implement SASL OAUTHBEARER and draft/bearer (#2122)

* implement SASL OAUTHBEARER and draft/bearer
* Upgrade JWT lib
* Fix an edge case in SASL EXTERNAL
* Accept longer SASL responses
* review fix: allow multiple token definitions
* enhance tests
* use SASL utilities from irc-go
* test expired tokens

default.yaml

@@ -586,6 +586,40 @@ accounts:
         # how many scripts are allowed to run at once? 0 for no limit:
         max-concurrency: 64
 
+    # support for login via OAuth2 bearer tokens
+    oauth2:
+        enabled: false
+        # should we automatically create users on presentation of a valid token?
+        autocreate: true
+        # enable this to use auth-script for validation:
+        auth-script: false
+        introspection-url: "https://example.com/api/oidc/introspection"
+        introspection-timeout: 10s
+        # omit for auth method `none`; required for auth method `client_secret_basic`:
+        client-id: "ergo"
+        client-secret: "4TA0I7mJ3fUUcW05KJiODg"
+
+    # support for login via JWT bearer tokens
+    jwt-auth:
+        enabled: false
+        # should we automatically create users on presentation of a valid token?
+        autocreate: true
+        # any of these token definitions can be accepted, allowing for key rotation
+        tokens:
+            -
+                algorithm: "hmac" # either 'hmac', 'rsa', or 'eddsa' (ed25519)
+                # hmac takes a symmetric key, rsa and eddsa take PEM-encoded public keys;
+                # either way, the key can be specified either as a YAML string:
+                key: "nANiZ1De4v6WnltCHN2H7Q"
+                # or as a path to the file containing the key:
+                #key-file: "jwt_pubkey.pem"
+                # list of JWT claim names to search for the user's account name (make sure the format
+                # is what you expect, especially if using "sub"):
+                account-claims: ["preferred_username"]
+                # if a claim is formatted as an email address, require it to have the following domain,
+                # and then strip off the domain and use the local-part as the account name:
+                #strip-domain: "example.com"
+
 # channel options
 channels:
     # modes that are set when new channels are created

gencapdefs.py

@@ -219,6 +219,12 @@ CAPDEFS = [
         url="https://github.com/ircv3/ircv3-specifications/pull/527",
         standard="proposed IRCv3",
     ),
+   CapDef(
+        identifier="Bearer",
+        name="draft/bearer",
+        url="https://gist.github.com/slingamn/4fabc7a3d5f335da7bb313a7f0648f37",
+        standard="proposed IRCv3",
+    ),
 ]
 
 def validate_defs():

go.mod

@@ -8,11 +8,10 @@ require (
 	github.com/docopt/docopt-go v0.0.0-20180111231733-ee0de3bc6815
 	github.com/ergochat/confusables v0.0.0-20201108231250-4ab98ab61fb1
 	github.com/ergochat/go-ident v0.0.0-20230911071154-8c30606d6881
-	github.com/ergochat/irc-go v0.4.0
+	github.com/ergochat/irc-go v0.5.0-rc1
 	github.com/go-sql-driver/mysql v1.7.0
 	github.com/go-test/deep v1.0.6 // indirect
 	github.com/gofrs/flock v0.8.1
-	github.com/golang-jwt/jwt v3.2.2+incompatible
 	github.com/gorilla/websocket v1.4.2
 	github.com/okzk/sdnotify v0.0.0-20180710141335-d9becc38acbd
 	github.com/onsi/ginkgo v1.12.0 // indirect
@@ -27,6 +26,8 @@ require (
 	gopkg.in/yaml.v2 v2.4.0
 )
 
+require github.com/golang-jwt/jwt/v5 v5.2.0
+
 require (
 	github.com/tidwall/btree v1.4.2 // indirect
 	github.com/tidwall/gjson v1.14.3 // indirect

go.sum

@@ -12,6 +12,8 @@ github.com/ergochat/go-ident v0.0.0-20230911071154-8c30606d6881 h1:+J5m88nvybxB5
 github.com/ergochat/go-ident v0.0.0-20230911071154-8c30606d6881/go.mod h1:ASYJtQujNitna6cVHsNQTGrfWvMPJ5Sa2lZlmsH65uM=
 github.com/ergochat/irc-go v0.4.0 h1:0YibCKfAAtwxQdNjLQd9xpIEPisLcJ45f8FNsMHAuZc=
 github.com/ergochat/irc-go v0.4.0/go.mod h1:2vi7KNpIPWnReB5hmLpl92eMywQvuIeIIGdt/FQCph0=
+github.com/ergochat/irc-go v0.5.0-rc1 h1:kFoIHExoNFQ2CV+iShAVna/H4xrXQB4t4jK5Sep2j9k=
+github.com/ergochat/irc-go v0.5.0-rc1/go.mod h1:2vi7KNpIPWnReB5hmLpl92eMywQvuIeIIGdt/FQCph0=
 github.com/ergochat/scram v1.0.2-ergo1 h1:2bYXiRFQH636pT0msOG39fmEYl4Eq+OuutcyDsCix/g=
 github.com/ergochat/scram v1.0.2-ergo1/go.mod h1:1WAq6h33pAW+iRreB34OORO2Nf7qel3VV3fjBj+hCSs=
 github.com/ergochat/websocket v1.4.2-oragono1 h1:plMUunFBM6UoSCIYCKKclTdy/TkkHfUslhOfJQzfueM=
@@ -23,8 +25,8 @@ github.com/go-test/deep v1.0.6 h1:UHSEyLZUwX9Qoi99vVwvewiMC8mM2bf7XEM2nqvzEn8=
 github.com/go-test/deep v1.0.6/go.mod h1:QV8Hv/iy04NyLBxAdO9njL0iVPN1S4d/A3NVv1V36o8=
 github.com/gofrs/flock v0.8.1 h1:+gYjHKf32LDeiEEFhQaotPbLuUXjY5ZqxKgXy7n59aw=
 github.com/gofrs/flock v0.8.1/go.mod h1:F1TvTiK9OcQqauNUHlbJvyl9Qa1QvF/gOUDKA14jxHU=
-github.com/golang-jwt/jwt v3.2.2+incompatible h1:IfV12K8xAKAnZqdXVzCZ+TOjboZ2keLg81eXfW3O+oY=
-github.com/golang-jwt/jwt v3.2.2+incompatible/go.mod h1:8pz2t5EyA70fFQQSrl6XZXzqecmYZeUEB8OUGHkxJ+I=
+github.com/golang-jwt/jwt/v5 v5.2.0 h1:d/ix8ftRUorsN+5eMIlF4T6J8CAt9rch3My2winC1Jw=
+github.com/golang-jwt/jwt/v5 v5.2.0/go.mod h1:pqrtFR0X4osieyHYxtmOUWsAWrfe1Q5UVIyoH402zdk=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/hpcloud/tail v1.0.0 h1:nfCOvKYfkgYP8hkirhJocXT2+zOD8yUNjXaWfTlyFKI=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=

irc/accounts.go

@@ -4,6 +4,7 @@
 package irc
 
 import (
+	"context"
 	"crypto/rand"
 	"crypto/x509"
 	"encoding/json"
@@ -19,10 +20,12 @@ import (
 	"github.com/tidwall/buntdb"
 	"github.com/xdg-go/scram"
 
+	"github.com/ergochat/ergo/irc/caps"
 	"github.com/ergochat/ergo/irc/connection_limits"
 	"github.com/ergochat/ergo/irc/email"
 	"github.com/ergochat/ergo/irc/migrations"
 	"github.com/ergochat/ergo/irc/modes"
+	"github.com/ergochat/ergo/irc/oauth2"
 	"github.com/ergochat/ergo/irc/passwd"
 	"github.com/ergochat/ergo/irc/utils"
 )
@@ -1395,6 +1398,10 @@ func (am *AccountManager) AuthenticateByPassphrase(client *Client, accountName s
 		}
 	}
 
+	if strings.HasPrefix(accountName, caps.BearerTokenPrefix) {
+		return am.AuthenticateByBearerToken(client, strings.TrimPrefix(accountName, caps.BearerTokenPrefix), passphrase)
+	}
+
 	if throttled, remainingTime := client.checkLoginThrottle(); throttled {
 		return &ThrottleError{remainingTime}
 	}
@@ -1427,6 +1434,71 @@ func (am *AccountManager) AuthenticateByPassphrase(client *Client, accountName s
 	return err
 }
 
+func (am *AccountManager) AuthenticateByBearerToken(client *Client, tokenType, token string) (err error) {
+	switch tokenType {
+	case "oauth2":
+		return am.AuthenticateByOAuthBearer(client, oauth2.OAuthBearerOptions{Token: token})
+	case "jwt":
+		return am.AuthenticateByJWT(client, token)
+	default:
+		return errInvalidBearerTokenType
+	}
+}
+
+func (am *AccountManager) AuthenticateByOAuthBearer(client *Client, opts oauth2.OAuthBearerOptions) (err error) {
+	config := am.server.Config()
+
+	// we need to check this here since we can get here via SASL PLAIN:
+	if !config.Accounts.OAuth2.Enabled {
+		return errFeatureDisabled
+	}
+
+	var username string
+	if config.Accounts.AuthScript.Enabled && config.Accounts.OAuth2.AuthScript {
+		username, err = am.authenticateByOAuthBearerScript(client, config, opts)
+	} else {
+		username, err = config.Accounts.OAuth2.Introspect(context.Background(), opts.Token)
+	}
+	if err != nil {
+		return err
+	}
+
+	account, err := am.loadWithAutocreation(username, config.Accounts.OAuth2.Autocreate)
+	if err == nil {
+		am.Login(client, account)
+	}
+	return err
+}
+
+func (am *AccountManager) AuthenticateByJWT(client *Client, token string) (err error) {
+	config := am.server.Config()
+	// enabled check is encapsulated here:
+	accountName, err := config.Accounts.JWTAuth.Validate(token)
+	if err != nil {
+		am.server.logger.Debug("accounts", "invalid JWT token", err.Error())
+		return errAccountInvalidCredentials
+	}
+	account, err := am.loadWithAutocreation(accountName, config.Accounts.JWTAuth.Autocreate)
+	if err == nil {
+		am.Login(client, account)
+	}
+	return err
+}
+
+func (am *AccountManager) authenticateByOAuthBearerScript(client *Client, config *Config, opts oauth2.OAuthBearerOptions) (username string, err error) {
+	output, err := CheckAuthScript(am.server.semaphores.AuthScript, config.Accounts.AuthScript.ScriptConfig,
+		AuthScriptInput{OAuthBearer: &opts, IP: client.IP().String()})
+
+	if err != nil {
+		am.server.logger.Error("internal", "failed shell auth invocation", err.Error())
+		return "", oauth2.ErrInvalidToken
+	} else if output.Success {
+		return output.AccountName, nil
+	} else {
+		return "", oauth2.ErrInvalidToken
+	}
+}
+
 // AllNicks returns the uncasefolded nicknames for all accounts, including additional (grouped) nicks.
 func (am *AccountManager) AllNicks() (result []string) {
 	accountNamePrefix := fmt.Sprintf(keyAccountName, "")
@@ -1939,8 +2011,10 @@ func (am *AccountManager) AuthenticateByCertificate(client *Client, certfp strin
 		return err
 	}
 
-	if authzid != "" && authzid != account {
-		return errAuthzidAuthcidMismatch
+	if authzid != "" {
+		if cfAuthzid, err := CasefoldName(authzid); err != nil || cfAuthzid != account {
+			return errAuthzidAuthcidMismatch
+		}
 	}
 
 	// ok, we found an account corresponding to their certificate
@@ -2145,6 +2219,7 @@ var (
 		"PLAIN":         authPlainHandler,
 		"EXTERNAL":      authExternalHandler,
 		"SCRAM-SHA-256": authScramHandler,
+		"OAUTHBEARER":   authOauthBearerHandler,
 	}
 )
 

irc/authscript.go

@@ -10,6 +10,7 @@ import (
 	"fmt"
 	"net"
 
+	"github.com/ergochat/ergo/irc/oauth2"
 	"github.com/ergochat/ergo/irc/utils"
 )
 
@@ -20,7 +21,8 @@ type AuthScriptInput struct {
 	Certfp      string   `json:"certfp,omitempty"`
 	PeerCerts   []string `json:"peerCerts,omitempty"`
 	peerCerts   []*x509.Certificate
-	IP          string `json:"ip,omitempty"`
+	IP          string                     `json:"ip,omitempty"`
+	OAuthBearer *oauth2.OAuthBearerOptions `json:"oauth2,omitempty"`
 }
 
 type AuthScriptOutput struct {

irc/caps/constants.go

@@ -64,6 +64,10 @@ const (
 	BotTagName = "bot"
 	// https://ircv3.net/specs/extensions/chathistory
 	ChathistoryTargetsBatchType = "draft/chathistory-targets"
+
+	// draft/bearer defines this prefix namespace for authcids, enabling tunneling bearer tokens
+	// in SASL PLAIN:
+	BearerTokenPrefix = "*bearer*"
 )
 
 func init() {

irc/caps/defs.go

@@ -7,7 +7,7 @@ package caps
 
 const (
 	// number of recognized capabilities:
-	numCapabs = 34
+	numCapabs = 35
 	// length of the uint32 array that represents the bitset:
 	bitsetLen = 2
 )
@@ -41,6 +41,10 @@ const (
 	// https://github.com/ircv3/ircv3-specifications/pull/435
 	AccountRegistration Capability = iota
 
+	// Bearer is the proposed IRCv3 capability named "draft/bearer":
+	// https://gist.github.com/slingamn/4fabc7a3d5f335da7bb313a7f0648f37
+	Bearer Capability = iota
+
 	// ChannelRename is the draft IRCv3 capability named "draft/channel-rename":
 	// https://ircv3.net/specs/extensions/channel-rename
 	ChannelRename Capability = iota
@@ -160,6 +164,7 @@ var (
 		"cap-notify",
 		"chghost",
 		"draft/account-registration",
+		"draft/bearer",
 		"draft/channel-rename",
 		"draft/chathistory",
 		"draft/event-playback",

irc/client.go

@@ -21,6 +21,7 @@ import (
 	"github.com/ergochat/irc-go/ircfmt"
 	"github.com/ergochat/irc-go/ircmsg"
 	"github.com/ergochat/irc-go/ircreader"
+	"github.com/ergochat/irc-go/ircutils"
 	"github.com/xdg-go/scram"
 
 	"github.com/ergochat/ergo/irc/caps"
@@ -28,6 +29,7 @@ import (
 	"github.com/ergochat/ergo/irc/flatip"
 	"github.com/ergochat/ergo/irc/history"
 	"github.com/ergochat/ergo/irc/modes"
+	"github.com/ergochat/ergo/irc/oauth2"
 	"github.com/ergochat/ergo/irc/sno"
 	"github.com/ergochat/ergo/irc/utils"
 )
@@ -119,12 +121,20 @@ type Client struct {
 
 type saslStatus struct {
 	mechanism string
-	value     string
+	value     ircutils.SASLBuffer
 	scramConv *scram.ServerConversation
+	oauthConv *oauth2.OAuthBearerServer
+}
+
+func (s *saslStatus) Initialize() {
+	s.value.Initialize(saslMaxResponseLength)
 }
 
 func (s *saslStatus) Clear() {
-	*s = saslStatus{}
+	s.mechanism = ""
+	s.value.Clear()
+	s.scramConv = nil
+	s.oauthConv = nil
 }
 
 // what stage the client is at w.r.t. the PASS command:
@@ -362,6 +372,7 @@ func (server *Server) RunClient(conn IRCConn) {
 		isTor:      wConn.Tor,
 		hideSTS:    wConn.Tor || wConn.HideSTS,
 	}
+	session.sasl.Initialize()
 	client.sessions = []*Session{session}
 
 	session.resetFakelag()

irc/config.go

@@ -38,6 +38,7 @@ import (
 	"github.com/ergochat/ergo/irc/logger"
 	"github.com/ergochat/ergo/irc/modes"
 	"github.com/ergochat/ergo/irc/mysql"
+	"github.com/ergochat/ergo/irc/oauth2"
 	"github.com/ergochat/ergo/irc/passwd"
 	"github.com/ergochat/ergo/irc/utils"
 )
@@ -331,7 +332,9 @@ type AccountConfig struct {
 	Multiclient MulticlientConfig
 	Bouncer     *MulticlientConfig // # handle old name for 'multiclient'
 	VHosts      VHostConfig
-	AuthScript  AuthScriptConfig `yaml:"auth-script"`
+	AuthScript  AuthScriptConfig          `yaml:"auth-script"`
+	OAuth2      oauth2.OAuth2BearerConfig `yaml:"oauth2"`
+	JWTAuth     jwt.JWTAuthConfig         `yaml:"jwt-auth"`
 }
 
 type ScriptConfig struct {
@@ -1391,15 +1394,44 @@ func LoadConfig(filename string) (config *Config, err error) {
 		config.Accounts.VHosts.validRegexp = defaultValidVhostRegex
 	}
 
-	saslCapValue := "PLAIN,EXTERNAL,SCRAM-SHA-256"
-	if !config.Accounts.AdvertiseSCRAM {
-		saslCapValue = "PLAIN,EXTERNAL"
-	}
-	config.Server.capValues[caps.SASL] = saslCapValue
-	if !config.Accounts.AuthenticationEnabled {
+	if config.Accounts.AuthenticationEnabled {
+		saslCapValues := []string{"PLAIN", "EXTERNAL"}
+		if config.Accounts.AdvertiseSCRAM {
+			saslCapValues = append(saslCapValues, "SCRAM-SHA-256")
+		}
+		if config.Accounts.OAuth2.Enabled {
+			saslCapValues = append(saslCapValues, "OAUTHBEARER")
+		}
+		config.Server.capValues[caps.SASL] = strings.Join(saslCapValues, ",")
+	} else {
 		config.Server.supportedCaps.Disable(caps.SASL)
 	}
 
+	if err := config.Accounts.OAuth2.Postprocess(); err != nil {
+		return nil, err
+	}
+
+	if err := config.Accounts.JWTAuth.Postprocess(); err != nil {
+		return nil, err
+	}
+
+	if config.Accounts.OAuth2.Enabled && config.Accounts.OAuth2.AuthScript && !config.Accounts.AuthScript.Enabled {
+		return nil, fmt.Errorf("oauth2 is enabled with auth-script, but no auth-script is enabled")
+	}
+
+	var bearerCapValues []string
+	if config.Accounts.OAuth2.Enabled {
+		bearerCapValues = append(bearerCapValues, "oauth2")
+	}
+	if config.Accounts.JWTAuth.Enabled {
+		bearerCapValues = append(bearerCapValues, "jwt")
+	}
+	if len(bearerCapValues) != 0 {
+		config.Server.capValues[caps.Bearer] = strings.Join(bearerCapValues, ",")
+	} else {
+		config.Server.supportedCaps.Disable(caps.Bearer)
+	}
+
 	if !config.Accounts.Registration.Enabled {
 		config.Server.supportedCaps.Disable(caps.AccountRegistration)
 	} else {

irc/errors.go

@@ -76,6 +76,7 @@ var (
 	errValidEmailRequired             = errors.New("A valid email address is required for account registration")
 	errInvalidAccountRename           = errors.New("Account renames can only change the casefolding of the account name")
 	errNameReserved                   = errors.New(`Name reserved due to a prior registration`)
+	errInvalidBearerTokenType         = errors.New("invalid bearer token type")
 )
 
 // String Errors

irc/handlers.go

@@ -8,7 +8,6 @@ package irc
 
 import (
 	"bytes"
-	"encoding/base64"
 	"fmt"
 	"net"
 	"os"
@@ -31,6 +30,7 @@ import (
 	"github.com/ergochat/ergo/irc/history"
 	"github.com/ergochat/ergo/irc/jwt"
 	"github.com/ergochat/ergo/irc/modes"
+	"github.com/ergochat/ergo/irc/oauth2"
 	"github.com/ergochat/ergo/irc/sno"
 	"github.com/ergochat/ergo/irc/utils"
 )
@@ -178,6 +178,10 @@ func acceptHandler(server *Server, client *Client, msg ircmsg.Message, rb *Respo
 	return false
 }
 
+const (
+	saslMaxResponseLength = 8192 // implementation-defined sanity check, long enough for bearer tokens
+)
+
 // AUTHENTICATE [<mechanism>|<data>|*]
 func authenticateHandler(server *Server, client *Client, msg ircmsg.Message, rb *ResponseBuffer) bool {
 	session := rb.session
@@ -201,7 +205,7 @@ func authenticateHandler(server *Server, client *Client, msg ircmsg.Message, rb
 		return false
 	}
 
-	// start new sasl session
+	// start new sasl session: parameter is the authentication mechanism
 	if session.sasl.mechanism == "" {
 		throttled, remainingTime := client.loginThrottle.Touch()
 		if throttled {
@@ -213,6 +217,16 @@ func authenticateHandler(server *Server, client *Client, msg ircmsg.Message, rb
 		mechanism := strings.ToUpper(msg.Params[0])
 		_, mechanismIsEnabled := EnabledSaslMechanisms[mechanism]
 
+		// The spec says: "The AUTHENTICATE command MUST be used before registration
+		// is complete and with the sasl capability enabled." Enforcing this universally
+		// would simplify the implementation somewhat, but we've never enforced it before
+		// and I don't want to break working clients that use PLAIN or EXTERNAL
+		// and violate this MUST (e.g. by sending CAP END too early).
+		if client.registered && !(mechanism == "PLAIN" || mechanism == "EXTERNAL") {
+			rb.Add(nil, server.name, ERR_SASLFAIL, details.nick, client.t("SASL is only allowed before connection registration"))
+			return false
+		}
+
 		if mechanismIsEnabled {
 			session.sasl.mechanism = mechanism
 			if !config.Server.Compatibility.SendUnprefixedSasl {
@@ -230,46 +244,28 @@ func authenticateHandler(server *Server, client *Client, msg ircmsg.Message, rb
 		return false
 	}
 
