keel/jwt/keyfunc.go
2021-11-17 11:36:36 +01:00

26 lines
806 B
Go

package jwt
import (
"github.com/golang-jwt/jwt"
"github.com/pkg/errors"
)
func DefaultKeyFunc(key Key, deprecatedKeys map[string]Key) jwt.Keyfunc {
return func(token *jwt.Token) (interface{}, error) {
if token.Method.Alg() != jwt.SigningMethodRS256.Name {
return nil, errors.New("unexpected jwt signing method: " + token.Method.Alg())
}
if kid, ok := token.Header["kid"]; !ok {
return nil, errors.New("missing key identifier")
} else if kidString, ok := kid.(string); !ok {
return nil, errors.New("invalid key identifier type")
} else if oldKey, ok := deprecatedKeys[kidString]; ok {
return oldKey.Public, nil
} else if kidString == key.ID {
return key.Public, nil
} else {
return nil, errors.New("unknown key identifier: " + kidString + " (" + key.ID + ")")
}
}
}