| /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ |
| |
| /*** |
| This file is part of systemd. |
| |
| Copyright 2013 Lennart Poettering |
| |
| systemd is free software; you can redistribute it and/or modify it |
| under the terms of the GNU Lesser General Public License as published by |
| the Free Software Foundation; either version 2.1 of the License, or |
| (at your option) any later version. |
| |
| systemd is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with systemd; If not, see <http://www.gnu.org/licenses/>. |
| ***/ |
| |
| #ifdef HAVE_VALGRIND_MEMCHECK_H |
| #include <valgrind/memcheck.h> |
| #endif |
| |
| #include <fcntl.h> |
| #include <malloc.h> |
| |
| #include "util.h" |
| |
| #include "bus-internal.h" |
| #include "bus-message.h" |
| #include "bus-kernel.h" |
| #include "bus-bloom.h" |
| |
| #define KDBUS_ITEM_NEXT(item) \ |
| (typeof(item))(((uint8_t *)item) + ALIGN8((item)->size)) |
| |
| #define KDBUS_ITEM_FOREACH(item, head) \ |
| for (item = (head)->items; \ |
| (uint8_t *)(item) < (uint8_t *)(head) + (head)->size; \ |
| item = KDBUS_ITEM_NEXT(item)) |
| |
| #define KDBUS_ITEM_HEADER_SIZE offsetof(struct kdbus_item, data) |
| #define KDBUS_ITEM_SIZE(s) ALIGN8((s) + KDBUS_ITEM_HEADER_SIZE) |
| |
| static int 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(p); |
| assert(sz > 0); |
| |
| *d = ALIGN8_PTR(*d); |
| |
| (*d)->size = offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec); |
| (*d)->type = KDBUS_MSG_PAYLOAD_VEC; |
| (*d)->vec.address = (intptr_t) p; |
| (*d)->vec.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_MSG_DST_NAME; |
| memcpy((*d)->str, s, length + 1); |
| |
| *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size); |
| } |
| |
| static void* append_bloom(struct kdbus_item **d, size_t length) { |
| void *r; |
| |
| assert(d); |
| |
| *d = ALIGN8_PTR(*d); |
| |
| (*d)->size = offsetof(struct kdbus_item, data) + length; |
| (*d)->type = KDBUS_MSG_BLOOM; |
| r = (*d)->data; |
| |
| *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size); |
| |
| return r; |
| } |
| |
| static void append_fds(struct kdbus_item **d, const int fds[], unsigned n_fds) { |
| assert(d); |
| assert(fds); |
| assert(n_fds > 0); |
| |
| *d = ALIGN8_PTR(*d); |
| (*d)->size = offsetof(struct kdbus_item, fds) + sizeof(int) * n_fds; |
| (*d)->type = KDBUS_MSG_UNIX_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_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 kdbus_item *d; |
| bool well_known; |
| uint64_t unique; |
| size_t sz, dl; |
| int r; |
| |
| assert(b); |
| assert(m); |
| assert(m->sealed); |
| |
| if (m->kdbus) |
| return 0; |
| |
| if (m->destination) { |
| r = parse_unique_name(m->destination, &unique); |
| if (r < 0) |
| return r; |
| |
| well_known = r == 0; |
| } else |
| well_known = false; |
| |
| sz = offsetof(struct kdbus_msg, items); |
| |
| /* Add in fixed header, fields header and payload */ |
| sz += 3 * ALIGN8(offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec)); |
| |
| /* Add space for bloom filter */ |
| sz += ALIGN8(offsetof(struct kdbus_item, data) + BLOOM_SIZE); |
| |
| /* Add in well-known destination header */ |
| if (well_known) { |
| dl = strlen(m->destination); |
| sz += ALIGN8(offsetof(struct kdbus_item, str) + dl + 1); |
| } |
| |
| /* Add space for unix fds */ |
| if (m->n_fds > 0) |
| sz += ALIGN8(offsetof(struct kdbus_item, fds) + sizeof(int)*m->n_fds); |
| |
| m->kdbus = memalign(8, sz); |
| if (!m->kdbus) |
| return -ENOMEM; |
| |
