Opened 7 years ago

Closed 20 months ago

#8096 closed enhancement (wontfix)

Security factor for steg modules

Reported by: vmon Owned by: zwol
Priority: Low Milestone:
Component: Archived/Stegotorus Version:
Severity: Normal Keywords: steg, archived-closed-2018-07-04
Cc: Actual Points:
Parent ID: Points:
Reviewer: Sponsor:

Description

Implement a security factor for steg modules which controls what prcentage of available capacity of payloads is allowed to be used for embedding data.

This is a simple solution for the user to control the level of indistinguishibility/efficieny according to their sensitivity/DPI power.

This most probably involves employing a pseudorandom walk in the embedding process.

Child Tickets

Change History (4)

comment:1 Changed 6 years ago by vmon

Now Stegotorus takes --minimum-noise-to-signal in command line, and by pass this number to steg. Currently, both implemented payload servers (ApachePayloadServer and TracePayloadServer) respect this value and don't use a cover whose size isn't minimum-noise-to-signal times its capacity, to be used as a cover. For example c.f. trace_payload_server.cc:372

if (pl.typePayloadCap[contentType][current] <= cap
pl.payload_hdrs[pl.typePayload[contentType][current]].length/(double)cap < noise2signal)

continue;

However, it means that file specific steg sub-modules such as (JPEG, JavaScript) only uses the begining of the cover and leave the remainder of the buffer intact. to get a better statistical indistinguishibility, it is desirable for the steg submodule to see if the cover has more capacity than the data to be embeded and if so, it distribute the data uniformly among the changable bytes (for example keying a pseudorandom function to determine the offset of the bytes being used in embedding in contrast to those which stays in tact (due to over capacity).

comment:2 Changed 6 years ago by vmon

Priority: normalminor

comment:3 Changed 2 years ago by teor

Severity: Normal

Set all open tickets without a severity to "Normal"

comment:4 Changed 20 months ago by teor

Keywords: archived-closed-2018-07-04 added
Resolution: wontfix
Status: newclosed

Close all tickets in archived components

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