Cryptography Stack Exchange
Cryptography Stack Exchange

Questions tagged [embedded]

An embedded system is a computer system with a dedicated function within a larger mechanical or electrical system, often with real-time computing constraints.

An embedded system is a computer system with a dedicated function within a larger mechanical or electrical system, often with real-time computing constraints.

Modern embedded systems are often based on microcontrollers that are dedicated to handle a particular task; for example: encryption and decryption using a specific algorithm (like AES).

The reason to use embedded systems is that design engineers can optimize the particular task(s) handled by the embedded systems. Another positive characteristic of embedded systems is that they allow reduction of size and cost of products, and that they allow increasing the reliability and performance of the embedded system… independently from the main product the embedded system is part of. Simpler said: embedded systems allow mass-production, benefiting from economies of scale.

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Key derivation on Arduino

The ATmega2560 is slow - it's a single core, 16MHz 8-bit AVR. Despite that, I need to use some encryption on it, and since it is limited to a few blocks, AES-256 can be used. However, the key derivation is a problem. A computer can easily do a…
Dash
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Lightweight cipher using only 8-bit operations

What is the most efficient (in cycles per byte) cryptographically secure symmetric cipher to implement using only 8-bit operations? Algorithms like TEA are great for embedded devices, but it is optimized for 32-bit operations. I am not looking for…
forest
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Replay attack prevention in connectionless UDP encrypted communication

What are the options for replay attack prevention when two parties exchange UDP messages. No connection or session is estabilished. Communicating parties have pre shared key that is used for encryption (aes-256) and authentication…
PanJanek
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Tiny Firmware Authentication

I am developing a product based on the NXP LPC11C24 microcontroller. It will communicate with PC software to perform its work. I am attempting to build a secure firmware update functionality. The PC program will download firmware images from us and…
user42679
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Least-weak way to authenticate using only AES ECB/CBC

I have an embedded application that needs to occasionally get secure updates from a server. The only crypto library I have available for the chip is an AES-256 cipher (ECB and CBC, encrypt/decrypt). Is there any worthwhile way to authenticate the…
Chriszuma
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Is there a secure source of entropy on a typical microcontroller?

On a device that does not have a hardware RNG, what is the best source for entropy? Some options and pitfalls floating around: Use the ADC to read something analog: can become deterministic if there is access to power supply or some ADCs are just…
MandoMando
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secure embedded/microcontroller crypto using AES-ctr with hmac-sha2

The embedded device is a low-power 8-bit microcontroller (memory usage is constrained to about 10kb code, 1kb ram). As the device is battery-powered and manual service should be minimal, more powerful processors are not an option. Throughput is very…
rufensuw8
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BN-Curves for 256-bit symmetric security

I'm just studying the purpose of BN-Curves and I am interested in a setting for a 256-Bit security. So could you tell or link me to any information about this? are BN-Curves efficient for this security issue? which embedding degree is…
Shalec
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Signing dynamic data on an embedded system

I have built a GPS based on the AVR microcontroller. The GPS is used to log flight data for competitions. The log file is updated 10 times per second. What I'd like to do is to associate a signature with this file so that anyone can confirm that the…
Michael Cooper
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Fast PKI for embedded device

We are creating a device with a small microcontroller (20 MHz CPU 16 KiB RAM). We need some way to securely send signed files to device (only signature, no encryption necessary). An external company has come up with an elliptic curve solution but it…
Toni Homedes i Saun
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Is my id obfuscation algorithm secure?

I'm designing an id obfuscation system. My system includes: Embedded chips, each chip has a unique 32-bit address (id). Server Insecure low-bandwidth unstable one-way channels from the chips to the server. The chips send messages to the server…
Ozo
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Most simple transport encryption for link-constrained environments

What is the most simple, but yet well-known "protocol" to protect a unidirectional channel over air? Requirements The protocol should provide common properties like privacy, integrity and replay protection. Forward secrecy is not really necessary in…
K. Biermann
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Authenticated encryption scheme for one-way radio telemetry

I'm designing an authenticated encryption scheme for a noninteractive one-way radio telemetry system. A number of devices in the field send back telemetry to a base station periodically, but no communications are sent from the base station to the…
Polynomial
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Does still make sense to use SHA1?

I'm working with Arduino and hash-based signatures which are signature schemes that use only hash functions. Due to the constraints of an Arduino I was thinking about using SHA1 as the underlying function of my hash-based signature. But I'm not sure…
Jéssica Carneiro
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Storing a Secure Boot image with AES-GCM instead of AES + RSA signature

In Secure Boot (here defined as data is encrypted and authenticated), we can encrypt the data with AES-128 and authenticate it with a RSA signature, computed over the data's hash, afterwards. On boot, the device first calculates the hash of the…
Exac
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