Files
PiCloud/crates/executor-core/src/sdk/secrets.rs
MechaCat02 bdcd3dc7f4 fix(executor): bound Rhai→JSON materialization to prevent anonymous OOM
The per-element Rhai sandbox caps (max_string_size 64 KiB, max_array_size /
max_map_size 10 000) do NOT bound the *materialized* size: Rhai shares strings
and arrays by Rc, so a 10 000-element array of one aliased 64 KiB string is
cheap to build (~10 000 ops, far under the 1 M op budget) yet dealiases to
~640 MiB of distinct JSON. Every Dynamic→JSON conversion deep-copies the
aliases; the HTTP response body path had NO size cap at all, and the KV/docs
value caps run only AFTER full materialization — so a handful of anonymous
requests could OOM the node (32 concurrent × ~640 MiB ≈ 20 GiB) on the stated
consumer-hardware target.

Add a byte-budgeted materializer that bails the moment the budget is exceeded,
so the transient allocation is bounded regardless of aliasing:
- bridge.rs: `dynamic_to_json_capped(value, max) -> Result<Json, JsonSizeError>`
  (charges a running budget) + `MAX_JSON_MATERIALIZE_BYTES` (16 MiB hard rail,
  far above the 256 KiB business caps). `dynamic_to_json` stays infallible for
  best-effort paths (logging) but is now internally bounded — it collapses an
  over-limit value to a marker string instead of OOMing.
- Route every user-value boundary through the fail-closed capped form: KV
  set/set_if (+ the CAS `expected`), docs create/update/find, secrets set,
  http request body, workflow input, `json::stringify`, and the HTTP RESPONSE
  body (previously the one fully-uncapped exit → now a 500). `invoke` args and
  the pubsub/queue message materializers get the same byte budget in place.
- `impl From<JsonSizeError> for Box<EvalAltResult>` so SDK sites protect
  themselves with a bare `?`.

Pinned by bridge unit tests: an aliased 10 000×64 KiB array errors on the
budget rather than materializing, and the infallible wrapper yields a marker
instead of OOMing. Workspace 914 + journeys 157/157 green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-13 21:50:16 +02:00

129 lines
4.5 KiB
Rust

//! `secrets::` Rhai bridge — encrypted per-app secrets (v1.1.7).
//!
//! ```rhai
//! secrets::set("stripe_key", "sk_live_xxx");
//! secrets::set("oauth", #{ client_id: "abc", client_secret: "xyz" });
//! let key = secrets::get("stripe_key"); // value or ()
//! let removed = secrets::delete("stripe_key"); // bool
//! let page = secrets::list(#{ cursor: (), limit: 100 });
//! // page = #{ names: [...], next_cursor: () | "..." }
//! ```
//!
//! Collection-less (secrets are per-app, like pubsub topics) so there's
//! no `::collection(...)`. Values are any JSON-serializable Rhai value
//! (String/Map/Array/number/bool); a String round-trips back as a
//! String. `app_id` is derived from `cx.app_id` in the service — it
//! never appears in the script-side signature, preserving cross-app
//! isolation.
use std::sync::Arc;
use picloud_shared::{SdkCallCx, SecretsListPage, Services};
use rhai::{Array, Dynamic, Engine as RhaiEngine, EvalAltResult, Map, Module};
use super::bridge::{
block_on, dynamic_to_json_capped, json_to_dynamic, runtime_err, MAX_JSON_MATERIALIZE_BYTES,
};
pub(super) fn register(engine: &mut RhaiEngine, services: &Services, cx: Arc<SdkCallCx>) {
let svc = services.secrets.clone();
let mut module = Module::new();
// secrets::set(name, value) — overwrites if present.
{
let svc = svc.clone();
let cx = cx.clone();
module.set_native_fn(
"set",
move |name: &str, value: Dynamic| -> Result<(), Box<EvalAltResult>> {
let json = dynamic_to_json_capped(&value, MAX_JSON_MATERIALIZE_BYTES)?;
let svc = svc.clone();
let cx = cx.clone();
block_on("secrets", async move { svc.set(&cx, name, json).await })
},
);
}
// secrets::get(name) — decoded value, or () if missing.
{
let svc = svc.clone();
let cx = cx.clone();
module.set_native_fn(
"get",
move |name: &str| -> Result<Dynamic, Box<EvalAltResult>> {
let svc = svc.clone();
let cx = cx.clone();
let opt = block_on("secrets", async move { svc.get(&cx, name).await })?;
Ok(opt.map_or(Dynamic::UNIT, json_to_dynamic))
},
);
}
// secrets::delete(name) — bool was-present.
{
let svc = svc.clone();
let cx = cx.clone();
module.set_native_fn(
"delete",
move |name: &str| -> Result<bool, Box<EvalAltResult>> {
let svc = svc.clone();
let cx = cx.clone();
block_on("secrets", async move { svc.delete(&cx, name).await })
},
);
}
// secrets::list(#{ cursor, limit }) — names only, cursor-paginated.
{
let svc = svc.clone();
let cx = cx.clone();
module.set_native_fn(
"list",
move |opts: Map| -> Result<Map, Box<EvalAltResult>> {
let (cursor, limit) = parse_list_opts(&opts)?;
let svc = svc.clone();
let cx = cx.clone();
let page: SecretsListPage = block_on("secrets", async move {
svc.list(&cx, cursor.as_deref(), limit).await
})?;
Ok(list_page_to_map(page))
},
);
}
engine.register_static_module("secrets", module.into());
}
/// Pull `cursor` (string or `()`) and `limit` (int or `()`) out of the
/// options map. Unknown/extra keys are ignored.
fn parse_list_opts(opts: &Map) -> Result<(Option<String>, u32), Box<EvalAltResult>> {
let cursor = match opts.get("cursor") {
None => None,
Some(d) if d.is_unit() => None,
Some(d) if d.is_string() => Some(d.clone().into_string().unwrap_or_default()),
Some(_) => return Err(runtime_err("secrets::list: cursor must be a string or ()")),
};
let limit = match opts.get("limit") {
None => 0,
Some(d) if d.is_unit() => 0,
Some(d) => {
let n = d
.as_int()
.map_err(|_| runtime_err("secrets::list: limit must be an integer or ()"))?;
u32::try_from(n.max(0)).unwrap_or(u32::MAX)
}
};
Ok((cursor, limit))
}
fn list_page_to_map(page: SecretsListPage) -> Map {
let mut m = Map::new();
let names: Array = page.names.into_iter().map(Dynamic::from).collect();
m.insert("names".into(), names.into());
m.insert(
"next_cursor".into(),
page.next_cursor.map_or(Dynamic::UNIT, Dynamic::from),
);
m
}