#!/bin/bash
# Automated setup of TPM, GPG keys, and disk

set -o pipefail

## External files sourced
. /etc/functions
. /etc/luks-functions
. /tmp/config

TRACE "Under /bin/oem-factory-reset"

# use TERM to exit on error
trap "exit 1" TERM
export TOP_PID=$$

## Static local variables

CLEAR="--clear"
CONTINUE="--yes-button Continue"
CANCEL="--no-button Cancel"
HEIGHT="0"
WIDTH="80"

USER_PIN_DEF=123456
ADMIN_PIN_DEF=12345678
TPM_PASS_DEF=12345678
USER_PIN=""
ADMIN_PIN=""
TPM_PASS=""

#Circumvent Librem Key/Nitrokey HOTP firmware bug https://github.com/osresearch/heads/issues/1167
MAX_HOTP_GPG_PIN_LENGTH=25

# What are the Security components affected by custom passwords
CUSTOM_PASS_AFFECTED_COMPONENTS=""

# Default RSA key length
#TODO change it back to 3076. Canokey cannot be tested easily and Nitrokey prov1 I have doesn't key-attr to 3076
RSA_KEY_LENGTH=2048

GPG_USER_NAME="OEM Key"
GPG_KEY_NAME=$(date +%Y%m%d%H%M%S)
GPG_USER_MAIL="oem-${GPG_KEY_NAME}@example.com"
GPG_USER_COMMENT="OEM-generated key"
SKIP_BOOT="n"

## functions

die() {

    local msg=$1
    if [ -n "$msg" ]; then
        echo -e "\n$msg"
    fi
    kill -s TERM $TOP_PID
    exit 1
}

whiptail_error() {
    local msg=$1
    if [ "$msg" = "" ]; then
        die "whiptail error: An error msg is required"
    fi
    whiptail $BG_COLOR_ERROR --msgbox "${msg}\n\n" $HEIGHT $WIDTH $BG_COLOR_ERROR --title "Error"
}

whiptail_error_die() {
    whiptail_error "$@"
    die
}

#Generate a gpg master key: passwordless, no expiration date, RSA 4096 bits
#This key will be used to sign 3 subkeys: encryption, authentication and signing
#The master key will be stored on the disk, and the subkeys on the smartcard
generate_inmemory_RSA_master_and_subkeys() {
    TRACE "Under oem-factory-reset:generate_inmemory_RSA_master_and_subkeys"
    echo "Generating GPG key material in memory:"

    echo "Generating GPG RSA ${RSA_KEY_LENGTH} bits master key..."
    # Generate GPG master key
    {
        echo "Key-Type: RSA"
        echo "Key-Length: ${RSA_KEY_LENGTH}"
        echo "Key-Usage: sign"
        echo "Name-Real: ${GPG_USER_NAME}"
        echo "Name-Comment: ${GPG_USER_COMMENT}"
        echo "Name-Email: ${GPG_USER_MAIL}"
        echo "Expire-Date: 0"
        echo "Passphrase: ${ADMIN_PIN}"
        echo "%commit"
    } | gpg --batch --gen-key \
        >/tmp/gpg_card_edit_output 2>&1
    if [ $? -ne 0 ]; then
        ERROR=$(cat /tmp/gpg_card_edit_output)
        whiptail_error_die "GPG Key generation failed!\n\n$ERROR"
    fi

    echo "Generating GPG RSA ${RSA_KEY_LENGTH} bits signing subkey..."
    # Add signing subkey
    {
        echo addkey
        echo 4 # RSA (sign only)
        echo ${RSA_KEY_LENGTH}
        echo 0 # no expiration
        echo ${ADMIN_PIN}
        echo y # confirm
        echo save
    } | gpg --command-fd=0 --status-fd=1 --pinentry-mode=loopback --edit-key "${GPG_USER_MAIL}" \
        >/tmp/gpg_card_edit_output 2>&1
    if [ $? -ne 0 ]; then
        ERROR=$(cat /tmp/gpg_card_edit_output)
        whiptail_error_die "GPG Key signing subkey generation failed!\n\n$ERROR"
    fi

    echo "Generating GPG RSA ${RSA_KEY_LENGTH} bits encryption subkey..."
    #Add encryption subkey
    {
        echo addkey
        echo 6 # RSA (encrypt only)
        echo ${RSA_KEY_LENGTH}
        echo 0 # no expiration
        echo ${ADMIN_PIN}
        echo y # confirm
        echo save
    } | gpg --command-fd=0 --status-fd=1 --pinentry-mode=loopback --edit-key "${GPG_USER_MAIL}" \
        >/tmp/gpg_card_edit_output 2>&1
    if [ $? -ne 0 ]; then
        ERROR=$(cat /tmp/gpg_card_edit_output)
        whiptail_error_die "GPG Key encryption subkey generation failed!\n\n$ERROR"
    fi

    echo "Generating GPG RSA ${RSA_KEY_LENGTH} bits authentication subkey..."
    #Add authentication subkey
    {
        #Authentication subkey needs gpg in expert mode to select RSA custom mode (8)
        # in order to disable encryption and signing capabilities of subkey
        # and then enable authentication capability
        echo addkey
        echo 8 # RSA (own capabilite)
        echo S # disable signing capability
        echo E # disable encryption capability
        echo A # enable authentication capability
        echo Q # quit
        echo ${RSA_KEY_LENGTH}
        echo 0 # no expiration
        echo ${ADMIN_PIN}
        echo y # confirm
        echo save
    } | gpg --command-fd=0 --status-fd=1 --pinentry-mode=loopback --expert --edit-key "${GPG_USER_MAIL}" \
        >/tmp/gpg_card_edit_output 2>&1
    if [ $? -ne 0 ]; then
        ERROR=$(cat /tmp/gpg_card_edit_output)
        whiptail_error_die "GPG Key authentication subkey generation failed!\n\n$ERROR"
    fi

