[tor-bugs] #4900 [Tor Relay]: Use a more randomized hash function for our hash tables

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#4900: Use a more randomized hash function for our hash tables
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 Reporter:  nickm         |          Owner:                    
     Type:  defect        |         Status:  new               
 Priority:  normal        |      Milestone:  Tor: 0.2.3.x-final
Component:  Tor Relay     |        Version:                    
 Keywords:  dos security  |         Parent:                    
   Points:                |   Actualpoints:                    
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Comment(by nickm):

 I've got the start of a proof-of-concept in bug4900 in my public repo.
 Trouble is, it crashes Tor on startup, because we need to set a global
 seed before we put anything into a hash table, but we can't get a good
 seed until we've initialized openssl.  More hacking needed.

 The good news here is that this change doesn't seem to slow stuff down
 much. ./src/test/bench reports about a 4-5% slowdown in digestmap
 operations on my 32-bit laptop.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/4900#comment:1>
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