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<p class=MsoNormal>I am experiencing the following oddness I am hoping someone
can shed some light on...<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>We are using FR 2.X and LDAP for MSCHAPv2
authentication. We are storing the NT-Password Hash within LDAP,
utilizing ldap.attrmap to map our LDAP variable to "NT-Password" <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>So when an MSCHAPv2 based Auth comes in all is well, the
mschap module sees mschap attributes, sets Auth to MSCHAP. rlm_ldap dives
into LDAP and locates and maps "NT-Password" properly.
All is well.... ALMOST...<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>For a few lucky accounts this process comes to a halt, upon
inspection we noticed that the NT-Password being copied by rlm_ldap was being
truncated <o:p></o:p></p>
<p class=MsoNormal>[From Debug output]<o:p></o:p></p>
<p class=MsoNormal>rlm_ldap: unicodePWD -> NT-Password == 0x6f183bc46904 <o:p></o:p></p>
<p class=MsoNormal>This is super short... Look at a successful auth<o:p></o:p></p>
<p class=MsoNormal>rlm_ldap: unicodePWD -> NT-Password == 0xb31b12345aca32aaa607430cb7acdcb1<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>It appears though that there may be a bug in the string copy
function of the rlm_ldap function (or whatever is responsible for copying the
attributes from LDAP to Server core for MSCHAP challenge compare) We
noticed the truncation upon "00" and "3d" in the
NT-Password hash (so if the has was abc12300 or
abc1233d all you would see is abc123)<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Your input is greatly appreciated.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thank you<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Larry<o:p></o:p></p>
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