Quelle  module_attach.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Facebook */

#include <test_progs.h>
#include <stdbool.h>
#include "test_module_attach.skel.h"
#include "testing_helpers.h"

static int duration;

static int trigger_module_test_writable(int *val)
{
 int fd, err;
 char buf[65];
 ssize_t rd;

 fd = open(BPF_TESTMOD_TEST_FILE, O_RDONLY);
 err = -errno;
 if (!ASSERT_GE(fd, 0, "testmode_file_open"))
  return err;

 rd = read(fd, buf, sizeof(buf) - 1);
 err = -errno;
 if (!ASSERT_GT(rd, 0, "testmod_file_rd_val")) {
  close(fd);
  return err;
 }

 buf[rd] = '\0';
 *val = strtol(buf, NULL, 0);
 close(fd);

 return 0;
}

void test_module_attach(void)
{
 const int READ_SZ = 456;
 const int WRITE_SZ = 457;
 struct test_module_attach* skel;
 struct test_module_attach__bss *bss;
 struct bpf_link *link;
 int err;
 int writable_val = 0;

 skel = test_module_attach__open();
 if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
  return;

 err = bpf_program__set_attach_target(skel->progs.handle_fentry_manual,
          0, "bpf_testmod_test_read");
 ASSERT_OK(err, "set_attach_target");

 err = bpf_program__set_attach_target(skel->progs.handle_fentry_explicit_manual,
          0, "bpf_testmod:bpf_testmod_test_read");
 ASSERT_OK(err, "set_attach_target_explicit");

 err = test_module_attach__load(skel);
 if (CHECK(err, "skel_load", "failed to load skeleton\n"))
  return;

 bss = skel->bss;

 err = test_module_attach__attach(skel);
 if (CHECK(err, "skel_attach", "skeleton attach failed: %d\n", err))
  goto cleanup;

 /* trigger tracepoint */
 ASSERT_OK(trigger_module_test_read(READ_SZ), "trigger_read");
 ASSERT_OK(trigger_module_test_write(WRITE_SZ), "trigger_write");

 ASSERT_EQ(bss->raw_tp_read_sz, READ_SZ, "raw_tp");
 ASSERT_EQ(bss->raw_tp_bare_write_sz, WRITE_SZ, "raw_tp_bare");
 ASSERT_EQ(bss->tp_btf_read_sz, READ_SZ, "tp_btf");
 ASSERT_EQ(bss->fentry_read_sz, READ_SZ, "fentry");
 ASSERT_EQ(bss->fentry_manual_read_sz, READ_SZ, "fentry_manual");
 ASSERT_EQ(bss->fentry_explicit_read_sz, READ_SZ, "fentry_explicit");
 ASSERT_EQ(bss->fentry_explicit_manual_read_sz, READ_SZ, "fentry_explicit_manual");
 ASSERT_EQ(bss->fexit_read_sz, READ_SZ, "fexit");
 ASSERT_EQ(bss->fexit_ret, -EIO, "fexit_tet");
 ASSERT_EQ(bss->fmod_ret_read_sz, READ_SZ, "fmod_ret");

 bss->raw_tp_writable_bare_early_ret = true;
 bss->raw_tp_writable_bare_out_val = 0xf1f2f3f4;
 ASSERT_OK(trigger_module_test_writable(&writable_val),
    "trigger_writable");
 ASSERT_EQ(bss->raw_tp_writable_bare_in_val, 1024, "writable_test_in");
 ASSERT_EQ(bss->raw_tp_writable_bare_out_val, writable_val,
    "writable_test_out");

 test_module_attach__detach(skel);

 /* attach fentry/fexit and make sure it gets module reference */
 link = bpf_program__attach(skel->progs.handle_fentry);
 if (!ASSERT_OK_PTR(link, "attach_fentry"))
  goto cleanup;

 ASSERT_ERR(unload_bpf_testmod(false), "unload_bpf_testmod");
 bpf_link__destroy(link);

 link = bpf_program__attach(skel->progs.handle_fexit);
 if (!ASSERT_OK_PTR(link, "attach_fexit"))
  goto cleanup;

 ASSERT_ERR(unload_bpf_testmod(false), "unload_bpf_testmod");
 bpf_link__destroy(link);

 link = bpf_program__attach(skel->progs.kprobe_multi);
 if (!ASSERT_OK_PTR(link, "attach_kprobe_multi"))
  goto cleanup;

 ASSERT_ERR(unload_bpf_testmod(false), "unload_bpf_testmod");
 bpf_link__destroy(link);

cleanup:
 test_module_attach__destroy(skel);
}