defmodule Pleroma.Web.Salmon do
+ @httpoison Application.get_env(:pleroma, :httpoison)
+
use Bitwise
+ alias Pleroma.Web.XML
+ alias Pleroma.Web.OStatus.ActivityRepresenter
+ alias Pleroma.User
+ require Logger
- def decode_and_validate(magickey, salmon) do
- {doc, _rest} = :xmerl_scan.string(to_charlist(salmon))
+ def decode(salmon) do
+ doc = XML.parse_document(salmon)
{:xmlObj, :string, data} = :xmerl_xpath.string('string(//me:data[1])', doc)
{:xmlObj, :string, sig} = :xmerl_xpath.string('string(//me:sig[1])', doc)
{:xmlObj, :string, encoding} = :xmerl_xpath.string('string(//me:encoding[1])', doc)
{:xmlObj, :string, type} = :xmerl_xpath.string('string(//me:data[1]/@type)', doc)
-
{:ok, data} = Base.url_decode64(to_string(data), ignore: :whitespace)
{:ok, sig} = Base.url_decode64(to_string(sig), ignore: :whitespace)
alg = to_string(alg)
encoding = to_string(encoding)
type = to_string(type)
- signed_text = [data, type, encoding, alg]
- |> Enum.map(&Base.url_encode64/1)
- |> Enum.join(".")
+ [data, type, encoding, alg, sig]
+ end
+
+ def fetch_magic_key(salmon) do
+ with [data, _, _, _, _] <- decode(salmon),
+ doc <- XML.parse_document(data),
+ uri when not is_nil(uri) <- XML.string_from_xpath("/entry/author[1]/uri", doc),
+ {:ok, public_key} <- User.get_public_key_for_ap_id(uri),
+ magic_key <- encode_key(public_key) do
+ {:ok, magic_key}
+ end
+ end
+
+ def decode_and_validate(magickey, salmon) do
+ [data, type, encoding, alg, sig] = decode(salmon)
+
+ signed_text =
+ [data, type, encoding, alg]
+ |> Enum.map(&Base.url_encode64/1)
+ |> Enum.join(".")
key = decode_key(magickey)
end
end
- defp decode_key("RSA." <> magickey) do
- make_integer = fn(bin) ->
+ def decode_key("RSA." <> magickey) do
+ make_integer = fn bin ->
list = :erlang.binary_to_list(bin)
- Enum.reduce(list, 0, fn (el, acc) -> (acc <<< 8) ||| el end)
+ Enum.reduce(list, 0, fn el, acc -> acc <<< 8 ||| el end)
end
- [modulus, exponent] = magickey
- |> String.split(".")
- |> Enum.map(&Base.url_decode64!/1)
- |> Enum.map(make_integer)
+ [modulus, exponent] =
+ magickey
+ |> String.split(".")
+ |> Enum.map(fn n -> Base.url_decode64!(n, padding: false) end)
+ |> Enum.map(make_integer)
{:RSAPublicKey, modulus, exponent}
end
+
+ def encode_key({:RSAPublicKey, modulus, exponent}) do
+ modulus_enc = :binary.encode_unsigned(modulus) |> Base.url_encode64()
+ exponent_enc = :binary.encode_unsigned(exponent) |> Base.url_encode64()
+
+ "RSA.#{modulus_enc}.#{exponent_enc}"
+ end
+
+ # Native generation of RSA keys is only available since OTP 20+ and in default build conditions
+ # We try at compile time to generate natively an RSA key otherwise we fallback on the old way.
