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Diffstat (limited to 'src/test/test-bpf-firewall.c')
-rw-r--r-- | src/test/test-bpf-firewall.c | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/src/test/test-bpf-firewall.c b/src/test/test-bpf-firewall.c new file mode 100644 index 0000000..c4175bc --- /dev/null +++ b/src/test/test-bpf-firewall.c @@ -0,0 +1,217 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <linux/bpf_insn.h> +#include <string.h> +#include <unistd.h> + +#include "bpf-firewall.h" +#include "bpf-program.h" +#include "in-addr-prefix-util.h" +#include "load-fragment.h" +#include "manager.h" +#include "memory-util.h" +#include "rm-rf.h" +#include "service.h" +#include "tests.h" +#include "unit-serialize.h" +#include "virt.h" + +int main(int argc, char *argv[]) { + const struct bpf_insn exit_insn[] = { + BPF_MOV64_IMM(BPF_REG_0, 0), /* drop */ + BPF_EXIT_INSN() + }; + + _cleanup_(rm_rf_physical_and_freep) char *runtime_dir = NULL; + CGroupContext *cc = NULL; + _cleanup_(bpf_program_freep) BPFProgram *p = NULL; + _cleanup_(manager_freep) Manager *m = NULL; + Unit *u; + char log_buf[65535]; + struct rlimit rl; + int r; + union bpf_attr attr; + bool test_custom_filter = false; + const char *test_prog = "/sys/fs/bpf/test-dropper"; + + test_setup_logging(LOG_DEBUG); + + if (detect_container() > 0) + return log_tests_skipped("test-bpf-firewall fails inside LXC and Docker containers: https://github.com/systemd/systemd/issues/9666"); + + assert_se(getrlimit(RLIMIT_MEMLOCK, &rl) >= 0); + rl.rlim_cur = rl.rlim_max = MAX(rl.rlim_max, CAN_MEMLOCK_SIZE); + (void) setrlimit(RLIMIT_MEMLOCK, &rl); + + if (!can_memlock()) + return log_tests_skipped("Can't use mlock()"); + + r = enter_cgroup_subroot(NULL); + if (r == -ENOMEDIUM) + return log_tests_skipped("cgroupfs not available"); + + _cleanup_free_ char *unit_dir = NULL; + assert_se(get_testdata_dir("units", &unit_dir) >= 0); + assert_se(set_unit_path(unit_dir) >= 0); + assert_se(runtime_dir = setup_fake_runtime_dir()); + + r = bpf_program_new(BPF_PROG_TYPE_CGROUP_SKB, "sd_trivial", &p); + assert_se(r == 0); + + r = bpf_program_add_instructions(p, exit_insn, ELEMENTSOF(exit_insn)); + assert_se(r == 0); + + r = bpf_firewall_supported(); + if (r == BPF_FIREWALL_UNSUPPORTED) + return log_tests_skipped("BPF firewalling not supported"); + assert_se(r > 0); + + if (r == BPF_FIREWALL_SUPPORTED_WITH_MULTI) { + log_notice("BPF firewalling with BPF_F_ALLOW_MULTI supported. Yay!"); + test_custom_filter = true; + } else + log_notice("BPF firewalling (though without BPF_F_ALLOW_MULTI) supported. Good."); + + r = bpf_program_load_kernel(p, log_buf, ELEMENTSOF(log_buf)); + assert_se(r >= 0); + + if (test_custom_filter) { + zero(attr); + attr.pathname = PTR_TO_UINT64(test_prog); + attr.bpf_fd = p->kernel_fd; + attr.file_flags = 0; + + (void) unlink(test_prog); + + r = bpf(BPF_OBJ_PIN, &attr, sizeof(attr)); + if (r < 0) { + log_warning_errno(errno, "BPF object pinning failed, will not run custom filter test: %m"); + test_custom_filter = false; + } + } + + p = bpf_program_free(p); + + /* The simple tests succeeded. Now let's try full unit-based use-case. */ + + assert_se(manager_new(RUNTIME_SCOPE_USER, MANAGER_TEST_RUN_BASIC, &m) >= 0); + assert_se(manager_startup(m, NULL, NULL, NULL) >= 0); + + assert_se(u = unit_new(m, sizeof(Service))); + assert_se(unit_add_name(u, "foo.service") == 0); + assert_se(cc = unit_get_cgroup_context(u)); + u->perpetual = true; + + cc->ip_accounting = true; + + assert_se(config_parse_in_addr_prefixes(u->id, "filename", 1, "Service", 1, "IPAddressAllow", 0, "10.0.1.0/24", &cc->ip_address_allow, NULL) == 0); + assert_se(config_parse_in_addr_prefixes(u->id, "filename", 1, "Service", 1, "IPAddressAllow", 0, "127.0.0.2", &cc->ip_address_allow, NULL) == 0); + assert_se(config_parse_in_addr_prefixes(u->id, "filename", 1, "Service", 1, "IPAddressDeny", 0, "127.0.0.3", &cc->ip_address_deny, NULL) == 0); + assert_se(config_parse_in_addr_prefixes(u->id, "filename", 1, "Service", 1, "IPAddressDeny", 0, "10.0.3.2/24", &cc->ip_address_deny, NULL) == 0); + assert_se(config_parse_in_addr_prefixes(u->id, "filename", 1, "Service", 1, "IPAddressDeny", 0, "127.0.0.1/25", &cc->ip_address_deny, NULL) == 