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No commits in common. "main" and "castip" have entirely different histories.
3
.gitignore
vendored
3
.gitignore
vendored
@ -1,3 +0,0 @@
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load_bpf
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tp_tcp.o
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.**.swp
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@ -5,12 +5,6 @@ This project collect some metrics for TCP. For doing that, I use eBPF.
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For executing and loading the eBPF program and to send data to InfluxDB, you need to install some packages:
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```
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sudo apt install linux-headers-`uname -r` clang-11 gcc gcc-multilib libbpf-dev libbpfcc bpfcc-tools
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```
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For installing bpftool command:
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```
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sudo apt install linux-tools-common linux-tools-generic
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```
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## Compile eBPF program
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3
Server/Dockerfile
Normal file
3
Server/Dockerfile
Normal file
@ -0,0 +1,3 @@
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FROM ubuntu:latest
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RUN apt-get update -y && apt-get install -y nmap
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14
exec.sh
14
exec.sh
@ -1,15 +1,5 @@
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#!/usr/bin/sh
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use_influxdb=true
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influxdb_host="<ip>"
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influxdb_orgid="<org ID>"
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influxdb_token="<token>"
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influxdb_bucket="tcp_metrics"
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clang-11 -g -O2 -target bpf -c tp_tcp.c -o tp_tcp.o && \
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gcc ic.c load_bpf.c -o load_bpf -lbpf && \
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if [ "$use_influxdb" = true ]; then
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sudo ./load_bpf $influxdb_host $influxdb_orgid $influxdb_token $influxdb_bucket
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else
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sudo ./load_bpf --no-influxdb
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fi
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gcc load_bpf.c -o load_bpf -lbpf && \
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sudo ./load_bpf
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42
ic.c
42
ic.c
@ -41,8 +41,6 @@ long influx_port = 0;
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char influx_database[256+1]; /* the influxdb database */
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char influx_username[64+1]; /* optional for influxdb access */
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char influx_password[64+1]; /* optional for influxdb access */
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char influx_token[128+1];
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char influx_orgID[64+1];
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char *output; /* all the stats must fit in this buffer */
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long output_size = 0;
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@ -119,14 +117,6 @@ void ic_influx_database(char *host, long port, char *db) /* note: converts influ
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}
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}
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void ic_influx_token(char *token){
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DEBUG fprintf(stderr, "ic_influx_token(token=%s))\n", token);
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strncpy(influx_token, token, 128);
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}
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void ic_influx_orgID(char *orgID){
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DEBUG fprintf(stderr, "ic_influx_orgID(ordID=%s))\n", orgID);
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strncpy(influx_orgID, orgID, 64);
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}
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void ic_influx_userpw(char *user, char *pw)
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{
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DEBUG fprintf(stderr,"ic_influx_userpw(username=%s,pssword=%s))\n",user,pw);
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@ -288,8 +278,9 @@ void ic_push()
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if (influx_port) {
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DEBUG fprintf(stderr, "ic_push() size=%ld\n", output_char);
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if (create_socket() == 1) {
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sprintf(buffer, "POST /api/v2/write?bucket=%s&orgID=%s HTTP/1.1\r\nHost: %s:%ld\r\nContent-Length: %ld\r\nAuthorization: Token %s\r\n\r\n",
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influx_database, influx_orgID, influx_hostname, influx_port, output_char, influx_token);
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sprintf(buffer, "POST /write?db=%s&u=%s&p=%s HTTP/1.1\r\nHost: %s:%ld\r\nContent-Length: %ld\r\n\r\n",
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influx_database, influx_username, influx_password, influx_hostname, influx_port, output_char);
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DEBUG fprintf(stderr, "buffer size=%ld\nbuffer=<%s>\n", strlen(buffer), buffer);
