Files
benzheng 4c5e192954 feat: verify DSM HTTPS certificate to prevent credential exposure
The DSM WebAPI client disabled TLS certificate verification for all
HTTPS connections (InsecureSkipVerify: true), then sent the configured
DSM account and password to the endpoint. An attacker able to intercept,
redirect, or impersonate the DSM HTTPS endpoint could therefore obtain
the DSM credentials stored in the CSI client config / Kubernetes secret
(CWE-295 Improper Certificate Validation, OWASP A3:2017 Sensitive Data Exposure)

TLS certificate verification is now enabled by default. The client trusts
the system CA pool, so certificates signed by a public CA work without
extra configuration. Three optional client-info fields are added:

  - tlsCACert:          PEM CA cert to trust (for DSM self-signed certs);
                        merged with the system CA pool.
  - tlsServerName:      override the name checked during verification,
                        e.g. when connecting by IP.
  - insecureSkipVerify: explicit opt-out that restores the old behavior;
                        logs a warning on every connection.

The new fields are propagated through all DSM construction sites
(service, synocli, and the HA GetAnotherController path).

BREAKING CHANGE: deployments using `https: true` against a DSM with a
self-signed certificate (the DSM default) will fail to connect after
upgrade until they set `tlsCACert`, `tlsServerName`, or (discouraged)
`insecureSkipVerify: true`.

Adds TLS tests covering default-reject, valid-CA accept, wrong-CA reject,
insecureSkipVerify opt-in, and the tlsServerName DNS-SAN scenarios.
2026-07-29 14:21:55 +08:00

