From 2acf8677fa85ee2d3d53de401e490e530a1049cc Mon Sep 17 00:00:00 2001 From: aszlig Date: Mon, 11 Apr 2016 11:52:02 +0200 Subject: [PATCH] nixos/taskserver: Rewrite helper-tool in Python In the comments of the pull request @nbp wrote: "Why is it implemented in 3 different languages: Nix, Bash and C?" And he's right, it doesn't make sense, because we were using C as a runuser replacement and used Nix to generate the shellscript boilerplates. Writing this in Python gets rid of all of this and we also don't need the boilerplate as well, because we're using Click to handle all the command line stuff. Note that this currently is a 1:1 implementation of what we had before. Signed-off-by: aszlig --- .../services/misc/taskserver/default.nix | 26 +- .../services/misc/taskserver/helper-tool.nix | 324 ------------------ .../services/misc/taskserver/helper-tool.py | 276 +++++++++++++++ 3 files changed, 299 insertions(+), 327 deletions(-) delete mode 100644 nixos/modules/services/misc/taskserver/helper-tool.nix create mode 100644 nixos/modules/services/misc/taskserver/helper-tool.py diff --git a/nixos/modules/services/misc/taskserver/default.nix b/nixos/modules/services/misc/taskserver/default.nix index 62e35803117..86eabb9bcfc 100644 --- a/nixos/modules/services/misc/taskserver/default.nix +++ b/nixos/modules/services/misc/taskserver/default.nix @@ -80,9 +80,29 @@ let mkShellStr = val: "'${replaceStrings ["'"] ["'\\''"] val}'"; - nixos-taskserver = import ./helper-tool.nix { - inherit pkgs lib mkShellStr taskd; - config = cfg; + nixos-taskserver = pkgs.buildPythonPackage { + name = "nixos-taskserver"; + namePrefix = ""; + + src = pkgs.runCommand "nixos-taskserver-src" {} '' + mkdir -p "$out" + cat "${pkgs.substituteAll { + src = ./helper-tool.py; + certtool = "${pkgs.gnutls}/bin/certtool"; + inherit taskd; + inherit (cfg) dataDir user group; + inherit (cfg.server) fqdn; + }}" > "$out/main.py" + cat > "$out/setup.py" < "$tmpdir/template" <<-\ \ EOF - organization = $organisation - cn = ${config.server.fqdn} - tls_www_client - encryption_key - signing_key - EOF - - ${pkgs.gnutls}/bin/certtool -c \ - --load-privkey "$tmpdir/key" \ - --load-ca-privkey "${config.dataDir}/keys/ca.key" \ - --load-ca-certificate "${config.dataDir}/keys/ca.cert" \ - --template "$tmpdir/template" \ - --outfile "$tmpdir/cert" - - mkdir -m 0700 -p "${config.dataDir}/keys/user/$organisation/$user" - chown root:root "${config.dataDir}/keys/user/$organisation/$user" - cat "$tmpdir/key" \ - > "${config.dataDir}/keys/user/$organisation/$user/private.key" - cat "$tmpdir/cert" \ - > "${config.dataDir}/keys/user/$organisation/$user/public.cert" - - rm -rf "$tmpdir" - trap - EXIT - else - echo "Unable to create temporary directory for client" \ - "certificate creation." >&2 - exit 1 - fi - ''; - - mkSubCommand = name: { args, description, script }: let - mkArg = pos: arg: "local ${arg}=\"\$${toString pos}\""; - mkDesc = line: "echo ${mkShellStr " ${line}"} >&2"; - usagePosArgs = lib.concatMapStringsSep " " (a: "<${a}>") args; - in '' - subcmd_${mkShellName name}() { - ${lib.concatImapStringsSep "\n " mkArg args} - ${script} - } - - usage_${mkShellName name}() { - echo " ${commandName} ${name} ${usagePosArgs}" >&2 - ${lib.concatMapStringsSep "\n " mkDesc description} - } - ''; - - mkCStr = val: "\"${lib.escape ["\\" "\""] val}\""; - - taskdUser = let - runUser = pkgs.writeText "runuser.c" '' - #include - #include - #include - #include - #include - #include - #include - - int main(int argc, char **argv) { - struct passwd *userinfo; - struct group *groupinfo; - errno = 0; - if ((userinfo = getpwnam(${mkCStr config.user})) == NULL) { - if (errno == 0) - fputs(${mkCStr "User name `${config.user}' not found."