bus: align kdbus ioctl parameters to 8byte

[elogind.git] / src / libsystemd / sd-bus / bus-kernel.c

diff --git a/src/libsystemd/sd-bus/bus-kernel.c b/src/libsystemd/sd-bus/bus-kernel.c
index ca0eddb38d561ab4dcc5ad97ad6683b73be65227..c30491e687d93df414c4b0c5e98d3d1674b30289 100644 (file)
--- a/src/libsystemd/sd-bus/bus-kernel.c
+++ b/src/libsystemd/sd-bus/bus-kernel.c
@@ -25,6 +25,7 @@
 
 #include <fcntl.h>
 #include <malloc.h>
+#include <libgen.h>
 #include <sys/mman.h>
 #include <sys/prctl.h>
 
@@ -708,7 +709,7 @@ int bus_kernel_take_fd(sd_bus *b) {
                 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;
@@ -795,7 +796,7 @@ int bus_kernel_connect(sd_bus *b) {
 }
 
 static void close_kdbus_msg(sd_bus *bus, struct kdbus_msg *k) {
-        uint64_t off;
+        uint64_t off _alignas_(8);
         struct kdbus_item *d;
 
         assert(bus);
@@ -1267,10 +1268,11 @@ int bus_kernel_create_bus(const char *name, bool world, char **s) {
         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));
+        make = alloca0_align(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),
+                             8);
 
         make->size = offsetof(struct kdbus_cmd_make, items);
 
@@ -1408,6 +1410,97 @@ int bus_kernel_open_bus_fd(const char *bus, char **path) {
         return fd;
 }
 
+int bus_kernel_create_endpoint(const char *bus_name, const char *ep_name, char **ep_path) {
+        _cleanup_free_ char *path;
+        struct kdbus_cmd_make *make;
+        struct kdbus_item *n;
+        size_t size;
+        int fd;
+
+        fd = bus_kernel_open_bus_fd(bus_name, &path);
+        if (fd < 0)
+                return fd;
+
+        size = ALIGN8(offsetof(struct kdbus_cmd_make, items));
+        size += ALIGN8(offsetof(struct kdbus_item, str) + strlen(ep_name) + 1);
+
+        make = alloca0_align(size, 8);
+        make->size = size;
+        make->flags = KDBUS_MAKE_ACCESS_WORLD;
+
+        n = make->items;
+
+        n->type = KDBUS_ITEM_MAKE_NAME;
+        n->size = offsetof(struct kdbus_item, str) + strlen(ep_name) + 1;
+        strcpy(n->str, ep_name);
+
+        if (ioctl(fd, KDBUS_CMD_EP_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) {
+                safe_close(fd);
+                return -ENOTSUP;
+        }
+
+        if (ep_path) {
+                int r = asprintf(ep_path, "%s/%s", dirname(path), ep_name);
+                if (r == -1 || !*ep_path) {
+                        safe_close(fd);
+                        return -ENOMEM;
+                }
+        }
+
+        return fd;
+}
+
+int bus_kernel_set_endpoint_policy(int fd, uid_t uid, BusEndpoint *ep) {
+
+        struct kdbus_cmd_update *update;
+        struct kdbus_item *n;
+        BusEndpointPolicy *po;
+        Iterator i;
+        size_t size;
+        int r;
+
+        size = ALIGN8(offsetof(struct kdbus_cmd_update, items));
+
+        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_EP_UPDATE, update);
+        if (r < 0)
+                return -errno;
+
+        return 0;
+}
+
 int bus_kernel_make_starter(
                 int fd,
                 const char *name,
@@ -1436,7 +1529,7 @@ int bus_kernel_make_starter(
                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(size);
+        hello = alloca0_align(size, 8);
 
         n = hello->items;
         strcpy(n->str, name);
@@ -1496,9 +1589,10 @@ int bus_kernel_create_domain(const char *name, char **s) {
         if (fd < 0)
                 return -errno;
 
-        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) +
+                                    offsetof(struct kdbus_item, str) +
+                                    strlen(name) + 1),
+                             8);
 
         n = make->items;
         strcpy(n->str, name);