open-nomad/vendor/github.com/dgrijalva/jwt-go/token.go
Seth Hoenig 435c0d9fc8 deps: Switch to Go modules for dependency management
This PR switches the Nomad repository from using govendor to Go modules
for managing dependencies. Aspects of the Nomad workflow remain pretty
much the same. The usual Makefile targets should continue to work as
they always did. The API submodule simply defers to the parent Nomad
version on the repository, keeping the semantics of API versioning that
currently exists.
2020-06-02 14:30:36 -05:00

109 lines
3.3 KiB
Go

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 strings.TrimRight(base64.URLEncoding.EncodeToString(seg), "=")
}
// Decode JWT specific base64url encoding with padding stripped
func DecodeSegment(seg string) ([]byte, error) {
if l := len(seg) % 4; l > 0 {
seg += strings.Repeat("=", 4-l)
}
return base64.URLEncoding.DecodeString(seg)
}