package csprofiles import ( "fmt" "time" "github.com/antonmedv/expr" "github.com/antonmedv/expr/vm" "github.com/crowdsecurity/crowdsec/pkg/csconfig" "github.com/crowdsecurity/crowdsec/pkg/exprhelpers" "github.com/crowdsecurity/crowdsec/pkg/models" "github.com/crowdsecurity/crowdsec/pkg/types" "github.com/pkg/errors" log "github.com/sirupsen/logrus" ) type Runtime struct { RuntimeFilters []*vm.Program `json:"-" yaml:"-"` DebugFilters []*exprhelpers.ExprDebugger `json:"-" yaml:"-"` RuntimeDurationExpr *vm.Program `json:"-" yaml:"-"` DebugDurationExpr *exprhelpers.ExprDebugger `json:"-" yaml:"-"` Cfg *csconfig.ProfileCfg `json:"-" yaml:"-"` Logger *log.Entry `json:"-" yaml:"-"` } var defaultDuration = "4h" func NewProfile(profilesCfg []*csconfig.ProfileCfg) ([]*Runtime, error) { var err error profilesRuntime := make([]*Runtime, 0) for _, profile := range profilesCfg { var runtimeFilter, runtimeDurationExpr *vm.Program var debugFilter, debugDurationExpr *exprhelpers.ExprDebugger runtime := &Runtime{} xlog := log.New() if err := types.ConfigureLogger(xlog); err != nil { log.Fatalf("While creating profiles-specific logger : %s", err) } xlog.SetLevel(log.InfoLevel) runtime.Logger = xlog.WithFields(log.Fields{ "type": "profile", "name": profile.Name, }) runtime.RuntimeFilters = make([]*vm.Program, len(profile.Filters)) runtime.DebugFilters = make([]*exprhelpers.ExprDebugger, len(profile.Filters)) runtime.Cfg = profile for fIdx, filter := range profile.Filters { if runtimeFilter, err = expr.Compile(filter, expr.Env(exprhelpers.GetExprEnv(map[string]interface{}{"Alert": &models.Alert{}}))); err != nil { return []*Runtime{}, errors.Wrapf(err, "error compiling filter of '%s'", profile.Name) } runtime.RuntimeFilters[fIdx] = runtimeFilter if profile.Debug != nil && *profile.Debug { if debugFilter, err = exprhelpers.NewDebugger(filter, expr.Env(exprhelpers.GetExprEnv(map[string]interface{}{"Alert": &models.Alert{}}))); err != nil { log.Debugf("Error compiling debug filter of %s : %s", profile.Name, err) // Don't fail if we can't compile the filter - for now // return errors.Wrapf(err, "Error compiling debug filter of %s", profile.Name) } runtime.DebugFilters[fIdx] = debugFilter runtime.Logger.Logger.SetLevel(log.DebugLevel) } } if profile.DurationExpr != "" { if runtimeDurationExpr, err = expr.Compile(profile.DurationExpr, expr.Env(exprhelpers.GetExprEnv(map[string]interface{}{"Alert": &models.Alert{}}))); err != nil { return []*Runtime{}, errors.Wrapf(err, "error compiling duration_expr of %s", profile.Name) } runtime.RuntimeDurationExpr = runtimeDurationExpr if profile.Debug != nil && *profile.Debug { if debugDurationExpr, err = exprhelpers.NewDebugger(profile.DurationExpr, expr.Env(exprhelpers.GetExprEnv(map[string]interface{}{"Alert": &models.Alert{}}))); err != nil { log.Debugf("Error compiling debug duration_expr of %s : %s", profile.Name, err) } runtime.DebugDurationExpr = debugDurationExpr } } for _, decision := range profile.Decisions { if runtime.RuntimeDurationExpr == nil { if _, err := time.ParseDuration(*decision.Duration); err != nil { return []*Runtime{}, errors.Wrapf(err, "error parsing duration '%s' of %s", *decision.Duration, profile.Name) } } } profilesRuntime = append(profilesRuntime, runtime) } return profilesRuntime, nil } func (Profile *Runtime) GenerateDecisionFromProfile(Alert *models.Alert) ([]*models.Decision, error) { var decisions []*models.Decision for _, refDecision := range Profile.Cfg.Decisions { decision := models.Decision{} /*the reference decision from profile is in sumulated mode */ if refDecision.Simulated != nil && *refDecision.Simulated { decision.Simulated = new(bool) *decision.Simulated = true /*the event is already in simulation mode */ } else if Alert.Simulated != nil && *Alert.Simulated { decision.Simulated = new(bool) *decision.Simulated = true } /*If the profile specifies a scope, this will prevail. If not, we're going to get the scope from the source itself*/ decision.Scope = new(string) if refDecision.Scope != nil && *refDecision.Scope != "" { *decision.Scope = *refDecision.Scope } else { *decision.Scope = *Alert.Source.Scope } /*some fields are populated from the reference object : duration, scope, type*/ decision.Duration = new(string) if Profile.Cfg.DurationExpr != "" && Profile.RuntimeDurationExpr != nil { duration, err := expr.Run(Profile.RuntimeDurationExpr, exprhelpers.GetExprEnv(map[string]interface{}{"Alert": Alert})) if err != nil { Profile.Logger.Warningf("Failed to run duration_expr : %v", err) *decision.Duration = *refDecision.Duration } else { durationStr := fmt.Sprint(duration) if _, err := time.ParseDuration(durationStr); err != nil { Profile.Logger.Warningf("Failed to parse expr duration result '%s'", duration) *decision.Duration = *refDecision.Duration } else { *decision.Duration = durationStr } } } else { if refDecision.Duration == nil { *decision.Duration = defaultDuration } *decision.Duration = *refDecision.Duration } decision.Type = new(string) *decision.Type = *refDecision.Type /*for the others, let's populate it from the alert and its source*/ decision.Value = new(string) *decision.Value = *Alert.Source.Value decision.Origin = new(string) *decision.Origin = "crowdsec" if refDecision.Origin != nil { *decision.Origin = fmt.Sprintf("%s/%s", *decision.Origin, *refDecision.Origin) } decision.Scenario = new(string) *decision.Scenario = *Alert.Scenario decisions = append(decisions, &decision) } return decisions, nil } //EvaluateProfile is going to evaluate an Alert against a profile to generate Decisions func (Profile *Runtime) EvaluateProfile(Alert *models.Alert) ([]*models.Decision, bool, error) { var decisions []*models.Decision matched := false for eIdx, expression := range Profile.RuntimeFilters { output, err := expr.Run(expression, exprhelpers.GetExprEnv(map[string]interface{}{"Alert": Alert})) if err != nil { Profile.Logger.Warningf("failed to run whitelist expr : %v", err) return nil, matched, errors.Wrapf(err, "while running expression %s", Profile.Cfg.Filters[eIdx]) } switch out := output.(type) { case bool: if Profile.Cfg.Debug != nil && *Profile.Cfg.Debug { Profile.DebugFilters[eIdx].Run(Profile.Logger, out, exprhelpers.GetExprEnv(map[string]interface{}{"Alert": Alert})) } if out { matched = true /*the expression matched, create the associated decision*/ subdecisions, err := Profile.GenerateDecisionFromProfile(Alert) if err != nil { return nil, matched, errors.Wrapf(err, "while generating decision from profile %s", Profile.Cfg.Name) } decisions = append(decisions, subdecisions...) } else { Profile.Logger.Debugf("Profile %s filter is unsuccessful", Profile.Cfg.Name) if Profile.Cfg.OnFailure == "break" { break } } default: return nil, matched, fmt.Errorf("unexpected type %t (%v) while running '%s'", output, output, Profile.Cfg.Filters[eIdx]) } } return decisions, matched, nil }