Merge CB-606: refuse an unrecognized auth.mode or placement at config load

Three fields had CB-604's shape — lower-cased, compared against one string,
never checked against the valid set. The auth.mode one was the worst: a typo of
'token' silently behaved as loopback-trust, and validateAuthExposure() only fires
on a non-loopback bind, so a loopback bind hid it end to end. The daemon started
clean and authenticated nobody while the operator believed token mode was on.

All three now refuse at config load, naming the value and the accepted set. The
top-level placement policy was already validated but only lazily at first spawn;
it now calls PlacementPolicies.fromName eagerly at load, so a bad name cannot
start a daemon that merely looks healthy.

Verified by probing the real BridgedConfig.load with eleven values, including the
critical auth.mode typo on a loopback bind, and by loading the live gitignored
bridged.yaml — which the worker cannot see and so could not check.

Closes #106

bridged/src/main/java/dev/ltms/bridged/config/BridgedConfig.java

@@ -7,6 +7,7 @@ import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
 import dev.ltms.bridged.msg.AmqpReplyInbox;
 import dev.ltms.bridged.peer.MemberRole;
+import dev.ltms.bridged.placement.PlacementPolicies;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -987,7 +988,13 @@ public record BridgedConfig(
             rejectDuplicateMemberSlots(yaml);
             rejectNegativeMaxLoad(yaml);
             rejectUnknownKind(yaml);
+            rejectUnknownAuthMode(yaml);
+            rejectUnknownPlacement(yaml);
             BridgedConfig cfg = YAML.readValue(yaml, BridgedConfig.class);
+            // CB-606: validated here, eagerly, using PlacementPolicies.fromName as the single source
+            // of truth — not lazily at first spawn (see CompositePeerLauncher's placementPolicy
+            // Supplier), where a bad name would still start a daemon that looks healthy.
+            rejectUnknownPlacementPolicy(cfg.placement());
             return cfg.withDefaults();
         } catch (IOException e) {
             throw new UncheckedIOException("cannot read bridged config at " + path, e);
@@ -1328,6 +1335,115 @@ public record BridgedConfig(
         }
     }
 
