Daniel Borkmann | 42984d7 | 2015-10-29 14:58:10 +0100 | [diff] [blame^] | 1 | #include <linux/unistd.h> |
| 2 | #include <linux/bpf.h> |
| 3 | |
| 4 | #include <stdio.h> |
| 5 | #include <stdlib.h> |
| 6 | #include <stdint.h> |
| 7 | #include <unistd.h> |
| 8 | #include <string.h> |
| 9 | #include <assert.h> |
| 10 | #include <errno.h> |
| 11 | |
| 12 | #include <sys/types.h> |
| 13 | #include <sys/socket.h> |
| 14 | |
| 15 | #include "bpf_load.h" |
| 16 | #include "libbpf.h" |
| 17 | |
| 18 | #define BPF_F_PIN (1 << 0) |
| 19 | #define BPF_F_GET (1 << 1) |
| 20 | #define BPF_F_PIN_GET (BPF_F_PIN | BPF_F_GET) |
| 21 | |
| 22 | #define BPF_F_KEY (1 << 2) |
| 23 | #define BPF_F_VAL (1 << 3) |
| 24 | #define BPF_F_KEY_VAL (BPF_F_KEY | BPF_F_VAL) |
| 25 | |
| 26 | #define BPF_M_UNSPEC 0 |
| 27 | #define BPF_M_MAP 1 |
| 28 | #define BPF_M_PROG 2 |
| 29 | |
| 30 | static void usage(void) |
| 31 | { |
| 32 | printf("Usage: fds_example [...]\n"); |
| 33 | printf(" -F <file> File to pin/get object\n"); |
| 34 | printf(" -P |- pin object\n"); |
| 35 | printf(" -G `- get object\n"); |
| 36 | printf(" -m eBPF map mode\n"); |
| 37 | printf(" -k <key> |- map key\n"); |
| 38 | printf(" -v <value> `- map value\n"); |
| 39 | printf(" -p eBPF prog mode\n"); |
| 40 | printf(" -o <object> `- object file\n"); |
| 41 | printf(" -h Display this help.\n"); |
| 42 | } |
| 43 | |
| 44 | static int bpf_map_create(void) |
| 45 | { |
| 46 | return bpf_create_map(BPF_MAP_TYPE_ARRAY, sizeof(uint32_t), |
| 47 | sizeof(uint32_t), 1024); |
| 48 | } |
| 49 | |
| 50 | static int bpf_prog_create(const char *object) |
| 51 | { |
| 52 | static const struct bpf_insn insns[] = { |
| 53 | BPF_MOV64_IMM(BPF_REG_0, 1), |
| 54 | BPF_EXIT_INSN(), |
| 55 | }; |
| 56 | |
| 57 | if (object) { |
| 58 | assert(!load_bpf_file((char *)object)); |
| 59 | return prog_fd[0]; |
| 60 | } else { |
| 61 | return bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, |
| 62 | insns, sizeof(insns), "GPL", 0); |
| 63 | } |
| 64 | } |
| 65 | |
| 66 | static int bpf_do_map(const char *file, uint32_t flags, uint32_t key, |
| 67 | uint32_t value) |
| 68 | { |
| 69 | int fd, ret; |
| 70 | |
| 71 | if (flags & BPF_F_PIN) { |
| 72 | fd = bpf_map_create(); |
| 73 | printf("bpf: map fd:%d (%s)\n", fd, strerror(errno)); |
| 74 | assert(fd > 0); |
| 75 | |
| 76 | ret = bpf_obj_pin(fd, file); |
| 77 | printf("bpf: pin ret:(%d,%s)\n", ret, strerror(errno)); |
| 78 | assert(ret == 0); |
| 79 | } else { |
| 80 | fd = bpf_obj_get(file); |
| 81 | printf("bpf: get fd:%d (%s)\n", fd, strerror(errno)); |
| 82 | assert(fd > 0); |
| 83 | } |
| 84 | |
| 85 | if ((flags & BPF_F_KEY_VAL) == BPF_F_KEY_VAL) { |
| 86 | ret = bpf_update_elem(fd, &key, &value, 0); |
