Replace MySQL user_name and computer_name column '=5C' with '\'

[satkunas]

Description

Replaces '=5C' with '' in reports for top authentication successes and failures user_name and computer_name.

Impacts

none

Issue

fixes #3508

Delete branch after merge

YES

Bug Fixes

• Backslash in usernames in Reports section is shown as "=5C" (Backslash in usernames in Reports section is shown as "=5C" #3508)

[satkunas]

@julsemaan not tested.

[jrouzierinverse]

freeradius encodes the sql changing special characters to the following format '=6F' where 6F is the hexadecimal representation of the character.

So either this can be done in perl or MySQL

$value =~ s/=([a-fA-F0-9]{2})/chr(hex($1))/ge;

DELIMITER $$

DROP FUNCTION IF EXISTS FREERADIUS_DECODE $$

CREATE FUNCTION FREERADIUS_DECODE (str text) 
RETURNS text
DETERMINISTIC
BEGIN 
    DECLARE result text;
    DECLARE ind INT DEFAULT 0;

    SET result = str;
    WHILE ind <= 255 DO
       SET result = REPLACE(result, CONCAT('=', LPAD(LOWER(HEX(ind)), 2, 0)), CHAR(ind));
       SET result = REPLACE(result, CONCAT('=', LPAD(HEX(ind), 2, 0)), CHAR(ind));
       SET ind = ind + 1;
    END WHILE;

    RETURN result;
END$$

DELIMITER ;

select FREERADIUS_DECODE('=5C') as decoded_value;
+---------------+
| decoded_value |
+---------------+
| \             |
+---------------+

[julsemaan]

I like the second option @jrouzierinverse has suggested since this allows us to integrate it easily in the custom reports

[satkunas]

@julsemaan reworked

Note that db/pf-schema-X.Y.Z.sql does not currently contain any of our stored procedures. This is something we need to discuss before closing this PR.

[julsemaan]

PR looks good to me

@satkunas were you able to test te new code or should this be tested prior to merge?

[julsemaan]

We do put the stored procs in the schema file:
https://github.com/inverse-inc/packetfence/blob/devel/db/pf-schema-X.Y.Z.sql#L647

[satkunas]

@julsemaan added to schema in 988d1b8

[satkunas]

@satkunas were you able to test te new code or should this be tested prior to merge?

@julsemaan not tested fully.

[julsemaan]

Won't be cherry-picking because this contains schema changes