Jiri Pirko | 1d129d1 | 2015-01-19 16:56:29 +0100 | [diff] [blame] | 1 | /* |
| 2 | * tc_bpf.c BPF common code |
| 3 | * |
| 4 | * This program is free software; you can distribute it and/or |
| 5 | * modify it under the terms of the GNU General Public License |
| 6 | * as published by the Free Software Foundation; either version |
| 7 | * 2 of the License, or (at your option) any later version. |
| 8 | * |
| 9 | * Authors: Daniel Borkmann <dborkman@redhat.com> |
| 10 | * Jiri Pirko <jiri@resnulli.us> |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 11 | * Alexei Starovoitov <ast@plumgrid.com> |
Jiri Pirko | 1d129d1 | 2015-01-19 16:56:29 +0100 | [diff] [blame] | 12 | */ |
| 13 | |
| 14 | #include <stdio.h> |
| 15 | #include <stdlib.h> |
| 16 | #include <unistd.h> |
| 17 | #include <string.h> |
| 18 | #include <stdbool.h> |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 19 | #include <stdint.h> |
Jiri Pirko | 1d129d1 | 2015-01-19 16:56:29 +0100 | [diff] [blame] | 20 | #include <errno.h> |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 21 | #include <fcntl.h> |
| 22 | #include <stdarg.h> |
Gustavo Zacarias | 5c5a0f3 | 2016-04-08 09:59:33 -0300 | [diff] [blame] | 23 | #include <limits.h> |
Jiri Pirko | 1d129d1 | 2015-01-19 16:56:29 +0100 | [diff] [blame] | 24 | |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 25 | #ifdef HAVE_ELF |
| 26 | #include <libelf.h> |
| 27 | #include <gelf.h> |
| 28 | #endif |
| 29 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 30 | #include <sys/types.h> |
| 31 | #include <sys/stat.h> |
| 32 | #include <sys/un.h> |
| 33 | #include <sys/vfs.h> |
| 34 | #include <sys/mount.h> |
| 35 | #include <sys/syscall.h> |
| 36 | #include <sys/sendfile.h> |
| 37 | #include <sys/resource.h> |
| 38 | |
| 39 | #include <linux/bpf.h> |
| 40 | #include <linux/filter.h> |
| 41 | #include <linux/if_alg.h> |
| 42 | |
Daniel Borkmann | 8187b01 | 2016-01-12 02:03:08 +0100 | [diff] [blame] | 43 | #include <arpa/inet.h> |
| 44 | |
Jiri Pirko | 1d129d1 | 2015-01-19 16:56:29 +0100 | [diff] [blame] | 45 | #include "utils.h" |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 46 | |
| 47 | #include "bpf_elf.h" |
| 48 | #include "bpf_scm.h" |
| 49 | |
Jiri Pirko | 1d129d1 | 2015-01-19 16:56:29 +0100 | [diff] [blame] | 50 | #include "tc_util.h" |
| 51 | #include "tc_bpf.h" |
| 52 | |
Nicolas Dichtel | 67584e3 | 2016-02-03 09:25:00 +0100 | [diff] [blame] | 53 | #ifndef AF_ALG |
| 54 | #define AF_ALG 38 |
| 55 | #endif |
| 56 | |
Daniel Borkmann | e77fa41 | 2016-07-19 01:09:52 +0200 | [diff] [blame] | 57 | #ifndef EM_BPF |
| 58 | #define EM_BPF 247 |
| 59 | #endif |
| 60 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 61 | #ifdef HAVE_ELF |
| 62 | static int bpf_obj_open(const char *path, enum bpf_prog_type type, |
| 63 | const char *sec, bool verbose); |
| 64 | #else |
| 65 | static int bpf_obj_open(const char *path, enum bpf_prog_type type, |
| 66 | const char *sec, bool verbose) |
| 67 | { |
| 68 | fprintf(stderr, "No ELF library support compiled in.\n"); |
| 69 | errno = ENOSYS; |
| 70 | return -1; |
| 71 | } |
| 72 | #endif |
| 73 | |
| 74 | static inline __u64 bpf_ptr_to_u64(const void *ptr) |
| 75 | { |
| 76 | return (__u64)(unsigned long)ptr; |
| 77 | } |
| 78 | |
| 79 | static int bpf(int cmd, union bpf_attr *attr, unsigned int size) |
| 80 | { |
| 81 | #ifdef __NR_bpf |
| 82 | return syscall(__NR_bpf, cmd, attr, size); |
| 83 | #else |
| 84 | fprintf(stderr, "No bpf syscall, kernel headers too old?\n"); |
| 85 | errno = ENOSYS; |
| 86 | return -1; |
| 87 | #endif |
| 88 | } |
| 89 | |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 90 | static int bpf_map_update(int fd, const void *key, const void *value, |
| 91 | uint64_t flags) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 92 | { |
Nicolas Dichtel | 67584e3 | 2016-02-03 09:25:00 +0100 | [diff] [blame] | 93 | union bpf_attr attr; |
| 94 | |
| 95 | memset(&attr, 0, sizeof(attr)); |
| 96 | attr.map_fd = fd; |
| 97 | attr.key = bpf_ptr_to_u64(key); |
| 98 | attr.value = bpf_ptr_to_u64(value); |
| 99 | attr.flags = flags; |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 100 | |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 101 | return bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr)); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 102 | } |
| 103 | |
| 104 | static int bpf_parse_string(char *arg, bool from_file, __u16 *bpf_len, |
| 105 | char **bpf_string, bool *need_release, |
| 106 | const char separator) |
Jiri Pirko | 1d129d1 | 2015-01-19 16:56:29 +0100 | [diff] [blame] | 107 | { |
| 108 | char sp; |
| 109 | |
| 110 | if (from_file) { |
| 111 | size_t tmp_len, op_len = sizeof("65535 255 255 4294967295,"); |
| 112 | char *tmp_string; |
| 113 | FILE *fp; |
| 114 | |
| 115 | tmp_len = sizeof("4096,") + BPF_MAXINSNS * op_len; |
| 116 | tmp_string = malloc(tmp_len); |
| 117 | if (tmp_string == NULL) |
| 118 | return -ENOMEM; |
| 119 | |
| 120 | memset(tmp_string, 0, tmp_len); |
| 121 | |
| 122 | fp = fopen(arg, "r"); |
| 123 | if (fp == NULL) { |
| 124 | perror("Cannot fopen"); |
| 125 | free(tmp_string); |
| 126 | return -ENOENT; |
| 127 | } |
| 128 | |
| 129 | if (!fgets(tmp_string, tmp_len, fp)) { |
| 130 | free(tmp_string); |
| 131 | fclose(fp); |
| 132 | return -EIO; |
| 133 | } |
| 134 | |
| 135 | fclose(fp); |
| 136 | |
| 137 | *need_release = true; |
| 138 | *bpf_string = tmp_string; |
| 139 | } else { |
| 140 | *need_release = false; |
| 141 | *bpf_string = arg; |
| 142 | } |
| 143 | |
| 144 | if (sscanf(*bpf_string, "%hu%c", bpf_len, &sp) != 2 || |
| 145 | sp != separator) { |
| 146 | if (*need_release) |
| 147 | free(*bpf_string); |
| 148 | return -EINVAL; |
| 149 | } |
| 150 | |
| 151 | return 0; |
| 152 | } |
| 153 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 154 | static int bpf_ops_parse(int argc, char **argv, struct sock_filter *bpf_ops, |
| 155 | bool from_file) |
Jiri Pirko | 1d129d1 | 2015-01-19 16:56:29 +0100 | [diff] [blame] | 156 | { |
| 157 | char *bpf_string, *token, separator = ','; |
| 158 | int ret = 0, i = 0; |
| 159 | bool need_release; |
| 160 | __u16 bpf_len = 0; |
| 161 | |
| 162 | if (argc < 1) |
| 163 | return -EINVAL; |
| 164 | if (bpf_parse_string(argv[0], from_file, &bpf_len, &bpf_string, |
| 165 | &need_release, separator)) |
| 166 | return -EINVAL; |
| 167 | if (bpf_len == 0 || bpf_len > BPF_MAXINSNS) { |
| 168 | ret = -EINVAL; |
| 169 | goto out; |
| 170 | } |
| 171 | |
| 172 | token = bpf_string; |
| 173 | while ((token = strchr(token, separator)) && (++token)[0]) { |
| 174 | if (i >= bpf_len) { |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 175 | fprintf(stderr, "Real program length exceeds encoded length parameter!\n"); |
Jiri Pirko | 1d129d1 | 2015-01-19 16:56:29 +0100 | [diff] [blame] | 176 | ret = -EINVAL; |
| 177 | goto out; |
| 178 | } |
| 179 | |
| 180 | if (sscanf(token, "%hu %hhu %hhu %u,", |
| 181 | &bpf_ops[i].code, &bpf_ops[i].jt, |
| 182 | &bpf_ops[i].jf, &bpf_ops[i].k) != 4) { |
| 183 | fprintf(stderr, "Error at instruction %d!\n", i); |
| 184 | ret = -EINVAL; |
| 185 | goto out; |
| 186 | } |
| 187 | |
| 188 | i++; |
| 189 | } |
| 190 | |
| 191 | if (i != bpf_len) { |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 192 | fprintf(stderr, "Parsed program length is less than encoded length parameter!\n"); |
Jiri Pirko | 1d129d1 | 2015-01-19 16:56:29 +0100 | [diff] [blame] | 193 | ret = -EINVAL; |
| 194 | goto out; |
| 195 | } |
| 196 | ret = bpf_len; |
Jiri Pirko | 1d129d1 | 2015-01-19 16:56:29 +0100 | [diff] [blame] | 197 | out: |
| 198 | if (need_release) |
| 199 | free(bpf_string); |
| 200 | |
| 201 | return ret; |
| 202 | } |
| 203 | |
| 204 | void bpf_print_ops(FILE *f, struct rtattr *bpf_ops, __u16 len) |
| 205 | { |
| 206 | struct sock_filter *ops = (struct sock_filter *) RTA_DATA(bpf_ops); |
| 207 | int i; |
| 208 | |
| 209 | if (len == 0) |
| 210 | return; |
| 211 | |
| 212 | fprintf(f, "bytecode \'%u,", len); |
| 213 | |
| 214 | for (i = 0; i < len - 1; i++) |
| 215 | fprintf(f, "%hu %hhu %hhu %u,", ops[i].code, ops[i].jt, |
| 216 | ops[i].jf, ops[i].k); |
| 217 | |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 218 | fprintf(f, "%hu %hhu %hhu %u\'", ops[i].code, ops[i].jt, |
Jiri Pirko | 1d129d1 | 2015-01-19 16:56:29 +0100 | [diff] [blame] | 219 | ops[i].jf, ops[i].k); |
| 220 | } |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 221 | |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 222 | static void bpf_map_pin_report(const struct bpf_elf_map *pin, |
| 223 | const struct bpf_elf_map *obj) |
| 224 | { |
| 225 | fprintf(stderr, "Map specification differs from pinned file!\n"); |
| 226 | |
| 227 | if (obj->type != pin->type) |
| 228 | fprintf(stderr, " - Type: %u (obj) != %u (pin)\n", |
| 229 | obj->type, pin->type); |
| 230 | if (obj->size_key != pin->size_key) |
| 231 | fprintf(stderr, " - Size key: %u (obj) != %u (pin)\n", |
| 232 | obj->size_key, pin->size_key); |
| 233 | if (obj->size_value != pin->size_value) |
| 234 | fprintf(stderr, " - Size value: %u (obj) != %u (pin)\n", |
| 235 | obj->size_value, pin->size_value); |
| 236 | if (obj->max_elem != pin->max_elem) |
| 237 | fprintf(stderr, " - Max elems: %u (obj) != %u (pin)\n", |
| 238 | obj->max_elem, pin->max_elem); |
Daniel Borkmann | 4dd3f50 | 2016-04-09 00:32:05 +0200 | [diff] [blame] | 239 | if (obj->flags != pin->flags) |
| 240 | fprintf(stderr, " - Flags: %#x (obj) != %#x (pin)\n", |
| 241 | obj->flags, pin->flags); |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 242 | |
| 243 | fprintf(stderr, "\n"); |
| 244 | } |
| 245 | |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 246 | static int bpf_map_selfcheck_pinned(int fd, const struct bpf_elf_map *map, |
| 247 | int length) |
Daniel Borkmann | 9e607f2 | 2015-11-26 15:38:43 +0100 | [diff] [blame] | 248 | { |
| 249 | char file[PATH_MAX], buff[4096]; |
| 250 | struct bpf_elf_map tmp, zero; |
| 251 | unsigned int val; |
| 252 | FILE *fp; |
| 253 | |
| 254 | snprintf(file, sizeof(file), "/proc/%d/fdinfo/%d", getpid(), fd); |
| 255 | |
| 256 | fp = fopen(file, "r"); |
| 257 | if (!fp) { |
| 258 | fprintf(stderr, "No procfs support?!\n"); |
| 259 | return -EIO; |
| 260 | } |
| 261 | |
| 262 | memset(&tmp, 0, sizeof(tmp)); |
| 263 | while (fgets(buff, sizeof(buff), fp)) { |
| 264 | if (sscanf(buff, "map_type:\t%u", &val) == 1) |
| 265 | tmp.type = val; |
| 266 | else if (sscanf(buff, "key_size:\t%u", &val) == 1) |
| 267 | tmp.size_key = val; |
