Detect CyaSSL SNI enabled on build time

* Build should not failed if no CyaSSL SNI enabled.

Author: neutronth

configure.in

@@ -94,6 +94,26 @@ if test "x$enable_cyassl" = xyes; then
         AC_SEARCH_LIBS([CyaSSLv23_client_method], [cyassl wolfssl], [], [
                 AC_MSG_ERROR([unable to find the CyaSSLv23_client_method function.])
         ])
+
+        AC_MSG_CHECKING([for the CyaSSL SNI enabled])
+        AC_LINK_IFELSE([AC_LANG_PROGRAM(
+        [[
+                #define HAVE_SNI
+                #include <cyassl/ssl.h>
+        ]], [[
+                CYASSL_CTX *ctx;
+                CyaSSL_Init();
+                ctx = CyaSSL_CTX_new(CyaTLSv1_client_method());
+                CyaSSL_CTX_UseSNI(ctx, CYASSL_SNI_HOST_NAME, "wifidog.org", 11);
+        ]])], [enabled_sni=yes], [enabled_sni=no])
+
+        if test "x$enabled_sni" = xyes; then
+                AC_MSG_RESULT([yes])
+                AC_DEFINE([HAVE_SNI],, "Compile with CyaSSL SNI support")
+        else
+                AC_MSG_RESULT([no])
+        fi
+
         AC_DEFINE(USE_CYASSL,, "Compile with CyaSSL support")
 fi
 ])

src/conf.c

@@ -803,6 +803,10 @@ config_read(const char *filename)
                     }
 #ifndef USE_CYASSL
                     debug(LOG_WARNING, "SSLUseSNI is set but no SSL compiled in. Ignoring!");
+#else
+#ifndef HAVE_SNI
+                    debug(LOG_WARNING, "SSLUseSNI is set but no CyaSSL SNI enabled. Ignoring!");
+#endif
 #endif
                     break;
                 case oBadOption:

src/simple_http.c

@@ -179,6 +179,7 @@ get_cyassl_ctx(const char *hostname)
             }
         }
 
+#ifdef HAVE_SNI
         if (config->ssl_use_sni) {
             debug(LOG_INFO, "Setting SSL using SNI for hostname %s",
                 hostname);
@@ -191,6 +192,7 @@ get_cyassl_ctx(const char *hostname)
                 return NULL;
             }
         }
+#endif
 
         if (config->ssl_verify) {
             /* Use trusted certs */