path: root/vendor/github.com/dgrijalva/jwt-go/rsa_utils.go

package jwt

import (
    "crypto/rsa"
    "crypto/x509"
    "encoding/pem"
    "errors"
)

var (
    ErrKeyMustBePEMEncoded = errors.New("Invalid Key: Key must be PEM encoded PKCS1 or PKCS8 private key")
    ErrNotRSAPrivateKey    = errors.New("Key is not a valid RSA private key")
    ErrNotRSAPublicKey     = errors.New("Key is not a valid RSA public key")
)

// Parse PEM encoded PKCS1 or PKCS8 private key
func ParseRSAPrivateKeyFromPEM(key []byte) (*rsa.PrivateKey, error) {
    var err error

    // Parse PEM block
    var block *pem.Block
    if block, _ = pem.Decode(key); block == nil {
        return nil, ErrKeyMustBePEMEncoded
    }

    var parsedKey interface{}
    if parsedKey, err = x509.ParsePKCS1PrivateKey(block.Bytes); err != nil {
        if parsedKey, err = x509.ParsePKCS8PrivateKey(block.Bytes); err != nil {
            return nil, err
        }
    }

    var pkey *rsa.PrivateKey
    var ok bool
    if pkey, ok = parsedKey.(*rsa.PrivateKey); !ok {
        return nil, ErrNotRSAPrivateKey
    }

    return pkey, nil
}

// Parse PEM encoded PKCS1 or PKCS8 public key
func ParseRSAPublicKeyFromPEM(key []byte) (*rsa.PublicKey, error) {
    var err error

    // Parse PEM block
    var block *pem.Block
    if block, _ = pem.Decode(key); block == nil {
        return nil, ErrKeyMustBePEMEncoded
    }

    // Parse the key
    var parsedKey interface{}
    if parsedKey, err = x509.ParsePKIXPublicKey(block.Bytes); err != nil {
        if cert, err := x509.ParseCertificate(block.Bytes); err == nil {
            parsedKey = cert.PublicKey
        } else {
            return nil, err
        }
    }

    var pkey *rsa.PublicKey
    var ok bool
    if pkey, ok = parsedKey.(*rsa.PublicKey); !ok {
        return nil, ErrNotRSAPublicKey
    }

    return pkey, nil
}