mox/tlsrptdb/report.go
Mechiel Lukkien 893a6f8911
implement outgoing tls reports
we were already accepting, processing and displaying incoming tls reports. now
we start tracking TLS connection and security-policy-related errors for
outgoing message deliveries as well. we send reports once a day, to the
reporting addresses specified in TLSRPT records (rua) of a policy domain. these
reports are about MTA-STS policies and/or DANE policies, and about
STARTTLS-related failures.

sending reports is enabled by default, but can be disabled through setting
NoOutgoingTLSReports in mox.conf.

only at the end of the implementation process came the realization that the
TLSRPT policy domain for DANE (MX) hosts are separate from the TLSRPT policy
for the recipient domain, and that MTA-STS and DANE TLS/policy results are
typically delivered in separate reports. so MX hosts need their own TLSRPT
policies.

config for the per-host TLSRPT policy should be added to mox.conf for existing
installs, in field HostTLSRPT. it is automatically configured by quickstart for
new installs. with a HostTLSRPT config, the "dns records" and "dns check" admin
pages now suggest the per-host TLSRPT record. by creating that record, you're
requesting TLS reports about your MX host.

gathering all the TLS/policy results is somewhat tricky. the tentacles go
throughout the code. the positive result is that the TLS/policy-related code
had to be cleaned up a bit. for example, the smtpclient TLS modes now reflect
reality better, with independent settings about whether PKIX and/or DANE
verification has to be done, and/or whether verification errors have to be
ignored (e.g. for tls-required: no header). also, cached mtasts policies of
mode "none" are now cleaned up once the MTA-STS DNS record goes away.
2023-11-09 19:47:26 +01:00

171 lines
5.1 KiB
Go

// Package tlsrptdb stores reports from "SMTP TLS Reporting" in its database.
package tlsrptdb
import (
"context"
"fmt"
"os"
"path/filepath"
"time"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promauto"
"github.com/mjl-/bstore"
"github.com/mjl-/mox/dns"
"github.com/mjl-/mox/mlog"
"github.com/mjl-/mox/mox-"
"github.com/mjl-/mox/tlsrpt"
)
var (
metricSession = promauto.NewCounterVec(
prometheus.CounterOpts{
Name: "mox_tlsrptdb_session_total",
Help: "Number of sessions, both success and known result types.",
},
[]string{"type"}, // Known result types, and "success"
)
knownResultTypes = map[tlsrpt.ResultType]struct{}{
tlsrpt.ResultSTARTTLSNotSupported: {},
tlsrpt.ResultCertificateHostMismatch: {},
tlsrpt.ResultCertificateExpired: {},
tlsrpt.ResultTLSAInvalid: {},
tlsrpt.ResultDNSSECInvalid: {},
tlsrpt.ResultDANERequired: {},
tlsrpt.ResultCertificateNotTrusted: {},
tlsrpt.ResultSTSPolicyInvalid: {},
tlsrpt.ResultSTSWebPKIInvalid: {},
tlsrpt.ResultValidationFailure: {},
tlsrpt.ResultSTSPolicyFetch: {},
}
)
// TLSReportRecord is a TLS report as a database record, including information
// about the sender.
//
// todo: should be named just Record, but it would cause a sherpa type name conflict.
type TLSReportRecord struct {
ID int64 `bstore:"typename Record"`
Domain string `bstore:"index"` // Domain to which the TLS report applies.
FromDomain string
MailFrom string
HostReport bool // Report for host TLSRPT record, as opposed to domain TLSRPT record.
Report tlsrpt.Report
}
func reportDB(ctx context.Context) (rdb *bstore.DB, rerr error) {
mutex.Lock()
defer mutex.Unlock()
if ReportDB == nil {
p := mox.DataDirPath("tlsrpt.db")
os.MkdirAll(filepath.Dir(p), 0770)
db, err := bstore.Open(ctx, p, &bstore.Options{Timeout: 5 * time.Second, Perm: 0660}, ReportDBTypes...)
if err != nil {
return nil, err
}
ReportDB = db
}
return ReportDB, nil
}
// AddReport adds a TLS report to the database.
//
// The report should have come in over SMTP, with a DKIM-validated
// verifiedFromDomain. Using HTTPS for reports is not recommended as there is no
// authentication on the reports origin.
//
// The report is currently required to only cover a single domain in its policy
// domain. Only reports for known domains are added to the database.
//
// Prometheus metrics are updated only for configured domains.
func AddReport(ctx context.Context, verifiedFromDomain dns.Domain, mailFrom string, hostReport bool, r *tlsrpt.Report) error {
log := xlog.WithContext(ctx)
db, err := reportDB(ctx)
if err != nil {
return err
}
if len(r.Policies) == 0 {
return fmt.Errorf("no policies in report")
}
var reportdom, zerodom dns.Domain
record := TLSReportRecord{0, "", verifiedFromDomain.Name(), mailFrom, hostReport, *r}
for _, p := range r.Policies {
pp := p.Policy
// Check domain, they must all be the same for now (in future, with DANE, this may
// no longer apply).
d, err := dns.ParseDomain(pp.Domain)
if err != nil {
log.Errorx("invalid domain in tls report", err, mlog.Field("domain", pp.Domain), mlog.Field("mailfrom", mailFrom))
continue
}
if _, ok := mox.Conf.Domain(d); !ok {
log.Info("unknown domain in tls report, not storing", mlog.Field("domain", d), mlog.Field("mailfrom", mailFrom))
return fmt.Errorf("unknown domain")
}
if reportdom != zerodom && d != reportdom {
return fmt.Errorf("multiple domains in report %s and %s", reportdom, d)
}
reportdom = d
metricSession.WithLabelValues("success").Add(float64(p.Summary.TotalSuccessfulSessionCount))
for _, f := range p.FailureDetails {
var result string
if _, ok := knownResultTypes[f.ResultType]; ok {
result = string(f.ResultType)
} else {
result = "other"
}
metricSession.WithLabelValues(result).Add(float64(f.FailedSessionCount))
}
}
record.Domain = reportdom.Name()
return db.Insert(ctx, &record)
}
// Records returns all TLS reports in the database.
func Records(ctx context.Context) ([]TLSReportRecord, error) {
db, err := reportDB(ctx)
if err != nil {
return nil, err
}
return bstore.QueryDB[TLSReportRecord](ctx, db).List()
}
// RecordID returns the report for the ID.
func RecordID(ctx context.Context, id int64) (TLSReportRecord, error) {
db, err := reportDB(ctx)
if err != nil {
return TLSReportRecord{}, err
}
e := TLSReportRecord{ID: id}
err = db.Get(ctx, &e)
return e, err
}
// RecordsPeriodDomain returns the reports overlapping start and end, for the given
// domain. If domain is empty, all records match for domain.
func RecordsPeriodDomain(ctx context.Context, start, end time.Time, domain string) ([]TLSReportRecord, error) {
db, err := reportDB(ctx)
if err != nil {
return nil, err
}
q := bstore.QueryDB[TLSReportRecord](ctx, db)
if domain != "" {
q.FilterNonzero(TLSReportRecord{Domain: domain})
}
q.FilterFn(func(r TLSReportRecord) bool {
dr := r.Report.DateRange
return !dr.Start.Before(start) && dr.Start.Before(end) || dr.End.After(start) && !dr.End.After(end)
})
return q.List()
}