From adb4e41a1ab2202e48c5a4db465d67d8e32415c7 Mon Sep 17 00:00:00 2001
From: Alessandro Ghedini <alessandro@ghedini.me>
Date: Thu, 19 Feb 2015 19:41:48 +0100
Subject: [PATCH] polarssl: make it possible to enable ALPN/NPN without HTTP2

---
 lib/vtls/polarssl.c | 46 +++++++++++++++++++++++----------------------
 1 file changed, 24 insertions(+), 22 deletions(-)

diff --git a/lib/vtls/polarssl.c b/lib/vtls/polarssl.c
index 2d46aae76..b7f2f6c94 100644
--- a/lib/vtls/polarssl.c
+++ b/lib/vtls/polarssl.c
@@ -118,11 +118,8 @@ static void polarssl_debug(void *context, int level, const char *line)
 #endif
 
 /* ALPN for http2? */
-#ifdef USE_NGHTTP2
-#  undef HAS_ALPN
-#  ifdef POLARSSL_SSL_ALPN
-#    define HAS_ALPN
-#  endif
+#ifdef POLARSSL_SSL_ALPN
+#  define HAS_ALPN
 #endif
 
 static Curl_recv polarssl_recv;
@@ -357,16 +354,23 @@ polarssl_connect_step1(struct connectdata *conn,
   }
 
 #ifdef HAS_ALPN
-  if(data->set.httpversion == CURL_HTTP_VERSION_2_0) {
-    if(data->set.ssl_enable_alpn) {
-      static const char* protocols[] = {
-        NGHTTP2_PROTO_VERSION_ID, ALPN_HTTP_1_1, NULL
-      };
-      ssl_set_alpn_protocols(&connssl->ssl, protocols);
-      infof(data, "ALPN, offering %s, %s\n", protocols[0],
-            protocols[1]);
-      connssl->asked_for_h2 = TRUE;
+  if(data->set.ssl_enable_alpn) {
+    static const char* protocols[3];
+    int cur = 0;
+
+#ifdef USE_NGHTTP2
+    if(data->set.httpversion == CURL_HTTP_VERSION_2_0) {
+      protocols[cur++] = NGHTTP2_PROTO_VERSION_ID;
+      infof(data, "ALPN, offering %s\n", NGHTTP2_PROTO_VERSION_ID);
     }
+#endif
+
+    protocols[cur++] = ALPN_HTTP_1_1;
+    infof(data, "ALPN, offering %s\n", ALPN_HTTP_1_1);
+
+    protocols[cur] = NULL;
+
+    ssl_set_alpn_protocols(&connssl->ssl, protocols);
   }
 #endif
 
@@ -388,10 +392,6 @@ polarssl_connect_step2(struct connectdata *conn,
   struct ssl_connect_data* connssl = &conn->ssl[sockindex];
   char buffer[1024];
 
-#ifdef HAS_ALPN
-  const char* next_protocol;
-#endif
-
   char errorbuf[128];
   errorbuf[0] = 0;
 
@@ -461,22 +461,24 @@ polarssl_connect_step2(struct connectdata *conn,
 
 #ifdef HAS_ALPN
   if(data->set.ssl_enable_alpn) {
-    next_protocol = ssl_get_alpn_protocol(&connssl->ssl);
+    const char *next_protocol = ssl_get_alpn_protocol(&connssl->ssl);
 
     if(next_protocol != NULL) {
       infof(data, "ALPN, server accepted to use %s\n", next_protocol);
 
+#ifdef USE_NGHTTP2
       if(!strncmp(next_protocol, NGHTTP2_PROTO_VERSION_ID,
                   NGHTTP2_PROTO_VERSION_ID_LEN)) {
         conn->negnpn = NPN_HTTP2;
       }
-      else if(!strncmp(next_protocol, ALPN_HTTP_1_1, ALPN_HTTP_1_1_LENGTH)) {
+      else
+#endif
+      if(!strncmp(next_protocol, ALPN_HTTP_1_1, ALPN_HTTP_1_1_LENGTH)) {
         conn->negnpn = NPN_HTTP1_1;
       }
     }
-    else if(connssl->asked_for_h2) {
+    else
       infof(data, "ALPN, server did not agree to a protocol\n");
-    }
   }
 #endif