allowedNetworks: hardcoded IPv4 format, even with IPv6 enabled

Plex Media Server
,
1

Server Version#: 1.23.2.4600
Player Version#: — irrelevant —

In parsing of allowedNetworks preference, a inet_pton (AF_INET6) case is missing:

Request: [192.168.178.34:56086 (Allowed Network (Subnet))] PUT /:/prefs?allowedNetworks=fe80%2F8 (13 live) GZIP Signed-in Token (…@googlemail.com)
Error parsing allowedNetworks 'fe808': Invalid argument

Other calls to inet_pton check with AF_INET6 first, then fall back to AF_INET if not parsed. Only

  • TreatWanIpAsLocal parsing
  • the loop "Comparing request from %s against %s/%s" for allowedNetworks(?)
  • allowedNetworks parsing

call the function only with AF_INET.

Since IPv6 addresses do reach the server even with EnableIPv6=0, this implies it is impossible to allow devices that prefer IPv6.

As a side note, the exception is missing the / since it is replaced with a '\0', which might be misleading when reading the error.

2

Would you please also show what you entered in “Allowed Networks” so I may give Engineering the example of what causes the failure ?

that aside, I am almost 100% certain, IPv6 isn’t fully supported.

I know plex.tv has no IPv6 support. Only www.plex.tv (general web page) is IPv6 capable.

3

Yeah, I don’t actually want to use IPv6, but one of my devices insists and Plex seems to listen on v6 as well, not just v4, and I can’t seem to get either to stop doing that…

My input was fe80::c73:bd9b:28a:1159 as a concrete IP and fe80::/10 for the “all locals” range. As per man inet_pton these are valid inputs for inet_pton (AF_INET6):

  1. The preferred format is x:x:x:x:x:x:x:x. This form consists of eight hexadecimal numbers, each of which expresses a 16-bit value (i.e., each x can be up to 4 hex digits).
  2. A series of contiguous zero values in the preferred format can be abbreviated to ::. Only one instance of :: can occur in an address. For example, the loopback address 0:0:0:0:0:0:0:1 can be abbreviated as ::1. The wildcard address, consisting of all zeros, can be written as ::.
  3. An alternate format is useful for expressing IPv4-mapped IPv6 addresses. This form is written as x:x:x:x:x:x:d.d.d.d, where the six leading XS are hexadecimal values that define the six most-significant 16-bit pieces of the address (i.e., 96 bits), and the ds express a value in dotted-decimal notation that defines the least significant 32 bits of the address. An example of such an address is ::FFFF:204.152.189.116.
4

Thank you.

May I ask which Manufacturer made the device ?

5

I had issues with both Apple devices and an old cheap no-name Android tablet of a friend. I convinced the Apple one by manually configuring an empty address for IPv6, but that doesn’t sound like a real solution either…

6

I have multiple Apple devices. In fact, I have no Android.

Does your modem/router support dual-stack TCP/IP ?

Followup to that, does it support dual-stack DHCP services for the devices ?

I am asking because:

  1. My Modem/router is dual stack
  2. My workstation is dual stack.
  3. All my home devices are RFC-1918 IPv4 (including every Apple device)
7

The iOS devices seem to be defaulting to IPv4 in my setup, the iMac for some reason to IPv6, but only sometimes?! I had one tab logged in, using IPv4, and another (to test, incognito) using IPv6.

My setup is a “bit” of a mess. Answering your post and drawing a diagram made me realize just how bonkers it is… Thanks.

= WAN ===+==
         | (IPv6 disabled)
     FRITZ!Box 5490 (router)
         |       |
= LAN ===+====== ( ===========+====================+==
         |       |            |                    |
         |       |  Apple Time Capsule (bridge)    |
         |       |            |           |        |
= LAN 2= ( ===== ( ======+====+==         |      iMac
         |       |       |                |        |
         |       |  Synology DS920 (plex) |        |
         |       |          |             |        |
= WiFi ==+====== ( ======== ( =========== ( =======?======?==
                 |          |             |        |      |
= Guest LAN    ==+==========+==           |        |      |
= Guest WiFi 1 ==+===+=================== ( =======?======?=============?==
                     |                    |        |      |             |
                Apple TV gen3             |        |  private iOS   guest/work
                                          |        |      |             |
= Guest WiFi 2 ===========================+========?======?=============?==
  • The FRITZ!Box does not allow configuring IPv6 for local networks if it is disabled on the WAN side.
  • The issue is probably the secondary Guest WiFi I have for legacy reasons: The Time Capsule (in Bridge mode) seems to like IPv6. The TC complains if WiFi is turned off though…
  • My private WiFI-capable devices randomly connect to the WiFis (since all are saved and thing are magic™), which likely is where the TC IPv6 comes into play and breaks things.

tl;dr I should probably clean this up… What the hell was I thinking. I have less complex configurations with 200+ devices at work.

8

My TL;DR :slight_smile:

I wish you luck.

Once you get that flattened out, you’ll be a lot happier.