[tor-bugs] #27246 [Core Tor/Tor]: Can we use less space for RSA onion keys on clients?

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#27246: Can we use less space for RSA onion keys on clients?
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 Reporter:  nickm                                |          Owner:  (none)
     Type:  defect                               |         Status:  new
 Priority:  Medium                               |      Milestone:  Tor:
                                                 |  0.3.5.x-final
Component:  Core Tor/Tor                         |        Version:
 Severity:  Normal                               |     Resolution:
 Keywords:  035-roadmap-master, 035-triaged-     |  Actual Points:
  in-20180711                                    |
Parent ID:  #27243                               |         Points:
 Reviewer:                                       |        Sponsor:
                                                 |  Sponsor8
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Comment (by nickm):

 I can confirm that there's a blow-up here -- I ran an experiment with
 openssl to see how much space it uses to store an RSA that it has loaded
 from an ASN1 string.

 The asn.1 string was 140 bytes long. OpenSSL allocated a total of 408
 bytes in order to hold the RSA object and its lock, not counting the
 malloc headers.  (It grabbed one RSA object, one lock, 2 BIGNUM objects,
 and 2 bitvectors inside the BIGNUMs.)

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/27246#comment:1>
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