Port bdinfo and mtdparts, both of which were dead on real captures

CHANGELOG.md

@@ -8,6 +8,26 @@ All notable changes to bootintel-cli are documented here. Format follows [Keep a
 
 ## [Unreleased]
 
+### Added
+- **`bootintel verdict` now reports board info and the flash partition table**
+  when a capture contains a `bdinfo` or `mtdparts` dump. The partition rows carry
+  the `mask_flags` read-only marker, which is the operationally interesting
+  column: it says which partitions an operator at that prompt can rewrite.
+
+  Both were dead code on the engine side and the port started by measuring that,
+  not by assuming it. Across all 31 public corpus logs they produced nothing,
+  while two of those logs contain a full bdinfo dump. The cause was a command
+  gate: the blocks were only parsed once the prompt regex had matched the line
+  where the command was typed, and `Boot-> bdinfo` is not U-Boot's default
+  prompt. They are now recognised by their own shape.
+
+  The discriminator between board info and an environment variable is the
+  whitespace around the `=`: `printenv` emits `baudrate=115200`, `bdinfo` pads to
+  a column and emits `baudrate    = 115200 bps`.
+
+  `verdict --json` gained `bdinfo` and `mtd_device` under `uboot_shell`, and a
+  top-level `mtd_partitions` array, matching the engine's placement.
+
 ## [0.10.0] — 2026-09-28 — the kernel's own hardening report
 
 `bootintel verdict` now answers for captures that never reach a U-Boot prompt.

crates/cli/src/cmd/verdict.rs

@@ -180,6 +180,22 @@ fn json(
         shell.insert("env_used_bytes".into(), used.into());
         shell.insert("env_total_bytes".into(), total.into());
     }
+    // Same placement as the engine: board info and the flash device hang off the
+    // shell, partitions are top level and tagged with the parser that found them.
+    if !session.bdinfo.is_empty() {
+        shell.insert(
+            "bdinfo".into(),
+            session
+                .bdinfo
+                .iter()
+                .map(|(k, v)| (k.clone(), serde_json::Value::from(v.clone())))
+                .collect::<serde_json::Map<String, serde_json::Value>>()
+                .into(),
+        );
+    }
+    if let Some(dev) = &session.mtd_device {
+        shell.insert("mtd_device".into(), dev.clone().into());
+    }
     // Mirrors the engine's `boot_integrity` key names, and omits what was not
     // observed rather than emitting nulls: absence of a field means the capture
     // said nothing, which is different from a field saying "no".
@@ -259,6 +275,13 @@ fn json(
         "uboot_env": session.env.iter()
             .map(|(k, v)| (k.clone(), serde_json::Value::from(v.clone())))
             .collect::<serde_json::Map<String, serde_json::Value>>(),
+        "mtd_partitions": session.mtd_partitions.iter().map(|p| serde_json::json!({
+            "name": p.name,
+            "size": p.size,
+            "offset": p.offset,
+            "read_only": p.read_only,
+            "source": "uboot_mtdparts",
+        })).collect::<Vec<_>>(),
         "boot_chain_verdict": verdicts.iter().map(|v| serde_json::json!({
             "title": v.title,
             "state": v.state,
@@ -320,6 +343,35 @@ pub(crate) fn write_text<W: Write>(
         session.env.len(),
         if session.env.len() == 1 { "" } else { "s" }
     )?;
+    if !session.bdinfo.is_empty() {
+        writeln!(
+            out,
+            "    board info   {} field{}",
+            session.bdinfo.len(),
+            if session.bdinfo.len() == 1 { "" } else { "s" }
+        )?;
+    }
+    if !session.mtd_partitions.is_empty() {
+        let dev = session.mtd_device.as_deref().unwrap_or("flash");
+        writeln!(
+            out,
+            "    {} partitions on {}",
+            session.mtd_partitions.len(),
+            sanitize_for_term(dev)
+        )?;
+        for p in &session.mtd_partitions {
+            // The read-only flag is the operationally interesting column: it is
+            // what says which partitions an operator at this prompt can rewrite.
+            writeln!(
+                out,
+                "      {:<16} 0x{:08x} @ 0x{:08x}{}",
+                sanitize_for_term(&p.name),
+                p.size,
+                p.offset,
+                if p.read_only { "  read-only" } else { "" }
+            )?;
+        }
+    }
     if let Some(check) = &integrity.image_check {
         let mechanism = if check == "fit_hash" {
             let algos = if integrity.image_hash_algorithms.is_empty() {