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if ((ret = write(sockfd, buffer, strlen(buffer))) != strlen(buffer)) {
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fprintf(stderr, "warning: \"write post to sockfd failed.\" errno=%d\n", errno);
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@ -332,30 +323,3 @@ void ic_push()
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output[0] = 0;
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output_char = 0;
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}
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int ic_read(const char *ipsrc, const char *ipdst){
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int value;
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int ret;
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char buffer[1024 * 8];
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char request[1024];
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char result[1024];
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int len = 0;
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sprintf(request, "from(bucket: \"tcp_metrics\")|> range(start: -1m)|> filter(fn: (r) => r[\"_measurement\"] == \"tcp_reset\")|> filter(fn: (r) => r[\"host\"] == \"%s\")|> filter(fn: (r) => r[\"_field\"] == \"%s\")|> last()", ipsrc, ipdst);
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len = strlen(request);
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if (create_socket() == 1) {
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sprintf(buffer, "POST /api/v2/query?bucket=%s&orgID=%s HTTP/1.1\r\nHost: %s:%ld\r\nContent-Type: application/vnd.flux\r\nAccept: application/csv\r\nContent-Length: %d\r\nAuthorization: Token %s\r\n\r\n%s",
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influx_database, influx_orgID, influx_hostname, influx_port, len, influx_token, request);
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DEBUG fprintf(stderr, "buffer size=%ld\nbuffer=<%s>\n", strlen(buffer), buffer);
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printf("%s\n", buffer);
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if ((ret = write(sockfd, buffer, strlen(buffer))) != strlen(buffer)) {
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fprintf(stderr, "warning: \"write post to sockfd failed.\" errno=%d\n", errno);
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}
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if ((ret = read(sockfd, result, sizeof(result))) > 0) {
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printf("%s\n", result);
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}
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close(sockfd);
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sockfd = 0;
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}
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return value;
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}
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3
ic.h
3
ic.h
@ -5,8 +5,6 @@
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*/
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void ic_influx_database(char *host, long port, char *db);
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void ic_influx_userpw(char *user, char *pw);
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void ic_influx_orgID(char *orgID);
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void ic_influx_token(char *token);
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void ic_tags(char *tags);
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void ic_measure(char *section);
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@ -20,6 +18,5 @@
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void ic_string(char *name, char *value);
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void ic_push();
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int ic_read(const char *, const char *);
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void ic_debug(int level);
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24
influxdb.py
Normal file
24
influxdb.py
Normal file
@ -0,0 +1,24 @@
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import influxdb_client
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from influxdb_client import InfluxDBClient, Point, WritePrecision
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from influxdb_client.client.write_api import SYNCHRONOUS
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import os
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#token = os.environ.get("dQV0BbJvy7W9Bool6FGh1ryb_uXBNqZB8BlJqb8yC4yNB8RTDSooT5hixoqMf8cBeXUXTRUdmkwlxnkI9PCsBA==")
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token = os.environ.get("sySU58aCfMdTGtBTttduzSS_x_4CBI1twpicYw4Idq9abZWGsAXdbvww2wWmwmLDTtrALAx4Q0wZK9PUIr4ejg==")
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org = "gbucchino"
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url = "http://192.168.1.68:8086"
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write_client = influxdb_client.InfluxDBClient(url=url, token=token, org=org)
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bucket="tcp"
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write_api = write_client.write_api(write_options=SYNCHRONOUS)
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for value in range(5):
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point = (
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Point("measurement1")
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.tag("tagname1", "tagvalue1")
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.field("field1", value)
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)
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write_api.write(bucket=bucket, org="gbucchino", record=point)
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time.sleep(1) # separate points by 1 second
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BIN
load_bpf
Executable file
BIN
load_bpf
Executable file
Binary file not shown.
