diff --git a/basis/math/primes/safe/authors.txt b/basis/math/primes/safe/authors.txt new file mode 100644 index 0000000000..b4bd0e7b35 --- /dev/null +++ b/basis/math/primes/safe/authors.txt @@ -0,0 +1 @@ +Doug Coleman \ No newline at end of file diff --git a/basis/math/primes/safe/safe-docs.factor b/basis/math/primes/safe/safe-docs.factor new file mode 100644 index 0000000000..861fc4e4ed --- /dev/null +++ b/basis/math/primes/safe/safe-docs.factor @@ -0,0 +1,38 @@ +! Copyright (C) 2009 Doug Coleman. +! See http://factorcode.org/license.txt for BSD license. +USING: combinators.short-circuit help.markup help.syntax kernel +math math.functions math.primes random ; +IN: math.primes.safe + +HELP: next-safe-prime +{ $values + { "n" integer } + { "q" integer } +} +{ $description "Tests consecutive numbers and returns the next safe prime. A safe prime is desirable in cryptography applications such as Diffie-Hellman and SRP6." } ; + +HELP: random-safe-prime +{ $values + { "numbits" integer } + { "p" integer } +} +{ $description "Returns a safe prime number " { $snippet "numbits" } " bits in length, with the topmost bit set to one." } ; + +HELP: safe-prime? +{ $values + { "q" integer } + { "?" "a boolean" } +} +{ $description "Tests whether the number is a safe prime. A safe prime " { $snippet "p" } " must be prime, as must " { $snippet "(p - 1) / 2" } "." } ; + + +ARTICLE: "math.primes.safe" "Safe prime numbers" +"The " { $vocab-link "math.primes.safe" } " vocabulary implements words to calculate safe prime numbers. Safe primes are of the form p = 2q + 1, where p,q are prime. Safe primes have desirable qualities for cryptographic applications." $nl + +"Testing if a number is a safe prime:" +{ $subsection safe-prime? } +"Generating safe prime numbers:" +{ $subsection next-safe-prime } +{ $subsection random-safe-prime } ; + +ABOUT: "math.primes.safe" diff --git a/basis/math/primes/safe/safe-tests.factor b/basis/math/primes/safe/safe-tests.factor new file mode 100644 index 0000000000..ef9aa9246f --- /dev/null +++ b/basis/math/primes/safe/safe-tests.factor @@ -0,0 +1,14 @@ +! Copyright (C) 2009 Doug Coleman. +! See http://factorcode.org/license.txt for BSD license. +USING: math.primes.safe math.primes.safe.private tools.test ; +IN: math.primes.safe.tests + +[ 863 ] [ 862 next-safe-prime ] unit-test +[ f ] [ 862 safe-prime? ] unit-test +[ t ] [ 7 safe-prime? ] unit-test +[ f ] [ 31 safe-prime? ] unit-test +[ t ] [ 47 safe-prime-candidate? ] unit-test +[ t ] [ 47 safe-prime? ] unit-test +[ t ] [ 863 safe-prime? ] unit-test + +[ 47 ] [ 31 next-safe-prime ] unit-test diff --git a/basis/math/primes/safe/safe.factor b/basis/math/primes/safe/safe.factor new file mode 100644 index 0000000000..a3becb628f --- /dev/null +++ b/basis/math/primes/safe/safe.factor @@ -0,0 +1,29 @@ +! Copyright (C) 2009 Doug Coleman. +! See http://factorcode.org/license.txt for BSD license. +USING: combinators.short-circuit kernel math math.functions +math.primes random ; +IN: math.primes.safe + + + +: safe-prime? ( q -- ? ) + { + [ 1 - 2 / dup integer? [ prime? ] [ drop f ] if ] + [ prime? ] + } 1&& ; + +: next-safe-prime ( n -- q ) + next-safe-prime-candidate + dup safe-prime? [ next-safe-prime ] unless ; + +: random-safe-prime ( numbits -- p ) + random-bits* next-safe-prime ;