#285: seedTrustDialog refuses under memberHerdrSocket instead of seeding fleetd's own home
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seedTrustDialog gated only on isProvisionedWorktree(cwd) and, being static, could not
see memberHerdrSocketConfigured() — unlike its sibling writeCharterFile, which already
refuses the spawn when it cannot place a file where a different-uid member can read it.
Under memberHerdrSocket + configDir unset, seedTrustDialog wrote fleetd's OWN
~/.claude.json while believing it was seeding the member's, reintroducing the fleetd
#149 failure (interactive trust dialog, no fleet_reply, silent readiness timeout) for
this one config combination.

Makes seedTrustDialog an instance method so it can see memberHerdrSocketConfigured()
and memberGroup(), and applies writeCharterFile's "refuse, don't degrade" rule: under
memberHerdrSocket it now requires both configDir and worktreeGroup before touching any
file, naming exactly which is missing, and shares the written .claude.json group-
readable (rw-r-----) via a new shareTrustJsonWithGroup so the member's OS user can
actually open it. The memberHerdrSocket-absent path (today's only live mode) is
unchanged.
This commit is contained in:
Dai Ha
2026-09-04 10:55:35 +07:00
parent 66e5247b6d
commit 7e49c6eca2
2 changed files with 236 additions and 17 deletions
@@ -18,7 +18,9 @@ import java.io.UncheckedIOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.StandardCopyOption;
import java.nio.file.attribute.GroupPrincipal;
import java.nio.file.attribute.PosixFileAttributeView;
import java.nio.file.attribute.PosixFilePermissions;
import java.util.Arrays;
import java.util.EnumSet;
import java.util.List;
@@ -540,16 +542,65 @@ public final class ClaudeCodeLauncher extends HerdrPeerLauncher {
* itself is still lost, because there is no OS-level compare-and-swap on a plain file, only this
* cooperative narrowing of the gap.
*
* <p><b>fleetd #285: refuses under {@code memberHerdrSocket} rather than writing somewhere the
* member cannot read.</b> Under {@code memberHerdrSocket:} the member pane runs as a
* <em>different OS user with its own {@code $HOME}</em> — the same reason {@link
* #writeCharterFile} routes the role/reply charter under {@code worktreeRoot} instead of
* {@code java.io.tmpdir} and refuses the spawn when it cannot. This method has no equivalent
* relocation available: unlike the charter (fleetd's own content, free to place anywhere and
* hand to the peer via an argv flag), {@code .claude.json} is a file Claude Code looks up for
* ITSELF at a fixed location — {@code CLAUDE_CONFIG_DIR/.claude.json}, or else the member OS
* user's own {@code ~/.claude.json}, a path fleetd has no channel to learn. So when {@code
* configDir} is unset, there is no member-readable target to seed at all — writing the
* unqualified default would land in <em>fleetd's own</em> {@code ~/.claude.json} instead, the
* exact defect this fix closes, not a workable fallback. And even with {@code configDir} set,
* the file this method itself just wrote is {@code 0600} (owner-only — see {@link
* #copyPosixPermissionsIfPresent}), unreadable by a different-uid member unless shared with
* {@code worktreeGroup}, the same group {@link EnvAllowListScrub#shareWithGroup} already uses
* for the ZDOTDIR scrub (fleetd #213) and the charter file (fleetd #219/#222). So under {@code
* memberHerdrSocket} this method requires BOTH {@code configDir} and {@code worktreeGroup}
* before it ever touches a file, and refuses the spawn — naming exactly which one is missing —
* rather than silently corrupt fleetd's own home or hand the member an unreadable path. This
* mirrors {@link #writeCharterFile}'s "refuse, don't degrade" decision: a member spawned without
* a readable trust seed is not degraded, it sits on the interactive dialog forever and never
* calls {@code fleet_reply} — exactly the failure fleetd #149 exists to prevent, so trading it
* for "spawn something" is not worth it. When {@code configDir} and {@code worktreeGroup} are
* both present, the write proceeds exactly as below and the resulting file is additionally
* chgrp'd/chmod'd group-readable ({@code rw-r-----}) via {@link
* #shareTrustJsonWithGroup(Path, String)} so the member's OS user can actually open it — the
* directory itself (unlike {@code worktreeRoot} or the charter's per-spawn directory) is not
* fleetd-managed, so its own traversal permissions remain the operator's setup, same as they
* already must be for the member to read anything else fleetd points {@code CLAUDE_CONFIG_DIR}
* at. With {@code memberHerdrSocket} ABSENT (today's only live mode) every branch below is
* byte-identical to before this fix.
