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| 1 | +#!/usr/bin/env bash |
| 2 | +# |
| 3 | +# Secure AI Appliance — Secure Boot MOK Enrollment |
| 4 | +# |
| 5 | +# Enrolls the SecAI Machine Owner Key (MOK) into the system's UEFI MOK |
| 6 | +# database. After enrollment, only kernels/bootloaders signed with this |
| 7 | +# key will be trusted. |
| 8 | +# |
| 9 | +# This script is called during firstboot. The user must reboot and |
| 10 | +# confirm enrollment in the MOK Manager (MokManager.efi) screen. |
| 11 | +# |
| 12 | +# Usage: enroll-secureboot.sh [--check-only] |
| 13 | +# |
| 14 | +set -euo pipefail |
| 15 | + |
| 16 | +MOK_DER="/etc/secure-ai/keys/secureai-mok.der" |
| 17 | +MOK_PEM="/etc/secure-ai/keys/secureai-mok.pem" |
| 18 | +STATE_FILE="/run/secure-ai/secureboot-state" |
| 19 | + |
| 20 | +log() { |
| 21 | + echo "[enroll-secureboot] $*" |
| 22 | + logger -t enroll-secureboot "$*" |
| 23 | +} |
| 24 | + |
| 25 | +write_state() { |
| 26 | + mkdir -p "$(dirname "$STATE_FILE")" 2>/dev/null || true |
| 27 | + echo "{\"secure_boot\":\"$1\",\"mok_enrolled\":\"$2\",\"detail\":\"$3\"}" > "$STATE_FILE" |
| 28 | +} |
| 29 | + |
| 30 | +check_secure_boot() { |
| 31 | + # Check if Secure Boot is enabled |
| 32 | + if [ -d /sys/firmware/efi ]; then |
| 33 | + local sb_state |
| 34 | + sb_state=$(mokutil --sb-state 2>/dev/null || echo "unknown") |
| 35 | + case "$sb_state" in |
| 36 | + *enabled*|*Enabled*) |
| 37 | + echo "enabled" |
| 38 | + return 0 |
| 39 | + ;; |
| 40 | + *disabled*|*Disabled*) |
| 41 | + echo "disabled" |
| 42 | + return 1 |
| 43 | + ;; |
| 44 | + esac |
| 45 | + fi |
| 46 | + echo "unavailable" |
| 47 | + return 1 |
| 48 | +} |
| 49 | + |
| 50 | +check_mok_enrolled() { |
| 51 | + # Check if our MOK is already enrolled |
| 52 | + if [ ! -f "$MOK_DER" ]; then |
| 53 | + return 1 |
| 54 | + fi |
| 55 | + |
| 56 | + if command -v mokutil &>/dev/null; then |
| 57 | + # Get the fingerprint of our cert |
| 58 | + local our_fp |
| 59 | + our_fp=$(openssl x509 -in "$MOK_PEM" -noout -fingerprint -sha256 2>/dev/null | \ |
| 60 | + sed 's/.*=//;s/://g' | tr '[:upper:]' '[:lower:]') |
| 61 | + |
| 62 | + # Check enrolled keys |
| 63 | + if mokutil --list-enrolled 2>/dev/null | grep -qi "$our_fp"; then |
| 64 | + return 0 |
| 65 | + fi |
| 66 | + fi |
| 67 | + return 1 |
| 68 | +} |
| 69 | + |
| 70 | +cmd_check() { |
| 71 | + echo "=== Secure Boot Status ===" |
| 72 | + |
| 73 | + local sb_state |
| 74 | + sb_state=$(check_secure_boot) |
| 75 | + echo "UEFI Secure Boot: ${sb_state}" |
| 76 | + |
| 77 | + if [ "$sb_state" = "unavailable" ]; then |
| 78 | + echo "System does not support UEFI Secure Boot." |
| 79 | + echo "This may be a legacy BIOS system or a VM without UEFI." |
| 80 | + write_state "unavailable" "false" "no_uefi" |
| 81 | + return |
| 82 | + fi |
| 83 | + |
| 84 | + if [ "$sb_state" = "disabled" ]; then |
| 85 | + echo "Secure Boot is disabled in firmware." |
| 86 | + echo "Enable it in BIOS/UEFI settings for full boot chain verification." |
| 87 | + write_state "disabled" "false" "sb_disabled" |
| 88 | + return |
| 89 | + fi |
| 90 | + |
| 91 | + # Check MOK enrollment |
| 92 | + if [ ! -f "$MOK_DER" ]; then |
| 93 | + echo "SecAI MOK certificate not found at ${MOK_DER}" |
