diff --git a/lib/curl_endian.c b/lib/curl_endian.c
index 76deca6aa..c2d21de5e 100644
--- a/lib/curl_endian.c
+++ b/lib/curl_endian.c
@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -37,7 +37,7 @@
  *
  * Returns the integer.
  */
-unsigned short Curl_read16_le(unsigned char *buf)
+unsigned short Curl_read16_le(const unsigned char *buf)
 {
   return (unsigned short)(((unsigned short)buf[0]) |
                           ((unsigned short)buf[1] << 8));
@@ -56,7 +56,7 @@ unsigned short Curl_read16_le(unsigned char *buf)
  *
  * Returns the integer.
  */
-unsigned int Curl_read32_le(unsigned char *buf)
+unsigned int Curl_read32_le(const unsigned char *buf)
 {
   return ((unsigned int)buf[0]) | ((unsigned int)buf[1] << 8) |
          ((unsigned int)buf[2] << 16) | ((unsigned int)buf[3] << 24);
@@ -77,7 +77,7 @@ unsigned int Curl_read32_le(unsigned char *buf)
  * Returns the integer.
  */
 #if defined(HAVE_LONGLONG)
-unsigned long long Curl_read64_le(unsigned char *buf)
+unsigned long long Curl_read64_le(const unsigned char *buf)
 {
   return ((unsigned long long)buf[0]) |
          ((unsigned long long)buf[1] << 8) |
@@ -89,7 +89,7 @@ unsigned long long Curl_read64_le(unsigned char *buf)
          ((unsigned long long)buf[7] << 56);
 }
 #else
-unsigned __int64 Curl_read64_le(unsigned char *buf)
+unsigned __int64 Curl_read64_le(const unsigned char *buf)
 {
   return ((unsigned __int64)buf[0]) | ((unsigned __int64)buf[1] << 8) |
          ((unsigned __int64)buf[2] << 16) | ((unsigned __int64)buf[3] << 24) |
@@ -113,7 +113,7 @@ unsigned __int64 Curl_read64_le(unsigned char *buf)
  *
  * Returns the integer.
  */
-unsigned short Curl_read16_be(unsigned char *buf)
+unsigned short Curl_read16_be(const unsigned char *buf)
 {
   return (unsigned short)(((unsigned short)buf[0] << 8) |
                           ((unsigned short)buf[1]));
@@ -132,7 +132,7 @@ unsigned short Curl_read16_be(unsigned char *buf)
  *
  * Returns the integer.
  */
-unsigned int Curl_read32_be(unsigned char *buf)
+unsigned int Curl_read32_be(const unsigned char *buf)
 {
   return ((unsigned int)buf[0] << 24) | ((unsigned int)buf[1] << 16) |
          ((unsigned int)buf[2] << 8) | ((unsigned int)buf[3]);
@@ -153,7 +153,7 @@ unsigned int Curl_read32_be(unsigned char *buf)
  * Returns the integer.
  */
 #if defined(HAVE_LONGLONG)
-unsigned long long Curl_read64_be(unsigned char *buf)
+unsigned long long Curl_read64_be(const unsigned char *buf)
 {
   return ((unsigned long long)buf[0] << 56) |
          ((unsigned long long)buf[1] << 48) |
@@ -165,7 +165,7 @@ unsigned long long Curl_read64_be(unsigned char *buf)
          ((unsigned long long)buf[7]);
 }
 #else
-unsigned __int64 Curl_read64_be(unsigned char *buf)
+unsigned __int64 Curl_read64_be(const unsigned char *buf)
 {
   return ((unsigned __int64)buf[0] << 56) | ((unsigned __int64)buf[1] << 48) |
          ((unsigned __int64)buf[2] << 40) | ((unsigned __int64)buf[3] << 32) |
diff --git a/lib/curl_endian.h b/lib/curl_endian.h
index df8398c8c..8a2b07ad8 100644
--- a/lib/curl_endian.h
+++ b/lib/curl_endian.h
@@ -7,7 +7,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -23,32 +23,32 @@
  ***************************************************************************/
 