*
* @param configDir the profile's {@code CLAUDE_CONFIG_DIR} ({@code cfg.configDir()}), or
* {@code null}/blank to target the default {@code ~/.claude.json}
* {@code null}/blank to target the default {@code ~/.claude.json} — refused
* outright when {@code memberHerdrSocket} is configured, see above
* @param cwd the spawn's resolved working directory — the exact key Claude Code will look
* up for itself once it starts there
* @throws IllegalStateException when {@code memberHerdrSocket} is configured but {@code
* configDir} and/or {@code worktreeGroup} is not — the same
* refusal shape as {@link #writeCharterFile}
*/
private static void seedTrustDialog(String configDir, String cwd) {
private void seedTrustDialog(String configDir, String cwd) {
if (!isProvisionedWorktree(cwd)) {
return;
}
boolean unsetConfigDir = configDir == null || configDir.isBlank();
boolean memberHerdrSocket = memberHerdrSocketConfigured();
String group = memberHerdrSocket ? memberGroup() : null;
if (memberHerdrSocket && (unsetConfigDir || group == null)) {
throw new IllegalStateException("memberHerdrSocket is configured, so the workspace-trust "
+ "seed (.claude.json, which gates Claude Code's interactive trust dialog) must be "
+ "placed where the member's OS user can read it — configDir, shared via "
+ "worktreeGroup — but " + (unsetConfigDir ? "configDir" : "worktreeGroup")
+ " is not configured. Refusing to spawn rather than write fleetd's own default "
+ "'~/.claude.json' or hand the member a config file it cannot read: that member "
+ "would sit on the interactive trust dialog forever and never reach an "
+ "injectable state. Configure configDir on this profile and worktreeGroup on the "
+ "fleet to enable claude-code member spawns under memberHerdrSocket.");
}
Path target = unsetConfigDir
? Path.of(System.getProperty("user.home"), ".claude.json")
: Path.of(configDir, ".claude.json");
@@ -559,18 +610,20 @@ public final class ClaudeCodeLauncher extends HerdrPeerLauncher {
// profile that simply forgot to set configDir gets no signal at all short of the
// operator noticing their own file changing. Say so loudly, every time it is about to
// happen, rather than only once ever: each occurrence is a live write to a real
// person's home config and deserves its own log line.
// person's home config and deserves its own log line. (Reached only when
// memberHerdrSocket is absent — the block above already refused otherwise.)
log.warn("seedTrustDialog: profile has no configDir set, so the workspace-trust seed "
+ "for cwd '{}' is about to write the operator's own default '{}' — set "
+ "configDir on this profile to target a per-member config file instead",
cwd, target);
}
synchronized (TRUST_JSON_LOCK) {
boolean written = false;
try {
if (target.getParent() != null) {
Files.createDirectories(target.getParent());
}
for (int attempt = 1; attempt <= MAX_TRUST_JSON_CAS_ATTEMPTS; attempt++) {
for (int attempt = 1; attempt <= MAX_TRUST_JSON_CAS_ATTEMPTS && !written; attempt++) {
byte[] before = Files.isRegularFile(target) ? Files.readAllBytes(target) : null;
ObjectNode root = parseTrustJsonOrEmpty(before);
JsonNode projectsNode = root.get("projects");
@@ -611,23 +664,67 @@ public final class ClaudeCodeLauncher extends HerdrPeerLauncher {
continue;
}
writeAtomically(target, newContent);
return;
written = true;
}
if (!written) {
// fleetd #247: deliberately do NOT write here. A member that starts without the
// seed still starts — it may hit the trust dialog fleetd #149 describes and fail
// to reach an injectable state, but that failure is visible (herdr reports it,
// the spawn-readiness gate times out) and recoverable (retry the spawn). Writing
// our stale copy over whatever the other writer left would be silent and, if that
// other writer is the operator's own live session, could destroy real
// configuration — fail toward the recoverable outcome, not the silent one.
