peripheral_core/
lib.rs

1//! `peripheral-core` — external-device (peripheral) connection forensic reader.
2//!
3//! Parses Windows `setupapi.dev.log` device-installation logs into a uniform
4//! [`DeviceConnection`] stream: bus-classified, with each timestamp tagged
5//! authoritative-vs-inferred and the USB iSerial kept distinct from any volume
6//! serial. The input is attacker-controllable evidence — parsing is lenient
7//! (lossy UTF-8), bounds-checked, and never panics. No `unsafe`.
8//!
9//! Findings (DMA-capable device, mass-storage, HID/BadUSB, OS-generated serial)
10//! live in the sibling `peripheral-forensic` crate; this crate only decodes.
11//!
12//! ## v0.2 enrichment (not in this release)
13//!
14//! The richest source — the Windows registry `SYSTEM\CurrentControlSet\Enum\`
15//! keys (USBSTOR/USB), `MountedDevices`, and the device-property `0066`/`0067`
16//! Last-Arrival/Last-Removal `FILETIME`s — plus EVTX device events require the
17//! (unpublished) `winreg-core` and `winevt-forensic` crates. They are deferred
18//! to v0.2; v0.1 is scoped to the self-contained `setupapi.dev.log` source.
19
20#![forbid(unsafe_code)]
21
22pub mod linux_syslog;
23pub mod mounted_volumes;
24pub mod mountpoints2;
25pub mod registry;
26pub mod setupapi;
27pub mod volume_info;
28
29/// The physical/logical bus a peripheral attached through.
30///
31/// The variant drives the DMA-capability and storage-class threat lenses
32/// downstream (see [`DeviceConnection::dma_capable`]).
33#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
34pub enum Bus {
35    /// USB (host-controller mediated; not directly DMA-capable as mass storage).
36    Usb,
37    /// Media Transfer Protocol (phones/cameras) — surfaced via `WpdBusEnumRoot`.
38    Mtp,
39    /// IEEE 1394 FireWire — bus-mastering DMA.
40    FireWire,
41    /// Thunderbolt — PCIe tunnelled, bus-mastering DMA.
42    Thunderbolt,
43    /// PCI Express — bus-mastering DMA.
44    Pcie,
45    /// External SATA — SATA/storage transport, explicitly NOT DMA.
46    Esata,
47    /// SD/MMC card.
48    SdMmc,
49    /// Bluetooth (typically HID/wireless).
50    Bluetooth,
51    /// ExpressCard — PCIe-backed, bus-mastering DMA.
52    ExpressCard,
53    /// SCSI / SAS storage transport.
54    ScsiSas,
55    /// NVMe storage.
56    Nvme,
57    /// Bus could not be determined from the enumerator.
58    Unknown,
59}
60
61impl Bus {
62    /// Classify a bus from a setupapi/instance-id **enumerator** prefix — the
63    /// leading token of a device instance id (`USBSTOR`, `USB`, `1394`, `PCI`,
64    /// `SCSI`, `SD`, `WpdBusEnumRoot`, …), matched case-insensitively.
65    ///
66    /// Returns [`Bus::Unknown`] for an unrecognized or empty enumerator; the
67    /// caller never gets a panic.
68    #[must_use]
69    pub fn from_enumerator(enumerator: &str) -> Self {
70        let e = enumerator.trim().to_ascii_uppercase();
71        match e.as_str() {
72            "USBSTOR" | "USB" => Self::Usb,
73            "1394" => Self::FireWire,
74            "THUNDERBOLT" => Self::Thunderbolt,
75            "PCI" | "PCIE" => Self::Pcie,
76            "SCSI" | "SAS" => Self::ScsiSas,
77            "NVME" => Self::Nvme,
78            "SD" | "MMC" | "SDBUS" => Self::SdMmc,
79            "ESATA" => Self::Esata,
80            "BTHENUM" | "BTHLE" | "BLUETOOTH" => Self::Bluetooth,
81            "EXPRESSCARD" => Self::ExpressCard,
82            "WPDBUSENUMROOT" | "MTP" => Self::Mtp,
83            _ => Self::Unknown,
84        }
85    }
86
87    /// Whether this bus can perform **bus-mastering DMA**, the property that
88    /// makes a device a direct-memory-access attack surface (MITRE T1200).
89    ///
90    /// DMA-capable: FireWire, Thunderbolt, PCIe, ExpressCard. Storage-class
91    /// transports (USB mass storage, eSATA, SD/MMC, SCSI/SAS, NVMe) and
92    /// HID/wireless transports (USB-HID, Bluetooth) are NOT DMA in this model.
93    ///
94    /// Caveat: SD-Express tunnels PCIe and *can* be DMA-capable; this v0.1
95    /// classifier treats bare `SD` as the legacy non-DMA SD/MMC bus, the common
96    /// case. Distinguishing SD-Express needs the device-capability bits that the
97    /// registry/EVTX v0.2 source carries.
