diff options
Diffstat (limited to 'samples/bpf/test_cgrp2_attach2.c')
| -rw-r--r-- | samples/bpf/test_cgrp2_attach2.c | 442 |
1 files changed, 442 insertions, 0 deletions
diff --git a/samples/bpf/test_cgrp2_attach2.c b/samples/bpf/test_cgrp2_attach2.c new file mode 100644 index 000000000..180f9d813 --- /dev/null +++ b/samples/bpf/test_cgrp2_attach2.c @@ -0,0 +1,442 @@ +/* eBPF example program: + * + * - Creates arraymap in kernel with 4 bytes keys and 8 byte values + * + * - Loads eBPF program + * + * The eBPF program accesses the map passed in to store two pieces of + * information. The number of invocations of the program, which maps + * to the number of packets received, is stored to key 0. Key 1 is + * incremented on each iteration by the number of bytes stored in + * the skb. The program also stores the number of received bytes + * in the cgroup storage. + * + * - Attaches the new program to a cgroup using BPF_PROG_ATTACH + * + * - Every second, reads map[0] and map[1] to see how many bytes and + * packets were seen on any socket of tasks in the given cgroup. + */ + +#define _GNU_SOURCE + +#include <stdio.h> +#include <stdlib.h> +#include <assert.h> +#include <sys/resource.h> +#include <sys/time.h> +#include <unistd.h> + +#include <linux/bpf.h> +#include <bpf/bpf.h> + +#include "bpf_insn.h" +#include "bpf_rlimit.h" +#include "cgroup_helpers.h" + +#define FOO "/foo" +#define BAR "/foo/bar/" +#define PING_CMD "ping -c1 -w1 127.0.0.1 > /dev/null" + +char bpf_log_buf[BPF_LOG_BUF_SIZE]; + +static int prog_load(int verdict) +{ + int ret; + struct bpf_insn prog[] = { + BPF_MOV64_IMM(BPF_REG_0, verdict), /* r0 = verdict */ + BPF_EXIT_INSN(), + }; + size_t insns_cnt = sizeof(prog) / sizeof(struct bpf_insn); + + ret = bpf_load_program(BPF_PROG_TYPE_CGROUP_SKB, + prog, insns_cnt, "GPL", 0, + bpf_log_buf, BPF_LOG_BUF_SIZE); + + if (ret < 0) { + log_err("Loading program"); + printf("Output from verifier:\n%s\n-------\n", bpf_log_buf); + return 0; + } + return ret; +} + +static int test_foo_bar(void) +{ + int drop_prog, allow_prog, foo = 0, bar = 0, rc = 0; + + allow_prog = prog_load(1); + if (!allow_prog) + goto err; + + drop_prog = prog_load(0); + if (!drop_prog) + goto err; + + if (setup_cgroup_environment()) + goto err; + + /* Create cgroup /foo, get fd, and join it */ + foo = create_and_get_cgroup(FOO); + if (!foo) + goto err; + + if (join_cgroup(FOO)) + goto err; + + if (bpf_prog_attach(drop_prog, foo, BPF_CGROUP_INET_EGRESS, + BPF_F_ALLOW_OVERRIDE)) { + log_err("Attaching prog to /foo"); + goto err; + } + + printf("Attached DROP prog. This ping in cgroup /foo should fail...\n"); + assert(system(PING_CMD) != 0); + + /* Create cgroup /foo/bar, get fd, and join it */ + bar = create_and_get_cgroup(BAR); + if (!bar) + goto err; + + if (join_cgroup(BAR)) + goto err; + + printf("Attached DROP prog. This ping in cgroup /foo/bar should fail...\n"); + assert(system(PING_CMD) != 0); + + if (bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS, + BPF_F_ALLOW_OVERRIDE)) { + log_err("Attaching prog to /foo/bar"); + goto err; + } + + printf("Attached PASS prog. This ping in cgroup /foo/bar should pass...