laily/.dotfile
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

feat: add ssh-harden

Browse Source
This commit is contained in:
laily
2026-07-25 21:49:20 +08:00
parent 5598ad5b3f
commit c974d858be
1 changed files with 74 additions and 32 deletions
Download Patch File Download Diff File Expand all files Collapse all files
script/ssh-harden.sh
+74 -32
View File
@@ -13,11 +13,10 @@ usage() {
cat <<'EOF'
用法: sudo ssh-harden [--user <用户名>] [--skip-key-check] [--yes]
默认在确认目标用户已有 SSH 公钥后，写入 /etc/ssh/sshd_config.d/99-dotfile-key-only.conf：
默认在确认目标用户已有 SSH 公钥后，直接更新 /etc/ssh/sshd_config 的全局配置：
PubkeyAuthentication yes
PasswordAuthentication no
KbdInteractiveAuthentication no
ChallengeResponseAuthentication no
PermitRootLogin no
Port 55522
@@ -37,7 +36,7 @@ usage() {
- 脚本不会创建 SSH 密钥；目标用户的 ~/.ssh/authorized_keys 中必须已有有效公钥。
- 使用 -k/--skip-key-check 时，必须已有其他已验证的登录方式（例如 Tailscale SSH
或云控制台）；该选项仅跳过本地 authorized_keys 检查。
- 写入前会校验 sshd 配置，且重载后会再次核对生效设置；失败会恢复原文件。
- 写入前会备份并校验 sshd_config，且重载后会再次核对生效设置；失败会恢复原文件。
- 若 UFW 已启用，脚本会自动放行 TCP 55522；云安全组和其他防火墙仍需自行放行。
- 请保持当前 SSH 会话不要退出，另开一个终端验证密钥登录成功后再关闭。
EOF
@@ -190,6 +189,55 @@ reload_sshd() {
return 1
}
write_hardened_config() {
awk -v port="$SSH_PORT" '
function emit_missing() {
if (!seen["pubkeyauthentication"]) print "PubkeyAuthentication yes"
if (!seen["passwordauthentication"]) print "PasswordAuthentication no"
if (!seen["kbdinteractiveauthentication"]) print "KbdInteractiveAuthentication no"
if (!seen["permitrootlogin"]) print "PermitRootLogin no"
if (!seen["port"]) print "Port " port
}
BEGIN { in_global = 1 }
{
lower = tolower($0)
if (in_global && lower ~ /^[[:space:]]*match([[:space:]]|$)/) {
emit_missing()
in_global = 0
}
if (in_global && lower ~ /^[[:space:]]*pubkeyauthentication[[:space:]]+/) {
if (!seen["pubkeyauthentication"]++) print "PubkeyAuthentication yes"
next
}
if (in_global && lower ~ /^[[:space:]]*passwordauthentication[[:space:]]+/) {
if (!seen["passwordauthentication"]++) print "PasswordAuthentication no"
next
}
if (in_global && lower ~ /^[[:space:]]*kbdinteractiveauthentication[[:space:]]+/) {
if (!seen["kbdinteractiveauthentication"]++) print "KbdInteractiveAuthentication no"
next
}
if (in_global && lower ~ /^[[:space:]]*permitrootlogin[[:space:]]+/) {
if (!seen["permitrootlogin"]++) print "PermitRootLogin no"
next
}
if (in_global && lower ~ /^[[:space:]]*port[[:space:]]+/) {
if (!seen["port"]++) print "Port " port
next
}
print
}
END {
if (in_global) emit_missing()
}
' "$SSHD_CONFIG" >"$TMP_FILE"
}
if [[ $EUID -ne 0 ]]; then
die "请使用 sudo 运行，例如: sudo $0${TARGET_USER:+ --user "$TARGET_USER"}"
fi
@@ -219,13 +267,8 @@ SSHD_BIN=$(find_sshd)
SSHD_CONFIG=/etc/ssh/sshd_config
[[ -r "$SSHD_CONFIG" ]] || die "无法读取 $SSHD_CONFIG"
if ! grep -Eq '^[[:space:]]*Include[[:space:]].*sshd_config\.d' "$SSHD_CONFIG"; then
