fixed issue where go/C pointer sharing rules were being violated (go 1.6+).

Author: jb0n

Diff for: ctx.go

@@ -74,23 +74,23 @@ static long SSL_CTX_set_tlsext_servername_callback_not_a_macro(SSL_CTX* ctx, voi
     return SSL_CTX_set_tlsext_servername_callback(ctx, fp);
 }
 
-typedef struct TlsServernameData {
+typedef struct TlsExtData {
     void *go_ctx;
     SSL_CTX *ctx;
     void *arg;
-} TlsServernameData;
+} TlsExtData;
 
-extern int callServerNameCb(SSL* ssl, int ad, void* arg);
+extern int callServernameCb(SSL* ssl, int ad, void* arg);
 
 static int call_go_servername(SSL* ssl, int ad, void* arg) {
-    return callServerNameCb(ssl, ad, arg);
+    return callServernameCb(ssl, ad, arg);
 }
 
-static int servername_gateway(TlsServernameData* cw) {
+static int servername_gateway(TlsExtData* cw) {
     SSL_CTX* ctx = cw->ctx;
     //TODO: figure out what to do with return codes. The first isn't 0
     SSL_CTX_set_tlsext_servername_callback(ctx, call_go_servername);
-    SSL_CTX_set_tlsext_servername_arg(ctx, cw);
+    SSL_CTX_set_tlsext_servername_arg(ctx, cw.arg);
     return 0;
 }
 
@@ -141,13 +141,13 @@ var (
 )
 
 type Ctx struct {
-	ctx           *C.SSL_CTX
-	cert          *Certificate
-	chain         []*Certificate
-	key           PrivateKey
-	verify_cb     VerifyCallback
-	servername_cb ServerNameCallback
-	ted           C.TlsServernameData
+	ctx       *C.SSL_CTX
+	cert      *Certificate
+	chain     []*Certificate
+	key       PrivateKey
+	verify_cb VerifyCallback
+	//servername_cb ServerNameCallback
+	servername_cb func(ssl Conn, ad int, arg unsafe.Pointer) int
 }
 
 //export get_ssl_ctx_idx
@@ -634,11 +634,11 @@ func (c *Ctx) SessGetCacheSize() int {
 
 // Set SSL_CTX_set_tlsext_servername_callback
 // https://www.openssl.org/docs/manmaster/ssl/???
-type ServerNameCallback func(ssl Conn, ad int, arg unsafe.Pointer) int
+//type ServerNameCallback func(ssl *C.SSL, ad C.int, arg unsafe.Pointer) int
 
-//export callServerNameCb
-func callServerNameCb(ssl *C.SSL, ad C.int, arg unsafe.Pointer) C.int {
-	var ted *C.TlsServernameData = (*C.TlsServernameData)(arg)
+//export callServernameCb
+func callServernameCb(ssl *C.SSL, ad C.int, arg unsafe.Pointer) C.int {
+	var ted *C.TlsExtData = (*C.TlsExtData)(arg)
 	goCtx := (*Ctx)(ted.go_ctx)
 
 	//setup a dummy Conn so we can associate a SSL_CTX from user callback
@@ -650,13 +650,13 @@ func callServerNameCb(ssl *C.SSL, ad C.int, arg unsafe.Pointer) C.int {
 	return C.int(ret)
 }
 
-func (c *Ctx) SetTlsExtServerNameCallback(cb func(ssl Conn, ad int, arg unsafe.Pointer) int,
-	arg unsafe.Pointer) int {
+//func (c *Ctx) SetTlsExtServerNameCallback(cb ServerNameCallback) int {
+func (c *Ctx) SetTlsExtServerNameCallback(cb func(ssl Conn, ad int, arg unsafe.Pointer) int, arg unsafe.Pointer) int {
 	c.servername_cb = cb
-	c.ted = C.TlsServernameData{
+	cw := C.TlsExtData{
 		go_ctx: unsafe.Pointer(c),
 		ctx:    c.ctx,
 		arg:    arg,
 	}
-	return int(C.servername_gateway(&c.ted))
+	return int(C.servername_gateway(&cw))
 }