bus: rework bloom filter logic to operate with variable bloom filter

sizes and numbers of hash functions

In order to make the bloom filter logic more future proof communicate
bloom filter parameters from the original bus creator to the clients,
and allow them to be variable within certain ranges.

1 files changed, 13 insertions, 13 deletions

diff --git a/src/libsystemd/sd-bus/bus-control.c b/src/libsystemd/sd-bus/bus-control.c
index 35fd384cdf..846307d664 100644
--- a/src/libsystemd/sd-bus/bus-control.c
+++ b/src/libsystemd/sd-bus/bus-control.c
@@ -926,7 +926,7 @@ int bus_add_match_internal_kernel(
 
         struct kdbus_cmd_match *m;
         struct kdbus_item *item;
-        uint64_t bloom[BLOOM_SIZE/8];
+        uint64_t *bloom;
         size_t sz;
         const char *sender = NULL;
         size_t sender_length = 0;
@@ -939,7 +939,7 @@ int bus_add_match_internal_kernel(
 
         assert(bus);
 
-        zero(bloom);
+        bloom = alloca0(bus->bloom_size);
 
         sz = ALIGN8(offsetof(struct kdbus_cmd_match, items));
 
@@ -969,7 +969,7 @@ int bus_add_match_internal_kernel(
                         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));
+                        bloom_add_pair(bloom, bus->bloom_size, bus->bloom_n_hash, "message-type", bus_message_type_to_string(c->value_u8));
                         using_bloom = true;
                         break;
 
@@ -977,7 +977,7 @@ int bus_add_match_internal_kernel(
                         if (!streq(c->value_str, "org.freedesktop.DBus"))
                                 matches_name_change = false;
 
-                        bloom_add_pair(bloom, "interface", c->value_str);
+                        bloom_add_pair(bloom, bus->bloom_size, bus->bloom_n_hash, "interface", c->value_str);
                         using_bloom = true;
                         break;
 
@@ -985,7 +985,7 @@ int bus_add_match_internal_kernel(
                         if (!streq(c->value_str, "NameOwnerChanged"))
                                 matches_name_change = false;
 
-                        bloom_add_pair(bloom, "member", c->value_str);
+                        bloom_add_pair(bloom, bus->bloom_size, bus->bloom_n_hash, "member", c->value_str);
                         using_bloom = true;
                         break;
 
@@ -993,13 +993,13 @@ int bus_add_match_internal_kernel(
                         if (!streq(c->value_str, "/org/freedesktop/DBus"))
                                 matches_name_change = false;
 
-                        bloom_add_pair(bloom, "path", c->value_str);
+                        bloom_add_pair(bloom, bus->bloom_size, bus->bloom_n_hash, "path", c->value_str);
                         using_bloom = true;
                         break;
 
                 case BUS_MATCH_PATH_NAMESPACE:
                         if (!streq(c->value_str, "/")) {
-                                bloom_add_pair(bloom, "path-slash-prefix", c->value_str);
+                                bloom_add_pair(bloom, bus->bloom_size, bus->bloom_n_hash, "path-slash-prefix", c->value_str);
                                 using_bloom = true;
                         }
                         break;
@@ -1011,7 +1011,7 @@ int bus_add_match_internal_kernel(
                                 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);
+                        bloom_add_pair(bloom, bus->bloom_size, bus->bloom_n_hash, buf, c->value_str);
                         using_bloom = true;
                         break;
                 }
@@ -1020,7 +1020,7 @@ int bus_add_match_internal_kernel(
                         char buf[sizeof("arg")-1 + 2 + sizeof("-slash-prefix")];
 
                         snprintf(buf, sizeof(buf), "arg%u-slash-prefix", c->type - BUS_MATCH_ARG_PATH);
-                        bloom_add_pair(bloom, buf, c->value_str);
+                        bloom_add_pair(bloom, bus->bloom_size, bus->bloom_n_hash, buf, c->value_str);
                         using_bloom = true;
                         break;
                 }
@@ -1029,7 +1029,7 @@ int bus_add_match_internal_kernel(
                         char buf[sizeof("arg")-1 + 2 + sizeof("-dot-prefix")];
 
                         snprintf(buf, sizeof(buf), "arg%u-dot-prefix", c->type - BUS_MATCH_ARG_NAMESPACE);
-                        bloom_add_pair(bloom, buf, c->value_str);
+                        bloom_add_pair(bloom, bus->bloom_size, bus->bloom_n_hash, buf, c->value_str);
                         using_bloom = true;
                         break;
                 }
@@ -1052,7 +1052,7 @@ int bus_add_match_internal_kernel(
         }
 
         if (using_bloom)
-                sz += ALIGN8(offsetof(struct kdbus_item, data64) + BLOOM_SIZE);
+                sz += ALIGN8(offsetof(struct kdbus_item, data64) + bus->bloom_size);
 
         m = alloca0(sz);
         m->size = sz;
@@ -1069,9 +1069,9 @@ int bus_add_match_internal_kernel(
         }
 
         if (using_bloom) {
-                item->size = offsetof(struct kdbus_item, data64) + BLOOM_SIZE;
+                item->size = offsetof(struct kdbus_item, data64) + bus->bloom_size;
                 item->type = KDBUS_ITEM_BLOOM_MASK;
-                memcpy(item->data64, bloom, BLOOM_SIZE);
+                memcpy(item->data64, bloom, bus->bloom_size);
                 item = KDBUS_ITEM_NEXT(item);
         }