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Diffstat (limited to 'src/libsystemd/sd-bus/bus-kernel.c')
-rw-r--r--src/libsystemd/sd-bus/bus-kernel.c1348
1 files changed, 1348 insertions, 0 deletions
diff --git a/src/libsystemd/sd-bus/bus-kernel.c b/src/libsystemd/sd-bus/bus-kernel.c
new file mode 100644
index 0000000000..f85b4d5676
--- /dev/null
+++ b/src/libsystemd/sd-bus/bus-kernel.c
@@ -0,0 +1,1348 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2013 Lennart Poettering
+
+ 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/>.
+***/
+
+#ifdef HAVE_VALGRIND_MEMCHECK_H
+#include <valgrind/memcheck.h>
+#endif
+
+#include <fcntl.h>
+#include <malloc.h>
+#include <sys/mman.h>
+
+#include "util.h"
+#include "strv.h"
+
+#include "bus-internal.h"
+#include "bus-message.h"
+#include "bus-kernel.h"
+#include "bus-bloom.h"
+#include "bus-util.h"
+#include "cgroup-util.h"
+
+#define UNIQUE_NAME_MAX (3+DECIMAL_STR_MAX(uint64_t))
+
+int bus_kernel_parse_unique_name(const char *s, uint64_t *id) {
+ int r;
+
+ assert(s);
+ assert(id);
+
+ if (!startswith(s, ":1."))
+ return 0;
+
+ r = safe_atou64(s + 3, id);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+static void append_payload_vec(struct kdbus_item **d, const void *p, size_t sz) {
+ assert(d);
+ assert(sz > 0);
+
+ *d = ALIGN8_PTR(*d);
+
+ /* Note that p can be NULL, which encodes a region full of
+ * zeroes, which is useful to optimize certain padding
+ * conditions */
+
+ (*d)->size = offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec);
+ (*d)->type = KDBUS_ITEM_PAYLOAD_VEC;
+ (*d)->vec.address = PTR_TO_UINT64(p);
+ (*d)->vec.size = sz;
+
+ *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size);
+}
+
+static void append_payload_memfd(struct kdbus_item **d, int memfd, size_t sz) {
+ assert(d);
+ assert(memfd >= 0);
+ assert(sz > 0);
+
+ *d = ALIGN8_PTR(*d);
+ (*d)->size = offsetof(struct kdbus_item, memfd) + sizeof(struct kdbus_memfd);
+ (*d)->type = KDBUS_ITEM_PAYLOAD_MEMFD;
+ (*d)->memfd.fd = memfd;
+ (*d)->memfd.size = sz;
+
+ *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size);
+}
+
+static void append_destination(struct kdbus_item **d, const char *s, size_t length) {
+ assert(d);
+ assert(s);
+
+ *d = ALIGN8_PTR(*d);
+
+ (*d)->size = offsetof(struct kdbus_item, str) + length + 1;
+ (*d)->type = KDBUS_ITEM_DST_NAME;
+ memcpy((*d)->str, s, length + 1);
+
+ *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size);
+}
+
+static void* append_bloom(struct kdbus_item **d, size_t length) {
+ void *r;
+
+ assert(d);
+
+ *d = ALIGN8_PTR(*d);
+
+ (*d)->size = offsetof(struct kdbus_item, data) + length;
+ (*d)->type = KDBUS_ITEM_BLOOM;
+ r = (*d)->data;
+
+ *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size);
+
+ return r;
+}
+
+static void append_fds(struct kdbus_item **d, const int fds[], unsigned n_fds) {
+ assert(d);
+ assert(fds);
+ assert(n_fds > 0);
+
+ *d = ALIGN8_PTR(*d);
+ (*d)->size = offsetof(struct kdbus_item, fds) + sizeof(int) * n_fds;
+ (*d)->type = KDBUS_ITEM_FDS;
+ memcpy((*d)->fds, fds, sizeof(int) * n_fds);
+
+ *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size);
+}
+
+static int bus_message_setup_bloom(sd_bus_message *m, void *bloom) {
+ unsigned i;
+ int r;
+
+ assert(m);
+ assert(bloom);
+
+ memset(bloom, 0, BLOOM_SIZE);
+
+ bloom_add_pair(bloom, "message-type", bus_message_type_to_string(m->header->type));
+
+ if (m->interface)
+ bloom_add_pair(bloom, "interface", m->interface);
+ if (m->member)
+ bloom_add_pair(bloom, "member", m->member);
+ if (m->path) {
+ bloom_add_pair(bloom, "path", m->path);
+ bloom_add_pair(bloom, "path-slash-prefix", m->path);
+ bloom_add_prefixes(bloom, "path-slash-prefix", m->path, '/');
+ }
+
+ r = sd_bus_message_rewind(m, true);
+ if (r < 0)
+ return r;
+
+ for (i = 0; i < 64; i++) {
+ char type;
+ const char *t;
+ char buf[sizeof("arg")-1 + 2 + sizeof("-slash-prefix")];
+ char *e;
+
+ r = sd_bus_message_peek_type(m, &type, NULL);
+ if (r < 0)
+ return r;
+
+ if (type != SD_BUS_TYPE_STRING &&
+ type != SD_BUS_TYPE_OBJECT_PATH &&
+ type != SD_BUS_TYPE_SIGNATURE)
+ break;
+
+ r = sd_bus_message_read_basic(m, type, &t);
+ if (r < 0)
+ return r;
+
+ e = stpcpy(buf, "arg");
+ if (i < 10)
+ *(e++) = '0' + (char) i;
+ else {
+ *(e++) = '0' + (char) (i / 10);