}, stderr); - else - perror("getpwnam"); - return EXIT_FAILURE; - } - errno = 0; - if ((groupinfo = getgrnam(${mkCStr config.group})) == NULL) { - if (errno == 0) - fputs(${mkCStr "Group name `${config.group}' not found."}, stderr); - else - perror("getgrnam"); - return EXIT_FAILURE; - } - if (setgid(groupinfo->gr_gid) == -1) { - perror("setgid"); - return EXIT_FAILURE; - } - if (setuid(userinfo->pw_uid) == -1) { - perror("setgid"); - return EXIT_FAILURE; - } - argv[0] = "taskd"; - if (execv(${mkCStr taskd}, argv) == -1) { - perror("execv"); - return EXIT_FAILURE; - } - /* never reached */ - return EXIT_SUCCESS; - } - ''; - in pkgs.runCommand "taskd-user" {} '' - cc -Wall -std=c11 "${runUser}" -o "$out" - ''; - - subcommands = { - list-users = { - args = [ "organisation" ]; - - description = [ - "List all users belonging to the specified organisation." - ]; - - script = '' - legend "The following users exist for $organisation:" - ${pkgs.findutils}/bin/find \ - "${config.dataDir}/orgs/$organisation/users" \ - -mindepth 2 -maxdepth 2 -name config \ - -exec ${pkgs.gnused}/bin/sed -ne 's/^user *= *//p' {} + - ''; - }; - - list-orgs = { - args = []; - - description = [ - "List available organisations" - ]; - - script = '' - legend "The following organisations exist:" - ${pkgs.findutils}/bin/find \ - "${config.dataDir}/orgs" -mindepth 1 -maxdepth 1 \ - -type d - ''; - }; - - get-uuid = { - args = [ "organisation" "user" ]; - - description = [ - "Get the UUID of the specified user belonging to the specified" - "organisation." - ]; - - script = '' - for uuid in "${config.dataDir}/orgs/$organisation/users"/*; do - usr="$(${pkgs.gnused}/bin/sed -ne 's/^user *= *//p' "$uuid/config")" - if [ "$usr" = "$user" ]; then - legend "User $user has the following UUID:" - echo "$(${pkgs.coreutils}/bin/basename "$uuid")" - exit 0 - fi - done - echo "No UUID found for user $user." >&2 - exit 1 - ''; - }; - - export-user = { - args = [ "organisation" "user" ]; - - description = [ - "Export user of the specified organisation as a series of shell" - "commands that can be used on the client side to easily import" - "the certificates." - "" - "Note that the private key will be exported as well, so use this" - "with care!" - ]; - - script = '' - if ! subcmd_quiet list-users "$organisation" | grep -qxF "$user"; then - exists "User $user doesn't exist in organisation $organisation." - fi - - uuid="$(subcmd_quiet get-uuid "$organisation" "$user")" || exit 1 - - cat < "\$taskdatadir/keys/public.cert" < "\$taskdatadir/keys/private.key" < "\$taskdatadir/keys/ca.cert" <&2 - echo >&2 - usage_${mkShellName name} - exit 1 - fi - subcmd "${name}" ${cmdArgs};; - ''; - -in pkgs.writeScriptBin commandName '' - #!${pkgs.stdenv.shell} - export TASKDDATA=${mkShellStr config.dataDir} - - quiet=0 - # Deliberately undocumented, because we don't want people to use this as - # it's only used in and specific to the preStart script of the Taskserver - # service. - if [ "$1" = "--service-helper" ]; then - quiet=1 - exists() { - exit 0 - } - shift - else - exists() { - echo "$@" >&2 - exit 1 - } - fi - - legend() { - if [ $quiet -eq 0 ]; then - echo "$@" >&2 - fi - } - - subcmd() { - local cmdname="''${1//-/_}" - shift - "subcmd_$cmdname" "$@" - } - - subcmd_quiet() { - local prev_quiet=$quiet - quiet=1 - subcmd "$@" - local ret=$? - quiet=$prev_quiet - return $ret - } - - ${lib.concatStrings (lib.mapAttrsToList mkSubCommand subcommands)} - - case "$1" in - ${lib.concatStrings (lib.mapAttrsToList mkCase subcommands)} - *) echo "Usage: ${commandName} []" >&2 - echo >&2 - echo "A tool to manage taskserver users on NixOS" >&2 - echo >&2 - echo "The following subcommands are available:" >&2 - ${lib.concatMapStringsSep "\n " (c: "usage_${mkShellName c}") - (lib.attrNames subcommands)} - exit 1 - esac -'' diff --git a/nixos/modules/services/misc/taskserver/helper-tool.py b/nixos/modules/services/misc/taskserver/helper-tool.py new file mode 100644 index 00000000000..3277a50cd51 --- /dev/null +++ b/nixos/modules/services/misc/taskserver/helper-tool.py @@ -0,0 +1,276 @@ +import grp +import pwd +import os +import re +import string +import subprocess +import sys + +from shutil import rmtree +from tempfile import NamedTemporaryFile + +import click + +CERTTOOL_COMMAND = "@certtool@" +TASKD_COMMAND = "@taskd@" +TASKD_DATA_DIR = "@dataDir@" +TASKD_USER = "@user@" +TASKD_GROUP = "@group@" +FQDN = "@fqdn@" + +RE_CONFIGUSER = re.compile(r'^\s*user\s*=(.*)$') + + +def run_as_taskd_user(): + uid = pwd.getpwnam(TASKD_USER).pw_uid + gid = grp.getgrnam(TASKD_GROUP).gr_gid + os.setgid(gid) + os.setuid(uid) + + +def taskd_cmd(cmd, *args, **kwargs): + return subprocess.call( + [TASKD_COMMAND, cmd, "--data", TASKD_DATA_DIR] + list(args), + preexec_fn=run_as_taskd_user, + **kwargs + ) + + +def label(msg): + if sys.stdout.isatty() or sys.stderr.isatty(): + sys.stderr.write(msg + "\n") + + +def mkpath(*args): + return os.path.join(TASKD_DATA_DIR, "orgs", *args) + + +def fetch_username(org, key): + for line in open(mkpath(org, "users", key, "config"), "r"): + match = RE_CONFIGUSER.match(line) + if match is None: + continue + return match.group(1).strip() + return None + + +def generate_key(org, user): + basedir = os.path.join(TASKD_DATA_DIR, "keys", org, user) + if os.path.exists(basedir): + raise OSError("Keyfile directory for {} already exists.".format(user)) + + privkey = os.path.join(basedir, "private.key") + pubcert = os.path.join(basedir, "public.cert") + cakey = os.path.join(TASKD_DATA_DIR, "keys", "ca.key") + cacert = os.path.join(TASKD_DATA_DIR, "keys", "ca.cert") + + try: + os.makedirs(basedir, mode=0700) + + cmd = [CERTTOOL_COMMAND, "-p", "--bits", "2048", "--outfile", privkey] + subprocess.call(cmd, preexec_fn=lambda: os.umask(0077)) + + template = NamedTemporaryFile(mode="w", prefix="certtool-template") + template.writelines(map(lambda l: l + "\n", [ + "organization = {0}".format(org), + "cn = {}".format(FQDN), + "tls_www_client", + "encryption_key", + "signing_key" + ])) + template.flush() + + cmd = [CERTTOOL_COMMAND, "-c", + "--load-privkey", privkey, + "--load-ca-privkey", cakey, + "--load-ca-certificate", cacert, + "--template", template.name, + "--outfile", pubcert] + subprocess.call(cmd, preexec_fn=lambda: os.umask(0077)) + except: + rmtree(basedir) + raise + + +def is_key_line(line, match): + return line.startswith("---") and line.lstrip("- ").startswith(match) + + +def getkey(*args): + path = os.path.join(TASKD_DATA_DIR, "keys", *args) + buf = [] + for line in open(path, "r"): + if len(buf) == 0: + if is_key_line(line, "BEGIN"): + buf.append(line) + continue + + buf.append(line) + + if is_key_line(line, "END"): + return ''.join(buf) + raise IOError("Unable to get key from {}.".format(path)) + + +def mktaskkey(cfg, path, keydata): + heredoc = 'cat > "{}" <