summaryrefslogtreecommitdiff
path: root/src/libsystemd-bus
diff options
context:
space:
mode:
Diffstat (limited to 'src/libsystemd-bus')
-rw-r--r--src/libsystemd-bus/bus-control.c219
-rw-r--r--src/libsystemd-bus/bus-internal.h2
-rw-r--r--src/libsystemd-bus/bus-kernel.c224
-rw-r--r--src/libsystemd-bus/sd-bus.c2
4 files changed, 416 insertions, 31 deletions
diff --git a/src/libsystemd-bus/bus-control.c b/src/libsystemd-bus/bus-control.c
index 08c0f49360..988d4265ff 100644
--- a/src/libsystemd-bus/bus-control.c
+++ b/src/libsystemd-bus/bus-control.c
@@ -416,6 +416,183 @@ _public_ int sd_bus_get_owner(
return 0;
}
+static int add_name_change_match(sd_bus *bus,
+ uint64_t cookie,
+ const char *name,
+ const char *old_owner,
+ const char *new_owner) {
+
+ uint64_t name_id = 0, old_owner_id = 0, new_owner_id = 0;
+ int is_name_id = -1, r;
+ struct kdbus_item *item;
+
+ assert(bus);
+
+ /* If we encounter a match that could match against
+ * NameOwnerChanged messages, then we need to create
+ * KDBUS_MATCH_NAME_{ADD,REMOVE,CHANGE} and
+ * KDBUS_MATCH_ID_{ADD,REMOVE} matches for it, possibly
+ * multiple if the match is underspecified.
+ *
+ * The NameOwnerChanged signals take three parameters with
+ * unique or well-known names, but only some forms actually
+ * exist:
+ *
+ * WELLKNOWN, "", UNIQUE → KDBUS_MATCH_NAME_ADD
+ * WELLKNOWN, UNIQUE, "" → KDBUS_MATCH_NAME_REMOVE
+ * WELLKNOWN, UNIQUE, UNIQUE → KDBUS_MATCH_NAME_CHANGE
+ * UNIQUE, "", UNIQUE → KDBUS_MATCH_ID_ADD
+ * UNIQUE, UNIQUE, "" → KDBUS_MATCH_ID_REMOVE
+ *
+ * For the latter two the two unique names must be identical.
+ *
+ * */
+
+ if (name) {
+ is_name_id = bus_kernel_parse_unique_name(name, &name_id);
+ if (is_name_id < 0)
+ return 0;
+ }
+
+ if (old_owner) {
+ r = bus_kernel_parse_unique_name(old_owner, &old_owner_id);
+ if (r < 0)
+ return 0;
+ if (r == 0)
+ return 0;
+ if (is_name_id > 0 && old_owner_id != name_id)
+ return 0;
+ }
+
+ if (new_owner) {
+ r = bus_kernel_parse_unique_name(new_owner, &new_owner_id);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return 0;
+ if (is_name_id > 0 && new_owner_id != name_id)
+ return 0;
+ }
+
+ if (is_name_id <= 0) {
+ size_t sz, l;
+
+ /* If the name argument is missing or is a well-known
+ * name, then add KDBUS_MATCH_NAME_{ADD,REMOVE,CHANGE}
+ * matches for it */
+
+ l = name ? strlen(name) : 0;
+
+ sz = ALIGN8(offsetof(struct kdbus_cmd_match, items) +
+ offsetof(struct kdbus_item, name_change) +
+ offsetof(struct kdbus_notify_name_change, name) +
+ l+1);
+
+ {
+ union {
+ uint8_t buffer[sz];
+ struct kdbus_cmd_match match;
+ } m;
+
+ memzero(&m, sz);
+
+ m.match.size = sz;
+ m.match.cookie = cookie;
+ m.match.src_id = KDBUS_SRC_ID_KERNEL;
+
+ item = m.match.items;
+ item->size =
+ offsetof(struct kdbus_item, name_change) +
+ offsetof(struct kdbus_notify_name_change, name) +
+ l+1;
+
+ item->name_change.old_id = old_owner_id;
+ item->name_change.new_id = new_owner_id;
+
+ if (name)
+ strcpy(item->name_change.name, name);
+
+ /* If the old name is unset or empty, then
+ * this can match against added names */
+ if (!old_owner || old_owner[0] == 0) {
+ item->type = KDBUS_MATCH_NAME_ADD;
+
+ r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_ADD, m);
+ if (r < 0)
+ return -errno;
+ }
+
+ /* If the new name is unset or empty, then
+ * this can match against removed names */
+ if (!new_owner || new_owner[0] == 0) {
+ item->type = KDBUS_MATCH_NAME_REMOVE;
+
+ r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_ADD, m);
+ if (r < 0)
+ return -errno;
+ }
+
+ /* If the neither name is explicitly set to
+ * the empty string, then this can match
