1 // SPDX-License-Identifier: GPL-2.0 2 #include "bpf/libbpf.h" 3 #include "changes_pkt_data_freplace.skel.h" 4 #include "changes_pkt_data.skel.h" 5 #include <test_progs.h> 6 7 static void print_verifier_log(const char *log) 8 { 9 if (env.verbosity >= VERBOSE_VERY) 10 fprintf(stdout, "VERIFIER LOG:\n=============\n%s=============\n", log); 11 } 12 13 static void test_aux(const char *main_prog_name, 14 const char *to_be_replaced, 15 const char *replacement, 16 bool expect_load) 17 { 18 struct changes_pkt_data_freplace *freplace = NULL; 19 struct bpf_program *freplace_prog = NULL; 20 struct bpf_program *main_prog = NULL; 21 LIBBPF_OPTS(bpf_object_open_opts, opts); 22 struct changes_pkt_data *main = NULL; 23 char log[16*1024]; 24 int err; 25 26 opts.kernel_log_buf = log; 27 opts.kernel_log_size = sizeof(log); 28 if (env.verbosity >= VERBOSE_SUPER) 29 opts.kernel_log_level = 1 | 2 | 4; 30 main = changes_pkt_data__open_opts(&opts); 31 if (!ASSERT_OK_PTR(main, "changes_pkt_data__open")) 32 goto out; 33 main_prog = bpf_object__find_program_by_name(main->obj, main_prog_name); 34 if (!ASSERT_OK_PTR(main_prog, "main_prog")) 35 goto out; 36 bpf_program__set_autoload(main_prog, true); 37 err = changes_pkt_data__load(main); 38 print_verifier_log(log); 39 if (!ASSERT_OK(err, "changes_pkt_data__load")) 40 goto out; 41 freplace = changes_pkt_data_freplace__open_opts(&opts); 42 if (!ASSERT_OK_PTR(freplace, "changes_pkt_data_freplace__open")) 43 goto out; 44 freplace_prog = bpf_object__find_program_by_name(freplace->obj, replacement); 45 if (!ASSERT_OK_PTR(freplace_prog, "freplace_prog")) 46 goto out; 47 bpf_program__set_autoload(freplace_prog, true); 48 bpf_program__set_autoattach(freplace_prog, true); 49 bpf_program__set_attach_target(freplace_prog, 50 bpf_program__fd(main_prog), 51 to_be_replaced); 52 err = changes_pkt_data_freplace__load(freplace); 53 print_verifier_log(log); 54 if (expect_load) { 55 ASSERT_OK(err, "changes_pkt_data_freplace__load"); 56 } else { 57 ASSERT_ERR(err, "changes_pkt_data_freplace__load"); 58 ASSERT_HAS_SUBSTR(log, "Extension program changes packet data", "error log"); 59 } 60 61 out: 62 changes_pkt_data_freplace__destroy(freplace); 63 changes_pkt_data__destroy(main); 64 } 65 66 /* There are two global subprograms in both changes_pkt_data.skel.h: 67 * - one changes packet data; 68 * - another does not. 69 * It is ok to freplace subprograms that change packet data with those 70 * that either do or do not. It is only ok to freplace subprograms 71 * that do not change packet data with those that do not as well. 72 * The below tests check outcomes for each combination of such freplace. 73 * Also test a case when main subprogram itself is replaced and is a single 74 * subprogram in a program. 75 */ 76 void test_changes_pkt_data_freplace(void) 77 { 78 struct { 79 const char *main; 80 const char *to_be_replaced; 81 bool changes; 82 } mains[] = { 83 { "main_with_subprogs", "changes_pkt_data", true }, 84 { "main_with_subprogs", "does_not_change_pkt_data", false }, 85 { "main_changes", "main_changes", true }, 86 { "main_does_not_change", "main_does_not_change", false }, 87 }; 88 struct { 89 const char *func; 90 bool changes; 91 } replacements[] = { 92 { "changes_pkt_data", true }, 93 { "does_not_change_pkt_data", false } 94 }; 95 char buf[64]; 96 97 for (int i = 0; i < ARRAY_SIZE(mains); ++i) { 98 for (int j = 0; j < ARRAY_SIZE(replacements); ++j) { 99 snprintf(buf, sizeof(buf), "%s_with_%s", 100 mains[i].to_be_replaced, replacements[j].func); 101 if (!test__start_subtest(buf)) 102 continue; 103 test_aux(mains[i].main, mains[i].to_be_replaced, replacements[j].func, 104 mains[i].changes || !replacements[j].changes); 105 } 106 } 107 } 108