X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Flibsystemd-bus%2Fbus-kernel.c;h=05544e1e477403716292383feef0cdcaaa2ab2e1;hp=2c87f22fd7f5e7509d9d27f52055f4e946746e61;hb=96415cad2fdd8d280ae94b02651b5f826a2f7f3d;hpb=65dae17a2f890b12a07dd4901b3db02b1031c463 diff --git a/src/libsystemd-bus/bus-kernel.c b/src/libsystemd-bus/bus-kernel.c index 2c87f22fd..05544e1e4 100644 --- a/src/libsystemd-bus/bus-kernel.c +++ b/src/libsystemd-bus/bus-kernel.c @@ -254,7 +254,7 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) { m->kdbus->dst_id = well_known ? 0 : m->destination ? unique : KDBUS_DST_ID_BROADCAST; - m->kdbus->payload_type = KDBUS_PAYLOAD_DBUS1; + m->kdbus->payload_type = KDBUS_PAYLOAD_DBUS; m->kdbus->cookie = m->header->serial; m->kdbus->timeout_ns = m->timeout * NSEC_PER_USEC; @@ -317,7 +317,9 @@ fail: } int bus_kernel_take_fd(sd_bus *b) { - struct kdbus_cmd_hello hello; + struct kdbus_cmd_hello *hello; + struct kdbus_item *item; + size_t l = 0, sz; int r; assert(b); @@ -327,13 +329,38 @@ int bus_kernel_take_fd(sd_bus *b) { b->use_memfd = 1; - zero(hello); - hello.size = sizeof(hello); - hello.conn_flags = b->hello_flags; - hello.attach_flags = b->attach_flags; - hello.pool_size = KDBUS_POOL_SIZE; + 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); + } - r = ioctl(b->input_fd, KDBUS_CMD_HELLO, &hello); + 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; @@ -347,24 +374,26 @@ int bus_kernel_take_fd(sd_bus *b) { /* 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) + if (hello->bus_flags > 0xFFFFFFFFULL || + hello->conn_flags > 0xFFFFFFFFULL) return -ENOTSUP; - if (hello.bloom_size != BLOOM_SIZE) + if (hello->bloom_size != BLOOM_SIZE) return -ENOTSUP; - if (asprintf(&b->unique_name, ":1.%llu", (unsigned long long) hello.id) < 0) + if (asprintf(&b->unique_name, ":1.%llu", (unsigned long long) hello->id) < 0) return -ENOMEM; - b->unique_id = hello.id; + b->unique_id = hello->id; b->is_kernel = true; b->bus_client = true; - b->can_fds = !!(hello.conn_flags & KDBUS_HELLO_ACCEPT_FD); + 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)); + memcpy(b->server_id.bytes, hello->id128, sizeof(b->server_id.bytes)); return bus_start_running(b); } @@ -417,8 +446,10 @@ int bus_kernel_write_message(sd_bus *bus, sd_bus_message *m) { 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 + else { + log_debug("Could not deliver message to %s as destination is not known. Ignoring.", m->destination); return 0; + } } else if (errno == EADDRNOTAVAIL) { @@ -426,8 +457,10 @@ int bus_kernel_write_message(sd_bus *bus, sd_bus_message *m) { 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 + else { + log_debug("Could not deliver message to %s as destination is not activated. Ignoring.", m->destination); return 0; + } } else return -errno; @@ -462,7 +495,7 @@ static void close_kdbus_msg(sd_bus *bus, struct kdbus_msg *k) { off = (uint8_t *)k - (uint8_t *)bus->kdbus_buffer; ioctl(bus->input_fd, KDBUS_CMD_FREE, &off); - KDBUS_PART_FOREACH(d, k, items) { + 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)); @@ -509,18 +542,19 @@ static int translate_name_change(sd_bus *bus, struct kdbus_msg *k, struct kdbus_ assert(k); assert(d); - if (d->name_change.flags != 0) - return 0; - - if (d->type == KDBUS_ITEM_NAME_ADD) + 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); + 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; - if (d->type == KDBUS_ITEM_NAME_REMOVE) new_owner[0] = 0; - else - sprintf(new_owner, ":1.