| 268 | else if (sscanf(buff, "value_size:\t%u", &val) == 1) |
| 269 | tmp.size_value = val; |
| 270 | else if (sscanf(buff, "max_entries:\t%u", &val) == 1) |
| 271 | tmp.max_elem = val; |
Daniel Borkmann | 4dd3f50 | 2016-04-09 00:32:05 +0200 | [diff] [blame] | 272 | else if (sscanf(buff, "map_flags:\t%i", &val) == 1) |
| 273 | tmp.flags = val; |
Daniel Borkmann | 9e607f2 | 2015-11-26 15:38:43 +0100 | [diff] [blame] | 274 | } |
| 275 | |
| 276 | fclose(fp); |
| 277 | |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 278 | if (!memcmp(&tmp, map, length)) { |
Daniel Borkmann | 9e607f2 | 2015-11-26 15:38:43 +0100 | [diff] [blame] | 279 | return 0; |
| 280 | } else { |
| 281 | memset(&zero, 0, sizeof(zero)); |
| 282 | /* If kernel doesn't have eBPF-related fdinfo, we cannot do much, |
| 283 | * so just accept it. We know we do have an eBPF fd and in this |
| 284 | * case, everything is 0. It is guaranteed that no such map exists |
| 285 | * since map type of 0 is unloadable BPF_MAP_TYPE_UNSPEC. |
| 286 | */ |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 287 | if (!memcmp(&tmp, &zero, length)) |
Daniel Borkmann | 9e607f2 | 2015-11-26 15:38:43 +0100 | [diff] [blame] | 288 | return 0; |
| 289 | |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 290 | bpf_map_pin_report(&tmp, map); |
Daniel Borkmann | 9e607f2 | 2015-11-26 15:38:43 +0100 | [diff] [blame] | 291 | return -EINVAL; |
| 292 | } |
| 293 | } |
| 294 | |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 295 | static int bpf_mnt_fs(const char *target) |
| 296 | { |
| 297 | bool bind_done = false; |
| 298 | |
| 299 | while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) { |
| 300 | if (errno != EINVAL || bind_done) { |
| 301 | fprintf(stderr, "mount --make-private %s failed: %s\n", |
| 302 | target, strerror(errno)); |
| 303 | return -1; |
| 304 | } |
| 305 | |
| 306 | if (mount(target, target, "none", MS_BIND, NULL)) { |
| 307 | fprintf(stderr, "mount --bind %s %s failed: %s\n", |
| 308 | target, target, strerror(errno)); |
| 309 | return -1; |
| 310 | } |
| 311 | |
| 312 | bind_done = true; |
| 313 | } |
| 314 | |
| 315 | if (mount("bpf", target, "bpf", 0, NULL)) { |
| 316 | fprintf(stderr, "mount -t bpf bpf %s failed: %s\n", |
| 317 | target, strerror(errno)); |
| 318 | return -1; |
| 319 | } |
| 320 | |
| 321 | return 0; |
| 322 | } |
| 323 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 324 | static int bpf_valid_mntpt(const char *mnt, unsigned long magic) |
| 325 | { |
| 326 | struct statfs st_fs; |
| 327 | |
| 328 | if (statfs(mnt, &st_fs) < 0) |
| 329 | return -ENOENT; |
| 330 | if ((unsigned long)st_fs.f_type != magic) |
| 331 | return -ENOENT; |
| 332 | |
| 333 | return 0; |
| 334 | } |
| 335 | |
| 336 | static const char *bpf_find_mntpt(const char *fstype, unsigned long magic, |
| 337 | char *mnt, int len, |
| 338 | const char * const *known_mnts) |
| 339 | { |
| 340 | const char * const *ptr; |
| 341 | char type[100]; |
| 342 | FILE *fp; |
| 343 | |
| 344 | if (known_mnts) { |
| 345 | ptr = known_mnts; |
| 346 | while (*ptr) { |
| 347 | if (bpf_valid_mntpt(*ptr, magic) == 0) { |
| 348 | strncpy(mnt, *ptr, len - 1); |
| 349 | mnt[len - 1] = 0; |
| 350 | return mnt; |
| 351 | } |
| 352 | ptr++; |
| 353 | } |
| 354 | } |
| 355 | |
| 356 | fp = fopen("/proc/mounts", "r"); |
| 357 | if (fp == NULL || len != PATH_MAX) |
| 358 | return NULL; |
| 359 | |
| 360 | while (fscanf(fp, "%*s %" textify(PATH_MAX) "s %99s %*s %*d %*d\n", |
| 361 | mnt, type) == 2) { |
| 362 | if (strcmp(type, fstype) == 0) |
| 363 | break; |
| 364 | } |
| 365 | |
| 366 | fclose(fp); |
| 367 | if (strcmp(type, fstype) != 0) |
| 368 | return NULL; |
| 369 | |
| 370 | return mnt; |
| 371 | } |
| 372 | |
| 373 | int bpf_trace_pipe(void) |
| 374 | { |
| 375 | char tracefs_mnt[PATH_MAX] = TRACE_DIR_MNT; |
| 376 | static const char * const tracefs_known_mnts[] = { |
| 377 | TRACE_DIR_MNT, |
| 378 | "/sys/kernel/debug/tracing", |
| 379 | "/tracing", |
| 380 | "/trace", |
| 381 | 0, |
| 382 | }; |
| 383 | char tpipe[PATH_MAX]; |
| 384 | const char *mnt; |
| 385 | int fd; |
| 386 | |
| 387 | mnt = bpf_find_mntpt("tracefs", TRACEFS_MAGIC, tracefs_mnt, |
| 388 | sizeof(tracefs_mnt), tracefs_known_mnts); |
| 389 | if (!mnt) { |
| 390 | fprintf(stderr, "tracefs not mounted?\n"); |
| 391 | return -1; |
| 392 | } |
| 393 | |
| 394 | snprintf(tpipe, sizeof(tpipe), "%s/trace_pipe", mnt); |
| 395 | |
| 396 | fd = open(tpipe, O_RDONLY); |
| 397 | if (fd < 0) |
| 398 | return -1; |
| 399 | |
| 400 | fprintf(stderr, "Running! Hang up with ^C!\n\n"); |
| 401 | while (1) { |
| 402 | static char buff[4096]; |
| 403 | ssize_t ret; |
| 404 | |
| 405 | ret = read(fd, buff, sizeof(buff) - 1); |
| 406 | if (ret > 0) { |
| 407 | write(2, buff, ret); |
| 408 | fflush(stderr); |
| 409 | } |
| 410 | } |
| 411 | |
| 412 | return 0; |
| 413 | } |
| 414 | |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 415 | static const char *bpf_get_tc_dir(void) |
| 416 | { |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 417 | static bool bpf_mnt_cached; |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 418 | static char bpf_tc_dir[PATH_MAX]; |
| 419 | static const char *mnt; |
| 420 | static const char * const bpf_known_mnts[] = { |
| 421 | BPF_DIR_MNT, |
| 422 | 0, |
| 423 | }; |
| 424 | char bpf_mnt[PATH_MAX] = BPF_DIR_MNT; |
| 425 | char bpf_glo_dir[PATH_MAX]; |
| 426 | int ret; |
| 427 | |
| 428 | if (bpf_mnt_cached) |
| 429 | goto done; |
| 430 | |
| 431 | mnt = bpf_find_mntpt("bpf", BPF_FS_MAGIC, bpf_mnt, sizeof(bpf_mnt), |
| 432 | bpf_known_mnts); |
| 433 | if (!mnt) { |
| 434 | mnt = getenv(BPF_ENV_MNT); |
| 435 | if (!mnt) |
| 436 | mnt = BPF_DIR_MNT; |
| 437 | ret = bpf_mnt_fs(mnt); |
| 438 | if (ret) { |
| 439 | mnt = NULL; |
| 440 | goto out; |
| 441 | } |
| 442 | } |
| 443 | |
| 444 | snprintf(bpf_tc_dir, sizeof(bpf_tc_dir), "%s/%s", mnt, BPF_DIR_TC); |
| 445 | ret = mkdir(bpf_tc_dir, S_IRWXU); |
| 446 | if (ret && errno != EEXIST) { |
| 447 | fprintf(stderr, "mkdir %s failed: %s\n", bpf_tc_dir, |
| 448 | strerror(errno)); |
| 449 | mnt = NULL; |
| 450 | goto out; |
| 451 | } |
| 452 | |
| 453 | snprintf(bpf_glo_dir, sizeof(bpf_glo_dir), "%s/%s", |
| 454 | bpf_tc_dir, BPF_DIR_GLOBALS); |
| 455 | ret = mkdir(bpf_glo_dir, S_IRWXU); |
| 456 | if (ret && errno != EEXIST) { |
| 457 | fprintf(stderr, "mkdir %s failed: %s\n", bpf_glo_dir, |
| 458 | strerror(errno)); |
| 459 | mnt = NULL; |
| 460 | goto out; |
| 461 | } |
| 462 | |
| 463 | mnt = bpf_tc_dir; |
| 464 | out: |
| 465 | bpf_mnt_cached = true; |
| 466 | done: |
| 467 | return mnt; |
| 468 | } |
| 469 | |
| 470 | static int bpf_obj_get(const char *pathname) |
| 471 | { |
| 472 | union bpf_attr attr; |
| 473 | char tmp[PATH_MAX]; |
| 474 | |
| 475 | if (strlen(pathname) > 2 && pathname[0] == 'm' && |
| 476 | pathname[1] == ':' && bpf_get_tc_dir()) { |
| 477 | snprintf(tmp, sizeof(tmp), "%s/%s", |
| 478 | bpf_get_tc_dir(), pathname + 2); |
| 479 | pathname = tmp; |
| 480 | } |
| 481 | |
| 482 | memset(&attr, 0, sizeof(attr)); |
| 483 | attr.pathname = bpf_ptr_to_u64(pathname); |
| 484 | |
| 485 | return bpf(BPF_OBJ_GET, &attr, sizeof(attr)); |
| 486 | } |
| 487 | |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 488 | const char *bpf_default_section(const enum bpf_prog_type type) |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 489 | { |
| 490 | switch (type) { |
| 491 | case BPF_PROG_TYPE_SCHED_CLS: |
| 492 | return ELF_SECTION_CLASSIFIER; |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 493 | case BPF_PROG_TYPE_SCHED_ACT: |
| 494 | return ELF_SECTION_ACTION; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 495 | default: |
| 496 | return NULL; |
| 497 | } |
| 498 | } |
| 499 | |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 500 | enum bpf_mode { |
| 501 | CBPF_BYTECODE = 0, |
| 502 | CBPF_FILE, |
| 503 | EBPF_OBJECT, |
| 504 | EBPF_PINNED, |
| 505 | __BPF_MODE_MAX, |
| 506 | #define BPF_MODE_MAX __BPF_MODE_MAX |
| 507 | }; |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 508 | |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 509 | static int bpf_parse(int *ptr_argc, char ***ptr_argv, const bool *opt_tbl, |
| 510 | enum bpf_prog_type *type, enum bpf_mode *mode, |
| 511 | const char **ptr_object, const char **ptr_section, |
| 512 | const char **ptr_uds_name, struct sock_filter *opcodes) |
| 513 | { |
| 514 | const char *file, *section, *uds_name; |
| 515 | bool verbose = false; |
| 516 | int ret, argc; |
| 517 | char **argv; |
| 518 | |
| 519 | argv = *ptr_argv; |
| 520 | argc = *ptr_argc; |
| 521 | |
| 522 | if (opt_tbl[CBPF_BYTECODE] && |
| 523 | (matches(*argv, "bytecode") == 0 || |
| 524 | strcmp(*argv, "bc") == 0)) { |
| 525 | *mode = CBPF_BYTECODE; |
| 526 | } else if (opt_tbl[CBPF_FILE] && |
| 527 | (matches(*argv, "bytecode-file") == 0 || |
| 528 | strcmp(*argv, "bcf") == 0)) { |
| 529 | *mode = CBPF_FILE; |
| 530 | } else if (opt_tbl[EBPF_OBJECT] && |
| 531 | (matches(*argv, "object-file") == 0 || |
| 532 | strcmp(*argv, "obj") == 0)) { |
| 533 | *mode = EBPF_OBJECT; |
| 534 | } else if (opt_tbl[EBPF_PINNED] && |
| 535 | (matches(*argv, "object-pinned") == 0 || |
| 536 | matches(*argv, "pinned") == 0 || |
| 537 | matches(*argv, "fd") == 0)) { |
| 538 | *mode = EBPF_PINNED; |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 539 | } else { |
| 540 | fprintf(stderr, "What mode is \"%s\"?\n", *argv); |
| 541 | return -1; |
| 542 | } |
| 543 | |
| 544 | NEXT_ARG(); |
| 545 | file = section = uds_name = NULL; |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 546 | if (*mode == EBPF_OBJECT || *mode == EBPF_PINNED) { |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 547 | file = *argv; |
| 548 | NEXT_ARG_FWD(); |
| 549 | |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 550 | if (*type == BPF_PROG_TYPE_UNSPEC) { |
| 551 | if (argc > 0 && matches(*argv, "type") == 0) { |
| 552 | NEXT_ARG(); |
| 553 | if (matches(*argv, "cls") == 0) { |
| 554 | *type = BPF_PROG_TYPE_SCHED_CLS; |
| 555 | } else if (matches(*argv, "act") == 0) { |
| 556 | *type = BPF_PROG_TYPE_SCHED_ACT; |
| 557 | } else { |
| 558 | fprintf(stderr, "What type is \"%s\"?\n", |
| 559 | *argv); |
| 560 | return -1; |
| 561 | } |
| 562 | NEXT_ARG_FWD(); |
| 563 | } else { |
| 564 | *type = BPF_PROG_TYPE_SCHED_CLS; |
| 565 | } |
| 566 | } |
| 567 | |
| 568 | section = bpf_default_section(*type); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 569 | if (argc > 0 && matches(*argv, "section") == 0) { |
