X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Flibsystemd%2Fsd-bus%2Fbus-kernel.c;h=a7d18e337b874244b97cccfc9348ffa10c68f74d;hp=712ef00fcb8c69d899923cb6b13954bd4368855e;hb=412c18f10c9df3f0a02358d8c0e707ed2e5fa186;hpb=486e99a387adec15738c2822c2df5c813955f433 diff --git a/src/libsystemd/sd-bus/bus-kernel.c b/src/libsystemd/sd-bus/bus-kernel.c index 712ef00fc..a7d18e337 100644 --- a/src/libsystemd/sd-bus/bus-kernel.c +++ b/src/libsystemd/sd-bus/bus-kernel.c @@ -25,18 +25,22 @@ #include #include +#include #include #include #include "util.h" #include "strv.h" +#include "memfd-util.h" +#include "cgroup-util.h" +#include "fileio.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" +#include "bus-label.h" #define UNIQUE_NAME_MAX (3+DECIMAL_STR_MAX(uint64_t)) @@ -201,6 +205,7 @@ static int bus_message_setup_bloom(sd_bus_message *m, struct kdbus_bloom_filter 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; uint64_t unique; size_t sz, dl; @@ -216,8 +221,10 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) { if (m->kdbus) return 0; - if (m->destination) { - r = bus_kernel_parse_unique_name(m->destination, &unique); + destination = m->destination ?: m->destination_ptr; + + if (destination) { + r = bus_kernel_parse_unique_name(destination, &unique); if (r < 0) return r; @@ -241,7 +248,7 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) { /* Add in well-known destination header */ if (well_known) { - dl = strlen(m->destination); + dl = strlen(destination); sz += ALIGN8(offsetof(struct kdbus_item, str) + dl + 1); } @@ -261,22 +268,34 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) { 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; + + if (well_known) + /* 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 weel-known-name, and fail if they + * differ. Currently, this is only needed for bus-proxyd. */ + m->kdbus->dst_id = m->verify_destination_id; + else + m->kdbus->dst_id = destination ? unique : KDBUS_DST_ID_BROADCAST; + m->kdbus->payload_type = KDBUS_PAYLOAD_DBUS; - m->kdbus->cookie = m->header->serial; + m->kdbus->cookie = (uint64_t) m->header->serial; m->kdbus->priority = m->priority; 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; + 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, m->destination, dl); + append_destination(&d, destination, dl); append_payload_vec(&d, m->header, BUS_MESSAGE_BODY_BEGIN(m)); @@ -291,7 +310,7 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) { continue; } - if (part->memfd >= 0 && part->sealed && m->destination) { + 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 */ @@ -299,8 +318,8 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) { continue; } - /* Otherwise let's send a vector to the actual data, - * for that we need to map it first. */ + /* 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; @@ -330,6 +349,27 @@ fail: return r; } +static void bus_message_set_sender_driver(sd_bus *bus, sd_bus_message *m) { + assert(bus); + assert(m); + + m->sender = m->creds.unique_name = (char*) "org.freedesktop.DBus"; + m->creds.well_known_names_driver = true; + m->creds.mask |= (SD_BUS_CREDS_UNIQUE_NAME|SD_BUS_CREDS_WELL_KNOWN_NAMES) & bus->creds_mask; +} + +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 int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { sd_bus_message *m = NULL; struct kdbus_item *d; @@ -482,28 +522,75 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { 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; + case KDBUS_ITEM_PIDS: + + /* The PID starttime/TID might be missing, + * 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->pids.pid > 0) { + m->creds.pid = (pid_t) d->pids.pid; + m->creds.mask |= SD_BUS_CREDS_PID & bus->creds_mask; + } + + if (d->pids.starttime > 0) { + m->creds.pid_starttime = d->pids.