%llu", (unsigned long long) d->name_change.new_id); + } 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); } @@ -589,7 +623,7 @@ static int bus_kernel_translate_message(sd_bus *bus, struct kdbus_msg *k) { assert(k); assert(k->payload_type == KDBUS_PAYLOAD_KERNEL); - KDBUS_PART_FOREACH(d, k, items) { + 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; @@ -618,9 +652,9 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { assert(bus); assert(k); - assert(k->payload_type == KDBUS_PAYLOAD_DBUS1); + assert(k->payload_type == KDBUS_PAYLOAD_DBUS); - KDBUS_PART_FOREACH(d, k, items) { + KDBUS_ITEM_FOREACH(d, k, items) { size_t l; l = d->size - offsetof(struct kdbus_item, data); @@ -629,7 +663,7 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { case KDBUS_ITEM_PAYLOAD_OFF: if (!h) { - h = (struct bus_header *)((uint8_t *)bus->kdbus_buffer + d->vec.offset); + h = (struct bus_header *)((uint8_t *)k + d->vec.offset); if (!bus_header_is_complete(h, d->vec.size)) return -EBADMSG; @@ -676,11 +710,24 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { 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; - KDBUS_PART_FOREACH(d, k, items) { + /* 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); @@ -708,11 +755,11 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { if (idx >= begin_body) { if (!part->is_zero) - part->data = (uint8_t *)bus->kdbus_buffer + d->vec.offset; + part->data = (uint8_t *)k + d->vec.offset; part->size = d->vec.size; } else { if (!part->is_zero) - part->data = (uint8_t *)bus->kdbus_buffer + d->vec.offset + (begin_body - idx); + part->data = (uint8_t *)k + d->vec.offset + (begin_body - idx); part->size = d->vec.size - (begin_body - idx); } @@ -805,7 +852,6 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { r = strv_extend(&m->creds.well_known_names, d->name.name); if (r < 0) goto fail; - m->creds.mask |= SD_BUS_CREDS_WELL_KNOWN_NAMES & bus->creds_mask; break; case KDBUS_ITEM_FDS: @@ -821,22 +867,23 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { 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 = "org.freedesktop.DBus"; + 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; - m->creds.mask |= SD_BUS_CREDS_UNIQUE_NAME & bus->creds_mask; } - if (!m->destination) { - if (destination) - m->destination = destination; - else if (k->dst_id != KDBUS_DST_ID_NAME && - k->dst_id != KDBUS_DST_ID_BROADCAST) { - snprintf(m->destination_buffer, sizeof(m->destination_buffer), ":1.%llu", (unsigned long long) k->dst_id); - m->destination = m->destination_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 */ @@ -885,9 +932,16 @@ int bus_kernel_read_message(sd_bus *bus) { } k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + off); - if (k->payload_type == KDBUS_PAYLOAD_DBUS1) + if (k->payload_type == KDBUS_PAYLOAD_DBUS) { r = bus_kernel_make_message(bus, k); - else if (k->payload_type == KDBUS_PAYLOAD_KERNEL) + + /* 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; @@ -898,12 +952,13 @@ int bus_kernel_read_message(sd_bus *bus) { return r < 0 ? r : 1; } -int bus_kernel_pop_memfd(sd_bus *bus, void **address, size_t *size) { +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(size); + assert(mapped); + assert(allocated); if (!bus || !bus->is_kernel) return -ENOTSUP; @@ -920,17 +975,19 @@ int bus_kernel_pop_memfd(sd_bus *bus, void **address, size_t *size) { return -errno; *address = NULL; - *size = 0; + *mapped = 0; + *allocated = 0; return fd; } c = &bus->memfd_cache[--bus->n_memfd_cache]; assert(c->fd >= 0); - assert(c->size == 0 || c->address); + assert(c->mapped == 0 || c->address); *address = c->address; - *size = c->size; + *mapped = c->mapped; + *allocated = c->allocated; fd = c->fd; assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0); @@ -945,15 +1002,15 @@ static void close_and_munmap(int fd, void *address, size_t size) { close_nointr_nofail(fd); } -void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t