Problem with JWT signing: "The provided key did not have the expected PEM headers/footers"

[alfitriv]

Hello thank you so much for creating this library. I have been working on a problem where I was not able to have success with signing my JWT. The following is my code:

    let teamID = some value
    let keyID = some value
    let authToken = """
                -----BEGIN PRIVATE KEY-----
                MIIEvQIBADANBgkqhkiG9w0BAQEFAASCBKcwggSjAgEAAoIBAQCoknaik3X9AwXf
                1nb/BfHlR4RBcij+Ri2RzxZfdcTuhcIL4XLrgwaz/Skx3R/UjU3eoxneBjcGeA7X
                QX75aXMS2FKrfQEJ6mp9AVQTowPC5VkAp8L8vk/cBrckZFHQsm9bHnLirJ6LYhWK
                sLbvgpJo+P4OMG4P/GeQVwaWwLxaZNSs0sEjVRuy0vbWCO4jJwnmZpPMxU0sRCRN
                xod3n6DJ0XhwCP/CxhlFVHjoM/nX/HGlPWkwG05BFBH4J9Zy4SNNNg6CDjIsl56R
                2Fu8d/RHtIB/UPhIEoV6t5rWkJx4SP76OwjiXl9IGiDWpb6uu2/OQctZRBezxvCZ
                O4lgzKFXAgMBAAECggEAYK4XsmhmbCTWsqka+GqdcIVS2gIydpsjOZQO3dL6jl5S
                i2PS+DXem04f2URcJBiix4S9qjPgTSqAQH6E52DOKcm9qDL6bIhwaJ9hbB27Y4UM
                Ra7xyukPfj6vvQR4U/xyl0zgURb1mzU266MsWDOH6wKbGuI1zZ9SelsfIUkK/cAV
                s6Ao4kzCCQWZMQ/GkYxtQXg/tdPtI2Ueexon0Xtr4bc50XefEFvpKNi3ZqX7fRHV
                e2bvnzKH6TN6DlEBruIdRwLsfmFXMIXU98D1OYokaaeVeHH5iZ2nXrlGGw72RfcQ
                awrEHvMTTUhzg5LnMw30Smq1ogPanhLtbofPqIQJwQKBgQDfxKZ7lFle+tiMEKmU
                87uiRavAHrmQNipqBcbtadJqqQtvGOCxwSg9phh2YnwxRSyw1oBpg4ogvg1QbhqV
                UNfB8b/M2kpPRpGZpjCvi6En8GzK6K4e/UQJ4i0l7tPT9tt3TynbMwb3xFcEnFEX
                IxfcWnlbC5tm5Sea6b4BzwK84QKBgQDA2nvqHNsqU9HyCX61R5Bo2QLnsI4CgUBk
                z2hhc4bteb//mKCWeVvPNRu9AFhNEJzix0/EEkCVhbpIKE1DUCzBPWI/4CkH1bRc
                RBE7/7I3pcMBbV22OdGoISmUf6IFZSyQuBoShLDBH3CVmqdmto9b5nwYaTgdycvt
                xpyQvdKtNwKBgHFzF2EyXnlcPqwMyp29URU9s41NRpGKFMj6MtgtvcPb/vMNruYQ
                Y2GWM3LaDdNBGh5yMlrMmRxunvt3Rz0K5sjq025+AgzdX3aCHs7xwPwp1k6t15HY
                oEVOictgob8mujBsT3FWFqNJxUCOLELJxRAwQrTZVqm9Zu4Qsgfit6WhAoGBAKWx
                UbOUNU0JlSDBvaacpNsgUFmlnG1UhXHXrVPFAVE5QJeml5qRDCtb8sgQ6szTkCdb
                nRHVqL2Olrz2O2OxF7KzPZ2pxzbfCkYXiUMmbgVXmtK4F0LALHyqeWIHwrml8oMo
                WeY9MOvMSluO83LRORx5S3dht4AIZ/iTouLM5JxDAoGAcAnam49TeCFZuOu5/QCb
                GYyAntOQL/nunSbuHoNvC+bBrcUX2BfDkalkzlm/YRJgmqSQ7Ih3fbp4i5NCVtpM
                1dafoyed5UqY0F7Vou7JJE57tlKieKPhQOMTSl2Q5WMvby+owRb0Sx325xQvoslH
                QM9+y6wy6YMdNweC+JkcZVo=
                -----END PRIVATE KEY-----
                """


    func generateToken() {
        let myHeader = Header(kid: keyID)
        let urlString = "https://www.googleapis.com/oauth2/v4/token"
        let claims = JWTClaims(iss: teamID, iat: Date(), exp: Date() + 3.0, scope: "devstorage.read_write", aud: urlString)
        var jwt = SwiftJWT.JWT(header: myHeader, claims: claims)
        
        
        guard let tokenData = authToken.data(using: .utf8)?.base64EncodedData() else {
            return
        }
        
        var jwtSigner = JWTSigner.rs256(privateKey: tokenData)
        
        do {
            let token = try jwt.sign(using: jwtSigner)
            print(jwt)

            UserDefaults.standard.setValue(token, forKey: "JWT")
        } catch {
            print(error.localizedDescription)
        }
    }
}

struct JWTClaims: Claims {
    let iss: String
    let iat: Date?
    let exp: Date?
    let scope: String
    //let aud: URL
    let aud: String
}

If I po to the debugger try jwt.sign(using: jwtSigner) it gives me the error "The provided key did not have the expected PEM headers/footers".

What am I missing here? I have checked my header and payload seem to be in the correct format.

[dhavalnenaagile]

I too have the same problem. Can you share your findings if you were able to find the solution? Thanks!

[dhavalnenaagile]

Make sure you are using proper JWTSigner type while signing the JWT in the final step. I was using wrong JWTSigner and that caused the problem. Thanks.

[alfitriv]

Hello yes, I ended up using a different JWT signer. Glad this helps for you as well. Thank you, Vania

…

On Tue, 19 Sep 2023 at 15.15 Dhaval Nena ***@***.***> wrote: Make sure you are using proper JWTSigner type while signing the JWT in the final step. I was using wrong JWTSigner and that caused the problem. Thanks. — Reply to this email directly, view it on GitHub <#114 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AEHAXXVTTG4YWJMVJZWUE6TX3FA73ANCNFSM6AAAAAAYVW3VLE> . You are receiving this because you authored the thread.Message ID: ***@***.***>