openssl: assume engine support in 1.0.0 or later

Commit 38203f1585da changed engine detection to be version-based,
with a baseline of openssl 1.0.1. This does in fact break builds
with openssl 1.0.0, which has engine support - the configure script
detects that ENGINE_cleanup() is available - but <openssl/engine.h>
doesn't get included to declare it.

According to upstream documentation, engine support was added to
mainstream openssl builds as of version 0.9.7:
https://github.com/openssl/openssl/blob/master/README.ENGINE

This commit drops the version test down to 1.0.0 as version 1.0.0d
is the oldest version I have to test with.

Closes #2732

diff --git a/lib/vtls/openssl.c b/lib/vtls/openssl.c
index 0b1929bd7e5cec05ce5c9f787384156eaafdada6..d5b474771e79aa88d380a8a3f1d5aed9978ac0f4 100644 (file)
--- a/lib/vtls/openssl.c
+++ b/lib/vtls/openssl.c
@@ -69,7 +69,7 @@
 #include <openssl/ocsp.h>
 #endif
 
-#if (OPENSSL_VERSION_NUMBER >= 0x10001000L) && /* 1.0.1 or later */     \
+#if (OPENSSL_VERSION_NUMBER >= 0x10000000L) && /* 1.0.0 or later */     \
   !defined(OPENSSL_NO_ENGINE)
 #define USE_OPENSSL_ENGINE
 #include <openssl/engine.h>