1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2013 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
22 #ifdef HAVE_VALGRIND_MEMCHECK_H
23 #include <valgrind/memcheck.h>
30 #include <sys/prctl.h>
34 #include "memfd-util.h"
36 #include "bus-internal.h"
37 #include "bus-message.h"
38 #include "bus-kernel.h"
39 #include "bus-bloom.h"
41 #include "bus-label.h"
42 #include "cgroup-util.h"
44 #define UNIQUE_NAME_MAX (3+DECIMAL_STR_MAX(uint64_t))
46 int bus_kernel_parse_unique_name(const char *s, uint64_t *id) {
52 if (!startswith(s, ":1."))
55 r = safe_atou64(s + 3, id);
62 static void append_payload_vec(struct kdbus_item **d, const void *p, size_t sz) {
68 /* Note that p can be NULL, which encodes a region full of
69 * zeroes, which is useful to optimize certain padding
72 (*d)->size = offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec);
73 (*d)->type = KDBUS_ITEM_PAYLOAD_VEC;
74 (*d)->vec.address = PTR_TO_UINT64(p);
77 *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size);
80 static void append_payload_memfd(struct kdbus_item **d, int memfd, size_t sz) {
86 (*d)->size = offsetof(struct kdbus_item, memfd) + sizeof(struct kdbus_memfd);
87 (*d)->type = KDBUS_ITEM_PAYLOAD_MEMFD;
88 (*d)->memfd.fd = memfd;
89 (*d)->memfd.size = sz;
91 *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size);
94 static void append_destination(struct kdbus_item **d, const char *s, size_t length) {
100 (*d)->size = offsetof(struct kdbus_item, str) + length + 1;
101 (*d)->type = KDBUS_ITEM_DST_NAME;
102 memcpy((*d)->str, s, length + 1);
104 *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size);
107 static struct kdbus_bloom_filter *append_bloom(struct kdbus_item **d, size_t length) {
108 struct kdbus_item *i;
114 i->size = offsetof(struct kdbus_item, bloom_filter) +
115 offsetof(struct kdbus_bloom_filter, data) +
117 i->type = KDBUS_ITEM_BLOOM_FILTER;
119 *d = (struct kdbus_item *) ((uint8_t*) i + i->size);
121 return &i->bloom_filter;
124 static void append_fds(struct kdbus_item **d, const int fds[], unsigned n_fds) {
130 (*d)->size = offsetof(struct kdbus_item, fds) + sizeof(int) * n_fds;
131 (*d)->type = KDBUS_ITEM_FDS;
132 memcpy((*d)->fds, fds, sizeof(int) * n_fds);
134 *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size);
137 static int bus_message_setup_bloom(sd_bus_message *m, struct kdbus_bloom_filter *bloom) {
146 memzero(data, m->bus->bloom_size);
147 bloom->generation = 0;
149 bloom_add_pair(data, m->bus->bloom_size, m->bus->bloom_n_hash, "message-type", bus_message_type_to_string(m->header->type));
152 bloom_add_pair(data, m->bus->bloom_size, m->bus->bloom_n_hash, "interface", m->interface);
154 bloom_add_pair(data, m->bus->bloom_size, m->bus->bloom_n_hash, "member", m->member);
156 bloom_add_pair(data, m->bus->bloom_size, m->bus->bloom_n_hash, "path", m->path);
157 bloom_add_pair(data, m->bus->bloom_size, m->bus->bloom_n_hash, "path-slash-prefix", m->path);
158 bloom_add_prefixes(data, m->bus->bloom_size, m->bus->bloom_n_hash, "path-slash-prefix", m->path, '/');
161 r = sd_bus_message_rewind(m, true);
165 for (i = 0; i < 64; i++) {
168 char buf[sizeof("arg")-1 + 2 + sizeof("-slash-prefix")];
171 r = sd_bus_message_peek_type(m, &type, NULL);
175 if (type != SD_BUS_TYPE_STRING &&
176 type != SD_BUS_TYPE_OBJECT_PATH &&
177 type != SD_BUS_TYPE_SIGNATURE)
180 r = sd_bus_message_read_basic(m, type, &t);
184 e = stpcpy(buf, "arg");
186 *(e++) = '0' + (char) i;
188 *(e++) = '0' + (char) (i / 10);
189 *(e++) = '0' + (char) (i % 10);
193 bloom_add_pair(data, m->bus->bloom_size, m->bus->bloom_n_hash, buf, t);
195 strcpy(e, "-dot-prefix");
196 bloom_add_prefixes(data, m->bus->bloom_size, m->bus->bloom_n_hash, buf, t, '.');
197 strcpy(e, "-slash-prefix");
198 bloom_add_prefixes(data, m->bus->bloom_size, m->bus->bloom_n_hash, buf, t, '/');
204 static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) {
205 struct bus_body_part *part;
206 struct kdbus_item *d;
207 const char *destination;
218 /* We put this together only once, if this message is reused
219 * we reuse the earlier-built version */
223 destination = m->destination ?: m->destination_ptr;
226 r = bus_kernel_parse_unique_name(destination, &unique);
234 sz = offsetof(struct kdbus_msg, items);
236 assert_cc(ALIGN8(offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec)) ==
237 ALIGN8(offsetof(struct kdbus_item, memfd) + sizeof(struct kdbus_memfd)));
239 /* Add in fixed header, fields header and payload */
240 sz += (1 + m->n_body_parts) *
241 ALIGN8(offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec));