-	// continue existing sasl session
-	rawData := msg.Params[0]
-
-	// https://ircv3.net/specs/extensions/sasl-3.1:
-	// "The response is encoded in Base64 (RFC 4648), then split to 400-byte chunks,
-	// and each chunk is sent as a separate AUTHENTICATE command."
-	saslMaxArgLength := 400
-	if len(rawData) > saslMaxArgLength {
+	// continue existing sasl session: parameter is a message chunk
+	done, value, err := session.sasl.value.Add(msg.Params[0])
+	if err == nil {
+		if done {
+			// call actual handler
+			handler := EnabledSaslMechanisms[session.sasl.mechanism]
+			return handler(server, client, session, value, rb)
+		} else {
+			return false // wait for continuation line
+		}
+	}
+	// else: error handling
+	switch err {
+	case ircutils.ErrSASLTooLong:
 		rb.Add(nil, server.name, ERR_SASLTOOLONG, details.nick, client.t("SASL message too long"))
-		session.sasl.Clear()
-		return false
-	} else if len(rawData) == saslMaxArgLength {
-		// allow 4 'continuation' lines before rejecting for length
-		if len(session.sasl.value) >= saslMaxArgLength*4 {
-			rb.Add(nil, server.name, ERR_SASLFAIL, details.nick, client.t("SASL authentication failed: Passphrase too long"))
-			session.sasl.Clear()
-			return false
-		}
-		session.sasl.value += rawData
-		return false
+	case ircutils.ErrSASLLimitExceeded:
+		rb.Add(nil, server.name, ERR_SASLFAIL, details.nick, client.t("SASL authentication failed: Passphrase too long"))
+	default:
+		rb.Add(nil, server.name, ERR_SASLFAIL, details.nick, client.t("SASL authentication failed: Invalid b64 encoding"))
 	}
-	if rawData != "+" {
-		session.sasl.value += rawData
-	}
-
-	var data []byte
-	var err error
-	if session.sasl.value != "+" {
-		data, err = base64.StdEncoding.DecodeString(session.sasl.value)
-		session.sasl.value = ""
-		if err != nil {
-			rb.Add(nil, server.name, ERR_SASLFAIL, details.nick, client.t("SASL authentication failed: Invalid b64 encoding"))
-			session.sasl.Clear()
-			return false
-		}
-	}
-
-	// call actual handler
-	handler := EnabledSaslMechanisms[session.sasl.mechanism]
-	return handler(server, client, session, data, rb)
+	session.sasl.Clear()
+	return false
 }
 
 // AUTHENTICATE PLAIN
@@ -331,7 +327,7 @@ func authErrorToMessage(server *Server, err error) (msg string) {
 	}
 
 	switch err {
-	case errAccountDoesNotExist, errAccountUnverified, errAccountInvalidCredentials, errAuthzidAuthcidMismatch, errNickAccountMismatch, errAccountSuspended:
+	case errAccountDoesNotExist, errAccountUnverified, errAccountInvalidCredentials, errAuthzidAuthcidMismatch, errNickAccountMismatch, errAccountSuspended, oauth2.ErrInvalidToken:
 		return err.Error()
 	default:
 		// don't expose arbitrary error messages to the user
@@ -351,28 +347,18 @@ func authExternalHandler(server *Server, client *Client, session *Session, value
 
 	// EXTERNAL doesn't carry an authentication ID (this is determined from the
 	// certificate), but does carry an optional authorization ID.
-	var authzid string
+	authzid := string(value)
+	var deviceID string
 	var err error
-	if len(value) != 0 {
-		authzid, err = CasefoldName(string(value))
-		if err != nil {
-			err = errAuthzidAuthcidMismatch
-		}
+	// see #843: strip the device ID for the benefit of clients that don't
+	// distinguish user/ident from account name
+	if strudelIndex := strings.IndexByte(authzid, '@'); strudelIndex != -1 {
+		authzid, deviceID = authzid[:strudelIndex], authzid[strudelIndex+1:]
 	}
 
 	if err == nil {
-		// see #843: strip the device ID for the benefit of clients that don't
-		// distinguish user/ident from account name
-		if strudelIndex := strings.IndexByte(authzid, '@'); strudelIndex != -1 {
-			var deviceID string
-			authzid, deviceID = authzid[:strudelIndex], authzid[strudelIndex+1:]
-			if !client.registered {
-				rb.session.deviceID = deviceID
-			}
-		}
 		err = server.accounts.AuthenticateByCertificate(client, rb.session.certfp, rb.session.peerCerts, authzid)
 	}
-
 	if err != nil {
 		sendAuthErrorResponse(client, rb, err)
 		return false
@@ -381,6 +367,9 @@ func authExternalHandler(server *Server, client *Client, session *Session, value
 	}
 
 	sendSuccessfulAccountAuth(nil, client, rb, true)
+	if !client.registered && deviceID != "" {
+		rb.session.deviceID = deviceID
+	}
 	return false
 }
 
@@ -418,9 +407,8 @@ func authScramHandler(server *Server, client *Client, session *Session, value []
 			account, err := server.accounts.LoadAccount(authcid)
 			if err == nil {
 				server.accounts.Login(client, account)
-				if fixupNickEqualsAccount(client, rb, server.Config(), "") {
-					sendSuccessfulAccountAuth(nil, client, rb, true)
-				}
+				// fixupNickEqualsAccount is not needed for unregistered clients
+				sendSuccessfulAccountAuth(nil, client, rb, true)
 			} else {
 				server.logger.Error("internal", "SCRAM succeeded but couldn't load account", authcid, err.Error())
 				rb.Add(nil, server.name, ERR_SASLFAIL, client.nick, client.t("SASL authentication failed"))
@@ -433,7 +421,7 @@ func authScramHandler(server *Server, client *Client, session *Session, value []
 
 	response, err := session.sasl.scramConv.Step(string(value))
 	if err == nil {
-		rb.Add(nil, server.name, "AUTHENTICATE", base64.StdEncoding.EncodeToString([]byte(response)))
+		sendSASLChallenge(server, rb, []byte(response))
 	} else {
 		continueAuth = false
 		rb.Add(nil, server.name, ERR_SASLFAIL, client.Nick(), err.Error())
@@ -443,6 +431,58 @@ func authScramHandler(server *Server, client *Client, session *Session, value []
 	return false
 }
 
+// AUTHENTICATE OAUTHBEARER
+func authOauthBearerHandler(server *Server, client *Client, session *Session, value []byte, rb *ResponseBuffer) bool {
+	if !server.Config().Accounts.OAuth2.Enabled {
+		rb.Add(nil, server.name, ERR_SASLFAIL, client.Nick(), "SASL authentication failed: mechanism not enabled")
+		return false
+	}
+
+	if session.sasl.oauthConv == nil {
+		session.sasl.oauthConv = oauth2.NewOAuthBearerServer(
+			func(opts oauth2.OAuthBearerOptions) *oauth2.OAuthBearerError {
+				err := server.accounts.AuthenticateByOAuthBearer(client, opts)
+				switch err {
+				case nil:
+					return nil
+				case oauth2.ErrInvalidToken:
+					return &oauth2.OAuthBearerError{Status: "invalid_token", Schemes: "bearer"}
+				case errFeatureDisabled:
+					return &oauth2.OAuthBearerError{Status: "invalid_request", Schemes: "bearer"}
+				default:
+					// this is probably a misconfiguration or infrastructure error so we should log it
+					server.logger.Error("internal", "failed to validate OAUTHBEARER token", err.Error())
+					// tell the client it was their fault even though it probably wasn't:
+					return &oauth2.OAuthBearerError{Status: "invalid_request", Schemes: "bearer"}
+				}
+			},
+		)
+	}
+
+	challenge, done, err := session.sasl.oauthConv.Next(value)
+	if done {
+		if err == nil {
+			sendSuccessfulAccountAuth(nil, client, rb, true)
+		} else {
+			rb.Add(nil, server.name, ERR_SASLFAIL, client.Nick(), ircutils.SanitizeText(err.Error(), 350))
+		}
+		session.sasl.Clear()
+	} else {
+		// ignore `err`, we need to relay the challenge (which may contain a JSON-encoded error)
+		// to the client
+		sendSASLChallenge(server, rb, challenge)
+	}
+	return false
+}
+
+// helper to b64 a sasl response and chunk it into 400-byte lines
+// as per https://ircv3.net/specs/extensions/sasl-3.1
+func sendSASLChallenge(server *Server, rb *ResponseBuffer, challenge []byte) {
+	for _, chunk := range ircutils.EncodeSASLResponse(challenge) {
+		rb.Add(nil, server.name, "AUTHENTICATE", chunk)
+	}
+}
+
 // AWAY [<message>]
 func awayHandler(server *Server, client *Client, msg ircmsg.Message, rb *ResponseBuffer) bool {
 	// #1996: `AWAY :` is treated the same as `AWAY`

irc/jwt/bearer.go

@@ -0,0 +1,157 @@
+// Copyright (c) 2024 Shivaram Lingamneni <slingamn@cs.stanford.edu>
+// released under the MIT license
+
+package jwt
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"strings"
+
+	jwt "github.com/golang-jwt/jwt/v5"
+)
+
+var (
+	ErrAuthDisabled        = fmt.Errorf("JWT authentication is disabled")
+	ErrNoValidAccountClaim = fmt.Errorf("JWT token did not contain an acceptable account name claim")
+)
+
+// JWTAuthConfig is the config for Ergo to accept JWTs via draft/bearer
+type JWTAuthConfig struct {
+	Enabled    bool                 `yaml:"enabled"`
+	Autocreate bool                 `yaml:"autocreate"`
+	Tokens     []JWTAuthTokenConfig `yaml:"tokens"`
+}
+
+type JWTAuthTokenConfig struct {
+	Algorithm     string `yaml:"algorithm"`
+	KeyString     string `yaml:"key"`
+	KeyFile       string `yaml:"key-file"`
+	key           any
+	parser        *jwt.Parser
+	AccountClaims []string `yaml:"account-claims"`
+	StripDomain   string   `yaml:"strip-domain"`
+}
+
+func (j *JWTAuthConfig) Postprocess() error {
+	if !j.Enabled {
+		return nil
+	}
+
+	if len(j.Tokens) == 0 {
+		return fmt.Errorf("JWT authentication enabled, but no valid tokens defined")
+	}
+
+	for i := range j.Tokens {
+		if err := j.Tokens[i].Postprocess(); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (j *JWTAuthTokenConfig) Postprocess() error {
+	keyBytes, err := j.keyBytes()
+	if err != nil {
+		return err
+	}
+
+	j.Algorithm = strings.ToLower(j.Algorithm)
+
+	var methods []string
+	switch j.Algorithm {
+	case "hmac":
+		j.key = keyBytes
+		methods = []string{"HS256", "HS384", "HS512"}
+	case "rsa":
+		rsaKey, err := jwt.ParseRSAPublicKeyFromPEM(keyBytes)
+		if err != nil {
+			return err
+		}
+		j.key = rsaKey
+		methods = []string{"RS256", "RS384", "RS512"}
+	case "eddsa":
+		eddsaKey, err := jwt.ParseEdPublicKeyFromPEM(keyBytes)
+		if err != nil {
+			return err
+		}
+		j.key = eddsaKey
+		methods = []string{"EdDSA"}
+	default:
+		return fmt.Errorf("invalid jwt algorithm: %s", j.Algorithm)
+	}
+	j.parser = jwt.NewParser(jwt.WithValidMethods(methods))
+
+	if len(j.AccountClaims) == 0 {
+		return fmt.Errorf("JWT auth enabled, but no account-claims specified")
+	}
+
+	j.StripDomain = strings.ToLower(j.StripDomain)
+	return nil
+}
+
+func (j *JWTAuthConfig) Validate(t string) (accountName string, err error) {
+	if !j.Enabled || len(j.Tokens) == 0 {
+		return "", ErrAuthDisabled
+	}
+
+	for i := range j.Tokens {
+		accountName, err = j.Tokens[i].Validate(t)
+		if err == nil {
+			return
+		}
+	}
+	return
+}
+
+func (j *JWTAuthTokenConfig) keyBytes() (result []byte, err error) {
+	if j.KeyFile != "" {
+		o, err := os.Open(j.KeyFile)
+		if err != nil {
+			return nil, err
+		}
+		return io.ReadAll(o)
+	}
+	if j.KeyString != "" {
+		return []byte(j.KeyString), nil
+	}
+	return nil, fmt.Errorf("JWT auth enabled, but no JWT key specified")
+}
+
+// implements jwt.Keyfunc
+func (j *JWTAuthTokenConfig) keyFunc(_ *jwt.Token) (interface{}, error) {
+	return j.key, nil
+}
+
+func (j *JWTAuthTokenConfig) Validate(t string) (accountName string, err error) {
+	token, err := j.parser.Parse(t, j.keyFunc)
+	if err != nil {
+		return "", err
+	}
+
+	claims, ok := token.Claims.(jwt.MapClaims)
+	if !ok {
+		// impossible with Parse (as opposed to ParseWithClaims)
+		return "", fmt.Errorf("unexpected type from parsed token claims: %T", claims)
+	}
+
+	for _, c := range j.AccountClaims {
+		if v, ok := claims[c]; ok {
+			if vstr, ok := v.(string); ok {
+				// validate and strip email addresses:
+				if idx := strings.IndexByte(vstr, '@'); idx != -1 {
+					suffix := vstr[idx+1:]
+					vstr = vstr[:idx]
+					if strings.ToLower(suffix) != j.StripDomain {
+						continue
+					}
+				}
+				return vstr, nil // success
+			}
+		}
+	}
+
+	return "", ErrNoValidAccountClaim
+}

irc/jwt/bearer_test.go

@@ -0,0 +1,143 @@
+package jwt
+
+import (
+	"testing"
+
+	jwt "github.com/golang-jwt/jwt/v5"
+)
+
+const (
+	rsaTestPubKey = `-----BEGIN PUBLIC KEY-----
+MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAwhcCcXrfR/GmoPKxBi0H
+cUl2pUl4acq2m3abFtMMoYTydJdEhgYWfsXuragyEIVkJU1ZnrgedW0QJUcANRGO
+hP/B+MjBevDNsRXQECfhyjfzhz6KWZb4i7C2oImJuAjq/F4qGLdEGQDBpAzof8qv
+9Zt5iN3GXY/EQtQVMFyR/7BPcbPLbHlOtzZ6tVEioXuUxQoai7x3Kc0jIcPWuyGa
+Q04IvsgdaWO6oH4fhPfyVsmX37rYUn79zcqPHS4ieWM1KN9qc7W+/UJIeiwAStpJ
+8gv+OSMrijRZGgQGCeOO5U59GGJC4mqUczB+JFvrlAIv0rggNpl+qalngosNxukB
+uQIDAQAB
+-----END PUBLIC KEY-----`
+
+	rsaTestPrivKey = `-----BEGIN PRIVATE KEY-----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+-----END PRIVATE KEY-----`
+)
+
+func TestJWTBearerAuth(t *testing.T) {
+	j := JWTAuthConfig{
+		Enabled: true,
+		Tokens: []JWTAuthTokenConfig{
+			{
+				Algorithm:     "rsa",
+				KeyString:     rsaTestPubKey,
+				AccountClaims: []string{"preferred_username", "email"},
+				StripDomain:   "example.com",
+			},
+		},
+	}
+
+	if err := j.Postprocess(); err != nil {
+		t.Fatal(err)
+	}
+
+	// fixed test vector signed with the RSA privkey:
+	token := "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9.eyJwcmVmZXJyZWRfdXNlcm5hbWUiOiJzbGluZ2FtbiJ9.caPZw2Dl4KZN-SErD5-WZB_lPPveHXaMCoUHxNebb94G9w3VaWDIRdngVU99JKx5nE_yRtpewkHHvXsQnNA_M63GBXGK7afXB8e-kV33QF3v9pXALMP5SzRwMgokyxas0RgHu4e4L0d7dn9o_nkdXp34GX3Pn1MVkUGBH6GdlbOdDHrs04pPQ0Qj-O2U0AIpnZq-X_GQs9ECJo4TlPKWR7Jlq5l9bS0dBnohea4FuqJr232je-dlRVkbCa7nrnFmsIsezsgA3Jb_j9Zu_iv460t_d2eaytbVp9P-DOVfzUfkBsKs-81URQEnTjW6ut445AJz2pxjX92X0GdmORpAkQ"
+	accountName, err := j.Validate(token)
+	if err != nil {
+		t.Errorf("could not validate valid token: %v", err)
+	}
+	if accountName != "slingamn" {
+		t.Errorf("incorrect account name for token: `%s`", accountName)
+	}
+
+	// programmatically sign a new token, validate it
+	privKey, err := jwt.ParseRSAPrivateKeyFromPEM([]byte(rsaTestPrivKey))
+	if err != nil {
+		t.Fatal(err)
+	}
+	jTok := jwt.NewWithClaims(jwt.SigningMethodRS256, jwt.MapClaims(map[string]any{"preferred_username": "slingamn"}))
+	token, err = jTok.SignedString(privKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+	accountName, err = j.Validate(token)
+	if err != nil {
+		t.Errorf("could not validate valid token: %v", err)
+	}
+	if accountName != "slingamn" {
+		t.Errorf("incorrect account name for token: `%s`", accountName)
+	}
+
+	// test expiration
+	jTok = jwt.NewWithClaims(jwt.SigningMethodRS256, jwt.MapClaims(map[string]any{"preferred_username": "slingamn", "exp": 1675740865}))
+	token, err = jTok.SignedString(privKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+	accountName, err = j.Validate(token)
+	if err == nil {
+		t.Errorf("validated expired token")
+	}
+
+	// test for the infamous algorithm confusion bug
+	jTok = jwt.NewWithClaims(jwt.SigningMethodHS256, jwt.MapClaims(map[string]any{"preferred_username": "slingamn"}))
+	token, err = jTok.SignedString([]byte(rsaTestPubKey))
+	if err != nil {
+		t.Fatal(err)
+	}
+	accountName, err = j.Validate(token)
+	if err == nil {
+		t.Errorf("validated HS256 token despite RSA being required")
+	}
+
+	// test no valid claims
+	jTok = jwt.NewWithClaims(jwt.SigningMethodRS256, jwt.MapClaims(map[string]any{"sub": "slingamn"}))
+	token, err = jTok.SignedString(privKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	accountName, err = j.Validate(token)
+	if err != ErrNoValidAccountClaim {
+		t.Errorf("expected ErrNoValidAccountClaim, got: %v", err)
+	}
+
+	// test email addresses
+	jTok = jwt.NewWithClaims(jwt.SigningMethodRS256, jwt.MapClaims(map[string]any{"email": "Slingamn@example.com"}))
+	token, err = jTok.SignedString(privKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	accountName, err = j.Validate(token)
+	if err != nil {
+		t.Errorf("could not validate valid token: %v", err)
+	}
+	if accountName != "Slingamn" {
+		t.Errorf("incorrect account name for token: `%s`", accountName)
+	}
+}

irc/jwt/extjwt.go

@@ -6,18 +6,15 @@ package jwt
 
 import (
 	"crypto/rsa"
-	"crypto/x509"
-	"encoding/pem"
 	"errors"
-	"fmt"
 	"os"
 	"time"
 