    DEBUG "Setting public key to ultimate trust..."
    #Set the public key to the ultimate trust
    {
        echo trust
        echo 5 # ultimate
        echo y # confirm
        echo save
    } | gpg --command-fd=0 --status-fd=1 --pinentry-mode=loopback --edit-key "${GPG_USER_MAIL}" \
        >/tmp/gpg_card_edit_output 2>&1
    if [ $? -ne 0 ]; then
        ERROR=$(cat /tmp/gpg_card_edit_output)
        whiptail_error_die "GPG Key setting public key to ultimate trust failed!\n\n$ERROR"
    fi
}

#Function to move current gpg keyring subkeys to card (keytocard)
# This is aimed to be used after having generated master key and subkeys in memory and having backuped them to a LUKS container
# This function will keytocard the subkeys from the master key in the keyring
# The master key will be kept in the keyring
# The master key was already used to sign the subkeys, so it is not needed anymore
# Delete the master key from the keyring once key to card is done (already backuped on LUKS private partition)
keytocard_subkeys_to_smartcard() {
    TRACE "Under oem-factory-reset:keytocard_subkeys_to_smartcard"

    #make sure usb ready and usb dongle ready to communicate with
    enable_usb
    enable_usb_storage
    gpg --card-status >/dev/null 2>&1 || die "Error getting GPG card status"

    DEBUG "Factory resetting the smartcard..."
    gpg_key_factory_reset

    DEBUG "Moving subkeys to smartcard..."

    #keytocard all subkeys
    {
        echo "key 1" #Select Signature key
        echo "keytocard"
        echo "1"          # Signature key
        echo "$ADMIN_PIN" #Smartcard admin pin
        echo "$ADMIN_PIN" #Subkey PIN
        echo "0"          #No expiration date
        echo "key 1"
        echo "key 2"
        echo "keytocard"
        echo "2" # Encryption key
        echo "$ADMIN_PIN"
        echo "$ADMIN_PIN"
        echo "key 2"
        echo "key 3"
        echo "keytocard"
        echo "3" # Authentication key
        echo "$ADMIN_PIN"
        echo "$ADMIN_PIN"
        echo "key 3"
        echo "save"
    } | gpg --command-fd=0 --status-fd=1 --pinentry-mode=loopback --expert --edit-key "${GPG_USER_MAIL}" \
        >/tmp/gpg_card_edit_output 2>&1
    if [ $? -ne 0 ]; then
        ERROR=$(cat /tmp/gpg_card_edit_output)
        whiptail_error_die "GPG Key moving subkeys to smartcard failed!\n\n$ERROR"
    fi
    DEBUG "Moving subkeys to smartcard done."
}

#Whiptail prompt to disconnect any external USB storage device
prompt_disconnect_external_USB_storage_device() {
    TRACE "Under oem-factory-reset:disconnect_external_USB_storage_device"
    #Whiptail $BG_COLOR_WARNING warning about removing any external USB storage device currently connected
    whiptail $BG_COLOR_WARNING --title 'WARNING: Please disconnect any external USB storage device' \
        --msgbox "An external USB storage device will be WIPED next.\n\nPlease disconnect all external USB storage devices." 0 80 ||
        die "Error displaying warning about removing any external USB storage device currently connected"

}

#Whiptail prompt to insert to be wiped thumb drive
prompt_insert_to_be_wiped_thumb_drive() {
    TRACE "Under oem-factory-reset:prompt_insert_to_be_wiped_thumb_drive"
    #Whiptail warning about having only desired to be wiped thumb drive inserted
    whiptail $BG_COLOR_WARNING --title 'WARNING: Please insert the thumb drive to be wiped' \
        --msgbox "The thumb drive will be WIPED next.\n\nPlease have connected only the thumb drive to be wiped." 0 80 ||
        die "Error displaying warning about having only desired to be wiped thumb drive inserted"
}

#list blkid devices (removing partition numbers)
list_blkid_devices() {
    TRACE "Under oem-factory-reset:list_blkid_devices"
    blkid | cut -d: -f1 | sed 's/[0-9]$//'
}

#export master key and subkeys to thumbdrive's private LUKS contained partition
export_master_key_subkeys_and_revocation_key_to_private_LUKS_container() {
    TRACE "Under oem-factory-reset:export_master_key_subkeys_and_revocation_key_to_private_LUKS_container"

    #Sanity check on passed arguments
    while [ $# -gt 0 ]; do
        case "$1" in
        --mode)
            mode="$2"
            shift
            shift
            ;;
        --device)
            device="$2"
            shift
            shift
            ;;
        --mountpoint)
            mountpoint="$2"
            shift
            shift
            ;;
        --pass)
            pass="$2"
            shift
            shift
            ;;
        *)
            die "Error: unknown argument: $1"
            ;;
        esac
    done

    mount-usb --mode "$mode" --device "$device" --mountpoint "$mountpoint" --pass "$pass" || die "Error mounting thumb drive's private partition"

    #Export master key and subkeys to thumb drive
    DEBUG "Exporting master key and subkeys to private LUKS container's partition..."
    gpg --export-secret-key --armor --pinentry-mode loopback --passphrase-file <(echo -n "${pass}") "${GPG_USER_MAIL}" >"$mountpoint"/privkey.sec ||
        die "Error exporting master key to private LUKS container's partition"
    gpg --export-secret-subkeys --armor --pinentry-mode loopback --passphrase-file <(echo -n "${pass}") "${GPG_USER_MAIL}" >"$mountpoint"/subkeys.sec ||
        die "Error exporting subkeys to private LUKS container's partition"
    #copy whole keyring to thumb drive, including revocation key and trust database
    cp -af ~/.gnupg "$mountpoint"/.gnupg || die "Error copying whole keyring to private LUKS container's partition"
    #Unmount private LUKS container's mount point
    umount "$mountpoint" || die "Error unmounting private LUKS container's mount point"
}

#Export public key to thumb drive's public partition
export_public_key_to_thumbdrive_public_partition() {
    TRACE "Under oem-factory-reset:export_public_key_to_thumbdrive_public_partition"

    #Sanity check on passed arguments
    while [ $# -gt 0 ]; do
        case "$1" in
        --mode)
            mode="$2"
            shift
            shift
            ;;
        --device)
            device="$2"
            shift
            shift
            ;;
        --mountpoint)
            mountpoint="$2"
            shift
            shift
            ;;
        *)
            die "Error: unknown argument: $1"
            ;;
        esac
    done