93
load_bpf.c
93
load_bpf.c
@ -1,4 +1,3 @@
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#include <stdlib.h>
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#include <stdio.h>
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#include <bpf/bpf.h>
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#include <bpf/libbpf.h>
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@ -7,40 +6,12 @@
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#include <arpa/inet.h>
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#include "common.h"
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#include <unistd.h>
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#include <errno.h>
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#include "ic.h"
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#define BUF_SIZE 300
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#define BUCKET_SIZE 16 // Bucket size for InfluxDB
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#define INFLUXDB_SIZE 64 // Host and ordID size for InfluxDB
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#define TOKEN_SIZE 128 // Token size for InfluxDB
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#define CNT_ARGS 5 // Number of args
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static void clean_obj(struct bpf_object *obj){
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printf("Cleaning\n");
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bpf_object__close(obj);
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}
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static void usage(char *app){
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printf("Usage: %s <host> <ordID> <token> <bucket>\n", app);
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}
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static int check_arguments(int argc, char *argv[]){
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if (argc < 1){
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usage(argv[0]);
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return -1;
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}
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if (strcmp(argv[1], "--no-influxdb") == 0)
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return 0;
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if (argc < CNT_ARGS){
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usage(argv[0]);
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return -1;
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}
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return argc; // Return the number of arguments
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}
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int main(int argc, char *argv[]){
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}
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int main(void){
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const char *fileObj = "tp_tcp.o";
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struct bpf_object *obj;
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struct bpf_program *program;
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@ -54,51 +25,24 @@ int main(int argc, char *argv[]){
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int keys = 0;
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int indexPackets = 0;
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int index = 0;
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char buf[BUF_SIZE];
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char host[INFLUXDB_SIZE];
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char orgID[INFLUXDB_SIZE];
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char token[TOKEN_SIZE];
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char bucket[BUCKET_SIZE];
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int use_influxdb = 0;
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int debug = 1;
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// We get args
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err = check_arguments(argc, argv);
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if (err == -1)
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return -1;
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if (err == CNT_ARGS){
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strncpy(host, argv[1], INFLUXDB_SIZE);
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strncpy(orgID, argv[2], INFLUXDB_SIZE);
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strncpy(token, argv[3], TOKEN_SIZE);
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strncpy(bucket, argv[4], BUCKET_SIZE);
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use_influxdb = 1;
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}
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// Connect to InfluxDB
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if (use_influxdb) {
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ic_influx_database(host, 8086, bucket);
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ic_influx_orgID(orgID);
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ic_influx_token(token);
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}
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obj = bpf_object__open_file(fileObj, NULL);
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if (!obj){
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printf("Failed to open %s\n", fileObj);
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return -1;
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}
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//LIBBPF_OPTS(bpf_map_create_opts, opts, .map_flags = BPF_F_MMAPABLE);
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//map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(int), sizeof(struct reset), 4096, BPF_ANY);
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//map_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, sizeof(int), sizeof(struct reset), 4096, BPF_ANY);
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err = bpf_object__load(obj);
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if (err){
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printf("%s\n", strerror(errno));
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printf("Failed to load object\n");
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clean_obj(obj);
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return -1;
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}
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program = bpf_object__find_program_by_name(obj, "tcp_rst_stats");
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program = bpf_object__find_program_by_name(obj, "tcp_retransmit");
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if (!program){
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printf("Failed to find the program\n");
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clean_obj(obj);
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@ -147,42 +91,31 @@ int main(int argc, char *argv[]){
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__s16 f = AF_INET;
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err = bpf_map_update_elem(map_fd_filter_family, &keys, &f, BPF_ANY);
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while(1){
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// Get the index
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// and we compare with the local variable
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// If it's different, we get the new variable
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err = bpf_map_lookup_elem(map_fd_index, &keys, &indexPackets);
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// We have a new packet
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if (indexPackets > index){
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index = indexPackets;
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printf("Index: %d %d\n", index, indexPackets);
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err = bpf_map_lookup_elem(map_fd, &keys, &s_reset);
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if (err == 0){
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struct in_addr *src = (struct in_addr*)&s_reset.saddr;
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struct in_addr *dest = (struct in_addr*)&s_reset.daddr;
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char *s = inet_ntoa(*src);
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char *d;
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char tmp[35];
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int lastValue;
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memcpy(tmp, s, 35);
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d = inet_ntoa(*dest);
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char *d = inet_ntoa(*dest);
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if (debug)
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printf("Sport: %d; dport: %d %d %d %s - %s\n", s_reset.sport, s_reset.dport, s_reset.family, s_reset.proto, tmp, d);
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printf("Sport: %d; dport: %d %d %d %s - %s\n", s_reset.sport, s_reset.dport, s_reset.family, s_reset.proto, tmp, d);
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if (use_influxdb) {
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printf("Send data to influx\n");
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// Send data to InfluxDB
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snprintf(buf, BUF_SIZE, "host=%s", s);
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ic_tags(buf);
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ic_measure("tcp_reset");
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ic_long("value", 1);
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ic_measureend();
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ic_push();
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|
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memset(buf, 0, BUF_SIZE);
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}
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}
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memset(&s_reset, 0, sizeof(struct reset));
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//sleep(1);
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}
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}
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|
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|
BIN
main
Executable file
BIN
main
Executable file
Binary file not shown.
