diff options
Diffstat (limited to 'src/3rdparty/libdbus/dbus/dbus-auth.c')
| -rw-r--r-- | src/3rdparty/libdbus/dbus/dbus-auth.c | 2970 |
1 files changed, 2970 insertions, 0 deletions
diff --git a/src/3rdparty/libdbus/dbus/dbus-auth.c b/src/3rdparty/libdbus/dbus/dbus-auth.c new file mode 100644 index 00000000..09942f80 --- /dev/null +++ b/src/3rdparty/libdbus/dbus/dbus-auth.c @@ -0,0 +1,2970 @@ +/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */ +/* dbus-auth.c Authentication + * + * Copyright (C) 2002, 2003, 2004 Red Hat Inc. + * + * SPDX-License-Identifier: AFL-2.1 OR GPL-2.0-or-later + * + * Licensed under the Academic Free License version 2.1 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + * + */ + +#include <config.h> +#include "dbus-auth.h" +#include "dbus-string.h" +#include "dbus-list.h" +#include "dbus-internals.h" +#include "dbus-keyring.h" +#include "dbus-sha.h" +#include "dbus-protocol.h" +#include "dbus-credentials.h" + +/** + * @defgroup DBusAuth Authentication + * @ingroup DBusInternals + * @brief DBusAuth object + * + * DBusAuth manages the authentication negotiation when a connection + * is first established, and also manages any encryption used over a + * connection. + * + * @todo some SASL profiles require sending the empty string as a + * challenge/response, but we don't currently allow that in our + * protocol. + * + * @todo right now sometimes both ends will block waiting for input + * from the other end, e.g. if there's an error during + * DBUS_COOKIE_SHA1. + * + * @todo the cookie keyring needs to be cached globally not just + * per-auth (which raises threadsafety issues too) + * + * @todo grep FIXME in dbus-auth.c + */ + +/** + * @defgroup DBusAuthInternals Authentication implementation details + * @ingroup DBusInternals + * @brief DBusAuth implementation details + * + * Private details of authentication code. + * + * @{ + */ + +/** + * This function appends an initial client response to the given string + */ +typedef dbus_bool_t (* DBusInitialResponseFunction) (DBusAuth *auth, + DBusString *response); + +/** + * This function processes a block of data received from the peer. + * i.e. handles a DATA command. + */ +typedef dbus_bool_t (* DBusAuthDataFunction) (DBusAuth *auth, + const DBusString *data); + +/** + * This function encodes a block of data from the peer. + */ +typedef dbus_bool_t (* DBusAuthEncodeFunction) (DBusAuth *auth, + const DBusString *data, + DBusString *encoded); + +/** + * This function decodes a block of data from the peer. + */ +typedef dbus_bool_t (* DBusAuthDecodeFunction) (DBusAuth *auth, + const DBusString *data, + DBusString *decoded); + +/** + * This function is called when the mechanism is abandoned. + */ +typedef void (* DBusAuthShutdownFunction) (DBusAuth *auth); + +/** + * Virtual table representing a particular auth mechanism. + */ +typedef struct +{ + const char *mechanism; /**< Name of the mechanism */ + DBusAuthDataFunction server_data_func; /**< Function on server side for DATA */ + DBusAuthEncodeFunction server_encode_func; /**< Function on server side to encode */ + DBusAuthDecodeFunction server_decode_func; /**< Function on server side to decode */ + DBusAuthShutdownFunction server_shutdown_func; /**< Function on server side to shut down */ + DBusInitialResponseFunction client_initial_response_func; /**< Function on client side to handle initial response */ + DBusAuthDataFunction client_data_func; /**< Function on client side for DATA */ + DBusAuthEncodeFunction client_encode_func; /**< Function on client side for encode */ + DBusAuthDecodeFunction client_decode_func; /**< Function on client side for decode */ + DBusAuthShutdownFunction client_shutdown_func; /**< Function on client side for shutdown */ +} DBusAuthMechanismHandler; + +/** + * Enumeration for the known authentication commands. + */ +typedef enum { + DBUS_AUTH_COMMAND_AUTH, + DBUS_AUTH_COMMAND_CANCEL, + DBUS_AUTH_COMMAND_DATA, + DBUS_AUTH_COMMAND_BEGIN, + DBUS_AUTH_COMMAND_REJECTED, + DBUS_AUTH_COMMAND_OK, + DBUS_AUTH_COMMAND_ERROR, + DBUS_AUTH_COMMAND_UNKNOWN, + DBUS_AUTH_COMMAND_NEGOTIATE_UNIX_FD, + DBUS_AUTH_COMMAND_AGREE_UNIX_FD +} DBusAuthCommand; + +/** + * Auth state function, determines the reaction to incoming events for + * a particular state. Returns whether we had enough memory to + * complete the operation. + */ +typedef dbus_bool_t (* DBusAuthStateFunction) (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args); + +/** + * Information about a auth state. + */ +typedef struct +{ + const char *name; /**< Name of the state */ + DBusAuthStateFunction handler; /**< State function for this state */ +} DBusAuthStateData; + +/** + * Internal members of DBusAuth. + */ +struct DBusAuth +{ + int refcount; /**< reference count */ + const char *side; /**< Client or server */ + + DBusString incoming; /**< Incoming data buffer */ + DBusString outgoing; /**< Outgoing data buffer */ + + const DBusAuthStateData *state; /**< Current protocol state */ + + const DBusAuthMechanismHandler *mech; /**< Current auth mechanism */ + + DBusString identity; /**< Current identity we're authorizing + * as. + */ + + DBusCredentials *credentials; /**< Credentials read from socket + */ + + DBusCredentials *authorized_identity; /**< Credentials that are authorized */ + + DBusCredentials *desired_identity; /**< Identity client has requested */ + + DBusString context; /**< Cookie scope */ + DBusKeyring *keyring; /**< Keyring for cookie mechanism. */ + int cookie_id; /**< ID of cookie to use */ + DBusString challenge; /**< Challenge sent to client */ + + char **allowed_mechs; /**< Mechanisms we're allowed to use, + * or #NULL if we can use any + */ + + unsigned int needed_memory : 1; /**< We needed memory to continue since last + * successful getting something done + */ + unsigned int already_got_mechanisms : 1; /**< Client already got mech list */ + unsigned int already_asked_for_initial_response : 1; /**< Already sent a blank challenge to get an initial response */ + unsigned int buffer_outstanding : 1; /**< Buffer is "checked out" for reading data into */ + + unsigned int unix_fd_possible : 1; /**< This side could do unix fd passing */ + unsigned int unix_fd_negotiated : 1; /**< Unix fd was successfully negotiated */ +}; + +/** + * "Subclass" of DBusAuth for client side + */ +typedef struct +{ + DBusAuth base; /**< Parent class */ + + DBusList *mechs_to_try; /**< Mechanisms we got from the server that we're going to try using */ + + DBusString guid_from_server; /**< GUID received from server */ + +} DBusAuthClient; + +/** + * "Subclass" of DBusAuth for server side. + */ +typedef struct +{ + DBusAuth base; /**< Parent class */ + + int failures; /**< Number of times client has been rejected */ + int max_failures; /**< Number of times we reject before disconnect */ + + DBusString guid; /**< Our globally unique ID in hex encoding */ + +} DBusAuthServer; + +static void goto_state (DBusAuth *auth, + const DBusAuthStateData *new_state); +static dbus_bool_t send_auth (DBusAuth *auth, + const DBusAuthMechanismHandler *mech); +static dbus_bool_t send_data (DBusAuth *auth, + DBusString *data); +static dbus_bool_t send_rejected (DBusAuth *auth); +static dbus_bool_t send_error (DBusAuth *auth, + const char *message); +static dbus_bool_t send_ok (DBusAuth *auth); +static dbus_bool_t send_begin (DBusAuth *auth); +static dbus_bool_t send_cancel (DBusAuth *auth); +static dbus_bool_t send_negotiate_unix_fd (DBusAuth *auth); +static dbus_bool_t send_agree_unix_fd (DBusAuth *auth); + +/** + * Client states + */ + +static dbus_bool_t handle_server_state_waiting_for_auth (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args); +static dbus_bool_t handle_server_state_waiting_for_data (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args); +static dbus_bool_t handle_server_state_waiting_for_begin (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args); + +static const DBusAuthStateData server_state_waiting_for_auth = { + "WaitingForAuth", handle_server_state_waiting_for_auth +}; +static const DBusAuthStateData server_state_waiting_for_data = { + "WaitingForData", handle_server_state_waiting_for_data +}; +static const DBusAuthStateData server_state_waiting_for_begin = { + "WaitingForBegin", handle_server_state_waiting_for_begin +}; + +/** + * Client states + */ + +static dbus_bool_t handle_client_state_waiting_for_data (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args); +static dbus_bool_t handle_client_state_waiting_for_ok (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args); +static dbus_bool_t handle_client_state_waiting_for_reject (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args); +static dbus_bool_t handle_client_state_waiting_for_agree_unix_fd (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args); + +static const DBusAuthStateData client_state_need_send_auth = { + "NeedSendAuth", NULL +}; +static const DBusAuthStateData client_state_waiting_for_data = { + "WaitingForData", handle_client_state_waiting_for_data +}; +/* The