| 570 | NEXT_ARG(); |
| 571 | section = *argv; |
| 572 | NEXT_ARG_FWD(); |
| 573 | } |
| 574 | |
| 575 | uds_name = getenv(BPF_ENV_UDS); |
| 576 | if (argc > 0 && !uds_name && |
| 577 | matches(*argv, "export") == 0) { |
| 578 | NEXT_ARG(); |
| 579 | uds_name = *argv; |
| 580 | NEXT_ARG_FWD(); |
| 581 | } |
| 582 | |
| 583 | if (argc > 0 && matches(*argv, "verbose") == 0) { |
| 584 | verbose = true; |
| 585 | NEXT_ARG_FWD(); |
| 586 | } |
| 587 | |
| 588 | PREV_ARG(); |
| 589 | } |
| 590 | |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 591 | if (*mode == CBPF_BYTECODE || *mode == CBPF_FILE) |
| 592 | ret = bpf_ops_parse(argc, argv, opcodes, *mode == CBPF_FILE); |
| 593 | else if (*mode == EBPF_OBJECT) |
| 594 | ret = bpf_obj_open(file, *type, section, verbose); |
| 595 | else if (*mode == EBPF_PINNED) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 596 | ret = bpf_obj_get(file); |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 597 | else |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 598 | return -1; |
| 599 | |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 600 | if (ptr_object) |
| 601 | *ptr_object = file; |
| 602 | if (ptr_section) |
| 603 | *ptr_section = section; |
| 604 | if (ptr_uds_name) |
| 605 | *ptr_uds_name = uds_name; |
| 606 | |
| 607 | *ptr_argc = argc; |
| 608 | *ptr_argv = argv; |
| 609 | |
| 610 | return ret; |
| 611 | } |
| 612 | |
| 613 | int bpf_parse_common(int *ptr_argc, char ***ptr_argv, const int *nla_tbl, |
| 614 | enum bpf_prog_type type, const char **ptr_object, |
| 615 | const char **ptr_uds_name, struct nlmsghdr *n) |
| 616 | { |
| 617 | struct sock_filter opcodes[BPF_MAXINSNS]; |
| 618 | const bool opt_tbl[BPF_MODE_MAX] = { |
| 619 | [CBPF_BYTECODE] = true, |
| 620 | [CBPF_FILE] = true, |
| 621 | [EBPF_OBJECT] = true, |
| 622 | [EBPF_PINNED] = true, |
| 623 | }; |
| 624 | char annotation[256]; |
| 625 | const char *section; |
| 626 | enum bpf_mode mode; |
| 627 | int ret; |
| 628 | |
| 629 | ret = bpf_parse(ptr_argc, ptr_argv, opt_tbl, &type, &mode, |
| 630 | ptr_object, §ion, ptr_uds_name, opcodes); |
| 631 | if (ret < 0) |
| 632 | return ret; |
| 633 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 634 | if (mode == CBPF_BYTECODE || mode == CBPF_FILE) { |
| 635 | addattr16(n, MAX_MSG, nla_tbl[BPF_NLA_OPS_LEN], ret); |
| 636 | addattr_l(n, MAX_MSG, nla_tbl[BPF_NLA_OPS], opcodes, |
| 637 | ret * sizeof(struct sock_filter)); |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 638 | } |
| 639 | |
| 640 | if (mode == EBPF_OBJECT || mode == EBPF_PINNED) { |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 641 | snprintf(annotation, sizeof(annotation), "%s:[%s]", |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 642 | basename(*ptr_object), mode == EBPF_PINNED ? |
| 643 | "*fsobj" : section); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 644 | |
| 645 | addattr32(n, MAX_MSG, nla_tbl[BPF_NLA_FD], ret); |
| 646 | addattrstrz(n, MAX_MSG, nla_tbl[BPF_NLA_NAME], annotation); |
| 647 | } |
| 648 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 649 | return 0; |
| 650 | } |
| 651 | |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 652 | int bpf_graft_map(const char *map_path, uint32_t *key, int argc, char **argv) |
| 653 | { |
| 654 | enum bpf_prog_type type = BPF_PROG_TYPE_UNSPEC; |
| 655 | const bool opt_tbl[BPF_MODE_MAX] = { |
| 656 | [CBPF_BYTECODE] = false, |
| 657 | [CBPF_FILE] = false, |
| 658 | [EBPF_OBJECT] = true, |
| 659 | [EBPF_PINNED] = true, |
| 660 | }; |
| 661 | const struct bpf_elf_map test = { |
| 662 | .type = BPF_MAP_TYPE_PROG_ARRAY, |
| 663 | .size_key = sizeof(int), |
| 664 | .size_value = sizeof(int), |
| 665 | }; |
| 666 | int ret, prog_fd, map_fd; |
| 667 | const char *section; |
| 668 | enum bpf_mode mode; |
| 669 | uint32_t map_key; |
| 670 | |
| 671 | prog_fd = bpf_parse(&argc, &argv, opt_tbl, &type, &mode, |
| 672 | NULL, §ion, NULL, NULL); |
| 673 | if (prog_fd < 0) |
| 674 | return prog_fd; |
| 675 | if (key) { |
| 676 | map_key = *key; |
| 677 | } else { |
| 678 | ret = sscanf(section, "%*i/%i", &map_key); |
| 679 | if (ret != 1) { |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 680 | fprintf(stderr, "Couldn\'t infer map key from section name! Please provide \'key\' argument!\n"); |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 681 | ret = -EINVAL; |
| 682 | goto out_prog; |
| 683 | } |
| 684 | } |
| 685 | |
| 686 | map_fd = bpf_obj_get(map_path); |
| 687 | if (map_fd < 0) { |
| 688 | fprintf(stderr, "Couldn\'t retrieve pinned map \'%s\': %s\n", |
| 689 | map_path, strerror(errno)); |
| 690 | ret = map_fd; |
| 691 | goto out_prog; |
| 692 | } |
| 693 | |
| 694 | ret = bpf_map_selfcheck_pinned(map_fd, &test, |
| 695 | offsetof(struct bpf_elf_map, max_elem)); |
| 696 | if (ret < 0) { |
| 697 | fprintf(stderr, "Map \'%s\' self-check failed!\n", map_path); |
| 698 | goto out_map; |
| 699 | } |
| 700 | |
| 701 | ret = bpf_map_update(map_fd, &map_key, &prog_fd, BPF_ANY); |
| 702 | if (ret < 0) |
| 703 | fprintf(stderr, "Map update failed: %s\n", strerror(errno)); |
| 704 | out_map: |
| 705 | close(map_fd); |
| 706 | out_prog: |
| 707 | close(prog_fd); |
| 708 | return ret; |
| 709 | } |
| 710 | |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 711 | #ifdef HAVE_ELF |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 712 | struct bpf_elf_prog { |
| 713 | enum bpf_prog_type type; |
| 714 | const struct bpf_insn *insns; |
| 715 | size_t size; |
| 716 | const char *license; |
| 717 | }; |
| 718 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 719 | struct bpf_hash_entry { |
| 720 | unsigned int pinning; |
| 721 | const char *subpath; |
| 722 | struct bpf_hash_entry *next; |
| 723 | }; |
| 724 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 725 | struct bpf_elf_ctx { |
| 726 | Elf *elf_fd; |
| 727 | GElf_Ehdr elf_hdr; |
| 728 | Elf_Data *sym_tab; |
| 729 | Elf_Data *str_tab; |
| 730 | int obj_fd; |
| 731 | int map_fds[ELF_MAX_MAPS]; |
| 732 | struct bpf_elf_map maps[ELF_MAX_MAPS]; |
| 733 | int sym_num; |
| 734 | int map_num; |
| 735 | bool *sec_done; |
| 736 | int sec_maps; |
| 737 | char license[ELF_MAX_LICENSE_LEN]; |
| 738 | enum bpf_prog_type type; |
| 739 | bool verbose; |
| 740 | struct bpf_elf_st stat; |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 741 | struct bpf_hash_entry *ht[256]; |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 742 | char *log; |
| 743 | size_t log_size; |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 744 | }; |
| 745 | |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 746 | struct bpf_elf_sec_data { |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 747 | GElf_Shdr sec_hdr; |
| 748 | Elf_Data *sec_data; |
| 749 | const char *sec_name; |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 750 | }; |
| 751 | |
| 752 | struct bpf_map_data { |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 753 | int *fds; |
| 754 | const char *obj; |
| 755 | struct bpf_elf_st *st; |
| 756 | struct bpf_elf_map *ent; |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 757 | }; |
| 758 | |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 759 | static __check_format_string(2, 3) void |
| 760 | bpf_dump_error(struct bpf_elf_ctx *ctx, const char *format, ...) |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 761 | { |
| 762 | va_list vl; |
| 763 | |
| 764 | va_start(vl, format); |
| 765 | vfprintf(stderr, format, vl); |
| 766 | va_end(vl); |
| 767 | |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 768 | if (ctx->log && ctx->log[0]) { |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 769 | if (ctx->verbose) { |
| 770 | fprintf(stderr, "%s\n", ctx->log); |
| 771 | } else { |
| 772 | unsigned int off = 0, len = strlen(ctx->log); |
| 773 | |
| 774 | if (len > BPF_MAX_LOG) { |
| 775 | off = len - BPF_MAX_LOG; |
| 776 | fprintf(stderr, "Skipped %u bytes, use \'verb\' option for the full verbose log.\n[...]\n", |
| 777 | off); |
| 778 | } |
| 779 | fprintf(stderr, "%s\n", ctx->log + off); |
| 780 | } |
| 781 | |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 782 | memset(ctx->log, 0, ctx->log_size); |
Daniel Borkmann | d937a74 | 2015-04-28 13:37:42 +0200 | [diff] [blame] | 783 | } |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 784 | } |
| 785 | |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 786 | static int bpf_log_realloc(struct bpf_elf_ctx *ctx) |
| 787 | { |
| 788 | size_t log_size = ctx->log_size; |
| 789 | void *ptr; |
| 790 | |
| 791 | if (!ctx->log) { |
| 792 | log_size = 65536; |
| 793 | } else { |
| 794 | log_size <<= 1; |
| 795 | if (log_size > (UINT_MAX >> 8)) |
| 796 | return -EINVAL; |
| 797 | } |
| 798 | |
| 799 | ptr = realloc(ctx->log, log_size); |
| 800 | if (!ptr) |
| 801 | return -ENOMEM; |
| 802 | |
| 803 | ctx->log = ptr; |
| 804 | ctx->log_size = log_size; |
| 805 | |
| 806 | return 0; |
| 807 | } |
| 808 | |
Daniel Borkmann | 4dd3f50 | 2016-04-09 00:32:05 +0200 | [diff] [blame] | 809 | static int bpf_map_create(enum bpf_map_type type, uint32_t size_key, |
| 810 | uint32_t size_value, uint32_t max_elem, |
| 811 | uint32_t flags) |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 812 | { |
Nicolas Dichtel | 67584e3 | 2016-02-03 09:25:00 +0100 | [diff] [blame] | 813 | union bpf_attr attr; |
| 814 | |
| 815 | memset(&attr, 0, sizeof(attr)); |
| 816 | attr.map_type = type; |
| 817 | attr.key_size = size_key; |
| 818 | attr.value_size = size_value; |
| 819 | attr.max_entries = max_elem; |
Daniel Borkmann | 4dd3f50 | 2016-04-09 00:32:05 +0200 | [diff] [blame] | 820 | attr.map_flags = flags; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 821 | |
| 822 | return bpf(BPF_MAP_CREATE, &attr, sizeof(attr)); |
| 823 | } |
| 824 | |
| 825 | static int bpf_prog_load(enum bpf_prog_type type, const struct bpf_insn *insns, |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 826 | size_t size_insns, const char *license, char *log, |
| 827 | size_t size_log) |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 828 | { |
Nicolas Dichtel | 67584e3 | 2016-02-03 09:25:00 +0100 | [diff] [blame] | 829 | union bpf_attr attr; |
| 830 | |
| 831 | memset(&attr, 0, sizeof(attr)); |
| 832 | attr.prog_type = type; |
| 833 | attr.insns = bpf_ptr_to_u64(insns); |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 834 | attr.insn_cnt = size_insns / sizeof(struct bpf_insn); |