+ * agains changed names */
+ if (!(old_owner && old_owner[0] == 0) &&
+ !(new_owner && new_owner[0] == 0)) {
+ item->type = KDBUS_MATCH_NAME_CHANGE;
+
+ r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_ADD, m);
+ if (r < 0)
+ return -errno;
+ }
+ }
+ }
+
+ if (is_name_id != 0) {
+ uint64_t sz =
+ ALIGN8(offsetof(struct kdbus_cmd_match, items) +
+ offsetof(struct kdbus_item, id_change));
+ union {
+ uint8_t buffer[sz];
+ struct kdbus_cmd_match match;
+ } m;
+
+ /* If the name argument is missing or is a unique
+ * name, then add KDBUS_MATCH_ID_{ADD,REMOVE} matches
+ * for it */
+
+ memzero(&m, sz);
+
+ m.match.size = sz;
+ m.match.cookie = cookie;
+ m.match.src_id = KDBUS_SRC_ID_KERNEL;
+
+ item = m.match.items;
+ item->size = offsetof(struct kdbus_item, id_change) + sizeof(struct kdbus_notify_id_change);
+ item->id_change.id = name_id;
+
+ /* If the old name is unset or empty, then this can
+ * match against added ids */
+ if (!old_owner || old_owner[0] == 0) {
+ item->type = KDBUS_MATCH_ID_ADD;
+
+ r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_ADD, m);
+ if (r < 0)
+ return -errno;
+ }
+
+ /* If thew new name is unset or empty, then this can
+ match against removed ids */
+ if (!new_owner || new_owner[0] == 0) {
+ item->type = KDBUS_MATCH_ID_REMOVE;
+
+ r = ioctl(bus->input_fd, KDBUS_CMD_MATCH_ADD, m);
+ if (r < 0)
+ return -errno;
+ }
+ }
+
+ return 0;
+}
+
int bus_add_match_internal(
sd_bus *bus,
const char *match,
@@ -438,6 +615,8 @@ int bus_add_match_internal(
uint64_t src_id = KDBUS_MATCH_SRC_ID_ANY;
bool using_bloom = false;
unsigned i;
+ bool matches_name_change = true;
+ const char *name_change_arg[3] = {};
zero(bloom);
@@ -449,6 +628,9 @@ int bus_add_match_internal(
switch (c->type) {
case BUS_MATCH_SENDER:
+ if (!streq(c->value_str, "org.freedesktop.DBus"))
+ matches_name_change = false;
+
r = bus_kernel_parse_unique_name(c->value_str, &src_id);
if (r < 0)
return r;
@@ -462,21 +644,33 @@ int bus_add_match_internal(
break;
case BUS_MATCH_MESSAGE_TYPE:
+ if (c->value_u8 != SD_BUS_MESSAGE_SIGNAL)
+ matches_name_change = false;
+
bloom_add_pair(bloom, "message-type", bus_message_type_to_string(c->value_u8));
using_bloom = true;
break;
case BUS_MATCH_INTERFACE:
+ if (!streq(c->value_str, "org.freedesktop.DBus"))
+ matches_name_change = false;
+
bloom_add_pair(bloom, "interface", c->value_str);
using_bloom = true;
break;
case BUS_MATCH_MEMBER:
+ if (!streq(c->value_str, "NameOwnerChanged"))
+ matches_name_change = false;
+
bloom_add_pair(bloom, "member", c->value_str);
using_bloom = true;
break;
case BUS_MATCH_PATH:
+ if (!streq(c->value_str, "/org/freedesktop/DBus"))
+ matches_name_change = false;
+
bloom_add_pair(bloom, "path", c->value_str);
using_bloom = true;
break;
@@ -491,6 +685,9 @@ int bus_add_match_internal(
case BUS_MATCH_ARG...BUS_MATCH_ARG_LAST: {
char buf[sizeof("arg")-1 + 2 + 1];
+ if (c->type - BUS_MATCH_ARG < 3)
+ name_change_arg[c->type - BUS_MATCH_ARG] = c->value_str;
+
snprintf(buf, sizeof(buf), "arg%u", c->type - BUS_MATCH_ARG);
bloom_add_pair(bloom, buf, c->value_str);
using_bloom = true;
@@ -560,7 +757,20 @@ int bus_add_match_internal(
if (r < 0)
return -errno;
- } else {
+ if (matches_name_change) {
+
+ /* If this match could theoretically match
+ * NameOwnerChanged messages, we need to
+ * install a second non-bloom filter explitly
+ * for it */
+
+ r = add_name_change_match(bus, cookie, name_change_arg[0], name_change_arg[1], name_change_arg[2]);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+ } else
return sd_bus_call_method(
bus,
"org.freedesktop.DBus",
