/*** 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 <sys/prctl.h> /* When we include libgen.h because we need dirname() we immediately * undefine basename() since libgen.h defines it as a macro to the POSIX * version which is really broken. We prefer GNU basename(). */ #include <libgen.h> #undef basename #include "alloc-util.h" #include "bus-bloom.h" #include "bus-internal.h" #include "bus-kernel.h" #include "bus-label.h" #include "bus-message.h" #include "bus-util.h" #include "capability-util.h" #include "fd-util.h" #include "fileio.h" #include "formats-util.h" #include "memfd-util.h" #include "parse-util.h" #include "stdio-util.h" #include "string-util.h" #include "strv.h" #include "user-util.h" #include "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 start, 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.start = start; (*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 struct kdbus_bloom_filter *append_bloom(struct kdbus_item **d, size_t length) { struct kdbus_item *i; assert(d); i = ALIGN8_PTR(*d); i->size = offsetof(struct kdbus_item, bloom_filter) + offsetof(struct kdbus_bloom_filter, data) + length; i->type = KDBUS_ITEM_BLOOM_FILTER; *d = (struct kdbus_item *) ((uint8_t*) i + i->size); return &i->bloom_filter; } 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 void add_bloom_arg(void *data, size_t size, unsigned n_hash, unsigned i, const char *t) { char buf[sizeof("arg")-1 + 2 + sizeof("-slash-prefix")]; char *e; assert(data); assert(size > 0); assert(i < 64); assert(t); 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(data, size, n_hash, buf, t); strcpy(e, "-dot-prefix"); bloom_add_prefixes(data, size, n_hash, buf, t, '.'); strcpy(e, "-slash-prefix"); bloom_add_prefixes(data, size, n_hash, buf, t, '/'); } static void add_bloom_arg_has(void *data, size_t size, unsigned n_hash, unsigned i, const char *t) { char buf[sizeof("arg")-1 + 2 + sizeof("-has")]; char *e; assert(data); assert(size > 0); assert(i < 64); assert(t); e = stpcpy(buf, "arg"); if (i < 10) *(e++) = '0' + (char) i; else { *(e++) = '0' + (char) (i / 10); *(e++) = '0' + (char) (i % 10); } strcpy(e, "-has"); bloom_add_pair(data, size, n_hash, buf, t); } static int bus_message_setup_bloom(sd_bus_message *m, struct kdbus_bloom_filter *bloom) { void *data; unsigned i; int r; assert(m); assert(bloom); data = bloom->data; memzero(data, m->bus->bloom_size); bloom->generation = 0; bloom_add_pair(data, m->bus->bloom_size, m->bus->bloom_n_hash, "message-type", bus_message_type_to_string(m->header->type)); if (m->interface) bloom_add_pair(data, m->bus->bloom_size, m->bus->bloom_n_hash, "interface", m->interface); if (m->member) bloom_add_pair(data, m->bus->bloom_size, m->bus->bloom_n_hash, "member", m->member); if (m->path) { bloom_add_pair(data, m->bus->bloom_size, m->bus->bloom_n_hash, "path", m->path); bloom_add_pair(data, m->bus->bloom_size, m->bus->bloom_n_hash, "path-slash-prefix", m->path); bloom_add_prefixes(data, m->bus->bloom_size, m->bus->bloom_n_hash, "path-slash-prefix", m->path, '/'); } r = sd_bus_message_rewind(m, true); if (r < 0) return r; for (i = 0; i < 64; i++) { const char *t, *contents; char type; r = sd_bus_message_peek_type(m, &type, &contents); if (r < 0) return r; if (IN_SET(type, SD_BUS_TYPE_STRING, SD_BUS_TYPE_OBJECT_PATH, SD_BUS_TYPE_SIGNATURE)) { /* The bloom filter includes simple strings of any kind */ r = sd_bus_message_read_basic(m, type, &t); if (r < 0) return