2015-01-16 14:19:19 +01:00
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/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
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/***
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This file is part of systemd.
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Copyright 2010 Lennart Poettering
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Copyright 2013 Daniel Mack
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Copyright 2014 Kay Sievers
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Copyright 2014 David Herrmann
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systemd is free software; you can redistribute it and/or modify it
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under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 2.1 of the License, or
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(at your option) any later version.
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systemd is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with systemd; If not, see <http://www.gnu.org/licenses/>.
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***/
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#include <sys/socket.h>
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#include <sys/un.h>
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#include <sys/types.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <string.h>
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#include <errno.h>
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#include <sys/poll.h>
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#include <stddef.h>
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#include <getopt.h>
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#include "log.h"
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#include "util.h"
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#include "socket-util.h"
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#include "sd-daemon.h"
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#include "sd-bus.h"
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#include "bus-internal.h"
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#include "bus-message.h"
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#include "bus-util.h"
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#include "build.h"
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#include "strv.h"
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#include "def.h"
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#include "capability.h"
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#include "bus-control.h"
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#include "smack-util.h"
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#include "set.h"
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#include "bus-xml-policy.h"
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#include "driver.h"
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#include "proxy.h"
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#include "synthesize.h"
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static int proxy_create_dest(Proxy *p, const char *dest, const char *local_sec, bool negotiate_fds) {
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_cleanup_bus_close_unref_ sd_bus *b = NULL;
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int r;
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r = sd_bus_new(&b);
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if (r < 0)
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return log_error_errno(r, "Failed to allocate bus: %m");
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r = sd_bus_set_description(b, "sd-proxy");
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if (r < 0)
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return log_error_errno(r, "Failed to set bus name: %m");
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r = sd_bus_set_address(b, dest);
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if (r < 0)
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return log_error_errno(r, "Failed to set address to connect to: %m");
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r = sd_bus_negotiate_fds(b, negotiate_fds);
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if (r < 0)
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return log_error_errno(r, "Failed to set FD negotiation: %m");
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r = sd_bus_negotiate_creds(b, true, SD_BUS_CREDS_UID|SD_BUS_CREDS_PID|SD_BUS_CREDS_GID|SD_BUS_CREDS_SELINUX_CONTEXT);
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if (r < 0)
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return log_error_errno(r, "Failed to set credential negotiation: %m");
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if (p->local_creds.pid > 0) {
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b->fake_pids.pid = p->local_creds.pid;
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b->fake_pids_valid = true;
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b->fake_creds.uid = p->local_creds.uid;
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b->fake_creds.euid = UID_INVALID;
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b->fake_creds.suid = UID_INVALID;
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b->fake_creds.fsuid = UID_INVALID;
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b->fake_creds.gid = p->local_creds.gid;
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b->fake_creds.egid = GID_INVALID;
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b->fake_creds.sgid = GID_INVALID;
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b->fake_creds.fsgid = GID_INVALID;
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b->fake_creds_valid = true;
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}
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if (local_sec) {
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b->fake_label = strdup(local_sec);
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if (!b->fake_label)
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return log_oom();
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}
