Commit | Line | Data |
---|---|---|
1b76c13e WN |
1 | /* |
2 | * Common eBPF ELF object loading operations. | |
3 | * | |
4 | * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org> | |
5 | * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com> | |
6 | * Copyright (C) 2015 Huawei Inc. | |
203d1cac WN |
7 | * |
8 | * This program is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU Lesser General Public | |
10 | * License as published by the Free Software Foundation; | |
11 | * version 2.1 of the License (not later!) | |
12 | * | |
13 | * This program is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | * GNU Lesser General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU Lesser General Public | |
19 | * License along with this program; if not, see <http://www.gnu.org/licenses> | |
1b76c13e WN |
20 | */ |
21 | ||
22 | #include <stdlib.h> | |
b3f59d66 WN |
23 | #include <stdio.h> |
24 | #include <stdarg.h> | |
34090915 | 25 | #include <inttypes.h> |
b3f59d66 | 26 | #include <string.h> |
1b76c13e | 27 | #include <unistd.h> |
1a5e3fb1 WN |
28 | #include <fcntl.h> |
29 | #include <errno.h> | |
1b76c13e | 30 | #include <asm/unistd.h> |
cb1e5e96 | 31 | #include <linux/kernel.h> |
1b76c13e | 32 | #include <linux/bpf.h> |
9a208eff | 33 | #include <linux/list.h> |
1a5e3fb1 WN |
34 | #include <libelf.h> |
35 | #include <gelf.h> | |
1b76c13e WN |
36 | |
37 | #include "libbpf.h" | |
52d3352e | 38 | #include "bpf.h" |
b3f59d66 | 39 | |
9b16137a WN |
40 | #ifndef EM_BPF |
41 | #define EM_BPF 247 | |
42 | #endif | |
43 | ||
b3f59d66 WN |
44 | #define __printf(a, b) __attribute__((format(printf, a, b))) |
45 | ||
46 | __printf(1, 2) | |
47 | static int __base_pr(const char *format, ...) | |
48 | { | |
49 | va_list args; | |
50 | int err; | |
51 | ||
52 | va_start(args, format); | |
53 | err = vfprintf(stderr, format, args); | |
54 | va_end(args); | |
55 | return err; | |
56 | } | |
57 | ||
58 | static __printf(1, 2) libbpf_print_fn_t __pr_warning = __base_pr; | |
59 | static __printf(1, 2) libbpf_print_fn_t __pr_info = __base_pr; | |
60 | static __printf(1, 2) libbpf_print_fn_t __pr_debug; | |
61 | ||
62 | #define __pr(func, fmt, ...) \ | |
63 | do { \ | |
64 | if ((func)) \ | |
65 | (func)("libbpf: " fmt, ##__VA_ARGS__); \ | |
66 | } while (0) | |
67 | ||
68 | #define pr_warning(fmt, ...) __pr(__pr_warning, fmt, ##__VA_ARGS__) | |
69 | #define pr_info(fmt, ...) __pr(__pr_info, fmt, ##__VA_ARGS__) | |
70 | #define pr_debug(fmt, ...) __pr(__pr_debug, fmt, ##__VA_ARGS__) | |
71 | ||
72 | void libbpf_set_print(libbpf_print_fn_t warn, | |
73 | libbpf_print_fn_t info, | |
74 | libbpf_print_fn_t debug) | |
75 | { | |
76 | __pr_warning = warn; | |
77 | __pr_info = info; | |
78 | __pr_debug = debug; | |
79 | } | |
1a5e3fb1 | 80 | |
6371ca3b WN |
81 | #define STRERR_BUFSIZE 128 |
82 | ||
83 | #define ERRNO_OFFSET(e) ((e) - __LIBBPF_ERRNO__START) | |
84 | #define ERRCODE_OFFSET(c) ERRNO_OFFSET(LIBBPF_ERRNO__##c) | |
85 | #define NR_ERRNO (__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START) | |
86 | ||
87 | static const char *libbpf_strerror_table[NR_ERRNO] = { | |