r; add_bloom_arg(data, m->bus->bloom_size, m->bus->bloom_n_hash, i, t); } if (type == SD_BUS_TYPE_ARRAY && STR_IN_SET(contents, "s", "o", "g")) { /* As well as array of simple strings of any kinds */ r = sd_bus_message_enter_container(m, type, contents); if (r < 0) return r; while ((r = sd_bus_message_read_basic(m, contents[0], &t)) > 0) add_bloom_arg_has(data, m->bus->bloom_size, m->bus->bloom_n_hash, i, t); if (r < 0) return r; r = sd_bus_message_exit_container(m); if (r < 0) return r; } else /* Stop adding to bloom filter as soon as we * run into the first argument we cannot add * to it. */ break; } return 0; } static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) { struct bus_body_part *part; struct kdbus_item *d; const char *destination; bool well_known = false; uint64_t dst_id; size_t sz, dl; unsigned i; int r; assert(b); assert(m); assert(m->sealed); /* We put this together only once, if this message is reused * we reuse the earlier-built version */ if (m->kdbus) return 0; destination = m->destination ?: m->destination_ptr; if (destination) { r = bus_kernel_parse_unique_name(destination, &dst_id); if (r < 0) return r; if (r == 0) { well_known = true; /* verify_destination_id will usually be 0, which makes the kernel * driver only look at the provided well-known name. Otherwise, * the kernel will make sure the provided destination id matches * the owner of the provided well-known-name, and fail if they * differ. Currently, this is only needed for bus-proxyd. */ dst_id = m->verify_destination_id; } } else dst_id = KDBUS_DST_ID_BROADCAST; sz = offsetof(struct kdbus_msg, items); /* Add in fixed header, fields header and payload */ sz += (1 + m->n_body_parts) * ALIGN8(offsetof(struct kdbus_item, vec) + MAX(sizeof(struct kdbus_vec), sizeof(struct kdbus_memfd))); /* Add space for bloom filter */ sz += ALIGN8(offsetof(struct kdbus_item, bloom_filter) + offsetof(struct kdbus_bloom_filter, data) + m->bus->bloom_size); /* Add in well-known destination header */ if (well_known) { dl = strlen(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; memzero(m->kdbus, sz); m->kdbus->flags = ((m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED) ? 0 : KDBUS_MSG_EXPECT_REPLY) | ((m->header->flags & BUS_MESSAGE_NO_AUTO_START) ? KDBUS_MSG_NO_AUTO_START : 0) | ((m->header->type == SD_BUS_MESSAGE_SIGNAL) ? KDBUS_MSG_SIGNAL : 0); m->kdbus->dst_id = dst_id; m->kdbus->payload_type = KDBUS_PAYLOAD_DBUS; m->kdbus->cookie = m->header->dbus2.cookie; m->kdbus->priority = m->priority; if (m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED) m->kdbus->cookie_reply = m->reply_cookie; else { struct timespec now; assert_se(clock_gettime(CLOCK_MONOTONIC_COARSE, &now) == 0); m->kdbus->timeout_ns = now.tv_sec * NSEC_PER_SEC + now.tv_nsec + m->timeout * NSEC_PER_USEC; } d = m->kdbus->items; if (well_known) append_destination(&d, 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 && 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->memfd_offset, 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->header->type == SD_BUS_MESSAGE_SIGNAL) { struct kdbus_bloom_filter *bloom; bloom = append_bloom(&d, m->bus->bloom_size); r = bus_message_setup_bloom(m, bloom); 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 void unset_memfds(struct sd_bus_message *m) { struct bus_body_part *part; unsigned i; assert(m); /* Make sure the memfds are not freed twice */ MESSAGE_FOREACH_PART(part, i, m) if (part->memfd >= 0) part->memfd = -1; } static void message_set_timestamp(sd_bus *bus, sd_bus_message *m, const struct kdbus_timestamp *ts) { assert(bus); assert(m); if (!ts) return; if (!