-	"github.com/golang-jwt/jwt"
+	jwt "github.com/golang-jwt/jwt/v5"
 )
 
 var (
-	ErrNoKeys = errors.New("No signing keys are enabled")
+	ErrNoKeys = errors.New("No EXTJWT signing keys are enabled")
 )
 
 type MapClaims jwt.MapClaims
@@ -38,22 +35,10 @@ func (t *JwtServiceConfig) Postprocess() (err error) {
 		if err != nil {
 			return err
 		}
-		d, _ := pem.Decode(keyBytes)
+		t.rsaPrivateKey, err = jwt.ParseRSAPrivateKeyFromPEM(keyBytes)
 		if err != nil {
 			return err
 		}
-		t.rsaPrivateKey, err = x509.ParsePKCS1PrivateKey(d.Bytes)
-		if err != nil {
-			privateKey, err := x509.ParsePKCS8PrivateKey(d.Bytes)
-			if err != nil {
-				return err
-			}
-			if rsaPrivateKey, ok := privateKey.(*rsa.PrivateKey); ok {
-				t.rsaPrivateKey = rsaPrivateKey
-			} else {
-				return fmt.Errorf("Non-RSA key type for extjwt: %T", privateKey)
-			}
-		}
 	}
 	return nil
 }

irc/oauth2/oauth2.go

@@ -0,0 +1,108 @@
+// Copyright 2022-2023 Simon Ser <contact@emersion.fr>
+// Derived from https://git.sr.ht/~emersion/soju/tree/36d6cb19a4f90d217d55afb0b15318321baaad09/item/auth/oauth2.go
+// Originally released under the AGPLv3, relicensed to the Ergo project under the MIT license
+// Modifications copyright 2024 Shivaram Lingamneni <slingamn@cs.stanford.edu>
+// Released under the MIT license
+
+package oauth2
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+)
+
+var (
+	ErrAuthDisabled = fmt.Errorf("OAuth 2.0 authentication is disabled")
+
+	// all cases where the infrastructure is working correctly, but we determined
+	// that the user supplied an invalid token
+	ErrInvalidToken = fmt.Errorf("OAuth 2.0 bearer token invalid")
+)
+
+type OAuth2BearerConfig struct {
+	Enabled              bool          `yaml:"enabled"`
+	Autocreate           bool          `yaml:"autocreate"`
+	AuthScript           bool          `yaml:"auth-script"`
+	IntrospectionURL     string        `yaml:"introspection-url"`
+	IntrospectionTimeout time.Duration `yaml:"introspection-timeout"`
+	// omit for `none`, required for `client_secret_basic`
+	ClientID     string `yaml:"client-id"`
+	ClientSecret string `yaml:"client-secret"`
+}
+
+func (o *OAuth2BearerConfig) Postprocess() error {
+	if !o.Enabled {
+		return nil
+	}
+
+	if o.IntrospectionTimeout == 0 {
+		return fmt.Errorf("a nonzero oauthbearer introspection timeout is required (try 10s)")
+	}
+
+	if _, err := url.Parse(o.IntrospectionURL); err != nil {
+		return fmt.Errorf("invalid introspection-url: %w", err)
+	}
+
+	return nil
+}
+
+func (o *OAuth2BearerConfig) Introspect(ctx context.Context, token string) (username string, err error) {
+	if !o.Enabled {
+		return "", ErrAuthDisabled
+	}
+
+	ctx, cancel := context.WithTimeout(ctx, o.IntrospectionTimeout)
+	defer cancel()
+
+	reqValues := make(url.Values)
+	reqValues.Set("token", token)
+
+	reqBody := strings.NewReader(reqValues.Encode())
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, o.IntrospectionURL, reqBody)
+	if err != nil {
+		return "", fmt.Errorf("failed to create OAuth 2.0 introspection request: %w", err)
+	}
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	req.Header.Set("Accept", "application/json")
+
+	if o.ClientID != "" {
+		req.SetBasicAuth(url.QueryEscape(o.ClientID), url.QueryEscape(o.ClientSecret))
+	}
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return "", fmt.Errorf("failed to send OAuth 2.0 introspection request: %v", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return "", fmt.Errorf("OAuth 2.0 introspection error: %v", resp.Status)
+	}
+
+	var data oauth2Introspection
+	if err := json.NewDecoder(resp.Body).Decode(&data); err != nil {
+		return "", fmt.Errorf("failed to decode OAuth 2.0 introspection response: %v", err)
+	}
+
+	if !data.Active {
+		return "", ErrInvalidToken
+	}
+	if data.Username == "" {
+		// We really need the username here, otherwise an OAuth 2.0 user can
+		// impersonate any other user.
+		return "", fmt.Errorf("missing username in OAuth 2.0 introspection response")
+	}
+
+	return data.Username, nil
+}
+
+type oauth2Introspection struct {
+	Active   bool   `json:"active"`
+	Username string `json:"username"`
+}

irc/oauth2/sasl.go

@@ -0,0 +1,172 @@
+package oauth2
+
+/*
+https://github.com/emersion/go-sasl/blob/e73c9f7bad438a9bf3f5b28e661b74d752ecafdd/oauthbearer.go
+
+Copyright 2019-2022 Simon Ser, Frode Aannevik, Max Mazurov
+Released under the MIT license
+*/
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+var (
+	ErrUnexpectedClientResponse = errors.New("unexpected client response")
+)
+
+// The OAUTHBEARER mechanism name.
+const OAuthBearer = "OAUTHBEARER"
+
+type OAuthBearerError struct {
+	Status  string `json:"status"`
+	Schemes string `json:"schemes"`
+	Scope   string `json:"scope"`
+}
+
+type OAuthBearerOptions struct {
+	Username string `json:"username,omitempty"`
+	Token    string `json:"token,omitempty"`
+	Host     string `json:"host,omitempty"`
+	Port     int    `json:"port,omitempty"`
+}
+
+func (err *OAuthBearerError) Error() string {
+	return fmt.Sprintf("OAUTHBEARER authentication error (%v)", err.Status)
+}
+
+type OAuthBearerAuthenticator func(opts OAuthBearerOptions) *OAuthBearerError
+
+type OAuthBearerServer struct {
+	done         bool
+	failErr      error
+	authenticate OAuthBearerAuthenticator
+}
+
+func (a *OAuthBearerServer) fail(descr string) ([]byte, bool, error) {
+	blob, err := json.Marshal(OAuthBearerError{
+		Status:  "invalid_request",
+		Schemes: "bearer",
+	})
+	if err != nil {
+		panic(err) // wtf
+	}
+	a.failErr = errors.New(descr)
+	return blob, false, nil
+}
+
+func (a *OAuthBearerServer) Next(response []byte) (challenge []byte, done bool, err error) {
+	// Per RFC, we cannot just send an error, we need to return JSON-structured
+	// value as a challenge and then after getting dummy response from the
+	// client stop the exchange.
+	if a.failErr != nil {
+		// Server libraries (go-smtp, go-imap) will not call Next on
+		// protocol-specific SASL cancel response ('*'). However, GS2 (and
+		// indirectly OAUTHBEARER) defines a protocol-independent way to do so
+		// using 0x01.
+		if len(response) != 1 && response[0] != 0x01 {
+			return nil, true, errors.New("unexpected response")
+		}
+		return nil, true, a.failErr
+	}
+
+	if a.done {
+		err = ErrUnexpectedClientResponse
+		return
+	}
+
+	// Generate empty challenge.
+	if response == nil {
+		return []byte{}, false, nil
+	}
+
+	a.done = true
+
+	// Cut n,a=username,\x01host=...\x01auth=...
+	// into
+	//   n
+	//   a=username
+	//   \x01host=...\x01auth=...\x01\x01
+	parts := bytes.SplitN(response, []byte{','}, 3)
+	if len(parts) != 3 {
+		return a.fail("Invalid response")
+	}
+	flag := parts[0]
+	authzid := parts[1]
+	if !bytes.Equal(flag, []byte{'n'}) {
+		return a.fail("Invalid response, missing 'n' in gs2-cb-flag")
+	}
+	opts := OAuthBearerOptions{}
+	if len(authzid) > 0 {
+		if !bytes.HasPrefix(authzid, []byte("a=")) {
+			return a.fail("Invalid response, missing 'a=' in gs2-authzid")
+		}
+		opts.Username = string(bytes.TrimPrefix(authzid, []byte("a=")))
+	}
+
+	// Cut \x01host=...\x01auth=...\x01\x01
+	// into
+	//   *empty*
+	//   host=...
+	//   auth=...
+	//   *empty*
+	//
+	// Note that this code does not do a lot of checks to make sure the input
+	// follows the exact format specified by RFC.
+	params := bytes.Split(parts[2], []byte{0x01})
+	for _, p := range params {
+		// Skip empty fields (one at start and end).
+		if len(p) == 0 {
+			continue
+		}
+
+		pParts := bytes.SplitN(p, []byte{'='}, 2)
+		if len(pParts) != 2 {
+			return a.fail("Invalid response, missing '='")
+		}
+
+		switch string(pParts[0]) {
+		case "host":
+			opts.Host = string(pParts[1])
+		case "port":
+			port, err := strconv.ParseUint(string(pParts[1]), 10, 16)
+			if err != nil {
+				return a.fail("Invalid response, malformed 'port' value")
+			}
+			opts.Port = int(port)
+		case "auth":
+			const prefix = "bearer "
+			strValue := string(pParts[1])
+			// Token type is case-insensitive.
+			if !strings.HasPrefix(strings.ToLower(strValue), prefix) {
+				return a.fail("Unsupported token type")
+			}
+			opts.Token = strValue[len(prefix):]
+		default:
+			return a.fail("Invalid response, unknown parameter: " + string(pParts[0]))
+		}
+	}
+
+	authzErr := a.authenticate(opts)
+	if authzErr != nil {
+		blob, err := json.Marshal(authzErr)
+		if err != nil {
+			panic(err) // wtf
+		}
+		a.failErr = authzErr
+		return blob, false, nil
+	}
+
+	return nil, true, nil
+}
+
+func NewOAuthBearerServer(auth OAuthBearerAuthenticator) *OAuthBearerServer {
+	return &OAuthBearerServer{
+		authenticate: auth,
+	}
+}

traditional.yaml

@@ -559,6 +559,40 @@ accounts:
         # how many scripts are allowed to run at once? 0 for no limit:
         max-concurrency: 64
 
+    # support for login via OAuth2 bearer tokens
+    oauth2:
+        enabled: false
+        # should we automatically create users on presentation of a valid token?
+        autocreate: true
+        # enable this to use auth-script for validation:
+        auth-script: false
+        introspection-url: "https://example.com/api/oidc/introspection"
+        introspection-timeout: 10s
+        # omit for auth method `none`; required for auth method `client_secret_basic`:
+        client-id: "ergo"
+        client-secret: "4TA0I7mJ3fUUcW05KJiODg"
+
+    # support for login via JWT bearer tokens
+    jwt-auth:
+        enabled: false
+        # should we automatically create users on presentation of a valid token?
+        autocreate: true
+        # any of these token definitions can be accepted, allowing for key rotation
+        tokens:
+            -
+                algorithm: "hmac" # either 'hmac', 'rsa', or 'eddsa' (ed25519)
+                # hmac takes a symmetric key, rsa and eddsa take PEM-encoded public keys;
+                # either way, the key can be specified either as a YAML string:
+                key: "nANiZ1De4v6WnltCHN2H7Q"
+                # or as a path to the file containing the key:
+                #key-file: "jwt_pubkey.pem"
+                # list of JWT claim names to search for the user's account name (make sure the format
+                # is what you expect, especially if using "sub"):
+                account-claims: ["preferred_username"]
+                # if a claim is formatted as an email address, require it to have the following domain,
+                # and then strip off the domain and use the local-part as the account name:
+                #strip-domain: "example.com"
+
 # channel options
 channels:
     # modes that are set when new channels are created

vendor/github.com/ergochat/irc-go/ircutils/sasl.go

@@ -0,0 +1,105 @@
+package ircutils
+
+import (
+	"encoding/base64"
+	"errors"
+	"strings"
+)
+
+var (
+	ErrSASLLimitExceeded = errors.New("SASL total response size exceeded configured limit")
+	ErrSASLTooLong       = errors.New("SASL response chunk exceeded 400-byte limit")
+)
+
+// EncodeSASLResponse encodes a raw SASL response as parameters to successive
+// AUTHENTICATE commands, as described in the IRCv3 SASL specification.
+func EncodeSASLResponse(raw []byte) (result []string) {
+	// https://ircv3.net/specs/extensions/sasl-3.1#the-authenticate-command
+	// "The response is encoded in Base64 (RFC 4648), then split to 400-byte chunks,
+	// and each chunk is sent as a separate AUTHENTICATE command. Empty (zero-length)
+	// responses are sent as AUTHENTICATE +. If the last chunk was exactly 400 bytes
+	// long, it must also be followed by AUTHENTICATE + to signal end of response."
+
+	if len(raw) == 0 {
+		return []string{"+"}
+	}
+
+	response := base64.StdEncoding.EncodeToString(raw)
+	lastLen := 0
+	for len(response) > 0 {
+		// TODO once we require go 1.21, this can be: lastLen = min(len(response), 400)
+		lastLen = len(response)
+		if lastLen > 400 {
+			lastLen = 400
+		}
+		result = append(result, response[:lastLen])
+		response = response[lastLen:]
+	}
+
+	if lastLen == 400 {
+		result = append(result, "+")
+	}
+
+	return result
+}
+
+// SASLBuffer handles buffering and decoding SASL responses sent as parameters
+// to AUTHENTICATE commands, as described in the IRCv3 SASL specification.
+// Do not copy a SASLBuffer after first use.
+type SASLBuffer struct {
+	maxLength int
+	buffer    strings.Builder
+}
+
+// NewSASLBuffer returns a new SASLBuffer. maxLength is the maximum amount of
+// base64'ed data to buffer (0 for no limit).
+func NewSASLBuffer(maxLength int) *SASLBuffer {
+	result := new(SASLBuffer)
+	result.Initialize(maxLength)
+	return result
+}
+
+// Initialize initializes a SASLBuffer in place.
+func (b *SASLBuffer) Initialize(maxLength int) {
+	b.maxLength = maxLength
+}
+
+// Add processes an additional SASL response chunk sent via AUTHENTICATE.
+// If the response is complete, it resets the buffer and returns the decoded
+// response along with any decoding or protocol errors detected.
+func (b *SASLBuffer) Add(value string) (done bool, output []byte, err error) {
+	if value == "+" {
+		output, err = b.getAndReset()
+		return true, output, err
+	}
+
+	if len(value) > 400 {
+		b.buffer.Reset()
+		return true, nil, ErrSASLTooLong
+	}
+
+	if b.maxLength != 0 && (b.buffer.Len()+len(value)) > b.maxLength {
+		b.buffer.Reset()
+		return true, nil, ErrSASLLimitExceeded
+	}
+
+	b.buffer.WriteString(value)
+	if len(value) < 400 {
+		output, err = b.getAndReset()
+		return true, output, err
+	} else {
+		// 400 bytes, wait for continuation line or +
+		return false, nil, nil
+	}
+}
+
+// Clear resets the buffer state.
+func (b *SASLBuffer) Clear() {
+	b.buffer.Reset()
+}
+
+func (b *SASLBuffer) getAndReset() (output []byte, err error) {
+	output, err = base64.StdEncoding.DecodeString(b.buffer.String())
+	b.buffer.Reset()
+	return
+}

vendor/github.com/golang-jwt/jwt/MIGRATION_GUIDE.md

@@ -1,22 +0,0 @@
-## Migration Guide (v3.2.1)
-
-Starting from [v3.2.1](https://github.com/golang-jwt/jwt/releases/tag/v3.2.1]), the import path has changed from `github.com/dgrijalva/jwt-go` to `github.com/golang-jwt/jwt`. Future releases will be using the `github.com/golang-jwt/jwt` import path and continue the existing versioning scheme of `v3.x.x+incompatible`. Backwards-compatible patches and fixes will be done on the `v3` release branch, where as new build-breaking features will be developed in a `v4` release, possibly including a SIV-style import path.
-
-### go.mod replacement
-
-In a first step, the easiest way is to use `go mod edit` to issue a replacement.
-
-```
-go mod edit -replace github.com/dgrijalva/jwt-go=github.com/golang-jwt/jwt@v3.2.1+incompatible
-go mod tidy
-```
-
-This will still keep the old import path in your code but replace it with the new package and also introduce a new indirect dependency to `github.com/golang-jwt/jwt`. Try to compile your project; it should still work.
-
-### Cleanup
-
-If your code still consistently builds, you can replace all occurences of `github.com/dgrijalva/jwt-go` with `github.com/golang-jwt/jwt`, either manually or by using tools such as `sed`. Finally, the `replace` directive in the `go.mod` file can be removed.
-
-## Older releases (before v3.2.0)
-
-The original migration guide for older releases can be found at https://github.com/dgrijalva/jwt-go/blob/master/MIGRATION_GUIDE.md.

vendor/github.com/golang-jwt/jwt/README.md

@@ -1,113 +0,0 @@
-# jwt-go
-
-[![build](https://github.com/golang-jwt/jwt/actions/workflows/build.yml/badge.svg)](https://github.com/golang-jwt/jwt/actions/workflows/build.yml)
-[![Go Reference](https://pkg.go.dev/badge/github.com/golang-jwt/jwt.svg)](https://pkg.go.dev/github.com/golang-jwt/jwt)
-
-A [go](http://www.golang.org) (or 'golang' for search engine friendliness) implementation of [JSON Web Tokens](https://datatracker.ietf.org/doc/html/rfc7519).
-
-**IMPORT PATH CHANGE:** Starting from [v3.2.1](https://github.com/golang-jwt/jwt/releases/tag/v3.2.1), the import path has changed from `github.com/dgrijalva/jwt-go` to `github.com/golang-jwt/jwt`. After the original author of the library suggested migrating the maintenance of `jwt-go`, a dedicated team of open source maintainers decided to clone the existing library into this repository. See [dgrijalva/jwt-go#462](https://github.com/dgrijalva/jwt-go/issues/462) for a detailed discussion on this topic.
-
-Future releases will be using the `github.com/golang-jwt/jwt` import path and continue the existing versioning scheme of `v3.x.x+incompatible`. Backwards-compatible patches and fixes will be done on the `v3` release branch, where as new build-breaking features will be developed in a `v4` release, possibly including a SIV-style import path.
-
-**SECURITY NOTICE:** Some older versions of Go have a security issue in the crypto/elliptic. Recommendation is to upgrade to at least 1.15 See issue [dgrijalva/jwt-go#216](https://github.com/dgrijalva/jwt-go/issues/216) for more detail.
-
-**SECURITY NOTICE:** It's important that you [validate the `alg` presented is what you expect](https://auth0.com/blog/critical-vulnerabilities-in-json-web-token-libraries/). This library attempts to make it easy to do the right thing by requiring key types match the expected alg, but you should take the extra step to verify it in your usage.  See the examples provided.
-
-### Supported Go versions
-
-Our support of Go versions is aligned with Go's [version release policy](https://golang.org/doc/devel/release#policy).
-So we will support a major version of Go until there are two newer major releases.
-We no longer support building jwt-go with unsupported Go versions, as these contain security vulnerabilities
-which will not be fixed.
-
-## What the heck is a JWT?
-
-JWT.io has [a great introduction](https://jwt.io/introduction) to JSON Web Tokens.
-
-In short, it's a signed JSON object that does something useful (for example, authentication).  It's commonly used for `Bearer` tokens in Oauth 2.  A token is made of three parts, separated by `.`'s.  The first two parts are JSON objects, that have been [base64url](https://datatracker.ietf.org/doc/html/rfc4648) encoded.  The last part is the signature, encoded the same way.
-
-The first part is called the header.  It contains the necessary information for verifying the last part, the signature.  For example, which encryption method was used for signing and what key was used.
-
-The part in the middle is the interesting bit.  It's called the Claims and contains the actual stuff you care about.  Refer to [RFC 7519](https://datatracker.ietf.org/doc/html/rfc7519) for information about reserved keys and the proper way to add your own.
-
-## What's in the box?
-
-This library supports the parsing and verification as well as the generation and signing of JWTs.  Current supported signing algorithms are HMAC SHA, RSA, RSA-PSS, and ECDSA, though hooks are present for adding your own.
-
-## Examples
-
-See [the project documentation](https://pkg.go.dev/github.com/golang-jwt/jwt) for examples of usage:
-
-* [Simple example of parsing and validating a token](https://pkg.go.dev/github.com/golang-jwt/jwt#example-Parse-Hmac)
-* [Simple example of building and signing a token](https://pkg.go.dev/github.com/golang-jwt/jwt#example-New-Hmac)
-* [Directory of Examples](https://pkg.go.dev/github.com/golang-jwt/jwt#pkg-examples)
-
-## Extensions
-
-This library publishes all the necessary components for adding your own signing methods.  Simply implement the `SigningMethod` interface and register a factory method using `RegisterSigningMethod`.  
-
-Here's an example of an extension that integrates with multiple Google Cloud Platform signing tools (AppEngine, IAM API, Cloud KMS): https://github.com/someone1/gcp-jwt-go
-
-## Compliance
-
-This library was last reviewed to comply with [RTF 7519](https://datatracker.ietf.org/doc/html/rfc7519) dated May 2015 with a few notable differences:
-
-* In order to protect against accidental use of [Unsecured JWTs](https://datatracker.ietf.org/doc/html/rfc7519#section-6), tokens using `alg=none` will only be accepted if the constant `jwt.UnsafeAllowNoneSignatureType` is provided as the key.
-
-## Project Status & Versioning
-
-This library is considered production ready.  Feedback and feature requests are appreciated.  The API should be considered stable.  There should be very few backwards-incompatible changes outside of major version updates (and only with good reason).
-
-This project uses [Semantic Versioning 2.0.0](http://semver.org).  Accepted pull requests will land on `main`.  Periodically, versions will be tagged from `main`.  You can find all the releases on [the project releases page](https://github.com/golang-jwt/jwt/releases).
-
-While we try to make it obvious when we make breaking changes, there isn't a great mechanism for pushing announcements out to users.  You may want to use this alternative package include: `gopkg.in/golang-jwt/jwt.v3`.  It will do the right thing WRT semantic versioning.
-
-**BREAKING CHANGES:*** 
-* Version 3.0.0 includes _a lot_ of changes from the 2.x line, including a few that break the API.  We've tried to break as few things as possible, so there should just be a few type signature changes.  A full list of breaking changes is available in `VERSION_HISTORY.md`.  See `MIGRATION_GUIDE.md` for more information on updating your code.
-
-## Usage Tips
-
-### Signing vs Encryption
-
-A token is simply a JSON object that is signed by its author. this tells you exactly two things about the data:
-
-* The author of the token was in the possession of the signing secret
-* The data has not been modified since it was signed
-
-It's important to know that JWT does not provide encryption, which means anyone who has access to the token can read its contents. If you need to protect (encrypt) the data, there is a companion spec, `JWE`, that provides this functionality. JWE is currently outside the scope of this library.
-
-### Choosing a Signing Method
-
-There are several signing methods available, and you should probably take the time to learn about the various options before choosing one.  The principal design decision is most likely going to be symmetric vs asymmetric.
-
-Symmetric signing methods, such as HSA, use only a single secret. This is probably the simplest signing method to use since any `[]byte` can be used as a valid secret. They are also slightly computationally faster to use, though this rarely is enough to matter. Symmetric signing methods work the best when both producers and consumers of tokens are trusted, or even the same system. Since the same secret is used to both sign and validate tokens, you can't easily distribute the key for validation.
-
-Asymmetric signing methods, such as RSA, use different keys for signing and verifying tokens. This makes it possible to produce tokens with a private key, and allow any consumer to access the public key for verification.
-
-### Signing Methods and Key Types
-
-Each signing method expects a different object type for its signing keys. See the package documentation for details. Here are the most common ones:
-
-* The [HMAC signing method](https://pkg.go.dev/github.com/golang-jwt/jwt#SigningMethodHMAC) (`HS256`,`HS384`,`HS512`) expect `[]byte` values for signing and validation
-* The [RSA signing method](https://pkg.go.dev/github.com/golang-jwt/jwt#SigningMethodRSA) (`RS256`,`RS384`,`RS512`) expect `*rsa.PrivateKey` for signing and `*rsa.PublicKey` for validation
-* The [ECDSA signing method](https://pkg.go.dev/github.com/golang-jwt/jwt#SigningMethodECDSA) (`ES256`,`ES384`,`ES512`) expect `*ecdsa.PrivateKey` for signing and `*ecdsa.PublicKey` for validation
-
-### JWT and OAuth
-
-It's worth mentioning that OAuth and JWT are not the same thing. A JWT token is simply a signed JSON object. It can be used anywhere such a thing is useful. There is some confusion, though, as JWT is the most common type of bearer token used in OAuth2 authentication.
-
-Without going too far down the rabbit hole, here's a description of the interaction of these technologies:
-
-* OAuth is a protocol for allowing an identity provider to be separate from the service a user is logging in to. For example, whenever you use Facebook to log into a different service (Yelp, Spotify, etc), you are using OAuth.
-* OAuth defines several options for passing around authentication data. One popular method is called a "bearer token". A bearer token is simply a string that _should_ only be held by an authenticated user. Thus, simply presenting this token proves your identity. You can probably derive from here why a JWT might make a good bearer token.
-* Because bearer tokens are used for authentication, it's important they're kept secret. This is why transactions that use bearer tokens typically happen over SSL.
-
-### Troubleshooting
-
-This library uses descriptive error messages whenever possible. If you are not getting the expected result, have a look at the errors. The most common place people get stuck is providing the correct type of key to the parser. See the above section on signing methods and key types.
-
-## More
-
-Documentation can be found [on pkg.go.dev](https://pkg.go.dev/github.com/golang-jwt/jwt).
-
-The command line utility included in this project (cmd/jwt) provides a straightforward example of token creation and parsing as well as a useful tool for debugging your own integration. You'll also find several implementation examples in the documentation.

