[tor-bugs] #23819 [Core Tor/Tor]: Support IPv6 link-local interface addresses

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#23819: Support IPv6 link-local interface addresses
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 Reporter:  Zakhar           |          Owner:  (none)
     Type:  enhancement      |         Status:  needs_revision
 Priority:  Medium           |      Milestone:  Tor: 0.3.3.x-final
Component:  Core Tor/Tor     |        Version:
 Severity:  Normal           |     Resolution:
 Keywords:  ipv6 link-local  |  Actual Points:  1
Parent ID:                   |         Points:  1
 Reviewer:                   |        Sponsor:
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Changes (by teor):

 * status:  new => needs_revision
 * milestone:  Tor: unspecified => Tor: 0.3.3.x-final
 * points:   => 1
 * version:  Tor: unspecified =>
 * actualpoints:   => 1


Comment:

 Code review:

 This adds 4 bytes to every address in Tor, just for local addresses.
 Maybe there's a smarter way of doing this?

 We use address types AF_INET and AF_INET6, but there's no type or flag for
 full IPv6 addresses with scopes. We should add a flag or type, so that we
 don't confuse these different types of addresses. (Maybe it's sufficient
 to check if sin6_scope_id is non-zero?)

 Documentation:

 Tor patches need a changes file that contains a short changelog entry for
 the change (see tor/changes/ and `make check-changes`).

 We also need to document this in the manual page under the appropriate
 options.

 Code style:

 We typically put spaces on both sides of the assignment operator:
 {{{
 addr->addr.in6_full.sin6_scope_id= ((struct
 sockaddr_in6*)best->ai_addr)->sin6_scope_id;
 }}}

 Tor has line length limits, run `make check-spaces` to find lines that are
 too long.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/23819#comment:4>
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