Unverified Commit 74f83c94 authored by Wiktor Kwapisiewicz's avatar Wiktor Kwapisiewicz
Browse files

Add `BigNum::copy_from_slice` 

Unfortunately `BigNum::from_slice` always creates a new BigNum and
cannot be used to initialize an already existing BigNum thus it is not
possible to have a secure BigNum initialized from a slice.

This patch adds the function for overwriting existing BigNum with given
slice bytes. Thus the BigNum can be created using `BigNum::new_secure`
and then overwritten using `BigNum::copy_from_slice`.
parent 6d556313

openssl/src/bn.rs

+24 −0
Original line number Diff line number Diff line
@@ -1080,6 +1080,30 @@ impl BigNum { 
            .map(|p| BigNum::from_ptr(p))

        }

    }



    /// Copies data from a slice overwriting what was in the BigNum.

    ///

    /// This function can be used to copy data from a slice to a

    /// [secure BigNum][`BigNum::new_secure`].

    ///

    /// # Examples

    ///

    /// ```

    /// # use openssl::bn::BigNum;

    /// let mut bignum = BigNum::new().unwrap();

    /// bignum.copy_from_slice(&[0x12, 0x00, 0x34]).unwrap();

    ///

    /// assert_eq!(bignum, BigNum::from_u32(0x120034).unwrap());

    /// ```

    #[corresponds(BN_bin2bn)]

    pub fn copy_from_slice(&mut self, n: &[u8]) -> Result<(), ErrorStack> {

        unsafe {

            assert!(n.len() <= LenType::max_value() as usize);



            cvt_p(ffi::BN_bin2bn(n.as_ptr(), n.len() as LenType, self.0))?;

            Ok(())

        }

    }

}



impl fmt::Debug for BigNumRef {