vendor/github.com/golang-jwt/jwt/claims.go

@@ -1,146 +0,0 @@
-package jwt
-
-import (
-	"crypto/subtle"
-	"fmt"
-	"time"
-)
-
-// For a type to be a Claims object, it must just have a Valid method that determines
-// if the token is invalid for any supported reason
-type Claims interface {
-	Valid() error
-}
-
-// Structured version of Claims Section, as referenced at
-// https://tools.ietf.org/html/rfc7519#section-4.1
-// See examples for how to use this with your own claim types
-type StandardClaims struct {
-	Audience  string `json:"aud,omitempty"`
-	ExpiresAt int64  `json:"exp,omitempty"`
-	Id        string `json:"jti,omitempty"`
-	IssuedAt  int64  `json:"iat,omitempty"`
-	Issuer    string `json:"iss,omitempty"`
-	NotBefore int64  `json:"nbf,omitempty"`
-	Subject   string `json:"sub,omitempty"`
-}
-
-// Validates time based claims "exp, iat, nbf".
-// There is no accounting for clock skew.
-// As well, if any of the above claims are not in the token, it will still
-// be considered a valid claim.
-func (c StandardClaims) Valid() error {
-	vErr := new(ValidationError)
-	now := TimeFunc().Unix()
-
-	// The claims below are optional, by default, so if they are set to the
-	// default value in Go, let's not fail the verification for them.
-	if !c.VerifyExpiresAt(now, false) {
-		delta := time.Unix(now, 0).Sub(time.Unix(c.ExpiresAt, 0))
-		vErr.Inner = fmt.Errorf("token is expired by %v", delta)
-		vErr.Errors |= ValidationErrorExpired
-	}
-
-	if !c.VerifyIssuedAt(now, false) {
-		vErr.Inner = fmt.Errorf("Token used before issued")
-		vErr.Errors |= ValidationErrorIssuedAt
-	}
-
-	if !c.VerifyNotBefore(now, false) {
-		vErr.Inner = fmt.Errorf("token is not valid yet")
-		vErr.Errors |= ValidationErrorNotValidYet
-	}
-
-	if vErr.valid() {
-		return nil
-	}
-
-	return vErr
-}
-
-// Compares the aud claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (c *StandardClaims) VerifyAudience(cmp string, req bool) bool {
-	return verifyAud([]string{c.Audience}, cmp, req)
-}
-
-// Compares the exp claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (c *StandardClaims) VerifyExpiresAt(cmp int64, req bool) bool {
-	return verifyExp(c.ExpiresAt, cmp, req)
-}
-
-// Compares the iat claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (c *StandardClaims) VerifyIssuedAt(cmp int64, req bool) bool {
-	return verifyIat(c.IssuedAt, cmp, req)
-}
-
-// Compares the iss claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (c *StandardClaims) VerifyIssuer(cmp string, req bool) bool {
-	return verifyIss(c.Issuer, cmp, req)
-}
-
-// Compares the nbf claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (c *StandardClaims) VerifyNotBefore(cmp int64, req bool) bool {
-	return verifyNbf(c.NotBefore, cmp, req)
-}
-
-// ----- helpers
-
-func verifyAud(aud []string, cmp string, required bool) bool {
-	if len(aud) == 0 {
-		return !required
-	}
-	// use a var here to keep constant time compare when looping over a number of claims
-	result := false
-
-	var stringClaims string
-	for _, a := range aud {
-		if subtle.ConstantTimeCompare([]byte(a), []byte(cmp)) != 0 {
-			result = true
-		}
-		stringClaims = stringClaims + a
-	}
-
-	// case where "" is sent in one or many aud claims
-	if len(stringClaims) == 0 {
-		return !required
-	}
-
-	return result
-}
-
-func verifyExp(exp int64, now int64, required bool) bool {
-	if exp == 0 {
-		return !required
-	}
-	return now <= exp
-}
-
-func verifyIat(iat int64, now int64, required bool) bool {
-	if iat == 0 {
-		return !required
-	}
-	return now >= iat
-}
-
-func verifyIss(iss string, cmp string, required bool) bool {
-	if iss == "" {
-		return !required
-	}
-	if subtle.ConstantTimeCompare([]byte(iss), []byte(cmp)) != 0 {
-		return true
-	} else {
-		return false
-	}
-}
-
-func verifyNbf(nbf int64, now int64, required bool) bool {
-	if nbf == 0 {
-		return !required
-	}
-	return now >= nbf
-}

vendor/github.com/golang-jwt/jwt/errors.go

@@ -1,59 +0,0 @@
-package jwt
-
-import (
-	"errors"
-)
-
-// Error constants
-var (
-	ErrInvalidKey      = errors.New("key is invalid")
-	ErrInvalidKeyType  = errors.New("key is of invalid type")
-	ErrHashUnavailable = errors.New("the requested hash function is unavailable")
-)
-
-// The errors that might occur when parsing and validating a token
-const (
-	ValidationErrorMalformed        uint32 = 1 << iota // Token is malformed
-	ValidationErrorUnverifiable                        // Token could not be verified because of signing problems
-	ValidationErrorSignatureInvalid                    // Signature validation failed
-
-	// Standard Claim validation errors
-	ValidationErrorAudience      // AUD validation failed
-	ValidationErrorExpired       // EXP validation failed
-	ValidationErrorIssuedAt      // IAT validation failed
-	ValidationErrorIssuer        // ISS validation failed
-	ValidationErrorNotValidYet   // NBF validation failed
-	ValidationErrorId            // JTI validation failed
-	ValidationErrorClaimsInvalid // Generic claims validation error
-)
-
-// Helper for constructing a ValidationError with a string error message
-func NewValidationError(errorText string, errorFlags uint32) *ValidationError {
-	return &ValidationError{
-		text:   errorText,
-		Errors: errorFlags,
-	}
-}
-
-// The error from Parse if token is not valid
-type ValidationError struct {
-	Inner  error  // stores the error returned by external dependencies, i.e.: KeyFunc
-	Errors uint32 // bitfield.  see ValidationError... constants
-	text   string // errors that do not have a valid error just have text
-}
-
-// Validation error is an error type
-func (e ValidationError) Error() string {
-	if e.Inner != nil {
-		return e.Inner.Error()
-	} else if e.text != "" {
-		return e.text
-	} else {
-		return "token is invalid"
-	}
-}
-
-// No errors
-func (e *ValidationError) valid() bool {
-	return e.Errors == 0
-}

vendor/github.com/golang-jwt/jwt/map_claims.go

@@ -1,120 +0,0 @@
-package jwt
-
-import (
-	"encoding/json"
-	"errors"
-	// "fmt"
-)
-
-// Claims type that uses the map[string]interface{} for JSON decoding
-// This is the default claims type if you don't supply one
-type MapClaims map[string]interface{}
-
-// VerifyAudience Compares the aud claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (m MapClaims) VerifyAudience(cmp string, req bool) bool {
-	var aud []string
-	switch v := m["aud"].(type) {
-	case string:
-		aud = append(aud, v)
-	case []string:
-		aud = v
-	case []interface{}:
-		for _, a := range v {
-			vs, ok := a.(string)
-			if !ok {
-				return false
-			}
-			aud = append(aud, vs)
-		}
-	}
-	return verifyAud(aud, cmp, req)
-}
-
-// Compares the exp claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (m MapClaims) VerifyExpiresAt(cmp int64, req bool) bool {
-	exp, ok := m["exp"]
-	if !ok {
-		return !req
-	}
-	switch expType := exp.(type) {
-	case float64:
-		return verifyExp(int64(expType), cmp, req)
-	case json.Number:
-		v, _ := expType.Int64()
-		return verifyExp(v, cmp, req)
-	}
-	return false
-}
-
-// Compares the iat claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (m MapClaims) VerifyIssuedAt(cmp int64, req bool) bool {
-	iat, ok := m["iat"]
-	if !ok {
-		return !req
-	}
-	switch iatType := iat.(type) {
-	case float64:
-		return verifyIat(int64(iatType), cmp, req)
-	case json.Number:
-		v, _ := iatType.Int64()
-		return verifyIat(v, cmp, req)
-	}
-	return false
-}
-
-// Compares the iss claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (m MapClaims) VerifyIssuer(cmp string, req bool) bool {
-	iss, _ := m["iss"].(string)
-	return verifyIss(iss, cmp, req)
-}
-
-// Compares the nbf claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (m MapClaims) VerifyNotBefore(cmp int64, req bool) bool {
-	nbf, ok := m["nbf"]
-	if !ok {
-		return !req
-	}
-	switch nbfType := nbf.(type) {
-	case float64:
-		return verifyNbf(int64(nbfType), cmp, req)
-	case json.Number:
-		v, _ := nbfType.Int64()
-		return verifyNbf(v, cmp, req)
-	}
-	return false
-}
-
-// Validates time based claims "exp, iat, nbf".
-// There is no accounting for clock skew.
-// As well, if any of the above claims are not in the token, it will still
-// be considered a valid claim.
-func (m MapClaims) Valid() error {
-	vErr := new(ValidationError)
-	now := TimeFunc().Unix()
-
-	if !m.VerifyExpiresAt(now, false) {
-		vErr.Inner = errors.New("Token is expired")
-		vErr.Errors |= ValidationErrorExpired
-	}
-
-	if !m.VerifyIssuedAt(now, false) {
-		vErr.Inner = errors.New("Token used before issued")
-		vErr.Errors |= ValidationErrorIssuedAt
-	}
-
-	if !m.VerifyNotBefore(now, false) {
-		vErr.Inner = errors.New("Token is not valid yet")
-		vErr.Errors |= ValidationErrorNotValidYet
-	}
-
-	if vErr.valid() {
-		return nil
-	}
-
-	return vErr
-}

vendor/github.com/golang-jwt/jwt/parser.go

@@ -1,148 +0,0 @@
-package jwt
-
-import (
-	"bytes"
-	"encoding/json"
-	"fmt"
-	"strings"
-)
-
-type Parser struct {
-	ValidMethods         []string // If populated, only these methods will be considered valid
-	UseJSONNumber        bool     // Use JSON Number format in JSON decoder
-	SkipClaimsValidation bool     // Skip claims validation during token parsing
-}
-
-// Parse, validate, and return a token.
-// keyFunc will receive the parsed token and should return the key for validating.
-// If everything is kosher, err will be nil
-func (p *Parser) Parse(tokenString string, keyFunc Keyfunc) (*Token, error) {
-	return p.ParseWithClaims(tokenString, MapClaims{}, keyFunc)
-}
-
-func (p *Parser) ParseWithClaims(tokenString string, claims Claims, keyFunc Keyfunc) (*Token, error) {
-	token, parts, err := p.ParseUnverified(tokenString, claims)
-	if err != nil {
-		return token, err
-	}
-
-	// Verify signing method is in the required set
-	if p.ValidMethods != nil {
-		var signingMethodValid = false
-		var alg = token.Method.Alg()
-		for _, m := range p.ValidMethods {
-			if m == alg {
-				signingMethodValid = true
-				break
-			}
-		}
-		if !signingMethodValid {
-			// signing method is not in the listed set
-			return token, NewValidationError(fmt.Sprintf("signing method %v is invalid", alg), ValidationErrorSignatureInvalid)
-		}
-	}
-
-	// Lookup key
-	var key interface{}
-	if keyFunc == nil {
-		// keyFunc was not provided.  short circuiting validation
-		return token, NewValidationError("no Keyfunc was provided.", ValidationErrorUnverifiable)
-	}
-	if key, err = keyFunc(token); err != nil {
-		// keyFunc returned an error
-		if ve, ok := err.(*ValidationError); ok {
-			return token, ve
-		}
-		return token, &ValidationError{Inner: err, Errors: ValidationErrorUnverifiable}
-	}
-
-	vErr := &ValidationError{}
-
-	// Validate Claims
-	if !p.SkipClaimsValidation {
-		if err := token.Claims.Valid(); err != nil {
-
-			// If the Claims Valid returned an error, check if it is a validation error,
-			// If it was another error type, create a ValidationError with a generic ClaimsInvalid flag set
-			if e, ok := err.(*ValidationError); !ok {
-				vErr = &ValidationError{Inner: err, Errors: ValidationErrorClaimsInvalid}
-			} else {
-				vErr = e
-			}
-		}
-	}
-
-	// Perform validation
-	token.Signature = parts[2]
-	if err = token.Method.Verify(strings.Join(parts[0:2], "."), token.Signature, key); err != nil {
-		vErr.Inner = err
-		vErr.Errors |= ValidationErrorSignatureInvalid
-	}
-
-	if vErr.valid() {
-		token.Valid = true
-		return token, nil
-	}
-
-	return token, vErr
-}
-
-// WARNING: Don't use this method unless you know what you're doing
-//
-// This method parses the token but doesn't validate the signature. It's only
-// ever useful in cases where you know the signature is valid (because it has
-// been checked previously in the stack) and you want to extract values from
-// it.
-func (p *Parser) ParseUnverified(tokenString string, claims Claims) (token *Token, parts []string, err error) {
-	parts = strings.Split(tokenString, ".")
-	if len(parts) != 3 {
-		return nil, parts, NewValidationError("token contains an invalid number of segments", ValidationErrorMalformed)
-	}
-
-	token = &Token{Raw: tokenString}
-
-	// parse Header
-	var headerBytes []byte
-	if headerBytes, err = DecodeSegment(parts[0]); err != nil {
-		if strings.HasPrefix(strings.ToLower(tokenString), "bearer ") {
-			return token, parts, NewValidationError("tokenstring should not contain 'bearer '", ValidationErrorMalformed)
-		}
-		return token, parts, &ValidationError{Inner: err, Errors: ValidationErrorMalformed}
-	}
-	if err = json.Unmarshal(headerBytes, &token.Header); err != nil {
-		return token, parts, &ValidationError{Inner: err, Errors: ValidationErrorMalformed}
-	}
-
-	// parse Claims
-	var claimBytes []byte
-	token.Claims = claims
-
-	if claimBytes, err = DecodeSegment(parts[1]); err != nil {
-		return token, parts, &ValidationError{Inner: err, Errors: ValidationErrorMalformed}
-	}
-	dec := json.NewDecoder(bytes.NewBuffer(claimBytes))
-	if p.UseJSONNumber {
-		dec.UseNumber()
-	}
-	// JSON Decode.  Special case for map type to avoid weird pointer behavior
-	if c, ok := token.Claims.(MapClaims); ok {
-		err = dec.Decode(&c)
-	} else {
-		err = dec.Decode(&claims)
-	}
-	// Handle decode error
-	if err != nil {
-		return token, parts, &ValidationError{Inner: err, Errors: ValidationErrorMalformed}
-	}
-
-	// Lookup signature method
-	if method, ok := token.Header["alg"].(string); ok {
-		if token.Method = GetSigningMethod(method); token.Method == nil {
-			return token, parts, NewValidationError("signing method (alg) is unavailable.", ValidationErrorUnverifiable)
-		}
-	} else {
-		return token, parts, NewValidationError("signing method (alg) is unspecified.", ValidationErrorUnverifiable)
-	}
-
-	return token, parts, nil
-}

vendor/github.com/golang-jwt/jwt/signing_method.go

@@ -1,35 +0,0 @@
-package jwt
-
-import (
-	"sync"
-)
-
-var signingMethods = map[string]func() SigningMethod{}
-var signingMethodLock = new(sync.RWMutex)
-
-// Implement SigningMethod to add new methods for signing or verifying tokens.
-type SigningMethod interface {
-	Verify(signingString, signature string, key interface{}) error // Returns nil if signature is valid
-	Sign(signingString string, key interface{}) (string, error)    // Returns encoded signature or error
-	Alg() string                                                   // returns the alg identifier for this method (example: 'HS256')
-}
-
-// Register the "alg" name and a factory function for signing method.
-// This is typically done during init() in the method's implementation
-func RegisterSigningMethod(alg string, f func() SigningMethod) {
-	signingMethodLock.Lock()
-	defer signingMethodLock.Unlock()
-
-	signingMethods[alg] = f
-}
-
-// Get a signing method from an "alg" string
-func GetSigningMethod(alg string) (method SigningMethod) {
-	signingMethodLock.RLock()
-	defer signingMethodLock.RUnlock()
-
-	if methodF, ok := signingMethods[alg]; ok {
-		method = methodF()
-	}
-	return
-}

vendor/github.com/golang-jwt/jwt/token.go

@@ -1,104 +0,0 @@
-package jwt
-
-import (
-	"encoding/base64"
-	"encoding/json"
-	"strings"
-	"time"
-)
-
-// TimeFunc provides the current time when parsing token to validate "exp" claim (expiration time).
-// You can override it to use another time value.  This is useful for testing or if your
-// server uses a different time zone than your tokens.
-var TimeFunc = time.Now
-
-// Parse methods use this callback function to supply
-// the key for verification.  The function receives the parsed,
-// but unverified Token.  This allows you to use properties in the
-// Header of the token (such as `kid`) to identify which key to use.
-type Keyfunc func(*Token) (interface{}, error)
-
-// A JWT Token.  Different fields will be used depending on whether you're
-// creating or parsing/verifying a token.
-type Token struct {
-	Raw       string                 // The raw token.  Populated when you Parse a token
-	Method    SigningMethod          // The signing method used or to be used
-	Header    map[string]interface{} // The first segment of the token
-	Claims    Claims                 // The second segment of the token
-	Signature string                 // The third segment of the token.  Populated when you Parse a token
-	Valid     bool                   // Is the token valid?  Populated when you Parse/Verify a token
-}
-
-// Create a new Token.  Takes a signing method
-func New(method SigningMethod) *Token {
-	return NewWithClaims(method, MapClaims{})
-}
-
-func NewWithClaims(method SigningMethod, claims Claims) *Token {
-	return &Token{
-		Header: map[string]interface{}{
-			"typ": "JWT",
-			"alg": method.Alg(),
-		},
-		Claims: claims,
-		Method: method,
-	}
-}
-
-// Get the complete, signed token
-func (t *Token) SignedString(key interface{}) (string, error) {
-	var sig, sstr string
-	var err error
-	if sstr, err = t.SigningString(); err != nil {
-		return "", err
-	}
-	if sig, err = t.Method.Sign(sstr, key); err != nil {
-		return "", err
-	}
-	return strings.Join([]string{sstr, sig}, "."), nil
-}
-
-// Generate the signing string.  This is the
-// most expensive part of the whole deal.  Unless you
-// need this for something special, just go straight for
-// the SignedString.
-func (t *Token) SigningString() (string, error) {
-	var err error
-	parts := make([]string, 2)
-	for i := range parts {
-		var jsonValue []byte
-		if i == 0 {
-			if jsonValue, err = json.Marshal(t.Header); err != nil {
-				return "", err
-			}
-		} else {
-			if jsonValue, err = json.Marshal(t.Claims); err != nil {
-				return "", err
-			}
-		}
-
-		parts[i] = EncodeSegment(jsonValue)
-	}
-	return strings.Join(parts, "."), nil
-}
-
-// Parse, validate, and return a token.
-// keyFunc will receive the parsed token and should return the key for validating.
-// If everything is kosher, err will be nil
-func Parse(tokenString string, keyFunc Keyfunc) (*Token, error) {
-	return new(Parser).Parse(tokenString, keyFunc)
-}
-
-func ParseWithClaims(tokenString string, claims Claims, keyFunc Keyfunc) (*Token, error) {
-	return new(Parser).ParseWithClaims(tokenString, claims, keyFunc)
-}
-
-// Encode JWT specific base64url encoding with padding stripped
-func EncodeSegment(seg []byte) string {
-	return base64.RawURLEncoding.EncodeToString(seg)
-}
-
-// Decode JWT specific base64url encoding with padding stripped
-func DecodeSegment(seg string) ([]byte, error) {
-	return base64.RawURLEncoding.DecodeString(seg)
-}