+ *(e++) = '0' + (char) (i % 10);
+ }
+
+ *e = 0;
+ bloom_add_pair(bloom, buf, t);
+
+ strcpy(e, "-dot-prefix");
+ bloom_add_prefixes(bloom, buf, t, '.');
+ strcpy(e, "-slash-prefix");
+ bloom_add_prefixes(bloom, buf, t, '/');
+ }
+
+ return 0;
+}
+
+static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) {
+ struct bus_body_part *part;
+ struct kdbus_item *d;
+ bool well_known;
+ uint64_t unique;
+ size_t sz, dl;
+ unsigned i;
+ int r;
+
+ assert(b);
+ assert(m);
+ assert(m->sealed);
+
+ if (m->kdbus)
+ return 0;
+
+ if (m->destination) {
+ r = bus_kernel_parse_unique_name(m->destination, &unique);
+ if (r < 0)
+ return r;
+
+ well_known = r == 0;
+ } else
+ well_known = false;
+
+ sz = offsetof(struct kdbus_msg, items);
+
+ assert_cc(ALIGN8(offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec)) ==
+ ALIGN8(offsetof(struct kdbus_item, memfd) + sizeof(struct kdbus_memfd)));
+
+ /* Add in fixed header, fields header and payload */
+ sz += (1 + m->n_body_parts) *
+ ALIGN8(offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec));
+
+ /* Add space for bloom filter */
+ sz += ALIGN8(offsetof(struct kdbus_item, data) + BLOOM_SIZE);
+
+ /* Add in well-known destination header */
+ if (well_known) {
+ dl = strlen(m->destination);
+ sz += ALIGN8(offsetof(struct kdbus_item, str) + dl + 1);
+ }
+
+ /* Add space for unix fds */
+ if (m->n_fds > 0)
+ sz += ALIGN8(offsetof(struct kdbus_item, fds) + sizeof(int)*m->n_fds);
+
+ m->kdbus = memalign(8, sz);
+ if (!m->kdbus) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ m->free_kdbus = true;
+ memset(m->kdbus, 0, sz);
+
+ m->kdbus->flags =
+ ((m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED) ? 0 : KDBUS_MSG_FLAGS_EXPECT_REPLY) |
+ ((m->header->flags & BUS_MESSAGE_NO_AUTO_START) ? KDBUS_MSG_FLAGS_NO_AUTO_START : 0);
+ m->kdbus->dst_id =
+ well_known ? 0 :
+ m->destination ? unique : KDBUS_DST_ID_BROADCAST;
+ m->kdbus->payload_type = KDBUS_PAYLOAD_DBUS;
+ m->kdbus->cookie = m->header->serial;
+
+ if (m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED)
+ m->kdbus->cookie_reply = m->reply_cookie;
+ else
+ m->kdbus->timeout_ns = m->timeout * NSEC_PER_USEC;
+
+ d = m->kdbus->items;
+
+ if (well_known)
+ append_destination(&d, m->destination, dl);
+
+ append_payload_vec(&d, m->header, BUS_MESSAGE_BODY_BEGIN(m));
+
+ MESSAGE_FOREACH_PART(part, i, m) {
+ if (part->is_zero) {
+ /* If this is padding then simply send a
+ * vector with a NULL data pointer which the
+ * kernel will just pass through. This is the
+ * most efficient way to encode zeroes */
+
+ append_payload_vec(&d, NULL, part->size);
+ continue;
+ }
+
+ if (part->memfd >= 0 && part->sealed && m->destination) {
+ /* Try to send a memfd, if the part is
+ * sealed and this is not a broadcast. Since we can only */
+
+ append_payload_memfd(&d, part->memfd, part->size);
+ continue;
+ }
+
+ /* Otherwise let's send a vector to the actual data,
+ * for that we need to map it first. */
+ r = bus_body_part_map(part);
+ if (r < 0)
+ goto fail;
+
+ append_payload_vec(&d, part->data, part->size);
+ }
+
+ if (m->kdbus->dst_id == KDBUS_DST_ID_BROADCAST) {
+ void *p;
+
+ p = append_bloom(&d, BLOOM_SIZE);
+ r = bus_message_setup_bloom(m, p);
+ if (r < 0)
+ goto fail;
+ }
+
+ if (m->n_fds > 0)
+ append_fds(&d, m->fds, m->n_fds);
+
+ m->kdbus->size = (uint8_t*) d - (uint8_t*) m->kdbus;
+ assert(m->kdbus->size <= sz);
+
+ return 0;
+
+fail:
+ m->poisoned = true;
+ return r;
+}
+
+static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) {
+ sd_bus_message *m = NULL;
+ struct kdbus_item *d;
+ unsigned n_fds = 0;
+ _cleanup_free_ int *fds = NULL;
+ struct bus_header *h = NULL;
+ size_t total, n_bytes = 0, idx = 0;
+ const char *destination = NULL, *seclabel = NULL;
+ int r;
+
+ assert(bus);
+ assert(k);
+ assert(k->payload_type == KDBUS_PAYLOAD_DBUS);
+
+ KDBUS_ITEM_FOREACH(d, k, items) {
+ size_t l;
+
+ l = d->size - offsetof(struct kdbus_item, data);
+
+ switch (d->type) {
+
+ case KDBUS_ITEM_PAYLOAD_OFF:
+ if (!h) {
+ h = (struct bus_header *)((uint8_t *)k + d->vec.offset);
+
+ if (!bus_header_is_complete(h, d->vec.size))
+ return -EBADMSG;
+ }
+
+ n_bytes += d->vec.size;
+ break;
+
+ case KDBUS_ITEM_PAYLOAD_MEMFD:
+ if (!h)
+ return -EBADMSG;
+
+ n_bytes += d->memfd.size;
