matc/device/
persist.rs

1use std::collections::{HashMap, HashSet};
2use std::sync::Arc;
3use std::sync::atomic::AtomicU32;
4
5use anyhow::{Context, Result};
6
7use crate::fabric;
8
9use super::Device;
10use super::types::{AttributeOverride, DeviceConfig, FabricInfo, PersistedDeviceState, PersistedFabricState};
11
12static PERSISTED_ATTRIBUTES: &[(u16, u32, u32)] = &[];
13
14impl Device {
15    pub(crate) fn collect_attribute_overrides(&self) -> Vec<AttributeOverride> {
16        let mut overrides = Vec::new();
17        for &(endpoint, cluster, attribute) in PERSISTED_ATTRIBUTES.iter().chain(self.extra_persisted.iter()) {
18            if let Some(tlv) = self.attributes.get(&(endpoint, cluster, attribute)) {
19                overrides.push(AttributeOverride {
20                    endpoint,
21                    cluster,
22                    attribute,
23                    tlv_hex: hex::encode(tlv),
24                });
25            }
26        }
27        overrides
28    }
29
30    /// Register an additional attribute key to include in persistence.
31    pub fn add_persisted_attribute(&mut self, endpoint: u16, cluster: u32, attribute: u32) {
32        let key = (endpoint, cluster, attribute);
33        if !self.extra_persisted.contains(&key) {
34            self.extra_persisted.push(key);
35        }
36    }
37
38    /// Persist current commissioned state to `{state_dir}/device_state.json`.
39    pub(crate) fn save_state(&self, state_dir: &str) -> Result<()> {
40        if self.fabrics.is_empty() {
41            let path = format!("{}/device_state.json", state_dir);
42            if std::path::Path::new(&path).exists() {
43                std::fs::remove_file(&path)?;
44                log::info!("All fabrics removed - deleted {}", path);
45            }
46            return Ok(());
47        }
48
49        let fabrics: Vec<PersistedFabricState> = self
50            .fabrics
51            .iter()
52            .map(|fi| PersistedFabricState {
53                fabric_index: fi.fabric_index,
54                trusted_root_cert: fi.trusted_root_cert.clone(),
55                noc: fi.noc.clone(),
56                icac: fi.icac.clone(),
57                ipk: fi.ipk.clone(),
58                controller_id: fi.controller_id,
59                vendor_id: fi.vendor_id,
60                device_matter_cert: fi.device_matter_cert.clone(),
61                label: fi.label.clone(),
62            })
63            .collect();
64
65        let state = PersistedDeviceState {
66            operational_key_hex: hex::encode(self.operational_key.to_bytes()),
67            next_fabric_index: self.next_fabric_index,
68            fabrics,
69            attribute_overrides: self.collect_attribute_overrides(),
70        };
71
72        std::fs::create_dir_all(state_dir)?;
73        let path = format!("{}/device_state.json", state_dir);
74        let json = serde_json::to_string_pretty(&state)?;
75        std::fs::write(&path, json)?;
76        log::info!("Device state saved to {}", path);
77        Ok(())
78    }
79
80    /// Register the operational `_matter._tcp.local` mDNS service for one fabric.
81    /// `fabric_idx` is an index into `self.fabrics`.
82    pub(crate) async fn register_operational_mdns(&self, fabric_idx: usize) -> Result<()> {
83        let fi = &self.fabrics[fabric_idx];
84        let nod_id = fi.device_node_id()?;
85        let ca_public_key = fi.ca_public_key()?;
86        let fabric_id = fi.fabric_id()?;
87        let ca_id = fi.ca_id()?;
88        let fabric = fabric::Fabric::new(fabric_id, ca_id, &ca_public_key);
89
90        let iname = format!(
91            "{}-{:016X}",
92            hex::encode_upper(fabric.compressed()?),
93            nod_id
94        );
95        let op_port: u16 = self
96            .config
97            .listen_address
98            .rsplit(':')
99            .next()
100            .and_then(|p| p.parse().ok())
101            .unwrap_or(5540);
102        let (adv_v4, adv_v6) = self.config.split_advertise_ips();
103        let svc = crate::mdns2::ServiceRegistration {
104            instance_name: iname,
105            service_type: "_matter._tcp.local".to_string(),
106            port: op_port,
107            txt_records: vec![],
108            hostname: self.config.hostname.clone(),
109            ttl: 120,
110            subtypes: vec![],
111            ips_v4: adv_v4,
112            ips_v6: adv_v6,
113        };
114        self.mdns.register_service(svc).await;
115        Ok(())
116    }
117
118    /// Restore a previously commissioned device from `{state_dir}/device_state.json`.