88 | [ERRCODE_OFFSET(LIBELF)] = "Something wrong in libelf", | |
89 | [ERRCODE_OFFSET(FORMAT)] = "BPF object format invalid", | |
90 | [ERRCODE_OFFSET(KVERSION)] = "'version' section incorrect or lost", | |
de8a63bd | 91 | [ERRCODE_OFFSET(ENDIAN)] = "Endian mismatch", |
6371ca3b WN |
92 | [ERRCODE_OFFSET(INTERNAL)] = "Internal error in libbpf", |
93 | [ERRCODE_OFFSET(RELOC)] = "Relocation failed", | |
94 | [ERRCODE_OFFSET(VERIFY)] = "Kernel verifier blocks program loading", | |
95 | [ERRCODE_OFFSET(PROG2BIG)] = "Program too big", | |
96 | [ERRCODE_OFFSET(KVER)] = "Incorrect kernel version", | |
705fa219 | 97 | [ERRCODE_OFFSET(PROGTYPE)] = "Kernel doesn't support this program type", |
6371ca3b WN |
98 | }; |
99 | ||
100 | int libbpf_strerror(int err, char *buf, size_t size) | |
101 | { | |
102 | if (!buf || !size) | |
103 | return -1; | |
104 | ||
105 | err = err > 0 ? err : -err; | |
106 | ||
107 | if (err < __LIBBPF_ERRNO__START) { | |
108 | int ret; | |
109 | ||
110 | ret = strerror_r(err, buf, size); | |
111 | buf[size - 1] = '\0'; | |
112 | return ret; | |
113 | } | |
114 | ||
115 | if (err < __LIBBPF_ERRNO__END) { | |
116 | const char *msg; | |
117 | ||
118 | msg = libbpf_strerror_table[ERRNO_OFFSET(err)]; | |
119 | snprintf(buf, size, "%s", msg); | |
120 | buf[size - 1] = '\0'; | |
121 | return 0; | |
122 | } | |
123 | ||
124 | snprintf(buf, size, "Unknown libbpf error %d", err); | |
125 | buf[size - 1] = '\0'; | |
126 | return -1; | |
127 | } | |
128 | ||
129 | #define CHECK_ERR(action, err, out) do { \ | |
130 | err = action; \ | |
131 | if (err) \ | |
132 | goto out; \ | |
133 | } while(0) | |
134 | ||
135 | ||
1a5e3fb1 WN |
136 | /* Copied from tools/perf/util/util.h */ |
137 | #ifndef zfree | |
138 | # define zfree(ptr) ({ free(*ptr); *ptr = NULL; }) | |
139 | #endif | |
140 | ||
141 | #ifndef zclose | |
142 | # define zclose(fd) ({ \ | |
143 | int ___err = 0; \ | |
144 | if ((fd) >= 0) \ | |
145 | ___err = close((fd)); \ | |
146 | fd = -1; \ | |
147 | ___err; }) | |
148 | #endif | |
149 | ||
150 | #ifdef HAVE_LIBELF_MMAP_SUPPORT | |
151 | # define LIBBPF_ELF_C_READ_MMAP ELF_C_READ_MMAP | |
152 | #else | |
153 | # define LIBBPF_ELF_C_READ_MMAP ELF_C_READ | |
154 | #endif | |
155 | ||
a5b8bd47 WN |
156 | /* |
157 | * bpf_prog should be a better name but it has been used in | |
158 | * linux/filter.h. | |
159 | */ | |
160 | struct bpf_program { | |
161 | /* Index in elf obj file, for relocation use. */ | |
162 | int idx; | |
163 | char *section_name; | |
164 | struct bpf_insn *insns; | |
165 | size_t insns_cnt; | |
5f44e4c8 | 166 | enum bpf_prog_type type; |
34090915 WN |
167 | |
168 | struct { | |
169 | int insn_idx; | |
170 | int map_idx; | |
171 | } *reloc_desc; | |
172 | int nr_reloc; | |
55cffde2 | 173 | |
b580563e WN |
174 | struct { |
175 | int nr; | |
176 | int *fds; | |
177 | } instances; | |
178 | bpf_program_prep_t preprocessor; | |
aa9b1ac3 WN |
179 | |
180 | struct bpf_object *obj; | |
181 | void *priv; | |
182 | bpf_program_clear_priv_t clear_priv; | |
a5b8bd47 WN |
183 | }; |
184 | ||
9d759a9b WN |
185 | struct bpf_map { |
186 | int fd; | |
561bbcca | 187 | char *name; |
9d759a9b WN |
188 | struct bpf_map_def def; |
