[EXTERNAL] [PATCH v2 2/6] lib: Expand asn1_encode_integer() to variable size integers

Jarkko Sakkinen jarkko at kernel.org
Tue May 21 06:21:13 UTC 2024


On Tue May 21, 2024 at 8:36 AM EEST, Bharat Bhushan wrote:
> > -	data_len -= 2;
> > +	(*data++) = _tag(UNIV, PRIM, INT);
>
> Just for my clarification: 
> 	First index of "data" is updated here with tag and data pointer incremented.
> 	Next comment for continuation
>
> > +	data_len--;
> > 
> > -	data[0] = _tag(UNIV, PRIM, INT);
> > -	if (integer == 0) {
> > -		*d++ = 0;
> > -		goto out;
> > +	if (!memchr_inv(integer, 0, integer_len)) {
> > +		data[1] = 1;
> > +		data[2] = 0;
> > +		return &data[2];
>
> Here we are effectively setting second and third index of original
> "data" pointer as "data" pointer was incremented earlier.
> So second index of original "data" pointer is not touched. Also
> returning 3rd index pointer of original data pointer
>
> Is that intentional?

No! I read the diff few times, and I think you have a point.

Indices should be 0 (length) and 1 (value). I.e. it forms an encoded
version of zero. The last index what it should be, i.e. return address
of the next byte after the encoded integer.

Thanks for pointing this out.

> Thanks
> -Bharat

BR, Jarkko



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