25
main.c
Normal file
25
main.c
Normal file
@ -0,0 +1,25 @@
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#define BPF_NO_GLOBAL_DATA
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#include <stdio.h>
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#include <unistd.h>
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#include "ic.h"
|
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|
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int main(int argc, char *argv[], char *argp[]){
|
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printf("Hello world\n");
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char buf[300];
|
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|
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ic_influx_database("192.168.1.68", 8086, "tcp");
|
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ic_influx_userpw("admin", "Geta,Fte#");
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ic_debug(2);
|
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|
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snprintf(buf, 300, "host=192.168.1.68");
|
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ic_tags(buf);
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|
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ic_measure("tcp_reset");
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ic_string("ipsrc", "192.168.1.1");
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|
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ic_measureend();
|
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ic_push();
|
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|
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return 0;
|
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}
|
9
main.py
Normal file
9
main.py
Normal file
@ -0,0 +1,9 @@
|
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#!/usr/bin/env python3
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|
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from bcc import BPF
|
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|
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with open("tp_tcp.c", 'r') as f:
|
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data = f.read()
|
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|
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b = BPF(text=data)
|
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#b = BPF(src_file="tp_tcp_py.c")
|
30
prometheus.py
Normal file
30
prometheus.py
Normal file
@ -0,0 +1,30 @@
|
||||
from prometheus_client import start_http_server, Summary, Counter
|
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import random
|
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import time
|
||||
|
||||
# Create a metric to track time spent and requests made.
|
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#REQUEST_TIME = Summary('request_processing_seconds', 'Time spent processing request', 'foo')
|
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#REQUEST_TIME = Summary('request_processing_seconds', 'foo')
|
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|
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|
||||
# Decorate function with metric.
|
||||
#@REQUEST_TIME.time()
|
||||
#def process_request(t):
|
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# """A dummy function that takes some time."""
|
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# time.sleep(t)
|
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|
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c = Counter("tcp_reset_stats", "TCP RST stats")
|
||||
def tcp_rst_stats():
|
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c.inc()
|
||||
|
||||
if __name__ == '__main__':
|
||||
# Start up the server to expose the metrics.
|
||||
start_http_server(8000)