+ break;
+
+ case KDBUS_ITEM_FDS: {
+ int *f;
+ unsigned j;
+
+ j = l / sizeof(int);
+ f = realloc(fds, sizeof(int) * (n_fds + j));
+ if (!f)
+ return -ENOMEM;
+
+ fds = f;
+ memcpy(fds + n_fds, d->fds, sizeof(int) * j);
+ n_fds += j;
+ break;
+ }
+
+ case KDBUS_ITEM_SECLABEL:
+ seclabel = d->str;
+ break;
+ }
+ }
+
+ if (!h)
+ return -EBADMSG;
+
+ r = bus_header_message_size(h, &total);
+ if (r < 0)
+ return r;
+
+ if (n_bytes != total)
+ return -EBADMSG;
+
+ /* on kdbus we only speak native endian gvariant, never dbus1
+ * marshalling or reverse endian */
+ if (h->version != 2 ||
+ h->endian != BUS_NATIVE_ENDIAN)
+ return -EPROTOTYPE;
+
+ r = bus_message_from_header(bus, h, sizeof(struct bus_header), fds, n_fds, NULL, seclabel, 0, &m);
+ if (r < 0)
+ return r;
+
+ /* The well-known names list is different from the other
+ credentials. If we asked for it, but nothing is there, this
+ means that the list of well-known names is simply empty, not
+ that we lack any data */
+
+ m->creds.mask |= (SD_BUS_CREDS_UNIQUE_NAME|SD_BUS_CREDS_WELL_KNOWN_NAMES) & bus->creds_mask;
+
+ KDBUS_ITEM_FOREACH(d, k, items) {
+ size_t l;
+
+ l = d->size - offsetof(struct kdbus_item, data);
+
+ switch (d->type) {
+
+ case KDBUS_ITEM_PAYLOAD_OFF: {
+ size_t begin_body;
+
+ begin_body = BUS_MESSAGE_BODY_BEGIN(m);
+
+ if (idx + d->vec.size > begin_body) {
+ struct bus_body_part *part;
+
+ /* Contains body material */
+
+ part = message_append_part(m);
+ if (!part) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ /* A -1 offset is NUL padding. */
+ part->is_zero = d->vec.offset == ~0ULL;
+
+ if (idx >= begin_body) {
+ if (!part->is_zero)
+ part->data = (uint8_t *)k + d->vec.offset;
+ part->size = d->vec.size;
+ } else {
+ if (!part->is_zero)
+ part->data = (uint8_t *)k + d->vec.offset + (begin_body - idx);
+ part->size = d->vec.size - (begin_body - idx);
+ }
+
+ part->sealed = true;
+ }
+
+ idx += d->vec.size;
+ break;
+ }
+
+ case KDBUS_ITEM_PAYLOAD_MEMFD: {
+ struct bus_body_part *part;
+
+ if (idx < BUS_MESSAGE_BODY_BEGIN(m)) {
+ r = -EBADMSG;
+ goto fail;
+ }
+
+ part = message_append_part(m);
+ if (!part) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ part->memfd = d->memfd.fd;
+ part->size = d->memfd.size;
+ part->sealed = true;
+
+ idx += d->memfd.size;
+ break;
+ }
+
+ case KDBUS_ITEM_CREDS:
+ /* UID/GID/PID are always valid */
+ m->creds.uid = (uid_t) d->creds.uid;
+ m->creds.gid = (gid_t) d->creds.gid;
+ m->creds.pid = (pid_t) d->creds.pid;
+ m->creds.mask |= (SD_BUS_CREDS_UID|SD_BUS_CREDS_GID|SD_BUS_CREDS_PID) & bus->creds_mask;
+
+ /* The PID starttime/TID might be missing
+ * however, when the data is faked by some
+ * data bus proxy and it lacks that
+ * information about the real client since
+ * SO_PEERCRED is used for that */
+
+ if (d->creds.starttime > 0) {
+ m->creds.pid_starttime = d->creds.starttime / NSEC_PER_USEC;
+ m->creds.mask |= SD_BUS_CREDS_PID_STARTTIME & bus->creds_mask;
+ }
+
+ if (d->creds.tid > 0) {
+ m->creds.tid = (pid_t) d->creds.tid;
+ m->creds.mask |= SD_BUS_CREDS_TID & bus->creds_mask;
+ }
+ break;
+
+ case KDBUS_ITEM_TIMESTAMP:
+ m->realtime = d->timestamp.realtime_ns / NSEC_PER_USEC;
+ m->monotonic = d->timestamp.monotonic_ns / NSEC_PER_USEC;
+ break;
+
+ case KDBUS_ITEM_PID_COMM:
+ m->creds.comm = d->str;
+ m->creds.mask |= SD_BUS_CREDS_COMM & bus->creds_mask;
+ break;
+
+ case KDBUS_ITEM_TID_COMM:
+ m->creds.tid_comm = d->str;
+ m->creds.mask |= SD_BUS_CREDS_TID_COMM & bus->creds_mask;
+ break;
+
+ case KDBUS_ITEM_EXE:
+ m->creds.exe = d->str;
+ m->creds.mask |= SD_BUS_CREDS_EXE & bus->creds_mask;
+ break;
+
+ case KDBUS_ITEM_CMDLINE:
+ m->creds.cmdline = d->str;
+ m->creds.cmdline_size = l;
+ m->creds.mask |= SD_BUS_CREDS_CMDLINE & bus->creds_mask;
+ break;
+
+ case KDBUS_ITEM_CGROUP:
+ m->creds.cgroup = d->str;
+ 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;
+
+ if (!bus->cgroup_root) {
+ r = cg_get_root_path(&bus->cgroup_root);
+ if (r < 0)
+ goto fail;
+ }
+
+ m->creds.cgroup_root = bus->cgroup_root;
+
+ break;
+
+ case KDBUS_ITEM_AUDIT:
+ m->creds.audit_session_id = (uint32_t) d->audit.sessionid;
+ m->creds.audit_login_uid = (uid_t) d->audit.loginuid;
+ m->creds.mask |= (SD_BUS_CREDS_AUDIT_SESSION_ID|SD_BUS_CREDS_AUDIT_LOGIN_UID) & bus->creds_mask;
