diff -r 000000000000 -r bde4ae8d615e os/ossrv/ofdbus/dbus/bus/policy.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/os/ossrv/ofdbus/dbus/bus/policy.c Fri Jun 15 03:10:57 2012 +0200 @@ -0,0 +1,1263 @@ +/* -*- mode: C; c-file-style: "gnu" -*- */ +/* policy.c Bus security policy + * + * Copyright (C) 2003, 2004 Red Hat, Inc. + * Portion Copyright © 2008 Nokia Corporation and/or its subsidiary(-ies). All rights reserved. + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include "policy.h" +#include "services.h" +#include "test.h" +#include "utils.h" +#ifndef __SYMBIAN32__ +#include +#include +#include +#else +#include "dbus-list.h" +#include "dbus-hash.h" +#include "dbus-internals.h" +#endif //__SYMBIAN32__ + +BusPolicyRule* +bus_policy_rule_new (BusPolicyRuleType type, + dbus_bool_t allow) +{ + BusPolicyRule *rule; + + rule = dbus_new0 (BusPolicyRule, 1); + if (rule == NULL) + return NULL; + + rule->type = type; + rule->refcount = 1; + rule->allow = allow; + + switch (rule->type) + { + case BUS_POLICY_RULE_USER: + rule->d.user.uid = DBUS_UID_UNSET; + break; + case BUS_POLICY_RULE_GROUP: + rule->d.group.gid = DBUS_GID_UNSET; + break; + case BUS_POLICY_RULE_SEND: + rule->d.send.message_type = DBUS_MESSAGE_TYPE_INVALID; + + /* allow rules default to TRUE (only requested replies allowed) + * deny rules default to FALSE (only unrequested replies denied) + */ + rule->d.send.requested_reply = rule->allow; + break; + case BUS_POLICY_RULE_RECEIVE: + rule->d.receive.message_type = DBUS_MESSAGE_TYPE_INVALID; + /* allow rules default to TRUE (only requested replies allowed) + * deny rules default to FALSE (only unrequested replies denied) + */ + rule->d.receive.requested_reply = rule->allow; + break; + case BUS_POLICY_RULE_OWN: + break; + } + + return rule; +} + +BusPolicyRule * +bus_policy_rule_ref (BusPolicyRule *rule) +{ + _dbus_assert (rule->refcount > 0); + + rule->refcount += 1; + + return rule; +} + +void +bus_policy_rule_unref (BusPolicyRule *rule) +{ + _dbus_assert (rule->refcount > 0); + + rule->refcount -= 1; + + if (rule->refcount == 0) + { + switch (rule->type) + { + case BUS_POLICY_RULE_SEND: + dbus_free (rule->d.send.path); + dbus_free (rule->d.send.interface); + dbus_free (rule->d.send.member); + dbus_free (rule->d.send.error); + dbus_free (rule->d.send.destination); + break; + case BUS_POLICY_RULE_RECEIVE: + dbus_free (rule->d.receive.path); + dbus_free (rule->d.receive.interface); + dbus_free (rule->d.receive.member); + dbus_free (rule->d.receive.error); + dbus_free (rule->d.receive.origin); + break; + case BUS_POLICY_RULE_OWN: + dbus_free (rule->d.own.service_name); + break; + case BUS_POLICY_RULE_USER: + break; + case BUS_POLICY_RULE_GROUP: + break; + } + + dbus_free (rule); + } +} + +struct BusPolicy +{ + int refcount; + + DBusList *default_rules; /**< Default policy rules */ + DBusList *mandatory_rules; /**< Mandatory policy rules */ + DBusHashTable *rules_by_uid; /**< per-UID policy rules */ + DBusHashTable *rules_by_gid; /**< per-GID policy rules */ + DBusList *at_console_true_rules; /**< console user policy rules where at_console="true"*/ + DBusList *at_console_false_rules; /**< console user policy rules where at_console="false"*/ +}; + +static void +free_rule_func (void *data, + void *user_data) +{ + BusPolicyRule *rule = data; + + bus_policy_rule_unref (rule); +} + +static void +free_rule_list_func (void *data) +{ + DBusList **list = data; + + if (list == NULL) /* DBusHashTable