crates/detectors/src/boot_chain.rs

@@ -46,6 +46,12 @@ pub struct UbootSession {
     pub env: BTreeMap<String, String>,
     pub env_used_bytes: Option<u64>,
     pub env_total_bytes: Option<u64>,
+    /// `bdinfo` output: what the board reports about itself.
+    pub bdinfo: BTreeMap<String, String>,
+    /// The flash device named by an `mtdparts` dump.
+    pub mtd_device: Option<String>,
+    /// Partitions from an `mtdparts` dump, in the order printed.
+    pub mtd_partitions: Vec<MtdPartition>,
 }
 
 use std::sync::LazyLock;
@@ -239,6 +245,72 @@ pub fn parse_integrity(log: &str) -> BootIntegrity {
     bi
 }
 
+// bdinfo prints aligned `name = value`. WHITESPACE BOTH SIDES OF THE `=` IS
+// REQUIRED, and it is what separates a bdinfo line from an environment line:
+// `printenv` emits `ethaddr=00:1F:...` with no spaces, bdinfo pads to a column
+// and emits `ethaddr     = 00:1F:...`. Without that, every environment dump
+// containing baudrate or ethaddr would also be read as board info.
+static RE_BDINFO: LazyLock<Regex> =
+    LazyLock::new(|| Regex::new(r"^\s*([A-Za-z][\w /()\-]{0,31}?)\s+=\s+(\S.*?)\s*$").unwrap());
+
+/// The allowlist is what makes bdinfo self-evidencing, which matters because the
+/// command that produced it cannot be relied on: bootintel-20 prints a full dump
+/// after `Boot-> bdinfo`, and `Boot->` is not U-Boot's default prompt, so a
+/// command-gated parser read that dump as nothing at all.
+///
+/// `start` and `size` are deliberately absent: too generic to stand alone.
+/// bootintel-5 prints an MTD table as `mtd_part[0]:` / `name = KERNEL` /
+/// `size = 0x180000`, and `size` in this list recorded that as board info.
+const BDINFO_KEYS: &[&str] = &[
+    "arch_number",
+    "boot_params",
+    "dram bank",
+    "flashstart",
+    "flashsize",
+    "flashoffset",
+    "baudrate",
+    "relocaddr",
+    "reloc off",
+    "ethaddr",
+    "ip_addr",
+    "fdt_blob",
+    "irq_sp",
+    "sp start",
+    "eth0name",
+    "memstart",
+    "memsize",
+    "eth1name",
+    "ethaddr1",
+    "current eth",
+    "fdt_addr",
+    "sp_start",
+    "reloc_off",
+    "dram_bank",
+];
+
+// `device nor0 <spi0.0>, # parts = 4`. The bracketed chip identifier is optional
+// and the space in `# parts` is real. The engine's first version of this pattern
+// required `#parts` with no space and no brackets, so it never matched U-Boot's
+// actual output: the partition lines parsed and the device name did not. No
+// public corpus log contains an mtdparts dump, so nothing caught it until a
+// fixture was written for the documented format.
+static RE_MTD_DEV: LazyLock<Regex> = LazyLock::new(|| {
+    Regex::new(r"(?i)^\s*device\s+(\S+)(?:\s+<[^>]*>)?\s*,\s*#\s*parts\s*=\s*(\d+)").unwrap()
+});
+static RE_MTD_PART: LazyLock<Regex> = LazyLock::new(|| {
+    Regex::new(r"(?i)^\s*\d+:\s*(\S+)\s+0x([0-9a-f]+)\s+0x([0-9a-f]+)\s+(\d)").unwrap()
+});
+
+/// One partition as `mtdparts` printed it at the prompt.
+#[derive(Debug, Default, Clone, PartialEq, Eq)]
+pub struct MtdPartition {
+    pub name: String,
+    pub size: u64,
+    pub offset: u64,
+    /// The `mask_flags` column: 1 means the partition is marked read-only.
+    pub read_only: bool,
+}
+
 /// Truncate to `max` CHARACTERS, mirroring Python's `s[:max]`.
 ///
 /// `String::truncate` counts bytes and panics mid-codepoint, and a capture is
@@ -326,6 +398,49 @@ pub fn parse_session(log: &str) -> UbootSession {
             continue;
         }
 
