refactor(picky-asn1-der): remove num-bigint-dig (#427)

Author: RRRadicalEdward

Cargo.lock

@@ -25,7 +25,7 @@ serde_bytes = "0.11"
 base64 = "0.22"
 pretty_assertions = "1.4"
 serde_bytes = "0.11"
-num-bigint-dig = "0.8"# TODO: use `crypto-bigint` instead
+crypto-bigint = { version = "0.7.0-rc.8", default-features = false, features = ["alloc"] }
 oid = { version = "0.2", default-features = false, features = ["serde_support"] }
 
 [features]

picky-asn1-der/Cargo.toml

@@ -17,7 +17,7 @@
 use super::ocsp_request::AlgorithmIdentifier;
 use base64::Engine as _;
 use base64::engine::general_purpose;
-use num_bigint_dig::BigInt;
+use crypto_bigint::BoxedUint;
 use oid::prelude::*;
 use picky_asn1::wrapper::*;
 use serde::{Deserialize, Serialize};
@@ -78,7 +78,10 @@ fn subject_public_key_info() {
     ]);
     check!(modulus: IntegerAsn1 in encoded[28..289]);
 
-    let public_exponent: IntegerAsn1 = BigInt::from(65537).to_signed_bytes_be().into();
+    let public_exponent: IntegerAsn1 = BoxedUint::from(65537u32)
+        .to_be_bytes_trimmed_vartime()
+        .into_vec()
+        .into();
     check!(public_exponent: IntegerAsn1 in encoded[289..294]);
 
     // RSA public key

picky-asn1-der/tests/pki_tests/rsa_public_key.rs

@@ -59,7 +59,7 @@ use crate::pki_tests::rsa_public_key::{RSAPublicKey, SubjectPublicKeyInfoRsa};
 use crate::pki_tests::version::{Version, implicit_app0_version_is_default};
 use base64::Engine as _;
 use base64::engine::general_purpose;
-use num_bigint_dig::BigInt;
+use crypto_bigint::BoxedUint;
 use oid::prelude::*;
 use picky_asn1::bit_string::BitString;
 use picky_asn1::date::Date;
@@ -176,7 +176,10 @@ fn x509_v3_certificate() {
         },
         subject_public_key: RSAPublicKey {
             modulus: IntegerAsn1::from_bytes_be_signed(encoded[165..422].to_vec()),
-            public_exponent: BigInt::from(65537).to_signed_bytes_be().into(),
+            public_exponent: BoxedUint::from(65537u32)
+                .to_be_bytes_trimmed_vartime()
+                .into_vec()
+                .into(),
         }
         .into(),
     };

picky-asn1-der/tests/pki_tests/x509_v3_certificate.rs

@@ -1,8 +1,6 @@
-extern crate num_bigint_dig as num_bigint;
-
 mod pki_tests;
 
-use num_bigint::ToBigInt;
+use crypto_bigint::BoxedUint;
 use oid::prelude::*;
 use picky_asn1::bit_string::BitString;
 use picky_asn1::date::{Date, GeneralizedTime, UTCTime};
@@ -107,7 +105,7 @@ fn big_integer() {
 #[test]
 fn small_integer() {
     let buffer = [0x02, 0x01, 0x03];
-    let big_integer = IntegerAsn1::from(3.to_bigint().unwrap().to_signed_bytes_be());
+    let big_integer = IntegerAsn1::from(BoxedUint::from(3u32).to_be_bytes_trimmed_vartime().into_vec());
 
     assert!(big_integer.is_positive());
     assert!(!big_integer.is_negative());
@@ -116,18 +114,6 @@ fn small_integer() {
     check(&buffer, big_integer);
 }
 
-#[test]
-fn small_integer_negative() {
-    let buffer = [0x02, 0x01, 0xF9];
-    let big_integer = IntegerAsn1::from((-7).to_bigint().unwrap().to_signed_bytes_be());
-
-    assert!(!big_integer.is_positive());
-    assert!(big_integer.is_negative());
-    assert_eq!(big_integer.as_unsigned_bytes_be(), &[0xF9]);
-
-    check(&buffer, big_integer);
-}
-
 #[test]
 fn date() {
     let buffer = [
@@ -225,13 +211,6 @@ fn sequence_of() {
     check(&buffer, set_of_elems);
 }
 
-#[test]
-fn application_tag0() {
-    let buffer = [0xA0, 0x03, 0x02, 0x01, 0xF9];
-    let application_tag = ExplicitContextTag0(IntegerAsn1::from((-7).to_bigint().unwrap().to_signed_bytes_be()));
-    check(&buffer, application_tag);
-}
-
 #[test]
 fn restricted_strings() {
     let printable_string_buffer = b"\x13\x02\x4E\x4C";