Re: Add GRND_INSECURE from Linux 5.6 to sys/random.h

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

On 03/04/2020 18:12, Joseph Myers wrote:
> This patch adds the GRND_INSECURE constant from Linux 5.6 to glibc's
> sys/random.h.  This is also added to the documentation.  The constant
> acts as a no-op for the Hurd implementation (as that doesn't check
> whether the flags are known), which is semantically fine, while older
> Linux kernels reject unknown flags with an EINVAL error.
> 
> Tested for x86_64.

LGTM, it follows Linux commit 75551dbf112c9. 

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

> 
> diff --git a/manual/crypt.texi b/manual/crypt.texi
> index c41b911c8f..af23dd7847 100644
> --- a/manual/crypt.texi
> +++ b/manual/crypt.texi
> @@ -301,6 +301,9 @@ booted and the randomness source has not yet been initialized.
>  @item GRND_NONBLOCK
>  Instead of blocking, return to the caller immediately if no data is
>  available.
> +
> +@item GRND_INSECURE
> +Write random data that may not be cryptographically secure.
>  @end table
>  
>  Unlike @code{getentropy}, the @code{getrandom} function is a
> diff --git a/stdlib/sys/random.h b/stdlib/sys/random.h
> index b351ef5c8c..1df6e9b844 100644
> --- a/stdlib/sys/random.h
> +++ b/stdlib/sys/random.h
> @@ -25,6 +25,7 @@
>  /* Flags for use with getrandom.  */
>  #define GRND_NONBLOCK 0x01
>  #define GRND_RANDOM 0x02
> +#define GRND_INSECURE 0x04
>  
>  __BEGIN_DECLS
>  
>