[tor-bugs] #21107 [Core Tor/Tor]: 0.3.0.x dir auths enforcing ED identity keys: intended?

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#21107: 0.3.0.x dir auths enforcing ED identity keys: intended?
------------------------------+--------------------------------
     Reporter:  arma          |      Owner:
         Type:  defect        |     Status:  new
     Priority:  Medium        |  Milestone:
    Component:  Core Tor/Tor  |    Version:  Tor: 0.3.0.1-alpha
     Severity:  Normal        |   Keywords:
Actual Points:                |  Parent ID:
       Points:                |   Reviewer:
      Sponsor:                |
------------------------------+--------------------------------
 Check out the 'atlassky' relay. n-1 dir auths are voting about it because
 they find it to be Running. (I think it is Running.)

 But moria1 is voting only V2Dir, and no other flags. That seems to come
 from:

 {{{
 Dec 29 12:21:44.517 [info] channel_tls_process_versions_cell(): Negotiated
 version 4 with 176.123.26.11:80; Sending cells: CERTS
 Dec 29 12:21:44.517 [info] connection_or_client_learned_peer_id(): learned
 peer id for 0x7f97d5d688f0 (176.123.26.11):
 848878591CAF51274E3A9B71933E9599FA39E122, <null>
 Dec 29 12:21:44.517 [info] dirserv_orconn_tls_done(): Router at
 176.123.26.11:80 with RSA ID 848878591CAF51274E3A9B71933E9599FA39E122 did
 not present expected Ed25519 ID.
 Dec 29 12:21:44.517 [info] channel_tls_process_certs_cell(): Got some good
 certificates from 176.123.26.11:80: Authenticated it with RSA
 Dec 29 12:21:44.517 [info] channel_tls_process_auth_challenge_cell(): Got
 an AUTH_CHALLENGE cell from 176.123.26.11:80: Sending authentication type
 1
 Dec 29 12:21:44.517 [info] channel_tls_process_netinfo_cell(): Got good
 NETINFO cell from 176.123.26.11:80; OR connection is now open, using
 protocol version 4. Its ID digest is
 848878591CAF51274E3A9B71933E9599FA39E122. Our address is apparently
 128.31.0.34.
 }}}

 From the new code in dirserv_orconn_tls_done(), I see
 {{{
     if (! ed_id_rcvd || ! ed25519_pubkey_eq(ed_id_rcvd, expected_id)) {
       log_info(LD_DIRSERV, "Router at %s:%d with RSA ID %s "
                "did not present expected Ed25519 ID.",
                fmt_addr(addr), or_port, hex_str(digest_rcvd, DIGEST_LEN));
       return; /* Don't mark it as reachable. */
     }
 }}}

 So it looks like the dir auths are now enforcing whatever ED key they saw
 from the relay earlier? Is this change intended at this point? If so, is
 there anything we need to do to explain to current relays what they need
 to do or not do?

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/21107>
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