From 65b4414a05ebf51966c4a28a2a1b156ab5a01b0f Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Thu, 27 Jun 2019 13:38:53 -0700 Subject: [PATCH] selftests/bpf: add sockopt test that exercises BPF_F_ALLOW_MULTI sockopt test that verifies chaining behavior. v9: * setsockopt chaining example v7: * rework the test to verify cgroup getsockopt chaining Cc: Andrii Nakryiko Cc: Martin Lau Signed-off-by: Stanislav Fomichev Signed-off-by: Alexei Starovoitov --- tools/testing/selftests/bpf/.gitignore | 1 + tools/testing/selftests/bpf/Makefile | 4 +- tools/testing/selftests/bpf/progs/sockopt_multi.c | 71 ++++ tools/testing/selftests/bpf/test_sockopt_multi.c | 374 ++++++++++++++++++++++ 4 files changed, 449 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/progs/sockopt_multi.c create mode 100644 tools/testing/selftests/bpf/test_sockopt_multi.c diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore index 8ac076c..a2f7f79 100644 --- a/tools/testing/selftests/bpf/.gitignore +++ b/tools/testing/selftests/bpf/.gitignore @@ -41,3 +41,4 @@ test_btf_dump xdping test_sockopt test_sockopt_sk +test_sockopt_multi diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 57ae4e1..de1754a 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -26,7 +26,8 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test test_sock test_btf test_sockmap get_cgroup_id_user test_socket_cookie \ test_cgroup_storage test_select_reuseport test_section_names \ test_netcnt test_tcpnotify_user test_sock_fields test_sysctl test_hashmap \ - test_btf_dump test_cgroup_attach xdping test_sockopt test_sockopt_sk + test_btf_dump test_cgroup_attach xdping test_sockopt test_sockopt_sk \ + test_sockopt_multi BPF_OBJ_FILES = $(patsubst %.c,%.o, $(notdir $(wildcard progs/*.c))) TEST_GEN_FILES = $(BPF_OBJ_FILES) @@ -105,6 +106,7 @@ $(OUTPUT)/test_sysctl: cgroup_helpers.c $(OUTPUT)/test_cgroup_attach: cgroup_helpers.c $(OUTPUT)/test_sockopt: cgroup_helpers.c $(OUTPUT)/test_sockopt_sk: cgroup_helpers.c +$(OUTPUT)/test_sockopt_multi: cgroup_helpers.c .PHONY: force diff --git a/tools/testing/selftests/bpf/progs/sockopt_multi.c b/tools/testing/selftests/bpf/progs/sockopt_multi.c new file mode 100644 index 0000000..4afd259 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/sockopt_multi.c @@ -0,0 +1,71 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include "bpf_helpers.h" + +char _license[] SEC("license") = "GPL"; +__u32 _version SEC("version") = 1; + +SEC("cgroup/getsockopt/child") +int _getsockopt_child(struct bpf_sockopt *ctx) +{ + __u8 *optval_end = ctx->optval_end; + __u8 *optval = ctx->optval; + + if (ctx->level != SOL_IP || ctx->optname != IP_TOS) + return 1; + + if (optval + 1 > optval_end) + return 0; /* EPERM, bounds check */ + + if (optval[0] != 0x80) + return 0; /* EPERM, unexpected optval from the kernel */ + + ctx->retval = 0; /* Reset system call return value to zero */ + + optval[0] = 0x90; + ctx->optlen = 1; + + return 1; +} + +SEC("cgroup/getsockopt/parent") +int _getsockopt_parent(struct bpf_sockopt *ctx) +{ + __u8 *optval_end = ctx->optval_end; + __u8 *optval = ctx->optval; + + if (ctx->level != SOL_IP || ctx->optname != IP_TOS) + return 1; + + if (optval + 1 > optval_end) + return 0; /* EPERM, bounds check */ + + if (optval[0] != 0x90) + return 0; /* EPERM, unexpected optval from the kernel */ + + ctx->retval = 0; /* Reset system call return value to zero */ + + optval[0] = 0xA0; + ctx->optlen = 1; + + return 1; +} + +SEC("cgroup/setsockopt") +int _setsockopt(struct bpf_sockopt *ctx) +{ + __u8 *optval_end = ctx->optval_end; + __u8 *optval = ctx->optval; + + if (ctx->level != SOL_IP || ctx->optname != IP_TOS) + return 1; + + if (optval + 1 > optval_end) + return 0; /* EPERM, bounds check */ + + optval[0] += 0x10; + ctx->optlen = 1; + + return 1; +} diff --git a/tools/testing/selftests/bpf/test_sockopt_multi.c b/tools/testing/selftests/bpf/test_sockopt_multi.c new file mode 100644 index 0000000..4be3441 --- /dev/null +++ b/tools/testing/selftests/bpf/test_sockopt_multi.c @@ -0,0 +1,374 