243 /* Add space for bloom filter */
244 sz += ALIGN8(offsetof(struct kdbus_item, bloom_filter) +
245 offsetof(struct kdbus_bloom_filter, data) +
248 /* Add in well-known destination header */
250 dl = strlen(destination);
251 sz += ALIGN8(offsetof(struct kdbus_item, str) + dl + 1);
254 /* Add space for unix fds */
256 sz += ALIGN8(offsetof(struct kdbus_item, fds) + sizeof(int)*m->n_fds);
258 m->kdbus = memalign(8, sz);
264 m->free_kdbus = true;
265 memzero(m->kdbus, sz);
268 ((m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED) ? 0 : KDBUS_MSG_FLAGS_EXPECT_REPLY) |
269 ((m->header->flags & BUS_MESSAGE_NO_AUTO_START) ? KDBUS_MSG_FLAGS_NO_AUTO_START : 0);
272 /* verify_destination_id will usually be 0, which makes the kernel driver only look
273 * at the provided well-known name. Otherwise, the kernel will make sure the provided
274 * destination id matches the owner of the provided weel-known-name, and fail if they
275 * differ. Currently, this is only needed for bus-proxyd. */
276 m->kdbus->dst_id = m->verify_destination_id;
278 m->kdbus->dst_id = destination ? unique : KDBUS_DST_ID_BROADCAST;
281 m->kdbus->payload_type = KDBUS_PAYLOAD_DBUS;
282 m->kdbus->cookie = (uint64_t) m->header->serial;
283 m->kdbus->priority = m->priority;
285 if (m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED) {
286 m->kdbus->cookie_reply = m->reply_cookie;
290 assert_se(clock_gettime(CLOCK_MONOTONIC_COARSE, &now) == 0);
291 m->kdbus->timeout_ns = now.tv_sec * NSEC_PER_SEC + now.tv_nsec +
292 m->timeout * NSEC_PER_USEC;
298 append_destination(&d, destination, dl);
300 append_payload_vec(&d, m->header, BUS_MESSAGE_BODY_BEGIN(m));
302 MESSAGE_FOREACH_PART(part, i, m) {
304 /* If this is padding then simply send a
305 * vector with a NULL data pointer which the
306 * kernel will just pass through. This is the
307 * most efficient way to encode zeroes */
309 append_payload_vec(&d, NULL, part->size);
313 if (part->memfd >= 0 && part->sealed && destination) {
314 /* Try to send a memfd, if the part is
315 * sealed and this is not a broadcast. Since we can only */
317 append_payload_memfd(&d, part->memfd, part->size);
321 /* Otherwise, let's send a vector to the actual data.
322 * For that, we need to map it first. */
323 r = bus_body_part_map(part);
327 append_payload_vec(&d, part->data, part->size);
330 if (m->kdbus->dst_id == KDBUS_DST_ID_BROADCAST) {
331 struct kdbus_bloom_filter *bloom;
333 bloom = append_bloom(&d, m->bus->bloom_size);
334 r = bus_message_setup_bloom(m, bloom);
340 append_fds(&d, m->fds, m->n_fds);
342 m->kdbus->size = (uint8_t*) d - (uint8_t*) m->kdbus;
343 assert(m->kdbus->size <= sz);
352 static void unset_memfds(struct sd_bus_message *m) {
353 struct bus_body_part *part;
358 /* Make sure the memfds are not freed twice */
359 MESSAGE_FOREACH_PART(part, i, m)
360 if (part->memfd >= 0)
364 static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) {
365 sd_bus_message *m = NULL;
366 struct kdbus_item *d;
368 _cleanup_free_ int *fds = NULL;
369 struct bus_header *h = NULL;
370 size_t total, n_bytes = 0, idx = 0;
371 const char *destination = NULL, *seclabel = NULL;
376 assert(k->payload_type == KDBUS_PAYLOAD_DBUS);
378 KDBUS_ITEM_FOREACH(d, k, items) {
381 l = d->size - offsetof(struct kdbus_item, data);
385 case KDBUS_ITEM_PAYLOAD_OFF:
387 h = (struct bus_header *)((uint8_t *)k + d->vec.offset);
389 if (!bus_header_is_complete(h, d->vec.size))
393 n_bytes += d->vec.size;
396 case KDBUS_ITEM_PAYLOAD_MEMFD:
400 n_bytes += d->memfd.size;
403 case KDBUS_ITEM_FDS: {
408 f = realloc(fds, sizeof(int) * (n_fds + j));
413 memcpy(fds + n_fds, d->fds, sizeof(int) * j);
418 case KDBUS_ITEM_SECLABEL:
427 r = bus_header_message_size(h, &total);
431 if (n_bytes != total)
434 /* on kdbus we only speak native endian gvariant, never dbus1
435 * marshalling or reverse endian */
436 if (h->version != 2 ||
437 h->endian != BUS_NATIVE_ENDIAN)
440 r = bus_message_from_header(bus, h, sizeof(struct bus_header), fds, n_fds, NULL, seclabel, 0, &m);
444 /* The well-known names list is different from the other
445 credentials. If we asked for it, but nothing is there, this
446 means that the list of well-known names is simply empty, not
447 that we lack any data */
449 m->creds.mask |= (SD_BUS_CREDS_UNIQUE_NAME|SD_BUS_CREDS_WELL_KNOWN_NAMES) & bus->creds_mask;
451 KDBUS_ITEM_FOREACH(d, k, items) {
454 l = d->size - offsetof(struct kdbus_item, data);
458 case KDBUS_ITEM_PAYLOAD_OFF: {
461 begin_body = BUS_MESSAGE_BODY_BEGIN(m);
463 if (idx + d->vec.size > begin_body) {
464 struct bus_body_part *part;
466 /* Contains body material */
468 part = message_append_part(m);
474 /* A -1 offset is NUL padding. */
475 part->is_zero = d->vec.offset == ~0ULL;
477 if (idx >= begin_body) {
479 part->data = (uint8_t *)k + d->vec.offset;
480 part->size = d->vec.size;
483 part->data = (uint8_t *)k + d->vec.offset + (begin_body - idx);
484 part->size = d->vec.size - (begin_body - idx);
494 case KDBUS_ITEM_PAYLOAD_MEMFD: {
495 struct bus_body_part *part;
497 if (idx < BUS_MESSAGE_BODY_BEGIN(m)) {
502 part = message_append_part(m);
508 part->memfd = d->memfd.fd;
509 part->size = d->memfd.size;
512 idx += d->memfd.size;
516 case KDBUS_ITEM_PIDS:
518 /* The PID starttime/TID might be missing,
519 * when the data is faked by some data bus
520 * proxy and it lacks that information about
521 * the real client since SO_PEERCRED is used
524 if (d->pids.pid > 0) {
525 m->creds.pid = (pid_t) d->pids.pid;
526 m->creds.mask |= SD_BUS_CREDS_PID & bus->creds_mask;
529 if (d->pids.starttime > 0) {
530 m->creds.pid_starttime = d->pids.starttime / NSEC_PER_USEC;
531 m->creds.mask |= SD_BUS_CREDS_PID_STARTTIME & bus->creds_mask;
534 if (d->pids.tid > 0) {
535 m->creds.tid = (pid_t) d->pids.tid;
536 m->creds.mask |= SD_BUS_CREDS_TID & bus->creds_mask;
541 case KDBUS_ITEM_CREDS:
543 /* EUID/SUID/FSUID/EGID/SGID/FSGID might be missing too (see above). */
545 if ((uid_t) d->creds.uid != (uid_t) -1) {
546 m->creds.uid = (uid_t) d->creds.uid;
547 m->creds.mask |= SD_BUS_CREDS_UID & bus->creds_mask;
550 if ((uid_t) d->creds.euid != (uid_t) -1) {
551 m->creds.euid = (uid_t) d->creds.euid;
552 m->creds.mask |= SD_BUS_CREDS_EUID & bus->creds_mask;
555 if ((uid_t) d->creds.suid != (uid_t) -1) {
556 m->creds.suid = (uid_t) d->creds.suid;
557 m->creds.mask |= SD_BUS_CREDS_SUID & bus->creds_mask;
560 if ((uid_t) d->creds.fsuid != (uid_t) -1) {
561 m->creds.fsuid = (uid_t) d->creds.fsuid;
562 m->creds.mask |= SD_BUS_CREDS_FSUID & bus->creds_mask;
565 if ((gid_t) d->creds.gid != (gid_t) -1) {
566 m->creds.gid = (gid_t) d->creds.gid;
567 m->creds.mask |= SD_BUS_CREDS_GID & bus->creds_mask;
570 if ((gid_t) d->creds.egid != (gid_t) -1) {
571 m->creds.egid = (gid_t) d->creds.egid;
572 m->creds.mask |= SD_BUS_CREDS_EGID & bus->creds_mask;
575 if ((gid_t) d->creds.sgid != (gid_t) -1) {
576 m->creds.sgid = (gid_t) d->creds.sgid;
577 m->creds.mask |= SD_BUS_CREDS_SGID & bus->creds_mask;
580 if ((gid_t) d->creds.fsgid != (gid_t) -1) {
581 m->creds.fsgid = (gid_t) d->creds.fsgid;
582 m->creds.mask |= SD_BUS_CREDS_FSGID & bus->creds_mask;
587 case KDBUS_ITEM_TIMESTAMP:
589 if (bus->attach_flags & KDBUS_ATTACH_TIMESTAMP) {
590 m->realtime = d->timestamp.realtime_ns / NSEC_PER_USEC;
591 m->monotonic = d->timestamp.monotonic_ns / NSEC_PER_USEC;
592 m->seqnum = d->timestamp.seqnum;
597 case KDBUS_ITEM_PID_COMM:
598 m->creds.comm = d->str;
599 m->creds.mask |= SD_BUS_CREDS_COMM & bus->creds_mask;
602 case KDBUS_ITEM_TID_COMM:
603 m->creds.tid_comm = d->str;
604 m->creds.mask |= SD_BUS_CREDS_TID_COMM & bus->creds_mask;
608 m->creds.exe = d->str;
609 m->creds.mask |= SD_BUS_CREDS_EXE & bus->creds_mask;
612 case KDBUS_ITEM_CMDLINE:
613 m->creds.cmdline = d->str;
614 m->creds.cmdline_size = l;
615 m->creds.mask |= SD_BUS_CREDS_CMDLINE & bus->creds_mask;
618 case KDBUS_ITEM_CGROUP:
619 m->creds.cgroup = d->str;
620 m->creds.mask |= (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_OWNER_UID) & bus->creds_mask;
622 r = bus_get_root_path(bus);
626 m->creds.cgroup_root = bus->cgroup_root;
630 case KDBUS_ITEM_AUDIT:
631 m->creds.audit_session_id = (uint32_t) d->audit.sessionid;
632 m->creds.audit_login_uid = (uid_t) d->audit.loginuid;
633 m->creds.mask |= (SD_BUS_CREDS_AUDIT_SESSION_ID|SD_BUS_CREDS_AUDIT_LOGIN_UID) & bus->creds_mask;
636 case KDBUS_ITEM_CAPS:
637 m->creds.capability = (uint8_t *) d->caps.caps;
638 m->creds.capability_size = d->size - offsetof(struct kdbus_item, caps.caps);
639 m->creds.mask |= (SD_BUS_CREDS_EFFECTIVE_CAPS|SD_BUS_CREDS_PERMITTED_CAPS|SD_BUS_CREDS_INHERITABLE_CAPS|SD_BUS_CREDS_BOUNDING_CAPS) & bus->creds_mask;
642 case KDBUS_ITEM_DST_NAME:
643 if (!service_name_is_valid(d->str))
646 destination = d->str;
649 case KDBUS_ITEM_OWNED_NAME:
650 if (!service_name_is_valid(d->name.name))
653 r = strv_extend(&m->creds.well_known_names, d->name.name);
658 case KDBUS_ITEM_CONN_DESCRIPTION:
659 m->creds.description = d->str;
660 m->creds.mask |= SD_BUS_CREDS_DESCRIPTION & bus->creds_mask;
663 case KDBUS_ITEM_AUXGROUPS:
665 if (bus->creds_mask & SD_BUS_CREDS_SUPPLEMENTARY_GIDS) {
668 n = (d->size - offsetof(struct kdbus_item, data64)) / sizeof(uint64_t);
