Move state machine knowledge out of the record layer
The record layer was making decisions that should really be left to the
state machine around unexpected handshake messages that are received after
the initial handshake (i.e. renegotiation related messages). This commit
removes that code from the record layer and updates the state machine
accordingly. This simplifies the state machine and paves the way for
handling other messages post-handshake such as the NewSessionTicket in
TLSv1.3.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2259)
diff --git a/ssl/s3_lib.c b/ssl/s3_lib.c
index ff4a03b..1655333 100644
--- a/ssl/s3_lib.c
+++ b/ssl/s3_lib.c
@@ -3822,7 +3822,7 @@
{
clear_sys_error();
if (s->s3->renegotiate)
- ssl3_renegotiate_check(s);
+ ssl3_renegotiate_check(s, 0);
return s->method->ssl_write_bytes(s, SSL3_RT_APPLICATION_DATA, buf, len,
written);
@@ -3835,7 +3835,7 @@
clear_sys_error();
if (s->s3->renegotiate)
- ssl3_renegotiate_check(s);
+ ssl3_renegotiate_check(s, 0);
s->s3->in_read_app_data = 1;
ret =
s->method->ssl_read_bytes(s, SSL3_RT_APPLICATION_DATA, NULL, buf, len,
@@ -3878,14 +3878,22 @@
return (1);
}
-int ssl3_renegotiate_check(SSL *s)
+/*
+ * Check if we are waiting to do a renegotiation and if so whether now is a
+ * good time to do it. If |initok| is true then we are being called from inside
+ * the state machine so ignore the result of SSL_in_init(s). Otherwise we
+ * should not do a renegotiation if SSL_in_init(s) is true. Returns 1 if we
+ * should do a renegotiation now and sets up the state machine for it. Otherwise
+ * returns 0.
+ */
+int ssl3_renegotiate_check(SSL *s, int initok)
{
int ret = 0;
if (s->s3->renegotiate) {
if (!RECORD_LAYER_read_pending(&s->rlayer)
&& !RECORD_LAYER_write_pending(&s->rlayer)
- && !SSL_in_init(s)) {
+ && (initok || !SSL_in_init(s))) {
/*
* if we are the server, and we have sent a 'RENEGOTIATE'
* message, we need to set the state machine into the renegotiate
@@ -3898,7 +3906,7 @@
ret = 1;
}
}
- return (ret);
+ return ret;
}
/*
