Merge branch 'readme' into 'main'

readme: unifiedpush gateway

See merge request famedly/fluffychat!418

README.md

@@ -132,22 +132,25 @@ Next, you add the `repo.unifiedpush.org` repository to fdroid and install the go
 ## Matrix-specific re-write proxy
 Until [MSC2970](https://github.com/matrix-org/matrix-doc/pull/2970) is figured out we unfortunately
 need another simple re-write proxy. By default the one at https://matrix.gateway.unifiedpush.org
-is used, however you can easily self-host it. For that, add to your nginx config on the same domain you serve gotify the following:
+is used, however you can easily self-host it. For that, add to your nginx config on the same domain you serve gotify the following (change *relay.example.tld*):
 ```
-resolver 8.8.8.8;
+resolver 9.9.9.9;
 
 location /_matrix/push/v1/notify {
     set $target '';
     if ($request_method = GET ) {
-        return 200 '{"gateway":"matrix"}';
+        return 200 '{"gateway":"matrix","unifiedpush":{"gateway":"matrix"}}';
     }
     access_by_lua_block {
         local cjson = require("cjson")
         ngx.req.read_body()
         local body = ngx.req.get_body_data()
         local parsedBody = cjson.decode(body)
+        local accepted = "https://relay.example.tld/"
         ngx.var.target = parsedBody["notification"]["devices"][1]["pushkey"]
         ngx.req.set_body_data(body)
+        if(string.sub(ngx.var.target,1,string.len(accepted))~=accepted) then ngx.var.target="http://0.0.0.0/"
+        end
     }
     proxy_set_header Content-Type application/json;
     proxy_set_header Host $host;