From a655a0f3e4201840eda94938fc8d6222c2b94a99 Mon Sep 17 00:00:00 2001
From: Leo K <crowlkats@toaxl.com>
Date: Mon, 13 Sep 2021 19:26:23 +0200
Subject: [PATCH] feat(unstable): allow specifing gid and uid for subprocess
 (#11586)

---
 cli/dts/lib.deno.ns.d.ts       |  6 ++++
 cli/dts/lib.deno.unstable.d.ts |  4 +++
 cli/tests/unit/process_test.ts | 56 ++++++++++++++++++++++++++++++++++
 runtime/js/40_process.js       |  4 +++
 runtime/ops/process.rs         | 20 ++++++++++++
 5 files changed, 90 insertions(+)

diff --git a/cli/dts/lib.deno.ns.d.ts b/cli/dts/lib.deno.ns.d.ts
index 5b6849bfd8..05e600ed76 100644
--- a/cli/dts/lib.deno.ns.d.ts
+++ b/cli/dts/lib.deno.ns.d.ts
@@ -2034,6 +2034,12 @@ declare namespace Deno {
    * Environmental variables for subprocess can be specified using `opt.env`
    * mapping.
    *
+   * `opt.uid` sets the child process’s user ID. This translates to a setuid call
+   * in the child process. Failure in the setuid call will cause the spawn to fail.
+   *
+   * `opt.gid` is similar to `opt.uid`, but sets the group ID of the child process.
+   * This has the same semantics as the uid field.
+   *
    * By default subprocess inherits stdio of parent process. To change that
    * `opt.stdout`, `opt.stderr` and `opt.stdin` can be specified independently -
    * they can be set to either an rid of open file or set to "inherit" "piped"
diff --git a/cli/dts/lib.deno.unstable.d.ts b/cli/dts/lib.deno.unstable.d.ts
index 5854a51812..1a27f2b389 100644
--- a/cli/dts/lib.deno.unstable.d.ts
+++ b/cli/dts/lib.deno.unstable.d.ts
@@ -713,8 +713,12 @@ declare namespace Deno {
   export function run<
     T extends RunOptions & {
       clearEnv?: boolean;
+      gid?: number;
+      uid?: number;
     } = RunOptions & {
       clearEnv?: boolean;
+      gid?: number;
+      uid?: number;
     },
   >(opt: T): Process<T>;
 
diff --git a/cli/tests/unit/process_test.ts b/cli/tests/unit/process_test.ts
index 371521e332..9f8e9cd9fc 100644
--- a/cli/tests/unit/process_test.ts
+++ b/cli/tests/unit/process_test.ts
@@ -537,3 +537,59 @@ unitTest(
     p.close();
   },
 );
+
+unitTest(
+  { perms: { run: true, read: true }, ignore: Deno.build.os === "windows" },
+  async function uid(): Promise<void> {
+    const p = Deno.run({
+      cmd: [
+        "id",
+        "-u",
+      ],
+      stdout: "piped",
+    });
+
+    const currentUid = new TextDecoder().decode(await p.output());
+    p.close();
+
+    if (currentUid !== "0") {
+      assertThrows(() => {
+        Deno.run({
+          cmd: [
+            "echo",
+            "fhqwhgads",
+          ],
+          uid: 0,
+        });
+      }, Deno.errors.PermissionDenied);
+    }
+  },
+);
+
+unitTest(
+  { perms: { run: true, read: true }, ignore: Deno.build.os === "windows" },
+  async function gid(): Promise<void> {
+    const p = Deno.run({
+      cmd: [
+        "id",
+        "-g",
+      ],
+      stdout: "piped",
+    });
+
+    const currentGid = new TextDecoder().decode(await p.output());
+    p.close();
+
+    if (currentGid !== "0") {
+      assertThrows(() => {
+        Deno.run({
+          cmd: [
+            "echo",
+            "fhqwhgads",
+          ],
+          gid: 0,
+        });
+      }, Deno.errors.PermissionDenied);
+    }
+  },
+);
diff --git a/runtime/js/40_process.js b/runtime/js/40_process.js
index 543c53c271..782dfe4764 100644
--- a/runtime/js/40_process.js
+++ b/runtime/js/40_process.js
@@ -102,6 +102,8 @@
     cwd = undefined,
     clearEnv = false,
     env = {},
+    gid = undefined,
+    uid = undefined,
     stdout = "inherit",
     stderr = "inherit",
     stdin = "inherit",
@@ -114,6 +116,8 @@
       cwd,
       clearEnv,
       env: ObjectEntries(env),
+      gid,
+      uid,
       stdin: isRid(stdin) ? "" : stdin,
       stdout: isRid(stdout) ? "" : stdout,
       stderr: isRid(stderr) ? "" : stderr,
diff --git a/runtime/ops/process.rs b/runtime/ops/process.rs
index b47492e58e..e40a15b4bc 100644
--- a/runtime/ops/process.rs
+++ b/runtime/ops/process.rs
@@ -63,6 +63,8 @@ pub struct RunArgs {
   cwd: Option<String>,
   clear_env: bool,
   env: Vec<(String, String)>,
+  gid: Option<u32>,
+  uid: Option<u32>,
   stdin: String,
   stdout: String,
   stderr: String,
@@ -123,6 +125,24 @@ fn op_run(
     c.env(key, value);
   }
 
+  #[cfg(unix)]
+  if let Some(gid) = run_args.gid {
+    super::check_unstable(state, "Deno.run.gid");
+    c.gid(gid);
+  }
+  #[cfg(unix)]
+  if let Some(uid) = run_args.uid {
+    super::check_unstable(state, "Deno.run.uid");
+    c.uid(uid);
+  }
+  #[cfg(unix)]
+  unsafe {
+    c.pre_exec(|| {
+      libc::setgroups(0, std::ptr::null());
+      Ok(())
+    });
+  }
+
   // TODO: make this work with other resources, eg. sockets
   if !run_args.stdin.is_empty() {
     c.stdin(subprocess_stdio_map(run_args.stdin.as_ref())?);