agent-config: generate and use attestation-agent toml

Generate the attestation-agent toml file aa.toml when aaKBCParams provided
Use the cfg file to start attestation agent service when it exists
Start attestation agent service directly when no cfg file exists

Signed-off-by: Qi Feng Huo <huoqif@cn.ibm.com>

src/cloud-api-adaptor/pkg/adaptor/cloud/cloud.go

@@ -281,7 +281,7 @@ func (s *cloudService) CreateVM(ctx context.Context, req *pb.CreateVMRequest) (r
 			Content: toml,
 		})
 
-		toml, err = agent.CreateConfigFile(s.aaKBCParams, "")
+		toml, err = agent.CreateConfigFile(s.aaKBCParams)
 		if err != nil {
 			return nil, fmt.Errorf("creating attestation agent config: %w", err)
 		}

src/cloud-api-adaptor/pkg/agent/config.go

@@ -18,7 +18,6 @@ type TokenConfigs struct {
 	} `toml:"token_configs.coco_as"`
 	Kbs struct {
 		URL  string `toml:"url"`
-		Cert string `toml:"cert"`
 	} `toml:"token_configs.kbs"`
 }
 
@@ -31,7 +30,7 @@ func parseAAKBCParams(aaKBCParams string) (string, error) {
 	return url, nil
 }
 
-func CreateConfigFile(aaKBCParams string, certStr string) (string, error) {
+func CreateConfigFile(aaKBCParams string) (string, error) {
 	url, err := parseAAKBCParams(aaKBCParams)
 	if err != nil {
 		return "", err
@@ -40,7 +39,6 @@ func CreateConfigFile(aaKBCParams string, certStr string) (string, error) {
 	config := TokenConfigs{}
 	config.CocoAs.URL = ""
 	config.Kbs.URL = url
-	config.Kbs.Cert = certStr
 
 	bytes, err := toml.Marshal(config)
 	if err != nil {

src/cloud-api-adaptor/pkg/agent/config_test.go

@@ -24,10 +24,9 @@ url = ''
 
 [token_configs.kbs]
 url = 'http://127.0.0.1:8080'
-cert = ''
 `
 
-	config, err := CreateConfigFile("cc_kbc::http://127.0.0.1:8080", "")
+	config, err := CreateConfigFile("cc_kbc::http://127.0.0.1:8080")
 	if err != nil {
 		t.Error(err)
 	}