houndd: fetch definitions from defs.houndav.com, and refuse anything unsigned
Closes Phase 3's delivery half. `hound update` now asks the definitions
host what exists, downloads what this machine lacks, verifies it, and
installs it. Verified end to end against the live host over TLS:
starting from an empty directory:
defs: no verified packs were found
hound update:
definitions: 1 pack(s) installed, 0 already current
crates-io-2026.08.21.pack — 19 indicators, version 2026.08.21
loaded 19 indicators from 1 pack(s) [2026.08.21]
and immediately afterwards a lockfile naming rustdecimal is flagged,
while tokio beside it is not.
running it again:
definitions: definitions are up to date (1 pack(s))
a pack with one byte flipped in its signed payload, advertised in the
index with a correct hash and a version of 9999.1.1:
definitions: 0 pack(s) installed, 1 up to date, 1 REJECTED
tampered-test.pack: the definitions pack is not signed by Hound and
was discarded
Three refusals are the design:
* THE INDEX IS A HINT, NEVER AN AUTHORITY. It says which packs exist and
what they hash to, and both are unverified — anyone who can serve the
index can lie about either. Only the Ed25519 signature decides whether
a pack is real. A tampered index can waste bandwidth and nothing else,
which is exactly what the test above demonstrates: correct hash,
higher version, still refused.
* NOTHING UNVERIFIED REACHES THE DEFINITIONS DIRECTORY. Downloaded to a
temp file, verified there, then moved with a rename inside the same
directory so it is atomic. The daemon cannot observe a half-written
pack, and a crash mid-download leaves a stray temp file rather than a
loadable one.
* A FILENAME FROM A REMOTE INDEX IS UNTRUSTED INPUT. The updater runs as
root, so an entry of ../../../etc/cron.d/evil.pack would be remote code
execution. Only a plain basename ending in .pack, with no separators,
no dot-dot and no leading dot, is accepted. Tested against eight
hostile shapes.
Sizes and timeouts are bounded — a pack is a list of package names, so a
server offering a hundred gigabytes is broken or hostile and the
difference does not matter to a full disk. The read is bounded
independently of Content-Length, which is also just something the server
said.
Definitions are fetched BEFORE rules are reloaded, and a failure to fetch
does not stop the reload. No network, a mirror down, a pack that will not
verify — none of those are a reason to skip the half that still works.
HOUNDD_DEFS_URL points the client at a mirror, which matters for the
air-gapped deployments that are a real part of the Fleet story.
build-pack now writes index.json beside the pack, so publishing is one
command.
358 tests pass.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
This commit is contained in:
Hound
parent
2d06632fa9
commit
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7 changed files with 802 additions and 0 deletions
344
Cargo.lock
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generated
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@ -893,6 +893,15 @@ version = "0.2.0"
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]
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"cc",
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]
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[[package]]
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"zerovec",
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]
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[[package]]
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[[package]]
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name = "icu_provider"
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"icu_locale_core",
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"writeable",
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"yoke",
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"zerofrom",
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"zerotrie",
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"zerovec",
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]
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name = "id-arena"
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version = "2.3.0"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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checksum = "b9e0384b61958566e926dc50660321d12159025e767c18e043daf26b70104c39"
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[[package]]
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name = "ignore"
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version = "0.4.33"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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]
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name = "percent-encoding"
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name = "pin-project-lite"
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"libc",
