[openssl] OpenSSL_1_0_2-stable update

[Matt Caswell]

The branch OpenSSL_1_0_2-stable has been updated
       via  55611d549bcf65e0de04938adbf403ccf02f241b (commit)
      from  7fafaf27c2c2990fde2798424a38ce8443dae595 (commit)


- Log -----------------------------------------------------------------
commit 55611d549bcf65e0de04938adbf403ccf02f241b
Author: Cesar Pereida Garcia <cesar.pereidagarcia at tut.fi>
Date:   Mon Aug 19 10:33:14 2019 +0300

    Fix SCA vulnerability when using PVK and MSBLOB key formats
    
    This commit addresses a side-channel vulnerability present when
    PVK and MSBLOB key formats are loaded into OpenSSL.
    The public key was not computed using a constant-time exponentiation
    function.
    
    This issue was discovered and reported by the NISEC group at TAU Finland.
    
    Reviewed-by: Nicola Tuveri <nic.tuv at gmail.com>
    Reviewed-by: Bernd Edlinger <bernd.edlinger at hotmail.de>
    Reviewed-by: Matt Caswell <matt at openssl.org>
    (Merged from https://github.com/openssl/openssl/pull/9638)

-----------------------------------------------------------------------

Summary of changes:
 crypto/pem/pvkfmt.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/crypto/pem/pvkfmt.c b/crypto/pem/pvkfmt.c
index f376f594b1..ff5674a99f 100644
--- a/crypto/pem/pvkfmt.c
+++ b/crypto/pem/pvkfmt.c
@@ -327,6 +327,8 @@ static EVP_PKEY *b2i_dss(const unsigned char **in, unsigned int length,
     } else {
         if (!read_lebn(&p, 20, &dsa->priv_key))
             goto memerr;
+        /* Set constant time flag before public key calculation */
+        BN_set_flags(dsa->priv_key, BN_FLG_CONSTTIME);
         /* Calculate public key */
         if (!(dsa->pub_key = BN_new()))
             goto memerr;