CBC record splitting.
This patch removes support for empty records (which is almost
universally disabled via SSL_OP_ALL) and adds optional support for 1/n-1
record splitting.
The latter is not enabled by default, since it's not typically used on
servers, but it should be enabled in web browsers since there are known
attacks in that case (see BEAST).
diff --git a/ssl/t1_enc.c b/ssl/t1_enc.c
index 7897519..7c73e35 100644
--- a/ssl/t1_enc.c
+++ b/ssl/t1_enc.c
@@ -721,22 +721,22 @@
{ int z; for (z=0; z<num; z++) printf("%02X%c",p1[z],((z+1)%16)?' ':'\n'); }
#endif
- if (!(s->options & SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS)
- && s->method->version <= TLS1_VERSION)
+ if (s->method->version <= TLS1_VERSION &&
+ (s->mode & SSL_MODE_CBC_RECORD_SPLITTING) != 0)
{
/* enable vulnerability countermeasure for CBC ciphers with
* known-IV problem (http://www.openssl.org/~bodo/tls-cbc.txt)
*/
- s->s3->need_empty_fragments = 1;
+ s->s3->need_record_splitting = 1;
if (s->session->cipher != NULL)
{
if (s->session->cipher->algorithm_enc == SSL_eNULL)
- s->s3->need_empty_fragments = 0;
+ s->s3->need_record_splitting = 0;
#ifndef OPENSSL_NO_RC4
if (s->session->cipher->algorithm_enc == SSL_RC4)
- s->s3->need_empty_fragments = 0;
+ s->s3->need_record_splitting = 0;
#endif
}
}