Ejabberd: Migrating Mnesia "passwd" table to MySQL "user" table - mysql

Question

I have an (old) ejabberd instance that still uses 'internal' as authentication method. I installed a shiny new server (including MySQL) and am planning to migrate to it ASAP. I would like to avoid using Mnesia as authentication DB from then on.
Since my users' passwords are still stored in the Mnesia-database, I need to import them into the (new) MySQL DB on the new server. I succeeded in dumping the 'passwd' table and it is filled with entries like this one:
{passwd,{<<"flowie">>,<<"server.com">>},
{scram,<<"pHHeHwc5yaarPAshse7Ijuygtre=">>,
<<"4Qiv9ygiMLlzeZXUG6Bpyhygtgr=">>,
<<"dylctQFXYGXemMii1Pswe==">>,4096}}
To be able to correctly import these entries into the MySQL DB I need to figure out which field corresponds to which in the MySQL 'users' table:
+----------------+--------------+------+-----+-------------------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------------+--------------+------+-----+-------------------+-------+
| username | varchar(191) | NO | PRI | NULL | |
| password | text | NO | | NULL | |
| serverkey | varchar(64) | NO | | | |
| salt | varchar(64) | NO | | | |
| iterationcount | int(11) | NO | | 0 | |
| created_at | timestamp | NO | | CURRENT_TIMESTAMP | |
+----------------+--------------+------+-----+-------------------+-------+
6 rows in set (0.00 sec)
I obviously know what the 'username' field is (and I think I can guess what the 'iterationcount' would be), but I want to make sure I get the others in the right order.
In one phrase: in what order are the 'password', 'serverkey' and 'salt' fields stored in an ejabberd Mnesia DB ? Where can I find info about this ? In the code perhaps ?
Note for the aspiring hackers among you: I did change the values, using a random character generator ;)

Answer 1

I configured ejabberd 18.03 with the option
auth_password_format: scram
and created an account. Its authentication information is stored like this in Mnesia:
{passwd,{<<"user1">>,<<"localhost">>},
{scram,<<"Eu9adR8M5NPIBoVKK917UKJQTtE=">>,
<<"0mRs0DKWvb8C0/fcVmTRP2elKOA=">>,
<<"UclT113AyXYlUAZgv3q0vA==">>,4096}}
Later I exported Mnesia to a SQL file using the command:
ejabberdctl export2sql localhost /tmp/localhost.sql
and the resulting file contains this line:
INSERT INTO users(username, password, serverkey, salt, iterationcount)
VALUES ('user1',
'Eu9adR8M5NPIBoVKK917UKJQTtE=',
'0mRs0DKWvb8C0/fcVmTRP2elKOA=',
'UclT113AyXYlUAZgv3q0vA==', 4096);