log.warn("seedTrustDialog: gave up seeding workspace-trust for cwd '{}' into '{}' "
+ "after {} attempts — another writer (most plausibly the operator's own "
+ "live Claude Code sharing this file) kept changing it faster than we "
+ "could re-read it, so nothing was written; the member may show the "
+ "trust dialog instead", cwd, target, MAX_TRUST_JSON_CAS_ATTEMPTS);
}
// fleetd #247: deliberately do NOT write here. A member that starts without the
// seed still starts — it may hit the trust dialog fleetd #149 describes and fail to
// reach an injectable state, but that failure is visible (herdr reports it, the
// spawn-readiness gate times out) and recoverable (retry the spawn). Writing our
// stale copy over whatever the other writer left would be silent and, if that other
// writer is the operator's own live session, could destroy real configuration —
// fail toward the recoverable outcome, not the silent one.
log.warn("seedTrustDialog: gave up seeding workspace-trust for cwd '{}' into '{}' "
+ "after {} attempts — another writer (most plausibly the operator's own "
+ "live Claude Code sharing this file) kept changing it faster than we could "
+ "re-read it, so nothing was written; the member may show the trust dialog "
+ "instead", cwd, target, MAX_TRUST_JSON_CAS_ATTEMPTS);
} catch (Exception e) {
log.debug("cannot seed workspace-trust entry for cwd '{}' into '{}'", cwd, target, e);
return;
}
// fleetd #285: the write above lands as fleetd's own OS user; under memberHerdrSocket
// that is NOT the member's OS user, so without this the member still cannot read the
// file it exists to seed — a silent readiness timeout with the write looking "done".
// Deliberately OUTSIDE the swallow-all catch above: a group that fails to resolve here
// means the seed is unreadable despite a successful write, which must fail as loudly as
// writeCharterFile's own EnvAllowListScrub.shareWithGroup call already does.
if (written && memberHerdrSocket) {
shareTrustJsonWithGroup(target, group);
}
}
}
/**
* fleetd #285: chgrp + chmod {@code target} — a {@code .claude.json} this method just wrote as
* fleetd's own OS user — group-readable ({@code rw-r-----}) for {@code group}, so a member OS
* user under {@code memberHerdrSocket} can open it. Mirrors {@link
* EnvAllowListScrub#shareWithGroup}'s per-file mode exactly (read-only for the group — a member
* never needs to write this file itself), but touches only the FILE, never its parent
* directory: unlike {@code worktreeRoot} or the charter's per-spawn directory, {@code
* configDir} is not a directory fleetd creates or owns, so its traversal permissions are left to
* the operator's own setup, same as they already must be for the member to read anything else
* fleetd points {@code CLAUDE_CONFIG_DIR} at.
