[tor-bugs] #13267 [Onionoo]: escaped forward slashes in contact info

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#13267: escaped forward slashes in contact info
---------------------------+----------------------------
     Reporter:  Sebastian  |      Owner:
         Type:  defect     |     Status:  needs_revision
     Priority:  normal     |  Milestone:
    Component:  Onionoo    |    Version:
   Resolution:             |   Keywords:
Actual Points:             |  Parent ID:
       Points:             |
---------------------------+----------------------------
Changes (by karsten):

 * status:  new => needs_revision


Comment:

 Good catch, Sebastian, and thanks for the patch, iwakeh.  But we have to
 be careful when fixing this problem.  Let me explain:

 Here's a server descriptor published by another currently running relay,
 particularly the only relay that I found that has both characters `/` and
 `'` in its contact line:

 {{{
 router DigitalBrains 83.161.152.50 21 0 0
 or-address [2001:980:a370::8]:80
 platform Tor 0.2.4.23 on Linux
 protocols Link 1 2 Circuit 1
 published 2014-09-28 06:57:28
 fingerprint B41E 3847 4992 3487 4688 B2F3 54C6 764B 8589 EAF8
 uptime 718153
 bandwidth 1572864 10485760 2790125
 extra-info-digest 7201355DF31896829B95CB970A63CD4D6BCFE93B
 onion-key
 -----BEGIN RSA PUBLIC KEY-----
 MIGJAoGBAKcLROc5/W6X7bsL5XX3+miireX/kU8HW2mC+Yp3OVD2bqccP++kZCUj
 XWWEjWv4nUJ8OnbbFAFey4+/Oe7cIoySqfOgQK04iIiU8JTs1/16vtjYLPSGg2JW
 kZrvWIsHlX1+/4y1PRnjr0VdHgxQKfuDS/Rc4+HtUNcqbFo5QqpbAgMBAAE=
 -----END RSA PUBLIC KEY-----
 signing-key
 -----BEGIN RSA PUBLIC KEY-----
 MIGJAoGBAMT/Ev+LaTTtvmn+4zO3/w4XYcJTDdG7r+5G4Jsgkz3AwmMm6fUKZON5
 QKDA3osPoC+R6sRR0PoWnXkWgab4nCOtVdzA9zyrcNHuMo4jFyhfO0QYK3jok+wv
 oFhWygCleT0XIWtVrWCoA2kmM5iQpcfSry830cA2iwasRx9qNSVzAgMBAAE=
 -----END RSA PUBLIC KEY-----
 hidden-service-dir
 contact 2048R/DE500B3E Peter Lebbing <tormail at (this router's nickname)
 dot com>
 ntor-onion-key 39Iw4BEaOdFRfvLo2Ko1Eg3iLS54jKSr1SwcBpcBP3Y=
 reject *:*
 router-signature
 -----BEGIN SIGNATURE-----
 BJqOVb7/EACgyNf1LpuyDcWT5hHoFrsPOY0+GoyQwPyh5ejruCwju856aZ7yVoJk
 Iv2adms2ONiXFtAlTawTybptcpgXGmNaTXAeWnyFMdrYpWVkej0Ha2zHVl7hXJoH
 5cKnN3SNYvqdxXdtBM9bnyPLfyvlqTnmPlKRTrV3W/g=
 -----END SIGNATURE-----
 }}}

 The hourly cronjob has a first phase during which it writes descriptor
 contents to a details status file.  Here's what it writes for this
 particular relay:

 {{{
 "desc_published": "2014-09-29 06:51:59",
 "last_restarted": "2014-09-19 23:28:14",
 "bandwidth_rate": 1572864,
 "bandwidth_burst": 10485760,
 "observed_bandwidth": 3127441,
 "advertised_bandwidth": 1572864,
 "exit_policy": [
     "reject *:*"
 ],
 "contact": "2048R\\/DE500B3E Peter Lebbing <tormail at (this router's
 nickname) dot com>",
 "platform": "Tor 0.2.4.23 on Linux"
 }}}

 During the second phase the hourly cronjob reads details status files and
 writes them to details documents which will later be copied verbatim to
 servlet responses.  Here's the relay's details document:

 {{{
 {
     "nickname": "DigitalBrains",
     "fingerprint": "B41E3847499234874688B2F354C6764B8589EAF8",
     "or_addresses": [
         "83.161.152.50:21",
         "[2001:980:a370::8]:80"
     ],
     "last_seen": "2014-09-29 08:00:00",
     "last_changed_address_or_port": "2014-09-26 09:00:00",
     "first_seen": "2014-09-26 09:00:00",
     "running": true,
     "flags": [
         "Fast",
         "Guard",
         "Running",
         "Stable",
         "Valid"
     ],
     "country": "nl",
     "country_name": "Netherlands",
     "latitude": 52.5,
     "longitude": 5.75,
     "as_number": "AS3265",
     "as_name": "XS4ALL Internet BV",
     "consensus_weight": 3400,
     "last_restarted": "2014-09-19 23:28:14",
     "bandwidth_rate": 1572864,
     "bandwidth_burst": 10485760,
     "observed_bandwidth": 3127441,
     "advertised_bandwidth": 1572864,
     "exit_policy": [
         "reject *:*"
     ],
     "exit_policy_summary": {
         "reject": [
             "1-65535"
         ]
     },
     "contact": "2048R\\/DE500B3E Peter Lebbing <tormail at (this router's
 nickname) dot com>",
     "platform": "Tor 0.2.4.23 on Linux",
     "advertised_bandwidth_fraction": 0.00012835582,
     "consensus_weight_fraction": 0.0001344956,
     "guard_probability": 0.0002506447,
     "middle_probability": 0.00015283491,
     "exit_probability": 0,
     "recommended_version": true
 }
 }}}

 The easy fix would be to update the `escapeJSON` and `unescapeJSON`
 methods in `DetailsDocument` similar to iwakeh's patch.  Newly written
 details documents would then not contain escaped forward slashes anymore.
 (There's no easy way to force rewriting details documents, but we could
 write a simple script or Java tool that goes over all files in
 `out/details/`, removes backslashes, and rewrites files.)

 The harder fix would be to also apply iwakeh's patch.  The reason is that
 the hourly cronjob would read old and new details status files, and it
 wouldn't handle old status files correctly.  (I didn't go through all
 steps there, but I '''think''' this would break.)  So, we'd have to first
 go through all old status files and update them and then apply the patch.
 This needs testing before we should apply it to the production system.
 Plus, we'll also have to do the easy fix to `DetailsDocument`, or our
 changes won't be effective at all.

 iwakeh, would you want to prepare a revised patch and test it on a local
 Onionoo instance?

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/13267#comment:3>
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