|
||||
# Generate some requests.
|
||||
while True:
|
||||
# process_request(random.random())
|
||||
|
||||
# Count
|
||||
print("Inc")
|
||||
tcp_rst_stats()
|
||||
time.sleep(30)
|
@ -1,23 +0,0 @@
|
||||
import socket
|
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import struct
|
||||
|
||||
def server(host, port):
|
||||
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM, 0)
|
||||
l_onoff = 1
|
||||
l_linger = 0
|
||||
s.setsockopt(
|
||||
socket.SOL_SOCKET,
|
||||
socket.SO_LINGER,
|
||||
struct.pack('ii', l_onoff, l_linger)
|
||||
)
|
||||
s.bind(('', port))
|
||||
s.listen(5)
|
||||
|
||||
while 1:
|
||||
skclt, addrclt = s.accept()
|
||||
print(f"New connection from client: {addrclt}")
|
||||
|
||||
|
||||
skclt.close()
|
||||
|
||||
server('0.0.0.0', 8080)
|
@ -1,12 +0,0 @@
|
||||
#!/usr/bin/bash
|
||||
|
||||
curl -i -X POST "http://192.168.1.68:8086/api/v2/query?bucket=tcp_metrics&orgID=f32d493484526abc" \
|
||||
--header "Authorization: Token $1" \
|
||||
--header "Accept: application/csv" \
|
||||
--header "Content-Type: application/vnd.flux" \
|
||||
--data 'from(bucket: "tcp_metrics")
|
||||
|> range(start: -5m)
|
||||
|> filter(fn: (r) => r["_measurement"] == "tcp_reset")
|
||||
|> filter(fn: (r) => r["host"] == "127.0.0.1")
|
||||
|> filter(fn: (r) => r["_field"] == "value")
|
||||
|> yield(name: "mean")'
|
@ -1,5 +0,0 @@
|
||||
#!/usr/bin/bash
|
||||
|
||||
curl -i -X POST "http://localhost:8086/api/v2/write?bucket=tcp_metrics&orgID=392fcb79fc296d8e" \
|
||||
--header "Authorization: Token $1" \
|
||||
--data "cpu_load_short,host=server01, value=1"
|
38
tp_tcp.c
38
tp_tcp.c
@ -10,7 +10,22 @@
|
||||
char LICENSE[] SEC("license") = "Dual BSD/GPL";
|
||||
|
||||
|
||||
// Format: /sys/kernel/debug/tracing/events/tcp/tcp_send_reset/format
|
||||
struct ctx_receive_reset {
|
||||
__u16 common_type; // unsigned short
|
||||
__u8 common_flags; // unsigned char
|
||||
__u8 common_count; // unsigned char
|
||||
__s32 pid; // int
|
||||
|
||||
const void *skaddr;
|
||||
__u16 sport;
|
||||
__u16 dport;
|
||||
__u16 family;
|
||||
__u8 saddr[4];
|
||||
__u8 daddr[4];
|
||||
__u8 saddr_v6[16];
|
||||
__u8 daddr_v6[16];
|
||||
__u64 sock_cookie;
|
||||
};
|
||||
struct ctx_send_reset {
|
||||
__u16 common_type; // unsigned short
|
||||
__u8 common_flags; // unsigned char
|
||||
@ -59,13 +74,31 @@ struct {
|
||||
// sudo tcpdump -i any 'tcp[13] & 4 != 0' -n -> filter TCP reset flags
|
||||
|
||||
/*
|
||||
* This project do not trace any sniffing ports, because, the tracepoint tcp:tcp_send_reset
|
||||
* works only for an establish socket, but, if you have a lot of TCP RST, you can have
|
||||
* an issue with your system
|
||||
*/
|
||||
|
||||
/*
|
||||
* Identify all tracepoint available
|
||||
* - cat /sys/kernel/tracing/available_events
|
||||
* Enable an event:
|
||||
* - echo 'tcp_receive_reset' >> /sys/kernel/tracing/set_event -> important to add the '>>'
|
||||
* Docs: https://docs.kernel.org/trace/events.html
|
||||
* https://events.linuxfoundation.org/wp-content/uploads/2022/10/elena-zannoni-tracing-tutorial-LF-2021.pdf
|
||||
* https://docs.kernel.org/trace/tracepoints.html
|
||||
* Why we need to detect RST:
|
||||
* When we scan the port, the scanner send an SYN flag and if the port is block, we receive a RST flag:
|
||||
* listening on any, link-type LINUX_SLL2 (Linux cooked v2), snapshot length 262144 bytes
|
||||
10:48:28.531295 lo In IP localhost.43961 > localhost.tproxy: Flags [S], seq 2197047013, win 1024, options [mss 1460], length 0
|
||||
10:48:28.531306 lo In IP localhost.tproxy > localhost.43961: Flags [R.], seq 0, ack 2197047014, win 0, length 0
|
||||
* But we can also block all receive RST: iptables -I INPUT -p tcp --dport <port> -j REJECT --reject-with tcp-reset
|
||||
*/
|
||||
|
||||
//SEC("tp/tcp_retransmit_synack")
|
||||
//SEC("tracepoint/tcp/tcp_receive_reset")
|
||||
SEC("tracepoint/tcp/tcp_send_reset")
|
||||
int tcp_rst_stats(struct ctx_send_reset *ctx){
|
||||
int tcp_retransmit(struct ctx_send_reset *ctx){
|
||||
struct reset s_reset = {};
|
||||
int *index;
|
||||
int keys = 0;
|
||||
@ -87,6 +120,7 @@ int tcp_rst_stats(struct ctx_send_reset *ctx){
|
||||
if (!index)
|
||||
return 0;
|
||||
|
||||
|
||||
// Get the family of the socket
|
||||
bpf_probe_read_kernel(&family, sizeof(family), &sk->__sk_common.skc_family);
|
||||
if (family != *f_family)
|
||||
|
BIN
tp_tcp.o
Normal file
BIN
tp_tcp.o
Normal file
Binary file not shown.