WaitingForOK state doesn't appear to be used. + * See https://bugs.freedesktop.org/show_bug.cgi?id=97298 */ +_DBUS_GNUC_UNUSED +static const DBusAuthStateData client_state_waiting_for_ok = { + "WaitingForOK", handle_client_state_waiting_for_ok +}; +static const DBusAuthStateData client_state_waiting_for_reject = { + "WaitingForReject", handle_client_state_waiting_for_reject +}; +static const DBusAuthStateData client_state_waiting_for_agree_unix_fd = { + "WaitingForAgreeUnixFD", handle_client_state_waiting_for_agree_unix_fd +}; + +/** + * Common terminal states. Terminal states have handler == NULL. + */ + +static const DBusAuthStateData common_state_authenticated = { + "Authenticated", NULL +}; + +static const DBusAuthStateData common_state_need_disconnect = { + "NeedDisconnect", NULL +}; + +static const char auth_side_client[] = "client"; +static const char auth_side_server[] = "server"; +/** + * @param auth the auth conversation + * @returns #TRUE if the conversation is the server side + */ +#define DBUS_AUTH_IS_SERVER(auth) ((auth)->side == auth_side_server) +/** + * @param auth the auth conversation + * @returns #TRUE if the conversation is the client side + */ +#define DBUS_AUTH_IS_CLIENT(auth) ((auth)->side == auth_side_client) +/** + * @param auth the auth conversation + * @returns auth cast to DBusAuthClient + */ +#define DBUS_AUTH_CLIENT(auth) ((DBusAuthClient*)(auth)) +/** + * @param auth the auth conversation + * @returns auth cast to DBusAuthServer + */ +#define DBUS_AUTH_SERVER(auth) ((DBusAuthServer*)(auth)) + +/** + * The name of the auth ("client" or "server") + * @param auth the auth conversation + * @returns a string + */ +#define DBUS_AUTH_NAME(auth) ((auth)->side) + +static DBusAuth* +_dbus_auth_new (int size) +{ + DBusAuth *auth; + + auth = dbus_malloc0 (size); + if (auth == NULL) + return NULL; + + auth->refcount = 1; + + auth->keyring = NULL; + auth->cookie_id = -1; + + /* note that we don't use the max string length feature, + * because you can't use that feature if you're going to + * try to recover from out-of-memory (it creates + * what looks like unrecoverable inability to alloc + * more space in the string). But we do handle + * overlong buffers in _dbus_auth_do_work(). + */ + + if (!_dbus_string_init (&auth->incoming)) + goto enomem_0; + + if (!_dbus_string_init (&auth->outgoing)) + goto enomem_1; + + if (!_dbus_string_init (&auth->identity)) + goto enomem_2; + + if (!_dbus_string_init (&auth->context)) + goto enomem_3; + + if (!_dbus_string_init (&auth->challenge)) + goto enomem_4; + + /* default context if none is specified */ + if (!_dbus_string_append (&auth->context, "org_freedesktop_general")) + goto enomem_5; + + auth->credentials = _dbus_credentials_new (); + if (auth->credentials == NULL) + goto enomem_6; + + auth->authorized_identity = _dbus_credentials_new (); + if (auth->authorized_identity == NULL) + goto enomem_7; + + auth->desired_identity = _dbus_credentials_new (); + if (auth->desired_identity == NULL) + goto enomem_8; + + return auth; + +#if 0 + enomem_9: + _dbus_credentials_unref (auth->desired_identity); +#endif + enomem_8: + _dbus_credentials_unref (auth->authorized_identity); + enomem_7: + _dbus_credentials_unref (auth->credentials); + enomem_6: + /* last alloc was an append to context, which is freed already below */ ; + enomem_5: + _dbus_string_free (&auth->challenge); + enomem_4: + _dbus_string_free (&auth->context); + enomem_3: + _dbus_string_free (&auth->identity); + enomem_2: + _dbus_string_free (&auth->outgoing); + enomem_1: + _dbus_string_free (&auth->incoming); + enomem_0: + dbus_free (auth); + return NULL; +} + +static void +shutdown_mech (DBusAuth *auth) +{ + /* Cancel any auth */ + auth->already_asked_for_initial_response = FALSE; + _dbus_string_set_length (&auth->identity, 0); + + _dbus_credentials_clear (auth->authorized_identity); + _dbus_credentials_clear (auth->desired_identity); + + if (auth->mech != NULL) + { + _dbus_verbose ("%s: Shutting down mechanism %s\n", + DBUS_AUTH_NAME (auth), auth->mech->mechanism); + + if (DBUS_AUTH_IS_CLIENT (auth)) + (* auth->mech->client_shutdown_func) (auth); + else + (* auth->mech->server_shutdown_func) (auth); + + auth->mech = NULL; + } +} + +/* + * DBUS_COOKIE_SHA1 mechanism + */ + +/* Returns TRUE but with an empty string hash if the + * cookie_id isn't known. As with all this code + * TRUE just means we had enough memory. + */ +static dbus_bool_t +sha1_compute_hash (DBusAuth *auth, + int cookie_id, + const DBusString *server_challenge, + const DBusString *client_challenge, + DBusString *hash) +{ + DBusString cookie; + DBusString to_hash; + dbus_bool_t retval; + + _dbus_assert (auth->keyring != NULL); + + retval = FALSE; + + if (!_dbus_string_init (&cookie)) + return FALSE; + + if (!_dbus_keyring_get_hex_key (auth->keyring, cookie_id, + &cookie)) + goto out_0; + + if (_dbus_string_get_length (&cookie) == 0) + { + retval = TRUE; + goto out_0; + } + + if (!_dbus_string_init (&to_hash)) + goto out_0; + + if (!_dbus_string_copy (server_challenge, 0, + &to_hash, _dbus_string_get_length (&to_hash))) + goto out_1; + + if (!_dbus_string_append (&to_hash, ":")) + goto out_1; + + if (!_dbus_string_copy (client_challenge, 0, + &to_hash, _dbus_string_get_length (&to_hash))) + goto out_1; + + if (!_dbus_string_append (&to_hash, ":")) + goto out_1; + + if (!_dbus_string_copy (&cookie, 0, + &to_hash, _dbus_string_get_length (&to_hash))) + goto out_1; + + if (!_dbus_sha_compute (&to_hash, hash)) + goto out_1; + + retval = TRUE; + + out_1: + _dbus_string_zero (&to_hash); + _dbus_string_free (&to_hash); + out_0: + _dbus_string_zero (&cookie); + _dbus_string_free (&cookie); + return retval; +} + +/** http://www.ietf.org/rfc/rfc2831.txt suggests at least 64 bits of + * entropy, we use 128. This is the number of bytes in the random + * challenge. + */ +#define N_CHALLENGE_BYTES (128/8) + +static dbus_bool_t +sha1_handle_first_client_response (DBusAuth *auth, + const DBusString *data) +{ + /* We haven't sent a challenge yet, we're expecting a desired + * username from the client. + */ + DBusString tmp = _DBUS_STRING_INIT_INVALID; + DBusString tmp2 = _DBUS_STRING_INIT_INVALID; + dbus_bool_t retval = FALSE; + DBusError error = DBUS_ERROR_INIT; + DBusCredentials *myself = NULL; + + _dbus_string_set_length (&auth->challenge, 0); + + if (_dbus_string_get_length (data) > 0) + { + if (_dbus_string_get_length (&auth->identity) > 0) + { + /* Tried to send two auth identities, wtf */ + _dbus_verbose ("%s: client tried to send auth identity, but we already have one\n", + DBUS_AUTH_NAME (auth)); + return send_rejected (auth); + } + else + { + /* this is our auth identity */ + if (!_dbus_string_copy (data, 0, &auth->identity, 0)) + return FALSE; + } + } + + if (!_dbus_credentials_add_from_user (auth->desired_identity, data, + DBUS_CREDENTIALS_ADD_FLAGS_USER_DATABASE, + &error)) + { + if (dbus_error_has_name (&error, DBUS_ERROR_NO_MEMORY)) + { + dbus_error_free (&error); + return FALSE; + } + + _dbus_verbose ("%s: Did not get a valid username from client: %s\n", + DBUS_AUTH_NAME (auth), error.message); + dbus_error_free (&error); + return send_rejected (auth); + } + + if (!_dbus_string_init (&tmp)) + return FALSE; + + if (!_dbus_string_init (&tmp2)) + { + _dbus_string_free (&tmp); + return FALSE; + } + + myself = _dbus_credentials_new_from_current_process (); + + if (myself == NULL) + goto out; + + if (!_dbus_credentials_same_user (myself, auth->desired_identity)) + { + /* + * DBUS_COOKIE_SHA1 is not suitable for authenticating that the + * client is anyone other than the user owning the process + * containing the DBusServer: we probably aren't allowed to write + * to other users' home directories. Even if we can (for example + * uid 0 on traditional Unix or CAP_DAC_OVERRIDE on Linux), we + * must not, because the other user controls their home directory, + * and could carry out symlink attacks to make us read from or + * write to unintended locations. It's difficult to avoid symlink + * attacks in a portable way, so we just don't try. This isn't a + * regression, because DBUS_COOKIE_SHA1 never worked for other + * users anyway. + */ + _dbus_verbose ("%s: client tried to authenticate as \"%s\", " + "but that doesn't match this process", + DBUS_AUTH_NAME (auth), + _dbus_string_get_const_data (data)); + retval = send_rejected (auth); + goto out; + } + + /* we cache the keyring for speed, so here we drop it if it's the + * wrong one. FIXME caching the keyring here is useless since we use + * a different DBusAuth for every connection. + */ + if (auth->keyring && + !