feat(config): surface trust anchors; warn on a sub-activation --genesis (#107)

cmd/ion-node/main.go

@@ -175,7 +175,18 @@ func buildConfig(cCtx *cli.Context) (*config.Config, error) {
 		}
 		opts = append(opts, config.WithCheckpoint(height, hash))
 	}
-	return config.New(cCtx.String("network"), opts...)
+	cfg, err := config.New(cCtx.String("network"), opts...)
+	if err != nil {
+		return nil, err
+	}
+	// Sanity: warn (don't fail) if --genesis was overridden far below the network's
+	// ION-activation height — e.g. `--network mainnet --genesis 0` would scan ~667k
+	// pointless pre-ION blocks. A higher-than-default genesis is fine (skips old DIDs).
+	if def, derr := config.ProfileGenesisHeight(cfg.Network); derr == nil && cfg.GenesisHeight < def {
+		log.New(cCtx.Int("v")).Warn("genesis height is below the network's ION activation; scanning starts far too low and wastes time/bandwidth",
+			"network", cfg.Network, "genesisHeight", cfg.GenesisHeight, "expectedActivation", def)
+	}
+	return cfg, nil
 }
 
 // buildHeaderChain installs the trust anchors: the network's shipped checkpoints
@@ -435,10 +446,23 @@ func runConfig(cCtx *cli.Context) error {
 	if err != nil {
 		return err
 	}
+	// Surface the eclipse/fake-chain trust anchors so an operator can confirm them
+	// before launch: the min-chain-work floor (markSynced won't declare synced below
+	// it) and any augmenting checkpoint. The network's shipped checkpoints are always
+	// enforced in addition to these.
+	minChainWork := cfg.MinChainWork
+	if minChainWork == "" {
+		minChainWork = "unset"
+	}
+	checkpoint := "none"
+	if cfg.Checkpoint != nil {
+		checkpoint = fmt.Sprintf("%d:%s", cfg.Checkpoint.Height, cfg.Checkpoint.Hash)
+	}
 	log.New(cCtx.Int("v")).Info("resolved configuration",
 		"network", cfg.Network, "chainParams", cfg.Params.Name, "prefix", cfg.Prefix,
 		"genesisHeight", cfg.GenesisHeight, "confirmationDepth", cfg.ConfirmationDepth,
-		"maxReorgDepth", cfg.MaxReorgDepth, "targetOutbound", cfg.TargetOutbound, "dataDir", cfg.DataDir)
+		"maxReorgDepth", cfg.MaxReorgDepth, "targetOutbound", cfg.TargetOutbound,
+		"minChainWork", minChainWork, "extraCheckpoint", checkpoint, "dataDir", cfg.DataDir)
 	return nil
 }
 

docs/hardening-backlog.md

@@ -52,7 +52,7 @@ All items below survived an independent skeptic re-reading the cited code.
 | 22 | ⚪ low | trivial | security | `keystore-open-no-perm-check` | ✅ done (#97) |
 | 23 | ⚪ low | trivial | operational | `buildpsbt-missing-mainnet-gate` | open |
 | 24 | ⚪ low | small | correctness | `scan-cid-shape-only-no-multihash-validation` | open |
-| 25 | ⚪ low | trivial | operational | `config-command-hides-trust-anchors` | open |
+| 25 | ⚪ low | trivial | operational | `config-command-hides-trust-anchors` | ✅ done (#107) |
 | 26 | ⚪ low | trivial | correctness | `scan-zero-and-overcount-consume-block-cap-slot` | open |
 | 27 | ⚪ low | medium | reliability | `observer-shutdown-blocks-on-cas-fetch` | open |
 | 28 | ⚪ low | small | resource | `retrypending-loads-full-set-each-pass` | open |
@@ -65,7 +65,7 @@ All items below survived an independent skeptic re-reading the cited code.
 | 35 | ⚪ low | small | test-gap | `walletstore-no-differential-fuzz` | open |
 | 36 | ⚪ low | small | correctness | `headers-no-future-time-and-false-ban` | open |
 | 37 | ⚪ low | small | test-gap | `cmd-ion-node-zero-tests` | open |
-| 38 | ⚪ low | trivial | operational | `genesis-override-no-network-sanity-check` | open |
+| 38 | ⚪ low | trivial | operational | `genesis-override-no-network-sanity-check` | ✅ done (#107) |
 | 39 | ⚪ low | small | test-gap | `p2p-block-fetch-adversarial-untested` | open |
 | 40 | ⚪ low | small | test-gap | `cas-cache-content-integrity-untested` | open |
 

internal/config/profiles.go

@@ -64,6 +64,17 @@ func profileFor(network string) (*Config, error) {
 	}
 }
 
+// ProfileGenesisHeight returns a network's default (ION-activation) scan-start
+// height, before any --genesis override. Used to warn when an override drops the
+// start far below activation (a wasteful misconfiguration).
+func ProfileGenesisHeight(network string) (int32, error) {
+	c, err := profileFor(network)
+	if err != nil {
+		return 0, err
+	}
+	return c.GenesisHeight, nil
+}
+
 // Networks returns the supported network profile names, sorted.
 func Networks() []string {
 	n := []string{"mainnet", "testnet", "signet", "regtest", "simnet"}

internal/config/profiles_test.go

@@ -0,0 +1,26 @@
+package config
+
+import "testing"
+
+func TestProfileGenesisHeight(t *testing.T) {
+	cases := map[string]int32{
+		"mainnet": 667000,
+		"testnet": 1764000,
+		"signet":  0,
+		"regtest": 0,
+		"simnet":  0,
+	}
+	for net, want := range cases {
+		got, err := ProfileGenesisHeight(net)
+		if err != nil {
+			t.Errorf("ProfileGenesisHeight(%q): %v", net, err)
+			continue
+		}
+		if got != want {
+			t.Errorf("ProfileGenesisHeight(%q) = %d, want %d", net, got, want)
+		}
+	}
+	if _, err := ProfileGenesisHeight("nope"); err == nil {
+		t.Error("ProfileGenesisHeight(unknown) should error")
+	}
+}