Feasibility of Security in Micro-Controllers
- 1. Feasibility of Security in Micro-Controllers Aaron Ardiri! ! ! ! ! ! ! ! Chief Technology Officer - Evothings AB Internet of Things Day, Oslo! ! ! ! ! ! ! ! ! ! ! ! ! 6th November, 2014
- 2. Introduction Evothings is a mobile application enabler for the Internet of Things (IoT) industry, helping developers and technology players that have the need to create mobile applications interfacing with IoT technologies.! ! * come visit us at our booth for a demonstration of our mobile app development suite
- 3. Overview IoT Security! ✤ why is it such a hot topic?! ✤ why has it become an issue in the first place?! ✤ what is the feasibility on the Arduino platform! ✤ what is happening in the IoT developer ecosystem?! ✤ food for thought: are we approaching it correctly?
- 4. IoT Security why is it such a hot topic?
- 5. Hewlett Packard Report HP’s Fortify division recently tested a selection of IoT solutions currently available on the market by popular manufacturers including TVs, webcams, thermostats, power outlets, door locks and home control hubs.! ✤ 250 vulnerabilities found! ✤ 76% of devices used unencrypted network resources! ✤ 80% failed to use strong passwords, many unchanged! ✤ 60% failed to protect firmware downloads/integrity
- 6. Sweden - National Security HOT OF THE PRESS ! ! ! ! ! 3rd November 2014! http://www.dn.se/nyheter/sverige/it-expert-bristerna-ett-hot-mot-rikets-sakerhet/! It was revealed a number of important public properties in Sweden including but not limited to Police Stations, Transit Stations, Data Centers and Space Center in Kiruna are completely open on the Internet and hackable - control of alarms, doors, heating, other sensitive systems! ✤ sites are password protected but have weak security
- 7. IoT Security why has it become such an issue?
- 8. Gartner Hype Cycle Special Report http://www.gartner.com/newsroom/id/2819918 Internet of Things
- 9. Explosion of micro-controllers postscapes.com/internet-of-things-hardware
- 10. Products - what is happening ✤ companies making “land grab” in IoT space! ✤ focus is product-to-market, not deliver quality! ✤ a number of products are based on prototypes! ✤ failure to provide OTA and update mechanisms! ✤ SSL/TLS - implementations! ✤ many micro-controllers have limited CPU / RAM! ✤ existing libraries are not optimised for embedded
- 12. 0-day exploits (security) in 2014 Heartbleed! serious vulnerability in the popular OpenSSL cryptographic software library. ! ShellShock! aka: Bashdoor group of bugs in the popular Bourne Again Shell (Bash).! POODLE! serious vulnerability in the popular OpenSSL cryptographic software library.
- 13. Operating Systems ✤ What are the options for IoT product manufacturers? BareBones OS or
- 14. Security is not only encryption A common mis-conception; it is more than Encryption Integrity Authentication Security Non-Repudiation Confidentiality http://www.securerf.com/security-is-not-encrypting-data/
- 15. IoT Security what is the feasibility on Arduino?
- 16. Public Key Cryptography #1 provide your public key to sender #2 sender uses your public key to encrypt message your public key message cyphertext #3 sender provides cyphertext to you #4 use your private key to decrypt cyphertext cyphertext your private key cyphertext message your public key
- 17. RSA: Basic Overview ✤ encryption! c != me mod n! ✤ decryption! ALGORITHM KEY! ! m ! = original message! c! = cyphertext! ! e! = public key exponent! d! = private key exponent! n! = modulus (primes multiplied) m = cd mod n! ! ! the source text is to converted to an integer form that is then passed through the exponent modulus algorithm to create a second integer that can then be converted into a cyphertext string to be transmitted over the network.
- 18. RSA implementation on Arduino implementation of RSA encrypt/decrypt algorithms:! ✤ custom written - mixture of C and assembly (avr only)! ✤ implemented specifically for RSA algorithms! ✤ keys are defined as (n,e) and (n,d) raw bit streams! ✤ designed to be portable with a small code footprint! ✤ 128, 256, 512, 1024 and 2048 keys (if possible)! ✤ limited SRAM of micro controller restricts key sizes
- 19. RSA implementation on Arduino BigInt e, d, n, m, c;! ! // define our public(n,e), private(n,d) and message ! BigInt_assignFromBuffer(&d, (unsigned char *)key_device_prv);! BigInt_assignFromBuffer(&e, (unsigned char *)key_device_pub);! BigInt_assignFromBuffer(&n, (unsigned char *)key_device_mod);! BigInt_assignFromBuffer(&m, (unsigned char *)rsa_message);! ! // encrypt message ‘m’ into cypher text ‘c’! BigInt_exponent_with_modulus(&c, &m, &e, &n);! ! // decrypt cypher text ‘c’ into message ‘m’! BigInt_exponent_with_modulus(&m, &c, &d, &n);!
