[krb5] - fix reading of keyUsage extensions when attempting to select pkinit client certs (part of #629022,

[Nalin Dahyabhai]

commit 3fe7ccdb9298e5b6f9fa9dc25bef21c0715ece21
Author: Nalin Dahyabhai <nalin at redhat.com>
Date:   Thu Sep 16 19:31:54 2010 -0400

    - fix reading of keyUsage extensions when attempting to select pkinit client certs (part of #629022, RT#6775)

 krb5-trunk-key_usage.patch |   25 +++++++++++++++++++++++++
 1 files changed, 25 insertions(+), 0 deletions(-)
---
diff --git a/krb5-trunk-key_usage.patch b/krb5-trunk-key_usage.patch
new file mode 100644
index 0000000..f45db69
--- /dev/null
+++ b/krb5-trunk-key_usage.patch
@@ -0,0 +1,25 @@
+Reading the NID_key_usage extension doesn't ensure that the ex_flags and
+ex_kusage fields that the ku_reject() macro checks.  It'd probably be
+better to check the usage string directly, but calling X509_check_ca()
+makes the right things happen.  RT#6775, part of #629022.
+
+Index: src/plugins/preauth/pkinit/pkinit_crypto_openssl.c
+===================================================================
+--- src/plugins/preauth/pkinit/pkinit_crypto_openssl.c	(revision 24312)
++++ src/plugins/preauth/pkinit/pkinit_crypto_openssl.c	(revision 24313)
+@@ -2005,6 +2005,7 @@
+             pkiDebug("%s: found acceptable EKU, checking for digitalSignature\n", __FUNCTION__);
+ 
+             /* check that digitalSignature KeyUsage is present */
++            X509_check_ca(reqctx->received_cert);
+             if ((usage = X509_get_ext_d2i(reqctx->received_cert,
+                                           NID_key_usage, NULL, NULL))) {
+ 
+@@ -4551,6 +4552,7 @@
+     }
+ 
+     /* Make sure usage exists before checking bits */
++    X509_check_ca(x);
+     usage = X509_get_ext_d2i(x, NID_key_usage, NULL, NULL);
+     if (usage) {
+         if (!ku_reject(x, X509v3_KU_DIGITAL_SIGNATURE))