(bus->attach_flags & KDBUS_ATTACH_TIMESTAMP)) return; m->realtime = ts->realtime_ns / NSEC_PER_USEC; m->monotonic = ts->monotonic_ns / NSEC_PER_USEC; m->seqnum = ts->seqnum; } 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 *header = NULL; void *footer = NULL; size_t header_size = 0, footer_size = 0; size_t n_bytes = 0, idx = 0; const char *destination = NULL, *seclabel = NULL; bool last_was_memfd = false; 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 (!header) { header = (struct bus_header*)((uint8_t*) k + d->vec.offset); header_size = d->vec.size; } footer = (uint8_t*) k + d->vec.offset; footer_size = d->vec.size; n_bytes += d->vec.size; last_was_memfd = false; break; case KDBUS_ITEM_PAYLOAD_MEMFD: if (!header) /* memfd cannot be first part */ return -EBADMSG; n_bytes += d->memfd.size; last_was_memfd = true; 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 (last_was_memfd) /* memfd cannot be last part */ return -EBADMSG; if (!header) return -EBADMSG; if (header_size < sizeof(struct bus_header)) return -EBADMSG; /* on kdbus we only speak native endian gvariant, never dbus1 * marshalling or reverse endian */ if (header->version != 2 || header->endian != BUS_NATIVE_ENDIAN) return -EPROTOTYPE; r = bus_message_from_header( bus, header, header_size, footer, footer_size, n_bytes, fds, n_fds, 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->memfd_offset = d->memfd.start; part->size = d->memfd.size; part->sealed = true; idx += d->memfd.size; break; } case KDBUS_ITEM_PIDS: /* The PID/TID might be missing, when the data * is faked by a bus proxy and it lacks that * information about the real client (since * SO_PEERCRED is used for that). Also kernel * namespacing might make some of this data * unavailable when untranslatable. */ if (d->pids.pid > 0) { m->creds.pid = (pid_t) d->pids.pid; m->creds.mask |= SD_BUS_CREDS_PID & bus->creds_mask; } if (d->pids.tid > 0) { m->creds.tid = (pid_t) d->pids.tid; m->creds.mask |= SD_BUS_CREDS_TID & bus->creds_mask; } if (d->pids.ppid > 0) { m->creds.ppid = (pid_t) d->pids.ppid; m->creds.mask |= SD_BUS_CREDS_PPID & bus->creds_mask; } else if (d->pids.pid == 1) { m->creds.ppid = 0; m->creds.mask |= SD_BUS_CREDS_PPID & bus->creds_mask; } break; case KDBUS_ITEM_CREDS: /* EUID/SUID/FSUID/EGID/SGID/FSGID might be * missing too (see above). */ if ((uid_t) d->creds.uid != UID_INVALID) { m->creds.uid = (uid_t) d->creds.uid; m->creds.mask |= SD_BUS_CREDS_UID & bus->creds_mask; } if ((uid_t) d->creds.euid != UID_INVALID) { m->creds.euid = (uid_t) d->creds.euid; m->creds.mask |= SD_BUS_CREDS_EUID & bus->creds_mask; } if ((uid_t) d->creds.suid != UID_INVALID) { m->creds.suid = (uid_t) d->creds.suid; m->creds.mask |= SD_BUS_CREDS_SUID & bus->creds_mask; } if ((uid_t) d->creds.fsuid != UID_INVALID) { m->creds.fsuid = (uid_t) d->creds.fsuid; m->creds.mask |= SD_BUS_CREDS_FSUID & bus->creds_mask; } if ((gid_t) d->creds.gid != GID_INVALID) { m->creds.gid = (gid_t) d->creds.gid; m->creds.mask |= SD_BUS_CREDS_GID & bus->creds_mask; } if ((gid_t) d->creds.egid != GID_INVALID) { m->creds.egid = (gid_t) d->creds.egid; m->creds.mask |= SD_BUS_CREDS_EGID & bus->creds_mask; } if ((gid_t) d->creds.sgid != GID_INVALID) { m->creds.sgid = (gid_t) d->creds.sgid; m->creds.mask |= SD_BUS_CREDS_SGID & bus->creds_mask; } if ((gid_t) d->creds.fsgid != GID_INVALID) { m->creds.fsgid = (gid_t) d->creds.fsgid; m->creds.mask |= SD_BUS_CREDS_FSGID & bus->creds_mask; } break; case KDBUS_ITEM_TIMESTAMP: message_set_timestamp(bus, m, &d->timestamp); 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; r = bus_get_root_path(bus); 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.mask |= SD_BUS_CREDS_AUDIT_SESSION_ID & bus->creds_mask; m->creds.audit_login_uid = (uid_t) d->audit.loginuid; m->creds.mask |= SD_BUS_CREDS_AUDIT_LOGIN_UID & bus->creds_mask; break; case KDBUS_ITEM_CAPS: if (d->caps.last_cap != cap_last_cap() || d->size - offsetof(struct kdbus_item, caps.caps) < DIV_ROUND_UP(d->caps.last_cap, 32U) * 4 * 4) { r = -EBADMSG; goto fail; } m->creds.capability = d->caps.caps; 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)) { r = -EBADMSG; goto fail; } destination = d->str; break; case KDBUS_ITEM_OWNED_NAME: if (!service_name_is_valid(d->name.name)) { r = -EBADMSG; goto fail; } if (bus->creds_mask & SD_BUS_CREDS_WELL_KNOWN_NAMES) { char **wkn; size_t n; /* We just extend the array here, but * do not allocate the strings inside * of it, instead we just point to our * buffer directly. */ n = strv_length(m->creds.well_known_names); wkn = realloc(m->creds.well_known_names, (n + 2) * sizeof(char*)); if (!wkn) { r = -ENOMEM; goto fail; } wkn[n] = d->name.name; wkn[n+1] = NULL; m->creds.well_known_names = wkn; m->creds.mask |= SD_BUS_CREDS_WELL_KNOWN_NAMES; } break; case KDBUS_ITEM_CONN_DESCRIPTION: m->creds.description = d->str; m->creds.mask |= SD_BUS_CREDS_DESCRIPTION & bus->creds_mask; break; case KDBUS_ITEM_AUXGROUPS: if (bus->creds_mask & SD_BUS_CREDS_SUPPLEMENTARY_GIDS) { size_t i, n; gid_t *g; n = (d->size - offsetof(struct kdbus_item, data64)) / sizeof(uint64_t); g = new(gid_t, n); if (!g) { r = -ENOMEM; goto fail; } for (i = 0; i < n; i++) g[i] = d->data64[i]; m->creds.supplementary_gids = g; m->creds.n_supplementary_gids = n; m->creds.mask |= SD_BUS_CREDS_SUPPLEMENTARY_GIDS; } break; case KDBUS_ITEM_FDS: case KDBUS_ITEM_SECLABEL: case KDBUS_ITEM_BLOOM_FILTER: break; default: log_debug("Got unknown field from kernel %llu", d->type); } } /* If we requested the list of well-known names to be appended * and the sender had none no item for it will be * attached. However, this does *not* mean that the kernel * didn't want to provide this information to us. Hence, let's * explicitly mark this information as available if it was * requested. */ m->creds.mask |= bus->creds_mask & SD_BUS_CREDS_WELL_KNOWN_NAMES; r = bus_message_parse_fields(m); if (r < 0) goto fail; /* Refuse messages if kdbus and dbus1 cookie doesn't match up */ if ((uint64_t) m->header->dbus2.cookie != k->cookie) { r = -EBADMSG; goto fail; } /* Refuse messages where the reply flag doesn't match up */ if (!(m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED) != !!(k->flags & KDBUS_MSG_EXPECT_REPLY)) { r = -EBADMSG; goto fail; } /* Refuse reply messages where the reply cookie doesn't match up */ if ((m->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED) && m->reply_cookie != k->cookie_reply) { r = -EBADMSG; goto fail; } /* Refuse messages where the autostart flag doesn't match up */ if (!(m->header->flags & BUS_MESSAGE_NO_AUTO_START) != !