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diff --git a/raw-wiki-dump/GitRepositories%2Fcore%2Frng%2Ftrng.trac b/raw-wiki-dump/GitRepositories%2Fcore%2Frng%2Ftrng.trac deleted file mode 100644 index cda0112..0000000 --- a/raw-wiki-dump/GitRepositories%2Fcore%2Frng%2Ftrng.trac +++ /dev/null @@ -1,192 +0,0 @@ -{{{ -#!htmlcomment - -This page is maintained automatically by a script. Don't modify this page by hand, -your changes will just be overwritten the next time the script runs. Talk to your -Friendly Neighborhood Repository Maintainer if you need to change something here. - -}}} - -{{{ -#!html -<h1>trng</h1> - -<p>True Random Number Generator core implemented in Verilog.</p> - -<h2>Introduction</h2> - -<p>This repo contains the design of a True Random Number Generator (TRNG) -for the <a href="http://cryptech.is/">Cryptech OpenHSM</a> project.</p> - -<h2>Design inspiration, ideas and principles</h2> - -<p>The TRNG <strong>MUST</strong> be a really good one. Furthermore it must be trustable -by its users. That means it should not do wild and crazy stuff. And -users should be able to verify that the TRNG works as expected.</p> - -<ul> -<li>Follow best practice</li> -<li>Be conservative - No big untested ideas.</li> -<li>Support transparency - The parts should be testable.</li> -</ul> - -<p>Some of our inspiration comes from: -* The Fortuna RNG by Ferguson and Schneier as described in Cryptography -Engineering.</p> - -<ul> -<li>/dev/random in OpenBSD</li> -</ul> - -<h2>System description</h2> - -<p>The TRNG consists of a chain with three main subsystems</p> - -<ul> -<li>Entropy generation</li> -<li>Entropy mixing</li> -<li>Random generation</li> -</ul> - -<h3>Entropy generation</h3> - -<p>The entropy generation subsystems consists of at least two separate entropy -generators. Each generator collects entropy from an independent physical -process. The entropy sources MUST be of different types. For example -avalance noise from a reversed bias P/N junction as one source and RSSI -LSB from a receiver.</p> - -<p>The reason for having multiple entropy sources is both to provide -redundancy as well as making it harder for an attacker to affect the -entropy collection by forcing the attacker to try and affect different -physical processes simultaneously.</p> - -<p>A given entropy generator is responsible for collecting the entropy -(possibly including A/D conversion.). The entropy generator MUST -implement some on-line testing of the physical entropy source based on -the entropy collected. The tests shall be described in detail here but -will at least include tests for:</p> - -<ul> -<li>No long run lengths in generated values.</li> -<li>Variance that exceeds a given threshhold.</li> -<li>Mean value that don't deviate from expected mean.</li> -<li>Frequency for all possible values are within expected variance.</li> -</ul> - -<p>If the tests fails over a period of generated values the entropy source -MUST raise an error flag. And MAY also block access to the entropy it -otherwise provides.</p> - -<p>There shall also be possible to read out the raw entropy collected from -a given entropy generator. This MUST ONLY be possible in a specific -debug mode when no random generation is allowed. Also the entropy -provided in debug mode MUST NOT be used for later random number -generation. </p> - -<p>The entropy generator SHALL perform whitening on the collected entropy -before providing it as 32-bit values to the entropy accumulator.</p> - -<h3>Entropy mixing</h3> - -<p>The entropy mixer subsystems reads 32-bit words from the entropy -generators to build a block of bits to be mixed.</p> - -<p>When 1024 bits of mixed entropy has been collected the entropy is used -as a message block which is fed into a hash function.</p> - -<p>The hash function used is SHA-512 (NIST FIPS 180-4).</p> - -<p>The digest is then extracted and provided to the random generation as as -a seed.</p> - -<h3>Random generation</h3> - -<p>The random generation consists of a cryptographically secure pseudo random -number generator (CSPRNG). The CSPRNG used in the trng is the stream -cipher ChaCha.</p> - -<p>ChaCha is seeded with:</p> - -<ul> -<li>512 bits block</li> -<li>256 bits key</li> -<li>64 bits IV</li> -<li>64 bits counter</li> -</ul> - -<p>In total the seed used is: 896 bits. This requires getting two seed -blocks of 512 bits from the mixer.</p> - -<p>The number of rounds used in ChaCha is conservatively -selected. We propose that the number of rounds shall be at least 24 -rounds. Possibly 32 rounds. Given the performance in HW for ChaCha and -the size of the keystream block, the TRNG should be able to generate -plentiful of random values even with 32 rounds.</p> - -<p>The random generator shall support the ability to test its functionality -by seeding it with a user supplied value and then generate a number of -values in a specific debug mode. The normal access to generated random -values MUST NOT be allowed during the debug mode. The random generator -MUST also set an error flag during debug mode. Finally, when exiting the -debug mode, reseeding MUST be done.</p> - -<p>Finally the random generator provides random numbers as 32-bit -values. the 512 bit keystream blocks from ChaCha are divided into 16 -32-bit words and provided in sequence.</p> - -<h2>Implementation details</h2> - -<p>The core supports multpiple entropy sources as well as a CSPRNG. For -each entropy source there are some estimators that checks that the -sources are not broken.</p> - -<p>There are also an ability to extract raw entropy as well as inject test -data into the CSPRNG to verify the functionality.</p> - -<p>The core will include one FPGA based entropy source but expects the -other entropy source(s) to be connected on external ports. It is up to -the user/system implementer to provide physical entropy souces. We will -suggest and provide info on how to design at least one such source.</p> - -<p>For simulation there are simplistic fake entropy sources that can be -found in the tb/fake_modules directory. This modules SHOULD NOT be used -as real sources.</p> - -<p>For synthesis there are wrappers for the real entropy source cores to -adapt their interfaces to what we need in the trng. These wrappers -should not be included during simulation.</p> - -<h2>API</h2> - -<p>Normal operation: -* Extract 32-bit random words.</p> - -<p>Config parameters:</p> - -<ul> -<li>Number of blocks in warm-up.</li> -<li>Number of keystream blocks before reseeding.</li> -</ul> - -<p>Debug access</p> - -<ul> -<li>Enable/disable entropy generator X</li> -<li>Check health of entropy generator X</li> -<li>Read raw entropy from entropy generator X as 32-bit word.</li> -<li>Write 256 bit seed value as 8 32-bit words</li> -<li>Read out one or more 512 bit keystream blocks as 32-bit words.</li> -</ul> - -<h2>Status</h2> - -<p><strong>* (2014-09-11) *</strong></p> - -<p>The first version of the CSPRNG is debugged and completed. This version -supports automatic reseeding and an output fifo.</p> -}}} - -[[RepositoryIndex(format=table,glob=core/rng/trng)]] - -|| Clone `https://git.cryptech.is/core/rng/trng.git` || |