feat: add parse_padding, padding_to_string

src/rsautil.rs

@@ -1,4 +1,5 @@
 use openssl::bn::{BigNum, BigNumContext};
+use openssl::rsa::Padding;
 use rust_util::XResult;
 
 #[derive(Debug)]
@@ -31,6 +32,26 @@ pub fn clone_big_num(n: &BigNum) -> XResult<BigNum> {
     Ok(opt_result!(BigNum::from_slice(n.to_vec().as_slice()), "Clone big num:{}, failed: {}", n))
 }
 
+pub fn parse_padding(padding_opt: Option<&str>) -> XResult<Padding> {
+    Ok(match padding_opt {
+        Some("oaep") | Some("pkcs1_oaep") => Padding::PKCS1_OAEP,
+        Some("pss") | Some("pkcs1_pss") => Padding::PKCS1_PSS,
+        Some("none") => Padding::NONE,
+        Some("pkcs1") | None => Padding::PKCS1,
+        Some(p) => return simple_error!("Not supported padding: {}", p),
+    })
+}
+
+pub fn padding_to_string(padding: Padding) -> &'static str {
+    match padding {
+        Padding::NONE => "none",
+        Padding::PKCS1 => "pkcs1",
+        Padding::PKCS1_PSS => "pkcs1_pss",
+        Padding::PKCS1_OAEP => "pkcs1_oaep",
+        _ => "unknown",
+    }
+}
+
 fn inner_from(p: BigNum, q: BigNum, e: BigNum) -> XResult<RsaCrt> {
     let mut n = BigNum::new()?;
     n.checked_mul(&p, &q, &mut BigNumContext::new().unwrap())?;