The plan is to create a pair of executables (ngrok and ngrokd) that are connected with a self-signed SSL cert. Since the client and server executables are paired, you won't be able to use any other ngrok to connect to this ngrokd, and vice versa.
Add two DNS records: one for the base domain and one for the wildcard domain. For example, if your base domain is domain.com, you'll need a record for that and for *.domain.com.
If the OS on which you'll be compiling ngrok (that's the server section below) is different than the OS on which you'll be running the client, then you will need to set the GOOS and GOARCH env variables. I run Linux everywhere, so I don't know how to do that. Please Google it or see the discussion here. If you know how to do this and want to add GOOS/GOARCH instructions here, please let me know.
MAKE SURE YOU SET NGROK_DOMAIN BELOW. Set it to the base domain, not the wildcard domain.
NGROK_DOMAIN="my.domain.com"
git clone https://github.com/inconshreveable/ngrok.git
cd ngrok
openssl genrsa -out rootCA.key 2048
openssl req -x509 -new -nodes -key rootCA.key -subj "/CN=$NGROK_DOMAIN" -days 5000 -out rootCA.pem
openssl genrsa -out device.key 2048
openssl req -new -key device.key -subj "/CN=$NGROK_DOMAIN" -out device.csr
openssl x509 -req -in device.csr -CA rootCA.pem -CAkey rootCA.key -CAcreateserial -out device.crt -days 5000
cp rootCA.pem assets/client/tls/ngrokroot.crt
# make clean
make release-server release-client
Copy bin/ngrok to whatever computer you want to connect from. Then start the server:
bin/ngrokd -tlsKey=device.key -tlsCrt=device.crt -domain="$NGROK_DOMAIN" -httpAddr=":8000" -httpsAddr=":8001"
MAKE SURE YOU SET NGROK_DOMAIN BELOW. Set it to the base domain, not the wildcard domain.
NGROK_DOMAIN="my.domain.com"
echo -e "server_addr: $NGROK_DOMAIN:4443\ntrust_host_root_certs: false" > ngrok-config
./ngrok -config=ngrok-config 80
Or for SSH forwarding: ./ngrok -config=ngrok-config --proto=tcp 22