diff --git a/openssl/src/hash.rs b/openssl/src/hash.rs index b25eded94..f66c5ce01 100644 --- a/openssl/src/hash.rs +++ b/openssl/src/hash.rs @@ -194,6 +194,8 @@ unsafe impl Send for MessageDigest {} enum State { Reset, Updated, + #[cfg(ossl330)] + Squeeze, Finalized, } @@ -260,6 +262,8 @@ impl Hasher { Updated => { self.finish()?; } + #[cfg(ossl330)] + Squeeze => (), Finalized => (), } unsafe { @@ -274,6 +278,19 @@ impl Hasher { if self.state == Finalized { self.init()?; } + #[cfg(ossl330)] + if self.state == Squeeze { + // [`EVP_DigestUpdate`], depending on the implementation, may allow Updates after Squeezes. + // But, [FIPS 202], as shown in Figure 7, has a distinguished absorbing phase followed by a squeezing phase. + // Indeed, the [`sha3.c`] implmentation disallows Updates after Squeezes. + // For consistency, we always return an error when Update is called after Squeeze. + // + // [`EVP_DigestUpdate`]: https://github.com/openssl/openssl/blob/b3bb214720f20f3b126ae4b9c330e9a48b835415/crypto/evp/digest.c#L385-L393 + // [FIPS 202]: https://dx.doi.org/10.6028/NIST.FIPS.202 + // [`sha3.c`]: https://github.com/openssl/openssl/blob/b3bb214720f20f3b126ae4b9c330e9a48b835415/crypto/sha/sha3.c#L52-L63 + let errors = ErrorStack::get(); + return Err(errors); + } unsafe { cvt(ffi::EVP_DigestUpdate( self.ctx, @@ -285,6 +302,21 @@ impl Hasher { Ok(()) } + /// Squeezes buf out of the hasher. Can be called multiple times, unlike `finish_xof`. + /// The output will be as long as the buf. + #[cfg(ossl330)] + pub fn squeeze_xof(&mut self, buf: &mut [u8]) -> Result<(), ErrorStack> { + unsafe { + cvt(ffi::EVP_DigestSqueeze( + self.ctx, + buf.as_mut_ptr(), + buf.len(), + ))?; + self.state = Squeeze; + Ok(()) + } + } + /// Returns the hash of the data written and resets the non-XOF hasher. pub fn finish(&mut self) -> Result { if self.state == Finalized { @@ -481,6 +513,21 @@ mod tests { assert_eq!(buf, expected); } + /// Squeezes the expected length by doing two squeezes. + #[cfg(ossl330)] + fn hash_xof_squeeze_test(hashtype: MessageDigest, hashtest: &(&str, &str)) { + let data = Vec::from_hex(hashtest.0).unwrap(); + let mut h = Hasher::new(hashtype).unwrap(); + h.update(&data).unwrap(); + + let expected = Vec::from_hex(hashtest.1).unwrap(); + let mut buf = vec![0; expected.len()]; + assert!(expected.len() > 10); + h.squeeze_xof(&mut buf[..10]).unwrap(); + h.squeeze_xof(&mut buf[10..]).unwrap(); + assert_eq!(buf, expected); + } + fn hash_recycle_test(h: &mut Hasher, hashtest: &(&str, &str)) { h.write_all(&Vec::from_hex(hashtest.0).unwrap()).unwrap(); let res = h.finish().unwrap(); @@ -537,6 +584,40 @@ mod tests { assert_eq!(&*res, &*null); } + #[cfg(ossl330)] + #[test] + fn test_finish_then_squeeze() { + let digest = MessageDigest::shake_128(); + let mut h = Hasher::new(digest).unwrap(); + let mut buf = vec![0; digest.size()]; + h.finish_xof(&mut buf).unwrap(); + h.squeeze_xof(&mut buf) + .expect_err("squeezing after finalize should fail"); + } + + #[cfg(ossl330)] + #[test] + fn test_squeeze_then_update() { + let digest = MessageDigest::shake_128(); + let data = Vec::from_hex(MD5_TESTS[6].0).unwrap(); + let mut h = Hasher::new(digest).unwrap(); + let mut buf = vec![0; digest.size()]; + h.squeeze_xof(&mut buf).unwrap(); + h.update(&data) + .expect_err("updating after squeeze should fail"); + } + + #[cfg(ossl330)] + #[test] + fn test_squeeze_then_finalize() { + let digest = MessageDigest::shake_128(); + let mut h = Hasher::new(digest).unwrap(); + let mut buf = vec![0; digest.size()]; + h.squeeze_xof(&mut buf).unwrap(); + h.finish_xof(&mut buf) + .expect_err("finalize after squeeze should fail"); + } + #[test] #[allow(clippy::redundant_clone)] fn test_clone() { @@ -710,6 +791,8 @@ mod tests { for test in tests.iter() { hash_xof_test(MessageDigest::shake_128(), test); + #[cfg(ossl330)] + hash_xof_squeeze_test(MessageDigest::shake_128(), test); } assert_eq!(MessageDigest::shake_128().block_size(), 168); @@ -730,6 +813,8 @@ mod tests { for test in tests.iter() { hash_xof_test(MessageDigest::shake_256(), test); + #[cfg(ossl330)] + hash_xof_squeeze_test(MessageDigest::shake_256(), test); } assert_eq!(MessageDigest::shake_256().block_size(), 136);