+        // bdinfo and mtdparts, recognised by their own shape rather than by
+        // having seen the command that produced them, for the reason in
+        // BDINFO_KEYS. Checked before the continuation logic so a bdinfo line
+        // is never appended to a buffered environment value.
+        if let Some(caps) = RE_BDINFO.captures(line) {
+            let key = caps[1].trim();
+            if BDINFO_KEYS.contains(&key.to_ascii_lowercase().as_str()) {
+                s.bdinfo
+                    .entry(key.to_string())
+                    .or_insert_with(|| caps[2].trim().to_string());
+                note(&mut s, line);
+                continue;
+            }
+        }
+        if let Some(caps) = RE_MTD_DEV.captures(line) {
+            if s.mtd_device.is_none() {
+                s.mtd_device = Some(caps[1].to_string());
+            }
+            note(&mut s, line);
+            continue;
+        }
+        if let Some(caps) = RE_MTD_PART.captures(line) {
+            // Hex without a `0x`, as U-Boot prints it. A width beyond u64 is not
+            // a partition table, so a failed parse drops the row rather than
+            // inventing a zero.
+            if let (Ok(size), Ok(offset)) = (
+                u64::from_str_radix(&caps[2], 16),
+                u64::from_str_radix(&caps[3], 16),
+            ) {
+                let part = MtdPartition {
+                    name: caps[1].to_string(),
+                    size,
+                    offset,
+                    read_only: &caps[4] == "1",
+                };
+                if !s.mtd_partitions.contains(&part) {
+                    s.mtd_partitions.push(part);
+                }
+                note(&mut s, line);
+                continue;
+            }
+        }
+
         // A long U-Boot value wraps in a terminal capture, so the continuation
         // has no `KEY=`. Treating it as a boundary discarded whole
         // environments. Append instead, bounded: a couple of wrapped lines is

