diff -urN old/src/dep/ntpengine/ntp_isc_md5.c new/src/dep/ntpengine/ntp_isc_md5.c
--- old/src/dep/ntpengine/ntp_isc_md5.c	2015-06-29 17:13:29.000000000 +0200
+++ new/src/dep/ntpengine/ntp_isc_md5.c	2018-09-15 22:56:18.469044902 +0200
@@ -262,7 +262,7 @@
 {
 	u_char	digest[64];
 	u_int	len;
-	EVP_MD_CTX ctx;
+	PTPD_EVP_MD_CTX ctx;
         pkt[length / 4] = htonl(keyid); 
 	EVP_DigestInit(&ctx);
 	EVP_DigestUpdate(&ctx, (u_char *)key, (u_int)strlen(key));
diff -urN old/src/dep/ntpengine/ntp_isc_md5.h new/src/dep/ntpengine/ntp_isc_md5.h
--- old/src/dep/ntpengine/ntp_isc_md5.h	2015-06-29 17:13:29.000000000 +0200
+++ new/src/dep/ntpengine/ntp_isc_md5.h	2018-09-15 22:56:11.852020732 +0200
@@ -80,7 +80,7 @@
 # define MD5Init(c)             isc_md5_init(c)
 # define MD5Update(c, p, s)     isc_md5_update(c, p, s)
 # define MD5Final(d, c)         isc_md5_final((c), (d)) /* swapped */
-  typedef MD5_CTX                       EVP_MD_CTX;
+  typedef MD5_CTX                       PTPD_EVP_MD_CTX;
 # define EVP_DigestInit(c)              MD5Init(c)
 # define EVP_DigestUpdate(c, p, s)      MD5Update(c, p, s)
 # define EVP_DigestFinal(c, d, pdl)     \