[tor-bugs] #17789 [Tor]: Add syscall-based crypto seeding for OS X

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#17789: Add syscall-based crypto seeding for OS X
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 Reporter:  teor    |          Owner:
     Type:  defect  |         Status:  closed
 Priority:  Medium  |      Milestone:  Tor: 0.2.8.x-final
Component:  Tor     |        Version:  Tor: unspecified
 Severity:  Normal  |     Resolution:  wontfix
 Keywords:          |  Actual Points:
Parent ID:          |         Points:
  Sponsor:          |
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Changes (by teor):

 * status:  new => closed
 * resolution:   => wontfix


Comment:

 Replying to [comment:2 nickm]:
 > (Which is to say, if they include an internal PRNG I'm not too excited
 about them, and if they just wrap open("/dev/random") I'm not too excited
 about them.)

 In fact, those are the exact two options the Apple APIs support!

 They're also not fork()-safe, and they express this by abort()ing on the
 first call in a child after a fork() but before an exec(). This causes
 issues with (misbehaved) tor unit tests that initialise global random
 state, but don't TT_FORK.

 There are ways to work around this, and the commit comment in my branch
 feature17789-v2 describes them. But they're complex, and pointless since
 we're not getting random bytes from the kernel itself.

 Closing as wontfix, until a better Apple API comes along. At that time,
 the code in feature17789-v2 could be useful as a starting point.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/17789#comment:3>
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