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]
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"subtle",
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"zeroize",
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]
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"zeroize",
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source = "registry+https://github.com/rust-lang/crates.io-index"
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checksum = "b4ac048d71ede7ee76d585517add45da530660ef4390e49b098733c6e897f254"
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"once_cell",
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"rustls",
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]
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version = "0.26.11"
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dependencies = [
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checksum = "7dcd9d09a39985f5344844e66b0c530a33843579125f23e21e9f0f220850f22a"
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dependencies = [
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"rustls-pki-types",
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]
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name = "windows-sys"
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version = "0.52.0"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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checksum = "282be5f36a8ce781fad8c8ae18fa3f9beff57ec1b52cb3de0789201425d9a33d"
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dependencies = [
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"windows-targets",
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]
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version = "0.59.0"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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name = "writeable"
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|
||||
checksum = "de844c262c8848816172cef550288e7dc6c7b7814b4ee56b3e1553f275f1858e"
|
||||
dependencies = [
|
||||
"proc-macro2",
|
||||
"quote",
|
||||
"syn 2.0.119",
|
||||
"synstructure",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "zerocopy"
|
||||
version = "0.8.56"
|
||||
|
|
@ -3012,12 +3302,66 @@ dependencies = [
|
|||
"syn 2.0.119",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "zerofrom"
|
||||
version = "0.1.8"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "0ec05a11813ea801ff6d75110ad09cd0824ddba17dfe17128ea0d5f68e6c5272"
|
||||
dependencies = [
|
||||
"zerofrom-derive",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "zerofrom-derive"
|
||||
version = "0.1.7"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "11532158c46691caf0f2593ea8358fed6bbf68a0315e80aae9bd41fbade684a1"
|
||||
dependencies = [
|
||||
"proc-macro2",
|
||||
"quote",
|
||||
"syn 2.0.119",
|
||||
"synstructure",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "zeroize"
|
||||
version = "1.9.0"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "e13c156562582aa81c60cb29407084cdb54c4164760106ab78e6c5b0858cf64e"
|
||||
|
||||
[[package]]
|
||||
name = "zerotrie"
|
||||
version = "0.2.5"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "4ea269c3bd32f0a32c321907a2ae912ba6f4649bb0fc764a15627e99a7095a3f"
|
||||
dependencies = [
|
||||
"displaydoc",
|
||||
"yoke",
|
||||
"zerofrom",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "zerovec"
|
||||
version = "0.11.8"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "bb0464e17806c1d976d5cba29399c7f08e516e279e2ba493f63123b5fca67dd8"
|
||||
dependencies = [
|
||||
"yoke",
|
||||
"zerofrom",
|
||||
"zerovec-derive",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "zerovec-derive"
|
||||
version = "0.11.6"
|
||||
source = "registry+https://github.com/rust-lang/crates.io-index"
|
||||
checksum = "34df6fc39dbd26ddc9c10e6a2984476e13acce22e64e4487636ef494369225da"
|
||||
dependencies = [
|
||||
"proc-macro2",
|
||||
"quote",
|
||||
"syn 3.0.3",
|
||||
]
|
||||
|
||||
[[package]]
|
||||
name = "zip"
|
||||
version = "8.6.0"
|
||||
|
|
|
|||
|
|
@ -21,6 +21,7 @@ yara-x = "1.19"
|
|||
libc = "0.2"
|
||||
sha2 = "0.10"
|
||||
ed25519-dalek = { version = "2", features = ["rand_core"] }
|
||||
ureq = { version = "2", default-features = false, features = ["tls", "gzip"] }
|
||||
hound-defs = { path = "crates/hound-defs" }
|
||||
hound-mcp = { path = "crates/hound-mcp" }
|
||||
|
||||
|
|
|
|||
|
|
@ -98,6 +98,43 @@ fn main() {
|
|||
let signed = pack::sign(&p, &key, &key_id).expect("signing the pack");
|
||||
std::fs::write(out, serde_json::to_string(&signed).expect("encoding")).expect("writing");
|
||||
|
||||
// Write/refresh index.json beside the pack, so the update client has
|
||||
// something to read. The index is advisory — the pack's signature is
|
||||
// what decides whether it is genuine — but a correct hash here saves
|
||||
// every agent a download it does not need.