Nicolas Dichtel | 67584e3 | 2016-02-03 09:25:00 +0100 | [diff] [blame] | 835 | attr.license = bpf_ptr_to_u64(license); |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 836 | |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 837 | if (size_log > 0) { |
| 838 | attr.log_buf = bpf_ptr_to_u64(log); |
| 839 | attr.log_size = size_log; |
| 840 | attr.log_level = 1; |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 841 | } |
| 842 | |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 843 | return bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); |
| 844 | } |
| 845 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 846 | static int bpf_obj_pin(int fd, const char *pathname) |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 847 | { |
Nicolas Dichtel | 67584e3 | 2016-02-03 09:25:00 +0100 | [diff] [blame] | 848 | union bpf_attr attr; |
| 849 | |
| 850 | memset(&attr, 0, sizeof(attr)); |
| 851 | attr.pathname = bpf_ptr_to_u64(pathname); |
| 852 | attr.bpf_fd = fd; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 853 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 854 | return bpf(BPF_OBJ_PIN, &attr, sizeof(attr)); |
| 855 | } |
| 856 | |
| 857 | static int bpf_obj_hash(const char *object, uint8_t *out, size_t len) |
| 858 | { |
| 859 | struct sockaddr_alg alg = { |
| 860 | .salg_family = AF_ALG, |
| 861 | .salg_type = "hash", |
| 862 | .salg_name = "sha1", |
| 863 | }; |
| 864 | int ret, cfd, ofd, ffd; |
| 865 | struct stat stbuff; |
| 866 | ssize_t size; |
| 867 | |
| 868 | if (!object || len != 20) |
| 869 | return -EINVAL; |
| 870 | |
| 871 | cfd = socket(AF_ALG, SOCK_SEQPACKET, 0); |
| 872 | if (cfd < 0) { |
| 873 | fprintf(stderr, "Cannot get AF_ALG socket: %s\n", |
| 874 | strerror(errno)); |
| 875 | return cfd; |
Daniel Borkmann | d937a74 | 2015-04-28 13:37:42 +0200 | [diff] [blame] | 876 | } |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 877 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 878 | ret = bind(cfd, (struct sockaddr *)&alg, sizeof(alg)); |
| 879 | if (ret < 0) { |
| 880 | fprintf(stderr, "Error binding socket: %s\n", strerror(errno)); |
| 881 | goto out_cfd; |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 882 | } |
| 883 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 884 | ofd = accept(cfd, NULL, 0); |
| 885 | if (ofd < 0) { |
| 886 | fprintf(stderr, "Error accepting socket: %s\n", |
| 887 | strerror(errno)); |
| 888 | ret = ofd; |
| 889 | goto out_cfd; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 890 | } |
| 891 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 892 | ffd = open(object, O_RDONLY); |
| 893 | if (ffd < 0) { |
| 894 | fprintf(stderr, "Error opening object %s: %s\n", |
| 895 | object, strerror(errno)); |
| 896 | ret = ffd; |
| 897 | goto out_ofd; |
| 898 | } |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 899 | |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 900 | ret = fstat(ffd, &stbuff); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 901 | if (ret < 0) { |
| 902 | fprintf(stderr, "Error doing fstat: %s\n", |
| 903 | strerror(errno)); |
| 904 | goto out_ffd; |
| 905 | } |
| 906 | |
| 907 | size = sendfile(ofd, ffd, NULL, stbuff.st_size); |
| 908 | if (size != stbuff.st_size) { |
| 909 | fprintf(stderr, "Error from sendfile (%zd vs %zu bytes): %s\n", |
| 910 | size, stbuff.st_size, strerror(errno)); |
| 911 | ret = -1; |
| 912 | goto out_ffd; |
| 913 | } |
| 914 | |
| 915 | size = read(ofd, out, len); |
| 916 | if (size != len) { |
| 917 | fprintf(stderr, "Error from read (%zd vs %zu bytes): %s\n", |
| 918 | size, len, strerror(errno)); |
| 919 | ret = -1; |
| 920 | } else { |
| 921 | ret = 0; |
| 922 | } |
| 923 | out_ffd: |
| 924 | close(ffd); |
| 925 | out_ofd: |
| 926 | close(ofd); |
| 927 | out_cfd: |
| 928 | close(cfd); |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 929 | return ret; |
| 930 | } |
| 931 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 932 | static const char *bpf_get_obj_uid(const char *pathname) |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 933 | { |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 934 | static bool bpf_uid_cached; |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 935 | static char bpf_uid[64]; |
| 936 | uint8_t tmp[20]; |
| 937 | int ret; |
| 938 | |
| 939 | if (bpf_uid_cached) |
| 940 | goto done; |
| 941 | |
| 942 | ret = bpf_obj_hash(pathname, tmp, sizeof(tmp)); |
| 943 | if (ret) { |
| 944 | fprintf(stderr, "Object hashing failed!\n"); |
| 945 | return NULL; |
| 946 | } |
| 947 | |
| 948 | hexstring_n2a(tmp, sizeof(tmp), bpf_uid, sizeof(bpf_uid)); |
| 949 | bpf_uid_cached = true; |
| 950 | done: |
| 951 | return bpf_uid; |
| 952 | } |
| 953 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 954 | static int bpf_init_env(const char *pathname) |
| 955 | { |
| 956 | struct rlimit limit = { |
| 957 | .rlim_cur = RLIM_INFINITY, |
| 958 | .rlim_max = RLIM_INFINITY, |
| 959 | }; |
| 960 | |
| 961 | /* Don't bother in case we fail! */ |
| 962 | setrlimit(RLIMIT_MEMLOCK, &limit); |
| 963 | |
| 964 | if (!bpf_get_tc_dir()) { |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 965 | fprintf(stderr, "Continuing without mounted eBPF fs. Too old kernel?\n"); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 966 | return 0; |
| 967 | } |
| 968 | |
| 969 | if (!bpf_get_obj_uid(pathname)) |
| 970 | return -1; |
| 971 | |
| 972 | return 0; |
| 973 | } |
| 974 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 975 | static const char *bpf_custom_pinning(const struct bpf_elf_ctx *ctx, |
| 976 | uint32_t pinning) |
| 977 | { |
| 978 | struct bpf_hash_entry *entry; |
| 979 | |
| 980 | entry = ctx->ht[pinning & (ARRAY_SIZE(ctx->ht) - 1)]; |
| 981 | while (entry && entry->pinning != pinning) |
| 982 | entry = entry->next; |
| 983 | |
| 984 | return entry ? entry->subpath : NULL; |
| 985 | } |
| 986 | |
| 987 | static bool bpf_no_pinning(const struct bpf_elf_ctx *ctx, |
| 988 | uint32_t pinning) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 989 | { |
| 990 | switch (pinning) { |
| 991 | case PIN_OBJECT_NS: |
| 992 | case PIN_GLOBAL_NS: |
| 993 | return false; |
| 994 | case PIN_NONE: |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 995 | return true; |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 996 | default: |
| 997 | return !bpf_custom_pinning(ctx, pinning); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 998 | } |
| 999 | } |
| 1000 | |
| 1001 | static void bpf_make_pathname(char *pathname, size_t len, const char *name, |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1002 | const struct bpf_elf_ctx *ctx, uint32_t pinning) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1003 | { |
| 1004 | switch (pinning) { |
| 1005 | case PIN_OBJECT_NS: |
| 1006 | snprintf(pathname, len, "%s/%s/%s", bpf_get_tc_dir(), |
| 1007 | bpf_get_obj_uid(NULL), name); |
| 1008 | break; |
| 1009 | case PIN_GLOBAL_NS: |
| 1010 | snprintf(pathname, len, "%s/%s/%s", bpf_get_tc_dir(), |
| 1011 | BPF_DIR_GLOBALS, name); |
| 1012 | break; |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1013 | default: |
| 1014 | snprintf(pathname, len, "%s/../%s/%s", bpf_get_tc_dir(), |
| 1015 | bpf_custom_pinning(ctx, pinning), name); |
| 1016 | break; |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1017 | } |
| 1018 | } |
| 1019 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1020 | static int bpf_probe_pinned(const char *name, const struct bpf_elf_ctx *ctx, |
| 1021 | uint32_t pinning) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1022 | { |
| 1023 | char pathname[PATH_MAX]; |
| 1024 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1025 | if (bpf_no_pinning(ctx, pinning) || !bpf_get_tc_dir()) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1026 | return 0; |
| 1027 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1028 | bpf_make_pathname(pathname, sizeof(pathname), name, ctx, pinning); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1029 | return bpf_obj_get(pathname); |
| 1030 | } |
| 1031 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1032 | static int bpf_make_obj_path(void) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1033 | { |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1034 | char tmp[PATH_MAX]; |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1035 | int ret; |
| 1036 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1037 | snprintf(tmp, sizeof(tmp), "%s/%s", bpf_get_tc_dir(), |
| 1038 | bpf_get_obj_uid(NULL)); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1039 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1040 | ret = mkdir(tmp, S_IRWXU); |
| 1041 | if (ret && errno != EEXIST) { |
| 1042 | fprintf(stderr, "mkdir %s failed: %s\n", tmp, strerror(errno)); |
| 1043 | return ret; |
| 1044 | } |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1045 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1046 | return 0; |
| 1047 | } |
| 1048 | |
| 1049 | static int bpf_make_custom_path(const char *todo) |
| 1050 | { |
| 1051 | char tmp[PATH_MAX], rem[PATH_MAX], *sub; |
| 1052 | int ret; |
| 1053 | |
| 1054 | snprintf(tmp, sizeof(tmp), "%s/../", bpf_get_tc_dir()); |
| 1055 | snprintf(rem, sizeof(rem), "%s/", todo); |
| 1056 | sub = strtok(rem, "/"); |
| 1057 | |
| 1058 | while (sub) { |
| 1059 | if (strlen(tmp) + strlen(sub) + 2 > PATH_MAX) |
| 1060 | return -EINVAL; |
| 1061 | |
| 1062 | strcat(tmp, sub); |
| 1063 | strcat(tmp, "/"); |
| 1064 | |
| 1065 | ret = mkdir(tmp, S_IRWXU); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1066 | if (ret && errno != EEXIST) { |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1067 | fprintf(stderr, "mkdir %s failed: %s\n", tmp, |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1068 | strerror(errno)); |
| 1069 | return ret; |
| 1070 | } |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1071 | |
| 1072 | sub = strtok(NULL, "/"); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1073 | } |
| 1074 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1075 | return 0; |
| 1076 | } |
| 1077 | |
| 1078 | static int bpf_place_pinned(int fd, const char *name, |
| 1079 | const struct bpf_elf_ctx *ctx, uint32_t pinning) |
| 1080 | { |
| 1081 | char pathname[PATH_MAX]; |
| 1082 | const char *tmp; |
| 1083 | int ret = 0; |
| 1084 | |
| 1085 | if (bpf_no_pinning(ctx, pinning) || !bpf_get_tc_dir()) |
| 1086 | return 0; |
| 1087 | |
| 1088 | if (pinning == PIN_OBJECT_NS) |
| 1089 | ret = bpf_make_obj_path(); |
| 1090 | else if ((tmp = bpf_custom_pinning(ctx, pinning))) |
| 1091 | ret = bpf_make_custom_path(tmp); |