149
tp_tcp_py.c
Normal file
149
tp_tcp_py.c
Normal file
@ -0,0 +1,149 @@
|
||||
#define BPF_NO_GLOBAL_DATA
|
||||
//#define __TARGET_ARCH_x86
|
||||
#include "vmlinux.h"
|
||||
#include <string.h>
|
||||
#include <bpf/bpf_helpers.h>
|
||||
#include <bpf/bpf_tracing.h>
|
||||
#include <bpf/bpf_core_read.h>
|
||||
#include "common.h"
|
||||
|
||||
char LICENSE[] SEC("license") = "Dual BSD/GPL";
|
||||
|
||||
|
||||
struct ctx_receive_reset {
|
||||
__u16 common_type; // unsigned short
|
||||
__u8 common_flags; // unsigned char
|
||||
__u8 common_count; // unsigned char
|
||||
__s32 pid; // int
|
||||
|
||||
const void *skaddr;
|
||||
__u16 sport;
|
||||
__u16 dport;
|
||||
__u16 family;
|
||||
__u8 saddr[4];
|
||||
__u8 daddr[4];
|
||||
__u8 saddr_v6[16];
|
||||
__u8 daddr_v6[16];
|
||||
__u64 sock_cookie;
|
||||
};
|
||||
struct ctx_send_reset {
|
||||
__u16 common_type; // unsigned short
|
||||
__u8 common_flags; // unsigned char
|
||||
__u8 common_count; // unsigned char
|
||||
__s32 pid; // int
|
||||
|
||||
const void *skbaddr;
|
||||
const void *skaddr;
|
||||
__s32 state; // int
|
||||
__u16 sport;
|
||||
__u16 dport;
|
||||
__u8 saddr[4];
|
||||
__u8 daddr[4];
|
||||
__u8 saddr_v6[16];
|
||||
__u8 daddr_v6[16];
|
||||
};
|
||||
|
||||
struct {
|
||||
__uint(type, BPF_MAP_TYPE_ARRAY);
|
||||
__uint(max_entries, 4096);
|
||||
__type(key, 1);
|
||||
__type(value, __s32);
|
||||
} tcp_stats_index SEC(".maps");
|
||||
|
||||
struct {
|
||||
__uint(type, BPF_MAP_TYPE_ARRAY);
|
||||
__uint(max_entries, 4096);
|
||||
__type(key, 4);
|
||||
__type(value, struct reset);
|
||||
} tcp_reset_stats SEC(".maps");
|
||||
|
||||
struct {
|
||||
__uint(type, BPF_MAP_TYPE_ARRAY);
|
||||
__uint(max_entries, 1);
|
||||
__type(key, __s32);
|
||||
__type(value, __u16);
|
||||
} filter_family SEC(".maps");
|
||||
|
||||
struct {
|
||||
__uint(type, BPF_MAP_TYPE_ARRAY);
|
||||
__uint(max_entries, 1);
|
||||
__type(key, __s32);
|
||||
__type(value, __u16);
|
||||
} filter_sport SEC(".maps");
|
||||
|
||||
// sudo tcpdump -i any 'tcp[13] & 4 != 0' -n -> filter TCP reset flags
|
||||
|
||||
/*
|
||||
* This project do not trace any sniffing ports, because, the tracepoint tcp:tcp_send_reset
|
||||
* works only for an establish socket, but, if you have a lot of TCP RST, you can have
|
||||
* an issue with your system
|
||||
*/
|
||||
|
||||
/*
|
||||
* Identify all tracepoint available
|
||||
* - cat /sys/kernel/tracing/available_events
|
||||
* Enable an event:
|
||||
* - echo 'tcp_receive_reset' >> /sys/kernel/tracing/set_event -> important to add the '>>'