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; + if (d->pids.tid > 0) { + m->creds.tid = (pid_t) d->pids.tid; m->creds.mask |= SD_BUS_CREDS_TID & 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_t) -1) { + 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_t) -1) { + 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_t) -1) { + 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_t) -1) { + 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_t) -1) { + 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_t) -1) { + 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_t) -1) { + 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_t) -1) { + m->creds.fsgid = (gid_t) d->creds.fsgid; + m->creds.mask |= SD_BUS_CREDS_FSGID & bus->creds_mask; + } + break; case KDBUS_ITEM_TIMESTAMP: @@ -541,47 +628,85 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { 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; - } + 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.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; + if ((uint32_t) d->audit.sessionid != (uint32_t) -1) { + m->creds.audit_session_id = (uint32_t) d->audit.sessionid; + m->creds.mask |= SD_BUS_CREDS_AUDIT_SESSION_ID & bus->creds_mask; + } + + if ((uid_t) d->audit.loginuid != (uid_t) -1) { + 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: - m->creds.capability = d->data; - m->creds.capability_size = l; + m->creds.capability = (uint8_t *) d->caps.caps; + m->creds.capability_size = d->size - offsetof(struct kdbus_item, 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)) - return -EBADMSG; + if (!service_name_is_valid(d->str)) { + r = -EBADMSG; + goto fail; + } 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) + 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_NAME: - m->creds.conn_name = d->str; - m->creds.mask |= SD_BUS_CREDS_CONNECTION_NAME & bus->creds_mask; + 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) { + assert_cc(sizeof(gid_t) == sizeof(uint32_t)); + + m->creds.n_supplementary_gids = (d->size - offsetof(struct kdbus_item, data32)) / sizeof(uint32_t); + m->creds.supplementary_gids = (gid_t*) d->data32; + m->creds.mask |= SD_BUS_CREDS_SUPPLEMENTARY_GIDS; + } + break; case KDBUS_ITEM_FDS: @@ -593,13 +718,45 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { } } + /* 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 we 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->serial != 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_FLAGS_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_FLAGS_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) - m->sender = m->creds.unique_name = (char*) "org.freedesktop.DBus"; + bus_message_set_sender_driver(bus, m); 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; @@ -627,17 +784,8 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { 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); - } + unset_memfds(m); + sd_bus_message_unref(m); return r; } @@ -657,8 +805,8 @@ int bus_kernel_take_fd(sd_bus *b) { b->use_memfd = 1; - if (b->connection_name) { - g = sd_bus_label_escape(b->connection_name); + if (b->description) { + g = bus_label_escape(b->description); if (!g) return -ENOMEM; @@ -678,7 +826,7 @@ int bus_kernel_take_fd(sd_bus *b) { } else { _cleanup_free_ char *e = NULL; - e = sd_bus_label_escape(pr); + e = bus_label_escape(pr); if (!e) return -ENOMEM; @@ -691,8 +839,8 @@ int bus_kernel_take_fd(sd_bus *b) { name = g; } - b->connection_name = sd_bus_label_unescape(name); - if (!b->connection_name) + b->description = bus_label_unescape(name); + if (!b->description) return -ENOMEM; } @@ -704,21 +852,25 @@ int bus_kernel_take_fd(sd_bus *b) { 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(sz); + hello = alloca0_align(sz, 8); hello->size = sz; - hello->conn_flags = b->hello_flags; - hello->attach_flags = b->attach_flags; + 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_NAME; + item->type = KDBUS_ITEM_CONN_DESCRIPTION; memcpy(item->str, name, m + 1); item = KDBUS_ITEM_NEXT(item); @@ -730,6 +882,14 @@ int bus_kernel_take_fd(sd_bus *b) { 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; @@ -748,10 +908,9 @@ int bus_kernel_take_fd(sd_bus *b) { } } - /* The higher 32bit of both flags fields are considered + /* The higher 32bit of the bus_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) return -ENOTSUP; if (!bloom_validate_parameters((size_t) hello->bloom.size, (unsigned) hello->bloom.n_hash)) @@ -767,7 +926,7 @@ int bus_kernel_take_fd(sd_bus *b) { b->is_kernel = true; b->bus_client = true; - b->can_fds = !!