| 1092 | if (ret < 0) |
| 1093 | return ret; |
| 1094 | |
| 1095 | bpf_make_pathname(pathname, sizeof(pathname), name, ctx, pinning); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1096 | return bpf_obj_pin(fd, pathname); |
| 1097 | } |
| 1098 | |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1099 | static void bpf_prog_report(int fd, const char *section, |
| 1100 | const struct bpf_elf_prog *prog, |
| 1101 | struct bpf_elf_ctx *ctx) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1102 | { |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 1103 | unsigned int insns = prog->size / sizeof(struct bpf_insn); |
| 1104 | |
| 1105 | fprintf(stderr, "\nProg section \'%s\' %s%s (%d)!\n", section, |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1106 | fd < 0 ? "rejected: " : "loaded", |
| 1107 | fd < 0 ? strerror(errno) : "", |
| 1108 | fd < 0 ? errno : fd); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1109 | |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1110 | fprintf(stderr, " - Type: %u\n", prog->type); |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 1111 | fprintf(stderr, " - Instructions: %u (%u over limit)\n", |
| 1112 | insns, insns > BPF_MAXINSNS ? insns - BPF_MAXINSNS : 0); |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1113 | fprintf(stderr, " - License: %s\n\n", prog->license); |
| 1114 | |
| 1115 | bpf_dump_error(ctx, "Verifier analysis:\n\n"); |
| 1116 | } |
| 1117 | |
| 1118 | static int bpf_prog_attach(const char *section, |
| 1119 | const struct bpf_elf_prog *prog, |
| 1120 | struct bpf_elf_ctx *ctx) |
| 1121 | { |
| 1122 | int tries = 0, fd; |
| 1123 | retry: |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1124 | errno = 0; |
| 1125 | fd = bpf_prog_load(prog->type, prog->insns, prog->size, |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1126 | prog->license, ctx->log, ctx->log_size); |
| 1127 | if (fd < 0 || ctx->verbose) { |
| 1128 | /* The verifier log is pretty chatty, sometimes so chatty |
| 1129 | * on larger programs, that we could fail to dump everything |
| 1130 | * into our buffer. Still, try to give a debuggable error |
| 1131 | * log for the user, so enlarge it and re-fail. |
| 1132 | */ |
| 1133 | if (fd < 0 && (errno == ENOSPC || !ctx->log_size)) { |
| 1134 | if (tries++ < 6 && !bpf_log_realloc(ctx)) |
| 1135 | goto retry; |
| 1136 | |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 1137 | fprintf(stderr, "Log buffer too small to dump verifier log %zu bytes (%d tries)!\n", |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1138 | ctx->log_size, tries); |
| 1139 | return fd; |
| 1140 | } |
| 1141 | |
| 1142 | bpf_prog_report(fd, section, prog, ctx); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1143 | } |
| 1144 | |
| 1145 | return fd; |
| 1146 | } |
| 1147 | |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1148 | static void bpf_map_report(int fd, const char *name, |
| 1149 | const struct bpf_elf_map *map, |
| 1150 | struct bpf_elf_ctx *ctx) |
| 1151 | { |
| 1152 | fprintf(stderr, "Map object \'%s\' %s%s (%d)!\n", name, |
| 1153 | fd < 0 ? "rejected: " : "loaded", |
| 1154 | fd < 0 ? strerror(errno) : "", |
| 1155 | fd < 0 ? errno : fd); |
| 1156 | |
| 1157 | fprintf(stderr, " - Type: %u\n", map->type); |
| 1158 | fprintf(stderr, " - Identifier: %u\n", map->id); |
| 1159 | fprintf(stderr, " - Pinning: %u\n", map->pinning); |
| 1160 | fprintf(stderr, " - Size key: %u\n", map->size_key); |
| 1161 | fprintf(stderr, " - Size value: %u\n", map->size_value); |
Daniel Borkmann | 4dd3f50 | 2016-04-09 00:32:05 +0200 | [diff] [blame] | 1162 | fprintf(stderr, " - Max elems: %u\n", map->max_elem); |
| 1163 | fprintf(stderr, " - Flags: %#x\n\n", map->flags); |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1164 | } |
| 1165 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1166 | static int bpf_map_attach(const char *name, const struct bpf_elf_map *map, |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1167 | struct bpf_elf_ctx *ctx) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1168 | { |
| 1169 | int fd, ret; |
| 1170 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1171 | fd = bpf_probe_pinned(name, ctx, map->pinning); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1172 | if (fd > 0) { |
Daniel Borkmann | 91d88ee | 2015-11-26 15:38:45 +0100 | [diff] [blame] | 1173 | ret = bpf_map_selfcheck_pinned(fd, map, |
| 1174 | offsetof(struct bpf_elf_map, |
| 1175 | id)); |
Daniel Borkmann | 9e607f2 | 2015-11-26 15:38:43 +0100 | [diff] [blame] | 1176 | if (ret < 0) { |
| 1177 | close(fd); |
| 1178 | fprintf(stderr, "Map \'%s\' self-check failed!\n", |
| 1179 | name); |
| 1180 | return ret; |
| 1181 | } |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1182 | if (ctx->verbose) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1183 | fprintf(stderr, "Map \'%s\' loaded as pinned!\n", |
| 1184 | name); |
| 1185 | return fd; |
| 1186 | } |
| 1187 | |
| 1188 | errno = 0; |
| 1189 | fd = bpf_map_create(map->type, map->size_key, map->size_value, |
Daniel Borkmann | 4dd3f50 | 2016-04-09 00:32:05 +0200 | [diff] [blame] | 1190 | map->max_elem, map->flags); |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1191 | if (fd < 0 || ctx->verbose) { |
| 1192 | bpf_map_report(fd, name, map, ctx); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1193 | if (fd < 0) |
| 1194 | return fd; |
| 1195 | } |
| 1196 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1197 | ret = bpf_place_pinned(fd, name, ctx, map->pinning); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1198 | if (ret < 0 && errno != EEXIST) { |
| 1199 | fprintf(stderr, "Could not pin %s map: %s\n", name, |
| 1200 | strerror(errno)); |
| 1201 | close(fd); |
| 1202 | return ret; |
| 1203 | } |
| 1204 | |
| 1205 | return fd; |
| 1206 | } |
| 1207 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1208 | static const char *bpf_str_tab_name(const struct bpf_elf_ctx *ctx, |
| 1209 | const GElf_Sym *sym) |
| 1210 | { |
| 1211 | return ctx->str_tab->d_buf + sym->st_name; |
| 1212 | } |
| 1213 | |
| 1214 | static const char *bpf_map_fetch_name(struct bpf_elf_ctx *ctx, int which) |
| 1215 | { |
| 1216 | GElf_Sym sym; |
| 1217 | int i; |
| 1218 | |
| 1219 | for (i = 0; i < ctx->sym_num; i++) { |
| 1220 | if (gelf_getsym(ctx->sym_tab, i, &sym) != &sym) |
| 1221 | continue; |
| 1222 | |
Daniel Borkmann | 5230a2e | 2016-02-07 02:11:53 +0100 | [diff] [blame] | 1223 | if (GELF_ST_BIND(sym.st_info) != STB_GLOBAL || |
| 1224 | GELF_ST_TYPE(sym.st_info) != STT_NOTYPE || |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1225 | sym.st_shndx != ctx->sec_maps || |
| 1226 | sym.st_value / sizeof(struct bpf_elf_map) != which) |
| 1227 | continue; |
| 1228 | |
| 1229 | return bpf_str_tab_name(ctx, &sym); |
| 1230 | } |
| 1231 | |
| 1232 | return NULL; |
| 1233 | } |
| 1234 | |
| 1235 | static int bpf_maps_attach_all(struct bpf_elf_ctx *ctx) |
| 1236 | { |
| 1237 | const char *map_name; |
| 1238 | int i, fd; |
| 1239 | |
| 1240 | for (i = 0; i < ctx->map_num; i++) { |
| 1241 | map_name = bpf_map_fetch_name(ctx, i); |
| 1242 | if (!map_name) |
| 1243 | return -EIO; |
| 1244 | |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1245 | fd = bpf_map_attach(map_name, &ctx->maps[i], ctx); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1246 | if (fd < 0) |
| 1247 | return fd; |
| 1248 | |
| 1249 | ctx->map_fds[i] = fd; |
| 1250 | } |
| 1251 | |
| 1252 | return 0; |
| 1253 | } |
| 1254 | |
| 1255 | static int bpf_fill_section_data(struct bpf_elf_ctx *ctx, int section, |
| 1256 | struct bpf_elf_sec_data *data) |
| 1257 | { |
| 1258 | Elf_Data *sec_edata; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1259 | GElf_Shdr sec_hdr; |
| 1260 | Elf_Scn *sec_fd; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1261 | char *sec_name; |
| 1262 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1263 | memset(data, 0, sizeof(*data)); |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1264 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1265 | sec_fd = elf_getscn(ctx->elf_fd, section); |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1266 | if (!sec_fd) |
| 1267 | return -EINVAL; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1268 | if (gelf_getshdr(sec_fd, &sec_hdr) != &sec_hdr) |
| 1269 | return -EIO; |
| 1270 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1271 | sec_name = elf_strptr(ctx->elf_fd, ctx->elf_hdr.e_shstrndx, |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1272 | sec_hdr.sh_name); |
| 1273 | if (!sec_name || !sec_hdr.sh_size) |
| 1274 | return -ENOENT; |
| 1275 | |
| 1276 | sec_edata = elf_getdata(sec_fd, NULL); |
| 1277 | if (!sec_edata || elf_getdata(sec_fd, sec_edata)) |
| 1278 | return -EIO; |
| 1279 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1280 | memcpy(&data->sec_hdr, &sec_hdr, sizeof(sec_hdr)); |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1281 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1282 | data->sec_name = sec_name; |
| 1283 | data->sec_data = sec_edata; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1284 | return 0; |
| 1285 | } |
| 1286 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1287 | static int bpf_fetch_maps(struct bpf_elf_ctx *ctx, int section, |
| 1288 | struct bpf_elf_sec_data *data) |
| 1289 | { |
| 1290 | if (data->sec_data->d_size % sizeof(struct bpf_elf_map) != 0) |
| 1291 | return -EINVAL; |
| 1292 | |
| 1293 | ctx->map_num = data->sec_data->d_size / sizeof(struct bpf_elf_map); |
| 1294 | ctx->sec_maps = section; |
| 1295 | ctx->sec_done[section] = true; |
| 1296 | |
| 1297 | if (ctx->map_num > ARRAY_SIZE(ctx->map_fds)) { |
| 1298 | fprintf(stderr, "Too many BPF maps in ELF section!\n"); |
| 1299 | return -ENOMEM; |
| 1300 | } |
| 1301 | |
| 1302 | memcpy(ctx->maps, data->sec_data->d_buf, data->sec_data->d_size); |
| 1303 | return 0; |
| 1304 | } |
| 1305 | |
| 1306 | static int bpf_fetch_license(struct bpf_elf_ctx *ctx, int section, |
| 1307 | struct bpf_elf_sec_data *data) |
| 1308 | { |
| 1309 | if (data->sec_data->d_size > sizeof(ctx->license)) |
| 1310 | return -ENOMEM; |
| 1311 | |
| 1312 | memcpy(ctx->license, data->sec_data->d_buf, data->sec_data->d_size); |
| 1313 | ctx->sec_done[section] = true; |
| 1314 | return 0; |
| 1315 | } |
| 1316 | |
| 1317 | static int bpf_fetch_symtab(struct bpf_elf_ctx *ctx, int section, |
| 1318 | struct bpf_elf_sec_data *data) |
| 1319 | { |
| 1320 | ctx->sym_tab = data->sec_data; |