|
||||
* Docs: https://docs.kernel.org/trace/events.html
|
||||
* https://events.linuxfoundation.org/wp-content/uploads/2022/10/elena-zannoni-tracing-tutorial-LF-2021.pdf
|
||||
* https://docs.kernel.org/trace/tracepoints.html
|
||||
* Why we need to detect RST:
|
||||
* When we scan the port, the scanner send an SYN flag and if the port is block, we receive a RST flag:
|
||||
* listening on any, link-type LINUX_SLL2 (Linux cooked v2), snapshot length 262144 bytes
|
||||
10:48:28.531295 lo In IP localhost.43961 > localhost.tproxy: Flags [S], seq 2197047013, win 1024, options [mss 1460], length 0
|
||||
10:48:28.531306 lo In IP localhost.tproxy > localhost.43961: Flags [R.], seq 0, ack 2197047014, win 0, length 0
|
||||
* But we can also block all receive RST: iptables -I INPUT -p tcp --dport <port> -j REJECT --reject-with tcp-reset
|
||||
*/
|
||||
|
||||
//SEC("tp/tcp_retransmit_synack")
|
||||
//SEC("tracepoint/tcp/tcp_receive_reset")
|
||||
//SEC("tracepoint/tcp/tcp_send_reset")
|
||||
int tcp_retransmit(struct ctx_send_reset *ctx){
|
||||
struct reset s_reset = {};
|
||||
int *index;
|
||||
int keys = 0;
|
||||
struct sock *sk;
|
||||
__u16 family;
|
||||
__s16 *f_family;
|
||||
__u16 proto;
|
||||
int err;
|
||||
|
||||
memset(&s_reset, 0, sizeof(struct reset));
|
||||
|
||||
// Get filter
|
||||
sk = (struct sock*)ctx->skaddr;
|
||||
f_family = bpf_map_lookup_elem(&filter_family, &keys);
|
||||
if (!f_family)
|
||||
return 0;
|
||||
|
||||
index = bpf_map_lookup_elem(&tcp_stats_index, &keys);
|
||||
if (!index)
|
||||
return 0;
|
||||
|
||||
|
||||
// Get the family of the socket
|
||||
bpf_probe_read_kernel(&family, sizeof(family), &sk->__sk_common.skc_family);
|
||||
if (family != *f_family)
|
||||
return 0;
|
||||
|
||||
// Get and update the index in the map
|
||||
*index += 1;
|
||||
|
||||
// Proto type: here it's 6 (TCP)
|
||||
bpf_probe_read_kernel(&proto, sizeof(proto), &sk->sk_protocol);
|
||||
|
||||
memcpy(s_reset.saddr, ctx->saddr, 4);
|
||||
memcpy(s_reset.daddr, ctx->daddr, 4);
|
||||
|
||||
//bpf_probe_read_kernel(&s_reset.saddr, 4, &ctx->saddr);
|
||||
//bpf_probe_read_kernel(&s_reset.daddr, 4, &ctx->daddr);
|
||||
|
||||
s_reset.sport = ctx->sport;
|
||||
s_reset.dport = ctx->dport;
|
||||
s_reset.family = family;
|
||||
s_reset.proto = proto;
|
||||
|
||||
bpf_printk("BPF detected TCP send reset %d %d", s_reset.sport, s_reset.dport);
|
||||
bpf_map_update_elem(&tcp_reset_stats, &keys, &s_reset, BPF_ANY);
|
||||
return 0;
|
||||
}
|
Loading…
Reference in New Issue
Block a user