use rpgp directly

src/pgp/hash.rs

@@ -0,0 +1,19 @@
+use sha2::{Digest, Sha256};
+use std::slice;
+
+use crate::pgp::cvec;
+
+/// Calculate the SHA256 hash of the given bytes.
+#[no_mangle]
+pub unsafe extern "C" fn rpgp_hash_sha256(
+    bytes_ptr: *const u8,
+    bytes_len: libc::size_t,
+) -> *mut cvec {
+    assert!(!bytes_ptr.is_null());
+    assert!(bytes_len > 0);
+
+    let bytes = slice::from_raw_parts(bytes_ptr, bytes_len);
+    let result = Sha256::digest(bytes);
+
+    Box::into_raw(Box::new(result.to_vec().into()))
+}