crowdsec/pkg/leakybucket/manager_load.go
2024-07-22 12:14:46 +02:00

512 lines
19 KiB
Go

package leakybucket
import (
"encoding/json"
"errors"
"fmt"
"io"
"os"
"path/filepath"
"strings"
"sync"
"time"
"github.com/davecgh/go-spew/spew"
"github.com/expr-lang/expr"
"github.com/expr-lang/expr/vm"
"github.com/goombaio/namegenerator"
log "github.com/sirupsen/logrus"
"gopkg.in/tomb.v2"
yaml "gopkg.in/yaml.v2"
"github.com/crowdsecurity/crowdsec/pkg/alertcontext"
"github.com/crowdsecurity/crowdsec/pkg/csconfig"
"github.com/crowdsecurity/crowdsec/pkg/cwhub"
"github.com/crowdsecurity/crowdsec/pkg/cwversion"
"github.com/crowdsecurity/crowdsec/pkg/exprhelpers"
"github.com/crowdsecurity/crowdsec/pkg/types"
)
// BucketFactory struct holds all fields for any bucket configuration. This is to have a
// generic struct for buckets. This can be seen as a bucket factory.
type BucketFactory struct {
FormatVersion string `yaml:"format"`
Author string `yaml:"author"`
Description string `yaml:"description"`
References []string `yaml:"references"`
Type string `yaml:"type"` // Type can be : leaky, counter, trigger. It determines the main bucket characteristics
Name string `yaml:"name"` // Name of the bucket, used later in log and user-messages. Should be unique
Capacity int `yaml:"capacity"` // Capacity is applicable to leaky buckets and determines the "burst" capacity
LeakSpeed string `yaml:"leakspeed"` // Leakspeed is a float representing how many events per second leak out of the bucket
Duration string `yaml:"duration"` // Duration allows 'counter' buckets to have a fixed life-time
Filter string `yaml:"filter"` // Filter is an expr that determines if an event is elligible for said bucket. Filter is evaluated against the Event struct
GroupBy string `yaml:"groupby,omitempty"` // groupy is an expr that allows to determine the partitions of the bucket. A common example is the source_ip
Distinct string `yaml:"distinct"` // Distinct, when present, adds a `Pour()` processor that will only pour uniq items (based on distinct expr result)
Debug bool `yaml:"debug"` // Debug, when set to true, will enable debugging for _this_ scenario specifically
Labels map[string]interface{} `yaml:"labels"` // Labels is K:V list aiming at providing context the overflow
Blackhole string `yaml:"blackhole,omitempty"` // Blackhole is a duration that, if present, will prevent same bucket partition to overflow more often than $duration
logger *log.Entry `yaml:"-"` // logger is bucket-specific logger (used by Debug as well)
Reprocess bool `yaml:"reprocess"` // Reprocess, if true, will for the bucket to be re-injected into processing chain
CacheSize int `yaml:"cache_size"` // CacheSize, if > 0, limits the size of in-memory cache of the bucket
Profiling bool `yaml:"profiling"` // Profiling, if true, will make the bucket record pours/overflows/etc.
OverflowFilter string `yaml:"overflow_filter"` // OverflowFilter if present, is a filter that must return true for the overflow to go through
ConditionalOverflow string `yaml:"condition"` // condition if present, is an expression that must return true for the bucket to overflow
BayesianPrior float32 `yaml:"bayesian_prior"`
BayesianThreshold float32 `yaml:"bayesian_threshold"`
BayesianConditions []RawBayesianCondition `yaml:"bayesian_conditions"` // conditions for the bayesian bucket
ScopeType types.ScopeType `yaml:"scope,omitempty"` // to enforce a different remediation than blocking an IP. Will default this to IP
BucketName string `yaml:"-"`
Filename string `yaml:"-"`
RunTimeFilter *vm.Program `json:"-"`
RunTimeGroupBy *vm.Program `json:"-"`
Data []*types.DataSource `yaml:"data,omitempty"`
DataDir string `yaml:"-"`
CancelOnFilter string `yaml:"cancel_on,omitempty"` // a filter that, if matched, kills the bucket
leakspeed time.Duration // internal representation of `Leakspeed`
duration time.Duration // internal representation of `Duration`
ret chan types.Event // the bucket-specific output chan for overflows
processors []Processor // processors is the list of hooks for pour/overflow/create (cf. uniq, blackhole etc.)
output bool // ??
