VictoriaMetrics/app/vmauth/auth_config.go
2022-10-26 14:51:02 +03:00

368 lines
9.8 KiB
Go

package main
import (
"encoding/base64"
"flag"
"fmt"
"net/url"
"os"
"regexp"
"strconv"
"strings"
"sync"
"sync/atomic"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/envtemplate"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/fs"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/procutil"
"github.com/VictoriaMetrics/metrics"
"gopkg.in/yaml.v2"
)
var (
authConfigPath = flag.String("auth.config", "", "Path to auth config. It can point either to local file or to http url. "+
"See https://docs.victoriametrics.com/vmauth.html for details on the format of this auth config")
)
// AuthConfig represents auth config.
type AuthConfig struct {
Users []UserInfo `yaml:"users,omitempty"`
}
// UserInfo is user information read from authConfigPath
type UserInfo struct {
Name string `yaml:"name,omitempty"`
BearerToken string `yaml:"bearer_token,omitempty"`
Username string `yaml:"username,omitempty"`
Password string `yaml:"password,omitempty"`
URLPrefix *URLPrefix `yaml:"url_prefix,omitempty"`
URLMap []URLMap `yaml:"url_map,omitempty"`
Headers []Header `yaml:"headers,omitempty"`
requests *metrics.Counter
}
// Header is `Name: Value` http header, which must be added to the proxied request.
type Header struct {
Name string
Value string
}
// UnmarshalYAML unmarshals h from f.
func (h *Header) UnmarshalYAML(f func(interface{}) error) error {
var s string
if err := f(&s); err != nil {
return err
}
n := strings.IndexByte(s, ':')
if n < 0 {
return fmt.Errorf("missing speparator char ':' between Name and Value in the header %q; expected format - 'Name: Value'", s)
}
h.Name = strings.TrimSpace(s[:n])
h.Value = strings.TrimSpace(s[n+1:])
return nil
}
// MarshalYAML marshals h to yaml.
func (h *Header) MarshalYAML() (interface{}, error) {
s := fmt.Sprintf("%s: %s", h.Name, h.Value)
return s, nil
}
// URLMap is a mapping from source paths to target urls.
type URLMap struct {
SrcPaths []*SrcPath `yaml:"src_paths,omitempty"`
URLPrefix *URLPrefix `yaml:"url_prefix,omitempty"`
Headers []Header `yaml:"headers,omitempty"`
}
// SrcPath represents an src path
type SrcPath struct {
sOriginal string
re *regexp.Regexp
}
// URLPrefix represents pased `url_prefix`
type URLPrefix struct {
n uint32
urls []*url.URL
}
func (up *URLPrefix) getNextURL() *url.URL {
n := atomic.AddUint32(&up.n, 1)
idx := n % uint32(len(up.urls))
return up.urls[idx]
}
// UnmarshalYAML unmarshals up from yaml.
func (up *URLPrefix) UnmarshalYAML(f func(interface{}) error) error {
var v interface{}
if err := f(&v); err != nil {
return err
}
var urls []string
switch x := v.(type) {
case string:
urls = []string{x}
case []interface{}:
if len(x) == 0 {
return fmt.Errorf("`url_prefix` must contain at least a single url")
}
us := make([]string, len(x))
for i, xx := range x {
s, ok := xx.(string)
if !ok {
return fmt.Errorf("`url_prefix` must contain array of strings; got %T", xx)
}
us[i] = s
}
urls = us
default:
return fmt.Errorf("unexpected type for `url_prefix`: %T; want string or []string", v)
}
pus := make([]*url.URL, len(urls))
for i, u := range urls {
pu, err := url.Parse(u)
if err != nil {
return fmt.Errorf("cannot unmarshal %q into url: %w", u, err)
}
pus[i] = pu
}
up.urls = pus
return nil
}
// MarshalYAML marshals up to yaml.
func (up *URLPrefix) MarshalYAML() (interface{}, error) {
var b []byte
if len(up.urls) == 1 {
u := up.urls[0].String()
b = strconv.AppendQuote(b, u)
return string(b), nil
}
b = append(b, '[')
for i, pu := range up.urls {
u := pu.String()
b = strconv.AppendQuote(b, u)
if i+1 < len(up.urls) {
b = append(b, ',')
}
}
b = append(b, ']')
return string(b), nil
}
func (sp *SrcPath) match(s string) bool {
prefix, ok := sp.re.LiteralPrefix()
if ok {
// Fast path - literal match
return s == prefix
}
if !strings.HasPrefix(s, prefix) {
return false
}
return sp.re.MatchString(s)
}
// UnmarshalYAML implements yaml.Unmarshaler
func (sp *SrcPath) UnmarshalYAML(f func(interface{}) error) error {
var s string
if err := f(&s); err != nil {
return err
}
sAnchored := "^(?:" + s + ")$"
re, err := regexp.Compile(sAnchored)
if err != nil {
return fmt.Errorf("cannot build regexp from %q: %w", s, err)
}
sp.sOriginal = s
sp.re = re
return nil
}
// MarshalYAML implements yaml.Marshaler.
func (sp *SrcPath) MarshalYAML() (interface{}, error) {
return sp.sOriginal, nil
}
func initAuthConfig() {
if len(*authConfigPath) == 0 {
logger.Fatalf("missing required `-auth.config` command-line flag")
}
// Register SIGHUP handler for config re-read just before readAuthConfig call.
// This guarantees that the config will be re-read if the signal arrives during readAuthConfig call.
// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1240
sighupCh := procutil.NewSighupChan()
m, err := readAuthConfig(*authConfigPath)
if err != nil {
logger.Fatalf("cannot load auth config from `-auth.config=%s`: %s", *authConfigPath, err)
}
authConfig.Store(m)
stopCh = make(chan struct{})
authConfigWG.Add(1)
go func() {
defer authConfigWG.Done()
authConfigReloader(sighupCh)
}()
}
func stopAuthConfig() {
close(stopCh)
authConfigWG.Wait()
}
func authConfigReloader(sighupCh <-chan os.Signal) {
for {
select {
case <-stopCh:
return
case <-sighupCh:
logger.Infof("SIGHUP received; loading -auth.config=%q", *authConfigPath)
m, err := readAuthConfig(*authConfigPath)
if err != nil {
logger.Errorf("failed to load -auth.config=%q; using the last successfully loaded config; error: %s", *authConfigPath, err)
continue
}
authConfig.Store(m)
logger.Infof("Successfully reloaded -auth.config=%q", *authConfigPath)
}
}
}
var authConfig atomic.Value
var authConfigWG sync.WaitGroup
var stopCh chan struct{}
func readAuthConfig(path string) (map[string]*UserInfo, error) {
data, err := fs.ReadFileOrHTTP(path)
if err != nil {
return nil, err
}
m, err := parseAuthConfig(data)
if err != nil {
return nil, fmt.Errorf("cannot parse %q: %w", path, err)
}
logger.Infof("Loaded information about %d users from %q", len(m), path)
return m, nil
}
func parseAuthConfig(data []byte) (map[string]*UserInfo, error) {
var err error
data, err = envtemplate.ReplaceBytes(data)
if err != nil {
return nil, fmt.Errorf("cannot expand environment vars: %w", err)
}
var ac AuthConfig
if err := yaml.UnmarshalStrict(data, &ac); err != nil {
return nil, fmt.Errorf("cannot unmarshal AuthConfig data: %w", err)
}
uis := ac.Users
if len(uis) == 0 {
return nil, fmt.Errorf("`users` section cannot be empty in AuthConfig")
}
byAuthToken := make(map[string]*UserInfo, len(uis))
for i := range uis {
ui := &uis[i]
if ui.BearerToken == "" && ui.Username == "" {
return nil, fmt.Errorf("either bearer_token or username must be set")
}
if ui.BearerToken != "" && ui.Username != "" {
return nil, fmt.Errorf("bearer_token=%q and username=%q cannot be set simultaneously", ui.BearerToken, ui.Username)
}
at1, at2 := getAuthTokens(ui.BearerToken, ui.Username, ui.Password)
if byAuthToken[at1] != nil {
return nil, fmt.Errorf("duplicate auth token found for bearer_token=%q, username=%q: %q", ui.BearerToken, ui.Username, at1)
}
if byAuthToken[at2] != nil {
return nil, fmt.Errorf("duplicate auth token found for bearer_token=%q, username=%q: %q", ui.BearerToken, ui.Username, at2)
}
if ui.URLPrefix != nil {
if err := ui.URLPrefix.sanitize(); err != nil {
return nil, err
}
}
for _, e := range ui.URLMap {
if len(e.SrcPaths) == 0 {
return nil, fmt.Errorf("missing `src_paths` in `url_map`")
}
if e.URLPrefix == nil {
return nil, fmt.Errorf("missing `url_prefix` in `url_map`")
}
if err := e.URLPrefix.sanitize(); err != nil {
return nil, err
}
}
if len(ui.URLMap) == 0 && ui.URLPrefix == nil {
return nil, fmt.Errorf("missing `url_prefix`")
}
if ui.BearerToken != "" {
name := "bearer_token"
if ui.Name != "" {
name = ui.Name
}
if ui.Password != "" {
return nil, fmt.Errorf("password shouldn't be set for bearer_token %q", ui.BearerToken)
}
ui.requests = metrics.GetOrCreateCounter(fmt.Sprintf(`vmauth_user_requests_total{username=%q}`, name))
}
if ui.Username != "" {
name := ui.Username
if ui.Name != "" {
name = ui.Name
}
ui.requests = metrics.GetOrCreateCounter(fmt.Sprintf(`vmauth_user_requests_total{username=%q}`, name))
}
byAuthToken[at1] = ui
byAuthToken[at2] = ui
}
return byAuthToken, nil
}
func getAuthTokens(bearerToken, username, password string) (string, string) {
if bearerToken != "" {
// Accept the bearerToken as Basic Auth username with empty password
at1 := getAuthToken(bearerToken, "", "")
at2 := getAuthToken("", bearerToken, "")
return at1, at2
}
at := getAuthToken("", username, password)
return at, at
}
func getAuthToken(bearerToken, username, password string) string {
if bearerToken != "" {
return "Bearer " + bearerToken
}
token := username + ":" + password
token64 := base64.StdEncoding.EncodeToString([]byte(token))
return "Basic " + token64
}
func (up *URLPrefix) sanitize() error {
for i, pu := range up.urls {
puNew, err := sanitizeURLPrefix(pu)
if err != nil {
return err
}
up.urls[i] = puNew
}
return nil
}
func sanitizeURLPrefix(urlPrefix *url.URL) (*url.URL, error) {
// Remove trailing '/' from urlPrefix
for strings.HasSuffix(urlPrefix.Path, "/") {
urlPrefix.Path = urlPrefix.Path[:len(urlPrefix.Path)-1]
}
// Validate urlPrefix
if urlPrefix.Scheme != "http" && urlPrefix.Scheme != "https" {
return nil, fmt.Errorf("unsupported scheme for `url_prefix: %q`: %q; must be `http` or `https`", urlPrefix, urlPrefix.Scheme)
}
if urlPrefix.Host == "" {
return nil, fmt.Errorf("missing hostname in `url_prefix %q`", urlPrefix.Host)
}
return urlPrefix, nil
}