X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Flibsystemd-bus%2Fbus-kernel.c;h=69143434b3cf9729f085a25f699552a328d678d0;hp=3d26f16cda7866f3149d973e62bf94a0b55b6cad;hb=a43b9ca3049d0f27cdb3bc8dad703e688cba31b3;hpb=8323bc1f907ff558df5ccd6bdf1e14debed5cf2e diff --git a/src/libsystemd-bus/bus-kernel.c b/src/libsystemd-bus/bus-kernel.c index 3d26f16cd..69143434b 100644 --- a/src/libsystemd-bus/bus-kernel.c +++ b/src/libsystemd-bus/bus-kernel.c @@ -19,22 +19,25 @@ along with systemd; If not, see . ***/ +#ifdef HAVE_VALGRIND_MEMCHECK_H +#include +#endif + #include +#include +#include #include "util.h" #include "bus-internal.h" #include "bus-message.h" #include "bus-kernel.h" +#include "bus-bloom.h" +#include "bus-util.h" -#define KDBUS_MSG_FOREACH_DATA(d, k) \ - for ((d) = (k)->data; \ - (uint8_t*) (d) < (uint8_t*) (k) + (k)->size; \ - (d) = (struct kdbus_msg_data*) ((uint8_t*) (d) + ALIGN8((d)->size))) - - +#define UNIQUE_NAME_MAX (3+DECIMAL_STR_MAX(uint64_t)) -static int parse_unique_name(const char *s, uint64_t *id) { +int bus_kernel_parse_unique_name(const char *s, uint64_t *id) { int r; assert(s); @@ -50,37 +53,154 @@ static int parse_unique_name(const char *s, uint64_t *id) { return 1; } -static void append_payload_vec(struct kdbus_msg_data **d, const void *p, size_t sz) { +static void append_payload_vec(struct kdbus_item **d, const void *p, size_t sz) { assert(d); - assert(p); assert(sz > 0); - (*d)->size = offsetof(struct kdbus_msg_data, vec) + sizeof(struct kdbus_vec); - (*d)->type = KDBUS_MSG_PAYLOAD_VEC; - (*d)->vec.address = (uint64_t) p; + *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_msg_data*) ((uint8_t*) *d + ALIGN8((*d)->size)); + *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_msg_data **d, const char *s, size_t length) { +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)->size = offsetof(struct kdbus_msg_data, data) + length + 1; - (*d)->type = KDBUS_MSG_DST_NAME; - memcpy((*d)->data, s, length + 1); + *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); - *d = (struct kdbus_msg_data*) ((uint8_t*) *d + ALIGN8((*d)->size)); + return r; } -static int bus_message_setup_kmsg(sd_bus_message *m) { - struct kdbus_msg_data *d; +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' + i; + else { + *(e++) = '0' + (i / 10); + *(e++) = '0' + (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); @@ -88,7 +208,7 @@ static int bus_message_setup_kmsg(sd_bus_message *m) { return 0; if (m->destination) { - r = parse_unique_name(m->destination, &unique); + r = bus_kernel_parse_unique_name(m->destination, &unique); if (r < 0) return r; @@ -96,80 +216,156 @@ static int bus_message_setup_kmsg(sd_bus_message *m) { } else well_known = false; - sz = offsetof(struct kdbus_msg, data); + 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 in fixed header, fields header, fields header padding and payload */ - sz += 4 * ALIGN8(offsetof(struct kdbus_msg_data, 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_msg, data) + dl + 1); + sz += ALIGN8(offsetof(struct kdbus_item, str) + dl + 1); } - m->kdbus = malloc0(sz); - if (!m->kdbus) - return -ENOMEM; + /* 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 & SD_BUS_MESSAGE_NO_REPLY_EXPECTED) ? 0 : KDBUS_MSG_FLAGS_EXPECT_REPLY) | ((m->header->flags & SD_BUS_MESSAGE_NO_AUTO_START) ? KDBUS_MSG_FLAGS_NO_AUTO_START : 0); m->kdbus->dst_id = well_known ? 