ScenarioVersion string `yaml:"version,omitempty"`
hash string `yaml:"-"`
Simulated bool `yaml:"simulated"` // Set to true if the scenario instantiating the bucket was in the exclusion list
tomb *tomb.Tomb `yaml:"-"`
wgPour *sync.WaitGroup `yaml:"-"`
wgDumpState *sync.WaitGroup `yaml:"-"`
orderEvent bool
}
// we use one NameGenerator for all the future buckets
var seed namegenerator.Generator = namegenerator.NewNameGenerator(time.Now().UTC().UnixNano())
func ValidateFactory(bucketFactory *BucketFactory) error {
if bucketFactory.Name == "" {
return errors.New("bucket must have name")
}
if bucketFactory.Description == "" {
return errors.New("description is mandatory")
}
if bucketFactory.Type == "leaky" {
if bucketFactory.Capacity <= 0 { // capacity must be a positive int
return fmt.Errorf("bad capacity for leaky '%d'", bucketFactory.Capacity)
}
if bucketFactory.LeakSpeed == "" {
return errors.New("leakspeed can't be empty for leaky")
}
if bucketFactory.leakspeed == 0 {
return fmt.Errorf("bad leakspeed for leaky '%s'", bucketFactory.LeakSpeed)
}
} else if bucketFactory.Type == "counter" {
if bucketFactory.Duration == "" {
return errors.New("duration can't be empty for counter")
}
if bucketFactory.duration == 0 {
return fmt.Errorf("bad duration for counter bucket '%d'", bucketFactory.duration)
}
if bucketFactory.Capacity != -1 {
return errors.New("counter bucket must have -1 capacity")
}
} else if bucketFactory.Type == "trigger" {
if bucketFactory.Capacity != 0 {
return errors.New("trigger bucket must have 0 capacity")
}
} else if bucketFactory.Type == "conditional" {
if bucketFactory.ConditionalOverflow == "" {
return errors.New("conditional bucket must have a condition")
}
if bucketFactory.Capacity != -1 {
bucketFactory.logger.Warnf("Using a value different than -1 as capacity for conditional bucket, this may lead to unexpected overflows")
}
if bucketFactory.LeakSpeed == "" {
return errors.New("leakspeed can't be empty for conditional bucket")
}
if bucketFactory.leakspeed == 0 {
return fmt.Errorf("bad leakspeed for conditional bucket '%s'", bucketFactory.LeakSpeed)
}
} else if bucketFactory.Type == "bayesian" {
if bucketFactory.BayesianConditions == nil {
return errors.New("bayesian bucket must have bayesian conditions")
}
if bucketFactory.BayesianPrior == 0 {
return errors.New("bayesian bucket must have a valid, non-zero prior")
}
if bucketFactory.BayesianThreshold == 0 {
return errors.New("bayesian bucket must have a valid, non-zero threshold")
}
if bucketFactory.BayesianPrior > 1 {
return errors.New("bayesian bucket must have a valid, non-zero prior")
}
if bucketFactory.BayesianThreshold > 1 {
return errors.New("bayesian bucket must have a valid, non-zero threshold")
}
if bucketFactory.Capacity != -1 {
return errors.New("bayesian bucket must have capacity -1")
}
} else {
return fmt.Errorf("unknown bucket type '%s'", bucketFactory.Type)
}
switch bucketFactory.ScopeType.Scope {
case types.Undefined:
bucketFactory.ScopeType.Scope = types.Ip
case types.Ip:
case types.Range:
var (
runTimeFilter *vm.Program
err error
)
if bucketFactory.ScopeType.Filter != "" {
if runTimeFilter, err = expr.Compile(bucketFactory.ScopeType.Filter, exprhelpers.GetExprOptions(map[string]interface{}{"evt": &types.Event{}})...); err != nil {
return fmt.Errorf("error compiling the scope filter: %w", err)
}
bucketFactory.ScopeType.RunTimeFilter = runTimeFilter