vendor/github.com/golang-jwt/jwt/v5/MIGRATION_GUIDE.md

@@ -0,0 +1,195 @@
+# Migration Guide (v5.0.0)
+
+Version `v5` contains a major rework of core functionalities in the `jwt-go`
+library. This includes support for several validation options as well as a
+re-design of the `Claims` interface. Lastly, we reworked how errors work under
+the hood, which should provide a better overall developer experience.
+
+Starting from [v5.0.0](https://github.com/golang-jwt/jwt/releases/tag/v5.0.0),
+the import path will be:
+
+    "github.com/golang-jwt/jwt/v5"
+
+For most users, changing the import path *should* suffice. However, since we
+intentionally changed and cleaned some of the public API, existing programs
+might need to be updated. The following sections describe significant changes
+and corresponding updates for existing programs.
+
+## Parsing and Validation Options
+
+Under the hood, a new `Validator` struct takes care of validating the claims. A
+long awaited feature has been the option to fine-tune the validation of tokens.
+This is now possible with several `ParserOption` functions that can be appended
+to most `Parse` functions, such as `ParseWithClaims`. The most important options
+and changes are:
+  * Added `WithLeeway` to support specifying the leeway that is allowed when
+    validating time-based claims, such as `exp` or `nbf`.
+  * Changed default behavior to not check the `iat` claim. Usage of this claim
+    is OPTIONAL according to the JWT RFC. The claim itself is also purely
+    informational according to the RFC, so a strict validation failure is not
+    recommended. If you want to check for sensible values in these claims,
+    please use the `WithIssuedAt` parser option.
+  * Added `WithAudience`, `WithSubject` and `WithIssuer` to support checking for
+    expected `aud`, `sub` and `iss`.
+  * Added `WithStrictDecoding` and `WithPaddingAllowed` options to allow
+    previously global settings to enable base64 strict encoding and the parsing
+    of base64 strings with padding. The latter is strictly speaking against the
+    standard, but unfortunately some of the major identity providers issue some
+    of these incorrect tokens. Both options are disabled by default.
+
+## Changes to the `Claims` interface
+
+### Complete Restructuring
+
+Previously, the claims interface was satisfied with an implementation of a
+`Valid() error` function. This had several issues:
+  * The different claim types (struct claims, map claims, etc.) then contained
+    similar (but not 100 % identical) code of how this validation was done. This
+    lead to a lot of (almost) duplicate code and was hard to maintain
+  * It was not really semantically close to what a "claim" (or a set of claims)
+    really is; which is a list of defined key/value pairs with a certain
+    semantic meaning.
+
+Since all the validation functionality is now extracted into the validator, all
+`VerifyXXX` and `Valid` functions have been removed from the `Claims` interface.
+Instead, the interface now represents a list of getters to retrieve values with
+a specific meaning. This allows us to completely decouple the validation logic
+with the underlying storage representation of the claim, which could be a
+struct, a map or even something stored in a database.
+
+```go
+type Claims interface {
+	GetExpirationTime() (*NumericDate, error)
+	GetIssuedAt() (*NumericDate, error)
+	GetNotBefore() (*NumericDate, error)
+	GetIssuer() (string, error)
+	GetSubject() (string, error)
+	GetAudience() (ClaimStrings, error)
+}
+```
+
+Users that previously directly called the `Valid` function on their claims,
+e.g., to perform validation independently of parsing/verifying a token, can now
+use the `jwt.NewValidator` function to create a `Validator` independently of the
+`Parser`.
+
+```go
+var v = jwt.NewValidator(jwt.WithLeeway(5*time.Second))
+v.Validate(myClaims)
+```
+
+### Supported Claim Types and Removal of `StandardClaims`
+
+The two standard claim types supported by this library, `MapClaims` and
+`RegisteredClaims` both implement the necessary functions of this interface. The
+old `StandardClaims` struct, which has already been deprecated in `v4` is now
+removed.
+
+Users using custom claims, in most cases, will not experience any changes in the
+behavior as long as they embedded `RegisteredClaims`. If they created a new
+claim type from scratch, they now need to implemented the proper getter
+functions.
+
+### Migrating Application Specific Logic of the old `Valid`
+
+Previously, users could override the `Valid` method in a custom claim, for
+example to extend the validation with application-specific claims. However, this
+was always very dangerous, since once could easily disable the standard
+validation and signature checking.
+
+In order to avoid that, while still supporting the use-case, a new
+`ClaimsValidator` interface has been introduced. This interface consists of the
+`Validate() error` function. If the validator sees, that a `Claims` struct
+implements this interface, the errors returned to the `Validate` function will
+be *appended* to the regular standard validation. It is not possible to disable
+the standard validation anymore (even only by accident).
+
+Usage examples can be found in [example_test.go](./example_test.go), to build
+claims structs like the following.
+
+```go
+// MyCustomClaims includes all registered claims, plus Foo.
+type MyCustomClaims struct {
+	Foo string `json:"foo"`
+	jwt.RegisteredClaims
+}
+
+// Validate can be used to execute additional application-specific claims
+// validation.
+func (m MyCustomClaims) Validate() error {
+	if m.Foo != "bar" {
+		return errors.New("must be foobar")
+	}
+
+	return nil
+}
+```
+
+## Changes to the `Token` and `Parser` struct
+
+The previously global functions `DecodeSegment` and `EncodeSegment` were moved
+to the `Parser` and `Token` struct respectively. This will allow us in the
+future to configure the behavior of these two based on options supplied on the
+parser or the token (creation). This also removes two previously global
+variables and moves them to parser options `WithStrictDecoding` and
+`WithPaddingAllowed`.
+
+In order to do that, we had to adjust the way signing methods work. Previously
+they were given a base64 encoded signature in `Verify` and were expected to
+return a base64 encoded version of the signature in `Sign`, both as a `string`.
+However, this made it necessary to have `DecodeSegment` and `EncodeSegment`
+global and was a less than perfect design because we were repeating
+encoding/decoding steps for all signing methods. Now, `Sign` and `Verify`
+operate on a decoded signature as a `[]byte`, which feels more natural for a
+cryptographic operation anyway. Lastly, `Parse` and `SignedString` take care of
+the final encoding/decoding part.
+
+In addition to that, we also changed the `Signature` field on `Token` from a
+`string` to `[]byte` and this is also now populated with the decoded form. This
+is also more consistent, because the other parts of the JWT, mainly `Header` and
+`Claims` were already stored in decoded form in `Token`. Only the signature was
+stored in base64 encoded form, which was redundant with the information in the
+`Raw` field, which contains the complete token as base64.
+
+```go
+type Token struct {
+	Raw       string                 // Raw contains the raw token
+	Method    SigningMethod          // Method is the signing method used or to be used
+	Header    map[string]interface{} // Header is the first segment of the token in decoded form
+	Claims    Claims                 // Claims is the second segment of the token in decoded form
+	Signature []byte                 // Signature is the third segment of the token in decoded form
+	Valid     bool                   // Valid specifies if the token is valid
+}
+```
+
+Most (if not all) of these changes should not impact the normal usage of this
+library. Only users directly accessing the `Signature` field as well as
+developers of custom signing methods should be affected.
+
+# Migration Guide (v4.0.0)
+
+Starting from [v4.0.0](https://github.com/golang-jwt/jwt/releases/tag/v4.0.0),
+the import path will be:
+
+    "github.com/golang-jwt/jwt/v4"
+
+The `/v4` version will be backwards compatible with existing `v3.x.y` tags in
+this repo, as well as `github.com/dgrijalva/jwt-go`. For most users this should
+be a drop-in replacement, if you're having troubles migrating, please open an
+issue.
+
+You can replace all occurrences of `github.com/dgrijalva/jwt-go` or
+`github.com/golang-jwt/jwt` with `github.com/golang-jwt/jwt/v4`, either manually
+or by using tools such as `sed` or `gofmt`.
+
+And then you'd typically run:
+
+```
+go get github.com/golang-jwt/jwt/v4
+go mod tidy
+```
+
+# Older releases (before v3.2.0)
+
+The original migration guide for older releases can be found at
+https://github.com/dgrijalva/jwt-go/blob/master/MIGRATION_GUIDE.md.

vendor/github.com/golang-jwt/jwt/v5/README.md

@@ -0,0 +1,167 @@
+# jwt-go
+
+[![build](https://github.com/golang-jwt/jwt/actions/workflows/build.yml/badge.svg)](https://github.com/golang-jwt/jwt/actions/workflows/build.yml)
+[![Go
+Reference](https://pkg.go.dev/badge/github.com/golang-jwt/jwt/v5.svg)](https://pkg.go.dev/github.com/golang-jwt/jwt/v5)
+[![Coverage Status](https://coveralls.io/repos/github/golang-jwt/jwt/badge.svg?branch=main)](https://coveralls.io/github/golang-jwt/jwt?branch=main)
+
+A [go](http://www.golang.org) (or 'golang' for search engine friendliness)
+implementation of [JSON Web
+Tokens](https://datatracker.ietf.org/doc/html/rfc7519).
+
+Starting with [v4.0.0](https://github.com/golang-jwt/jwt/releases/tag/v4.0.0)
+this project adds Go module support, but maintains backwards compatibility with
+older `v3.x.y` tags and upstream `github.com/dgrijalva/jwt-go`. See the
+[`MIGRATION_GUIDE.md`](./MIGRATION_GUIDE.md) for more information. Version
+v5.0.0 introduces major improvements to the validation of tokens, but is not
+entirely backwards compatible. 
+
+> After the original author of the library suggested migrating the maintenance
+> of `jwt-go`, a dedicated team of open source maintainers decided to clone the
+> existing library into this repository. See
+> [dgrijalva/jwt-go#462](https://github.com/dgrijalva/jwt-go/issues/462) for a
+> detailed discussion on this topic.
+
+
+**SECURITY NOTICE:** Some older versions of Go have a security issue in the
+crypto/elliptic. Recommendation is to upgrade to at least 1.15 See issue
+[dgrijalva/jwt-go#216](https://github.com/dgrijalva/jwt-go/issues/216) for more
+detail.
+
+**SECURITY NOTICE:** It's important that you [validate the `alg` presented is
+what you
+expect](https://auth0.com/blog/critical-vulnerabilities-in-json-web-token-libraries/).
+This library attempts to make it easy to do the right thing by requiring key
+types match the expected alg, but you should take the extra step to verify it in
+your usage.  See the examples provided.
+
+### Supported Go versions
+
+Our support of Go versions is aligned with Go's [version release
+policy](https://golang.org/doc/devel/release#policy). So we will support a major
+version of Go until there are two newer major releases. We no longer support
+building jwt-go with unsupported Go versions, as these contain security
+vulnerabilities which will not be fixed.
+
+## What the heck is a JWT?
+
+JWT.io has [a great introduction](https://jwt.io/introduction) to JSON Web
+Tokens.
+
+In short, it's a signed JSON object that does something useful (for example,
+authentication).  It's commonly used for `Bearer` tokens in Oauth 2.  A token is
+made of three parts, separated by `.`'s.  The first two parts are JSON objects,
+that have been [base64url](https://datatracker.ietf.org/doc/html/rfc4648)
+encoded.  The last part is the signature, encoded the same way.
+
+The first part is called the header.  It contains the necessary information for
+verifying the last part, the signature.  For example, which encryption method
+was used for signing and what key was used.
+
+The part in the middle is the interesting bit.  It's called the Claims and
+contains the actual stuff you care about.  Refer to [RFC
+7519](https://datatracker.ietf.org/doc/html/rfc7519) for information about
+reserved keys and the proper way to add your own.
+
+## What's in the box?
+
+This library supports the parsing and verification as well as the generation and
+signing of JWTs.  Current supported signing algorithms are HMAC SHA, RSA,
+RSA-PSS, and ECDSA, though hooks are present for adding your own.
+
+## Installation Guidelines
+
+1. To install the jwt package, you first need to have
+   [Go](https://go.dev/doc/install) installed, then you can use the command
+   below to add `jwt-go` as a dependency in your Go program.
+
+```sh
+go get -u github.com/golang-jwt/jwt/v5
+```
+
+2. Import it in your code:
+
+```go
+import "github.com/golang-jwt/jwt/v5"
+```
+
+## Usage
+
+A detailed usage guide, including how to sign and verify tokens can be found on
+our [documentation website](https://golang-jwt.github.io/jwt/usage/create/).
+
+## Examples
+
+See [the project documentation](https://pkg.go.dev/github.com/golang-jwt/jwt/v5)
+for examples of usage:
+
+* [Simple example of parsing and validating a
+  token](https://pkg.go.dev/github.com/golang-jwt/jwt/v5#example-Parse-Hmac)
+* [Simple example of building and signing a
+  token](https://pkg.go.dev/github.com/golang-jwt/jwt/v5#example-New-Hmac)
+* [Directory of
+  Examples](https://pkg.go.dev/github.com/golang-jwt/jwt/v5#pkg-examples)
+
+## Compliance
+
+This library was last reviewed to comply with [RFC
+7519](https://datatracker.ietf.org/doc/html/rfc7519) dated May 2015 with a few
+notable differences:
+
+* In order to protect against accidental use of [Unsecured
+  JWTs](https://datatracker.ietf.org/doc/html/rfc7519#section-6), tokens using
+  `alg=none` will only be accepted if the constant
+  `jwt.UnsafeAllowNoneSignatureType` is provided as the key.
+
+## Project Status & Versioning
+
+This library is considered production ready.  Feedback and feature requests are
+appreciated.  The API should be considered stable.  There should be very few
+backwards-incompatible changes outside of major version updates (and only with
+good reason).
+
+This project uses [Semantic Versioning 2.0.0](http://semver.org).  Accepted pull
+requests will land on `main`.  Periodically, versions will be tagged from
+`main`.  You can find all the releases on [the project releases
+page](https://github.com/golang-jwt/jwt/releases).
+
+**BREAKING CHANGES:*** A full list of breaking changes is available in
+`VERSION_HISTORY.md`.  See `MIGRATION_GUIDE.md` for more information on updating
+your code.
+
+## Extensions
+
+This library publishes all the necessary components for adding your own signing
+methods or key functions.  Simply implement the `SigningMethod` interface and
+register a factory method using `RegisterSigningMethod` or provide a
+`jwt.Keyfunc`.
+
+A common use case would be integrating with different 3rd party signature
+providers, like key management services from various cloud providers or Hardware
+Security Modules (HSMs) or to implement additional standards.
+
+| Extension | Purpose                                                                                                  | Repo                                       |
+| --------- | -------------------------------------------------------------------------------------------------------- | ------------------------------------------ |
+| GCP       | Integrates with multiple Google Cloud Platform signing tools (AppEngine, IAM API, Cloud KMS)             | https://github.com/someone1/gcp-jwt-go     |
+| AWS       | Integrates with AWS Key Management Service, KMS                                                          | https://github.com/matelang/jwt-go-aws-kms |
+| JWKS      | Provides support for JWKS ([RFC 7517](https://datatracker.ietf.org/doc/html/rfc7517)) as a `jwt.Keyfunc` | https://github.com/MicahParks/keyfunc      |
+
+*Disclaimer*: Unless otherwise specified, these integrations are maintained by
+third parties and should not be considered as a primary offer by any of the
+mentioned cloud providers
+
+## More
+
+Go package documentation can be found [on
+pkg.go.dev](https://pkg.go.dev/github.com/golang-jwt/jwt/v5). Additional
+documentation can be found on [our project
+page](https://golang-jwt.github.io/jwt/).
+
+The command line utility included in this project (cmd/jwt) provides a
+straightforward example of token creation and parsing as well as a useful tool
+for debugging your own integration. You'll also find several implementation
+examples in the documentation.
+
+[golang-jwt](https://github.com/orgs/golang-jwt) incorporates a modified version
+of the JWT logo, which is distributed under the terms of the [MIT
+License](https://github.com/jsonwebtoken/jsonwebtoken.github.io/blob/master/LICENSE.txt).

vendor/github.com/golang-jwt/jwt/v5/SECURITY.md

@@ -0,0 +1,19 @@
+# Security Policy
+
+## Supported Versions
+
+As of February 2022 (and until this document is updated), the latest version `v4` is supported.
+
+## Reporting a Vulnerability
+
+If you think you found a vulnerability, and even if you are not sure, please report it to jwt-go-security@googlegroups.com or one of the other [golang-jwt maintainers](https://github.com/orgs/golang-jwt/people). Please try be explicit, describe steps to reproduce the security issue with code example(s).
+
+You will receive a response within a timely manner. If the issue is confirmed, we will do our best to release a patch as soon as possible given the complexity of the problem.
+
+## Public Discussions
+
+Please avoid publicly discussing a potential security vulnerability.
+
+Let's take this offline and find a solution first, this limits the potential impact as much as possible.
+
+We appreciate your help!

vendor/github.com/golang-jwt/jwt/v5/VERSION_HISTORY.md

@@ -1,13 +1,19 @@
-## `jwt-go` Version History
+# `jwt-go` Version History
 
-#### 3.2.2
+The following version history is kept for historic purposes. To retrieve the current changes of each version, please refer to the change-log of the specific release versions on https://github.com/golang-jwt/jwt/releases.
+
+## 4.0.0
+
+* Introduces support for Go modules. The `v4` version will be backwards compatible with `v3.x.y`.
+
+## 3.2.2
 
 * Starting from this release, we are adopting the policy to support the most 2 recent versions of Go currently available. By the time of this release, this is Go 1.15 and 1.16 ([#28](https://github.com/golang-jwt/jwt/pull/28)).
 * Fixed a potential issue that could occur when the verification of `exp`, `iat` or `nbf` was not required and contained invalid contents, i.e. non-numeric/date. Thanks for @thaJeztah for making us aware of that and @giorgos-f3 for originally reporting it to the formtech fork ([#40](https://github.com/golang-jwt/jwt/pull/40)).
 * Added support for EdDSA / ED25519 ([#36](https://github.com/golang-jwt/jwt/pull/36)).
 * Optimized allocations ([#33](https://github.com/golang-jwt/jwt/pull/33)).
 
-#### 3.2.1
+## 3.2.1
 
 * **Import Path Change**: See MIGRATION_GUIDE.md for tips on updating your code
 	* Changed the import path from `github.com/dgrijalva/jwt-go` to `github.com/golang-jwt/jwt`
@@ -113,17 +119,17 @@ It is likely the only integration change required here will be to change `func(t
 * Refactored the RSA implementation to be easier to read
 * Exposed helper methods `ParseRSAPrivateKeyFromPEM` and `ParseRSAPublicKeyFromPEM`
 
-#### 1.0.2
+## 1.0.2
 
 * Fixed bug in parsing public keys from certificates
 * Added more tests around the parsing of keys for RS256
 * Code refactoring in RS256 implementation.  No functional changes
 
-#### 1.0.1
+## 1.0.1
 
 * Fixed panic if RS256 signing method was passed an invalid key
 
-#### 1.0.0
+## 1.0.0
 
 * First versioned release
 * API stabilized

vendor/github.com/golang-jwt/jwt/v5/claims.go

@@ -0,0 +1,16 @@
+package jwt
+
+// Claims represent any form of a JWT Claims Set according to
+// https://datatracker.ietf.org/doc/html/rfc7519#section-4. In order to have a
+// common basis for validation, it is required that an implementation is able to
+// supply at least the claim names provided in
+// https://datatracker.ietf.org/doc/html/rfc7519#section-4.1 namely `exp`,
+// `iat`, `nbf`, `iss`, `sub` and `aud`.
+type Claims interface {
+	GetExpirationTime() (*NumericDate, error)
+	GetIssuedAt() (*NumericDate, error)
+	GetNotBefore() (*NumericDate, error)
+	GetIssuer() (string, error)
+	GetSubject() (string, error)
+	GetAudience() (ClaimStrings, error)
+}

vendor/github.com/golang-jwt/jwt/v5/ecdsa.go

@@ -13,7 +13,7 @@ var (
 	ErrECDSAVerification = errors.New("crypto/ecdsa: verification error")
 )
 
-// Implements the ECDSA family of signing methods signing methods
+// SigningMethodECDSA implements the ECDSA family of signing methods.
 // Expects *ecdsa.PrivateKey for signing and *ecdsa.PublicKey for verification
 type SigningMethodECDSA struct {
 	Name      string
@@ -53,24 +53,16 @@ func (m *SigningMethodECDSA) Alg() string {
 	return m.Name
 }
 
-// Implements the Verify method from SigningMethod
+// Verify implements token verification for the SigningMethod.
 // For this verify method, key must be an ecdsa.PublicKey struct
-func (m *SigningMethodECDSA) Verify(signingString, signature string, key interface{}) error {
-	var err error
-
-	// Decode the signature
-	var sig []byte
-	if sig, err = DecodeSegment(signature); err != nil {
-		return err
-	}
-
+func (m *SigningMethodECDSA) Verify(signingString string, sig []byte, key interface{}) error {
 	// Get the key
 	var ecdsaKey *ecdsa.PublicKey
 	switch k := key.(type) {
 	case *ecdsa.PublicKey:
 		ecdsaKey = k
 	default:
-		return ErrInvalidKeyType
+		return newError("ECDSA verify expects *ecsda.PublicKey", ErrInvalidKeyType)
 	}
 
 	if len(sig) != 2*m.KeySize {
@@ -95,21 +87,21 @@ func (m *SigningMethodECDSA) Verify(signingString, signature string, key interfa
 	return ErrECDSAVerification
 }
 
-// Implements the Sign method from SigningMethod
+// Sign implements token signing for the SigningMethod.
 // For this signing method, key must be an ecdsa.PrivateKey struct
-func (m *SigningMethodECDSA) Sign(signingString string, key interface{}) (string, error) {
+func (m *SigningMethodECDSA) Sign(signingString string, key interface{}) ([]byte, error) {
 	// Get the key
 	var ecdsaKey *ecdsa.PrivateKey
 	switch k := key.(type) {
 	case *ecdsa.PrivateKey:
 		ecdsaKey = k
 	default:
-		return "", ErrInvalidKeyType
+		return nil, newError("ECDSA sign expects *ecsda.PrivateKey", ErrInvalidKeyType)
 	}
 
 	// Create the hasher
 	if !m.Hash.Available() {
-		return "", ErrHashUnavailable
+		return nil, ErrHashUnavailable
 	}
 
 	hasher := m.Hash.New()
@@ -120,7 +112,7 @@ func (m *SigningMethodECDSA) Sign(signingString string, key interface{}) (string
 		curveBits := ecdsaKey.Curve.Params().BitSize
 
 		if m.CurveBits != curveBits {
-			return "", ErrInvalidKey
+			return nil, ErrInvalidKey
 		}
 
 		keyBytes := curveBits / 8
@@ -135,8 +127,8 @@ func (m *SigningMethodECDSA) Sign(signingString string, key interface{}) (string
 		r.FillBytes(out[0:keyBytes]) // r is assigned to the first half of output.
 		s.FillBytes(out[keyBytes:])  // s is assigned to the second half of output.
 
