Update DTLS code to match CBC decoding in TLS.
This change updates the DTLS code to match the constant-time CBC
behaviour in the TLS.
(cherry picked from commit 9f27de170d1b7bef3d46d41382dc4dafde8b3900)
diff --git a/ssl/d1_enc.c b/ssl/d1_enc.c
index da42348..712c464 100644
--- a/ssl/d1_enc.c
+++ b/ssl/d1_enc.c
@@ -126,6 +126,14 @@
#include <openssl/des.h>
#endif
+/* dtls1_enc encrypts/decrypts the record in |s->wrec| / |s->rrec|, respectively.
+ *
+ * Returns:
+ * 0: (in non-constant time) if the record is publically invalid (i.e. too
+ * short etc).
+ * 1: if the record's padding is valid / the encryption was successful.
+ * -1: if the record's padding/AEAD-authenticator is invalid or, if sending,
+ * an internal error occured. */
int dtls1_enc(SSL *s, int send)
{
SSL3_RECORD *rec;
@@ -165,8 +173,7 @@
if (EVP_MD_CTX_md(s->read_hash))
{
mac_size=EVP_MD_CTX_size(s->read_hash);
- if (mac_size < 0)
- return -1;
+ OPENSSL_assert(mac_size >= 0);
}
ds=s->enc_read_ctx;
rec= &(s->s3->rrec);
@@ -231,7 +238,7 @@
if (!send)
{
if (l == 0 || l%bs != 0)
- return -1;
+ return 0;
}
EVP_Cipher(ds,rec->data,rec->input,l);