(k->flags & KDBUS_MSG_NO_AUTO_START)) { r = -EBADMSG; goto fail; } /* Override information from the user header with data from the kernel */ if (k->src_id == KDBUS_SRC_ID_KERNEL) bus_message_set_sender_driver(bus, m); else { xsprintf(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 { xsprintf(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: unset_memfds(m); sd_bus_message_unref(m); return r; } int bus_kernel_take_fd(sd_bus *b) { struct kdbus_bloom_parameter *bloom = NULL; struct kdbus_item *items, *item; struct kdbus_cmd_hello *hello; _cleanup_free_ char *g = NULL; const char *name; size_t l = 0, m = 0, sz; int r; assert(b); if (b->is_server) return -EINVAL; b->use_memfd = 1; if (b->description) { g = bus_label_escape(b->description); if (!g) return -ENOMEM; name = g; } else { char pr[17] = {}; /* If no name is explicitly set, we'll include a hint * indicating the library implementation, a hint which * kind of bus this is and the thread name */ assert_se(prctl(PR_GET_NAME, (unsigned long) pr) >= 0); if (isempty(pr)) { name = b->is_system ? "sd-system" : b->is_user ? "sd-user" : "sd"; } else { _cleanup_free_ char *e = NULL; e = bus_label_escape(pr); if (!e) return -ENOMEM; g = strappend(b->is_system ? "sd-system-" : b->is_user ? "sd-user-" : "sd-", e); if (!g) return -ENOMEM; name = g; } b->description = bus_label_unescape(name); if (!b->description) return -ENOMEM; } m = strlen(name); sz = ALIGN8(offsetof(struct kdbus_cmd_hello, items)) + ALIGN8(offsetof(struct kdbus_item, str) + m + 1); if (b->fake_creds_valid) sz += ALIGN8(offsetof(struct kdbus_item, creds) + sizeof(struct kdbus_creds)); if (b->fake_pids_valid) sz += ALIGN8(offsetof(struct kdbus_item, pids) + sizeof(struct kdbus_pids)); if (b->fake_label) { l = strlen(b->fake_label); sz += ALIGN8(offsetof(struct kdbus_item, str) + l + 1); } hello = alloca0_align(sz, 8); hello->size = sz; hello->flags = b->hello_flags; hello->attach_flags_send = _KDBUS_ATTACH_ANY; hello->attach_flags_recv = b->attach_flags; hello->pool_size = KDBUS_POOL_SIZE; item = hello->items; item->size = offsetof(struct kdbus_item, str) + m + 1; item->type = KDBUS_ITEM_CONN_DESCRIPTION; memcpy(item->str, name, m + 1); item = KDBUS_ITEM_NEXT(item); 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_pids_valid) { item->size = offsetof(struct kdbus_item, pids) + sizeof(struct kdbus_pids); item->type = KDBUS_ITEM_PIDS; item->pids = b->fake_pids; item = KDBUS_ITEM_NEXT(item); } if (b->fake_label) { item->size = offsetof(struct kdbus_item, str) + l + 1; item->type = KDBUS_ITEM_SECLABEL; memcpy(item->str, b->fake_label, l+1); } r = ioctl(b->input_fd, KDBUS_CMD_HELLO, hello); if (r < 0) { if (errno == ENOTTY) /* If the ioctl is not supported we assume that the * API version changed in a major incompatible way, * let's indicate an API incompatibility in this * case. */ return -ESOCKTNOSUPPORT; 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; r = -errno; goto fail; } } /* The higher 32bit of the bus_flags fields are considered * 'incompatible flags'. Refuse them all for now. */ if (hello->bus_flags > 0xFFFFFFFFULL) { r = -ESOCKTNOSUPPORT; goto fail; } /* extract bloom parameters from items */ items = (void*)((uint8_t*)b->kdbus_buffer + hello->offset); KDBUS_FOREACH(item, items, hello->items_size) { switch (item->type) { case KDBUS_ITEM_BLOOM_PARAMETER: bloom = &item->bloom_parameter; break; } } if (!bloom || !bloom_validate_parameters((size_t) bloom->size, (unsigned) bloom->n_hash)) { r = -EOPNOTSUPP; goto fail; } b->bloom_size = (size_t) bloom->size; b->bloom_n_hash = (unsigned) bloom->n_hash; if (asprintf(&b->unique_name, ":1.