Bumping this as I haven't heard back.  Any thoughts?

From: Johnson, Eric C
Sent: Friday, January 13, 2012 11:29 AM
To: '[email protected]'
Subject: Question regarding failed Child SA response

I have a scenario where I'm trying to establish a cert based tunnel between two 
hosts (one using Strongswan and the other not) using IKEv2.

I inadvertently created an ID mismatch on the initiating Strongswan host.  For 
example, on the Ubuntu host I configured the rightid value as 
[email protected]<mailto:[email protected]> but on the remote peer I had a local 
certificate with a Subject Alternative Name (SAN) value of host.domain.com.  
Basically I misconfigured the peers where one was expecting the email SAN type 
while the other was sending the dns SAN type.  The good news is I understand 
the problem and have managed to get things working.  What I don't understand is 
the behavior to account for this configuration issue.  During the Child SA 
exchange the Strongswan host sends the request and the remote peer sends the 
corresponding Child SA response.  But due to the misconfiguration, the Child SA 
response essentially fails.  However, the remote peer thinks the tunnel is up 
while the Strongswan host does not.  And I can't determine if this is 
appropriate behavior or not.  It seems like there should be some mechanism 
built into the IKEv2 protocol to accommodate a failed Child SA response.  My 
initial reaction is the Strongswan host should be sending a notification 
message to the remote peer to inform it the tunnel is not fully established and 
to clean up the Child SAs so a new request can be sent.  But I never see a 
notify message or a new request sent from the Strongswan host.

Following are the relevant log entries from the Strongswan initiating attempt 
(I have removed the majority of the entries for security reasons) ...
|
Jan 13 10:55:42 gyaos6-PowerEdge-R610 charon: 08[CFG]   fetching crl from 
'file://\\StandAloneCA\CertEnroll\sqaca.crl' ...
Jan 13 10:55:42 gyaos6-PowerEdge-R610 charon: 08[LIB] libcurl http request 
failed: Couldn't open file 
\\StandAloneCA\CertEnroll\sqaca.crl<file:///\\StandAloneCA\CertEnroll\sqaca.crl>
Jan 13 10:55:42 gyaos6-PowerEdge-R610 charon: 08[CFG] crl fetching failed
Jan 13 10:55:42 gyaos6-PowerEdge-R610 charon: 08[CFG]   fetching crl from 
'http://standaloneca/CertEnroll/sqaca.crl' ...
Jan 13 10:55:42 gyaos6-PowerEdge-R610 charon: 08[LIB] libcurl http request 
failed: Couldn't resolve host 'standaloneca'
Jan 13 10:55:42 gyaos6-PowerEdge-R610 charon: 08[CFG] crl fetching failed
Jan 13 10:55:42 gyaos6-PowerEdge-R610 charon: 08[CFG] certificate status is not 
available
Jan 13 10:55:42 gyaos6-PowerEdge-R610 charon: 08[CFG]   reached self-signed 
root ca with a path length of 0
Jan 13 10:55:42 gyaos6-PowerEdge-R610 charon: 08[IKE] authentication of 
'<host.domain.com>' with RSA signature successful
Jan 13 10:55:42 gyaos6-PowerEdge-R610 charon: 08[CFG] constraint check failed: 
identity '< [email protected]<mailto:[email protected]> >' required
Jan 13 10:55:42 gyaos6-PowerEdge-R610 charon: 08[CFG] selected peer config 
'ubuntu-gamera6_ipv4_wka' inacceptable
Jan 13 10:55:42 gyaos6-PowerEdge-R610 charon: 08[CFG] no alternative config 
found
Jan 13 10:55:50 gyaos6-PowerEdge-R610 kernel: [1557141.489236] device eth0 left 
promiscuous mode

Running 'ipsec statusall' confirms the Strongswan does not think the Child SA 
establishes.

Again, I know why the tunnel "fails" (and it does come up when I fix the 
configuration issue).  I just need some help understanding how\why either host 
fails to recover from the failed Child SA response.  Thanks for any help that 
can be provided.
_______________________________________________
Users mailing list
[email protected]
https://lists.strongswan.org/mailman/listinfo/users

Reply via email to