NAME
qsieve,
qsafe —
generate system moduli file
SYNOPSIS
qsieve |
[megabytes
bits
[initial]] |
qsafe |
[trials
[generator]] |
DESCRIPTION
The
qsieve utility will list candidates for Sophie-Germaine
primes (where q = (p-1)/2) to standard output. The list is checked against
small known primes (less than 2**30). This step is both processor and memory
intensive.
The
megabytes value sets a limit for the internal sieve
buffer. This should be small enough to remain entirely in memory. Swap
thrashing can increase the run time from hours to days or weeks! When the
megabytes value is zero (0),
qsieve
will select a default suitable for the
bits.
The
bits value sets the length of the generated possible
primes (typically 768, 1024, 1536, 2048, 3072, or 4096, although others can be
used for variety).
The optional
initial value (hex) specifies the beginning
of the search. Otherwise,
qsieve generates a randomly
selected number.
The
qsafe utility will perform a Miller-Rabin primality test
on the list of candidates (checking both q and p) from standard input. The
result is a list of so-call "safe" primes to standard output,
suitable for use as Diffie-Hellman moduli. This step is merely processor
intensive.
The
trials value sets the number of Miller-Rabin
interations (typically 16 to 128).
The optional
generator value (hex) limits testing to
candidates with a specific generator (usually 2). Otherwise,
qsafe will test each candidate and suggest a generator.
SEE ALSO
moduli(5)
HISTORY
These programs were originally developed for the Photuris project, and later the
OpenSSH project.