+ break;
+
+ case KDBUS_ITEM_CAPS:
+ m->creds.capability = d->data;
+ m->creds.capability_size = l;
+ 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;
+ break;
+
+ case KDBUS_ITEM_DST_NAME:
+ if (!service_name_is_valid(d->str))
+ return -EBADMSG;
+
+ destination = d->str;
+ break;
+
+ case KDBUS_ITEM_NAME:
+ if (!service_name_is_valid(d->name.name))
+ return -EBADMSG;
+
+ r = strv_extend(&m->creds.well_known_names, d->name.name);
+ if (r < 0)
+ goto fail;
+ break;
+
+ case KDBUS_ITEM_FDS:
+ case KDBUS_ITEM_SECLABEL:
+ break;
+
+ default:
+ log_debug("Got unknown field from kernel %llu", d->type);
+ }
+ }
+
+ r = bus_message_parse_fields(m);
+ if (r < 0)
+ goto fail;
+
+ /* Override information from the user header with data from the kernel */
+ if (k->src_id == KDBUS_SRC_ID_KERNEL)
+ m->sender = m->creds.unique_name = (char*) "org.freedesktop.DBus";
+ else {
+ snprintf(m->sender_buffer, sizeof(m->sender_buffer), ":1.%llu", (unsigned long long) k->src_id);
+ m->sender = m->creds.unique_name = m->sender_buffer;
+ }
+
+ if (destination)
+ m->destination = destination;
+ else if (k->dst_id == KDBUS_DST_ID_BROADCAST)
+ m->destination = NULL;
+ else if (k->dst_id == KDBUS_DST_ID_NAME)
+ m->destination = bus->unique_name; /* fill in unique name if the well-known name is missing */
+ else {
+ snprintf(m->destination_buffer, sizeof(m->destination_buffer), ":1.%llu", (unsigned long long) k->dst_id);
+ m->destination = m->destination_buffer;
+ }
+
+ /* We take possession of the kmsg struct now */
+ m->kdbus = k;
+ m->release_kdbus = true;
+ m->free_fds = true;
+ fds = NULL;
+
+ bus->rqueue[bus->rqueue_size++] = m;
+
+ return 1;
+
+fail:
+ if (m) {
+ struct bus_body_part *part;
+ unsigned i;
+
+ /* Make sure the memfds are not freed twice */
+ MESSAGE_FOREACH_PART(part, i, m)
+ if (part->memfd >= 0)
+ part->memfd = -1;
+
+ sd_bus_message_unref(m);
+ }
+
+ return r;
+}
+
+int bus_kernel_take_fd(sd_bus *b) {
+ struct kdbus_cmd_hello *hello;
+ struct kdbus_item *item;
+ size_t l = 0, sz;
+ int r;
+
+ assert(b);
+
+ if (b->is_server)
+ return -EINVAL;
+
+ b->use_memfd = 1;
+
+ sz = ALIGN8(offsetof(struct kdbus_cmd_hello, items));
+
+ if (b->fake_creds_valid)
+ sz += ALIGN8(offsetof(struct kdbus_item, creds)) + sizeof(struct kdbus_creds);
+
+ if (b->fake_label) {
+ l = strlen(b->fake_label);
+ sz += ALIGN8(offsetof(struct kdbus_item, str) + l + 1);
+ }
+
+ hello = alloca0(sz);
+ hello->size = sz;
+ hello->conn_flags = b->hello_flags;
+ hello->attach_flags = b->attach_flags;
+ hello->pool_size = KDBUS_POOL_SIZE;
+
+ item = hello->items;
+
+ if (b->fake_creds_valid) {
+ item->size = offsetof(struct kdbus_item, creds) + sizeof(struct kdbus_creds);
+ item->type = KDBUS_ITEM_CREDS;
+ item->creds = b->fake_creds;
+
+ item = KDBUS_ITEM_NEXT(item);
+ }
+
+ if (b->fake_label) {
+ item->size = offsetof(struct kdbus_item, str) + l + 1;
+ memcpy(item->str, b->fake_label, l+1);
+ }
+
+ r = ioctl(b->input_fd, KDBUS_CMD_HELLO, hello);
+ if (r < 0)
+ return -errno;
+
+ if (!b->kdbus_buffer) {
+ b->kdbus_buffer = mmap(NULL, KDBUS_POOL_SIZE, PROT_READ, MAP_SHARED, b->input_fd, 0);
+ if (b->kdbus_buffer == MAP_FAILED) {
+ b->kdbus_buffer = NULL;
+ return -errno;
+ }
+ }
+
+ /* The higher 32bit of both flags fields are considered
+ * 'incompatible flags'. Refuse them all for now. */
+ if (hello->bus_flags > 0xFFFFFFFFULL ||
+ hello->conn_flags > 0xFFFFFFFFULL)
+ return -ENOTSUP;
+
+ if (hello->bloom_size != BLOOM_SIZE)
+ return -ENOTSUP;
+
+ if (asprintf(&b->unique_name, ":1.%llu", (unsigned long long) hello->id) < 0)
+ return -ENOMEM;
+
+ b->unique_id = hello->id;
+
+ b->is_kernel = true;
+ b->bus_client = true;
+ b->can_fds = !!(hello->conn_flags & KDBUS_HELLO_ACCEPT_FD);
+ b->message_version = 2;
+ b->message_endian = BUS_NATIVE_ENDIAN;
+
+ /* the kernel told us the UUID of the underlying bus */
+ memcpy(b->server_id.bytes, hello->id128, sizeof(b->server_id.bytes));
+
+ return bus_start_running(b);
+}
+
+int bus_kernel_connect(sd_bus *b) {
+ assert(b);
+ assert(b->input_fd < 0);
+ assert(b->output_fd < 0);
+ assert(b->kernel);
+
+ if (b->is_server)
+ return -EINVAL;
+
+ b->input_fd = open(b->kernel, O_RDWR|O_NOCTTY|O_CLOEXEC);
+ if (b->input_fd < 0)
+ return -errno;
+
+ b->output_fd = b->input_fd;
+
