[tor-bugs] #5935 [BridgeDB]: Determine how bridge-pool assignments should work with BridgeDB's IPv6 and pluggable-transport extensions

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#5935: Determine how bridge-pool assignments should work with BridgeDB's IPv6 and
pluggable-transport extensions
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 Reporter:  aagbsn    |          Owner:     
     Type:  defect    |         Status:  new
 Priority:  normal    |      Milestone:     
Component:  BridgeDB  |        Version:     
 Keywords:            |         Parent:     
   Points:            |   Actualpoints:     
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Comment(by karsten):

 Replying to [comment:2 asn]:
 > With regards to pluggable transports, there should also be a way to
 specify in which port each pluggable transport is listening (even when a
 bridge supports multiple pluggable transports). In the managed proxy
 protocol, we are specifying this information by using the following
 format:
 > {{{
 > TOR_PT_SERVER_TRANSPORTS=trebuchet,ballista
 > TOR_PT_SERVER_BINDADDR=trebuchet-127.0.0.1:1984,ballista-127.0.0.1:4891
 > }}}
 > it's not particularly nice but it does its job.
 >
 > Also, in the future we might also like to specify an optional arguments
 field for each bridge, so that BridgeDB can pass pluggable transport
 shared-secrets etc. to BridgeDB clients.

 Makes sense.  However, while this is information that BridgeDB needs to
 know to give out to clients, it's not information that BridgeDB needs to
 write to its assignments.log file.  That file should only contain
 information that determines how BridgeDB gives out bridges to clients.
 So, if BridgeDB gets asked for bridges which speak trebuchet and it
 returns a different set of bridges than it would return for other
 requests, that information should go into assignments.log.  But if there
 are no plans to specifically give out trebuchet bridges on port 1984 or to
 weight them any more than other bridges, that information shouldn't go
 into assignments.log.  Shared secrets shouldn't go into assignments.log at
 all.  The purpose of assignments.log is that we can later understand why
 certain bridges see more usage than others.  See #2866 for example.

 I realize that IPv6 and pluggable transport information is something that
 we could also learn from looking at sanitized bridge descriptors.  So, in
 theory, we don't have to include it in assignments.log.  But it's quite
 useful to have all information that BridgeDB uses to make decisions in a
 single place.  It's going to reduce complexity of analyses similar to
 #2866, and that means that more people might want to dive into them.

 So, is a subring of the form `transport=or,obfs2` sufficient to explain
 why BridgeDB gives out a certain subset of bridges to certain BridgeDB
 clients?

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/5935#comment:3>
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