Authentication & Session Management questions

Question

Hi. Apex 2.2.1. I'm going crazy trying to set up authentication for my application. I'd appreciate any pointers. My scenario is
Siteminder intercepts all calls to the application
User authenticates with Siteminder
If authenticated, Siteminder sets HTTP_SM_USER in the header
If not authenticated, then APEX is never called
Pull the user out of the header
Create a session if needed
Log the user in if needed
Redirect the user to the request page
I've followed the example that I've found in the forum and set up a page sentry function to create a session when the user first comes in. After that I try to verify that the session belongs to them. That's not working because wwv_flow_custom_auth_std.get_username never returns a value. I think that's because I'm not logging the user in to APEX. I can't figure out the difference between wwv_flow_custom_auth_std.post_login and wwv_flow_custom_auth_std.login. (it probably doesn't help that I inherited the application from some consultants that left a year ago and there is no documentation on it or even APEX here at my site).
Mike

Answer 1

Thanks, Scott. The problem is that it seems to keep looping. You can see from the log that it creates the session, then invalidates it, then creates it, etc.
Mike
debug log
     384     1000     Enter 604 - 1 user MDHENDER session NOT valid
     384     4000     session is NOT valid
     384     4100     dn_network_id is acct\mdhender
     384     5000     creating a new session
     384     5010     created new session
     384     6000     setting up follow up url
     384     6010     follow up url is 604:1:
     384     7000     register new session
     384     7010     registered session
     384     9000     clean exit
     385     1000     Enter 604 - 1 user MDHENDER session valid
     385     3000     session is valid 1707655438517376
     385     3010     authenticated user MDHENDER cookie
     385     3100     marker
     385     3200     marker
     386     1000     Enter 604 - 1 user MDHENDER session NOT valid
     386     4000     session is NOT valid
     386     4100     dn_network_id is acct\mdhender
     386     5000     creating a new session
     386     5010     created new session
     386     6000     setting up follow up url
     386     6010     follow up url is 604:1:
     386     7000     register new session
     386     7010     registered session
     386     9000     clean exit
     387     1000     Enter 604 - 1 user MDHENDER session valid
     387     3000     session is valid 2743127946937676
     387     3010     authenticated user MDHENDER cookie
     387     3100     marker
     387     3200     marker
Here is the code
<code>
CREATE OR REPLACE FUNCTION lmf_siteminder_page_sentry RETURN BOOLEAN IS
vAuthenticatedUsername VARCHAR2(512);
vCurrentSessionId NUMBER;
vDeclaredUser VARCHAR2(512);
vLogFlag VARCHAR2(1);
vMaxIdleMinutes NUMBER := 15;
vNextPage VARCHAR2(1024);
vTransNo NUMBER;
PROCEDURE log_msg(vFlag in varchar2,
vTransNo in number,
vSeqNo in number,
vMessage in varchar2) is
pragma autonomous_transaction;
BEGIN
IF vFlag = 'Y' THEN
insert into sm_debug_log
(transno, seqno, msg)
values
(vTransNo, vSeqNo, vMessage);
commit;
END IF;
EXCEPTION
WHEN OTHERS THEN
rollback;
raise;
END;
-- determine if the siteminder user is authorized
FUNCTION CheckAuthorizedUser(vUserName in varchar2) return boolean is
vDeclaredUser VARCHAR2(512);
BEGIN
-- verify that the user is supposed to have access to the application.
-- a quick check of the authorized users table will settle that question
select dn_network_id
into vDeclaredUser
from user_authorization
where UPPER(network_id) = UPPER(vUserName);
return true;
EXCEPTION
WHEN OTHERS THEN
return false;
END;
-- if the session cookie's user matches our authenticated user then
-- return true
FUNCTION CheckCookieUser(vUserName in varchar2) return boolean is
BEGIN
IF vAuthenticatedUsername = wwv_flow_custom_auth_std.get_username THEN
return true;
END IF;
return false;
END;
FUNCTION URLRedirect(vUrl IN varchar2) return boolean is
BEGIN
log_msg(vLogFlag, vTransNo, 9999, 'redirect => ' || vUrl);
owa_util.redirect_url(vUrl, true);
wwv_flow.g_unrecoverable_error := true;
return false;
END;
BEGIN
BEGIN
select debug, sm_seq_no.nextval
into vLogFlag, vTransNo
from sm_settings;
EXCEPTION
WHEN OTHERS THEN
vLogFlag := 'N';
END;
-- get authenticated user from siteminder. APEX may expect it
-- to be upper case
vAuthenticatedUsername := UPPER(lmf_siteminder_user());
IF wwv_flow_custom_auth_std.is_session_valid THEN
log_msg(vLogFlag,
vTransNo,
1000,
'Enter ' || v('APP_ID') || ' - ' || v('APP_PAGE_ID') ||
' user ' || nvl(vAuthenticatedUsername, '*null*') ||
' session valid');
ELSE
log_msg(vLogFlag,
vTransNo,
1000,
'Enter ' || v('APP_ID') || ' - ' || v('APP_PAGE_ID') ||
' user ' || nvl(vAuthenticatedUsername, '*null*') ||
' session NOT valid');
