Failed to find node for hop 0 of our path. Discarding this circuit.

When I introduce EntryNodes restrictions in my torrc file (also having StrictNodes 1) and then start tor, I get the following rather bizarre sequence going:

[notice] {DIR} We now have enough directory information to build circuits. [notice] {CONTROL} Bootstrapped 80%: Connecting to the Tor network. [warn] {CIRC} Failed to find node for hop 0 of our path. Discarding this circuit. [...ad nauseum...]

If, at this point, I shut down tor and then start it again, without changing anything at all, the bootstrap completes (100% done) and I have no further problems.

My EntryNodes statement isn't very restrictive (something like {DE},{SE},{AT},{EU}), but even if it is, I don't think it should prevent tor from bootstrapping properly.

Trac:
Username: mr-4

changed milestone to %Tor: unspecified

added component::core tor/tor milestone::Tor: unspecified owner::nickm priority::medium reporter::mr-4 resolution::fixed severity::normal status::closed tor-client type::defect version::tor 0.2.4.17-rc labels

Apologies, forgot to add two things: I also have quite extensive "ReachableAddresses reject xx.xx.xx.xx/yy, [...], *:443, *:9001, *:9090-9091" as well as "ExcludeNodes" statements.

The former was introduced at the same time I added my "EntryNodes" statement as described above, the latter has been in my "default-torrc" file for ages.

My "ReachableAddresses reject xx.xx.xx.xx/yy" and ExcludeNodes statements are auto-generated and contain subnets I have completely banned from my network (I have IP firewall rules doing the same), so tor did manage to bootstrap before I included these in torrc.

The reason I put them in my torrc file is to simply let tor know what is banned from my net and what isn't, so that it doesn't waste time trying to connect to nodes/IP addresses which are banned by my firewall.

Trac:
Username: mr-4

Any luck with this one?

Trac:
Username: mr-4

Is anyone actively looking into this???

Trac:
Username: mr-4

This is another one that is going to need a torrc file that can reproduce the behavior before there's much chance of tracking it down.

I'll upgrade to the new tor version (0.2.5.2-alpha) as there was something in the changelogs that suggested this might have been fixed. If not, I'll prepare a set of config & log files and post them here as I did with #10461 (moved) and #10722 (moved)

Trac:
Username: mr-4

Nope! Nothing has changed and I get exactly the same thing.

What I am going to attach next is archive file, which includes my configuration files (defaults-torrc and tor), log files and small readme file with instructions on how to reproduce this bug.

Trac:
Username: mr-4

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Username: mr-4

tor-9972.zip

configuration, log files and readme file with instructions on how to reproduce this bug

Trac:
Username: mr-4

Trac:
Milestone: N/A to Tor: 0.2.5.x-final
Keywords: N/A deleted, tor-client added

Okay, I think I have a fix, but I need to poke it for a while longer to see why the code was doing what it was doing, and whether my fix will break something else.

The first part of this fix is that we need is to change the part of choose_random_entry_impl() that does pick_entry_guards(), so that it says:

  if (! options->UseBridges &&
      smartlist_len(entry_guards) < num_needed)
    pick_entry_guards(options, for_directory);

(But if we do this, what other cases of entry_list_is_constrained() need to change? And does this actually do the right thing?)

(And if we do that, do we need to adjust entry_guards_set_from_config? The *10 there seems pointless and silly now.)

(I've pushed the updated code to branch 'bug9972' for reference, but no guarantees that it's right)

Trac:
Keywords: tor-client deleted, tor-client 025-triaged added

Nick, is this stable-enough to test it? Am I likely to break something on my machine?

Trac:
Username: mr-4

It might be good to test this, but I'm not sure it's right. Back up your state file, keep an eye on what's happening to your guard nodes, and don't count on the set of guard nodes not getting completely trashed while testing this patch.

Hey, I just wanted to add some information regarding this issue. I see these warnings in my log quite often, and I have no restrictions on EntryNodes or anything else. I do run a bridge relay (so BridgeRelay = 1 in my torrc file). Otherwise, my torrc file has been unchanged from the default settings.

Trac:
Username: gatorchomps

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Username: gatorchomps

tor_browser_log

Example of warnings in log file

Trac:
Username: gatorchomps

Also forgot to mention: I run Debian Linux. I'm currently using the 3.6-beta-2 version of TBB, but I received the same warnings when I ran the stable version of the browser, as well.

Trac:
Username: gatorchomps