diff options
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/ec/ecx_meth.c | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/crypto/ec/ecx_meth.c b/crypto/ec/ecx_meth.c index 776e88de36..d141fe7b81 100644 --- a/crypto/ec/ecx_meth.c +++ b/crypto/ec/ecx_meth.c @@ -854,6 +854,7 @@ static const EVP_PKEY_METHOD ed448_pkey_meth = { #ifdef S390X_EC_ASM # include "s390x_arch.h" +# include "internal/constant_time.h" static void s390x_x25519_mod_p(unsigned char u[32]) { @@ -867,16 +868,16 @@ static void s390x_x25519_mod_p(unsigned char u[32]) u_red[31] = (unsigned char)c; c >>= 8; - for (i = 30; c > 0 && i >= 0; i--) { + for (i = 30; i >= 0; i--) { c += (unsigned int)u_red[i]; u_red[i] = (unsigned char)c; c >>= 8; } - if (u_red[0] & 0x80) { - u_red[0] &= 0x7f; - memcpy(u, u_red, sizeof(u_red)); - } + c = (u_red[0] & 0x80) >> 7; + u_red[0] &= 0x7f; + constant_time_cond_swap_buff(0 - (unsigned char)c, + u, u_red, sizeof(u_red)); } static void s390x_x448_mod_p(unsigned char u[56]) @@ -901,14 +902,14 @@ static void s390x_x448_mod_p(unsigned char u[56]) u_red[27] = (unsigned char)c; c >>= 8; - for (i = 26; c > 0 && i >= 0; i--) { + for (i = 26; i >= 0; i--) { c += (unsigned int)u_red[i]; u_red[i] = (unsigned char)c; c >>= 8; } - if (c) - memcpy(u, u_red, sizeof(u_red)); + constant_time_cond_swap_buff(0 - (unsigned char)c, + u, u_red, sizeof(u_red)); } static int s390x_x25519_mul(unsigned char u_dst[32], |