On Fri, 7 Sep 2007, Stephen Harris wrote:
The traditional crypt strings are from a limited set 64 characters and are always 13 characters long. GNU libc can use md5 based encryption (the first 3 characters are $1$ and are up to 34 characters in length) but are still from the character set [a-zA-Z0-9./]
The openssl binary can easily create a shadow-compatible hash for you:
openssl passwd -1