| 1321 | ctx->sym_num = data->sec_hdr.sh_size / data->sec_hdr.sh_entsize; |
| 1322 | ctx->sec_done[section] = true; |
| 1323 | return 0; |
| 1324 | } |
| 1325 | |
| 1326 | static int bpf_fetch_strtab(struct bpf_elf_ctx *ctx, int section, |
| 1327 | struct bpf_elf_sec_data *data) |
| 1328 | { |
| 1329 | ctx->str_tab = data->sec_data; |
| 1330 | ctx->sec_done[section] = true; |
| 1331 | return 0; |
| 1332 | } |
| 1333 | |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 1334 | static bool bpf_has_map_data(const struct bpf_elf_ctx *ctx) |
| 1335 | { |
| 1336 | return ctx->sym_tab && ctx->str_tab && ctx->sec_maps; |
| 1337 | } |
| 1338 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1339 | static int bpf_fetch_ancillary(struct bpf_elf_ctx *ctx) |
| 1340 | { |
| 1341 | struct bpf_elf_sec_data data; |
| 1342 | int i, ret = -1; |
| 1343 | |
| 1344 | for (i = 1; i < ctx->elf_hdr.e_shnum; i++) { |
| 1345 | ret = bpf_fill_section_data(ctx, i, &data); |
| 1346 | if (ret < 0) |
| 1347 | continue; |
| 1348 | |
Daniel Borkmann | cce3d46 | 2016-01-12 02:03:07 +0100 | [diff] [blame] | 1349 | if (data.sec_hdr.sh_type == SHT_PROGBITS && |
| 1350 | !strcmp(data.sec_name, ELF_SECTION_MAPS)) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1351 | ret = bpf_fetch_maps(ctx, i, &data); |
Daniel Borkmann | cce3d46 | 2016-01-12 02:03:07 +0100 | [diff] [blame] | 1352 | else if (data.sec_hdr.sh_type == SHT_PROGBITS && |
| 1353 | !strcmp(data.sec_name, ELF_SECTION_LICENSE)) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1354 | ret = bpf_fetch_license(ctx, i, &data); |
Daniel Borkmann | cce3d46 | 2016-01-12 02:03:07 +0100 | [diff] [blame] | 1355 | else if (data.sec_hdr.sh_type == SHT_SYMTAB && |
| 1356 | !strcmp(data.sec_name, ".symtab")) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1357 | ret = bpf_fetch_symtab(ctx, i, &data); |
| 1358 | else if (data.sec_hdr.sh_type == SHT_STRTAB && |
Daniel Borkmann | cce3d46 | 2016-01-12 02:03:07 +0100 | [diff] [blame] | 1359 | !strcmp(data.sec_name, ".strtab")) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1360 | ret = bpf_fetch_strtab(ctx, i, &data); |
| 1361 | if (ret < 0) { |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 1362 | fprintf(stderr, "Error parsing section %d! Perhaps check with readelf -a?\n", |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 1363 | i); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1364 | break; |
| 1365 | } |
| 1366 | } |
| 1367 | |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 1368 | if (bpf_has_map_data(ctx)) { |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1369 | ret = bpf_maps_attach_all(ctx); |
| 1370 | if (ret < 0) { |
| 1371 | fprintf(stderr, "Error loading maps into kernel!\n"); |
| 1372 | return ret; |
| 1373 | } |
| 1374 | } |
| 1375 | |
| 1376 | return ret; |
| 1377 | } |
| 1378 | |
| 1379 | static int bpf_fetch_prog(struct bpf_elf_ctx *ctx, const char *section) |
| 1380 | { |
| 1381 | struct bpf_elf_sec_data data; |
| 1382 | struct bpf_elf_prog prog; |
| 1383 | int ret, i, fd = -1; |
| 1384 | |
| 1385 | for (i = 1; i < ctx->elf_hdr.e_shnum; i++) { |
| 1386 | if (ctx->sec_done[i]) |
| 1387 | continue; |
| 1388 | |
| 1389 | ret = bpf_fill_section_data(ctx, i, &data); |
Daniel Borkmann | cce3d46 | 2016-01-12 02:03:07 +0100 | [diff] [blame] | 1390 | if (ret < 0 || |
| 1391 | !(data.sec_hdr.sh_type == SHT_PROGBITS && |
| 1392 | data.sec_hdr.sh_flags & SHF_EXECINSTR && |
| 1393 | !strcmp(data.sec_name, section))) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1394 | continue; |
| 1395 | |
| 1396 | memset(&prog, 0, sizeof(prog)); |
| 1397 | prog.type = ctx->type; |
| 1398 | prog.insns = data.sec_data->d_buf; |
| 1399 | prog.size = data.sec_data->d_size; |
| 1400 | prog.license = ctx->license; |
| 1401 | |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1402 | fd = bpf_prog_attach(section, &prog, ctx); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1403 | if (fd < 0) |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 1404 | break; |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1405 | |
| 1406 | ctx->sec_done[i] = true; |
| 1407 | break; |
| 1408 | } |
| 1409 | |
| 1410 | return fd; |
| 1411 | } |
| 1412 | |
| 1413 | static int bpf_apply_relo_data(struct bpf_elf_ctx *ctx, |
| 1414 | struct bpf_elf_sec_data *data_relo, |
| 1415 | struct bpf_elf_sec_data *data_insn) |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1416 | { |
| 1417 | Elf_Data *idata = data_insn->sec_data; |
| 1418 | GElf_Shdr *rhdr = &data_relo->sec_hdr; |
| 1419 | int relo_ent, relo_num = rhdr->sh_size / rhdr->sh_entsize; |
| 1420 | struct bpf_insn *insns = idata->d_buf; |
| 1421 | unsigned int num_insns = idata->d_size / sizeof(*insns); |
| 1422 | |
| 1423 | for (relo_ent = 0; relo_ent < relo_num; relo_ent++) { |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1424 | unsigned int ioff, rmap; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1425 | GElf_Rel relo; |
| 1426 | GElf_Sym sym; |
| 1427 | |
| 1428 | if (gelf_getrel(data_relo->sec_data, relo_ent, &relo) != &relo) |
| 1429 | return -EIO; |
| 1430 | |
| 1431 | ioff = relo.r_offset / sizeof(struct bpf_insn); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1432 | if (ioff >= num_insns || |
Daniel Borkmann | a576c6b | 2016-02-07 02:11:52 +0100 | [diff] [blame] | 1433 | insns[ioff].code != (BPF_LD | BPF_IMM | BPF_DW)) { |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 1434 | fprintf(stderr, "ELF contains relo data for non ld64 instruction at offset %u! Compiler bug?!\n", |
Daniel Borkmann | a576c6b | 2016-02-07 02:11:52 +0100 | [diff] [blame] | 1435 | ioff); |
| 1436 | if (ioff < num_insns && |
| 1437 | insns[ioff].code == (BPF_JMP | BPF_CALL)) |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 1438 | fprintf(stderr, " - Try to annotate functions with always_inline attribute!\n"); |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1439 | return -EINVAL; |
Daniel Borkmann | a576c6b | 2016-02-07 02:11:52 +0100 | [diff] [blame] | 1440 | } |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1441 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1442 | if (gelf_getsym(ctx->sym_tab, GELF_R_SYM(relo.r_info), &sym) != &sym) |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1443 | return -EIO; |
Daniel Borkmann | 2486337 | 2016-01-22 00:46:28 +0100 | [diff] [blame] | 1444 | if (sym.st_shndx != ctx->sec_maps) { |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 1445 | fprintf(stderr, "ELF contains non-map related relo data in entry %u pointing to section %u! Compiler bug?!\n", |
Daniel Borkmann | 2486337 | 2016-01-22 00:46:28 +0100 | [diff] [blame] | 1446 | relo_ent, sym.st_shndx); |
| 1447 | return -EIO; |
| 1448 | } |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1449 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1450 | rmap = sym.st_value / sizeof(struct bpf_elf_map); |
| 1451 | if (rmap >= ARRAY_SIZE(ctx->map_fds)) |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1452 | return -EINVAL; |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1453 | if (!ctx->map_fds[rmap]) |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1454 | return -EINVAL; |
| 1455 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1456 | if (ctx->verbose) |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 1457 | fprintf(stderr, "Map \'%s\' (%d) injected into prog section \'%s\' at offset %u!\n", |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1458 | bpf_str_tab_name(ctx, &sym), ctx->map_fds[rmap], |
| 1459 | data_insn->sec_name, ioff); |
| 1460 | |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1461 | insns[ioff].src_reg = BPF_PSEUDO_MAP_FD; |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1462 | insns[ioff].imm = ctx->map_fds[rmap]; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1463 | } |
| 1464 | |
| 1465 | return 0; |
| 1466 | } |
| 1467 | |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 1468 | static int bpf_fetch_prog_relo(struct bpf_elf_ctx *ctx, const char *section, |
| 1469 | bool *lderr) |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1470 | { |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1471 | struct bpf_elf_sec_data data_relo, data_insn; |
| 1472 | struct bpf_elf_prog prog; |
| 1473 | int ret, idx, i, fd = -1; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1474 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1475 | for (i = 1; i < ctx->elf_hdr.e_shnum; i++) { |
| 1476 | ret = bpf_fill_section_data(ctx, i, &data_relo); |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1477 | if (ret < 0 || data_relo.sec_hdr.sh_type != SHT_REL) |
| 1478 | continue; |
| 1479 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1480 | idx = data_relo.sec_hdr.sh_info; |
| 1481 | ret = bpf_fill_section_data(ctx, idx, &data_insn); |
Daniel Borkmann | cce3d46 | 2016-01-12 02:03:07 +0100 | [diff] [blame] | 1482 | if (ret < 0 || |
| 1483 | !(data_insn.sec_hdr.sh_type == SHT_PROGBITS && |
| 1484 | data_insn.sec_hdr.sh_flags & SHF_EXECINSTR && |
| 1485 | !strcmp(data_insn.sec_name, section))) |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1486 | continue; |
| 1487 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1488 | ret = bpf_apply_relo_data(ctx, &data_relo, &data_insn); |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1489 | if (ret < 0) |
| 1490 | continue; |
| 1491 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1492 | memset(&prog, 0, sizeof(prog)); |
| 1493 | prog.type = ctx->type; |
| 1494 | prog.insns = data_insn.sec_data->d_buf; |
| 1495 | prog.size = data_insn.sec_data->d_size; |
| 1496 | prog.license = ctx->license; |
| 1497 | |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1498 | fd = bpf_prog_attach(section, &prog, ctx); |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 1499 | if (fd < 0) { |
| 1500 | *lderr = true; |
| 1501 | break; |
| 1502 | } |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1503 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1504 | ctx->sec_done[i] = true; |
| 1505 | ctx->sec_done[idx] = true; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1506 | break; |
| 1507 | } |
| 1508 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1509 | return fd; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1510 | } |
| 1511 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1512 | static int bpf_fetch_prog_sec(struct bpf_elf_ctx *ctx, const char *section) |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 1513 | { |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 1514 | bool lderr = false; |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 1515 | int ret = -1; |
