I'm trying to build a MUC platform with OMEMO encryption to be used on an Android app. I'm using Ejabberd (v17.11) and Smack library (v4.2.1).
MUC rooms are persistent
and they allow_subscription
for Muc/Sub support, for offline messages.
When a client starts a new room as 'owner' and adds 'member's from his roster; all the clients join the room and everything seem fine. The owner can send messages to the group and it is delivered to every member.
But when a group member tries to send a message, if he doesn't 'know' all the members of the group (if they are not in his roster) he cannot send message!
I found out that, when sending OMEMO message to the group, it is necessary to encrypt the message separately for every member and this necessitates getting every members' devicelist
!
On this step:
mOmemoManager.encrypt(muc, msgBody);
It tries to encrypt for all recipients but fetching an unknown user's device list causes crash.
SENT:
<iq to='[email protected]' id='141' type='get'><query xmlns='http://jabber.org/protocol/disco#info' node='eu.siacs.conversations.axolotl.devicelist'></query></iq>
RECV:
<iq xml:lang='en' to='[email protected]/mobile' from='[email protected]' type='error' id='141'><query node='eu.siacs.conversations.axolotl.devicelist' xmlns='http://jabber.org/protocol/disco#info'/><error code='407' type='auth'><subscription-required xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'/><text xml:lang='en' xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'>Not subscribed</text></error></iq>
Smack's error:
Could not fetch device list of [email protected]: .....
XMPPError: subscription-required - auth
So, how I can solve this? In chat groups every user don't have to meet each other. Should I add everyone to everyone's roster when they come together on a group?
Or is this something about room affiliations or roles?
Or something about Ejabberd configuration?
[{title,<<"groupName">>},
{allow_query_users,true},
{allow_private_messages,true},
{allow_private_messages_from_visitors,anyone},
{allow_visitor_status,true},
{allow_visitor_nickchange,true},
{public,false},
{public_list,false},
{persistent,true},
{moderated,true},
{members_by_default,true},
{members_only,true},
{allow_user_invites,true},
{anonymous,false},
{logging,false},
{allow_voice_requests,true},
{allow_subscription,true},
{mam,true},
{presence_broadcast,[moderator,participant,visitor]},
{voice_request_min_interval,1800},
{vcard,<<>>},
{captcha_whitelist,[]},
{affiliations,[{{<<"user1">>,<<"server.com">>,<<>>},{member,<<>>}}, {{<<"user2">>,<<"server.com">>,<<>>},{owner,<<>>}}, {{<<"user3">>,<<"server.com">>,<<>>},{member,<<>>}}]},
{subject,[]},
{subject_author,<<>>}]