diff options
Diffstat (limited to 'ssl/record/ssl3_record.c')
| -rw-r--r-- | ssl/record/ssl3_record.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/ssl/record/ssl3_record.c b/ssl/record/ssl3_record.c index f158544789..69f1a64cb3 100644 --- a/ssl/record/ssl3_record.c +++ b/ssl/record/ssl3_record.c @@ -1532,6 +1532,7 @@ int ssl3_cbc_copy_mac(unsigned char *out, #if defined(CBC_MAC_ROTATE_IN_PLACE) unsigned char rotated_mac_buf[64 + EVP_MAX_MD_SIZE]; unsigned char *rotated_mac; + char aux1, aux2, aux3, mask; #else unsigned char rotated_mac[EVP_MAX_MD_SIZE]; #endif @@ -1581,9 +1582,16 @@ int ssl3_cbc_copy_mac(unsigned char *out, #if defined(CBC_MAC_ROTATE_IN_PLACE) j = 0; for (i = 0; i < md_size; i++) { - /* in case cache-line is 32 bytes, touch second line */ - ((volatile unsigned char *)rotated_mac)[rotate_offset ^ 32]; - out[j++] = rotated_mac[rotate_offset++]; + /* + * in case cache-line is 32 bytes, + * load from both lines and select appropriately + */ + aux1 = rotated_mac[rotate_offset & ~32]; + aux2 = rotated_mac[rotate_offset | 32]; + mask = constant_time_eq_8(rotate_offset & ~32, rotate_offset); + aux3 = constant_time_select_8(mask, aux1, aux2); + out[j++] = aux3; + rotate_offset++; rotate_offset &= constant_time_lt_s(rotate_offset, md_size); } #else |