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15#include <uapi/linux/bpf.h>
16#include <uapi/linux/if_ether.h>
17#include <uapi/linux/if_packet.h>
18#include <uapi/linux/ip.h>
19#include <linux/socket.h>
20#include <bpf/bpf_helpers.h>
21#include <bpf/bpf_endian.h>
22
23#define DEBUG 1
24
25SEC("sockops")
26int bpf_bufs(struct bpf_sock_ops *skops)
27{
28 int bufsize = 1500000;
29 int rwnd_init = 40;
30 int rv = 0;
31 int op;
32
33
34
35
36 if (bpf_ntohl(skops->remote_port) != 55601 &&
37 skops->local_port != 55601) {
38 skops->reply = -1;
39 return 1;
40 }
41
42 op = (int) skops->op;
43
44#ifdef DEBUG
45 bpf_printk("Returning %d\n", rv);
46#endif
47
48
49
50
51 switch (op) {
52 case BPF_SOCK_OPS_RWND_INIT:
53 rv = rwnd_init;
54 break;
55 case BPF_SOCK_OPS_TCP_CONNECT_CB:
56
57 rv = bpf_setsockopt(skops, SOL_SOCKET, SO_SNDBUF, &bufsize,
58 sizeof(bufsize));
59 rv += bpf_setsockopt(skops, SOL_SOCKET, SO_RCVBUF,
60 &bufsize, sizeof(bufsize));
61 break;
62 case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:
63
64 break;
65 case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
66
67 rv = bpf_setsockopt(skops, SOL_SOCKET, SO_SNDBUF, &bufsize,
68 sizeof(bufsize));
69 rv += bpf_setsockopt(skops, SOL_SOCKET, SO_RCVBUF,
70 &bufsize, sizeof(bufsize));
71 break;
72 default:
73 rv = -1;
74 }
75#ifdef DEBUG
76 bpf_printk("Returning %d\n", rv);
77#endif
78 skops->reply = rv;
79 return 1;
80}
81char _license[] SEC("license") = "GPL";
82