diff options
author | Luke Shumaker <lukeshu@sbcglobal.net> | 2016-06-12 08:43:34 -0400 |
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committer | Luke Shumaker <lukeshu@sbcglobal.net> | 2016-06-12 08:43:34 -0400 |
commit | 670b77ddfab0f4eddbe539964aba83d446d48129 (patch) | |
tree | 5b159fe9bd52169e05cdc60db5a48a5c5ac9602a /src/libbus-proxy-core/proxy.c | |
parent | 23708daf3ba69ba9880102b4f720a3842883332e (diff) | |
parent | 34dbdee3b2f122d2ef903a368b172e75f962b66a (diff) |
Merge branch 'lukeshu/postmove' into 'lukeshu/master'
Diffstat (limited to 'src/libbus-proxy-core/proxy.c')
-rw-r--r-- | src/libbus-proxy-core/proxy.c | 953 |
1 files changed, 0 insertions, 953 deletions
diff --git a/src/libbus-proxy-core/proxy.c b/src/libbus-proxy-core/proxy.c deleted file mode 100644 index bcfbab0dad..0000000000 --- a/src/libbus-proxy-core/proxy.c +++ /dev/null @@ -1,953 +0,0 @@ -/*** - This file is part of systemd. - - Copyright 2010 Lennart Poettering - Copyright 2013 Daniel Mack - Copyright 2014 Kay Sievers - Copyright 2014 David Herrmann - - systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2.1 of the License, or - (at your option) any later version. - - systemd is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. -***/ - -#include <errno.h> -#include <poll.h> -#include <string.h> -#include <sys/socket.h> -#include <sys/types.h> - -#include <systemd/sd-bus.h> -#include <systemd/sd-daemon.h> - -#include "alloc-util.h" -#include "bus-control.h" -#include "bus-internal.h" -#include "bus-message.h" -#include "bus-util.h" -#include "bus-xml-policy.h" -#include "driver.h" -#include "fd-util.h" -#include "formats-util.h" -#include "log.h" -#include "proxy.h" -#include "set.h" -#include "strv.h" -#include "synthesize.h" -#include "user-util.h" -#include "util.h" - -static int proxy_create_destination(Proxy *p, const char *destination, const char *local_sec, bool negotiate_fds) { - _cleanup_(sd_bus_flush_close_unrefp) sd_bus *b = NULL; - int r; - - r = sd_bus_new(&b); - if (r < 0) - return log_error_errno(r, "Failed to allocate bus: %m"); - - r = sd_bus_set_description(b, "sd-proxy"); - if (r < 0) - return log_error_errno(r, "Failed to set bus name: %m"); - - r = sd_bus_set_address(b, destination); - if (r < 0) - return log_error_errno(r, "Failed to set address to connect to: %m"); - - r = sd_bus_negotiate_fds(b, negotiate_fds); - if (r < 0) - return log_error_errno(r, "Failed to set FD negotiation: %m"); - - r = sd_bus_negotiate_creds(b, true, SD_BUS_CREDS_EUID|SD_BUS_CREDS_PID|SD_BUS_CREDS_EGID|SD_BUS_CREDS_SELINUX_CONTEXT); - if (r < 0) - return log_error_errno(r, "Failed to set credential negotiation: %m"); - - if (p->local_creds.pid > 0) { - b->fake_pids.pid = p->local_creds.pid; - b->fake_pids_valid = true; - - b->fake_creds.uid = UID_INVALID; - b->fake_creds.euid = p->local_creds.uid; - b->fake_creds.suid = UID_INVALID; - b->fake_creds.fsuid = UID_INVALID; - b->fake_creds.gid = GID_INVALID; - b->fake_creds.egid = p->local_creds.gid; - b->fake_creds.sgid = GID_INVALID; - b->fake_creds.fsgid = GID_INVALID; - b->fake_creds_valid = true; - } - - if (local_sec) { - b->fake_label = strdup(local_sec); - if (!b->fake_label) - return log_oom(); - } - - b->manual_peer_interface = true; - - r = sd_bus_start(b); - if (r < 0) - return log_error_errno(r, "Failed to start bus client: %m"); - - p->destination_bus = b; - b = NULL; - return 0; -} - -static int proxy_create_local(Proxy *p, bool negotiate_fds) { - sd_id128_t server_id; - sd_bus *b; - int r; - - r = sd_bus_new(&b); - if (r < 0) - return log_error_errno(r, "Failed to allocate bus: %m"); - - r = sd_bus_set_fd(b, p->local_in, p->local_out); - if (r < 0) { - sd_bus_unref(b); - return log_error_errno(r, "Failed to set fds: %m"); - } - - /* The fds are now owned by the bus, and we indicate that by - * storing the bus object in the proxy object. */ - p->local_bus = b; - - r = sd_bus_get_bus_id(p->destination_bus, &server_id); - if (r < 0) - return log_error_errno(r, "Failed to get server ID: %m"); - - r = sd_bus_set_server(b, 1, server_id); - if (r < 0) - return log_error_errno(r, "Failed to set server mode: %m"); - - r = sd_bus_negotiate_fds(b, negotiate_fds); - if (r < 0) - return log_error_errno(r, "Failed to set FD negotiation: %m"); - - r = sd_bus_negotiate_creds(b, true, SD_BUS_CREDS_EUID|SD_BUS_CREDS_PID|SD_BUS_CREDS_EGID|SD_BUS_CREDS_SELINUX_CONTEXT); - if (r < 0) - return log_error_errno(r, "Failed to set credential negotiation: %m"); - - r = sd_bus_set_anonymous(b, true); - if (r < 0) - return log_error_errno(r, "Failed to set anonymous authentication: %m"); - - b->manual_peer_interface = true; - - r = sd_bus_start(b); - if (r < 0) - return log_error_errno(r, "Failed to start bus client: %m"); - - return 0; -} - -static int proxy_match_synthetic(sd_bus_message *m, void *userdata, sd_bus_error *error) { - Proxy *p = userdata; - - p->synthetic_matched = true; - return 0; /* make sure to continue processing it in further handlers */ -} - -/* - * We always need NameOwnerChanged so we can synthesize NameLost and - * NameAcquired. Furthermore, dbus-1 always passes unicast-signals through, so - * subscribe unconditionally. - */ -static int proxy_prepare_matches(Proxy *p) { - _cleanup_free_ char *match = NULL; - const char *unique; - int r; - - if (!p->destination_bus->is_kernel) - return 0; - - r = sd_bus_get_unique_name(p->destination_bus, &unique); - if (r < 0) - return log_error_errno(r, "Failed to get unique name: %m"); - - match = strjoin("type='signal'," - "sender='org.freedesktop.DBus'," - "path='/org/freedesktop/DBus'," - "interface='org.freedesktop.DBus'," - "member='NameOwnerChanged'," - "arg1='", - unique, - "'", - NULL); - if (!match) - return log_oom(); - - r = sd_bus_add_match(p->destination_bus, NULL, match, proxy_match_synthetic, p); - if (r < 0) - return log_error_errno(r, "Failed to add match for NameLost: %m"); - - free(match); - match = strjoin("type='signal'," - "sender='org.freedesktop.DBus'," - "path='/org/freedesktop/DBus'," - "interface='org.freedesktop.DBus'," - "member='NameOwnerChanged'," - "arg2='", - unique, - "'", - NULL); - if (!match) - return log_oom(); - - r = sd_bus_add_match(p->destination_bus, NULL, match, proxy_match_synthetic, p); - if (r < 0) - return log_error_errno(r, "Failed to add match for NameAcquired: %m"); - - free(match); - match = strjoin("type='signal'," - "destination='", - unique, - "'", - NULL); - if (!match) - return log_oom(); - - r = sd_bus_add_match(p->destination_bus, NULL, match, proxy_match_synthetic, p); - if (r < 0) - log_error_errno(r, "Failed to add match for directed signals: %m"); - /* FIXME: temporarily ignore error to support older kdbus versions */ - - return 0; -} - -int proxy_new(Proxy **out, int in_fd, int out_fd, const char *destination) { - _cleanup_(proxy_freep) Proxy *p = NULL; - _cleanup_free_ char *local_sec = NULL; - bool is_unix; - int r; - - /* This takes possession/destroys the file descriptors passed - * in even on failure. The caller should hence forget about - * the fds in all cases after calling this function and not - * close them. */ - - p = new0(Proxy, 1); - if (!p) { - safe_close(in_fd); - safe_close(out_fd); - return log_oom(); - } - - p->local_in = in_fd; - p->local_out = out_fd; - - p->owned_names = set_new(&string_hash_ops); - if (!p->owned_names) - return log_oom(); - - is_unix = sd_is_socket(in_fd, AF_UNIX, 0, 0) > 0 && - sd_is_socket(out_fd, AF_UNIX, 0, 0) > 0; - - if (is_unix) { - (void) getpeercred(in_fd, &p->local_creds); - (void) getpeersec(in_fd, &local_sec); - } - - r = proxy_create_destination(p, destination, local_sec, is_unix); - if (r < 0) - return r; - - r = proxy_create_local(p, is_unix); - if (r < 0) - return r; - - r = proxy_prepare_matches(p); - if (r < 0) - return r; - - *out = p; - p = NULL; - - return 0; -} - -Proxy *proxy_free(Proxy *p) { - ProxyActivation *activation; - - if (!p) - return NULL; - - while ((activation = p->activations)) { - LIST_REMOVE(activations_by_proxy, p->activations, activation); - sd_bus_message_unref(activation->request); - sd_bus_slot_unref(activation->slot); - free(activation); - } - - if (p->local_bus) - sd_bus_flush_close_unref(p->local_bus); - else { - safe_close(p->local_in); - if (p->local_out != p->local_in) - safe_close(p->local_out); - } - - sd_bus_flush_close_unref(p->destination_bus); - set_free_free(p->owned_names); - free(p); - - return NULL; -} - -int proxy_set_policy(Proxy *p, SharedPolicy *sp, char **configuration) { - _cleanup_strv_free_ char **strv = NULL; - Policy *policy; - int r; - - assert(p); - assert(sp); - - /* no need to load legacy policy if destination is not kdbus */ - if (!p->destination_bus->is_kernel) - return 0; - - p->policy = sp; - - policy = shared_policy_acquire(sp); - if (policy) { - /* policy already pre-loaded */ - shared_policy_release(sp, policy); - return 0; - } - - if (!configuration) { - const char *scope; - - r = sd_bus_get_scope(p->destination_bus, &scope); - if (r < 0) - return log_error_errno(r, "Couldn't determine bus scope: %m"); - - if (streq(scope, "system")) - strv = strv_new("/usr/share/dbus-1/system.conf", - "/etc/dbus-1/system.conf", - "/usr/share/dbus-1/system.d/", - "/etc/dbus-1/system.d/", - "/etc/dbus-1/system-local.conf", - NULL); - else if (streq(scope, "user")) - strv = strv_new("/usr/share/dbus-1/session.conf", - "/etc/dbus-1/session.conf", - "/usr/share/dbus-1/session.d/", - "/etc/dbus-1/session.d/", - "/etc/dbus-1/session-local.conf", - NULL); - else - return log_error("Unknown scope %s, don't know which policy to load. Refusing.", scope); - - if (!strv) - return log_oom(); - - configuration = strv; - } - - return shared_policy_preload(sp, configuration); -} - -int proxy_hello_policy(Proxy *p, uid_t original_uid) { - Policy *policy; - int r = 0; - - assert(p); - - if (!p->policy) - return 0; - - policy = shared_policy_acquire(p->policy); - - if (p->local_creds.uid == original_uid) - log_debug("Permitting access, since bus owner matches bus client."); - else if (policy_check_hello(policy, p->local_creds.uid, p->local_creds.gid)) - log_debug("Permitting access due to XML policy."); - else - r = log_error_errno(EPERM, "Policy denied connection."); - - shared_policy_release(p->policy, policy); - - return r; -} - -static int proxy_wait(Proxy *p) { - uint64_t timeout_destination, timeout_local, t; - int events_destination, events_local, fd; - struct timespec _ts, *ts; - struct pollfd *pollfd; - int r; - - assert(p); - - fd = sd_bus_get_fd(p->destination_bus); - if (fd < 0) - return log_error_errno(fd, "Failed to get fd: %m"); - - events_destination = sd_bus_get_events(p->destination_bus); - if (events_destination < 0) - return log_error_errno(events_destination, "Failed to get events mask: %m"); - - r = sd_bus_get_timeout(p->destination_bus, &timeout_destination); - if (r < 0) - return log_error_errno(r, "Failed to get timeout: %m"); - - events_local = sd_bus_get_events(p->local_bus); - if (events_local < 0) - return log_error_errno(events_local, "Failed to get events mask: %m"); - - r = sd_bus_get_timeout(p->local_bus, &timeout_local); - if (r < 0) - return log_error_errno(r, "Failed to get timeout: %m"); - - t = timeout_destination; - if (t == (uint64_t) -1 || (timeout_local != (uint64_t) -1 && timeout_local < timeout_destination)) - 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_destination, }, - { .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; -} - -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) { - 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; - - /* 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. */ - (void) sd_bus_creds_get_well_known_names(&m->creds, &sender_names); - - (void) sd_bus_creds_get_euid(&m->creds, &sender_uid); - (void) sd_bus_creds_get_egid(&m->creds, &sender_gid); - - if (sender_uid == UID_INVALID || sender_gid == GID_INVALID) { - _cleanup_(sd_bus_creds_unrefp) 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_EUID|SD_BUS_CREDS_EGID, true, &sender_creds); - if (r < 0) - return handle_policy_error(m, r); - - (void) sd_bus_creds_get_euid(sender_creds, &sender_uid); - (void) sd_bus_creds_get_egid(sender_creds, &sender_gid); - } - - /* First check whether the sender