn the security best practices in C and C++
  • Input validation approaches and principles

Preparedness

General C/C++ development.

Conent of Secure Coding in C and C++

Day 1

Cyber security basics

  • What is security?
  • Threat and risk
  • Cyber security threat types
  • Consequences of insecure software
     - Constraints and the market
     - The dark side

Memory management vulnerabilities

  • Assembly basics and calling conventions
     - x64 assembly essentials
     - Registers and addressing
     - Most common instructions
     - Calling conventions on x64
        - Calling convention – what it is all about
        - The stack frame
        - Stacked function calls

  • Buffer overflow
     - Memory management and security
     - Vulnerabilities in the real world
     - Buffer security issues
     - Buffer overflow on the stack
        - Buffer overflow on the stack – stack smashing
        - Exploitation – Hijacking the control flow
        - Lab – Buffer overflow 101, code reuse
        - Exploitation – Arbitrary code execution
        - Injecting shellcode
        - Lab – Code injection, exploitation with shellcode
     - Buffer overflow on the heap
        - Unsafe unlinking
        - Case study – Heartbleed
      - Pointer manipulation
        - Modification of jump tables
        - Overwriting function pointers

  • Best practices and some typical mistakes
     - Unsafe functions
     - Dealing with unsafe functions
     - Lab – Fixing buffer overflow
     - What’s the problem with asctime()?
     - Lab – The problem with asctime()
     - Using std::string in C++
     - Unterminated strings
     - readlink() and string termination
     - Manipulating C-style strings in C++
     - Malicious string termination
     - Lab – String termination confusion
     - String length calculation mistakes
     - Off-by-one errors
     - Allocating nothing

Day 2

Memory management hardening

  • Securing the toolchain
     - Securing the toolchain in C and C++
     - Compiler warnings and security
     - Using FORTIFY_SOURCE
     - Lab – Effects of FORTIFY
     - AddressSanitizer (ASan)
        - Using AddressSanitizer (ASan)
        - ASan changes to the prologue
        - ASan changes to memory read/write operations
        - ASan changes to the epilogue
        - Lab – Using AddressSanitizer
     - Stack smashing protection
        - Detecting BoF with a stack canary
        - Argument cloning
        - Stack smashing protection on various platforms
        - SSP changes to the prologue and epilogue
        - Lab – Effects of stack smashing protection

  • Runtime protections
     - Runtime instrumentation
     - Address Space Layout Randomization (ASLR)
        - ASLR on various platforms
        - Lab – Effects of ASLR
        - Circumventing ASLR – NOP sleds
        - Circumventing ASLR – memory leakage
     - Non-executable memory areas
        - The NX bit
        - Write XOR Execute (W^X)
        - NX on various platforms
        - Lab – Effects of NX
        - NX circumvention – Code reuse attacks
           - Return-to-libc / arc injection
        - Return Oriented Programming (ROP)
           - Protection against ROP

Common software security weaknesses

  • Security features
     - Authentication
        - Authentication basics
        - Multi-factor authentication
        - Authentication weaknesses
        - Case study – PayPal 2FA bypass
  • Password management
     - Inbound password management
        - Storing account passwords
        - Password in transit
        - Lab – Is just hashing passwords enough?
        - Dictionary attacks and brute forcing
        - Salting
        - Adaptive hash functions for password storage
        - Password policy
           - NIST authenticator requirements for memorized secrets
     - Case study – The Ashley Madison data breach
        - The dictionary attack
        - The ultimate crack
        - Exploitation and the lessons learned
     - Password database migration

Code quality

  • Code quality and security
  • Data handling
     - Type mismatch
     - Lab – Type mismatch
     - Initialization and cleanup
        - Constructors and destructors
        - Initialization of static objects
        - Lab – Initialization cycles
        - Array disposal in C++
        - Lab – Mixing delete and delete[]
  • Memory and pointers
     - Memory and pointer issues
     - Pointer handling pitfalls
     - Pointer usage in C and C++
        - Use after free
        - Lab – Use after free
        - Lab – Runtime instrumentation
        - Double free
        - Memory leak
        - Smart pointers and RAII
        - Smart pointer challenges

Day 3

Common software security weaknesses

  • Input validation
     - Input validation principles
        - Blacklists and whitelists
        - Data validation techniques
        - What to validate – the attack surface
        - Where to validate – defense in depth
        - When to validate – validation vs transformations
        - Validation with regex
        - Regular expression denial of service (ReDoS)
        - Lab – ReDoS in C++
        - Dealing with ReDoS
     - Injection
        - Injection principles
        - Injection attacks
        - Code injection
           - OS command injection
              - Lab – Command injection
              - OS command injection best practices
              - Avoiding command injection with the right APIs
              - Lab – Command injection best practices
              - Case study – Shellshock
              - Lab – Shellshock
     - Process control – library injection
        - Library hijacking
        - Lab – Library hijacking
     - Integer handling problems
        - Representing signed numbers
        - Integer visualization
        - Integer promotion
        - Integer overflow
        - Lab – Integer overflow
        - Signed / unsigned confusion
        - Case study – The Stockholm Stock Exchange
        - Lab – Signed / unsigned confusion
        - Integer truncation
        - Lab – Integer truncation
        - Case study – WannaCry
        - Best practices
           - Upcasting
           - Precondition testing
           - Postcondition testing
           - Using big integer libraries
           - Best practices in C
           - UBSan changes to arithmetics
          - Lab – Handling integer overflow on the toolchain level in C and C++
     - Files and streams
        - Path traversal
        - Lab – Path traversal
        - Path traversal-related examples
        - Virtual resources
        - Path traversal best practices
        - Lab – Path canonicalization
     - Format string issues
        - The problem with printf()
        - Lab – Exploiting format string

Wrap up

  • Secure coding principles
     - Principles of robust programming by Matt Bishop
     - Secure design principles of Saltzer and Schröder

And now what?

  • Software security sources and further reading
  • C and C++ resources