    #pass non-empty arguments to --pass, --mountpoint, --device, --mode
    mount-usb --device "$device" --mode "$mode" --mountpoint "$mountpoint" || die "Error mounting thumb drive's public partition"

    gpg --export --armor "${GPG_USER_MAIL}" >"$mountpoint"/pubkey.asc || die "Error exporting public key to thumb drive's public partition"

    umount "$mountpoint" || die "Error unmounting thumb drive's public partition"
}

#Wipe a thumb drive and export master key and subkeys to it
wipe_thumb_drive_and_copy_gpg_key_material() {
    TRACE "Under oem-factory-reset:wipe_thumb_drive_and_copy_gpg_key_material"
    prompt_disconnect_external_USB_storage_device
    actual_devices=$(list_blkid_devices)
    #enable usb storage
    enable_usb
    enable_usb_storage
    prompt_insert_to_be_wiped_thumb_drive
    new_devices=$(list_blkid_devices)
    thumb_drive=$(echo "$new_devices" | grep -v "$actual_devices" | uniq)
    if [ -z "$thumb_drive" ]; then
        whiptail_error_die "No new thumb drive detected! Aborting."
    fi
    select_luks_container_size_percent
    #Wipe thumb drive with a LUKS container of size $(cat /tmp/luks_container_size_percent)
    prepare_thumb_drive --device "$thumb_drive" --percentage "$(cat /tmp/luks_container_size_percent)" --pass "$ADMIN_PIN"
    #Export master key and subkeys to thumb drive first partition
    export_master_key_subkeys_and_revocation_key_to_private_LUKS_container --mode rw --device "$thumb_drive"1 --mountpoint /media --pass "$ADMIN_PIN"
    #Export public key to thumb drive's public partition
    export_public_key_to_thumbdrive_public_partition --mode rw --device "$thumb_drive"2 --mountpoint /media
}

gpg_key_factory_reset() {
    TRACE "Under oem-factory-reset:gpg_key_factory_reset"

    #enable usb storage
    enable_usb

    # Factory reset GPG card
    DEBUG "GPG factory reset..."
    {
        echo admin
        echo factory-reset
        echo y
        echo yes
    } | gpg --command-fd=0 --status-fd=1 --pinentry-mode=loopback --card-edit \
        >/tmp/gpg_card_edit_output 2>&1
    if [ $? -ne 0 ]; then
        ERROR=$(cat /tmp/gpg_card_edit_output)
        whiptail_error_die "GPG Key factory reset failed!\n\n$ERROR"
    fi
    # If Nitrokey Storage is inserted, reset AES keys as well
    if lsusb | grep -q "20a0:4109" && [ -x /bin/hotp_verification ]; then
        /bin/hotp_verification regenerate ${ADMIN_PIN_DEF}
    fi
    # Toggle forced sig (good security practice, forcing PIN request for each signature request)
    if gpg --card-status | grep "Signature PIN" | grep -q "not forced"; then
        DEBUG "GPG toggling forcesig on since off..."
        {
            echo admin
            echo forcesig
            echo ${ADMIN_PIN_DEF}
        } | gpg --command-fd=0 --status-fd=1 --pinentry-mode=loopback --card-edit \
            >/tmp/gpg_card_edit_output 2>&1
        if [ $? -ne 0 ]; then
            ERROR=$(cat /tmp/gpg_card_edit_output)
            whiptail_error_die "GPG Key forcesig toggle on failed!\n\n$ERROR"
        fi
    fi
    # use p256 for key generation if requested
    if [ "$GPG_ALGO" = "p256" ]; then
        {
            echo admin
            echo key-attr
            echo 2 # ECC
            echo 3 # P-256
            echo ${ADMIN_PIN_DEF}
            echo 2 # ECC
            echo 3 # P-256
            echo ${ADMIN_PIN_DEF}
            echo 2 # ECC
            echo 3 # P-256
            echo ${ADMIN_PIN_DEF}
        } | gpg --command-fd=0 --status-fd=1 --pinentry-mode=loopback --card-edit --expert \
            >/tmp/gpg_card_edit_output 2>&1
        if [ $? -ne 0 ]; then
            ERROR=$(cat /tmp/gpg_card_edit_output)
            whiptail_error_die "Setting key to NIST-P256 in USB security dongle failed."
        fi
    # fallback to RSA key generation by default
    else
        DEBUG "GPG setting RSA key length to ${RSA_KEY_LENGTH} bits..."
        # Set RSA key length
        {
            echo admin
            echo key-attr
            echo 1                 # RSA
            echo ${RSA_KEY_LENGTH} #Signing key size set to RSA_KEY_LENGTH
            echo ${ADMIN_PIN_DEF}
            echo 1                 # RSA
            echo ${RSA_KEY_LENGTH} #Encryption key size set to RSA_KEY_LENGTH
            echo ${ADMIN_PIN_DEF}
            echo 1                 # RSA
            echo ${RSA_KEY_LENGTH} #Authentication key size set to RSA_KEY_LENGTH
            echo ${ADMIN_PIN_DEF}
        } | gpg --command-fd=0 --status-fd=1 --pinentry-mode=loopback --card-edit \
            >/tmp/gpg_card_edit_output 2>&1
        if [ $? -ne 0 ]; then
            ERROR=$(cat /tmp/gpg_card_edit_output)
            whiptail_error_die "Setting key attributed to RSA ${RSA_KEY_LENGTH} bits in USB security dongle failed."
        fi
    fi
}

generate_OEM_gpg_keys() {
    # Generate OEM GPG keys
    TRACE "Under oem-factory-reset:generate_OEM_gpg_keys"
    DEBUG "Generating GPG keys to RSA ${RSA_KEY_LENGTH} bits in smartcard..."
    {
        echo admin
        echo generate
        echo n
        echo ${ADMIN_PIN_DEF}
        echo ${USER_PIN_DEF}
        echo 0
        echo ${GPG_USER_NAME}
        echo ${GPG_USER_MAIL}
        echo ${GPG_USER_COMMENT}
        echo ${USER_PIN_DEF}
    } | gpg --command-fd=0 --status-fd=2 --pinentry-mode=loopback --card-edit \
        >/tmp/gpg_card_edit_output 2>&1
    if [ $? -ne 0 ]; then
        ERROR=$(cat /tmp/gpg_card_edit_output)
        whiptail_error_die "GPG Key automatic keygen failed!\n\n$ERROR"
    fi
}

