[tor-bugs] #33607 [Core Tor/Tor]: Stop forcing IPv4 and IPv6 traffic on non-SOCKSPorts

[Tor Bug Tracker & Wiki]

#33607: Stop forcing IPv4 and IPv6 traffic on non-SOCKSPorts
--------------------------+------------------------------------
 Reporter:  teor          |          Owner:  (none)
     Type:  defect        |         Status:  new
 Priority:  Medium        |      Milestone:  Tor: 0.4.4.x-final
Component:  Core Tor/Tor  |        Version:
 Severity:  Normal        |     Resolution:
 Keywords:  044-should    |  Actual Points:
Parent ID:                |         Points:  0.1
 Reviewer:                |        Sponsor:
--------------------------+------------------------------------
Description changed by teor:

Old description:

> After #32994, the defaults in `port_cfg_new()` will apply to all parsed
> ports. (Not just default ports.)
>
> I am not sure what we should do with the extra settings in
> `connection_listener_new()`:
> {{{
>   if (type != CONN_TYPE_AP_LISTENER) {
>     lis_conn->entry_cfg.ipv4_traffic = 1;
>     lis_conn->entry_cfg.ipv6_traffic = 1;
>     lis_conn->entry_cfg.prefer_ipv6 = 1;
>   }
> }}}
>
> Here are our options:
> * leave them there: non-SOCKSPorts will always have IPv4, IPv6, and
> prefer IPv6 traffic
> * copy the defaults from port_cfg_new(): non-SOCKSPorts will always have
> DNS, Onion, and prefer IPv6 virtual addresses. Forcing these options on
> might make some configs break.
> * delete them: non-SOCKSPorts can now disable IPv4, IPv6, and prefer IPv4
> traffic. Some rare configs might break, because they relied on the
> options being forced on.
>
> Here's what I think we should do long-term:
> * set reasonable defaults (in #32994)
> * stop forcing options on (this ticket)
> * warn users that some rare configs might break, and they should remove
> NoIPv4Traffic or NoIPv6Traffic as needed (this changes file)
>
> Note that "prefer IPv6 traffic" was added in #32637 in 0.4.3.1-alpha.
> Maybe we don't want to force that option on in this release? I'll open a
> child ticket.

New description:

 After #32994, the defaults in `port_cfg_new()` will apply to all parsed
 ports. (Not just default ports.)

 I am not sure what we should do with the extra settings in
 `connection_listener_new()`:
 {{{
   if (type != CONN_TYPE_AP_LISTENER) {
     lis_conn->entry_cfg.ipv4_traffic = 1;
     lis_conn->entry_cfg.ipv6_traffic = 1;
     lis_conn->entry_cfg.prefer_ipv6 = 1;
   }
 }}}

 Here are our options:
 * leave them there: non-SOCKSPorts will always have IPv4, IPv6, and prefer
 IPv6 traffic
 * copy the defaults from port_cfg_new(): non-SOCKSPorts will always have
 DNS, Onion, and prefer IPv6 virtual addresses. Forcing these options on
 might make some configs break.
 * delete them: non-SOCKSPorts can now disable IPv4, IPv6, and prefer IPv4
 traffic. Some rare configs might break, because they relied on the options
 being forced on.

 Here's what I think we should do long-term:
 * set reasonable defaults (in #32994)
 * stop forcing options on (this ticket)
 * warn users that some rare configs might break, and they should remove
 NoIPv4Traffic or NoIPv6Traffic as needed (this changes file)

 "prefer IPv6 traffic" was added in #32637 in 0.4.3.1-alpha. We don't want
 to force that option on in 0.4.3, that makes the problem worse, and might
 break some existing configs. See #33608 for a fix.

--

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/33607#comment:1>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online