255 lines
5.7 KiB
Go

/*
* Copyright 2021 Synology Inc.
*/
package webapi
import (
"crypto/tls"
"crypto/x509"
"encoding/json"
"fmt"
"io/ioutil"
"net/http"
"net/url"
"regexp"
"github.com/SynologyOpenSource/synology-csi/pkg/logger"
log "github.com/sirupsen/logrus"
)
type DSM struct {
Ip string
Port int
Username string
Password string
Sid string
Https bool
Controller string
TLSCACert string
TLSServerName string
InsecureSkipVerify bool
SystemInfo
}
type SystemInfo struct {
Hostname string
SupportNvmeof bool
FirmwareVer string
}
type errData struct {
Code int `json:"code"`
}
type dsmApiResp struct {
Success bool `json:"success"`
Err errData `json:"error"`
}
type Response struct {
StatusCode int
ErrorCode int
Success bool
Data interface{}
}
func (dsm *DSM) newHTTPClient() (*http.Client, error) {
if !dsm.Https {
return &http.Client{}, nil
}
tlsCfg := &tls.Config{}
if dsm.TLSServerName != "" {
tlsCfg.ServerName = dsm.TLSServerName
}
if dsm.InsecureSkipVerify {
if dsm.TLSCACert != "" {
log.Warnf("tlsCACert is configured but will be ignored for DSM %s because insecureSkipVerify is true.", dsm.Ip)
}
log.Warnf("TLS certificate verification is disabled for DSM %s. "+
"This is insecure; provide tlsCACert instead.", dsm.Ip)
tlsCfg.InsecureSkipVerify = true
} else if dsm.TLSCACert != "" {
pool, err := x509.SystemCertPool()
if err != nil {
log.Warnf("Failed to load system CA pool for DSM %s, falling back to empty pool: %v", dsm.Ip, err)
pool = x509.NewCertPool()
}
if ok := pool.AppendCertsFromPEM([]byte(dsm.TLSCACert)); !ok {
return nil, fmt.Errorf("failed to parse TLS CA certificate for DSM %s", dsm.Ip)
}
tlsCfg.RootCAs = pool
}
tr := http.DefaultTransport.(*http.Transport).Clone()
tr.TLSClientConfig = tlsCfg
return &http.Client{Transport: tr}, nil
}
func (dsm *DSM) sendRequest(data string, apiTemplate interface{}, params url.Values, cgiPath string) (Response, error) {
resp, err := dsm.sendRequestWithoutConnectionCheck(data, apiTemplate, params, cgiPath)
if err != nil && (resp.ErrorCode == 105 || resp.ErrorCode == 106 || resp.ErrorCode == 119) { // 105: WEBAPI_ERR_NO_PERMISSION, 106: session timeout, 119: WEBAPI_ERR_SID_NOT_FOUND
// Re-login
if err := dsm.Login(); err != nil {
return Response{}, fmt.Errorf("Failed to re-login to DSM: [%s]. err: %v", dsm.Ip, err)
}
log.Info("Re-login succeeded.")
return dsm.sendRequestWithoutConnectionCheck(data, apiTemplate, params, cgiPath)
}
return resp, err
}
func (dsm *DSM) sendRequestWithoutConnectionCheck(data string, apiTemplate interface{}, params url.Values, cgiPath string) (Response, error) {
client, err := dsm.newHTTPClient()
if err != nil {
return Response{}, err
}
var req *http.Request
var cgiUrl string
// Ex: http://10.12.12.14:5000/webapi/auth.cgi
if dsm.Https {
cgiUrl = fmt.Sprintf("https://%s:%d/%s", dsm.Ip, dsm.Port, cgiPath)
} else {
cgiUrl = fmt.Sprintf("http://%s:%d/%s", dsm.Ip, dsm.Port, cgiPath)
}
baseUrl, err := url.Parse(cgiUrl)
if err != nil {
return Response{}, err
}
baseUrl.RawQuery = params.Encode()
if logger.WebapiDebug {
log.Debugln(baseUrl.RawQuery)
}
if data != "" {
req, err = http.NewRequest("POST", baseUrl.String(), nil)
} else {
req, err = http.NewRequest("GET", baseUrl.String(), nil)
}
if dsm.Sid != "" {
cookie := http.Cookie{Name: "id", Value: dsm.Sid}
req.AddCookie(&cookie)
}
resp, err := client.Do(req)
if err != nil {
return Response{}, err
}
defer resp.Body.Close()
// For debug print text body
var bodyText []byte
if logger.WebapiDebug {
bodyText, err = ioutil.ReadAll(resp.Body)
if err != nil {
return Response{}, err
}
s := string(bodyText)
log.Debugln(s)
}
if resp.StatusCode != 200 && resp.StatusCode != 302 {
return Response{}, fmt.Errorf("Bad response status code: %d", resp.StatusCode)
}
// Strip data json data from response
type envelop struct {
dsmApiResp
Data json.RawMessage `json:"data"`
}
e := envelop{}
var outResp Response
if logger.WebapiDebug {
if err := json.Unmarshal(bodyText, &e); err != nil {
return Response{}, err
}
} else {
decoder := json.NewDecoder(resp.Body)
if err := decoder.Decode(&e); err != nil {
return Response{}, err
}
}
outResp.Success = e.Success
outResp.ErrorCode = e.Err.Code
outResp.StatusCode = resp.StatusCode
if !e.Success {
return outResp, fmt.Errorf("DSM Api error. Error code:%d", outResp.ErrorCode)
}
if e.Data != nil {
if err := json.Unmarshal(e.Data, apiTemplate); err != nil {
return Response{}, err
}
}
outResp.Data = apiTemplate
if err != nil {
return Response{}, err
}
return outResp, nil
}
// Login by given user name and password
func (dsm *DSM) Login() error {
params := url.Values{}
params.Add("api", "SYNO.API.Auth")
params.Add("method", "login")
params.Add("version", "3")
params.Add("account", dsm.Username)
params.Add("passwd", dsm.Password)
params.Add("format", "sid")
type LoginResp struct {
Sid string `json:"sid"`
}
resp, err := dsm.sendRequestWithoutConnectionCheck("", &LoginResp{}, params, "webapi/auth.cgi")
if err != nil {
r, _ := regexp.Compile("passwd=.*&")
temp := r.ReplaceAllString(err.Error(), "")
return fmt.Errorf("%s", temp)
}
loginResp, ok := resp.Data.(*LoginResp)
if !ok {
return fmt.Errorf("Failed to assert response to %T", &LoginResp{})
}
dsm.Sid = loginResp.Sid
return nil
}
// Logout on current IP and reset the synoToken
func (dsm *DSM) Logout() error {
params := url.Values{}
params.Add("api", "SYNO.API.Auth")
params.Add("method", "logout")
params.Add("version", "1")
_, err := dsm.sendRequestWithoutConnectionCheck("", &struct{}{}, params, "webapi/entry.cgi")
if err != nil {
return err
}
dsm.Sid = ""
return nil
}