Fix Cashu file redemption and Bitcoin-dependent wallet readiness

core/archipelago/src/wallet/payment_tests.rs

@@ -0,0 +1,428 @@
+//! Real HTTP/curve-signature regressions for paid Cashu redemption.
+use super::*;
+use crate::wallet::{bdhke, cashu::Proof};
+use bitcoin::secp256k1::{PublicKey, Scalar, Secp256k1, SecretKey};
+use hyper::{
+    service::{make_service_fn, service_fn},
+    Body, Request, Response, Server,
+};
+use serde_json::{json, Value};
+use std::{
+    convert::Infallible,
+    sync::{Arc, Mutex},
+};
+
+const ACTIVE: &str = "0011223344556677";
+const V2: &str = "011111111111111111111111111111111111111111111111111111111111111111";
+
+struct Mint {
+    url: String,
+    requests: Arc<Mutex<Vec<Value>>>,
+    task: tokio::task::JoinHandle<()>,
+    failure: Arc<std::sync::atomic::AtomicU16>,
+}
+impl Drop for Mint {
+    fn drop(&mut self) {
+        self.task.abort();
+    }
+}
+
+fn signing_key() -> SecretKey {
+    SecretKey::from_slice(&[7; 32]).unwrap()
+}
+fn signed_point(point: PublicKey) -> String {
+    point
+        .mul_tweak(&Secp256k1::new(), &Scalar::from(signing_key()))
+        .unwrap()
+        .to_string()
+}
+fn proof(id: &str, amount: u64) -> Proof {
+    let secret = format!("test-{id}-{amount}");
+    Proof {
+        amount,
+        id: id.into(),
+        c: signed_point(bdhke::hash_to_curve(secret.as_bytes()).unwrap()),
+        secret,
+    }
+}
+impl Mint {
+    async fn start(fee: u64, failure: Option<u16>) -> Self {
+        let listener = std::net::TcpListener::bind("127.0.0.1:0").unwrap();
+        listener.set_nonblocking(true).unwrap();
+        let url = format!("http://{}", listener.local_addr().unwrap());
+        let requests = Arc::new(Mutex::new(Vec::new()));
+        let seen = requests.clone();
+        let failure = Arc::new(std::sync::atomic::AtomicU16::new(failure.unwrap_or(0)));
+        let rejection = failure.clone();
+        let spent = Arc::new(Mutex::new(std::collections::HashSet::<String>::new()));
+        let service = make_service_fn(move |_| {
+            let seen = seen.clone();
+            let rejection = rejection.clone();
+            let spent = spent.clone();
+            async move {
+                Ok::<_, Infallible>(service_fn(move |req: Request<Body>| {
+                    let seen = seen.clone();
+                    let rejection = rejection.clone();
+                    let spent = spent.clone();
+                    async move {
+                        let mut status = 200;
+                        let body = match req.uri().path() {
+                            "/v1/keysets" => json!({"keysets":[
+                                {"id": ACTIVE,"unit":"sat","active":true,"input_fee_ppk":fee},
+                                {"id": V2,"unit":"sat","active":false,"input_fee_ppk":fee}
+                            ]}),
+                            "/v1/keys" => {
+                                let public =
+                                    PublicKey::from_secret_key(&Secp256k1::new(), &signing_key())
+                                        .to_string();
+                                let keys: serde_json::Map<String, Value> = (0..16)
+                                    .map(|i| ((1u64 << i).to_string(), json!(public)))
+                                    .collect();
+                                json!({"keysets":[{"id": ACTIVE,"unit":"sat","keys":keys}]})
+                            }
+                            "/v1/swap" => {
+                                let body: Value = serde_json::from_slice(
+                                    &hyper::body::to_bytes(req.into_body()).await.unwrap(),
+                                )
+                                .unwrap();
+                                seen.lock().unwrap().push(body.clone());
+                                let inputs = body["inputs"].as_array().unwrap();
+                                let outputs = body["outputs"].as_array().unwrap();
+                                let code = rejection.load(std::sync::atomic::Ordering::SeqCst);
+                                if code != 0 {
+                                    status = code;
+                                    json!({"detail":"mock mint rejection"})
+                                } else if inputs.iter().any(|p| p["id"] != V2 && p["id"] != ACTIVE)
+                                {
+                                    status = 422;
+                                    json!({"detail":[{"msg":"NUT02: ID length invalid"}]})
+                                } else if inputs.iter().any(|p| {