gpg_key_change_pin() {
    TRACE "Under oem-factory-reset:gpg_key_change_pin"
    DEBUG "Changing GPG key PINs..."
    # 1 = user PIN, 3 = admin PIN
    PIN_TYPE=$1
    PIN_ORIG=$2
    PIN_NEW=$3
    # Change PIN
    {
        echo admin
        echo passwd
        echo ${PIN_TYPE}
        echo ${PIN_ORIG}
        echo ${PIN_NEW}
        echo ${PIN_NEW}
        echo q
        echo q
    } | gpg --command-fd=0 --status-fd=2 --pinentry-mode=loopback --card-edit \
        >/tmp/gpg_card_edit_output 2>&1
    if [ $? -ne 0 ]; then
        ERROR=$(cat /tmp/gpg_card_edit_output | fold -s)
        whiptail_error_die "GPG Key PIN change failed!\n\n$ERROR"
    fi
}

generate_checksums() {
    TRACE "Under oem-factory-reset:generate_checksums"
    # ensure /boot mounted
    if ! grep -q /boot /proc/mounts; then
        mount -o rw /boot || whiptail_error_die "Unable to mount /boot"
    else
        mount -o remount,rw /boot || whiptail_error_die "Unable to mount /boot"
    fi

    #Check if previous TPM Disk unlock Key was set
    if [ -e /boot/kexec_key_devices.txt ]; then
        TPM_DISK_ENCRYPTION_KEY_SET=1
    fi

    # clear any existing checksums/signatures
    rm /boot/kexec* 2>/dev/null

    # create Heads TPM counter
    if [ "$CONFIG_TPM" = "y" ]; then
        if [ "$CONFIG_IGNORE_ROLLBACK" != "y" ]; then
            tpmr counter_create \
                -pwdo "$TPM_PASS" \
                -pwdc '' \
                -la -3135106223 |
                tee /tmp/counter ||
                whiptail_error_die "Unable to create TPM counter"
            TPM_COUNTER=$(cut -d: -f1 </tmp/counter)

            # increment TPM counter
            increment_tpm_counter $TPM_COUNTER >/dev/null 2>&1 ||
                whiptail_error_die "Unable to increment tpm counter"

            # create rollback file
            sha256sum /tmp/counter-$TPM_COUNTER >/boot/kexec_rollback.txt 2>/dev/null ||
                whiptail_error_die "Unable to create rollback file"
        else
            ## needs to exist for initial call to unseal-hotp
            echo "0" >/boot/kexec_hotp_counter
        fi
    fi

    # set default boot option only if no TPM Disk Unlock Key previously set
    if [ -z "$TPM_DISK_ENCRYPTION_KEY_SET" ]; then
        set_default_boot_option
    fi

    # generate hashes
    (
        set -e -o pipefail
        cd /boot
        find ./ -type f ! -path './kexec*' -print0 |
            xargs -0 sha256sum >/boot/kexec_hashes.txt 2>/dev/null
        print_tree >/boot/kexec_tree.txt
    )
    [ $? -eq 0 ] || whiptail_error_die "Error generating kexec hashes"

    param_files=$(find /boot/kexec*.txt)
    [ -z "$param_files" ] &&
        whiptail_error_die "No kexec parameter files to sign"

    # sign kexec boot files
    if sha256sum $param_files 2>/dev/null | gpg \
        --pinentry-mode loopback \
        --passphrase "$USER_PIN" \
        --digest-algo SHA256 \
        --detach-sign \
        -a \
        >/boot/kexec.sig 2>/tmp/error; then
        # successful - update the validated params
        if ! check_config /boot >/dev/null 2>/tmp/error; then
            cat /tmp/error
            ret=1
        else
            ret=0
        fi
    else
        cat /tmp/error
        ret=1
    fi

    # done writing to /boot, switch back to RO
    mount -o ro,remount /boot

    if [ $ret = 1 ]; then
        ERROR=$(tail -n 1 /tmp/error | fold -s)
        whiptail_error_die "Error signing kexec boot files:\n\n$ERROR"
    fi
}

set_default_boot_option() {
    TRACE "Under oem-factory-reset:set_default_boot_option"
    option_file="/tmp/kexec_options.txt"
    tmp_menu_file="/tmp/kexec/kexec_menu.txt"
    hash_file="/boot/kexec_default_hashes.txt"

    mkdir -p /tmp/kexec/
    rm $option_file 2>/dev/null
    # parse boot options from grub.cfg
    for i in $(find /boot -name "grub.cfg"); do
        kexec-parse-boot "/boot" "$i" >>$option_file
    done
    # FC29/30+ may use BLS format grub config files
    # https://fedoraproject.org/wiki/Changes/BootLoaderSpecByDefault
    # only parse these if $option_file is still empty
    if [ ! -s $option_file ] && [ -d "/boot/loader/entries" ]; then
        for i in $(find /boot -name "grub.cfg"); do
            kexec-parse-bls "/boot" "$i" "/boot/loader/entries" >>$option_file
        done
    fi
    [ ! -s $option_file ] &&
        whiptail_error_die "Failed to parse any boot options"

