diff -Naur stunnel-5.30.orig/src/ctx.c stunnel-5.30/src/ctx.c
--- stunnel-5.30.orig/src/ctx.c	2016-01-15 16:45:23.000000000 +0000
+++ stunnel-5.30/src/ctx.c	2016-05-14 15:16:47.392859450 +0000
@@ -359,7 +359,7 @@
 /**************************************** initialize OpenSSL CONF */
 
 NOEXPORT int conf_init(SERVICE_OPTIONS *section) {
-#if OPENSSL_VERSION_NUMBER>=0x10002000L
+#if OPENSSL_VERSION_NUMBER>=0x10002000L && !defined(LIBRESSL_VERSION_NUMBER)
     SSL_CONF_CTX *cctx;
     NAME_LIST *curr;
     char *cmd, *param;
diff -Naur stunnel-5.30.orig/src/verify.c stunnel-5.30/src/verify.c
--- stunnel-5.30.orig/src/verify.c	2016-01-15 16:45:23.000000000 +0000
+++ stunnel-5.30/src/verify.c	2016-05-14 15:16:10.369860180 +0000
@@ -51,7 +51,7 @@
 NOEXPORT int verify_callback(int, X509_STORE_CTX *);
 NOEXPORT int verify_checks(CLI *, int, X509_STORE_CTX *);
 NOEXPORT int cert_check(CLI *, X509_STORE_CTX *, int);
-#if OPENSSL_VERSION_NUMBER>=0x10002000L
+#if OPENSSL_VERSION_NUMBER>=0x10002000L && !defined(LIBRESSL_VERSION_NUMBER)
 NOEXPORT int cert_check_subject(CLI *, X509_STORE_CTX *);
 #endif /* OPENSSL_VERSION_NUMBER>=0x10002000L */
 NOEXPORT int cert_check_local(X509_STORE_CTX *);
@@ -280,7 +280,7 @@
     }
 
     if(depth==0) { /* additional peer certificate checks */
-#if OPENSSL_VERSION_NUMBER>=0x10002000L
+#if OPENSSL_VERSION_NUMBER>=0x10002000L && !defined(LIBRESSL_VERSION_NUMBER)
         if(!cert_check_subject(c, callback_ctx))
             return 0; /* reject */
 #endif /* OPENSSL_VERSION_NUMBER>=0x10002000L */
@@ -291,7 +291,7 @@
     return 1; /* accept */
 }
 
-#if OPENSSL_VERSION_NUMBER>=0x10002000L
+#if OPENSSL_VERSION_NUMBER>=0x10002000L && !defined(LIBRESSL_VERSION_NUMBER)
 NOEXPORT int cert_check_subject(CLI *c, X509_STORE_CTX *callback_ctx) {
     X509 *cert=X509_STORE_CTX_get_current_cert(callback_ctx);
     NAME_LIST *ptr;
diff --git a/src/common.h b/src/common.h
index 93f165e..491d9de 100644
--- a/src/common.h
+++ b/src/common.h
@@ -448,7 +448,7 @@ extern char *sys_errlist[];
 #define OPENSSL_NO_TLS1_2
 #endif /* OpenSSL older than 1.0.1 || defined(OPENSSL_NO_TLS1) */
 
