libsystemd-bus: rename to libsystemd

Documentation was updated to refer to either 'libsystemd' or 'sd-bus' in place
of libsystemd-bus.

1 files changed, 1345 insertions, 0 deletions

diff --git a/src/libsystemd/bus-kernel.c b/src/libsystemd/bus-kernel.c
new file mode 100644
index 0000000000..e8f4c58110
--- /dev/null
+++ b/src/libsystemd/bus-kernel.c
@@ -0,0 +1,1345 @@
+/*-*- 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;
+}
+
+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);
+}
+
+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_read_message(sd_bus *bus) {
+        struct kdbus_msg *k;
+        uint64_t off;
+        int r;
+
+        assert(bus);
+
+        r = bus_rqueue_make_room(bus);
+        if (r < 0)
+                return r;
+
+        r = ioctl(bus->input_fd, KDBUS_CMD_MSG_RECV, &off);
+        if (r < 0) {
+                if (errno == EAGAIN)
+                        return 0;
+
+                return -errno;
+        }
+        k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + off);
+
+        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) {
+                int r;
+
+                assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0);
+
+                r = ioctl(bus->input_fd, KDBUS_CMD_MEMFD_NEW, &fd);
+                if (r < 0)
+                        return -errno;
+
+                *address = NULL;
+                *mapped = 0;
+                *allocated = 0;
+                return 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;
+}