189 | void *priv; | |
190 | bpf_map_clear_priv_t clear_priv; | |
191 | }; | |
192 | ||
9a208eff WN |
193 | static LIST_HEAD(bpf_objects_list); |
194 | ||
1a5e3fb1 | 195 | struct bpf_object { |
cb1e5e96 WN |
196 | char license[64]; |
197 | u32 kern_version; | |
0b3d1efa | 198 | |
a5b8bd47 WN |
199 | struct bpf_program *programs; |
200 | size_t nr_programs; | |
9d759a9b WN |
201 | struct bpf_map *maps; |
202 | size_t nr_maps; | |
203 | ||
52d3352e | 204 | bool loaded; |
a5b8bd47 | 205 | |
1a5e3fb1 WN |
206 | /* |
207 | * Information when doing elf related work. Only valid if fd | |
208 | * is valid. | |
209 | */ | |
210 | struct { | |
211 | int fd; | |
6c956392 WN |
212 | void *obj_buf; |
213 | size_t obj_buf_sz; | |
1a5e3fb1 WN |
214 | Elf *elf; |
215 | GElf_Ehdr ehdr; | |
bec7d68c | 216 | Elf_Data *symbols; |
77ba9a5b | 217 | size_t strtabidx; |
b62f06e8 WN |
218 | struct { |
219 | GElf_Shdr shdr; | |
220 | Elf_Data *data; | |
221 | } *reloc; | |
222 | int nr_reloc; | |
666810e8 | 223 | int maps_shndx; |
1a5e3fb1 | 224 | } efile; |
9a208eff WN |
225 | /* |
226 | * All loaded bpf_object is linked in a list, which is | |
227 | * hidden to caller. bpf_objects__<func> handlers deal with | |
228 | * all objects. | |
229 | */ | |
230 | struct list_head list; | |
1a5e3fb1 WN |
231 | char path[]; |
232 | }; | |
233 | #define obj_elf_valid(o) ((o)->efile.elf) | |
234 | ||
55cffde2 WN |
235 | static void bpf_program__unload(struct bpf_program *prog) |
236 | { | |
b580563e WN |
237 | int i; |
238 | ||
55cffde2 WN |
239 | if (!prog) |
240 | return; | |
241 | ||
b580563e WN |
242 | /* |
243 | * If the object is opened but the program was never loaded, | |
244 | * it is possible that prog->instances.nr == -1. | |
245 | */ | |
246 | if (prog->instances.nr > 0) { | |
247 | for (i = 0; i < prog->instances.nr; i++) | |
248 | zclose(prog->instances.fds[i]); | |
249 | } else if (prog->instances.nr != -1) { | |
250 | pr_warning("Internal error: instances.nr is %d\n", | |
251 | prog->instances.nr); | |
252 | } | |
253 | ||
254 | prog->instances.nr = -1; | |
255 | zfree(&prog->instances.fds); | |
55cffde2 WN |
256 | } |
257 | ||
a5b8bd47 WN |
258 | static void bpf_program__exit(struct bpf_program *prog) |
259 | { | |
260 | if (!prog) | |
261 | return; | |
262 | ||
aa9b1ac3 WN |
263 | if (prog->clear_priv) |
264 | prog->clear_priv(prog, prog->priv); | |
265 | ||
266 | prog->priv = NULL; | |
267 | prog->clear_priv = NULL; | |
268 | ||
55cffde2 | 269 | bpf_program__unload(prog); |
a5b8bd47 WN |
270 | zfree(&prog->section_name); |
271 | zfree(&prog->insns); | |
34090915 WN |
272 | zfree(&prog->reloc_desc); |
273 | ||
274 | prog->nr_reloc = 0; | |
a5b8bd47 WN |
275 | prog->insns_cnt = 0; |
276 | prog->idx = -1; | |
277 | } | |
278 | ||
279 | static int | |
280 | bpf_program__init(void *data, size_t size, char *name, int idx, | |
281 | struct bpf_program *prog) | |
282 | { | |
283 | if (size < sizeof(struct bpf_insn)) { | |
284 | pr_warning("corrupted section '%s'\n", name); | |
285 | return -EINVAL; | |
286 | } | |
287 | ||
288 | bzero(prog, sizeof(*prog)); | |
289 | ||
290 | prog->section_name = strdup(name); | |