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b->manual_peer_interface = true;
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r = sd_bus_start(b);
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if (r < 0)
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return log_error_errno(r, "Failed to start bus client: %m");
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p->dest_bus = b;
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b = NULL;
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return 0;
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}
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static int proxy_create_local(Proxy *p, int in_fd, int out_fd, bool negotiate_fds) {
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_cleanup_bus_close_unref_ sd_bus *b = NULL;
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sd_id128_t server_id;
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int r;
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r = sd_bus_new(&b);
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if (r < 0)
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return log_error_errno(r, "Failed to allocate bus: %m");
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r = sd_bus_set_fd(b, in_fd, out_fd);
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if (r < 0)
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return log_error_errno(r, "Failed to set fds: %m");
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r = sd_bus_get_bus_id(p->dest_bus, &server_id);
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if (r < 0)
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return log_error_errno(r, "Failed to get server ID: %m");
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r = sd_bus_set_server(b, 1, server_id);
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if (r < 0)
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return log_error_errno(r, "Failed to set server mode: %m");
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r = sd_bus_negotiate_fds(b, negotiate_fds);
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if (r < 0)
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return log_error_errno(r, "Failed to set FD negotiation: %m");
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r = sd_bus_negotiate_creds(b, true, SD_BUS_CREDS_UID|SD_BUS_CREDS_PID|SD_BUS_CREDS_GID|SD_BUS_CREDS_SELINUX_CONTEXT);
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if (r < 0)
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return log_error_errno(r, "Failed to set credential negotiation: %m");
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r = sd_bus_set_anonymous(b, true);
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if (r < 0)
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return log_error_errno(r, "Failed to set anonymous authentication: %m");
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b->manual_peer_interface = true;
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r = sd_bus_start(b);
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if (r < 0)
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return log_error_errno(r, "Failed to start bus client: %m");
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p->local_bus = b;
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b = NULL;
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return 0;
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}
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static int proxy_prepare_matches(Proxy *p) {
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_cleanup_free_ char *match = NULL;
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const char *unique;
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int r;
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if (!p->dest_bus->is_kernel)
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return 0;
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r = sd_bus_get_unique_name(p->dest_bus, &unique);
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if (r < 0)
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return log_error_errno(r, "Failed to get unique name: %m");
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match = strjoin("type='signal',"
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"sender='org.freedesktop.DBus',"
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"path='/org/freedesktop/DBus',"
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"interface='org.freedesktop.DBus',"
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"member='NameOwnerChanged',"
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"arg1='",
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unique,
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"'",
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NULL);
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if (!match)
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return log_oom();
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r = sd_bus_add_match(p->dest_bus, NULL, match, NULL, NULL);
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if (r < 0)
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return log_error_errno(r, "Failed to add match for NameLost: %m");
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free(match);
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match = strjoin("type='signal',"
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"sender='org.freedesktop.DBus',"
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"path='/org/freedesktop/DBus',"
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"interface='org.freedesktop.DBus',"
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"member='NameOwnerChanged',"
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"arg2='",
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unique,
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"'",
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NULL);
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if (!match)
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return log_oom();
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r = sd_bus_add_match(p->dest_bus, NULL, match, NULL, NULL);
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if (r < 0)
