#!/bin/bash -ex
# vim: set tabstop=8 shiftwidth=4 softtabstop=4 expandtab smarttab colorcolumn=80:
#
# Copyright (c) 2019 Red Hat, Inc.
# Author: Sergio Correia <scorreia@redhat.com>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

error() {
    echo "${1}" >&2
    exit 1
}

skip_test() {
    echo "${1}" >&2
    exit 77
}

# We require cryptsetup >= 2.0.4 to fully support LUKSv2.
# Support is determined at build time.
luks2_supported() {
    return @OLD_CRYPTSETUP@
}

# Creates a tang adv to be used in the test.
create_tang_adv() {
    local adv="${1}"
    local SIG="${TMP}/sig.jwk"
    jose jwk gen -i '{"alg":"ES512"}' > "${SIG}"

    local EXC="${TMP}/exc.jwk"
    jose jwk gen -i '{"alg":"ECMR"}' > "${EXC}"

    local TEMPLATE='{"protected":{"cty":"jwk-set+json"}}'
    jose jwk pub -s -i "${SIG}" -i "${EXC}" \
        | jose jws sig -I- -s "${TEMPLATE}" -k "${SIG}" -o "${adv}"
}

# Creates a new LUKS1 or LUKS2 device to be used.
new_device() {
    local LUKS="${1}"
    local DEV="${2}"
    local PASS="${3}"

    # Some builders fail if the cryptsetup steps are not ran as root, so let's
    # skip the test now if not running as root.
    if [ "$(id -u)" != 0 ]; then
        skip_test "WARNING: You must be root to run this test; test skipped."
    fi

    # Using a default password, if none has been provided.
    if [ -z "${PASS}" ]; then
        PASS="${DEFAULT_PASS}"
    fi

    local DEV_CACHED="${TMP}/${LUKS}.cached"

    # Let's reuse an existing device, if there is one.
    if [ -f "${DEV_CACHED}" ]; then
        echo "Reusing cached ${LUKS} device..."
        cp -f "${DEV_CACHED}" "${DEV}"
        return 0
    fi

    fallocate -l64M "${DEV}"
    cryptsetup luksFormat --type "${LUKS}" --pbkdf pbkdf2 \
        --pbkdf-force-iterations 1000 --batch-mode \
        --force-password "${DEV}" <<< "${PASS}"
    # Caching the just-formatted device for possible reuse.
    cp -f "${DEV}" "${DEV_CACHED}"
}

# Creates a new LUKS1 or LUKS2 device to be used, using a keyfile.
new_device_keyfile() {
    local LUKS="${1}"
    local DEV="${2}"
    local KEYFILE="${3}"

    # Some builders fail if the cryptsetup steps are not ran as root, so let's
    # skip the test now if not running as root.
    if [ "$(id -u)" != 0 ]; then
        skip_test "WARNING: You must be root to run this test; test skipped."
    fi

    if [[ -z "${KEYFILE}" ]] || [[ ! -f "${KEYFILE}" ]]; then
        error "Invalid keyfile (${KEYFILE})."
    fi

    fallocate -l64M "${DEV}"
    cryptsetup luksFormat --type "${LUKS}" --pbkdf pbkdf2 \
        --pbkdf-force-iterations 1000 --batch-mode \
        "${DEV}" "${KEYFILE}"
}

pin_cfg_equal() {
    # Let's remove the single quotes from the pin configuration.
    local cfg1="${1//\'/}"
    local cfg2="${2//\'/}"

    # Now we sort and present them in compact form.
    local sorted_cfg1 sorted_cfg2
    sorted_cfg1="$(jq --compact-output --sort-keys . < <(echo -n "${cfg1}"))"
    sorted_cfg2="$(jq --compact-output --sort-keys . < <(echo -n "${cfg2}"))"

