Files
cgrates/agents/dnsagent.go
2019-09-04 12:24:25 +02:00

324 lines
11 KiB
Go

/*
Real-time Online/Offline Charging System (OCS) for Telecom & ISP environments
Copyright (C) ITsysCOM GmbH
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>
*/
package agents
import (
"fmt"
"strings"
"github.com/cgrates/cgrates/config"
"github.com/cgrates/cgrates/engine"
"github.com/cgrates/cgrates/sessions"
"github.com/cgrates/cgrates/utils"
"github.com/cgrates/rpcclient"
"github.com/miekg/dns"
)
// NewDNSAgent is the constructor for DNSAgent
func NewDNSAgent(cgrCfg *config.CGRConfig, fltrS *engine.FilterS,
sS rpcclient.RpcClientConnection) (da *DNSAgent, err error) {
da = &DNSAgent{cgrCfg: cgrCfg, fltrS: fltrS, sS: sS}
return
}
// DNSAgent translates DNS requests towards CGRateS infrastructure
type DNSAgent struct {
cgrCfg *config.CGRConfig // loaded CGRateS configuration
fltrS *engine.FilterS // connection towards FilterS
sS rpcclient.RpcClientConnection // connection towards CGR-SessionS component
}
// ListenAndServe will run the DNS handler doing also the connection to listen address
func (da *DNSAgent) ListenAndServe() error {
utils.Logger.Info(fmt.Sprintf("<%s> start listening on <%s:%s>",
utils.DNSAgent, da.cgrCfg.DNSAgentCfg().ListenNet, da.cgrCfg.DNSAgentCfg().Listen))
if strings.HasSuffix(da.cgrCfg.DNSAgentCfg().ListenNet, utils.TLSNoCaps) {
return dns.ListenAndServeTLS(
da.cgrCfg.DNSAgentCfg().Listen,
da.cgrCfg.TlsCfg().ServerCerificate,
da.cgrCfg.TlsCfg().ServerKey,
dns.HandlerFunc(
func(w dns.ResponseWriter, m *dns.Msg) {
go da.handleMessage(w, m)
}),
)
}
return dns.ListenAndServe(
da.cgrCfg.DNSAgentCfg().Listen,
da.cgrCfg.DNSAgentCfg().ListenNet,
dns.HandlerFunc(
func(w dns.ResponseWriter, m *dns.Msg) {
go da.handleMessage(w, m)
}),
)
}
// handleMessage is the entry point of all DNS requests
// requests are reaching here asynchronously
func (da *DNSAgent) handleMessage(w dns.ResponseWriter, req *dns.Msg) {
dnsDP := newDNSDataProvider(req, w)
reqVars := make(map[string]interface{})
reqVars[QueryType] = dns.TypeToString[req.Question[0].Qtype]
rply := new(dns.Msg)
rply.SetReply(req)
// message preprocesing
switch req.Question[0].Qtype {
case dns.TypeNAPTR:
reqVars[QueryName] = req.Question[0].Name
e164, err := e164FromNAPTR(req.Question[0].Name)
if err != nil {
utils.Logger.Warning(
fmt.Sprintf("<%s> decoding NAPTR query: <%s>, err: %s",
utils.DNSAgent, req.Question[0].Name, err.Error()))
rply.Rcode = dns.RcodeServerFailure
dnsWriteMsg(w, rply)
return
}
reqVars[E164Address] = e164
reqVars[DomainName] = domainNameFromNAPTR(req.Question[0].Name)
}
cgrRplyNM := config.NewNavigableMap(nil)
rplyNM := config.NewNavigableMap(nil) // share it among different processors
var processed bool
var err error
for _, reqProcessor := range da.cgrCfg.DNSAgentCfg().RequestProcessors {
var lclProcessed bool
lclProcessed, err = da.processRequest(
reqProcessor,
NewAgentRequest(
dnsDP, reqVars, cgrRplyNM, rplyNM,
reqProcessor.Tenant,
da.cgrCfg.GeneralCfg().DefaultTenant,
utils.FirstNonEmpty(da.cgrCfg.DNSAgentCfg().Timezone,
da.cgrCfg.GeneralCfg().DefaultTimezone),
da.fltrS))
if lclProcessed {
processed = lclProcessed
}
if err != nil ||
(lclProcessed && !reqProcessor.Continue) {
break
}
}
if err != nil {
utils.Logger.Warning(
fmt.Sprintf("<%s> error: %s processing message: %s from %s",
utils.DNSAgent, err.Error(), req, w.RemoteAddr()))
rply.Rcode = dns.RcodeServerFailure
dnsWriteMsg(w, rply)
return
} else if !processed {
utils.Logger.Warning(
fmt.Sprintf("<%s> no request processor enabled, ignoring message %s from %s",