675 for (i = 0; i < n; i++)
676 u[i] = (uid_t) d->data64[i];
678 m->creds.supplementary_gids = u;
679 m->creds.n_supplementary_gids = n;
681 m->creds.mask |= SD_BUS_CREDS_SUPPLEMENTARY_GIDS;
687 case KDBUS_ITEM_SECLABEL:
691 log_debug("Got unknown field from kernel %llu", d->type);
695 r = bus_message_parse_fields(m);
699 /* Override information from the user header with data from the kernel */
700 if (k->src_id == KDBUS_SRC_ID_KERNEL)
701 m->sender = m->creds.unique_name = (char*) "org.freedesktop.DBus";
703 snprintf(m->sender_buffer, sizeof(m->sender_buffer), ":1.%llu", (unsigned long long) k->src_id);
704 m->sender = m->creds.unique_name = m->sender_buffer;
708 m->destination = destination;
709 else if (k->dst_id == KDBUS_DST_ID_BROADCAST)
710 m->destination = NULL;
711 else if (k->dst_id == KDBUS_DST_ID_NAME)
712 m->destination = bus->unique_name; /* fill in unique name if the well-known name is missing */
714 snprintf(m->destination_buffer, sizeof(m->destination_buffer), ":1.%llu", (unsigned long long) k->dst_id);
715 m->destination = m->destination_buffer;
718 /* We take possession of the kmsg struct now */
720 m->release_kdbus = true;
724 bus->rqueue[bus->rqueue_size++] = m;
730 sd_bus_message_unref(m);
735 int bus_kernel_take_fd(sd_bus *b) {
736 struct kdbus_cmd_hello *hello;
737 struct kdbus_item *item;
738 _cleanup_free_ char *g = NULL;
740 size_t l = 0, m = 0, sz;
750 if (b->description) {
751 g = bus_label_escape(b->description);
759 /* If no name is explicitly set, we'll include a hint
760 * indicating the library implementation, a hint which
761 * kind of bus this is and the thread name */
763 assert_se(prctl(PR_GET_NAME, (unsigned long) pr) >= 0);
766 name = b->is_system ? "sd-system" :
767 b->is_user ? "sd-user" : "sd";
769 _cleanup_free_ char *e = NULL;
771 e = bus_label_escape(pr);
775 g = strappend(b->is_system ? "sd-system-" :
776 b->is_user ? "sd-user-" : "sd-",
784 b->description = bus_label_unescape(name);
791 sz = ALIGN8(offsetof(struct kdbus_cmd_hello, items)) +
792 ALIGN8(offsetof(struct kdbus_item, str) + m + 1);
794 if (b->fake_creds_valid)
795 sz += ALIGN8(offsetof(struct kdbus_item, creds) + sizeof(struct kdbus_creds));
797 if (b->fake_pids_valid)
798 sz += ALIGN8(offsetof(struct kdbus_item, pids) + sizeof(struct kdbus_pids));
801 l = strlen(b->fake_label);
802 sz += ALIGN8(offsetof(struct kdbus_item, str) + l + 1);
805 hello = alloca0_align(sz, 8);
807 hello->flags = b->hello_flags;
808 hello->attach_flags_send = _KDBUS_ATTACH_ANY;
809 hello->attach_flags_recv = b->attach_flags;
810 hello->pool_size = KDBUS_POOL_SIZE;
814 item->size = offsetof(struct kdbus_item, str) + m + 1;
815 item->type = KDBUS_ITEM_CONN_DESCRIPTION;
816 memcpy(item->str, name, m + 1);
817 item = KDBUS_ITEM_NEXT(item);
819 if (b->fake_creds_valid) {
820 item->size = offsetof(struct kdbus_item, creds) + sizeof(struct kdbus_creds);
821 item->type = KDBUS_ITEM_CREDS;
822 item->creds = b->fake_creds;
824 item = KDBUS_ITEM_NEXT(item);
827 if (b->fake_pids_valid) {
828 item->size = offsetof(struct kdbus_item, pids) + sizeof(struct kdbus_pids);
829 item->type = KDBUS_ITEM_PIDS;
830 item->pids = b->fake_pids;
832 item = KDBUS_ITEM_NEXT(item);
836 item->size = offsetof(struct kdbus_item, str) + l + 1;
837 item->type = KDBUS_ITEM_SECLABEL;
838 memcpy(item->str, b->fake_label, l+1);
841 r = ioctl(b->input_fd, KDBUS_CMD_HELLO, hello);
845 if (!b->kdbus_buffer) {
846 b->kdbus_buffer = mmap(NULL, KDBUS_POOL_SIZE, PROT_READ, MAP_SHARED, b->input_fd, 0);
847 if (b->kdbus_buffer == MAP_FAILED) {
848 b->kdbus_buffer = NULL;
853 /* The higher 32bit of the bus_flags fields are considered
854 * 'incompatible flags'. Refuse them all for now. */
855 if (hello->bus_flags > 0xFFFFFFFFULL)
858 if (!bloom_validate_parameters((size_t) hello->bloom.size, (unsigned) hello->bloom.n_hash))
861 b->bloom_size = (size_t) hello->bloom.size;
862 b->bloom_n_hash = (unsigned) hello->bloom.n_hash;
864 if (asprintf(&b->unique_name, ":1.%llu", (unsigned long long) hello->id) < 0)
867 b->unique_id = hello->id;
870 b->bus_client = true;
871 b->can_fds = !!(hello->flags & KDBUS_HELLO_ACCEPT_FD);
872 b->message_version = 2;
873 b->message_endian = BUS_NATIVE_ENDIAN;
875 /* the kernel told us the UUID of the underlying bus */
876 memcpy(b->server_id.bytes, hello->id128, sizeof(b->server_id.bytes));
878 return bus_start_running(b);
881 int bus_kernel_connect(sd_bus *b) {
883 assert(b->input_fd < 0);
884 assert(b->output_fd < 0);
890 b->input_fd = open(b->kernel, O_RDWR|O_NOCTTY|O_CLOEXEC);