|
||||
let out_path = std::path::Path::new(out);
|
||||
if let Some(dir) = out_path.parent() {
|
||||
let mut entries: Vec<serde_json::Value> = Vec::new();
|
||||
for e in std::fs::read_dir(dir).into_iter().flatten().flatten() {
|
||||
let p = e.path();
|
||||
if p.extension().is_none_or(|x| x != "pack") {
|
||||
continue;
|
||||
}
|
||||
let Ok(bytes) = std::fs::read(&p) else { continue };
|
||||
let mut h = <sha2::Sha256 as sha2::Digest>::new();
|
||||
sha2::Digest::update(&mut h, &bytes);
|
||||
let digest = format!("{:x}", sha2::Digest::finalize(h));
|
||||
let name = p.file_name().unwrap().to_string_lossy().into_owned();
|
||||
let ver = serde_json::from_slice::<serde_json::Value>(&bytes)
|
||||
.ok()
|
||||
.and_then(|v| {
|
||||
let payload = v.get("payload")?.as_str()?.to_string();
|
||||
Some(payload)
|
||||
})
|
||||
.map(|_| version.clone())
|
||||
.unwrap_or_default();
|
||||
entries.push(serde_json::json!({
|
||||
"file": name, "version": ver, "sha256": digest, "size": bytes.len()
|
||||
}));
|
||||
}
|
||||
entries.sort_by(|a, b| a["file"].as_str().cmp(&b["file"].as_str()));
|
||||
let index = serde_json::json!({ "packs": entries });
|
||||
let index_path = dir.join("index.json");
|
||||
std::fs::write(&index_path, serde_json::to_string_pretty(&index).unwrap())
|
||||
.expect("writing index.json");
|
||||
println!("index {} ({} pack(s))", index_path.display(), index["packs"].as_array().unwrap().len());
|
||||
}
|
||||
|
||||
println!("read {files} OSV records");
|
||||
println!("packed {} indicators", p.indicators.len());
|
||||
println!("version {version}");
|
||||
|
|
|
|||
|
|
@ -23,3 +23,4 @@ libc.workspace = true
|
|||
sha2.workspace = true
|
||||
hound-defs.workspace = true
|
||||
ed25519-dalek.workspace = true
|
||||
ureq.workspace = true
|
||||
|
|
|
|||
|
|
@ -53,6 +53,7 @@ mod realtime;
|
|||
mod rootkit;
|
||||
mod rules;
|
||||
mod settings;
|
||||
mod update;
|
||||
#[cfg(test)]
|
||||
mod test_util;
|
||||
|
||||
|
|
@ -705,7 +706,43 @@ fn gate_status(st: &DaemonState) -> hound_api::GateStatus {
|
|||
fn update(st: &DaemonState) -> Result<hound_api::UpdateResult> {
|
||||
use hound_api::UpdateResult;
|
||||
|
||||
// Definitions first, rules second. Fetching can fail — no network, a
|
||||
// mirror down, a pack that will not verify — and none of that is a
|
||||
// reason to skip reloading what is already on disk. An update that
|
||||
// refuses to do the half it can do is worse than one that reports
|
||||
// both halves honestly.
|
||||
let mut lines: Vec<String> = Vec::new();
|
||||
let keys = defs::trusted_keys();
|
||||
let trusted: Vec<(&str, ed25519_dalek::VerifyingKey)> =
|
||||
keys.iter().map(|(id, k)| (id.as_str(), *k)).collect();
|
||||
|
||||
match update::run(&update::install_dir(), &trusted) {
|
||||
Ok(outcome) => {
|
||||
lines.push(format!("definitions: {}", outcome.summary()));
|
||||
lines.extend(outcome.log.iter().map(|l| format!(" {l}")));
|
||||
if !outcome.installed.is_empty() {
|
||||
let loaded = st.defs.reload();
|
||||
lines.push(format!(
|
||||
" loaded {} indicators from {} pack(s) [{}]",
|
||||
loaded.indicators,
|
||||
loaded.packs.len(),
|
||||
loaded.version
|
||||
));
|
||||
}
|
||||
let sev = if outcome.rejected.is_empty() { "info" } else { "warn" };
|
||||
st.events
|
||||
.push("update", sev, format!("definitions: {}", outcome.summary()));
|
||||
}
|
||||
Err(e) => {
|
||||
// Reported, not fatal.
|
||||
lines.push(format!("definitions: could not update — {e}"));
|
||||
st.events
|
||||
.push("update", "warn", format!("definitions update failed: {e}"));
|
||||
}
|
||||
}
|
||||
|
||||
let (ok, command, combined) = engine::engine().update()?;
|
||||
let combined = format!("{}\n{combined}", lines.join("\n"));
|
||||
st.events.push(
|
||||
"update",
|
||||
if ok { "info" } else { "warn" },
|
||||
|
|
|
|||
382
crates/houndd/src/update.rs
Normal file
382
crates/houndd/src/update.rs
Normal file
|
|
@ -0,0 +1,382 @@
|
|||
//! Fetching definition packs.
|
||||
//!
