package opts import ( "fmt" "net" "os" "strings" fopts "github.com/docker/docker/opts" ) // ValidateAttach validates that the specified string is a valid attach option. func ValidateAttach(val string) (string, error) { s := strings.ToLower(val) for _, str := range []string{"stdin", "stdout", "stderr"} { if s == str { return s, nil } } return val, fmt.Errorf("valid streams are STDIN, STDOUT and STDERR") } // ValidateEnv validates an environment variable and returns it. // If no value is specified, it returns the current value using os.Getenv. // // As on ParseEnvFile and related to #16585, environment variable names // are not validate what so ever, it's up to application inside docker // to validate them or not. func ValidateEnv(val string) (string, error) { arr := strings.Split(val, "=") if len(arr) > 1 { return val, nil } if !doesEnvExist(val) { return val, nil } return fmt.Sprintf("%s=%s", val, os.Getenv(val)), nil } func doesEnvExist(name string) bool { for _, entry := range os.Environ() { parts := strings.SplitN(entry, "=", 2) if parts[0] == name { return true } } return false } // ValidateArg validates a build-arg variable and returns it. // Build-arg is in the form of = where is required. func ValidateArg(val string) (string, error) { arr := strings.Split(val, "=") if len(arr) > 1 && isNotEmpty(arr[0]) { return val, nil } return "", fmt.Errorf("bad format for build-arg: %s", val) } func isNotEmpty(val string) bool { return len(val) > 0 } // ValidateExtraHost validates that the specified string is a valid extrahost and returns it. // ExtraHost is in the form of name:ip where the ip has to be a valid ip (IPv4 or IPv6). func ValidateExtraHost(val string) (string, error) { // allow for IPv6 addresses in extra hosts by only splitting on first ":" arr := strings.SplitN(val, ":", 2) if len(arr) != 2 || len(arr[0]) == 0 { return "", fmt.Errorf("bad format for add-host: %q", val) } if _, err := fopts.ValidateIPAddress(arr[1]); err != nil { return "", fmt.Errorf("invalid IP address in add-host: %q", arr[1]) } return val, nil } // ValidateMACAddress validates a MAC address. func ValidateMACAddress(val string) (string, error) { _, err := net.ParseMAC(strings.TrimSpace(val)) if err != nil { return "", err } return val, nil }