(hello->conn_flags & KDBUS_HELLO_ACCEPT_FD); + b->can_fds = !!(hello->flags & KDBUS_HELLO_ACCEPT_FD); b->message_version = 2; b->message_endian = BUS_NATIVE_ENDIAN; @@ -796,22 +955,23 @@ int bus_kernel_connect(sd_bus *b) { } static void close_kdbus_msg(sd_bus *bus, struct kdbus_msg *k) { - uint64_t off; + struct kdbus_cmd_free cmd = {}; 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); + cmd.offset = (uint8_t *)k - (uint8_t *)bus->kdbus_buffer; 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); + safe_close(d->memfd.fd); } + + (void) ioctl(bus->input_fd, KDBUS_CMD_FREE, &cmd); } int bus_kernel_write_message(sd_bus *bus, sd_bus_message *m, bool hint_sync_call) { @@ -920,10 +1080,10 @@ static int push_name_owner_changed(sd_bus *bus, const char *name, const char *ol r = sd_bus_message_new_signal( bus, + &m, "/org/freedesktop/DBus", "org.freedesktop.DBus", - "NameOwnerChanged", - &m); + "NameOwnerChanged"); if (r < 0) return r; @@ -931,7 +1091,7 @@ static int push_name_owner_changed(sd_bus *bus, const char *name, const char *ol if (r < 0) return r; - m->sender = "org.freedesktop.DBus"; + bus_message_set_sender_driver(bus, m); r = bus_seal_synthetic_message(bus, m); if (r < 0) @@ -950,19 +1110,19 @@ static int translate_name_change(sd_bus *bus, struct kdbus_msg *k, struct kdbus_ assert(k); assert(d); - if (d->type == KDBUS_ITEM_NAME_ADD || (d->name_change.old.flags & (KDBUS_NAME_IN_QUEUE|KDBUS_NAME_ACTIVATOR))) + 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); + 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.flags & (KDBUS_NAME_IN_QUEUE|KDBUS_NAME_ACTIVATOR))) { + 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); + 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); } @@ -1000,7 +1160,7 @@ static int translate_reply(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item * if (r < 0) return r; - m->sender = "org.freedesktop.DBus"; + bus_message_set_sender_driver(bus, m); r = bus_seal_synthetic_message(bus, m); if (r < 0) @@ -1069,6 +1229,11 @@ int bus_kernel_read_message(sd_bus *bus, bool hint_priority, int64_t priority) { if (errno == EAGAIN) return 0; + if (errno == EOVERFLOW) { + log_debug("%s: kdbus reports %" PRIu64 " dropped broadcast messages, ignoring.", strna(bus->description), (uint64_t) recv.dropped_msgs); + return 0; + } + return -errno; } @@ -1109,40 +1274,18 @@ int bus_kernel_pop_memfd(sd_bus *bus, void **address, size_t *mapped, size_t *al assert_se(pthread_mutex_lock(&bus->memfd_cache_mutex) >= 0); if (bus->n_memfd_cache <= 0) { - _cleanup_free_ char *g = NULL; - struct kdbus_cmd_memfd_make *cmd; - struct kdbus_item *item; - size_t l, sz; int r; assert_se(pthread_mutex_unlock(&bus->memfd_cache_mutex) >= 0); - assert(bus->connection_name); - - g = sd_bus_label_escape(bus->connection_name); - if (!g) - return -ENOMEM; - - l = strlen(g); - sz = ALIGN8(offsetof(struct kdbus_cmd_memfd_make, items)) + - ALIGN8(offsetof(struct kdbus_item, str)) + - l + 1; - cmd = alloca0(sz); - cmd->size = sz; - - item = cmd->items; - item->size = ALIGN8(offsetof(struct kdbus_item, str)) + l + 1; - item->type = KDBUS_ITEM_MEMFD_NAME; - memcpy(item->str, g, l + 1); - - r = ioctl(bus->input_fd, KDBUS_CMD_MEMFD_NEW, cmd); + r = memfd_new(bus->description); if (r < 0) - return -errno; + return r; *address = NULL; *mapped = 0; *allocated = 0; - return cmd->fd; + return r; } c = &bus->memfd_cache[--bus->n_memfd_cache]; @@ -1164,7 +1307,7 @@ 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); + safe_close(fd); } void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t