+                                    spent
+                                        .lock()
+                                        .unwrap()
+                                        .contains(p["secret"].as_str().unwrap())
+                                }) {
+                                    status = 400;
+                                    json!({"code":11001,"detail":"Token Already Spent"})
+                                } else {
+                                    let total: u64 =
+                                        inputs.iter().map(|p| p["amount"].as_u64().unwrap()).sum();
+                                    let out: u64 =
+                                        outputs.iter().map(|p| p["amount"].as_u64().unwrap()).sum();
+                                    assert_eq!(
+                                        out,
+                                        total - (inputs.len() as u64 * fee).div_ceil(1000)
+                                    );
+                                    for p in inputs {
+                                        spent
+                                            .lock()
+                                            .unwrap()
+                                            .insert(p["secret"].as_str().unwrap().into());
+                                    }
+                                    json!({"signatures":outputs.iter().map(|o| json!({
+                                    "amount":o["amount"],"id":ACTIVE,
+                                    "C_":signed_point(o["B_"].as_str().unwrap().parse().unwrap())
+                                })).collect::<Vec<_>>()})
+                                }
+                            }
+                            _ => {
+                                status = 404;
+                                json!({})
+                            }
+                        };
+                        Ok::<_, Infallible>(
+                            Response::builder()
+                                .status(status)
+                                .header("Content-Type", "application/json")
+                                .body(Body::from(body.to_string()))
+                                .unwrap(),
+                        )
+                    }
+                }))
+            }
+        });
+        let server = Server::from_tcp(listener).unwrap().serve(service);
+        let task = tokio::spawn(async move {
+            server.await.unwrap();
+        });
+        Self {
+            url,
+            requests,
+            task,
+            failure,
+        }
+    }
+    async fn wallet(&self) -> tempfile::TempDir {
+        let dir = tempfile::tempdir().unwrap();
+        save_accepted_mints(
+            dir.path(),
+            &AcceptedMints {
+                mints: vec![format!("{}/", self.url)],
+            },
+        )
+        .await
+        .unwrap();
+        dir
+    }
+}
+
+#[tokio::test]
+async fn paid_v4_inactive_v2_keyset_is_expanded_and_cryptographic_proofs_saved() {
+    let mint = Mint::start(0, None).await;
+    let dir = mint.wallet().await;
+    let token = CashuToken::new(&mint.url, vec![proof(V2, 64), proof(V2, 32), proof(V2, 4)])
+        .serialize_v4()
+        .unwrap();
+    let decoded = CashuToken::deserialize(&token).unwrap();
+    assert_eq!(
+        decoded.token[0].proofs[0].id.len(),
+        16,
+        "reproduce the short V4 ID"
+    );
+    assert_eq!(
+        verify_and_receive_payment(dir.path(), &token, 100)
+            .await
+            .unwrap(),
+        100
+    );
+    let wallet = load_wallet(dir.path()).await.unwrap();
+    assert_eq!(wallet.balance(), 100);
+    for p in wallet.proofs {
+        assert_eq!(
+            p.proof.c,
+            signed_point(bdhke::hash_to_curve(p.proof.secret.as_bytes()).unwrap())
+        );
+    }
+    assert!(mint.requests.lock().unwrap()[0]["inputs"]
+        .as_array()
+        .unwrap()
+        .iter()
+        .all(|p| p["id"] == V2));
+    assert!(verify_and_receive_payment(dir.path(), &token, 100)
+        .await
+        .is_err());
+    assert_eq!(load_wallet(dir.path()).await.unwrap().balance(), 100);
+}
+
+#[tokio::test]
+async fn paid_v3_full_v2_and_v1_ids_work() {
+    for id in [V2, ACTIVE] {
+        let mint = Mint::start(0, None).await;
+        let dir = mint.wallet().await;
+        let token = CashuToken::new(&mint.url, vec![proof(id, 128)])
+            .serialize()
+            .unwrap();
+        assert_eq!(
+            verify_and_receive_payment(dir.path(), &token, 100)
+                .await
+                .unwrap(),