@@ -571,9 +781,6 @@ int bus_add_match_internal(
NULL,
"s",
match);
- }
-
- return 0;
}
int bus_remove_match_internal(
@@ -597,6 +804,8 @@ int bus_remove_match_internal(
if (r < 0)
return -errno;
+ return 0;
+
} else {
return sd_bus_call_method(
bus,
@@ -609,8 +818,6 @@ int bus_remove_match_internal(
"s",
match);
}
-
- return 0;
}
_public_ int sd_bus_get_owner_machine_id(sd_bus *bus, const char *name, sd_id128_t *machine) {
diff --git a/src/libsystemd-bus/bus-internal.h b/src/libsystemd-bus/bus-internal.h
index 9c9e142a5b..7a7d8f5ffb 100644
--- a/src/libsystemd-bus/bus-internal.h
+++ b/src/libsystemd-bus/bus-internal.h
@@ -294,6 +294,8 @@ int bus_ensure_running(sd_bus *bus);
int bus_start_running(sd_bus *bus);
int bus_next_address(sd_bus *bus);
+int bus_seal_message(sd_bus *b, sd_bus_message *m);
+
bool bus_pid_changed(sd_bus *bus);
char *bus_address_escape(const char *v);
diff --git a/src/libsystemd-bus/bus-kernel.c b/src/libsystemd-bus/bus-kernel.c
index 6962fdcdb3..1b586d81d0 100644
--- a/src/libsystemd-bus/bus-kernel.c
+++ b/src/libsystemd-bus/bus-kernel.c
@@ -33,6 +33,9 @@
#include "bus-message.h"
#include "bus-kernel.h"
#include "bus-bloom.h"
+#include "bus-util.h"
+
+#define UNIQUE_NAME_MAX (3+DECIMAL_STR_MAX(uint64_t))
int bus_kernel_parse_unique_name(const char *s, uint64_t *id) {
int r;
@@ -422,6 +425,147 @@ static void close_kdbus_msg(sd_bus *bus, struct kdbus_msg *k) {
}
}
+static int return_name_owner_changed(sd_bus *bus, const char *name, const char *old_owner, const char *new_owner, sd_bus_message **ret) {
+ _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+ int r;
+
+ assert(bus);
+ assert(ret);
+
+ 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;
+
+ *ret = m;
+ m = NULL;
+
+ return 1;
+}
+
+static int translate_name_change(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item *d, sd_bus_message **ret) {
+ char new_owner[UNIQUE_NAME_MAX], old_owner[UNIQUE_NAME_MAX];
+
+ assert(bus);
+ assert(k);
+ assert(d);
+ assert(ret);
+
+ 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 return_name_owner_changed(bus, d->name_change.name, old_owner, new_owner, ret);
+}
+
+static int translate_id_change(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item *d, sd_bus_message **ret) {
+ char owner[UNIQUE_NAME_MAX];
+
+ assert(bus);
+ assert(k);
+ assert(d);
+ assert(ret);
+
+ sprintf(owner, ":1.%llu", d->id_change.id);
+
+ return return_name_owner_changed(
+ bus, owner,
+ d->type == KDBUS_ITEM_ID_ADD ? NULL : owner,
+ d->type == KDBUS_ITEM_ID_ADD ? owner : NULL,
+ ret);
+}
+
+static int translate_reply(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item *d, sd_bus_message **ret) {
+ _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+ int r;
+
+ assert(bus);
+ assert(k);
+ assert(d);
+ assert(ret);
+
+ 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;
+
+ *ret = m;
+ m = NULL;
+
+ return 1;
+}
+
+static int bus_kernel_translate_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_message **ret) {
+ struct kdbus_item *d, *found = NULL;
+
+ static int (* const translate[])(sd_bus *bus, struct kdbus_msg *k, struct kdbus_item *d, sd_bus_message **ret) = {
+ [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(ret);
+ 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, ret);
+}
+
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;
@@ -435,17 +579,16 @@ 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_PART_FOREACH(d, k, items) {
size_t l;
l = d->size - offsetof(struct kdbus_item, data);
- if (d->type == KDBUS_ITEM_PAYLOAD_OFF) {
+ switch (d->type) {
+ case KDBUS_ITEM_PAYLOAD_OFF:
if (!h) {