mapped, size_t allocated) { @@ -1194,7 +1337,7 @@ void bus_kernel_push_memfd(sd_bus *bus, int fd, void *address, size_t mapped, si /* 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(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 { @@ -1214,11 +1357,9 @@ void bus_kernel_flush_memfd(sd_bus *b) { 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 request_name_flags_to_kdbus(uint64_t flags) { uint64_t f = 0; - assert(kdbus_flags); - if (flags & SD_BUS_NAME_ALLOW_REPLACEMENT) f |= KDBUS_NAME_ALLOW_REPLACEMENT; @@ -1228,20 +1369,24 @@ int kdbus_translate_request_name_flags(uint64_t flags, uint64_t *kdbus_flags) { if (flags & SD_BUS_NAME_QUEUE) f |= KDBUS_NAME_QUEUE; - *kdbus_flags = f; - return 0; + return f; } -int kdbus_translate_attach_flags(uint64_t mask, uint64_t *kdbus_mask) { +uint64_t attach_flags_to_kdbus(uint64_t 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)) + 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_COMM|SD_BUS_CREDS_TID_COMM)) - m |= KDBUS_ATTACH_COMM; + if (mask & (SD_BUS_CREDS_PID|SD_BUS_CREDS_PID_STARTTIME|SD_BUS_CREDS_TID)) + 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; @@ -1264,37 +1409,42 @@ int kdbus_translate_attach_flags(uint64_t mask, uint64_t *kdbus_mask) { if (mask & SD_BUS_CREDS_WELL_KNOWN_NAMES) m |= KDBUS_ATTACH_NAMES; - if (mask & SD_BUS_CREDS_CONNECTION_NAME) - m |= KDBUS_ATTACH_CONN_NAME; + if (mask & SD_BUS_CREDS_DESCRIPTION) + m |= KDBUS_ATTACH_CONN_DESCRIPTION; - *kdbus_mask = m; - return 0; + 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 *make; struct kdbus_item *n; + size_t l; int fd; assert(name); assert(s); - fd = open("/dev/kdbus/control", O_RDWR|O_NOCTTY|O_CLOEXEC); + fd = open("/sys/fs/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)); + l = strlen(name); + make = alloca0_align(offsetof(struct kdbus_cmd_make, 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_make, 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; @@ -1303,32 +1453,34 @@ int bus_kernel_create_bus(const char *name, bool world, char **s) { make->size += ALIGN8(n->size); + /* The busses we create make no restrictions on what metadata + * peers can read from incoming messages. */ n = KDBUS_ITEM_NEXT(n); - sprintf(n->str, "%lu-%s", (unsigned long) getuid(), name); + n->type = KDBUS_ITEM_ATTACH_FLAGS_RECV; + 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 = KDBUS_MAKE_POLICY_OPEN | (world ? KDBUS_MAKE_ACCESS_WORLD : 0); + make->flags = world ? KDBUS_MAKE_ACCESS_WORLD : 0; if (ioctl(fd, KDBUS_CMD_BUS_MAKE, make) < 0) { - close_nointr_nofail(fd); + safe_close(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); + p = strjoin("/sys/fs/kdbus/", n->str, "/bus", NULL); if (!p) { - close_nointr_nofail(fd); + safe_close(fd); return -ENOMEM; } @@ -1338,138 +1490,261 @@ int bus_kernel_create_bus(const char *name, bool world, char **s) { 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; +static int bus_kernel_translate_access(BusPolicyAccess access) { + assert(access >= 0); + assert(access < _BUS_POLICY_ACCESS_MAX); - assert(bus); - assert(name); + switch (access) { - 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); + case BUS_POLICY_ACCESS_SEE: + return KDBUS_POLICY_SEE; - fd = open(p, O_RDWR|O_NOCTTY|O_CLOEXEC); - if (fd < 0) - return -errno; + case BUS_POLICY_ACCESS_TALK: + return KDBUS_POLICY_TALK; - hello = alloca0(ALIGN8(offsetof(struct kdbus_cmd_hello, items) + - offsetof(struct kdbus_item, str) + - strlen(name) + 1)); + case BUS_POLICY_ACCESS_OWN: + return KDBUS_POLICY_OWN; - n = hello->items; - strcpy(n->str, name); - n->size = offsetof(struct kdbus_item, str) + strlen(n->str) + 1; - n->type = KDBUS_ITEM_NAME; + default: + assert_not_reached("Unknown policy access"); + } +} - hello->size = ALIGN8(offsetof(struct kdbus_cmd_hello, items) + n->size); - hello->conn_flags = KDBUS_HELLO_ACTIVATOR; - hello->pool_size = KDBUS_POOL_SIZE; +static int bus_kernel_translate_policy(const BusNamePolicy *policy, struct