From 096ccec741cc63cf3b9d4e6e230599c5c00274bc Mon Sep 17 00:00:00 2001
From: Jacob Kiers <code@kiers.eu>
Date: Thu, 29 Feb 2024 19:20:24 +0100
Subject: [PATCH] Use crate rsa instead of openssl

The rsa crate contains a pure rust implementation of the same
primitives.

This helps with cross platform support, such as Windows.

Signed-off-by: Jacob Kiers <code@kiers.eu>
---
 Cargo.toml | 11 ++++++-----
 src/lib.rs | 48 ++++++++++++++++++++++++++++--------------------
 2 files changed, 34 insertions(+), 25 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 44cb907..835813f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,10 +11,11 @@ edition = "2018"
 
 [dependencies]
 anyhow = "1.0.32"
-isahc = { version = "0.9.8", features = ["json"] }
-dotenv = "0.15.0"
-openssl = "0.10.30"
-serde_json = "1.0.57"
-serde = { version = "1.0.116", features = ["derive"] }
 base64 = "0.12.3"
 confy = "0.4.0"
+dotenv = "0.15.0"
+isahc = { version = "0.9.8", features = ["json"] }
+rand = "0.8.5"
+rsa = { version = "0.9.6", features = ["sha2"] }
+serde = { version = "1.0.116", features = ["derive"] }
+serde_json = "1.0.57"
diff --git a/src/lib.rs b/src/lib.rs
index 0d705ef..a72d2bd 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,9 +1,12 @@
-use anyhow::Result;
+use anyhow::{anyhow, Result};
+use isahc::http::StatusCode;
 use isahc::prelude::*;
-use openssl::hash::MessageDigest;
-use openssl::pkey::PKey;
-use openssl::rsa::Rsa;
-use openssl::sign::Signer;
+use rsa::pkcs1::{DecodeRsaPrivateKey, EncodeRsaPrivateKey};
+use rsa::RsaPrivateKey;
+use rsa::pkcs1v15::SigningKey;
+use rsa::pkcs8::{EncodePublicKey, LineEnding};
+use rsa::signature::RandomizedSigner;
+use rsa::sha2::Sha256;
 use serde::{de::DeserializeOwned, Deserialize, Serialize};
 
 const BASE: &str = "https://api.bunq.com";
@@ -47,12 +50,11 @@ struct UserPerson {
     id: i64,
 }
 
-fn sign<K: openssl::pkey::HasPrivate>(body: &str, key: &PKey<K>) -> Result<String> {
-    let mut signer = Signer::new(MessageDigest::sha256(), key)?;
-
-    let sig = signer.sign_oneshot_to_vec(body.as_bytes())?;
-
-    Ok(base64::encode(&sig))
+fn sign(body: &str, key: &RsaPrivateKey) -> Result<String> {
+    let signing_key = SigningKey::<Sha256>::new(key.clone());
+    let mut rng = rand::thread_rng();
+    let signature = signing_key.sign_with_rng(&mut rng, body.as_bytes());
+    Ok(base64::encode(signature.to_string()))
 }
 
 #[derive(Deserialize)]
@@ -111,7 +113,7 @@ pub struct BunqConfig {
 }
 pub struct BunqConfigReady {
     token: String,
-    keypair: PKey<openssl::pkey::Private>,
+    keypair: RsaPrivateKey,
     user_id: i64,
 }
 impl BunqConfig {
@@ -126,15 +128,14 @@ impl BunqConfig {
         let api_key = &self.api_key;
 
         let keypair = if let Some(state) = &self.state {
-            PKey::private_key_from_pem(state.pem_private.as_bytes())?
+            RsaPrivateKey::from_pkcs1_pem(&*state.pem_private)?
         } else {
-            let rsa = Rsa::generate(2048)?;
-            let pem_private = rsa.private_key_to_pem()?;
-            let pem_private = String::from_utf8(pem_private)?;
+            let mut rng = rand::thread_rng();
 
-            let keypair = PKey::from_rsa(rsa)?;
+            let bits = 2048;
+            let keypair = RsaPrivateKey::new(&mut rng, bits).expect("failed to generate a key");
 
-            let pem_public = String::from_utf8(keypair.public_key_to_pem()?)?;
+            let pem_public = keypair.to_public_key().to_public_key_pem(LineEnding::CRLF)?;
 
             let body = Installation {
                 client_public_key: &pem_public,
@@ -157,9 +158,15 @@ impl BunqConfig {
                 .header("X-Bunq-Client-Authentication", &token)
                 .body(body)?
                 .send()?;
-            println!("{}", response.text()?);
 
-            self.state = Some(AppState { pem_private, token });
+            let response_text = response.text()?;
+            println!("{}", response_text);
+
+            if response.status() != StatusCode::OK {
+                return Err(anyhow!(response_text));
+            }
+
+            self.state = Some(AppState { pem_private: keypair.to_pkcs1_pem(LineEnding::CRLF)?.to_string(), token });
             self.save()?;
 
             keypair
@@ -175,6 +182,7 @@ impl BunqConfig {
             .send()?
             .text()?;
         let r: SessionServerResponse = deserialize_retarded_response(&response)?.response;
+
         Ok(BunqConfigReady {
             keypair,
             token: r.token.token,