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-rw-r--r--samples/sockmap/sockmap_kern.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/samples/sockmap/sockmap_kern.c b/samples/sockmap/sockmap_kern.c
new file mode 100644
index 000000000000..6ff986f7059b
--- /dev/null
+++ b/samples/sockmap/sockmap_kern.c
@@ -0,0 +1,110 @@
+/* Copyright (c) 2017 Covalent IO, Inc. http://covalent.io
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#include <uapi/linux/bpf.h>
+#include <uapi/linux/if_ether.h>
+#include <uapi/linux/if_packet.h>
+#include <uapi/linux/ip.h>
+#include "../../tools/testing/selftests/bpf/bpf_helpers.h"
+#include "../../tools/testing/selftests/bpf/bpf_endian.h"
+
+/* Sockmap sample program connects a client and a backend together
+ * using cgroups.
+ *
+ * client:X <---> frontend:80 client:X <---> backend:80
+ *
+ * For simplicity we hard code values here and bind 1:1. The hard
+ * coded values are part of the setup in sockmap.sh script that
+ * is associated with this BPF program.
+ *
+ * The bpf_printk is verbose and prints information as connections
+ * are established and verdicts are decided.
+ */
+
+#define bpf_printk(fmt, ...) \
+({ \
+ char ____fmt[] = fmt; \
+ bpf_trace_printk(____fmt, sizeof(____fmt), \
+ ##__VA_ARGS__); \
+})
+
+struct bpf_map_def SEC("maps") sock_map = {
+ .type = BPF_MAP_TYPE_SOCKMAP,
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+ .max_entries = 20,
+};
+
+SEC("sk_skb1")
+int bpf_prog1(struct __sk_buff *skb)
+{
+ return skb->len;
+}
+
+SEC("sk_skb2")
+int bpf_prog2(struct __sk_buff *skb)
+{
+ __u32 lport = skb->local_port;
+ __u32 rport = skb->remote_port;
+ int ret = 0;
+
+ if (lport == 10000)
+ ret = 10;
+ else
+ ret = 1;
+
+ bpf_printk("sockmap: %d -> %d @ %d\n", lport, bpf_ntohl(rport), ret);
+ return bpf_sk_redirect_map(&sock_map, ret, 0);
+}
+
+SEC("sockops")
+int bpf_sockmap(struct bpf_sock_ops *skops)
+{
+ __u32 lport, rport;
+ int op, err = 0, index, key, ret;
+
+
+ op = (int) skops->op;
+
+ switch (op) {
+ case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
+ lport = skops->local_port;
+ rport = skops->remote_port;
+
+ if (lport == 10000) {
+ ret = 1;
+ err = bpf_sock_map_update(skops, &sock_map, &ret,
+ BPF_NOEXIST,
+ BPF_SOCKMAP_STRPARSER);
+ bpf_printk("passive(%i -> %i) map ctx update err: %d\n",
+ lport, bpf_ntohl(rport), err);
+ }
+ break;
+ case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:
+ lport = skops->local_port;
+ rport = skops->remote_port;
+
+ if (bpf_ntohl(rport) == 10001) {
+ ret = 10;
+ err = bpf_sock_map_update(skops, &sock_map, &ret,
+ BPF_NOEXIST,
+ BPF_SOCKMAP_STRPARSER);
+ bpf_printk("active(%i -> %i) map ctx update err: %d\n",
+ lport, bpf_ntohl(rport), err);
+ }
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+char _license[] SEC("license") = "GPL";