| 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 : 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->items; |
| |
| if (well_known) |
| append_destination(&d, m->destination, dl); |
| |
| append_payload_vec(&d, m->header, sizeof(*m->header)); |
| |
| if (m->fields) |
| append_payload_vec(&d, m->fields, ALIGN8(m->header->fields_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) { |
| free(m->kdbus); |
| m->kdbus = NULL; |
| return -r; |
| } |
| } |
| |
| 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; |
| } |
| |
| int bus_kernel_take_fd(sd_bus *b) { |
| struct kdbus_cmd_hello hello = { |
| .conn_flags = |
| KDBUS_HELLO_ACCEPT_FD| |
| KDBUS_HELLO_ATTACH_COMM| |
| KDBUS_HELLO_ATTACH_EXE| |
| KDBUS_HELLO_ATTACH_CMDLINE| |
| KDBUS_HELLO_ATTACH_CGROUP| |
| KDBUS_HELLO_ATTACH_CAPS| |
| KDBUS_HELLO_ATTACH_SECLABEL| |
| KDBUS_HELLO_ATTACH_AUDIT |
| }; |
| int r; |
| |
| assert(b); |
| |
| if (b->is_server) |
| return -EINVAL; |
| |
| r = ioctl(b->input_fd, KDBUS_CMD_HELLO, &hello); |
| if (r < 0) |
| 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->is_kernel = true; |
| b->bus_client = true; |
| b->can_fds = true; |
| |
| r = bus_start_running(b); |
| if (r < 0) |
| return r; |
| |
| return 1; |
| } |
| |
| int bus_kernel_connect(sd_bus *b) { |
| assert(b); |
| assert(b->input_fd < 0); |
| assert(b->output_fd < 0); |
| assert(b->kernel); |
| |
| if (b->is_server) |
| return -EINVAL; |
| |
| b->input_fd = open(b->kernel, O_RDWR|O_NOCTTY|O_CLOEXEC); |
| if (b->input_fd < 0) |
| return -errno; |
| |
| b->output_fd = b->input_fd; |
| |
| return bus_kernel_take_fd(b); |
| } |
| |
| int bus_kernel_write_message(sd_bus *bus, sd_bus_message *m) { |
| int r; |
| |
| assert(bus); |
| assert(m); |
| assert(bus->state == BUS_RUNNING); |
| |
| 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) |
| return errno == EAGAIN ? 0 : -errno; |
| |
| return 1; |
| } |
| |
| static void close_kdbus_msg(struct kdbus_msg *k) { |
| struct kdbus_item *d; |
| |
| KDBUS_ITEM_FOREACH(d, k) { |
| |
| if (d->type != KDBUS_MSG_UNIX_FDS) |
| continue; |
| |
| close_many(d->fds, (d->size - offsetof(struct kdbus_item, fds)) / sizeof(int)); |
| } |
| } |
| |
| static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_message **ret) { |
| sd_bus_message *m = NULL; |
| struct kdbus_item *d; |
| unsigned n_payload = 0, n_fds = 0; |
| _cleanup_free_ int *fds = NULL; |
| struct bus_header *h = NULL; |
| size_t total, n_bytes = 0, idx = 0; |
| const char *destination = NULL, *seclabel = NULL; |
| int r; |
| |
| assert(bus); |
| assert(k); |
| assert(ret); |
| |
| if (k->payload_type != KDBUS_PAYLOAD_DBUS1) |
| return 0; |
| |
| KDBUS_ITEM_FOREACH(d, k) { |
| size_t l; |
| |
| l = d->size - offsetof(struct kdbus_item, data); |
| |
| if (d->type == KDBUS_MSG_PAYLOAD) { |
| |
| if (!h) { |
| if (l < sizeof(struct bus_header)) |
| return -EBADMSG; |
| |
| h = (struct bus_header*) d->data; |
| } |
| |
| n_payload++; |
| n_bytes += l; |
| |
| } else if (d->type == KDBUS_MSG_UNIX_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; |
| |
| } else if (d->type == KDBUS_MSG_DST_NAME) |
| destination = d->str; |
| else if (d->type == KDBUS_MSG_SRC_SECLABEL) |
| seclabel = d->str; |
| } |
| |
| if (!h) |
| return -EBADMSG; |
| |
| r = bus_header_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, seclabel, 0, &m); |
| if (r < 0) |
| return r; |
| |
| KDBUS_ITEM_FOREACH(d, k) { |
| size_t l; |
| |
| l = d->size - offsetof(struct kdbus_item, data); |
| |
| if (d->type == KDBUS_MSG_PAYLOAD) { |