0 : - m->destination ? unique : (uint64_t) -1; + m->destination ? unique : KDBUS_DST_ID_BROADCAST; m->kdbus->payload_type = KDBUS_PAYLOAD_DBUS1; m->kdbus->cookie = m->header->serial; m->kdbus->timeout_ns = m->timeout * NSEC_PER_USEC; - d = m->kdbus->data; + d = m->kdbus->items; if (well_known) append_destination(&d, m->destination, dl); - append_payload_vec(&d, m->header, sizeof(*m->header)); + append_payload_vec(&d, m->header, BUS_MESSAGE_BODY_BEGIN(m)); - if (m->fields) { - append_payload_vec(&d, m->fields, m->header->fields_size); + 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 (m->header->fields_size % 8 != 0) { - static const uint8_t padding[7] = {}; + 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_vec(&d, padding, 8 - (m->header->fields_size % 8)); + 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->body) - append_payload_vec(&d, m->body, m->header->body_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); - m->free_kdbus = true; - return 0; + +fail: + m->poisoned = true; + return r; } int bus_kernel_take_fd(sd_bus *b) { - struct kdbus_cmd_hello hello = {}; + struct kdbus_cmd_hello hello; int r; assert(b); + if (b->is_server) + return -EINVAL; + + 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; + 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); - r = bus_start_running(b); - if (r < 0) - return r; + /* the kernel told us the UUID of the underlying bus */ + memcpy(b->server_id.bytes, hello.id128, sizeof(b->server_id.bytes)); - return 1; + return bus_start_running(b); } int bus_kernel_connect(sd_bus *b) { @@ -178,6 +374,9 @@ int bus_kernel_connect(sd_bus *b) { 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; @@ -194,64 +393,291 @@ int bus_kernel_write_message(sd_bus *bus, sd_bus_message *m) { assert(m); assert(bus->state == BUS_RUNNING); - r = bus_message_setup_kmsg(m); + /* 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 + 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 + return 0; + } else + return -errno; + + r = bus_message_new_synthetic_error( + bus, + BUS_MESSAGE_SERIAL(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_MSG_RELEASE, &off); + + KDBUS_PART_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 errno == EAGAIN ? 0 : -errno; + return r; - return 0; + 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 void close_kdbus_msg(struct kdbus_msg *k) { - struct kdbus_msg_data *d; +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); - KDBUS_MSG_FOREACH_DATA(d, k) { + if (d->name_change.flags != 0) + return 0; - if (d->type != KDBUS_MSG_UNIX_FDS) - continue; + if (d->type == KDBUS_ITEM_NAME_ADD) + 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) + 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; - close_many(d->fds, (d->size - offsetof(struct kdbus_msg_data, fds)) / sizeof(int)); + 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_PART_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 **ret) { +int kdbus_translate_attach_flags(uint64_t mask, uint64_t *kdbus_mask) { + + uint64_t m = 0; + + SET_FLAG(m, KDBUS_ATTACH_CREDS, + !!(mask & (SD_BUS_CREDS_UID|SD_BUS_CREDS_GID|SD_BUS_CREDS_PID|SD_BUS_CREDS_PID_STARTTIME|SD_BUS_CREDS_TID))); + + SET_FLAG(m, KDBUS_ATTACH_COMM, + !!(mask & (SD_BUS_CREDS_COMM|SD_BUS_CREDS_TID_COMM))); + + SET_FLAG(m, KDBUS_ATTACH_EXE, + !!(mask & SD_BUS_CREDS_EXE)); + + SET_FLAG(m, KDBUS_ATTACH_CMDLINE, + !!(mask & SD_BUS_CREDS_CMDLINE)); + + SET_FLAG(m, KDBUS_ATTACH_CGROUP, + !!(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))); + + SET_FLAG(m, KDBUS_ATTACH_CAPS, + !!(mask & (SD_BUS_CREDS_EFFECTIVE_CAPS|SD_BUS_CREDS_PERMITTED_CAPS|SD_BUS_CREDS_INHERITABLE_CAPS|SD_BUS_CREDS_BOUNDING_CAPS))); + + SET_FLAG(m, KDBUS_ATTACH_SECLABEL, + !!(mask & SD_BUS_CREDS_SELINUX_CONTEXT)); + + SET_FLAG(m, KDBUS_ATTACH_AUDIT, + !!(mask & (SD_BUS_CREDS_AUDIT_SESSION_ID|SD_BUS_CREDS_AUDIT_LOGIN_UID))); + + *kdbus_mask = m; + + return 0; +} + +static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { sd_bus_message *m = NULL; - struct kdbus_msg_data *d; - unsigned n_payload = 0, n_fds = 0; + 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; - struct kdbus_creds *creds = NULL; + const char *destination = NULL, *seclabel = NULL; int r; assert(bus); assert(k); - assert(ret); + assert(k->payload_type == KDBUS_PAYLOAD_DBUS1); - if (k->payload_type != KDBUS_PAYLOAD_DBUS1) - return 0; - - KDBUS_MSG_FOREACH_DATA(d, k) { + KDBUS_PART_FOREACH(d, k, items) { size_t