END IF;
-- no surprise here - let anyone view a page flagged as public
IF htmldb_custom_auth.current_page_is_public THEN
log_msg(vLogFlag, vTransNo, 1010, 'current page is public');
return true;
END IF;
-- redirect all unauthorized users to our no-access page
IF not CheckAuthorizedUser(vAuthenticatedUsername) THEN
-- send the user to our unathorized page
log_msg(vLogFlag,
vTransNo,
1100,
'unable to find dn_network_id for authenticated user ' ||
lmf_siteminder_user());
log_msg(vLogFlag,
vTransNo,
1110,
'try a redirect to ' || '/pls/apex/f?p=' || v('APP_ID') ||
':105:' || vCurrentSessionId || ':');
return URLRedirect('/pls/apex/f?p=' || v('APP_ID') || ':105:' ||
vCurrentSessionId || ':');
END IF;
-- use the current session if it is valid and assigned to
-- our authenticated user
IF wwv_flow_custom_auth_std.is_session_valid THEN
vCurrentSessionId := wwv_flow_custom_auth_std.get_session_id_from_cookie;
log_msg(vLogFlag,
vTransNo,
3000,
'session is valid ' || vCurrentSessionId);
log_msg(vLogFlag,
vTransNo,
3010,
'authenticated user ' || vAuthenticatedUsername || ' cookie ' ||
wwv_flow_custom_auth_std.get_username);
-- if the session cookie's user matches our authenticated user then
-- accept it and proceed with displaying the page
IF CheckCookieUser(vAuthenticatedUsername) THEN
wwv_flow_custom_auth.define_user_session(p_user => vAuthenticatedUsername,
p_session_id => vCurrentSessionId);
return true;
END IF;
log_msg(vLogFlag, vTransNo, 3100, 'marker');
-- the names do not match. assume that someone hijacked the session.
-- invalidate it and bump them out
-- Unset the session cookie and redirect back here to take other branch
wwv_flow_custom_auth_std.logout(p_this_flow => v('APP_ID'),
p_next_flow_page_sess => v('APP_ID') || ':' ||
nvl(v('APP_PAGE_ID'),
0) || ':' ||
vCurrentSessionId);
wwv_flow.g_unrecoverable_error := true;
log_msg(vLogFlag, vTransNo, 3200, 'marker');
-- tell APEX that we are not pleased
return false;
END IF;
log_msg(vLogFlag, vTransNo, 4000, 'session is NOT valid');
-- we did not have a valid session so verify that the user is supposed
-- to access our application. a quick check of the authorized users
-- table will settle that question for us
BEGIN
select dn_network_id
into vDeclaredUser
from user_authorization
where UPPER(network_id) = vAuthenticatedUsername;
log_msg(vLogFlag, vTransNo, 4100, 'dn_network_id is ' || vDeclaredUser);
EXCEPTION
WHEN NO_DATA_FOUND THEN
-- send the user to our unathorized page
log_msg(vLogFlag,
vTransNo,
4900,
'unable to find dn_network_id for authenticated user ' ||
vDeclaredUser);
log_msg(vLogFlag,
vTransNo,
4910,
'try a redirect to ' || '/pls/apex/f?p=' || v('APP_ID') ||
':105:' || vCurrentSessionId || ':');
return URLRedirect('/pls/apex/f?p=' || v('APP_ID') || ':105:' ||
vCurrentSessionId || ':');
END;
-- create new session
log_msg(vLogFlag, vTransNo, 5000, 'creating a new session');
wwv_flow_custom_auth.define_user_session(p_user => vAuthenticatedUsername,
p_session_id => wwv_flow_custom_auth.get_next_session_id);
log_msg(vLogFlag, vTransNo, 5010, 'created new session');
wwv_flow.g_unrecoverable_error := true;
-- set cookie
-- set the followup URL to page 1
log_msg(vLogFlag, vTransNo, 6000, 'setting up follow up url');
vNextPage := to_char(wwv_flow.g_flow_id) || ':1:';
log_msg(vLogFlag, vTransNo, 6010, 'follow up url is ' || vNextPage);
--wwv_flow_custom_auth.remember_deep_link(p_url => vNextPage);
--log_msg(vLogFlag, vTransNo, 6020, 'completed follow up url');
--IF owa_util.get_cgi_env('REQUEST_METHOD') = 'GET' THEN
-- wwv_flow_custom_auth.remember_deep_link(p_url => 'f?' ||
-- wwv_flow_utilities.url_decode2(owa_util.get_cgi_env('QUERY_STRING')));
--ELSE
-- wwv_flow_custom_auth.remember_deep_link(p_url => 'f?p=' ||
-- to_char(wwv_flow.g_flow_id) || ':' ||
-- to_char(nvl(wwv_flow.g_flow_step_id,
-- 0)) || ':' ||
-- to_char(wwv_flow.g_instance));
--END IF;
-- register new session with the application
log_msg(vLogFlag, vTransNo, 7000, 'register new session');
if 0 < 1 then
wwv_flow_custom_auth_std.post_login(p_uname => vAuthenticatedUsername,
p_flow_page => vNextPage);
log_msg(vLogFlag, vTransNo, 7010, 'registered session');
else
wwv_flow_custom_auth_std.login(P_UNAME => vAuthenticatedUsername,
P_PASSWORD => 'dummy',
P_SESSION_ID => v('APP_SESSION'),
P_FLOW_PAGE => v('APP_ID') || ':1');
log_msg(vLogFlag, vTransNo, 7011, 'registered session');
end if;
if 0 > 1 then
owa_util.mime_header('text/html', FALSE);
owa_cookie.send(name => 'LOGIN_USERNAME_COOKIE',
value => vAuthenticatedUsername,
expires => null,
path => '/',
secure => 'yes');
owa_cookie.send(name => 'HTMLDB_IDLE_SESSION',
value => to_char(sysdate + (vMaxIdleMinutes / 1440),
'DD-MON-YYYY HH24:MI:SS'),
expires => null,
path => '/',
secure => 'yes');
end if;
log_msg(vLogFlag, vTransNo, 9000, 'clean exit');
-- tell htmldb engine to quit
return false;
EXCEPTION
WHEN OTHERS THEN
return false;
END;
</code>