98    #[must_use]
99    pub fn is_dma_capable(self) -> bool {
100        matches!(
101            self,
102            Self::FireWire | Self::Thunderbolt | Self::Pcie | Self::ExpressCard
103        )
104    }
105
106    /// Whether this bus is a removable mass-storage transport (the
107    /// data-exfiltration / autorun lens, MITRE T1052.001 / T1091).
108    #[must_use]
109    pub fn is_mass_storage(self) -> bool {
110        matches!(
111            self,
112            Self::Usb | Self::Esata | Self::SdMmc | Self::ScsiSas | Self::Nvme
113        )
114    }
115}
116
117/// How much trust a timestamp carries.
118#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
119pub enum Confidence {
120    /// Directly recorded by the source as the stated event
121    /// (e.g. the setupapi section-header install time → first-seen).
122    Authoritative,
123    /// Derived/undocumented — the value's meaning is inferred, not stated by the
124    /// source (e.g. the registry `0066`/`0067` Last-Arrival/Last-Removal
125    /// device-property `FILETIME`s, which are undocumented).
126    Inferred,
127}
128
129/// A timestamp tagged with its evidentiary confidence.
130///
131/// Pairing the value with its [`Confidence`] in the type makes the
132/// authoritative-vs-inferred distinction impossible to drop on the floor: a
133/// consumer cannot read `value` without also seeing how trustworthy it is.
134#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
135pub struct Stamp {
136    /// Unix epoch seconds.
137    pub value: i64,
138    /// How the value should be trusted.
139    pub confidence: Confidence,
140}
141
142impl Stamp {
143    /// An authoritative (source-stated) timestamp.
144    #[must_use]
145    pub fn authoritative(value: i64) -> Self {
146        Self {
147            value,
148            confidence: Confidence::Authoritative,
149        }
150    }
151
152    /// An inferred (derived/undocumented) timestamp.
153    #[must_use]
154    pub fn inferred(value: i64) -> Self {
155        Self {
156            value,
157            confidence: Confidence::Inferred,
158        }
159    }
160}
161
162/// A MITRE ATT&CK technique a connection is *consistent with* — never a verdict.
163#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
164pub struct MitreRef(pub &'static str);
165
166/// One external-device connection, normalized across sources.
167///
168/// The forensic cautions are baked into the type, not just the docs:
169/// - [`device_serial`](Self::device_serial) is the **USB iSerial** and is a
170///   distinct field from [`volume_serial`](Self::volume_serial) (a filesystem
171///   volume serial), so the two can never be conflated.
172/// - [`serial_is_os_generated`](Self::serial_is_os_generated) records that the
173///   device had no real iSerial (Windows synthesized one), weakening attribution.
174/// - Each timestamp is a [`Stamp`] carrying its authoritative-vs-inferred
175///   [`Confidence`].
176#[derive(Debug, Clone, PartialEq, Eq)]
177pub struct DeviceConnection {
178    // ── Identity ────────────────────────────────────────────────────────────
179    /// The classified bus.
180    pub bus: Bus,
181    /// Device setup-class GUID, when known.
182    pub device_class_guid: Option<String>,
183    /// USB vendor id (`VID_xxxx`).
184    pub vid: Option<u16>,
185    /// USB product id (`PID_xxxx`).
186    pub pid: Option<u16>,
187    /// The **USB iSerial** — the device-unique serial reported by the device.
188    /// DISTINCT from any [`volume_serial`](Self::volume_serial).
189    pub device_serial: Option<String>,
190    /// `true` when the instance-id serial was synthesized by Windows (the
191    /// serial's 2nd character is `&`) — the device exposed no real iSerial, so
192    /// attribution is weaker.
193    pub serial_is_os_generated: bool,
194    /// Human-readable friendly name, when present.
195    pub friendly_name: Option<String>,
196    /// The full device instance id (e.g.
197    /// `USB\VID_0781&PID_5583\1234567890AB`) — the primary key.
198    pub device_instance_id: String,
199
200    // ── Timestamps (each tagged authoritative-vs-inferred) ───────────────────
201    /// First-seen / first-install — authoritative when from the setupapi
202    /// section header.
203    pub first_install: Option<Stamp>,
204    /// Last install/driver event.
205    pub last_install: Option<Stamp>,
206    /// Last arrival (connect). INFERRED — derived from the undocumented registry
207    /// `0066` device property (v0.2).
208    pub last_arrival: Option<Stamp>,
209    /// Last removal (disconnect). INFERRED — derived from the undocumented
210    /// registry `0067` device property (v0.2).
211    pub last_removal: Option<Stamp>,
212
213    // ── Correlation join keys (volume_serial kept DISTINCT from device_serial) ─
214    /// `ParentIdPrefix` — joins the storage device to its volume.
215    pub parent_id_prefix: Option<String>,
216    /// Volume GUID (`\\?\Volume{...}`).
217    pub volume_guid: Option<String>,
218    /// Mounted drive letter.
219    pub drive_letter: Option<char>,
220    /// Filesystem **volume** serial (NTFS/FAT) — DISTINCT from the device's
221    /// USB [`device_serial`](Self::device_serial).