_dbus_keyring_is_for_credentials (auth->keyring, + auth->desired_identity)) + { + _dbus_keyring_unref (auth->keyring); + auth->keyring = NULL; + } + + if (auth->keyring == NULL) + { + auth->keyring = _dbus_keyring_new_for_credentials (auth->desired_identity, + &auth->context, + &error); + + if (auth->keyring == NULL) + { + if (dbus_error_has_name (&error, + DBUS_ERROR_NO_MEMORY)) + { + dbus_error_free (&error); + goto out; + } + else + { + _DBUS_ASSERT_ERROR_IS_SET (&error); + _dbus_verbose ("%s: Error loading keyring: %s\n", + DBUS_AUTH_NAME (auth), error.message); + if (send_rejected (auth)) + retval = TRUE; /* retval is only about mem */ + dbus_error_free (&error); + goto out; + } + } + else + { + _dbus_assert (!dbus_error_is_set (&error)); + } + } + + _dbus_assert (auth->keyring != NULL); + + auth->cookie_id = _dbus_keyring_get_best_key (auth->keyring, &error); + if (auth->cookie_id < 0) + { + _DBUS_ASSERT_ERROR_IS_SET (&error); + _dbus_verbose ("%s: Could not get a cookie ID to send to client: %s\n", + DBUS_AUTH_NAME (auth), error.message); + if (send_rejected (auth)) + retval = TRUE; + dbus_error_free (&error); + goto out; + } + else + { + _dbus_assert (!dbus_error_is_set (&error)); + } + + if (!_dbus_string_copy (&auth->context, 0, + &tmp2, _dbus_string_get_length (&tmp2))) + goto out; + + if (!_dbus_string_append (&tmp2, " ")) + goto out; + + if (!_dbus_string_append_int (&tmp2, auth->cookie_id)) + goto out; + + if (!_dbus_string_append (&tmp2, " ")) + goto out; + + if (!_dbus_generate_random_bytes (&tmp, N_CHALLENGE_BYTES, &error)) + { + if (dbus_error_has_name (&error, DBUS_ERROR_NO_MEMORY)) + { + dbus_error_free (&error); + goto out; + } + else + { + _DBUS_ASSERT_ERROR_IS_SET (&error); + _dbus_verbose ("%s: Error generating challenge: %s\n", + DBUS_AUTH_NAME (auth), error.message); + if (send_rejected (auth)) + retval = TRUE; /* retval is only about mem */ + + dbus_error_free (&error); + goto out; + } + } + + _dbus_string_set_length (&auth->challenge, 0); + if (!_dbus_string_hex_encode (&tmp, 0, &auth->challenge, 0)) + goto out; + + if (!_dbus_string_hex_encode (&tmp, 0, &tmp2, + _dbus_string_get_length (&tmp2))) + goto out; + + if (!send_data (auth, &tmp2)) + goto out; + + goto_state (auth, &server_state_waiting_for_data); + retval = TRUE; + + out: + _dbus_string_zero (&tmp); + _dbus_string_free (&tmp); + _dbus_string_zero (&tmp2); + _dbus_string_free (&tmp2); + _dbus_clear_credentials (&myself); + + return retval; +} + +static dbus_bool_t +sha1_handle_second_client_response (DBusAuth *auth, + const DBusString *data) +{ + /* We are expecting a response which is the hex-encoded client + * challenge, space, then SHA-1 hash of the concatenation of our + * challenge, ":", client challenge, ":", secret key, all + * hex-encoded. + */ + int i; + DBusString client_challenge; + DBusString client_hash; + dbus_bool_t retval; + DBusString correct_hash; + + retval = FALSE; + + if (!_dbus_string_find_blank (data, 0, &i)) + { + _dbus_verbose ("%s: no space separator in client response\n", + DBUS_AUTH_NAME (auth)); + return send_rejected (auth); + } + + if (!_dbus_string_init (&client_challenge)) + goto out_0; + + if (!_dbus_string_init (&client_hash)) + goto out_1; + + if (!_dbus_string_copy_len (data, 0, i, &client_challenge, + 0)) + goto out_2; + + _dbus_string_skip_blank (data, i, &i); + + if (!_dbus_string_copy_len (data, i, + _dbus_string_get_length (data) - i, + &client_hash, + 0)) + goto out_2; + + if (_dbus_string_get_length (&client_challenge) == 0 || + _dbus_string_get_length (&client_hash) == 0) + { + _dbus_verbose ("%s: zero-length client challenge or hash\n", + DBUS_AUTH_NAME (auth)); + if (send_rejected (auth)) + retval = TRUE; + goto out_2; + } + + if (!_dbus_string_init (&correct_hash)) + goto out_2; + + if (!sha1_compute_hash (auth, auth->cookie_id, + &auth->challenge, + &client_challenge, + &correct_hash)) + goto out_3; + + /* if cookie_id was invalid, then we get an empty hash */ + if (_dbus_string_get_length (&correct_hash) == 0) + { + if (send_rejected (auth)) + retval = TRUE; + goto out_3; + } + + if (!_dbus_string_equal (&client_hash, &correct_hash)) + { + if (send_rejected (auth)) + retval = TRUE; + goto out_3; + } + + if (!_dbus_credentials_add_credentials (auth->authorized_identity, + auth->desired_identity)) + goto out_3; + + /* Copy process ID (and PID FD) from the socket credentials if it's there + */ + if (!_dbus_credentials_add_credential (auth->authorized_identity, + DBUS_CREDENTIAL_UNIX_PROCESS_FD, + auth->credentials)) + goto out_3; + if (!_dbus_credentials_add_credential (auth->authorized_identity, + DBUS_CREDENTIAL_UNIX_PROCESS_ID, + auth->credentials)) + goto out_3; + + if (!send_ok (auth)) + goto out_3; + + _dbus_verbose ("%s: authenticated client using DBUS_COOKIE_SHA1\n", + DBUS_AUTH_NAME (auth)); + + retval = TRUE; + + out_3: + _dbus_string_zero (&correct_hash); + _dbus_string_free (&correct_hash); + out_2: + _dbus_string_zero (&client_hash); + _dbus_string_free (&client_hash); + out_1: + _dbus_string_free (&client_challenge); + out_0: + return retval; +} + +static dbus_bool_t +handle_server_data_cookie_sha1_mech (DBusAuth *auth, + const DBusString *data) +{ + if (auth->cookie_id < 0) + return sha1_handle_first_client_response (auth, data); + else + return sha1_handle_second_client_response (auth, data); +} + +static void +handle_server_shutdown_cookie_sha1_mech (DBusAuth *auth) +{ + auth->cookie_id = -1; + _dbus_string_set_length (&auth->challenge, 0); +} + +static dbus_bool_t +handle_client_initial_response_cookie_sha1_mech (DBusAuth *auth, + DBusString *response) +{ + DBusString username; + dbus_bool_t retval; + + retval = FALSE; + + if (!_dbus_string_init (&username)) + return FALSE; + + if (!_dbus_append_user_from_current_process (&username)) + goto out_0; + + if (!_dbus_string_hex_encode (&username, 0, + response, + _dbus_string_get_length (response))) + goto out_0; + + retval = TRUE; + + out_0: + _dbus_string_free (&username); + + return retval; +} + +static dbus_bool_t +handle_client_data_cookie_sha1_mech (DBusAuth *auth, + const DBusString *data) +{ + /* The data we get from the server should be the cookie context + * name, the cookie ID, and the server challenge, separated by + * spaces. We send back our challenge string and the correct hash. + */ + dbus_bool_t retval = FALSE; + DBusString context; + DBusString cookie_id_str; + DBusString server_challenge; + DBusString client_challenge; + DBusString correct_hash; + DBusString tmp; + int i, j; + long val; + DBusError error = DBUS_ERROR_INIT; + + if (!_dbus_string_find_blank (data, 0, &i)) + { + if (send_error (auth, + "Server did not send context/ID/challenge properly")) + retval = TRUE; + goto out_0; + } + + if (!_dbus_string_init (&context)) + goto out_0; + + if (!_dbus_string_copy_len (data, 0, i, + &context, 0)) + goto out_1; + + _dbus_string_skip_blank (data, i, &i); + if (!_dbus_string_find_blank (data, i, &j)) + { + if (send_error (auth, + "Server did not send context/ID/challenge properly")) + retval = TRUE; + goto out_1; + } + + if (!_dbus_string_init (&cookie_id_str)) + goto out_1; + + if (!_dbus_string_copy_len (data, i, j - i, + &cookie_id_str, 0)) + goto out_2; + + if (!_dbus_string_init (&server_challenge)) + goto out_2; + + i = j; + _dbus_string_skip_blank (data, i, &i); + j = _dbus_string_get_length (data); + + if (!_dbus_string_copy_len (data, i, j - i, + &server_challenge, 0)) + goto out_3; + + if (!_dbus_keyring_validate_context (&context)) + { + if (send_error (auth, "Server sent invalid cookie context")) + retval = TRUE; + goto out_3; + } + + if (!_dbus_string_parse_int (&cookie_id_str, 0, &val, NULL)) + { + if (send_error (auth, "Could not parse cookie ID as an integer")) + retval = TRUE; + goto out_3; + } + + if (_dbus_string_get_length (&server_challenge) == 0) + { + if (send_error (auth, "Empty server challenge string")) + retval = TRUE; + goto out_3; + } + + if (auth->keyring == NULL) + { + auth->keyring = _dbus_keyring_new_for_credentials (NULL, + &context, + &error); + + if (auth->keyring == NULL) + { + if (dbus_error_has_name (&error, + DBUS_ERROR_NO_MEMORY)) + { + dbus_error_free (&error); + goto out_3; + } + else + { + _DBUS_ASSERT_ERROR_IS_SET (&error); + + _dbus_verbose ("%s: Error loading keyring: %s\n", + DBUS_AUTH_NAME (auth), error.message); + + if (send_error (auth, "Could not load cookie file")) + retval = TRUE; /* retval is only about mem */ + + dbus_error_free (&error); + goto out_3; + } + } + else + { + _dbus_assert (!dbus_error_is_set (&error)); + } + } + + _dbus_assert (auth->keyring != NULL); + + if (!_dbus_string_init (&tmp)) + goto out_3; + + if (!_dbus_generate_random_bytes (&tmp, N_CHALLENGE_BYTES, &error)) + { + if (dbus_error_has_name (&error, DBUS_ERROR_NO_MEMORY)) + { + dbus_error_free (&error); + goto out_4; + } + else + { + _DBUS_ASSERT_ERROR_IS_SET (&error); + + _dbus_verbose ("%s: Failed to generate challenge: %s\n", + DBUS_AUTH_NAME (auth), error.message); + + if (send_error (auth, "Failed to generate challenge")) + retval = TRUE; /* retval is only about mem */ + + dbus_error_free (&error); + goto out_4; + } + } + + if (!_dbus_string_init (&client_challenge)) + goto out_4; + + if (!_dbus_string_hex_encode (&tmp, 0, &client_challenge, 0)) + goto out_5; + + if (!_dbus_string_init (&correct_hash)) + goto out_5; + + if (!sha1_compute_hash (auth, val, + &server_challenge, + &client_challenge, + &correct_hash)) + goto out_6; + + if (_dbus_string_get_length (&correct_hash) == 0) + { + /* couldn't find the cookie ID or something */ + if (send_error (auth, "Don't have the requested cookie ID")) + retval = TRUE; + goto out_6; + } + + _dbus_string_set_length (&tmp, 0); + + if (!