+ return bus_kernel_take_fd(b);
+}
+
+int bus_kernel_write_message(sd_bus *bus, sd_bus_message *m) {
+ int r;
+
+ assert(bus);
+ assert(m);
+ assert(bus->state == BUS_RUNNING);
+
+ /* If we can't deliver, we want room for the error message */
+ r = bus_rqueue_make_room(bus);
+ if (r < 0)
+ return r;
+
+ r = bus_message_setup_kmsg(bus, m);
+ if (r < 0)
+ return r;
+
+ r = ioctl(bus->output_fd, KDBUS_CMD_MSG_SEND, m->kdbus);
+ if (r < 0) {
+ _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+ sd_bus_message *reply;
+
+ if (errno == EAGAIN || errno == EINTR)
+ return 0;
+ else if (errno == ENXIO || errno == ESRCH) {
+
+ /* ENXIO: unique name not known
+ * ESRCH: well-known name not known */
+
+ if (m->header->type == SD_BUS_MESSAGE_METHOD_CALL)
+ sd_bus_error_setf(&error, SD_BUS_ERROR_SERVICE_UNKNOWN, "Destination %s not known", m->destination);
+ else {
+ log_debug("Could not deliver message to %s as destination is not known. Ignoring.", m->destination);
+ return 0;
+ }
+
+ } else if (errno == EADDRNOTAVAIL) {
+
+ /* EADDRNOTAVAIL: activation is possible, but turned off in request flags */
+
+ if (m->header->type == SD_BUS_MESSAGE_METHOD_CALL)
+ sd_bus_error_setf(&error, SD_BUS_ERROR_SERVICE_UNKNOWN, "Activation of %s not requested", m->destination);
+ else {
+ log_debug("Could not deliver message to %s as destination is not activated. Ignoring.", m->destination);
+ return 0;
+ }
+ } else
+ return -errno;
+
+ r = bus_message_new_synthetic_error(
+ bus,
+ BUS_MESSAGE_COOKIE(m),
+ &error,
+ &reply);
+
+ if (r < 0)
+ return r;
+
+ r = bus_seal_synthetic_message(bus, reply);
+ if (r < 0)
+ return r;
+
+ bus->rqueue[bus->rqueue_size++] = reply;
+
+ return 0;
+ }
+
+ return 1;
+}
+
+static void close_kdbus_msg(sd_bus *bus, struct kdbus_msg *k) {
+ uint64_t off;
+ struct kdbus_item *d;
+
+ assert(bus);
+ assert(k);
+
+ off = (uint8_t *)k - (uint8_t *)bus->kdbus_buffer;
+ ioctl(bus->input_fd, KDBUS_CMD_FREE, &off);
+
+ KDBUS_ITEM_FOREACH(d, k, items) {
+
+ if (d->type == KDBUS_ITEM_FDS)
+ close_many(d->fds, (d->size - offsetof(struct kdbus_item, fds)) / sizeof(int));
+ else if (d->type == KDBUS_ITEM_PAYLOAD_MEMFD)
+ close_nointr_nofail(d->memfd.fd);
+ }
+}
+
+static int push_name_owner_changed(sd_bus *bus, const char *name, const char *old_owner, const char *new_owner) {
+ _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+ int r;
+
+ assert(bus);
+
+ r = sd_bus_message_new_signal(
+ bus,
+ "/org/freedesktop/DBus",
+ "org.freedesktop.DBus",
+ "NameOwnerChanged",
+ &m);
+ if (r < 0)
+ return r;
+
+ r = sd_bus_message_append(m, "sss", name, old_owner, new_owner);
+ if (r < 0)
+ return r;
+
+ m->sender = "org.freedesktop.DBus";
+
+ r = bus_seal_synthetic_message(bus, m);
+ if (r < 0)
+ return r;
+
+ bus->rqueue[bus->rqueue_size++] = m;
+ m = NULL;
+
+ return 1;
+}
+
+static int translate_name_change(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item *d) {
+ char new_owner[UNIQUE_NAME_MAX], old_owner[UNIQUE_NAME_MAX];
+
+ assert(bus);
+ assert(k);
+ assert(d);
+
+ if (d->type == KDBUS_ITEM_NAME_ADD || (d->name_change.old.flags & (KDBUS_NAME_IN_QUEUE|KDBUS_NAME_ACTIVATOR)))
+ old_owner[0] = 0;
+ else
+ sprintf(old_owner, ":1.%llu", (unsigned long long) d->name_change.old.id);
+
+ if (d->type == KDBUS_ITEM_NAME_REMOVE || (d->name_change.new.flags & (KDBUS_NAME_IN_QUEUE|KDBUS_NAME_ACTIVATOR))) {
+
+ if (isempty(old_owner))
+ return 0;
+
+ new_owner[0] = 0;
+ } else
+ sprintf(new_owner, ":1.%llu", (unsigned long long) d->name_change.new.id);
+
+ return push_name_owner_changed(bus, d->name_change.name, old_owner, new_owner);
+}
+
+static int translate_id_change(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item *d) {
+ char owner[UNIQUE_NAME_MAX];
+
+ assert(bus);
+ assert(k);
+ assert(d);
+
+ sprintf(owner, ":1.%llu", d->id_change.id);
+
+ return push_name_owner_changed(
+ bus, owner,
+ d->type == KDBUS_ITEM_ID_ADD ? NULL : owner,
+ d->type == KDBUS_ITEM_ID_ADD ? owner : NULL);
+}
+
+static int translate_reply(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item *d) {
+ _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+ int r;
+
+ assert(bus);
+ assert(k);
+ assert(d);
+
+ r = bus_message_new_synthetic_error(
+ bus,
+ k->cookie_reply,
+ d->type == KDBUS_ITEM_REPLY_TIMEOUT ?
