When using keyed checksum types with TGS subkeys, Microsoft AD 2003

verifies the checksum using the subkey, whereas MIT and Heimdal verify
it using the TGS session key.  (RFC 4120 is actually silent on which
is correct; RFC 4757 specifies the TGS session key.)  To sidestep this
interop issue, don't use keyed checksum types with RC4 keys without
explicit configuration in krb5.conf.  Using keyed checksum types with
AES is fine since, experimentally, AD 2008 accepts checksums keyed
with the TGS session key.

ticket: 6490
status: open
tags: pullup

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@22356 dc483132-0cff-0310-8789-dd5450dbe970

diff --git a/src/lib/krb5/krb/send_tgs.c b/src/lib/krb5/krb/send_tgs.c
index 73980f2cf4121a7ad6016ae904ea57cb86f6816f..97cd02bf75e22d1dce73a3264075d9e506462d74 100644 (file)
--- a/src/lib/krb5/krb/send_tgs.c
+++ b/src/lib/krb5/krb/send_tgs.c
@@ -68,6 +68,8 @@ tgs_construct_tgsreq(krb5_context context, krb5_data *in_data,
     case ENCTYPE_DES_CBC_CRC:
     case ENCTYPE_DES_CBC_MD4:
     case ENCTYPE_DES_CBC_MD5:
+    case ENCTYPE_ARCFOUR_HMAC:
+    case ENCTYPE_ARCFOUR_HMAC_EXP:
        cksumtype = context->kdc_req_sumtype;
        break;
     default: