checker-ns-restrictions/checker/collect.go

117 lines
3 KiB
Go

package checker
import (
"context"
"encoding/json"
"errors"
"fmt"
"net"
"strings"
"syscall"
"time"
sdk "git.happydns.org/checker-sdk-go/checker"
)
// Collect performs the NS security restriction checks for the configured
// service and returns an NSRestrictionsReport.
func (p *nsProvider) Collect(ctx context.Context, opts sdk.CheckerOptions) (any, error) {
svc, err := serviceFromOptions(opts)
if err != nil {
return nil, err
}
if svc.Type != serviceTypeOrigin && svc.Type != serviceTypeNSOnlyOrigin {
return nil, fmt.Errorf("service is %s, expected %s or %s", svc.Type, serviceTypeOrigin, serviceTypeNSOnlyOrigin)
}
domainName := ""
if v, ok := opts["domainName"]; ok {
if s, ok := v.(string); ok {
domainName = s
}
}
if domainName == "" {
domainName = svc.Domain
}
if domainName == "" {
return nil, fmt.Errorf("domain name not provided and not present in service")
}
nameServers := nsFromService(svc)
if len(nameServers) == 0 {
return nil, fmt.Errorf("no nameservers found in service")
}
report := &NSRestrictionsReport{}
for _, ns := range nameServers {
nsHost := strings.TrimSuffix(ns.Ns, ".")
results := checkNameServer(ctx, domainName, nsHost)
report.Servers = append(report.Servers, results...)
}
return report, nil
}
// serviceFromOptions extracts a *serviceMessage from the options. It accepts
// either a direct value (in-process plugin path) or a JSON-decoded
// map[string]any (HTTP path) — both are normalized via a JSON round-trip.
func serviceFromOptions(opts sdk.CheckerOptions) (*serviceMessage, error) {
v, ok := opts["service"]
if !ok {
return nil, fmt.Errorf("service not defined")
}
raw, err := json.Marshal(v)
if err != nil {
return nil, fmt.Errorf("failed to marshal service option: %w", err)
}
var svc serviceMessage
if err := json.Unmarshal(raw, &svc); err != nil {
return nil, fmt.Errorf("failed to decode service option: %w", err)
}
return &svc, nil
}
// checkNameServer resolves nsHost and runs checks on each address.
func checkNameServer(ctx context.Context, domain, nsHost string) []NSServerResult {
addrs, err := net.LookupHost(nsHost)
if err != nil {
return []NSServerResult{{
Name: nsHost,
Address: "",
Checks: []NSCheckItem{{
Name: "DNS resolution",
OK: false,
Detail: fmt.Sprintf("lookup failed: %s", err),
}},
}}
}
var results []NSServerResult
for _, addr := range addrs {
// Skip IPv6 addresses when there is no IPv6 connectivity.
if ip := net.ParseIP(addr); ip != nil && ip.To4() == nil {
conn, err := net.DialTimeout("udp", net.JoinHostPort(addr, "53"), 3*time.Second)
if errors.Is(err, syscall.ENETUNREACH) {
results = append(results, NSServerResult{
Name: nsHost,
Address: addr,
Checks: []NSCheckItem{{
Name: "IPv6 connectivity",
OK: true,
Detail: "unable to test due to the lack of IPv6 connectivity",
}},
})
continue
}
if conn != nil {
conn.Close()
}
}
results = append(results, checkServerAddr(ctx, domain, nsHost, addr))
}
return results
}