+ &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_NO_REPLY, "Method call timed out") :
+ &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_NO_REPLY, "Method call peer died"),
+ &m);
+ if (r < 0)
+ return r;
+
+ m->sender = "org.freedesktop.DBus";
+
+ r = bus_seal_synthetic_message(bus, m);
+ if (r < 0)
+ return r;
+
+ bus->rqueue[bus->rqueue_size++] = m;
+ m = NULL;
+
+ return 1;
+}
+
+static int bus_kernel_translate_message(sd_bus *bus, struct kdbus_msg *k) {
+ struct kdbus_item *d, *found = NULL;
+
+ static int (* const translate[])(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item *d) = {
+ [KDBUS_ITEM_NAME_ADD - _KDBUS_ITEM_KERNEL_BASE] = translate_name_change,
+ [KDBUS_ITEM_NAME_REMOVE - _KDBUS_ITEM_KERNEL_BASE] = translate_name_change,
+ [KDBUS_ITEM_NAME_CHANGE - _KDBUS_ITEM_KERNEL_BASE] = translate_name_change,
+
+ [KDBUS_ITEM_ID_ADD - _KDBUS_ITEM_KERNEL_BASE] = translate_id_change,
+ [KDBUS_ITEM_ID_REMOVE - _KDBUS_ITEM_KERNEL_BASE] = translate_id_change,
+
+ [KDBUS_ITEM_REPLY_TIMEOUT - _KDBUS_ITEM_KERNEL_BASE] = translate_reply,
+ [KDBUS_ITEM_REPLY_DEAD - _KDBUS_ITEM_KERNEL_BASE] = translate_reply,
+ };
+
+ assert(bus);
+ assert(k);
+ assert(k->payload_type == KDBUS_PAYLOAD_KERNEL);
+
+ KDBUS_ITEM_FOREACH(d, k, items) {
+ if (d->type >= _KDBUS_ITEM_KERNEL_BASE && d->type < _KDBUS_ITEM_KERNEL_BASE + ELEMENTSOF(translate)) {
+ if (found)
+ return -EBADMSG;
+ found = d;
+ } else
+ log_debug("Got unknown field from kernel %llu", d->type);
+ }
+
+ if (!found) {
+ log_debug("Didn't find a kernel message to translate.");
+ return 0;
+ }
+
+ return translate[found->type - _KDBUS_ITEM_KERNEL_BASE](bus, k, found);
+}
+
+int bus_kernel_read_message(sd_bus *bus) {
+ struct kdbus_cmd_recv recv = {};
+ struct kdbus_msg *k;
+ int r;
+
+ assert(bus);
+
+ r = bus_rqueue_make_room(bus);
+ if (r < 0)
+ return r;
+
+ r = ioctl(bus->input_fd, KDBUS_CMD_MSG_RECV, &recv);
+ if (r < 0) {
+ if (errno == EAGAIN)
+ return 0;
+
+ return -errno;
+ }
+ k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + recv.offset);
+
+ if (k->payload_type == KDBUS_PAYLOAD_DBUS) {
+ r = bus_kernel_make_message(bus, k);
+
+ /* Anybody can send us invalid messages, let's just drop them. */
+ if (r == -EBADMSG || r == -EPROTOTYPE) {
+ log_debug("Ignoring invalid message: %s", strerror(-r));
+ r = 0;
+ }
+
+ } else if (k->payload_type == KDBUS_PAYLOAD_KERNEL)
+ r = bus_kernel_translate_message(bus, k);
+ else
+ r = 0;
+
+ if (r <= 0)
+ close_kdbus_msg(bus, k);
+
+ return r < 0 ? r : 1;
+}
+
+int bus_kernel_pop_memfd(sd_bus *bus, void **address, size_t *mapped, size_t *allocated) {
+ struct memfd_cache *c;
+ int fd;
+
+ assert(address);
+ assert(mapped);
+ assert(allocated);
+
+ if (!bus || !bus->is_kernel)
+ return -ENOTSUP;
+
+ assert_se(pthread_mutex_lock(&bus->memfd_cache_mutex) >= 0);
+
+ if (bus->n_memfd_cache <= 0) {
+ struct kdbus_cmd_memfd_make cmd = {
+ .size = sizeof(struct kdbus_cmd_memfd_make),
+ };
+ int r;
+
+ assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
+
+ r = ioctl(bus->input_fd, KDBUS_CMD_MEMFD_NEW, &cmd);
+ if (r < 0)
+ return -errno;
+
+ *address = NULL;
+ *mapped = 0;
+ *allocated = 0;
+ return cmd.fd;
+ }
+
+ c = &bus->memfd_cache[--bus->n_memfd_cache];
+
+ assert(c->fd >= 0);
+ assert(c->mapped == 0 || c->address);
+
+ *address = c->address;
+ *mapped = c->mapped;
+ *allocated = c->allocated;
+ fd = c->fd;
+
+ assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
+
+ return fd;
+}
+
+static void close_and_munmap(int fd, void *address, size_t size) {
+ if (size > 0)
+ assert_se(munmap(address, PAGE_ALIGN(size)) >= 0);
+
+ close_nointr_nofail(fd);
+}
+
+void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t mapped, size_t allocated) {
+ struct memfd_cache *c;
+ uint64_t max_mapped = PAGE_ALIGN(MEMFD_CACHE_ITEM_SIZE_MAX);
