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/*
* Copyright (C) 2017 Netronome Systems, Inc.
*
* This software is dual licensed under the GNU General License Version 2,
* June 1991 as shown in the file COPYING in the top-level directory of this
* source tree or the BSD 2-Clause License provided below. You have the
* option to license this software under the complete terms of either license.
*
* The BSD 2-Clause License:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* 1. Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* 2. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
/* Author: Jakub Kicinski <kubakici@wp.pl> */
#include <errno.h>
#include <libgen.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <linux/limits.h>
#include <linux/magic.h>
#include <sys/types.h>
#include <sys/vfs.h>
#include <bpf.h>
#include "main.h"
static bool is_bpffs(char *path)
{
struct statfs st_fs;
if (statfs(path, &st_fs) < 0)
return false;
return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;
}
int open_obj_pinned_any(char *path, enum bpf_obj_type exp_type)
{
enum bpf_obj_type type;
int fd;
fd = bpf_obj_get(path);
if (fd < 0) {
err("bpf obj get (%s): %s\n", path,
errno == EACCES && !is_bpffs(dirname(path)) ?
"directory not in bpf file system (bpffs)" :
strerror(errno));
return -1;
}
type = get_fd_type(fd);
if (type < 0) {
close(fd);
return type;
}
if (type != exp_type) {
err("incorrect object type: %s\n", get_fd_type_name(type));
close(fd);
return -1;
}
return fd;
}
int do_pin_any(int argc, char **argv, int (*get_fd_by_id)(__u32))
{
unsigned int id;
char *endptr;
int err;
int fd;
if (!is_prefix(*argv, "id")) {
err("expected 'id' got %s\n", *argv);
return -1;
}
NEXT_ARG();
id = strtoul(*argv, &endptr, 0);
if (*endptr) {
err("can't parse %s as ID\n", *argv);
return -1;
}
NEXT_ARG();
if (argc != 1)
usage();
fd = get_fd_by_id(id);
if (fd < 0) {
err("can't get prog by id (%u): %s\n", id, strerror(errno));
return -1;
}
err = bpf_obj_pin(fd, *argv);
close(fd);
if (err) {
err("can't pin the object (%s): %s\n", *argv,
errno == EACCES && !is_bpffs(dirname(*argv)) ?
"directory not in bpf file system (bpffs)" :
strerror(errno));
return -1;
}
return 0;
}
const char *get_fd_type_name(enum bpf_obj_type type)
{
static const char * const names[] = {
[BPF_OBJ_UNKNOWN] = "unknown",
[BPF_OBJ_PROG] = "prog",
[BPF_OBJ_MAP] = "map",
};
if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
return names[BPF_OBJ_UNKNOWN];
return names[type];
}
int get_fd_type(int fd)
{
char path[PATH_MAX];
char buf[512];
ssize_t n;
snprintf(path, sizeof(path), "/proc/%d/fd/%d", getpid(), fd);
n = readlink(path, buf, sizeof(buf));
if (n < 0) {
err("can't read link type: %s\n", strerror(errno));
return -1;
}
if (n == sizeof(path)) {
err("can't read link type: path too long!\n");
return -1;
}
if (strstr(buf, "bpf-map"))
return BPF_OBJ_MAP;
else if (strstr(buf, "bpf-prog"))
return BPF_OBJ_PROG;
return BPF_OBJ_UNKNOWN;
}
char *get_fdinfo(int fd, const char *key)
{
char path[PATH_MAX];
char *line = NULL;
size_t line_n = 0;
ssize_t n;
FILE *fdi;
snprintf(path, sizeof(path), "/proc/%d/fdinfo/%d", getpid(), fd);
fdi = fopen(path, "r");
if (!fdi) {
err("can't open fdinfo: %s\n", strerror(errno));
return NULL;
}
while ((n = getline(&line, &line_n, fdi))) {
char *value;
int len;
if (!strstr(line, key))
continue;
fclose(fdi);
value = strchr(line, '\t');
if (!value || !value[1]) {
err("malformed fdinfo!?\n");
free(line);
return NULL;
}
value++;
len = strlen(value);
memmove(line, value, len);
line[len - 1] = '\0';
return line;
}
err("key '%s' not found in fdinfo\n", key);
free(line);
fclose(fdi);
return NULL;
}
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