*
* @throws UncheckedIOException when {@code group} does not resolve on this host, or a
* group-ownership/permission call is refused — the file was written
* but is not usable by the member, and that must be loud
*/
private static void shareTrustJsonWithGroup(Path target, String group) {
try {
GroupPrincipal principal = target.getFileSystem().getUserPrincipalLookupService()
.lookupPrincipalByGroupName(group);
PosixFileAttributeView view = Files.getFileAttributeView(target, PosixFileAttributeView.class);
if (view == null) {
throw new IOException("POSIX file attributes are not supported for " + target);
}
view.setGroup(principal);
Files.setPosixFilePermissions(target, PosixFilePermissions.fromString("rw-r-----"));
} catch (IOException e) {
throw new UncheckedIOException("cannot share workspace-trust file " + target + " with "
+ "group '" + group + "' — the group must exist, and the fleetd operator ("
+ System.getProperty("user.name") + ") must be a member of it", e);
}
}
@@ -2742,4 +2742,126 @@ class ClaudeCodeLauncherTest {
"a WARN naming the cwd must fire when the profile sets no configDir: "
+ appender.list.stream().map(ILoggingEvent::getFormattedMessage).toList());
}
// --- fleetd #285: seedTrustDialog under memberHerdrSocket --------------------------------------
//
// seedTrustDialog gated only on isProvisionedWorktree(cwd) and, being static, could not see
// memberHerdrSocketConfigured() at all — unlike its sibling writeCharterFile one method below,
// which already refuses the spawn when it cannot place the charter where a different-uid member
// can read it. Under memberHerdrSocket + configDir unset, seedTrustDialog wrote fleetd's OWN
// ~/.claude.json (the operator's real file) while believing it was seeding the member's. The fix
// makes the method an instance method so it can see memberHerdrSocketConfigured(), and applies
// the same "refuse, don't silently write somewhere wrong" rule writeCharterFile already uses.
@Test
void seedTrustDialogUnderMemberHerdrSocketSharesTheFileWithTheConfiguredGroup(
@TempDir Path configDir, @TempDir Path worktree, @TempDir Path worktreeRoot) throws Exception {
markAsProvisionedWorktree(worktree);
String group = currentUserGroup();
FakeHerdr herdr = new FakeHerdr();
// trustProfile always sets a bridge mcpUrl, so a reply charter is generated too, which
// means writeCharterFile ALSO runs under memberHerdrSocket and needs its own worktreeRoot —
// pass one so this test isolates the trust-seed behaviour instead of tripping that refusal.
FleetConfig.Profile cfg = trustProfile(configDir.toString(), worktree.toString());
serviceWithConfig(herdr, cfg, () -> configWithMemberHerdrSocket(worktreeRoot.toString(), group)).spawn();
Path claudeJson = configDir.resolve(".claude.json");
assertTrue(Files.exists(claudeJson), "still seeded into <configDir>/.claude.json under memberHerdrSocket");
JsonNode project = new ObjectMapper().readTree(claudeJson.toFile())
.path("projects").path(worktree.toString());
assertTrue(project.path("hasTrustDialogAccepted").asBoolean(false));
assertEquals("rw-r-----", PosixFilePermissions.toString(Files.getPosixFilePermissions(claudeJson)),
"under memberHerdrSocket the file must be shared group-readable, mirroring the "
+ "charter file's own per-file mode (fleetd #222) — a 0600 file (Claude "
+ "Code's own default) is unreadable by the member's different OS user");
String actualGroup = Files.getFileAttributeView(claudeJson, PosixFileAttributeView.class)
.readAttributes().group().getName();
assertEquals(group, actualGroup, "the file must be chgrp'd to the configured worktreeGroup");
}
/**
* The bug itself: {@code memberHerdrSocket} configured, {@code configDir} unset. Before the fix
* this wrote fleetd's own default {@code ~/.claude.json} (here redirected to {@code fakeHome} so
* a reintroduced bug still cannot touch the real operator file); after the fix it must refuse the
* spawn instead, naming {@code configDir} as the missing key, before the member is ever started.