+
+ assert(fd >= 0);
+ assert(mapped == 0 || address);
+
+ if (!bus || !bus->is_kernel) {
+ close_and_munmap(fd, address, mapped);
+ return;
+ }
+
+ assert_se(pthread_mutex_lock(&bus->memfd_cache_mutex) >= 0);
+
+ if (bus->n_memfd_cache >= ELEMENTSOF(bus->memfd_cache)) {
+ assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
+
+ close_and_munmap(fd, address, mapped);
+ return;
+ }
+
+ c = &bus->memfd_cache[bus->n_memfd_cache++];
+ c->fd = fd;
+ c->address = address;
+
+ /* If overly long, let's return a bit to the OS */
+ if (mapped > max_mapped) {
+ assert_se(ioctl(fd, KDBUS_CMD_MEMFD_SIZE_SET, &max_mapped) >= 0);
+ assert_se(munmap((uint8_t*) address + max_mapped, PAGE_ALIGN(mapped - max_mapped)) >= 0);
+ c->mapped = c->allocated = max_mapped;
+ } else {
+ c->mapped = mapped;
+ c->allocated = allocated;
+ }
+
+ assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
+}
+
+void bus_kernel_flush_memfd(sd_bus *b) {
+ unsigned i;
+
+ assert(b);
+
+ for (i = 0; i < b->n_memfd_cache; i++)
+ close_and_munmap(b->memfd_cache[i].fd, b->memfd_cache[i].address, b->memfd_cache[i].mapped);
+}
+
+int kdbus_translate_request_name_flags(uint64_t flags, uint64_t *kdbus_flags) {
+ uint64_t f = 0;
+
+ assert(kdbus_flags);
+
+ if (flags & SD_BUS_NAME_ALLOW_REPLACEMENT)
+ f |= KDBUS_NAME_ALLOW_REPLACEMENT;
+
+ if (flags & SD_BUS_NAME_REPLACE_EXISTING)
+ f |= KDBUS_NAME_REPLACE_EXISTING;
+
+ if (flags & SD_BUS_NAME_QUEUE)
+ f |= KDBUS_NAME_QUEUE;
+
+ *kdbus_flags = f;
+ return 0;
+}
+
+int kdbus_translate_attach_flags(uint64_t mask, uint64_t *kdbus_mask) {
+ uint64_t m = 0;
+
+ assert(kdbus_mask);
+
+ if (mask & (SD_BUS_CREDS_UID|SD_BUS_CREDS_GID|SD_BUS_CREDS_PID|SD_BUS_CREDS_PID_STARTTIME|SD_BUS_CREDS_TID))
+ m |= KDBUS_ATTACH_CREDS;
+
+ if (mask & (SD_BUS_CREDS_COMM|SD_BUS_CREDS_TID_COMM))
+ m |= KDBUS_ATTACH_COMM;
+
+ if (mask & SD_BUS_CREDS_EXE)
+ m |= KDBUS_ATTACH_EXE;
+
+ if (mask & SD_BUS_CREDS_CMDLINE)
+ m |= KDBUS_ATTACH_CMDLINE;
+
+ 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))
+ m |= KDBUS_ATTACH_CGROUP;
+
+ if (mask & (SD_BUS_CREDS_EFFECTIVE_CAPS|SD_BUS_CREDS_PERMITTED_CAPS|SD_BUS_CREDS_INHERITABLE_CAPS|SD_BUS_CREDS_BOUNDING_CAPS))
+ m |= KDBUS_ATTACH_CAPS;
+
+ if (mask & SD_BUS_CREDS_SELINUX_CONTEXT)
+ m |= KDBUS_ATTACH_SECLABEL;
+
+ if (mask & (SD_BUS_CREDS_AUDIT_SESSION_ID|SD_BUS_CREDS_AUDIT_LOGIN_UID))
+ m |= KDBUS_ATTACH_AUDIT;
+
+ if (mask & SD_BUS_CREDS_WELL_KNOWN_NAMES)
+ m |= KDBUS_ATTACH_NAMES;
+
+ *kdbus_mask = m;
+ return 0;
+}
+
+int bus_kernel_create_bus(const char *name, bool world, char **s) {
+ struct kdbus_cmd_make *make;
+ struct kdbus_item *n;
+ int fd;
+
+ assert(name);
+ assert(s);
+
+ fd = open("/dev/kdbus/control", O_RDWR|O_NOCTTY|O_CLOEXEC);
+ if (fd < 0)
+ return -errno;
+
+ make = alloca0(ALIGN8(offsetof(struct kdbus_cmd_make, items) +
+ offsetof(struct kdbus_item, data64) + sizeof(uint64_t) +
+ offsetof(struct kdbus_item, str) +
+ DECIMAL_STR_MAX(uid_t) + 1 + strlen(name) + 1));
+
+ make->size = offsetof(struct kdbus_cmd_make, items);
+
+ n = make->items;
+ n->size = offsetof(struct kdbus_item, data64) + sizeof(uint64_t);
+ n->type = KDBUS_ITEM_BLOOM_SIZE;
+ n->data64[0] = BLOOM_SIZE;
+ assert_cc(BLOOM_SIZE % 8 == 0);
+ make->size += ALIGN8(n->size);
+
+ n = KDBUS_ITEM_NEXT(n);
+ sprintf(n->str, "%lu-%s", (unsigned long) getuid(), name);
+ n->size = offsetof(struct kdbus_item, str) + strlen(n->str) + 1;
+ n->type = KDBUS_ITEM_MAKE_NAME;
+ make->size += ALIGN8(n->size);
+
+ make->flags = KDBUS_MAKE_POLICY_OPEN | (world ? KDBUS_MAKE_ACCESS_WORLD : 0);
+
+ if (ioctl(fd, KDBUS_CMD_BUS_MAKE, make) < 0) {
+ close_nointr_nofail(fd);
+ return -errno;
+ }
+
+ /* The higher 32bit of the flags field are considered
+ * 'incompatible flags'. Refuse them all for now. */
