Authentication with username and password

[marolo2]

Hello Everyone,
I would like to ask for help with authentication to OPC UA server using username and password.
Below snip of my code how I am creating opc client.

username := "user"
password := "password"

opts := []opcua.Option{
opcua.SecurityMode(ua.MessageSecurityModeNone),
opcua.AuthUsername(username, password),
opcua.AutoReconnect(true),
}
ctx := context.Background()
c, _ := opcua.NewClient(opc.tcp://172.17.0.5:4840", opts...)

but I receive error:
Failed to connect to OPC UA server: The user identity token is not valid. StatusBadIdentityTokenInvalid (0x80200000)

When I switch to anonymous mode I can connect and read values, but not at all with password and username. Others clients (written in python or UAExpert) is working fine.

Thank you for help!

[Dipp3r]

Try setting the authType to UserName. This should work if the server is accepting username authentication.
For example,

opts := []opcua.Option{
  opcua.SecurityPolicy("None"),
  opcua.SecurityModeString("None"),
  opcua.AuthUsername(username, password),
  opcua.SecurityFromEndpoint(ep, ua.UserTokenTypeUserName),        //I think by default its set to anonymous 
  opcua.AutoReconnect(true),
}

"ep" is the endpointDescription returned from the SelectEndpoint method

[marolo2]

Hi,
I add opcua.SelectEndpoint(eps, policy, mode) in my app and it is working. Below snip:

endpointUrl := "opc.tcp://172.17.0.5:4840"

var (
	endpoint = flag.String("endpoint", endpointUrl, "OPC UA Endpoint URL")
)

username := "user"
password := "password"

eps, err := opcua.GetEndpoints(context.Background(), *endpoint)
if err != nil {
	log.Fatal(err)
}

policy := ua.SecurityPolicyURINone
mode := ua.MessageSecurityModeNone
ep := opcua.SelectEndpoint(eps, policy, mode)

// Create a new OPC UA client with username and password
opts := []opcua.Option{
	opcua.SecurityFromEndpoint(ep, ua.UserTokenTypeUserName),
	opcua.SessionTimeout(30 * time.Minute),
	opcua.AutoReconnect(true),
	opcua.ReconnectInterval(time.Second * 10),
	opcua.Lifetime(30 * time.Minute),
	opcua.RequestTimeout(3 * time.Second),
	opcua.AuthUsername(username, password),
}
ctx := context.Background()

c, err := opcua.NewClient(*endpoint, opts...)
if err != nil {
	log.Fatalf("Invalid NewClient: %v", err)
}

if err := c.Connect(ctx); err != nil {
	log.Fatalf("Failed to connect to OPC UA server: %v", err)
}
defer c.Close(ctx)