222    pub volume_serial: Option<u32>,
223    /// MBR disk signature.
224    pub disk_signature: Option<u32>,
225
226    // ── Threat lens ──────────────────────────────────────────────────────────
227    /// Whether the bus is bus-mastering DMA-capable (see [`Bus::is_dma_capable`]).
228    pub dma_capable: bool,
229    /// MITRE ATT&CK techniques this connection is *consistent with*.
230    pub mitre: Vec<MitreRef>,
231
232    // ── Provenance ───────────────────────────────────────────────────────────
233    /// Where this record came from (source file + 1-based line).
234    pub source: Provenance,
235}
236
237/// Where a [`DeviceConnection`] was decoded from.
238#[derive(Debug, Clone, PartialEq, Eq)]
239pub struct Provenance {
240    /// The source file (e.g. `setupapi.dev.log`, or the hive name `SYSTEM`).
241    pub file: String,
242    /// 1-based line number of the section header the record came from, for
243    /// line-oriented sources (`setupapi.dev.log`). `0` when the source is not
244    /// line-oriented (e.g. a registry hive — see [`key_path`](Self::key_path)).
245    pub line: usize,
246    /// The full registry key path the record was decoded from, for hive sources
247    /// (e.g. `ControlSet001\Enum\SCSI\Disk&Ven_…\5&22be343f&0&000000`). `None` for
248    /// line-oriented sources.
249    pub key_path: Option<String>,
250}
251
252#[cfg(test)]
253mod tests {
254    use super::*;
255
256    #[test]
257    fn usb_enumerators_classify_as_usb() {
258        assert_eq!(Bus::from_enumerator("USBSTOR"), Bus::Usb);
259        assert_eq!(Bus::from_enumerator("USB"), Bus::Usb);
260        assert_eq!(Bus::from_enumerator("usbstor"), Bus::Usb); // case-insensitive
261    }
262
263    #[test]
264    fn bus_specific_enumerators_classify() {
265        assert_eq!(Bus::from_enumerator("1394"), Bus::FireWire);
266        assert_eq!(Bus::from_enumerator("SCSI"), Bus::ScsiSas);
267        assert_eq!(Bus::from_enumerator("PCI"), Bus::Pcie);
268        assert_eq!(Bus::from_enumerator("SD"), Bus::SdMmc);
269        assert_eq!(Bus::from_enumerator("WpdBusEnumRoot"), Bus::Mtp);
270        assert_eq!(Bus::from_enumerator("THUNDERBOLT"), Bus::Thunderbolt);
271        assert_eq!(Bus::from_enumerator("ESATA"), Bus::Esata);
272        assert_eq!(Bus::from_enumerator("EXPRESSCARD"), Bus::ExpressCard);
273        assert_eq!(Bus::from_enumerator("BTHENUM"), Bus::Bluetooth);
274        assert_eq!(Bus::from_enumerator("NVME"), Bus::Nvme);
275    }
276
277    #[test]
278    fn unknown_enumerator_is_unknown_never_panics() {
279        assert_eq!(Bus::from_enumerator("HID"), Bus::Unknown);
280        assert_eq!(Bus::from_enumerator(""), Bus::Unknown);
281        assert_eq!(Bus::from_enumerator("   "), Bus::Unknown);
282    }
283
284    #[test]
285    fn dma_capable_is_exactly_firewire_thunderbolt_pcie_expresscard() {
286        for b in [Bus::FireWire, Bus::Thunderbolt, Bus::Pcie, Bus::ExpressCard] {
287            assert!(b.is_dma_capable(), "{b:?} must be DMA-capable");
288        }
289        // Storage-only transports are explicitly NOT DMA (eSATA is SATA/storage).
290        for b in [Bus::Usb, Bus::Esata, Bus::SdMmc, Bus::ScsiSas, Bus::Nvme] {
291            assert!(!b.is_dma_capable(), "{b:?} must NOT be DMA-capable");
292        }
293        // HID/wireless transports are not DMA either.
294        for b in [Bus::Bluetooth, Bus::Mtp, Bus::Unknown] {
295            assert!(!b.is_dma_capable(), "{b:?} must NOT be DMA-capable");
296        }
297    }
298
299    #[test]
300    fn mass_storage_classes() {
301        for b in [Bus::Usb, Bus::Esata, Bus::SdMmc, Bus::ScsiSas, Bus::Nvme] {
302            assert!(b.is_mass_storage(), "{b:?} should be mass storage");
303        }
304        for b in [Bus::FireWire, Bus::Thunderbolt, Bus::Bluetooth, Bus::Mtp] {
305            assert!(!b.is_mass_storage(), "{b:?} should not be mass storage");
306        }
307    }
308
309    #[test]
310    fn stamp_carries_confidence() {
311        assert_eq!(
312            Stamp::authoritative(10).confidence,
313            Confidence::Authoritative
314        );
315        assert_eq!(Stamp::inferred(10).confidence, Confidence::Inferred);
316    }
317}
peripheral_core/lib.rs

peripheral_core/
lib.rs