+ if (make->flags > 0xFFFFFFFFULL) {
+ close_nointr_nofail(fd);
+ return -ENOTSUP;
+ }
+
+ if (s) {
+ char *p;
+
+ p = strjoin("/dev/kdbus/", n->str, "/bus", NULL);
+ if (!p) {
+ close_nointr_nofail(fd);
+ return -ENOMEM;
+ }
+
+ *s = p;
+ }
+
+ return fd;
+}
+
+int bus_kernel_create_starter(const char *bus, const char *name) {
+ struct kdbus_cmd_hello *hello;
+ struct kdbus_item *n;
+ char *p;
+ int fd;
+
+ assert(bus);
+ assert(name);
+
+ p = alloca(sizeof("/dev/kdbus/") - 1 + DECIMAL_STR_MAX(uid_t) + 1 + strlen(bus) + sizeof("/bus"));
+ sprintf(p, "/dev/kdbus/%lu-%s/bus", (unsigned long) getuid(), bus);
+
+ fd = open(p, O_RDWR|O_NOCTTY|O_CLOEXEC);
+ if (fd < 0)
+ return -errno;
+
+ hello = alloca0(ALIGN8(offsetof(struct kdbus_cmd_hello, items) +
+ offsetof(struct kdbus_item, str) +
+ strlen(name) + 1));
+
+ n = hello->items;
+ strcpy(n->str, name);
+ n->size = offsetof(struct kdbus_item, str) + strlen(n->str) + 1;
+ n->type = KDBUS_ITEM_NAME;
+
+ hello->size = ALIGN8(offsetof(struct kdbus_cmd_hello, items) + n->size);
+ hello->conn_flags = KDBUS_HELLO_ACTIVATOR;
+ hello->pool_size = KDBUS_POOL_SIZE;
+
+ if (ioctl(fd, KDBUS_CMD_HELLO, hello) < 0) {
+ close_nointr_nofail(fd);
+ return -errno;
+ }
+
+ /* The higher 32bit of both flags fields are considered
+ * 'incompatible flags'. Refuse them all for now. */
+ if (hello->bus_flags > 0xFFFFFFFFULL ||
+ hello->conn_flags > 0xFFFFFFFFULL) {
+ close_nointr_nofail(fd);
+ return -ENOTSUP;
+ }
+
+ if (hello->bloom_size != BLOOM_SIZE) {
+ close_nointr_nofail(fd);
+ return -ENOTSUP;
+ }
+
+ return fd;
+}
+
+int bus_kernel_create_namespace(const char *name, char **s) {
+ struct kdbus_cmd_make *make;
+ struct kdbus_item *n;
+ int fd;
+
+ assert(name);
+ assert(s);
+
+ fd = open("/dev/kdbus/control", O_RDWR|O_NOCTTY|O_CLOEXEC);
+ if (fd < 0)
+ return -errno;
+
+ make = alloca0(ALIGN8(offsetof(struct kdbus_cmd_make, items) +
+ offsetof(struct kdbus_item, str) +
+ strlen(name) + 1));
+
+ n = make->items;
+ strcpy(n->str, name);
+ n->size = offsetof(struct kdbus_item, str) + strlen(n->str) + 1;
+ n->type = KDBUS_ITEM_MAKE_NAME;
+
+ make->size = ALIGN8(offsetof(struct kdbus_cmd_make, items) + n->size);
+ make->flags = KDBUS_MAKE_POLICY_OPEN | KDBUS_MAKE_ACCESS_WORLD;
+
+ if (ioctl(fd, KDBUS_CMD_NS_MAKE, make) < 0) {
+ close_nointr_nofail(fd);
+ return -errno;
+ }
+
+ /* The higher 32bit of the flags field are considered
+ * 'incompatible flags'. Refuse them all for now. */
+ if (make->flags > 0xFFFFFFFFULL) {
+ close_nointr_nofail(fd);
+ return -ENOTSUP;
+ }
+
+ if (s) {
+ char *p;
+
+ p = strappend("/dev/kdbus/ns/", name);
+ if (!p) {
+ close_nointr_nofail(fd);
+ return -ENOMEM;
+ }
+
+ *s = p;
+ }
+
+ return fd;
+}
+
+int bus_kernel_create_monitor(const char *bus) {
+ struct kdbus_cmd_hello *hello;
+ char *p;
+ int fd;
+
+ assert(bus);
+
+ p = alloca(sizeof("/dev/kdbus/") - 1 + DECIMAL_STR_MAX(uid_t) + 1 + strlen(bus) + sizeof("/bus"));
+ sprintf(p, "/dev/kdbus/%lu-%s/bus", (unsigned long) getuid(), bus);
+
+ fd = open(p, O_RDWR|O_NOCTTY|O_CLOEXEC);
+ if (fd < 0)
+ return -errno;
+
+ hello = alloca0(sizeof(struct kdbus_cmd_hello));
+ hello->size = sizeof(struct kdbus_cmd_hello);
+ hello->conn_flags = KDBUS_HELLO_ACTIVATOR;
+ hello->pool_size = KDBUS_POOL_SIZE;
+
+ if (ioctl(fd, KDBUS_CMD_HELLO, hello) < 0) {
+ close_nointr_nofail(fd);
+ return -errno;
+ }
+
+ /* The higher 32bit of both flags fields are considered
+ * 'incompatible flags'. Refuse them all for now. */
+ if (hello->bus_flags > 0xFFFFFFFFULL ||
+ hello->conn_flags > 0xFFFFFFFFULL) {
+ close_nointr_nofail(fd);
+ return -ENOTSUP;
+ }
+
+ return fd;
+}
+
+int bus_kernel_try_close(sd_bus *bus) {
+ assert(bus);
+ assert(bus->is_kernel);
+
+ if (ioctl(bus->input_fd, KDBUS_CMD_BYEBYE) < 0)
+ return -errno;
+
+ return 0;
+}