diff options
Diffstat (limited to 'samples/bpf/test_map_in_map_kern.c')
| -rw-r--r-- | samples/bpf/test_map_in_map_kern.c | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/samples/bpf/test_map_in_map_kern.c b/samples/bpf/test_map_in_map_kern.c new file mode 100644 index 000000000000..42c44d091dd1 --- /dev/null +++ b/samples/bpf/test_map_in_map_kern.c @@ -0,0 +1,173 @@ +/* + * Copyright (c) 2017 Facebook + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ +#define KBUILD_MODNAME "foo" +#include <linux/ptrace.h> +#include <linux/version.h> +#include <uapi/linux/bpf.h> +#include <uapi/linux/in6.h> +#include "bpf_helpers.h" + +#define MAX_NR_PORTS 65536 + +/* map #0 */ +struct bpf_map_def SEC("maps") port_a = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(u32), + .value_size = sizeof(int), + .max_entries = MAX_NR_PORTS, +}; + +/* map #1 */ +struct bpf_map_def SEC("maps") port_h = { + .type = BPF_MAP_TYPE_HASH, + .key_size = sizeof(u32), + .value_size = sizeof(int), + .max_entries = 1, +}; + +/* map #2 */ +struct bpf_map_def SEC("maps") reg_result_h = { + .type = BPF_MAP_TYPE_HASH, + .key_size = sizeof(u32), + .value_size = sizeof(int), + .max_entries = 1, +}; + +/* map #3 */ +struct bpf_map_def SEC("maps") inline_result_h = { + .type = BPF_MAP_TYPE_HASH, + .key_size = sizeof(u32), + .value_size = sizeof(int), + .max_entries = 1, +}; + +/* map #4 */ /* Test case #0 */ +struct bpf_map_def SEC("maps") a_of_port_a = { + .type = BPF_MAP_TYPE_ARRAY_OF_MAPS, + .key_size = sizeof(u32), + .inner_map_idx = 0, /* map_fd[0] is port_a */ + .max_entries = MAX_NR_PORTS, +}; + +/* map #5 */ /* Test case #1 */ +struct bpf_map_def SEC("maps") h_of_port_a = { + .type = BPF_MAP_TYPE_HASH_OF_MAPS, + .key_size = sizeof(u32), + .inner_map_idx = 0, /* map_fd[0] is port_a */ + .max_entries = 1, +}; + +/* map #6 */ /* Test case #2 */ +struct bpf_map_def SEC("maps") h_of_port_h = { + .type = BPF_MAP_TYPE_HASH_OF_MAPS, + .key_size = sizeof(u32), + .inner_map_idx = 1, /* map_fd[1] is port_h */ + .max_entries = 1, +}; + +static __always_inline int do_reg_lookup(void *inner_map, u32 port) +{ + int *result; + + result = bpf_map_lookup_elem(inner_map, &port); + return result ? *result : -ENOENT; +} + +static __always_inline int do_inline_array_lookup(void *inner_map, u32 port) +{ + int *result; + + if (inner_map != &port_a) + return -EINVAL; + + result = bpf_map_lookup_elem(&port_a, &port); + return result ? *result : -ENOENT; +} + +static __always_inline int do_inline_hash_lookup(void *inner_map, u32 port) +{ + int *result; + + if (inner_map != &port_h) + return -EINVAL; + + result = bpf_map_lookup_elem(&port_h, &port); + return result ? *result : -ENOENT; +} + +SEC("kprobe/sys_connect") +int trace_sys_connect(struct pt_regs *ctx) +{ + struct sockaddr_in6 *in6; + u16 test_case, port, dst6[8]; + int addrlen, ret, inline_ret, ret_key = 0; + u32 port_key; + void *outer_map, *inner_map; + bool inline_hash = false; + + in6 = (struct sockaddr_in6 *)PT_REGS_PARM2(ctx); + addrlen = (int)PT_REGS_PARM3(ctx); + + if (addrlen != sizeof(*in6)) + return 0; + + ret = bpf_probe_read(dst6, sizeof(dst6), &in6->sin6_addr); + if (ret) { + inline_ret = ret; + goto done; + } + + if (dst6[0] != 0xdead || dst6[1] != 0xbeef) + return 0; + + test_case = dst6[7]; + + ret = bpf_probe_read(&port, sizeof(port), &in6->sin6_port); + if (ret) { + inline_ret = ret; + goto done; + } + + port_key = port; + + ret = -ENOENT; + if (test_case == 0) { + outer_map = &a_of_port_a; + } else if (test_case == 1) { + outer_map = &h_of_port_a; + } else if (test_case == 2) { + outer_map = &h_of_port_h; + } else { + ret = __LINE__; + inline_ret = ret; + goto done; + } + + inner_map = bpf_map_lookup_elem(outer_map, &port_key); + if (!inner_map) { + ret = __LINE__; + inline_ret = ret; + goto done; + } + + ret = do_reg_lookup(inner_map, port_key); + + if (test_case == 0 || test_case == 1) + inline_ret = do_inline_array_lookup(inner_map, port_key); + else + inline_ret = do_inline_hash_lookup(inner_map, port_key); + +done: + bpf_map_update_elem(®_result_h, &ret_key, &ret, BPF_ANY); + bpf_map_update_elem(&inline_result_h, &ret_key, &inline_ret, BPF_ANY); + + return 0; +} + +char _license[] SEC("license") = "GPL"; +u32 _version SEC("version") = LINUX_VERSION_CODE; |