diff --git a/src/util/sha256.cpp b/src/util/sha256.cpp
index 7aeea64..034d12e 100644
--- a/src/util/sha256.cpp
+++ b/src/util/sha256.cpp
@@ -82,14 +82,14 @@
   }
 
   // constant-time buffer comparison to mitigate timing attacks
-  return CRYPTO_memcmp(lhs.get(), rhs.get(), lhs.size()) == 0;
+  return CRYPTO_memcmp(lhs.data(), rhs.data(), lhs.size()) == 0;
 }
 
 Sha256&
 Sha256::operator<<(Sha256& src)
 {
   auto buf = src.computeDigest();
-  update(buf->get(), buf->size());
+  update(buf->data(), buf->size());
   return *this;
 }
 
diff --git a/src/util/string-helper.cpp b/src/util/string-helper.cpp
index 7665afc..8be94d0 100644
--- a/src/util/string-helper.cpp
+++ b/src/util/string-helper.cpp
@@ -1,5 +1,5 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
+/*
  * Copyright (c) 2013-2017 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
@@ -60,7 +60,7 @@
 void
 printHex(std::ostream& os, const Buffer& buffer, bool wantUpperCase)
 {
-  return printHex(os, buffer.buf(), buffer.size(), wantUpperCase);
+  return printHex(os, buffer.data(), buffer.size(), wantUpperCase);
 }
 
 std::string
@@ -74,7 +74,7 @@
 std::string
 toHex(const Buffer& buffer, bool wantUpperCase)
 {
-  return toHex(buffer.buf(), buffer.size(), wantUpperCase);
+  return toHex(buffer.data(), buffer.size(), wantUpperCase);
 }
 
 int