l; - l = d->size - offsetof(struct kdbus_msg_data, data); + l = d->size - offsetof(struct kdbus_item, data); - if (d->type == KDBUS_MSG_PAYLOAD) { + switch (d->type) { + case KDBUS_ITEM_PAYLOAD_OFF: if (!h) { - if (l < sizeof(struct bus_header)) - return -EBADMSG; + h = (struct bus_header *)((uint8_t *)bus->kdbus_buffer + d->vec.offset); - h = (struct bus_header*) d->data; + if (!bus_header_is_complete(h, d->vec.size)) + return -EBADMSG; } - n_payload++; - n_bytes += l; + n_bytes += d->vec.size; + break; + + case KDBUS_ITEM_PAYLOAD_MEMFD: + if (!h) + return -EBADMSG; - } else if (d->type == KDBUS_MSG_UNIX_FDS) { + n_bytes += d->memfd.size; + break; + + case KDBUS_ITEM_FDS: { int *f; unsigned j; @@ -261,117 +687,245 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_mess return -ENOMEM; fds = f; - memcpy(fds + n_fds, d->fds, j); + memcpy(fds + n_fds, d->fds, sizeof(int) * j); n_fds += j; + break; + } - } else if (d->type == KDBUS_MSG_SRC_CREDS) - creds = &d->creds; + case KDBUS_ITEM_SECLABEL: + seclabel = d->str; + break; + } } if (!h) return -EBADMSG; - r = bus_header_size(h, &total); + r = bus_header_message_size(h, &total); if (r < 0) return r; if (n_bytes != total) return -EBADMSG; - r = bus_message_from_header(h, sizeof(struct bus_header), fds, n_fds, NULL, NULL, 0, &m); + r = bus_message_from_header(bus, h, sizeof(struct bus_header), fds, n_fds, NULL, seclabel, 0, &m); if (r < 0) return r; - KDBUS_MSG_FOREACH_DATA(d, k) { + KDBUS_PART_FOREACH(d, k, items) { size_t l; - if (d->type != KDBUS_MSG_PAYLOAD) - continue; + 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; - l = d->size - offsetof(struct kdbus_msg_data, data); - if (idx == sizeof(struct bus_header) && - l == BUS_MESSAGE_FIELDS_SIZE(m)) - m->fields = d->data; - else if (idx == sizeof(struct bus_header) + ALIGN8(BUS_MESSAGE_FIELDS_SIZE(m)) && - l == BUS_MESSAGE_BODY_SIZE(m)) - m->body = d->data; - else if (!(idx == 0 && l == sizeof(struct bus_header)) && - !(idx == sizeof(struct bus_header) + BUS_MESSAGE_FIELDS_SIZE(m))) { - sd_bus_message_unref(m); - return -EBADMSG; + /* 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 *)bus->kdbus_buffer + 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->size = d->vec.size - (begin_body - idx); + } + + part->sealed = true; + } + + idx += d->vec.size; + break; } - idx += l; - } + 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: + m->creds.pid_starttime = d->creds.starttime / NSEC_PER_USEC; + m->creds.uid = d->creds.uid; + m->creds.gid = d->creds.gid; + m->creds.pid = d->creds.pid; + m->creds.tid = d->creds.tid; + m->creds.mask |= (SD_BUS_CREDS_UID|SD_BUS_CREDS_GID|SD_BUS_CREDS_PID|SD_BUS_CREDS_PID_STARTTIME|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_length = 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; + break; + + case KDBUS_ITEM_AUDIT: + m->creds.audit_session_id = d->audit.sessionid; + m->creds.audit_login_uid = 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: + destination = d->str; + break; - if (creds) { - m->pid_starttime = creds->starttime / NSEC_PER_USEC; - m->uid = creds->uid; - m->gid = creds->gid; - m->pid = creds->pid; - m->tid = creds->tid; - m->uid_valid = m->gid_valid = true; + case KDBUS_ITEM_FDS: + case KDBUS_ITEM_SECLABEL: + case KDBUS_ITEM_NAMES: + break; + + default: + log_debug("Got unknown field from kernel %llu", d->type); + } } r = bus_message_parse_fields(m); - if (r < 0) { - sd_bus_message_unref(m); - return r; + if (r < 0) + goto fail; + + if (k->src_id == KDBUS_SRC_ID_KERNEL) + m->sender = "org.freedesktop.DBus"; + else { + snprintf(m->sender_buffer, sizeof(m->sender_buffer), ":1.