* [PATCH nft 1/2] examples: add libnftables example program
2022-02-14 12:16 [PATCH nft 0/2] add example folder Pablo Neira Ayuso
@ 2022-02-14 12:16 ` Pablo Neira Ayuso
2022-02-14 12:16 ` [PATCH nft 2/2] examples: load ruleset from JSON Pablo Neira Ayuso
1 sibling, 0 replies; 3+ messages in thread
From: Pablo Neira Ayuso @ 2022-02-14 12:16 UTC (permalink / raw)
To: netfilter-devel
Create an example folder to add example source code files to show how to
use libnftables. Add first example program using the buffer API.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
configure.ac | 1 +
examples/Makefile.am | 3 +++
examples/nft-buffer.c | 34 ++++++++++++++++++++++++++++++++++
3 files changed, 38 insertions(+)
create mode 100644 examples/Makefile.am
create mode 100644 examples/nft-buffer.c
diff --git a/configure.ac b/configure.ac
index 503883f28c66..d321c960562b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -145,6 +145,7 @@ AC_CONFIG_FILES([ \
files/osf/Makefile \
doc/Makefile \
py/Makefile \
+ examples/Makefile \
])
AC_OUTPUT
diff --git a/examples/Makefile.am b/examples/Makefile.am
new file mode 100644
index 000000000000..dd637fe31340
--- /dev/null
+++ b/examples/Makefile.am
@@ -0,0 +1,3 @@
+noinst_PROGRAMS = nft-buffer
+
+LDADD = $(top_builddir)/src/libnftables.la
diff --git a/examples/nft-buffer.c b/examples/nft-buffer.c
new file mode 100644
index 000000000000..1c4b1e041d75
--- /dev/null
+++ b/examples/nft-buffer.c
@@ -0,0 +1,34 @@
+/* gcc nft-buffer.c -o nft-buffer -lnftables */
+#include <stdlib.h>
+#include <nftables/libnftables.h>
+
+const char ruleset[] =
+ "flush ruleset;"
+ "add table x;"
+ "add chain x y { type filter hook input priority 0; };"
+ "add rule x y counter;";
+
+int main(void)
+{
+ struct nft_ctx *ctx;
+ int err;
+
+ ctx = nft_ctx_new(0);
+ if (!ctx) {
+ perror("cannot allocate nft context");
+ return EXIT_FAILURE;
+ }
+
+ /* create ruleset: all commands in the buffer are atomically applied */
+ err = nft_run_cmd_from_buffer(ctx, ruleset);
+ if (err < 0)
+ fprintf(stderr, "failed to run nftables command\n");
+
+ err = nft_run_cmd_from_buffer(ctx, "list ruleset");
+ if (err < 0)
+ fprintf(stderr, "failed to run nftables command\n");
+
+ nft_ctx_free(ctx);
+
+ return EXIT_SUCCESS;
+}
--
2.30.2
^ permalink raw reply related [flat|nested] 3+ messages in thread* [PATCH nft 2/2] examples: load ruleset from JSON
2022-02-14 12:16 [PATCH nft 0/2] add example folder Pablo Neira Ayuso
2022-02-14 12:16 ` [PATCH nft 1/2] examples: add libnftables example program Pablo Neira Ayuso
@ 2022-02-14 12:16 ` Pablo Neira Ayuso
1 sibling, 0 replies; 3+ messages in thread
From: Pablo Neira Ayuso @ 2022-02-14 12:16 UTC (permalink / raw)
To: netfilter-devel
Add an example to load a ruleset file expressed in JSON.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
examples/Makefile.am | 3 ++-
examples/json-ruleset.nft | 43 +++++++++++++++++++++++++++++++++++++++
examples/nft-json-file.c | 30 +++++++++++++++++++++++++++
3 files changed, 75 insertions(+), 1 deletion(-)
create mode 100644 examples/json-ruleset.nft
create mode 100644 examples/nft-json-file.c
diff --git a/examples/Makefile.am b/examples/Makefile.am
index dd637fe31340..c972170d3fdc 100644
--- a/examples/Makefile.am
+++ b/examples/Makefile.am
@@ -1,3 +1,4 @@
-noinst_PROGRAMS = nft-buffer
+noinst_PROGRAMS = nft-buffer \
+ nft-json-file
LDADD = $(top_builddir)/src/libnftables.la
diff --git a/examples/json-ruleset.nft b/examples/json-ruleset.nft
new file mode 100644
index 000000000000..acea1786649a
--- /dev/null
+++ b/examples/json-ruleset.nft
@@ -0,0 +1,43 @@
+{
+ "nftables": [
+ {
+ "flush": {
+ "ruleset": {
+ "family": "ip"
+ }
+ }
+ },
+ {
+ "table": {
+ "family": "ip",
+ "name": "x"
+ }
+ },
+ {
+ "chain": {
+ "family": "ip",
+ "table": "x",
+ "name": "y",
+ "type": "filter",
+ "hook": "input",
+ "prio": 0,
+ "policy": "accept"
+ }
+ },
+ {
+ "rule": {
+ "family": "ip",
+ "table": "x",
+ "chain": "y",
+ "expr": [
+ {
+ "counter": {
+ "packets": 0,
+ "bytes": 0
+ }
+ }
+ ]
+ }
+ }
+ ]
+}
diff --git a/examples/nft-json-file.c b/examples/nft-json-file.c
new file mode 100644
index 000000000000..0c832f22e206
--- /dev/null
+++ b/examples/nft-json-file.c
@@ -0,0 +1,30 @@
+/* gcc nft-json-file.c -o nft-json-file -lnftables */
+#include <stdlib.h>
+#include <nftables/libnftables.h>
+
+int main(void)
+{
+ struct nft_ctx *ctx;
+ int err;
+
+ ctx = nft_ctx_new(0);
+ if (!ctx) {
+ perror("cannot allocate nft context");
+ return EXIT_FAILURE;
+ }
+
+ nft_ctx_output_set_flags(ctx, NFT_CTX_OUTPUT_JSON);
+
+ /* create ruleset: all commands in the buffer are atomically applied */
+ err = nft_run_cmd_from_filename(ctx, "json-ruleset.nft");
+ if (err < 0)
+ fprintf(stderr, "failed to run nftables command\n");
+
+ err = nft_run_cmd_from_buffer(ctx, "list ruleset");
+ if (err < 0)
+ fprintf(stderr, "failed to run nftables command\n");
+
+ nft_ctx_free(ctx);
+
+ return EXIT_SUCCESS;
+}
--
2.30.2
^ permalink raw reply related [flat|nested] 3+ messages in thread