Check for buffered handshake messages on cipher change in DTLS.
This is the equivalent of FragmentAcrossChangeCipherSuite for DTLS. It
is possible for us to, while receiving pre-CCS handshake messages, to
buffer up a message with sequence number meant for a post-CCS Finished.
When we then get to the new epoch and attempt to read the Finished, we
will process the buffered Finished although it was sent with the wrong
encryption.
Move ssl_set_{read,write}_state to SSL_PROTOCOL_METHOD hooks as this is
a property of the transport. Notably, read_state may fail. In DTLS
check the handshake buffer size. We could place this check in
read_change_cipher_spec, but TLS 1.3 has no ChangeCipherSpec message, so
we will need to implement this at the cipher change point anyway. (For
now, there is only an assert on the TLS side. This will be replaced with
a proper check in TLS 1.3.)
Change-Id: Ia52b0b81e7db53e9ed2d4f6d334a1cce13e93297
Reviewed-on: https://boringssl-review.googlesource.com/8790
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
diff --git a/include/openssl/ssl.h b/include/openssl/ssl.h
index cb5a65f..44026aa 100644
--- a/include/openssl/ssl.h
+++ b/include/openssl/ssl.h
@@ -4714,6 +4714,7 @@
#define SSL_R_UNSUPPORTED_PROTOCOL_FOR_CUSTOM_KEY 252
#define SSL_R_NO_COMMON_SIGNATURE_ALGORITHMS 253
#define SSL_R_DOWNGRADE_DETECTED 254
+#define SSL_R_BUFFERED_MESSAGES_ON_CIPHER_CHANGE 255
#define SSL_R_SSLV3_ALERT_CLOSE_NOTIFY 1000
#define SSL_R_SSLV3_ALERT_UNEXPECTED_MESSAGE 1010
#define SSL_R_SSLV3_ALERT_BAD_RECORD_MAC 1020