-#if OPENSSL_VERSION_NUMBER>=0x10100000L
+#if OPENSSL_VERSION_NUMBER>=0x10100000L && !defined(LIBRESSL_VERSION_NUMBER)
 #ifndef OPENSSL_NO_SSL2
 #define OPENSSL_NO_SSL2
 #endif /* !defined(OPENSSL_NO_SSL2) */
@@ -474,7 +474,7 @@ extern char *sys_errlist[];
 #include <openssl/des.h>
 #ifndef OPENSSL_NO_DH
 #include <openssl/dh.h>
-#if OPENSSL_VERSION_NUMBER<0x10100000L
+#if OPENSSL_VERSION_NUMBER<0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
 int DH_set0_pqg(DH *dh, BIGNUM *p, BIGNUM *q, BIGNUM *g);
 #endif /* OpenSSL older than 1.1.0 */
 #endif /* !defined(OPENSSL_NO_DH) */
diff --git a/src/prototypes.h b/src/prototypes.h
index 303ff77..ae22598 100644
--- a/src/prototypes.h
+++ b/src/prototypes.h
@@ -664,13 +664,13 @@ typedef enum {
 #endif /* OPENSSL_NO_DH */
     STUNNEL_LOCKS                           /* number of locks */
 } LOCK_TYPE;
-#if OPENSSL_VERSION_NUMBER < 0x10100004L
+#if OPENSSL_VERSION_NUMBER < 0x10100004L || defined(LIBRESSL_VERSION_NUMBER)
 typedef int STUNNEL_RWLOCK;
 #else
 typedef CRYPTO_RWLOCK *STUNNEL_RWLOCK;
 #endif
 extern STUNNEL_RWLOCK stunnel_locks[STUNNEL_LOCKS];
-#if OPENSSL_VERSION_NUMBER>=0x10100004L
+#if OPENSSL_VERSION_NUMBER>=0x10100004L && !defined(LIBRESSL_VERSION_NUMBER)
 #define CRYPTO_THREAD_read_unlock(type) CRYPTO_THREAD_unlock(type)
 #define CRYPTO_THREAD_write_unlock(type) CRYPTO_THREAD_unlock(type)
 #else
diff --git a/src/ssl.c b/src/ssl.c
index a7af7e6..1483734 100644
--- a/src/ssl.c
+++ b/src/ssl.c
@@ -50,7 +50,7 @@ NOEXPORT int add_rand_file(GLOBAL_OPTIONS *, const char *);
 int index_cli, index_opt, index_redirect, index_addr;
 
 int ssl_init(void) { /* init TLS before parsing configuration file */
-#if OPENSSL_VERSION_NUMBER>=0x10100000L
+#if OPENSSL_VERSION_NUMBER>=0x10100000L && !defined(LIBRESSL_VERSION_NUMBER)
     OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS |
         OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL);
 #else
@@ -83,7 +83,7 @@ int ssl_init(void) { /* init TLS before parsing configuration file */
 }
 
 #ifndef OPENSSL_NO_DH
-#if OPENSSL_VERSION_NUMBER<0x10100000L
+#if OPENSSL_VERSION_NUMBER<0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
 /* this is needed for dhparam.c generated with OpenSSL >= 1.1.0
  * to be linked against the older versions */
 int DH_set0_pqg(DH *dh, BIGNUM *p, BIGNUM *q, BIGNUM *g) {
diff --git a/src/sthreads.c b/src/sthreads.c
index 59c24a2..04fb256 100644
--- a/src/sthreads.c
+++ b/src/sthreads.c
@@ -47,7 +47,7 @@
 STUNNEL_RWLOCK stunnel_locks[STUNNEL_LOCKS];
 #endif
 
-#if OPENSSL_VERSION_NUMBER<0x10100004L
+#if OPENSSL_VERSION_NUMBER<0x10100004L || defined(LIBRESSL_VERSION_NUMBER)
 #define CRYPTO_THREAD_lock_new() CRYPTO_get_new_dynlockid()
 #endif
 
diff --git a/src/verify.c b/src/verify.c
index ac1c3ee..3e3bda4 100644
--- a/src/verify.c
+++ b/src/verify.c
@@ -348,7 +348,7 @@ NOEXPORT int cert_check_local(X509_STORE_CTX *callback_ctx) {
     cert=X509_STORE_CTX_get_current_cert(callback_ctx);
     subject=X509_get_subject_name(cert);
 
-#if OPENSSL_VERSION_NUMBER>=0x10000000L
+#if OPENSSL_VERSION_NUMBER>=0x10000000L && !defined(LIBRESSL_VERSION_NUMBER)
 #if OPENSSL_VERSION_NUMBER<0x10100006L
 #define X509_STORE_CTX_get1_certs X509_STORE_get1_certs
 #endif