+            128
+        );
+    }
+}
+
+#[tokio::test]
+async fn fees_cannot_consume_underpayment_and_allowed_fees_credit_actual_value() {
+    let mint = Mint::start(1000, None).await;
+    let dir = mint.wallet().await;
+    let token = CashuToken::new(&mint.url, vec![proof(V2, 128)])
+        .serialize_v4()
+        .unwrap();
+    assert!(verify_and_receive_payment(dir.path(), &token, 128)
+        .await
+        .unwrap_err()
+        .to_string()
+        .contains("after mint fees"));
+    assert!(mint.requests.lock().unwrap().is_empty());
+    assert_eq!(
+        verify_and_receive_payment(dir.path(), &token, 127)
+            .await
+            .unwrap(),
+        127
+    );
+    assert_eq!(load_wallet(dir.path()).await.unwrap().balance(), 127);
+}
+
+#[tokio::test]
+async fn rejected_mint_response_does_not_credit_wallet() {
+    for status in [200, 400, 422, 500, 503] {
+        let mint = Mint::start(0, Some(status)).await;
+        let dir = mint.wallet().await;
+        let token = CashuToken::new(&mint.url, vec![proof(V2, 128)])
+            .serialize_v4()
+            .unwrap();
+        assert!(verify_and_receive_payment(dir.path(), &token, 100)
+            .await
+            .is_err());
+        assert_eq!(load_wallet(dir.path()).await.unwrap().balance(), 0);
+    }
+}
+
+#[tokio::test]
+async fn invalid_untrusted_multimint_and_underpaid_tokens_never_reach_swap() {
+    let mint = Mint::start(0, None).await;
+    let dir = mint.wallet().await;
+    let token = CashuToken::new(&mint.url, vec![proof(V2, 128)]);
+    let mut invalid = vec![
+        "cashuSend_500_abc_1700000000".into(),
+        "cashuBinvalid".into(),
+    ];
+    let mut wrong_unit = token.clone();
+    wrong_unit.unit = Some("usd".into());
+    invalid.push(wrong_unit.serialize().unwrap());
+    let mut multi = token.clone();
+    multi.token.push(token.token[0].clone());
+    invalid.push(multi.serialize().unwrap());
+    let mut untrusted = token.clone();
+    untrusted.token[0].mint = "http://127.0.0.1:1".into();
+    invalid.push(untrusted.serialize().unwrap());
+    for id in ["00ffffffffffffff", "01ffffffffffffff"] {
+        invalid.push(
+            CashuToken::new(&mint.url, vec![proof(id, 128)])
+                .serialize()
+                .unwrap(),
+        );
+    }
+    for value in invalid {
+        assert!(verify_and_receive_payment(dir.path(), &value, 100)
+            .await
+            .is_err());
+    }
+    assert!(
+        verify_and_receive_payment(dir.path(), &token.serialize().unwrap(), 129)
+            .await
+            .is_err()
+    );
+    assert!(mint.requests.lock().unwrap().is_empty());
+    assert_eq!(load_wallet(dir.path()).await.unwrap().balance(), 0);
+}
+
+#[tokio::test]
+async fn buyer_token_rejected_by_seller_can_be_refunded_without_balance_loss() {
+    let mint = Mint::start(0, Some(422)).await;
+    let buyer = mint.wallet().await;
+    let seller = mint.wallet().await;
+    let mut wallet = load_wallet(buyer.path()).await.unwrap();
+    wallet.mint_url = mint.url.clone();
+    wallet.add_proofs(&mint.url, vec![proof(V2, 64), proof(V2, 32), proof(V2, 4)]);
+    save_wallet(buyer.path(), &wallet).await.unwrap();
+    let token = send_token(buyer.path(), 100).await.unwrap();
+    assert_eq!(load_wallet(buyer.path()).await.unwrap().balance(), 0);
+    assert!(verify_and_receive_payment(seller.path(), &token, 100)
+        .await
+        .is_err());
+    mint.failure.store(0, std::sync::atomic::Ordering::SeqCst);
+    assert_eq!(receive_token(buyer.path(), &token).await.unwrap(), 100);
+    assert_eq!(load_wallet(buyer.path()).await.unwrap().balance(), 100);
+    assert_eq!(load_wallet(seller.path()).await.unwrap().balance(), 0);
+    assert!(receive_token(buyer.path(), &token).await.is_err());
+    assert_eq!(load_wallet(buyer.path()).await.unwrap().balance(), 100);
+}
+
+#[tokio::test]
+async fn unreachable_mint_does_not_credit_seller() {
+    let mint = Mint::start(0, None).await;
+    let dir = mint.wallet().await;
+    let token = CashuToken::new(&mint.url, vec![proof(V2, 128)])
+        .serialize_v4()
+        .unwrap();
+    mint.task.abort();
+    tokio::task::yield_now().await;
+    assert!(verify_and_receive_payment(dir.path(), &token, 100)
+        .await
+        .is_err());
+    assert_eq!(load_wallet(dir.path()).await.unwrap().balance(), 0);
+}
+
+#[tokio::test]
+async fn send_with_fees_preserves_payment_denominations_and_saves_change() {
+    // 128 inputs - 2 fee = 126. Splitting 126 as one sum omits 1,
+    // which is needed for a 65-sat payment, after consuming the inputs.
