Re: [Trans] Add get_entries_max_limit attribute to get-sth request

[Paul Wouters <[e-mail]>]

On Mon, 4 Feb 2019, Václav Jirovský wrote:

[chair hat on]

We are in the final stages of the bis document, so changing anything
at this point requires a high bar. I haven't seen anyone replying to
this, so that would suggst to me that this is not an item that is that
important to fix right now. If you disagree, please speak out.
Especially those who are implementing this document.

Paul

> Date: Mon, 4 Feb 2019 05:09:35
> From: Václav Jirovský <[e-mail]>
> To: [e-mail]
> Subject: [Trans] Add get_entries_max_limit attribute to get-sth request
> 
> Hello all, 
> I would like to propose modification Retrieve Latest Signed Tree Head section of RFC6962 - adding new attribute get_entries_max_limit.
> 
> Reason for this change - 4.6 section actual version:
>
>  Logs MAY restrict the number of entries that can be retrieved per
>    "get-entries" request.  If a client requests more than the permitted
>    number of entries, the log SHALL return the maximum number of entries
>    permissible.  These entries SHALL be sequential beginning with the
>    entry specified by "start".
> 
> If you want to download all entries from CT server, you don't what number of entries will server return to you by request - so you have to
> process, count real number of returned entries and after that, you can do another request. This is not efficient, you could do these request
> in parallel, if you would have garanteed number of returned entries.
> 
> Proposed modification:
> 
> 4.3.  Retrieve Latest Signed Tree Head
> 
> 
> GET https://<log server>/ct/v1/get-sth
> No inputs.
> 
> Outputs:
>       tree_size:  The size of the tree, in entries, in decimal.
>       timestamp:  The timestamp, in decimal.
>       sha256_root_hash:  The Merkle Tree Hash of the tree, in base64.
>       get_entries_max_limit: Maximum entries count provided by server get-entries method.
>       tree_head_signature:  A TreeHeadSignature for the above data.
> 
> 4.6.  Retrieve Entries from Log
> 
> GET https://<log server>/ct/v1/get-entries
> Inputs:
>       start:  0-based index of first entry to retrieve, in decimal.
>       end:  0-based index of last entry to retrieve, in decimal.
> .....
>
>    Logs MAY restrict the number of entries that can be retrieved per
>    "get-entries" request.  If a client requests more than the permitted
>    number of entries ("get_entries_max_limit" output of "get-sth" request),
>    the log SHALL return the maximum number of entries
>    permissible. If a client requests less or equal than the permitted
>    number of entries ("get_entries_max_limit" output of "get-sth" request),
>    the log MUST return the maximum number of entries permissible.
>    These entries SHALL be sequential beginning with the
>    entry specified by "start".
> Best,
> Vaclav Jirovsky
> 
> 
>