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return log_error_errno(r, "Failed to add match for NameAcquired: %m");
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return 0;
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}
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int proxy_new(Proxy **out, int in_fd, int out_fd, const char *dest) {
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_cleanup_(proxy_freep) Proxy *p = NULL;
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_cleanup_free_ char *local_sec = NULL;
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bool is_unix;
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int r;
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p = new0(Proxy, 1);
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if (!p)
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return log_oom();
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p->local_in = in_fd;
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p->local_out = out_fd;
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p->owned_names = set_new(&string_hash_ops);
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if (!p->owned_names)
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return log_oom();
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is_unix = sd_is_socket(in_fd, AF_UNIX, 0, 0) > 0 &&
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sd_is_socket(out_fd, AF_UNIX, 0, 0) > 0;
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if (is_unix) {
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(void) getpeercred(in_fd, &p->local_creds);
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(void) getpeersec(in_fd, &local_sec);
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}
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r = proxy_create_dest(p, dest, local_sec, is_unix);
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if (r < 0)
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return r;
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r = proxy_create_local(p, in_fd, out_fd, is_unix);
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if (r < 0)
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return r;
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r = proxy_prepare_matches(p);
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if (r < 0)
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return r;
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*out = p;
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p = NULL;
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return 0;
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}
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Proxy *proxy_free(Proxy *p) {
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if (!p)
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return NULL;
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sd_bus_close_unrefp(&p->local_bus);
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sd_bus_close_unrefp(&p->dest_bus);
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set_free_free(p->owned_names);
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free(p);
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return NULL;
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}
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2015-01-17 18:07:58 +01:00
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int proxy_set_policy(Proxy *p, SharedPolicy *sp, char **configuration) {
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2015-01-16 14:19:19 +01:00
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_cleanup_strv_free_ char **strv = NULL;
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2015-01-17 18:07:58 +01:00
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Policy *policy;
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2015-01-16 14:19:19 +01:00
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int r;
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assert(p);
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2015-01-17 18:07:58 +01:00
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assert(sp);
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2015-01-16 14:19:19 +01:00
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/* no need to load legacy policy if destination is not kdbus */
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if (!p->dest_bus->is_kernel)
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return 0;
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2015-01-17 18:07:58 +01:00
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p->policy = sp;
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policy = shared_policy_acquire(sp);
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if (policy) {
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/* policy already pre-loaded */
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shared_policy_release(sp, policy);
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return 0;
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}
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2015-01-16 14:19:19 +01:00
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if (!configuration) {
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const char *scope;
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r = sd_bus_get_scope(p->dest_bus, &scope);
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if (r < 0)
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return log_error_errno(r, "Couldn't determine bus scope: %m");
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if (streq(scope, "system"))
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strv = strv_new("/etc/dbus-1/system.conf",
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"/etc/dbus-1/system.d/",
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"/etc/dbus-1/system-local.conf",
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NULL);
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else if (streq(scope, "user"))
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strv = strv_new("/etc/dbus-1/session.conf",
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"/etc/dbus-1/session.d/",
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"/etc/dbus-1/session-local.conf",