can send the message to our name */ - if (policy_check_send(policy, sender_uid, sender_gid, m->header->type, owned_names, NULL, m->path, m->interface, m->member, false, NULL) && - policy_check_recv(policy, our_ucred->uid, our_ucred->gid, m->header->type, NULL, sender_names, 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_(sd_bus_creds_unrefp) 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; - char *n; - - /* 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_EUID|SD_BUS_CREDS_EGID|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); - - (void) sd_bus_creds_get_well_known_names(destination_creds, &destination_names); - - (void) sd_bus_creds_get_euid(destination_creds, &destination_uid); - (void) sd_bus_creds_get_egid(destination_creds, &destination_gid); - } - - /* First check if we (the sender) can send to this name */ - 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 policies that match on receiver - * credentials. We know sd-bus always sets - * KDBUS_MSG_SIGNAL, so the kernel applies policies to - * the message. Therefore, skip policy checks in this - * case. */ - return 0; - } else if (policy_check_send(policy, our_ucred->uid, our_ucred->gid, m->header->type, NULL, destination_names, m->path, m->interface, m->member, true, &n)) { - if (n) { - /* 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) - return r; - } - - if (policy_check_recv(policy, destination_uid, destination_gid, m->header->type, owned_names, NULL, 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; -} - -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; -} - -static int process_hello(Proxy *p, sd_bus_message *m) { - _cleanup_(sd_bus_message_unrefp) 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->destination_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->destination_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->destination_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 = sd_bus_message_set_destination(n, p->destination_bus->unique_name); - if (r < 0) - return log_error_errno(r, "Failed to set destination for 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_destination_to_local(Proxy *p) { - _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL; - bool matched, matched_synthetic; - int r; - - assert(p); - - /* - * Usually, we would just take any message that the bus passes to us - * and forward it to the local connection. However, there are actually - * applications that fail if they receive broadcasts that they didn't - * subscribe to. Therefore, we actually emulate a real broadcast - * matching here, and discard any broadcasts that weren't matched. Our - * match-handlers remembers whether a message was matched by any rule, - * by marking it in @p->message_matched. - */ - - r = sd_bus_process(p->destination_bus, &m); - - matched = p->message_matched; - matched_synthetic = p->synthetic_matched; - p->message_matched = false; - p->synthetic_matched = false; - - if (r == -ECONNRESET || r == -ENOTCONN) /* Treat 'connection reset by peer' as clean exit condition */ - return r; - if (r < 0) { - 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, p->destination_bus, p->local_bus, m); - if (r == -ECONNRESET || r == -ENOTCONN) - return r; - if (r < 0) - return log_error_errno(r, "Failed to synthesize message: %m"); - - /* discard broadcasts that were not matched by any MATCH rule */ - if (!matched && !sd_bus_message_get_destination(m)) { - if (!matched_synthetic) - log_debug("Dropped unmatched broadcast: uid=" UID_FMT " gid=" GID_FMT " pid=" PID_FMT " message=%s path=%s interface=%s member=%s sender=%s destination=%s", - p->local_creds.uid, p->local_creds.gid, p->local_creds.pid, bus_message_type_to_string(m->header->type), - strna(m->path), strna(m->interface), strna(m->member), strna(m->sender), strna(m->destination)); - return 1; - } - - patch_sender(p->destination_bus, m); - - if (p->policy) { - r = process_policy(p->destination_bus, p->local_bus, m, p->policy, &p->local_creds, p->owned_names); - if (r == -ECONNRESET || r == -ENOTCONN) - return r; - if (r < 0) - return log_error_errno(r, "Failed to process policy: %m"); - if (r > 0) - return 1; - } - - r = sd_bus_send(p->local_bus, m, NULL); - if (r < 0) { - if (r == -ECONNRESET || r == -ENOTCONN) - return r; - - /* If the peer tries to send a reply and it is - * rejected with EBADSLT 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 - * EBADSLT 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. */ - - /* FIXME: remove -EPERM when kdbus is updated */ - if ((r == -EPERM || r == -EBADSLT) && m->reply_cookie > 0) - return 1; - - /* Return the error to the client, if we can */ - synthetic_reply_method_errnof(m, r, "Failed to forward message we got from destination: %m"); - if (r == -ENOBUFS) { - /* if local dbus1 peer does not dispatch its queue, warn only once */ - if (!p->queue_overflow) - log_error("Dropped messages due to queue overflow of local peer (pid: "PID_FMT" uid: "UID_FMT")", p->local_creds.pid, p->local_creds.uid); - p->queue_overflow = true; - } else - log_error_errno(r, - "Failed to forward message we got from destination: uid=" UID_FMT " gid=" GID_FMT" message=%s destination=%s path=%s interface=%s member=%s: %m", - p->local_creds.uid, p->local_creds.gid, bus_message_type_to_string(m->header->type), - strna(m->destination), strna(m->path), strna(m->interface), strna(m->member)); - - return 1; - } - - p->queue_overflow = false; - return 1; -} - -static int proxy_process_local_to_destination(Proxy *p) { - _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL; - int r; - - assert(p); - - r = sd_bus_process(p->local_bus, &m); - if (r == -ECONNRESET || r == -ENOTCONN) /* Treat 'connection reset by peer' as clean exit condition */ - return r; - if (r < 0) { - 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 == -ECONNRESET || r == -ENOTCONN) - return r; - if (r < 0) - return log_error_errno(r, "Failed to process HELLO: %m"); - if (r > 0) - return 1; - - r = bus_proxy_process_driver(p, p->destination_bus, p->local_bus, m, p->policy, &p->local_creds, p->owned_names); - if (r == -ECONNRESET || r == -ENOTCONN) - return r; - if (r < 0) - return log_error_errno(r, "Failed to process driver calls: %m"); - if (r > 0) - return 1; - - for (;;) { - if (p->policy) { - r = process_policy(p->local_bus, p->destination_bus, m, p->policy, &p->local_creds, p->owned_names); - if (r == -ECONNRESET || r == -ENOTCONN) - return r; - if (r < 0) - return log_error_errno(r, "Failed to process policy: %m"); - if (r > 0) - return 1; - } - - r = sd_bus_send(p->destination_bus, m, NULL); - if (r < 0) { - if (r == -ECONNRESET || r == -ENOTCONN) - return r; - - /* The name database changed since the policy check, hence let's check again */ - if (r == -EREMCHG) - continue; - - /* see above why EBADSLT is ignored for replies */ - if ((r == -EPERM || r == -EBADSLT) && m->reply_cookie > 0) - return 1; - - synthetic_reply_method_errnof(m, r, "Failed to forward message we got from local: %m"); - log_error_errno(r, - "Failed to forward message we got from local: uid=" UID_FMT " gid=" GID_FMT" message=%s destination=%s path=%s interface=%s member=%s: %m", - p->local_creds.uid, p->local_creds.gid, bus_message_type_to_string(m->header->type), - strna(m->destination), strna(m->path), strna(m->interface), strna(m->member)); - return 1; - } - - break; - } - - return 1; -} - -int proxy_match(sd_bus_message *m, void *userdata, sd_bus_error *error) { - Proxy *p = userdata; - - p->message_matched = true; - return 0; /* make sure to continue processing it in further handlers */ -} - -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_destination_to_local(p); - if (r == -ECONNRESET || r == -ENOTCONN) - return 0; - if (r < 0) - return r; - if (r > 0) - busy = true; - } - - /* Read messages from our client, to pass them on to the bus */ - r = proxy_process_local_to_destination(p); - if (r == -ECONNRESET || r == -ENOTCONN) - return 0; - if (r < 0) - return r; - if (r > 0) - busy = true; - - if (!busy) { - r = proxy_wait(p); - if (r == -ECONNRESET || r == -ENOTCONN) - return 0; - if (r < 0) - return r; - } - } - - return 0; -} |