Remove repeated code in dtls1_get_record.

The "if" is a bit ugly, but this does remove a lot of repetitive code.
This will be converted to CBS later as well.

ok miod@
jsing@ roughly ok with it after seeing the CBS version

1 files changed, 16 insertions, 40 deletions

diff --git a/lib/libssl/d1_pkt.c b/lib/libssl/d1_pkt.c
index 60c1236f53a..68571c8fd06 100644
--- a/lib/libssl/d1_pkt.c
+++ b/lib/libssl/d1_pkt.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: d1_pkt.c,v 1.42 2015/06/17 07:29:33 doug Exp $ */
+/* $OpenBSD: d1_pkt.c,v 1.43 2015/07/18 22:28:53 doug Exp $ */
 /*
  * DTLS implementation written by Nagendra Modadugu
  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
@@ -484,7 +484,13 @@ dtls1_get_record(SSL *s)
 		return 1;
 
 	/* get something from the wire */
+	if (0) {
 again:
+		/* dump this record on all retries */
+		rr->length = 0;
+		s->packet_length = 0;
+	}
+
 	/* check if we have the header */
 	if ((s->rstate != SSL_ST_READ_BODY) ||
 		(s->packet_length < DTLS1_RT_HEADER_LENGTH)) {
@@ -494,10 +500,8 @@ again:
 			return(n); /* error or non-blocking */
 
 		/* this packet contained a partial record, dump it */
-		if (s->packet_length != DTLS1_RT_HEADER_LENGTH) {
-			s->packet_length = 0;
+		if (s->packet_length != DTLS1_RT_HEADER_LENGTH)
 			goto again;
-		}
 
 		s->rstate = SSL_ST_READ_BODY;
 
@@ -519,27 +523,18 @@ again:
 
 		/* Lets check version */
 		if (!s->first_packet) {
-			if (version != s->version) {
+			if (version != s->version)
 				/* unexpected version, silently discard */
-				rr->length = 0;
-				s->packet_length = 0;
 				goto again;
-			}
 		}
 
-		if ((version & 0xff00) != (s->version & 0xff00)) {
+		if ((version & 0xff00) != (s->version & 0xff00))
 			/* wrong version, silently discard record */
-			rr->length = 0;
-			s->packet_length = 0;
 			goto again;
-		}
 
-		if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
+		if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
 			/* record too long, silently discard it */
-			rr->length = 0;
-			s->packet_length = 0;
 			goto again;
-		}
 
 		/* now s->rstate == SSL_ST_READ_BODY */
 	}
@@ -554,11 +549,8 @@ again:
 			return(n); /* error or non-blocking io */
 
 		/* this packet contained a partial record, dump it */
-		if (n != i) {
-			rr->length = 0;
-			s->packet_length = 0;
+		if (n != i)
 			goto again;
-		}
 
 		/* now n == rr->length,
 		 * and s->packet_length == DTLS1_RT_HEADER_LENGTH + rr->length */
@@ -567,13 +559,8 @@ again:
 
 	/* match epochs.  NULL means the packet is dropped on the floor */
 	bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
-	if (bitmap == NULL) {
-		rr->length = 0;
-		s->packet_length = 0;
-		/* dump this record */
+	if (bitmap == NULL)
 		goto again;
-		/* get another record */
-	}
 
 	/*
 	 * Check whether this is a repeat, or aged record.
@@ -584,12 +571,8 @@ again:
 	 */
 	if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE &&
 	    p != NULL && *p == SSL3_MT_CLIENT_HELLO) &&
-	    !dtls1_record_replay_check(s, bitmap)) {
-		rr->length = 0;
-		s->packet_length=0; /* dump this record */
+	    !dtls1_record_replay_check(s, bitmap))
 		goto again;
-		/* get another record */
-	}
 
 	/* just read a 0 length packet */
 	if (rr->length == 0)
@@ -608,23 +591,16 @@ again:
 			/* Mark receipt of record. */
 			dtls1_record_bitmap_update(s, bitmap);
 		}
-		rr->length = 0;
-		s->packet_length = 0;
 		goto again;
 	}
 
-	if (!dtls1_process_record(s)) {
-		rr->length = 0;
-		s->packet_length = 0;
-		/* dump this record */
+	if (!dtls1_process_record(s))
 		goto again;
-		/* get another record */
-	}
+
 	/* Mark receipt of record. */
 	dtls1_record_bitmap_update(s, bitmap);
 
 	return (1);
-
 }
 
 /* Return up to 'len' payload bytes received in 'type' records.