bench-forgejo/vendor/github.com/dgrijalva/jwt-go/hmac.go
Cherrg 86750325c7 workaround broken drone build (#7362)
* workaround broken swagger

only master brach is not working, latest release seems to work

Signed-off-by: Michael Gnehr <michael@gnehr.de>

* make vendor

Signed-off-by: Michael Gnehr <michael@gnehr.de>

* Don't export GO111MODULE

* set go-swagger to fixed release version

mentioned here: https://github.com/go-gitea/gitea/pull/7362#discussion_r300831537

Signed-off-by: Michael Gnehr <michael@gnehr.de>
2019-07-06 16:16:43 +01:00

95 lines
2.4 KiB
Go

package jwt
import (
"crypto"
"crypto/hmac"
"errors"
)
// Implements the HMAC-SHA family of signing methods signing methods
// Expects key type of []byte for both signing and validation
type SigningMethodHMAC struct {
Name string
Hash crypto.Hash
}
// Specific instances for HS256 and company
var (
SigningMethodHS256 *SigningMethodHMAC
SigningMethodHS384 *SigningMethodHMAC
SigningMethodHS512 *SigningMethodHMAC
ErrSignatureInvalid = errors.New("signature is invalid")
)
func init() {
// HS256
SigningMethodHS256 = &SigningMethodHMAC{"HS256", crypto.SHA256}
RegisterSigningMethod(SigningMethodHS256.Alg(), func() SigningMethod {
return SigningMethodHS256
})
// HS384
SigningMethodHS384 = &SigningMethodHMAC{"HS384", crypto.SHA384}
RegisterSigningMethod(SigningMethodHS384.Alg(), func() SigningMethod {
return SigningMethodHS384
})
// HS512
SigningMethodHS512 = &SigningMethodHMAC{"HS512", crypto.SHA512}
RegisterSigningMethod(SigningMethodHS512.Alg(), func() SigningMethod {
return SigningMethodHS512
})
}
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 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
}
// Can we use the specified hashing method?
if !m.Hash.Available() {
return ErrHashUnavailable
}
// This signing method is symmetric, so we validate the signature
// by reproducing the signature from the signing string and key, then
// comparing that against the provided signature.
hasher := hmac.New(m.Hash.New, keyBytes)
hasher.Write([]byte(signingString))
if !hmac.Equal(sig, hasher.Sum(nil)) {
return ErrSignatureInvalid
}
// No validation errors. Signature is good.
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) {
if keyBytes, ok := key.([]byte); ok {
if !m.Hash.Available() {
return "", ErrHashUnavailable
}
hasher := hmac.New(m.Hash.New, keyBytes)
hasher.Write([]byte(signingString))
return EncodeSegment(hasher.Sum(nil)), nil
}
return "", ErrInvalidKeyType
}