Yarrow (algorithm)
The Yarrow algorithm is a cryptographically secure pseudo random number generator . The name comes from the English word Yarrow for the yarrow plant , the dried stems of which are used, for example, for the I Ching prophecy.
Yarrow was designed by Bruce Schneier , John Kelsey and Niels Ferguson in 1999 at Counterpane Labs . The Yarrow algorithm is explicitly unpatented and can be used without license fees .
It is used in macOS and FreeBSD for / dev / random devices, among others .
In their book Practical Cryptography , Schneier and Ferguson describe an advanced version of the algorithm.