is on crack */ + return; + + _dbus_list_foreach (list, free_rule_func, NULL); + + _dbus_list_clear (list); + + dbus_free (list); +} + +BusPolicy* +bus_policy_new (void) +{ + BusPolicy *policy; + + policy = dbus_new0 (BusPolicy, 1); + if (policy == NULL) + return NULL; + + policy->refcount = 1; + + policy->rules_by_uid = _dbus_hash_table_new (DBUS_HASH_ULONG, + NULL, + free_rule_list_func); + if (policy->rules_by_uid == NULL) + goto failed; + + policy->rules_by_gid = _dbus_hash_table_new (DBUS_HASH_ULONG, + NULL, + free_rule_list_func); + if (policy->rules_by_gid == NULL) + goto failed; + + return policy; + + failed: + bus_policy_unref (policy); + return NULL; +} + +BusPolicy * +bus_policy_ref (BusPolicy *policy) +{ + _dbus_assert (policy->refcount > 0); + + policy->refcount += 1; + + return policy; +} + +void +bus_policy_unref (BusPolicy *policy) +{ + _dbus_assert (policy->refcount > 0); + + policy->refcount -= 1; + + if (policy->refcount == 0) + { + _dbus_list_foreach (&policy->default_rules, free_rule_func, NULL); + _dbus_list_clear (&policy->default_rules); + + _dbus_list_foreach (&policy->mandatory_rules, free_rule_func, NULL); + _dbus_list_clear (&policy->mandatory_rules); + + _dbus_list_foreach (&policy->at_console_true_rules, free_rule_func, NULL); + _dbus_list_clear (&policy->at_console_true_rules); + + _dbus_list_foreach (&policy->at_console_false_rules, free_rule_func, NULL); + _dbus_list_clear (&policy->at_console_false_rules); + + if (policy->rules_by_uid) + { + _dbus_hash_table_unref (policy->rules_by_uid); + policy->rules_by_uid = NULL; + } + + if (policy->rules_by_gid) + { + _dbus_hash_table_unref (policy->rules_by_gid); + policy->rules_by_gid = NULL; + } + + dbus_free (policy); + } +} + +static dbus_bool_t +add_list_to_client (DBusList **list, + BusClientPolicy *client) +{ + DBusList *link; + + link = _dbus_list_get_first_link (list); + while (link != NULL) + { + BusPolicyRule *rule = link->data; + link = _dbus_list_get_next_link (list, link); + + switch (rule->type) + { + case BUS_POLICY_RULE_USER: + case BUS_POLICY_RULE_GROUP: + /* These aren't per-connection policies */ + break; + + case BUS_POLICY_RULE_OWN: + case BUS_POLICY_RULE_SEND: + case BUS_POLICY_RULE_RECEIVE: + /* These are per-connection */ + if (!bus_client_policy_append_rule (client, rule)) + return FALSE; + break; + } + } + + return TRUE; +} + +BusClientPolicy* +bus_policy_create_client_policy (BusPolicy *policy, + DBusConnection *connection, + DBusError *error) +{ + BusClientPolicy *client; + dbus_uid_t uid; + dbus_bool_t at_console; + + _dbus_assert (dbus_connection_get_is_authenticated (connection)); + _DBUS_ASSERT_ERROR_IS_CLEAR (error); + + client = bus_client_policy_new (); + if (client == NULL) + goto nomem; + + if (!add_list_to_client (&policy->default_rules, + client)) + goto nomem; + + /* we avoid the overhead of looking up user's groups + * if we don't have any group rules anyway + */ + if (_dbus_hash_table_get_n_entries (policy->rules_by_gid) > 0) + { + unsigned long *groups; + int n_groups; + int i; + + if (!bus_connection_get_groups (connection, &groups, &n_groups, error)) + goto failed; + + i = 0; + while (i < n_groups) + { + DBusList **list; + + list = _dbus_hash_table_lookup_ulong (policy->rules_by_gid, + groups[i]); + + if (list != NULL) + { + if (!add_list_to_client (list, client)) + { + dbus_free (groups); + goto nomem; + } + } + + ++i; + } + + dbus_free (groups); + } + + if (!dbus_connection_get_unix_user (connection, &uid)) + { + dbus_set_error (error, DBUS_ERROR_FAILED, + "No user ID known for connection, cannot determine security policy\n"); + goto failed; + } + + if (_dbus_hash_table_get_n_entries (policy->rules_by_uid) > 0) + { + DBusList **list; + + list = _dbus_hash_table_lookup_ulong (policy->rules_by_uid, + uid); + + if (list != NULL) + { + if (!add_list_to_client (list, client)) + goto nomem; + } + } + + /* Add console rules */ + at_console = _dbus_is_console_user (uid, error); + + if (at_console) + { + if (!add_list_to_client (&policy->at_console_true_rules, client)) + goto nomem; + } + else if (dbus_error_is_set (error) == TRUE) + { + goto failed; + } + else if (!add_list_to_client (&policy->at_console_false_rules, client)) + { + goto nomem; + } + + if (!add_list_to_client (&policy->mandatory_rules, + client)) + goto nomem; + + bus_client_policy_optimize (client); + + return client; + + nomem: + BUS_SET_OOM (error); + failed: + _DBUS_ASSERT_ERROR_IS_SET (error); + if (client) + bus_client_policy_unref (client); + return NULL; +} + +static dbus_bool_t +list_allows_user (dbus_bool_t def, + DBusList **list, + unsigned long uid, + const unsigned long *group_ids, + int n_group_ids) +{ + DBusList *link; + dbus_bool_t allowed; + + allowed = def; + + link = _dbus_list_get_first_link (list); + while (link != NULL) + { + BusPolicyRule *rule = link->data; + link = _dbus_list_get_next_link (list, link); + + if (rule->type == BUS_POLICY_RULE_USER) + { + _dbus_verbose ("List %p user rule uid="DBUS_UID_FORMAT"\n", + list, rule->d.user.uid); + + if (rule->d.user.uid == DBUS_UID_UNSET) + ; /* '*' wildcard */ + else if (rule->d.user.uid != uid) + continue; + } + else if (rule->type == BUS_POLICY_RULE_GROUP) + { + _dbus_verbose ("List %p group rule uid="DBUS_UID_FORMAT"\n", + list, rule->d.user.uid); + + if (rule->d.group.gid == DBUS_GID_UNSET) + ; /* '*' wildcard */ + else + { + int i; + + i = 0; + while (i < n_group_ids) + { + if (rule->d.group.gid == group_ids[i]) + break; + ++i; + } + + if (i == n_group_ids) + continue; + } + } + else + continue; + + allowed = rule->allow; + } + + return allowed; +} + +dbus_bool_t +bus_policy_allow_user (BusPolicy *policy, + DBusUserDatabase *user_database, + unsigned long uid) +{ + dbus_bool_t allowed; + unsigned long *group_ids; + int n_group_ids; + + /* On OOM or error we always reject the user */ + if (!_dbus_user_database_get_groups (user_database, + uid, &group_ids, &n_group_ids, NULL)) + { + _dbus_verbose ("Did not get any groups for UID %lu\n", + uid); + return FALSE; + } + + /* Default to "user owning bus" or root can connect */ + allowed = uid == _dbus_getuid (); + + allowed = list_allows_user (allowed, + &policy->default_rules, + uid, + group_ids, n_group_ids); + + allowed = list_allows_user (allowed, + &policy->mandatory_rules, + uid, + group_ids, n_group_ids); + + dbus_free (group_ids); + + _dbus_verbose ("UID %lu allowed = %d\n", uid, allowed); + + return allowed; +} + +dbus_bool_t +bus_policy_append_default_rule (BusPolicy *policy, + BusPolicyRule *rule) +{ + if (!_dbus_list_append (&policy->default_rules, rule)) + return FALSE; + + bus_policy_rule_ref (rule); + + return TRUE; +} + +dbus_bool_t +bus_policy_append_mandatory_rule (BusPolicy *policy, + BusPolicyRule *rule) +{ + if (!