test: (mkfds::bpf-link) new factory

Signed-off-by: WanBingjiang <wanbingjiang@webray.com.cn>

diff --git a/meson.build b/meson.build
index 5f556ebced140e24f0c67b48d4e04d915521f3ff..dfdf085176063527d8b329a60b1bf0373f66c275 100644 (file)
--- a/meson.build
+++ b/meson.build
@@ -4060,6 +4060,10 @@ if not is_disabler(exe)
 endif
 
 if LINUX and lib_rt.found()
+  test_mkfds_c_args = []
+  if cc.has_header_symbol('linux/bpf.h', 'BPF_LINK_CREATE')
+    test_mkfds_c_args += ['-DHAVE_BPF_LINK_CREATE']
+  endif
   exe = executable(
     'test_mkfds',
     'tests/helpers/test_mkfds.c',
@@ -4067,6 +4071,7 @@ if LINUX and lib_rt.found()
     'tests/helpers/test_mkfds_ppoll.c',
     include_directories : includes,
     dependencies : [lib_rt],
+    c_args : test_mkfds_c_args,
     build_by_default: program_tests)
   exes += exe
 endif

diff --git a/tests/helpers/test_mkfds.c b/tests/helpers/test_mkfds.c
index 093ac06c61005afb9f6adbf69ff586681f2411cd..a8ee45129370f112002a096bf00f7ba22b8adc94 100644 (file)
--- a/tests/helpers/test_mkfds.c
+++ b/tests/helpers/test_mkfds.c
@@ -3001,6 +3001,100 @@ static void *make_bpf_map(const struct factory *factory, struct fdesc fdescs[],
        return NULL;
 }
 
+#ifdef HAVE_BPF_LINK_CREATE
+static void *make_bpf_link(const struct factory *factory _U_, struct fdesc fdescs[],
+                               int argc _U_, char ** argv _U_)
+{
+       int prog_fd, link_fd, cgroup_fd;
+       union bpf_attr attr;
+       struct bpf_link_info info = {};
+       /* Just doing exit with 1 (SK_PASS). */
+       struct bpf_insn insns[] = {
+               [0] = {
+                       .code  = BPF_ALU64 | BPF_MOV | BPF_K,
+                       .dst_reg = BPF_REG_0, .src_reg = 0, .off   = 0, .imm   = 1
+               },
+               [1] = {
+                       .code  = BPF_JMP | BPF_EXIT,
+                       .dst_reg = 0, .src_reg = 0, .off   = 0, .imm   = 0
+               },
+       };
+
+       memset(&attr, 0, sizeof(attr));
+       attr.prog_type = BPF_PROG_TYPE_CGROUP_SKB;
+       attr.insns = (uint64_t)(unsigned long)insns;
+       attr.insn_cnt = ARRAY_SIZE(insns);
+       attr.license = (int64_t)(unsigned long)"GPL";
+       prog_fd = syscall(SYS_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
+       if (prog_fd < 0)
+               err_nosys(EXIT_FAILURE, "failed in bpf(BPF_PROG_LOAD)");
+
+       cgroup_fd = open("/sys/fs/cgroup", O_RDONLY | O_DIRECTORY);
+       if (cgroup_fd < 0)
+               err_nosys(EXIT_FAILURE, "failed in open(/sys/fs/cgroup)");
+
+       memset(&attr, 0, sizeof(attr));
+       attr.link_create.prog_fd = prog_fd;
+       attr.link_create.target_fd = cgroup_fd;
+       attr.link_create.attach_type = BPF_CGROUP_INET_INGRESS;
+       link_fd = syscall(SYS_bpf, BPF_LINK_CREATE, &attr, sizeof(attr));
+       if (link_fd < 0) {
+               close(cgroup_fd);
+               close(prog_fd);
+               err_nosys(EXIT_FAILURE, "failed in bpf(BPF_LINK_CREATE)");
+       }
+
+       close(prog_fd);
+       close(cgroup_fd);
+
+       if (link_fd != fdescs[0].fd) {
+               if (dup2(link_fd, fdescs[0].fd) < 0)
+                       err(EXIT_FAILURE, "failed to dup %d -> %d", link_fd, fdescs[0].fd);
+               close(link_fd);
+       }
+
+       memset(&attr, 0, sizeof(attr));
+       attr.info.bpf_fd = fdescs[0].fd;
+       attr.info.info_len = sizeof(info);
+       attr.info.info = (uint64_t)(unsigned long)&info;
+       if (syscall(SYS_bpf, BPF_OBJ_GET_INFO_BY_FD, &attr, sizeof(attr)) < 0)
+               err_nosys(EXIT_FAILURE, "failed in bpf(BPF_OBJ_GET_INFO_BY_FD)");
+
+       fdescs[0] = (struct fdesc){
+               .fd    = fdescs[0].fd,
+               .close = close_fdesc,
+               .data  = NULL
+       };
+
+       return xmemdup(&info, sizeof(info));
+}
+
+enum ritem_bpf_link {
+       RITEM_BPF_LINK_ID,
+       RITEM_BPF_LINK_PROG_ID,
+};
+
+static void report_bpf_link(const struct factory *factory _U_,
+                               int nth, void *data, FILE *fp)
+{
+       struct bpf_link_info *info = data;
+
+       switch (nth) {
+       case RITEM_BPF_LINK_ID:
+               fprintf(fp, "%u", info->id);
+               break;
+       case RITEM_BPF_LINK_PROG_ID:
+               fprintf(fp, "%u", info->prog_id);
+               break;
+       }
+}
+
+static void free_bpf_link(const struct factory * factory _U_, void *data)
+{
+       free(data);
+}
+#endif /* HAVE_BPF_LINK_CREATE */
+
 static void *make_pty(const struct factory *factory _U_, struct fdesc fdescs[],
                      int argc _U_, char ** argv _U_)
 {
@@ -4309,6 +4403,26 @@ static const struct factory factories[] = {
                        PARAM_END
                }
        },
+#ifdef HAVE_BPF_LINK_CREATE
+       {
+               .name = "bpf-link",
+               .desc = "make bpf-link",
+               .priv = true,
+               .N    = 1,
+               .EX_N = 0,
+               .EX_O = 2,
+               .make = make_bpf_link,
+               .report = report_bpf_link,
+               .free = free_bpf_link,
+               .params = (struct parameter []) {
+                       PARAM_END
+               },
+               .o_descs = (const char *[]) {
+                       [RITEM_BPF_LINK_ID]  = "the id of bpf link object",
+                       [RITEM_BPF_LINK_PROG_ID] = "the id of bpf prog attached by the link",
+               },
+       },
+#endif
        {
                .name = "pty",
                .desc = "make a pair of ptmx and pts",