+    /** The auth modes this build understands — {@link Auth#mode()}'s only valid values. */
+    private static final Set<String> KNOWN_AUTH_MODES = Set.of(Auth.MODE_LOOPBACK_TRUST, Auth.MODE_TOKEN);
+
+    /**
+     * Reject an {@code auth.mode} that is not one of {@link #KNOWN_AUTH_MODES} (CB-606), naming the
+     * value and the accepted set.
+     *
+     * <p>{@link Auth}'s compact constructor only lower-cases {@code mode}, and
+     * {@link Auth#tokenMode()} only compares the result against {@code MODE_TOKEN} — anything else,
+     * including a typo like {@code toekn}, silently behaves as {@code loopback-trust}. That fallback
+     * is otherwise checked only by {@link #validateAuthExposure()}, and only when the bind is
+     * non-loopback: on a loopback bind (the common case) the typo is invisible end to end — the
+     * daemon starts cleanly and authenticates nobody while the operator believes {@code token} mode
+     * is active. Refuse it here, unconditionally, at config load, rather than let it hide behind the
+     * bind check.
+     *
+     * @param yaml the raw config text
+     * @throws IllegalStateException when {@code auth.mode} is a non-blank value not in
+     *                                {@link #KNOWN_AUTH_MODES} (case-insensitive)
+     */
+    static void rejectUnknownAuthMode(String yaml) {
+        Map<?, ?> raw;
+        try {
+            raw = YAML.readValue(yaml, Map.class);
+        } catch (IOException | IllegalArgumentException e) {
+            return; // a malformed file is reported by the real parse, not here
+        }
+        if (raw == null || !(raw.get("auth") instanceof Map<?, ?> auth)) {
+            return;
+        }
+        if (!(auth.get("mode") instanceof String mode) || mode.isBlank()
+                || KNOWN_AUTH_MODES.contains(mode.toLowerCase())) {
+            return;
+        }
+        throw new IllegalStateException("refusing to start: auth.mode=" + mode
+                + " is not recognized — accepted values are "
+                + String.join(", ", KNOWN_AUTH_MODES.stream().sorted().toList())
+                + " (case-insensitive); an unrecognized mode would otherwise silently fall back to"
+                + " loopback-trust, which authenticates nobody.");
+    }
+
+    /** The per-profile placements this build understands — {@link Profile#placement()}'s only valid values. */
+    private static final Set<String> KNOWN_PLACEMENTS = Set.of("tab", "pane");
+
+    /**
+     * Reject a profile whose {@code placement:} is not one of {@link #KNOWN_PLACEMENTS} (CB-606),
+     * naming the profile, the value it set, and the accepted set.
+     *
+     * <p>{@link Profile}'s compact constructor only lower-cases {@code placement}, and
+     * {@link Profile#tabPlacement()} only compares the result against {@code "tab"} — anything else,
+     * including a typo like {@code tabb}, silently falls back to the legacy pane placement with no
+     * signal anywhere.
+     *
+     * @param yaml the raw config text
+     * @throws IllegalStateException when any profile's {@code placement} is a non-blank value not in
+     *                                {@link #KNOWN_PLACEMENTS} (case-insensitive)
+     */
+    static void rejectUnknownPlacement(String yaml) {
+        Map<?, ?> raw;
+        try {
+            raw = YAML.readValue(yaml, Map.class);
+        } catch (IOException | IllegalArgumentException e) {
+            return; // a malformed file is reported by the real parse, not here
+        }
+        if (raw == null || !(raw.get("profiles") instanceof Map<?, ?> profiles)) {
+            return;
+        }
+        List<String> bad = profiles.entrySet().stream()
+                .filter(e -> e.getValue() instanceof Map<?, ?> p
+                        && p.get("placement") instanceof String pl && !pl.isBlank()
+                        && !KNOWN_PLACEMENTS.contains(pl.toLowerCase()))
+                .map(e -> String.valueOf(e.getKey()) + "=" + ((Map<?, ?>) e.getValue()).get("placement"))
+                .sorted()
+                .toList();
+        if (!bad.isEmpty()) {
+            throw new IllegalStateException("refusing to start: profile(s) [" + String.join(", ", bad)
+                    + "] set an unrecognized placement — accepted values are "
+                    + String.join(", ", KNOWN_PLACEMENTS.stream().sorted().toList())
+                    + " (case-insensitive); an unrecognized placement would otherwise fall back to"
+                    + " legacy pane placement with no signal anywhere.");
+        }
+    }
+
+    /**
+     * Reject a top-level {@code placement:} policy name {@link PlacementPolicies#fromName} does not
+     * recognize (CB-606), at config load rather than lazily at first spawn.
+     *
+     * <p>{@code CompositePeerLauncher} only calls {@link PlacementPolicies#fromName} per spawn,
+     * through a {@code Supplier} that re-reads live config (CB-559, so a hot-reloaded placement
+     * policy takes effect without a restart) — so a bad name still starts a daemon that looks
+     * healthy and fails only the first time something spawns without naming a profile. Every other
+     * field this class validates fails here, at load; this one gets the same treatment, calling
+     * {@link PlacementPolicies#fromName} itself as the single source of truth for what is valid
+     * rather than duplicating its accepted set.
+     *
+     * @param placement the raw, possibly null/blank {@code placement} value as parsed (before
+     *                   {@link #withDefaults()} runs); {@code fromName} itself treats null/blank as
+     *                   {@code fixed}, so this call changes no default
+     * @throws IllegalStateException when {@code placement} is a name {@link PlacementPolicies} does
+     *                                not recognize
+     */
+    private static void rejectUnknownPlacementPolicy(String placement) {
+        try {
+            PlacementPolicies.fromName(placement);
+        } catch (IllegalArgumentException e) {
+            throw new IllegalStateException("refusing to start: " + e.getMessage(), e);
+        }
+    }
+
     static List<String> unknownTopLevelKeys(String yaml) {
         Map<?, ?> raw;
         try {

bridged/src/test/java/dev/ltms/bridged/config/BridgedConfigTest.java

@@ -1407,6 +1407,89 @@ class BridgedConfigTest {
         assertTrue(e.getMessage().contains("maxLoad"), "error names the key: " + e.getMessage());
     }
 
