The main handshake loop can be shared between client and server.

Pull the shared code up into a function and call it from tls13_connect()
and tls13_accept() instead of duplicating it.

"Yes, please!" tb@

2 files changed, 15 insertions, 29 deletions

diff --git a/src/lib/libssl/tls13_handshake.c b/src/lib/libssl/tls13_handshake.c
index 92780bb2f2..9e17fd1351 100644
--- a/src/lib/libssl/tls13_handshake.c
+++ b/src/lib/libssl/tls13_handshake.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: tls13_handshake.c,v 1.15 2019/01/21 06:58:44 jsing Exp $      */
+/*      $OpenBSD: tls13_handshake.c,v 1.16 2019/01/21 10:44:08 jsing Exp $      */
 /*
  * Copyright (c) 2018-2019 Theo Buehler <tb@openbsd.org>
  * Copyright (c) 2019 Joel Sing <jsing@openbsd.org>
@@ -286,13 +286,11 @@ tls13_handshake_advance_state_machine(struct tls13_ctx *ctx)
 }
 
 int
-tls13_connect(struct tls13_ctx *ctx)
+tls13_handshake_perform(struct tls13_ctx *ctx)
 {
         struct tls13_handshake_action *action;
         int ret;
 
-        ctx->mode = TLS13_HS_CLIENT;
-
         for (;;) {
                 if ((action = tls13_handshake_active_action(ctx)) == NULL)
                         return TLS13_IO_FAILURE;
@@ -300,7 +298,7 @@ tls13_connect(struct tls13_ctx *ctx)
                 if (action->handshake_complete)
                         return TLS13_IO_SUCCESS;
 
-                if (action->sender == TLS13_HS_CLIENT) {
+                if (action->sender == ctx->mode) {
                         if ((ret = tls13_handshake_send_action(ctx, action)) <= 0)
                                 return ret;
                 } else {
@@ -314,33 +312,19 @@ tls13_connect(struct tls13_ctx *ctx)
 }
 
 int
-tls13_accept(struct tls13_ctx *ctx)
+tls13_connect(struct tls13_ctx *ctx)
 {
-        struct tls13_handshake_action *action;
-        int ret;
-
-        ctx->mode = TLS13_HS_SERVER;
-
-        for (;;) {
-                if ((action = tls13_handshake_active_action(ctx)) == NULL)
-                        return TLS13_IO_FAILURE;
-
-                if (action->handshake_complete)
-                        return TLS13_IO_SUCCESS;
+        ctx->mode = TLS13_HS_CLIENT;
 
-                if (action->sender == TLS13_HS_SERVER) {
-                        if ((ret = tls13_handshake_send_action(ctx, action)) <= 0)
-                                return ret;
-                } else {
-                        if ((ret = tls13_handshake_recv_action(ctx, action)) <= 0)
-                                return ret;
-                }
+        return tls13_handshake_perform(ctx);
+}
 
-                if (!tls13_handshake_advance_state_machine(ctx))
-                        return TLS13_IO_FAILURE;
-        }
+int
+tls13_accept(struct tls13_ctx *ctx)
+{
+        ctx->mode = TLS13_HS_SERVER;
 
-        return 1;
+        return tls13_handshake_perform(ctx);
 }
 
 int
diff --git a/src/lib/libssl/tls13_internal.h b/src/lib/libssl/tls13_internal.h
index 03fdab7e53..03de0fc40e 100644
--- a/src/lib/libssl/tls13_internal.h
+++ b/src/lib/libssl/tls13_internal.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: tls13_internal.h,v 1.12 2019/01/21 09:10:58 jsing Exp $ */
+/* $OpenBSD: tls13_internal.h,v 1.13 2019/01/21 10:44:08 jsing Exp $ */
 /*
  * Copyright (c) 2018 Bob Beck <beck@openbsd.org>
  * Copyright (c) 2018 Theo Buehler <tb@openbsd.org>
@@ -186,6 +186,8 @@ int tls13_legacy_write_bytes(SSL *ssl, int type, const void *buf, int len);
 #define TLS13_MT_KEY_UPDATE                     24
 #define TLS13_MT_MESSAGE_HASH                   254
 
+int tls13_handshake_perform(struct tls13_ctx *ctx);
+
 int tls13_client_hello_send(struct tls13_ctx *ctx);
 int tls13_client_hello_recv(struct tls13_ctx *ctx);
 int tls13_client_hello_retry_send(struct tls13_ctx *ctx);