- 20. IoT Security feasibility - results on the Arduino
- 21. RSA: Arduino UNO ✤ CPU! ✤ ATmega328! ✤ 16Mhz! ✤ 32Kb program mem! ✤ 2Kb SRAM! Performance Results (ms) - compiled with 8bit, pure C algorithm 128 bit 256 bit 512 bit 1024 bit 2048 bit encrypt: public key 288 1070 4103 16160 N/A* decrypt: private key 3155 22365 175452 1383240 N/A* * insufficient SRAM to perform
- 22. RSA: Arduino UNO ✤ CPU! ✤ ATmega328! ✤ 16Mhz! 48% performance boost ✤ 32Kb program mem! ✤ 2Kb SRAM! Performance Results (ms) - compiled with 8bit, avr asm algorithm 128 bit 256 bit 512 bit 1024 bit 2048 bit encrypt: public key 178 609 2225 8504 N/A* decrypt: private key 1951 12716 95079 727955 N/A* * insufficient SRAM to perform
- 23. RSA: Arduino Due ✤ CPU! ✤ AT91SAMX8E! ✤ 84Mhz! ✤ 512Kb program mem! ✤ 96Kb SRAM! Performance Results (ms) - compiled with 32bit, 100% C algorithm 128 bit 256 bit 512 bit 1024 bit 2048 bit encrypt: public key 25 77 264 1032 4122 decrypt: private key 261 1586 11206 88216 701668
- 24. RSA: Arduino Yún ✤ CPU! ✤ ATmega32U4 and AR9331! ✤ 16Mhz and 400Mhz! ✤ 32Kb program mem! ✤ 2.5Kb SRAM! * use Bridge Library to execute RSA algorithms on Linux CPU Performance Results (ms) - compiled with 32bit, 100% C algorithm 128 bit 256 bit 512 bit 1024 bit 2048 bit encrypt: public key 329 355 512 707 N/A* decrypt: private key 437 562 1681 10799 N/A* * insufficient SRAM to perform * the Bridge implementation has a 100-200ms fluctuation in results depending on key size
- 25. RSA: Intel Galileo ✤ CPU! ✤ Quark SoC X1000! ✤ 400Mhz! ✤ 256Kb program mem! ✤ 512Kb SRAM! Performance Results (ms) - compiled with 32bit, 100% C algorithm 128 bit 256 bit 512 bit 1024 bit 2048 bit encrypt: public key 4 20 57 192 706 decrypt: private key 95 397 2310 16055 119499
- 26. RSA: Intel Edison ✤ CPU! ✤ dual core Atom SoC and Quark! ✤ 500Mhz and 100Mhz! ✤ 10Mb program mem! ✤ 1Gb SRAM! Performance Results (ms) - compiled with 32bit, 100% C algorithm 128 bit 256 bit 512 bit 1024 bit 2048 bit encrypt: public key 3 7 23 76 273 decrypt: private key 30 150 976 6548 46579
- 27. RSA 1024: Resource Usage (avr) empty sketch:! Sketch uses 450 bytes (1%) of program storage space. ! Maximum is 32,256 bytes.! Global variables use 9 bytes (0%) of dynamic memory, leaving 2,039 bytes for local variables. Maximum is 2,048 bytes.! ! RSA 1024 with public key only! Sketch uses 4,116 bytes (12%) of program storage space. ! Maximum is 32,256 bytes.! Global variables use 981 bytes (47%) of dynamic memory, leaving 1,067 bytes for local variables. Maximum is 2,048 bytes.! ! resulting code size:! 3,666 bytes of program storage space! 972 bytes of dynamic memory ~ 3.5Kb for code, < 1Kb for RAM
- 28. RSA 1024: Resource Usage (ARM) empty sketch:! Sketch uses 10,492 bytes (2%) of program storage space. ! Maximum is 524,288 bytes.! Global variables use 9 bytes (0%) of dynamic memory, leaving 98,295 bytes for local variables. Maximum is 98,304 bytes.! ! RSA 1024 with public key only! Sketch uses 12,836 bytes (2%) of program storage space. ! Maximum is 524,288 bytes.! Global variables use 981 bytes (0%) of dynamic memory, leaving 97,323 bytes for local variables. Maximum is 98,304 bytes.! ! resulting code size:! 1,454 bytes of program storage space! 972 bytes of dynamic memory ~ 1.4Kb for code, < 1Kb for RAM