%llu", (unsigned long long) hello->id) < 0) { r = -ENOMEM; goto fail; } b->unique_id = hello->id; b->is_kernel = true; b->bus_client = true; b->can_fds = !!(hello->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)); /* free returned items */ (void) bus_kernel_cmd_free(b, hello->offset); return bus_start_running(b); fail: (void) bus_kernel_cmd_free(b, hello->offset); return r; } 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_cmd_free(sd_bus *bus, uint64_t offset) { struct kdbus_cmd_free cmd = { .size = sizeof(cmd), .offset = offset, }; int r; assert(bus); assert(bus->is_kernel); r = ioctl(bus->input_fd, KDBUS_CMD_FREE, &cmd); if (r < 0) return -errno; return 0; } static void close_kdbus_msg(sd_bus *bus, struct kdbus_msg *k) { struct kdbus_item *d; assert(bus); assert(k); 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) safe_close(d->memfd.fd); } bus_kernel_cmd_free(bus, (uint8_t*) k - (uint8_t*) bus->kdbus_buffer); } int bus_kernel_write_message(sd_bus *bus, sd_bus_message *m, bool hint_sync_call) { struct kdbus_cmd_send cmd = { }; 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; cmd.size = sizeof(cmd); cmd.msg_address = (uintptr_t)m->kdbus; /* If this is a synchronous method call, then let's tell the * kernel, so that it can pass CPU time/scheduling to the * destination for the time, if it wants to. If we * synchronously wait for the result anyway, we won't need CPU * anyway. */ if (hint_sync_call) { m->kdbus->flags |= KDBUS_MSG_EXPECT_REPLY; cmd.flags |= KDBUS_SEND_SYNC_REPLY; } r = ioctl(bus->output_fd, KDBUS_CMD_SEND, &cmd); if (r < 0) { _cleanup_(sd_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; } else if (hint_sync_call) { struct kdbus_msg *k; k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + cmd.reply.offset); assert(k); if (k->payload_type == KDBUS_PAYLOAD_DBUS) { r = bus_kernel_make_message(bus, k); if (r < 0) { close_kdbus_msg(bus, k); /* Anybody can send us invalid messages, let's just drop them. */ if (r == -EBADMSG || r == -EPROTOTYPE) log_debug_errno(r, "Ignoring invalid synchronous reply: %m"); else return r; } } else { log_debug("Ignoring message with unknown payload type %llu.", (unsigned long long) k->payload_type); close_kdbus_msg(bus, k); } } return 1; } static int push_name_owner_changed( sd_bus *bus, const char *name, const char *old_owner, const char *new_owner, const struct kdbus_timestamp *ts) { _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL; int r; assert(bus); r = sd_bus_message_new_signal( bus, &m, "/org/freedesktop/DBus", "org.freedesktop.DBus", "NameOwnerChanged"); if (r < 0) return r; r = sd_bus_message_append(m, "sss", name, old_owner, new_owner); if (r < 0) return r; bus_message_set_sender_driver(bus, m); message_set_timestamp(bus, m, ts); 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, const struct kdbus_msg *k, const struct kdbus_item *d, const struct kdbus_timestamp *ts) { 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_id.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.id); if (d->type == KDBUS_ITEM_NAME_REMOVE || (d->name_change.new_id.