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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /tools/testing/selftests/bpf/progs/sendmsg4_prog.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/bpf/progs/sendmsg4_prog.c')
-rw-r--r--tools/testing/selftests/bpf/progs/sendmsg4_prog.c54
1 files changed, 54 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/sendmsg4_prog.c b/tools/testing/selftests/bpf/progs/sendmsg4_prog.c
new file mode 100644
index 000000000..ea75a44cb
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/sendmsg4_prog.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018 Facebook
+
+#include <linux/stddef.h>
+#include <linux/bpf.h>
+#include <sys/socket.h>
+
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_endian.h>
+
+#include <bpf_sockopt_helpers.h>
+
+#define SRC1_IP4 0xAC100001U /* 172.16.0.1 */
+#define SRC2_IP4 0x00000000U
+#define SRC_REWRITE_IP4 0x7f000004U
+#define DST_IP4 0xC0A801FEU /* 192.168.1.254 */
+#define DST_REWRITE_IP4 0x7f000001U
+#define DST_PORT 4040
+#define DST_REWRITE_PORT4 4444
+
+SEC("cgroup/sendmsg4")
+int sendmsg_v4_prog(struct bpf_sock_addr *ctx)
+{
+ int prio;
+
+ if (ctx->type != SOCK_DGRAM)
+ return 0;
+
+ if (!get_set_sk_priority(ctx))
+ return 0;
+
+ /* Rewrite source. */
+ if (ctx->msg_src_ip4 == bpf_htonl(SRC1_IP4) ||
+ ctx->msg_src_ip4 == bpf_htonl(SRC2_IP4)) {
+ ctx->msg_src_ip4 = bpf_htonl(SRC_REWRITE_IP4);
+ } else {
+ /* Unexpected source. Reject sendmsg. */
+ return 0;
+ }
+
+ /* Rewrite destination. */
+ if ((ctx->user_ip4 >> 24) == (bpf_htonl(DST_IP4) >> 24) &&
+ ctx->user_port == bpf_htons(DST_PORT)) {
+ ctx->user_ip4 = bpf_htonl(DST_REWRITE_IP4);
+ ctx->user_port = bpf_htons(DST_REWRITE_PORT4);
+ } else {
+ /* Unexpected source. Reject sendmsg. */
+ return 0;
+ }
+
+ return 1;
+}
+
+char _license[] SEC("license") = "GPL";