}
default:
// Compile the scope filter
var (
runTimeFilter *vm.Program
err error
)
if bucketFactory.ScopeType.Filter != "" {
if runTimeFilter, err = expr.Compile(bucketFactory.ScopeType.Filter, exprhelpers.GetExprOptions(map[string]interface{}{"evt": &types.Event{}})...); err != nil {
return fmt.Errorf("error compiling the scope filter: %w", err)
}
bucketFactory.ScopeType.RunTimeFilter = runTimeFilter
}
}
return nil
}
func LoadBuckets(cscfg *csconfig.CrowdsecServiceCfg, hub *cwhub.Hub, files []string, tomb *tomb.Tomb, buckets *Buckets, orderEvent bool) ([]BucketFactory, chan types.Event, error) {
var (
ret = []BucketFactory{}
response chan types.Event
)
response = make(chan types.Event, 1)
for _, f := range files {
log.Debugf("Loading '%s'", f)
if !strings.HasSuffix(f, ".yaml") && !strings.HasSuffix(f, ".yml") {
log.Debugf("Skipping %s : not a yaml file", f)
continue
}
// process the yaml
bucketConfigurationFile, err := os.Open(f)
if err != nil {
log.Errorf("Can't access leaky configuration file %s", f)
return nil, nil, err
}
defer bucketConfigurationFile.Close()
dec := yaml.NewDecoder(bucketConfigurationFile)
dec.SetStrict(true)
for {
bucketFactory := BucketFactory{}
err = dec.Decode(&bucketFactory)
if err != nil {
if !errors.Is(err, io.EOF) {
log.Errorf("Bad yaml in %s : %v", f, err)
return nil, nil, fmt.Errorf("bad yaml in %s : %v", f, err)
}
log.Tracef("End of yaml file")
break
}
bucketFactory.DataDir = hub.GetDataDir()
// check empty
if bucketFactory.Name == "" {
log.Errorf("Won't load nameless bucket")
return nil, nil, errors.New("nameless bucket")
}
// check compat
if bucketFactory.FormatVersion == "" {
log.Tracef("no version in %s : %s, assuming '1.0'", bucketFactory.Name, f)
bucketFactory.FormatVersion = "1.0"
}
ok, err := cwversion.Satisfies(bucketFactory.FormatVersion, cwversion.Constraint_scenario)
if err != nil {
return nil, nil, fmt.Errorf("failed to check version: %w", err)
}
if !ok {
log.Errorf("can't load %s : %s doesn't satisfy scenario format %s, skip", bucketFactory.Name, bucketFactory.FormatVersion, cwversion.Constraint_scenario)
continue
}
bucketFactory.Filename = filepath.Clean(f)
bucketFactory.BucketName = seed.Generate()
bucketFactory.ret = response
hubItem := hub.GetItemByPath(bucketFactory.Filename)
if hubItem == nil {
log.Errorf("scenario %s (%s) could not be found in hub (ignore if in unit tests)", bucketFactory.Name, bucketFactory.Filename)
} else {
if cscfg.SimulationConfig != nil {
bucketFactory.Simulated = cscfg.SimulationConfig.IsSimulated(hubItem.Name)
}
bucketFactory.ScenarioVersion = hubItem.State.LocalVersion
bucketFactory.hash = hubItem.State.LocalHash
}
bucketFactory.wgDumpState = buckets.wgDumpState
bucketFactory.wgPour = buckets.wgPour
err = LoadBucket(&bucketFactory, tomb)
if err != nil {
log.Errorf("Failed to load bucket %s : %v", bucketFactory.Name, err)
return nil, nil, fmt.Errorf("loading of %s failed : %v", bucketFactory.Name, err)
}
bucketFactory.orderEvent = orderEvent
ret = append(ret, bucketFactory)
}
}
if err := alertcontext.NewAlertContext(cscfg.ContextToSend, cscfg.ConsoleContextValueLength); err != nil {
return nil, nil, fmt.Errorf("unable to load alert context: %w", err)
}
log.Infof("Loaded %d scenarios", len(ret))
return ret, response, nil
}
/* Init recursively process yaml files from a directory and loads them as BucketFactory */
