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See http://spamassassin.org/tag/ for more details. 0.0 URIBL_BLOCKED ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [URIs: rfc2549.org] 0.2 HEADER_FROM_DIFFERENT_DOMAINS From and EnvelopeFrom 2nd level mail domains are different 0.0 SPF_NONE SPF: sender does not publish an SPF Record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record X-Headers-End: 1lUARK-00H1o9-H2 Subject: [Openvpn-devel] [PATCH v6] Implement deferred auth for scripts X-BeenThere: openvpn-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: openvpn-devel-bounces@lists.sourceforge.net X-getmail-retrieved-from-mailbox: Inbox This patch also refactors the if condition that checks the result of the authentication since that has become quite unreadable. It renames s1/s2 and extracts some parts of the condition into individual variables to make the condition better understandle Patch v2: add refactoring of the if condition Patch v4: fix documentation not mentioning method as 2nd line Patch v5: fix deferred auth used by both plugin and script not working Patch v6: Add missing async inotify for script deferred auth Signed-off-by: Arne Schwabe Tested-by: Antonio Quartulli Acked-by: Gert Doering --- Changes.rst | 10 +++ doc/man-sections/script-options.rst | 14 +++- src/openvpn/multi.c | 6 ++ src/openvpn/ssl.c | 1 + src/openvpn/ssl_common.h | 1 + src/openvpn/ssl_verify.c | 105 ++++++++++++++++++++-------- 6 files changed, 106 insertions(+), 31 deletions(-) diff --git a/Changes.rst b/Changes.rst index 457dfc07e..9185b55f7 100644 --- a/Changes.rst +++ b/Changes.rst @@ -30,6 +30,16 @@ TLS mode with self-signed certificates become optional. This allows for small OpenVPN setups without setting up a PKI with Easy-RSA or similar software. +Deferred auth support for scripts + The ``--auth-user-pass-verify`` script supports now deferred authentication. + +Pending auth support for plugins and scripts + Both auth plugin and script can now signal pending authentication to + the client when using deferred authentication. The new ``client-crresponse`` + script option and ``OPENVPN_PLUGIN_CLIENT_CRRESPONSE`` plugin function can + be used to parse a client response to a ``CR_TEXT`` two factor challenge. + + See ``sample/sample-scripts/totpauth.py`` for an example. Deprecated features ------------------- diff --git a/doc/man-sections/script-options.rst b/doc/man-sections/script-options.rst index 03b3dd77b..22990f4f4 100644 --- a/doc/man-sections/script-options.rst +++ b/doc/man-sections/script-options.rst @@ -90,7 +90,19 @@ SCRIPT HOOKS The script should examine the username and password, returning a success exit code (:code:`0`) if the client's authentication request is to be - accepted, or a failure code (:code:`1`) to reject the client. + accepted, a failure code (:code:`1`) to reject the client, or a that + the authentication is deferred (:code:`2`). If the authentication is + deferred, the script must fork/start a background or another non-blocking + operation to continue the authentication in the background. When finshing + the authentication, a :code:`1` or :code:`0` must be written to the + file specified by the :code:`auth_control_file`. + + When deferred authentication is in use, the script can also request + pending authentication by writing to the file specified by the + :code:`auth_pending_file`. The first line must be the timeout in + seconds, the required method on the second line (e.g. crtext) and + third line must be the EXTRA as documented in the + ``client-pending-auth`` section of `doc/management.txt`. This directive is designed to enable a plugin-style interface for extending OpenVPN's authentication capabilities. diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c index 7c9500f3e..e5e466631 100644 --- a/src/openvpn/multi.c +++ b/src/openvpn/multi.c @@ -2990,6 +2990,12 @@ multi_process_post(struct multi_context *m, struct multi_instance *mi, const uns add_inotify_file_watch(m, mi, m->top.c2.inotify_fd, ks->plugin_auth.auth_control_file); } + if (ks && ks->script_auth.auth_control_file && was_unauthenticated + && (ks->authenticated == KS_AUTH_DEFERRED)) + { + add_inotify_file_watch(m, mi, m->top.c2.inotify_fd, + ks->script_auth.auth_control_file); + } #endif if (!IS_SIG(&mi->context)) diff --git a/src/openvpn/ssl.c b/src/openvpn/ssl.c index d8662d000..b27a78b3d 100644 --- a/src/openvpn/ssl.c +++ b/src/openvpn/ssl.c @@ -994,6 +994,7 @@ key_state_free(struct key_state *ks, bool clear) packet_id_free(&ks->crypto_options.packet_id); key_state_rm_auth_control_files(&ks->plugin_auth); + key_state_rm_auth_control_files(&ks->script_auth); if (clear) { diff --git a/src/openvpn/ssl_common.h b/src/openvpn/ssl_common.h index b2fa44e56..acb815955 100644 --- a/src/openvpn/ssl_common.h +++ b/src/openvpn/ssl_common.h @@ -222,6 +222,7 @@ struct key_state time_t acf_last_mod; struct auth_deferred_status plugin_auth; + struct auth_deferred_status script_auth; }; /** Control channel wrapping (--tls-auth/--tls-crypt) context */ diff --git a/src/openvpn/ssl_verify.c b/src/openvpn/ssl_verify.c index 7608155cd..7c02d46ce 100644 --- a/src/openvpn/ssl_verify.c +++ b/src/openvpn/ssl_verify.c @@ -1102,20 +1102,25 @@ tls_authentication_status(struct tls_multi *multi, const int latency) } else { - unsigned int s1 = ACF_DISABLED; - unsigned int s2 = ACF_DISABLED; - s1 = key_state_test_auth_control_file(&ks->plugin_auth); + unsigned int auth_plugin = ACF_DISABLED; + unsigned int auth_script = ACF_DISABLED; + unsigned int auth_man = ACF_DISABLED; + auth_plugin = key_state_test_auth_control_file(&ks->plugin_auth); + auth_script = key_state_test_auth_control_file(&ks->script_auth); #ifdef ENABLE_MANAGEMENT - s2 = man_def_auth_test(ks); + auth_man = man_def_auth_test(ks); #endif - ASSERT(s1 < 4 && s2 < 4); + ASSERT(auth_plugin < 4 && auth_script < 4 && auth_man < 4); - if (s1 == ACF_FAILED || s2 == ACF_FAILED) + if (auth_plugin == ACF_FAILED || auth_script == ACF_FAILED + || auth_man == ACF_FAILED) { ks->authenticated = KS_AUTH_FALSE; failed_auth = true; } - else if (s1 == ACF_UNDEFINED || s2 == ACF_UNDEFINED) + else if (auth_plugin == ACF_UNDEFINED + || auth_script == ACF_UNDEFINED + || auth_man == ACF_UNDEFINED) { if (now < ks->auth_deferred_expire) { @@ -1124,7 +1129,7 @@ tls_authentication_status(struct tls_multi *multi, const int latency) } else { - /* s1 and s2 are either ACF_DISABLED or ACF_SUCCEDED */ + /* auth_plugin and auth_man are either ACF_DISABLED or ACF_SUCCEDED */ success = true; ks->authenticated = KS_AUTH_TRUE; } @@ -1204,14 +1209,15 @@ tls_authenticate_key(struct tls_multi *multi, const unsigned int mda_key_id, con /* * Verify the user name and password using a script */ -static bool +static int verify_user_pass_script(struct tls_session *session, struct tls_multi *multi, const struct user_pass *up) { struct gc_arena gc = gc_new(); struct argv argv = argv_new(); const char *tmp_file = ""; - bool ret = false; + int retval = OPENVPN_PLUGIN_FUNC_ERROR; + struct key_state *ks = &session->key[KS_PRIMARY]; /* primary key */ /* Set environmental variables prior to calling script */ setenv_str(session->opt->es, "script_type", "user-pass-verify"); @@ -1239,25 +1245,58 @@ verify_user_pass_script(struct tls_session *session, struct tls_multi *multi, /* pass temp file name to script */ argv_printf_cat(&argv, "%s", tmp_file); } - else - { - msg(D_TLS_ERRORS, "TLS Auth Error: could not create write " - "username/password to temp file"); - } } else { + setenv_str(session->opt->es, "username", up->username); setenv_str(session->opt->es, "password", up->password); } + /* generate filename