krb5 commit [krb5-1.16]: Expose context errors in pkinit_server_plugin_init

https://github.com/krb5/krb5/commit/96bbaedd6e665b67ef89452e3cc84bc36f7860dc
commit 96bbaedd6e665b67ef89452e3cc84bc36f7860dc
Author: Robbie Harwood <[email protected]>
Date:   Mon Nov 13 13:32:37 2017 -0500

    Expose context errors in pkinit_server_plugin_init
    
    Commit 3ff426b9048a8024e5c175256c63cd0ad0572320 attempted to display
    an error when OCSP support was requested, but this error message was
    suppressed in pkinit_server_plugin_init().  Add a trace log for each
    realm initialization error, and pass through the realm initialization
    error when the KDC serves only one realm.  Other error messages from
    pkinit_init_kdc_profile(), such as missing pkinit_identity or
    pkinit_anchors, are also now exposted.
    
    [[email protected]: clarified commit message]
    
    (cherry picked from commit 225aab3540c13c6289b22022d5e110f6fc26151d)
    
    ticket: 8621
    version_fixed: 1.16

 src/plugins/preauth/pkinit/pkinit_srv.c   |   19 +++++++++++++------
 src/plugins/preauth/pkinit/pkinit_trace.h |    3 +++
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/src/plugins/preauth/pkinit/pkinit_srv.c b/src/plugins/preauth/pkinit/pkinit_srv.c
index 7210fc1..4e96858 100644
--- a/src/plugins/preauth/pkinit/pkinit_srv.c
+++ b/src/plugins/preauth/pkinit/pkinit_srv.c
@@ -1680,16 +1680,23 @@ pkinit_server_plugin_init(krb5_context context,
 
     for (i = 0, j = 0; i < numrealms; i++) {
         TRACE_PKINIT_SERVER_INIT_REALM(context, realmnames[i]);
-        retval = pkinit_server_plugin_init_realm(context, realmnames[i], &plgctx);
-        if (retval == 0 && plgctx != NULL)
+        krb5_clear_error_message(context);
+        retval = pkinit_server_plugin_init_realm(context, realmnames[i],
+                                                 &plgctx);
+        if (retval)
+            TRACE_PKINIT_SERVER_INIT_FAIL(context, realmnames[i], retval);
+        else
             realm_contexts[j++] = plgctx;
     }
 
     if (j == 0) {
-        retval = EINVAL;
-        krb5_set_error_message(context, retval,
-                               _("No realms configured correctly for pkinit "
-                                 "support"));
+        if (numrealms == 1) {
+            k5_prependmsg(context, retval, "PKINIT initialization failed");
+        } else {
+            retval = EINVAL;
+            k5_setmsg(context, retval,
+                      _("No realms configured correctly for pkinit support"));
+        }
         goto errout;
     }
 
diff --git a/src/plugins/preauth/pkinit/pkinit_trace.h b/src/plugins/preauth/pkinit/pkinit_trace.h
index acd485b..d4eb39d 100644
--- a/src/plugins/preauth/pkinit/pkinit_trace.h
+++ b/src/plugins/preauth/pkinit/pkinit_trace.h
@@ -102,6 +102,9 @@
     TRACE(c, "PKINIT server skipping EKU check due to configuration")
 #define TRACE_PKINIT_SERVER_INIT_REALM(c, realm)                \
     TRACE(c, "PKINIT server initializing realm {str}", realm)
+#define TRACE_PKINIT_SERVER_INIT_FAIL(c, realm, retval)                 \
+    TRACE(c, "PKINIT server initialization failed for realm {str}: {kerr}", \
+          realm, retval)
 #define TRACE_PKINIT_SERVER_MATCHING_UPN_FOUND(c)                       \
     TRACE(c, "PKINIT server found a matching UPN SAN in client cert")
 #define TRACE_PKINIT_SERVER_MATCHING_SAN_FOUND(c)                       \