*/
@Test
void seedTrustDialogUnderMemberHerdrSocketRefusesWhenConfigDirUnset(
@TempDir Path fakeHome, @TempDir Path worktree) throws Exception {
markAsProvisionedWorktree(worktree);
String originalHome = System.getProperty("user.home");
System.setProperty("user.home", fakeHome.toString());
try {
FakeHerdr herdr = new FakeHerdr();
FleetConfig.Profile cfg = trustProfile(null, worktree.toString());
ClaudeCodeLauncher launcher = serviceWithConfig(herdr, cfg,
() -> configWithMemberHerdrSocket(null, "some-group"));
IllegalStateException ex = assertThrows(IllegalStateException.class, launcher::spawn,
"memberHerdrSocket + no configDir must refuse the spawn, not write fleetd's own "
+ "default ~/.claude.json");
assertTrue(ex.getMessage().contains("configDir"),
"the refusal must name the missing config key — got: " + ex.getMessage());
assertFalse(Files.exists(fakeHome.resolve(".claude.json")),
"nothing may be written to fleetd's own default home — this is the exact fleetd "
+ "#285 defect: writing the operator's own home instead of the member's");
assertFalse(herdr.called("agent.start"),
"the spawn must be refused BEFORE the member is ever started — got calls: " + herdr.calls);
} finally {
System.setProperty("user.home", originalHome);
}
}
/**
* {@code configDir} alone is not enough — without {@code worktreeGroup} the file fleetd writes
* stays {@code 0600} and the member's different OS user still cannot read it, so this must also
* refuse, naming {@code worktreeGroup} this time.
*/
@Test
void seedTrustDialogUnderMemberHerdrSocketRefusesWhenWorktreeGroupUnset(
@TempDir Path configDir, @TempDir Path worktree) throws Exception {
markAsProvisionedWorktree(worktree);
FakeHerdr herdr = new FakeHerdr();
FleetConfig.Profile cfg = trustProfile(configDir.toString(), worktree.toString());
ClaudeCodeLauncher launcher = serviceWithConfig(herdr, cfg,
() -> configWithMemberHerdrSocket(null, null));
IllegalStateException ex = assertThrows(IllegalStateException.class, launcher::spawn,
"memberHerdrSocket + no worktreeGroup must refuse the spawn, not write an unreadable file");
assertTrue(ex.getMessage().contains("worktreeGroup"),
"configDir alone is not enough — got: " + ex.getMessage());
assertFalse(Files.exists(configDir.resolve(".claude.json")),
"nothing may be written when the file cannot be shared with the member's group");
assertFalse(herdr.called("agent.start"),
"the spawn must be refused BEFORE the member is ever started");
}
/**
* Regression proof: with {@code memberHerdrSocket} ABSENT — even given a LIVE, non-null {@code
* config} supplier (not merely {@code config == null}, which every other seedTrustDialog test in
* this file already exercises) — the write must stay byte-identical to before this fix: existing
* {@code 0600} permissions preserved, no chgrp/chmod attempted. This is the proof the ticket asks
* for: the path the whole live fleet uses today is unchanged by this fix.
*/
@Test
void seedTrustDialogPreservesExisting0600PermissionsWhenMemberHerdrSocketAbsentEvenWithALiveConfigSupplier(
@TempDir Path configDir, @TempDir Path worktree) throws Exception {
markAsProvisionedWorktree(worktree);
Path claudeJson = configDir.resolve(".claude.json");
Files.writeString(claudeJson, "{}");
assumeTrue(Files.getFileAttributeView(claudeJson, PosixFileAttributeView.class) != null,
"no POSIX permissions on this filesystem — skipping rather than failing");
Files.setPosixFilePermissions(claudeJson, PosixFilePermissions.fromString("rw-------"));
FakeHerdr herdr = new FakeHerdr();
FleetConfig.Profile cfg = trustProfile(configDir.toString(), worktree.toString());
FleetConfig config = new FleetConfig(null, null, null, Map.of(), null, null, null, null, null,
null, null, null, null, null, null, null, null, null, null, null, null, null).withDefaults();
serviceWithConfig(herdr, cfg, () -> config).spawn();
assertEquals("rw-------", PosixFilePermissions.toString(Files.getPosixFilePermissions(claudeJson)),
"with memberHerdrSocket absent — even given a live config supplier — the seed must "
+ "stay byte-identical to before this fix: no chgrp/chmod attempted");
}
}