_dbus_string_copy (&client_challenge, 0, &tmp, + _dbus_string_get_length (&tmp))) + goto out_6; + + if (!_dbus_string_append (&tmp, " ")) + goto out_6; + + if (!_dbus_string_copy (&correct_hash, 0, &tmp, + _dbus_string_get_length (&tmp))) + goto out_6; + + if (!send_data (auth, &tmp)) + goto out_6; + + retval = TRUE; + + out_6: + _dbus_string_zero (&correct_hash); + _dbus_string_free (&correct_hash); + out_5: + _dbus_string_free (&client_challenge); + out_4: + _dbus_string_zero (&tmp); + _dbus_string_free (&tmp); + out_3: + _dbus_string_free (&server_challenge); + out_2: + _dbus_string_free (&cookie_id_str); + out_1: + _dbus_string_free (&context); + out_0: + return retval; +} + +static void +handle_client_shutdown_cookie_sha1_mech (DBusAuth *auth) +{ + auth->cookie_id = -1; + _dbus_string_set_length (&auth->challenge, 0); +} + +/* + * EXTERNAL mechanism + */ + +static dbus_bool_t +handle_server_data_external_mech (DBusAuth *auth, + const DBusString *data) +{ + if (_dbus_credentials_are_anonymous (auth->credentials)) + { + _dbus_verbose ("%s: no credentials, mechanism EXTERNAL can't authenticate\n", + DBUS_AUTH_NAME (auth)); + return send_rejected (auth); + } + + if (_dbus_string_get_length (data) > 0) + { + if (_dbus_string_get_length (&auth->identity) > 0) + { + /* Tried to send two auth identities, wtf */ + _dbus_verbose ("%s: client tried to send auth identity, but we already have one\n", + DBUS_AUTH_NAME (auth)); + return send_rejected (auth); + } + else + { + /* this is our auth identity */ + if (!_dbus_string_copy (data, 0, &auth->identity, 0)) + return FALSE; + } + } + + /* Poke client for an auth identity, if none given */ + if (_dbus_string_get_length (&auth->identity) == 0 && + !auth->already_asked_for_initial_response) + { + if (send_data (auth, NULL)) + { + _dbus_verbose ("%s: sending empty challenge asking client for auth identity\n", + DBUS_AUTH_NAME (auth)); + auth->already_asked_for_initial_response = TRUE; + goto_state (auth, &server_state_waiting_for_data); + return TRUE; + } + else + return FALSE; + } + + _dbus_credentials_clear (auth->desired_identity); + + /* If auth->identity is still empty here, then client + * responded with an empty string after we poked it for + * an initial response. This means to try to auth the + * identity provided in the credentials. + */ + if (_dbus_string_get_length (&auth->identity) == 0) + { + if (!_dbus_credentials_add_credentials (auth->desired_identity, + auth->credentials)) + { + return FALSE; /* OOM */ + } + } + else + { + DBusError error = DBUS_ERROR_INIT; + + if (!_dbus_credentials_add_from_user (auth->desired_identity, + &auth->identity, + DBUS_CREDENTIALS_ADD_FLAGS_NONE, + &error)) + { + if (dbus_error_has_name (&error, DBUS_ERROR_NO_MEMORY)) + { + dbus_error_free (&error); + return FALSE; + } + + _dbus_verbose ("%s: could not get credentials from uid string: %s\n", + DBUS_AUTH_NAME (auth), error.message); + dbus_error_free (&error); + return send_rejected (auth); + } + } + + if (_dbus_credentials_are_anonymous (auth->desired_identity)) + { + _dbus_verbose ("%s: desired user %s is no good\n", + DBUS_AUTH_NAME (auth), + _dbus_string_get_const_data (&auth->identity)); + return send_rejected (auth); + } + + if (_dbus_credentials_are_superset (auth->credentials, + auth->desired_identity)) + { + /* client has authenticated */ + if (!_dbus_credentials_add_credentials (auth->authorized_identity, + auth->desired_identity)) + return FALSE; + + /* also copy misc process info from the socket credentials + */ + if (!_dbus_credentials_add_credential (auth->authorized_identity, + DBUS_CREDENTIAL_UNIX_PROCESS_FD, + auth->credentials)) + return FALSE; + + if (!_dbus_credentials_add_credential (auth->authorized_identity, + DBUS_CREDENTIAL_UNIX_PROCESS_ID, + auth->credentials)) + return FALSE; + + if (!_dbus_credentials_add_credential (auth->authorized_identity, + DBUS_CREDENTIAL_ADT_AUDIT_DATA_ID, + auth->credentials)) + return FALSE; + + if (!_dbus_credentials_add_credential (auth->authorized_identity, + DBUS_CREDENTIAL_UNIX_GROUP_IDS, + auth->credentials)) + return FALSE; + + if (!_dbus_credentials_add_credential (auth->authorized_identity, + DBUS_CREDENTIAL_LINUX_SECURITY_LABEL, + auth->credentials)) + return FALSE; + + if (!send_ok (auth)) + return FALSE; + + _dbus_verbose ("%s: authenticated client based on socket credentials\n", + DBUS_AUTH_NAME (auth)); + + return TRUE; + } + else + { + _dbus_verbose ("%s: desired identity not found in socket credentials\n", + DBUS_AUTH_NAME (auth)); + return send_rejected (auth); + } +} + +static void +handle_server_shutdown_external_mech (DBusAuth *auth) +{ + +} + +static dbus_bool_t +handle_client_initial_response_external_mech (DBusAuth *auth, + DBusString *response) +{ + /* We always append our UID as an initial response, so the server + * doesn't have to send back an empty challenge to check whether we + * want to specify an identity. i.e. this avoids a round trip that + * the spec for the EXTERNAL mechanism otherwise requires. + */ + DBusString plaintext; + + if (!_dbus_string_init (&plaintext)) + return FALSE; + + if (!_dbus_append_user_from_current_process (&plaintext)) + goto failed; + + if (!_dbus_string_hex_encode (&plaintext, 0, + response, + _dbus_string_get_length (response))) + goto failed; + + _dbus_string_free (&plaintext); + + return TRUE; + + failed: + _dbus_string_free (&plaintext); + return FALSE; +} + +static dbus_bool_t +handle_client_data_external_mech (DBusAuth *auth, + const DBusString *data) +{ + + return TRUE; +} + +static void +handle_client_shutdown_external_mech (DBusAuth *auth) +{ + +} + +/* + * ANONYMOUS mechanism + */ + +static dbus_bool_t +handle_server_data_anonymous_mech (DBusAuth *auth, + const DBusString *data) +{ + if (_dbus_string_get_length (data) > 0) + { + /* Client is allowed to send "trace" data, the only defined + * meaning is that if it contains '@' it is an email address, + * and otherwise it is anything else, and it's supposed to be + * UTF-8 + */ + if (!_dbus_string_validate_utf8 (data, 0, _dbus_string_get_length (data))) + { + _dbus_verbose ("%s: Received invalid UTF-8 trace data from ANONYMOUS client\n", + DBUS_AUTH_NAME (auth)); + return send_rejected (auth); + } + + _dbus_verbose ("%s: ANONYMOUS client sent trace string: '%s'\n", + DBUS_AUTH_NAME (auth), + _dbus_string_get_const_data (data)); + } + + /* We want to be anonymous (clear in case some other protocol got midway through I guess) */ + _dbus_credentials_clear (auth->desired_identity); + + /* Copy process ID (and PID FD) from the socket credentials + */ + if (!_dbus_credentials_add_credential (auth->authorized_identity, + DBUS_CREDENTIAL_UNIX_PROCESS_FD, + auth->credentials)) + return FALSE; + + if (!_dbus_credentials_add_credential (auth->authorized_identity, + DBUS_CREDENTIAL_UNIX_PROCESS_ID, + auth->credentials)) + return FALSE; + + /* Anonymous is always allowed */ + if (!send_ok (auth)) + return FALSE; + + _dbus_verbose ("%s: authenticated client as anonymous\n", + DBUS_AUTH_NAME (auth)); + + return TRUE; +} + +static void +handle_server_shutdown_anonymous_mech (DBusAuth *auth) +{ + +} + +static dbus_bool_t +handle_client_initial_response_anonymous_mech (DBusAuth *auth, + DBusString *response) +{ + /* Our initial response is a "trace" string which must be valid UTF-8 + * and must be an email address if it contains '@'. + * We just send the dbus implementation info, like a user-agent or + * something, because... why not. There's nothing guaranteed here + * though, we could change it later. + */ + DBusString plaintext; + + if (!_dbus_string_init (&plaintext)) + return FALSE; + + if (!_dbus_string_append (&plaintext, + "libdbus " DBUS_VERSION_STRING)) + goto failed; + + if (!_dbus_string_hex_encode (&plaintext, 0, + response, + _dbus_string_get_length (response))) + goto failed; + + _dbus_string_free (&plaintext); + + return TRUE; + + failed: + _dbus_string_free (&plaintext); + return FALSE; +} + +static dbus_bool_t +handle_client_data_anonymous_mech (DBusAuth *auth, + const DBusString *data) +{ + + return TRUE; +} + +static void +handle_client_shutdown_anonymous_mech (DBusAuth *auth) +{ + +} + +/* Put mechanisms here in order of preference. + * Right now we have: + * + * - EXTERNAL checks socket credentials (or in the future, other info from the OS) + * - DBUS_COOKIE_SHA1 uses a cookie in the home directory, like xauth or ICE + * - ANONYMOUS checks nothing but doesn't auth the person as a user + * + * We might ideally add a mechanism to chain to Cyrus SASL so we can + * use its mechanisms as well. + * + */ +static const DBusAuthMechanismHandler +all_mechanisms[] = { + { "EXTERNAL", + handle_server_data_external_mech, + NULL, NULL, + handle_server_shutdown_external_mech, + handle_client_initial_response_external_mech, + handle_client_data_external_mech, + NULL, NULL, + handle_client_shutdown_external_mech }, + { "DBUS_COOKIE_SHA1", + handle_server_data_cookie_sha1_mech, + NULL, NULL, + handle_server_shutdown_cookie_sha1_mech, + handle_client_initial_response_cookie_sha1_mech, + handle_client_data_cookie_sha1_mech, + NULL, NULL, + handle_client_shutdown_cookie_sha1_mech }, + { "ANONYMOUS", + handle_server_data_anonymous_mech, + NULL, NULL, + handle_server_shutdown_anonymous_mech, + handle_client_initial_response_anonymous_mech, + handle_client_data_anonymous_mech, + NULL, NULL, + handle_client_shutdown_anonymous_mech }, + { NULL, NULL } +}; + +static const DBusAuthMechanismHandler* +find_mech (const DBusString *name, + char **allowed_mechs) +{ + int i; + + if (allowed_mechs != NULL && + !