diff options
Diffstat (limited to 'openvpn/src/openvpn/options.c')
| -rw-r--r-- | openvpn/src/openvpn/options.c | 119 |
1 files changed, 85 insertions, 34 deletions
diff --git a/openvpn/src/openvpn/options.c b/openvpn/src/openvpn/options.c index 525c00c..a2d0f6e 100644 --- a/openvpn/src/openvpn/options.c +++ b/openvpn/src/openvpn/options.c @@ -166,7 +166,7 @@ static const char usage_message[] = " Set n=\"infinite\" to retry indefinitely.\n" "--float : Allow remote to change its IP address/port, such as through\n" " DHCP (this is the default if --remote is not used).\n" - "--ipchange cmd : Execute shell command cmd on remote ip address initial\n" + "--ipchange cmd : Run command cmd on remote ip address initial\n" " setting or change -- execute as: cmd ip-address port#\n" "--port port : TCP/UDP port # for both local and remote.\n" "--lport port : TCP/UDP port # for local (default=%d). Implies --bind.\n" @@ -223,8 +223,8 @@ static const char usage_message[] = " adding routes (may be 0). If not specified, routes will\n" " be added immediately after tun/tap open. On Windows, wait\n" " up to w seconds for TUN/TAP adapter to come up.\n" - "--route-up cmd : Execute shell cmd after routes are added.\n" - "--route-pre-down cmd : Execute shell cmd before routes are removed.\n" + "--route-up cmd : Run command cmd after routes are added.\n" + "--route-pre-down cmd : Run command cmd before routes are removed.\n" "--route-noexec : Don't add routes automatically. Instead pass routes to\n" " --route-up script using environmental variables.\n" "--route-nopull : When used with --client or --pull, accept options pushed\n" @@ -311,17 +311,17 @@ static const char usage_message[] = #endif "--mlock : Disable Paging -- ensures key material and tunnel\n" " data will never be written to disk.\n" - "--up cmd : Shell cmd to execute after successful tun device open.\n" + "--up cmd : Run command cmd after successful tun device open.\n" " Execute as: cmd tun/tap-dev tun-mtu link-mtu \\\n" " ifconfig-local-ip ifconfig-remote-ip\n" " (pre --user or --group UID/GID change)\n" "--up-delay : Delay tun/tap open and possible --up script execution\n" " until after TCP/UDP connection establishment with peer.\n" - "--down cmd : Shell cmd to run after tun device close.\n" + "--down cmd : Run command cmd after tun device close.\n" " (post --user/--group UID/GID change and/or --chroot)\n" - " (script parameters are same as --up option)\n" - "--down-pre : Call --down cmd/script before TUN/TAP close.\n" - "--up-restart : Run up/down scripts for all restarts including those\n" + " (command parameters are same as --up option)\n" + "--down-pre : Run --down command before TUN/TAP close.\n" + "--up-restart : Run up/down commands for all restarts including those\n" " caused by --ping-restart or SIGUSR1\n" "--user user : Set UID to user after initialization.\n" "--group group : Set GID to group after initialization.\n" @@ -452,7 +452,7 @@ static const char usage_message[] = " the authenticated username as the common name,\n" " rather than the common name from the client cert.\n" "--auth-user-pass-verify cmd method: Query client for username/password and\n" - " run script cmd to verify. If method='via-env', pass\n" + " run command cmd to verify. If method='via-env', pass\n" " user/pass via environment, if method='via-file', pass\n" " user/pass via temporary file.\n" "--opt-verify : Clients that connect with options that are incompatible\n" @@ -464,8 +464,8 @@ static const char usage_message[] = "--client-to-client : Internally route client-to-client traffic.\n" "--duplicate-cn : Allow multiple clients with the same common name to\n" " concurrently connect.\n" - "--client-connect cmd : Run script cmd on client connection.\n" - "--client-disconnect cmd : Run script cmd on client disconnection.\n" + "--client-connect cmd : Run command cmd on client connection.\n" + "--client-disconnect cmd : Run command cmd on client disconnection.\n" "--client-config-dir dir : Directory for custom client config files.\n" "--ccd-exclusive : Refuse connection unless custom client config is found.\n" "--tmp-dir dir : Temporary directory, used for --client-connect return file and plugin communication.\n" @@ -475,7 +475,7 @@ static const char usage_message[] = "--tcp-queue-limit n : Maximum number of queued TCP output packets.\n" "--tcp-nodelay : Macro that sets TCP_NODELAY socket flag on the server\n" " as well as pushes it to connecting clients.\n" - "--learn-address cmd : Run script cmd to validate client virtual addresses.\n" + "--learn-address cmd : Run command cmd to validate client virtual addresses.\n" "--connect-freq n s : Allow a maximum of n new connections per s seconds.\n" "--max-clients n : Allow a maximum of n simultaneously connected clients.