0); + assert_se(config_parse_in_addr_prefixes(u->id, "filename", 1, "Service", 1, "IPAddressDeny", 0, "127.0.0.4", &cc->ip_address_deny, NULL) == 0); + + assert_se(set_size(cc->ip_address_allow) == 2); + assert_se(set_size(cc->ip_address_deny) == 4); + + /* The deny list is defined redundantly, let's ensure it will be properly reduced */ + assert_se(in_addr_prefixes_reduce(cc->ip_address_allow) >= 0); + assert_se(in_addr_prefixes_reduce(cc->ip_address_deny) >= 0); + + assert_se(set_size(cc->ip_address_allow) == 2); + assert_se(set_size(cc->ip_address_deny) == 2); + + assert_se(set_contains(cc->ip_address_allow, &(struct in_addr_prefix) { + .family = AF_INET, + .address.in.s_addr = htobe32((UINT32_C(10) << 24) | (UINT32_C(1) << 8)), + .prefixlen = 24 })); + assert_se(set_contains(cc->ip_address_allow, &(struct in_addr_prefix) { + .family = AF_INET, + .address.in.s_addr = htobe32(0x7f000002), + .prefixlen = 32 })); + assert_se(set_contains(cc->ip_address_deny, &(struct in_addr_prefix) { + .family = AF_INET, + .address.in.s_addr = htobe32(0x7f000000), + .prefixlen = 25 })); + assert_se(set_contains(cc->ip_address_deny, &(struct in_addr_prefix) { + .family = AF_INET, + .address.in.s_addr = htobe32((UINT32_C(10) << 24) | (UINT32_C(3) << 8)), + .prefixlen = 24 })); + + assert_se(config_parse_exec(u->id, "filename", 1, "Service", 1, "ExecStart", SERVICE_EXEC_START, "/bin/ping -c 1 127.0.0.2 -W 5", SERVICE(u)->exec_command, u) == 0); + assert_se(config_parse_exec(u->id, "filename", 1, "Service", 1, "ExecStart", SERVICE_EXEC_START, "/bin/ping -c 1 127.0.0.3 -W 5", SERVICE(u)->exec_command, u) == 0); + + assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]); + assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]->command_next); + assert_se(!SERVICE(u)->exec_command[SERVICE_EXEC_START]->command_next->command_next); + + SERVICE(u)->type = SERVICE_ONESHOT; + u->load_state = UNIT_LOADED; + + unit_dump(u, stdout, NULL); + + r = bpf_firewall_compile(u); + if (IN_SET(r, -ENOTTY, -ENOSYS, -EPERM)) + return log_tests_skipped("Kernel doesn't support the necessary bpf bits (masked out via seccomp?)"); + assert_se(r >= 0); + + assert_se(u->ip_bpf_ingress); + assert_se(u->ip_bpf_egress); + + r = bpf_program_load_kernel(u->ip_bpf_ingress, log_buf, ELEMENTSOF(log_buf)); + + log_notice("log:"); + log_notice("-------"); + log_notice("%s", log_buf); + log_notice("-------"); + + assert_se(r >= 0); + + r = bpf_program_load_kernel(u->ip_bpf_egress, log_buf, ELEMENTSOF(log_buf)); + + log_notice("log:"); + log_notice("-------"); + log_notice("%s", log_buf); + log_notice("-------"); + + assert_se(r >= 0); + + assert_se(unit_start(u, NULL) >= 0); + + while (!IN_SET(SERVICE(u)->state, SERVICE_DEAD, SERVICE_FAILED)) + assert_se(sd_event_run(m->event, UINT64_MAX) >= 0); + + assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]->exec_status.code == CLD_EXITED && + SERVICE(u)->exec_command[SERVICE_EXEC_START]->exec_status.status == EXIT_SUCCESS); + + assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]->command_next->exec_status.code != CLD_EXITED || + SERVICE(u)->exec_command[SERVICE_EXEC_START]->command_next->exec_status.status != EXIT_SUCCESS); + + if (test_custom_filter) { + assert_se(u = unit_new(m, sizeof(Service))); + assert_se(unit_add_name(u, "custom-filter.service") == 0); + assert_se(cc = unit_get_cgroup_context(u)); + u->perpetual = true; + + cc->ip_accounting = true; + + assert_se(config_parse_ip_filter_bpf_progs(u->id, "filename", 1, "Service", 1, "IPIngressFilterPath", 0, test_prog, &cc->ip_filters_ingress, u) == 0); + assert_se(config_parse_exec(u->id, "filename", 1, "Service", 1, "ExecStart", SERVICE_EXEC_START, "-/bin/ping -c 1 127.0.0.1 -W 5", SERVICE(u)->exec_command, u) == 0); + + SERVICE(u)->type = SERVICE_ONESHOT; + u->load_state = UNIT_LOADED; + + assert_se(unit_start(u, NULL) >= 0); + + while (!IN_SET(SERVICE(u)->state, SERVICE_DEAD, SERVICE_FAILED)) + assert_se(sd_event_run(m->event, UINT64_MAX) >= 0); + + assert_se(SERVICE(u)->exec_command[SERVICE_EXEC_START]->exec_status.code != CLD_EXITED || + SERVICE(u)->exec_command[SERVICE_EXEC_START]->exec_status.status != EXIT_SUCCESS); + + (void) unlink(test_prog); + assert_se(SERVICE(u)->state == SERVICE_DEAD); + } + + return 0; +} |