size) { +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_sz = PAGE_ALIGN(MEMFD_CACHE_ITEM_SIZE_MAX); + uint64_t max_mapped = PAGE_ALIGN(MEMFD_CACHE_ITEM_SIZE_MAX); assert(fd >= 0); - assert(size == 0 || address); + assert(mapped == 0 || address); if (!bus || !bus->is_kernel) { - close_and_munmap(fd, address, size); + close_and_munmap(fd, address, mapped); return; } @@ -962,7 +1019,7 @@ void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t size) { if (bus->n_memfd_cache >= ELEMENTSOF(bus->memfd_cache)) { assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0); - close_and_munmap(fd, address, size); + close_and_munmap(fd, address, mapped); return; } @@ -971,12 +1028,14 @@ void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t size) { c->address = address; /* If overly long, let's return a bit to the OS */ - if (size > max_sz) { - assert_se(ioctl(fd, KDBUS_CMD_MEMFD_SIZE_SET, &max_sz) >= 0); - assert_se(munmap((uint8_t*) address + max_sz, PAGE_ALIGN(size - max_sz)) >= 0); - c->size = max_sz; - } else - c->size = size; + 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); } @@ -987,7 +1046,7 @@ void bus_kernel_flush_memfd(sd_bus *b) { 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].size); + 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) { @@ -1001,7 +1060,7 @@ int kdbus_translate_request_name_flags(uint64_t flags, uint64_t *kdbus_flags) { if (flags & SD_BUS_NAME_REPLACE_EXISTING) f |= KDBUS_NAME_REPLACE_EXISTING; - if (!(flags & SD_BUS_NAME_DO_NOT_QUEUE)) + if (flags & SD_BUS_NAME_QUEUE) f |= KDBUS_NAME_QUEUE; *kdbus_flags = f; @@ -1045,7 +1104,7 @@ int kdbus_translate_attach_flags(uint64_t mask, uint64_t *kdbus_mask) { } int bus_kernel_create_bus(const char *name, char **s) { - struct kdbus_cmd_bus_make *make; + struct kdbus_cmd_make *make; struct kdbus_item *n; int fd; @@ -1056,20 +1115,27 @@ int bus_kernel_create_bus(const char *name, char **s) { if (fd < 0) return -errno; - make = alloca0(ALIGN8(offsetof(struct kdbus_cmd_bus_make, items) + + 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_MAKE_NAME; + n->type = KDBUS_ITEM_MAKE_NAME; + make->size += ALIGN8(n->size); - make->size = ALIGN8(offsetof(struct kdbus_cmd_bus_make, items) + n->size); make->flags = KDBUS_MAKE_POLICY_OPEN; - make->bus_flags = 0; - make->bloom_size = BLOOM_SIZE; - assert_cc(BLOOM_SIZE % 8 == 0); if (ioctl(fd, KDBUS_CMD_BUS_MAKE, make) < 0) { close_nointr_nofail(fd); @@ -1121,10 +1187,10 @@ int bus_kernel_create_starter(const char *bus, const char *name) { n = hello->items; strcpy(n->str, name); n->size = offsetof(struct kdbus_item, str) + strlen(n->str) + 1; - n->type = KDBUS_ITEM_STARTER_NAME; + n->type = KDBUS_ITEM_NAME; hello->size = ALIGN8(offsetof(struct kdbus_cmd_hello, items) + n->size); - hello->conn_flags = KDBUS_HELLO_STARTER; + hello->conn_flags = KDBUS_HELLO_ACTIVATOR; hello->pool_size = KDBUS_POOL_SIZE; if (ioctl(fd, KDBUS_CMD_HELLO, hello) < 0) { @@ -1149,7 +1215,7 @@ int bus_kernel_create_starter(const char *bus, const char *name) { } int bus_kernel_create_namespace(const char *name, char **s) { - struct kdbus_cmd_ns_make *make; + struct kdbus_cmd_make *make; struct kdbus_item *n; int fd; @@ -1160,16 +1226,16 @@ int bus_kernel_create_namespace(const char *name, char **s) { if (fd < 0) return -errno; - make = alloca0(ALIGN8(offsetof(struct kdbus_cmd_ns_make, items) + + 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_MAKE_NAME; + n->type = KDBUS_ITEM_MAKE_NAME; - make->size = ALIGN8(offsetof(struct kdbus_cmd_ns_make, items) + n->size); + 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) { @@ -1198,3 +1264,48 @@ int bus_kernel_create_namespace(const char *name, char **s) { 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; +}