\n"); + assert(system(PING_CMD) == 0); + + if (bpf_prog_detach(bar, BPF_CGROUP_INET_EGRESS)) { + log_err("Detaching program from /foo/bar"); + goto err; + } + + printf("Detached PASS from /foo/bar while DROP is attached to /foo.\n" + "This ping in cgroup /foo/bar should fail...\n"); + assert(system(PING_CMD) != 0); + + if (bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS, + BPF_F_ALLOW_OVERRIDE)) { + log_err("Attaching prog to /foo/bar"); + goto err; + } + + if (bpf_prog_detach(foo, BPF_CGROUP_INET_EGRESS)) { + log_err("Detaching program from /foo"); + goto err; + } + + printf("Attached PASS from /foo/bar and detached DROP from /foo.\n" + "This ping in cgroup /foo/bar should pass...\n"); + assert(system(PING_CMD) == 0); + + if (bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS, + BPF_F_ALLOW_OVERRIDE)) { + log_err("Attaching prog to /foo/bar"); + goto err; + } + + if (!bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS, 0)) { + errno = 0; + log_err("Unexpected success attaching prog to /foo/bar"); + goto err; + } + + if (bpf_prog_detach(bar, BPF_CGROUP_INET_EGRESS)) { + log_err("Detaching program from /foo/bar"); + goto err; + } + + if (!bpf_prog_detach(foo, BPF_CGROUP_INET_EGRESS)) { + errno = 0; + log_err("Unexpected success in double detach from /foo"); + goto err; + } + + if (bpf_prog_attach(allow_prog, foo, BPF_CGROUP_INET_EGRESS, 0)) { + log_err("Attaching non-overridable prog to /foo"); + goto err; + } + + if (!bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS, 0)) { + errno = 0; + log_err("Unexpected success attaching non-overridable prog to /foo/bar"); + goto err; + } + + if (!bpf_prog_attach(allow_prog, bar, BPF_CGROUP_INET_EGRESS, + BPF_F_ALLOW_OVERRIDE)) { + errno = 0; + log_err("Unexpected success attaching overridable prog to /foo/bar"); + goto err; + } + + if (!bpf_prog_attach(allow_prog, foo, BPF_CGROUP_INET_EGRESS, + BPF_F_ALLOW_OVERRIDE)) { + errno = 0; + log_err("Unexpected success attaching overridable prog to /foo"); + goto err; + } + + if (bpf_prog_attach(drop_prog, foo, BPF_CGROUP_INET_EGRESS, 0)) { + log_err("Attaching different non-overridable prog to /foo"); + goto err; + } + + goto out; + +err: + rc = 1; + +out: + close(foo); + close(bar); + cleanup_cgroup_environment(); + if (!rc) + printf("### override:PASS\n"); + else + printf("### override:FAIL\n"); + return rc; +} + +static int map_fd = -1; + +static int prog_load_cnt(int verdict, int val) +{ + int cgroup_storage_fd; + + if (map_fd < 0) + map_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, 4, 8, 1, 0); + if (map_fd < 0) { + printf("failed to create map '%s'\n", strerror(errno)); + return -1; + } + + cgroup_storage_fd = bpf_create_map(BPF_MAP_TYPE_CGROUP_STORAGE, + sizeof(struct bpf_cgroup_storage_key), 8, 0, 0); + if (cgroup_storage_fd < 0) { + printf("failed to create map '%s'\n", strerror(errno)); + return -1; + } + + struct bpf_insn prog[] = { + BPF_MOV32_IMM(BPF_REG_0, 0), + BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_0, -4), /* *(u32 *)(fp - 4) = r0 */ + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4), /* r2 = fp - 4 */ + BPF_LD_MAP_FD(BPF_REG_1, map_fd), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2), + BPF_MOV64_IMM(BPF_REG_1, val), /* r1 = 1 */ + BPF_RAW_INSN(BPF_STX | BPF_XADD | BPF_DW, BPF_REG_0, BPF_REG_1, 0, 0), /* xadd r0 += r1 */ + BPF_LD_MAP_FD(BPF_REG_1, cgroup_storage_fd), + BPF_MOV64_IMM(BPF_REG_2, 0), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_local_storage), + BPF_MOV64_IMM(BPF_REG_1, val), + BPF_RAW_INSN(BPF_STX | BPF_XADD | BPF_W, BPF_REG_0, BPF_REG_1, 0, 0), + BPF_MOV64_IMM(BPF_REG_0, verdict), /* r0 = verdict */ + BPF_EXIT_INSN(), + }; + size_t insns_cnt = sizeof(prog) / sizeof(struct bpf_insn); + int ret; + + ret = bpf_load_program(BPF_PROG_TYPE_CGROUP_SKB, + prog, insns_cnt, "GPL", 0, + bpf_log_buf, BPF_LOG_BUF_SIZE); + + if (ret < 0) { + log_err("Loading program"); + printf("Output from verifier:\n%s\n-------\n", bpf_log_buf); + return 0; + } + close(cgroup_storage_fd); + return ret; +} + + +static int test_multiprog(void) +{ + __u32 prog_ids[4], prog_cnt = 0, attach_flags, saved_prog_id; + int cg1 = 0, cg2 = 0, cg3 = 0, cg4 = 0, cg5 = 0, key = 0; + int drop_prog, allow_prog[6] = {}, rc = 0; + unsigned long long value; + int i = 0; + + for (i = 0; i < 6; i++) { + allow_prog[i] = prog_load_cnt(1, 1 << i); + if (!allow_prog[i]) + goto err; + } + drop_prog = prog_load_cnt(0, 1); + if (!drop_prog) + goto err; + + if (setup_cgroup_environment()) + goto err; + + cg1 = create_and_get_cgroup("/cg1"); + if (!cg1) + goto err; + cg2 = create_and_get_cgroup("/cg1/cg2"); + if (!cg2) + goto err; + cg3 = create_and_get_cgroup("/cg1/cg2/cg3"); + if (!cg3) + goto err; + cg4 = create_and_get_cgroup("/cg1/cg2/cg3/cg4"); + if (!cg4) + goto err; + cg5 = create_and_get_cgroup("/cg1/cg2/cg3/cg4/cg5"); + if (!cg5) + goto err; + + if (join_cgroup("/cg1/cg2/cg3/cg4/cg5")) + goto err; + + if (bpf_prog_attach(allow_prog[0], cg1, BPF_CGROUP_INET_EGRESS, + BPF_F_ALLOW_MULTI)) { + log_err("Attaching prog to cg1"); + goto err; + } + if (!bpf_prog_attach(allow_prog[0], cg1, BPF_CGROUP_INET_EGRESS, + BPF_F_ALLOW_MULTI)) { + log_err("Unexpected success attaching the same prog to cg1"); + goto err; + } + if (bpf_prog_attach(allow_prog[1], cg1, BPF_CGROUP_INET_EGRESS, + BPF_F_ALLOW_MULTI)) { + log_err("Attaching prog2 to cg1"); + goto err; + } + if (bpf_prog_attach(allow_prog[2], cg2, BPF_CGROUP_INET_EGRESS, + BPF_F_ALLOW_OVERRIDE)) { + log_err("Attaching prog to cg2"); + goto err; + } + if (bpf_prog_attach(allow_prog[3], cg3, BPF_CGROUP_INET_EGRESS, + BPF_F_ALLOW_MULTI)) { + log_err("Attaching prog to cg3"); + goto err; + } + if (bpf_prog_attach(allow_prog[4], cg4, BPF_CGROUP_INET_EGRESS, + BPF_F_ALLOW_OVERRIDE)) { + log_err("Attaching prog to cg4"); + goto err; + } + if (bpf_prog_attach(allow_prog[5], cg5, BPF_CGROUP_INET_EGRESS, 0)) { + log_err("Attaching prog to cg5"); + goto err; + } + assert(system(PING_CMD) == 0); + assert(bpf_map_lookup_elem(map_fd, &key, &value) == 0); + assert(value == 1 + 2 + 8 + 32); + + /* query the number of effective progs in cg5 */ + assert(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, BPF_F_QUERY_EFFECTIVE, + NULL, NULL, &prog_cnt) == 0); + assert(prog_cnt == 4); + /* retrieve prog_ids of effective progs in cg5 */ + assert(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, BPF_F_QUERY_EFFECTIVE, + &attach_flags, prog_ids, &prog_cnt) == 0); + assert(prog_cnt == 4); + assert(attach_flags == 0); + saved_prog_id = prog_ids[0]; + /* check enospc handling */ + prog_ids[0] = 0; + prog_cnt = 2; + assert(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, BPF_F_QUERY_EFFECTIVE, + &attach_flags, prog_ids, &prog_cnt) == -1 && + errno == ENOSPC); + assert(prog_cnt == 4); + /* check that prog_ids are returned even when buffer is too small */ + assert(prog_ids[0] == saved_prog_id); + /* retrieve prog_id of single attached prog in cg5 */ + prog_ids[0] = 0; + assert(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, 0, + NULL, prog_ids, &prog_cnt) == 0); + assert(prog_cnt == 1); + assert(prog_ids[0] == saved_prog_id); + + /* detach bottom program and ping again */ + if (bpf_prog_detach2(-1, cg5, BPF_CGROUP_INET_EGRESS)) { + log_err("Detaching prog from cg5"); + goto err; + } + value = 0; + assert(bpf_map_update_elem(map_fd, &key, &value, 0) == 0); + assert(system(PING_CMD) == 0); + assert(bpf_map_lookup_elem(map_fd, &key, &value) == 0); + assert(value == 1 + 2 + 8 + 16); + + /* detach 3rd from bottom program and ping again */ + errno = 0; + if (!bpf_prog_detach2(0, cg3, BPF_CGROUP_INET_EGRESS)) { + log_err("Unexpected success on detach from cg3"); + goto err; + } + if (bpf_prog_detach2(allow_prog[3], cg3, BPF_CGROUP_INET_EGRESS)) { + log_err("Detaching from cg3"); + goto err; + } + value = 0; + assert(bpf_map_update_elem(map_fd, &key, &value, 0) == 0); + assert(system(PING_CMD) == 0); + assert(bpf_map_lookup_elem(map_fd, &key, &value) == 0); + assert(value == 1 + 2 + 16); + + /* detach 2nd from bottom program and ping again */ + if (bpf_prog_detach2(-1, cg4, BPF_CGROUP_INET_EGRESS)) { + log_err("Detaching prog from cg4"); + goto err; + } + value = 0; + assert(bpf_map_update_elem(map_fd, &key, &value, 0) == 0); + assert(system(PING_CMD) == 0); + assert(bpf_map_lookup_elem(map_fd, &key, &value) == 0); + assert(value == 1 + 2 + 4); + + prog_cnt = 4; + assert(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, BPF_F_QUERY_EFFECTIVE, + &attach_flags, prog_ids, &prog_cnt) == 0); + assert(prog_cnt == 3); + assert(attach_flags == 0); + assert(bpf_prog_query(cg5, BPF_CGROUP_INET_EGRESS, 0, + NULL, prog_ids, &prog_cnt) == 0); + assert(prog_cnt == 0); + goto out; +err: + rc = 1; + +out: + for (i = 0; i < 6; i++) + if (allow_prog[i] > 0) + close(allow_prog[i]); + close(cg1); + close(cg2); + close(cg3); + close(cg4); + close(cg5); + cleanup_cgroup_environment(); + if (!rc) + printf("### multi:PASS\n"); + else + printf("### multi:FAIL\n"); + return rc; +} + +int main(int argc, char **argv) +{ + int rc = 0; + + rc = test_foo_bar(); + if (rc) + return rc; + + return test_multiprog(); +} |