    # sort boot options
    sort -r $option_file | uniq >$tmp_menu_file

    ## save first option as default
    entry=$(head -n 1 $tmp_menu_file | tail -1)

    # clear existing default configs
    rm "/boot/kexec_default.*.txt" 2>/dev/null

    # get correct index for entry
    index=$(grep -n "$entry" $option_file | cut -f1 -d ':')

    # write new config
    echo "$entry" >/boot/kexec_default.$index.txt

    # validate boot option
    (cd /boot && /bin/kexec-boot -b "/boot" -e "$entry" -f |
        xargs sha256sum >$hash_file 2>/dev/null) ||
        whiptail_error_die "Failed to create hashes of boot files"
}

report_integrity_measurements() {
    TRACE "Under oem-factory-reset:report_integrity_measurements"
    #check for GPG key in keyring
    GPG_KEY_COUNT=$(gpg -k 2>/dev/null | wc -l)
    if [ "$GPG_KEY_COUNT" -ne 0 ]; then
        # Check and report TOTP
        # update the TOTP code every thirty seconds
        date=$(date "+%Y-%m-%d %H:%M:%S %Z")
        seconds=$(date "+%s")
        half=$(expr \( "$seconds" % 60 \) / 30)
        if [ "$CONFIG_TPM" != "y" ]; then
            TOTP="NO TPM"
        elif [ "$half" != "$last_half" ]; then
            last_half=$half
            TOTP=$(unseal-totp) >/dev/null 2>&1
        fi

        # Check and report on HOTP status
        if [ -x /bin/hotp_verification ]; then
            HOTP=$(unseal-hotp) >/dev/null 2>&1
            enable_usb
            if ! hotp_verification info >/dev/null 2>&1; then
                whiptail $CONFIG_WARNING_BG_COLOR --title 'WARNING: Please insert your HOTP enabled USB Security dongle' --msgbox "Your HOTP enabled USB Security dongle was not detected.\n\nPlease remove it and insert it again." 0 80
            fi
            # Don't output HOTP codes to screen, so as to make replay attacks harder
            hotp_verification check $HOTP
            case "$?" in
            0)
                HOTP="Success"
                ;;
            4)
                HOTP="Invalid code"
                MAIN_MENU_BG_COLOR=$CONFIG_ERROR_BG_COLOR
                ;;
            *)
                HOTP="Error checking code, Insert USB Security dongle and retry"
                MAIN_MENU_BG_COLOR=$CONFIG_WARNING_BG_COLOR
                ;;
            esac
        else
            HOTP='N/A'
        fi
        # Check for detached signed digest and report on /boot integrity status
        check_config /boot force
        TMP_HASH_FILE="/tmp/kexec/kexec_hashes.txt"

        if (cd /boot && sha256sum -c "$TMP_HASH_FILE" >/tmp/hash_output); then
            HASH="OK"
        else
            HASH="ALTERED"
        fi

        #Show results
        whiptail $MAIN_MENU_BG_COLOR --title "Measured Integrity Report" --msgbox "$date\nTOTP: $TOTP | HOTP: $HOTP\n/BOOT INTEGRITY: $HASH\n\nPress OK to continue or Ctrl+Alt+Delete to reboot" 0 80
    fi
}

usb_security_token_capabilities_check() {
    TRACE "Under /bin/oem-factory-reset:usb_security_token_capabilities_check"

    enable_usb
    # ... first set board config preference
    if [ -n "$CONFIG_GPG_ALGO" ]; then
        GPG_ALGO=$CONFIG_GPG_ALGO
        DEBUG "Setting GPG_ALGO to (board-)configured: $CONFIG_GPG_ALGO"
    fi
    # ... overwrite with usb-token capability
    #TODO: revert. Testing test firmware for Nitrokey 3 which is supposed to support RSA 3076 now
    #if lsusb | grep -q "20a0:42b2"; then
    #    GPG_ALGO="p256"
    #    DEBUG "Nitrokey 3 detected: Setting GPG_ALGO to: $GPG_ALGO"
    #fi
}

## main script start

# check for args
if [ "$1" != "" ]; then
    title_text=$1
else
    title_text="OEM Factory Reset / Re-Ownership"
fi
if [ "$2" != "" ]; then
    bg_color=$2
else
    bg_color=""
fi

# show warning prompt
if [ "$CONFIG_TPM" = "y" ]; then
    TPM_STR="          * ERASE the TPM and own it with a password\n"
else
    TPM_STR=""
fi
if ! whiptail --yesno "
        This operation will automatically:\n
$TPM_STR
          * ERASE any keys or passwords on the GPG smart card,\n
            reset it to a factory state, generate new keys\n
            and optionally set custom PIN(s)\n
          * Add the new GPG key to the firmware and reflash it\n
          * Sign all of the files in /boot with the new GPG key\n\n
        It requires that you already have an OS installed on a\n
        dedicated /boot partition. Do you wish to continue?" \
    $HEIGHT $WIDTH $CONTINUE $CANCEL $CLEAR $bg_color --title "$title_text"; then
    exit 1
fi

# We show current integrity measurements status and time
report_integrity_measurements

# Determine gpg algorithm to be used, based on available usb-token
usb_security_token_capabilities_check

use_defaults=n
if [ "$CONFIG_OEMRESET_OFFER_DEFAULTS" = y ]; then
    echo -e -n "Would you like to use default configuration options?\nIf N, you will be prompted for each option [Y/n]: "
    read -n 1 use_defaults
fi

if [ "$use_defaults" == "n" -o "$use_defaults" == "N" ]; then
    #Give general guidance to user on how to answer prompts
    echo "The following questionnaire will help you to configure the security components of your system."
    echo "You will be prompted for each option to answer a single letter at prompts (Y/n/m)."
    echo "If you don't know what to answer, just press Enter to use default value which is shown between [] brackets as the uppercase letter."

    # Re-ownership of encrypted disk key, content and passphrase
    echo -e -n "\n\nWould you like to change the current LUKS Disk Recovery Key passphrase?\n (Highly recommended if you didn't install the Operating System yourself, so that past provisioned passphrase would not permit to access content.\n  Note that without re-encrypting disk, a backuped header could be restored to access encrypted content with old passphrase) [y/N]: "
    read -n 1 prompt_output
    echo
    if [ "$prompt_output" == "y" \
        -o "$prompt_output" == "Y" ]; then
        luks_new_Disk_Recovery_Key_passphrase_desired=1
        echo -e "\n"
    fi

    echo -e -n "Would you like to re-encrypt LUKS encrypted container and generate new Disk Recovery key?\n (Highly recommended if you didn't install the operating system yourself: this would prevent any LUKS backuped header to be restored to access encrypted data) [y/N]: "
    read -n 1 prompt_output
    echo
    if [ "$prompt_output" == "y" \
        -o "$prompt_output" == "Y" ]; then
        test_luks_current_disk_recovery_key_passphrase
        luks_new_Disk_Recovery_Key_desired=1
        echo -e "\n"
    fi