_dbus_string_array_contains ((const char**) allowed_mechs, + _dbus_string_get_const_data (name))) + return NULL; + + i = 0; + while (all_mechanisms[i].mechanism != NULL) + { + if (_dbus_string_equal_c_str (name, + all_mechanisms[i].mechanism)) + + return &all_mechanisms[i]; + + ++i; + } + + return NULL; +} + +static dbus_bool_t +send_auth (DBusAuth *auth, const DBusAuthMechanismHandler *mech) +{ + DBusString auth_command; + + if (!_dbus_string_init (&auth_command)) + return FALSE; + + if (!_dbus_string_append (&auth_command, + "AUTH ")) + { + _dbus_string_free (&auth_command); + return FALSE; + } + + if (!_dbus_string_append (&auth_command, + mech->mechanism)) + { + _dbus_string_free (&auth_command); + return FALSE; + } + + if (mech->client_initial_response_func != NULL) + { + if (!_dbus_string_append (&auth_command, " ")) + { + _dbus_string_free (&auth_command); + return FALSE; + } + + if (!(* mech->client_initial_response_func) (auth, &auth_command)) + { + _dbus_string_free (&auth_command); + return FALSE; + } + } + + if (!_dbus_string_append (&auth_command, + "\r\n")) + { + _dbus_string_free (&auth_command); + return FALSE; + } + + if (!_dbus_string_copy (&auth_command, 0, + &auth->outgoing, + _dbus_string_get_length (&auth->outgoing))) + { + _dbus_string_free (&auth_command); + return FALSE; + } + + _dbus_string_free (&auth_command); + shutdown_mech (auth); + auth->mech = mech; + goto_state (auth, &client_state_waiting_for_data); + + return TRUE; +} + +static dbus_bool_t +send_data (DBusAuth *auth, DBusString *data) +{ + int old_len; + + if (data == NULL || _dbus_string_get_length (data) == 0) + return _dbus_string_append (&auth->outgoing, "DATA\r\n"); + else + { + old_len = _dbus_string_get_length (&auth->outgoing); + if (!_dbus_string_append (&auth->outgoing, "DATA ")) + goto out; + + if (!_dbus_string_hex_encode (data, 0, &auth->outgoing, + _dbus_string_get_length (&auth->outgoing))) + goto out; + + if (!_dbus_string_append (&auth->outgoing, "\r\n")) + goto out; + + return TRUE; + + out: + _dbus_string_set_length (&auth->outgoing, old_len); + + return FALSE; + } +} + +static dbus_bool_t +send_rejected (DBusAuth *auth) +{ + DBusString command; + DBusAuthServer *server_auth; + int i; + + if (!_dbus_string_init (&command)) + return FALSE; + + if (!_dbus_string_append (&command, + "REJECTED")) + goto nomem; + + for (i = 0; all_mechanisms[i].mechanism != NULL; i++) + { + /* skip mechanisms that aren't allowed */ + if (auth->allowed_mechs != NULL && + !_dbus_string_array_contains ((const char**)auth->allowed_mechs, + all_mechanisms[i].mechanism)) + continue; + + if (!_dbus_string_append (&command, + " ")) + goto nomem; + + if (!_dbus_string_append (&command, + all_mechanisms[i].mechanism)) + goto nomem; + } + + if (!_dbus_string_append (&command, "\r\n")) + goto nomem; + + if (!_dbus_string_copy (&command, 0, &auth->outgoing, + _dbus_string_get_length (&auth->outgoing))) + goto nomem; + + shutdown_mech (auth); + + _dbus_assert (DBUS_AUTH_IS_SERVER (auth)); + server_auth = DBUS_AUTH_SERVER (auth); + server_auth->failures += 1; + + if (server_auth->failures >= server_auth->max_failures) + goto_state (auth, &common_state_need_disconnect); + else + goto_state (auth, &server_state_waiting_for_auth); + + _dbus_string_free (&command); + + return TRUE; + + nomem: + _dbus_string_free (&command); + return FALSE; +} + +static dbus_bool_t +send_error (DBusAuth *auth, const char *message) +{ + return _dbus_string_append_printf (&auth->outgoing, + "ERROR \"%s\"\r\n", message); +} + +static dbus_bool_t +send_ok (DBusAuth *auth) +{ + int orig_len; + + orig_len = _dbus_string_get_length (&auth->outgoing); + + if (_dbus_string_append (&auth->outgoing, "OK ") && + _dbus_string_copy (& DBUS_AUTH_SERVER (auth)->guid, + 0, + &auth->outgoing, + _dbus_string_get_length (&auth->outgoing)) && + _dbus_string_append (&auth->outgoing, "\r\n")) + { + goto_state (auth, &server_state_waiting_for_begin); + return TRUE; + } + else + { + _dbus_string_set_length (&auth->outgoing, orig_len); + return FALSE; + } +} + +static dbus_bool_t +send_begin (DBusAuth *auth) +{ + + if (!_dbus_string_append (&auth->outgoing, + "BEGIN\r\n")) + return FALSE; + + goto_state (auth, &common_state_authenticated); + return TRUE; +} + +static dbus_bool_t +process_ok(DBusAuth *auth, + const DBusString *args_from_ok) { + + int end_of_hex; + + /* "args_from_ok" should be the GUID, whitespace already pulled off the front */ + _dbus_assert (_dbus_string_get_length (& DBUS_AUTH_CLIENT (auth)->guid_from_server) == 0); + + /* We decode the hex string to binary, using guid_from_server as scratch... */ + + end_of_hex = 0; + if (!_dbus_string_hex_decode (args_from_ok, 0, &end_of_hex, + & DBUS_AUTH_CLIENT (auth)->guid_from_server, 0)) + return FALSE; + + /* now clear out the scratch */ + _dbus_string_set_length (& DBUS_AUTH_CLIENT (auth)->guid_from_server, 0); + + if (end_of_hex != _dbus_string_get_length (args_from_ok) || + end_of_hex == 0) + { + _dbus_verbose ("Bad GUID from server, parsed %d bytes and had %d bytes from server\n", + end_of_hex, _dbus_string_get_length (args_from_ok)); + goto_state (auth, &common_state_need_disconnect); + return TRUE; + } + + if (!_dbus_string_copy (args_from_ok, 0, &DBUS_AUTH_CLIENT (auth)->guid_from_server, 0)) { + _dbus_string_set_length (& DBUS_AUTH_CLIENT (auth)->guid_from_server, 0); + return FALSE; + } + + _dbus_verbose ("Got GUID '%s' from the server\n", + _dbus_string_get_const_data (& DBUS_AUTH_CLIENT (auth)->guid_from_server)); + + if (auth->unix_fd_possible) + { + if (!send_negotiate_unix_fd (auth)) + { + _dbus_string_set_length (& DBUS_AUTH_CLIENT (auth)->guid_from_server, 0); + return FALSE; + } + + return TRUE; + } + + _dbus_verbose("Not negotiating unix fd passing, since not possible\n"); + + if (!send_begin (auth)) + { + _dbus_string_set_length (& DBUS_AUTH_CLIENT (auth)->guid_from_server, 0); + return FALSE; + } + + return TRUE; +} + +static dbus_bool_t +send_cancel (DBusAuth *auth) +{ + if (_dbus_string_append (&auth->outgoing, "CANCEL\r\n")) + { + goto_state (auth, &client_state_waiting_for_reject); + return TRUE; + } + else + return FALSE; +} + +static dbus_bool_t +process_data (DBusAuth *auth, + const DBusString *args, + DBusAuthDataFunction data_func) +{ + int end; + DBusString decoded; + + if (!_dbus_string_init (&decoded)) + return FALSE; + + if (!_dbus_string_hex_decode (args, 0, &end, &decoded, 0)) + { + _dbus_string_free (&decoded); + return FALSE; + } + + if (_dbus_string_get_length (args) != end) + { + _dbus_string_free (&decoded); + if (!send_error (auth, "Invalid hex encoding")) + return FALSE; + + return TRUE; + } + +#ifdef DBUS_ENABLE_VERBOSE_MODE + if (_dbus_string_validate_ascii (&decoded, 0, + _dbus_string_get_length (&decoded))) + _dbus_verbose ("%s: data: '%s'\n", + DBUS_AUTH_NAME (auth), + _dbus_string_get_const_data (&decoded)); +#endif + + if (!(* data_func) (auth, &decoded)) + { + _dbus_string_free (&decoded); + return FALSE; + } + + _dbus_string_free (&decoded); + return TRUE; +} + +static dbus_bool_t +send_negotiate_unix_fd (DBusAuth *auth) +{ + if (!_dbus_string_append (&auth->outgoing, + "NEGOTIATE_UNIX_FD\r\n")) + return FALSE; + + goto_state (auth, &client_state_waiting_for_agree_unix_fd); + return TRUE; +} + +static dbus_bool_t +send_agree_unix_fd (DBusAuth *auth) +{ + _dbus_assert(auth->unix_fd_possible); + + auth->unix_fd_negotiated = TRUE; + _dbus_verbose("Agreed to UNIX FD passing\n"); + + if (!_dbus_string_append (&auth->outgoing, + "AGREE_UNIX_FD\r\n")) + return FALSE; + + goto_state (auth, &server_state_waiting_for_begin); + return TRUE; +} + +static dbus_bool_t +handle_auth (DBusAuth *auth, const DBusString *args) +{ + if (_dbus_string_get_length (args) == 0) + { + /* No args to the auth, send mechanisms */ + if (!send_rejected (auth)) + return FALSE; + + return TRUE; + } + else + { + int i; + DBusString mech; + DBusString hex_response; + + _dbus_string_find_blank (args, 0, &i); + + if (!_dbus_string_init (&mech)) + return FALSE; + + if (!_dbus_string_init (&hex_response)) + { + _dbus_string_free (&mech); + return FALSE; + } + + if (!_dbus_string_copy_len (args, 0, i, &mech, 0)) + goto failed; + + _dbus_string_skip_blank (args, i, &i); + if (!