die "$SSHD_CONFIG 未包含 sshd_config.d；为避免覆盖现有规则，未作修改"
fi
DROP_IN_DIR=/etc/ssh/sshd_config.d
DROP_IN="$DROP_IN_DIR/99-dotfile-key-only.conf"
mkdir -p "$DROP_IN_DIR"
if ! sshd_already_uses_port && port_is_in_use; then
die "TCP $SSH_PORT 已被其他服务监听；请选择空闲端口后再修改脚本"
@@ -238,7 +281,7 @@ if [[ $SKIP_KEY_CHECK -eq 1 ]]; then
else
echo "已确认 $TARGET_USER 的公钥文件: $AUTHORIZED_KEYS"
fi
echo "配置文件: $DROP_IN"
echo "配置文件: $SSHD_CONFIG"
echo "若 UFW 已启用，脚本会自动放行 TCP $SSH_PORT；请确认云安全组已放行。"
if [[ $ASSUME_YES -ne 1 ]]; then
if [[ $SKIP_KEY_CHECK -eq 1 ]]; then
@@ -250,42 +293,40 @@ if [[ $ASSUME_YES -ne 1 ]]; then
fi
STAMP=$(date +%Y%m%d%H%M%S)
BACKUP=""
CONFIG_BACKUP="${SSHD_CONFIG}.bak.${STAMP}"
DROP_IN_BACKUP=""
cp -p "$SSHD_CONFIG" "$CONFIG_BACKUP"
if [[ -f "$DROP_IN" ]]; then
BACKUP="${DROP_IN}.bak.${STAMP}"
cp -p "$DROP_IN" "$BACKUP"
DROP_IN_BACKUP="/etc/ssh/sshd_config.bak.${STAMP}.dotfile-key-only.conf"
cp -p "$DROP_IN" "$DROP_IN_BACKUP"
rm -f "$DROP_IN"
fi
TMP_FILE=$(mktemp "${DROP_IN}.tmp.XXXXXX")
TMP_FILE=$(mktemp "${SSHD_CONFIG}.tmp.XXXXXX")
VALIDATION_ERROR=$(mktemp)
trap 'rm -f "$TMP_FILE" "$VALIDATION_ERROR"' EXIT
cat >"$TMP_FILE" <<'EOF'
# Managed by ~/.dotfile/script/ssh-harden.sh
PubkeyAuthentication yes
PasswordAuthentication no
KbdInteractiveAuthentication no
ChallengeResponseAuthentication no
PermitRootLogin no
Port 55522
EOF
install -m 0600 -o root -g root "$TMP_FILE" "$DROP_IN"
write_hardened_config
install -m "$(stat -c '%a' "$SSHD_CONFIG")" -o "$(stat -c '%u' "$SSHD_CONFIG")" -g "$(stat -c '%g' "$SSHD_CONFIG")" "$TMP_FILE" "$SSHD_CONFIG"
restore_drop_in() {
if [[ -n "$BACKUP" ]]; then
cp -p "$BACKUP" "$DROP_IN"
restore_config() {
cp -p "$CONFIG_BACKUP" "$SSHD_CONFIG"
if [[ -n "$DROP_IN_BACKUP" ]]; then
mkdir -p "$DROP_IN_DIR"
cp -p "$DROP_IN_BACKUP" "$DROP_IN"
else
rm -f "$DROP_IN"
fi
}
if ! ensure_ufw_port; then
restore_drop_in
restore_config
die "UFW 规则添加失败，已恢复原 SSH 配置"
fi
if ! "$SSHD_BIN" -t -f "$SSHD_CONFIG" 2>"$VALIDATION_ERROR"; then
restore_drop_in
restore_config
rollback_ufw_port
echo "sshd 配置校验输出：" >&2
cat "$VALIDATION_ERROR" >&2
@@ -293,24 +334,25 @@ if ! "$SSHD_BIN" -t -f "$SSHD_CONFIG" 2>"$VALIDATION_ERROR"; then
fi
if ! config_is_hardened; then
restore_drop_in
restore_config
rollback_ufw_port
die "新配置未成为 sshd 的生效设置（可能被更早的配置覆盖），已恢复原文件"
fi
if ! reload_sshd; then
restore_drop_in
restore_config
rollback_ufw_port
die "无法重载 ssh/sshd 服务，已恢复原文件；请检查 systemctl 状态"
fi
if ! config_is_hardened; then
restore_drop_in
restore_config
reload_sshd || true
rollback_ufw_port
die "重载后设置未生效，已恢复原文件并尝试重载旧配置"
fi
echo "已启用仅公钥 SSH 登录，已禁止 root 登录，SSH 端口已改为 $SSH_PORT。"
[[ -n "$BACKUP" ]] && echo "原配置已备份到: $BACKUP"
echo "原 SSH 配置已备份到: $CONFIG_BACKUP"
[[ -n "$DROP_IN_BACKUP" ]] && echo "旧的 dotfile SSH drop-in 已备份到: $DROP_IN_BACKUP"
echo "请保持当前会话，另开终端确认可通过密钥连接到端口 $SSH_PORT 后再退出。"