\n" "--max-routes-per-client n : Allow a maximum of n internal routes per client.\n" @@ -609,7 +609,7 @@ static const char usage_message[] = "--askpass [file]: Get PEM password from controlling tty before we daemonize.\n" "--auth-nocache : Don't cache --askpass or --auth-user-pass passwords.\n" "--crl-verify crl ['dir']: Check peer certificate against a CRL.\n" - "--tls-verify cmd: Execute shell command cmd to verify the X509 name of a\n" + "--tls-verify cmd: Run command cmd to verify the X509 name of a\n" " pending TLS connection that has otherwise passed all other\n" " tests of certification. cmd should return 0 to allow\n" " TLS handshake to proceed, or 1 to fail. (cmd is\n" @@ -2676,6 +2676,55 @@ check_file_access(const int type, const char *file, const int mode, const char * } /* + * Verifies that the path in the "command" that comes after certain script options (e.g., --up) is a + * valid file with appropriate permissions. + * + * "command" consists of a path, optionally followed by a space, which may be + * followed by arbitrary arguments. It is NOT a full shell command line -- shell expansion is not + * performed. + * + * The path and arguments in "command" may be single- or double-quoted or escaped. + * + * The path is extracted from "command", then check_file_access() is called to check it. The + * arguments, if any, are ignored. + * + * Note that the type, mode, and opt arguments to this routine are the same as the corresponding + * check_file_access() arguments. + */ +static bool +check_cmd_access(const char *command, const char *opt) +{ + struct argv argv; + bool return_code; + + /* If no command was set, there are no errors to look for */ + if (! command) + return false; + + /* Extract executable path and arguments */ + argv = argv_new (); + argv_printf (&argv, "%sc", command); + + /* if an executable is specified then check it; otherwise, complain */ + if (argv.argv[0]) + /* Scripts requires R_OK as well, but that might fail on binaries which + * only requires X_OK to function on Unix - a scenario not unlikely to + * be seen on suid binaries. + */ + return_code = check_file_access(CHKACC_FILE, argv.argv[0], X_OK, opt); + else + { + msg (M_NOPREFIX|M_OPTERR, "%s fails with '%s': No path to executable.", + opt, command); + return_code = true; + } + + argv_reset (&argv); + + return return_code; +} + +/* * Sanity check of all file/dir options. Checks that file/dir * is accessible by OpenVPN */ @@ -2751,27 +2800,29 @@ options_postprocess_filechecks (struct options *options) #if P2MP_SERVER errs |= check_file_access (CHKACC_FILE, options->client_config_dir, R_OK|X_OK, "--client-config-dir"); - /* ** Script hooks ** */ - errs |= check_file_access (CHKACC_FILE, options->client_connect_script, - R_OK|X_OK, "--client-connect script"); - errs |= check_file_access (CHKACC_FILE, options->client_disconnect_script, - R_OK|X_OK, "--client-disconnect script"); - errs |= check_file_access (CHKACC_FILE, options->auth_user_pass_verify_script, - R_OK|X_OK, "--auth-user-pass-verify script"); - errs |= check_file_access (CHKACC_FILE, options->tls_verify, - R_OK|X_OK, "--tls-verify script"); - errs |= check_file_access (CHKACC_FILE, options->up_script, - R_OK|X_OK, "--up script"); - errs |= check_file_access (CHKACC_FILE, options->down_script, - R_OK|X_OK, "--down script"); - errs |= check_file_access (CHKACC_FILE, options->ipchange, - R_OK|X_OK, "--ipchange script"); - errs |= check_file_access (CHKACC_FILE, options->route_script, - R_OK|X_OK, "--route-up script"); - errs |= check_file_access (CHKACC_FILE, options->route_predown_script, - R_OK|X_OK, "--route-pre-down script"); - errs |= check_file_access (CHKACC_FILE, options->learn_address_script, - R_OK|X_OK, "--learn-address script"); + + /* ** Script hooks that accept an optionally quoted and/or escaped executable path, ** */ + /* ** optionally followed by arguments ** */ + errs |= check_cmd_access (options->auth_user_pass_verify_script, + "--auth-user-pass-verify script"); + errs |= check_cmd_access (options->client_connect_script, + "--client-connect script"); + errs |= check_cmd_access (options->client_disconnect_script, + "--client-disconnect script"); + errs |= check_cmd_access (options->tls_verify, + "--tls-verify script"); + errs |= check_cmd_access (options->up_script, + "--up script"); + errs |= check_cmd_access (options->down_script, + "--down script"); + errs |= check_cmd_access (options->ipchange, + "--ipchange script"); + errs |= check_cmd_access (options->route_script, + "--route-up script"); + errs |= check_cmd_access (options->route_predown_script, + "--route-pre-down script"); + errs |= check_cmd_access (options->learn_address_script, + "--learn-address script"); #endif /* P2MP_SERVER */ if (errs) |