From 82fa85594c87dc804b14fae263fbf725c4937393 Mon Sep 17 00:00:00 2001
From: Bohan Yang <youthdna@live.com>
Date: Fri, 26 Nov 2021 21:41:18 +0800
Subject: [PATCH] Add --interface, --ssh-port; Always allow low-mem

---
 README.md |  6 ++++--
 debi.sh   | 20 +++++++++++++++-----
 2 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/README.md b/README.md
index 9b26372..f48d82c 100644
--- a/README.md
+++ b/README.md
@@ -98,6 +98,8 @@ Otherwise, you can run this command to revert all changes made by the script:
 
 ## Available Options
 
+ * `--interface <string>` Manually select a network interface, e.g. eth1
+ * `--ethx` Disable *Consistent Network Device Naming* to get interface names like *ethX* back
  * `--ip <string>` Disable the auto network config (DHCP) and configure a static IP address, e.g. `10.0.0.2`, `1.2.3.4/24`, `2001:2345:6789:abcd::ef/48`
  * `--netmask <string>` e.g. `255.255.255.0`, `ffff:ffff:ffff:ffff::`
  * `--gateway <string>` e.g. `10.0.0.1`, `none` if no gateway
@@ -135,9 +137,9 @@ Otherwise, you can run this command to revert all changes made by the script:
  * `--install 'ca-certificates libpam-systemd'` Install additional APT packages. Space-separated and quoted.
  * `--safe-upgrade` **(Default)** `apt upgrade --with-new-pkgs`. [See](https://salsa.debian.org/installer-team/pkgsel/-/blob/master/debian/postinst)
  * `--full-upgrade` `apt dist-upgrade`
- * `--no-upgrade` 
- * `--ethx` Disable *Consistent Network Device Naming* to get interface names like *ethX* back
+ * `--no-upgrade`
  * `--bbr` Enable TCP BBR congestion control
+ * `--ssh-port <integer>` SSH port
  * `--hold` Don't reboot or power off after installation
  * `--power-off` Power off after installation rather than reboot
  * `--architecture <string>` e.g. `amd64`, `i386`, `arm64`, `armhf`, etc.
diff --git a/debi.sh b/debi.sh
index 14becc2..6a0ea93 100755
--- a/debi.sh
+++ b/debi.sh
@@ -195,6 +195,7 @@ has_backports() {
     return 1
 }
 
+interface=auto
 ip=
 netmask=
 gateway=
@@ -227,6 +228,7 @@ install='ca-certificates libpam-systemd'
 upgrade=
 kernel_params=
 bbr=false
+ssh_port=
 hold=false
 power_off=false
 architecture=
@@ -250,6 +252,10 @@ while [ $# -gt 0 ]; do
             ntp=ntp.aliyun.com
             security_repository=mirror
             ;;
+        --interface)
+            interface=$2
+            shift
+            ;;
         --ip)
             ip=$2
             shift
@@ -391,6 +397,10 @@ while [ $# -gt 0 ]; do
         --bbr)
             bbr=true
             ;;
+        --ssh-port)
+            ssh_port=$2
+            shift
+            ;;
         --hold)
             hold=true
             ;;
@@ -470,7 +480,7 @@ elif [ "$network_console" = true ] && [ -z "$authorized_keys_url" ]; then
     prompt_password "Choose a password for the installer user of the SSH network console: "
 fi
 
-$save_preseed << 'EOF'
+$save_preseed << EOF
 # Localization
 
 d-i debian-installer/language string en
@@ -480,7 +490,7 @@ d-i keyboard-configuration/xkb-keymap select us
 
 # Network configuration
 
-d-i netcfg/choose_interface select auto
+d-i netcfg/choose_interface select $interface
 EOF
 
 [ -n "$ip" ] && {
@@ -609,6 +619,8 @@ EOF
     fi
 }
 
+[ -n "$ssh_port" ] && configure_sshd Port "$ssh_port"
+
 $save_preseed << EOF
 
 # Clock and time zone setup
@@ -804,9 +816,7 @@ EOF
 
 installer_directory="$boot_directory$installer"
 
-# shellcheck disable=SC2034
-mem=$(grep ^MemTotal: /proc/meminfo | { read -r x y z; echo "$y"; })
-[ $((mem / 1024)) -le 512 ] && kernel_params="$kernel_params lowmem/low=1"
+kernel_params="$kernel_params lowmem/low=1"
 
 initrd="$installer_directory/initrd.gz"
 [ "$firmware" = true ] && initrd="$initrd $installer_directory/firmware.cpio.gz"