Remove dependency on regular num-bigint

src/certificate.rs

@@ -476,7 +476,8 @@ impl Certificate {
             _ => return Err(Error::InvalidObject),
         };
 
-        let serial = parsed_cert.tbs_certificate.serial.into();
+        let serial = Serial::try_from(parsed_cert.tbs_certificate.serial.to_bytes_be().as_slice())
+            .map_err(|_| Error::InvalidObject)?;
         let issuer = parsed_cert.tbs_certificate.issuer.to_string();
         let subject = parsed_cert.tbs_certificate.subject.to_string();
         let subject_pki = PublicKeyInfo::parse(&parsed_cert.tbs_certificate.subject_pki)?;

src/key.rs

@@ -59,7 +59,7 @@ use crate::{
 use elliptic_curve::weierstrass::PublicKey as EcPublicKey;
 use log::{error, warn};
 #[cfg(feature = "untested")]
-use num_bigint_rsa::traits::ModInverse;
+use num_bigint::traits::ModInverse;
 #[cfg(feature = "untested")]
 use num_integer::Integer;
 #[cfg(feature = "untested")]