Forward secrecy (plausible deniability) and storing messages

How do messengers, like signal or XMPP-omemo messengers, store their messages? Since, the session key is only valid for the current session, how can such extensions like MAM (message archiving on XMPP server) or storing the messages encrypted on the disk work? Futher, you often want plausible deniability with malleable encryption and publishing your MAC-Keys. If this happens, how can u be sure that integrity and authentication is still valid?

messages priority

Imagine engine:

submit failed=>error page not found<
page must have1=!httpstatus:404

submit failed has priority

Imagine engine:

submit failed=>error page not found<

modify step=2
modify step condition=httpstatus:404

I didnt check yet, but i guess it is the same? Its not good, or there should be some kind of docs for order of the logic.

Yahoo groups is going away: can I use Mathematica to download the old messages?

It looks like all the old email messages from my group are stored in web pages with URLs that look like this:


That’s email number 19291, and the others have the same form but different numbers at the end. What I am hoping to do is to grab all the old messages. The problem is that:

ans = Import[page] 

returns stuff that begins with “Sorry, an error occurred while loading the content.” From the look of it, I’m guess that the problem is that my Import statement is not “logged in” to the website, and so it is rejecting the request. Does anyone know how to “log in” to the yahoo site (to enable downloading of the old emails)?

Record Header as part of Handshake messages on TCP/IP stack

I knew that the format of the TLS handshake message is as below.

“Record header+Handshake layer header+ Handshake message”

Now i have confusion while analyzing the TLS handshake messages on TCP. How the structure would look like from server in response to client hello.

Note:- Since TCP can handle segmentation i believe server hello,server crt ,server key exchange,server hello done can be handled can be received in segments and provide to tls.

There fore how does the raw date look like at the end of the all frames received till TCP ?

will be it be as below ?

Record header+Handshake layer header+Server hello +Record header+Handshake layer header+Server crt+Record header+Handshake layer header+server key exchange+Record header+Handshake layer header+server hello done

  or will it be omitting the record header ?? 

Record header+Handshake layer header+Server hello +Handshake layer header+Server crt+Handshake layer header+server key exchange+Handshake layer header+server hello done

Byzantine Generals Problem – Oral and Signed Messages

Having just read through Lamport’s paper, I was hoping someone could clarify a few things on the Oral and Signed message algorithms.

  1. Why do we have to run $ OM()$ , recursively by $ m$ ? If a majority of the Lieutenants are loyal, do they not get the correct value by the first round of exchange?
  2. I’m not exactly clear on step 2 of the $ SM()$ algorithm:
  • If Lieutenant $ i$ receives a message of the form $ v : 0 :j_1 : \ldots : Jk$
    and $ v$ is not in the set $ V_i$ , then
    • he adds v to $ V_i$ ;
    • if $ k < m$ , then he sends the message $ v:0 :j_1 :\ldots:j_k : i$ to every
      lieutenant other than $ j_1 \ldots j_k$ .

Does Lieutenant $ i$ only sign a message if $ v$ is not already in $ V_i$ ? Does that mean, there is only one message per value getting $ m$ signatures on the system? Is that what Lamport means, when they prove that a Lieutenant knows when there are no more messages because there can only be one form of each?

Any tips and help is much appreciated!

Copy error or information messages (as text)

In Windows when an error or information box pops up, CtrlC (usually) copies the message into memory. Now you can paste the message into a text file, email, etc using CtrlV.

Very useful when the error is complex or long and you need to report it on sites like StackOverflow!

Is there a similar feature on Ubuntu 18.04 using GNOME? CtrlC does nothing and there is no right-click context menu with a helpful “Copy as text” option.

Here’s an example of the sort of message it would be handy to copy/paste:

enter image description here