%llu", (unsigned long long) k->src_id); + m->sender = m->sender_buffer; + } + + if (!m->destination) { + if (destination) + m->destination = destination; + else if (k->dst_id != KDBUS_DST_ID_WELL_KNOWN_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; + } } /* We take possession of the kmsg struct now */ m->kdbus = k; - m->free_kdbus = true; + m->release_kdbus = true; m->free_fds = true; - fds = NULL; - *ret = m; + 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, sd_bus_message **m) { +int bus_kernel_read_message(sd_bus *bus) { struct kdbus_msg *k; - size_t sz = 128; + uint64_t off; int r; assert(bus); - assert(m); - for (;;) { - void *q; - - q = realloc(bus->rbuffer, sz); - if (!q) - return -errno; - - k = bus->rbuffer = q; - k->size = sz; - - r = ioctl(bus->input_fd, KDBUS_CMD_MSG_RECV, bus->rbuffer); - if (r >= 0) - break; + 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; - if (errno != ENOBUFS) - return -errno; - - sz *= 2; + return -errno; } + k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + off); - r = bus_kernel_make_message(bus, k, m); - if (r > 0) - bus->rbuffer = NULL; + if (k->payload_type == KDBUS_PAYLOAD_DBUS1) + r = bus_kernel_make_message(bus, k); + else if (k->payload_type == KDBUS_PAYLOAD_KERNEL) + r = bus_kernel_translate_message(bus, k); else - close_kdbus_msg(k); + r = 0; - return r; + if (r <= 0) + close_kdbus_msg(bus, k); + + return r < 0 ? r : 1; } int bus_kernel_create(const char *name, char **s) { - struct kdbus_cmd_fname *fname; + struct kdbus_cmd_bus_make *make; + struct kdbus_item *n; size_t l; int fd; char *p; @@ -384,17 +938,26 @@ int bus_kernel_create(const char *name, char **s) { return -errno; l = strlen(name); - fname = alloca(offsetof(struct kdbus_cmd_fname, name) + DECIMAL_STR_MAX(uid_t) + 1 + l + 1); - sprintf(fname->name, "%lu-%s", (unsigned long) getuid(), name); - fname->size = offsetof(struct kdbus_cmd_fname, name) + strlen(fname->name) + 1; - fname->kernel_flags = KDBUS_CMD_FNAME_ACCESS_WORLD; - fname->user_flags = 0; - - p = strjoin("/dev/kdbus/", fname->name, "/bus", NULL); + make = alloca0(offsetof(struct kdbus_cmd_bus_make, items) + + KDBUS_PART_HEADER_SIZE + sizeof(uint64_t) + + KDBUS_PART_HEADER_SIZE + DECIMAL_STR_MAX(uid_t) + 1 + l + 1); + + n = make->items; + n->type = KDBUS_MAKE_NAME; + sprintf(n->str, "%lu-%s", (unsigned long) getuid(), name); + n->size = KDBUS_PART_HEADER_SIZE + strlen(n->str) + 1; + + make->size = 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); + + p = strjoin("/dev/kdbus/", n->str, "/bus", NULL); if (!p) return -ENOMEM; - if (ioctl(fd, KDBUS_CMD_BUS_MAKE, fname) < 0) { + if (ioctl(fd, KDBUS_CMD_BUS_MAKE, make) < 0) { close_nointr_nofail(fd); free(p); return -errno; @@ -405,3 +968,113 @@ int bus_kernel_create(const char *name, char **s) { return fd; } + +int bus_kernel_pop_memfd(sd_bus *bus, void **address, size_t *size) { + struct memfd_cache *c; + int fd; + + assert(address); + assert(size); + + 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; + *size = 0; + return fd; + } + + c = &bus->memfd_cache[--bus->n_memfd_cache]; + + assert(c->fd >= 0); + assert(c->size == 0 || c->address); + + *address = c->address; + *size = c->size; + 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 size) { + struct memfd_cache *c; + uint64_t max_sz = PAGE_ALIGN(MEMFD_CACHE_ITEM_SIZE_MAX); + + assert(fd >= 0); + assert(size == 0 || address); + + if (!bus || !bus->is_kernel) { + close_and_munmap(fd, address, size); + 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, size); + 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 (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; + + 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].size); +} + +int kdbus_translate_request_name_flags(uint64_t sd_bus_flags, uint64_t *kdbus_flags) { + + assert_return(kdbus_flags != NULL, -EINVAL); + + *kdbus_flags = 0; + + if (sd_bus_flags & SD_BUS_NAME_ALLOW_REPLACEMENT) + *kdbus_flags |= KDBUS_NAME_ALLOW_REPLACEMENT; + + if (sd_bus_flags & SD_BUS_NAME_REPLACE_EXISTING) + *kdbus_flags |= KDBUS_NAME_REPLACE_EXISTING; + + if (!(sd_bus_flags & SD_BUS_NAME_DO_NOT_QUEUE)) + *kdbus_flags |= KDBUS_NAME_QUEUE; + + return 0; +}