Software security starts at the source — your code. When your code isn’t secure, a simple coding error could lead to a catastrophic attack. But ensuring secure code can be tricky, particularly in C. And especially if you’re developing embedded software for an automobile, airplane, or medical device. Learn the secret to secure embedded systems. You’ll: -Get an example of a security vulnerability. -Compare four ways to secure embedded systems. -Learn how MISRA C rules ensure secure code.

1. How to Secure
Embedded Systems
With MISRA C Rules
Richard Bellairs

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Presenter
Richard Bellairs
Product Marketing Manager
Richard has 20+ years of experience across a wide range
of industries. He held electronics and software engineering
positions in the manufacturing, defense, and test and
measurement industries in the nineties and early noughties
before moving to product management and product
marketing. He now champions Perforce’s market-leading
code quality management solution.

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1
What is ‘Secure Code’?
2
How to Ensure
Secure Code in C
3
Applying MISRA Security
Rules to Your Code
Here’s What We’ll Cover Today

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90%
of reported security incidents result
from exploits against defects in the
design or code of software.
Coding Errors Compromise Security

5. “Devil’s Ivy” gives hackers access to
millions of connected devices.

6. In July 2015, Fiat Chrysler recalled 1.4 million
vehicles at risk of wireless hack.

7. In May 2018, it was reported that VPNFilter malware had
infected at least 500,000 routers and NAS devices.

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https://dhavalkapil.com/blogs/
Buffer-Overflow-Exploit/
void func(int a, int b)
{
int c;
int d;
// some code
}
void main()
{
func(1, 2);
// next instruction
}
char buff[10];
buff[10] = 'a';
The stack while in func():
Example of a Security Vulnerability: Buffer
Overflow in C
2
1
<return address>
<%ebp of main()>
<space for ‘c’>
<space for ‘d’>
<-- %ebp
<-- %esp

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https://dhavalkapil.com/blogs/Buffer-Overflow-Exploit/
#include <stdio.h>
void secretFunction()
{
printf("Congratulations!n");
printf("You have entered in the secret
function!n");
}
void echo()
{
char buffer[20];
printf("Enter some text:n");
scanf("%s", buffer);
printf("You entered: %sn", buffer);
}
int main()
{
echo();
return 0;
}
Example of a Security Vulnerability:
Buffer Overflow in C

10. Preventing Security Vulnerabilities is Critical

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ISO/IEC TS 17961:2013
4 Ways to Ensure Secure Code in C

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What is MISRA?
ISO 17961
MISRA C:2012
MISRA C:2012
Amendment 1

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• MISRA C Rule 18.1
• “A pointer resulting from arithmetic on
a pointer operand shall address an
element of the same array as that
pointer operand.”
• CERT ARR30-C
• “Do not form or use out-of-bounds
pointers or array subscripts.”
• CWE-119
• Improper Restriction of Operations
within the Bounds of a Memory Buffer
Example of a MISRA C Security Rule

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Comparing MISRA C and Other Standards
MISRA C Coverage of C Secure MISRA C Coverage of CERT C
One or more MISRA Rules
One or more MISRA Directives
One or more MISRA Rules
One or more MISRA Directives
Out of Scope
Not Covered

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• Coding defects lead to catastrophic
security breaches and fatal safety flaws.
• Static analyzers scan source code to:
• Detect bugs.
• Ensure compliance with best
practice coding standards, like MISRA.
• So, you’ll produce safe, secure, reliable
software at lower cost.
Static Code Analyzers Apply MISRA Rules

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Helix QAC
Server
Helix QAC’s MISRA C compliance module covers 100% of the rules, with the deepest coverage.
Apply MISRA Security Rules to Your Code

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Established for over 30 years
Combines state of the art methods
Scan large-scale projects
Independently certified
Integrate with existing tools and CI process
Report code quality trends and code metrics
Gold standard for critical applications
Most precise analysis of C and C++ code
Project proven with millions of lines of code
Compliant with international standards
Friction-free deployment
Manage and improve code quality
Why Helix QAC for C and C++?

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The average cost of fixing defects depending on the time they have been made and
detected (the data for the table is taken from the book "Code Complete" by S. McConnell).
Time Detected
Time
Introduced
Requirements Architecture Construction System Test Post-Release
Requirements 1 3 5 - 10 10 10 - 100
Architecture - 1 10 15 25 - 100
Construction - - 1 10 10 - 25
Static code
analysis
Safe, Secure, and Reliable Software
Can Be Achieved at Lower Costs

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We focus on
solutions for large
scale product
development that
increases
productivity.
We maintain key
integrations with
top tools for
seamless process
automation.
• Align product with
business requirements
• Accelerate innovation
• Faster time to market
DevSecOps at Scale
• Improve productivity
and efficiency
• Better quality

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Check your
code.
Apply your
coding
standard.
Meet safety
and security
standards.
Improve
code quality.
Reduce time
and cost.
Continuous Code Quality

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Recap
1
What is ‘Secure Code’?
2
How to Ensure
Secure Code in C
3
Applying MISRA Security
Rules to Your Code

22. Questions?

23. Contact us to schedule a demo!
info@perforce.com

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