crates/detectors/tests/boot_chain.rs

@@ -149,6 +149,23 @@ fn render(name: &str, log: &str) -> Vec<String> {
         "ignored_kernel_parameters",
         h.ignored_kernel_parameters.as_deref(),
     );
+    for (key, value) in &session.bdinfo {
+        field(&mut out, "  ", "bdinfo", &format!("{key}={value}"));
+    }
+    if let Some(dev) = &session.mtd_device {
+        field(&mut out, "  ", "mtd_device", dev);
+    }
+    for part in &session.mtd_partitions {
+        field(
+            &mut out,
+            "  ",
+            "mtd_part",
+            &format!(
+                "{} size=0x{:x} offset=0x{:x} ro={}",
+                part.name, part.size, part.offset, part.read_only
+            ),
+        );
+    }
     for (key, value) in &session.env {
         field(&mut out, "  ", "env", &format!("{key}={value}"));
     }
@@ -461,3 +478,82 @@ fn a_check_with_no_captured_result_is_unknown_rather_than_passing() {
         .expect("a verdict");
     assert_eq!(v.state, "unknown");
 }
+
+/// bdinfo is recognised by its own shape, because the command that produced it
+/// cannot be relied on: bootintel-20 prints a full dump after `Boot-> bdinfo`,
+/// and `Boot->` is not U-Boot's default prompt. A command-gated parser read that
+/// entire dump as nothing.
+#[test]
+fn a_bdinfo_dump_behind_a_vendor_prompt_is_still_read() {
+    let log = "Boot-> bdinfo\n\
+               boot_params = 0x87D2EFB0\n\
+               memstart    = 0x80000000\n\
+               flashsize   = 0x01000000\n\
+               ethaddr     = 00:1F:45:F2:B7:3B\n";
+    let s = boot_chain::parse_session(log);
+    assert_eq!(
+        s.bdinfo.get("boot_params").map(String::as_str),
+        Some("0x87D2EFB0")
+    );
+    assert_eq!(
+        s.bdinfo.get("memstart").map(String::as_str),
+        Some("0x80000000")
+    );
+    assert_eq!(s.bdinfo.len(), 4);
+    assert!(s.reached, "a bdinfo dump proves someone was at the prompt");
+}
+
+/// The discriminator between board info and an environment variable is the
+/// whitespace around the `=`. Without it, every environment dump containing
+/// baudrate or ethaddr would also be recorded as board info.
+#[test]
+fn an_environment_line_is_not_board_info() {
+    let log = "=> printenv\nbaudrate=115200\nethaddr=00:11:22:33:44:55\n\
+               Environment size: 40/65532 bytes\n";
+    let s = boot_chain::parse_session(log);
+    assert!(
+        s.bdinfo.is_empty(),
+        "read the environment as board info: {:?}",
+        s.bdinfo
+    );
+    assert_eq!(s.env.len(), 2);
+}
+
+/// `size` and `start` are too generic to be board-info keys on their own.
+/// bootintel-5 prints an MTD table in a vendor format whose rows are exactly
+/// `size = 0x180000`, and treating that as bdinfo was a live false positive.
+#[test]
+fn a_vendor_mtd_table_is_not_board_info() {
+    let log = "mtd_part[0]:\nname = KERNEL\nsize = 0x180000\noffset = 0x37000\n";
+    let s = boot_chain::parse_session(log);
+    assert!(s.bdinfo.is_empty(), "{:?}", s.bdinfo);
+}
+
+/// U-Boot prints `device nor0 <spi0.0>, # parts = 4`: the bracketed chip id is
+/// optional and the space in `# parts` is real. The engine's first pattern
+/// required neither and so never matched, recording the partitions but not the
+/// device they belong to.
+#[test]
+fn an_mtdparts_dump_is_parsed_including_its_device() {
+    let log = "=> mtdparts\n\n\
+               device nor0 <spi0.0>, # parts = 4\n \
+               #: name                size            offset          mask_flags\n \
+               0: u-boot              0x00020000      0x00000000      1\n \
+               1: kernel              0x00100000      0x00020000      0\n";
+    let s = boot_chain::parse_session(log);
+    assert_eq!(s.mtd_device.as_deref(), Some("nor0"));
+    assert_eq!(s.mtd_partitions.len(), 2);
+    assert_eq!(s.mtd_partitions[0].name, "u-boot");
+    assert_eq!(s.mtd_partitions[0].size, 0x20000);
+    assert!(
+        s.mtd_partitions[0].read_only,
+        "mask_flags 1 means read-only"
+    );
+    assert!(!s.mtd_partitions[1].read_only);
+}
+
+#[test]
+fn a_device_line_without_the_bracketed_chip_id_also_parses() {
+    let s = boot_chain::parse_session("device nand0, #parts = 2\n");
+    assert_eq!(s.mtd_device.as_deref(), Some("nand0"));
+}