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NULL);
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else
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return log_error("Unknown scope %s, don't know which policy to load. Refusing.", scope);
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if (!strv)
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return log_oom();
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configuration = strv;
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}
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2015-01-17 18:07:58 +01:00
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return shared_policy_preload(sp, configuration);
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2015-01-16 14:19:19 +01:00
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}
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int proxy_hello_policy(Proxy *p, uid_t original_uid) {
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Policy *policy;
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int r = 0;
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2015-01-16 14:19:19 +01:00
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assert(p);
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if (!p->policy)
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return 0;
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2015-01-17 18:07:58 +01:00
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policy = shared_policy_acquire(p->policy);
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2015-01-16 14:19:19 +01:00
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if (p->local_creds.uid == original_uid)
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log_debug("Permitting access, since bus owner matches bus client.");
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2015-01-17 18:07:58 +01:00
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else if (policy_check_hello(policy, p->local_creds.uid, p->local_creds.gid))
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2015-01-16 14:19:19 +01:00
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log_debug("Permitting access due to XML policy.");
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else
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2015-01-17 18:07:58 +01:00
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r = log_error_errno(EPERM, "Policy denied connection.");
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2015-01-16 14:19:19 +01:00
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2015-01-17 18:07:58 +01:00
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shared_policy_release(p->policy, policy);
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return r;
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2015-01-16 14:19:19 +01:00
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}
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static int proxy_wait(Proxy *p) {
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uint64_t timeout_dest, timeout_local, t;
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int events_dest, events_local, fd;
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struct timespec _ts, *ts;
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struct pollfd *pollfd;
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int r;
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assert(p);
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fd = sd_bus_get_fd(p->dest_bus);
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if (fd < 0)
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return log_error_errno(fd, "Failed to get fd: %m");
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events_dest = sd_bus_get_events(p->dest_bus);
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if (events_dest < 0)
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return log_error_errno(events_dest, "Failed to get events mask: %m");
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r = sd_bus_get_timeout(p->dest_bus, &timeout_dest);
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if (r < 0)
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return log_error_errno(r, "Failed to get timeout: %m");
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events_local = sd_bus_get_events(p->local_bus);
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if (events_local < 0)
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return log_error_errno(events_local, "Failed to get events mask: %m");
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r = sd_bus_get_timeout(p->local_bus, &timeout_local);
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if (r < 0)
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|
return log_error_errno(r, "Failed to get timeout: %m");
|
|
|
|
|
|
|
|
t = timeout_dest;
|
|
|
|
if (t == (uint64_t) -1 || (timeout_local != (uint64_t) -1 && timeout_local < timeout_dest))
|
|
|
|
t = timeout_local;
|
|
|
|
|
|
|
|
if (t == (uint64_t) -1)
|
|
|
|
ts = NULL;
|
|
|
|
else {
|
|
|
|
usec_t nw;
|
|
|
|
|
|
|
|
nw = now(CLOCK_MONOTONIC);
|
|
|
|
if (t > nw)
|
|
|
|
t -= nw;
|
|
|
|
else
|
|
|
|
t = 0;
|
|
|
|
|
|
|
|
ts = timespec_store(&_ts, t);
|
|
|
|
}
|
|
|
|
|
|
|
|
pollfd = (struct pollfd[3]) {
|
|
|
|
{ .fd = fd, .events = events_dest, },
|
|
|
|
{ .fd = p->local_in, .events = events_local & POLLIN, },
|
|
|
|
{ .fd = p->local_out, .events = events_local & POLLOUT, },
|
|
|
|
};
|
|
|
|
|
|
|
|
r = ppoll(pollfd, 3, ts, NULL);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(errno, "ppoll() failed: %m");
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int handle_policy_error(sd_bus_message *m, int r) {
|
|
|
|
if (r == -ESRCH || r == -ENXIO)
|
|
|
|
return synthetic_reply_method_errorf(m, SD_BUS_ERROR_NAME_HAS_NO_OWNER, "Name %s is currently not owned by anyone.", m->destination);
|
|
|
|
|
|
|
|
return r;
|
|
|
|
}
|
|
|
|
|
2015-01-17 18:07:58 +01:00
|
|
|
static int process_policy_unlocked(sd_bus *from, sd_bus *to, sd_bus_message *m, Policy *policy, const struct ucred *our_ucred, Set *owned_names) {
|
2015-01-16 14:19:19 +01:00
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(from);
|
|
|
|
assert(to);
|
|
|
|
assert(m);
|
|
|
|
|
|
|
|
if (!policy)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* dbus-1 distinguishes expected and non-expected replies by tracking
