From fa3c7d4bc372a44141457e515cf8b04e36c683a9 Mon Sep 17 00:00:00 2001
From: Marcin Rataj <lidel@lidel.org>
Date: Tue, 6 Aug 2024 00:29:59 +0200
Subject: [PATCH] feat: libp2p.EnableAutoNATv2

Part of https://github.com/ipfs/kubo/issues/10091
We include a flag that allows shutting down V2 in case there are issues
with it.
---
 config/autonat.go       |  7 +++++++
 core/node/groups.go     |  4 +++-
 core/node/libp2p/nat.go |  9 ++++++++-
 docs/config.md          | 19 ++++++++++++++-----
 4 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/config/autonat.go b/config/autonat.go
index eb87b48e6f4..e8940d14eeb 100644
--- a/config/autonat.go
+++ b/config/autonat.go
@@ -20,6 +20,9 @@ const (
 	// AutoNATServiceDisabled indicates that the user has disabled the
 	// AutoNATService.
 	AutoNATServiceDisabled
+	// AutoNATServiceEnabledV1Only forces use of V1 and disables V2
+	// (used for testing)
+	AutoNATServiceEnabledV1Only
 )
 
 func (m *AutoNATServiceMode) UnmarshalText(text []byte) error {
@@ -30,6 +33,8 @@ func (m *AutoNATServiceMode) UnmarshalText(text []byte) error {
 		*m = AutoNATServiceEnabled
 	case "disabled":
 		*m = AutoNATServiceDisabled
+	case "legacy-v1":
+		*m = AutoNATServiceEnabledV1Only
 	default:
 		return fmt.Errorf("unknown autonat mode: %s", string(text))
 	}
@@ -44,6 +49,8 @@ func (m AutoNATServiceMode) MarshalText() ([]byte, error) {
 		return []byte("enabled"), nil
 	case AutoNATServiceDisabled:
 		return []byte("disabled"), nil
+	case AutoNATServiceEnabledV1Only:
+		return []byte("legacy-v1"), nil
 	default:
 		return nil, fmt.Errorf("unknown autonat mode: %d", m)
 	}
diff --git a/core/node/groups.go b/core/node/groups.go
index 3df945fd2cc..a12cc7b7f1d 100644
--- a/core/node/groups.go
+++ b/core/node/groups.go
@@ -105,7 +105,9 @@ func LibP2P(bcfg *BuildCfg, cfg *config.Config, userResourceOverrides rcmgr.Part
 		// to dhtclient.
 		fallthrough
 	case config.AutoNATServiceEnabled:
-		autonat = fx.Provide(libp2p.AutoNATService(cfg.AutoNAT.Throttle))
+		autonat = fx.Provide(libp2p.AutoNATService(cfg.AutoNAT.Throttle, false))
+	case config.AutoNATServiceEnabledV1Only:
+		autonat = fx.Provide(libp2p.AutoNATService(cfg.AutoNAT.Throttle, true))
 	}
 
 	enableRelayTransport := cfg.Swarm.Transports.Network.Relay.WithDefault(true) // nolint
diff --git a/core/node/libp2p/nat.go b/core/node/libp2p/nat.go
index fc72d7fb3c0..6d3cd09c38e 100644
--- a/core/node/libp2p/nat.go
+++ b/core/node/libp2p/nat.go
@@ -9,7 +9,7 @@ import (
 
 var NatPortMap = simpleOpt(libp2p.NATPortMap())
 
-func AutoNATService(throttle *config.AutoNATThrottleConfig) func() Libp2pOpts {
+func AutoNATService(throttle *config.AutoNATThrottleConfig, v1only bool) func() Libp2pOpts {
 	return func() (opts Libp2pOpts) {
 		opts.Opts = append(opts.Opts, libp2p.EnableNATService())
 		if throttle != nil {
@@ -21,6 +21,13 @@ func AutoNATService(throttle *config.AutoNATThrottleConfig) func() Libp2pOpts {
 				),
 			)
 		}
+
+		// While V1 still exists and V2 rollout is in progress
+		// (https://github.com/ipfs/kubo/issues/10091) we check a flag that
+		// allows users to disable V2 and run V1-only mode
+		if !v1only {
+			opts.Opts = append(opts.Opts, libp2p.EnableAutoNATv2())
+		}
 		return opts
 	}
 }
diff --git a/docs/config.md b/docs/config.md
index 8a09b7fe066..b37543e9cc8 100644
--- a/docs/config.md
+++ b/docs/config.md
@@ -552,7 +552,7 @@ Type: `array[string]`
 
 ## `AutoNAT`
 
-Contains the configuration options for the AutoNAT service. The AutoNAT service
+Contains the configuration options for the [AutoNAT]() service. The AutoNAT service
 helps other nodes on the network determine if they're publicly reachable from
 the rest of the internet.
 
@@ -561,13 +561,22 @@ the rest of the internet.
 When unset (default), the AutoNAT service defaults to _enabled_. Otherwise, this
 field can take one of two values:
 
-* "enabled" - Enable the service (unless the node determines that it, itself,
-  isn't reachable by the public internet).
-* "disabled" - Disable the service.
+* `enabled` - Enable the V1+V2 service (unless the node determines that it,
+  itself, isn't reachable by the public internet).
+* `legacy-v1` - Same as `enabled` but only V1 service is enabled. Used for testing
+  during as few releases as we [transition to V2](https://github.com/ipfs/kubo/issues/10091), will be removed in the future.
+* `disabled` - Disable the service.
 
 Additional modes may be added in the future.
 
-Type: `string` (one of `"enabled"` or `"disabled"`)
+> [!IMPORTANT]
+> We are in the progress of [rolling out AutoNAT V2](https://github.com/ipfs/kubo/issues/10091).
+> Right now, by default, a publicly diallable Kubo provides both V1 and V2 service to other peers,
+> but only V1 is used by Kubo as a client. In a future release we will remove V1 and switch client to use V2.
+
+Default: `enabled`
+
+Type: `optionalString`
 
 ### `AutoNAT.Throttle`