nfnetlink: allow specifying the socket buffer size

Allow the user to specify the socket buffer size and increase the default to 512KB. Signed-off-by: Jo-Philipp Wich <[email protected]>
jow- · Apr 10, 2020 · e757e06 · e757e06
1 parent 33c77cb
commit e757e06
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Showing 4 changed files with 20 additions and 4 deletions.
diff --git a/nfnetlink.c b/nfnetlink.c
@@ -340,7 +340,7 @@ handle_ack(struct nl_msg *msg, void *arg)
 
 
 int
-nfnetlink_connect(void)
+nfnetlink_connect(int bufsize)
 {
 	nl = nl_socket_alloc();
 
@@ -354,6 +354,9 @@ nfnetlink_connect(void)
 	                                  NFNLGRP_CONNTRACK_DESTROY, 0))
 		return -errno;
 
+	if (nl_socket_set_buffer_size(nl, bufsize, 0))
+		return -errno;
+
 	ufd.cb = handle_event;
 	ufd.fd = nl_socket_get_fd(nl);
 

diff --git a/nfnetlink.h b/nfnetlink.h
@@ -24,7 +24,7 @@
 #include "database.h"
 
 
-int nfnetlink_connect(void);
+int nfnetlink_connect(int bufsize);
 int nfnetlink_dump(bool allow_insert);
 
 #endif /* __NFNETLINK_H__ */
diff --git a/nlbwmon.c b/nlbwmon.c
@@ -59,6 +59,8 @@ struct options opt = {
 	.commit_interval = 86400,
 	.refresh_interval = 30,
 
+	.netlink_buffer_size = 524288,
+
 	.tempdir = "/tmp",
 	.socket = "/var/run/nlbwmon.sock",
 	.protocol_db = "/usr/share/nlbwmon/protocols",
@@ -203,8 +205,17 @@ server_main(int argc, char **argv)
 	int optchr, err;
 	char *e;
 
-	while ((optchr = getopt(argc, argv, "i:r:s:o:p:G:I:L:PZ")) > -1) {
+	while ((optchr = getopt(argc, argv, "b:i:r:s:o:p:G:I:L:PZ")) > -1) {
 		switch (optchr) {
+		case 'b':
+			opt.netlink_buffer_size = (int)strtol(optarg, &e, 0);
+			if (e == optarg || *e || opt.netlink_buffer_size < 32768) {
+				fprintf(stderr, "Invalid netlink buffer size '%s'\n",
+				        optarg);
+				return 1;
+			}
+			break;
+
 		case 'i':
 			err = parse_timearg(optarg, &opt.commit_interval);
 			if (err) {
@@ -321,7 +332,7 @@ server_main(int argc, char **argv)
 		exit(1);
 	}
 
-	err = nfnetlink_connect();
+	err = nfnetlink_connect(opt.netlink_buffer_size);
 
 	if (err) {
 		fprintf(stderr, "Unable to connect nfnetlink: %s\n",

diff --git a/nlbwmon.h b/nlbwmon.h
@@ -36,6 +36,8 @@ struct options {
 	time_t refresh_interval;
 	struct interval archive_interval;
 
+	int netlink_buffer_size;
+
 	const char *protocol_db;
 	const char *tempdir;
 	const char *socket;