-		return EncodeSegment(out), nil
+		return out, nil
 	} else {
-		return "", err
+		return nil, err
 	}
 }

vendor/github.com/golang-jwt/jwt/v5/ecdsa_utils.go

@@ -8,11 +8,11 @@ import (
 )
 
 var (
-	ErrNotECPublicKey  = errors.New("Key is not a valid ECDSA public key")
-	ErrNotECPrivateKey = errors.New("Key is not a valid ECDSA private key")
+	ErrNotECPublicKey  = errors.New("key is not a valid ECDSA public key")
+	ErrNotECPrivateKey = errors.New("key is not a valid ECDSA private key")
 )
 
-// Parse PEM encoded Elliptic Curve Private Key Structure
+// ParseECPrivateKeyFromPEM parses a PEM encoded Elliptic Curve Private Key Structure
 func ParseECPrivateKeyFromPEM(key []byte) (*ecdsa.PrivateKey, error) {
 	var err error
 
@@ -39,7 +39,7 @@ func ParseECPrivateKeyFromPEM(key []byte) (*ecdsa.PrivateKey, error) {
 	return pkey, nil
 }
 
-// Parse PEM encoded PKCS1 or PKCS8 public key
+// ParseECPublicKeyFromPEM parses a PEM encoded PKCS1 or PKCS8 public key
 func ParseECPublicKeyFromPEM(key []byte) (*ecdsa.PublicKey, error) {
 	var err error
 

vendor/github.com/golang-jwt/jwt/v5/ed25519.go

@@ -1,16 +1,17 @@
 package jwt
 
 import (
-	"errors"
-
+	"crypto"
 	"crypto/ed25519"
+	"crypto/rand"
+	"errors"
 )
 
 var (
 	ErrEd25519Verification = errors.New("ed25519: verification error")
 )
 
-// Implements the EdDSA family
+// SigningMethodEd25519 implements the EdDSA family.
 // Expects ed25519.PrivateKey for signing and ed25519.PublicKey for verification
 type SigningMethodEd25519 struct{}
 
@@ -30,27 +31,20 @@ func (m *SigningMethodEd25519) Alg() string {
 	return "EdDSA"
 }
 
-// Implements the Verify method from SigningMethod
+// Verify implements token verification for the SigningMethod.
 // For this verify method, key must be an ed25519.PublicKey
-func (m *SigningMethodEd25519) Verify(signingString, signature string, key interface{}) error {
-	var err error
+func (m *SigningMethodEd25519) Verify(signingString string, sig []byte, key interface{}) error {
 	var ed25519Key ed25519.PublicKey
 	var ok bool
 
 	if ed25519Key, ok = key.(ed25519.PublicKey); !ok {
-		return ErrInvalidKeyType
+		return newError("Ed25519 verify expects ed25519.PublicKey", ErrInvalidKeyType)
 	}
 
 	if len(ed25519Key) != ed25519.PublicKeySize {
 		return ErrInvalidKey
 	}
 
-	// Decode the signature
-	var sig []byte
-	if sig, err = DecodeSegment(signature); err != nil {
-		return err
-	}
-
 	// Verify the signature
 	if !ed25519.Verify(ed25519Key, []byte(signingString), sig) {
 		return ErrEd25519Verification
@@ -59,23 +53,27 @@ func (m *SigningMethodEd25519) Verify(signingString, signature string, key inter
 	return nil
 }
 
-// Implements the Sign method from SigningMethod
+// Sign implements token signing for the SigningMethod.
 // For this signing method, key must be an ed25519.PrivateKey
-func (m *SigningMethodEd25519) Sign(signingString string, key interface{}) (string, error) {
-	var ed25519Key ed25519.PrivateKey
+func (m *SigningMethodEd25519) Sign(signingString string, key interface{}) ([]byte, error) {
+	var ed25519Key crypto.Signer
 	var ok bool
 
-	if ed25519Key, ok = key.(ed25519.PrivateKey); !ok {
-		return "", ErrInvalidKeyType
+	if ed25519Key, ok = key.(crypto.Signer); !ok {
+		return nil, newError("Ed25519 sign expects crypto.Signer", ErrInvalidKeyType)
 	}
 
-	// ed25519.Sign panics if private key not equal to ed25519.PrivateKeySize
-	// this allows to avoid recover usage
-	if len(ed25519Key) != ed25519.PrivateKeySize {
-		return "", ErrInvalidKey
+	if _, ok := ed25519Key.Public().(ed25519.PublicKey); !ok {
+		return nil, ErrInvalidKey
 	}
 
-	// Sign the string and return the encoded result
-	sig := ed25519.Sign(ed25519Key, []byte(signingString))
-	return EncodeSegment(sig), nil
+	// Sign the string and return the result. ed25519 performs a two-pass hash
+	// as part of its algorithm. Therefore, we need to pass a non-prehashed
+	// message into the Sign function, as indicated by crypto.Hash(0)
+	sig, err := ed25519Key.Sign(rand.Reader, []byte(signingString), crypto.Hash(0))
+	if err != nil {
+		return nil, err
+	}
+
+	return sig, nil
 }

vendor/github.com/golang-jwt/jwt/v5/ed25519_utils.go

@@ -9,11 +9,11 @@ import (
 )
 
 var (
-	ErrNotEdPrivateKey = errors.New("Key is not a valid Ed25519 private key")
-	ErrNotEdPublicKey  = errors.New("Key is not a valid Ed25519 public key")
+	ErrNotEdPrivateKey = errors.New("key is not a valid Ed25519 private key")
+	ErrNotEdPublicKey  = errors.New("key is not a valid Ed25519 public key")
 )
 
-// Parse PEM-encoded Edwards curve private key
+// ParseEdPrivateKeyFromPEM parses a PEM-encoded Edwards curve private key
 func ParseEdPrivateKeyFromPEM(key []byte) (crypto.PrivateKey, error) {
 	var err error
 
@@ -38,7 +38,7 @@ func ParseEdPrivateKeyFromPEM(key []byte) (crypto.PrivateKey, error) {
 	return pkey, nil
 }
 
-// Parse PEM-encoded Edwards curve public key
+// ParseEdPublicKeyFromPEM parses a PEM-encoded Edwards curve public key
 func ParseEdPublicKeyFromPEM(key []byte) (crypto.PublicKey, error) {
 	var err error
 

vendor/github.com/golang-jwt/jwt/v5/errors.go

@@ -0,0 +1,49 @@
+package jwt
+
+import (
+	"errors"
+	"strings"
+)
+
+var (
+	ErrInvalidKey                = errors.New("key is invalid")
+	ErrInvalidKeyType            = errors.New("key is of invalid type")
+	ErrHashUnavailable           = errors.New("the requested hash function is unavailable")
+	ErrTokenMalformed            = errors.New("token is malformed")
+	ErrTokenUnverifiable         = errors.New("token is unverifiable")
+	ErrTokenSignatureInvalid     = errors.New("token signature is invalid")
+	ErrTokenRequiredClaimMissing = errors.New("token is missing required claim")
+	ErrTokenInvalidAudience      = errors.New("token has invalid audience")
+	ErrTokenExpired              = errors.New("token is expired")
+	ErrTokenUsedBeforeIssued     = errors.New("token used before issued")
+	ErrTokenInvalidIssuer        = errors.New("token has invalid issuer")
+	ErrTokenInvalidSubject       = errors.New("token has invalid subject")
+	ErrTokenNotValidYet          = errors.New("token is not valid yet")
+	ErrTokenInvalidId            = errors.New("token has invalid id")
+	ErrTokenInvalidClaims        = errors.New("token has invalid claims")
+	ErrInvalidType               = errors.New("invalid type for claim")
+)
+
+// joinedError is an error type that works similar to what [errors.Join]
+// produces, with the exception that it has a nice error string; mainly its
+// error messages are concatenated using a comma, rather than a newline.
+type joinedError struct {
+	errs []error
+}
+
+func (je joinedError) Error() string {
+	msg := []string{}
+	for _, err := range je.errs {
+		msg = append(msg, err.Error())
+	}
+
+	return strings.Join(msg, ", ")
+}
+
+// joinErrors joins together multiple errors. Useful for scenarios where
+// multiple errors next to each other occur, e.g., in claims validation.
+func joinErrors(errs ...error) error {
+	return &joinedError{
+		errs: errs,
+	}
+}

vendor/github.com/golang-jwt/jwt/v5/errors_go1_20.go

@@ -0,0 +1,47 @@
+//go:build go1.20
+// +build go1.20
+
+package jwt
+
+import (
+	"fmt"
+)
+
+// Unwrap implements the multiple error unwrapping for this error type, which is
+// possible in Go 1.20.
+func (je joinedError) Unwrap() []error {
+	return je.errs
+}
+
+// newError creates a new error message with a detailed error message. The
+// message will be prefixed with the contents of the supplied error type.
+// Additionally, more errors, that provide more context can be supplied which
+// will be appended to the message. This makes use of Go 1.20's possibility to
+// include more than one %w formatting directive in [fmt.Errorf].
+//
+// For example,
+//
+//	newError("no keyfunc was provided", ErrTokenUnverifiable)
+//
+// will produce the error string
+//
+//	"token is unverifiable: no keyfunc was provided"
+func newError(message string, err error, more ...error) error {
+	var format string
+	var args []any
+	if message != "" {
+		format = "%w: %s"
+		args = []any{err, message}
+	} else {
+		format = "%w"
+		args = []any{err}
+	}
+
+	for _, e := range more {
+		format += ": %w"
+		args = append(args, e)
+	}
+
+	err = fmt.Errorf(format, args...)
+	return err
+}

vendor/github.com/golang-jwt/jwt/v5/errors_go_other.go

@@ -0,0 +1,78 @@
+//go:build !go1.20
+// +build !go1.20
+
+package jwt
+
+import (
+	"errors"
+	"fmt"
+)
+
+// Is implements checking for multiple errors using [errors.Is], since multiple
+// error unwrapping is not possible in versions less than Go 1.20.
+func (je joinedError) Is(err error) bool {
+	for _, e := range je.errs {
+		if errors.Is(e, err) {
+			return true
+		}
+	}
+
+	return false
+}
+
+// wrappedErrors is a workaround for wrapping multiple errors in environments
+// where Go 1.20 is not available. It basically uses the already implemented
+// functionality of joinedError to handle multiple errors with supplies a
+// custom error message that is identical to the one we produce in Go 1.20 using
+// multiple %w directives.
+type wrappedErrors struct {
+	msg string
+	joinedError
+}
+
+// Error returns the stored error string
+func (we wrappedErrors) Error() string {
+	return we.msg
+}
+
+// newError creates a new error message with a detailed error message. The
+// message will be prefixed with the contents of the supplied error type.
+// Additionally, more errors, that provide more context can be supplied which
+// will be appended to the message. Since we cannot use of Go 1.20's possibility
+// to include more than one %w formatting directive in [fmt.Errorf], we have to
+// emulate that.
+//
+// For example,
+//
+//	newError("no keyfunc was provided", ErrTokenUnverifiable)
+//
+// will produce the error string
+//
+//	"token is unverifiable: no keyfunc was provided"
+func newError(message string, err error, more ...error) error {
+	// We cannot wrap multiple errors here with %w, so we have to be a little
+	// bit creative. Basically, we are using %s instead of %w to produce the
+	// same error message and then throw the result into a custom error struct.
+	var format string
+	var args []any
+	if message != "" {
+		format = "%s: %s"
+		args = []any{err, message}
+	} else {
+		format = "%s"
+		args = []any{err}
+	}
+	errs := []error{err}
+
+	for _, e := range more {
+		format += ": %s"
+		args = append(args, e)
+		errs = append(errs, e)
+	}
+
+	err = &wrappedErrors{
+		msg:         fmt.Sprintf(format, args...),
+		joinedError: joinedError{errs: errs},
+	}
+	return err
+}

vendor/github.com/golang-jwt/jwt/v5/hmac.go

@@ -6,7 +6,7 @@ import (
 	"errors"
 )
 
-// Implements the HMAC-SHA family of signing methods signing methods
+// SigningMethodHMAC implements the HMAC-SHA family of signing methods.
 // Expects key type of []byte for both signing and validation
 type SigningMethodHMAC struct {
 	Name string
@@ -45,18 +45,21 @@ func (m *SigningMethodHMAC) Alg() string {
 	return m.Name
 }
 
-// Verify the signature of HSXXX tokens.  Returns nil if the signature is valid.
-func (m *SigningMethodHMAC) Verify(signingString, signature string, key interface{}) error {
+// Verify implements token verification for the SigningMethod. Returns nil if
+// the signature is valid. Key must be []byte.
+//
+// Note it is not advised to provide a []byte which was converted from a 'human
+// readable' string using a subset of ASCII characters. To maximize entropy, you
+// should ideally be providing a []byte key which was produced from a
+// cryptographically random source, e.g. crypto/rand. Additional information
+// about this, and why we intentionally are not supporting string as a key can
+// be found on our usage guide
+// https://golang-jwt.github.io/jwt/usage/signing_methods/#signing-methods-and-key-types.
+func (m *SigningMethodHMAC) Verify(signingString string, sig []byte, key interface{}) error {
 	// Verify the key is the right type
 	keyBytes, ok := key.([]byte)
 	if !ok {
-		return ErrInvalidKeyType
-	}
-
-	// Decode signature, for comparison
-	sig, err := DecodeSegment(signature)
-	if err != nil {
-		return err
+		return newError("HMAC verify expects []byte", ErrInvalidKeyType)
 	}
 
 	// Can we use the specified hashing method?
@@ -77,19 +80,25 @@ func (m *SigningMethodHMAC) Verify(signingString, signature string, key interfac
 	return nil
 }
 
-// Implements the Sign method from SigningMethod for this signing method.
-// Key must be []byte
-func (m *SigningMethodHMAC) Sign(signingString string, key interface{}) (string, error) {
+// Sign implements token signing for the SigningMethod. Key must be []byte.
+//
+// Note it is not advised to provide a []byte which was converted from a 'human
+// readable' string using a subset of ASCII characters. To maximize entropy, you
+// should ideally be providing a []byte key which was produced from a
+// cryptographically random source, e.g. crypto/rand. Additional information
+// about this, and why we intentionally are not supporting string as a key can
+// be found on our usage guide https://golang-jwt.github.io/jwt/usage/signing_methods/.
+func (m *SigningMethodHMAC) Sign(signingString string, key interface{}) ([]byte, error) {
 	if keyBytes, ok := key.([]byte); ok {
 		if !m.Hash.Available() {
-			return "", ErrHashUnavailable
+			return nil, newError("HMAC sign expects []byte", ErrInvalidKeyType)
 		}
 
 		hasher := hmac.New(m.Hash.New, keyBytes)
 		hasher.Write([]byte(signingString))
 
-		return EncodeSegment(hasher.Sum(nil)), nil
+		return hasher.Sum(nil), nil
 	}
 
-	return "", ErrInvalidKeyType
+	return nil, ErrInvalidKeyType
 }

vendor/github.com/golang-jwt/jwt/v5/map_claims.go

@@ -0,0 +1,109 @@
+package jwt
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+// MapClaims is a claims type that uses the map[string]interface{} for JSON
+// decoding. This is the default claims type if you don't supply one
+type MapClaims map[string]interface{}
+
+// GetExpirationTime implements the Claims interface.
+func (m MapClaims) GetExpirationTime() (*NumericDate, error) {
+	return m.parseNumericDate("exp")
+}
+
+// GetNotBefore implements the Claims interface.
+func (m MapClaims) GetNotBefore() (*NumericDate, error) {
+	return m.parseNumericDate("nbf")
+}
+
+// GetIssuedAt implements the Claims interface.
+func (m MapClaims) GetIssuedAt() (*NumericDate, error) {
+	return m.parseNumericDate("iat")
+}
+
+// GetAudience implements the Claims interface.
+func (m MapClaims) GetAudience() (ClaimStrings, error) {
+	return m.parseClaimsString("aud")
+}
+
+// GetIssuer implements the Claims interface.
+func (m MapClaims) GetIssuer() (string, error) {
+	return m.parseString("iss")
+}
+
+// GetSubject implements the Claims interface.
+func (m MapClaims) GetSubject() (string, error) {
+	return m.parseString("sub")
+}
+
+// parseNumericDate tries to parse a key in the map claims type as a number
+// date. This will succeed, if the underlying type is either a [float64] or a
+// [json.Number]. Otherwise, nil will be returned.
+func (m MapClaims) parseNumericDate(key string) (*NumericDate, error) {
+	v, ok := m[key]
+	if !ok {
+		return nil, nil
+	}
+
+	switch exp := v.(type) {
+	case float64:
+		if exp == 0 {
+			return nil, nil
+		}
+
+		return newNumericDateFromSeconds(exp), nil
+	case json.Number:
+		v, _ := exp.Float64()
+
+		return newNumericDateFromSeconds(v), nil
+	}
+
+	return nil, newError(fmt.Sprintf("%s is invalid", key), ErrInvalidType)
+}
+
+// parseClaimsString tries to parse a key in the map claims type as a
+// [ClaimsStrings] type, which can either be a string or an array of string.
+func (m MapClaims) parseClaimsString(key string) (ClaimStrings, error) {
+	var cs []string
+	switch v := m[key].(type) {
+	case string:
+		cs = append(cs, v)
+	case []string:
+		cs = v
+	case []interface{}:
+		for _, a := range v {
+			vs, ok := a.(string)
+			if !ok {
+				return nil, newError(fmt.Sprintf("%s is invalid", key), ErrInvalidType)
+			}
+			cs = append(cs, vs)
+		}
+	}
+
+	return cs, nil
+}
+
+// parseString tries to parse a key in the map claims type as a [string] type.
+// If the key does not exist, an empty string is returned. If the key has the
+// wrong type, an error is returned.
+func (m MapClaims) parseString(key string) (string, error) {
+	var (
+		ok  bool
+		raw interface{}
+		iss string
+	)
+	raw, ok = m[key]
+	if !ok {
+		return "", nil
+	}
+
+	iss, ok = raw.(string)
+	if !ok {
+		return "", newError(fmt.Sprintf("%s is invalid", key), ErrInvalidType)
+	}
+
+	return iss, nil
+}

vendor/github.com/golang-jwt/jwt/v5/none.go

@@ -1,6 +1,6 @@
 package jwt
 
-// Implements the none signing method.  This is required by the spec
+// SigningMethodNone implements the none signing method.  This is required by the spec
 // but you probably should never use it.
 var SigningMethodNone *signingMethodNone
 
@@ -13,7 +13,7 @@ type unsafeNoneMagicConstant string
 
 func init() {
 	SigningMethodNone = &signingMethodNone{}
-	NoneSignatureTypeDisallowedError = NewValidationError("'none' signature type is not allowed", ValidationErrorSignatureInvalid)
+	NoneSignatureTypeDisallowedError = newError("'none' signature type is not allowed", ErrTokenUnverifiable)
 
 	RegisterSigningMethod(SigningMethodNone.Alg(), func() SigningMethod {
 		return SigningMethodNone
@@ -25,18 +25,15 @@ func (m *signingMethodNone) Alg() string {
 }
 
 // Only allow 'none' alg type if UnsafeAllowNoneSignatureType is specified as the key
-func (m *signingMethodNone) Verify(signingString, signature string, key interface{}) (err error) {
+func (m *signingMethodNone) Verify(signingString string, sig []byte, key interface{}) (err error) {
 	// Key must be UnsafeAllowNoneSignatureType to prevent accidentally
 	// accepting 'none' signing method
 	if _, ok := key.(unsafeNoneMagicConstant); !ok {
 		return NoneSignatureTypeDisallowedError
 	}
 	// If signing method is none, signature must be an empty string
-	if signature != "" {
-		return NewValidationError(
-			"'none' signing method with non-empty signature",
-			ValidationErrorSignatureInvalid,
-		)
+	if len(sig) != 0 {
+		return newError("'none' signing method with non-empty signature", ErrTokenUnverifiable)
 	}
 
 	// Accept 'none' signing method.
@@ -44,9 +41,10 @@ func (m *signingMethodNone) Verify(signingString, signature string, key interfac
 }
 