_dbus_list_append (&policy->mandatory_rules, rule)) + return FALSE; + + bus_policy_rule_ref (rule); + + return TRUE; +} + + + +static DBusList** +get_list (DBusHashTable *hash, + unsigned long key) +{ + DBusList **list; + + list = _dbus_hash_table_lookup_ulong (hash, key); + + if (list == NULL) + { + list = dbus_new0 (DBusList*, 1); + if (list == NULL) + return NULL; + + if (!_dbus_hash_table_insert_ulong (hash, key, list)) + { + dbus_free (list); + return NULL; + } + } + + return list; +} + +dbus_bool_t +bus_policy_append_user_rule (BusPolicy *policy, + dbus_uid_t uid, + BusPolicyRule *rule) +{ + DBusList **list; + + list = get_list (policy->rules_by_uid, uid); + + if (list == NULL) + return FALSE; + + if (!_dbus_list_append (list, rule)) + return FALSE; + + bus_policy_rule_ref (rule); + + return TRUE; +} + +dbus_bool_t +bus_policy_append_group_rule (BusPolicy *policy, + dbus_gid_t gid, + BusPolicyRule *rule) +{ + DBusList **list; + + list = get_list (policy->rules_by_gid, gid); + + if (list == NULL) + return FALSE; + + if (!_dbus_list_append (list, rule)) + return FALSE; + + bus_policy_rule_ref (rule); + + return TRUE; +} + +dbus_bool_t +bus_policy_append_console_rule (BusPolicy *policy, + dbus_bool_t at_console, + BusPolicyRule *rule) +{ + if (at_console) + { + if (!_dbus_list_append (&policy->at_console_true_rules, rule)) + return FALSE; + } + else + { + if (!_dbus_list_append (&policy->at_console_false_rules, rule)) + return FALSE; + } + + bus_policy_rule_ref (rule); + + return TRUE; + +} + +static dbus_bool_t +append_copy_of_policy_list (DBusList **list, + DBusList **to_append) +{ + DBusList *link; + DBusList *tmp_list; + + tmp_list = NULL; + + /* Preallocate all our links */ + link = _dbus_list_get_first_link (to_append); + while (link != NULL) + { + if (!_dbus_list_append (&tmp_list, link->data)) + { + _dbus_list_clear (&tmp_list); + return FALSE; + } + + link = _dbus_list_get_next_link (to_append, link); + } + + /* Now append them */ + while ((link = _dbus_list_pop_first_link (&tmp_list))) + { + bus_policy_rule_ref (link->data); + _dbus_list_append_link (list, link); + } + + return TRUE; +} + +static dbus_bool_t +merge_id_hash (DBusHashTable *dest, + DBusHashTable *to_absorb) +{ + DBusHashIter iter; + + _dbus_hash_iter_init (to_absorb, &iter); + while (_dbus_hash_iter_next (&iter)) + { + unsigned long id = _dbus_hash_iter_get_ulong_key (&iter); + DBusList **list = _dbus_hash_iter_get_value (&iter); + DBusList **target = get_list (dest, id); + + if (target == NULL) + return FALSE; + + if (!append_copy_of_policy_list (target, list)) + return FALSE; + } + + return TRUE; +} + +dbus_bool_t +bus_policy_merge (BusPolicy *policy, + BusPolicy *to_absorb) +{ + /* FIXME Not properly atomic, but as used for configuration files we + * don't rely on it quite so much. + */ + + if (!append_copy_of_policy_list (&policy->default_rules, + &to_absorb->default_rules)) + return FALSE; + + if (!append_copy_of_policy_list (&policy->mandatory_rules, + &to_absorb->mandatory_rules)) + return FALSE; + + if (!append_copy_of_policy_list (&policy->at_console_true_rules, + &to_absorb->at_console_true_rules)) + return FALSE; + + if (!append_copy_of_policy_list (&policy->at_console_false_rules, + &to_absorb->at_console_false_rules)) + return FALSE; + + if (!merge_id_hash (policy->rules_by_uid, + to_absorb->rules_by_uid)) + return FALSE; + + if (!merge_id_hash (policy->rules_by_gid, + to_absorb->rules_by_gid)) + return FALSE; + + return TRUE; +} + +struct BusClientPolicy +{ + int refcount; + + DBusList *rules; +}; + +BusClientPolicy* +bus_client_policy_new (void) +{ + BusClientPolicy *policy; + + policy = dbus_new0 (BusClientPolicy, 1); + if (policy == NULL) + return NULL; + + policy->refcount = 1; + + return policy; +} + +BusClientPolicy * +bus_client_policy_ref (BusClientPolicy *policy) +{ + _dbus_assert (policy->refcount > 0); + + policy->refcount += 1; + + return policy; +} + +static void +rule_unref_foreach (void *data, + void *user_data) +{ + BusPolicyRule *rule = data; + + bus_policy_rule_unref (rule); +} + +void +bus_client_policy_unref (BusClientPolicy *policy) +{ + _dbus_assert (policy->refcount > 0); + + policy->refcount -= 1; + + if (policy->refcount == 0) + { + _dbus_list_foreach (&policy->rules, + rule_unref_foreach, + NULL); + + _dbus_list_clear (&policy->rules); + + dbus_free (policy); + } +} + +static void +remove_rules_by_type_up_to (BusClientPolicy *policy, + BusPolicyRuleType type, + DBusList *up_to) +{ + DBusList *link; + + link = _dbus_list_get_first_link (&policy->rules); + while (link != up_to) + { + BusPolicyRule *rule = link->data; + DBusList *next = _dbus_list_get_next_link (&policy->rules, link); + + if (rule->type == type) + { + _dbus_list_remove_link (&policy->rules, link); + bus_policy_rule_unref (rule); + } + + link = next; + } +} + +void +bus_client_policy_optimize (BusClientPolicy *policy) +{ + DBusList *link; + + /* The idea here is that if we have: + * + * + * + * + * (for example) the deny will always override the allow. So we + * delete the allow. Ditto for deny followed by allow, etc. This is + * a dumb thing to put in a config file, but the feature + * of files allows for an "inheritance and override" pattern where + * it could make sense. If an included file wants to "start over" + * with a blanket deny, no point keeping the rules from the parent + * file. + */ + + _dbus_verbose ("Optimizing policy with %d rules\n", + _dbus_list_get_length (&policy->rules)); + + link = _dbus_list_get_first_link (&policy->rules); + while (link != NULL) + { + BusPolicyRule *rule; + DBusList *next; + dbus_bool_t remove_preceding; + + next = _dbus_list_get_next_link (&policy->rules, link); + rule = link->data; + + remove_preceding = FALSE; + + _dbus_assert (rule != NULL); + + switch (rule->type) + { + case BUS_POLICY_RULE_SEND: + remove_preceding = + rule->d.send.message_type == DBUS_MESSAGE_TYPE_INVALID && + rule->d.send.path == NULL && + rule->d.send.interface == NULL && + rule->d.send.member == NULL && + rule->d.send.error == NULL && + rule->d.send.destination == NULL; + break; + case BUS_POLICY_RULE_RECEIVE: + remove_preceding = + rule->d.receive.message_type == DBUS_MESSAGE_TYPE_INVALID && + rule->d.receive.path == NULL && + rule->d.receive.interface == NULL && + rule->d.receive.member == NULL && + rule->d.receive.error == NULL && + rule->d.receive.origin == NULL; + break; + case BUS_POLICY_RULE_OWN: + remove_preceding = + rule->d.own.service_name == NULL; + break; + case BUS_POLICY_RULE_USER: + case BUS_POLICY_RULE_GROUP: + _dbus_assert_not_reached ("invalid rule"); + break; + } + + if (remove_preceding) + remove_rules_by_type_up_to (policy, rule->type, + link); + + link = next; + } + + _dbus_verbose ("After optimization, policy has %d rules\n", + _dbus_list_get_length (&policy->rules)); +} + +dbus_bool_t +bus_client_policy_append_rule (BusClientPolicy *policy, + BusPolicyRule *rule) +{ + _dbus_verbose ("Appending rule %p with type %d to policy %p\n", + rule, rule->type, policy); + + if (!