utils.DNSAgent, req, w.RemoteAddr()))
rply.Rcode = dns.RcodeServerFailure
dnsWriteMsg(w, rply)
return
}
if err = updateDNSMsgFromNM(rply, rplyNM); err != nil {
utils.Logger.Warning(
fmt.Sprintf("<%s> error: %s updating answer: %s from NM %s",
utils.DNSAgent, err.Error(), utils.ToJSON(rply), utils.ToJSON(rplyNM)))
rply.Rcode = dns.RcodeServerFailure
dnsWriteMsg(w, rply)
return
}
if err = dnsWriteMsg(w, rply); err != nil { // failed sending, most probably content issue
rply = new(dns.Msg)
rply.SetReply(req)
rply.Rcode = dns.RcodeServerFailure
dnsWriteMsg(w, rply)
}
return
}
func (da *DNSAgent) processRequest(reqProcessor *config.RequestProcessor,
agReq *AgentRequest) (processed bool, err error) {
if pass, err := da.fltrS.Pass(agReq.Tenant,
reqProcessor.Filters, agReq); err != nil || !pass {
return pass, err
}
if agReq.CGRRequest, err = agReq.AsNavigableMap(reqProcessor.RequestFields); err != nil {
return
}
cgrEv := agReq.CGRRequest.AsCGREvent(agReq.Tenant, utils.NestingSep)
var reqType string
for _, typ := range []string{
utils.MetaDryRun, utils.MetaAuth,
utils.MetaInitiate, utils.MetaUpdate,
utils.MetaTerminate, utils.MetaMessage,
utils.MetaCDRs, utils.MetaEvent, utils.META_NONE} {
if reqProcessor.Flags.HasKey(typ) { // request type is identified through flags
reqType = typ
break
}
}
cgrArgs := cgrEv.ConsumeArgs(reqProcessor.Flags.HasKey(utils.MetaDispatchers),
reqType == utils.MetaAuth || reqType == utils.MetaMessage || reqType == utils.MetaEvent)
if reqProcessor.Flags.HasKey(utils.MetaLog) {
utils.Logger.Info(
fmt.Sprintf("<%s> LOG, processorID: <%s>, message: %s",
utils.DNSAgent, reqProcessor.ID, agReq.Request.String()))
}
switch reqType {
default:
return false, fmt.Errorf("unknown request type: <%s>", reqType)
case utils.META_NONE: // do nothing on CGRateS side
case utils.MetaDryRun:
utils.Logger.Info(
fmt.Sprintf("<%s> DRY_RUN, processorID: %s, CGREvent: %s",
utils.DNSAgent, reqProcessor.ID, utils.ToJSON(cgrEv)))
case utils.MetaAuth:
authArgs := sessions.NewV1AuthorizeArgs(
reqProcessor.Flags.HasKey(utils.MetaAttributes),
reqProcessor.Flags.ParamsSlice(utils.MetaAttributes),
reqProcessor.Flags.HasKey(utils.MetaThresholds),
reqProcessor.Flags.ParamsSlice(utils.MetaThresholds),
reqProcessor.Flags.HasKey(utils.MetaStats),
reqProcessor.Flags.ParamsSlice(utils.MetaStats),
reqProcessor.Flags.HasKey(utils.MetaResources),
reqProcessor.Flags.HasKey(utils.MetaAccounts),
reqProcessor.Flags.HasKey(utils.MetaSuppliers),
reqProcessor.Flags.HasKey(utils.MetaSuppliersIgnoreErrors),
reqProcessor.Flags.HasKey(utils.MetaSuppliersEventCost),
cgrEv, cgrArgs.ArgDispatcher, *cgrArgs.SupplierPaginator,
)
rply := new(sessions.V1AuthorizeReply)
err = da.sS.Call(utils.SessionSv1AuthorizeEvent,
authArgs, rply)
if err = agReq.setCGRReply(rply, err); err != nil {
return
}
case utils.MetaInitiate:
initArgs := sessions.NewV1InitSessionArgs(
reqProcessor.Flags.HasKey(utils.MetaAttributes),
reqProcessor.Flags.ParamsSlice(utils.MetaAttributes),
reqProcessor.Flags.HasKey(utils.MetaThresholds),
reqProcessor.Flags.ParamsSlice(utils.MetaThresholds),
reqProcessor.Flags.HasKey(utils.MetaStats),
reqProcessor.Flags.ParamsSlice(utils.MetaStats),
reqProcessor.Flags.HasKey(utils.MetaResources),
reqProcessor.Flags.HasKey(utils.MetaAccounts),
cgrEv, cgrArgs.ArgDispatcher)
rply := new(sessions.V1InitSessionReply)
err = da.sS.Call(utils.SessionSv1InitiateSession,
initArgs, rply)
if err = agReq.setCGRReply(rply, err); err != nil {
return
}
case utils.MetaUpdate:
