Enable TLS 1.2 ciphers in DTLS 1.2.

Port TLS 1.2 GCM code to DTLS. Enable use of TLS 1.2 only ciphers when in
DTLS 1.2 mode too.

1 files changed, 24 insertions, 22 deletions

diff --git a/ssl/d1_pkt.c b/ssl/d1_pkt.c
index b7ff9a8705..995e6576e0 100644
--- a/ssl/d1_pkt.c
+++ b/ssl/d1_pkt.c
@@ -1466,10 +1466,10 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len,
 	unsigned char *p,*pseq;
 	int i,mac_size,clear=0;
 	int prefix_len = 0;
+	int eivlen;
 	SSL3_RECORD *wr;
 	SSL3_BUFFER *wb;
 	SSL_SESSION *sess;
-	int bs;
 
 	/* first check if there is a SSL3_BUFFER still being written
 	 * out.  This will happen with non blocking IO */
@@ -1554,18 +1554,27 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len,
 	pseq=p; 
 	p+=10;
 
-	/* lets setup the record stuff. */
-
-	/* Make space for the explicit IV in case of CBC.
-	 * (this is a bit of a boundary violation, but what the heck).
-	 */
-	if ( s->enc_write_ctx && 
-		(EVP_CIPHER_mode( s->enc_write_ctx->cipher ) & EVP_CIPH_CBC_MODE))
-		bs = EVP_CIPHER_block_size(s->enc_write_ctx->cipher);
-	else
-		bs = 0;
+	/* Explicit IV length, block ciphers appropriate version flag */
+	if (s->enc_write_ctx)
+		{
+		int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
+		if (mode == EVP_CIPH_CBC_MODE)
+			{
+			eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
+			if (eivlen <= 1)
+				eivlen = 0;
+			}
+		/* Need explicit part of IV for GCM mode */
+		else if (mode == EVP_CIPH_GCM_MODE)
+			eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
+		else
+			eivlen = 0;
+		}
+	else 
+		eivlen = 0;
 
-	wr->data=p + bs;  /* make room for IV in case of CBC */
+	/* lets setup the record stuff. */
+	wr->data=p + eivlen;  /* make room for IV in case of CBC */
 	wr->length=(int)len;
 	wr->input=(unsigned char *)buf;
 
@@ -1593,7 +1602,7 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len,
 
 	if (mac_size != 0)
 		{
-		if(s->method->ssl3_enc->mac(s,&(p[wr->length + bs]),1) < 0)
+		if(s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
 			goto err;
 		wr->length+=mac_size;
 		}
@@ -1602,15 +1611,8 @@ int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len,
 	wr->input=p;
 	wr->data=p;
 
-
-	/* ssl3_enc can only have an error on read */
-	if (bs)	/* bs != 0 in case of CBC */
-		{
-		RAND_pseudo_bytes(p,bs);
-		/* master IV and last CBC residue stand for
-		 * the rest of randomness */
-		wr->length += bs;
-		}
+	if (eivlen)
+		wr->length += eivlen;
 
 	s->method->ssl3_enc->enc(s,1);