Tutorial B5-2 Breaking DES (Straightforward)

This tutorial has been updated for ChipWhisperer 4.0.0 release. If you are using 3.x.x see the "V3" link in the sidebar.

B5-2: Breaking DES (Straightforward)
Target Architecture	XMEGA
Hardware Crypto	No
Software Release	V3 / V4 / V5

Follow the same procedure as in : Tutorial B5 Breaking AES (Straightforward), but:

1. Flashing the DES firmware to the target device (e.g. chipwhisperer/hardware/victims/firmware/simpleserial-des/simpleserial-des-xmega.hex), instead;
2. Setting an appropriate 'Total Samples' (e.g. 3500) and 'Offset' (e.g. 15500) in the Scope Settings;
3. Setting the 'Key Length (Bytes)', 'Input Length (Bytes)' and 'Output Length (Bytes)' to 8 bytes in the Target Settings;
4. Setting an appropriate 8 bytes Key in the Generic Settings (e.g. 2B 7E 15 16 28 AE D2 A6).

• Or, alternatively, execute the script "setup_cwlite_xmega_des.py" to perform steps 2-4 (you still need to perform step 1 yourself).

In the Analyzer, you'll need to modify the script to call the DES model instead of the AES model. This will mean:

from chipwhisperer.analyzer.attacks.models.DES import DES, SBox_output

And setting:

leak_model = DES(SBox_output)

See the example analyzer script for a complete listing of the required commands.

Note that the attack attemps to recover the first round key, which only has 48bits (8 s-boxes x 6 bits each), while the original key has 56 significative bits (64 if we count the parity bits that are irrelevant). So, if we map the first round key, obtained after the attack, to the original key (you can use the provided DES Key Schedule Tool to do it), there will still be 8 bits missing (256 combinations).

In this example, it matches the original key that was:

Links

Tutorials

See Tutorial Map for important information & suggested order of completion.

Theory

Correlation Power Analysis

Template Attacks

Extending AES-128 Attacks to AES-256

Basic Tutorials

Tutorial B1 Building a SimpleSerial Project

Tutorial B2 Viewing Instruction Power Differences

Tutorial B3-1 Timing Analysis with Power for Password Bypass

Tutorial B5 Breaking AES (Straightforward)

Tutorial B6 Breaking AES (Manual CPA Attack)

Tutorial B7 Profiling Attacks (with HW Assumption)

Tutorial B11 Breaking RSA

Advanced Tutorials

Tutorial A2 Introduction to Glitch Attacks (including Glitch Explorer)

Tutorial A3 VCC Glitch Attacks

Tutorial A5 Breaking AES-256 Bootloader

Tutorial A5-Bonus Breaking AES-256 Bootloader

Tutorial A7 Glitch Buffer Attacks

Tutorial A8 32bit AES

Hardware-Specific Tutorials

Tutorial P1 Stream Mode and Advanced Triggering (CW Pro)

Tutorial CW305-1 Building a Project

Tutorial CW305-2 Breaking AES on FPGA

Tutorial CW305-3 Clock Glitching

Tutorial CW305-4 Voltage Glitching with Crowbars

Archived Tutorials (v4/v3 only)

Tutorial B3-2 Timing Analysis with Power for Attacking TSB

Tutorial B4 Testing Two Partitions of Traces

Tutorial B5-2 Breaking DES (Straightforward)

Tutorial B8 Profiling Attacks (Manual Template Attack)

Tutorial B9 The Preprocessing Modules

Tutorial B10 Using with SASEBO-W CardOS or DPA Contest v4.2

Tutorial A1 Synchronization to Communication Lines

Tutorial A4 SAD Trigger for SCA and Glitch

Tutorial A6 Replication of Ilya Kizhvatov's XMEGA® Attack

Tutorial A9 Bypassing LPC1114 Read Protect