Opened 6 years ago

Last modified 23 months ago

#9188 new defect

Our weighting algorithms probably behave strangely when guards are disabled

Reported by: nickm Owned by:
Priority: Medium Milestone: Tor: unspecified
Component: Core Tor/Tor Version:
Severity: Normal Keywords: tor-client
Cc: r_a@…, r.a@… Actual Points:
Parent ID: Points:
Reviewer: Sponsor:

Description

Most of our design for weighting and path-selection algorithms includes an assumption that guard nodes are going to get used (since urning off guards in normal use is a really bad idea). But some scanning and measurement tools want to run with guards disabled, and have Tor construct random paths. We should make sure that the random paths Tor generates in that case are sensible.

For example, we currently require the first hop to have the Guard flag, even if UseGuards is off. Is that good? Should we change it? What else do we need here?

Child Tickets

Attachments (1)

tor-dumpguards.patch (2.2 KB) - added by ra 6 years ago.

Download all attachments as: .zip

Change History (10)

comment:1 Changed 6 years ago by ra

Cc: r_a@… added

comment:2 Changed 6 years ago by ra

The attached patch introduces a new control command "DUMPGUARDS" which removes all guard nodes. I am not sure if this generally is the right approach but it "works for me" as it solves the problem that UseGuards=0 produce different paths then UseGuards=1 + DUMPGUARDS.

comment:3 in reply to:  2 Changed 6 years ago by ra

Replying to ra:

solves the problem that UseGuards=0 produce different paths then UseGuards=1 + DUMPGUARDS.

I mean that the problem of path weighting depending on guards being used or not could be avoided by UseGuards=1 + DUMPGUARDS.

Changed 6 years ago by ra

Attachment: tor-dumpguards.patch added

comment:4 Changed 6 years ago by ra

Cc: r.a@… added

comment:5 Changed 6 years ago by nickm

Milestone: Tor: 0.2.5.x-finalTor: 0.2.???

comment:6 Changed 3 years ago by teor

Milestone: Tor: 0.2.???Tor: 0.3.???

Milestone renamed

comment:7 Changed 3 years ago by nickm

Keywords: tor-03-unspecified-201612 added
Milestone: Tor: 0.3.???Tor: unspecified

Finally admitting that 0.3.??? was a euphemism for Tor: unspecified all along.

comment:8 Changed 2 years ago by nickm

Keywords: tor-03-unspecified-201612 removed

Remove an old triaging keyword.

comment:9 Changed 23 months ago by teor

Severity: Normal

Set all open tickets without a severity to "Normal"

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