/* GDBus - GLib D-Bus Library * * Copyright (C) 2008-2010 Red Hat, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General * Public License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place, Suite 330, * Boston, MA 02111-1307, USA. * * Author: David Zeuthen */ #include "config.h" #include "gdbusauth.h" #include "gdbusauthmechanismanon.h" #include "gdbusauthmechanismexternal.h" #include "gdbusauthmechanismsha1.h" #include "gdbusauthobserver.h" #include "gdbuserror.h" #include "gdbusutils.h" #include "gioenumtypes.h" #include "gcredentials.h" #include "gdbusprivate.h" #include "giostream.h" #include "gdatainputstream.h" #include "gdataoutputstream.h" #ifdef G_OS_UNIX #include "gnetworking.h" #include "gunixconnection.h" #include "gunixcredentialsmessage.h" #endif #include "glibintl.h" static void debug_print (const gchar *message, ...) { if (G_UNLIKELY (_g_dbus_debug_authentication ())) { gchar *s; GString *str; va_list var_args; guint n; _g_dbus_debug_print_lock (); va_start (var_args, message); s = g_strdup_vprintf (message, var_args); va_end (var_args); str = g_string_new (NULL); for (n = 0; s[n] != '\0'; n++) { if (G_UNLIKELY (s[n] == '\r')) g_string_append (str, "\\r"); else if (G_UNLIKELY (s[n] == '\n')) g_string_append (str, "\\n"); else g_string_append_c (str, s[n]); } g_print ("GDBus-debug:Auth: %s\n", str->str); g_string_free (str, TRUE); g_free (s); _g_dbus_debug_print_unlock (); } } typedef struct { const gchar *name; gint priority; GType gtype; } Mechanism; static void mechanism_free (Mechanism *m); struct _GDBusAuthPrivate { GIOStream *stream; /* A list of available Mechanism, sorted according to priority */ GList *available_mechanisms; }; enum { PROP_0, PROP_STREAM }; G_DEFINE_TYPE (GDBusAuth, _g_dbus_auth, G_TYPE_OBJECT); /* ---------------------------------------------------------------------------------------------------- */ static void _g_dbus_auth_finalize (GObject *object) { GDBusAuth *auth = G_DBUS_AUTH (object); if (auth->priv->stream != NULL) g_object_unref (auth->priv->stream); g_list_free_full (auth->priv->available_mechanisms, (GDestroyNotify) mechanism_free); if (G_OBJECT_CLASS (_g_dbus_auth_parent_class)->finalize != NULL) G_OBJECT_CLASS (_g_dbus_auth_parent_class)->finalize (object); } static void _g_dbus_auth_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec) { GDBusAuth *auth = G_DBUS_AUTH (object); switch (prop_id) { case PROP_STREAM: g_value_set_object (value, auth->priv->stream); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void _g_dbus_auth_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec) { GDBusAuth *auth = G_DBUS_AUTH (object); switch (prop_id) { case PROP_STREAM: auth->priv->stream = g_value_dup_object (value); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void _g_dbus_auth_class_init (GDBusAuthClass *klass) { GObjectClass *gobject_class; g_type_class_add_private (klass, sizeof (GDBusAuthPrivate)); gobject_class = G_OBJECT_CLASS (klass); gobject_class->get_property = _g_dbus_auth_get_property; gobject_class->set_property = _g_dbus_auth_set_property; gobject_class->finalize = _g_dbus_auth_finalize; g_object_class_install_property (gobject_class, PROP_STREAM, g_param_spec_object ("stream", P_("IO Stream"), P_("The underlying GIOStream used for I/O"), G_TYPE_IO_STREAM, G_PARAM_READABLE | G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_NAME | G_PARAM_STATIC_BLURB | G_PARAM_STATIC_NICK)); } static void mechanism_free (Mechanism *m) { g_free (m); } static void add_mechanism (GDBusAuth *auth, GDBusAuthObserver *observer, GType mechanism_type) { const gchar *name; name = _g_dbus_auth_mechanism_get_name (mechanism_type); if (observer == NULL || g_dbus_auth_observer_allow_mechanism (observer, name)) { Mechanism *m; m = g_new0 (Mechanism, 1); m->name = name; m->priority = _g_dbus_auth_mechanism_get_priority (mechanism_type); m->gtype = mechanism_type; auth->priv->available_mechanisms = g_list_prepend (auth->priv->available_mechanisms, m); } } static gint mech_compare_func (Mechanism *a, Mechanism *b) { gint ret; /* ensure deterministic order */ ret = b->priority - a->priority; if (ret == 0) ret = g_strcmp0 (b->name, a->name); return ret; } static void _g_dbus_auth_init (GDBusAuth *auth) { auth->priv = G_TYPE_INSTANCE_GET_PRIVATE (auth, G_TYPE_DBUS_AUTH, GDBusAuthPrivate); } static void _g_dbus_auth_add_mechs (GDBusAuth *auth, GDBusAuthObserver *observer) { /* TODO: trawl extension points */ add_mechanism (auth, observer, G_TYPE_DBUS_AUTH_MECHANISM_ANON); add_mechanism (auth, observer, G_TYPE_DBUS_AUTH_MECHANISM_SHA1); add_mechanism (auth, observer, G_TYPE_DBUS_AUTH_MECHANISM_EXTERNAL); auth->priv->available_mechanisms = g_list_sort (auth->priv->available_mechanisms, (GCompareFunc) mech_compare_func); } static GType find_mech_by_name (GDBusAuth *auth, const gchar *name) { GType ret; GList *l; ret = (GType) 0; for (l = auth->priv->available_mechanisms; l != NULL; l = l->next) { Mechanism *m = l->data; if (g_strcmp0 (name, m->name) == 0) { ret = m->gtype; goto out; } } out: return ret; } GDBusAuth * _g_dbus_auth_new (GIOStream *stream) { return g_object_new (G_TYPE_DBUS_AUTH, "stream", stream, NULL); } /* ---------------------------------------------------------------------------------------------------- */ /* like g_data_input_stream_read_line() but sets error if there's no content to read */ static gchar * _my_g_data_input_stream_read_line (GDataInputStream *dis, gsize *out_line_length, GCancellable *cancellable, GError **error) { gchar *ret; g_return_val_if_fail (error == NULL || *error == NULL, NULL); ret = g_data_input_stream_read_line (dis, out_line_length, cancellable, error); if (ret == NULL && error != NULL && *error == NULL) { g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED, _("Unexpected lack of content trying to read a line")); } return ret; } /* This function is to avoid situations like this * * BEGIN\r\nl\0\0\1... * * e.g. where we read into the first D-Bus message while waiting for * the final line from the client (TODO: file bug against gio for * this) */ static gchar * _my_g_input_stream_read_line_safe (GInputStream *i, gsize *out_line_length, GCancellable *cancellable, GError **error) { GString *str; gchar c; gssize num_read; gboolean last_was_cr; str = g_string_new (NULL); last_was_cr = FALSE; while (TRUE) { num_read = g_input_stream_read (i, &c, 1, cancellable, error); if (num_read == -1) goto fail; if (num_read == 0) { if (error != NULL && *error == NULL) { g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED, _("Unexpected lack of content trying to (safely) read a line")); } goto fail; } g_string_append_c (str, (gint) c); if (last_was_cr) { if (c == 0x0a) { g_assert (str->len >= 2); g_string_set_size (str, str->len - 2); goto out; } } last_was_cr = (c == 0x0d); } out: if (out_line_length != NULL) *out_line_length = str->len; return g_string_free (str, FALSE); fail: g_assert (error == NULL || *error != NULL); g_string_free (str, TRUE); return NULL; } /* ---------------------------------------------------------------------------------------------------- */ static void append_nibble (GString *s, gint val) { g_string_append_c (s, val >= 10 ? ('a' + val - 10) : ('0' + val)); } static gchar * hexdecode (const gchar *str, gsize *out_len, GError **error) { gchar *ret; GString *s; guint n; ret = NULL; s = g_string_new (NULL); for (n = 0; str[n] != '\0'; n += 2) { gint upper_nibble; gint lower_nibble; guint value; upper_nibble = g_ascii_xdigit_value (str[n]); lower_nibble = g_ascii_xdigit_value (str[n + 