|
||||
//! The agent asks `defs.houndav.com` what exists, downloads what it does
|
||||
//! not have, and installs it. The interesting part is what it refuses to
|
||||
//! trust along the way.
|
||||
//!
|
||||
//! **The index is a hint, never an authority.** It says which packs exist
|
||||
//! and what they should hash to, and both claims are unverified — anyone
|
||||
//! who can serve the index can lie about either. The only thing that
|
||||
//! decides whether a pack is real is its Ed25519 signature, checked
|
||||
//! against the public key compiled into this binary. A tampered index can
|
||||
//! therefore waste bandwidth and nothing else.
|
||||
//!
|
||||
//! **Nothing unverified ever lands in the definitions directory.** A pack
|
||||
//! is downloaded to a temporary file, verified there, and only then moved
|
||||
//! into place with a rename. A rename within one directory is atomic, so
|
||||
//! the daemon can never observe a half-written pack — and a crash
|
||||
//! mid-download leaves a stray temp file rather than a loadable one.
|
||||
//!
|
||||
//! **Everything is bounded.** A definitions pack is small; a server that
|
||||
//! offers a hundred gigabytes is either broken or hostile, and the
|
||||
//! difference does not matter to a disk that is now full.
|
||||
|
||||
use anyhow::{bail, Context, Result};
|
||||
use hound_defs::{pack, SignedPack};
|
||||
use serde::Deserialize;
|
||||
use sha2::{Digest, Sha256};
|
||||
use std::io::Read;
|
||||
use std::path::{Path, PathBuf};
|
||||
|
||||
/// Where packs come from. Overridable for testing and for air-gapped
|
||||
/// mirrors, which are a real deployment rather than a hypothetical.
|
||||
pub fn base_url() -> String {
|
||||
std::env::var("HOUNDD_DEFS_URL").unwrap_or_else(|_| "https://defs.houndav.com".into())
|
||||
}
|
||||
|
||||
/// A pack is a list of package names. Anything approaching this is not
|
||||
/// one.
|
||||
const MAX_PACK_BYTES: u64 = 64 * 1024 * 1024;
|
||||
|
||||
/// The index is a handful of entries.
|
||||
const MAX_INDEX_BYTES: u64 = 1024 * 1024;
|
||||
|
||||
/// Long enough for a slow link, short enough that `hound update` cannot
|
||||
/// hang a terminal indefinitely.
|
||||
const TIMEOUT_SECS: u64 = 30;
|
||||
|
||||
#[derive(Debug, Clone, Deserialize)]
|
||||
pub struct IndexEntry {
|
||||
pub file: String,
|
||||
#[serde(default)]
|
||||
pub version: String,
|
||||
/// Advisory only — see the module note. Used to skip a download we
|
||||
/// already have, never to decide a pack is genuine.
|
||||
#[serde(default)]
|
||||
pub sha256: String,
|
||||
}
|
||||
|
||||
#[derive(Debug, Clone, Deserialize, Default)]
|
||||
pub struct Index {
|
||||
#[serde(default)]
|
||||
pub packs: Vec<IndexEntry>,
|
||||
}
|
||||
|
||||
/// What one update run did.
|
||||
#[derive(Debug, Default)]
|
||||
pub struct Outcome {
|
||||
pub installed: Vec<String>,
|
||||
pub already_current: Vec<String>,
|
||||
pub rejected: Vec<String>,
|
||||
pub log: Vec<String>,
|
||||
}
|
||||
|
||||
impl Outcome {
|
||||
pub fn summary(&self) -> String {
|
||||
if !self.rejected.is_empty() {
|
||||
return format!(
|
||||
"{} pack(s) installed, {} up to date, {} REJECTED",
|
||||
self.installed.len(),
|
||||
self.already_current.len(),
|
||||
self.rejected.len()
|
||||
);
|
||||
}
|
||||
if self.installed.is_empty() {
|
||||
return format!("definitions are up to date ({} pack(s))", self.already_current.len());
|
||||
}
|
||||
format!(
|
||||
"{} pack(s) installed, {} already current",
|
||||
self.installed.len(),
|
||||
self.already_current.len()
|
||||
)
|
||||
}
|
||||
}
|
||||
|
||||
/// A filename from a remote index is untrusted input.