+    /**
+     * CB-606: an unrecognized {@code auth.mode} used to silently fall back to
+     * {@code loopback-trust} — {@link BridgedConfig.Auth#tokenMode()} only checked equality
+     * against {@code "token"}. On a loopback bind {@link BridgedConfig#validateAuthExposure()}
+     * never runs (it only fires for a non-loopback bind), so the typo was completely invisible:
+     * the daemon started cleanly and authenticated nobody while the operator believed token mode
+     * was active.
+     */
+    @Test
+    void unknownAuthModeIsRefusedAtLoadNamingTheValueAndTheAcceptedSet(@TempDir Path dir) throws Exception {
+        Path f = dir.resolve("auth-mode-typo.yaml");
+        Files.writeString(f, """
+                bind:
+                  host: 127.0.0.1
+                  port: 8765
+                auth:
+                  mode: toekn
+                """);
+
+        IllegalStateException e = assertThrows(IllegalStateException.class, () -> BridgedConfig.load(f));
+        assertTrue(e.getMessage().contains("toekn"), "error names the bad value: " + e.getMessage());
+        assertTrue(e.getMessage().contains("loopback-trust") && e.getMessage().contains("token"),
+                "error names the accepted set: " + e.getMessage());
+    }
+
+    /**
+     * CB-606: an unrecognized per-profile {@code placement:} used to silently fall back to legacy
+     * pane placement — {@link BridgedConfig.Profile#tabPlacement()} only checked equality against
+     * {@code "tab"}.
+     */
+    @Test
+    void unknownProfilePlacementIsRefusedAtLoadNamingTheProfileAndTheAcceptedSet(@TempDir Path dir) throws Exception {
+        Path f = dir.resolve("placement-typo.yaml");
+        Files.writeString(f, """
+                profiles:
+                  gx10:
+                    baseUrl: http://gx10.gw:8000
+                    placement: tabb
+                """);
+
+        IllegalStateException e = assertThrows(IllegalStateException.class, () -> BridgedConfig.load(f));
+        assertTrue(e.getMessage().contains("gx10"), "error names the profile: " + e.getMessage());
+        assertTrue(e.getMessage().contains("tabb"), "error names the bad value: " + e.getMessage());
+        assertTrue(e.getMessage().contains("tab") && e.getMessage().contains("pane"),
+                "error names the accepted set: " + e.getMessage());
+    }
+
+    @Test
+    void absentProfilePlacementDefaultsToTab(@TempDir Path dir) throws Exception {
+        Path f = dir.resolve("placement-absent.yaml");
+        Files.writeString(f, """
+                profiles:
+                  gx10:
+                    baseUrl: http://gx10.gw:8000
+                """);
+
+        BridgedConfig cfg = BridgedConfig.load(f);
+        BridgedConfig.Profile w = cfg.profiles().get("gx10");
+        assertTrue(w.tabPlacement(), "an absent placement must keep defaulting to tab");
+    }
+
+    /**
+     * CB-606: the top-level {@code placement:} policy name WAS validated, but only lazily, by
+     * {@code PlacementPolicies.fromName} through {@code CompositePeerLauncher}'s per-spawn
+     * {@code Supplier} — so a bad name still started a daemon that looked healthy and failed only
+     * the first time something spawned without naming a profile. This must now fail at load.
+     */
+    @Test
+    void unknownTopLevelPlacementPolicyIsRefusedAtLoadNotLazilyAtFirstSpawn(@TempDir Path dir) throws Exception {
+        Path f = dir.resolve("placement-policy-typo.yaml");
+        Files.writeString(f, """
+                bind:
+                  port: 8080
+                placement: weightd
+                """);
+
+        IllegalStateException e = assertThrows(IllegalStateException.class, () -> BridgedConfig.load(f));
+        assertTrue(e.getMessage().contains("weightd"), "error names the bad value: " + e.getMessage());
+        assertTrue(e.getMessage().contains("fixed") && e.getMessage().contains("round-robin")
+                        && e.getMessage().contains("weighted"),
+                "error names the accepted set: " + e.getMessage());
+    }
+
     @Test
     void subscriptionFlagBindsAndDefaultsFalse(@TempDir Path dir) throws Exception {
         Path f = dir.resolve("subscription.yaml");