Crypto Exception in Elixir - cryptography

Question

I have configured an elixir app and defined admin routes. But, I am getting the following error while trying to access any routes.
(exit) an exception was raised:
** (ArgumentError) argument error
(crypto) :crypto.hmac_nif(:sha256, {:system, "Zpumk6KLEY8Qx826qspHhYrpTpDswFzHL/64aJWqhPyYZQWbV3hWq+nUIPQRMwLn"},
<<48, 70, 98, 86, 85, 68, 57, 56, 0, 0, 0, 1>>)
(crypto) crypto.erl:925: :crypto.hmac/6
(plug) lib/plug/crypto/key_generator.ex:64: Plug.Crypto.KeyGenerator.generate/7
(plug) lib/plug/crypto/key_generator.ex:50: Plug.Crypto.KeyGenerator.with_cache/3
(plug) lib/plug/session/cookie.ex:88: Plug.Session.COOKIE.get/3
(plug) lib/plug/session.ex:75: anonymous fn/5 in Plug.Session.fetch_session/1
(plug) lib/plug/debugger.ex:195: Plug.Debugger.maybe_fetch_session/1
(plug) lib/plug/debugger.ex:150: Plug.Debugger.render/6
(plug) lib/plug/debugger.ex:129: Plug.Debugger.catch/5
(my_app) lib/my_app_web/endpoint.ex:1: MyAppWeb.Endpoint.call/2
(plug) lib/plug/adapters/cowboy/handler.ex:15: Plug.Adapters.Cowboy.Handler.upgrade/4
Here is the content of lib/my_app_web/endpoint.ex.
defmodule MyAppWeb.Endpoint do
use Phoenix.Endpoint, otp_app: :my_app
socket "/socket", MyAppWeb.UserSocket
# Serve at "/" the static files from "priv/static" directory.
#
# You should set gzip to true if you are running phoenix.digest
# when deploying your static files in production.
plug Plug.Static,
at: "/", from: :my_app, gzip: false,
only: ~w(css fonts images js favicon.ico robots.txt)
# Code reloading can be explicitly enabled under the
# :code_reloader configuration of your endpoint.
if code_reloading? do
socket "/phoenix/live_reload/socket", Phoenix.LiveReloader.Socket
plug Phoenix.LiveReloader
plug Phoenix.CodeReloader
end
plug Plug.RequestId
plug Plug.Logger
plug Plug.Parsers,
parsers: [:urlencoded, :multipart, :json, Absinthe.Plug.Parser],
pass: ["*/*"],
json_decoder: Poison
plug Plug.MethodOverride
plug Plug.Head
# The session will be stored in the cookie and signed,
# this means its contents can be read but not tampered with.
# Set :encryption_salt if you would also like to encrypt it.
plug Plug.Session,
store: :cookie,
key: "_my_app_key",
signing_salt: "0FbVUD98"
plug MyAppWeb.Router
#doc """
Callback invoked for dynamically configuring the endpoint.
It receives the endpoint configuration and checks if
configuration should be loaded from the system environment.
"""
def init(_key, config) do
if config[:load_from_system_env] do
port = System.get_env("PORT") || raise "expected the PORT environment variable to be set"
{:ok, Keyword.put(config, :http, [:inet6, port: port])}
else
{:ok, config}
end
end
end
Anyone, please help?

Answer 1

(exit) an exception was raised:
** (ArgumentError) argument error (crypto) :crypto.hmac_nif(:sha256, {:system, "Zpumk6KLEY8Qx826qspHhYrpTpDswFzHL/64aJWqhPyYZQWbV3hWq+nUIPQRMwLn"}, <<48, 70, 98, 86, 85, 68, 57, 56, 0, 0, 0, 1>>)
(crypto) crypto.erl:925: :crypto.hmac/6
(plug) lib/plug/crypto/key_generator.ex:64: Plug.Crypto.KeyGenerator.generate/7
(plug) lib/plug/crypto/key_generator.ex:50: Plug.Crypto.KeyGenerator.with_cache/3
(plug) lib/plug/session/cookie.ex:88: Plug.Session.COOKIE.get/3
lib/plug/adapters/cowboy/handler.ex:15: Plug.Adapters.Cowboy.Handler.upgrade/4
Your error log is related to Plug.Session.COOKIE.
As the doc said,
Since this store uses crypto features, it requires you to set the :secret_key_base field in your connection. This can be easily achieved with a plug:
It seems that you didn't do this part in your code.