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.id); return push_name_owner_changed(bus, d->name_change.name, old_owner, new_owner, ts); } static int translate_id_change( sd_bus *bus, const struct kdbus_msg *k, const struct kdbus_item *d, const struct kdbus_timestamp *ts) { 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, ts); } static int translate_reply( sd_bus *bus, const struct kdbus_msg *k, const struct kdbus_item *d, const struct kdbus_timestamp *ts) { _cleanup_(sd_bus_message_unrefp) 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; message_set_timestamp(bus, m, ts); 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) { static int (* const translate[])(sd_bus *bus, const struct kdbus_msg *k, const struct kdbus_item *d, const struct kdbus_timestamp *ts) = { [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, }; struct kdbus_item *d, *found = NULL; struct kdbus_timestamp *ts = NULL; assert(bus); assert(k); assert(k->payload_type == KDBUS_PAYLOAD_KERNEL); KDBUS_ITEM_FOREACH(d, k, items) { if (d->type == KDBUS_ITEM_TIMESTAMP) ts = &d->timestamp; else 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, ts); } int bus_kernel_read_message(sd_bus *bus, bool hint_priority, int64_t priority) { struct kdbus_cmd_recv recv = { .size = sizeof(recv) }; struct kdbus_msg *k; int r; assert(bus); r = bus_rqueue_make_room(bus); if (r < 0) return r; if (hint_priority) { recv.flags |= KDBUS_RECV_USE_PRIORITY; recv.priority = priority; } r = ioctl(bus->input_fd, KDBUS_CMD_RECV, &recv); if (recv.return_flags & KDBUS_RECV_RETURN_DROPPED_MSGS) log_debug("%s: kdbus reports %" PRIu64 " dropped broadcast messages, ignoring.", strna(bus->description), (uint64_t) recv.dropped_msgs); if (r < 0) { if (errno == EAGAIN) return 0; return -errno; } k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + recv.msg.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_errno(r, "Ignoring invalid message: %m"); r = 0; } if (r <= 0) close_kdbus_msg(bus, k); } else if (k->payload_type == KDBUS_PAYLOAD_KERNEL) { r = bus_kernel_translate_message(bus, k); close_kdbus_msg(bus, k); } else { log_debug("Ignoring message with unknown payload type %llu.", (unsigned long long) k->payload_type); 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 -EOPNOTSUPP; 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 = memfd_new(bus->description); if (r < 0) return r; *address = NULL; *mapped = 0; *allocated = 0; return r; } 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); safe_close(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(memfd_set_size(fd, 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); } uint64_t request_name_flags_to_kdbus(uint64_t flags) { uint64_t f = 0; 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; return f; } uint64_t attach_flags_to_kdbus(uint64_t mask) { uint64_t m = 0; if (mask & (SD_BUS_CREDS_UID|SD_BUS_CREDS_EUID|SD_BUS_CREDS_SUID|SD_BUS_CREDS_FSUID| SD_BUS_CREDS_GID|SD_BUS_CREDS_EGID|SD_BUS_CREDS_SGID|SD_BUS_CREDS_FSGID)) m |= KDBUS_ATTACH_CREDS; if (mask & (SD_BUS_CREDS_PID|SD_BUS_CREDS_TID|SD_BUS_CREDS_PPID)) m |= KDBUS_ATTACH_PIDS; if (mask & SD_BUS_CREDS_COMM) m |= KDBUS_ATTACH_PID_COMM; if (mask & SD_BUS_CREDS_TID_COMM) m |= KDBUS_ATTACH_TID_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; if (mask & SD_BUS_CREDS_DESCRIPTION) m |= KDBUS_ATTACH_CONN_DESCRIPTION; if (mask & SD_BUS_CREDS_SUPPLEMENTARY_GIDS) m |= KDBUS_ATTACH_AUXGROUPS; return m; } int bus_kernel_create_bus(const char *name, bool world, char **s) { struct kdbus_cmd *make; struct kdbus_item *n; size_t l; int fd; assert(name); assert(s); fd = open("/sys/fs/kdbus/control", O_RDWR|O_NOCTTY|O_CLOEXEC); if (fd < 0) return -errno; l = strlen(name); make = alloca0_align(offsetof(struct kdbus_cmd, items) + ALIGN8(offsetof(struct kdbus_item, bloom_parameter) + sizeof(struct