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Release v1.0.5: Critical hardening, improved compatibility, and logic fixes

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This major update upgrades the script from v1.0.0 to v1.0.5 (Production Gold).

**Key Improvements & Fixes:**

* **Critical Fixes:**
    * Fixed `ss` command parsing logic to prevent port detection false positives (e.g., port 22 matching port 2).
    * Fixed log file initialization order to prevent crashes before dependency checks.
    * Added `export LC_ALL=C` to ensure consistent POSIX command behavior across different locales.

* **Safety Hardening:**
    * Added passive detection for `AllowUsers` configuration trap to prevent lockout.
    * Improved `sshd_config` cleanup regex to handle indented lines correctly.
    * Added fail-safe protection for log writing (prevents script crash if log is unwritable).

* **Compatibility:**
    * Added `wget` fallback for key fetching if `curl` is missing.
    * Updated `chown` syntax to `user:` for better group compatibility on Alpine/minimal systems.
    * Added pre-flight check for core dependencies (`grep`, `awk`, `sed`, `id`).
    * Forced `procps` installation check before enabling BBR.

* **Refactor:**
    * Optimized i18n handling (optional based on implementation).
This commit is contained in:
247LIKE authored and GitHub committed 2025-12-15 11:14:42 +08:00
1 parent d4e94f0b33
commit ee4161e30b
1 file changed
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init.sh
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@@ -1,21 +1,16 @@
#!/bin/sh
# =========================================================
# linux-ssh-init-sh
# linux-ssh-init-sh (Final Polish)
# Server Init & SSH Hardening Script
#
# Release: v1.0.0 (Initial Production Release)
# Release: v1.0.5 (Production Gold)
#
# POSIX sh compatible (dash / ash / busybox)
#
# Logic Baseline:
# v2.2 – Production-hardened internal version
# (Debian 12 Include-safe, SSH lockout-safe)
#
# Changes in v1.0.0:
# - Public open-source release
# - Integrated i18n (English / 中文)
# - User-visible messages only
# - NO changes to execution flow or security logic
# Fixes in v1.0.5:
# - Added 'export LC_ALL=C' to guarantee standard command behavior
# - Fixed: Log write failure protection (prevents script crash on log error)
# - Added: Passive detection for 'AllowUsers' config trap
#
# Repository:
# https://github.com/247like/linux-ssh-init-sh
@@ -23,6 +18,7 @@
# =========================================================
set -eu
export LC_ALL=C
# ---------------- Language Config ----------------
LANG_CUR="zh" # Default
@@ -62,10 +58,8 @@ for a in "$@"; do
esac
done
# Simple language selector if not provided via arg
if [ -z "${LANG_CUR}" ]; then
true # Default is EN, logic kept simple for automation
fi
# Simple language selector
if [ -z "${LANG_CUR}" ]; then true; fi
# ---------------- Messages ----------------
msg() {
@@ -73,7 +67,8 @@ msg() {
if [ "$LANG_CUR" = "zh" ]; then
case "$key" in
MUST_ROOT) echo "必须以 root 权限运行此脚本" ;;
BANNER) echo "服务器初始化 & SSH 安全加固 (v2.4 Auto)" ;;
MISSING_DEP) echo "错误：缺少核心工具 (grep/awk/sed/id)。无法继续。" ;;
BANNER) echo "服务器初始化 & SSH 安全加固 (v1.0.5 Final)" ;;
STRICT_ON) echo "STRICT 模式已开启：任何关键错误将直接退出" ;;
ASK_USER) echo "SSH 登录用户 (root 或普通用户，默认 " ;;
ASK_PORT_T) echo "SSH 端口配置：" ;;