 /* Converts a 16-bit integer from little endian */
-unsigned short Curl_read16_le(unsigned char *buf);
+unsigned short Curl_read16_le(const unsigned char *buf);
 
 /* Converts a 32-bit integer from little endian */
-unsigned int Curl_read32_le(unsigned char *buf);
+unsigned int Curl_read32_le(const unsigned char *buf);
 
 #if (CURL_SIZEOF_CURL_OFF_T > 4)
 /* Converts a 64-bit integer from little endian */
 #if defined(HAVE_LONGLONG)
-unsigned long long Curl_read64_le(unsigned char *buf);
+unsigned long long Curl_read64_le(const unsigned char *buf);
 #else
-unsigned __int64 Curl_read64_le(unsigned char *buf);
+unsigned __int64 Curl_read64_le(const unsigned char *buf);
 #endif
 #endif
 
 /* Converts a 16-bit integer from big endian */
-unsigned short Curl_read16_be(unsigned char *buf);
+unsigned short Curl_read16_be(const unsigned char *buf);
 
 /* Converts a 32-bit integer from big endian */
-unsigned int Curl_read32_be(unsigned char *buf);
+unsigned int Curl_read32_be(const unsigned char *buf);
 
 #if (CURL_SIZEOF_CURL_OFF_T > 4)
 /* Converts a 64-bit integer from big endian */
 #if defined(HAVE_LONGLONG)
-unsigned long long Curl_read64_be(unsigned char *buf);
+unsigned long long Curl_read64_be(const unsigned char *buf);
 #else
-unsigned __int64 Curl_read64_be(unsigned char *buf);
+unsigned __int64 Curl_read64_be(const unsigned char *buf);
 #endif
 #endif
 
diff --git a/lib/smb.c b/lib/smb.c
index 7cb0c9611..f197fe1c0 100644
--- a/lib/smb.c
+++ b/lib/smb.c
@@ -6,7 +6,7 @@
  *                             \___|\___/|_| \_\_____|
  *
  * Copyright (C) 2014, Bill Nagel <wnagel@tycoint.com>, Exacq Technologies
- * Copyright (C) 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 2016, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -308,8 +308,8 @@ static CURLcode smb_recv_message(struct connectdata *conn, void **msg)
   if(smbc->got < sizeof(unsigned int))
     return CURLE_OK;
 
-  nbt_size = Curl_read16_be((unsigned char *)(buf + sizeof(unsigned short))) +
-             sizeof(unsigned int);
+  nbt_size = Curl_read16_be((const unsigned char *)(buf +
+             sizeof(unsigned short))) + sizeof(unsigned int);
   if(smbc->got < nbt_size)
     return CURLE_OK;
 
@@ -320,7 +320,7 @@ static CURLcode smb_recv_message(struct connectdata *conn, void **msg)
     if(nbt_size >= msg_size + sizeof(unsigned short)) {
       /* Add the byte count */
       msg_size += sizeof(unsigned short) +
-                  Curl_read16_le((unsigned char *)&buf[msg_size]);
+                  Curl_read16_le((const unsigned char *)&buf[msg_size]);
       if(nbt_size < msg_size)
         return CURLE_READ_ERROR;
     }
@@ -781,9 +781,9 @@ static CURLcode smb_request_state(struct connectdata *conn, bool *done)
       next_state = SMB_CLOSE;
       break;
     }
-    len = Curl_read16_le(((unsigned char *) msg) +
+    len = Curl_read16_le(((const unsigned char *) msg) +
                          sizeof(struct smb_header) + 11);
-    off = Curl_read16_le(((unsigned char *) msg) +
+    off = Curl_read16_le(((const unsigned char *) msg) +
                          sizeof(struct smb_header) + 13);
     if(len > 0) {
       if(off + sizeof(unsigned int) + len > smbc->got) {
@@ -812,7 +812,7 @@ static CURLcode smb_request_state(struct connectdata *conn, bool *done)
       next_state = SMB_CLOSE;
       break;
     }
-    len = Curl_read16_le(((unsigned char *) msg) +
+    len = Curl_read16_le(((const unsigned char *) msg) +
                          sizeof(struct smb_header) + 5);
     conn->data->req.bytecount += len;
     conn->data->req.offset += len;