+ try do
+ _ = :public_key.generate_key({:rsa, 2048, 65537})
+
+ def generate_rsa_pem do
+ key = :public_key.generate_key({:rsa, 2048, 65537})
+ entry = :public_key.pem_entry_encode(:RSAPrivateKey, key)
+ pem = :public_key.pem_encode([entry]) |> String.trim_trailing()
+ {:ok, pem}
+ end
+ rescue
+ _ ->
+ def generate_rsa_pem do
+ port = Port.open({:spawn, "openssl genrsa"}, [:binary])
+
+ {:ok, pem} =
+ receive do
+ {^port, {:data, pem}} -> {:ok, pem}
+ end
+
+ Port.close(port)
+
+ if Regex.match?(~r/RSA PRIVATE KEY/, pem) do
+ {:ok, pem}
+ else
+ :error
+ end
+ end
+ end
+
+ def keys_from_pem(pem) do
+ [private_key_code] = :public_key.pem_decode(pem)
+ private_key = :public_key.pem_entry_decode(private_key_code)
+ {:RSAPrivateKey, _, modulus, exponent, _, _, _, _, _, _, _} = private_key
+ public_key = {:RSAPublicKey, modulus, exponent}
+ {:ok, private_key, public_key}
+ end
+
+ def encode(private_key, doc) do
+ type = "application/atom+xml"
+ encoding = "base64url"
+ alg = "RSA-SHA256"
+
+ signed_text =
+ [doc, type, encoding, alg]
+ |> Enum.map(&Base.url_encode64/1)
+ |> Enum.join(".")
+
+ signature =
+ signed_text
+ |> :public_key.sign(:sha256, private_key)
+ |> to_string
+ |> Base.url_encode64()
+
+ doc_base64 =
+ doc
+ |> Base.url_encode64()
+
+ # Don't need proper xml building, these strings are safe to leave unescaped
+ salmon = """
+ <?xml version="1.0" encoding="UTF-8"?>
+ <me:env xmlns:me="http://salmon-protocol.org/ns/magic-env">
+ <me:data type="application/atom+xml">#{doc_base64}</me:data>
+ <me:encoding>#{encoding}</me:encoding>
+ <me:alg>#{alg}</me:alg>
+ <me:sig>#{signature}</me:sig>
+ </me:env>
+ """
+
+ {:ok, salmon}
+ end
+
+ def remote_users(%{data: %{"to" => to} = data}) do
+ to = to ++ (data["cc"] || [])
+
+ to
+ |> Enum.map(fn id -> User.get_cached_by_ap_id(id) end)
+ |> Enum.filter(fn user -> user && !user.local end)
+ end
+
+ defp send_to_user(%{info: %{"salmon" => salmon}}, feed, poster) do
+ with {:ok, %{status_code: code}} <-
+ poster.(
+ salmon,
+ feed,
+ [{"Content-Type", "application/magic-envelope+xml"}],
+ timeout: 10000,
+ recv_timeout: 20000,
+ hackney: [pool: :default]
+ ) do
+ Logger.debug(fn -> "Pushed to #{salmon}, code #{code}" end)
+ else
+ e -> Logger.debug(fn -> "Pushing Salmon to #{salmon} failed, #{inspect(e)}" end)
+ end
+ end
+
+ defp send_to_user(_, _, _), do: nil
+
+ @supported_activities [
+ "Create",
+ "Follow",
+ "Like",
+ "Announce",
+ "Undo",
+ "Delete"
+ ]
+ def publish(user, activity, poster \\ &@httpoison.post/4)
+
+ def publish(%{info: %{"keys" => keys}} = user, %{data: %{"type" => type}} = activity, poster)
+ when type in @supported_activities do
+ feed = ActivityRepresenter.to_simple_form(activity, user, true)
+
+ if feed do
+ feed =
+ ActivityRepresenter.wrap_with_entry(feed)
+ |> :xmerl.export_simple(:xmerl_xml)
+ |> to_string
+
+ {:ok, private, _} = keys_from_pem(keys)
+ {:ok, feed} = encode(private, feed)
+
+ remote_users(activity)
+ |> Enum.each(fn remote_user ->
+ Task.start(fn ->
+ Logger.debug(fn -> "Sending Salmon to #{remote_user.ap_id}" end)
+ send_to_user(remote_user, feed, poster)
+ end)
+ end)
+ end
+ end
+
+ def publish(%{id: id}, _, _), do: Logger.debug(fn -> "Keys missing for user #{id}" end)
end