From 31dd8471b5bfe9c3335d971267e7f29b06502b12 Mon Sep 17 00:00:00 2001
From: Nick Steel <nick@nsteel.co.uk>
Date: Fri, 30 Jun 2023 22:55:45 +0100
Subject: [PATCH] core: Obtain spclient access token using login5 instead of
 keymaster (Fixes #1179)

---
 core/src/spclient.rs | 93 +++++++++++++++++++++++++++++++++++++++++---
 protocol/build.rs    |  7 ++++
 2 files changed, 95 insertions(+), 5 deletions(-)

diff --git a/core/src/spclient.rs b/core/src/spclient.rs
index 156cf9c82..d0113535e 100644
--- a/core/src/spclient.rs
+++ b/core/src/spclient.rs
@@ -33,6 +33,7 @@ use crate::{
         },
         connect::PutStateRequest,
         extended_metadata::BatchedEntityRequest,
+        login5::{LoginRequest, LoginResponse},
     },
     token::Token,
     version::spotify_semantic_version,
@@ -44,6 +45,7 @@ component! {
         accesspoint: Option<SocketAddress> = None,
         strategy: RequestStrategy = RequestStrategy::default(),
         client_token: Option<Token> = None,
+        auth_token: Option<Token> = None,
     }
 }
 
@@ -149,6 +151,91 @@ impl SpClient {
         Ok(())
     }
 
+    async fn auth_token_request<M: Message>(&self, message: &M) -> Result<Bytes, Error> {
+        let client_token = self.client_token().await?;
+        let body = message.write_to_bytes()?;
+
+        let request = Request::builder()
+            .method(&Method::POST)
+            .uri("https://login5.spotify.com/v3/login")
+            .header(ACCEPT, HeaderValue::from_static("application/x-protobuf"))
+            .header(CLIENT_TOKEN, HeaderValue::from_str(&client_token)?)
+            .body(body.into())?;
+
+        self.session().http_client().request_body(request).await
+    }
+
+    pub async fn auth_token(&self) -> Result<Token, Error> {
+        let auth_token = self.lock(|inner| {
+            if let Some(token) = &inner.auth_token {
+                if token.is_expired() {
+                    inner.auth_token = None;
+                }
+            }
+            inner.auth_token.clone()
+        });
+
+        if let Some(auth_token) = auth_token {
+            return Ok(auth_token);
+        }
+
+        let client_id = match OS {
+            "macos" | "windows" => self.session().client_id(),
+            _ => SessionConfig::default().client_id,
+        };
+
+        let mut login_request = LoginRequest::new();
+        login_request.client_info.mut_or_insert_default().client_id = client_id;
+        login_request.client_info.mut_or_insert_default().device_id =
+            self.session().device_id().to_string();
+
+        let stored_credential = login_request.mut_stored_credential();
+        stored_credential.username = self.session().username().to_string();
+        stored_credential.data = self.session().auth_data().clone();
+
+        let mut response = self.auth_token_request(&login_request).await?;
+        let mut count = 0;
+        const MAX_TRIES: u8 = 3;
+
+        let token_response = loop {
+            count += 1;
+
+            let message = LoginResponse::parse_from_bytes(&response)?;
+            // TODO: Handle hash cash stuff
+            if message.has_ok() {
+                break message.ok().to_owned();
+            }
+
+            if count < MAX_TRIES {
+                response = self.auth_token_request(&login_request).await?;
+            } else {
+                return Err(Error::failed_precondition(format!(
+                    "Unable to solve any of {MAX_TRIES} hash cash challenges"
+                )));
+            }
+        };
+
+        let auth_token = Token {
+            access_token: token_response.access_token.clone(),
+            expires_in: Duration::from_secs(
+                token_response
+                    .access_token_expires_in
+                    .try_into()
+                    .unwrap_or(3600),
+            ),
+            token_type: "Bearer".to_string(),
+            scopes: vec![],
+            timestamp: Instant::now(),
+        };
+        self.lock(|inner| {
+            inner.auth_token = Some(auth_token.clone());
+        });
+
+        trace!("Got auth token: {:?}", auth_token);
+
+        Ok(auth_token)
+    }
+
     async fn client_token_request<M: Message>(&self, message: &M) -> Result<Bytes, Error> {
         let body = message.write_to_bytes()?;
 
@@ -468,11 +555,7 @@ impl SpClient {
                 .body(body.to_owned().into())?;
 
             // Reconnection logic: keep getting (cached) tokens because they might have expired.
-            let token = self
-                .session()
-                .token_provider()
-                .get_token("playlist-read")
-                .await?;
+            let token = self.auth_token().await?;
 
             let headers_mut = request.headers_mut();
             if let Some(ref hdrs) = headers {
diff --git a/protocol/build.rs b/protocol/build.rs
index e1378d378..8a0a8138b 100644
--- a/protocol/build.rs
+++ b/protocol/build.rs
@@ -28,6 +28,13 @@ fn compile() {
         proto_dir.join("playlist_permission.proto"),
         proto_dir.join("playlist4_external.proto"),
         proto_dir.join("spotify/clienttoken/v0/clienttoken_http.proto"),
+        proto_dir.join("spotify/login5/v3/challenges/code.proto"),
+        proto_dir.join("spotify/login5/v3/challenges/hashcash.proto"),
+        proto_dir.join("spotify/login5/v3/client_info.proto"),
+        proto_dir.join("spotify/login5/v3/credentials/credentials.proto"),
+        proto_dir.join("spotify/login5/v3/identifiers/identifiers.proto"),
+        proto_dir.join("spotify/login5/v3/login5.proto"),
+        proto_dir.join("spotify/login5/v3/user_info.proto"),
         proto_dir.join("storage-resolve.proto"),
         proto_dir.join("user_attributes.proto"),
         // TODO: remove these legacy protobufs when we are on the new API completely