#!/bin/sh
# SPDX-License-Identifier: Apache-2.0
# (c) 2024, Konstantin Demin

set -ef

# Prevent core dumps
set +e
ulimit -Sc 0
ulimit -Hc 0
set -e

# not needed anyway
unset LD_PRELOAD

binary=$(command -v vault) ; : "${binary:?}"
binary=$(readlink -e "${binary}") ; : "${binary:?}"

have_capability() {
    # local cap=$1
    setpriv -d | awk -F: '/^Capability bounding set:/{print $2}' | grep -Eiq "(^\s*|,)$1(,|\$)"
}

have_ipc_lock=1
have_capability ipc_lock || have_ipc_lock=0

# ref: https://pkg.go.dev/strconv#ParseBool
gobool_to_int() {
    # local value=$1
    # local default=$2
    case "$1" in
    1 | t | T | TRUE  | true  | True )  echo 1 ;;
    0 | f | F | FALSE | false | False ) echo 0 ;;
    * ) echo "${2:-error}" ;;
    esac
}

int_to_gobool() {
    # local int=$1
    case "$1" in
    0 ) echo false ;;
    1 ) echo true ;;
    esac
}

# ref: https://developer.hashicorp.com/vault/docs/configuration#disable_mlock
with_mlock=$(gobool_to_int "${VAULT_DISABLE_MLOCK:-0}" 1)
with_mlock=$((1 - with_mlock))

# VAULT_CONFIG_DIR isn't exposed as a volume but you can compose additional
# config files in there if you use this image as a base, or use
# VAULT_LOCAL_CONFIG below.
VAULT_CONFIG_DIR=${VAULT_CONFIG_DIR:-/vault/config}

case "$1" in
vault )
    # no adjustments are required - running Vault with directly specified command and options
    :
;;
-* )
    # running with options
    set -- vault "$@"
;;
server )
    shift

    dev_mode=0
    have_dev_listen=0
    for i ; do
        case "$i" in
        -dev | -dev-tls )
            dev_mode=1
        ;;
        -dev-listen-address )
            have_dev_listen=1
        ;;
        esac
    done ; unset i
    # adjust environment for dev mode
    if [ "${dev_mode}" = 1 ] && [ "${have_dev_listen}" = 0 ] ; then
        export VAULT_DEV_LISTEN_ADDRESS="${VAULT_DEV_LISTEN_ADDRESS:-"0.0.0.0:8200"}"
    fi
    # not needed anymore
    unset dev_mode have_dev_listen

    set -- vault server \
      -config="${VAULT_CONFIG_DIR}" \
      "$@"
;;
version )
    set -- vault "$@"
;;
* )
    if vault --help "$1" 2>&1 | grep -Fq "vault $1" ; then
        # We can't use the return code to check for the existence of a subcommand, so
        # we have to use grep to look for a pattern in the help output.
        set -- vault "$@"
    fi
;;
esac

if [ "$1" != 'vault' ] ; then
    unset SKIP_PERMCHECK SKIP_IPC_LOCK SKIP_VAULT_PRECONF SKIP_CHOWN SKIP_SETCAP
    SKIP_PERMCHECK=1 SKIP_IPC_LOCK=1 SKIP_VAULT_PRECONF=1 SKIP_CHOWN=1 SKIP_SETCAP=1
fi

if [ "${SKIP_PERMCHECK:-0}" != 1 ] ; then
    # Due to OpenShift environment compatibility, we have to allow group write
    # access to the Vault configuration. This requires us to disable the stricter
    # file permissions checks introduced in Vault v1.11.0.
    # ref: https://developer.hashicorp.com/vault/docs/configuration
    with_permcheck=0

    x=none

    # Vault 1.11 and older
    if [ -n "${VAULT_DISABLE_FILE_PERMISSIONS_CHECK}" ] ; then
        x=$(gobool_to_int "${VAULT_DISABLE_FILE_PERMISSIONS_CHECK}")
        case "$x" in
        0 | 1 ) with_permcheck=$((1 - x)) ;;
        esac
    fi

