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Brought back an old friend, the eventual logger
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@shadrick
shadrick committed Jun 6, 2018
1 parent 1283a5f commit a9ec4be
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Showing 2 changed files with 36 additions and 26 deletions.
6 changes: 5 additions & 1 deletion responder/recursive_dns.go
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Original file line number Diff line number Diff line change
Expand Up @@ -1852,9 +1852,13 @@ func handleDNSMessage(loggy *logrus.Entry, provider, network string, rt *runtime

l = l.WithField("domain", r.Question[0].Name)
fLogger, _ := os.Create(RECURSIVE_DNS_FILE_LOGGING_LOCATION + r.Question[0].Name + "." + dns.TypeToString[r.Question[0].Qtype])
rrt := NewResolverRuntime(rt, l, provider, r, 0, 0, fLogger)
rrt := NewResolverRuntime(rt, l, provider, r, 0, 0, fLogger, new(nlog.EventualLogger))
result, e := Resolve(rrt)
if e != nil || result == nil {
if LOGGING == LOGGING_EVENTUALLY {
prefix := fmt.Sprintf("[%s/%s]", rrt.domain, dns.TypeToString[rrt.record])
rrt.eventualLogger.FlushExt(rrt.l, prefix)
}
result = setupResult(rrt, dns.RcodeServerFailure, nil)
}
if !doWeReturnDNSSEC(rrt) && isDNSSECResponse(result) {
Expand Down
56 changes: 31 additions & 25 deletions responder/recursive_dns_resolver.go
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Original file line number Diff line number Diff line change
Expand Up @@ -27,6 +27,7 @@ const (
LOGGING_LOGRUS
LOGGING_PRINTF
LOGGING_FILE
LOGGING_EVENTUALLY
)

const (
Expand All @@ -37,7 +38,7 @@ const (

var (
THREADING = THREADING_NONE
LOGGING = LOGGING_LOGRUS
LOGGING = LOGGING_EVENTUALLY
)

const (
Expand Down Expand Up @@ -116,21 +117,21 @@ type ResolverRuntime struct {
s *runtime.Stats
l *logrus.Entry
/// session specific vars
provider string /// the type of service we provide (opennic/iana roots)
original *dns.Msg /// the original request that came in (aggregated form of all the query flags and parameters)
record uint16 /// requested RR type (miek dns lib format)
domain string /// the original requested domain
zones []string /// tokens of the original domain
currentZone string /// the zone we are currently quering in (it's the parent zone of the current query subject (may be more than one label difference between the two))
prefNet string /// preferred network to use for upstream queries
transactions []*transaction /// a log of all the transactions until an answer is formulated
targetServers map[string][]*entity /// a zone string to available nameservers map (the first level, "." is filled automatically)
redirections []*dns.CNAME /// a collection of all the redirections (that ultimately will make it into the answer section) until an answer can be formulated
blockTracker map[string]int /// a map to track blocked requests
oomAlert int32 /// contrary to what the name says, it's a counter for the number of recursions made (global, per request handler)
oomAlert2 int32 /// same as above, it detects loops in another aspect
fileLogger *os.File /// logger activated when LOGGING is LOGGING_FILE

provider string /// the type of service we provide (opennic/iana roots)
original *dns.Msg /// the original request that came in (aggregated form of all the query flags and parameters)
record uint16 /// requested RR type (miek dns lib format)
domain string /// the original requested domain
zones []string /// tokens of the original domain
currentZone string /// the zone we are currently quering in (it's the parent zone of the current query subject (may be more than one label difference between the two))
prefNet string /// preferred network to use for upstream queries
transactions []*transaction /// a log of all the transactions until an answer is formulated
targetServers map[string][]*entity /// a zone string to available nameservers map (the first level, "." is filled automatically)
redirections []*dns.CNAME /// a collection of all the redirections (that ultimately will make it into the answer section) until an answer can be formulated
blockTracker map[string]int /// a map to track blocked requests
oomAlert int32 /// contrary to what the name says, it's a counter for the number of recursions made (global, per request handler)
oomAlert2 int32 /// same as above, it detects loops in another aspect
fileLogger *os.File /// logger activated when LOGGING is LOGGING_FILE
eventualLogger *log.EventualLogger /// logger which collects lines that are output eventually if an ulterior condition is met (e.g. resolve failure)
}

/// this structure is about an entity, it's primary element is one IP
Expand Down Expand Up @@ -229,7 +230,7 @@ func resolveParallelHarness(rrt *ResolverRuntime, target []*dns.NS) (result []*e
input = append(input, newDNSQuery(ns.Ns, dns.TypeA))
}
if THREADING != THREADING_MAX {
answer, _ := Resolve(NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, input[0], rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger))
answer, _ := Resolve(NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, input[0], rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger, rrt.eventualLogger))
if answer != nil {
answer.Question = input[0].Question
if answer.Answer != nil {
Expand All @@ -248,7 +249,7 @@ func resolveParallelHarness(rrt *ResolverRuntime, target []*dns.NS) (result []*e
achan := make(chan *dns.Msg, len(input))
for _, q := range input {
go func(question *dns.Msg) {
answer, _ := Resolve(NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, question, rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger))
answer, _ := Resolve(NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, question, rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger, rrt.eventualLogger))
if answer != nil {
answer.Question = question.Question
achan <- answer
Expand Down Expand Up @@ -337,7 +338,7 @@ func doQueryParallelHarness(rrt *ResolverRuntime, targetServers []*entity, qname

