Re: dc: do {} while() as an arg in bn_check()

[Otto Moerbeek]

On Sun, Feb 26, 2017 at 11:49:13AM +0100, Daniel Cegiełka wrote:

> 2017-02-26 8:27 GMT+01:00 Otto Moerbeek <o...@drijf.net>:
> > On Sat, Feb 25, 2017 at 11:28:43PM +0100, Daniel Cegiełka wrote:
> >
> 
> >
> > Bleh, they could have changed the implementation without changing the
> > API but they choose not to and place the burden on the user of the lib.
> >
> > Easy "fix" would be to remove the BN_check, but in current compat mode
> > that would lead to a unchecked mem allocation. Don't like that at all.
> >
> 
> https://github.com/openbsd/src/blob/master/lib/libcrypto/bn/bn_lib.c#L564
> 
> BN_set_word() is not mark as DEPRECATED and bn_check() call it many times:
> 
> $ grep BN_set_word bcode.c|grep bn_check
>         bn_check(BN_set_word(a, 10));
>         bn_check(BN_set_word(p, abs_scale));
>             bn_check(BN_set_word(f, rem));
>         bn_check(BN_set_word(a, 10));
>         bn_check(BN_set_word(p, n->scale));
>     bn_check(BN_set_word(n->number, bmachine.scale));
>     bn_check(BN_set_word(n->number, bmachine.obase));
>     bn_check(BN_set_word(n->number, bmachine.ibase));
>     bn_check(BN_set_word(n->number, i));
>         bn_check(BN_set_word(n->number, scale));
>             bn_check(BN_set_word(n->number, digits));
>             bn_check(BN_set_word(n->number, digits));
>     bn_check(BN_set_word(a->number, BN_get_word(a->number) ? 0 : 1));
>     bn_check(BN_set_word(r->number,
>     bn_check(BN_set_word(r->number,
>     bn_check(BN_set_word(r->number,
> 
> so instead BN_zero we can use BN_set_word() directly:
> 
> bn_check(BN_set_word(BIGNUM_VAR, 0));
> 
> Daniel

Indeed, commited,

Thanks,
                
        -Otto

> 
> 
> >         -Otto

> diff -urN dc.orig/bcode.c dc.new/bcode.c
> --- dc.orig/bcode.c   Sat Feb 25 10:58:20 2017
> +++ dc.new/bcode.c    Sun Feb 26 10:40:55 2017
> @@ -386,7 +386,7 @@
>       bn_checkp(BN_copy(i, n->number));
>  
>       if (n->scale == 0 && f != NULL)
> -             bn_check(BN_zero(f));
> +             bn_check(BN_set_word(f, 0));
>       else if (n->scale < sizeof(factors)/sizeof(factors[0])) {
>               rem = BN_div_word(i, factors[n->scale]);
>               if (f != NULL)
> @@ -804,7 +804,7 @@
>               v = stack_tos(&bmachine.reg[idx]);
>               if (v == NULL) {
>                       n = new_number();
> -                     bn_check(BN_zero(n->number));
> +                     bn_check(BN_set_word(n->number, 0));
>                       push_number(n);
>               } else
>                       push(stack_dup_value(v, &copy));
> @@ -888,7 +888,7 @@
>                       v = frame_retrieve(stack, idx);
>                       if (v == NULL || v->type == BCODE_NONE) {
>                               n = new_number();
> -                             bn_check(BN_zero(n->number));
> +                             bn_check(BN_set_word(n->number, 0));
>                               push_number(n);
>                       }
>                       else
> diff -urN dc.orig/inout.c dc.new/inout.c
> --- dc.orig/inout.c   Thu Feb  2 22:16:20 2017
> +++ dc.new/inout.c    Sun Feb 26 10:41:17 2017
> @@ -186,7 +186,7 @@
>       u_int           i;
>  
>       n = new_number();
> -     bn_check(BN_zero(n->number));
> +     bn_check(BN_set_word(n->number, 0));
>  
>       while ((ch = (*src->vtable->readchar)(src)) != EOF) {
>