Пакет perl-Crypt-Random-Seed: Информация
Исходный пакет: perl-Crypt-Random-Seed
Версия: 0.03-alt2
Собран: 19 февраля 2014 г. 3:49 в задании #114763
Категория: Разработка/Perl
Сообщить об ошибке в пакетеДомашняя страница: https://github.com/danaj/Crypt-Random-Seed
Лицензия: perl
О пакете: Provide strong randomness for seeding
Описание:
A simple mechanism to get strong randomness. The main purpose of this.module is to provide a simple way to generate a seed for a PRNG such as the Math::Random::ISAAC manpage, for use in cryptographic key generation, or as the seed for an upstream module such as the Bytes::Random::Secure manpage. Flags for requiring non-blocking sources are allowed, as well as a very simple method for plugging in a source. The randomness sources used are, in order: =over 4 =item User supplied. If the constructor is called with a Source defined, then it is used. It is not checked vs. other flags (NonBlocking, Never, Only). =item Win32 Crypto API. This will use `CryptGenRandom' on Windows 2000 and `RtlGenRand' on Windows XP and newer. According to MSDN, these are well-seeded CSPRNGs (FIPS 186-2 or AES-CTR), so will be non-blocking. =item EGD / PRNGD. This looks for sockets that speak the EGD protocol, including PRNGD. These are userspace entropy daemons that are commonly used by OpenSSL, OpenSSH, and GnuGP. The locations searched are `/var/run/egd-pool', `/dev/egd-pool', `/etc/egd-pool', and `/etc/entropy'. EGD is blocking, while PRNGD is non-blocking (like the Win32 API, it is really a seeded CSPRNG). However there is no way to tell them apart, so we treat it as blocking. If your O/S supports /dev/random, consider HAVEGED as an alternative (a system daemon that refills /dev/random as needed). =item /dev/random. The strong source of randomness on most UNIX-like systems. Cygwin uses this, though it maps to the Win32 API. On almost all systems this is a blocking source of randomness -- if it runs out of estimated entropy, it will hang until more has come into the system. If this is an issue, which it often is on embedded devices, running a tool such as HAVEGED will help immensely. =item /dev/urandom. A nonblocking source of randomness that we label as weak, since it will continue providing output even if the actual entropy has been exhausted. =item TESHA2. the Crypt::Random::TESHA2 manpage is a Perl module that generates random bytes from an entropy pool fed with timer/scheduler variations. Measurements and tests are performed on installation to determine whether the source is considered strong or weak. This is entirely in portable userspace, which is good for ease of use, but really requires user verification that it is working as expected if we expect it to be strong. The concept is similar to the Math::TrulyRandom manpage though updated to something closer to what TrueRand 2.1 does vs. the obsolete version 1 that the Math::TrulyRandom manpage implements. It is very slow and has wide speed variability across platforms : I've seen numbers ranging from 40 to 150,000 bits per second. =back A source can also be supplied in the constructor. Each of these sources will have its debatable points about perceived strength. E.g. Why is /dev/urandom considered weak while Win32 is strong? Can any userspace method such as TrueRand or TESHA2 be considered strong?
Сопровождающий: Igor Vlasenko
Последнее изменение
19 февраля 2014 г. Igor Vlasenko 0.03-alt2
- moved to Sisyphus for Slic3r (by dd@ request)
9 октября 2013 г. Igor Vlasenko 0.03-alt1
- initial import by package builder