_dbus_string_copy (args, i, &hex_response, 0)) + goto failed; + + auth->mech = find_mech (&mech, auth->allowed_mechs); + if (auth->mech != NULL) + { + _dbus_verbose ("%s: Trying mechanism %s\n", + DBUS_AUTH_NAME (auth), + auth->mech->mechanism); + + if (!process_data (auth, &hex_response, + auth->mech->server_data_func)) + goto failed; + } + else + { + /* Unsupported mechanism */ + _dbus_verbose ("%s: Unsupported mechanism %s\n", + DBUS_AUTH_NAME (auth), + _dbus_string_get_const_data (&mech)); + + if (!send_rejected (auth)) + goto failed; + } + + _dbus_string_free (&mech); + _dbus_string_free (&hex_response); + + return TRUE; + + failed: + auth->mech = NULL; + _dbus_string_free (&mech); + _dbus_string_free (&hex_response); + return FALSE; + } +} + +static dbus_bool_t +handle_server_state_waiting_for_auth (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args) +{ + switch (command) + { + case DBUS_AUTH_COMMAND_AUTH: + return handle_auth (auth, args); + + case DBUS_AUTH_COMMAND_CANCEL: + case DBUS_AUTH_COMMAND_DATA: + return send_error (auth, "Not currently in an auth conversation"); + + case DBUS_AUTH_COMMAND_BEGIN: + goto_state (auth, &common_state_need_disconnect); + return TRUE; + + case DBUS_AUTH_COMMAND_ERROR: + return send_rejected (auth); + + case DBUS_AUTH_COMMAND_NEGOTIATE_UNIX_FD: + return send_error (auth, "Need to authenticate first"); + + case DBUS_AUTH_COMMAND_REJECTED: + case DBUS_AUTH_COMMAND_OK: + case DBUS_AUTH_COMMAND_UNKNOWN: + case DBUS_AUTH_COMMAND_AGREE_UNIX_FD: + default: + return send_error (auth, "Unknown command"); + } +} + +static dbus_bool_t +handle_server_state_waiting_for_data (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args) +{ + switch (command) + { + case DBUS_AUTH_COMMAND_AUTH: + return send_error (auth, "Sent AUTH while another AUTH in progress"); + + case DBUS_AUTH_COMMAND_CANCEL: + case DBUS_AUTH_COMMAND_ERROR: + return send_rejected (auth); + + case DBUS_AUTH_COMMAND_DATA: + return process_data (auth, args, auth->mech->server_data_func); + + case DBUS_AUTH_COMMAND_BEGIN: + goto_state (auth, &common_state_need_disconnect); + return TRUE; + + case DBUS_AUTH_COMMAND_NEGOTIATE_UNIX_FD: + return send_error (auth, "Need to authenticate first"); + + case DBUS_AUTH_COMMAND_REJECTED: + case DBUS_AUTH_COMMAND_OK: + case DBUS_AUTH_COMMAND_UNKNOWN: + case DBUS_AUTH_COMMAND_AGREE_UNIX_FD: + default: + return send_error (auth, "Unknown command"); + } +} + +static dbus_bool_t +handle_server_state_waiting_for_begin (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args) +{ + switch (command) + { + case DBUS_AUTH_COMMAND_AUTH: + return send_error (auth, "Sent AUTH while expecting BEGIN"); + + case DBUS_AUTH_COMMAND_DATA: + return send_error (auth, "Sent DATA while expecting BEGIN"); + + case DBUS_AUTH_COMMAND_BEGIN: + goto_state (auth, &common_state_authenticated); + return TRUE; + + case DBUS_AUTH_COMMAND_NEGOTIATE_UNIX_FD: + if (auth->unix_fd_possible) + return send_agree_unix_fd(auth); + else + return send_error(auth, "Unix FD passing not supported, not authenticated or otherwise not possible"); + + case DBUS_AUTH_COMMAND_REJECTED: + case DBUS_AUTH_COMMAND_OK: + case DBUS_AUTH_COMMAND_UNKNOWN: + case DBUS_AUTH_COMMAND_AGREE_UNIX_FD: + default: + return send_error (auth, "Unknown command"); + + case DBUS_AUTH_COMMAND_CANCEL: + case DBUS_AUTH_COMMAND_ERROR: + return send_rejected (auth); + } +} + +/* return FALSE if no memory, TRUE if all OK */ +static dbus_bool_t +get_word (const DBusString *str, + int *start, + DBusString *word) +{ + int i; + + _dbus_string_skip_blank (str, *start, start); + _dbus_string_find_blank (str, *start, &i); + + if (i > *start) + { + if (!_dbus_string_copy_len (str, *start, i - *start, word, 0)) + return FALSE; + + *start = i; + } + + return TRUE; +} + +static dbus_bool_t +record_mechanisms (DBusAuth *auth, + const DBusString *args) +{ + int next; + int len; + + if (auth->already_got_mechanisms) + return TRUE; + + len = _dbus_string_get_length (args); + + next = 0; + while (next < len) + { + DBusString m; + const DBusAuthMechanismHandler *mech; + + if (!_dbus_string_init (&m)) + goto nomem; + + if (!get_word (args, &next, &m)) + { + _dbus_string_free (&m); + goto nomem; + } + + mech = find_mech (&m, auth->allowed_mechs); + + if (mech != NULL) + { + /* FIXME right now we try mechanisms in the order + * the server lists them; should we do them in + * some more deterministic order? + * + * Probably in all_mechanisms order, our order of + * preference. Of course when the server is us, + * it lists things in that order anyhow. + */ + + if (mech != &all_mechanisms[0]) + { + _dbus_verbose ("%s: Adding mechanism %s to list we will try\n", + DBUS_AUTH_NAME (auth), mech->mechanism); + + if (!_dbus_list_append (& DBUS_AUTH_CLIENT (auth)->mechs_to_try, + (void*) mech)) + { + _dbus_string_free (&m); + goto nomem; + } + } + else + { + _dbus_verbose ("%s: Already tried mechanism %s; not adding to list we will try\n", + DBUS_AUTH_NAME (auth), mech->mechanism); + } + } + else + { + _dbus_verbose ("%s: Server offered mechanism \"%s\" that we don't know how to use\n", + DBUS_AUTH_NAME (auth), + _dbus_string_get_const_data (&m)); + } + + _dbus_string_free (&m); + } + + auth->already_got_mechanisms = TRUE; + + return TRUE; + + nomem: + _dbus_list_clear (& DBUS_AUTH_CLIENT (auth)->mechs_to_try); + + return FALSE; +} + +static dbus_bool_t +process_rejected (DBusAuth *auth, const DBusString *args) +{ + const DBusAuthMechanismHandler *mech; + DBusAuthClient *client; + + client = DBUS_AUTH_CLIENT (auth); + + if (!auth->already_got_mechanisms) + { + if (!record_mechanisms (auth, args)) + return FALSE; + } + + if (DBUS_AUTH_CLIENT (auth)->mechs_to_try != NULL) + { + mech = client->mechs_to_try->data; + + if (!send_auth (auth, mech)) + return FALSE; + + _dbus_list_pop_first (&client->mechs_to_try); + + _dbus_verbose ("%s: Trying mechanism %s\n", + DBUS_AUTH_NAME (auth), + mech->mechanism); + } + else + { + /* Give up */ + _dbus_verbose ("%s: Disconnecting because we are out of mechanisms to try using\n", + DBUS_AUTH_NAME (auth)); + goto_state (auth, &common_state_need_disconnect); + } + + return TRUE; +} + + +static dbus_bool_t +handle_client_state_waiting_for_data (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args) +{ + _dbus_assert (auth->mech != NULL); + + switch (command) + { + case DBUS_AUTH_COMMAND_DATA: + return process_data (auth, args, auth->mech->client_data_func); + + case DBUS_AUTH_COMMAND_REJECTED: + return process_rejected (auth, args); + + case DBUS_AUTH_COMMAND_OK: + return process_ok(auth, args); + + case DBUS_AUTH_COMMAND_ERROR: + return send_cancel (auth); + + case DBUS_AUTH_COMMAND_AUTH: + case DBUS_AUTH_COMMAND_CANCEL: + case DBUS_AUTH_COMMAND_BEGIN: + case DBUS_AUTH_COMMAND_UNKNOWN: + case DBUS_AUTH_COMMAND_NEGOTIATE_UNIX_FD: + case DBUS_AUTH_COMMAND_AGREE_UNIX_FD: + default: + return send_error (auth, "Unknown command"); + } +} + +static dbus_bool_t +handle_client_state_waiting_for_ok (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args) +{ + switch (command) + { + case DBUS_AUTH_COMMAND_REJECTED: + return process_rejected (auth, args); + + case DBUS_AUTH_COMMAND_OK: + return process_ok(auth, args); + + case DBUS_AUTH_COMMAND_DATA: + case DBUS_AUTH_COMMAND_ERROR: + return send_cancel (auth); + + case DBUS_AUTH_COMMAND_AUTH: + case DBUS_AUTH_COMMAND_CANCEL: + case DBUS_AUTH_COMMAND_BEGIN: + case DBUS_AUTH_COMMAND_UNKNOWN: + case DBUS_AUTH_COMMAND_NEGOTIATE_UNIX_FD: + case DBUS_AUTH_COMMAND_AGREE_UNIX_FD: + default: + return send_error (auth, "Unknown command"); + } +} + +static dbus_bool_t +handle_client_state_waiting_for_reject (DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args) +{ + switch (command) + { + case DBUS_AUTH_COMMAND_REJECTED: + return process_rejected (auth, args); + + case DBUS_AUTH_COMMAND_AUTH: + case DBUS_AUTH_COMMAND_CANCEL: + case DBUS_AUTH_COMMAND_DATA: + case DBUS_AUTH_COMMAND_BEGIN: + case DBUS_AUTH_COMMAND_OK: + case DBUS_AUTH_COMMAND_ERROR: + case DBUS_AUTH_COMMAND_UNKNOWN: + case DBUS_AUTH_COMMAND_NEGOTIATE_UNIX_FD: + case DBUS_AUTH_COMMAND_AGREE_UNIX_FD: + default: + goto_state (auth, &common_state_need_disconnect); + return TRUE; + } +} + +static dbus_bool_t +handle_client_state_waiting_for_agree_unix_fd(DBusAuth *auth, + DBusAuthCommand command, + const DBusString *args) +{ + switch (command) + { + case DBUS_AUTH_COMMAND_AGREE_UNIX_FD: + _dbus_assert(auth->unix_fd_possible); + auth->unix_fd_negotiated = TRUE; + _dbus_verbose("Successfully negotiated UNIX FD passing\n"); + return send_begin (auth); + + case DBUS_AUTH_COMMAND_ERROR: + _dbus_assert(auth->unix_fd_possible); + auth->unix_fd_negotiated = FALSE; + _dbus_verbose("Failed to negotiate UNIX FD passing\n"); + return send_begin (auth); + + case DBUS_AUTH_COMMAND_OK: + case DBUS_AUTH_COMMAND_DATA: + case DBUS_AUTH_COMMAND_REJECTED: + case DBUS_AUTH_COMMAND_AUTH: + case DBUS_AUTH_COMMAND_CANCEL: + case DBUS_AUTH_COMMAND_BEGIN: + case DBUS_AUTH_COMMAND_UNKNOWN: + case DBUS_AUTH_COMMAND_NEGOTIATE_UNIX_FD: + default: + return send_error (auth, "Unknown command"); + } +} + +/** + * Mapping from command name