|
||||
///
|
||||
/// Without this, an entry of `../../../etc/cron.d/evil` would have the
|
||||
/// updater write wherever it liked — a path traversal handed to a process
|
||||
/// running as root. Only a plain basename ending in `.pack` is accepted.
|
||||
pub fn safe_pack_name(name: &str) -> bool {
|
||||
!name.is_empty()
|
||||
&& name.len() <= 128
|
||||
&& name.ends_with(".pack")
|
||||
&& !name.contains('/')
|
||||
&& !name.contains('\\')
|
||||
&& !name.contains("..")
|
||||
&& !name.starts_with('.')
|
||||
&& name
|
||||
.chars()
|
||||
.all(|c| c.is_ascii_alphanumeric() || matches!(c, '-' | '_' | '.'))
|
||||
}
|
||||
|
||||
fn sha256_hex(bytes: &[u8]) -> String {
|
||||
let mut h = Sha256::new();
|
||||
h.update(bytes);
|
||||
format!("{:x}", h.finalize())
|
||||
}
|
||||
|
||||
fn get(url: &str, max: u64) -> Result<Vec<u8>> {
|
||||
let resp = ureq::AgentBuilder::new()
|
||||
.timeout(std::time::Duration::from_secs(TIMEOUT_SECS))
|
||||
.user_agent(concat!("hound/", env!("CARGO_PKG_VERSION")))
|
||||
.build()
|
||||
.get(url)
|
||||
.call()
|
||||
.with_context(|| format!("fetching {url}"))?;
|
||||
|
||||
let mut buf = Vec::new();
|
||||
// take() bounds the read regardless of what Content-Length claims,
|
||||
// because Content-Length is also just something the server said.
|
||||
resp.into_reader()
|
||||
.take(max + 1)
|
||||
.read_to_end(&mut buf)
|
||||
.with_context(|| format!("reading {url}"))?;
|
||||
if buf.len() as u64 > max {
|
||||
bail!("{url} is larger than {max} bytes; refusing it");
|
||||
}
|
||||
Ok(buf)
|
||||
}
|
||||
|
||||
/// Fetch the index.
|
||||
pub fn fetch_index(base: &str) -> Result<Index> {
|
||||
let bytes = get(&format!("{base}/index.json"), MAX_INDEX_BYTES)?;
|
||||
serde_json::from_slice(&bytes).context("the definitions index is not valid JSON")
|
||||
}
|
||||
|
||||
/// Fetch, verify and install everything the index offers that we lack.
|
||||
pub fn run(dir: &Path, trusted: &[(&str, ed25519_dalek::VerifyingKey)]) -> Result<Outcome> {
|
||||
let base = base_url();
|
||||
let mut out = Outcome::default();
|
||||
|
||||
if trusted.is_empty() {
|
||||
bail!("no signing key is trusted by this build, so no pack could be verified");
|
||||
}
|
||||
std::fs::create_dir_all(dir)
|
||||
.with_context(|| format!("creating {}", dir.display()))?;
|
||||
|
||||
let index = fetch_index(&base)?;
|
||||
if index.packs.is_empty() {
|
||||
out.log.push(format!("{base} offers no packs"));
|
||||
return Ok(out);
|
||||
}
|
||||
|
||||
for entry in &index.packs {
|
||||
if !safe_pack_name(&entry.file) {
|
||||
out.rejected.push(entry.file.clone());
|
||||
out.log
|
||||
.push(format!("refused a pack name that is not a plain filename: {:?}", entry.file));
|
||||
continue;
|
||||
}
|
||||
let dest = dir.join(&entry.file);
|
||||
|
||||
// Already have these exact bytes? Nothing to do.
|
||||
if let Ok(existing) = std::fs::read(&dest) {
|
||||
if !entry.sha256.is_empty() && sha256_hex(&existing) == entry.sha256 {
|
||||
out.already_current.push(entry.file.clone());
|
||||
continue;
|
||||
}
|
||||
}
|
||||
|
||||
let url = format!("{base}/{}", entry.file);
|
||||
let bytes = match get(&url, MAX_PACK_BYTES) {
|
||||
Ok(b) => b,
|
||||
Err(e) => {
|
||||
out.rejected.push(entry.file.clone());
|
||||
out.log.push(format!("{}: {e}", entry.file));
|
||||
continue;
|
||||
}
|
||||
};
|
||||
|
||||
// VERIFY BEFORE INSTALL. Not after, and not "install then check".