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include "bpf_rlimit.h" +#include "bpf_util.h" +#include "cgroup_helpers.h" + +static int prog_attach(struct bpf_object *obj, int cgroup_fd, const char *title) +{ + enum bpf_attach_type attach_type; + enum bpf_prog_type prog_type; + struct bpf_program *prog; + int err; + + err = libbpf_prog_type_by_name(title, &prog_type, &attach_type); + if (err) { + log_err("Failed to deduct types for %s BPF program", title); + return -1; + } + + prog = bpf_object__find_program_by_title(obj, title); + if (!prog) { + log_err("Failed to find %s BPF program", title); + return -1; + } + + err = bpf_prog_attach(bpf_program__fd(prog), cgroup_fd, + attach_type, BPF_F_ALLOW_MULTI); + if (err) { + log_err("Failed to attach %s BPF program", title); + return -1; + } + + return 0; +} + +static int prog_detach(struct bpf_object *obj, int cgroup_fd, const char *title) +{ + enum bpf_attach_type attach_type; + enum bpf_prog_type prog_type; + struct bpf_program *prog; + int err; + + err = libbpf_prog_type_by_name(title, &prog_type, &attach_type); + if (err) + return -1; + + prog = bpf_object__find_program_by_title(obj, title); + if (!prog) + return -1; + + err = bpf_prog_detach2(bpf_program__fd(prog), cgroup_fd, + attach_type); + if (err) + return -1; + + return 0; +} + +static int run_getsockopt_test(struct bpf_object *obj, int cg_parent, + int cg_child, int sock_fd) +{ + socklen_t optlen; + __u8 buf; + int err; + + /* Set IP_TOS to the expected value (0x80). */ + + buf = 0x80; + err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1); + if (err < 0) { + log_err("Failed to call setsockopt(IP_TOS)"); + goto detach; + } + + buf = 0x00; + optlen = 1; + err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen); + if (err) { + log_err("Failed to call getsockopt(IP_TOS)"); + goto detach; + } + + if (buf != 0x80) { + log_err("Unexpected getsockopt 0x%x != 0x80 without BPF", buf); + err = -1; + goto detach; + } + + /* Attach child program and make sure it returns new value: + * - kernel: -> 0x80 + * - child: 0x80 -> 0x90 + */ + + err = prog_attach(obj, cg_child, "cgroup/getsockopt/child"); + if (err) + goto detach; + + buf = 0x00; + optlen = 1; + err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen); + if (err) { + log_err("Failed to call getsockopt(IP_TOS)"); + goto detach; + } + + if (buf != 0x90) { + log_err("Unexpected getsockopt 0x%x != 0x90", buf); + err = -1; + goto detach; + } + + /* Attach parent program and make sure it returns new value: + * - kernel: -> 0x80 + * - child: 0x80 -> 0x90 + * - parent: 0x90 -> 0xA0 + */ + + err = prog_attach(obj, cg_parent, "cgroup/getsockopt/parent"); + if (err) + goto detach; + + buf = 0x00; + optlen = 1; + err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen); + if (err) { + log_err("Failed to call getsockopt(IP_TOS)"); + goto detach; + } + + if (buf != 0xA0) { + log_err("Unexpected getsockopt 0x%x != 0xA0", buf); + err = -1; + goto detach; + } + + /* Setting unexpected initial sockopt should return EPERM: + * - kernel: -> 0x40 + * - child: unexpected 0x40, EPERM + * - parent: unexpected 0x40, EPERM + */ + + buf = 0x40; + if (setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1) < 0) { + log_err("Failed to call setsockopt(IP_TOS)"); + goto detach; + } + + buf = 0x00; + optlen = 1; + err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen); + if (!err) { + log_err("Unexpected success from getsockopt(IP_TOS)"); + goto detach; + } + + /* Detach child program and make sure we still get EPERM: + * - kernel: -> 0x40 + * - parent: unexpected 0x40, EPERM + */ + + err = prog_detach(obj, cg_child, "cgroup/getsockopt/child"); + if (err) { + log_err("Failed to detach child program"); + goto detach; + } + + buf = 0x00; + optlen = 1; + err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen); + if (!err) { + log_err("Unexpected success from getsockopt(IP_TOS)"); + goto detach; + } + + /* Set initial value to the one the parent program expects: + * - kernel: -> 0x90 + * - parent: 0x90 -> 0xA0 + */ + + buf = 