OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

iscsi-target: Reject mutual authentication with reflected CHAP_C 

commit 1d2b60a554 upstream.

This patch adds an explicit check in chap_server_compute_md5() to ensure
the CHAP_C value received from the initiator during mutual authentication
does not match the original CHAP_C provided by the target.

This is in line with RFC-3720, section 8.2.1:

   Originators MUST NOT reuse the CHAP challenge sent by the Responder
   for the other direction of a bidirectional authentication.
   Responders MUST check for this condition and close the iSCSI TCP
   connection if it occurs.

Reported-by: Tejas Vaykole <tejas.vaykole@calsoftinc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Nicholas Bellinger 2014-06-05 18:08:57 -07:00 committed by Greg Kroah-Hartman
parent 4b71e348b5
commit 124067ae66
1 changed files with 10 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
drivers/target/iscsi/iscsi_target_auth.c
View File

@ -313,6 +313,16 @@ static int chap_server_compute_md5(
pr_err("Unable to convert incoming challenge\n");
goto out;
}
/*
* During mutual authentication, the CHAP_C generated by the
* initiator must not match the original CHAP_C generated by
* the target.
*/
if (!memcmp(challenge_binhex, chap->challenge, CHAP_CHALLENGE_LENGTH)) {
pr_err("initiator CHAP_C matches target CHAP_C, failing"
" login attempt\n");
goto out;
}
/*
* Generate CHAP_N and CHAP_R for mutual authentication.
*/