1]); if (upper_nibble == -1 || lower_nibble == -1) { g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, "Error hexdecoding string `%s' around position %d", str, n); goto out; } value = (upper_nibble<<4) | lower_nibble; g_string_append_c (s, value); } ret = g_string_free (s, FALSE); s = NULL; out: if (s != NULL) g_string_free (s, TRUE); return ret; } /* TODO: take len */ static gchar * hexencode (const gchar *str) { guint n; GString *s; s = g_string_new (NULL); for (n = 0; str[n] != '\0'; n++) { gint val; gint upper_nibble; gint lower_nibble; val = ((const guchar *) str)[n]; upper_nibble = val >> 4; lower_nibble = val & 0x0f; append_nibble (s, upper_nibble); append_nibble (s, lower_nibble); } return g_string_free (s, FALSE); } /* ---------------------------------------------------------------------------------------------------- */ static GDBusAuthMechanism * client_choose_mech_and_send_initial_response (GDBusAuth *auth, GCredentials *credentials_that_were_sent, const gchar* const *supported_auth_mechs, GPtrArray *attempted_auth_mechs, GDataOutputStream *dos, GCancellable *cancellable, GError **error) { GDBusAuthMechanism *mech; GType auth_mech_to_use_gtype; guint n; guint m; gchar *initial_response; gsize initial_response_len; gchar *encoded; gchar *s; again: mech = NULL; debug_print ("CLIENT: Trying to choose mechanism"); /* find an authentication mechanism to try, if any */ auth_mech_to_use_gtype = (GType) 0; for (n = 0; supported_auth_mechs[n] != NULL; n++) { gboolean attempted_already; attempted_already = FALSE; for (m = 0; m < attempted_auth_mechs->len; m++) { if (g_strcmp0 (supported_auth_mechs[n], attempted_auth_mechs->pdata[m]) == 0) { attempted_already = TRUE; break; } } if (!attempted_already) { auth_mech_to_use_gtype = find_mech_by_name (auth, supported_auth_mechs[n]); if (auth_mech_to_use_gtype != (GType) 0) break; } } if (auth_mech_to_use_gtype == (GType) 0) { guint n; gchar *available; GString *tried_str; debug_print ("CLIENT: Exhausted all available mechanisms"); available = g_strjoinv (", ", (gchar **) supported_auth_mechs); tried_str = g_string_new (NULL); for (n = 0; n < attempted_auth_mechs->len; n++) { if (n > 0) g_string_append (tried_str, ", "); g_string_append (tried_str, attempted_auth_mechs->pdata[n]); } g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, _("Exhausted all available authentication mechanisms (tried: %s) (available: %s)"), tried_str->str, available); g_string_free (tried_str, TRUE); g_free (available); goto out; } /* OK, decided on a mechanism - let's do this thing */ mech = g_object_new (auth_mech_to_use_gtype, "stream", auth->priv->stream, "credentials", credentials_that_were_sent, NULL); debug_print ("CLIENT: Trying mechanism `%s'", _g_dbus_auth_mechanism_get_name (auth_mech_to_use_gtype)); g_ptr_array_add (attempted_auth_mechs, (gpointer) _g_dbus_auth_mechanism_get_name (auth_mech_to_use_gtype)); /* the auth mechanism may not be supported * (for example, EXTERNAL only works if credentials were exchanged) */ if (!_g_dbus_auth_mechanism_is_supported (mech)) { debug_print ("CLIENT: Mechanism `%s' says it is not supported", _g_dbus_auth_mechanism_get_name (auth_mech_to_use_gtype)); g_object_unref (mech); mech = NULL; goto again; } initial_response_len = -1; initial_response = _g_dbus_auth_mechanism_client_initiate (mech, &initial_response_len); #if 0 g_printerr ("using auth mechanism with name `%s' of type `%s' with initial response `%s'\n", _g_dbus_auth_mechanism_get_name (auth_mech_to_use_gtype), g_type_name (G_TYPE_FROM_INSTANCE (mech)), initial_response); #endif if (initial_response != NULL) { //g_printerr ("initial_response = `%s'\n", initial_response); encoded = hexencode (initial_response); s = g_strdup_printf ("AUTH %s %s\r\n", _g_dbus_auth_mechanism_get_name (auth_mech_to_use_gtype), encoded); g_free (initial_response); g_free (encoded); } else { s = g_strdup_printf ("AUTH %s\r\n", _g_dbus_auth_mechanism_get_name (auth_mech_to_use_gtype)); } debug_print ("CLIENT: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) { g_object_unref (mech); mech = NULL; g_free (s); goto out; } g_free (s); out: return mech; } /* ---------------------------------------------------------------------------------------------------- */ typedef enum { CLIENT_STATE_WAITING_FOR_DATA, CLIENT_STATE_WAITING_FOR_OK, CLIENT_STATE_WAITING_FOR_REJECT, CLIENT_STATE_WAITING_FOR_AGREE_UNIX_FD } ClientState; gchar * _g_dbus_auth_run_client (GDBusAuth *auth, GDBusAuthObserver *observer, GDBusCapabilityFlags offered_capabilities, GDBusCapabilityFlags *out_negotiated_capabilities, GCancellable *cancellable, GError **error) { gchar *s; GDataInputStream *dis; GDataOutputStream *dos; GCredentials *credentials; gchar *ret_guid; gchar *line; gsize line_length; gchar **supported_auth_mechs; GPtrArray *attempted_auth_mechs; GDBusAuthMechanism *mech; ClientState state; GDBusCapabilityFlags negotiated_capabilities; debug_print ("CLIENT: initiating"); _g_dbus_auth_add_mechs (auth, observer); ret_guid = NULL; supported_auth_mechs = NULL; attempted_auth_mechs = g_ptr_array_new (); mech = NULL; negotiated_capabilities = 0; credentials = NULL; dis = G_DATA_INPUT_STREAM (g_data_input_stream_new (g_io_stream_get_input_stream (auth->priv->stream))); dos = G_DATA_OUTPUT_STREAM (g_data_output_stream_new (g_io_stream_get_output_stream (auth->priv->stream))); g_filter_input_stream_set_close_base_stream (G_FILTER_INPUT_STREAM (dis), FALSE); g_filter_output_stream_set_close_base_stream (G_FILTER_OUTPUT_STREAM (dos), FALSE); g_data_input_stream_set_newline_type (dis, G_DATA_STREAM_NEWLINE_TYPE_CR_LF); #ifdef G_OS_UNIX if (G_IS_UNIX_CONNECTION (auth->priv->stream)) { credentials = g_credentials_new (); if (!g_unix_connection_send_credentials (G_UNIX_CONNECTION (auth->priv->stream), cancellable, error)) goto out; } else { if (!g_data_output_stream_put_byte (dos, '\0', cancellable, error)) goto out; } #else if (!g_data_output_stream_put_byte (dos, '\0', cancellable, error)) goto out; #endif if (credentials != NULL) { if (G_UNLIKELY (_g_dbus_debug_authentication ())) { s = g_credentials_to_string (credentials); debug_print ("CLIENT: sent credentials `%s'", s); g_free (s); } } else { debug_print ("CLIENT: didn't send any credentials"); } /* TODO: to reduce roundtrips, try to pick an auth mechanism to start with */ /* Get list of supported authentication mechanisms */ s = "AUTH\r\n"; debug_print ("CLIENT: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) goto out; state = CLIENT_STATE_WAITING_FOR_REJECT; while (TRUE) { switch (state) { case CLIENT_STATE_WAITING_FOR_REJECT: debug_print ("CLIENT: WaitingForReject"); line = _my_g_data_input_stream_read_line (dis, &line_length, cancellable, error); if (line == NULL) goto out; debug_print ("CLIENT: WaitingForReject, read '%s'", line); choose_mechanism: if (!g_str_has_prefix (line, "REJECTED ")) { g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, "In WaitingForReject: Expected `REJECTED am1 am2 ... amN', got `%s'", line); g_free (line); goto out; } if (supported_auth_mechs == NULL) { supported_auth_mechs = g_strsplit (line + sizeof ("REJECTED ") - 1, " ", 0); #if 0 for (n = 0; supported_auth_mechs != NULL && supported_auth_mechs[n] != NULL; n++) g_printerr ("supported_auth_mechs[%d] = `%s'\n", n, supported_auth_mechs[n]); #endif } g_free (line); mech = client_choose_mech_and_send_initial_response (auth, credentials, (const gchar* const *) supported_auth_mechs, attempted_auth_mechs, dos, cancellable, error); if (mech == NULL) goto out; if (_g_dbus_auth_mechanism_client_get_state (mech) == G_DBUS_AUTH_MECHANISM_STATE_WAITING_FOR_DATA) state = CLIENT_STATE_WAITING_FOR_DATA; else state = CLIENT_STATE_WAITING_FOR_OK; break; case CLIENT_STATE_WAITING_FOR_OK: debug_print ("CLIENT: WaitingForOK"); line = _my_g_data_input_stream_read_line (dis, &line_length, cancellable, error); if (line == NULL) goto out; debug_print ("CLIENT: WaitingForOK, read `%s'", line); if (g_str_has_prefix (line, "OK ")) { if (!g_dbus_is_guid (line + 3)) { g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, "Invalid OK response `%s'", line); g_free (line); goto out; } ret_guid = g_strdup (line + 3); g_free (line); if (offered_capabilities & G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING) { s = "NEGOTIATE_UNIX_FD\r\n"; debug_print ("CLIENT: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) goto out; state = CLIENT_STATE_WAITING_FOR_AGREE_UNIX_FD; } else { s = "BEGIN\r\n"; debug_print ("CLIENT: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) goto out; /* and we're done! */ goto out; } } else if (g_str_has_prefix (line, "REJECTED ")) { goto choose_mechanism; } else { /* TODO: handle other valid responses */ g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, "In WaitingForOk: unexpected response `%s'", line); g_free (line); goto out; } break; case CLIENT_STATE_WAITING_FOR_AGREE_UNIX_FD: debug_print ("CLIENT: WaitingForAgreeUnixFD"); line = _my_g_data_input_stream_read_line (dis, &line_length, cancellable, error); if (line == NULL) goto out; debug_print ("CLIENT: WaitingForAgreeUnixFD, read=`%s'", line); if (g_strcmp0 (line, "AGREE_UNIX_FD") == 0) { g_free (line); negotiated_capabilities |= G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING; s = "BEGIN\r\n"; debug_print ("CLIENT: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) goto out; /* and we're done! */ goto out; } else if (g_str_has_prefix (line, "ERROR") && (line[5] == 0 || g_ascii_isspace (line[5]))) { //g_strstrip (line + 5); g_debug ("bah, no unix_fd: `%s'", line + 5); g_free (line); s = "BEGIN\r\n"; debug_print ("CLIENT: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) goto out; /* and we're done! */ goto out; } else { /* TODO: handle other valid responses */ g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, "In WaitingForAgreeUnixFd: unexpected response `%s'", line); g_free (line); goto out; } break; case CLIENT_STATE_WAITING_FOR_DATA: debug_print ("CLIENT: WaitingForData"); line = _my_g_data_input_stream_read_line (dis, &line_length, cancellable, error); if (line == NULL) goto out; debug_print ("CLIENT: WaitingForData, read=`%s'", line); if (g_str_has_prefix (line, "DATA ")) { gchar *encoded; gchar *decoded_data; gsize decoded_data_len = 0; encoded = g_strdup (line + 5); g_free (line); g_strstrip (encoded); decoded_data = hexdecode (encoded, &decoded_data_len, error); g_free (encoded); if (decoded_data == NULL) { g_prefix_error (error, "DATA response is malformed: "); /* invalid encoding, disconnect! */ goto out; } _g_dbus_auth_mechanism_client_data_receive (mech, decoded_data, decoded_data_len); g_free (decoded_data); if (_g_dbus_auth_mechanism_client_get_state (mech) == G_DBUS_AUTH_MECHANISM_STATE_HAVE_DATA_TO_SEND) { gchar *data; gsize data_len; gchar *encoded_data; data = _g_dbus_auth_mechanism_client_data_send (mech, &data_len); encoded_data = hexencode (data); s = g_strdup_printf ("DATA %s\r\n", encoded_data); g_free (encoded_data); g_free (data); debug_print ("CLIENT: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) { g_free (s); goto out; } g_free (s); } state = CLIENT_STATE_WAITING_FOR_OK; } else if (g_str_has_prefix (line, "REJECTED ")) { /* could be the chosen authentication method just doesn't work. Try * another one... */ goto choose_mechanism; } else { g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, "In WaitingForData: unexpected response `%s'", line); g_free (line); goto out; } break; default: g_assert_not_reached (); break; } }; /* main authentication client loop */ out: if (mech != NULL) g_object_unref (mech); g_ptr_array_unref (attempted_auth_mechs); g_strfreev (supported_auth_mechs); g_object_unref (dis); g_object_unref (dos); /* ensure return value is NULL if error is set */ if (error != NULL && *error != NULL) { g_free (ret_guid); ret_guid = NULL; } if (ret_guid != NULL) { if (out_negotiated_capabilities != NULL) *out_negotiated_capabilities = negotiated_capabilities; } if (credentials != NULL) g_object_unref (credentials); debug_print ("CLIENT: Done, authenticated=%d", ret_guid != NULL); return ret_guid; } /* ---------------------------------------------------------------------------------------------------- */ static gchar * get_auth_mechanisms (GDBusAuth *auth, gboolean allow_anonymous, const gchar *prefix, const gchar *suffix, const gchar *separator) { GList *l; GString *str; gboolean need_sep; str = g_string_new (prefix); need_sep = FALSE; for (l = auth->priv->available_mechanisms; l != NULL; l = l->next) { Mechanism *m = l->data; if (!allow_anonymous && g_strcmp0 (m->name, "ANONYMOUS") == 0) continue; if (need_sep) g_string_append (str, separator); g_string_append (str, m->name); need_sep = TRUE; } g_string_append (str, suffix); return g_string_free (str, FALSE); } typedef enum { SERVER_STATE_WAITING_FOR_AUTH, SERVER_STATE_WAITING_FOR_DATA, SERVER_STATE_WAITING_FOR_BEGIN } ServerState; gboolean _g_dbus_auth_run_server (GDBusAuth *auth, GDBusAuthObserver *observer, const gchar *guid, gboolean allow_anonymous, GDBusCapabilityFlags offered_capabilities, GDBusCapabilityFlags *out_negotiated_capabilities, GCredentials **out_received_credentials, GCancellable *cancellable, GError **error) { gboolean ret; ServerState state; GDataInputStream *dis; GDataOutputStream *dos; GError *local_error; guchar byte; gchar *line; gsize line_length; GDBusAuthMechanism *mech; gchar *s; GDBusCapabilityFlags negotiated_capabilities; GCredentials *credentials; debug_print ("SERVER: initiating"); _g_dbus_auth_add_mechs (auth, observer); ret = FALSE; dis = NULL; dos = NULL; mech = NULL; negotiated_capabilities = 0; credentials = NULL; if (!g_dbus_is_guid (guid)) { g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, "The given guid `%s' is not valid", guid); goto out; } dis = G_DATA_INPUT_STREAM (g_data_input_stream_new (g_io_stream_get_input_stream (auth->priv->stream))); dos = G_DATA_OUTPUT_STREAM (g_data_output_stream_new (g_io_stream_get_output_stream (auth->priv->stream))); g_filter_input_stream_set_close_base_stream (G_FILTER_INPUT_STREAM (dis), FALSE); g_filter_output_stream_set_close_base_stream (G_FILTER_OUTPUT_STREAM (dos), FALSE); g_data_input_stream_set_newline_type (dis, G_DATA_STREAM_NEWLINE_TYPE_CR_LF); /* first read the NUL-byte (TODO: read credentials if using a unix domain socket) */ #ifdef G_OS_UNIX if (G_IS_UNIX_CONNECTION (auth->priv->stream)) { local_error = NULL; credentials = g_unix_connection_receive_credentials (G_UNIX_CONNECTION (auth->priv->stream), cancellable, &local_error); if (credentials == NULL && !g_error_matches (local_error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED)) { g_propagate_error (error, local_error); goto out; } } else { local_error = NULL; byte = g_data_input_stream_read_byte (dis, cancellable, &local_error); byte = byte; /* To avoid -Wunused-but-set-variable */ if (local_error != NULL) { g_propagate_error (error, local_error); goto out; } } #else local_error = NULL; byte = g_data_input_stream_read_byte (dis, cancellable, &local_error); byte = byte; /* To avoid -Wunused-but-set-variable */ if (local_error != NULL) { g_propagate_error (error, local_error); goto out; } #endif if (credentials != NULL) { if (G_UNLIKELY (_g_dbus_debug_authentication ())) { s = g_credentials_to_string (credentials); debug_print ("SERVER: received credentials `%s'", s); g_free (s); } } else { debug_print ("SERVER: didn't receive any credentials"); } state = SERVER_STATE_WAITING_FOR_AUTH; while (TRUE) { switch (state) { case SERVER_STATE_WAITING_FOR_AUTH: debug_print ("SERVER: WaitingForAuth"); line = _my_g_data_input_stream_read_line (dis, &line_length, cancellable, error); debug_print ("SERVER: WaitingForAuth, read `%s'", line); if (line == NULL) goto out; if (g_strcmp0 (line, "AUTH") == 0) { s = get_auth_mechanisms (auth, allow_anonymous, "REJECTED ", "\r\n", " "); debug_print ("SERVER: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) { g_free (s); goto out; } g_free (s); g_free (line); } else if (g_str_has_prefix (line, "AUTH ")) { gchar **tokens; const gchar *encoded; const gchar *mech_name; GType auth_mech_to_use_gtype; tokens = g_strsplit (line, " ", 0); g_free (line); switch (g_strv_length (tokens)) { case 2: /* no initial response */ mech_name = tokens[1]; encoded = NULL; break; case 3: /* initial response */ mech_name = tokens[1]; encoded = tokens[2]; break; default: g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, "Unexpected line `%s' while in WaitingForAuth state", line); g_strfreev (tokens); goto out; } /* TODO: record that the client has attempted to use this mechanism */ //g_debug ("client is trying `%s'", mech_name); auth_mech_to_use_gtype = find_mech_by_name (auth, mech_name); if ((auth_mech_to_use_gtype == (GType) 0) || (!allow_anonymous && g_strcmp0 (mech_name, "ANONYMOUS") == 0)) { /* We don't support this auth mechanism */ g_strfreev (tokens); s = get_auth_mechanisms (auth, allow_anonymous, "REJECTED ", "\r\n", " "); debug_print ("SERVER: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) { g_free (s); goto out; } g_free (s); /* stay in WAITING FOR AUTH */ state = SERVER_STATE_WAITING_FOR_AUTH; } else { gchar *initial_response; gsize initial_response_len; mech = g_object_new (auth_mech_to_use_gtype, "stream", auth->priv->stream, "credentials", credentials, NULL); initial_response = NULL; initial_response_len = 0; if (encoded != NULL) { initial_response = hexdecode (encoded, &initial_response_len, error); if (initial_response == NULL) { g_prefix_error (error, "Initial response is malformed: "); /* invalid encoding, disconnect! */ g_strfreev (tokens); goto out; } } _g_dbus_auth_mechanism_server_initiate (mech, initial_response, initial_response_len); g_free (initial_response); g_strfreev (tokens); change_state: switch (_g_dbus_auth_mechanism_server_get_state (mech)) { case G_DBUS_AUTH_MECHANISM_STATE_ACCEPTED: if (observer != NULL && !g_dbus_auth_observer_authorize_authenticated_peer (observer, auth->priv->stream, credentials)) { /* disconnect */ g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED, _("Cancelled via GDBusAuthObserver::authorize-authenticated-peer")); goto out; } else { s = g_strdup_printf ("OK %s\r\n", guid); debug_print ("SERVER: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) { g_free (s); goto out; } g_free (s); state = SERVER_STATE_WAITING_FOR_BEGIN; } break; case G_DBUS_AUTH_MECHANISM_STATE_REJECTED: s = get_auth_mechanisms (auth, allow_anonymous, "REJECTED ", "\r\n", " "); debug_print ("SERVER: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) { g_free (s); goto out; } g_free (s); state = SERVER_STATE_WAITING_FOR_AUTH; break; case G_DBUS_AUTH_MECHANISM_STATE_WAITING_FOR_DATA: state = SERVER_STATE_WAITING_FOR_DATA; break; case G_DBUS_AUTH_MECHANISM_STATE_HAVE_DATA_TO_SEND: { gchar *data; gsize data_len; gchar *encoded_data; data = _g_dbus_auth_mechanism_server_data_send (mech, &data_len); encoded_data = hexencode (data); s = g_strdup_printf ("DATA %s\r\n", encoded_data); g_free (encoded_data); g_free (data); debug_print ("SERVER: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) { g_free (s); goto out; } g_free (s); } goto change_state; break; default: /* TODO */ g_assert_not_reached (); break; } } } else { g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, "Unexpected line `%s' while in WaitingForAuth state", line); g_free (line); goto out; } break; case SERVER_STATE_WAITING_FOR_DATA: debug_print ("SERVER: WaitingForData"); line = _my_g_data_input_stream_read_line (dis, &line_length, cancellable, error); debug_print ("SERVER: WaitingForData, read `%s'", line); if (line == NULL) goto out; if (g_str_has_prefix (line, "DATA ")) { gchar *encoded; gchar *decoded_data; gsize decoded_data_len = 0; encoded = g_strdup (line + 5); g_free (line); g_strstrip (encoded); decoded_data = hexdecode (encoded, &decoded_data_len, error); g_free (encoded); if (decoded_data == NULL) { g_prefix_error (error, "DATA response is malformed: "); /* invalid encoding, disconnect! */ goto out; } _g_dbus_auth_mechanism_server_data_receive (mech, decoded_data, decoded_data_len); g_free (decoded_data); /* oh man, this goto-crap is so ugly.. really need to rewrite the state machine */ goto change_state; } else { g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED, "Unexpected line `%s' while in WaitingForData state", line); g_free (line); } goto out; case SERVER_STATE_WAITING_FOR_BEGIN: debug_print ("SERVER: WaitingForBegin"); /* Use extremely slow (but reliable) line reader - this basically * does a recvfrom() system call per character * * (the problem with using GDataInputStream's read_line is that because of * buffering it might start reading into the first D-Bus message that * appears after "BEGIN\r\n"....) */ line = _my_g_input_stream_read_line_safe (g_io_stream_get_input_stream (auth->priv->stream), &line_length, cancellable, error); debug_print ("SERVER: WaitingForBegin, read `%s'", line); if (line == NULL) goto out; if (g_strcmp0 (line, "BEGIN") == 0) { /* YAY, done! */ ret = TRUE; g_free (line); goto out; } else if (g_strcmp0 (line, "NEGOTIATE_UNIX_FD") == 0) { g_free (line); if (offered_capabilities & G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING) { negotiated_capabilities |= G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING; s = "AGREE_UNIX_FD\r\n"; debug_print ("SERVER: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) goto out; } else { s = "ERROR \"fd passing not offered\"\r\n"; debug_print ("SERVER: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) goto out; } } else { g_debug ("Unexpected line `%s' while in WaitingForBegin state", line); g_free (line); s = "ERROR \"Unknown Command\"\r\n"; debug_print ("SERVER: writing `%s'", s); if (!g_data_output_stream_put_string (dos, s, cancellable, error)) goto out; } break; default: g_assert_not_reached (); break; } } g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED, "Not implemented (server)"); out: if (mech != NULL) g_object_unref (mech); if (dis != NULL) g_object_unref (dis); if (dos != NULL) g_object_unref (dos); /* ensure return value is FALSE if error is set */ if (error != NULL && *error != NULL) { ret = FALSE; } if (ret) { if (out_negotiated_capabilities != NULL) *out_negotiated_capabilities = negotiated_capabilities; if (out_received_credentials != NULL) *out_received_credentials = credentials != NULL ? g_object_ref (credentials) : NULL; } if (credentials != NULL) g_object_unref (credentials); debug_print ("SERVER: Done, authenticated=%d", ret); return ret; } /* ---------------------------------------------------------------------------------------------------- */