crowdsec/pkg/parser/stage.go
Thibault bui Koechlin 2016167654 initial import
2020-05-15 11:39:16 +02:00

143 lines
3.7 KiB
Go

package parser
/*
This file contains
- the runtime definition of parser
- the compilation/parsing routines of parser configuration
*/
import (
//"fmt"
"fmt"
"io"
_ "net/http/pprof"
"os"
"path/filepath"
"sort"
"strings"
"time"
"github.com/crowdsecurity/crowdsec/pkg/cwversion"
log "github.com/sirupsen/logrus"
"github.com/goombaio/namegenerator"
yaml "gopkg.in/yaml.v2"
)
var seed namegenerator.Generator = namegenerator.NewNameGenerator(time.Now().UTC().UnixNano())
/*
identify generic component to alter maps, smartfilters ? (static, conditional static etc.)
*/
type Stagefile struct {
Filename string `yaml:"filename"`
Stage string `yaml:"stage"`
}
func LoadStages(stageFiles []Stagefile, pctx *UnixParserCtx) ([]Node, error) {
var nodes []Node
tmpstages := make(map[string]bool)
for _, stageFile := range stageFiles {
if !strings.HasSuffix(stageFile.Filename, ".yaml") {
log.Warningf("skip non yaml : %s", stageFile.Filename)
continue
}
st, err := os.Stat(stageFile.Filename)
if err != nil {
return nil, fmt.Errorf("Failed to stat %s : %v", stageFile, err)
}
if st.IsDir() {
continue
}
yamlFile, err := os.Open(stageFile.Filename)
if err != nil {
return nil, fmt.Errorf("Can't access parsing configuration file %s : %s", stageFile.Filename, err)
}
//process the yaml
dec := yaml.NewDecoder(yamlFile)
dec.SetStrict(true)
nodesCount := 0
for {
node := Node{}
node.OnSuccess = "continue" //default behaviour is to continue
err = dec.Decode(&node)
if err != nil {
if err == io.EOF {
log.Tracef("End of yaml file")
break
}
log.Fatalf("Error decoding parsing configuration file '%s': %v", stageFile.Filename, err)
}
//check for empty bucket
if node.Name == "" && node.Description == "" && node.Author == "" {
log.Infof("Node has no name,author or description. Skipping.")
continue
}
//check compat
if node.FormatVersion == "" {
log.Debugf("no version in %s, assuming '1.0'", stageFile.Filename)
node.FormatVersion = "1.0"
}
ok, err := cwversion.Statisfies(node.FormatVersion, cwversion.Constraint_parser)
if err != nil {
log.Fatalf("Failed to check version : %s", err)
}
if !ok {
log.Errorf("%s doesn't satisfy parser format %s, skip", node.FormatVersion, cwversion.Constraint_parser)
continue
}
node.Stage = stageFile.Stage
if _, ok := tmpstages[stageFile.Stage]; !ok {
tmpstages[stageFile.Stage] = true
}
//compile the node : grok pattern and expression
err = node.compile(pctx)
if err != nil {
if node.Name != "" {
return nil, fmt.Errorf("failed to compile node '%s' in '%s' : %s", node.Name, stageFile.Filename, err.Error())
}
return nil, fmt.Errorf("failed to compile node in '%s' : %s", stageFile.Filename, err.Error())
}
/* if the stage is empty, the node is empty, it's a trailing entry in users yaml file */
if node.Stage == "" {
continue
}
nodes = append(nodes, node)
nodesCount++
}
log.WithFields(log.Fields{"file": stageFile.Filename}).Infof("Loaded %d parser nodes", nodesCount)
}
for k := range tmpstages {
pctx.Stages = append(pctx.Stages, k)
}
sort.Strings(pctx.Stages)
log.Debugf("Stages loaded: %+v", pctx.Stages)
return nodes, nil
}
func LoadStageDir(dir string, pctx *UnixParserCtx) ([]Node, error) {
var files []Stagefile
m, err := filepath.Glob(dir + "/*/*")
if err != nil {
return nil, fmt.Errorf("Unable to find configs in '%s' : %v", dir, err)
}
for _, f := range m {
tmp := Stagefile{}
tmp.Filename = f
//guess stage : (prefix - file).split('/')[0]
stages := strings.Split(f, "/")
stage := stages[len(stages)-2]
tmp.Stage = stage
files = append(files, tmp)
}
return LoadStages(files, pctx)
}