0x90; + err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1); + if (err < 0) { + log_err("Failed to call setsockopt(IP_TOS)"); + goto detach; + } + + buf = 0x00; + optlen = 1; + err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen); + if (err) { + log_err("Failed to call getsockopt(IP_TOS)"); + goto detach; + } + + if (buf != 0xA0) { + log_err("Unexpected getsockopt 0x%x != 0xA0", buf); + err = -1; + goto detach; + } + +detach: + prog_detach(obj, cg_child, "cgroup/getsockopt/child"); + prog_detach(obj, cg_parent, "cgroup/getsockopt/parent"); + + return err; +} + +static int run_setsockopt_test(struct bpf_object *obj, int cg_parent, + int cg_child, int sock_fd) +{ + socklen_t optlen; + __u8 buf; + int err; + + /* Set IP_TOS to the expected value (0x80). */ + + buf = 0x80; + err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1); + if (err < 0) { + log_err("Failed to call setsockopt(IP_TOS)"); + goto detach; + } + + buf = 0x00; + optlen = 1; + err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen); + if (err) { + log_err("Failed to call getsockopt(IP_TOS)"); + goto detach; + } + + if (buf != 0x80) { + log_err("Unexpected getsockopt 0x%x != 0x80 without BPF", buf); + err = -1; + goto detach; + } + + /* Attach child program and make sure it adds 0x10. */ + + err = prog_attach(obj, cg_child, "cgroup/setsockopt"); + if (err) + goto detach; + + buf = 0x80; + err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1); + if (err < 0) { + log_err("Failed to call setsockopt(IP_TOS)"); + goto detach; + } + + buf = 0x00; + optlen = 1; + err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen); + if (err) { + log_err("Failed to call getsockopt(IP_TOS)"); + goto detach; + } + + if (buf != 0x80 + 0x10) { + log_err("Unexpected getsockopt 0x%x != 0x80 + 0x10", buf); + err = -1; + goto detach; + } + + /* Attach parent program and make sure it adds another 0x10. */ + + err = prog_attach(obj, cg_parent, "cgroup/setsockopt"); + if (err) + goto detach; + + buf = 0x80; + err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1); + if (err < 0) { + log_err("Failed to call setsockopt(IP_TOS)"); + goto detach; + } + + buf = 0x00; + optlen = 1; + err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen); + if (err) { + log_err("Failed to call getsockopt(IP_TOS)"); + goto detach; + } + + if (buf != 0x80 + 2 * 0x10) { + log_err("Unexpected getsockopt 0x%x != 0x80 + 2 * 0x10", buf); + err = -1; + goto detach; + } + +detach: + prog_detach(obj, cg_child, "cgroup/setsockopt"); + prog_detach(obj, cg_parent, "cgroup/setsockopt"); + + return err; +} + +int main(int argc, char **argv) +{ + struct bpf_prog_load_attr attr = { + .file = "./sockopt_multi.o", + }; + int cg_parent = -1, cg_child = -1; + struct bpf_object *obj = NULL; + int sock_fd = -1; + int err = -1; + int ignored; + + if (setup_cgroup_environment()) { + log_err("Failed to setup cgroup environment\n"); + goto out; + } + + cg_parent = create_and_get_cgroup("/parent"); + if (cg_parent < 0) { + log_err("Failed to create cgroup /parent\n"); + goto out; + } + + cg_child = create_and_get_cgroup("/parent/child"); + if (cg_child < 0) { + log_err("Failed to create cgroup /parent/child\n"); + goto out; + } + + if (join_cgroup("/parent/child")) { + log_err("Failed to join cgroup /parent/child\n"); + goto out; + } + + err = bpf_prog_load_xattr(&attr, &obj, &ignored); + if (err) { + log_err("Failed to load BPF object"); + goto out; + } + + sock_fd = socket(AF_INET, SOCK_STREAM, 0); + if (sock_fd < 0) { + log_err("Failed to create socket"); + goto out; + } + + if (run_getsockopt_test(obj, cg_parent, cg_child, sock_fd)) + err = -1; + printf("test_sockopt_multi: getsockopt %s\n", + err ? "FAILED" : "PASSED"); + + if (run_setsockopt_test(obj, cg_parent, cg_child, sock_fd)) + err = -1; + printf("test_sockopt_multi: setsockopt %s\n", + err ? "FAILED" : "PASSED"); + +out: + close(sock_fd); + bpf_object__close(obj); + close(cg_child); + close(cg_parent); + + printf("test_sockopt_multi: %s\n", err ? "FAILED" : "PASSED"); + return err ? EXIT_FAILURE : EXIT_SUCCESS; +} -- 2.7.4