    # Vault 1.12 and newer
    if [ -n "${VAULT_ENABLE_FILE_PERMISSIONS_CHECK}" ] ; then
        x=$(gobool_to_int "${VAULT_ENABLE_FILE_PERMISSIONS_CHECK}")
        case "$x" in
        0 | 1 ) with_permcheck=$x ;;
        esac
    fi

    unset x

    # adjust variables
    set -a
    VAULT_ENABLE_FILE_PERMISSIONS_CHECK=$(int_to_gobool "${with_permcheck}")
    VAULT_DISABLE_FILE_PERMISSIONS_CHECK=$(int_to_gobool $((1 - with_permcheck)) )
    set +a
    unset with_permcheck
fi
unset SKIP_PERMCHECK

if [ "${SKIP_IPC_LOCK:-0}" != 1 ] ; then
    if [ "${have_ipc_lock}" = 1 ] ; then
        set +e

        echo "Limits before:"
        # sed -En '1p;/[Ll]ocked/p' < /proc/$$/limits
        awk 'NR==1{print} /[Ll]ocked/{print}' /proc/$$/limits

        ulimit -Hl "${MEMLOCK_LIMIT:-unlimited}"
        x=$(ulimit -Hl)
        ulimit -Sl "$x"
        unset x

        echo "Limits after:"
        # sed -En '1p;/[Ll]ocked/p' < /proc/$$/limits
        awk 'NR==1{print} /[Ll]ocked/{print}' /proc/$$/limits

        set -e
    fi >&2

    if [ "${with_mlock}" = 1 ] && [ "${have_ipc_lock}" = 0 ] ; then
        echo
        echo '!!!'
        echo
        echo "missing CAP_IPC_LOCK privilege: please run container with \`--cap-add IPC_LOCK'"
        echo 'ref: https://developer.hashicorp.com/vault/docs/configuration#disable_mlock'
        echo
        echo '!!!'
        echo
    fi >&2
fi
unset SKIP_IPC_LOCK

if [ "${SKIP_VAULT_PRECONF:-0}" != 1 ] ; then
    # You can also set the VAULT_LOCAL_CONFIG environment variable to pass some
    # Vault configuration JSON without having to bind any volumes.
    VAULT_LOCAL_CONFIG_FILE=${VAULT_LOCAL_CONFIG_FILE:-"${VAULT_CONFIG_DIR}/local.json"}
    while [ -n "${VAULT_LOCAL_CONFIG}" ] ; do
        touch "${VAULT_LOCAL_CONFIG_FILE}" || break
        printf '%s' "${VAULT_LOCAL_CONFIG}" > "${VAULT_LOCAL_CONFIG_FILE}" || break
        break
    done
    unset VAULT_LOCAL_CONFIG VAULT_LOCAL_CONFIG_FILE

    # Allow setting VAULT_REDIRECT_ADDR and VAULT_CLUSTER_ADDR using an interface
    # name instead of an IP address. The interface name is specified using
    # VAULT_REDIRECT_INTERFACE and VAULT_CLUSTER_INTERFACE environment variables. If
    # VAULT_*_ADDR is also set, the resulting URI will combine the protocol and port
    # number with the IP of the named interface.

    have_iproute2=1
    command -v ip >/dev/null 2>&1 || have_iproute2=0
    err_iproute2_missing() {
        printf '%s\n' "$1: iproute2 (/usr/sbin/ip) is missing" >&2
    }

    err_iface_missing() {
        printf '%s\n' "$1: interface error" >&2
    }
    err_ipv4_addr_missing() {
        printf '%s\n' "$1: no IPv4 addresses are present on interface" >&2
    }

