.\" -*- mode: troff; coding: utf-8 -*- .\" Automatically generated by Pod::Man 5.0102 (Pod::Simple 3.45) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>. .ie n \{\ . ds C` "" . ds C' "" 'br\} .el\{\ . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is >0, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{\ . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" ======================================================================== .\" .IX Title "Math::Prime::Util::ChaCha 3pm" .TH Math::Prime::Util::ChaCha 3pm 2024-10-15 "perl v5.40.0" "User Contributed Perl Documentation" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH NAME Math::Prime::Util::ChaCha \- Pure Perl ChaCha20 CSPRNG .SH VERSION .IX Header "VERSION" Version 0.73 .SH SYNOPSIS .IX Header "SYNOPSIS" .SH DESCRIPTION .IX Header "DESCRIPTION" A pure Perl implementation of ChaCha20 with a CSPRNG interface. .SH FUNCTIONS .IX Header "FUNCTIONS" .SS csrand .IX Subsection "csrand" Takes a binary string as input and seeds the internal CSPRNG. .SS srand .IX Subsection "srand" A method for sieving the CSPRNG with a small value. This will not be secure but can be useful for simulations and emulating the system \f(CW\*(C`srand\*(C'\fR. .PP With no argument, chooses a random number, seeds and returns the number. With a single integer argument, seeds and returns the number. .SS irand .IX Subsection "irand" Returns a random 32\-bit integer. .SS irand64 .IX Subsection "irand64" Returns a random 64\-bit integer. .SS random_bytes .IX Subsection "random_bytes" Takes an unsigned number \f(CW\*(C`n\*(C'\fR as input and returns that many random bytes as a single binary string. .SS "" .IX Subsection "" .SH AUTHORS .IX Header "AUTHORS" Dana Jacobsen <dana@acm.org> .SH ACKNOWLEDGEMENTS .IX Header "ACKNOWLEDGEMENTS" Daniel J. Bernstein wrote the ChaCha family of stream ciphers in 2008 as an update to the popular Salsa20 cipher from 2005. .PP RFC7539: "ChaCha20 and Poly1305 for IETF Protocols" was used to create both the C and Perl implementations. Test vectors from that document are used here as well. .PP For final optimizations I got ideas from Christopher Madsen's Crypt::Salsa20 for how to best work around some of Perl's aggressive dynamic typing. Our core is still about 20% slower than Salsa20. .SH COPYRIGHT .IX Header "COPYRIGHT" Copyright 2017 by Dana Jacobsen <dana@acm.org> .PP This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.