Reject empty records of unexpected type.
The old empty record logic discarded the records at a very low-level.
Let the error bubble up to ssl3_read_bytes so the type mismatch logic
may kick in before the empty record is skipped.
Add tests for when the record in question is application data, before
before the handshake and post ChangeCipherSpec.
BUG=521840
Change-Id: I47dff389cda65d6672b9be39d7d89490331063fa
Reviewed-on: https://boringssl-review.googlesource.com/5754
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/ssl/d1_pkt.c b/ssl/d1_pkt.c
index 6681490..81e9b0a 100644
--- a/ssl/d1_pkt.c
+++ b/ssl/d1_pkt.c
@@ -154,15 +154,6 @@
case ssl_open_record_success:
ssl_read_buffer_consume(ssl, consumed);
- /* Discard empty records.
- * TODO(davidben): This logic should be moved to a higher level. See
- * https://crbug.com/521840.
- * TODO(davidben): Limit the number of empty records as in TLS? This is
- * useful if we also limit discarded packets. */
- if (len == 0) {
- goto again;
- }
-
if (len > 0xffff) {
OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
return -1;
@@ -316,6 +307,11 @@
goto f_err;
}
+ /* Discard empty records. */
+ if (rr->length == 0) {
+ goto start;
+ }
+
if (len <= 0) {
return len;
}