    iface_exist() {
        # local if_name=$1
        ip link show dev "$1" >/dev/null
    }
    get_iface_ipv4_addr () {
        # local if_name=$1
        # local uri_template=$2
        ip address show dev "$1" \
        | awk -v "uri=$2" \
        '/^\s*inet\s/ {
            ip=gensub(/(.+)\/.+/, "\\1", "g", $2)
            print gensub(/^(.+:\/\/).+(:.+)$/, "\\1" ip "\\2", "g", uri)
            exit
        }'
    }

    while [ -n "${VAULT_REDIRECT_INTERFACE}" ] ; do
        new_vault_redirect_addr=${VAULT_REDIRECT_ADDR:-"http://0.0.0.0:8200"}
        errmsg_vault_redirect_interface="unable to adjust VAULT_REDIRECT_ADDR='${new_vault_redirect_addr}' with VAULT_REDIRECT_INTERFACE='${VAULT_REDIRECT_INTERFACE}'"

        if [ "${have_iproute2}" = 0 ] ; then
            err_iproute2_missing "${errmsg_vault_redirect_interface}"
            break
        fi
        if ! iface_exist "${VAULT_REDIRECT_INTERFACE}" ; then
            err_iface_missing "${errmsg_vault_redirect_interface}"
            break
        fi

        set +e
        new_vault_redirect_addr=$(get_iface_ipv4_addr "${VAULT_REDIRECT_INTERFACE}" "${new_vault_redirect_addr}")
        set -e
        if [ -z "${new_vault_redirect_addr}" ] ; then
            err_ipv4_addr_missing "${errmsg_vault_redirect_interface}"
            break
        fi

        if [ -n "${VAULT_REDIRECT_ADDR}" ] && [ "${VAULT_REDIRECT_ADDR}" != "${new_vault_redirect_addr}" ]; then
            echo "changing VAULT_REDIRECT_ADDR: ${VAULT_REDIRECT_ADDR} -> ${new_vault_redirect_addr}" >&2
        fi
        export VAULT_REDIRECT_ADDR="${new_vault_redirect_addr}"
        echo "using interface ${VAULT_REDIRECT_INTERFACE} for VAULT_REDIRECT_ADDR: ${VAULT_REDIRECT_ADDR}" >&2
        break
    done
    unset VAULT_REDIRECT_INTERFACE new_vault_redirect_addr errmsg_vault_redirect_interface

    while [ -n "${VAULT_CLUSTER_INTERFACE}" ] ; do
        new_vault_cluster_addr=${VAULT_CLUSTER_ADDR:-"https://0.0.0.0:8201"}
        errmsg_vault_cluster_interface="unable to adjust VAULT_CLUSTER_ADDR='${new_vault_cluster_addr}' with VAULT_CLUSTER_INTERFACE='${VAULT_CLUSTER_INTERFACE}'"

        if [ "${have_iproute2}" = 0 ] ; then
            err_iproute2_missing "${errmsg_vault_cluster_interface}"
            break
        fi
        if ! iface_exist "${VAULT_CLUSTER_INTERFACE}" ; then
            err_iface_missing "${errmsg_vault_cluster_interface}"
            break
        fi

        set +e
        new_vault_cluster_addr=$(get_iface_ipv4_addr "${VAULT_CLUSTER_INTERFACE}" "${new_vault_cluster_addr}")
        set -e
        if [ -z "${new_vault_cluster_addr}" ] ; then
            err_ipv4_addr_missing "${errmsg_vault_cluster_interface}"
            break
        fi

        if [ -n "${VAULT_CLUSTER_ADDR}" ] && [ "${VAULT_CLUSTER_ADDR}" != "${new_vault_cluster_addr}" ] ; then
            echo "changing VAULT_CLUSTER_ADDR: ${VAULT_CLUSTER_ADDR} -> ${new_vault_cluster_addr}" >&2
        fi
        export VAULT_CLUSTER_ADDR="${new_vault_cluster_addr}"
        echo "using ${VAULT_CLUSTER_INTERFACE} for VAULT_CLUSTER_ADDR: ${VAULT_CLUSTER_ADDR}"
        break
    done
    unset VAULT_CLUSTER_INTERFACE new_vault_cluster_addr errmsg_vault_cluster_interface
fi
unset SKIP_VAULT_PRECONF

while [ "${SKIP_CHOWN:-0}" != 1 ] ; do
    vault_uid=$(id -u vault) || break

    fix_ownership() {
        x=0
        for i ; do
            [ -n "$i" ] || continue

            if ! [ -d "$i" ] ; then
                # NB: running through `env' to avoid shell glitch
                env printf 'not a directory: %q\n' "$i" >&2
                continue
            fi