to enum + */ +typedef struct { + const char *name; /**< Name of the command */ + DBusAuthCommand command; /**< Corresponding enum */ +} DBusAuthCommandName; + +static const DBusAuthCommandName auth_command_names[] = { + { "AUTH", DBUS_AUTH_COMMAND_AUTH }, + { "CANCEL", DBUS_AUTH_COMMAND_CANCEL }, + { "DATA", DBUS_AUTH_COMMAND_DATA }, + { "BEGIN", DBUS_AUTH_COMMAND_BEGIN }, + { "REJECTED", DBUS_AUTH_COMMAND_REJECTED }, + { "OK", DBUS_AUTH_COMMAND_OK }, + { "ERROR", DBUS_AUTH_COMMAND_ERROR }, + { "NEGOTIATE_UNIX_FD", DBUS_AUTH_COMMAND_NEGOTIATE_UNIX_FD }, + { "AGREE_UNIX_FD", DBUS_AUTH_COMMAND_AGREE_UNIX_FD } +}; + +static DBusAuthCommand +lookup_command_from_name (DBusString *command) +{ + int i; + + for (i = 0; i < _DBUS_N_ELEMENTS (auth_command_names); i++) + { + if (_dbus_string_equal_c_str (command, + auth_command_names[i].name)) + return auth_command_names[i].command; + } + + return DBUS_AUTH_COMMAND_UNKNOWN; +} + +static void +goto_state (DBusAuth *auth, + const DBusAuthStateData *state) +{ + _dbus_verbose ("%s: going from state %s to state %s\n", + DBUS_AUTH_NAME (auth), + auth->state->name, + state->name); + + auth->state = state; +} + +/* returns whether to call it again right away */ +static dbus_bool_t +process_command (DBusAuth *auth) +{ + DBusAuthCommand command; + DBusString line; + DBusString args; + int eol; + int i, j; + dbus_bool_t retval; + + /* _dbus_verbose ("%s: trying process_command()\n"); */ + + retval = FALSE; + + eol = 0; + if (!_dbus_string_find (&auth->incoming, 0, "\r\n", &eol)) + return FALSE; + + if (!_dbus_string_init (&line)) + { + auth->needed_memory = TRUE; + return FALSE; + } + + if (!_dbus_string_init (&args)) + { + _dbus_string_free (&line); + auth->needed_memory = TRUE; + return FALSE; + } + + if (!_dbus_string_copy_len (&auth->incoming, 0, eol, &line, 0)) + goto out; + + if (!_dbus_string_validate_ascii (&line, 0, + _dbus_string_get_length (&line))) + { + _dbus_verbose ("%s: Command contained non-ASCII chars or embedded nul\n", + DBUS_AUTH_NAME (auth)); + if (!send_error (auth, "Command contained non-ASCII")) + goto out; + else + goto next_command; + } + + _dbus_verbose ("%s: got command \"%s\"\n", + DBUS_AUTH_NAME (auth), + _dbus_string_get_const_data (&line)); + + _dbus_string_find_blank (&line, 0, &i); + _dbus_string_skip_blank (&line, i, &j); + + if (j > i) + _dbus_string_delete (&line, i, j - i); + + if (!_dbus_string_move (&line, i, &args, 0)) + goto out; + + /* FIXME 1.0 we should probably validate that only the allowed + * chars are in the command name + */ + + command = lookup_command_from_name (&line); + if (!(* auth->state->handler) (auth, command, &args)) + goto out; + + next_command: + + /* We've succeeded in processing the whole command so drop it out + * of the incoming buffer and return TRUE to try another command. + */ + + _dbus_string_delete (&auth->incoming, 0, eol); + + /* kill the \r\n */ + _dbus_string_delete (&auth->incoming, 0, 2); + + retval = TRUE; + + out: + _dbus_string_free (&args); + _dbus_string_free (&line); + + if (!retval) + auth->needed_memory = TRUE; + else + auth->needed_memory = FALSE; + + return retval; +} + + +/** @} */ + +/** + * @addtogroup DBusAuth + * @{ + */ + +/** + * Creates a new auth conversation object for the server side. + * See http://dbus.freedesktop.org/doc/dbus-specification.html#auth-protocol + * for full details on what this object does. + * + * @returns the new object or #NULL if no memory + */ +DBusAuth* +_dbus_auth_server_new (const DBusString *guid) +{ + DBusAuth *auth; + DBusAuthServer *server_auth; + DBusString guid_copy; + + if (!_dbus_string_init (&guid_copy)) + return NULL; + + if (!_dbus_string_copy (guid, 0, &guid_copy, 0)) + { + _dbus_string_free (&guid_copy); + return NULL; + } + + auth = _dbus_auth_new (sizeof (DBusAuthServer)); + if (auth == NULL) + { + _dbus_string_free (&guid_copy); + return NULL; + } + + auth->side = auth_side_server; + auth->state = &server_state_waiting_for_auth; + + server_auth = DBUS_AUTH_SERVER (auth); + + server_auth->guid = guid_copy; + + /* perhaps this should be per-mechanism with a lower + * max + */ + server_auth->failures = 0; + server_auth->max_failures = 6; + + return auth; +} + +/** + * Creates a new auth conversation object for the client side. + * See http://dbus.freedesktop.org/doc/dbus-specification.html#auth-protocol + * for full details on what this object does. + * + * @returns the new object or #NULL if no memory + */ +DBusAuth* +_dbus_auth_client_new (void) +{ + DBusAuth *auth; + DBusString guid_str; + + if (!_dbus_string_init (&guid_str)) + return NULL; + + auth = _dbus_auth_new (sizeof (DBusAuthClient)); + if (auth == NULL) + { + _dbus_string_free (&guid_str); + return NULL; + } + + DBUS_AUTH_CLIENT (auth)->guid_from_server = guid_str; + + auth->side = auth_side_client; + auth->state = &client_state_need_send_auth; + + /* Start the auth conversation by sending AUTH for our default + * mechanism */ + if (!send_auth (auth, &all_mechanisms[0])) + { + _dbus_auth_unref (auth); + return NULL; + } + + return auth; +} + +/** + * Increments the refcount of an auth object. + * + * @param auth the auth conversation + * @returns the auth conversation + */ +DBusAuth * +_dbus_auth_ref (DBusAuth *auth) +{ + _dbus_assert (auth != NULL); + + auth->refcount += 1; + + return auth; +} + +/** + * Decrements the refcount of an auth object. + * + * @param auth the auth conversation + */ +void +_dbus_auth_unref (DBusAuth *auth) +{ + _dbus_assert (auth != NULL); + _dbus_assert (auth->refcount > 0); + + auth->refcount -= 1; + if (auth->refcount == 0) + { + shutdown_mech (auth); + + if (DBUS_AUTH_IS_CLIENT (auth)) + { + _dbus_string_free (& DBUS_AUTH_CLIENT (auth)->guid_from_server); + _dbus_list_clear (& DBUS_AUTH_CLIENT (auth)->mechs_to_try); + } + else + { + _dbus_assert (DBUS_AUTH_IS_SERVER (auth)); + + _dbus_string_free (& DBUS_AUTH_SERVER (auth)->guid); + } + + if (auth->keyring) + _dbus_keyring_unref (auth->keyring); + + _dbus_string_free (&auth->context); + _dbus_string_free (&auth->challenge); + _dbus_string_free (&auth->identity); + _dbus_string_free (&auth->incoming); + _dbus_string_free (&auth->outgoing); + + dbus_free_string_array (auth->allowed_mechs); + + _dbus_credentials_unref (auth->credentials); + _dbus_credentials_unref (auth->authorized_identity); + _dbus_credentials_unref (auth->desired_identity); + + dbus_free (auth); + } +} + +/** + * Sets an array of authentication mechanism names + * that we are willing to use. + * + * @param auth the auth conversation + * @param mechanisms #NULL-terminated array of mechanism names + * @returns #FALSE if no memory + */ +dbus_bool_t +_dbus_auth_set_mechanisms (DBusAuth *auth, + const char **mechanisms) +{ + char **copy; + + if (mechanisms != NULL) + { + copy = _dbus_dup_string_array (mechanisms); + if (copy == NULL) + return FALSE; + } + else + copy = NULL; + + dbus_free_string_array (auth->allowed_mechs); + + auth->allowed_mechs = copy; + + return TRUE; +} + +/** + * @param auth the auth conversation object + * @returns #TRUE if we're in a final state + */ +#define DBUS_AUTH_IN_END_STATE(auth) ((auth)->state->handler == NULL) + +/** + * Analyzes buffered input and moves the auth conversation forward, + * returning the new state of the auth conversation. + * + * @param auth the auth conversation + * @returns the new state + */ +DBusAuthState +_dbus_auth_do_work (DBusAuth *auth) +{ + auth->needed_memory = FALSE; + + /* Max amount we'll buffer up before deciding someone's on crack */ +#define MAX_BUFFER (16 * _DBUS_ONE_KILOBYTE) + + do + { + if (DBUS_AUTH_IN_END_STATE (auth)) + break; + + if (_dbus_string_get_length (&auth->incoming) > MAX_BUFFER || + _dbus_string_get_length (&auth->outgoing) > MAX_BUFFER) + { + goto_state (auth, &common_state_need_disconnect); + _dbus_verbose ("%s: Disconnecting due to excessive data buffered in auth phase\n", + DBUS_AUTH_NAME (auth)); + break; + } + } + while (process_command (auth)); + + if (auth->needed_memory) + return DBUS_AUTH_STATE_WAITING_FOR_MEMORY; + else if (_dbus_string_get_length (&auth->outgoing) > 0) + return DBUS_AUTH_STATE_HAVE_BYTES_TO_SEND; + else if (auth->state == &common_state_need_disconnect) + return DBUS_AUTH_STATE_NEED_DISCONNECT; + else if (auth->state == &common_state_authenticated) + return DBUS_AUTH_STATE_AUTHENTICATED; + else return DBUS_AUTH_STATE_WAITING_FOR_INPUT; +} + +/** + * Gets bytes that need to be sent to the peer we're conversing with. + * After writing some bytes, _dbus_auth_bytes_sent() must be called + * to notify the auth object that they were written. + * + * @param auth the auth conversation + * @param str return location for a ref to the buffer to send + * @returns #FALSE if nothing to send + */ +dbus_bool_t +_dbus_auth_get_bytes_to_send (DBusAuth *auth, + const DBusString **str) +{ + _dbus_assert (auth != NULL); + _dbus_assert (str != NULL); + + *str = NULL; + + if (_dbus_string_get_length (&auth->outgoing) == 0) + return FALSE; + + *str = &auth->outgoing; + + return TRUE; +} + +/** + * Notifies the