func LoadBucket(bucketFactory *BucketFactory, tomb *tomb.Tomb) error {
var err error
if bucketFactory.Debug {
clog := log.New()
if err := types.ConfigureLogger(clog); err != nil {
return fmt.Errorf("while creating bucket-specific logger: %w", err)
}
clog.SetLevel(log.DebugLevel)
bucketFactory.logger = clog.WithFields(log.Fields{
"cfg": bucketFactory.BucketName,
"name": bucketFactory.Name,
})
} else {
/* else bind it to the default one (might find something more elegant here)*/
bucketFactory.logger = log.WithFields(log.Fields{
"cfg": bucketFactory.BucketName,
"name": bucketFactory.Name,
})
}
if bucketFactory.LeakSpeed != "" {
if bucketFactory.leakspeed, err = time.ParseDuration(bucketFactory.LeakSpeed); err != nil {
return fmt.Errorf("bad leakspeed '%s' in %s : %v", bucketFactory.LeakSpeed, bucketFactory.Filename, err)
}
} else {
bucketFactory.leakspeed = time.Duration(0)
}
if bucketFactory.Duration != "" {
if bucketFactory.duration, err = time.ParseDuration(bucketFactory.Duration); err != nil {
return fmt.Errorf("invalid Duration '%s' in %s : %v", bucketFactory.Duration, bucketFactory.Filename, err)
}
}
if bucketFactory.Filter == "" {
bucketFactory.logger.Warning("Bucket without filter, abort.")
return errors.New("bucket without filter directive")
}
bucketFactory.RunTimeFilter, err = expr.Compile(bucketFactory.Filter, exprhelpers.GetExprOptions(map[string]interface{}{"evt": &types.Event{}})...)
if err != nil {
return fmt.Errorf("invalid filter '%s' in %s : %v", bucketFactory.Filter, bucketFactory.Filename, err)
}
if bucketFactory.GroupBy != "" {
bucketFactory.RunTimeGroupBy, err = expr.Compile(bucketFactory.GroupBy, exprhelpers.GetExprOptions(map[string]interface{}{"evt": &types.Event{}})...)
if err != nil {
return fmt.Errorf("invalid groupby '%s' in %s : %v", bucketFactory.GroupBy, bucketFactory.Filename, err)
}
}
bucketFactory.logger.Infof("Adding %s bucket", bucketFactory.Type)
// return the Holder corresponding to the type of bucket
bucketFactory.processors = []Processor{}
switch bucketFactory.Type {
case "leaky":
bucketFactory.processors = append(bucketFactory.processors, &DumbProcessor{})
case "trigger":
bucketFactory.processors = append(bucketFactory.processors, &Trigger{})
case "counter":
bucketFactory.processors = append(bucketFactory.processors, &DumbProcessor{})
case "conditional":
bucketFactory.processors = append(bucketFactory.processors, &DumbProcessor{})
case "bayesian":
bucketFactory.processors = append(bucketFactory.processors, &DumbProcessor{})
default:
return fmt.Errorf("invalid type '%s' in %s : %v", bucketFactory.Type, bucketFactory.Filename, err)
}
if bucketFactory.Distinct != "" {
bucketFactory.logger.Tracef("Adding a non duplicate filter")
bucketFactory.processors = append(bucketFactory.processors, &Uniq{})
}
if bucketFactory.CancelOnFilter != "" {
bucketFactory.logger.Tracef("Adding a cancel_on filter")
bucketFactory.processors = append(bucketFactory.processors, &CancelOnFilter{})
}
if bucketFactory.OverflowFilter != "" {
bucketFactory.logger.Tracef("Adding an overflow filter")
filovflw, err := NewOverflowFilter(bucketFactory)
if err != nil {
bucketFactory.logger.Errorf("Error creating overflow_filter : %s", err)
return fmt.Errorf("error creating overflow_filter: %w", err)
}
bucketFactory.processors = append(bucketFactory.processors, filovflw)
}
if bucketFactory.Blackhole != "" {
bucketFactory.logger.Tracef("Adding blackhole.")
