From 16a94d726a6eec2dd0aa355fc1d1265fd8ee7551 Mon Sep 17 00:00:00 2001
From: Jim McDonald <Jim@mcdee.net>
Date: Tue, 29 Nov 2022 14:20:46 +0000
Subject: [PATCH] Withdrawal credentials operations in advance.

Allow withdrawal credentials change operations to be generated prior to
the Capella hard fork, allowing queueing if the beacon node supports it.
---
 CHANGELOG.md                             |  3 ++
 cmd/validator/credentials/set/process.go | 68 ++++++++++++++++++++----
 cmd/validatorcredentialsset.go           |  4 +-
 cmd/version.go                           |  2 +-
 4 files changed, 63 insertions(+), 14 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index f3ecc86..780f5a2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,6 @@
+1.26.1
+  - add ability to generate validator credentials change operations prior to the fork in which they become usable
+
 1.26.0
   - add commands and documentation to set user validator credentials (not usable until capella)
 
diff --git a/cmd/validator/credentials/set/process.go b/cmd/validator/credentials/set/process.go
index 0c2fc89..135924f 100644
--- a/cmd/validator/credentials/set/process.go
+++ b/cmd/validator/credentials/set/process.go
@@ -114,24 +114,70 @@ func (c *command) populateChainInfo(ctx context.Context) error {
 	}
 
 	// Obtain genesis validators root.
-	genesis, err := c.consensusClient.(consensusclient.GenesisProvider).Genesis(ctx)
-	if err != nil {
-		return errors.Wrap(err, "failed to obtain genesis information")
+	if c.genesisValidatorsRoot != "" {
+		// Genesis validators root supplied manually.
+		genesisValidatorsRoot, err := hex.DecodeString(strings.TrimPrefix(c.genesisValidatorsRoot, "0x"))
+		if err != nil {
+			return errors.Wrap(err, "invalid genesis validators root supplied")
+		}
+		if len(genesisValidatorsRoot) != phase0.RootLength {
+			return errors.New("invalid length for genesis validators root")
+		}
+		copy(c.chainInfo.GenesisValidatorsRoot[:], genesisValidatorsRoot)
+	} else {
+		// Genesis validators root obtained from beacon node.
+		genesis, err := c.consensusClient.(consensusclient.GenesisProvider).Genesis(ctx)
+		if err != nil {
+			return errors.Wrap(err, "failed to obtain genesis information")
+		}
+		c.chainInfo.GenesisValidatorsRoot = genesis.GenesisValidatorsRoot
+	}
+	if c.debug {
+		fmt.Printf("Genesis validators root is %#x\n", c.chainInfo.GenesisValidatorsRoot)
 	}
-	c.chainInfo.GenesisValidatorsRoot = genesis.GenesisValidatorsRoot
 
 	// Obtain epoch.
 	c.chainInfo.Epoch = c.chainTime.CurrentEpoch()
 
 	// Obtain fork version.
-	forkSchedule, err := c.consensusClient.(consensusclient.ForkScheduleProvider).ForkSchedule(ctx)
-	if err != nil {
-		return errors.Wrap(err, "failed to obtain fork schedule")
-	}
-	for i := range forkSchedule {
-		if forkSchedule[i].Epoch <= c.chainInfo.Epoch {
-			c.chainInfo.ForkVersion = forkSchedule[i].CurrentVersion
+	if c.forkVersion != "" {
+		// Fork version supplied manually.
+		forkVersion, err := hex.DecodeString(strings.TrimPrefix(c.forkVersion, "0x"))
+		if err != nil {
+			return errors.Wrap(err, "invalid fork version supplied")
 		}
+		if len(forkVersion) != phase0.ForkVersionLength {
+			return errors.New("invalid length for fork version")
+		}
+		copy(c.chainInfo.ForkVersion[:], forkVersion)
+	} else {
+		// Fork version obtained from beacon node.
+		forkSchedule, err := c.consensusClient.(consensusclient.ForkScheduleProvider).ForkSchedule(ctx)
+		if err != nil {
+			return errors.Wrap(err, "failed to obtain fork schedule")
+		}
+		if len(forkSchedule) < 4 {
+			return errors.New("beacon node not providing capella fork schedule; provide manually with --fork-version")
+		}
+		for i := range forkSchedule {
+			// Need to be at least fork 3 (i.e. capella)
+			if i < 3 {
+				continue
+			}
+			if i == 3 {
+				// Force use of capella even if we aren't there yet, to allow credential
+				// change operations to be signed in advance with a signature that will be
+				// valid once capella goes live.
+				c.chainInfo.ForkVersion = forkSchedule[i].CurrentVersion
+				continue
+			}
+			if forkSchedule[i].Epoch <= c.chainInfo.Epoch {
+				c.chainInfo.ForkVersion = forkSchedule[i].CurrentVersion
+			}
+		}
+	}
+	if c.debug {
+		fmt.Printf("Fork version is %#x\n", c.chainInfo.ForkVersion)
 	}
 
 	// Calculate domain.
diff --git a/cmd/validatorcredentialsset.go b/cmd/validatorcredentialsset.go
index 9bdebc5..6febf52 100644
--- a/cmd/validatorcredentialsset.go
+++ b/cmd/validatorcredentialsset.go
@@ -60,8 +60,8 @@ func init() {
 	validatorCredentialsSetCmd.Flags().String("signed-operation", "", "Use pre-defined JSON signed operation as created by --json to transmit the credentials change operation")
 	validatorCredentialsSetCmd.Flags().Bool("json", false, "Generate JSON data containing a signed operation rather than broadcast it to the network (implied when offline)")
 	validatorCredentialsSetCmd.Flags().Bool("offline", false, "Do not attempt to connect to a beacon node to obtain information for the operation")
-	validatorCredentialsSetCmd.Flags().String("fork-version", "", "Fork version to use for signing (offline only)")
-	validatorCredentialsSetCmd.Flags().String("genesis-validators-root", "", "Genesis validators root to use for signing (offline only)")
+	validatorCredentialsSetCmd.Flags().String("fork-version", "", "Fork version to use for signing (overrides fetching from beacon node)")
+	validatorCredentialsSetCmd.Flags().String("genesis-validators-root", "", "Genesis validators root to use for signing (overrides fetching from beacon node)")
 }
 
 func validatorCredentialsSetBindings() {
diff --git a/cmd/version.go b/cmd/version.go
index aab0a29..82f4543 100644
--- a/cmd/version.go
+++ b/cmd/version.go
@@ -24,7 +24,7 @@ import (
 
 // ReleaseVersion is the release version of the codebase.
 // Usually overridden by tag names when building binaries.
-var ReleaseVersion = "local build (latest release 1.26.0)"
+var ReleaseVersion = "local build (latest release 1.26.1)"
 
 // versionCmd represents the version command
 var versionCmd = &cobra.Command{