|
|
|
|
* method-calls and timeouts. By default, DENY rules are *NEVER* applied
|
|
|
|
* on expected replies, unless explicitly specified. But we dont track
|
|
|
|
* method-calls, thus, we cannot know whether a reply is expected.
|
|
|
|
* Fortunately, the kdbus forbids non-expected replies, so we can safely
|
|
|
|
* ignore any policy on those and let the kernel deal with it.
|
|
|
|
*
|
|
|
|
* TODO: To be correct, we should only ignore policy-tags that are
|
|
|
|
* applied on non-expected replies. However, so far we don't parse those
|
|
|
|
* tags so we let everything pass. I haven't seen a DENY policy tag on
|
|
|
|
* expected-replies, ever, so don't bother..
|
|
|
|
*/
|
|
|
|
if (m->reply_cookie > 0)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
if (from->is_kernel) {
|
|
|
|
uid_t sender_uid = UID_INVALID;
|
|
|
|
gid_t sender_gid = GID_INVALID;
|
|
|
|
char **sender_names = NULL;
|
|
|
|
bool granted = false;
|
|
|
|
|
|
|
|
/* Driver messages are always OK */
|
|
|
|
if (streq_ptr(m->sender, "org.freedesktop.DBus"))
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
/* The message came from the kernel, and is sent to our legacy client. */
|
|
|
|
sd_bus_creds_get_well_known_names(&m->creds, &sender_names);
|
|
|
|
|
|
|
|
(void) sd_bus_creds_get_uid(&m->creds, &sender_uid);
|
|
|
|
(void) sd_bus_creds_get_gid(&m->creds, &sender_gid);
|
|
|
|
|
|
|
|
if (sender_uid == UID_INVALID || sender_gid == GID_INVALID) {
|
|
|
|
_cleanup_bus_creds_unref_ sd_bus_creds *sender_creds = NULL;
|
|
|
|
|
|
|
|
/* If the message came from another legacy
|
|
|
|
* client, then the message creds will be
|
|
|
|
* missing, simply because on legacy clients
|
|
|
|
* per-message creds were unknown. In this
|
|
|
|
* case, query the creds of the peer
|
|
|
|
* instead. */
|
|
|
|
|
|
|
|
r = bus_get_name_creds_kdbus(from, m->sender, SD_BUS_CREDS_UID|SD_BUS_CREDS_GID, true, &sender_creds);
|
|
|
|
if (r < 0)
|
|
|
|
return handle_policy_error(m, r);
|
|
|
|
|
|
|
|
(void) sd_bus_creds_get_uid(sender_creds, &sender_uid);
|
|
|
|
(void) sd_bus_creds_get_gid(sender_creds, &sender_gid);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* First check whether the sender can send the message to our name */
|
|
|
|
if (set_isempty(owned_names)) {
|
|
|
|
if (policy_check_send(policy, sender_uid, sender_gid, m->header->type, NULL, m->path, m->interface, m->member, false))
|
|
|
|
granted = true;
|
|
|
|
} else {
|
|
|
|
Iterator i;
|
|
|
|
char *n;
|
|
|
|
|
|
|
|
SET_FOREACH(n, owned_names, i)
|
|
|
|
if (policy_check_send(policy, sender_uid, sender_gid, m->header->type, n, m->path, m->interface, m->member, false)) {
|
|
|
|
granted = true;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
if (granted) {
|
|
|
|
/* Then check whether us (the recipient) can receive from the sender's name */
|
|
|
|
if (strv_isempty(sender_names)) {
|
|
|
|
if (policy_check_recv(policy, our_ucred->uid, our_ucred->gid, m->header->type, NULL, m->path, m->interface, m->member, false))
|
|
|
|
return 0;
|
|
|
|
} else {
|
|
|
|
char **n;
|
|
|
|
|
|
|
|
STRV_FOREACH(n, sender_names) {
|
|
|
|
if (policy_check_recv(policy, our_ucred->uid, our_ucred->gid, m->header->type, *n, m->path, m->interface, m->member, false))
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Return an error back to the caller */
|
|
|
|
if (m->header->type == SD_BUS_MESSAGE_METHOD_CALL)
|
|
|
|
return synthetic_reply_method_errorf(m, SD_BUS_ERROR_ACCESS_DENIED, "Access prohibited by XML receiver policy.");
|
|
|
|
|
|
|
|
/* Return 1, indicating that the message shall not be processed any further */
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (to->is_kernel) {
|
|
|
|
_cleanup_bus_creds_unref_ sd_bus_creds *destination_creds = NULL;
|
|
|
|
uid_t destination_uid = UID_INVALID;
|
|
|
|
gid_t destination_gid = GID_INVALID;
|
|
|
|
const char *destination_unique = NULL;
|
|
|
|
char **destination_names = NULL;
|
|
|
|
bool granted = false;
|
|
|
|
|
|
|
|
/* Driver messages are always OK */
|
|
|
|
if (streq_ptr(m->destination, "org.freedesktop.DBus"))
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
/* The message came from the legacy client, and is sent to kdbus. */
|
|
|
|
if (m->destination) {
|
|
|
|
r = bus_get_name_creds_kdbus(to, m->destination,
|
|
|
|
SD_BUS_CREDS_WELL_KNOWN_NAMES|SD_BUS_CREDS_UNIQUE_NAME|
|
|
|
|
SD_BUS_CREDS_UID|SD_BUS_CREDS_GID|SD_BUS_CREDS_PID,
|
|
|
|
true, &destination_creds);
|
|
|
|
if (r < 0)
|
|
|
|
return handle_policy_error(m, r);
|
|
|
|
|
|
|
|
r = sd_bus_creds_get_unique_name(destination_creds, &destination_unique);
|
|
|
|
if (r < 0)
|
|
|
|
return handle_policy_error(m, r);
|
|
|
|
|
|
|
|
sd_bus_creds_get_well_known_names(destination_creds, &destination_names);
|
|
|
|
|
|
|
|
(void) sd_bus_creds_get_uid(destination_creds, &destination_uid);
|
|
|
|
(void) sd_bus_creds_get_gid(destination_creds, &destination_gid);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* First check if we (the sender) can send to this name */
|
|
|
|
if (strv_isempty(destination_names)) {
|
|
|
|
if (policy_check_send(policy, our_ucred->uid, our_ucred->gid, m->header->type, NULL, m->path, m->interface, m->member, true))
|
|
|
|
granted = true;
|
|
|
|
} else {
|
|
|
|
char **n;
|
|
|
|
|
|
|
|
STRV_FOREACH(n, destination_names) {
|
|
|
|
if (policy_check_send(policy, our_ucred->uid, our_ucred->gid, m->header->type, *n, m->path, m->interface, m->member, true)) {
|
|
|
|
|
|
|
|
/* If we made a receiver decision,
|
|
|
|
then remember which name's policy
|
|
|
|
we used, and to which unique ID it
|
|
|
|
mapped when we made the
|
|
|
|
decision. Then, let's pass this to
|
|
|
|
the kernel when sending the
|
|
|
|
message, so that it refuses the
|
|
|
|
operation should the name and
|
|
|
|
unique ID not map to each other
|
|
|
|
anymore. */
|
|
|
|
|
|
|
|
r = free_and_strdup(&m->destination_ptr, *n);
|
|
|
|
if (r < 0)
|
|
|
|
return r;
|
|
|
|
|
|
|
|
r = bus_kernel_parse_unique_name(destination_unique, &m->verify_destination_id);
|
|
|
|
if (r < 0)
|
|
|
|
break;
|
|
|
|
|
|
|
|
granted = true;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Then check if the recipient can receive from our name */
|
|
|
|
if (granted) {
|
|
|
|
if (sd_bus_message_is_signal(m, NULL, NULL)) {
|
|
|
|
/* If we forward a signal from dbus-1 to kdbus,
|
|
|
|
* we have no idea who the recipient is.