+    let mint = Mint::start(1000, None).await;
+    let buyer = mint.wallet().await;
+    let mut wallet = load_wallet(buyer.path()).await.unwrap();
+    wallet.mint_url = mint.url.clone();
+    let first = proof(V2, 64);
+    let mut second = first.clone();
+    second.secret.push_str("-second");
+    second.c = signed_point(bdhke::hash_to_curve(second.secret.as_bytes()).unwrap());
+    wallet.add_proofs(&mint.url, vec![first, second]);
+    save_wallet(buyer.path(), &wallet).await.unwrap();
+    let encoded = send_token(buyer.path(), 65).await.unwrap();
+    assert_eq!(
+        CashuToken::deserialize(&encoded).unwrap().total_amount(),
+        65
+    );
+    assert_eq!(load_wallet(buyer.path()).await.unwrap().balance(), 61);
+}
+
+#[tokio::test]
+async fn paid_file_gate_delivers_bytes_only_after_payment_and_does_not_charge_missing_files() {
+    use crate::content_server::{
+        self, AccessControl, Availability, ContentCatalog, ContentItem, ServeResult,
+    };
+    for (exists, accepts_cashu, price) in [
+        (true, true, 100),
+        (true, false, 100),
+        (false, true, 100),
+        (true, true, 129),
+    ] {
+        let mint = Mint::start(0, None).await;
+        let seller = mint.wallet().await;
+        let item = ContentItem {
+            id: "paid-test".into(),
+            filename: "test.txt".into(),
+            mime_type: "text/plain".into(),
+            size_bytes: 5,
+            description: String::new(),
+            added_at: String::new(),
+            availability: Availability::AllPeers,
+            access: AccessControl::Paid {
+                price_sats: price,
+                accepted: vec![if accepts_cashu { "ecash" } else { "fedimint" }.into()],
+            },
+        };
+        content_server::save_catalog(seller.path(), &ContentCatalog { items: vec![item] })
+            .await
+            .unwrap();
+        if exists {
+            tokio::fs::create_dir_all(seller.path().join("content/files"))
+                .await
+                .unwrap();
+            tokio::fs::write(seller.path().join("content/files/test.txt"), b"hello")
+                .await
+                .unwrap();
+        }
+        let token = CashuToken::new(&mint.url, vec![proof(V2, 128)])
+            .serialize_v4()
+            .unwrap();
+        let result = content_server::serve_content(
+            seller.path(),
+            "paid-test",
+            Some(&token),
+            None,
+            None,
+            None,
+            false,
+        )
+        .await
+        .unwrap();
+        if exists && accepts_cashu && price <= 128 {
+            match result {
+                ServeResult::Ok(bytes, mime) => {
+                    assert_eq!(bytes, b"hello");
+                    assert_eq!(mime, "text/plain");
+                }
+                _ => panic!("paid content was not delivered"),
+            }
+            assert_eq!(load_wallet(seller.path()).await.unwrap().balance(), 128);
+        } else {
+            assert!(matches!(
+                result,
+                ServeResult::NotFound | ServeResult::PaymentRequired(_)
+            ));
+            assert_eq!(load_wallet(seller.path()).await.unwrap().balance(), 0);
+            assert!(mint.requests.lock().unwrap().is_empty());
+        }
+    }
+}