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=54e85c94439f2fbec5415e797aa4f8db574b9b0d;hp=e329b14be819d43f16cc5287ba97cb10ab7367ac;hb=7d22c717329c6317f97ccd0f68040a3a2b98e760;hpb=18cd014f13cb988037acc16f8150b8f6d7042cd5 diff --git a/src/libsystemd-bus/bus-kernel.c b/src/libsystemd-bus/bus-kernel.c index e329b14be..54e85c944 100644 --- a/src/libsystemd-bus/bus-kernel.c +++ b/src/libsystemd-bus/bus-kernel.c @@ -33,21 +33,11 @@ #include "bus-message.h" #include "bus-kernel.h" #include "bus-bloom.h" +#include "bus-util.h" -#define KDBUS_ITEM_NEXT(item) \ - (typeof(item))(((uint8_t *)item) + ALIGN8((item)->size)) +#define UNIQUE_NAME_MAX (3+DECIMAL_STR_MAX(uint64_t)) -#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) - -#define KDBUS_POOL_SIZE (4*1024*1024) - -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); @@ -65,19 +55,36 @@ static int parse_unique_name(const char *s, uint64_t *id) { 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); + /* 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_MSG_PAYLOAD_VEC; - (*d)->vec.address = (uint64_t) p; + (*d)->type = KDBUS_ITEM_PAYLOAD_VEC; + (*d)->vec.address = PTR_TO_UINT64(p); (*d)->vec.size = sz; *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size); } +static void append_payload_memfd(struct kdbus_item **d, int memfd, size_t 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_item **d, const char *s, size_t length) { assert(d); assert(s); @@ -85,7 +92,7 @@ static void append_destination(struct kdbus_item **d, const char *s, size_t leng *d = ALIGN8_PTR(*d); (*d)->size = offsetof(struct kdbus_item, str) + length + 1; - (*d)->type = KDBUS_MSG_DST_NAME; + (*d)->type = KDBUS_ITEM_DST_NAME; memcpy((*d)->str, s, length + 1); *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size); @@ -99,7 +106,7 @@ static void* append_bloom(struct kdbus_item **d, size_t length) { *d = ALIGN8_PTR(*d); (*d)->size = offsetof(struct kdbus_item, data) + length; - (*d)->type = KDBUS_MSG_BLOOM; + (*d)->type = KDBUS_ITEM_BLOOM; r = (*d)->data; *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size); @@ -114,7 +121,7 @@ static void append_fds(struct kdbus_item **d, const int fds[], unsigned n_fds) { *d = ALIGN8_PTR(*d); (*d)->size = offsetof(struct kdbus_item, fds) + sizeof(int) * n_fds; - (*d)->type = KDBUS_MSG_FDS; + (*d)->type = KDBUS_ITEM_FDS; memcpy((*d)->fds, fds, sizeof(int) * n_fds); *d = (struct kdbus_item *) ((uint8_t*) *d + (*d)->size); @@ -137,6 +144,7 @@ static int bus_message_setup_bloom(sd_bus_message *m, void *bloom) { 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, '/'); } @@ -184,10 +192,12 @@ static int bus_message_setup_bloom(sd_bus_message *m, void *bloom) { } 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); @@ -198,7 +208,7 @@ static int bus_message_setup_kmsg(sd_bus *b, 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; @@ -208,8 +218,12 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) { 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 += 3 * ALIGN8(offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec)); + sz += (1 + m->n_body_parts) * + ALIGN8(offsetof(struct kdbus_item, vec) + sizeof(struct kdbus_vec)); /* Add space for bloom filter */ sz += ALIGN8(offsetof(struct kdbus_item, data) + BLOOM_SIZE); @@ -225,9 +239,12 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) { sz += ALIGN8(offsetof(struct kdbus_item, fds) + sizeof(int)*m->n_fds); m->kdbus = memalign(8, sz); - if (!m->kdbus) - return -ENOMEM; + if (!m->kdbus) { + r = -ENOMEM; + goto fail; + } + m->free_kdbus = true; memset(m->kdbus, 0, sz); m->kdbus->flags = @@ -246,24 +263,43 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) { 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, ALIGN8(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 */ - if (m->body) - append_payload_vec(&d, m->body, m->header->body_size); + append_payload_vec(&d, NULL, part->size); + continue; + } + + 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_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->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 (r < 0) + goto fail; } if (m->n_fds > 0) @@ -272,18 +308,15 @@ static int bus_message_setup_kmsg(sd_bus *b, sd_bus_message *m) { 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) { - uint8_t