h = (struct bus_header *)((uint8_t *)bus->kdbus_buffer + d->vec.offset);
@@ -454,15 +597,16 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_mess
}
n_bytes += d->vec.size;
+ break;
- } else if (d->type == KDBUS_ITEM_PAYLOAD_MEMFD) {
-
+ case KDBUS_ITEM_PAYLOAD_MEMFD:
if (!h)
return -EBADMSG;
n_bytes += d->memfd.size;
+ break;
- } else if (d->type == KDBUS_ITEM_FDS) {
+ case KDBUS_ITEM_FDS: {
int *f;
unsigned j;
@@ -474,9 +618,13 @@ 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_ITEM_SECLABEL)
+ case KDBUS_ITEM_SECLABEL:
seclabel = d->str;
+ break;
+ }
}
if (!h)
@@ -498,7 +646,9 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_mess
l = d->size - offsetof(struct kdbus_item, data);
- if (d->type == KDBUS_ITEM_PAYLOAD_OFF) {
+ switch (d->type) {
+
+ case KDBUS_ITEM_PAYLOAD_OFF: {
size_t begin_body;
begin_body = BUS_MESSAGE_BODY_BEGIN(m);
@@ -531,7 +681,10 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_mess
}
idx += d->vec.size;
- } else if (d->type == KDBUS_ITEM_PAYLOAD_MEMFD) {
+ break;
+ }
+
+ case KDBUS_ITEM_PAYLOAD_MEMFD: {
struct bus_body_part *part;
if (idx < BUS_MESSAGE_BODY_BEGIN(m)) {
@@ -550,56 +703,73 @@ static int bus_kernel_make_message(sd_bus *bus, struct kdbus_msg *k, sd_bus_mess
part->sealed = true;
idx += d->memfd.size;
+ break;
+ }
- } else if (d->type == KDBUS_ITEM_CREDS) {
+ 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;
- } else if (d->type == KDBUS_ITEM_TIMESTAMP) {
+ case KDBUS_ITEM_TIMESTAMP:
m->realtime = d->timestamp.realtime_ns / NSEC_PER_USEC;
m->monotonic = d->timestamp.monotonic_ns / NSEC_PER_USEC;
+ break;
- } else if (d->type == KDBUS_ITEM_PID_COMM) {
+ case KDBUS_ITEM_PID_COMM:
m->creds.comm = d->str;
m->creds.mask |= SD_BUS_CREDS_COMM & bus->creds_mask;
+ break;
- } else if (d->type == KDBUS_ITEM_TID_COMM) {
+ case KDBUS_ITEM_TID_COMM:
m->creds.tid_comm = d->str;
m->creds.mask |= SD_BUS_CREDS_TID_COMM & bus->creds_mask;
+ break;
- } else if (d->type == KDBUS_ITEM_EXE) {
+ case KDBUS_ITEM_EXE:
m->creds.exe = d->str;
m->creds.mask |= SD_BUS_CREDS_EXE & bus->creds_mask;
+ break;
- } else if (d->type == KDBUS_ITEM_CMDLINE) {
+ 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;
- } else if (d->type == KDBUS_ITEM_CGROUP) {
+ 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;
- } else if (d->type == KDBUS_ITEM_AUDIT) {
+ 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;
- } else if (d->type == KDBUS_ITEM_CAPS) {
+ 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;
- } else if (d->type == KDBUS_ITEM_DST_NAME)
+ case KDBUS_ITEM_DST_NAME:
destination = d->str;
- else if (d->type != KDBUS_ITEM_FDS &&
- d->type != KDBUS_ITEM_SECLABEL &&
- d->type != KDBUS_ITEM_NAMES)
+ 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);
@@ -666,7 +836,13 @@ int bus_kernel_read_message(sd_bus *bus, sd_bus_message **m) {
}
k = (struct kdbus_msg *)((uint8_t *)bus->kdbus_buffer + off);
- r = bus_kernel_make_message(bus, k, m);
+ if (k->payload_type == KDBUS_PAYLOAD_DBUS1)
+ r = bus_kernel_make_message(bus, k, m);
+ else if (k->payload_type == KDBUS_PAYLOAD_KERNEL)
+ r = bus_kernel_translate_message(bus, k, m);
+ else
+ r = 0;
+
if (r <= 0)
close_kdbus_msg(bus, k);
diff --git a/src/libsystemd-bus/sd-bus.c b/src/libsystemd-bus/sd-bus.c
index 2fe6340e36..01176b010e 100644
--- a/src/libsystemd-bus/sd-bus.c
+++ b/src/libsystemd-bus/sd-bus.c
@@ -1257,7 +1257,7 @@ _public_ int sd_bus_get_server_id(sd_bus *bus, sd_id128_t *server_id) {
return 0;
}
-static int bus_seal_message(sd_bus *b, sd_bus_message *m) {
+int bus_seal_message(sd_bus *b, sd_bus_message *m) {
assert(m);
if (m->header->version > b->message_version)