components/library/openssl-3/patches/05-bn_sqr_mont.patch

   1 This patch provides a workaround for https://github.com/openssl/openssl/issues/15587
   2
   3 This patch changes Montgomery squaring implementation for SPARCv9
   4 so that it uses less optimized code path (within code path that is
   5 already heavily optimized and written in handcrafted assembly).
   6 Basically, instead of using dedicated Montgomery squaring procedure ( A == B ),
   7 it will use the generic Montgomery multiplication procedure ( A != B ).
   8
   9 This results in performance degradation, until proper fix is determined.
  10 When calling ECDSA_sign()/ECDSA_verify() back to back in FIPS mode with the
  11 NID_secp521r1 curve, using 64-bit program on a LDOM with 16 SPARC-M7 CPUs on a
  12 SPARC T7-1 machine, the performance degradation was 5 percent on average.
  13
  14 --- openssl-3.4.0/crypto/bn/asm/sparcv9-mont.pl.orig
  15 +++ openssl-3.4.0/crypto/bn/asm/sparcv9-mont.pl
  16 @@ -117,7 +117,7 @@
  17         ld      [$np],$car1             ! np[0]
  18         sub     %o7,$bias,%sp           ! alloca
  19         ld      [$np+4],$npj            ! np[1]
  20 -       be,pt   SIZE_T_CC,.Lbn_sqr_mont
  21 +       nop                             ! disable bn_sqr_mont for now
  22         mov     12,$j
  23
  24         mulx    $car0,$mul0,$car0       ! ap[0]*bp[0]