Add settings migration code, refactor and cleanup

Bump the settings version. Add code for migrating settings to new
version since it is now not backwards compatible.
Refactor LocationConstraint and related types to be more lean.
Cleanup issues and fix formatting.
Refactor LocationConstraint and add migration code

2 files changed, 296 insertions, 11 deletions

diff --git a/mullvad-daemon/src/migrations/v6.rs b/mullvad-daemon/src/migrations/v6.rs
index 54dc2268e4..3a842923f0 100644
--- a/mullvad-daemon/src/migrations/v6.rs
+++ b/mullvad-daemon/src/migrations/v6.rs
@@ -36,16 +36,55 @@ pub fn migrate(settings: &mut serde_json::Value) -> Result<()> {
 
     migrate_udp2tcp_port_443(settings);
 
-    // TODO
-    // log::info!("Migrating settings format to V7");
+    migrate_location_constraint(settings)?;
 
-    // Note: Not incrementing the version number yet, since this migration is still open
-    // for future modification.
-    // settings["settings_version"] = serde_json::json!(SettingsVersion::V7);
+    log::info!("Migrating settings format to V7");
+
+    settings["settings_version"] = serde_json::json!(SettingsVersion::V7);
+
+    Ok(())
+}
+
+fn migrate_location_constraint(settings: &mut serde_json::Value) -> Result<()> {
+    if let Some(location) = settings
+        .get_mut("relay_settings")
+        .and_then(|relay_settings| relay_settings.get_mut("normal"))
+        .and_then(|normal_relay_settings| normal_relay_settings.get_mut("location"))
+    {
+        wrap_location(location)?;
+    }
+
+    if let Some(location) = settings
+        .get_mut("relay_settings")
+        .and_then(|relay_settings| relay_settings.get_mut("normal"))
+        .and_then(|normal_relay_settings| normal_relay_settings.get_mut("wireguard_constraints"))
+        .and_then(|normal_relay_settings| normal_relay_settings.get_mut("entry_location"))
+    {
+        wrap_location(location)?;
+    }
+
+    if let Some(location) = settings
+        .get_mut("bridge_settings")
+        .and_then(|relay_settings| relay_settings.get_mut("normal"))
+        .and_then(|normal_relay_settings| normal_relay_settings.get_mut("location"))
+    {
+        wrap_location(location)?;
+    }
 
     Ok(())
 }
 
+fn wrap_location(location: &mut serde_json::Value) -> Result<()> {
+    if let Some(only) = location.get_mut("only") {
+        only["location"] = only.clone();
+        let only = only.as_object_mut().ok_or(Error::InvalidSettingsContent)?;
+        only.remove("country");
+        only.remove("city");
+        only.remove("hostname");
+    }
+    Ok(())
+}
+
 fn migrate_pq_setting(settings: &mut serde_json::Value) -> Result<()> {
     if let Some(tunnel_options) = settings
         .get_mut("tunnel_options")
@@ -89,7 +128,7 @@ fn version_matches(settings: &mut serde_json::Value) -> bool {
 
 #[cfg(test)]
 mod test {
-    use super::{migrate, migrate_pq_setting, version_matches};
+    use super::{migrate, migrate_location_constraint, migrate_pq_setting, version_matches};
 
     pub const V6_SETTINGS: &str = r#"
 {
@@ -175,7 +214,9 @@ mod test {
     "normal": {
       "location": {
         "only": {
-          "country": "se"
+          "location": {
+            "country": "se"
+          }
         }
       },
       "tunnel_protocol": "any",
@@ -241,7 +282,7 @@ mod test {
       }
     }
   },
-  "settings_version": 6
+  "settings_version": 7
 }
 "#;
 
@@ -256,6 +297,252 @@ mod test {
         assert_eq!(&old_settings, &new_settings);
     }
 