| 1516 | |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 1517 | if (bpf_has_map_data(ctx)) |
| 1518 | ret = bpf_fetch_prog_relo(ctx, section, &lderr); |
| 1519 | if (ret < 0 && !lderr) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1520 | ret = bpf_fetch_prog(ctx, section); |
| 1521 | |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 1522 | return ret; |
| 1523 | } |
| 1524 | |
Daniel Borkmann | 910b543 | 2015-11-26 15:38:42 +0100 | [diff] [blame] | 1525 | static int bpf_find_map_by_id(struct bpf_elf_ctx *ctx, uint32_t id) |
| 1526 | { |
| 1527 | int i; |
| 1528 | |
| 1529 | for (i = 0; i < ARRAY_SIZE(ctx->map_fds); i++) |
| 1530 | if (ctx->map_fds[i] && ctx->maps[i].id == id && |
| 1531 | ctx->maps[i].type == BPF_MAP_TYPE_PROG_ARRAY) |
| 1532 | return i; |
| 1533 | return -1; |
| 1534 | } |
| 1535 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1536 | static int bpf_fill_prog_arrays(struct bpf_elf_ctx *ctx) |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 1537 | { |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1538 | struct bpf_elf_sec_data data; |
| 1539 | uint32_t map_id, key_id; |
Daniel Borkmann | 910b543 | 2015-11-26 15:38:42 +0100 | [diff] [blame] | 1540 | int fd, i, ret, idx; |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 1541 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1542 | for (i = 1; i < ctx->elf_hdr.e_shnum; i++) { |
| 1543 | if (ctx->sec_done[i]) |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 1544 | continue; |
| 1545 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1546 | ret = bpf_fill_section_data(ctx, i, &data); |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 1547 | if (ret < 0) |
| 1548 | continue; |
| 1549 | |
Daniel Borkmann | 910b543 | 2015-11-26 15:38:42 +0100 | [diff] [blame] | 1550 | ret = sscanf(data.sec_name, "%i/%i", &map_id, &key_id); |
| 1551 | if (ret != 2) |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1552 | continue; |
Daniel Borkmann | 910b543 | 2015-11-26 15:38:42 +0100 | [diff] [blame] | 1553 | |
| 1554 | idx = bpf_find_map_by_id(ctx, map_id); |
| 1555 | if (idx < 0) |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 1556 | continue; |
| 1557 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1558 | fd = bpf_fetch_prog_sec(ctx, data.sec_name); |
| 1559 | if (fd < 0) |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 1560 | return -EIO; |
| 1561 | |
Daniel Borkmann | 910b543 | 2015-11-26 15:38:42 +0100 | [diff] [blame] | 1562 | ret = bpf_map_update(ctx->map_fds[idx], &key_id, |
| 1563 | &fd, BPF_ANY); |
Daniel Borkmann | afc1a20 | 2016-04-09 00:32:04 +0200 | [diff] [blame] | 1564 | if (ret < 0) { |
| 1565 | if (errno == E2BIG) |
| 1566 | fprintf(stderr, "Tail call key %u for map %u out of bounds?\n", |
| 1567 | key_id, map_id); |
| 1568 | return -errno; |
| 1569 | } |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 1570 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1571 | ctx->sec_done[i] = true; |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 1572 | } |
| 1573 | |
| 1574 | return 0; |
| 1575 | } |
| 1576 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1577 | static void bpf_save_finfo(struct bpf_elf_ctx *ctx) |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1578 | { |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1579 | struct stat st; |
| 1580 | int ret; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1581 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1582 | memset(&ctx->stat, 0, sizeof(ctx->stat)); |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1583 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1584 | ret = fstat(ctx->obj_fd, &st); |
| 1585 | if (ret < 0) { |
| 1586 | fprintf(stderr, "Stat of elf file failed: %s\n", |
| 1587 | strerror(errno)); |
| 1588 | return; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1589 | } |
| 1590 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1591 | ctx->stat.st_dev = st.st_dev; |
| 1592 | ctx->stat.st_ino = st.st_ino; |
| 1593 | } |
| 1594 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1595 | static int bpf_read_pin_mapping(FILE *fp, uint32_t *id, char *path) |
| 1596 | { |
| 1597 | char buff[PATH_MAX]; |
| 1598 | |
| 1599 | while (fgets(buff, sizeof(buff), fp)) { |
| 1600 | char *ptr = buff; |
| 1601 | |
| 1602 | while (*ptr == ' ' || *ptr == '\t') |
| 1603 | ptr++; |
| 1604 | |
| 1605 | if (*ptr == '#' || *ptr == '\n' || *ptr == 0) |
| 1606 | continue; |
| 1607 | |
| 1608 | if (sscanf(ptr, "%i %s\n", id, path) != 2 && |
| 1609 | sscanf(ptr, "%i %s #", id, path) != 2) { |
| 1610 | strcpy(path, ptr); |
| 1611 | return -1; |
| 1612 | } |
| 1613 | |
| 1614 | return 1; |
| 1615 | } |
| 1616 | |
| 1617 | return 0; |
| 1618 | } |
| 1619 | |
| 1620 | static bool bpf_pinning_reserved(uint32_t pinning) |
| 1621 | { |
| 1622 | switch (pinning) { |
| 1623 | case PIN_NONE: |
| 1624 | case PIN_OBJECT_NS: |
| 1625 | case PIN_GLOBAL_NS: |
| 1626 | return true; |
| 1627 | default: |
| 1628 | return false; |
| 1629 | } |
| 1630 | } |
| 1631 | |
| 1632 | static void bpf_hash_init(struct bpf_elf_ctx *ctx, const char *db_file) |
| 1633 | { |
| 1634 | struct bpf_hash_entry *entry; |
| 1635 | char subpath[PATH_MAX]; |
| 1636 | uint32_t pinning; |
| 1637 | FILE *fp; |
| 1638 | int ret; |
| 1639 | |
| 1640 | fp = fopen(db_file, "r"); |
| 1641 | if (!fp) |
| 1642 | return; |
| 1643 | |
| 1644 | memset(subpath, 0, sizeof(subpath)); |
| 1645 | while ((ret = bpf_read_pin_mapping(fp, &pinning, subpath))) { |
| 1646 | if (ret == -1) { |
| 1647 | fprintf(stderr, "Database %s is corrupted at: %s\n", |
| 1648 | db_file, subpath); |
| 1649 | fclose(fp); |
| 1650 | return; |
| 1651 | } |
| 1652 | |
| 1653 | if (bpf_pinning_reserved(pinning)) { |
Stephen Hemminger | 32a121c | 2016-03-21 11:48:36 -0700 | [diff] [blame] | 1654 | fprintf(stderr, "Database %s, id %u is reserved - ignoring!\n", |
| 1655 | db_file, pinning); |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1656 | continue; |
| 1657 | } |
| 1658 | |
| 1659 | entry = malloc(sizeof(*entry)); |
| 1660 | if (!entry) { |
| 1661 | fprintf(stderr, "No memory left for db entry!\n"); |
| 1662 | continue; |
| 1663 | } |
| 1664 | |
| 1665 | entry->pinning = pinning; |
| 1666 | entry->subpath = strdup(subpath); |
| 1667 | if (!entry->subpath) { |
| 1668 | fprintf(stderr, "No memory left for db entry!\n"); |
| 1669 | free(entry); |
| 1670 | continue; |
| 1671 | } |
| 1672 | |
| 1673 | entry->next = ctx->ht[pinning & (ARRAY_SIZE(ctx->ht) - 1)]; |
| 1674 | ctx->ht[pinning & (ARRAY_SIZE(ctx->ht) - 1)] = entry; |
| 1675 | } |
| 1676 | |
| 1677 | fclose(fp); |
| 1678 | } |
| 1679 | |
| 1680 | static void bpf_hash_destroy(struct bpf_elf_ctx *ctx) |
| 1681 | { |
| 1682 | struct bpf_hash_entry *entry; |
| 1683 | int i; |
| 1684 | |
| 1685 | for (i = 0; i < ARRAY_SIZE(ctx->ht); i++) { |
| 1686 | while ((entry = ctx->ht[i]) != NULL) { |
| 1687 | ctx->ht[i] = entry->next; |
| 1688 | free((char *)entry->subpath); |
| 1689 | free(entry); |
| 1690 | } |
| 1691 | } |
| 1692 | } |
| 1693 | |
Daniel Borkmann | 8187b01 | 2016-01-12 02:03:08 +0100 | [diff] [blame] | 1694 | static int bpf_elf_check_ehdr(const struct bpf_elf_ctx *ctx) |
| 1695 | { |
| 1696 | if (ctx->elf_hdr.e_type != ET_REL || |
Daniel Borkmann | e77fa41 | 2016-07-19 01:09:52 +0200 | [diff] [blame] | 1697 | (ctx->elf_hdr.e_machine != EM_NONE && |
| 1698 | ctx->elf_hdr.e_machine != EM_BPF) || |
Daniel Borkmann | 8187b01 | 2016-01-12 02:03:08 +0100 | [diff] [blame] | 1699 | ctx->elf_hdr.e_version != EV_CURRENT) { |
| 1700 | fprintf(stderr, "ELF format error, ELF file not for eBPF?\n"); |
| 1701 | return -EINVAL; |
| 1702 | } |
| 1703 | |
| 1704 | switch (ctx->elf_hdr.e_ident[EI_DATA]) { |
| 1705 | default: |
| 1706 | fprintf(stderr, "ELF format error, wrong endianness info?\n"); |
| 1707 | return -EINVAL; |
| 1708 | case ELFDATA2LSB: |
| 1709 | if (htons(1) == 1) { |
| 1710 | fprintf(stderr, |
| 1711 | "We are big endian, eBPF object is little endian!\n"); |
| 1712 | return -EIO; |
| 1713 | } |
| 1714 | break; |
| 1715 | case ELFDATA2MSB: |
| 1716 | if (htons(1) != 1) { |
| 1717 | fprintf(stderr, |
| 1718 | "We are little endian, eBPF object is big endian!\n"); |
| 1719 | return -EIO; |
| 1720 | } |
| 1721 | break; |
| 1722 | } |
| 1723 | |
| 1724 | return 0; |
| 1725 | } |
| 1726 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1727 | static int bpf_elf_ctx_init(struct bpf_elf_ctx *ctx, const char *pathname, |
| 1728 | enum bpf_prog_type type, bool verbose) |
| 1729 | { |
| 1730 | int ret = -EINVAL; |
| 1731 | |
| 1732 | if (elf_version(EV_CURRENT) == EV_NONE || |
| 1733 | bpf_init_env(pathname)) |
| 1734 | return ret; |
| 1735 | |
| 1736 | memset(ctx, 0, sizeof(*ctx)); |
| 1737 | ctx->verbose = verbose; |
| 1738 | ctx->type = type; |
| 1739 | |
| 1740 | ctx->obj_fd = open(pathname, O_RDONLY); |
| 1741 | if (ctx->obj_fd < 0) |
| 1742 | return ctx->obj_fd; |
| 1743 | |
| 1744 | ctx->elf_fd = elf_begin(ctx->obj_fd, ELF_C_READ, NULL); |
| 1745 | if (!ctx->elf_fd) { |
| 1746 | ret = -EINVAL; |
| 1747 | goto out_fd; |
| 1748 | } |
| 1749 | |
Daniel Borkmann | 8187b01 | 2016-01-12 02:03:08 +0100 | [diff] [blame] | 1750 | if (elf_kind(ctx->elf_fd) != ELF_K_ELF) { |
| 1751 | ret = -EINVAL; |
| 1752 | goto out_fd; |
| 1753 | } |
| 1754 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1755 | if (gelf_getehdr(ctx->elf_fd, &ctx->elf_hdr) != |
| 1756 | &ctx->elf_hdr) { |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1757 | ret = -EIO; |
| 1758 | goto out_elf; |
| 1759 | } |
| 1760 | |
Daniel Borkmann | 8187b01 | 2016-01-12 02:03:08 +0100 | [diff] [blame] | 1761 | ret = bpf_elf_check_ehdr(ctx); |
| 1762 | if (ret < 0) |
| 1763 | goto out_elf; |
| 1764 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1765 | ctx->sec_done = calloc(ctx->elf_hdr.e_shnum, |
| 1766 | sizeof(*(ctx->sec_done))); |
| 1767 | if (!ctx->sec_done) { |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1768 | ret = -ENOMEM; |
| 1769 | goto out_elf; |
| 1770 | } |
| 1771 | |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1772 | if (ctx->verbose && bpf_log_realloc(ctx)) { |
| 1773 | ret = -ENOMEM; |
| 1774 | goto out_free; |
| 1775 | } |
| 1776 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1777 | bpf_save_finfo(ctx); |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1778 | bpf_hash_init(ctx, CONFDIR "/bpf_pinning"); |