|
|
|
|
* Therefore, we cannot apply any dbus-1
|
|
|
|
* receiver policies that match on receiver
|
|
|
|
* credentials. We know sd-bus always sets
|
|
|
|
* KDBUS_MSG_SIGNAL, so the kernel applies
|
|
|
|
* receiver policies to the message. Therefore,
|
|
|
|
* skip policy checks in this case. */
|
|
|
|
return 0;
|
|
|
|
} else if (set_isempty(owned_names)) {
|
|
|
|
if (policy_check_recv(policy, destination_uid, destination_gid, m->header->type, NULL, m->path, m->interface, m->member, true))
|
|
|
|
return 0;
|
|
|
|
} else {
|
|
|
|
Iterator i;
|
|
|
|
char *n;
|
|
|
|
|
|
|
|
SET_FOREACH(n, owned_names, i)
|
|
|
|
if (policy_check_recv(policy, destination_uid, destination_gid, m->header->type, n, m->path, m->interface, m->member, true))
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Return an error back to the caller */
|
|
|
|
if (m->header->type == SD_BUS_MESSAGE_METHOD_CALL)
|
|
|
|
return synthetic_reply_method_errorf(m, SD_BUS_ERROR_ACCESS_DENIED, "Access prohibited by XML sender policy.");
|
|
|
|
|
|
|
|
/* Return 1, indicating that the message shall not be processed any further */
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2015-01-17 18:07:58 +01:00
|
|
|
static int process_policy(sd_bus *from, sd_bus *to, sd_bus_message *m, SharedPolicy *sp, const struct ucred *our_ucred, Set *owned_names) {
|
|
|
|
Policy *policy;
|
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(sp);
|
|
|
|
|
|
|
|
policy = shared_policy_acquire(sp);
|
|
|
|
r = process_policy_unlocked(from, to, m, policy, our_ucred, owned_names);
|
|
|
|
shared_policy_release(sp, policy);
|
|
|
|
|
|
|
|
return r;
|
|
|
|
}
|
|
|
|
|
2015-01-16 14:19:19 +01:00
|
|
|
static int process_hello(Proxy *p, sd_bus_message *m) {
|
|
|
|
_cleanup_bus_message_unref_ sd_bus_message *n = NULL;
|
|
|
|
bool is_hello;
|
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(p);
|
|
|
|
assert(m);
|
|
|
|
|
|
|
|
/* As reaction to hello we need to respond with two messages:
|
|
|
|
* the callback reply and the NameAcquired for the unique
|
|
|
|
* name, since hello is otherwise obsolete on kdbus. */
|
|
|
|
|
|
|
|
is_hello =
|
|
|
|
sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "Hello") &&
|
|
|
|
streq_ptr(m->destination, "org.freedesktop.DBus");
|
|
|
|
|
|
|
|
if (!is_hello) {
|
|
|
|
if (p->got_hello)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
return log_error_errno(-EIO, "First packet isn't hello (it's %s.%s), aborting.", m->interface, m->member);
|
|
|
|
}
|
|
|
|
|
|
|
|
if (p->got_hello)
|
|
|
|
return log_error_errno(-EIO, "Got duplicate hello, aborting.");
|
|
|
|
|
|
|
|
p->got_hello = true;
|
|
|
|
|
|
|
|
if (!p->dest_bus->is_kernel)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
r = sd_bus_message_new_method_return(m, &n);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to generate HELLO reply: %m");
|
|
|
|
|
|
|
|
r = sd_bus_message_append(n, "s", p->dest_bus->unique_name);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to append unique name to HELLO reply: %m");
|
|
|
|
|
|
|
|
r = bus_message_append_sender(n, "org.freedesktop.DBus");
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to append sender to HELLO reply: %m");
|
|
|
|
|
|
|
|
r = bus_seal_synthetic_message(p->local_bus, n);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to seal HELLO reply: %m");
|
|
|
|
|
|
|
|
r = sd_bus_send(p->local_bus, n, NULL);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to send HELLO reply: %m");
