Fix LibreSSL compatibility, patches from OpenBSD

http://cvsweb.openbsd.org/cgi-bin/cvsweb/ports/net/isc-bind/patches/

http://cvsweb.openbsd.org/cgi-bin/cvsweb/~checkout~/ports/net/isc-bind/patches/patch-lib_dns_dst_openssl_h?rev=1.1&content-type=text/plain
http://cvsweb.openbsd.org/cgi-bin/cvsweb/~checkout~/ports/net/isc-bind/patches/patch-lib_dns_openssl_link_c?rev=1.1&content-type=text/plain
http://cvsweb.openbsd.org/cgi-bin/cvsweb/~checkout~/ports/net/isc-bind/patches/patch-lib_dns_openssldh_link_c?rev=1.1&content-type=text/plain
http://cvsweb.openbsd.org/cgi-bin/cvsweb/~checkout~/ports/net/isc-bind/patches/patch-lib_dns_openssldsa_link_c?rev=1.1&content-type=text/plain
http://cvsweb.openbsd.org/cgi-bin/cvsweb/~checkout~/ports/net/isc-bind/patches/patch-lib_dns_opensslrsa_link_c?rev=1.1&content-type=text/plain

--- lib/dns/dst_openssl.h.orig	Wed Sep 16 14:00:47 2015
+++ lib/dns/dst_openssl.h	Wed Sep 16 14:02:42 2015
@@ -36,7 +36,7 @@
 #define USE_ENGINE 1
 #endif
 
-#if OPENSSL_VERSION_NUMBER < 0x10100000L
+#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
 /*
  * These are new in OpenSSL 1.1.0.  BN_GENCB _cb needs to be declared in
  * the function like this before the BN_GENCB_new call:
--- lib/dns/openssl_link.c.orig	Wed Sep 16 14:01:23 2015
+++ lib/dns/openssl_link.c	Wed Sep 16 14:01:46 2015
@@ -88,7 +88,7 @@ entropy_getpseudo(unsigned char *buf, int num) {
 	return (result == ISC_R_SUCCESS ? 1 : -1);
 }
 
-#if OPENSSL_VERSION_NUMBER < 0x10100000L
+#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
 static void
 entropy_add(const void *buf, int num, double entropy) {
 	/*
@@ -121,7 +121,7 @@ lock_callback(int mode, int type, const char *file, in
 		UNLOCK(&locks[type]);
 }
 
-#if OPENSSL_VERSION_NUMBER < 0x10100000L
+#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
 static unsigned long
 id_callback(void) {
 	return ((unsigned long)isc_thread_self());
@@ -187,7 +187,7 @@ dst__openssl_init(const char *engine) {
 	if (result != ISC_R_SUCCESS)
 		goto cleanup_mutexalloc;
 	CRYPTO_set_locking_callback(lock_callback);
-#if OPENSSL_VERSION_NUMBER < 0x10100000L
+#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
 	CRYPTO_set_id_callback(id_callback);
 #endif
 
@@ -287,7 +287,7 @@ dst__openssl_destroy(void) {
 	CRYPTO_cleanup_all_ex_data();
 #endif
 	ERR_clear_error();
-#if OPENSSL_VERSION_NUMBER < 0x10100000L
+#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
 	ERR_remove_state(0);
 #endif
 	ERR_free_strings();
--- lib/dns/openssldh_link.c.orig	Wed Sep 16 14:01:23 2015
+++ lib/dns/openssldh_link.c	Wed Sep 16 14:02:06 2015
@@ -173,7 +173,7 @@ openssldh_generate(dst_key_t *key, int generator, void
 	DH *dh = NULL;
 #if OPENSSL_VERSION_NUMBER > 0x00908000L
 	BN_GENCB *cb;
-#if OPENSSL_VERSION_NUMBER < 0x10100000L
+#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
 	BN_GENCB _cb;
 #endif
 	union {
@@ -210,7 +210,7 @@ openssldh_generate(dst_key_t *key, int generator, void
 		if (dh == NULL)
 			return (dst__openssl_toresult(ISC_R_NOMEMORY));
 		cb = BN_GENCB_new();
-#if OPENSSL_VERSION_NUMBER >= 0x10100000L
+#if OPENSSL_VERSION_NUMBER >= 0x10100000L && !defined(LIBRESSL_VERSION_NUMBER)
 		if (cb == NULL) {
 			DH_free(dh);
 			return (dst__openssl_toresult(ISC_R_NOMEMORY));
--- lib/dns/openssldsa_link.c.orig	Wed Sep 16 14:01:23 2015
+++ lib/dns/openssldsa_link.c	Wed Sep 16 14:02:22 2015
@@ -359,7 +359,7 @@ openssldsa_generate(dst_key_t *key, int unused, void (
 	isc_result_t result;
 #if OPENSSL_VERSION_NUMBER > 0x00908000L
 	BN_GENCB *cb;
-#if OPENSSL_VERSION_NUMBER < 0x10100000L
+#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
 	BN_GENCB _cb;
 #endif
 	union {
@@ -383,7 +383,7 @@ openssldsa_generate(dst_key_t *key, int unused, void (
 	if (dsa == NULL)
 		return (dst__openssl_toresult(DST_R_OPENSSLFAILURE));
 	cb = BN_GENCB_new();
-#if OPENSSL_VERSION_NUMBER >= 0x10100000L
+#if OPENSSL_VERSION_NUMBER >= 0x10100000L && !defined(LIBRESSL_VERSION_NUMBER)
 	if (cb == NULL) {
 		DSA_free(dsa);
 		return (dst__openssl_toresult(DST_R_OPENSSLFAILURE));
--- lib/dns/opensslrsa_link.c.orig	Wed Sep 16 14:01:23 2015
+++ lib/dns/opensslrsa_link.c	Wed Sep 16 14:02:31 2015
@@ -771,7 +771,7 @@ opensslrsa_generate(dst_key_t *key, int exp, void (*ca
 	} u;
 	RSA *rsa = RSA_new();
 	BIGNUM *e = BN_new();
-#if OPENSSL_VERSION_NUMBER < 0x10100000L
+#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
 	BN_GENCB _cb;
 #endif
 	BN_GENCB *cb = BN_GENCB_new();