diff mbox series

[nft,2/5] cache: Filter rule list on kernel side

Message ID 20211201150258.18436-3-phil@nwl.cc
State Changes Requested
Delegated to: Pablo Neira
Headers show
Series Reduce cache overhead a bit | expand

Commit Message

Phil Sutter Dec. 1, 2021, 3:02 p.m. UTC
Instead of fetching all existing rules in kernel's ruleset and filtering
in user space, add payload to the dump request specifying the table and
chain to filter for.

Since list_rule_cb() no longer needs the filter, pass only netlink_ctx
to the callback and drop struct rule_cache_dump_ctx.

Signed-off-by: Phil Sutter <phil@nwl.cc>
---
 include/mnl.h |  4 ++--
 src/cache.c   | 23 +++--------------------
 src/mnl.c     | 21 +++++++++++++++++++--
 3 files changed, 24 insertions(+), 24 deletions(-)
diff mbox series

Patch

diff --git a/include/mnl.h b/include/mnl.h
index 344030f306940..19faa651fdb91 100644
--- a/include/mnl.h
+++ b/include/mnl.h
@@ -33,8 +33,8 @@  int mnl_nft_rule_add(struct netlink_ctx *ctx, struct cmd *cmd,
 int mnl_nft_rule_del(struct netlink_ctx *ctx, struct cmd *cmd);
 int mnl_nft_rule_replace(struct netlink_ctx *ctx, struct cmd *cmd);
 
-struct nftnl_rule_list *mnl_nft_rule_dump(struct netlink_ctx *ctx,
-					  int family);
+struct nftnl_rule_list *mnl_nft_rule_dump(struct netlink_ctx *ctx, int family,
+					  const struct nft_cache_filter *filter);
 
 int mnl_nft_chain_add(struct netlink_ctx *ctx, struct cmd *cmd,
 		      unsigned int flags);
diff --git a/src/cache.c b/src/cache.c
index 66da2b3475732..484efdb93862b 100644
--- a/src/cache.c
+++ b/src/cache.c
@@ -441,16 +441,9 @@  struct chain *chain_cache_find(const struct table *table, const char *name)
 	return NULL;
 }
 
-struct rule_cache_dump_ctx {
-	struct netlink_ctx	*nlctx;
-	const struct nft_cache_filter *filter;
-};
-
 static int list_rule_cb(struct nftnl_rule *nlr, void *data)
 {
-	struct rule_cache_dump_ctx *rule_ctx = data;
-	const struct nft_cache_filter *filter = rule_ctx->filter;
-	struct netlink_ctx *ctx = rule_ctx->nlctx;
+	struct netlink_ctx *ctx = data;
 	const struct handle *h = ctx->data;
 	const char *table, *chain;
 	struct rule *rule;
@@ -465,12 +458,6 @@  static int list_rule_cb(struct nftnl_rule *nlr, void *data)
 	    (h->chain.name && strcmp(chain, h->chain.name) != 0))
 		return 0;
 
-	if (filter && filter->list.table && filter->list.chain &&
-	    (filter->list.family != family ||
-	     strcmp(filter->list.table, table) ||
-	     strcmp(filter->list.chain, chain)))
-		return 0;
-
 	netlink_dump_rule(nlr, ctx);
 	rule = netlink_delinearize_rule(ctx, nlr);
 	list_add_tail(&rule->list, &ctx->list);
@@ -481,13 +468,9 @@  static int list_rule_cb(struct nftnl_rule *nlr, void *data)
 static int rule_cache_init(struct netlink_ctx *ctx, const struct handle *h,
 			   const struct nft_cache_filter *filter)
 {
-	struct rule_cache_dump_ctx rule_ctx = {
-		.nlctx = ctx,
-		.filter = filter,
-	};
 	struct nftnl_rule_list *rule_cache;
 
-	rule_cache = mnl_nft_rule_dump(ctx, h->family);
+	rule_cache = mnl_nft_rule_dump(ctx, h->family, filter);
 	if (rule_cache == NULL) {
 		if (errno == EINTR)
 			return -1;
@@ -496,7 +479,7 @@  static int rule_cache_init(struct netlink_ctx *ctx, const struct handle *h,
 	}
 
 	ctx->data = h;
-	nftnl_rule_list_foreach(rule_cache, list_rule_cb, &rule_ctx);
+	nftnl_rule_list_foreach(rule_cache, list_rule_cb, ctx);
 	nftnl_rule_list_free(rule_cache);
 	return 0;
 }
diff --git a/src/mnl.c b/src/mnl.c
index edd951186d3a7..35fff92a180c7 100644
--- a/src/mnl.c
+++ b/src/mnl.c
@@ -653,20 +653,37 @@  err_free:
 	return MNL_CB_OK;
 }
 
-struct nftnl_rule_list *mnl_nft_rule_dump(struct netlink_ctx *ctx,
-					  int family)
+struct nftnl_rule_list *mnl_nft_rule_dump(struct netlink_ctx *ctx, int family,
+					  const struct nft_cache_filter *filter)
 {
 	char buf[MNL_SOCKET_BUFFER_SIZE];
 	struct nftnl_rule_list *nlr_list;
+	struct nftnl_rule *nlr = NULL;
 	struct nlmsghdr *nlh;
 	int ret;
 
+	if (filter && filter->list.table) {
+		nlr = nftnl_rule_alloc();
+		if (!nlr)
+			memory_allocation_error();
+
+		nftnl_rule_set_str(nlr, NFTNL_RULE_TABLE,
+				   filter->list.table);
+		if (filter->list.chain)
+			nftnl_rule_set_str(nlr, NFTNL_RULE_CHAIN,
+					   filter->list.chain);
+	}
+
 	nlr_list = nftnl_rule_list_alloc();
 	if (nlr_list == NULL)
 		memory_allocation_error();
 
 	nlh = nftnl_nlmsg_build_hdr(buf, NFT_MSG_GETRULE, family,
 				    NLM_F_DUMP, ctx->seqnum);
+	if (nlr) {
+		nftnl_rule_nlmsg_build_payload(nlh, nlr);
+		nftnl_rule_free(nlr);
+	}
 
 	ret = nft_mnl_talk(ctx, nlh, nlh->nlmsg_len, rule_cb, nlr_list);
 	if (ret < 0)