 // Only allow 'none' signing if UnsafeAllowNoneSignatureType is specified as the key
-func (m *signingMethodNone) Sign(signingString string, key interface{}) (string, error) {
+func (m *signingMethodNone) Sign(signingString string, key interface{}) ([]byte, error) {
 	if _, ok := key.(unsafeNoneMagicConstant); ok {
-		return "", nil
+		return []byte{}, nil
 	}
-	return "", NoneSignatureTypeDisallowedError
+
+	return nil, NoneSignatureTypeDisallowedError
 }

vendor/github.com/golang-jwt/jwt/v5/parser.go

@@ -0,0 +1,238 @@
+package jwt
+
+import (
+	"bytes"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+type Parser struct {
+	// If populated, only these methods will be considered valid.
+	validMethods []string
+
+	// Use JSON Number format in JSON decoder.
+	useJSONNumber bool
+
+	// Skip claims validation during token parsing.
+	skipClaimsValidation bool
+
+	validator *Validator
+
+	decodeStrict bool
+
+	decodePaddingAllowed bool
+}
+
+// NewParser creates a new Parser with the specified options
+func NewParser(options ...ParserOption) *Parser {
+	p := &Parser{
+		validator: &Validator{},
+	}
+
+	// Loop through our parsing options and apply them
+	for _, option := range options {
+		option(p)
+	}
+
+	return p
+}
+
+// Parse parses, validates, verifies the signature and returns the parsed token.
+// keyFunc will receive the parsed token and should return the key for validating.
+func (p *Parser) Parse(tokenString string, keyFunc Keyfunc) (*Token, error) {
+	return p.ParseWithClaims(tokenString, MapClaims{}, keyFunc)
+}
+
+// ParseWithClaims parses, validates, and verifies like Parse, but supplies a default object implementing the Claims
+// interface. This provides default values which can be overridden and allows a caller to use their own type, rather
+// than the default MapClaims implementation of Claims.
+//
+// Note: If you provide a custom claim implementation that embeds one of the standard claims (such as RegisteredClaims),
+// make sure that a) you either embed a non-pointer version of the claims or b) if you are using a pointer, allocate the
+// proper memory for it before passing in the overall claims, otherwise you might run into a panic.
+func (p *Parser) ParseWithClaims(tokenString string, claims Claims, keyFunc Keyfunc) (*Token, error) {
+	token, parts, err := p.ParseUnverified(tokenString, claims)
+	if err != nil {
+		return token, err
+	}
+
+	// Verify signing method is in the required set
+	if p.validMethods != nil {
+		var signingMethodValid = false
+		var alg = token.Method.Alg()
+		for _, m := range p.validMethods {
+			if m == alg {
+				signingMethodValid = true
+				break
+			}
+		}
+		if !signingMethodValid {
+			// signing method is not in the listed set
+			return token, newError(fmt.Sprintf("signing method %v is invalid", alg), ErrTokenSignatureInvalid)
+		}
+	}
+
+	// Decode signature
+	token.Signature, err = p.DecodeSegment(parts[2])
+	if err != nil {
+		return token, newError("could not base64 decode signature", ErrTokenMalformed, err)
+	}
+	text := strings.Join(parts[0:2], ".")
+
+	// Lookup key(s)
+	if keyFunc == nil {
+		// keyFunc was not provided.  short circuiting validation
+		return token, newError("no keyfunc was provided", ErrTokenUnverifiable)
+	}
+
+	got, err := keyFunc(token)
+	if err != nil {
+		return token, newError("error while executing keyfunc", ErrTokenUnverifiable, err)
+	}
+
+	switch have := got.(type) {
+	case VerificationKeySet:
+		if len(have.Keys) == 0 {
+			return token, newError("keyfunc returned empty verification key set", ErrTokenUnverifiable)
+		}
+		// Iterate through keys and verify signature, skipping the rest when a match is found.
+		// Return the last error if no match is found.
+		for _, key := range have.Keys {
+			if err = token.Method.Verify(text, token.Signature, key); err == nil {
+				break
+			}
+		}
+	default:
+		err = token.Method.Verify(text, token.Signature, have)
+	}
+	if err != nil {
+		return token, newError("", ErrTokenSignatureInvalid, err)
+	}
+
+	// Validate Claims
+	if !p.skipClaimsValidation {
+		// Make sure we have at least a default validator
+		if p.validator == nil {
+			p.validator = NewValidator()
+		}
+
+		if err := p.validator.Validate(claims); err != nil {
+			return token, newError("", ErrTokenInvalidClaims, err)
+		}
+	}
+
+	// No errors so far, token is valid.
+	token.Valid = true
+
+	return token, nil
+}
+
+// ParseUnverified parses the token but doesn't validate the signature.
+//
+// WARNING: Don't use this method unless you know what you're doing.
+//
+// It's only ever useful in cases where you know the signature is valid (since it has already
+// been or will be checked elsewhere in the stack) and you want to extract values from it.
+func (p *Parser) ParseUnverified(tokenString string, claims Claims) (token *Token, parts []string, err error) {
+	parts = strings.Split(tokenString, ".")
+	if len(parts) != 3 {
+		return nil, parts, newError("token contains an invalid number of segments", ErrTokenMalformed)
+	}
+
+	token = &Token{Raw: tokenString}
+
+	// parse Header
+	var headerBytes []byte
+	if headerBytes, err = p.DecodeSegment(parts[0]); err != nil {
+		return token, parts, newError("could not base64 decode header", ErrTokenMalformed, err)
+	}
+	if err = json.Unmarshal(headerBytes, &token.Header); err != nil {
+		return token, parts, newError("could not JSON decode header", ErrTokenMalformed, err)
+	}
+
+	// parse Claims
+	token.Claims = claims
+
+	claimBytes, err := p.DecodeSegment(parts[1])
+	if err != nil {
+		return token, parts, newError("could not base64 decode claim", ErrTokenMalformed, err)
+	}
+
+	// If `useJSONNumber` is enabled then we must use *json.Decoder to decode
+	// the claims. However, this comes with a performance penalty so only use
+	// it if we must and, otherwise, simple use json.Unmarshal.
+	if !p.useJSONNumber {
+		// JSON Unmarshal. Special case for map type to avoid weird pointer behavior.
+		if c, ok := token.Claims.(MapClaims); ok {
+			err = json.Unmarshal(claimBytes, &c)
+		} else {
+			err = json.Unmarshal(claimBytes, &claims)
+		}
+	} else {
+		dec := json.NewDecoder(bytes.NewBuffer(claimBytes))
+		dec.UseNumber()
+		// JSON Decode. Special case for map type to avoid weird pointer behavior.
+		if c, ok := token.Claims.(MapClaims); ok {
+			err = dec.Decode(&c)
+		} else {
+			err = dec.Decode(&claims)
+		}
+	}
+	if err != nil {
+		return token, parts, newError("could not JSON decode claim", ErrTokenMalformed, err)
+	}
+
+	// Lookup signature method
+	if method, ok := token.Header["alg"].(string); ok {
+		if token.Method = GetSigningMethod(method); token.Method == nil {
+			return token, parts, newError("signing method (alg) is unavailable", ErrTokenUnverifiable)
+		}
+	} else {
+		return token, parts, newError("signing method (alg) is unspecified", ErrTokenUnverifiable)
+	}
+
+	return token, parts, nil
+}
+
+// DecodeSegment decodes a JWT specific base64url encoding. This function will
+// take into account whether the [Parser] is configured with additional options,
+// such as [WithStrictDecoding] or [WithPaddingAllowed].
+func (p *Parser) DecodeSegment(seg string) ([]byte, error) {
+	encoding := base64.RawURLEncoding
+
+	if p.decodePaddingAllowed {
+		if l := len(seg) % 4; l > 0 {
+			seg += strings.Repeat("=", 4-l)
+		}
+		encoding = base64.URLEncoding
+	}
+
+	if p.decodeStrict {
+		encoding = encoding.Strict()
+	}
+	return encoding.DecodeString(seg)
+}
+
+// Parse parses, validates, verifies the signature and returns the parsed token.
+// keyFunc will receive the parsed token and should return the cryptographic key
+// for verifying the signature. The caller is strongly encouraged to set the
+// WithValidMethods option to validate the 'alg' claim in the token matches the
+// expected algorithm. For more details about the importance of validating the
+// 'alg' claim, see
+// https://auth0.com/blog/critical-vulnerabilities-in-json-web-token-libraries/
+func Parse(tokenString string, keyFunc Keyfunc, options ...ParserOption) (*Token, error) {
+	return NewParser(options...).Parse(tokenString, keyFunc)
+}
+
+// ParseWithClaims is a shortcut for NewParser().ParseWithClaims().
+//
+// Note: If you provide a custom claim implementation that embeds one of the
+// standard claims (such as RegisteredClaims), make sure that a) you either
+// embed a non-pointer version of the claims or b) if you are using a pointer,
+// allocate the proper memory for it before passing in the overall claims,
+// otherwise you might run into a panic.
+func ParseWithClaims(tokenString string, claims Claims, keyFunc Keyfunc, options ...ParserOption) (*Token, error) {
+	return NewParser(options...).ParseWithClaims(tokenString, claims, keyFunc)
+}

vendor/github.com/golang-jwt/jwt/v5/parser_option.go

@@ -0,0 +1,128 @@
+package jwt
+
+import "time"
+
+// ParserOption is used to implement functional-style options that modify the
+// behavior of the parser. To add new options, just create a function (ideally
+// beginning with With or Without) that returns an anonymous function that takes
+// a *Parser type as input and manipulates its configuration accordingly.
+type ParserOption func(*Parser)
+
+// WithValidMethods is an option to supply algorithm methods that the parser
+// will check. Only those methods will be considered valid. It is heavily
+// encouraged to use this option in order to prevent attacks such as
+// https://auth0.com/blog/critical-vulnerabilities-in-json-web-token-libraries/.
+func WithValidMethods(methods []string) ParserOption {
+	return func(p *Parser) {
+		p.validMethods = methods
+	}
+}
+
+// WithJSONNumber is an option to configure the underlying JSON parser with
+// UseNumber.
+func WithJSONNumber() ParserOption {
+	return func(p *Parser) {
+		p.useJSONNumber = true
+	}
+}
+
+// WithoutClaimsValidation is an option to disable claims validation. This
+// option should only be used if you exactly know what you are doing.
+func WithoutClaimsValidation() ParserOption {
+	return func(p *Parser) {
+		p.skipClaimsValidation = true
+	}
+}
+
+// WithLeeway returns the ParserOption for specifying the leeway window.
+func WithLeeway(leeway time.Duration) ParserOption {
+	return func(p *Parser) {
+		p.validator.leeway = leeway
+	}
+}
+
+// WithTimeFunc returns the ParserOption for specifying the time func. The
+// primary use-case for this is testing. If you are looking for a way to account
+// for clock-skew, WithLeeway should be used instead.
+func WithTimeFunc(f func() time.Time) ParserOption {
+	return func(p *Parser) {
+		p.validator.timeFunc = f
+	}
+}
+
+// WithIssuedAt returns the ParserOption to enable verification
+// of issued-at.
+func WithIssuedAt() ParserOption {
+	return func(p *Parser) {
+		p.validator.verifyIat = true
+	}
+}
+
+// WithExpirationRequired returns the ParserOption to make exp claim required.
+// By default exp claim is optional.
+func WithExpirationRequired() ParserOption {
+	return func(p *Parser) {
+		p.validator.requireExp = true
+	}
+}
+
+// WithAudience configures the validator to require the specified audience in
+// the `aud` claim. Validation will fail if the audience is not listed in the
+// token or the `aud` claim is missing.
+//
+// NOTE: While the `aud` claim is OPTIONAL in a JWT, the handling of it is
+// application-specific. Since this validation API is helping developers in
+// writing secure application, we decided to REQUIRE the existence of the claim,
+// if an audience is expected.
+func WithAudience(aud string) ParserOption {
+	return func(p *Parser) {
+		p.validator.expectedAud = aud
+	}
+}
+
+// WithIssuer configures the validator to require the specified issuer in the
+// `iss` claim. Validation will fail if a different issuer is specified in the
+// token or the `iss` claim is missing.
+//
+// NOTE: While the `iss` claim is OPTIONAL in a JWT, the handling of it is
+// application-specific. Since this validation API is helping developers in
+// writing secure application, we decided to REQUIRE the existence of the claim,
+// if an issuer is expected.
+func WithIssuer(iss string) ParserOption {
+	return func(p *Parser) {
+		p.validator.expectedIss = iss
+	}
+}
+
+// WithSubject configures the validator to require the specified subject in the
+// `sub` claim. Validation will fail if a different subject is specified in the
+// token or the `sub` claim is missing.
+//
+// NOTE: While the `sub` claim is OPTIONAL in a JWT, the handling of it is
+// application-specific. Since this validation API is helping developers in
+// writing secure application, we decided to REQUIRE the existence of the claim,
+// if a subject is expected.
+func WithSubject(sub string) ParserOption {
+	return func(p *Parser) {
+		p.validator.expectedSub = sub
+	}
+}
+
+// WithPaddingAllowed will enable the codec used for decoding JWTs to allow
+// padding. Note that the JWS RFC7515 states that the tokens will utilize a
+// Base64url encoding with no padding. Unfortunately, some implementations of
+// JWT are producing non-standard tokens, and thus require support for decoding.
+func WithPaddingAllowed() ParserOption {
+	return func(p *Parser) {
+		p.decodePaddingAllowed = true
+	}
+}
+
+// WithStrictDecoding will switch the codec used for decoding JWTs into strict
+// mode. In this mode, the decoder requires that trailing padding bits are zero,
+// as described in RFC 4648 section 3.5.
+func WithStrictDecoding() ParserOption {
+	return func(p *Parser) {
+		p.decodeStrict = true
+	}
+}

vendor/github.com/golang-jwt/jwt/v5/registered_claims.go

@@ -0,0 +1,63 @@
+package jwt
+
+// RegisteredClaims are a structured version of the JWT Claims Set,
+// restricted to Registered Claim Names, as referenced at
+// https://datatracker.ietf.org/doc/html/rfc7519#section-4.1
+//
+// This type can be used on its own, but then additional private and
+// public claims embedded in the JWT will not be parsed. The typical use-case
+// therefore is to embedded this in a user-defined claim type.
+//
+// See examples for how to use this with your own claim types.
+type RegisteredClaims struct {
+	// the `iss` (Issuer) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.1
+	Issuer string `json:"iss,omitempty"`
+
+	// the `sub` (Subject) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.2
+	Subject string `json:"sub,omitempty"`
+
+	// the `aud` (Audience) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.3
+	Audience ClaimStrings `json:"aud,omitempty"`
+
+	// the `exp` (Expiration Time) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.4
+	ExpiresAt *NumericDate `json:"exp,omitempty"`
+
+	// the `nbf` (Not Before) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.5
+	NotBefore *NumericDate `json:"nbf,omitempty"`
+
+	// the `iat` (Issued At) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.6
+	IssuedAt *NumericDate `json:"iat,omitempty"`
+
+	// the `jti` (JWT ID) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.7
+	ID string `json:"jti,omitempty"`
+}
+
+// GetExpirationTime implements the Claims interface.
+func (c RegisteredClaims) GetExpirationTime() (*NumericDate, error) {
+	return c.ExpiresAt, nil
+}
+
+// GetNotBefore implements the Claims interface.
+func (c RegisteredClaims) GetNotBefore() (*NumericDate, error) {
+	return c.NotBefore, nil
+}
+
+// GetIssuedAt implements the Claims interface.
+func (c RegisteredClaims) GetIssuedAt() (*NumericDate, error) {
+	return c.IssuedAt, nil
+}
+
+// GetAudience implements the Claims interface.
+func (c RegisteredClaims) GetAudience() (ClaimStrings, error) {
+	return c.Audience, nil
+}
+
+// GetIssuer implements the Claims interface.
+func (c RegisteredClaims) GetIssuer() (string, error) {
+	return c.Issuer, nil
+}
+
+// GetSubject implements the Claims interface.
+func (c RegisteredClaims) GetSubject() (string, error) {
+	return c.Subject, nil
+}

vendor/github.com/golang-jwt/jwt/v5/rsa.go

@@ -6,7 +6,7 @@ import (
 	"crypto/rsa"
 )
 
-// Implements the RSA family of signing methods signing methods
+// SigningMethodRSA implements the RSA family of signing methods.
 // Expects *rsa.PrivateKey for signing and *rsa.PublicKey for validation
 type SigningMethodRSA struct {
 	Name string
@@ -44,22 +44,14 @@ func (m *SigningMethodRSA) Alg() string {
 	return m.Name
 }
 
-// Implements the Verify method from SigningMethod
+// Verify implements token verification for the SigningMethod
 // For this signing method, must be an *rsa.PublicKey structure.
-func (m *SigningMethodRSA) Verify(signingString, signature string, key interface{}) error {
-	var err error
-
-	// Decode the signature
-	var sig []byte
-	if sig, err = DecodeSegment(signature); err != nil {
-		return err
-	}
-
+func (m *SigningMethodRSA) Verify(signingString string, sig []byte, key interface{}) error {
 	var rsaKey *rsa.PublicKey
 	var ok bool
 
 	if rsaKey, ok = key.(*rsa.PublicKey); !ok {
-		return ErrInvalidKeyType
+		return newError("RSA verify expects *rsa.PublicKey", ErrInvalidKeyType)
 	}
 
 	// Create hasher
@@ -73,20 +65,20 @@ func (m *SigningMethodRSA) Verify(signingString, signature string, key interface
 	return rsa.VerifyPKCS1v15(rsaKey, m.Hash, hasher.Sum(nil), sig)
 }
 
-// Implements the Sign method from SigningMethod
+// Sign implements token signing for the SigningMethod
 // For this signing method, must be an *rsa.PrivateKey structure.
-func (m *SigningMethodRSA) Sign(signingString string, key interface{}) (string, error) {
+func (m *SigningMethodRSA) Sign(signingString string, key interface{}) ([]byte, error) {
 	var rsaKey *rsa.PrivateKey
 	var ok bool
 
 	// Validate type of key
 	if rsaKey, ok = key.(*rsa.PrivateKey); !ok {
-		return "", ErrInvalidKey
+		return nil, newError("RSA sign expects *rsa.PrivateKey", ErrInvalidKeyType)
 	}
 
 	// Create the hasher
 	if !m.Hash.Available() {
-		return "", ErrHashUnavailable
+		return nil, ErrHashUnavailable
 	}
 
 	hasher := m.Hash.New()
@@ -94,8 +86,8 @@ func (m *SigningMethodRSA) Sign(signingString string, key interface{}) (string,
 
 	// Sign the string and return the encoded bytes
 	if sigBytes, err := rsa.SignPKCS1v15(rand.Reader, rsaKey, m.Hash, hasher.Sum(nil)); err == nil {
-		return EncodeSegment(sigBytes), nil
+		return sigBytes, nil
 	} else {
-		return "", err
+		return nil, err
 	}
 }

vendor/github.com/golang-jwt/jwt/v5/rsa_pss.go

@@ -1,3 +1,4 @@
+//go:build go1.4
 // +build go1.4
 
 package jwt
@@ -8,7 +9,7 @@ import (
 	"crypto/rsa"
 )
 
-// Implements the RSAPSS family of signing methods signing methods
+// SigningMethodRSAPSS implements the RSAPSS family of signing methods signing methods
 type SigningMethodRSAPSS struct {
 	*SigningMethodRSA
 	Options *rsa.PSSOptions
@@ -79,23 +80,15 @@ func init() {
 	})
 }
 
-// Implements the Verify method from SigningMethod
+// Verify implements token verification for the SigningMethod.
 // For this verify method, key must be an rsa.PublicKey struct
-func (m *SigningMethodRSAPSS) Verify(signingString, signature string, key interface{}) error {
-	var err error
-
-	// Decode the signature
-	var sig []byte
-	if sig, err = DecodeSegment(signature); err != nil {
-		return err
-	}
-
+func (m *SigningMethodRSAPSS) Verify(signingString string, sig []byte, key interface{}) error {
 	var rsaKey *rsa.PublicKey
 	switch k := key.(type) {
 	case *rsa.PublicKey:
 		rsaKey = k
 	default:
-		return ErrInvalidKey
+		return newError("RSA-PSS verify expects *rsa.PublicKey", ErrInvalidKeyType)
 	}
 
 	// Create hasher
@@ -113,21 +106,21 @@ func (m *SigningMethodRSAPSS) Verify(signingString, signature string, key interf
 	return rsa.VerifyPSS(rsaKey, m.Hash, hasher.Sum(nil), sig, opts)
 }
 
-// Implements the Sign method from SigningMethod
+// Sign implements token signing for the SigningMethod.
 // For this signing method, key must be an rsa.PrivateKey struct
-func (m *SigningMethodRSAPSS) Sign(signingString string, key interface{}) (string, error) {
+func (m *SigningMethodRSAPSS) Sign(signingString string, key interface{}) ([]byte, error) {
 	var rsaKey *rsa.PrivateKey
 
 	switch k := key.(type) {
 	case *rsa.PrivateKey:
 		rsaKey = k
 	default:
-		return "", ErrInvalidKeyType
+		return nil, newError("RSA-PSS sign expects *rsa.PrivateKey", ErrInvalidKeyType)
 	}
 
 	// Create the hasher
 	if !m.Hash.Available() {
-		return "", ErrHashUnavailable
+		return nil, ErrHashUnavailable
 	}
 
 	hasher := m.Hash.New()
@@ -135,8 +128,8 @@ func (m *SigningMethodRSAPSS) Sign(signingString string, key interface{}) (strin
 
 	// Sign the string and return the encoded bytes
 	if sigBytes, err := rsa.SignPSS(rand.Reader, rsaKey, m.Hash, hasher.Sum(nil), m.Options); err == nil {
-		return EncodeSegment(sigBytes), nil
+		return sigBytes, nil
 	} else {
-		return "", err
+		return nil, err
 	}
 }

vendor/github.com/golang-jwt/jwt/v5/rsa_utils.go

@@ -8,12 +8,12 @@ import (
 )
 
 var (
-	ErrKeyMustBePEMEncoded = errors.New("Invalid Key: Key must be a PEM encoded PKCS1 or PKCS8 key")
-	ErrNotRSAPrivateKey    = errors.New("Key is not a valid RSA private key")
-	ErrNotRSAPublicKey     = errors.New("Key is not a valid RSA public key")
+	ErrKeyMustBePEMEncoded = errors.New("invalid key: Key must be a PEM encoded PKCS1 or PKCS8 key")
+	ErrNotRSAPrivateKey    = errors.New("key is not a valid RSA private key")
+	ErrNotRSAPublicKey     = errors.New("key is not a valid RSA public key")
 )
 
-// Parse PEM encoded PKCS1 or PKCS8 private key
+// ParseRSAPrivateKeyFromPEM parses a PEM encoded PKCS1 or PKCS8 private key
 func ParseRSAPrivateKeyFromPEM(key []byte) (*rsa.PrivateKey, error) {
 	var err error
 
@@ -39,7 +39,11 @@ func ParseRSAPrivateKeyFromPEM(key []byte) (*rsa.PrivateKey, error) {
 	return pkey, nil
 }
 
-// Parse PEM encoded PKCS1 or PKCS8 private key protected with password
+// ParseRSAPrivateKeyFromPEMWithPassword parses a PEM encoded PKCS1 or PKCS8 private key protected with password
+//
+// Deprecated: This function is deprecated and should not be used anymore. It uses the deprecated x509.DecryptPEMBlock
+// function, which was deprecated since RFC 1423 is regarded insecure by design. Unfortunately, there is no alternative
+// in the Go standard library for now. See https://github.com/golang/go/issues/8860.
 func ParseRSAPrivateKeyFromPEMWithPassword(key []byte, password string) (*rsa.PrivateKey, error) {
 	var err error
 
@@ -71,7 +75,7 @@ func ParseRSAPrivateKeyFromPEMWithPassword(key []byte, password string) (*rsa.Pr
 	return pkey, nil
 }
 
-// Parse PEM encoded PKCS1 or PKCS8 public key
+// ParseRSAPublicKeyFromPEM parses a certificate or a PEM encoded PKCS1 or PKIX public key
 func ParseRSAPublicKeyFromPEM(key []byte) (*rsa.PublicKey, error) {
 	var err error
 