_dbus_list_append (&policy->rules, rule)) + return FALSE; + + bus_policy_rule_ref (rule); + + return TRUE; +} + +dbus_bool_t +bus_client_policy_check_can_send (BusClientPolicy *policy, + BusRegistry *registry, + dbus_bool_t requested_reply, + DBusConnection *receiver, + DBusMessage *message) +{ + DBusList *link; + dbus_bool_t allowed; + + /* policy->rules is in the order the rules appeared + * in the config file, i.e. last rule that applies wins + */ + + _dbus_verbose (" (policy) checking send rules\n"); + + allowed = FALSE; + link = _dbus_list_get_first_link (&policy->rules); + while (link != NULL) + { + BusPolicyRule *rule = link->data; + + link = _dbus_list_get_next_link (&policy->rules, link); + + /* Rule is skipped if it specifies a different + * message name from the message, or a different + * destination from the message + */ + + if (rule->type != BUS_POLICY_RULE_SEND) + { + _dbus_verbose (" (policy) skipping non-send rule\n"); + continue; + } + + if (rule->d.send.message_type != DBUS_MESSAGE_TYPE_INVALID) + { + if (dbus_message_get_type (message) != rule->d.send.message_type) + { + _dbus_verbose (" (policy) skipping rule for different message type\n"); + continue; + } + } + + /* If it's a reply, the requested_reply flag kicks in */ + if (dbus_message_get_reply_serial (message) != 0) + { + /* for allow, requested_reply=true means the rule applies + * only when reply was requested. requested_reply=false means + * always allow. + */ + if (!requested_reply && rule->allow && rule->d.send.requested_reply) + { + _dbus_verbose (" (policy) skipping allow rule since it only applies to requested replies\n"); + continue; + } + + /* for deny, requested_reply=false means the rule applies only + * when the reply was not requested. requested_reply=true means the + * rule always applies. + */ + if (requested_reply && !rule->allow && !rule->d.send.requested_reply) + { + _dbus_verbose (" (policy) skipping deny rule since it only applies to unrequested replies\n"); + continue; + } + } + + if (rule->d.send.path != NULL) + { + if (dbus_message_get_path (message) != NULL && + strcmp (dbus_message_get_path (message), + rule->d.send.path) != 0) + { + _dbus_verbose (" (policy) skipping rule for different path\n"); + continue; + } + } + + if (rule->d.send.interface != NULL) + { + if (dbus_message_get_interface (message) != NULL && + strcmp (dbus_message_get_interface (message), + rule->d.send.interface) != 0) + { + _dbus_verbose (" (policy) skipping rule for different interface\n"); + continue; + } + } + + if (rule->d.send.member != NULL) + { + if (dbus_message_get_member (message) != NULL && + strcmp (dbus_message_get_member (message), + rule->d.send.member) != 0) + { + _dbus_verbose (" (policy) skipping rule for different member\n"); + continue; + } + } + + if (rule->d.send.error != NULL) + { + if (dbus_message_get_error_name (message) != NULL && + strcmp (dbus_message_get_error_name (message), + rule->d.send.error) != 0) + { + _dbus_verbose (" (policy) skipping rule for different error name\n"); + continue; + } + } + + if (rule->d.send.destination != NULL) + { + /* receiver can be NULL for messages that are sent to the + * message bus itself, we check the strings in that case as + * built-in services don't have a DBusConnection but messages + * to them have a destination service name. + */ + if (receiver == NULL) + { + if (!dbus_message_has_destination (message, + rule->d.send.destination)) + { + _dbus_verbose (" (policy) skipping