    #Prompt to ask if user wants to generate GPG key material in memory or on smartcard
    echo -e -n "Would you like to generate GPG key material in (m)emory or (S)olely on the security element of the USB security dongle? [m/S]: "
    read -n 1 prompt_output
    echo
    if [ "$prompt_output" == "m" \
        -o "$prompt_output" == "M" ] \
        ; then
        GPG_GEN_KEY_IN_MEMORY=1
        #TODO: present steps clearer for user
        echo "Master key and subkeys will be generated in memory, backuped to dedicated LUKS container and then subkeys imported to factory resetted smartcard."
    else
        GPG_GEN_KEY_IN_MEMORY=0
    fi

    # TODO: add LUKS container passphrase = ADMIN_PIN in security components provisioned
    # Adapt message to be given to user in terms of security components that will be applied.
    if [ -n "$luks_new_Disk_Recovery_Key_passphrase_desired" -o -n "$luks_new_Disk_Recovery_Key_passphrase" ]; then
        CUSTOM_PASS_AFFECTED_COMPONENTS="LUKS Disk Recovery Key passphrase"
    fi
    if [ "$CONFIG_TPM" = "y" ]; then
        CUSTOM_PASS_AFFECTED_COMPONENTS="$CUSTOM_PASS_AFFECTED_COMPONENTS
TPM Owner Password"
    fi
    CUSTOM_PASS_AFFECTED_COMPONENTS="$CUSTOM_PASS_AFFECTED_COMPONENTS
GPG Admin PIN
GPG User PIN"

    # Inform user of security components affected for the following prompts
    echo -e "The following security components will be provisioned with defaults or chosen PINs/passwords:
	$CUSTOM_PASS_AFFECTED_COMPONENTS\n"

    # Prompt to change default passwords
    echo -e -n "Would you like to set a single custom password that will be provisioned to previously stated security components? [y/N]: "
    read -n 1 prompt_output
    echo
    if [ "$prompt_output" == "y" \
        -o "$prompt_output" == "Y" ]; then
        echo -e "\nThe chosen custom password must be between 8 and $MAX_HOTP_GPG_PIN_LENGTH characters in length.\n"
        echo
        while [[ ${#CUSTOM_SINGLE_PASS} -lt 8 ]] || [[ ${#CUSTOM_SINGLE_PASS} -gt $MAX_HOTP_GPG_PIN_LENGTH ]]; do
            echo -e -n "Enter the custom password: "
            read CUSTOM_SINGLE_PASS
        done
        echo
        TPM_PASS=$CUSTOM_SINGLE_PASS
        USER_PIN=$CUSTOM_SINGLE_PASS
        ADMIN_PIN=$CUSTOM_SINGLE_PASS

        # Only set if user said desired. Matches rest of logic
        if [ -n "$luks_new_Disk_Recovery_Key_passphrase_desired" ]; then
            luks_new_Disk_Recovery_Key_passphrase=$CUSTOM_SINGLE_PASS
        fi
    else
        echo -e -n "Would you like to set distinct PINs/passwords to be provisioned to previously stated security components? [y/N]: "
        read -n 1 prompt_output
        echo
        if [ "$prompt_output" == "y" \
            -o "$prompt_output" == "Y" ]; then
            echo -e "\nThey must be each at least 8 characters in length.\n"
            echo
            if [ "$CONFIG_TPM" = "y" ]; then
                while [[ ${#TPM_PASS} -lt 8 ]]; do
                    echo -e -n "Enter desired TPM Owner Password: "
                    read TPM_PASS
                done
            fi
            while [[ ${#ADMIN_PIN} -lt 8 ]] || [[ ${#ADMIN_PIN} -gt $MAX_HOTP_GPG_PIN_LENGTH ]]; do
                echo -e -n "\nThis PIN should be between 8 to $MAX_HOTP_GPG_PIN_LENGTH characters in length.\n"
                echo -e -n "Enter desired GPG Admin PIN: "
                read ADMIN_PIN
            done
            while [[ ${#USER_PIN} -lt 8 ]] || [[ ${#USER_PIN} -gt 64 ]]; do
                echo -e -n "\nThis PIN should be between 8 to 64 characters in length.\n"
                echo -e -n "Enter desired GPG User PIN: "
                read USER_PIN
            done
            echo
        fi
    fi

    if [ -n "$luks_new_Disk_Recovery_Key_passphrase_desired" -a -z "$luks_new_Disk_Recovery_Key_passphrase" ]; then
        # We catch here if changing LUKS Disk Recovery Key passphrase was desired
        #  but yet undone. This is if not being covered by the single password
        echo -e "\nEnter desired replacement for current Disk Recovery Key passphrase (At least 8 characters long):"
        while [[ ${#luks_new_Disk_Recovery_Key_passphrase} -lt 8 ]]; do
            {
                read -r luks_new_Disk_Recovery_Key_passphrase
            }
        done
        #We test that current Disk Recovery Key passphrase is known prior of going further
        test_luks_current_disk_recovery_key_passphrase
        echo -e "\n"
    fi

    # Prompt to change default GnuPG key information
    echo -e -n "Would you like to set custom user information for the GnuPG key? [y/N]: "
    read -n 1 prompt_output
    echo
    if [ "$prompt_output" == "y" \
        -o "$prompt_output" == "Y" ]; then
        echo -e "\n\n"
        echo -e "We will generate a GnuPG (PGP) keypair identifiable with the following text form:"
        echo -e "Real Name (Comment) email@address.org"

        echo -e "\nEnter your Real Name (Optional):"
        read -r GPG_USER_NAME

        echo -e "\nEnter your email@adress.org:"
        read -r GPG_USER_MAIL
        while ! $(expr "$GPG_USER_MAIL" : '.*@' >/dev/null); do
            {
                echo -e "\nEnter your email@address.org:"
                read -r GPG_USER_MAIL
            }
        done

        echo -e "\nEnter Comment (Optional, to distinguish this key from others with same previous attributes. Must be smaller then 60 characters):"
        read -r GPG_USER_COMMENT
        while [[ ${#GPG_USER_COMMENT} -gt 60 ]]; do
            {
                echo -e "\nEnter Comment (Optional, to distinguish this key from others with same previous attributes. Must be smaller then 60 characters):"
                read -r GPG_USER_COMMENT
            }
        done
    fi
fi