@@ -87,7 +91,9 @@ func ParseRSAPublicKeyFromPEM(key []byte) (*rsa.PublicKey, error) {
 		if cert, err := x509.ParseCertificate(block.Bytes); err == nil {
 			parsedKey = cert.PublicKey
 		} else {
-			return nil, err
+			if parsedKey, err = x509.ParsePKCS1PublicKey(block.Bytes); err != nil {
+				return nil, err
+			}
 		}
 	}
 

vendor/github.com/golang-jwt/jwt/v5/signing_method.go

@@ -0,0 +1,49 @@
+package jwt
+
+import (
+	"sync"
+)
+
+var signingMethods = map[string]func() SigningMethod{}
+var signingMethodLock = new(sync.RWMutex)
+
+// SigningMethod can be used add new methods for signing or verifying tokens. It
+// takes a decoded signature as an input in the Verify function and produces a
+// signature in Sign. The signature is then usually base64 encoded as part of a
+// JWT.
+type SigningMethod interface {
+	Verify(signingString string, sig []byte, key interface{}) error // Returns nil if signature is valid
+	Sign(signingString string, key interface{}) ([]byte, error)     // Returns signature or error
+	Alg() string                                                    // returns the alg identifier for this method (example: 'HS256')
+}
+
+// RegisterSigningMethod registers the "alg" name and a factory function for signing method.
+// This is typically done during init() in the method's implementation
+func RegisterSigningMethod(alg string, f func() SigningMethod) {
+	signingMethodLock.Lock()
+	defer signingMethodLock.Unlock()
+
+	signingMethods[alg] = f
+}
+
+// GetSigningMethod retrieves a signing method from an "alg" string
+func GetSigningMethod(alg string) (method SigningMethod) {
+	signingMethodLock.RLock()
+	defer signingMethodLock.RUnlock()
+
+	if methodF, ok := signingMethods[alg]; ok {
+		method = methodF()
+	}
+	return
+}
+
+// GetAlgorithms returns a list of registered "alg" names
+func GetAlgorithms() (algs []string) {
+	signingMethodLock.RLock()
+	defer signingMethodLock.RUnlock()
+
+	for alg := range signingMethods {
+		algs = append(algs, alg)
+	}
+	return
+}

vendor/github.com/golang-jwt/jwt/v5/staticcheck.conf

@@ -0,0 +1 @@
+checks = ["all", "-ST1000", "-ST1003", "-ST1016", "-ST1023"]

vendor/github.com/golang-jwt/jwt/v5/token.go

@@ -0,0 +1,100 @@
+package jwt
+
+import (
+	"crypto"
+	"encoding/base64"
+	"encoding/json"
+)
+
+// Keyfunc will be used by the Parse methods as a callback function to supply
+// the key for verification.  The function receives the parsed, but unverified
+// Token.  This allows you to use properties in the Header of the token (such as
+// `kid`) to identify which key to use.
+//
+// The returned interface{} may be a single key or a VerificationKeySet containing
+// multiple keys.
+type Keyfunc func(*Token) (interface{}, error)
+
+// VerificationKey represents a public or secret key for verifying a token's signature.
+type VerificationKey interface {
+	crypto.PublicKey | []uint8
+}
+
+// VerificationKeySet is a set of public or secret keys. It is used by the parser to verify a token.
+type VerificationKeySet struct {
+	Keys []VerificationKey
+}
+
+// Token represents a JWT Token.  Different fields will be used depending on
+// whether you're creating or parsing/verifying a token.
+type Token struct {
+	Raw       string                 // Raw contains the raw token.  Populated when you [Parse] a token
+	Method    SigningMethod          // Method is the signing method used or to be used
+	Header    map[string]interface{} // Header is the first segment of the token in decoded form
+	Claims    Claims                 // Claims is the second segment of the token in decoded form
+	Signature []byte                 // Signature is the third segment of the token in decoded form.  Populated when you Parse a token
+	Valid     bool                   // Valid specifies if the token is valid.  Populated when you Parse/Verify a token
+}
+
+// New creates a new [Token] with the specified signing method and an empty map
+// of claims. Additional options can be specified, but are currently unused.
+func New(method SigningMethod, opts ...TokenOption) *Token {
+	return NewWithClaims(method, MapClaims{}, opts...)
+}
+
+// NewWithClaims creates a new [Token] with the specified signing method and
+// claims. Additional options can be specified, but are currently unused.
+func NewWithClaims(method SigningMethod, claims Claims, opts ...TokenOption) *Token {
+	return &Token{
+		Header: map[string]interface{}{
+			"typ": "JWT",
+			"alg": method.Alg(),
+		},
+		Claims: claims,
+		Method: method,
+	}
+}
+
+// SignedString creates and returns a complete, signed JWT. The token is signed
+// using the SigningMethod specified in the token. Please refer to
+// https://golang-jwt.github.io/jwt/usage/signing_methods/#signing-methods-and-key-types
+// for an overview of the different signing methods and their respective key
+// types.
+func (t *Token) SignedString(key interface{}) (string, error) {
+	sstr, err := t.SigningString()
+	if err != nil {
+		return "", err
+	}
+
+	sig, err := t.Method.Sign(sstr, key)
+	if err != nil {
+		return "", err
+	}
+
+	return sstr + "." + t.EncodeSegment(sig), nil
+}
+
+// SigningString generates the signing string.  This is the most expensive part
+// of the whole deal.  Unless you need this for something special, just go
+// straight for the SignedString.
+func (t *Token) SigningString() (string, error) {
+	h, err := json.Marshal(t.Header)
+	if err != nil {
+		return "", err
+	}
+
+	c, err := json.Marshal(t.Claims)
+	if err != nil {
+		return "", err
+	}
+
+	return t.EncodeSegment(h) + "." + t.EncodeSegment(c), nil
+}
+
+// EncodeSegment encodes a JWT specific base64url encoding with padding
+// stripped. In the future, this function might take into account a
+// [TokenOption]. Therefore, this function exists as a method of [Token], rather
+// than a global function.
+func (*Token) EncodeSegment(seg []byte) string {
+	return base64.RawURLEncoding.EncodeToString(seg)
+}

vendor/github.com/golang-jwt/jwt/v5/token_option.go

@@ -0,0 +1,5 @@
+package jwt
+
+// TokenOption is a reserved type, which provides some forward compatibility,
+// if we ever want to introduce token creation-related options.
+type TokenOption func(*Token)

vendor/github.com/golang-jwt/jwt/v5/types.go

@@ -0,0 +1,149 @@
+package jwt
+
+import (
+	"encoding/json"
+	"fmt"
+	"math"
+	"strconv"
+	"time"
+)
+
+// TimePrecision sets the precision of times and dates within this library. This
+// has an influence on the precision of times when comparing expiry or other
+// related time fields. Furthermore, it is also the precision of times when
+// serializing.
+//
+// For backwards compatibility the default precision is set to seconds, so that
+// no fractional timestamps are generated.
+var TimePrecision = time.Second
+
+// MarshalSingleStringAsArray modifies the behavior of the ClaimStrings type,
+// especially its MarshalJSON function.
+//
+// If it is set to true (the default), it will always serialize the type as an
+// array of strings, even if it just contains one element, defaulting to the
+// behavior of the underlying []string. If it is set to false, it will serialize
+// to a single string, if it contains one element. Otherwise, it will serialize
+// to an array of strings.
+var MarshalSingleStringAsArray = true
+
+// NumericDate represents a JSON numeric date value, as referenced at
+// https://datatracker.ietf.org/doc/html/rfc7519#section-2.
+type NumericDate struct {
+	time.Time
+}
+
+// NewNumericDate constructs a new *NumericDate from a standard library time.Time struct.
+// It will truncate the timestamp according to the precision specified in TimePrecision.
+func NewNumericDate(t time.Time) *NumericDate {
+	return &NumericDate{t.Truncate(TimePrecision)}
+}
+
+// newNumericDateFromSeconds creates a new *NumericDate out of a float64 representing a
+// UNIX epoch with the float fraction representing non-integer seconds.
+func newNumericDateFromSeconds(f float64) *NumericDate {
+	round, frac := math.Modf(f)
+	return NewNumericDate(time.Unix(int64(round), int64(frac*1e9)))
+}
+
+// MarshalJSON is an implementation of the json.RawMessage interface and serializes the UNIX epoch
+// represented in NumericDate to a byte array, using the precision specified in TimePrecision.
+func (date NumericDate) MarshalJSON() (b []byte, err error) {
+	var prec int
+	if TimePrecision < time.Second {
+		prec = int(math.Log10(float64(time.Second) / float64(TimePrecision)))
+	}
+	truncatedDate := date.Truncate(TimePrecision)
+
+	// For very large timestamps, UnixNano would overflow an int64, but this
+	// function requires nanosecond level precision, so we have to use the
+	// following technique to get round the issue:
+	//
+	// 1. Take the normal unix timestamp to form the whole number part of the
+	//    output,
+	// 2. Take the result of the Nanosecond function, which returns the offset
+	//    within the second of the particular unix time instance, to form the
+	//    decimal part of the output
+	// 3. Concatenate them to produce the final result
+	seconds := strconv.FormatInt(truncatedDate.Unix(), 10)
+	nanosecondsOffset := strconv.FormatFloat(float64(truncatedDate.Nanosecond())/float64(time.Second), 'f', prec, 64)
+
+	output := append([]byte(seconds), []byte(nanosecondsOffset)[1:]...)
+
+	return output, nil
+}
+
+// UnmarshalJSON is an implementation of the json.RawMessage interface and
+// deserializes a [NumericDate] from a JSON representation, i.e. a
+// [json.Number]. This number represents an UNIX epoch with either integer or
+// non-integer seconds.
+func (date *NumericDate) UnmarshalJSON(b []byte) (err error) {
+	var (
+		number json.Number
+		f      float64
+	)
+
+	if err = json.Unmarshal(b, &number); err != nil {
+		return fmt.Errorf("could not parse NumericData: %w", err)
+	}
+
+	if f, err = number.Float64(); err != nil {
+		return fmt.Errorf("could not convert json number value to float: %w", err)
+	}
+
+	n := newNumericDateFromSeconds(f)
+	*date = *n
+
+	return nil
+}
+
+// ClaimStrings is basically just a slice of strings, but it can be either
+// serialized from a string array or just a string. This type is necessary,
+// since the "aud" claim can either be a single string or an array.
+type ClaimStrings []string
+
+func (s *ClaimStrings) UnmarshalJSON(data []byte) (err error) {
+	var value interface{}
+
+	if err = json.Unmarshal(data, &value); err != nil {
+		return err
+	}
+
+	var aud []string
+
+	switch v := value.(type) {
+	case string:
+		aud = append(aud, v)
+	case []string:
+		aud = ClaimStrings(v)
+	case []interface{}:
+		for _, vv := range v {
+			vs, ok := vv.(string)
+			if !ok {
+				return ErrInvalidType
+			}
+			aud = append(aud, vs)
+		}
+	case nil:
+		return nil
+	default:
+		return ErrInvalidType
+	}
+
+	*s = aud
+
+	return
+}
+
+func (s ClaimStrings) MarshalJSON() (b []byte, err error) {
+	// This handles a special case in the JWT RFC. If the string array, e.g.
+	// used by the "aud" field, only contains one element, it MAY be serialized
+	// as a single string. This may or may not be desired based on the ecosystem
+	// of other JWT library used, so we make it configurable by the variable
+	// MarshalSingleStringAsArray.
+	if len(s) == 1 && !MarshalSingleStringAsArray {
+		return json.Marshal(s[0])
+	}
+
+	return json.Marshal([]string(s))
+}

vendor/github.com/golang-jwt/jwt/v5/validator.go

@@ -0,0 +1,316 @@
+package jwt
+
+import (
+	"crypto/subtle"
+	"fmt"
+	"time"
+)
+
+// ClaimsValidator is an interface that can be implemented by custom claims who
+// wish to execute any additional claims validation based on
+// application-specific logic. The Validate function is then executed in
+// addition to the regular claims validation and any error returned is appended
+// to the final validation result.
+//
+//	type MyCustomClaims struct {
+//	    Foo string `json:"foo"`
+//	    jwt.RegisteredClaims
+//	}
+//
+//	func (m MyCustomClaims) Validate() error {
+//	    if m.Foo != "bar" {
+//	        return errors.New("must be foobar")
+//	    }
+//	    return nil
+//	}
+type ClaimsValidator interface {
+	Claims
+	Validate() error
+}
+
+// Validator is the core of the new Validation API. It is automatically used by
+// a [Parser] during parsing and can be modified with various parser options.
+//
+// The [NewValidator] function should be used to create an instance of this
+// struct.
+type Validator struct {
+	// leeway is an optional leeway that can be provided to account for clock skew.
+	leeway time.Duration
+
+	// timeFunc is used to supply the current time that is needed for
+	// validation. If unspecified, this defaults to time.Now.
+	timeFunc func() time.Time
+
+	// requireExp specifies whether the exp claim is required
+	requireExp bool
+
+	// verifyIat specifies whether the iat (Issued At) claim will be verified.
+	// According to https://www.rfc-editor.org/rfc/rfc7519#section-4.1.6 this
+	// only specifies the age of the token, but no validation check is
+	// necessary. However, if wanted, it can be checked if the iat is
+	// unrealistic, i.e., in the future.
+	verifyIat bool
+
+	// expectedAud contains the audience this token expects. Supplying an empty
+	// string will disable aud checking.
+	expectedAud string
+
+	// expectedIss contains the issuer this token expects. Supplying an empty
+	// string will disable iss checking.
+	expectedIss string
+
+	// expectedSub contains the subject this token expects. Supplying an empty
+	// string will disable sub checking.
+	expectedSub string
+}
+
+// NewValidator can be used to create a stand-alone validator with the supplied
+// options. This validator can then be used to validate already parsed claims.
+//
+// Note: Under normal circumstances, explicitly creating a validator is not
+// needed and can potentially be dangerous; instead functions of the [Parser]
+// class should be used.
+//
+// The [Validator] is only checking the *validity* of the claims, such as its
+// expiration time, but it does NOT perform *signature verification* of the
+// token.
+func NewValidator(opts ...ParserOption) *Validator {
+	p := NewParser(opts...)
+	return p.validator
+}
+
+// Validate validates the given claims. It will also perform any custom
+// validation if claims implements the [ClaimsValidator] interface.
+//
+// Note: It will NOT perform any *signature verification* on the token that
+// contains the claims and expects that the [Claim] was already successfully
+// verified.
+func (v *Validator) Validate(claims Claims) error {
+	var (
+		now  time.Time
+		errs []error = make([]error, 0, 6)
+		err  error
+	)
+
+	// Check, if we have a time func
+	if v.timeFunc != nil {
+		now = v.timeFunc()
+	} else {
+		now = time.Now()
+	}
+
+	// We always need to check the expiration time, but usage of the claim
+	// itself is OPTIONAL by default. requireExp overrides this behavior
+	// and makes the exp claim mandatory.
+	if err = v.verifyExpiresAt(claims, now, v.requireExp); err != nil {
+		errs = append(errs, err)
+	}
+
+	// We always need to check not-before, but usage of the claim itself is
+	// OPTIONAL.
+	if err = v.verifyNotBefore(claims, now, false); err != nil {
+		errs = append(errs, err)
+	}
+
+	// Check issued-at if the option is enabled
+	if v.verifyIat {
+		if err = v.verifyIssuedAt(claims, now, false); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	// If we have an expected audience, we also require the audience claim
+	if v.expectedAud != "" {
+		if err = v.verifyAudience(claims, v.expectedAud, true); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	// If we have an expected issuer, we also require the issuer claim
+	if v.expectedIss != "" {
+		if err = v.verifyIssuer(claims, v.expectedIss, true); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	// If we have an expected subject, we also require the subject claim
+	if v.expectedSub != "" {
+		if err = v.verifySubject(claims, v.expectedSub, true); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	// Finally, we want to give the claim itself some possibility to do some
+	// additional custom validation based on a custom Validate function.
+	cvt, ok := claims.(ClaimsValidator)
+	if ok {
+		if err := cvt.Validate(); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	if len(errs) == 0 {
+		return nil
+	}
+
+	return joinErrors(errs...)
+}
+
+// verifyExpiresAt compares the exp claim in claims against cmp. This function
+// will succeed if cmp < exp. Additional leeway is taken into account.
+//
+// If exp is not set, it will succeed if the claim is not required,
+// otherwise ErrTokenRequiredClaimMissing will be returned.
+//
+// Additionally, if any error occurs while retrieving the claim, e.g., when its
+// the wrong type, an ErrTokenUnverifiable error will be returned.
+func (v *Validator) verifyExpiresAt(claims Claims, cmp time.Time, required bool) error {
+	exp, err := claims.GetExpirationTime()
+	if err != nil {
+		return err
+	}
+
+	if exp == nil {
+		return errorIfRequired(required, "exp")
+	}
+
+	return errorIfFalse(cmp.Before((exp.Time).Add(+v.leeway)), ErrTokenExpired)
+}
+
+// verifyIssuedAt compares the iat claim in claims against cmp. This function
+// will succeed if cmp >= iat. Additional leeway is taken into account.
+//
+// If iat is not set, it will succeed if the claim is not required,
+// otherwise ErrTokenRequiredClaimMissing will be returned.
+//
+// Additionally, if any error occurs while retrieving the claim, e.g., when its
+// the wrong type, an ErrTokenUnverifiable error will be returned.
+func (v *Validator) verifyIssuedAt(claims Claims, cmp time.Time, required bool) error {
+	iat, err := claims.GetIssuedAt()
+	if err != nil {
+		return err
+	}
+
+	if iat == nil {
+		return errorIfRequired(required, "iat")
+	}
+
+	return errorIfFalse(!cmp.Before(iat.Add(-v.leeway)), ErrTokenUsedBeforeIssued)
+}
+
+// verifyNotBefore compares the nbf claim in claims against cmp. This function
+// will return true if cmp >= nbf. Additional leeway is taken into account.
+//
+// If nbf is not set, it will succeed if the claim is not required,
+// otherwise ErrTokenRequiredClaimMissing will be returned.
+//
+// Additionally, if any error occurs while retrieving the claim, e.g., when its
+// the wrong type, an ErrTokenUnverifiable error will be returned.
+func (v *Validator) verifyNotBefore(claims Claims, cmp time.Time, required bool) error {
+	nbf, err := claims.GetNotBefore()
+	if err != nil {
+		return err
+	}
+
+	if nbf == nil {
+		return errorIfRequired(required, "nbf")
+	}
+
+	return errorIfFalse(!cmp.Before(nbf.Add(-v.leeway)), ErrTokenNotValidYet)
+}
+
+// verifyAudience compares the aud claim against cmp.
+//
+// If aud is not set or an empty list, it will succeed if the claim is not required,
+// otherwise ErrTokenRequiredClaimMissing will be returned.
+//
+// Additionally, if any error occurs while retrieving the claim, e.g., when its
+// the wrong type, an ErrTokenUnverifiable error will be returned.
+func (v *Validator) verifyAudience(claims Claims, cmp string, required bool) error {
+	aud, err := claims.GetAudience()
+	if err != nil {
+		return err
+	}
+
+	if len(aud) == 0 {
+		return errorIfRequired(required, "aud")
+	}
+
+	// use a var here to keep constant time compare when looping over a number of claims
+	result := false
+
+	var stringClaims string
+	for _, a := range aud {
+		if subtle.ConstantTimeCompare([]byte(a), []byte(cmp)) != 0 {
+			result = true
+		}
+		stringClaims = stringClaims + a
+	}
+
+	// case where "" is sent in one or many aud claims
+	if stringClaims == "" {
+		return errorIfRequired(required, "aud")
+	}
+
+	return errorIfFalse(result, ErrTokenInvalidAudience)
+}
+
+// verifyIssuer compares the iss claim in claims against cmp.
+//
+// If iss is not set, it will succeed if the claim is not required,
+// otherwise ErrTokenRequiredClaimMissing will be returned.
+//
+// Additionally, if any error occurs while retrieving the claim, e.g., when its
+// the wrong type, an ErrTokenUnverifiable error will be returned.
+func (v *Validator) verifyIssuer(claims Claims, cmp string, required bool) error {
+	iss, err := claims.GetIssuer()
+	if err != nil {
+		return err
+	}
+
+	if iss == "" {
+		return errorIfRequired(required, "iss")
+	}
+
+	return errorIfFalse(iss == cmp, ErrTokenInvalidIssuer)
+}
+
+// verifySubject compares the sub claim against cmp.
+//
+// If sub is not set, it will succeed if the claim is not required,
+// otherwise ErrTokenRequiredClaimMissing will be returned.
+//
+// Additionally, if any error occurs while retrieving the claim, e.g., when its
+// the wrong type, an ErrTokenUnverifiable error will be returned.
+func (v *Validator) verifySubject(claims Claims, cmp string, required bool) error {
+	sub, err := claims.GetSubject()
+	if err != nil {
+		return err
+	}
+
+	if sub == "" {
+		return errorIfRequired(required, "sub")
+	}
+
+	return errorIfFalse(sub == cmp, ErrTokenInvalidSubject)
+}
+
+// errorIfFalse returns the error specified in err, if the value is true.
+// Otherwise, nil is returned.
+func errorIfFalse(value bool, err error) error {
+	if value {
+		return nil
+	} else {
+		return err
+	}
+}
+
+// errorIfRequired returns an ErrTokenRequiredClaimMissing error if required is
+// true. Otherwise, nil is returned.
+func errorIfRequired(required bool, claim string) error {
+	if required {
+		return newError(fmt.Sprintf("%s claim is required", claim), ErrTokenRequiredClaimMissing)
+	} else {
+		return nil
+	}
+}

vendor/modules.txt

@@ -16,7 +16,7 @@ github.com/ergochat/confusables
 # github.com/ergochat/go-ident v0.0.0-20230911071154-8c30606d6881
 ## explicit; go 1.18
 github.com/ergochat/go-ident
-# github.com/ergochat/irc-go v0.4.0
+# github.com/ergochat/irc-go v0.5.0-rc1
 ## explicit; go 1.15
 github.com/ergochat/irc-go/ircfmt
 github.com/ergochat/irc-go/ircmsg
@@ -30,9 +30,9 @@ github.com/go-sql-driver/mysql
 # github.com/gofrs/flock v0.8.1
 ## explicit
 github.com/gofrs/flock
-# github.com/golang-jwt/jwt v3.2.2+incompatible
-## explicit
-github.com/golang-jwt/jwt
+# github.com/golang-jwt/jwt/v5 v5.2.0
+## explicit; go 1.18
+github.com/golang-jwt/jwt/v5
 # github.com/gorilla/websocket v1.4.2 => github.com/ergochat/websocket v1.4.2-oragono1
 ## explicit; go 1.12
 github.com/gorilla/websocket