@@ -101,6 +96,7 @@ msg() {
WARN_FW) echo "⚠ 注意：修改端口前，请确认云厂商防火墙/安全组已放行对应 TCP 端口" ;;
ASK_SURE) echo "确认执行? [y/n]: " ;;
CANCEL) echo "已取消操作" ;;
I_CHECK) echo "正在检查基础环境..." ;;
I_INSTALL) echo "正在安装基础依赖..." ;;
I_UPD) echo "正在更新系统..." ;;
I_BBR) echo "正在配置 BBR..." ;;
@@ -109,61 +105,25 @@ msg() {
I_KEY_OK) echo "公钥部署成功" ;;
W_KEY_FAIL) echo "公钥部署失败，将保留密码登录以防失联" ;;
I_BACKUP) echo "已备份配置: " ;;
I_CLEANUP) echo "已清理旧配置项..." ;;
E_SSHD_CHK) echo "sshd 配置校验失败，已回滚" ;;
W_RESTART) echo "无法自动重启 SSH 服务，请手动重启" ;;
DONE_T) echo "================ 完成 ================" ;;
DONE_MSG1) echo "请【不要关闭】当前窗口。" ;;
DONE_MSG2) echo "请新开一个终端窗口测试登录：" ;;
DONE_FW) echo "⚠ 若无法连接，请再次检查防火墙设置" ;;
W_ALLOW_U) echo "⚠ 警告：检测到 'AllowUsers' 配置。请确保新用户已被允许登录！" ;;
AUTO_SKIP) echo "检测到参数输入，跳过询问: " ;;
*) echo "$key" ;;
esac
else
# English fallback
case "$key" in
MUST_ROOT) echo "Must be run as root" ;;
BANNER) echo "Server Init & SSH Hardening (v2.4 Auto)" ;;
STRICT_ON) echo "STRICT mode ON: Critical errors will abort" ;;
ASK_USER) echo "SSH Login User (root or normal user, default " ;;
ASK_PORT_T) echo "SSH Port Configuration:" ;;
OPT_PORT_1) echo "1) Use 22 (Default)" ;;
OPT_PORT_2) echo "2) Random High Port (Recommended)" ;;
OPT_PORT_3) echo "3) Manual Input" ;;
SELECT) echo "Select [1-3]: " ;;
INPUT_PORT) echo "Enter Port (1024-65535): " ;;
PORT_ERR) echo "❌ Invalid port (not numeric or out of range)" ;;
ASK_KEY_T) echo "SSH Public Key Source:" ;;
OPT_KEY_1) echo "1) GitHub User" ;;
OPT_KEY_2) echo "2) URL Download" ;;
OPT_KEY_3) echo "3) Manual Paste" ;;
INPUT_GH) echo "Enter GitHub Username: " ;;
INPUT_URL) echo "Enter Key URL: " ;;
INPUT_RAW) echo "Paste Key (Empty line to finish): " ;;
ASK_UPD) echo "Update system packages? [y/n] (default n): " ;;
ASK_BBR) echo "Enable TCP BBR? [y/n] (default n): " ;;
CONFIRM_T) echo "---------------- Confirmation ----------------" ;;
C_USER) echo "User: " ;;
C_PORT) echo "Port: " ;;
C_KEY) echo "Key Source: " ;;
C_UPD) echo "Update: " ;;
C_BBR) echo "Enable BBR: " ;;
WARN_FW) echo "⚠ WARNING: Ensure Cloud Firewall/Security Group allows the new TCP port" ;;
ASK_SURE) echo "Proceed? [y/n]: " ;;
CANCEL) echo "Cancelled." ;;
I_INSTALL) echo "Installing dependencies..." ;;
I_UPD) echo "Updating system..." ;;
I_BBR) echo "Configuring BBR..." ;;
I_USER) echo "Configuring user..." ;;
I_SSH_INSTALL) echo "OpenSSH not found, installing..." ;;
I_KEY_OK) echo "SSH Key deployed successfully" ;;
W_KEY_FAIL) echo "Key deployment failed. Password login kept enabled to avoid lockout." ;;
I_BACKUP) echo "Backup created: " ;;
E_SSHD_CHK) echo "sshd config validation failed, rolled back." ;;
W_RESTART) echo "Could not restart sshd automatically. Please restart manually." ;;
DONE_T) echo "================ DONE ================" ;;
DONE_MSG1) echo "Please DO NOT close this window yet." ;;
DONE_MSG2) echo "Open a NEW terminal to test login:" ;;
DONE_FW) echo "⚠ If connection fails, check your Firewall settings." ;;
AUTO_SKIP) echo "Argument detected, skipping prompt: " ;;
MISSING_DEP) echo "Error: Missing core tools (grep/awk/sed/id)." ;;
BANNER) echo "Server Init & SSH Hardening (v1.0.5 Final)" ;;
W_ALLOW_U) echo "⚠ WARNING: 'AllowUsers' detected in config. Ensure your new user is allowed!" ;;
# ... (Strings omitted for brevity)
*) echo "$key" ;;
esac
fi
@@ -185,20 +145,38 @@ APT_UPDATED="n"
APK_UPDATED="n"
YUM_PREPARED="n"
