krb5 commit: Don't reopen the KDB in update_princ_encryption

[Greg Hudson]

https://github.com/krb5/krb5/commit/1c65092f874edc41c02f328608e2e44a93a6fb89
commit 1c65092f874edc41c02f328608e2e44a93a6fb89
Author: Greg Hudson <ghudson at mit.edu>
Date:   Wed Jul 31 18:49:13 2013 -0400

    Don't reopen the KDB in update_princ_encryption
    
    kdb5_util update_princ_encryption iterates over the KDB and writes
    modified entries.  With the DB2 back end, the first write operation
    has to upgrade the lock and reopen the DB, which resets the cursor
    state.  Take out an explicit write lock before iterating to avoid this
    step.
    
    ticket: 7684 (new)

 src/kadmin/dbutil/kdb5_mkey.c |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/src/kadmin/dbutil/kdb5_mkey.c b/src/kadmin/dbutil/kdb5_mkey.c
index 4edacb6..0fbbb78 100644
--- a/src/kadmin/dbutil/kdb5_mkey.c
+++ b/src/kadmin/dbutil/kdb5_mkey.c
@@ -1050,6 +1050,16 @@ kdb5_update_princ_encryption(int argc, char *argv[])
         }
     }
 
+    if (!data.dry_run) {
+        /* Grab a write lock so we don't have to upgrade to a write lock and
+         * reopen the DB while iterating. */
+        retval = krb5_db_lock(util_context, KRB5_DB_LOCKMODE_EXCLUSIVE);
+        if (retval != 0 && retval != KRB5_PLUGIN_OP_NOTSUPP) {
+            com_err(progname, retval, _("trying to lock database"));
+            exit_status++;
+        }
+    }
+
     retval = krb5_db_iterate(util_context, name_pattern,
                              update_princ_encryption_1, &data);
     /* If exit_status is set, then update_princ_encryption_1 already
@@ -1058,6 +1068,8 @@ kdb5_update_princ_encryption(int argc, char *argv[])
         com_err(progname, retval, _("trying to process principal database"));
         exit_status++;
     }
+    if (!data.dry_run)
+        (void)krb5_db_unlock(util_context);
     (void) krb5_db_fini(util_context);
     if (data.dry_run) {
         printf(_("%u principals processed: %u would be updated, %u already "