Subject: Re: SSH2 host key length and hash compute

Re: SSH2 host key length and hash compute

From: Alexander Lamaison <>
Date: Tue, 2 Jul 2013 09:57:53 +0100

On 2 July 2013 07:34, Kalpesh Parekh <> wrote:
> Hi Alex
> The APIs I am using are libssh2_session_hostkey to retreive the host key and
> libssh2_hostkey_hash to compute the hash from the key.
> The first API returns the length of the host key in a variable passed to it
> as a function argument. The variable is of size_t type and indicates the
> size of host key. I need to convert this value to bits. Can you let me know
> how can I do this?

Why do you need to convert it to bits? What does that actually mean?
The size_t length is just a number.

> This variable is passed to the second api and the hash is returned.

Have you read the documentation?

The two functions are unrelated. You do not pass the output from one
as the input to the other.

> Here
> based on the type of host key, if it is RSA I request for the md5 hash and
> sha1 hash for DSS key. Let me know if my assumption is correct here

You can request MD5 or SHA1, as you wish, independent of the key type.


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Received on 2013-07-02