| 1779 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1780 | return 0; |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1781 | out_free: |
| 1782 | free(ctx->sec_done); |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1783 | out_elf: |
| 1784 | elf_end(ctx->elf_fd); |
| 1785 | out_fd: |
| 1786 | close(ctx->obj_fd); |
| 1787 | return ret; |
| 1788 | } |
Daniel Borkmann | d937a74 | 2015-04-28 13:37:42 +0200 | [diff] [blame] | 1789 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1790 | static int bpf_maps_count(struct bpf_elf_ctx *ctx) |
| 1791 | { |
| 1792 | int i, count = 0; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1793 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1794 | for (i = 0; i < ARRAY_SIZE(ctx->map_fds); i++) { |
| 1795 | if (!ctx->map_fds[i]) |
| 1796 | break; |
| 1797 | count++; |
Daniel Borkmann | 473d784 | 2015-05-29 15:15:44 +0200 | [diff] [blame] | 1798 | } |
| 1799 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1800 | return count; |
| 1801 | } |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1802 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1803 | static void bpf_maps_teardown(struct bpf_elf_ctx *ctx) |
| 1804 | { |
| 1805 | int i; |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1806 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1807 | for (i = 0; i < ARRAY_SIZE(ctx->map_fds); i++) { |
| 1808 | if (ctx->map_fds[i]) |
| 1809 | close(ctx->map_fds[i]); |
| 1810 | } |
| 1811 | } |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1812 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1813 | static void bpf_elf_ctx_destroy(struct bpf_elf_ctx *ctx, bool failure) |
| 1814 | { |
| 1815 | if (failure) |
| 1816 | bpf_maps_teardown(ctx); |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1817 | |
Daniel Borkmann | f6793ee | 2015-11-26 15:38:44 +0100 | [diff] [blame] | 1818 | bpf_hash_destroy(ctx); |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1819 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1820 | free(ctx->sec_done); |
Daniel Borkmann | f31645d | 2016-02-07 02:11:51 +0100 | [diff] [blame] | 1821 | free(ctx->log); |
| 1822 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1823 | elf_end(ctx->elf_fd); |
| 1824 | close(ctx->obj_fd); |
| 1825 | } |
| 1826 | |
| 1827 | static struct bpf_elf_ctx __ctx; |
| 1828 | |
| 1829 | static int bpf_obj_open(const char *pathname, enum bpf_prog_type type, |
| 1830 | const char *section, bool verbose) |
| 1831 | { |
| 1832 | struct bpf_elf_ctx *ctx = &__ctx; |
| 1833 | int fd = 0, ret; |
| 1834 | |
| 1835 | ret = bpf_elf_ctx_init(ctx, pathname, type, verbose); |
| 1836 | if (ret < 0) { |
| 1837 | fprintf(stderr, "Cannot initialize ELF context!\n"); |
| 1838 | return ret; |
| 1839 | } |
| 1840 | |
| 1841 | ret = bpf_fetch_ancillary(ctx); |
| 1842 | if (ret < 0) { |
| 1843 | fprintf(stderr, "Error fetching ELF ancillary data!\n"); |
| 1844 | goto out; |
| 1845 | } |
| 1846 | |
| 1847 | fd = bpf_fetch_prog_sec(ctx, section); |
| 1848 | if (fd < 0) { |
| 1849 | fprintf(stderr, "Error fetching program/map!\n"); |
| 1850 | ret = fd; |
| 1851 | goto out; |
| 1852 | } |
| 1853 | |
| 1854 | ret = bpf_fill_prog_arrays(ctx); |
| 1855 | if (ret < 0) |
| 1856 | fprintf(stderr, "Error filling program arrays!\n"); |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1857 | out: |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1858 | bpf_elf_ctx_destroy(ctx, ret < 0); |
| 1859 | if (ret < 0) { |
| 1860 | if (fd) |
| 1861 | close(fd); |
| 1862 | return ret; |
| 1863 | } |
| 1864 | |
| 1865 | return fd; |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 1866 | } |
| 1867 | |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1868 | static int |
Daniel Borkmann | 4bd6244 | 2015-04-16 21:20:06 +0200 | [diff] [blame] | 1869 | bpf_map_set_send(int fd, struct sockaddr_un *addr, unsigned int addr_len, |
| 1870 | const struct bpf_map_data *aux, unsigned int entries) |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1871 | { |
| 1872 | struct bpf_map_set_msg msg; |
| 1873 | int *cmsg_buf, min_fd; |
| 1874 | char *amsg_buf; |
| 1875 | int i; |
| 1876 | |
| 1877 | memset(&msg, 0, sizeof(msg)); |
| 1878 | |
| 1879 | msg.aux.uds_ver = BPF_SCM_AUX_VER; |
Daniel Borkmann | 4bd6244 | 2015-04-16 21:20:06 +0200 | [diff] [blame] | 1880 | msg.aux.num_ent = entries; |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1881 | |
| 1882 | strncpy(msg.aux.obj_name, aux->obj, sizeof(msg.aux.obj_name)); |
| 1883 | memcpy(&msg.aux.obj_st, aux->st, sizeof(msg.aux.obj_st)); |
| 1884 | |
| 1885 | cmsg_buf = bpf_map_set_init(&msg, addr, addr_len); |
| 1886 | amsg_buf = (char *)msg.aux.ent; |
| 1887 | |
Daniel Borkmann | 4bd6244 | 2015-04-16 21:20:06 +0200 | [diff] [blame] | 1888 | for (i = 0; i < entries; i += min_fd) { |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1889 | int ret; |
| 1890 | |
Daniel Borkmann | 4bd6244 | 2015-04-16 21:20:06 +0200 | [diff] [blame] | 1891 | min_fd = min(BPF_SCM_MAX_FDS * 1U, entries - i); |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1892 | bpf_map_set_init_single(&msg, min_fd); |
| 1893 | |
| 1894 | memcpy(cmsg_buf, &aux->fds[i], sizeof(aux->fds[0]) * min_fd); |
| 1895 | memcpy(amsg_buf, &aux->ent[i], sizeof(aux->ent[0]) * min_fd); |
| 1896 | |
| 1897 | ret = sendmsg(fd, &msg.hdr, 0); |
| 1898 | if (ret <= 0) |
| 1899 | return ret ? : -1; |
| 1900 | } |
| 1901 | |
| 1902 | return 0; |
| 1903 | } |
| 1904 | |
Daniel Borkmann | 4bd6244 | 2015-04-16 21:20:06 +0200 | [diff] [blame] | 1905 | static int |
| 1906 | bpf_map_set_recv(int fd, int *fds, struct bpf_map_aux *aux, |
| 1907 | unsigned int entries) |
| 1908 | { |
| 1909 | struct bpf_map_set_msg msg; |
| 1910 | int *cmsg_buf, min_fd; |
| 1911 | char *amsg_buf, *mmsg_buf; |
| 1912 | unsigned int needed = 1; |
| 1913 | int i; |
| 1914 | |
| 1915 | cmsg_buf = bpf_map_set_init(&msg, NULL, 0); |
| 1916 | amsg_buf = (char *)msg.aux.ent; |
| 1917 | mmsg_buf = (char *)&msg.aux; |
| 1918 | |
| 1919 | for (i = 0; i < min(entries, needed); i += min_fd) { |
| 1920 | struct cmsghdr *cmsg; |
| 1921 | int ret; |
| 1922 | |
| 1923 | min_fd = min(entries, entries - i); |
| 1924 | bpf_map_set_init_single(&msg, min_fd); |
| 1925 | |
| 1926 | ret = recvmsg(fd, &msg.hdr, 0); |
| 1927 | if (ret <= 0) |
| 1928 | return ret ? : -1; |
| 1929 | |
| 1930 | cmsg = CMSG_FIRSTHDR(&msg.hdr); |
| 1931 | if (!cmsg || cmsg->cmsg_type != SCM_RIGHTS) |
| 1932 | return -EINVAL; |
| 1933 | if (msg.hdr.msg_flags & MSG_CTRUNC) |
| 1934 | return -EIO; |
| 1935 | if (msg.aux.uds_ver != BPF_SCM_AUX_VER) |
| 1936 | return -ENOSYS; |
| 1937 | |
| 1938 | min_fd = (cmsg->cmsg_len - sizeof(*cmsg)) / sizeof(fd); |
| 1939 | if (min_fd > entries || min_fd <= 0) |
| 1940 | return -EINVAL; |
| 1941 | |
| 1942 | memcpy(&fds[i], cmsg_buf, sizeof(fds[0]) * min_fd); |
| 1943 | memcpy(&aux->ent[i], amsg_buf, sizeof(aux->ent[0]) * min_fd); |
| 1944 | memcpy(aux, mmsg_buf, offsetof(struct bpf_map_aux, ent)); |
| 1945 | |
| 1946 | needed = aux->num_ent; |
| 1947 | } |
| 1948 | |
| 1949 | return 0; |
| 1950 | } |
| 1951 | |
| 1952 | int bpf_send_map_fds(const char *path, const char *obj) |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1953 | { |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1954 | struct bpf_elf_ctx *ctx = &__ctx; |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1955 | struct sockaddr_un addr; |
| 1956 | struct bpf_map_data bpf_aux; |
| 1957 | int fd, ret; |
| 1958 | |
| 1959 | fd = socket(AF_UNIX, SOCK_DGRAM, 0); |
| 1960 | if (fd < 0) { |
| 1961 | fprintf(stderr, "Cannot open socket: %s\n", |
| 1962 | strerror(errno)); |
| 1963 | return -1; |
| 1964 | } |
| 1965 | |
| 1966 | memset(&addr, 0, sizeof(addr)); |
| 1967 | addr.sun_family = AF_UNIX; |
| 1968 | strncpy(addr.sun_path, path, sizeof(addr.sun_path)); |
| 1969 | |
| 1970 | ret = connect(fd, (struct sockaddr *)&addr, sizeof(addr)); |
| 1971 | if (ret < 0) { |
| 1972 | fprintf(stderr, "Cannot connect to %s: %s\n", |
| 1973 | path, strerror(errno)); |
| 1974 | return -1; |
| 1975 | } |
| 1976 | |
| 1977 | memset(&bpf_aux, 0, sizeof(bpf_aux)); |
| 1978 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1979 | bpf_aux.fds = ctx->map_fds; |
| 1980 | bpf_aux.ent = ctx->maps; |
| 1981 | bpf_aux.st = &ctx->stat; |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1982 | bpf_aux.obj = obj; |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1983 | |
Daniel Borkmann | 4bd6244 | 2015-04-16 21:20:06 +0200 | [diff] [blame] | 1984 | ret = bpf_map_set_send(fd, &addr, sizeof(addr), &bpf_aux, |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1985 | bpf_maps_count(ctx)); |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1986 | if (ret < 0) |
Daniel Borkmann | 4bd6244 | 2015-04-16 21:20:06 +0200 | [diff] [blame] | 1987 | fprintf(stderr, "Cannot send fds to %s: %s\n", |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1988 | path, strerror(errno)); |
| 1989 | |
Daniel Borkmann | 32e93fb | 2015-11-13 00:39:29 +0100 | [diff] [blame] | 1990 | bpf_maps_teardown(ctx); |
Daniel Borkmann | 6256f8c | 2015-04-01 17:57:44 +0200 | [diff] [blame] | 1991 | close(fd); |
| 1992 | return ret; |
| 1993 | } |
Daniel Borkmann | 4bd6244 | 2015-04-16 21:20:06 +0200 | [diff] [blame] | 1994 | |
| 1995 | int bpf_recv_map_fds(const char *path, int *fds, struct bpf_map_aux *aux, |
| 1996 | unsigned int entries) |
| 1997 | { |
| 1998 | struct sockaddr_un addr; |
| 1999 | int fd, ret; |
| 2000 | |
| 2001 | fd = socket(AF_UNIX, SOCK_DGRAM, 0); |
| 2002 | if (fd < 0) { |
| 2003 | fprintf(stderr, "Cannot open socket: %s\n", |
| 2004 | strerror(errno)); |
| 2005 | return -1; |
| 2006 | } |
| 2007 | |
| 2008 | memset(&addr, 0, sizeof(addr)); |
| 2009 | addr.sun_family = AF_UNIX; |
| 2010 | strncpy(addr.sun_path, path, sizeof(addr.sun_path)); |
| 2011 | |
| 2012 | ret = bind(fd, (struct sockaddr *)&addr, sizeof(addr)); |
| 2013 | if (ret < 0) { |
| 2014 | fprintf(stderr, "Cannot bind to socket: %s\n", |
| 2015 | strerror(errno)); |
| 2016 | return -1; |
| 2017 | } |
| 2018 | |
| 2019 | ret = bpf_map_set_recv(fd, fds, aux, entries); |
| 2020 | if (ret < 0) |
| 2021 | fprintf(stderr, "Cannot recv fds from %s: %s\n", |
| 2022 | path, strerror(errno)); |
| 2023 | |
| 2024 | unlink(addr.sun_path); |
| 2025 | close(fd); |
| 2026 | return ret; |
| 2027 | } |
Daniel Borkmann | 11c39b5 | 2015-03-16 19:37:41 +0100 | [diff] [blame] | 2028 | #endif /* HAVE_ELF */ |