iankelling.org Git - distro-setup/blob - filesystem/usr/local/bin/ethusb-static

   1 #!/bin/bash
   2 # I, Ian Kelling, follow the GNU license recommendations at
   3 # https://www.gnu.org/licenses/license-recommendations.en.html. They
   4 # recommend that small programs, < 300 lines, be licensed under the
   5 # Apache License 2.0. This file contains or is part of one or more small
   6 # programs. If a small program grows beyond 300 lines, I plan to switch
   7 # its license to GPL.
   8
   9 # Copyright 2024 Ian Kelling
  10
  11 # Licensed under the Apache License, Version 2.0 (the "License");
  12 # you may not use this file except in compliance with the License.
  13 # You may obtain a copy of the License at
  14
  15 #     http://www.apache.org/licenses/LICENSE-2.0
  16
  17 # Unless required by applicable law or agreed to in writing, software
  18 # distributed under the License is distributed on an "AS IS" BASIS,
  19 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  20 # See the License for the specific language governing permissions and
  21 # limitations under the License.
  22
  23 if ! test "$BASH_VERSION"; then echo "error: shell is not bash" >&2; exit 1; fi
  24 shopt -s inherit_errexit 2>/dev/null ||: # ignore fail in bash < 4.4
  25 set -eE -o pipefail
  26 trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR
  27
  28 [[ $EUID == 0 ]] || exec sudo -E "${BASH_SOURCE[0]}" "$@"
  29
  30
  31 shopt -s nullglob
  32
  33 # we already configured the interface once, afterwards, comment and
  34 # uncomment to enable/disable. This makes it so we don't depend on /p
  35 # being mounted.
  36
  37 if [[ -s /etc/network/interfaces.d/ethusb ]]; then
  38   sed -i --follow-symlinks 's/^#//' /etc/network/interfaces.d/ethusb
  39   exit 0
  40 fi
  41
  42
  43 while read -r ip host mac; do
  44   if [[ $mac != usb ]]; then
  45     continue
  46   fi
  47   if [[ $host = ${HOSTNAME}c ]]; then
  48     usbip=$ip
  49     break
  50   fi
  51 done </p/c/host-info
  52
  53 if [[ ! $usbip ]]; then
  54   exit 0
  55 fi
  56
  57 ethx=0
  58
  59 # device that has an eth0, but we aren't using it because it is
  60 # broken. We could just hardcode a mac comparison with `cat
  61 # /sys/class/net/eth0/address` but this is cooler.
  62 if [[ -e  /sys/class/net/eth0 ]]; then
  63   bus_info=$(ethtool -i eth0 | awk '$1 == "bus-info:" { print $2 }')
  64   if [[ $bus_info != usb* ]]; then
  65     ethx=1
  66   fi
  67 fi
  68
  69 cat >/etc/network/interfaces.d/ethusb <<EOF
  70 auto eth$ethx
  71 iface eth$ethx inet static
  72   address 10.2.0.$ip/16
  73   gateway 10.2.0.1
  74 EOF