[tor-bugs] #16790 [Tor]: Tor should reload keys from disk when receiving a SIGHUP

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#16790: Tor should reload keys from disk when receiving a SIGHUP
-------------------------+-------------------------------------------------
     Reporter:  s7r      |      Owner:  nickm
         Type:  defect   |     Status:  needs_review
     Priority:  normal   |  Milestone:  Tor: 0.2.7.x-final
    Component:  Tor      |    Version:  Tor: 0.2.7.2-alpha
   Resolution:           |   Keywords:  TorCoreTeam201508, ed25519,
Actual Points:           |  identity keys
       Points:           |  Parent ID:
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Comment (by s7r):

 This doesn't work as expected yet.

 I have created cert and temporary signing key with a lifetime of 2 days
 (the minimum allowed). After 24 hours, I got the normal expected warning:
 {{{
 [notice] It looks like I should try to generate and sign a new medium-term
 signing key, because the one I have is going to expire soon. To do that,
 I'm going to have to try to load the permanent master identity key
 }}}

 This means that Tor should be in the stage when it would reload keys from
 disk when receiving a SIGHUP. It does not, it receives the SIGHUP and
 reloads. I have even deleted all the ed25519* files in $datadirectory/keys
 and sent a SIGHUP. Tor still remembered the cert and signing key loaded
 initially, and only did this:
 {{{
 Aug 24 10:44:54.000 [warn] No key found in
 /root/torsrc/data/keys/ed25519_master_id_secret_key or
 /root/torsrc/data/keys/ed25519_master_id_public_key.
 Aug 24 10:44:54.000 [warn] Master public key was absent; inferring from
 public key in signing certificate and saving to disk.
 }}}
 Only generated and saved to disk ed25519_master_id_public_key and
 continued to run with just with this file in $datadirectory/keys.
 Obviously if I stop it and start again, it will exit since it's missing
 signing key and cert, but sending SIGHUP doesn't do anything, it just
 reloads:
 {{{
 Aug 24 10:52:08.000 [notice] It looks like I should try to generate and
 sign a new medium-term signing key, because the one I have is going to
 expire soon. To do that, I'm going to have to try to load the permanent
 master identity key
 Aug 24 10:52:15.000 [notice] Received reload signal (hup). Reloading
 config and resetting internal state.
 Aug 24 10:52:15.000 [notice] Read configuration file "/root/torsrc/torrc".
 Aug 24 10:52:39.000 [notice] It looks like I should try to generate and
 sign a new medium-term signing key, because the one I have is going to
 expire soon. To do that, I'm going to have to try to load the permanent
 master identity key
 }}}

 Not generating the cert and medium term signing key from memory on SIGHUP
 is not a bug, we actually do not want that behavior. What we want is just
 to call the validation protocol on a SIGHUP, the same as when it starts
 initially.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/16790#comment:7>
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