go-sample-webpage/vendor/github.com/lestrrat-go/jwx/jws/signer.go
2021-11-04 02:14:51 +01:00

68 lines
1.9 KiB
Go

package jws
import (
"github.com/lestrrat-go/jwx/jwa"
"github.com/pkg/errors"
)
type SignerFactory interface {
Create() (Signer, error)
}
type SignerFactoryFn func() (Signer, error)
func (fn SignerFactoryFn) Create() (Signer, error) {
return fn()
}
var signerDB map[jwa.SignatureAlgorithm]SignerFactory
// RegisterSigner is used to register a factory object that creates
// Signer objects based on the given algorithm.
//
// For example, if you would like to provide a custom signer for
// jwa.EdDSA, use this function to register a `SignerFactory`
// (probably in your `init()`)
func RegisterSigner(alg jwa.SignatureAlgorithm, f SignerFactory) {
signerDB[alg] = f
}
func init() {
signerDB = make(map[jwa.SignatureAlgorithm]SignerFactory)
for _, alg := range []jwa.SignatureAlgorithm{jwa.RS256, jwa.RS384, jwa.RS512, jwa.PS256, jwa.PS384, jwa.PS512} {
RegisterSigner(alg, func(alg jwa.SignatureAlgorithm) SignerFactory {
return SignerFactoryFn(func() (Signer, error) {
return newRSASigner(alg), nil
})
}(alg))
}
for _, alg := range []jwa.SignatureAlgorithm{jwa.ES256, jwa.ES384, jwa.ES512, jwa.ES256K} {
RegisterSigner(alg, func(alg jwa.SignatureAlgorithm) SignerFactory {
return SignerFactoryFn(func() (Signer, error) {
return newECDSASigner(alg), nil
})
}(alg))
}
for _, alg := range []jwa.SignatureAlgorithm{jwa.HS256, jwa.HS384, jwa.HS512} {
RegisterSigner(alg, func(alg jwa.SignatureAlgorithm) SignerFactory {
return SignerFactoryFn(func() (Signer, error) {
return newHMACSigner(alg), nil
})
}(alg))
}
RegisterSigner(jwa.EdDSA, SignerFactoryFn(func() (Signer, error) {
return newEdDSASigner(), nil
}))
}
// NewSigner creates a signer that signs payloads using the given signature algorithm.
func NewSigner(alg jwa.SignatureAlgorithm) (Signer, error) {
f, ok := signerDB[alg]
if ok {
return f.Create()
}
return nil, errors.Errorf(`unsupported signature algorithm "%s"`, alg)
}