blackhole, err := NewBlackhole(bucketFactory)
if err != nil {
bucketFactory.logger.Errorf("Error creating blackhole : %s", err)
return fmt.Errorf("error creating blackhole : %w", err)
}
bucketFactory.processors = append(bucketFactory.processors, blackhole)
}
if bucketFactory.ConditionalOverflow != "" {
bucketFactory.logger.Tracef("Adding conditional overflow")
bucketFactory.processors = append(bucketFactory.processors, &ConditionalOverflow{})
}
if bucketFactory.BayesianThreshold != 0 {
bucketFactory.logger.Tracef("Adding bayesian processor")
bucketFactory.processors = append(bucketFactory.processors, &BayesianBucket{})
}
for _, data := range bucketFactory.Data {
if data.DestPath == "" {
bucketFactory.logger.Errorf("no dest_file provided for '%s'", bucketFactory.Name)
continue
}
err = exprhelpers.FileInit(bucketFactory.DataDir, data.DestPath, data.Type)
if err != nil {
bucketFactory.logger.Errorf("unable to init data for file '%s': %s", data.DestPath, err)
}
if data.Type == "regexp" { // cache only makes sense for regexp
exprhelpers.RegexpCacheInit(data.DestPath, *data)
}
}
bucketFactory.output = false
if err := ValidateFactory(bucketFactory); err != nil {
return fmt.Errorf("invalid bucket from %s : %v", bucketFactory.Filename, err)
}
bucketFactory.tomb = tomb
return nil
}
func LoadBucketsState(file string, buckets *Buckets, bucketFactories []BucketFactory) error {
var state map[string]Leaky
body, err := os.ReadFile(file)
if err != nil {
return fmt.Errorf("can't read state file %s: %w", file, err)
}
if err := json.Unmarshal(body, &state); err != nil {
return fmt.Errorf("can't unmarshal state file %s: %w", file, err)
}
for k, v := range state {
var tbucket *Leaky
log.Debugf("Reloading bucket %s", k)
val, ok := buckets.Bucket_map.Load(k)
if ok {
return fmt.Errorf("key %s already exists: %+v", k, val)
}
// find back our holder
found := false
for _, h := range bucketFactories {
if h.Name == v.Name {
log.Debugf("found factory %s/%s -> %s", h.Author, h.Name, h.Description)
// check in which mode the bucket was
if v.Mode == types.TIMEMACHINE {
tbucket = NewTimeMachine(h)
} else if v.Mode == types.LIVE {
tbucket = NewLeaky(h)
} else {
log.Errorf("Unknown bucket type : %d", v.Mode)
}
/*Trying to restore queue state*/
tbucket.Queue = v.Queue
/*Trying to set the limiter to the saved values*/
tbucket.Limiter.Load(v.SerializedState)
tbucket.In = make(chan *types.Event)
tbucket.Mapkey = k
tbucket.Signal = make(chan bool, 1)
tbucket.First_ts = v.First_ts
tbucket.Last_ts = v.Last_ts
tbucket.Ovflw_ts = v.Ovflw_ts
tbucket.Total_count = v.Total_count
buckets.Bucket_map.Store(k, tbucket)
h.tomb.Go(func() error {
return LeakRoutine(tbucket)
})
<-tbucket.Signal
found = true
break
}
}
if !found {
return fmt.Errorf("unable to find holder for bucket %s: %s", k, spew.Sdump(v))
}
}
log.Infof("Restored %d buckets from dump", len(state))
return nil
}