Include known SSH hostkeys for providers

#3

Makefile

@@ -7,6 +7,7 @@ install:
 	cp sshtunnel.service ${DESTDIR}/usr/lib/systemd/system/
 	mkdir -p ${DESTDIR}/root/.ssh/
 	cp sshtunnel.config.sh ${DESTDIR}/root/.ssh/
+	cp providers_known_hosts ${DESTDIR}/root/.ssh/
 
 install_all: install reload_service
 

providers_known_hosts

@@ -0,0 +1,8 @@
+a.pinggy.io ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIBPtPwrVBlNxxpb9G1ghX2Yj4AsSxeBsPUTIlBXeMMGX
+burrow.io ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBE0At82khKosr82MRSAbLrOfyaJyWFqo02++FeQnUO4iot7GC5dO94QzVFnQk5Lf4VBIzbc6EKmWSqk982Mj30w=
+localhost.run ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC3lJnhW1oCXuAYV9IBdcJA+Vx7AHL5S/ZQvV2fhceOAPgO2kNQZla6xvUwoE4iw8lYu3zoE1KtieCU9yInWOVI6W/wFaT/ETH1tn55T2FVsK/zaxPiHZVJGLPPdEEid0vS2p1JDfc9onZ0pNSHLl1QusIOeMUyZ2bUMMLLgw46KOT9S3s/LmxgoJ3PocVUn5rVXz/Dng7Y8jYNe4IFrZOAUsi7hNBa+OYja6ceefpDvNDEJ1BdhbYfGolBdNA7f+FNl0kfaWru4Cblr843wBe2ckO/sNqgeAMXO/qH+SSgQxUXF2AgAw+TGp3yCIyYoOPvOgvcPsQziJLmDbUuQpnH
+remote.moe ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIN9FdPGvDymYCFJ4oBqECb8yr04LpA4bStYZbgrGzEGm
+serveo.net ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDxYGqSKVwJpQD1F0YIhz+bd5lpl7YesKjtrn1QD1RjQcSj724lJdCwlv4J8PcLuFFtlAA8AbGQju7qWdMN9ihdHvRcWf0tSjZ+bzwYkxaCydq4JnCrbvLJPwLFaqV1NdcOzY2NVLuX5CfY8VTHrps49LnO0QpGaavqrbk+wTWDD9MHklNfJ1zSFpQAkSQnSNSYi/M2J3hX7P0G2R7dsUvNov+UgNKpc4n9+Lq5Vmcqjqo2KhFyHP0NseDLpgjaqGJq2Kvit3QowhqZkK4K77AA65CxZjdDfpjwZSuX075F9vNi0IFpFkGJW9KlrXzI4lIzSAjPZBURhUb8nZSiPuzj
+srv.us ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIIpS9PVjoJ6ZkrOkE7+kwipzwk658AP53s2u2LyZGniR
+ssh-j.com ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIIiyFQuTwegicQ+8w7dLA7A+4JMZkCk8TLWrKPklWcRt
+jkl.mn ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIBeX5GOXbddC7u8uo5pc1TPZQxQPn05M0VFfzAfA/d1S

sshtunnel.sh

@@ -129,7 +129,7 @@ _ssh_connect() {
     # shellcheck disable=SC2155
     local t0=$(date +%s)
     # shellcheck disable=SC2086
-    ssh $ssh_cmd_args -N -o ExitOnForwardFailure=yes -o BatchMode=yes
+    ssh $ssh_cmd_args -N -o ExitOnForwardFailure=yes -o BatchMode=yes -o GlobalKnownHostsFile=/root/.ssh/providers_known_hosts
     local exit_code="$?"
     # Reconnect immediately when the connection was lost, but wait for a minute if ssh was terminating just recently
     # shellcheck disable=SC2155