TheArchive/tailscale
1
0
Fork 0
mirror of https://github.com/tailscale/tailscale.git synced 2025-12-01 17:49:02 +00:00
Code Issues Packages Projects Releases Wiki Activity

cli: add tailscale dns query (#13368)

Browse Source 
Updates tailscale/tailscale#13326

Adds a CLI subcommand to perform DNS queries using the internal DNS forwarder and observe its internals (namely, which upstream resolvers are being used).

Signed-off-by: Andrea Gottardo <andrea@gottardo.me>
This commit is contained in:
Andrea Gottardo
2024-09-24 13:18:45 -07:00
committed by GitHub
parent a98f75b783
commit 8a6f48b455
13 changed files with 396 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
client/tailscale/apitype/apitype.go
View File

@@ -4,7 +4,10 @@
// Package apitype contains types for the Tailscale LocalAPI and control plane API.
package apitype
import "tailscale.com/tailcfg"
import (
"tailscale.com/tailcfg"
"tailscale.com/types/dnstype"
)
// LocalAPIHost is the Host header value used by the LocalAPI.
const LocalAPIHost = "local-tailscaled.sock"
@@ -65,3 +68,11 @@ type DNSOSConfig struct {
SearchDomains []string
MatchDomains []string
}
// DNSQueryResponse is the response to a DNS query request sent via LocalAPI.
type DNSQueryResponse struct {
// Bytes is the raw DNS response bytes.
Bytes []byte
// Resolvers is the list of resolvers that the forwarder deemed able to resolve the query.
Resolvers []*dnstype.Resolver
}

18
client/tailscale/localclient.go
View File

@@ -37,6 +37,7 @@ import (
"tailscale.com/safesocket"
"tailscale.com/tailcfg"
"tailscale.com/tka"
"tailscale.com/types/dnstype"
"tailscale.com/types/key"
"tailscale.com/types/tkatype"
)
@@ -813,6 +814,8 @@ func (lc *LocalClient) EditPrefs(ctx context.Context, mp *ipn.MaskedPrefs) (*ipn
return decodeJSON[*ipn.Prefs](body)
}
// GetDNSOSConfig returns the system DNS configuration for the current device.
// That is, it returns the DNS configuration that the system would use if Tailscale weren't being used.
func (lc *LocalClient) GetDNSOSConfig(ctx context.Context) (*apitype.DNSOSConfig, error) {
body, err := lc.get200(ctx, "/localapi/v0/dns-osconfig")
if err != nil {
@@ -825,6 +828,21 @@ func (lc *LocalClient) GetDNSOSConfig(ctx context.Context) (*apitype.DNSOSConfig
return &osCfg, nil
}
// QueryDNS executes a DNS query for a name (`google.com.`) and query type (`CNAME`).
// It returns the raw DNS response bytes and the resolvers that were used to answer the query
// (often just one, but can be more if we raced multiple resolvers).
func (lc *LocalClient) QueryDNS(ctx context.Context, name string, queryType string) (bytes []byte, resolvers []*dnstype.Resolver, err error) {
body, err := lc.get200(ctx, fmt.Sprintf("/localapi/v0/dns-query?name=%s&type=%s", url.QueryEscape(name), queryType))
if err != nil {
return nil, nil, err
}
var res apitype.DNSQueryResponse
if err := json.Unmarshal(body, &res); err != nil {
return nil, nil, fmt.Errorf("invalid query response: %w", err)
}
return res.Bytes, res.Resolvers, nil
}
// StartLoginInteractive starts an interactive login.
func (lc *LocalClient) StartLoginInteractive(ctx context.Context) error {
_, err := lc.send(ctx, "POST", "/localapi/v0/login-interactive", http.StatusNoContent, nil)