kdbus_item *item) { + int r; - if (ioctl(fd, KDBUS_CMD_HELLO, hello) < 0) { - close_nointr_nofail(fd); - return -errno; + assert(policy); + assert(item); + + switch (policy->type) { + + case BUSNAME_POLICY_TYPE_USER: { + const char *user = policy->name; + uid_t uid; + + r = get_user_creds(&user, &uid, NULL, NULL, NULL); + if (r < 0) + return r; + + item->policy_access.type = KDBUS_POLICY_ACCESS_USER; + item->policy_access.id = uid; + break; } - /* 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; + case BUSNAME_POLICY_TYPE_GROUP: { + const char *group = policy->name; + gid_t gid; + + r = get_group_creds(&group, &gid); + if (r < 0) + return r; + + item->policy_access.type = KDBUS_POLICY_ACCESS_GROUP; + item->policy_access.id = gid; + break; } - if (!bloom_validate_parameters((size_t) hello->bloom.size, (unsigned) hello->bloom.n_hash)) { - close_nointr_nofail(fd); - return -ENOTSUP; + default: + assert_not_reached("Unknown policy type"); + } + + item->policy_access.access = bus_kernel_translate_access(policy->access); + + return 0; +} + +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_create_domain(const char *name, char **s) { +int bus_kernel_create_endpoint(const char *bus_name, const char *ep_name, char **ep_path) { + _cleanup_free_ char *path = NULL; struct kdbus_cmd_make *make; struct kdbus_item *n; + const char *name; int fd; - assert(name); - assert(s); - - fd = open("/dev/kdbus/control", O_RDWR|O_NOCTTY|O_CLOEXEC); + fd = bus_kernel_open_bus_fd(bus_name, &path); if (fd < 0) - return -errno; + return fd; - make = alloca0(ALIGN8(offsetof(struct kdbus_cmd_make, items) + - offsetof(struct kdbus_item, str) + - strlen(name) + 1)); + make = alloca0_align(ALIGN8(offsetof(struct kdbus_cmd_make, items)) + + ALIGN8(offsetof(struct kdbus_item, str) + DECIMAL_STR_MAX(uid_t) + 1 + strlen(ep_name) + 1), + 8); + make->size = ALIGN8(offsetof(struct kdbus_cmd_make, items)); + make->flags = KDBUS_MAKE_ACCESS_WORLD; n = make->items; - strcpy(n->str, name); + sprintf(n->str, UID_FMT "-%s", getuid(), ep_name); n->size = offsetof(struct kdbus_item, str) + strlen(n->str) + 1; n->type = KDBUS_ITEM_MAKE_NAME; + make->size += ALIGN8(n->size); + name = n->str; - 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_DOMAIN_MAKE, make) < 0) { - close_nointr_nofail(fd); + if (ioctl(fd, KDBUS_CMD_ENDPOINT_MAKE, make) < 0) { + safe_close(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) { + if (ep_path) { char *p; - p = strappend("/dev/kdbus/domain/", name); + p = strjoin(dirname(path), "/", name, NULL); if (!p) { - close_nointr_nofail(fd); + safe_close(fd); return -ENOMEM; } - *s = p; + *ep_path = p; } return fd; } -int bus_kernel_create_monitor(const char *bus) { - struct kdbus_cmd_hello *hello; - char *p; - int fd; +int bus_kernel_set_endpoint_policy(int fd, uid_t uid, BusEndpoint *ep) { - assert(bus); + struct kdbus_cmd_update *update; + struct kdbus_item *n; + BusEndpointPolicy *po; + Iterator i; + size_t size; + int r; - 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); + size = ALIGN8(offsetof(struct kdbus_cmd_update, items)); - fd = open(p, O_RDWR|O_NOCTTY|O_CLOEXEC); - if (fd < 0) + HASHMAP_FOREACH(po, ep->policy_hash, i) { + size += ALIGN8(offsetof(struct kdbus_item, str) + strlen(po->name) + 1); + size += ALIGN8(offsetof(struct kdbus_item, policy_access) + sizeof(struct kdbus_policy_access)); + } + + update = alloca0_align(size, 8); + update->size = size; + + n = update->items; + + HASHMAP_FOREACH(po, ep->policy_hash, i) { + n->type = KDBUS_ITEM_NAME; + n->size = offsetof(struct kdbus_item, str) + strlen(po->name) + 1; + strcpy(n->str, po->name); + n = KDBUS_ITEM_NEXT(n); + + n->type = KDBUS_ITEM_POLICY_ACCESS; + n->size = offsetof(struct kdbus_item, policy_access) + sizeof(struct kdbus_policy_access); + + n->policy_access.type = KDBUS_POLICY_ACCESS_USER; + n->policy_access.access = bus_kernel_translate_access(po->access); + n->policy_access.id = uid; + + n = KDBUS_ITEM_NEXT(n); + } + + r = ioctl(fd, KDBUS_CMD_ENDPOINT_UPDATE, update); + if (r < 0) return -errno; - hello = alloca0(sizeof(struct kdbus_cmd_hello)); - hello->size = sizeof(struct kdbus_cmd_hello); - hello->conn_flags = KDBUS_HELLO_ACTIVATOR; + return 0; +} + +int bus_kernel_make_starter( + int fd, + const char *name, + bool activating, + bool accept_fd, + BusNamePolicy *policy, + BusPolicyAccess world_policy) { + + struct kdbus_cmd_hello *hello; + struct kdbus_item *n; + size_t policy_cnt = 0; + BusNamePolicy *po; + size_t size; + int r; + + assert(fd >= 0); + assert(name); + + LIST_FOREACH(policy, po, policy) + policy_cnt++; + + if (world_policy >= 0) + policy_cnt++; + + size = offsetof(struct kdbus_cmd_hello, items) + + ALIGN8(offsetof(struct kdbus_item, str) + strlen(name) + 1) + + policy_cnt * ALIGN8(offsetof(struct kdbus_item, policy_access) + sizeof(struct kdbus_policy_access)); + + hello = alloca0_align(size, 8); + + n = hello->items; + strcpy(n->str, name); + n->size = offsetof(struct kdbus_item, str) + strlen(n->str) + 1; + n->type = KDBUS_ITEM_NAME; + n = KDBUS_ITEM_NEXT(n); + + LIST_FOREACH(policy, po, policy) { + n->type = KDBUS_ITEM_POLICY_ACCESS; + n->size = offsetof(struct kdbus_item, policy_access) + sizeof(struct kdbus_policy_access); + + r = bus_kernel_translate_policy(po, n); + if (r < 0) + return r; + + n = KDBUS_ITEM_NEXT(n); + } + + if (world_policy >= 0) { + n->type = KDBUS_ITEM_POLICY_ACCESS; + n->size = offsetof(struct kdbus_item, policy_access) + sizeof(struct kdbus_policy_access); + n->policy_access.type = KDBUS_POLICY_ACCESS_WORLD; + n->policy_access.access = bus_kernel_translate_access(world_policy); + } + + hello->size = size; + hello->flags = + (activating ? KDBUS_HELLO_ACTIVATOR : KDBUS_HELLO_POLICY_HOLDER) | + (accept_fd ? KDBUS_HELLO_ACCEPT_FD : 0); hello->pool_size = KDBUS_POOL_SIZE; + hello->attach_flags_send = _KDBUS_ATTACH_ANY; + hello->attach_flags_recv = _KDBUS_ATTACH_ANY; - if (ioctl(fd, KDBUS_CMD_HELLO, hello) < 0) { - close_nointr_nofail(fd); + if (ioctl(fd, KDBUS_CMD_HELLO, hello) < 0) return -errno; - } - /* The higher 32bit of both flags fields are considered + /* The higher 32bit of the bus_flags fields are considered * 'incompatible flags'. Refuse them all for now. */ - if (hello->bus_flags > 0xFFFFFFFFULL || - hello->conn_flags > 0xFFFFFFFFULL) { - close_nointr_nofail(fd); + if (hello->bus_flags > 0xFFFFFFFFULL) + return -ENOTSUP; + + if (!bloom_validate_parameters((size_t) hello->bloom.size, (unsigned) hello->bloom.n_hash)) return -ENOTSUP; - } return fd; } @@ -1496,3 +1771,66 @@ int bus_kernel_drop_one(int fd) { return 0; } + +int bus_kernel_realize_attach_flags(sd_bus *bus) { + struct kdbus_cmd_update *update; + struct kdbus_item *n; + + assert(bus); + assert(bus->is_kernel); + + update = alloca0_align(offsetof(struct kdbus_cmd_update, 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_update, items) + + ALIGN8(n->size); + + if (ioctl(bus->input_fd, KDBUS_CMD_CONN_UPDATE, update) < 0) + return -errno; + + return 0; +} + +int bus_kernel_fix_attach_mask(void) { + _cleanup_free_ char *mask = NULL; + uint64_t m = (uint64_t) -1; + char buf[2+16+2]; + int r; + + /* By default we don't want any kdbus metadata fields to be + * suppressed, hence we reset the kernel mask for it to + * (uint64_t) -1. This is overridable via a kernel command + * line option, however. */ + + r = get_proc_cmdline_key("systemd.kdbus_attach_flags_mask=", &mask); + if (r < 0) { + log_warning_errno(-r, "Failed to read kernel command line: %m"); + return r; + } + + if (mask) { + const char *p = mask; + + if (startswith(p, "0x")) + p += 2; + + if (sscanf(p, "%" PRIx64, &m) != 1) + log_warning("Couldn't parse systemd.kdbus_attach_flags_mask= kernel command line parameter."); + } + + sprintf(buf, "0x%" PRIx64 "\n", m); + r = write_string_file("/sys/module/kdbus/parameters/attach_flags_mask", buf); + if (r < 0) { + log_warning_errno(-r, "Failed to write kdbus attach mask: %m"); + return r; + } + + return 0; +}