894 b->output_fd = b->input_fd;
896 return bus_kernel_take_fd(b);
899 static void close_kdbus_msg(sd_bus *bus, struct kdbus_msg *k) {
900 struct kdbus_cmd_free cmd;
901 struct kdbus_item *d;
907 cmd.offset = (uint8_t *)k - (uint8_t *)bus->kdbus_buffer;
909 KDBUS_ITEM_FOREACH(d, k, items) {
911 if (d->type == KDBUS_ITEM_FDS)
912 close_many(d->fds, (d->size - offsetof(struct kdbus_item, fds)) / sizeof(int));
913 else if (d->type == KDBUS_ITEM_PAYLOAD_MEMFD)
914 safe_close(d->memfd.fd);
917 (void) ioctl(bus->input_fd, KDBUS_CMD_FREE, &cmd);
920 int bus_kernel_write_message(sd_bus *bus, sd_bus_message *m, bool hint_sync_call) {
925 assert(bus->state == BUS_RUNNING);
927 /* If we can't deliver, we want room for the error message */
928 r = bus_rqueue_make_room(bus);
932 r = bus_message_setup_kmsg(bus, m);
936 /* If this is a synchronous method call, then let's tell the
937 * kernel, so that it can pass CPU time/scheduling to the
938 * destination for the time, if it wants to. If we
939 * synchronously wait for the result anyway, we won't need CPU
942 m->kdbus->flags |= KDBUS_MSG_FLAGS_EXPECT_REPLY|KDBUS_MSG_FLAGS_SYNC_REPLY;
944 r = ioctl(bus->output_fd, KDBUS_CMD_MSG_SEND, m->kdbus);
946 _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
947 sd_bus_message *reply;
949 if (errno == EAGAIN || errno == EINTR)
951 else if (errno == ENXIO || errno == ESRCH) {
953 /* ENXIO: unique name not known
954 * ESRCH: well-known name not known */
956 if (m->header->type == SD_BUS_MESSAGE_METHOD_CALL)
957 sd_bus_error_setf(&error, SD_BUS_ERROR_SERVICE_UNKNOWN, "Destination %s not known", m->destination);
959 log_debug("Could not deliver message to %s as destination is not known. Ignoring.", m->destination);
963 } else if (errno == EADDRNOTAVAIL) {
965 /* EADDRNOTAVAIL: activation is possible, but turned off in request flags */
967 if (m->header->type == SD_BUS_MESSAGE_METHOD_CALL)
968 sd_bus_error_setf(&error, SD_BUS_ERROR_SERVICE_UNKNOWN, "Activation of %s not requested", m->destination);
970 log_debug("Could not deliver message to %s as destination is not activated. Ignoring.", m->destination);
976 r = bus_message_new_synthetic_error(
978 BUS_MESSAGE_COOKIE(m),
985 r = bus_seal_synthetic_message(bus, reply);
989 bus->rqueue[bus->rqueue_size++] = reply;
991 } else if (hint_sync_call) {
994 k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + m->kdbus->offset_reply);
997 if (k->payload_type == KDBUS_PAYLOAD_DBUS) {
999 r = bus_kernel_make_message(bus, k);
1001 close_kdbus_msg(bus, k);
1003 /* Anybody can send us invalid messages, let's just drop them. */
1004 if (r == -EBADMSG || r == -EPROTOTYPE)
1005 log_debug("Ignoring invalid message: %s", strerror(-r));
1010 log_debug("Ignoring message with unknown payload type %llu.", (unsigned long long) k->payload_type);
1011 close_kdbus_msg(bus, k);
1018 static int push_name_owner_changed(sd_bus *bus, const char *name, const char *old_owner, const char *new_owner) {
1019 _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
1024 r = sd_bus_message_new_signal(
1027 "/org/freedesktop/DBus",
1028 "org.freedesktop.DBus",
1029 "NameOwnerChanged");
1033 r = sd_bus_message_append(m, "sss", name, old_owner, new_owner);
1037 m->sender = "org.freedesktop.DBus";
1039 r = bus_seal_synthetic_message(bus, m);
1043 bus->rqueue[bus->rqueue_size++] = m;
1049 static int translate_name_change(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item *d) {
1050 char new_owner[UNIQUE_NAME_MAX], old_owner[UNIQUE_NAME_MAX];
1056 if (d->type == KDBUS_ITEM_NAME_ADD || (d->name_change.old_id.flags & (KDBUS_NAME_IN_QUEUE|KDBUS_NAME_ACTIVATOR)))
1059 sprintf(old_owner, ":1.%llu", (unsigned long long) d->name_change.old_id.id);
1061 if (d->type == KDBUS_ITEM_NAME_REMOVE || (d->name_change.new_id.flags & (KDBUS_NAME_IN_QUEUE|KDBUS_NAME_ACTIVATOR))) {
1063 if (isempty(old_owner))
1068 sprintf(new_owner, ":1.%llu", (unsigned long long) d->name_change.new_id.id);
1070 return push_name_owner_changed(bus, d->name_change.name, old_owner, new_owner);
1073 static int translate_id_change(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item *d) {
1074 char owner[UNIQUE_NAME_MAX];
1080 sprintf(owner, ":1.%llu", d->id_change.id);
1082 return push_name_owner_changed(
1084 d->type == KDBUS_ITEM_ID_ADD ? NULL : owner,
1085 d->type == KDBUS_ITEM_ID_ADD ? owner : NULL);
1088 static int translate_reply(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item *d) {
1089 _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
1096 r = bus_message_new_synthetic_error(
1099 d->type == KDBUS_ITEM_REPLY_TIMEOUT ?