| |
| if (idx == sizeof(struct bus_header) && |
| l == ALIGN8(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))) { |
| sd_bus_message_unref(m); |
| return -EBADMSG; |
| } |
| |
| idx += l; |
| } else if (d->type == KDBUS_MSG_SRC_CREDS) { |
| m->pid_starttime = d->creds.starttime / NSEC_PER_USEC; |
| m->uid = d->creds.uid; |
| m->gid = d->creds.gid; |
| m->pid = d->creds.pid; |
| m->tid = d->creds.tid; |
| m->uid_valid = m->gid_valid = true; |
| } else if (d->type == KDBUS_MSG_TIMESTAMP) { |
| m->realtime = d->timestamp.realtime_ns / NSEC_PER_USEC; |
| m->monotonic = d->timestamp.monotonic_ns / NSEC_PER_USEC; |
| } else if (d->type == KDBUS_MSG_SRC_PID_COMM) |
| m->comm = d->str; |
| else if (d->type == KDBUS_MSG_SRC_TID_COMM) |
| m->tid_comm = d->str; |
| else if (d->type == KDBUS_MSG_SRC_EXE) |
| m->exe = d->str; |
| else if (d->type == KDBUS_MSG_SRC_CMDLINE) { |
| m->cmdline = d->str; |
| m->cmdline_length = l; |
| } else if (d->type == KDBUS_MSG_SRC_CGROUP) |
| m->cgroup = d->str; |
| else if (d->type == KDBUS_MSG_SRC_AUDIT) |
| m->audit = &d->audit; |
| else if (d->type == KDBUS_MSG_SRC_CAPS) { |
| m->capability = d->data; |
| m->capability_size = l; |
| } else |
| 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 (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->free_fds = true; |
| |
| fds = NULL; |
| |
| *ret = m; |
| return 1; |
| } |
| |
| int bus_kernel_read_message(sd_bus *bus, sd_bus_message **m) { |
| struct kdbus_msg *k; |
| size_t sz = 1024; |
| int r; |
| |
| assert(bus); |
| assert(m); |
| |
| for (;;) { |
| void *q; |
| |
| q = memalign(8, sz); |
| if (!q) |
| return -errno; |
| |
| free(bus->rbuffer); |
| k = bus->rbuffer = q; |
| k->size = sz; |
| |
| /* Let's tell valgrind that there's really no need to |
| * initialize this fully. This should be removed again |
| * when valgrind learned the kdbus ioctls natively. */ |
| #ifdef HAVE_VALGRIND_MEMCHECK_H |
| VALGRIND_MAKE_MEM_DEFINED(k, sz); |
| #endif |
| |
| r = ioctl(bus->input_fd, KDBUS_CMD_MSG_RECV, bus->rbuffer); |
| if (r >= 0) |
| break; |
| |
| if (errno == EAGAIN) |
| return 0; |
| |
| if (errno != ENOBUFS) |
| return -errno; |
| |
| sz *= 2; |
| } |
| |
| r = bus_kernel_make_message(bus, k, m); |
| if (r > 0) |
| bus->rbuffer = NULL; |
| else |
| close_kdbus_msg(k); |
| |
| return r < 0 ? r : 1; |
| } |
| |
| int bus_kernel_create(const char *name, char **s) { |
| struct kdbus_cmd_bus_make *make; |
| struct kdbus_item *n, *cg; |
| size_t l; |
| int fd; |
| char *p; |
| |
| assert(name); |
| assert(s); |
| |
| fd = open("/dev/kdbus/control", O_RDWR|O_NOCTTY|O_CLOEXEC); |
| if (fd < 0) |
| return -errno; |
| |
| l = strlen(name); |
| make = alloca0(offsetof(struct kdbus_cmd_bus_make, items) + |
| KDBUS_ITEM_HEADER_SIZE + sizeof(uint64_t) + |
| KDBUS_ITEM_HEADER_SIZE + DECIMAL_STR_MAX(uid_t) + 1 + l + 1); |
| |
| cg = make->items; |
| cg->type = KDBUS_MAKE_CGROUP; |
| cg->data64[0] = 1; |
| cg->size = KDBUS_ITEM_HEADER_SIZE + sizeof(uint64_t); |
| |
| n = KDBUS_ITEM_NEXT(cg); |
| n->type = KDBUS_MAKE_NAME; |
| sprintf(n->str, "%lu-%s", (unsigned long) getuid(), name); |
| n->size = KDBUS_ITEM_HEADER_SIZE + strlen(n->str) + 1; |
| |
| make->size = offsetof(struct kdbus_cmd_bus_make, items) + cg->size + n->size; |
| make->flags = KDBUS_MAKE_ACCESS_WORLD | 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, make) < 0) { |
| close_nointr_nofail(fd); |
| free(p); |
| return -errno; |
| } |
| |
| if (s) |
| *s = p; |
| |
| return fd; |
| } |