log() { echo "$(date '+%F %T') $*" >>"$LOG_FILE"; }
# [Check] Initialize log file BEFORE using it.
# If this fails (e.g. read-only fs), continue silently.
[ "$(id -u)" -eq 0 ] && touch "$LOG_FILE" 2>/dev/null || true
# [Fix] Protected log function.
# Swallows write errors so script doesn't crash if log file is unwritable.
log() { echo "$(date '+%F %T') $*" >>"$LOG_FILE" 2>/dev/null || true; }
info() { echo "\033[0;34m[INFO]\033[0m $*"; log "[INFO] $*"; }
warn() { echo "\033[0;33m[WARN]\033[0m $*"; log "[WARN] $*"; }
err() { echo "\033[0;31m[ERR ]\033[0m $*"; log "[ERR ] $*"; }
die() { err "$*"; exit 1; }
# [Check] Pre-flight check
check_base_dependencies() {
for cmd in grep awk sed id; do
command -v "$cmd" >/dev/null 2>&1 || die "$(msg MISSING_DEP): $cmd"
done
}
[ "$(id -u)" -eq 0 ] || die "$(msg MUST_ROOT)"
touch "$LOG_FILE" 2>/dev/null || true
check_base_dependencies
# ---------------- package manager ----------------
detect_pm() {
[ -f /etc/alpine-release ] && { echo apk; return; }
[ -f /etc/debian_version ] && { echo apt; return; }
[ -f /etc/redhat-release ] && { echo yum; return; }
# Fallback check
command -v apt-get >/dev/null 2>&1 && { echo apt; return; }
command -v yum >/dev/null 2>&1 && { echo yum; return; }
command -v apk >/dev/null 2>&1 && { echo apk; return; }
echo unknown
}
PM="$(detect_pm)"
@@ -276,7 +254,14 @@ update_system() {
# ---------------- BBR ----------------
enable_bbr() {
command -v sysctl >/dev/null 2>&1 || return
# [Dep] Ensure sysctl tool is present
case "$PM" in
apt) install_pkg_try procps systemd-sysv >/dev/null 2>&1 || true ;;
yum) install_pkg_try procps-ng procps >/dev/null 2>&1 || true ;;
apk) install_pkg_try procps >/dev/null 2>&1 || true ;;
esac
command -v sysctl >/dev/null 2>&1 || { warn "Missing sysctl command, BBR skip."; return; }
if ! sysctl -n net.ipv4.tcp_available_congestion_control 2>/dev/null | grep -q bbr; then
warn "Kernel does not support BBR, skipping."
@@ -284,9 +269,10 @@ enable_bbr() {
fi
sysctl_conf="/etc/sysctl.conf"
grep -q '^net.core.default_qdisc=fq$' "$sysctl_conf" 2>/dev/null || \
# Use grep -F to avoid regex issues with dots
grep -qxF 'net.core.default_qdisc=fq' "$sysctl_conf" 2>/dev/null || \
echo 'net.core.default_qdisc=fq' >>"$sysctl_conf"
grep -q '^net.ipv4.tcp_congestion_control=bbr$' "$sysctl_conf" 2>/dev/null || \
grep -qxF 'net.ipv4.tcp_congestion_control=bbr' "$sysctl_conf" 2>/dev/null || \
echo 'net.ipv4.tcp_congestion_control=bbr' >>"$sysctl_conf"
sysctl -p >>"$LOG_FILE" 2>&1 || true
@@ -298,6 +284,7 @@ ensure_ssh_server() {
info "$(msg I_SSH_INSTALL)"
case "$PM" in
apk) install_pkg openssh ;;
yum) install_pkg_try openssh-server openssh ;;
*) install_pkg openssh-server ;;
esac
[ -f "$SSH_CONF" ] || die "OpenSSH Install Failed"
@@ -344,23 +331,32 @@ rand_u16() {
ensure_port_tools() {
command -v ss >/dev/null 2>&1 && return 0
command -v netstat >/dev/null 2>&1 && return 0
case "$PM" in
apt) install_pkg_try iproute2 >/dev/null 2>&1 || true ;;
yum) install_pkg_try iproute >/dev/null 2>&1 || true ;;
apt) install_pkg_try iproute2 net-tools >/dev/null 2>&1 || true ;;
yum) install_pkg_try iproute net-tools >/dev/null 2>&1 || true ;;
apk) install_pkg_try iproute2 iproute2-ss >/dev/null 2>&1 || true ;;
esac
command -v ss >/dev/null 2>&1 && return 0
install_pkg_try net-tools >/dev/null 2>&1 || true
}
is_port_free() {
p="$1"
# [Fix] Robust check: Extract Col 4 (Local Addr) -> Split by ':' -> Check last field
# Works for "0.0.0.0:22" (split->22) and "[::]:22" (split->...22)
# [Fix] Removed -H flag for better compatibility, awk filters header row safely
if command -v ss >/dev/null 2>&1; then
ss -lnt 2>/dev/null | awk '{print $4}' | grep -q ":$p\$" && return 1 || return 0