|
|
|
|
|
|
|
|
n = sd_bus_message_unref(n);
|
|
|
|
r = sd_bus_message_new_signal(
|
|
|
|
p->local_bus,
|
|
|
|
&n,
|
|
|
|
"/org/freedesktop/DBus",
|
|
|
|
"org.freedesktop.DBus",
|
|
|
|
"NameAcquired");
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to allocate initial NameAcquired message: %m");
|
|
|
|
|
|
|
|
r = sd_bus_message_append(n, "s", p->dest_bus->unique_name);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to append unique name to NameAcquired message: %m");
|
|
|
|
|
|
|
|
r = bus_message_append_sender(n, "org.freedesktop.DBus");
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to append sender to NameAcquired message: %m");
|
|
|
|
|
|
|
|
r = bus_seal_synthetic_message(p->local_bus, n);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to seal NameAcquired message: %m");
|
|
|
|
|
|
|
|
r = sd_bus_send(p->local_bus, n, NULL);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to send NameAcquired message: %m");
|
|
|
|
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int patch_sender(sd_bus *a, sd_bus_message *m) {
|
|
|
|
char **well_known = NULL;
|
|
|
|
sd_bus_creds *c;
|
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(a);
|
|
|
|
assert(m);
|
|
|
|
|
|
|
|
if (!a->is_kernel)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
/* We will change the sender of messages from the bus driver
|
|
|
|
* so that they originate from the bus driver. This is a
|
|
|
|
* speciality originating from dbus1, where the bus driver did
|
|
|
|
* not have a unique id, but only the well-known name. */
|
|
|
|
|
|
|
|
c = sd_bus_message_get_creds(m);
|
|
|
|
if (!c)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
r = sd_bus_creds_get_well_known_names(c, &well_known);
|
|
|
|
if (r < 0)
|
|
|
|
return r;
|
|
|
|
|
|
|
|
if (strv_contains(well_known, "org.freedesktop.DBus"))
|
|
|
|
m->sender = "org.freedesktop.DBus";
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int proxy_process_dest_to_local(Proxy *p) {
|
|
|
|
_cleanup_bus_message_unref_ sd_bus_message *m = NULL;
|
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(p);
|
|
|
|
|
|
|
|
r = sd_bus_process(p->dest_bus, &m);
|
|
|
|
if (r < 0) {
|
|
|
|
/* treat 'connection reset by peer' as clean exit condition */
|
|
|
|
if (r != -ECONNRESET)
|
|
|
|
log_error_errno(r, "Failed to process destination bus: %m");
|
|
|
|
return r;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (r == 0)
|
|
|
|
return 0;
|
|
|
|
if (!m)
|
|
|
|
return 1;
|
|
|
|
|
|
|
|
/* We officially got EOF, let's quit */
|
|
|
|
if (sd_bus_message_is_signal(m, "org.freedesktop.DBus.Local", "Disconnected"))
|
|
|
|
return -ECONNRESET;
|
|
|
|
|
|
|
|
r = synthesize_name_acquired(p->dest_bus, p->local_bus, m);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to synthesize message: %m");
|
|
|
|
|
|
|
|
patch_sender(p->dest_bus, m);
|
|
|
|
|
|
|
|
if (p->policy) {
|
|
|
|
r = process_policy(p->dest_bus, p->local_bus, m, p->policy, &p->local_creds, p->owned_names);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to process policy: %m");
|
|
|
|
else if (r > 0)
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
r = sd_bus_send(p->local_bus, m, NULL);
|
|
|
|
if (r < 0) {
|
|
|
|
if (r == -EPERM && m->reply_cookie > 0) {
|
|
|
|
/* If the peer tries to send a reply and it is rejected with EPERM
|
|
|
|
* by the kernel, we ignore the error. This catches cases where the
|
|
|
|
* original method-call didn't had EXPECT_REPLY set, but the proxy-peer