| 87 | printf("bpf: fd:%d u->(%u:%u) ret:(%d,%s)\n", fd, key, value, |
| 88 | ret, strerror(errno)); |
| 89 | assert(ret == 0); |
| 90 | } else if (flags & BPF_F_KEY) { |
| 91 | ret = bpf_lookup_elem(fd, &key, &value); |
| 92 | printf("bpf: fd:%d l->(%u):%u ret:(%d,%s)\n", fd, key, value, |
| 93 | ret, strerror(errno)); |
| 94 | assert(ret == 0); |
| 95 | } |
| 96 | |
| 97 | return 0; |
| 98 | } |
| 99 | |
| 100 | static int bpf_do_prog(const char *file, uint32_t flags, const char *object) |
| 101 | { |
| 102 | int fd, sock, ret; |
| 103 | |
| 104 | if (flags & BPF_F_PIN) { |
| 105 | fd = bpf_prog_create(object); |
| 106 | printf("bpf: prog fd:%d (%s)\n", fd, strerror(errno)); |
| 107 | assert(fd > 0); |
| 108 | |
| 109 | ret = bpf_obj_pin(fd, file); |
| 110 | printf("bpf: pin ret:(%d,%s)\n", ret, strerror(errno)); |
| 111 | assert(ret == 0); |
| 112 | } else { |
| 113 | fd = bpf_obj_get(file); |
| 114 | printf("bpf: get fd:%d (%s)\n", fd, strerror(errno)); |
| 115 | assert(fd > 0); |
| 116 | } |
| 117 | |
| 118 | sock = open_raw_sock("lo"); |
| 119 | assert(sock > 0); |
| 120 | |
| 121 | ret = setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &fd, sizeof(fd)); |
| 122 | printf("bpf: sock:%d <- fd:%d attached ret:(%d,%s)\n", sock, fd, |
| 123 | ret, strerror(errno)); |
| 124 | assert(ret == 0); |
| 125 | |
| 126 | return 0; |
| 127 | } |
| 128 | |
| 129 | int main(int argc, char **argv) |
| 130 | { |
| 131 | const char *file = NULL, *object = NULL; |
| 132 | uint32_t key = 0, value = 0, flags = 0; |
| 133 | int opt, mode = BPF_M_UNSPEC; |
| 134 | |
| 135 | while ((opt = getopt(argc, argv, "F:PGmk:v:po:")) != -1) { |
| 136 | switch (opt) { |
| 137 | /* General args */ |
| 138 | case 'F': |
| 139 | file = optarg; |
| 140 | break; |
| 141 | case 'P': |
| 142 | flags |= BPF_F_PIN; |
| 143 | break; |
| 144 | case 'G': |
| 145 | flags |= BPF_F_GET; |
| 146 | break; |
| 147 | /* Map-related args */ |
| 148 | case 'm': |
| 149 | mode = BPF_M_MAP; |
| 150 | break; |
| 151 | case 'k': |
| 152 | key = strtoul(optarg, NULL, 0); |
| 153 | flags |= BPF_F_KEY; |
| 154 | break; |
| 155 | case 'v': |
| 156 | value = strtoul(optarg, NULL, 0); |
| 157 | flags |= BPF_F_VAL; |
| 158 | break; |
| 159 | /* Prog-related args */ |
| 160 | case 'p': |
| 161 | mode = BPF_M_PROG; |
| 162 | break; |
| 163 | case 'o': |
| 164 | object = optarg; |
| 165 | break; |
| 166 | default: |
| 167 | goto out; |
| 168 | } |
| 169 | } |
| 170 | |
| 171 | if (!(flags & BPF_F_PIN_GET) || !file) |
| 172 | goto out; |
| 173 | |
| 174 | switch (mode) { |
| 175 | case BPF_M_MAP: |
| 176 | return bpf_do_map(file, flags, key, value); |
| 177 | case BPF_M_PROG: |
| 178 | return bpf_do_prog(file, flags, object); |
| 179 | } |
| 180 | out: |
| 181 | usage(); |
| 182 | return -1; |
| 183 | } |