            # NB: running through `env' to avoid shell glitch
            x=$(env stat -Lc '%u' "$i")
            if [ "$x" = "${vault_uid}" ] ; then
                # nothing to fix (probably)
                continue
            fi

            if ! chown -R vault:vault "$i" ; then
                # NB: running through `env' to avoid shell glitch
                env printf 'Could not chown %q (may not have appropriate permissions)\n' "$i" >&2
            fi
        done
        unset x i
    }

    find_fast() {
        find "$@" -printf . -quit | grep -Fq .
    }

    check_ownership() {
        for i ; do
            [ -n "$i" ] || continue

            if ! [ -d "$i" ] ; then
                # NB: running through `env' to avoid shell glitch
                env printf 'not a directory: %q\n' "$i" >&2
                continue
            fi

            find_fast "$i/" ! -uid "${vault_uid}" || continue

            echo "files not owned by Vault:" >&2
            set +e
            find "$i/" ! -uid "${vault_uid}" -ls
            set -e
        done
        unset i
    }

    fix_ownership   /vault/config /vault/logs /vault/file
    check_ownership /vault/config /vault/logs /vault/file

    break
done
unset SKIP_CHOWN

if [ "${SKIP_SETCAP:-0}" != 1 ] ; then
    have_libcap2=1
    command -v setcap >/dev/null 2>&1 || have_libcap2=0
    err_libcap2_missing() {
        printf '%s\n' "$1: libcap2-bin (/usr/sbin/setcap) is missing" >&2
    }

    drop_ipc_lock=0
    # try running Vault with CAP_IPC_LOCK
    while [ "${with_mlock}" = 1 ] ; do
        errmsg_vault_mlock="unable to run Vault with CAP_IPC_LOCK"

        if [ "${have_libcap2}" = 0 ] ; then
            err_libcap2_missing "${errmsg_vault_mlock}"
            break
        fi

        if ! setcap cap_ipc_lock=+ep "${binary}" ; then
            echo "${errmsg_vault_mlock}: setcap failed (read-only filesystem?)"
            break
        fi

        # In the case vault has been started in a container without IPC_LOCK privileges
        if ! "${binary}" -version >/dev/null 2>&1 ; then
            echo "${errmsg_vault_mlock}"
            drop_ipc_lock=1
            break
        fi

        break
    done
    unset errmsg_vault_mlock

    # not needed anymore
    unset have_libcap2

    if [ "${drop_ipc_lock}" = 1 ] ; then
        # ignore any error
        setcap cap_ipc_lock=-ep "${binary}" || :
    fi
    unset drop_ipc_lock
fi
unset SKIP_SETCAP

# not needed anymore
unset have_ipc_lock have_iproute2 with_mlock

# In case of Docker, where swap may be enabled, we
# still require mlocking to be available. So this script
# was executed as root to make this happen, however,
# we're now rerunning the entrypoint script as the Vault
# user but no longer need to run setup code for setcap
# or chowning directories (previously done on the first run).
if [ "$(id -u)" = '0' ] ; then
    export SKIP_PERMCHECK=1 SKIP_IPC_LOCK=1 SKIP_VAULT_PRECONF=1 SKIP_CHOWN=1 SKIP_SETCAP=1
    exec \
      setpriv --reuid=vault --regid=vault --init-groups \
        env USER=vault LOGNAME=vault HOME=/home/vault SHELL=/bin/sh \
          "$0" "$@"
else
    exec "$@"
fi