From: Greg Hudson <ghudson@mit.edu>
Date: Tue, 29 Aug 2017 15:19:36 +0000 (-0400)
Subject: Don't set ctime in KDC error replies
X-Git-Tag: krb5-1.16-beta1~20
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=aff489766e8541bee59d0aa7b9cc7e62f5ca8232;p=thirdparty%2Fkrb5.git

Don't set ctime in KDC error replies

Setting the error ctime field to the client nonce assumes that the
client used its system time as the nonce, which is not recommended by
RFC 1510 and is prohibited by RFC 4120.  Omit the field instead, by
setting the structure field to 0.

ticket: 8610 (new)
---

diff --git a/src/kdc/do_as_req.c b/src/kdc/do_as_req.c
index 8cfb4ef82f..7c8da63e18 100644
--- a/src/kdc/do_as_req.c
+++ b/src/kdc/do_as_req.c
@@ -840,7 +840,7 @@ prepare_error_as(struct kdc_request_state *rstate, krb5_kdc_req *request,
         e_data[count] = cookie;
     }
 
-    errpkt.ctime = request->nonce;
+    errpkt.ctime = 0;
     errpkt.cusec = 0;
 
     retval = krb5_us_timeofday(kdc_context, &errpkt.stime, &errpkt.susec);
diff --git a/src/kdc/do_tgs_req.c b/src/kdc/do_tgs_req.c
index b9b1073fd4..cc5a692362 100644
--- a/src/kdc/do_tgs_req.c
+++ b/src/kdc/do_tgs_req.c
@@ -896,7 +896,7 @@ prepare_error_tgs (struct kdc_request_state *state,
     kdc_realm_t *kdc_active_realm = state->realm_data;
 
     errpkt.magic = KV5M_ERROR;
-    errpkt.ctime = request->nonce;
+    errpkt.ctime = 0;
     errpkt.cusec = 0;
 
     if ((retval = krb5_us_timeofday(kdc_context, &errpkt.stime,