Fixes Hashivault configuration with Chains

Initially when kms was misconfigured, then the chains
controller pod was getting panic and ended up getting
crashed

Hence, this patch checks it the vault address is valid
and if it is not valid, then returns the error which
handles the pod from getting panic and crashed

Signed-off-by: Puneet Punamiya [email protected]

pkg/chains/signing/kms/kms.go

@@ -17,8 +17,8 @@ package kms
 import (
 	"context"
 	"crypto"
-
 	"github.com/tektoncd/chains/pkg/config"
+	"net/http"
 
 	"github.com/sigstore/sigstore/pkg/signature"
 	"github.com/sigstore/sigstore/pkg/signature/kms"
@@ -41,6 +41,18 @@ type Signer struct {
 // NewSigner returns a configured Signer
 func NewSigner(ctx context.Context, cfg config.KMSSigner) (*Signer, error) {
 	kmsOpts := []signature.RPCOption{}
+
+	if cfg.Auth.Address != "" {
+		resp, err := http.Get(cfg.Auth.Address)
+		if err != nil {
+			return nil, err
+		}
+
+		if resp.StatusCode != 200 {
+			return nil, err
+		}
+	}
+
 	// pass through configuration options to RPCAuth used by KMS in sigstore
 	rpcAuth := options.RPCAuth{
 		Address: cfg.Auth.Address,