# If nothing is stored in custom variables, we set them to their defaults
if [ "$TPM_PASS" == "" ]; then TPM_PASS=$TPM_PASS_DEF; fi
if [ "$USER_PIN" == "" ]; then USER_PIN=$USER_PIN_DEF; fi
if [ "$ADMIN_PIN" == "" ]; then ADMIN_PIN=$ADMIN_PIN_DEF; fi

## sanity check the USB, GPG key, and boot device before proceeding further

if [ "$GPG_GEN_KEY_IN_MEMORY" == "0" ]; then
    # Prompt to insert USB drive if desired
    echo -e -n "\nWould you like to export your public key to an USB drive? [y/N]: "
    read -n 1 prompt_output
    echo
    if [ "$prompt_output" == "y" \
        -o "$prompt_output" == "Y" ] \
        ; then
        GPG_EXPORT=1
        # mount USB over /media only if not already mounted
        if ! grep -q /media /proc/mounts; then
            # mount USB in rw
            if ! mount-usb --mode rw 2>/tmp/error; then
                ERROR=$(tail -n 1 /tmp/error | fold -s)
                whiptail_error_die "Unable to mount USB on /media:\n\n${ERROR}"
            fi
        else
            #/media already mounted, make sure it is in r+w mode
            if ! mount -o remount,rw /media 2>/tmp/error; then
                ERROR=$(tail -n 1 /tmp/error | fold -s)
                whiptail_error_die "Unable to remount in read+write USB on /media:\n\n${ERROR}"
            fi
        fi
    else
        GPG_EXPORT=0
        # needed for USB Security dongle below and is ensured via mount-usb in case of GPG_EXPORT=1
        enable_usb
    fi
fi

# ensure USB Security Dongle connected if GPG_GEN_KEY_IN_MEMORY=0
if [ "$GPG_GEN_KEY_IN_MEMORY" == "0" ]; then
    echo -e "\nChecking for USB Security Dongle...\n"
    enable_usb
    if ! gpg --card-status >/dev/null 2>&1; then
        whiptail_error "Can't access USB Security Dongle; \nPlease remove and reinsert, then press Enter."
        if ! gpg --card-status >/dev/null 2>/tmp/error; then
            ERROR=$(tail -n 1 /tmp/error | fold -s)
            whiptail_error_die "Unable to detect USB Security Dongle:\n\n${ERROR}"
        fi
    fi
fi

assert_signable

# Action time...

#TODO: Should we replace text from "Add a new GPG key" to "Replace current GPG key"? Should we wipe current keyring?
#Current logic is for factory reset, where re-ownership adds key to the keyring which is then copied over cbfs.
# In the all case, we should wipe the keyring since otherwise, USB security dongle is wiped but not the keyring which exposes past public keys
#  this seems wrong
# clear local keyring
rm /.gnupg/* | true


# detect and set /boot device
echo -e "\nDetecting and setting boot device...\n"
if ! detect_boot_device; then
    SKIP_BOOT="y"
else
    echo -e "Boot device set to $CONFIG_BOOT_DEV\n"
fi

# update configs
if [[ "$SKIP_BOOT" == "n" ]]; then
    replace_config /etc/config.user "CONFIG_BOOT_DEV" "$CONFIG_BOOT_DEV"
    combine_configs
fi


if [ -n "$luks_new_Disk_Recovery_Key_desired" -a -n "$luks_new_Disk_Recovery_Key_passphrase_desired" ]; then
    #Reencryption of disk, disk recovery key and Disk Recovery Key passphrase change is requested
    luks_reencrypt
    luks_change_passphrase
elif [ -n "$luks_new_Disk_Recovery_Key_desired" -a -z "$luks_new_Disk_Recovery_Key_passphrase_desired" ]; then
    #Reencryption of disk was requested but not passphrase change
    luks_reencrypt
elif [ -z "$luks_new_Disk_Recovery_Key_desired" -a -n "$luks_new_Disk_Recovery_Key_passphrase_desired" ]; then
    #Passphrase change is requested without disk reencryption
    luks_change_passphrase
fi

## reset TPM and set password
if [ "$CONFIG_TPM" = "y" ]; then
    echo -e "\nResetting TPM...\n"
    tpmr reset "$TPM_PASS" >/dev/null 2>/tmp/error
fi
if [ $? -ne 0 ]; then
    ERROR=$(tail -n 1 /tmp/error | fold -s)
    whiptail_error_die "Error resetting TPM:\n\n${ERROR}"
fi

# clear local keyring
rm /.gnupg/*.gpg 2>/dev/null
rm /.gnupg/*.kbx 2>/dev/null
gpg --list-keys >/dev/null 2>&1

#Generate key in memory and copy to smartcard
if [ "$GPG_GEN_KEY_IN_MEMORY" == "1" ]; then
    # Generate GPG master key
    generate_inmemory_RSA_master_and_subkeys
    #TODO seperate wiping and thumb drive functions with proper validation
    wipe_thumb_drive_and_copy_gpg_key_material
    #TODO seperate setting config
    set_user_config CONFIG_HAVE_GPG_KEY_BACKUP y
    gpg_key_factory_reset
    keytocard_subkeys_to_smartcard
else
    #Generate GPG key and subkeys on smartcard
    ## reset the GPG Key
    echo -e "\nResetting GPG Key...\n(this will take around 3 minutes...)\n"
    gpg_key_factory_reset
    generate_OEM_gpg_keys
fi

# Obtain GPG key ID
GPG_GEN_KEY=$(gpg --list-keys --with-colons | grep "^fpr" | cut -d: -f10 | head -n1)
#Where to export the public key
PUBKEY="/tmp/${GPG_GEN_KEY}.asc"

DEBUG "GPG_GEN_KEY: $GPG_GEN_KEY"
DEBUG "PUBKEY: $PUBKEY"

