crowdsec/pkg/appsec/appsec_rules_collection.go
2024-01-17 11:54:44 +01:00

144 lines
3.8 KiB
Go

package appsec
import (
"fmt"
"os"
"path/filepath"
"strings"
"github.com/crowdsecurity/crowdsec/pkg/appsec/appsec_rule"
"github.com/crowdsecurity/crowdsec/pkg/exprhelpers"
log "github.com/sirupsen/logrus"
)
type AppsecCollection struct {
collectionName string
Rules []string
}
var APPSEC_RULE = "appsec-rule"
// to be filled w/ seb update
type AppsecCollectionConfig struct {
Type string `yaml:"type"`
Name string `yaml:"name"`
Debug bool `yaml:"debug"`
Description string `yaml:"description"`
SecLangFilesRules []string `yaml:"seclang_files_rules"`
SecLangRules []string `yaml:"seclang_rules"`
Rules []appsec_rule.CustomRule `yaml:"rules"`
Labels map[string]interface{} `yaml:"labels"` //Labels is K:V list aiming at providing context the overflow
Data interface{} `yaml:"data"` //Ignore it
hash string `yaml:"-"`
version string `yaml:"-"`
}
type RulesDetails struct {
LogLevel log.Level
Hash string
Version string
Name string
}
// FIXME: this shouldn't be a global
// Is using the id is a good idea ? might be too specific to coraza and not easily reusable
var AppsecRulesDetails = make(map[int]RulesDetails)
func LoadCollection(pattern string, logger *log.Entry) ([]AppsecCollection, error) {
ret := make([]AppsecCollection, 0)
for _, appsecRule := range appsecRules {
tmpMatch, err := exprhelpers.Match(pattern, appsecRule.Name)
if err != nil {
logger.Errorf("unable to match %s with %s : %s", appsecRule.Name, pattern, err)
continue
}
matched, ok := tmpMatch.(bool)
if !ok {
logger.Errorf("unable to match %s with %s : %s", appsecRule.Name, pattern, err)
continue
}
if !matched {
continue
}
appsecCol := AppsecCollection{
collectionName: appsecRule.Name,
}
if appsecRule.SecLangFilesRules != nil {
for _, rulesFile := range appsecRule.SecLangFilesRules {
logger.Debugf("Adding rules from %s", rulesFile)
fullPath := filepath.Join(hub.GetDataDir(), rulesFile)
c, err := os.ReadFile(fullPath)
if err != nil {
logger.Errorf("unable to read file %s : %s", rulesFile, err)
continue
}
for _, line := range strings.Split(string(c), "\n") {
if strings.HasPrefix(line, "#") {
continue
}
if strings.TrimSpace(line) == "" {
continue
}
appsecCol.Rules = append(appsecCol.Rules, line)
}
}
}
if appsecRule.SecLangRules != nil {
logger.Tracef("Adding inline rules %+v", appsecRule.SecLangRules)
appsecCol.Rules = append(appsecCol.Rules, appsecRule.SecLangRules...)
}
if appsecRule.Rules != nil {
for _, rule := range appsecRule.Rules {
strRule, rulesId, err := rule.Convert(appsec_rule.ModsecurityRuleType, appsecRule.Name)
if err != nil {
logger.Errorf("unable to convert rule %s : %s", appsecRule.Name, err)
return nil, err
}
logger.Debugf("Adding rule %s", strRule)
appsecCol.Rules = append(appsecCol.Rules, strRule)
//We only take the first id, as it's the one of the "main" rule
if _, ok := AppsecRulesDetails[int(rulesId[0])]; !ok {
AppsecRulesDetails[int(rulesId[0])] = RulesDetails{
LogLevel: log.InfoLevel,
Hash: appsecRule.hash,
Version: appsecRule.version,
Name: appsecRule.Name,
}
} else {
logger.Warnf("conflicting id %d for rule %s !", rulesId[0], rule.Name)
}
for _, id := range rulesId {
SetRuleDebug(int(id), appsecRule.Debug)
}
}
}
ret = append(ret, appsecCol)
}
if len(ret) == 0 {
return nil, fmt.Errorf("no appsec-rules found for pattern %s", pattern)
}
return ret, nil
}
func (w AppsecCollection) String() string {
ret := ""
for _, rule := range w.Rules {
ret += rule + "\n"
}
return ret
}