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-rw-r--r--tools/bpf/bpftool/common.c405
1 files changed, 405 insertions, 0 deletions
diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c
new file mode 100644
index 000000000000..2bd3b280e6dd
--- /dev/null
+++ b/tools/bpf/bpftool/common.c
@@ -0,0 +1,405 @@
+/*
+ * 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 <fts.h>
+#include <libgen.h>
+#include <mntent.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/mount.h>
+#include <sys/types.h>
+#include <sys/vfs.h>
+
+#include <bpf.h>
+
+#include "main.h"
+
+void p_err(const char *fmt, ...)
+{
+ va_list ap;
+
+ va_start(ap, fmt);
+ if (json_output) {
+ jsonw_start_object(json_wtr);
+ jsonw_name(json_wtr, "error");
+ jsonw_vprintf_enquote(json_wtr, fmt, ap);
+ jsonw_end_object(json_wtr);
+ } else {
+ fprintf(stderr, "Error: ");
+ vfprintf(stderr, fmt, ap);
+ fprintf(stderr, "\n");
+ }
+ va_end(ap);
+}
+
+void p_info(const char *fmt, ...)
+{
+ va_list ap;
+
+ if (json_output)
+ return;
+
+ va_start(ap, fmt);
+ vfprintf(stderr, fmt, ap);
+ fprintf(stderr, "\n");
+ va_end(ap);
+}
+
+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;
+}
+
+static int mnt_bpffs(const char *target, char *buff, size_t bufflen)
+{
+ bool bind_done = false;
+
+ while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
+ if (errno != EINVAL || bind_done) {
+ snprintf(buff, bufflen,
+ "mount --make-private %s failed: %s",
+ target, strerror(errno));
+ return -1;
+ }
+
+ if (mount(target, target, "none", MS_BIND, NULL)) {
+ snprintf(buff, bufflen,
+ "mount --bind %s %s failed: %s",
+ target, target, strerror(errno));
+ return -1;
+ }
+
+ bind_done = true;
+ }
+
+ if (mount("bpf", target, "bpf", 0, "mode=0700")) {
+ snprintf(buff, bufflen, "mount -t bpf bpf %s failed: %s",
+ target, strerror(errno));
+ return -1;
+ }
+
+ return 0;
+}
+
+int open_obj_pinned(char *path)
+{
+ int fd;
+
+ fd = bpf_obj_get(path);
+ if (fd < 0) {
+ p_err("bpf obj get (%s): %s", path,
+ errno == EACCES && !is_bpffs(dirname(path)) ?
+ "directory not in bpf file system (bpffs)" :
+ strerror(errno));
+ return -1;
+ }
+
+ return fd;
+}
+
+int open_obj_pinned_any(char *path, enum bpf_obj_type exp_type)
+{
+ enum bpf_obj_type type;
+ int fd;
+
+ fd = open_obj_pinned(path);
+ if (fd < 0)
+ return -1;
+
+ type = get_fd_type(fd);
+ if (type < 0) {
+ close(fd);
+ return type;
+ }
+ if (type != exp_type) {
+ p_err("incorrect object type: %s", 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))
+{
+ char err_str[ERR_MAX_LEN];
+ unsigned int id;
+ char *endptr;
+ char *file;
+ char *dir;
+ int err;
+ int fd;
+
+ if (!is_prefix(*argv, "id")) {
+ p_err("expected 'id' got %s", *argv);
+ return -1;
+ }
+ NEXT_ARG();
+
+ id = strtoul(*argv, &endptr, 0);
+ if (*endptr) {
+ p_err("can't parse %s as ID", *argv);
+ return -1;
+ }
+ NEXT_ARG();
+
+ if (argc != 1)
+ usage();
+
+ fd = get_fd_by_id(id);
+ if (fd < 0) {
+ p_err("can't get prog by id (%u): %s", id, strerror(errno));
+ return -1;
+ }
+
+ err = bpf_obj_pin(fd, *argv);
+ if (!err)
+ goto out_close;
+
+ file = malloc(strlen(*argv) + 1);
+ strcpy(file, *argv);
+ dir = dirname(file);