kdbus_bloom_parameter)) + ALIGN8(offsetof(struct kdbus_item, data64) + sizeof(uint64_t)) + ALIGN8(offsetof(struct kdbus_item, str) + DECIMAL_STR_MAX(uid_t) + 1 + l + 1), 8); make->size = offsetof(struct kdbus_cmd, items); /* Set the bloom parameters */ n = make->items; n->size = offsetof(struct kdbus_item, bloom_parameter) + sizeof(struct kdbus_bloom_parameter); n->type = KDBUS_ITEM_BLOOM_PARAMETER; n->bloom_parameter.size = DEFAULT_BLOOM_SIZE; n->bloom_parameter.n_hash = DEFAULT_BLOOM_N_HASH; assert_cc(DEFAULT_BLOOM_SIZE > 0); assert_cc(DEFAULT_BLOOM_N_HASH > 0); make->size += ALIGN8(n->size); /* Provide all metadata via bus-owner queries */ n = KDBUS_ITEM_NEXT(n); n->type = KDBUS_ITEM_ATTACH_FLAGS_SEND; n->size = offsetof(struct kdbus_item, data64) + sizeof(uint64_t); n->data64[0] = _KDBUS_ATTACH_ANY; make->size += ALIGN8(n->size); /* Set the a good name */ n = KDBUS_ITEM_NEXT(n); sprintf(n->str, UID_FMT "-%s", 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 = world ? KDBUS_MAKE_ACCESS_WORLD : 0; if (ioctl(fd, KDBUS_CMD_BUS_MAKE, make) < 0) { safe_close(fd); /* Major API change? then the ioctls got shuffled around. */ if (errno == ENOTTY) return -ESOCKTNOSUPPORT; return -errno; } if (s) { char *p; p = strjoin("/sys/fs/kdbus/", n->str, "/bus", NULL); if (!p) { safe_close(fd); return -ENOMEM; } *s = p; } return fd; } int bus_kernel_open_bus_fd(const char *bus, char **path) { char *p; int fd; size_t len; assert(bus); len = strlen("/sys/fs/kdbus/") + DECIMAL_STR_MAX(uid_t) + 1 + strlen(bus) + strlen("/bus") + 1; if (path) { p = new(char, len); if (!p) return -ENOMEM; } else p = newa(char, len); sprintf(p, "/sys/fs/kdbus/" UID_FMT "-%s/bus", getuid(), bus); fd = open(p, O_RDWR|O_NOCTTY|O_CLOEXEC); if (fd < 0) { if (path) free(p); return -errno; } if (path) *path = p; return fd; } int bus_kernel_try_close(sd_bus *bus) { struct kdbus_cmd byebye = { .size = sizeof(byebye) }; assert(bus); assert(bus->is_kernel); if (ioctl(bus->input_fd, KDBUS_CMD_BYEBYE, &byebye) < 0) return -errno; return 0; } int bus_kernel_drop_one(int fd) { struct kdbus_cmd_recv recv = { .size = sizeof(recv), .flags = KDBUS_RECV_DROP, }; assert(fd >= 0); if (ioctl(fd, KDBUS_CMD_RECV, &recv) < 0) return -errno; return 0; } int bus_kernel_realize_attach_flags(sd_bus *bus) { struct kdbus_cmd *update; struct kdbus_item *n; assert(bus); assert(bus->is_kernel); update = alloca0_align(offsetof(struct kdbus_cmd, items) + ALIGN8(offsetof(struct kdbus_item, data64) + sizeof(uint64_t)), 8); n = update->items; n->type = KDBUS_ITEM_ATTACH_FLAGS_RECV; n->size = offsetof(struct kdbus_item, data64) + sizeof(uint64_t); n->data64[0] = bus->attach_flags; update->size = offsetof(struct kdbus_cmd, items) + ALIGN8(n->size); if (ioctl(bus->input_fd, KDBUS_CMD_UPDATE, update) < 0) return -errno; return 0; } int bus_kernel_get_bus_name(sd_bus *bus, char **name) { struct kdbus_cmd_info cmd = { .size = sizeof(struct kdbus_cmd_info), }; struct kdbus_info *info; struct kdbus_item *item; char *n = NULL; int r; assert(bus); assert(name); assert(bus->is_kernel); r = ioctl(bus->input_fd, KDBUS_CMD_BUS_CREATOR_INFO, &cmd); if (r < 0) return -errno; info = (struct kdbus_info*) ((uint8_t*) bus->kdbus_buffer + cmd.offset); KDBUS_ITEM_FOREACH(item, info, items) if (item->type == KDBUS_ITEM_MAKE_NAME) { r = free_and_strdup(&n, item->str); break; } bus_kernel_cmd_free(bus, cmd.offset); if (r < 0) return r; if (!n) return -EIO; *name = n; return 0; }