mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-28 11:18:45 +07:00
435f90a338
This patch provides a tcp_bpf based eBPF sample. The test - ncat(1) as the TCP client program to connect() to a port with the intention of triggerring SYN retransmissions: we first install an iptables DROP rule to make sure ncat SYNs are resent (instead of aborting instantly after a TCP RST) - has a bpf kernel module that sends a perf-event notification for each TCP retransmit, and also tracks the number of such notifications sent in the global_map The test passes when the number of event notifications intercepted in user-space matches the value in the global_map. Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
96 lines
2.0 KiB
C
96 lines
2.0 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <stddef.h>
|
|
#include <string.h>
|
|
#include <linux/bpf.h>
|
|
#include <linux/if_ether.h>
|
|
#include <linux/if_packet.h>
|
|
#include <linux/ip.h>
|
|
#include <linux/ipv6.h>
|
|
#include <linux/types.h>
|
|
#include <linux/socket.h>
|
|
#include <linux/tcp.h>
|
|
#include <netinet/in.h>
|
|
#include "bpf_helpers.h"
|
|
#include "bpf_endian.h"
|
|
#include "test_tcpnotify.h"
|
|
|
|
struct bpf_map_def SEC("maps") global_map = {
|
|
.type = BPF_MAP_TYPE_ARRAY,
|
|
.key_size = sizeof(__u32),
|
|
.value_size = sizeof(struct tcpnotify_globals),
|
|
.max_entries = 4,
|
|
};
|
|
|
|
struct bpf_map_def SEC("maps") perf_event_map = {
|
|
.type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
|
|
.key_size = sizeof(int),
|
|
.value_size = sizeof(__u32),
|
|
.max_entries = 2,
|
|
};
|
|
|
|
int _version SEC("version") = 1;
|
|
|
|
SEC("sockops")
|
|
int bpf_testcb(struct bpf_sock_ops *skops)
|
|
{
|
|
int rv = -1;
|
|
int op;
|
|
|
|
op = (int) skops->op;
|
|
|
|
if (bpf_ntohl(skops->remote_port) != TESTPORT) {
|
|
skops->reply = -1;
|
|
return 0;
|
|
}
|
|
|
|
switch (op) {
|
|
case BPF_SOCK_OPS_TIMEOUT_INIT:
|
|
case BPF_SOCK_OPS_RWND_INIT:
|
|
case BPF_SOCK_OPS_NEEDS_ECN:
|
|
case BPF_SOCK_OPS_BASE_RTT:
|
|
case BPF_SOCK_OPS_RTO_CB:
|
|
rv = 1;
|
|
break;
|
|
|
|
case BPF_SOCK_OPS_TCP_CONNECT_CB:
|
|
case BPF_SOCK_OPS_TCP_LISTEN_CB:
|
|
case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:
|
|
case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
|
|
bpf_sock_ops_cb_flags_set(skops, (BPF_SOCK_OPS_RETRANS_CB_FLAG|
|
|
BPF_SOCK_OPS_RTO_CB_FLAG));
|
|
rv = 1;
|
|
break;
|
|
case BPF_SOCK_OPS_RETRANS_CB: {
|
|
__u32 key = 0;
|
|
struct tcpnotify_globals g, *gp;
|
|
struct tcp_notifier msg = {
|
|
.type = 0xde,
|
|
.subtype = 0xad,
|
|
.source = 0xbe,
|
|
.hash = 0xef,
|
|
};
|
|
|
|
rv = 1;
|
|
|
|
/* Update results */
|
|
gp = bpf_map_lookup_elem(&global_map, &key);
|
|
if (!gp)
|
|
break;
|
|
g = *gp;
|
|
g.total_retrans = skops->total_retrans;
|
|
g.ncalls++;
|
|
bpf_map_update_elem(&global_map, &key, &g,
|
|
BPF_ANY);
|
|
bpf_perf_event_output(skops, &perf_event_map,
|
|
BPF_F_CURRENT_CPU,
|
|
&msg, sizeof(msg));
|
|
}
|
|
break;
|
|
default:
|
|
rv = -1;
|
|
}
|
|
skops->reply = rv;
|
|
return 1;
|
|
}
|
|
char _license[] SEC("license") = "GPL";
|