1100 &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_NO_REPLY, "Method call timed out") :
1101 &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_NO_REPLY, "Method call peer died"),
1106 m->sender = "org.freedesktop.DBus";
1108 r = bus_seal_synthetic_message(bus, m);
1112 bus->rqueue[bus->rqueue_size++] = m;
1118 static int bus_kernel_translate_message(sd_bus *bus, struct kdbus_msg *k) {
1119 struct kdbus_item *d, *found = NULL;
1121 static int (* const translate[])(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item *d) = {
1122 [KDBUS_ITEM_NAME_ADD - _KDBUS_ITEM_KERNEL_BASE] = translate_name_change,
1123 [KDBUS_ITEM_NAME_REMOVE - _KDBUS_ITEM_KERNEL_BASE] = translate_name_change,
1124 [KDBUS_ITEM_NAME_CHANGE - _KDBUS_ITEM_KERNEL_BASE] = translate_name_change,
1126 [KDBUS_ITEM_ID_ADD - _KDBUS_ITEM_KERNEL_BASE] = translate_id_change,
1127 [KDBUS_ITEM_ID_REMOVE - _KDBUS_ITEM_KERNEL_BASE] = translate_id_change,
1129 [KDBUS_ITEM_REPLY_TIMEOUT - _KDBUS_ITEM_KERNEL_BASE] = translate_reply,
1130 [KDBUS_ITEM_REPLY_DEAD - _KDBUS_ITEM_KERNEL_BASE] = translate_reply,
1135 assert(k->payload_type == KDBUS_PAYLOAD_KERNEL);
1137 KDBUS_ITEM_FOREACH(d, k, items) {
1138 if (d->type >= _KDBUS_ITEM_KERNEL_BASE && d->type < _KDBUS_ITEM_KERNEL_BASE + ELEMENTSOF(translate)) {
1143 log_debug("Got unknown field from kernel %llu", d->type);
1147 log_debug("Didn't find a kernel message to translate.");
1151 return translate[found->type - _KDBUS_ITEM_KERNEL_BASE](bus, k, found);
1154 int bus_kernel_read_message(sd_bus *bus, bool hint_priority, int64_t priority) {
1155 struct kdbus_cmd_recv recv = {};
1156 struct kdbus_msg *k;
1161 r = bus_rqueue_make_room(bus);
1165 if (hint_priority) {
1166 recv.flags |= KDBUS_RECV_USE_PRIORITY;
1167 recv.priority = priority;
1170 r = ioctl(bus->input_fd, KDBUS_CMD_MSG_RECV, &recv);
1172 if (errno == EAGAIN)
1178 k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + recv.offset);
1179 if (k->payload_type == KDBUS_PAYLOAD_DBUS) {
1180 r = bus_kernel_make_message(bus, k);
1182 /* Anybody can send us invalid messages, let's just drop them. */
1183 if (r == -EBADMSG || r == -EPROTOTYPE) {
1184 log_debug("Ignoring invalid message: %s", strerror(-r));
1188 } else if (k->payload_type == KDBUS_PAYLOAD_KERNEL)
1189 r = bus_kernel_translate_message(bus, k);
1191 log_debug("Ignoring message with unknown payload type %llu.", (unsigned long long) k->payload_type);
1196 close_kdbus_msg(bus, k);
1198 return r < 0 ? r : 1;
1201 int bus_kernel_pop_memfd(sd_bus *bus, void **address, size_t *mapped, size_t *allocated) {
1202 struct memfd_cache *c;
1209 if (!bus || !bus->is_kernel)
1212 assert_se(pthread_mutex_lock(&bus->memfd_cache_mutex) >= 0);
1214 if (bus->n_memfd_cache <= 0) {
1217 assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
1219 r = memfd_new(bus->description);
1229 c = &bus->memfd_cache[--bus->n_memfd_cache];
1232 assert(c->mapped == 0 || c->address);
1234 *address = c->address;
1235 *mapped = c->mapped;
1236 *allocated = c->allocated;
1239 assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
1244 static void close_and_munmap(int fd, void *address, size_t size) {
1246 assert_se(munmap(address, PAGE_ALIGN(size)) >= 0);
1251 void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t mapped, size_t allocated) {
1252 struct memfd_cache *c;
1253 uint64_t max_mapped = PAGE_ALIGN(MEMFD_CACHE_ITEM_SIZE_MAX);
1256 assert(mapped == 0 || address);
1258 if (!bus || !bus->is_kernel) {
1259 close_and_munmap(fd, address, mapped);
1263 assert_se(pthread_mutex_lock(&bus->memfd_cache_mutex) >= 0);
1265 if (bus->n_memfd_cache >= ELEMENTSOF(bus->memfd_cache)) {
1266 assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
1268 close_and_munmap(fd, address, mapped);
1272 c = &bus->memfd_cache[bus->n_memfd_cache++];
1274 c->address = address;
1276 /* If overly long, let's return a bit to the OS */
1277 if (mapped > max_mapped) {
1278 assert_se(memfd_set_size(fd, max_mapped) >= 0);
1279 assert_se(munmap((uint8_t*) address + max_mapped, PAGE_ALIGN(mapped - max_mapped)) >= 0);
1280 c->mapped = c->allocated = max_mapped;
1283 c->allocated = allocated;
1286 assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
1289 void bus_kernel_flush_memfd(sd_bus *b) {