+
+ if (errno != EPERM || is_bpffs(dir)) {
+ p_err("can't pin the object (%s): %s", *argv, strerror(errno));
+ goto out_free;
+ }
+
+ /* Attempt to mount bpffs, then retry pinning. */
+ err = mnt_bpffs(dir, err_str, ERR_MAX_LEN);
+ if (!err) {
+ err = bpf_obj_pin(fd, *argv);
+ if (err)
+ p_err("can't pin the object (%s): %s", *argv,
+ strerror(errno));
+ } else {
+ err_str[ERR_MAX_LEN - 1] = '\0';
+ p_err("can't mount BPF file system to pin the object (%s): %s",
+ *argv, err_str);
+ }
+
+out_free:
+ free(file);
+out_close:
+ close(fd);
+ return err;
+}
+
+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) {
+ p_err("can't read link type: %s", strerror(errno));
+ return -1;
+ }
+ if (n == sizeof(path)) {
+ p_err("can't read link type: path too long!");
+ 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) {
+ p_err("can't open fdinfo: %s", 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]) {
+ p_err("malformed fdinfo!?");
+ free(line);
+ return NULL;
+ }
+ value++;
+
+ len = strlen(value);
+ memmove(line, value, len);
+ line[len - 1] = '\0';
+
+ return line;
+ }
+
+ p_err("key '%s' not found in fdinfo", key);
+ free(line);
+ fclose(fdi);
+ return NULL;
+}
+
+void print_hex_data_json(uint8_t *data, size_t len)
+{
+ unsigned int i;
+
+ jsonw_start_array(json_wtr);
+ for (i = 0; i < len; i++)
+ jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
+ jsonw_end_array(json_wtr);
+}
+
+int build_pinned_obj_table(struct pinned_obj_table *tab,
+ enum bpf_obj_type type)
+{
+ struct bpf_prog_info pinned_info = {};
+ struct pinned_obj *obj_node = NULL;
+ __u32 len = sizeof(pinned_info);
+ struct mntent *mntent = NULL;
+ enum bpf_obj_type objtype;
+ FILE *mntfile = NULL;
+ FTSENT *ftse = NULL;
+ FTS *fts = NULL;
+ int fd, err;
+
+ mntfile = setmntent("/proc/mounts", "r");
+ if (!mntfile)
+ return -1;
+
+ while ((mntent = getmntent(mntfile))) {
+ char *path[] = { mntent->mnt_dir, NULL };
+
+ if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
+ continue;
+
+ fts = fts_open(path, 0, NULL);
+ if (!fts)
+ continue;
+
+ while ((ftse = fts_read(fts))) {
+ if (!(ftse->fts_info & FTS_F))
+ continue;
+ fd = open_obj_pinned(ftse->fts_path);
+ if (fd < 0)
+ continue;
+
+ objtype = get_fd_type(fd);
+ if (objtype != type) {
+ close(fd);
+ continue;
+ }
+ memset(&pinned_info, 0, sizeof(pinned_info));
+ err = bpf_obj_get_info_by_fd(fd, &pinned_info, &len);
+ if (err) {
+ close(fd);
+ continue;
+ }
+
+ obj_node = malloc(sizeof(*obj_node));
+ if (!obj_node) {
+ close(fd);
+ fts_close(fts);
+ fclose(mntfile);
+ return -1;
+ }
+
+ memset(obj_node, 0, sizeof(*obj_node));
+ obj_node->id = pinned_info.id;
+ obj_node->path = strdup(ftse->fts_path);
+ hash_add(tab->table, &obj_node->hash, obj_node->id);
+
+ close(fd);
+ }
+ fts_close(fts);
+ }
+ fclose(mntfile);
+ return 0;
+}
+
+void delete_pinned_obj_table(struct pinned_obj_table *tab)
+{
+ struct pinned_obj *obj;
+ struct hlist_node *tmp;
+ unsigned int bkt;
+
+ hash_for_each_safe(tab->table, bkt, tmp, obj, hash) {
+ hash_del(&obj->hash);
+ free(obj->path);
+ free(obj);
+ }
+}
generated by cgit (git 2.34.1) at 2024-05-02 09:42:57 +0000