| 94 | + echo "Run generate-mok.sh during image build to create it." |
| 95 | + write_state "enabled" "false" "no_mok_cert" |
| 96 | + return |
| 97 | + fi |
| 98 | + |
| 99 | + if check_mok_enrolled; then |
| 100 | + echo "SecAI MOK: ENROLLED" |
| 101 | + write_state "enabled" "true" "fully_configured" |
| 102 | + else |
| 103 | + echo "SecAI MOK: NOT ENROLLED" |
| 104 | + echo "Run: enroll-secureboot.sh (without --check-only) to enroll." |
| 105 | + write_state "enabled" "false" "mok_not_enrolled" |
| 106 | + fi |
| 107 | + |
| 108 | + # Check if kernel is signed |
| 109 | + if command -v sbverify &>/dev/null; then |
| 110 | + local kernel |
| 111 | + kernel=$(ls /boot/vmlinuz-* 2>/dev/null | sort -V | tail -1 || echo "") |
| 112 | + if [ -n "$kernel" ]; then |
| 113 | + if sbverify --cert "$MOK_PEM" "$kernel" 2>/dev/null; then |
| 114 | + echo "Kernel signature: VALID" |
| 115 | + else |
| 116 | + echo "Kernel signature: NOT SIGNED or INVALID" |
| 117 | + echo " The kernel may not be signed with the SecAI MOK." |
| 118 | + fi |
| 119 | + fi |
| 120 | + fi |
| 121 | + |
| 122 | + echo "=== End Secure Boot Status ===" |
| 123 | +} |
| 124 | + |
| 125 | +cmd_enroll() { |
| 126 | + log "Starting MOK enrollment..." |
| 127 | + |
| 128 | + if [ ! -f "$MOK_DER" ]; then |
| 129 | + log "ERROR: MOK certificate not found at ${MOK_DER}" |
| 130 | + log "Generate it first: /usr/libexec/secure-ai/generate-mok.sh" |
| 131 | + exit 1 |
| 132 | + fi |
| 133 | + |
| 134 | + local sb_state |
| 135 | + sb_state=$(check_secure_boot) |
| 136 | + |
| 137 | + if [ "$sb_state" = "unavailable" ]; then |
| 138 | + log "WARNING: UEFI not available. MOK enrollment skipped." |
| 139 | + write_state "unavailable" "false" "no_uefi" |
| 140 | + exit 0 |
| 141 | + fi |
| 142 | + |
| 143 | + if check_mok_enrolled; then |
| 144 | + log "SecAI MOK is already enrolled." |
| 145 | + write_state "$sb_state" "true" "already_enrolled" |
| 146 | + exit 0 |
| 147 | + fi |
| 148 | + |
| 149 | + if ! command -v mokutil &>/dev/null; then |
| 150 | + log "ERROR: mokutil not found. Install it: dnf install mokutil" |
| 151 | + exit 1 |
| 152 | + fi |
| 153 | + |
| 154 | + log "Importing MOK certificate..." |
| 155 | + log "You will be prompted for a one-time password." |
| 156 | + log "Remember this password — you'll need it on the next reboot" |
| 157 | + log "when the MOK Manager asks you to confirm enrollment." |
| 158 | + |
| 159 | + mokutil --import "$MOK_DER" |
| 160 | + |
| 161 | + log "" |
| 162 | + log "MOK import request registered." |
| 163 | + log "IMPORTANT: Reboot the system. At the MOK Manager screen:" |
| 164 | + log " 1. Select 'Enroll MOK'" |
| 165 | + log " 2. Select 'Continue'" |
| 166 | + log " 3. Enter the one-time password you just set" |
| 167 | + log " 4. Select 'Reboot'" |
| 168 | + log "" |
| 169 | + log "After reboot, the SecAI signing key will be trusted." |
| 170 | + |
| 171 | + write_state "$sb_state" "pending" "enrollment_pending_reboot" |
| 172 | +} |
| 173 | + |
| 174 | +# --- Main --- |
| 175 | +case "${1:---check-only}" in |
| 176 | + --check-only|check|status) cmd_check ;; |
| 177 | + enroll|--enroll) cmd_enroll ;; |
| 178 | + *) |
| 179 | + echo "Usage: $0 [--check-only | enroll]" |
| 180 | + exit 1 |
| 181 | + ;; |
| 182 | +esac |
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