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-rw-r--r--vendor/github.com/golang-jwt/jwt/v5/parser.go238
1 files changed, 238 insertions, 0 deletions
diff --git a/vendor/github.com/golang-jwt/jwt/v5/parser.go b/vendor/github.com/golang-jwt/jwt/v5/parser.go
new file mode 100644
index 000000000..ecf99af78
--- /dev/null
+++ b/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)
+}