|
||||
let signed: SignedPack = match serde_json::from_slice(&bytes) {
|
||||
Ok(s) => s,
|
||||
Err(e) => {
|
||||
out.rejected.push(entry.file.clone());
|
||||
out.log.push(format!("{}: not a definitions pack ({e})", entry.file));
|
||||
continue;
|
||||
}
|
||||
};
|
||||
let verified = match pack::verify(&signed, trusted) {
|
||||
Ok(p) => p,
|
||||
Err(e) => {
|
||||
out.rejected.push(entry.file.clone());
|
||||
out.log.push(format!("{}: {e}", entry.file));
|
||||
continue;
|
||||
}
|
||||
};
|
||||
|
||||
// Write beside the destination so the rename stays within one
|
||||
// filesystem and is therefore atomic.
|
||||
let tmp = dir.join(format!(".{}.part", entry.file));
|
||||
if let Err(e) = std::fs::write(&tmp, &bytes) {
|
||||
out.rejected.push(entry.file.clone());
|
||||
out.log.push(format!("{}: could not write: {e}", entry.file));
|
||||
continue;
|
||||
}
|
||||
if let Err(e) = std::fs::rename(&tmp, &dest) {
|
||||
let _ = std::fs::remove_file(&tmp);
|
||||
out.rejected.push(entry.file.clone());
|
||||
out.log.push(format!("{}: could not install: {e}", entry.file));
|
||||
continue;
|
||||
}
|
||||
|
||||
out.log.push(format!(
|
||||
"{} — {} indicators, version {}",
|
||||
entry.file,
|
||||
verified.indicators.len(),
|
||||
verified.version
|
||||
));
|
||||
out.installed.push(entry.file.clone());
|
||||
}
|
||||
|
||||
Ok(out)
|
||||
}
|
||||
|
||||
/// Where the daemon keeps packs, creating the system location when root.
|
||||
pub fn install_dir() -> PathBuf {
|
||||
if let Some(dir) = std::env::var_os("HOUNDD_DEFS_DIR") {
|
||||
return PathBuf::from(dir);
|
||||
}
|
||||
if crate::caps::is_root() {
|
||||
return PathBuf::from("/var/lib/hound/defs");
|
||||
}
|
||||
let home = std::env::var("HOME").unwrap_or_else(|_| "/root".into());
|
||||
PathBuf::from(home).join(".local/share/hound/defs")
|
||||
}
|
||||
|
||||
#[cfg(test)]
|
||||
mod tests {
|
||||
use super::*;
|
||||
|
||||
// ── the untrusted filename ──
|
||||
|
||||
#[test]
|
||||
fn a_traversing_pack_name_is_refused() {
|
||||
// The updater runs as root. A remote index that could name
|
||||
// ../../../etc/cron.d/evil would be remote code execution.
|
||||
for bad in [
|
||||
"../../../etc/cron.d/evil.pack",
|
||||
"..%2f..%2fevil.pack",
|
||||
"/etc/evil.pack",
|
||||
"sub/dir.pack",
|
||||
"a\\b.pack",
|
||||
".hidden.pack",
|
||||
"no-extension",
|
||||
"",
|
||||
] {
|
||||
assert!(!safe_pack_name(bad), "{bad:?} should have been refused");
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn an_ordinary_pack_name_is_accepted() {
|
||||
for good in ["crates-io-2026.08.21.pack", "npm_2026.pack", "a.pack"] {
|
||||
assert!(safe_pack_name(good), "{good:?} should have been accepted");
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn an_absurdly_long_name_is_refused() {
|
||||
assert!(!safe_pack_name(&format!("{}.pack", "a".repeat(200))));
|
||||
}
|
||||
|
||||
// ── outcome reporting ──
|
||||
|
||||
#[test]
|
||||
fn a_rejection_is_never_hidden_behind_a_success_count() {
|
||||
let mut o = Outcome::default();
|
||||
o.installed.push("a.pack".into());
|
||||
o.rejected.push("b.pack".into());
|
||||
let s = o.summary();
|
||||
assert!(s.contains("REJECTED"), "a refused pack must be visible: {s}");
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn nothing_to_do_reads_as_up_to_date() {
|
||||
let mut o = Outcome::default();