    # And we finally compare.
    if [ "${sorted_cfg1}" = "${sorted_cfg2}" ]; then
        return 0
    fi
    return 1
}

compare_luks_header() {
    DEV1="${1}"
    DEV2="${2}"
    TMP="${3}"

    cryptsetup luksHeaderBackup "${DEV1}" \
               --header-backup-file "${TMP}"/check-header1
    cryptsetup luksHeaderBackup "${DEV2}" \
               --header-backup-file "${TMP}"/check-header2

    local cs1 cs2
    cs1=$(cksum "${TMP}"/check-header1 | cut -d' ' -f 1)
    cs2=$(cksum "${TMP}"/check-header2 | cut -d' ' -f 1)
    rm -f "${TMP}"/check-header{1,2}

    if [ "${cs1}" == "${cs2}" ]; then
        return 0
    fi
    return 1
}

used_luks1_metadata_slots() {
    DEV="${1}"
    if ! luksmeta test -d "${DEV}"; then
        echo ""
        return 0
    fi

    local clevis_uuid="cb6e8904-81ff-40da-a84a-07ab9ab5715e"
    luksmeta show -d "${DEV}" \
        | sed -rn "s|^([0-9]+)\s+active\s+${clevis_uuid}$|\1|p" \
        | tr '\n' ' ' | sed 's/ $//'
}

used_luks2_metadata_slots() {
    DEV="${1}"
    cryptsetup luksDump "${DEV}" \
        | grep -E -A1 "^\s+[0-9]+:\s+clevis$" \
        | sed -rn 's|^\s+Keyslot:\s+([0-9]+)$|\1|p' | sort -n \
        | tr '\n' ' ' | sed 's/ $//'
}

used_luks2_metadata_tokens() {
    DEV="${1}"
    cryptsetup luksDump "${DEV}" \
        | grep -E -B1 "^\s+Keyslot:\s+[0-9]+$" \
        | sed -rn 's|^\s+([0-9]+): clevis|\1|p' \
        | tr '\n' ' ' | sed 's/ $//'
}

compare_luks1_metadata() {
    DEV1="${1}"
    DEV2="${2}"

    # If both are non-initialized, metadata is the same.
    ! luksmeta test -d "${DEV1}" && ! luksmeta test -d "${DEV2}" && return 0
    # Otherwise, metadata differ.
    ! luksmeta test -d "${DEV1}" && return 1
    ! luksmeta test -d "${DEV2}" && return 1

    local slt1 slt2
    slt1=$(used_luks1_metadata_slots "${DEV1}")
    slt2=$(used_luks1_metadata_slots "${DEV2}")

    if [ "${slt1}" != "${slt2}" ]; then
        echo "used slots did not match ($slt1) ($slt2)" >&2
        return 1
    fi

    local slt md1 md2
    for slt in ${slt1}; do
        md1="$(luksmeta load -d "${DEV}" -s "${slt}")"
        md2="$(luksmeta load -d "${DEV2}" -s "${slt}")"
        if [ "${md1}" != "${md2}" ]; then
            echo "metadata in slot ${slt} did not match" >&2
            return 1
        fi
    done
    return 0
}

compare_luks2_metadata() {
    DEV1="${1}"
    DEV2="${2}"

    local slt1 slt2
    slt1=$(used_luks2_metadata_slots "${DEV1}")
    slt2=$(used_luks2_metadata_slots "${DEV2}")

    if [ "${slt1}" != "${slt2}" ]; then
        echo "used slots did not match ($slt1) ($slt2)" >&2
        return 1
    fi

    local tkn1 tkn2
    tkn1=$(used_luks2_metadata_tokens "${DEV1}")
    tkn2=$(used_luks2_metadata_tokens "${DEV2}")

    if [ "${tkn1}" != "${tkn2}" ]; then
        echo "used tokens did not match ($tkn1) ($tkn2)" >&2
        return 1
    fi

    local tkn md1 md2
    for tkn in ${tkn1}; do
        md1="$(cryptsetup token export --token-id "${tkn}" "${DEV1}")"
        md2="$(cryptsetup token export --token-id "${tkn}" "${DEV2}")"
        if [ "${md1}" != "${md2}" ]; then
            echo "metadata in token ${tkn} did not match" >&2
            return 1
        fi
    done
    return 0
}


