Parse the early_data extension

We also skip any early_data that subsequently gets sent. Later commits will
process it if we can.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2737)

1 files changed, 12 insertions, 0 deletions

diff --git a/ssl/statem/statem.c b/ssl/statem/statem.c
index 10d794ede7..9ec8e85426 100644
--- a/ssl/statem/statem.c
+++ b/ssl/statem/statem.c
@@ -151,6 +151,18 @@ void ossl_statem_set_in_handshake(SSL *s, int inhand)
         s->statem.in_handshake--;
 }
 
+/* Are we in a sensible state to skip over unreadable early data? */
+int ossl_statem_skip_early_data(SSL *s)
+{
+    if (!s->ext.expect_early_data)
+        return 0;
+
+    if (s->statem.hand_state != TLS_ST_SW_FINISHED)
+        return 0;
+
+    return 1;
+}
+
 void ossl_statem_set_hello_verify_done(SSL *s)
 {
     s->statem.state = MSG_FLOW_UNINITED;