auth conversation object that + * the given number of bytes of the outgoing buffer + * have been written out. + * + * @param auth the auth conversation + * @param bytes_sent number of bytes written out + */ +void +_dbus_auth_bytes_sent (DBusAuth *auth, + int bytes_sent) +{ + _dbus_verbose ("%s: Sent %d bytes of: %s\n", + DBUS_AUTH_NAME (auth), + bytes_sent, + _dbus_string_get_const_data (&auth->outgoing)); + + _dbus_string_delete (&auth->outgoing, + 0, bytes_sent); +} + +/** + * Get a buffer to be used for reading bytes from the peer we're conversing + * with. Bytes should be appended to this buffer. + * + * @param auth the auth conversation + * @param buffer return location for buffer to append bytes to + */ +void +_dbus_auth_get_buffer (DBusAuth *auth, + DBusString **buffer) +{ + _dbus_assert (auth != NULL); + _dbus_assert (!auth->buffer_outstanding); + + *buffer = &auth->incoming; + + auth->buffer_outstanding = TRUE; +} + +/** + * Returns a buffer with new data read into it. + * + * @param auth the auth conversation + * @param buffer the buffer being returned + */ +void +_dbus_auth_return_buffer (DBusAuth *auth, + DBusString *buffer) +{ + _dbus_assert (buffer == &auth->incoming); + _dbus_assert (auth->buffer_outstanding); + + auth->buffer_outstanding = FALSE; +} + +/** + * Returns leftover bytes that were not used as part of the auth + * conversation. These bytes will be part of the message stream + * instead. This function may not be called until authentication has + * succeeded. + * + * @param auth the auth conversation + * @param str return location for pointer to string of unused bytes + */ +void +_dbus_auth_get_unused_bytes (DBusAuth *auth, + const DBusString **str) +{ + if (!DBUS_AUTH_IN_END_STATE (auth)) + return; + + *str = &auth->incoming; +} + + +/** + * Gets rid of unused bytes returned by _dbus_auth_get_unused_bytes() + * after we've gotten them and successfully moved them elsewhere. + * + * @param auth the auth conversation + */ +void +_dbus_auth_delete_unused_bytes (DBusAuth *auth) +{ + if (!DBUS_AUTH_IN_END_STATE (auth)) + return; + + _dbus_string_set_length (&auth->incoming, 0); +} + +/** + * Called post-authentication, indicates whether we need to encode + * the message stream with _dbus_auth_encode_data() prior to + * sending it to the peer. + * + * @param auth the auth conversation + * @returns #TRUE if we need to encode the stream + */ +dbus_bool_t +_dbus_auth_needs_encoding (DBusAuth *auth) +{ + if (auth->state != &common_state_authenticated) + return FALSE; + + if (auth->mech != NULL) + { + if (DBUS_AUTH_IS_CLIENT (auth)) + return auth->mech->client_encode_func != NULL; + else + return auth->mech->server_encode_func != NULL; + } + else + return FALSE; +} + +/** + * Called post-authentication, encodes a block of bytes for sending to + * the peer. If no encoding was negotiated, just copies the bytes + * (you can avoid this by checking _dbus_auth_needs_encoding()). + * + * @param auth the auth conversation + * @param plaintext the plain text data + * @param encoded initialized string to where encoded data is appended + * @returns #TRUE if we had enough memory and successfully encoded + */ +dbus_bool_t +_dbus_auth_encode_data (DBusAuth *auth, + const DBusString *plaintext, + DBusString *encoded) +{ + _dbus_assert (plaintext != encoded); + + if (auth->state != &common_state_authenticated) + return FALSE; + + if (_dbus_auth_needs_encoding (auth)) + { + if (DBUS_AUTH_IS_CLIENT (auth)) + return (* auth->mech->client_encode_func) (auth, plaintext, encoded); + else + return (* auth->mech->server_encode_func) (auth, plaintext, encoded); + } + else + { + return _dbus_string_copy (plaintext, 0, encoded, + _dbus_string_get_length (encoded)); + } +} + +/** + * Called post-authentication, indicates whether we need to decode + * the message stream with _dbus_auth_decode_data() after + * receiving it from the peer. + * + * @param auth the auth conversation + * @returns #TRUE if we need to encode the stream + */ +dbus_bool_t +_dbus_auth_needs_decoding (DBusAuth *auth) +{ + if (auth->state != &common_state_authenticated) + return FALSE; + + if (auth->mech != NULL) + { + if (DBUS_AUTH_IS_CLIENT (auth)) + return auth->mech->client_decode_func != NULL; + else + return auth->mech->server_decode_func != NULL; + } + else + return FALSE; +} + + +/** + * Called post-authentication, decodes a block of bytes received from + * the peer. If no encoding was negotiated, just copies the bytes (you + * can avoid this by checking _dbus_auth_needs_decoding()). + * + * @todo 1.0? We need to be able to distinguish "out of memory" error + * from "the data is hosed" error. + * + * @param auth the auth conversation + * @param encoded the encoded data + * @param plaintext initialized string where decoded data is appended + * @returns #TRUE if we had enough memory and successfully decoded + */ +dbus_bool_t +_dbus_auth_decode_data (DBusAuth *auth, + const DBusString *encoded, + DBusString *plaintext) +{ + _dbus_assert (plaintext != encoded); + + if (auth->state != &common_state_authenticated) + return FALSE; + + if (_dbus_auth_needs_decoding (auth)) + { + if (DBUS_AUTH_IS_CLIENT (auth)) + return (* auth->mech->client_decode_func) (auth, encoded, plaintext); + else + return (* auth->mech->server_decode_func) (auth, encoded, plaintext); + } + else + { + return _dbus_string_copy (encoded, 0, plaintext, + _dbus_string_get_length (plaintext)); + } +} + +/** + * Sets credentials received via reliable means from the operating + * system. + * + * @param auth the auth conversation + * @param credentials the credentials received + * @returns #FALSE on OOM + */ +dbus_bool_t +_dbus_auth_set_credentials (DBusAuth *auth, + DBusCredentials *credentials) +{ + _dbus_credentials_clear (auth->credentials); + return _dbus_credentials_add_credentials (auth->credentials, + credentials); +} + +/** + * Gets the identity we authorized the client as. Apps may have + * different policies as to what identities they allow. + * + * Returned credentials are not a copy and should not be modified + * + * @param auth the auth conversation + * @returns the credentials we've authorized BY REFERENCE do not modify + */ +DBusCredentials* +_dbus_auth_get_identity (DBusAuth *auth) +{ + if (auth->state == &common_state_authenticated) + { + return auth->authorized_identity; + } + else + { + /* FIXME instead of this, keep an empty credential around that + * doesn't require allocation or something + */ + /* return empty credentials */ + _dbus_assert (_dbus_credentials_are_empty (auth->authorized_identity)); + return auth->authorized_identity; + } +} + +/** + * Gets the GUID from the server if we've authenticated; gets + * #NULL otherwise. + * @param auth the auth object + * @returns the GUID in ASCII hex format + */ +const char* +_dbus_auth_get_guid_from_server (DBusAuth *auth) +{ + _dbus_assert (DBUS_AUTH_IS_CLIENT (auth)); + + if (auth->state == &common_state_authenticated) + return _dbus_string_get_const_data (& DBUS_AUTH_CLIENT (auth)->guid_from_server); + else + return NULL; +} + +/** + * Sets the "authentication context" which scopes cookies + * with the DBUS_COOKIE_SHA1 auth mechanism for example. + * + * @param auth the auth conversation + * @param context the context + * @returns #FALSE if no memory + */ +dbus_bool_t +_dbus_auth_set_context (DBusAuth *auth, + const DBusString *context) +{ + return _dbus_string_replace_len (context, 0, _dbus_string_get_length (context), + &auth->context, 0, _dbus_string_get_length (context)); +} + +/** + * Sets whether unix fd passing is potentially on the transport and + * hence shall be negotiated. + * + * @param auth the auth conversation + * @param b TRUE when unix fd passing shall be negotiated, otherwise FALSE + */ +void +_dbus_auth_set_unix_fd_possible(DBusAuth *auth, dbus_bool_t b) +{ + auth->unix_fd_possible = b; +} + +/** + * Queries whether unix fd passing was successfully negotiated. + * + * @param auth the auth conversion + * @returns #TRUE when unix fd passing was negotiated. + */ +dbus_bool_t +_dbus_auth_get_unix_fd_negotiated(DBusAuth *auth) +{ + return auth->unix_fd_negotiated; +} + +/** + * Queries whether the given auth mechanism is supported. + * + * @param auth the auth mechanism to query for + * @returns #TRUE when auth mechanism is supported + */ +dbus_bool_t +_dbus_auth_is_supported_mechanism (DBusString *name) +{ + _dbus_assert (name != NULL); + + return find_mech (name, NULL) != NULL; +} + +/** + * Return a human-readable string containing all supported auth mechanisms. + * + * @param string to hold the supported auth mechanisms + * @returns #FALSE on oom + */ +dbus_bool_t +_dbus_auth_dump_supported_mechanisms (DBusString *buffer) +{ + unsigned int i; + _dbus_assert (buffer != NULL); + + for (i = 0; all_mechanisms[i].mechanism != NULL; i++) + { + if (i > 0) + { + if (!_dbus_string_append (buffer, ", ")) + return FALSE; + } + if (!_dbus_string_append (buffer, all_mechanisms[i].mechanism)) + return FALSE; + } + return TRUE; +} + +/** @} */ + +/* tests in dbus-auth-util.c */ |