}

func NewResolverRuntime(rt *runtime.Runtime, lg *logrus.Entry, provider string, incoming *dns.Msg, recursionStats, recursionStats2 int32, fileLogger *os.File) (rrt *ResolverRuntime) {
func NewResolverRuntime(rt *runtime.Runtime, lg *logrus.Entry, provider string, incoming *dns.Msg, recursionStats, recursionStats2 int32, fileLogger *os.File, eventualLogger *log.EventualLogger) (rrt *ResolverRuntime) {
/// normalize incoming query arguments
incoming.Question[0].Name = strings.ToLower(incoming.Question[0].Name)

Expand All @@ -356,6 +357,7 @@ func NewResolverRuntime(rt *runtime.Runtime, lg *logrus.Entry, provider string,
rrt.record = rrt.original.Question[0].Qtype
rrt.transactions = []*transaction{}
rrt.blockTracker = make(map[string]int)
rrt.eventualLogger = eventualLogger
return
}

Expand Down Expand Up @@ -557,10 +559,10 @@ func doQueryRecursively(rrt *ResolverRuntime, _level int) (*dns.Msg, error) {
/// we do a child zone DNSKEY - this can be verified, even if the RRSIG is signed with the queried key, because ve validate DNSKEY first, and then RRSIG
if answerType == RESPONSE_DELEGATION_AUTHORITATIVE && fetchRRByType(res, dns.TypeDS) == nil {
LogInfo(rrt, "Caught an authoritative delegation for [%s]", res.Question[0].String())
rrtDS := NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, newDNSQuery(currentToken, dns.TypeDS), rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger)
rrtDS := NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, newDNSQuery(currentToken, dns.TypeDS), rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger, rrt.eventualLogger)
setupZone(rrtDS, currentToken, extractCommonElements(fetchRRByType(res, dns.TypeNS), rrt.targetServers[currentZone]))
Resolve(rrtDS)
rrtDNSKEY := NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, newDNSQuery(currentToken, dns.TypeDNSKEY), rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger)
rrtDNSKEY := NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, newDNSQuery(currentToken, dns.TypeDNSKEY), rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger, rrt.eventualLogger)
setupZone(rrtDNSKEY, currentToken, extractCommonElements(fetchRRByType(res, dns.TypeNS), rrt.targetServers[currentZone]))
Resolve(rrtDNSKEY)
}
Expand Down Expand Up @@ -685,12 +687,12 @@ func doQueryRecursively(rrt *ResolverRuntime, _level int) (*dns.Msg, error) {
if answerType == RESPONSE_REDIRECT && res.Authoritative && strings.HasSuffix(lastOwner, res.Question[0].Name) {
/// an extra hack for `list.tmall.com` (CNAME resolve loop)
LogInfo(rrt, "Doing the CNAME redirection loop prevention")
rrtCNAME := NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, newDNSQuery(lastOwner, rrt.record), rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger)
rrtCNAME := NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, newDNSQuery(lastOwner, rrt.record), rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger, rrt.eventualLogger)
setupZone(rrtCNAME, lastOwner, rrt.targetServers[currentZone])
redirectResult, err = Resolve(rrtCNAME)
} else {
redirectResult, err = Resolve(NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s},
rrt.l, rrt.provider, newDNSQuery(lastOwner, rrt.record), rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger))
rrt.l, rrt.provider, newDNSQuery(lastOwner, rrt.record), rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger, rrt.eventualLogger))
}

if err != nil {
Expand Down Expand Up @@ -1593,7 +1595,7 @@ func fetchFromCacheOrNetwork(rrt *ResolverRuntime, zone string, record uint16) (
}

/// reaching this point means we cannot serve the answer from cache
networkDS, err := Resolve(NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, newDNSQuery(zone, record), rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger))
networkDS, err := Resolve(NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, newDNSQuery(zone, record), rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger, rrt.eventualLogger))
if err != nil {
return nil, err
} else if networkDS == nil {
Expand Down Expand Up @@ -1630,7 +1632,7 @@ func fetchNSAsEntity(rrt *ResolverRuntime, zone string, resolveNS, resolveA bool
return nil
}
LogInfo(rrt, "fetchNSAsEntity: Retrieving NS records the hard way.")
resolvedNS, _ := Resolve(NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, newDNSQuery(zone, dns.TypeNS), rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger))
resolvedNS, _ := Resolve(NewResolverRuntime(&runtime.Runtime{Cache: rrt.c, IPPool: rrt.p, SlackWH: rrt.f, Stats: rrt.s}, rrt.l, rrt.provider, newDNSQuery(zone, dns.TypeNS), rrt.oomAlert, rrt.oomAlert2, rrt.fileLogger, rrt.eventualLogger))
/// check if we have glue records (if indeed we have, construct the entities array, and return it, else, pass the Ns array further down to processing)
for _, answer := range resolvedNS.Answer {
if ns, ok := answer.(*dns.NS); ok {
Expand Down Expand Up @@ -1833,6 +1835,8 @@ func LogInfo(rrt *ResolverRuntime, format string, args ...interface{}) {
return
} else if LOGGING == LOGGING_LOGRUS {
rrt.l.Infof(format, args...)
} else if LOGGING == LOGGING_EVENTUALLY {
rrt.eventualLogger.Queuef(format, args...)
} else {
rrt.fileLogger.WriteString(fmt.Sprintf(format+"\n", args...))
}
Expand All @@ -1846,6 +1850,8 @@ func LogError(rrt *ResolverRuntime, format string, args ...interface{}) {
return
} else if LOGGING == LOGGING_LOGRUS {
rrt.l.Errorf(format, args...)
} else if LOGGING == LOGGING_EVENTUALLY {
rrt.eventualLogger.Queuef(format, args...)
} else {
rrt.fileLogger.WriteString(fmt.Sprintf(format+"\n", args...))
}
Expand Down

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