9642 PKCS#11 softtoken should use explicit_bzero
Reviewed by: Dan McDonald <danmcd@joyent.com>
Reviewed by: Alex Wilson <alex.wilson@joyent.com>

@@ -19,10 +19,11 @@
  * CDDL HEADER END
  */
 
 /*
  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, Joyent, Inc.
  */
 
 #include <pthread.h>
 #include <stdlib.h>
 #include <string.h>

@@ -446,18 +447,13 @@
          * operation will be terminated so we need to do some cleanup.
          */
 cleanup:
         (void) pthread_mutex_lock(&session_p->session_mutex);
         des_ctx = (des_ctx_t *)soft_des_ctx->des_cbc;
-        if (des_ctx != NULL) {
-                bzero(des_ctx->dc_keysched, des_ctx->dc_keysched_len);
-                free(soft_des_ctx->des_cbc);
-        }
-
-        bzero(soft_des_ctx->key_sched, soft_des_ctx->keysched_len);
-        free(soft_des_ctx->key_sched);
-        free(session_p->encrypt.context);
+        free(des_ctx);
+        freezero(soft_des_ctx->key_sched, soft_des_ctx->keysched_len);
+        freezero(session_p->encrypt.context, sizeof (soft_des_ctx_t));
         session_p->encrypt.context = NULL;
         (void) pthread_mutex_unlock(&session_p->session_mutex);
 
         return (rv);
 }

@@ -775,19 +771,13 @@
          * operation will be terminated so we need to do some cleanup.
          */
 cleanup:
         (void) pthread_mutex_lock(&session_p->session_mutex);
         des_ctx = (des_ctx_t *)soft_des_ctx->des_cbc;
-        if (des_ctx != NULL) {
-                bzero(des_ctx->dc_keysched, des_ctx->dc_keysched_len);
-                free(soft_des_ctx->des_cbc);
-        }
-
-        bzero(soft_des_ctx->key_sched, soft_des_ctx->keysched_len);
-        free(soft_des_ctx->key_sched);
-        free(session_p->decrypt.context);
-        session_p->decrypt.context = NULL;
+        free(des_ctx);
+        freezero(soft_des_ctx->key_sched, soft_des_ctx->keysched_len);
+        freezero(session_p->decrypt.context, sizeof (soft_des_ctx_t));
         (void) pthread_mutex_unlock(&session_p->session_mutex);
 
         return (rv);
 }