1294 for (i = 0; i < b->n_memfd_cache; i++)
1295 close_and_munmap(b->memfd_cache[i].fd, b->memfd_cache[i].address, b->memfd_cache[i].mapped);
1298 int kdbus_translate_request_name_flags(uint64_t flags, uint64_t *kdbus_flags) {
1301 assert(kdbus_flags);
1303 if (flags & SD_BUS_NAME_ALLOW_REPLACEMENT)
1304 f |= KDBUS_NAME_ALLOW_REPLACEMENT;
1306 if (flags & SD_BUS_NAME_REPLACE_EXISTING)
1307 f |= KDBUS_NAME_REPLACE_EXISTING;
1309 if (flags & SD_BUS_NAME_QUEUE)
1310 f |= KDBUS_NAME_QUEUE;
1316 int kdbus_translate_attach_flags(uint64_t mask, uint64_t *kdbus_mask) {
1321 if (mask & (SD_BUS_CREDS_UID|SD_BUS_CREDS_EUID|SD_BUS_CREDS_SUID|SD_BUS_CREDS_FSUID|
1322 SD_BUS_CREDS_GID|SD_BUS_CREDS_EGID|SD_BUS_CREDS_SGID|SD_BUS_CREDS_FSGID))
1323 m |= KDBUS_ATTACH_CREDS;
1325 if (mask & (SD_BUS_CREDS_PID|SD_BUS_CREDS_PID_STARTTIME|SD_BUS_CREDS_TID))
1326 m |= KDBUS_ATTACH_PIDS;
1328 if (mask & SD_BUS_CREDS_COMM)
1329 m |= KDBUS_ATTACH_PID_COMM;
1331 if (mask & SD_BUS_CREDS_TID_COMM)
1332 m |= KDBUS_ATTACH_TID_COMM;
1334 if (mask & SD_BUS_CREDS_EXE)
1335 m |= KDBUS_ATTACH_EXE;
1337 if (mask & SD_BUS_CREDS_CMDLINE)
1338 m |= KDBUS_ATTACH_CMDLINE;
1340 if (mask & (SD_BUS_CREDS_CGROUP|SD_BUS_CREDS_UNIT|SD_BUS_CREDS_USER_UNIT|SD_BUS_CREDS_SLICE|SD_BUS_CREDS_SESSION|SD_BUS_CREDS_OWNER_UID))
1341 m |= KDBUS_ATTACH_CGROUP;
1343 if (mask & (SD_BUS_CREDS_EFFECTIVE_CAPS|SD_BUS_CREDS_PERMITTED_CAPS|SD_BUS_CREDS_INHERITABLE_CAPS|SD_BUS_CREDS_BOUNDING_CAPS))
1344 m |= KDBUS_ATTACH_CAPS;
1346 if (mask & SD_BUS_CREDS_SELINUX_CONTEXT)
1347 m |= KDBUS_ATTACH_SECLABEL;
1349 if (mask & (SD_BUS_CREDS_AUDIT_SESSION_ID|SD_BUS_CREDS_AUDIT_LOGIN_UID))
1350 m |= KDBUS_ATTACH_AUDIT;
1352 if (mask & SD_BUS_CREDS_WELL_KNOWN_NAMES)
1353 m |= KDBUS_ATTACH_NAMES;
1355 if (mask & SD_BUS_CREDS_DESCRIPTION)
1356 m |= KDBUS_ATTACH_CONN_DESCRIPTION;
1358 if (mask & SD_BUS_CREDS_SUPPLEMENTARY_GIDS)
1359 m |= KDBUS_ATTACH_AUXGROUPS;
1365 int bus_kernel_create_bus(const char *name, bool world, char **s) {
1366 struct kdbus_cmd_make *make;
1367 struct kdbus_item *n;
1373 fd = open("/sys/fs/kdbus/control", O_RDWR|O_NOCTTY|O_CLOEXEC);
1377 make = alloca0_align(ALIGN8(offsetof(struct kdbus_cmd_make, items) +
1378 offsetof(struct kdbus_item, data64) + sizeof(uint64_t) +
1379 offsetof(struct kdbus_item, str) +
1380 DECIMAL_STR_MAX(uid_t) + 1 + strlen(name) + 1),
1383 make->size = offsetof(struct kdbus_cmd_make, items);
1386 n->size = offsetof(struct kdbus_item, bloom_parameter) +
1387 sizeof(struct kdbus_bloom_parameter);
1388 n->type = KDBUS_ITEM_BLOOM_PARAMETER;
1390 n->bloom_parameter.size = DEFAULT_BLOOM_SIZE;
1391 n->bloom_parameter.n_hash = DEFAULT_BLOOM_N_HASH;
1393 assert_cc(DEFAULT_BLOOM_SIZE > 0);
1394 assert_cc(DEFAULT_BLOOM_N_HASH > 0);
1396 make->size += ALIGN8(n->size);
1398 n = KDBUS_ITEM_NEXT(n);
1399 sprintf(n->str, UID_FMT "-%s", getuid(), name);
1400 n->size = offsetof(struct kdbus_item, str) + strlen(n->str) + 1;
1401 n->type = KDBUS_ITEM_MAKE_NAME;
1402 make->size += ALIGN8(n->size);
1404 make->flags = world ? KDBUS_MAKE_ACCESS_WORLD : 0;
1406 if (ioctl(fd, KDBUS_CMD_BUS_MAKE, make) < 0) {
1414 p = strjoin("/sys/fs/kdbus/", n->str, "/bus", NULL);
1426 static int bus_kernel_translate_access(BusPolicyAccess access) {
1427 assert(access >= 0);
1428 assert(access < _BUS_POLICY_ACCESS_MAX);
1432 case BUS_POLICY_ACCESS_SEE:
1433 return KDBUS_POLICY_SEE;
1435 case BUS_POLICY_ACCESS_TALK:
1436 return KDBUS_POLICY_TALK;
1438 case BUS_POLICY_ACCESS_OWN:
1439 return KDBUS_POLICY_OWN;
1442 assert_not_reached("Unknown policy access");
1446 static int bus_kernel_translate_policy(const BusNamePolicy *policy, struct kdbus_item *item) {
1452 switch (policy->type) {
1454 case BUSNAME_POLICY_TYPE_USER: {
1455 const char *user = policy->name;
1458 r = get_user_creds(&user, &uid, NULL, NULL, NULL);
1462 item->policy_access.type = KDBUS_POLICY_ACCESS_USER;
1463 item->policy_access.id = uid;
1467 case BUSNAME_POLICY_TYPE_GROUP: {
1468 const char *group = policy->name;
1471 r = get_group_creds(&group, &gid);
1475 item->policy_access.type = KDBUS_POLICY_ACCESS_GROUP;
1476 item->policy_access.id = gid;
1481 assert_not_reached("Unknown policy type");
1484 item->policy_access.access = bus_kernel_translate_access(policy->access);