# export pubkey to file
if ! gpg --export --armor "$GPG_GEN_KEY" >"${PUBKEY}" 2>/tmp/error; then
    ERROR=$(tail -n 1 /tmp/error | fold -s)
    whiptail_error_die "GPG Key gpg export to file failed!\n\n$ERROR"
fi


#Applying custom GPG PINs if keys were not generated in memory
if [ "$GPG_GEN_KEY_IN_MEMORY" == "0" ]; then
    if [ "$USER_PIN" != "" -o "$ADMIN_PIN" != "" ]; then
        echo -e "\nChanging default GPG Admin PIN\n"
        gpg_key_change_pin "3" "$ADMIN_PIN_DEF" "$ADMIN_PIN"
        echo -e "\nChanging default GPG User PIN\n"
        gpg_key_change_pin "1" "$USER_PIN_DEF" "$USER_PIN"
    fi

    ## export pubkey to USB
    if [ $GPG_EXPORT -ne 0 ]; then
        echo -e "\nExporting generated key to USB...\n"
        # copy to USB
        if ! cp "${PUBKEY}" "/media/${GPG_GEN_KEY}.asc" 2>/tmp/error; then
            ERROR=$(tail -n 1 /tmp/error | fold -s)
            whiptail_error_die "Key export error: unable to copy ${GPG_GEN_KEY}.asc to /media:\n\n$ERROR"
        fi
        mount -o remount,ro /media 2>/dev/null
    fi
fi

## flash generated key to ROM
echo -e "\nReading current firmware...\n(this will take a minute or two)\n"
/bin/flash.sh -r /tmp/oem-setup.rom >/dev/null 2>/tmp/error
if [ ! -s /tmp/oem-setup.rom ]; then
    ERROR=$(tail -n 1 /tmp/error | fold -s)
    whiptail_error_die "Error reading current firmware:\n\n$ERROR"
fi

# ensure key imported locally
if ! cat "$PUBKEY" | gpg --import >/dev/null 2>/tmp/error; then
    ERROR=$(tail -n 1 /tmp/error | fold -s)
    whiptail_error_die "Error importing GPG key:\n\n$ERROR"
fi
# update /.gnupg/trustdb.gpg to ultimately trust all user provided public keys
if ! gpg --list-keys --fingerprint --with-colons 2>/dev/null |
    sed -E -n -e 's/^fpr:::::::::([0-9A-F]+):$/\1:6:/p' |
    gpg --import-ownertrust >/dev/null 2>/tmp/error; then
    ERROR=$(tail -n 1 /tmp/error | fold -s)
    whiptail_error_die "Error importing GPG ownertrust:\n\n$ERROR"
fi
if ! gpg --update-trust >/dev/null 2>/tmp/error; then
    ERROR=$(tail -n 1 /tmp/error | fold -s)
    whiptail_error_die "Error updating GPG ownertrust:\n\n$ERROR"
fi

# clear any existing heads/gpg files from current firmware
for i in $(cbfs.sh -o /tmp/oem-setup.rom -l | grep -e "heads/"); do
    cbfs.sh -o /tmp/oem-setup.rom -d "$i"
done
# add heads/gpg files to current firmware

if [ -e /.gnupg/pubring.kbx ]; then
    cbfs.sh -o /tmp/oem-setup.rom -a "heads/initrd/.gnupg/pubring.kbx" -f /.gnupg/pubring.kbx
    if [ -e /.gnupg/pubring.gpg ]; then
        rm /.gnupg/pubring.gpg
    fi
elif [ -e /.gnupg/pubring.gpg ]; then
    cbfs.sh -o /tmp/oem-setup.rom -a "heads/initrd/.gnupg/pubring.gpg" -f /.gnupg/pubring.gpg
fi
if [ -e /.gnupg/trustdb.gpg ]; then
    cbfs.sh -o /tmp/oem-setup.rom -a "heads/initrd/.gnupg/trustdb.gpg" -f /.gnupg/trustdb.gpg
fi

# persist user config changes (boot device)
if [ -e /etc/config.user ]; then
    cbfs.sh -o /tmp/oem-setup.rom -a "heads/initrd/etc/config.user" -f /etc/config.user
fi

# flash updated firmware image
echo -e "\nAdding generated key to current firmware and re-flashing...\n"
if ! /bin/flash.sh /tmp/oem-setup.rom 2>/tmp/error; then
    ERROR=$(tail -n 1 /tmp/error | fold -s)
    whiptail_error_die "Error flashing updated firmware image:\n\n$ERROR"
fi

## sign files in /boot and generate checksums
if [[ "$SKIP_BOOT" == "n" ]]; then
    echo -e "\nSigning boot files and generating checksums...\n"
    generate_checksums
fi

# Prepare whiptail output of provisioned secrets
if [ -z "$luks_new_Disk_Recovery_Key_passphrase" -o -z "$luks_new_Disk_Recovery_Key_passphrase_desired" ]; then
    luks_passphrase_changed=""
else
    luks_passphrase_changed="LUKS Disk Recovery Key passphrase:\n
     $luks_new_Disk_Recovery_Key_passphrase"
fi

if [ "$CONFIG_TPM" = "y" ]; then
    tpm_owner_password_changed="
    TPM Owner Password: $TPM_PASS\n"
else
    tpm_owner_password_changed=""
fi

## Show to user current provisioned secrets prior of rebooting
whiptail --msgbox "
    $luks_passphrase_changed
    $tpm_owner_password_changed
    GPG Admin PIN: $ADMIN_PIN\n
    GPG User PIN: $USER_PIN\n\n" \
    $HEIGHT $WIDTH --title "Provisioned secrets"

## all done -- reboot
whiptail --msgbox "
    OEM Factory Reset / Re-Ownership has completed successfully\n\n
    After rebooting, you will need to generate new TOTP/HOTP secrets\n
    when prompted in order to complete the setup process.\n\n
    Press Enter to reboot.\n" \
    $HEIGHT $WIDTH --title "OEM Factory Reset / Re-Ownership Complete"

# Clean LUKS secrets
luks_secrets_cleanup
unset luks_passphrase_changed
unset tpm_owner_password_changed

reboot