# Get a random port to be used with a test tang server.
get_random_port() {
    shuf -i 1024-65535 -n 1
}

# Removes tang rotated keys from the test server.
tang_remove_rotated_keys() {
    local basedir="${1}"

    if [ -z "${basedir}" ]; then
        echo "Please pass a valid base directory for tang"
        return 1
    fi

    [ -z "${TANGD_UPDATE}" ] && skip_test "WARNING: TANGD_UPDATE is not defined."

    local db="${basedir}/db"
    local cache="${basedir}/cache"
    mkdir -p "${db}"
    mkdir -p "${cache}"

    pushd "${db}"
        find . -name ".*.jwk" -exec rm -f {} \;
    popd

    "${TANGD_UPDATE}" "${db}" "${cache}"
    return 0
}

# Creates new keys for the test tang server.
tang_new_keys() {
    local basedir="${1}"
    local rotate="${2}"

    if [ -z "${basedir}" ]; then
        echo "Please pass a valid base directory for tang"
        return 1
    fi

    [ -z "${TANGD_KEYGEN}" ] && skip_test "WARNING: TANGD_KEYGEN is not defined."
    [ -z "${TANGD_UPDATE}" ] && skip_test "WARNING: TANGD_UPDATE is not defined."

    local db="${basedir}/db"
    local cache="${basedir}/cache"
    mkdir -p "${db}"

    if [ -n "${rotate}" ]; then
        pushd "${db}"
            local k
            k=$(find . -name "*.jwk" | wc -l)
            if [ "${k}" -gt 0 ]; then
                for k in *.jwk; do
                    mv -f -- "${k}" ".${k}"
                done
            fi
        popd
    fi

    "${TANGD_KEYGEN}" "${db}"
    "${TANGD_UPDATE}" "${db}" "${cache}"

    return 0
}

# Start a test tang server.
tang_run() {
    local basedir="${1}"
    local port="${2}"

    if [ -z "${basedir}" ]; then
        echo "Please pass a valid base directory for tang" >&2
        return 1
    fi

    if [ -z "${port}" ]; then
        echo "Please pass a valid port for tang" >&2
        return 1
    fi

    if ! tang_new_keys "${basedir}"; then
        echo "Error creating new keys for tang server" >&2
        return 1
    fi

    local KEYS="${basedir}/cache"
    local inetd='--inetd'
    [ "${SD_ACTIVATE##*/}" = "systemd-activate" ] && inetd=

    local pid pidfile
    pidfile="${basedir}/tang.pid"

    "${SD_ACTIVATE}" ${inetd} -l "${TANG_HOST}":"${port}" \
            -a "${TANGD}" "${KEYS}" &
    pid=$!
    echo "${pid}" > "${pidfile}"
}

# Stop tang server.
tang_stop() {
    local basedir="${1}"
    local pidfile="${basedir}/tang.pid"
    [ -f "${pidfile}" ] || return 0

    local pid
    pid=$(<"${pidfile}")
    kill "${pid}"
}

# Wait for the tang server to be operational.
tang_wait_until_ready() {
   local port="${1}"
   while ! curl --output /dev/null --silent --fail \
                http://"${TANG_HOST}":"${port}"/adv; do
       sleep 0.1
       echo -n . >&2
   done
}

# Get tang advertisement.
tang_get_adv() {
    local port="${1}"
    local adv="${2}"

    curl -o "${adv}" http://"${TANG_HOST}":"${port}"/adv
}

export TANG_HOST=127.0.0.1
export DEFAULT_PASS='just-some-test-password-here'