h[ALIGN8(sizeof(struct kdbus_cmd_hello)) + - ALIGN8(KDBUS_ITEM_HEADER_SIZE) + - ALIGN8(sizeof(struct kdbus_vec))] = {}; - - struct kdbus_cmd_hello *hello = (struct kdbus_cmd_hello*) h; - + struct kdbus_cmd_hello hello; int r; assert(b); @@ -291,49 +324,44 @@ int bus_kernel_take_fd(sd_bus *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|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); + 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; } } - hello->size = sizeof(h); - 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; - - hello->items[0].type = KDBUS_HELLO_POOL; - hello->items[0].size = KDBUS_ITEM_HEADER_SIZE + sizeof(struct kdbus_vec); - hello->items[0].vec.address = (uint64_t) b->kdbus_buffer; - hello->items[0].vec.size = KDBUS_POOL_SIZE; - - 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) + 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->is_kernel = true; b->bus_client = true; - b->can_fds = true; + b->can_fds = !!(hello.conn_flags & KDBUS_HELLO_ACCEPT_FD); + + /* the kernel told us the UUID of the underlying bus */ + memcpy(b->server_id.bytes, hello.id128, sizeof(b->server_id.bytes)); r = bus_start_running(b); if (r < 0) @@ -379,39 +407,200 @@ int bus_kernel_write_message(sd_bus *bus, sd_bus_message *m) { } static void close_kdbus_msg(sd_bus *bus, struct kdbus_msg *k) { + uint64_t off; struct kdbus_item *d; assert(bus); assert(k); - ioctl(bus->input_fd, KDBUS_CMD_MSG_RELEASE, k); + off = (uint8_t *)k - (uint8_t *)bus->kdbus_buffer; + ioctl(bus->input_fd, KDBUS_CMD_MSG_RELEASE, &off); - KDBUS_ITEM_FOREACH(d, k) { + KDBUS_PART_FOREACH(d, k, items) { - if (d->type != KDBUS_MSG_FDS) - continue; + 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; - close_many(d->fds, (d->size - offsetof(struct kdbus_item, fds)) / sizeof(int)); + assert(bus); + + r = sd_bus_message_new_signal( + bus, + "/org/freedesktop/DBus", + "org.freedesktop.DBus", + "NameOwnerChanged", + &m); + if (r < 0) + return r; + + 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_message(bus, m); + if (r < 0) + return r; + + r = bus_rqueue_push(bus, m); + if (r < 0) + return r; + + m = NULL; + return 1; +} + +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); + + if (d->name_change.flags != 0) + return 0; + + 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; + + m->sender = "org.freedesktop.DBus"; + + r = bus_seal_message(bus, m); + if (r < 0) + return r; + + r = bus_rqueue_push(bus, m); + if (r < 0) + return r; + + 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](bus, k, d); } -static bool range_contains(size_t astart, size_t asize, size_t bstart, size_t bsize, void *a, void **b) { +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)); - if (bstart < astart) - return false; + 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))); - if (bstart + bsize > astart + asize) - return false; + 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))); - *b = (uint8_t*) a + (bstart - astart); + SET_FLAG(m, KDBUS_ATTACH_SECLABEL, + !!(mask & SD_BUS_CREDS_SELINUX_CONTEXT)); - return true; + 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 **ret) { +static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k) { sd_bus_message *m = NULL; struct kdbus_item *d; - unsigned n_payload = 0, n_fds = 0; + unsigned n_fds = 0; _cleanup_free_ int *fds = NULL; struct bus_header *h = NULL; size_t total, n_bytes = 0, idx = 0; @@ -420,29 +609,34 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_mess assert(bus); assert(k); - assert(ret); - - if (k->payload_type != KDBUS_PAYLOAD_DBUS1) - return 0; + assert(k->payload_type == KDBUS_PAYLOAD_DBUS1); - KDBUS_ITEM_FOREACH(d, k) { + KDBUS_PART_FOREACH(d, k, items) { size_t l; l = d->size - offsetof(struct kdbus_item, data); - if (d->type == KDBUS_MSG_PAYLOAD_VEC) { + switch (d->type) { + case KDBUS_ITEM_PAYLOAD_OFF: if (!h) { - if (d->vec.size < sizeof(struct bus_header)) - return -EBADMSG; + h = (struct bus_header *)((uint8_t *)bus->kdbus_buffer + d->vec.offset); - h = (struct bus_header*)(uintptr_t) d->vec.address; + if (!bus_header_is_complete(h, d->vec.size)) + return -EBADMSG; } - n_payload++; n_bytes += d->vec.size; + break; - } else if (d->type == KDBUS_MSG_FDS) { + case KDBUS_ITEM_PAYLOAD_MEMFD: + if (!h) + return -EBADMSG; + + n_bytes += d->memfd.size; + break; + + case KDBUS_ITEM_FDS: { int *f; unsigned j; @@ -454,87 +648,163 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_mess fds = f; memcpy(fds + n_fds, d->fds, sizeof(int) * j); n_fds += j; + break; + } - } else if (d->type == KDBUS_MSG_DST_NAME) - destination = d->str; - else if (d->type == KDBUS_MSG_SRC_SECLABEL) + 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; - //if (n_payload > 2) - // return -EBADMSG; - - r = bus_message_from_header(h, sizeof(struct bus_header), fds, n_fds, NULL, seclabel, 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_ITEM_FOREACH(d, k) { + KDBUS_PART_FOREACH(d, k, items) { size_t l; l = d->size - offsetof(struct kdbus_item, data); - if (d->type == KDBUS_MSG_PAYLOAD_VEC) { + switch (d->type) { - range_contains(idx, d->vec.size, ALIGN8(sizeof(struct bus_header)), BUS_MESSAGE_FIELDS_SIZE(m), - (void *)(uintptr_t) d->vec.address, &m->fields); - range_contains(idx, d->vec.size, ALIGN8(sizeof(struct bus_header)) + ALIGN8(BUS_MESSAGE_FIELDS_SIZE(m)), - BUS_MESSAGE_BODY_SIZE(m), (void *)(uintptr_t) d->vec.address, &m->body); + case KDBUS_ITEM_PAYLOAD_OFF: { + size_t begin_body; + + begin_body = BUS_MESSAGE_BODY_BEGIN(m); + + if (idx + d->vec.size > begin_body) { + struct bus_body_part *part; + + /* Contains body material */ + + part = message_append_part(m); + if (!part) { + r = -ENOMEM; + goto fail; + } + + /* A -1 offset is NUL padding. */ + part->is_zero = d->vec.offset == ~0ULL; + + if (idx >= begin_body) { + if (!part->is_zero) + part->data = (uint8_t *)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; + } + + 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; - } 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) { + 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; - } 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 if (d->type != KDBUS_MSG_FDS && - d->type != KDBUS_MSG_DST_NAME && - d->type != KDBUS_MSG_SRC_SECLABEL) - log_debug("Got unknown field from kernel %llu", d->type); - } + break; - if ((BUS_MESSAGE_FIELDS_SIZE(m) > 0 && !m->fields) || - (BUS_MESSAGE_BODY_SIZE(m) > 0 && !m->body)) { - sd_bus_message_unref(m); - return -EBADMSG; + 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; + + 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"; @@ -555,41 +825,65 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_mess /* We take possession of the kmsg struct now */ m->kdbus = k; - m->bus = sd_bus_ref(bus); m->release_kdbus = true; m->free_fds = true; fds = NULL; - *ret = m; + r = bus_rqueue_push(bus, m); + if (r < 0) + goto fail; + 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; + uint64_t off; int r; assert(bus); - assert(m); - r = ioctl(bus->input_fd, KDBUS_CMD_MSG_RECV, &k); + /* Kernel messages might result in 2 new queued messages in + * the worst case (NameOwnerChange and LostName for the same + * well-known name, for example). Let's make room in + * advance. */ + + r = bus_rqueue_make_room(bus, 2); + if (r < 0) + return r; + + r = ioctl(bus->input_fd, KDBUS_CMD_MSG_RECV, &off); if (r < 0) { if (errno == EAGAIN) return 0; return -errno; } + k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + off); + 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 + r = 0; -/* /\* 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 = bus_kernel_make_message(bus, k, m); if (r <= 0) close_kdbus_msg(bus, k); @@ -598,7 +892,7 @@ int bus_kernel_read_message(sd_bus *bus, sd_bus_message **m) { int bus_kernel_create(const char *name, char **s) { struct kdbus_cmd_bus_make *make; - struct kdbus_item *n, *cg; + struct kdbus_item *n; size_t l; int fd; char *p; @@ -612,20 +906,15 @@ int bus_kernel_create(const char *name, char **s) { 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); + KDBUS_PART_HEADER_SIZE + sizeof(uint64_t) + + KDBUS_PART_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 = make->items; n->type = KDBUS_MAKE_NAME; sprintf(n->str, "%lu-%s", (unsigned long) getuid(), name); - n->size = KDBUS_ITEM_HEADER_SIZE + strlen(n->str) + 1; + n->size = KDBUS_PART_HEADER_SIZE + strlen(n->str) + 1; - make->size = offsetof(struct kdbus_cmd_bus_make, items) + cg->size + n->size; + 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; @@ -646,3 +935,113 @@ 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; +}