|
|
|
|
* still sends a reply. This is allowed in dbus1, but not in kdbus. We
|
|
|
|
* don't want to track reply-windows in the proxy, so we simply ignore
|
|
|
|
* EPERM for all replies. The only downside is, that callers are no
|
|
|
|
* longer notified if their replies are dropped. However, this is
|
|
|
|
* equivalent to the caller's timeout to expire, so this should be
|
|
|
|
* acceptable. Nobody sane sends replies without a matching method-call,
|
|
|
|
* so nobody should care. */
|
|
|
|
return 1;
|
|
|
|
} else {
|
|
|
|
if (r != -ECONNRESET)
|
|
|
|
log_error_errno(r, "Failed to send message to client: %m");
|
|
|
|
return r;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int proxy_process_local_to_dest(Proxy *p) {
|
|
|
|
_cleanup_bus_message_unref_ sd_bus_message *m = NULL;
|
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(p);
|
|
|
|
|
|
|
|
r = sd_bus_process(p->local_bus, &m);
|
|
|
|
if (r < 0) {
|
|
|
|
/* treat 'connection reset by peer' as clean exit condition */
|
|
|
|
if (r != -ECONNRESET)
|
|
|
|
log_error_errno(r, "Failed to process local bus: %m");
|
|
|
|
return r;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (r == 0)
|
|
|
|
return 0;
|
|
|
|
if (!m)
|
|
|
|
return 1;
|
|
|
|
|
|
|
|
/* We officially got EOF, let's quit */
|
|
|
|
if (sd_bus_message_is_signal(m, "org.freedesktop.DBus.Local", "Disconnected"))
|
|
|
|
return -ECONNRESET;
|
|
|
|
|
|
|
|
r = process_hello(p, m);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to process HELLO: %m");
|
|
|
|
else if (r > 0)
|
|
|
|
return 1;
|
|
|
|
|
|
|
|
r = bus_proxy_process_driver(p->dest_bus, p->local_bus, m, p->policy, &p->local_creds, p->owned_names);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to process driver calls: %m");
|
|
|
|
else if (r > 0)
|
|
|
|
return 1;
|
|
|
|
|
|
|
|
for (;;) {
|
|
|
|
if (p->policy) {
|
|
|
|
r = process_policy(p->local_bus, p->dest_bus, m, p->policy, &p->local_creds, p->owned_names);
|
|
|
|
if (r < 0)
|
|
|
|
return log_error_errno(r, "Failed to process policy: %m");
|
|
|
|
else if (r > 0)
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
r = sd_bus_send(p->dest_bus, m, NULL);
|
|
|
|
if (r < 0) {
|
|
|
|
if (r == -EREMCHG) {
|
|
|
|
/* The name database changed since the policy check, hence let's check again */
|
|
|
|
continue;
|
|
|
|
} else if (r == -EPERM && m->reply_cookie > 0) {
|
|
|
|
/* see above why EPERM is ignored for replies */
|
|
|
|
return 1;
|
|
|
|
} else {
|
|
|
|
if (r != -ECONNRESET)
|
|
|
|
log_error_errno(r, "Failed to send message to bus: %m");
|
|
|
|
return r;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
int proxy_run(Proxy *p) {
|
|
|
|
int r;
|
|
|
|
|
|
|
|
assert(p);
|
|
|
|
|
|
|
|
for (;;) {
|
|
|
|
bool busy = false;
|
|
|
|
|
|
|
|
if (p->got_hello) {
|
|
|
|
/* Read messages from bus, to pass them on to our client */
|
|
|
|
r = proxy_process_dest_to_local(p);
|
|
|
|
if (r == -ECONNRESET)
|
|
|
|
return 0;
|
|
|
|
else if (r < 0)
|
|
|
|
return r;
|
|
|
|
else if (r > 0)
|
|
|
|
busy = true;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Read messages from our client, to pass them on to the bus */
|
|
|
|
r = proxy_process_local_to_dest(p);
|
|
|
|
if (r == -ECONNRESET)
|
|
|
|
return 0;
|
|
|
|
else if (r < 0)
|
|
|
|
return r;
|
|
|
|
else if (r > 0)
|
|
|
|
busy = true;
|
|
|
|
|
|
|
|
if (!busy) {
|
|
|
|
r = proxy_wait(p);
|
|
|
|
if (r < 0)
|
|
|
|
return r;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|