- 29. RSA 1024: Resource Usage (x86) empty sketch:! Sketch uses 55,375 bytes (21%) of program storage space. ! Maximum is 262,144 bytes.! Global variables use 9 bytes (0%) of dynamic memory, leaving 524,279 bytes for local variables. Maximum is 524,288 bytes.! ! RSA 1024 with public key only! Sketch uses 63,805 bytes (24%) of program storage space. ! Maximum is 262,144 bytes.! Global variables use 981 bytes (0%) of dynamic memory, leaving 523,307 bytes for local variables. Maximum is 524,288 bytes.! ! resulting code size:! 8,430 bytes of program storage space! 972 bytes of dynamic memory ~ 8.2Kb for code, < 1Kb for RAM
- 31. Configuration Analysis ✤ Advantages! ✤ S_PUB can be dynamic between sessions! ✤ only S_PUB used for encryption, low CPU demands! ! ✤ Disadvantages! ✤ S_PUB is communicated over network! ✤ no good method to validate that the server the device is talking to is authentic (no CA validation)
- 33. Configuration Analysis ✤ Advantages! ✤ S_PUB, D_PUB never communicated over network! ✤ D_PUB is stored on server, associated to UUID! ✤ only Arduino’s registered can communicate with server! ✤ can remove any “compromised” devices from server! ! ✤ Disadvantages! ✤ D_PRV is used to encryption on device = slower
- 34. Secure Random Number Generator ✤ Arduino devices provide at least one analog pin that can be used to create secure random numbers critical for symmetric keys (AES).! ✤ 2-pass von Neumann algorithm to remove “bias” from analog feed! ✤ re-use the existing PRNG random(), seeding at random intervals! ! int secureRandomByte() { static int count = 0; static int next = (randomByte() >> 2) + 1; // max 64 iterations if ((count++ % next) == 0) { randomSeed(randomWord()); next = (randomByte() >> 2) + 1; } return random(256); }
- 35. IoT Security what is the happening the IoT ecosystem?
- 36. Arduino + Secure Wifi Shield ✤ WiFi shield with integrated WINC1500 processor! ! ✤ TLS provided using:! ✤ ECC-256 (eq to RSA-3072)! ✤ AES-128! ✤ SHA-256
- 37. mbed OS - ARM ✤ open source: code/framework designed for Cortex M7
- 38. libCommas - avr https://saifeinc.com/news/?p=223 ! ! ✤ open source: code/framework designed for avr! ✤ ECC (ECDSA) and SHA-2 algorithms! ✤ proprietary server for communication end-point
- 39. AVR crypto-lib - avr http://www.das-labor.org/wiki/AVR-Crypto-Lib/en! ! ✤ open source: code/framework designed for avr! ✤ various block, stream cyphers and hash functions
- 40. IoT Security are we approaching it the right way?
- 41. Security Foundations: Classic Security in computing has been typically bound to the security of the real-world - by defining elements such as keys, trusted-zones (DMZ), firewalls et al.! DMZ
- 42. Security Foundations: Biology Researchers have considered following nature’s design and look at security from with a biological mindset - where devices would be open to infection and evolve.! ! Immunological defence based on identification and isolation of a threat with backup nodes to spawn off to fulfil the function of compromised nodes.! ! http://www.eetindia.co.in/ART_8800705403_1800001_NT_a11862e6.HTM
- 43. Importance of Diversity in Nature http://evolution.berkeley.edu/evolibrary/article/agriculture_02
- 44. How many IoT devices by 2020? ! Gartner:! 26 Billion! Cisco:! ! 50 Billion! ! Intel:! ! 200 Billion! IDC:! ! 220 Billion! It’s time to act now and ensure Security exists within IoT
- 45. Questions
- 46. Contact Information ! ! ! ! [email protected]! www.ardiri.com/blog! www.linkedin.com/in/ardiri