Are there any guidelines or justification for converting a stream cipher algorit

Question

Are there any guidelines or justification for converting a stream cipher algorithm for use as a CSPRNG?

For instance, lets say I wanted to convert one of the eStream portfolio Profile 1 (software) selections for use as a CSPRNG. What I could do is generate a really unique hash from some other algorithm and use it as the key. Then I could generate another really unique, lets say 64-bits, and use it as the initialization variable. Now, what are my options? I could continue regenerating output blocks based on the cipher's internal variables. I could try to encode an incrementing counter into the block stream and then get the output. I could regenerate a key and (iv) and get the output again (seems costly).

I read that it's generally not smart to re-use the key on multiple encodings, so that makes me think I should just keep regenerating the first output block. Is the original output block by definition an unending random stream?

Explanation / Answer

Using a stream cipher for mass generation of "random" bytes is a fairly good solution, however the risk is loosing Forward Secrecy at some point. The trick then is re-keying the cipher often enough, and having a good source of random data with which to rekey your cipher.

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