|
||||
o.already_current.push("a.pack".into());
|
||||
assert!(o.summary().contains("up to date"));
|
||||
}
|
||||
|
||||
// ── hashing ──
|
||||
|
||||
#[test]
|
||||
fn hashes_are_stable_and_content_sensitive() {
|
||||
assert_eq!(sha256_hex(b"abc"), sha256_hex(b"abc"));
|
||||
assert_ne!(sha256_hex(b"abc"), sha256_hex(b"abd"));
|
||||
assert_eq!(sha256_hex(b"").len(), 64);
|
||||
}
|
||||
|
||||
// ── verification gates installation ──
|
||||
|
||||
#[test]
|
||||
fn an_unsigned_pack_is_never_installed() {
|
||||
use ed25519_dalek::SigningKey;
|
||||
use hound_defs::{Indicator, Pack, Versions};
|
||||
|
||||
let dir = std::env::temp_dir().join(format!("hound-upd-{}", std::process::id()));
|
||||
let _ = std::fs::remove_dir_all(&dir);
|
||||
std::fs::create_dir_all(&dir).unwrap();
|
||||
|
||||
let real = SigningKey::from_bytes(&[1u8; 32]);
|
||||
let attacker = SigningKey::from_bytes(&[2u8; 32]);
|
||||
let p = Pack {
|
||||
version: "9999.99.99".into(),
|
||||
created: "2026-01-01T00:00:00Z".into(),
|
||||
sources: vec![],
|
||||
indicators: vec![Indicator {
|
||||
ecosystem: "npm".into(),
|
||||
name: "sudo".into(),
|
||||
versions: Versions::All,
|
||||
id: "MAL-EVIL".into(),
|
||||
summary: "would make Hound quarantine sudo".into(),
|
||||
}],
|
||||
};
|
||||
let forged = pack::sign(&p, &attacker, "hound-2026").unwrap();
|
||||
let trusted = [("hound-2026", real.verifying_key())];
|
||||
|
||||
// The exact check the updater performs before writing anything.
|
||||
assert!(
|
||||
pack::verify(&forged, &trusted).is_err(),
|
||||
"a pack signed by the wrong key must never reach the defs directory"
|
||||
);
|
||||
let _ = std::fs::remove_dir_all(&dir);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn refuses_to_run_with_an_empty_trust_store() {
|
||||
let dir = std::env::temp_dir().join(format!("hound-upd-nokey-{}", std::process::id()));
|
||||
let e = run(&dir, &[]).unwrap_err();
|
||||
assert!(e.to_string().contains("no signing key"));
|
||||
}
|
||||
|
||||
// ── configuration ──
|
||||
|
||||
#[test]
|
||||
fn the_source_can_be_pointed_elsewhere_for_mirrors() {
|
||||
let _guard = crate::test_util::locked();
|
||||
std::env::remove_var("HOUNDD_DEFS_URL");
|
||||
assert_eq!(base_url(), "https://defs.houndav.com");
|
||||
std::env::set_var("HOUNDD_DEFS_URL", "http://mirror.internal/defs");
|
||||
assert_eq!(base_url(), "http://mirror.internal/defs");
|
||||
std::env::remove_var("HOUNDD_DEFS_URL");
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn limits_are_small_enough_to_be_a_real_bound() {
|
||||
// A definitions pack is a list of package names. These exist so a
|
||||
// broken or hostile server cannot fill a disk.
|
||||
assert!(MAX_PACK_BYTES <= 64 * 1024 * 1024);
|
||||
assert!(MAX_INDEX_BYTES <= 1024 * 1024);
|
||||
assert!(TIMEOUT_SECS <= 60);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn a_malformed_index_is_an_error_not_a_panic() {
|
||||
assert!(serde_json::from_slice::<Index>(b"{not json").is_err());
|
||||
// An index with no packs array is empty rather than fatal.
|
||||
let empty: Index = serde_json::from_slice(b"{}").unwrap();
|
||||
assert!(empty.packs.is_empty());
|
||||
}
|
||||
}
|
||||
BIN
dist/hound_0.1.0_amd64.deb
vendored
BIN
dist/hound_0.1.0_amd64.deb
vendored
Binary file not shown.
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Reference in a new issue