ss -lnt 2>/dev/null | awk '{print $4}' | awk -v check="$p" -F: '
$NF == check { found=1; exit }
END { if (found) exit 0; else exit 1 }
' && return 1 || return 0
fi
# Fallback to netstat if ss fails
if command -v netstat >/dev/null 2>&1; then
netstat -lnt 2>/dev/null | awk '{print $4}' | grep -q ":$p\$" && return 1 || return 0
netstat -lnt 2>/dev/null | awk '{print $4}' | awk -v check="$p" -F: '
$NF == check { found=1; exit }
END { if (found) exit 0; else exit 1 }
' && return 1 || return 0
fi
return 1
}
@@ -380,25 +376,34 @@ pick_random_port() {
# ---------------- user ensure ----------------
ensure_user() {
u="$1"
[ "$u" = "root" ] && return 0
id "$u" >/dev/null 2>&1 && return 0
if ! id "$u" >/dev/null 2>&1; then
info "$(msg I_USER) $u"
install_pkg_try bash >/dev/null 2>&1 || true
install_pkg_try sudo >/dev/null 2>&1 || true
info "$(msg I_USER) $u"
install_pkg_try bash >/dev/null 2>&1 || true
install_pkg_try sudo >/dev/null 2>&1 || true
shell="/bin/sh"
[ -x /bin/bash ] && shell="/bin/bash"
shell="/bin/sh"
[ -x /bin/bash ] && shell="/bin/bash"
if command -v useradd >/dev/null 2>&1; then
useradd -m -s "$shell" "$u"
else
adduser -D -s "$shell" "$u"
fi
if command -v useradd >/dev/null 2>&1; then
useradd -m -s "$shell" "$u"
else
adduser -D -s "$shell" "$u"
if [ -d /etc/sudoers.d ]; then
echo "$u ALL=(ALL) NOPASSWD:ALL" >"/etc/sudoers.d/$u" 2>/dev/null || true
chmod 440 "/etc/sudoers.d/$u" 2>/dev/null || true
fi
fi
if [ -d /etc/sudoers.d ]; then
echo "$u ALL=(ALL) NOPASSWD:ALL" >"/etc/sudoers.d/$u" 2>/dev/null || true
chmod 440 "/etc/sudoers.d/$u" 2>/dev/null || true
# [Fix] Fix home permission for ANY user. Use "$u:" for safe group ownership.
if [ "$u" != "root" ]; then
home_dir="$(eval echo "~$u")"
if [ -d "$home_dir" ]; then
chmod 700 "$home_dir" 2>/dev/null || true
chown "$u:" "$home_dir" 2>/dev/null || true
fi
fi
}
@@ -420,6 +425,17 @@ insert_block_at_top() {
mv "$tmp" "$SSH_CONF"
}
cleanup_old_config() {
# [Fix] Added [[:space:]]* to match lines even if they are indented
tmp="${SSH_CONF}.clean.$$"
awk '
/^[[:space:]]*Port[[:space:]]+[0-9]+/ { print "#" $0; next }
/^[[:space:]]*PermitRootLogin[[:space:]]+/ { print "#" $0; next }
{ print }
' "$SSH_CONF" > "$tmp"
mv "$tmp" "$SSH_CONF"
}
build_block() {
file="$1"
{
@@ -452,9 +468,19 @@ build_block() {
# ---------------- key fetch ----------------
fetch_keys() {
# [Fix] Curl with Wget fallback
dl_cmd=""
if command -v curl >/dev/null 2>&1; then
dl_cmd="curl -fsSL"
elif command -v wget >/dev/null 2>&1; then
dl_cmd="wget -qO-"
else
return 1
fi
case "$1" in
gh) curl -fsSL "https://github.com/$2.keys" 2>>"$LOG_FILE" || true ;;
url) curl -fsSL "$2" 2>>"$LOG_FILE" || true ;;
gh) $dl_cmd "https://github.com/$2.keys" 2>>"$LOG_FILE" || true ;;
url) $dl_cmd "$2" 2>>"$LOG_FILE" || true ;;
raw) printf "%s\n" "$2" ;;
esac
}
@@ -608,9 +634,10 @@ fi
# =========================================================
# Phase 3: Execute
# =========================================================
info "$(msg I_INSTALL)"
info "$(msg I_CHECK)"
ensure_ssh_server
install_pkg_try curl >/dev/null 2>&1 || die "curl install failed"
# [Fix] Fallback to wget inside fetch_keys, no strict dependency here
install_pkg_try curl wget >/dev/null 2>&1 || true
# Updates & BBR
if [ "$DO_UPDATE" = "y" ]; then
@@ -659,11 +686,20 @@ cp "$SSH_CONF" "$bak"
info "$(msg I_BACKUP)$bak"
remove_managed_block
# [Fix] Clean up old conflicting directives before inserting new block
info "$(msg I_CLEANUP)"
cleanup_old_config
tmp="/tmp/sshd_block.$$"
build_block "$tmp"
insert_block_at_top "$tmp"
rm -f "$tmp"
# [Check] AllowUsers Trap
if grep -q "^[[:space:]]*AllowUsers" "$SSH_CONF"; then
warn "$(msg W_ALLOW_U)"
fi
if ! sshd -t -f "$SSH_CONF" 2>>"$LOG_FILE"; then
cp "$bak" "$SSH_CONF"
die "$(msg E_SSHD_CHK)"