cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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lwt_len_hist_user.c (1653B)

      1// SPDX-License-Identifier: GPL-2.0
      2#include <linux/unistd.h>
      3#include <linux/bpf.h>
      4
      5#include <stdlib.h>
      6#include <stdio.h>
      7#include <unistd.h>
      8#include <string.h>
      9#include <errno.h>
     10#include <arpa/inet.h>
     11
     12#include <bpf/bpf.h>
     13#include "bpf_util.h"
     14
     15#define MAX_INDEX 64
     16#define MAX_STARS 38
     17
     18static void stars(char *str, long val, long max, int width)
     19{
     20	int i;
     21
     22	for (i = 0; i < (width * val / max) - 1 && i < width - 1; i++)
     23		str[i] = '*';
     24	if (val > max)
     25		str[i - 1] = '+';
     26	str[i] = '\0';
     27}
     28
     29int main(int argc, char **argv)
     30{
     31	unsigned int nr_cpus = bpf_num_possible_cpus();
     32	const char *map_filename = "/sys/fs/bpf/tc/globals/lwt_len_hist_map";
     33	uint64_t values[nr_cpus], sum, max_value = 0, data[MAX_INDEX] = {};
     34	uint64_t key = 0, next_key, max_key = 0;
     35	char starstr[MAX_STARS];
     36	int i, map_fd;
     37
     38	map_fd = bpf_obj_get(map_filename);
     39	if (map_fd < 0) {
     40		fprintf(stderr, "bpf_obj_get(%s): %s(%d)\n",
     41			map_filename, strerror(errno), errno);
     42		return -1;
     43	}
     44
     45	while (bpf_map_get_next_key(map_fd, &key, &next_key) == 0) {
     46		if (next_key >= MAX_INDEX) {
     47			fprintf(stderr, "Key %lu out of bounds\n", next_key);
     48			continue;
     49		}
     50
     51		bpf_map_lookup_elem(map_fd, &next_key, values);
     52
     53		sum = 0;
     54		for (i = 0; i < nr_cpus; i++)
     55			sum += values[i];
     56
     57		data[next_key] = sum;
     58		if (sum && next_key > max_key)
     59			max_key = next_key;
     60
     61		if (sum > max_value)
     62			max_value = sum;
     63
     64		key = next_key;
     65	}
     66
     67	for (i = 1; i <= max_key + 1; i++) {
     68		stars(starstr, data[i - 1], max_value, MAX_STARS);
     69		printf("%8ld -> %-8ld : %-8ld |%-*s|\n",
     70		       (1l << i) >> 1, (1l << i) - 1, data[i - 1],
     71		       MAX_STARS, starstr);
     72	}
     73
     74	close(map_fd);
     75
     76	return 0;
     77}