diff options
Diffstat (limited to 'vendor/github.com/golang-jwt/jwt/v5/parser.go')
| -rw-r--r-- | vendor/github.com/golang-jwt/jwt/v5/parser.go | 36 |
1 files changed, 33 insertions, 3 deletions
diff --git a/vendor/github.com/golang-jwt/jwt/v5/parser.go b/vendor/github.com/golang-jwt/jwt/v5/parser.go index ecf99af78..054c7eb6f 100644 --- a/vendor/github.com/golang-jwt/jwt/v5/parser.go +++ b/vendor/github.com/golang-jwt/jwt/v5/parser.go @@ -8,6 +8,8 @@ import ( "strings" ) +const tokenDelimiter = "." + type Parser struct { // If populated, only these methods will be considered valid. validMethods []string @@ -136,9 +138,10 @@ func (p *Parser) ParseWithClaims(tokenString string, claims Claims, keyFunc Keyf // 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) + var ok bool + parts, ok = splitToken(tokenString) + if !ok { + return nil, nil, newError("token contains an invalid number of segments", ErrTokenMalformed) } token = &Token{Raw: tokenString} @@ -196,6 +199,33 @@ func (p *Parser) ParseUnverified(tokenString string, claims Claims) (token *Toke return token, parts, nil } +// splitToken splits a token string into three parts: header, claims, and signature. It will only +// return true if the token contains exactly two delimiters and three parts. In all other cases, it +// will return nil parts and false. +func splitToken(token string) ([]string, bool) { + parts := make([]string, 3) + header, remain, ok := strings.Cut(token, tokenDelimiter) + if !ok { + return nil, false + } + parts[0] = header + claims, remain, ok := strings.Cut(remain, tokenDelimiter) + if !ok { + return nil, false + } + parts[1] = claims + // One more cut to ensure the signature is the last part of the token and there are no more + // delimiters. This avoids an issue where malicious input could contain additional delimiters + // causing unecessary overhead parsing tokens. + signature, _, unexpected := strings.Cut(remain, tokenDelimiter) + if unexpected { + return nil, false + } + parts[2] = signature + + return parts, true +} + // 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]. |