rule because message dest is not %s\n", + rule->d.send.destination); + continue; + } + } + else + { + DBusString str; + BusService *service; + + _dbus_string_init_const (&str, rule->d.send.destination); + + service = bus_registry_lookup (registry, &str); + if (service == NULL) + { + _dbus_verbose (" (policy) skipping rule because dest %s doesn't exist\n", + rule->d.send.destination); + continue; + } + + if (!bus_service_has_owner (service, receiver)) + { + _dbus_verbose (" (policy) skipping rule because dest %s isn't owned by receiver\n", + rule->d.send.destination); + continue; + } + } + } + + /* Use this rule */ + allowed = rule->allow; + + _dbus_verbose (" (policy) used rule, allow now = %d\n", + allowed); + } + + return allowed; +} + +/* See docs on what the args mean on bus_context_check_security_policy() + * comment + */ +dbus_bool_t +bus_client_policy_check_can_receive (BusClientPolicy *policy, + BusRegistry *registry, + dbus_bool_t requested_reply, + DBusConnection *sender, + DBusConnection *addressed_recipient, + DBusConnection *proposed_recipient, + DBusMessage *message) +{ + DBusList *link; + dbus_bool_t allowed; + dbus_bool_t eavesdropping; + + eavesdropping = + addressed_recipient != proposed_recipient && + dbus_message_get_destination (message) != NULL; + + /* policy->rules is in the order the rules appeared + * in the config file, i.e. last rule that applies wins + */ + + _dbus_verbose (" (policy) checking receive rules, eavesdropping = %d\n", eavesdropping); + + allowed = FALSE; + link = _dbus_list_get_first_link (&policy->rules); + while (link != NULL) + { + BusPolicyRule *rule = link->data; + + link = _dbus_list_get_next_link (&policy->rules, link); + + if (rule->type != BUS_POLICY_RULE_RECEIVE) + { + _dbus_verbose (" (policy) skipping non-receive rule\n"); + continue; + } + + if (rule->d.receive.message_type != DBUS_MESSAGE_TYPE_INVALID) + { + if (dbus_message_get_type (message) != rule->d.receive.message_type) + { + _dbus_verbose (" (policy) skipping rule for different message type\n"); + continue; + } + } + + /* for allow, eavesdrop=false means the rule doesn't apply when + * eavesdropping. eavesdrop=true means always allow. + */ + if (eavesdropping && rule->allow && !rule->d.receive.eavesdrop) + { + _dbus_verbose (" (policy) skipping allow rule since it doesn't apply to eavesdropping\n"); + continue; + } + + /* for deny, eavesdrop=true means the rule applies only when + * eavesdropping; eavesdrop=false means always deny. + */ + if (!eavesdropping && !rule->allow && rule->d.receive.eavesdrop) + { + _dbus_verbose (" (policy) skipping deny rule since it only applies to eavesdropping\n"); + continue; + } + + /* If it's a reply, the requested_reply flag kicks in */ + if (dbus_message_get_reply_serial (message) != 0) + { + /* for allow, requested_reply=true means the rule applies + * only when reply was requested. requested_reply=false means + * always allow. + */ + if (!requested_reply && rule->allow && rule->d.receive.requested_reply) + { + _dbus_verbose (" (policy) skipping allow rule since it only applies to requested replies\n"); + continue; + } + + /* for deny, requested_reply=false means the rule applies only + * when the reply was not requested. requested_reply=true means the + * rule always applies. + */ + if (requested_reply && !rule->allow && !rule->d.receive.requested_reply) + { + _dbus_verbose (" (policy) skipping deny rule since it only applies to unrequested