<div class="gmail_quote">2011/1/29 Michael Stone <span dir="ltr"><<a href="mailto:michael@laptop.org" target="_blank">michael@laptop.org</a>></span><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div><div></div><div>On Fri, 28 Jan 2011 at 14:40:54 -0200 Esteban Bordon wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
I trying to make a notification system that reads messages from sqlite3<br>
database and show them via dbus notifications. I want to store a hash of the<br>
message inside the db to verify each message before show it, but I don't<br>
know how I do it.<br>
<br>
I think sign the message using sig01 of bios-crypto but I don't know how I<br>
can verify this hash. Can I use some mfg-data tag to verify it (msg signed<br>
with masterkey appropiate)?<br>
<br>
Which command I have to use?<br>
</blockquote>
<br></div></div>
Can you please say a bit more about the system you're building? (The choice of<br>
the right command almost certainly depends on some further details about your<br>
goals.)<br>
<br>
In particular:<br>
<br>
* what does a typical message say?<br></blockquote><div><br>Institutional or relevant messages about XO and children. For example, "New OS version is released" or "Your laptop will be blocked tomorrow, please update your blacklist"<br>
</div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
* how are messages transmitted?<br></blockquote><div> </div><div>Laptop download a XML from their school server with the messages.<br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
* are the messages addressed to one, many, or all possible recipients? (unicast, multicast, broadcast)<br></blockquote><div>All laptops should receive the same messages <br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
* are the notifications one-way or will there be replies?<br></blockquote><div>one-way, for now. <br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
* are the messages solely intended for humans to read or are they also<br>
machine readable?<br></blockquote><div>This application is only for humans.<br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
* do you care if other people read the messages in transit? (secrecy)<br></blockquote><div>No matter, messages can be puclic.<br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
* do you care if the messages are modified in transit? (integrity)<br></blockquote><div><br>Yes. It's one reason for I want sign the messages.<br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
* is the recipient supposed to know who sent a message? (agreement on sender identity)<br></blockquote><div>Only school server should to send messages <br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
* is the sender supposed to know who received a message? (agreement on receiver identity)<br></blockquote><div>This feature isn't already implemented <br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
* do you care if a message is never delivered?<br>
(availability / reliability)<br></blockquote><div> If XO connect to server should get the XML. I don't think it as independent messages, all messages are into XML<br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
* do you care if a message is delivered multiple times?<br>
(replay)<br></blockquote><div>No, laptop application delete duplicate messages <br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
* do you care if messages are reordered in transit?<br>
(ordering)<br></blockquote><div> No. the application stores the messages into db file.<br></div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>
* do you have other security goals not mentioned above?<br>
(availability, resource usage limits, non-repudiation, privacy...)<br>
<br>
Regards,<br><font color="#888888">
<br>
Michael<br></font></blockquote><div><br>Regards,<br>Esteban. <br></div></div><br>