1489 int bus_kernel_open_bus_fd(const char *bus, char **path) {
1494 len = strlen("/sys/fs/kdbus/") + DECIMAL_STR_MAX(uid_t) + 1 + strlen(bus) + strlen("/bus") + 1;
1503 sprintf(p, "/sys/fs/kdbus/" UID_FMT "-%s/bus", getuid(), bus);
1505 fd = open(p, O_RDWR|O_NOCTTY|O_CLOEXEC);
1512 int bus_kernel_create_endpoint(const char *bus_name, const char *ep_name, char **ep_path) {
1513 _cleanup_free_ char *path = NULL;
1514 struct kdbus_cmd_make *make;
1515 struct kdbus_item *n;
1519 fd = bus_kernel_open_bus_fd(bus_name, &path);
1523 size = ALIGN8(offsetof(struct kdbus_cmd_make, items));
1524 size += ALIGN8(offsetof(struct kdbus_item, str) + strlen(ep_name) + 1);
1526 make = alloca0_align(size, 8);
1528 make->flags = KDBUS_MAKE_ACCESS_WORLD;
1532 n->type = KDBUS_ITEM_MAKE_NAME;
1533 n->size = offsetof(struct kdbus_item, str) + strlen(ep_name) + 1;
1534 strcpy(n->str, ep_name);
1536 if (ioctl(fd, KDBUS_CMD_ENDPOINT_MAKE, make) < 0) {
1544 p = strjoin(dirname(path), "/", ep_name, NULL);
1556 int bus_kernel_set_endpoint_policy(int fd, uid_t uid, BusEndpoint *ep) {
1558 struct kdbus_cmd_update *update;
1559 struct kdbus_item *n;
1560 BusEndpointPolicy *po;
1565 size = ALIGN8(offsetof(struct kdbus_cmd_update, items));
1567 HASHMAP_FOREACH(po, ep->policy_hash, i) {
1568 size += ALIGN8(offsetof(struct kdbus_item, str) + strlen(po->name) + 1);
1569 size += ALIGN8(offsetof(struct kdbus_item, policy_access) + sizeof(struct kdbus_policy_access));
1572 update = alloca0_align(size, 8);
1573 update->size = size;
1577 HASHMAP_FOREACH(po, ep->policy_hash, i) {
1578 n->type = KDBUS_ITEM_NAME;
1579 n->size = offsetof(struct kdbus_item, str) + strlen(po->name) + 1;
1580 strcpy(n->str, po->name);
1581 n = KDBUS_ITEM_NEXT(n);
1583 n->type = KDBUS_ITEM_POLICY_ACCESS;
1584 n->size = offsetof(struct kdbus_item, policy_access) + sizeof(struct kdbus_policy_access);
1586 n->policy_access.type = KDBUS_POLICY_ACCESS_USER;
1587 n->policy_access.access = bus_kernel_translate_access(po->access);
1588 n->policy_access.id = uid;
1590 n = KDBUS_ITEM_NEXT(n);
1593 r = ioctl(fd, KDBUS_CMD_ENDPOINT_UPDATE, update);
1600 int bus_kernel_make_starter(
1605 BusNamePolicy *policy,
1606 BusPolicyAccess world_policy) {
1608 struct kdbus_cmd_hello *hello;
1609 struct kdbus_item *n;
1610 size_t policy_cnt = 0;
1618 LIST_FOREACH(policy, po, policy)
1621 if (world_policy >= 0)
1624 size = ALIGN8(offsetof(struct kdbus_cmd_hello, items)) +
1625 ALIGN8(offsetof(struct kdbus_item, str) + strlen(name) + 1) +
1626 policy_cnt * ALIGN8(offsetof(struct kdbus_item, policy_access) + sizeof(struct kdbus_policy_access));
1628 hello = alloca0_align(size, 8);
1631 strcpy(n->str, name);
1632 n->size = offsetof(struct kdbus_item, str) + strlen(n->str) + 1;
1633 n->type = KDBUS_ITEM_NAME;
1634 n = KDBUS_ITEM_NEXT(n);
1636 LIST_FOREACH(policy, po, policy) {
1637 n->type = KDBUS_ITEM_POLICY_ACCESS;
1638 n->size = offsetof(struct kdbus_item, policy_access) + sizeof(struct kdbus_policy_access);
1640 r = bus_kernel_translate_policy(po, n);
1644 n = KDBUS_ITEM_NEXT(n);
1647 if (world_policy >= 0) {
1648 n->type = KDBUS_ITEM_POLICY_ACCESS;
1649 n->size = offsetof(struct kdbus_item, policy_access) + sizeof(struct kdbus_policy_access);
1650 n->policy_access.type = KDBUS_POLICY_ACCESS_WORLD;
1651 n->policy_access.access = bus_kernel_translate_access(world_policy);
1656 (activating ? KDBUS_HELLO_ACTIVATOR : KDBUS_HELLO_POLICY_HOLDER) |
1657 (accept_fd ? KDBUS_HELLO_ACCEPT_FD : 0);
1658 hello->pool_size = KDBUS_POOL_SIZE;
1659 hello->attach_flags_send = _KDBUS_ATTACH_ANY;
1660 hello->attach_flags_recv = _KDBUS_ATTACH_ALL;
1662 if (ioctl(fd, KDBUS_CMD_HELLO, hello) < 0)
1665 /* The higher 32bit of the bus_flags fields are considered
1666 * 'incompatible flags'. Refuse them all for now. */
1667 if (hello->bus_flags > 0xFFFFFFFFULL)
1670 if (!bloom_validate_parameters((size_t) hello->bloom.size, (unsigned) hello->bloom.n_hash))
1676 int bus_kernel_try_close(sd_bus *bus) {
1678 assert(bus->is_kernel);
1680 if (ioctl(bus->input_fd, KDBUS_CMD_BYEBYE) < 0)
1686 int bus_kernel_drop_one(int fd) {
1687 struct kdbus_cmd_recv recv = {
1688 .flags = KDBUS_RECV_DROP
1693 if (ioctl(fd, KDBUS_CMD_MSG_RECV, &recv) < 0)