Ora-04079 invalid trigger specification

Question

create or replace trigger ddllog_trigger
after ddl on scott.schema
is
v_user varchar2(1000);
v_loginip varchar2(1000);
v_sqltext v$sqltext_with_newlines%type;
v_sid v$session.sid%type;
v_objname user_objects.object_name%type;
v_objtype user_objects.object_type%type;
v_ddlcommand v$session.command%type;
v_event varchar2(20);
v_num number;
v_errmsg varchar2(1000);
PRAGMA AUTONOMOUS_TRANSACTION;
begin
v_ip := sys_context('userenv', 'ip');
v_errmsg:='Your machine not authenticate to perofrm DDL';
If v_ip = '10.91.104.1'
then
/*session variables */
v_user := sys_context('user_env', 'session_user');
v_sid := sys_context('userenv', 'sid');
v_objname := ora_dict_obj_name;
v_objtype := ora_dict_obj_type;
v_ddlcommand := ora_sysevent;
/*session variables */
/*for building the entire sql text*/
v_num := ora_sql_txt(sql_text);
FOR i IN 1 .. n LOOP
v_sqltext := := v_sqltext := || sql_text(i);
END LOOP;
/*for building the entire sql text*/
/*insert into log*/
insert into ddl_log
(LOGINUSER,
LOGINMC,
SQLTEXT,
OBJECTNAME ,
OBJECTTYPE ,
DDLCOMMAND )
values
(v_user,
v_ip,
v_sqltext,
v_objname,
v_objtype,
v_ddlcommand);
COMMIT;
/*insert into log*/
else
raise_application_error(-20101,v_errmsg);
end;

Answer 1

- v_ip vaiable declaration is missing.
- "end if" is missing before end.
Below is the script of Your Trigger after above all problems been fixed:
create or replace trigger ddllog_trigger
after ddl on schema
declare
v_ip varchar2(100);
v_user varchar2(1000);
v_loginip varchar2(1000);
v_sqltext v$sqltext_with_newlines%type;
v_sid v$session.sid%type;
v_objname user_objects.object_name%type;
v_objtype user_objects.object_type%type;
v_ddlcommand v$session.command%type;
v_event varchar2(20);
v_num number;
v_errmsg varchar2(1000);
PRAGMA AUTONOMOUS_TRANSACTION;
begin
v_ip := sys_context('userenv', 'ip');
v_errmsg:='Your machine not authenticate to perofrm DDL';
If v_ip = '10.91.104.1'             
then
/*session variables */
v_user := sys_context('user_env', 'session_user');
v_sid := sys_context('userenv', 'sid');
v_objname := ora_dict_obj_name;
v_objtype := ora_dict_obj_type;
v_ddlcommand := ora_sysevent;
/*session variables */
/*for building the entire sql text*/
v_num := ora_sql_txt(sql_text);
FOR i IN 1 .. n LOOP
v_sqltext := v_sqltext || sql_text(i);
END LOOP;
/*for building the entire sql text*/
/*insert into log*/
insert into ddl_log
(LOGINUSER,
LOGINMC,
SQLTEXT,
OBJECTNAME ,
OBJECTTYPE ,
DDLCOMMAND )
values
(v_user,
v_ip,
v_sqltext,
v_objname,
v_objtype,
v_ddlcommand);
COMMIT;
/*insert into log*/
else
raise_application_error(-20101,v_errmsg);
end if;
end;Note: Still the trigger script is not completly error free as I can't compile it to check for the rest of errors..     
Regards,
Dipali..