updateArgs := sessions.NewV1UpdateSessionArgs(
reqProcessor.Flags.HasKey(utils.MetaAttributes),
reqProcessor.Flags.ParamsSlice(utils.MetaAttributes),
reqProcessor.Flags.HasKey(utils.MetaAccounts),
cgrEv, cgrArgs.ArgDispatcher)
rply := new(sessions.V1UpdateSessionReply)
err = da.sS.Call(utils.SessionSv1UpdateSession,
updateArgs, rply)
if err = agReq.setCGRReply(rply, err); err != nil {
return
}
case utils.MetaTerminate:
terminateArgs := sessions.NewV1TerminateSessionArgs(
reqProcessor.Flags.HasKey(utils.MetaAccounts),
reqProcessor.Flags.HasKey(utils.MetaResources),
reqProcessor.Flags.HasKey(utils.MetaThresholds),
reqProcessor.Flags.ParamsSlice(utils.MetaThresholds),
reqProcessor.Flags.HasKey(utils.MetaStats),
reqProcessor.Flags.ParamsSlice(utils.MetaStats),
cgrEv, cgrArgs.ArgDispatcher)
rply := utils.StringPointer("")
err = da.sS.Call(utils.SessionSv1TerminateSession,
terminateArgs, rply)
if err = agReq.setCGRReply(nil, err); err != nil {
return
}
case utils.MetaMessage:
evArgs := sessions.NewV1ProcessMessageArgs(
reqProcessor.Flags.HasKey(utils.MetaAttributes),
reqProcessor.Flags.ParamsSlice(utils.MetaAttributes),
reqProcessor.Flags.HasKey(utils.MetaThresholds),
reqProcessor.Flags.ParamsSlice(utils.MetaThresholds),
reqProcessor.Flags.HasKey(utils.MetaStats),
reqProcessor.Flags.ParamsSlice(utils.MetaStats),
reqProcessor.Flags.HasKey(utils.MetaResources),
reqProcessor.Flags.HasKey(utils.MetaAccounts),
reqProcessor.Flags.HasKey(utils.MetaSuppliers),
reqProcessor.Flags.HasKey(utils.MetaSuppliersIgnoreErrors),
reqProcessor.Flags.HasKey(utils.MetaSuppliersEventCost),
cgrEv, cgrArgs.ArgDispatcher, *cgrArgs.SupplierPaginator)
rply := new(sessions.V1ProcessMessageReply) // need it so rpcclient can clone
err = da.sS.Call(utils.SessionSv1ProcessMessage,
evArgs, rply)
if utils.ErrHasPrefix(err, utils.RalsErrorPrfx) {
cgrEv.Event[utils.Usage] = 0 // avoid further debits
} else if rply.MaxUsage != nil {
cgrEv.Event[utils.Usage] = *rply.MaxUsage // make sure the CDR reflects the debit
}
if err = agReq.setCGRReply(rply, err); err != nil {
return
}
case utils.MetaEvent:
evArgs := &sessions.V1ProcessEventArgs{
Flags: reqProcessor.Flags.SliceFlags(),
CGREvent: cgrEv,
ArgDispatcher: cgrArgs.ArgDispatcher,
Paginator: *cgrArgs.SupplierPaginator,
}
rply := new(sessions.V1ProcessEventReply)
err = da.sS.Call(utils.SessionSv1ProcessEvent,
evArgs, rply)
if utils.ErrHasPrefix(err, utils.RalsErrorPrfx) {
cgrEv.Event[utils.Usage] = 0 // avoid further debits
} else if rply.MaxUsage != nil {
cgrEv.Event[utils.Usage] = *rply.MaxUsage // make sure the CDR reflects the debit
}
if err = agReq.setCGRReply(rply, err); err != nil {
return
}
case utils.MetaCDRs: // allow CDR processing
}
// separate request so we can capture the Terminate/Event also here
if reqProcessor.Flags.HasKey(utils.MetaCDRs) &&
!reqProcessor.Flags.HasKey(utils.MetaDryRun) {
rplyCDRs := utils.StringPointer("")
if err = da.sS.Call(utils.SessionSv1ProcessCDR,
&utils.CGREventWithArgDispatcher{CGREvent: cgrEv,
ArgDispatcher: cgrArgs.ArgDispatcher}, &rplyCDRs); err != nil {
agReq.CGRReply.Set([]string{utils.Error}, err.Error(), false, false)
}
}
if nM, err := agReq.AsNavigableMap(reqProcessor.ReplyFields); err != nil {
return false, err
} else {
agReq.Reply.Merge(nM)
}
if reqProcessor.Flags.HasKey(utils.MetaLog) {
utils.Logger.Info(
fmt.Sprintf("<%s> LOG, reply: %s",
utils.DNSAgent, agReq.Reply))
}
if reqType == utils.MetaDryRun {
utils.Logger.Info(
fmt.Sprintf("<%s> DRY_RUN, reply: %s",
utils.DNSAgent, agReq.Reply))
}
return true, nil
}