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

*** 19,28 ****
--- 19,29 ----
   * CDDL HEADER END
   */
  /*
   * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
+  * Copyright (c) 2018, Joyent, Inc.
   */
  
  #include <pthread.h>
  #include <stdlib.h>
  #include <string.h>
*** 820,849 ****
           * The final output of this process is the A buffer
           */
          (void) memcpy(keybuf, A, keysize);
  
  cleanup:
!         if (A) {
!                 bzero(A, Alen);
!                 free(A);
!         }
!         if (Ai) {
!                 bzero(Ai, AiLen);
!                 free(Ai);
!         }
!         if (B) {
!                 bzero(B, Blen);
!                 free(B);
!         }
!         if (D) {
!                 bzero(D, Dlen);
!                 free(D);
!         }
!         if (I) {
!                 bzero(I, Ilen);
!                 free(I);
!         }
          return (rv);
  }
  
  CK_RV
  soft_derivekey(soft_session_t *session_p, CK_MECHANISM_PTR pMechanism,
--- 821,835 ----
           * The final output of this process is the A buffer
           */
          (void) memcpy(keybuf, A, keysize);
  
  cleanup:
!         freezero(A, Alen);
!         freezero(Ai, AiLen);
!         freezero(B, Blen);
!         freezero(D, Dlen);
!         freezero(I, Ilen);
          return (rv);
  }
  
  CK_RV
  soft_derivekey(soft_session_t *session_p, CK_MECHANISM_PTR pMechanism,
*** 1398,1408 ****
                      ((i + 1) == blocks ? remainder : hLen));
  
                  keydata += hLen;
          }
          (void) soft_delete_object(session_p, hmac_key, B_FALSE, B_FALSE);
!         free(salt);
  
          return (rv);
  }
  
  CK_RV
--- 1384,1394 ----
                      ((i + 1) == blocks ? remainder : hLen));
  
                  keydata += hLen;
          }
          (void) soft_delete_object(session_p, hmac_key, B_FALSE, B_FALSE);
!         freezero(salt, params->ulSaltSourceDataLen);
  
          return (rv);
  }
  
  CK_RV
*** 1533,1550 ****
              pWrappedKey, pulWrappedKeyLen);
  
  cleanup_wrap:
          if (padded_data != NULL && padded_len != plain_len) {
                  /* Clear buffer before returning to memory pool. */
!                 (void) memset(padded_data, 0x0, padded_len);
!                 free(padded_data);
          }
  
          if ((hkey_p->class != CKO_SECRET_KEY) && (plain_data != NULL)) {
                  /* Clear buffer before returning to memory pool. */
!                 (void) memset(plain_data, 0x0, plain_len);
!                 free(plain_data);
          }
  
          return (rv);
  }
  
--- 1519,1534 ----
              pWrappedKey, pulWrappedKeyLen);
  
  cleanup_wrap:
          if (padded_data != NULL && padded_len != plain_len) {
                  /* Clear buffer before returning to memory pool. */
!                 freezero(padded_data, padded_len);
          }
  
          if ((hkey_p->class != CKO_SECRET_KEY) && (plain_data != NULL)) {
                  /* Clear buffer before returning to memory pool. */
!                 freezero(plain_data, plain_len);
          }
  
          return (rv);
  }
  
*** 1820,1831 ****
                          goto cleanup_unwrap;
          }
  
          if (new_objp->class != CKO_SECRET_KEY) {
                  /* Clear buffer before returning to memory pool. */
!                 (void) memset(plain_data, 0x0, plain_len);
!                 free(plain_data);
          }
  
          *phKey = (CK_OBJECT_HANDLE)new_objp;
  
          return (CKR_OK);
--- 1804,1814 ----
                          goto cleanup_unwrap;
          }
  
          if (new_objp->class != CKO_SECRET_KEY) {
                  /* Clear buffer before returning to memory pool. */
!                 freezero(plain_data, plain_len);
          }
  
          *phKey = (CK_OBJECT_HANDLE)new_objp;
  
          return (CKR_OK);
*** 1832,1843 ****
  
  cleanup_unwrap:
          /* The decrypted private key buffer must be freed explicitly. */
          if ((new_objp->class != CKO_SECRET_KEY) && (plain_data != NULL)) {
                  /* Clear buffer before returning to memory pool. */
!                 (void) memset(plain_data, 0x0, plain_len);
!                 free(plain_data);
          }
  
          /* sck and new_objp are indirectly free()d inside these functions */
          if (IS_TOKEN_OBJECT(new_objp))
                  soft_delete_token_object(new_objp, persistent, B_FALSE);
--- 1815,1825 ----
  
  cleanup_unwrap:
          /* The decrypted private key buffer must be freed explicitly. */
          if ((new_objp->class != CKO_SECRET_KEY) && (plain_data != NULL)) {
                  /* Clear buffer before returning to memory pool. */
!                 freezero(plain_data, plain_len);
          }
  
          /* sck and new_objp are indirectly free()d inside these functions */
          if (IS_TOKEN_OBJECT(new_objp))
                  soft_delete_token_object(new_objp, persistent, B_FALSE);