replies\n"); + continue; + } + } + + if (rule->d.receive.path != NULL) + { + if (dbus_message_get_path (message) != NULL && + strcmp (dbus_message_get_path (message), + rule->d.receive.path) != 0) + { + _dbus_verbose (" (policy) skipping rule for different path\n"); + continue; + } + } + + if (rule->d.receive.interface != NULL) + { + if (dbus_message_get_interface (message) != NULL && + strcmp (dbus_message_get_interface (message), + rule->d.receive.interface) != 0) + { + _dbus_verbose (" (policy) skipping rule for different interface\n"); + continue; + } + } + + if (rule->d.receive.member != NULL) + { + if (dbus_message_get_member (message) != NULL && + strcmp (dbus_message_get_member (message), + rule->d.receive.member) != 0) + { + _dbus_verbose (" (policy) skipping rule for different member\n"); + continue; + } + } + + if (rule->d.receive.error != NULL) + { + if (dbus_message_get_error_name (message) != NULL && + strcmp (dbus_message_get_error_name (message), + rule->d.receive.error) != 0) + { + _dbus_verbose (" (policy) skipping rule for different error name\n"); + continue; + } + } + + if (rule->d.receive.origin != NULL) + { + /* sender can be NULL for messages that originate from the + * message bus itself, we check the strings in that case as + * built-in services don't have a DBusConnection but will + * still set the sender on their messages. + */ + if (sender == NULL) + { + if (!dbus_message_has_sender (message, + rule->d.receive.origin)) + { + _dbus_verbose (" (policy) skipping rule because message sender is not %s\n", + rule->d.receive.origin); + continue; + } + } + else + { + BusService *service; + DBusString str; + + _dbus_string_init_const (&str, rule->d.receive.origin); + + service = bus_registry_lookup (registry, &str); + + if (service == NULL) + { + _dbus_verbose (" (policy) skipping rule because origin %s doesn't exist\n", + rule->d.receive.origin); + continue; + } + + if (!bus_service_has_owner (service, sender)) + { + _dbus_verbose (" (policy) skipping rule because origin %s isn't owned by sender\n", + rule->d.receive.origin); + continue; + } + } + } + + /* Use this rule */ + allowed = rule->allow; + + _dbus_verbose (" (policy) used rule, allow now = %d\n", + allowed); + } + + return allowed; +} + +dbus_bool_t +bus_client_policy_check_can_own (BusClientPolicy *policy, + DBusConnection *connection, + const DBusString *service_name) +{ + DBusList *link; + dbus_bool_t allowed; + + /* policy->rules is in the order the rules appeared + * in the config file, i.e. last rule that applies wins + */ + + allowed = FALSE; + link = _dbus_list_get_first_link (&policy->rules); + while (link != NULL) + { + BusPolicyRule *rule = link->data; + + link = _dbus_list_get_next_link (&policy->rules, link); + + /* Rule is skipped if it specifies a different service name from + * the desired one. + */ + + if (rule->type != BUS_POLICY_RULE_OWN) + continue; + + if (rule->d.own.service_name != NULL) + { + if (!_dbus_string_equal_c_str (service_name, + rule->d.own.service_name)) + continue; + } + + /* Use this rule */ + allowed = rule->allow; + } + + return allowed; +} + +#ifdef DBUS_BUILD_TESTS + +dbus_bool_t +bus_policy_test (const DBusString *test_data_dir) +{ + /* This doesn't do anything for now because I decided to do it in + * dispatch.c instead by having some of the clients in dispatch.c + * have particular policies applied to them. + */ + + return TRUE; +} + +#endif /* DBUS_BUILD_TESTS */