119    ///
120    /// On success the device is ready to accept CASE sessions - it will NOT re-advertise
121    /// the commissionable `_matterc._udp` service.
122    pub async fn from_persisted_state(
123        config: DeviceConfig,
124        mdns: Arc<crate::mdns2::MdnsService>,
125        state_dir: &str,
126    ) -> Result<Self> {
127        let path = format!("{}/device_state.json", state_dir);
128        let json = std::fs::read_to_string(&path)
129            .with_context(|| format!("Cannot read persisted state from {}", path))?;
130        let state: PersistedDeviceState = serde_json::from_str(&json)?;
131
132        // Restore P-256 operational key from hex-encoded scalar bytes.
133        let key_bytes = hex::decode(&state.operational_key_hex)
134            .context("Invalid hex in operational_key_hex")?;
135        let operational_key = p256::SecretKey::from_slice(&key_bytes)
136            .context("Invalid P-256 scalar in persisted operational key")?;
137
138        let socket = tokio::net::UdpSocket::bind(&config.listen_address).await?;
139
140        let mut salt = vec![0u8; 32];
141        rand::RngCore::fill_bytes(&mut rand::thread_rng(), &mut salt);
142
143        let fabrics: Vec<FabricInfo> = state
144            .fabrics
145            .iter()
146            .map(|pf| FabricInfo {
147                fabric_index: pf.fabric_index,
148                ipk: pf.ipk.clone(),
149                fabric: None,
150                device_matter_cert: pf.device_matter_cert.clone(),
151                controller_id: pf.controller_id,
152                vendor_id: pf.vendor_id,
153                trusted_root_cert: pf.trusted_root_cert.clone(),
154                noc: pf.noc.clone(),
155                icac: pf.icac.clone(),
156                label: pf.label.clone(),
157            })
158            .collect();
159
160        let mut device = Self {
161            config,
162            socket,
163            salt,
164            pbkdf_iterations: 1000,
165            operational_key,
166            message_counter: AtomicU32::new(rand::random()),
167            pase_state: None,
168            pase_session: None,
169            case_states: HashMap::new(),
170            case_sessions: Vec::new(),
171            subscribe_states: Vec::new(),
172            active_subscriptions: Vec::new(),
173            pending_chunks: Vec::new(),
174            fabrics,
175            next_fabric_index: state.next_fabric_index,
176            pending_root_cert: None,
177            received_counters: HashSet::new(),
178            endpoints: vec![0],
179            attributes: HashMap::new(),
180            dirty_attributes: HashSet::new(),
181            mdns,
182            extra_persisted: Vec::new(),
183        };
184
185        device.setup_default_attributes()?;
186
187        // Overlay persisted attribute values on top of the defaults.
188        // Old JSON files may still contain Fabrics/CommissionedFabrics entries here;
189        // they are overwritten by rebuild_fabrics_attribute() below.
190        for ov in &state.attribute_overrides {
191            let tlv = hex::decode(&ov.tlv_hex)
192                .with_context(|| format!("Bad tlv_hex for ({},{},{})", ov.endpoint, ov.cluster, ov.attribute))?;
193            device.attributes.insert((ov.endpoint, ov.cluster, ov.attribute), tlv);
194        }
195
196        // Rebuild Fabrics and CommissionedFabrics from the restored fabric list.
197        device.rebuild_fabrics_attribute()?;
198        device.dirty_attributes.clear();
199
200        // Re-register operational mDNS for each fabric.
201        for i in 0..device.fabrics.len() {
202            device.register_operational_mdns(i).await?;
203        }
204
205        log::info!(
206            "Device state restored from {} ({} fabric(s))",
207            path,
208            device.fabrics.len()
209        );
210        Ok(device)
211    }
212}