for deferred auth control file */ + if (!key_state_gen_auth_control_files(&ks->script_auth, session->opt)) + { + msg(D_TLS_ERRORS, "TLS Auth Error (%s): " + "could not create deferred auth control file", __func__); + return OPENVPN_PLUGIN_FUNC_ERROR; + } + /* call command */ - ret = openvpn_run_script(&argv, session->opt->es, 0, - "--auth-user-pass-verify"); + int script_ret = openvpn_run_script(&argv, session->opt->es, S_EXITCODE, + "--auth-user-pass-verify"); + switch (script_ret) + { + case 0: + retval = OPENVPN_PLUGIN_FUNC_SUCCESS; + break; + case 2: + retval = OPENVPN_PLUGIN_FUNC_DEFERRED; + break; + default: + retval = OPENVPN_PLUGIN_FUNC_ERROR; + break; + } + if (retval == OPENVPN_PLUGIN_FUNC_DEFERRED) + { + /* Check if we the plugin has written the pending auth control + * file and send the pending auth to the client */ + if(!key_state_check_auth_pending_file(&ks->script_auth, + multi)) + { + retval = OPENVPN_PLUGIN_FUNC_ERROR; + key_state_rm_auth_control_files(&ks->script_auth); + } + } + else + { + /* purge auth control filename (and file itself) for non-deferred returns */ + key_state_rm_auth_control_files(&ks->script_auth); + } if (!session->opt->auth_user_pass_verify_script_via_file) { setenv_del(session->opt->es, "password"); } + done: if (tmp_file && strlen(tmp_file) > 0) { @@ -1266,7 +1305,7 @@ done: argv_free(&argv); gc_free(&gc); - return ret; + return retval; } /* @@ -1387,8 +1426,6 @@ void verify_user_pass(struct user_pass *up, struct tls_multi *multi, struct tls_session *session) { - int s1 = OPENVPN_PLUGIN_FUNC_SUCCESS; - bool s2 = true; struct key_state *ks = &session->key[KS_PRIMARY]; /* primary key */ #ifdef ENABLE_MANAGEMENT @@ -1448,30 +1485,32 @@ verify_user_pass(struct user_pass *up, struct tls_multi *multi, } } + int plugin_status = OPENVPN_PLUGIN_FUNC_SUCCESS; + int script_status = OPENVPN_PLUGIN_FUNC_SUCCESS; /* Set the environment variables used by all auth variants */ if (!set_verify_user_pass_env(up, multi, session)) { skip_auth = true; - s1 = OPENVPN_PLUGIN_FUNC_ERROR; + plugin_status = OPENVPN_PLUGIN_FUNC_ERROR; } /* call plugin(s) and/or script */ if (!skip_auth) { #ifdef ENABLE_MANAGEMENT - if (man_def_auth==KMDA_DEF) + if (man_def_auth == KMDA_DEF) { man_def_auth = verify_user_pass_management(session, multi, up); } #endif if (plugin_defined(session->opt->plugins, OPENVPN_PLUGIN_AUTH_USER_PASS_VERIFY)) { - s1 = verify_user_pass_plugin(session, multi, up); + plugin_status = verify_user_pass_plugin(session, multi, up); } if (session->opt->auth_user_pass_verify_script) { - s2 = verify_user_pass_script(session, multi, up); + script_status = verify_user_pass_script(session, multi, up); } } @@ -1482,19 +1521,25 @@ verify_user_pass(struct user_pass *up, struct tls_multi *multi, msg(D_TLS_ERRORS, "TLS Auth Error: --username-as-common name specified and username is longer than the maximum permitted Common Name length of %d characters", TLS_USERNAME_LEN); - s1 = OPENVPN_PLUGIN_FUNC_ERROR; + plugin_status = OPENVPN_PLUGIN_FUNC_ERROR; + script_status = OPENVPN_PLUGIN_FUNC_ERROR; } /* auth succeeded? */ - if ((s1 == OPENVPN_PLUGIN_FUNC_SUCCESS - || s1 == OPENVPN_PLUGIN_FUNC_DEFERRED - ) && s2 + bool plugin_ok = plugin_status == OPENVPN_PLUGIN_FUNC_SUCCESS + || plugin_status == OPENVPN_PLUGIN_FUNC_DEFERRED; + + bool script_ok = script_status == OPENVPN_PLUGIN_FUNC_SUCCESS + || script_status == OPENVPN_PLUGIN_FUNC_DEFERRED; + + if (script_ok && plugin_ok && tls_lock_username(multi, up->username) #ifdef ENABLE_MANAGEMENT && man_def_auth != KMDA_ERROR #endif - && tls_lock_username(multi, up->username)) + ) { ks->authenticated = KS_AUTH_TRUE; - if (s1 == OPENVPN_PLUGIN_FUNC_DEFERRED) + if (plugin_status == OPENVPN_PLUGIN_FUNC_DEFERRED + || script_status == OPENVPN_PLUGIN_FUNC_DEFERRED) { ks->authenticated = KS_AUTH_DEFERRED; }