Net::SSH::Perl has a perl-only implementation of SSH-1 and SSH-2, with a variety of authentications schemes. The docs identify some performance advantages to being all perl, but more relevant here they say

It also simplifies the process of using password-based authentications; when writing a wrapper around ssh you probably need to use Expect to control the ssh client and give it your password. Net::SSH::Perl has built-in support for the authentication protocols, so there's no longer any hassle of communicating with any external processes.