Move DTLS CCS processing into the state machine

Continuing on from the previous commit this moves the processing of DTLS
CCS messages out of the record layer and into the state machine.

Reviewed-by: Tim Hudson <tjh@openssl.org>

1 files changed, 15 insertions, 55 deletions

diff --git a/ssl/record/rec_layer_d1.c b/ssl/record/rec_layer_d1.c
index 2c8b94f79b..3da4f116bb 100644
--- a/ssl/record/rec_layer_d1.c
+++ b/ssl/record/rec_layer_d1.c
@@ -379,8 +379,9 @@ int dtls1_process_buffered_records(SSL *s)
  * (possibly multiple records if we still don't have anything to return).
  *
  * This function must handle any surprises the peer may have for us, such as
- * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
- * a surprise, but handled as if it were), or renegotiation requests.
+ * Alert records (e.g. close_notify) or renegotiation requests. ChangeCipherSpec
+ * messages are treated as if they were handshake messages *if* the |recd_type|
+ * argument is non NULL.
  * Also if record payloads contain fragments too small to process, we store
  * them until there is enough for the respective protocol (the record protocol
  * may use arbitrary fragmentation and even interleaving):
@@ -538,9 +539,14 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
         return (0);
     }
 
-    if (type == SSL3_RECORD_get_type(rr)) {
-        /* SSL3_RT_APPLICATION_DATA or
-         * SSL3_RT_HANDSHAKE */
+    if (type == SSL3_RECORD_get_type(rr)
+            || (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC
+                && type == SSL3_RT_HANDSHAKE && recvd_type != NULL)) {
+        /*
+         * SSL3_RT_APPLICATION_DATA or
+         * SSL3_RT_HANDSHAKE or
+         * SSL3_RT_CHANGE_CIPHER_SPEC
+         */
         /*
          * make sure that we are not getting application data when we are
          * doing a handshake for the first time
@@ -552,6 +558,9 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
             goto f_err;
         }
 
+        if (recvd_type != NULL)
+            *recvd_type = SSL3_RECORD_get_type(rr);
+
         if (len <= 0)
             return (len);
 
@@ -858,59 +867,11 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
     }
 
     if (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC) {
-        unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;
-
-        if (s->version == DTLS1_BAD_VER)
-            ccs_hdr_len = 3;
-
-        /*
-         * 'Change Cipher Spec' is just a single byte, so we know exactly
-         * what the record payload has to look like
-         */
-        /* XDTLS: check that epoch is consistent */
-        if ((SSL3_RECORD_get_length(rr) != ccs_hdr_len)
-                || (SSL3_RECORD_get_off(rr) != 0)
-                || (SSL3_RECORD_get_data(rr)[0] != SSL3_MT_CCS)) {
-            i = SSL_AD_ILLEGAL_PARAMETER;
-            SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC);
-            goto err;
-        }
-
-        SSL3_RECORD_set_length(rr, 0);
-
-        if (s->msg_callback)
-            s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
-                SSL3_RECORD_get_data(rr), 1, s, s->msg_callback_arg);
-
         /*
          * We can't process a CCS now, because previous handshake messages
          * are still missing, so just drop it.
          */
-        if (!s->d1->change_cipher_spec_ok) {
-            goto start;
-        }
-
-        s->d1->change_cipher_spec_ok = 0;
-
-        s->s3->change_cipher_spec = 1;
-        if (!ssl3_do_change_cipher_spec(s))
-            goto err;
-
-        /* do this whenever CCS is processed */
-        dtls1_reset_seq_numbers(s, SSL3_CC_READ);
-
-        if (s->version == DTLS1_BAD_VER)
-            s->d1->handshake_read_seq++;
-
-#ifndef OPENSSL_NO_SCTP
-        /*
-         * Remember that a CCS has been received, so that an old key of
-         * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no
-         * SCTP is used
-         */
-        BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
-#endif
-
+        SSL3_RECORD_set_length(rr, 0);
         goto start;
     }
 
@@ -1026,7 +987,6 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
 
  f_err:
     ssl3_send_alert(s, SSL3_AL_FATAL, al);
- err:
     return (-1);
 }