Use an LTE modem to send/receive SMS over email.
I needed a self-hosted solution to receiving SMS (specifically verification codes) while traveling internationally or otherwise without home carrier connectivity. I did not want to buy a whole smartphone and deal with the issues of having an android OS running 24/7/365.
This is the result of an evening of tinkering with AT commands. It may not be perfect and there is some potential code cleanup that could be done.
The specific parts that I used were for a Raspberry Pi, but this program should be usable with any serial modem that supports the necessary AT commands
- Raspberry Pi
- Waveshare HAT SIM7600G-H (or compatible)
- Cheapo SIM card
Setup the modem so that there is an accessible serial port to send AT commands to it.
You can test that the serial port is working by connecting using a serial console like cu,
and sending AT. You should get a response of OK.
Copy the appsettings.example.json to appsettings.json and fill in the <placeholders>.
Build it using dotnet build.
P.S. There is an included sample systemd service that can be used to set this up.