+    /// For relay settings
+    /// location: { only: { country : "se" } } should be replaced with
+    /// location: { only: { location: { country: "se" } } }
+    #[test]
+    fn test_from_relay_settings_location_constraint_country() {
+        let mut migrated_settings: serde_json::Value = serde_json::from_str(
+            r#"
+        {
+            "relay_settings": {
+                "normal": {
+                    "location": {
+                        "only": {
+                            "country": "se"
+                        }
+                    }
+                }
+            }
+        }
+        "#,
+        )
+        .unwrap();
+        migrate_location_constraint(&mut migrated_settings).unwrap();
+
+        let expected_settings: serde_json::Value = serde_json::from_str(
+            r#"
+        {
+            "relay_settings": {
+                "normal": {
+                    "location": {
+                        "only": {
+                            "location": {
+                                "country": "se"
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        "#,
+        )
+        .unwrap();
+
+        assert_eq!(migrated_settings, expected_settings);
+    }
+
+    /// For relay settings
+    /// location: { only: { country : "se", city: "got" } } should be replaced with
+    /// location: { only: { location: { country: "se", city: "got" } } }
+    #[test]
+    fn test_from_relay_settings_location_constraint_city() {
+        let mut migrated_settings: serde_json::Value = serde_json::from_str(
+            r#"
+        {
+            "relay_settings": {
+                "normal": {
+                    "location": {
+                        "only": {
+                            "country": "se",
+                            "city": "got"
+                        }
+                    }
+                }
+            }
+        }
+        "#,
+        )
+        .unwrap();
+        migrate_location_constraint(&mut migrated_settings).unwrap();
+
+        let expected_settings: serde_json::Value = serde_json::from_str(
+            r#"
+        {
+            "relay_settings": {
+                "normal": {
+                    "location": {
+                        "only": {
+                            "location": {
+                                "country": "se",
+                                "city": "got"
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        "#,
+        )
+        .unwrap();
+
+        assert_eq!(migrated_settings, expected_settings);
+    }
+
+    /// For relay settings
+    /// location: { only: { country : "se", city: "got", hostname: "se-got-wg-001" } } should be
+    /// replaced with location: { only: { location: { country: "se", city: "got", hostname:
+    /// "se-got-wg-001" } } }
+    #[test]
+    fn test_from_relay_settings_location_constraint_hostname() {
+        let mut migrated_settings: serde_json::Value = serde_json::from_str(
+            r#"
+        {
+            "relay_settings": {
+                "normal": {
+                    "location": {
+                        "only": {
+                            "country": "se",
+                            "city": "got",
+                            "hostname": "se-got-wg-001"
+                        }
+                    }
+                }
+            }
+        }
+        "#,
+        )
+        .unwrap();
+        migrate_location_constraint(&mut migrated_settings).unwrap();
+
+        let expected_settings: serde_json::Value = serde_json::from_str(
+            r#"
+        {
+            "relay_settings": {
+                "normal": {
+                    "location": {
+                        "only": {
+                            "location": {
+                                "country": "se",
+                                "city": "got",
+                                "hostname": "se-got-wg-001"
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        "#,
+        )
+        .unwrap();
+
+        assert_eq!(migrated_settings, expected_settings);
+    }
+
+    /// For bridge settings
+    /// location: { only: { country : "se", city: "got", hostname: "se-got-wg-001" } } should be
+    /// replaced with location: { only: { location: { country: "se", city: "got", hostname:
+    /// "se-got-wg-001" } } }
+    #[test]
+    fn test_from_bridge_location_constraint_hostname() {
+        let mut migrated_settings: serde_json::Value = serde_json::from_str(
+            r#"
+        {
+            "bridge_settings": {
+                "normal": {
+                    "location": {
+                        "only": {
+                            "country": "se",
+                            "city": "got",
+                            "hostname": "se-got-wg-001"
+                        }
+                    }
+                }
+            }
+        }
+        "#,
+        )
+        .unwrap();
+        migrate_location_constraint(&mut migrated_settings).unwrap();
+
+        let expected_settings: serde_json::Value = serde_json::from_str(
+            r#"
+        {
+            "bridge_settings": {
+                "normal": {
+                    "location": {
+                        "only": {
+                            "location": {
+                                "country": "se",
+                                "city": "got",
+                                "hostname": "se-got-wg-001"
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        "#,
+        )
+        .unwrap();
+
+        assert_eq!(migrated_settings, expected_settings);
+    }
+
+    /// For wireguard constraints
+    /// location: { only: { country : "se", city: "got", hostname: "se-got-wg-001" } } should be
+    /// replaced with location: { only: { location: { country: "se", city: "got", hostname:
+    /// "se-got-wg-001" } } }
+    #[test]
+    fn test_from_wireguard_constraint_location_constraint_hostname() {
+        let mut migrated_settings: serde_json::Value = serde_json::from_str(
+            r#"
+        {
+            "relay_settings": {
+                "normal": {
+                    "wireguard_constraints": {
+                        "entry_location": {
+                            "only": {
+                                "country": "se",
+                                "city": "got",
+                                "hostname": "se-got-wg-001"
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        "#,
+        )
+        .unwrap();
+        migrate_location_constraint(&mut migrated_settings).unwrap();
+
+        let expected_settings: serde_json::Value = serde_json::from_str(
+            r#"
+        {
+            "relay_settings": {
+                "normal": {
+                    "wireguard_constraints": {
+                        "entry_location": {
+                            "only": {
+                                "location": {
+                                    "country": "se",
+                                    "city": "got",
+                                    "hostname": "se-got-wg-001"
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        "#,
+        )
+        .unwrap();
+
+        assert_eq!(migrated_settings, expected_settings);
+    }
+
     /// use_pq_safe_psk=false should be replaced with quantum_resistant=null
     #[test]
     fn test_from_pq_safe_psk_false() {
diff --git a/mullvad-daemon/src/settings.rs b/mullvad-daemon/src/settings.rs
index ee3f355598..794b0381ca 100644
--- a/mullvad-daemon/src/settings.rs
+++ b/mullvad-daemon/src/settings.rs
@@ -378,9 +378,7 @@ mod test {
                   "location": {
                     "only": {
                       "location": {
-                        "location": {
-                          "country": "gb"
-                        }
+                        "country": "gb"
                       }
                     }
                   },