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

@@ -20,10 +20,11 @@
  */
 
 /*
  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
+ * Copyright (c) 2018, Joyent, Inc.
  */
 
 #include <pthread.h>
 #include <stdlib.h>
 #include <string.h>

@@ -486,18 +487,25 @@
          * operation will be terminated so we need to do some cleanup.
          */
 cleanup:
         (void) pthread_mutex_lock(&session_p->session_mutex);
         aes_ctx = (aes_ctx_t *)soft_aes_ctx->aes_cbc;
-        if (aes_ctx != NULL) {
-                bzero(aes_ctx->ac_keysched, aes_ctx->ac_keysched_len);
-                free(soft_aes_ctx->aes_cbc);
+        switch (mechanism) {
+        case CKM_AES_ECB:
+                freezero(aes_ctx, sizeof (ecb_ctx_t));
+                break;
+        case CKM_AES_CMAC:
+        case CKM_AES_CBC:
+        case CKM_AES_CBC_PAD:
+                freezero(aes_ctx, sizeof (cbc_ctx_t));
+                break;
+        case CKM_AES_CTR:
+                freezero(aes_ctx, sizeof (ctr_ctx_t));
+                break;
         }
-
-        bzero(soft_aes_ctx->key_sched, soft_aes_ctx->keysched_len);
-        free(soft_aes_ctx->key_sched);
-        free(session_p->encrypt.context);
+        freezero(soft_aes_ctx->key_sched, soft_aes_ctx->keysched_len);
+        freezero(session_p->encrypt.context, sizeof (soft_aes_ctx_t));
         session_p->encrypt.context = NULL;
         (void) pthread_mutex_unlock(&session_p->session_mutex);
 
         return (rv);
 }

@@ -849,18 +857,13 @@
          * operation will be terminated so we need to do some cleanup.
          */
 cleanup:
         (void) pthread_mutex_lock(&session_p->session_mutex);
         aes_ctx = (aes_ctx_t *)soft_aes_ctx->aes_cbc;
-        if (aes_ctx != NULL) {
-                bzero(aes_ctx->ac_keysched, aes_ctx->ac_keysched_len);
-                free(soft_aes_ctx->aes_cbc);
-        }
-
-        bzero(soft_aes_ctx->key_sched, soft_aes_ctx->keysched_len);
-        free(soft_aes_ctx->key_sched);
-        free(session_p->decrypt.context);
+        free(aes_ctx);
+        freezero(soft_aes_ctx->key_sched, soft_aes_ctx->keysched_len);
+        freezero(session_p->decrypt.context, sizeof (soft_aes_ctx_t));
         session_p->decrypt.context = NULL;
         (void) pthread_mutex_unlock(&session_p->session_mutex);
 
         return (rv);
 }