291 | if (!prog->section_name) { | |
292 | pr_warning("failed to alloc name for prog %s\n", | |
293 | name); | |
294 | goto errout; | |
295 | } | |
296 | ||
297 | prog->insns = malloc(size); | |
298 | if (!prog->insns) { | |
299 | pr_warning("failed to alloc insns for %s\n", name); | |
300 | goto errout; | |
301 | } | |
302 | prog->insns_cnt = size / sizeof(struct bpf_insn); | |
303 | memcpy(prog->insns, data, | |
304 | prog->insns_cnt * sizeof(struct bpf_insn)); | |
305 | prog->idx = idx; | |
b580563e WN |
306 | prog->instances.fds = NULL; |
307 | prog->instances.nr = -1; | |
5f44e4c8 | 308 | prog->type = BPF_PROG_TYPE_KPROBE; |
a5b8bd47 WN |
309 | |
310 | return 0; | |
311 | errout: | |
312 | bpf_program__exit(prog); | |
313 | return -ENOMEM; | |
314 | } | |
315 | ||
316 | static int | |
317 | bpf_object__add_program(struct bpf_object *obj, void *data, size_t size, | |
318 | char *name, int idx) | |
319 | { | |
320 | struct bpf_program prog, *progs; | |
321 | int nr_progs, err; | |
322 | ||
323 | err = bpf_program__init(data, size, name, idx, &prog); | |
324 | if (err) | |
325 | return err; | |
326 | ||
327 | progs = obj->programs; | |
328 | nr_progs = obj->nr_programs; | |
329 | ||
330 | progs = realloc(progs, sizeof(progs[0]) * (nr_progs + 1)); | |
331 | if (!progs) { | |
332 | /* | |
333 | * In this case the original obj->programs | |
334 | * is still valid, so don't need special treat for | |
335 | * bpf_close_object(). | |
336 | */ | |
337 | pr_warning("failed to alloc a new program '%s'\n", | |
338 | name); | |
339 | bpf_program__exit(&prog); | |
340 | return -ENOMEM; | |
341 | } | |
342 | ||
343 | pr_debug("found program %s\n", prog.section_name); | |
344 | obj->programs = progs; | |
345 | obj->nr_programs = nr_progs + 1; | |
aa9b1ac3 | 346 | prog.obj = obj; |
a5b8bd47 WN |
347 | progs[nr_progs] = prog; |
348 | return 0; | |
349 | } | |
350 | ||
6c956392 WN |
351 | static struct bpf_object *bpf_object__new(const char *path, |
352 | void *obj_buf, | |
353 | size_t obj_buf_sz) | |
1a5e3fb1 WN |
354 | { |
355 | struct bpf_object *obj; | |
356 | ||
357 | obj = calloc(1, sizeof(struct bpf_object) + strlen(path) + 1); | |
358 | if (!obj) { | |
359 | pr_warning("alloc memory failed for %s\n", path); | |
6371ca3b | 360 | return ERR_PTR(-ENOMEM); |
1a5e3fb1 WN |
361 | } |
362 | ||
363 | strcpy(obj->path, path); | |
364 | obj->efile.fd = -1; | |
6c956392 WN |
365 | |
366 | /* | |
367 | * Caller of this function should also calls | |
368 | * bpf_object__elf_finish() after data collection to return | |
369 | * obj_buf to user. If not, we should duplicate the buffer to | |
370 | * avoid user freeing them before elf finish. | |
371 | */ | |
372 | obj->efile.obj_buf = obj_buf; | |
373 | obj->efile.obj_buf_sz = obj_buf_sz; | |
666810e8 | 374 | obj->efile.maps_shndx = -1; |
6c956392 | 375 | |
52d3352e | 376 | obj->loaded = false; |
9a208eff WN |
377 | |
378 | INIT_LIST_HEAD(&obj->list); | |
379 | list_add(&obj->list, &bpf_objects_list); | |
1a5e3fb1 WN |
380 | return obj; |
381 | } | |
382 | ||
383 | static void bpf_object__elf_finish(struct bpf_object *obj) | |
384 | { | |
385 | if (!obj_elf_valid(obj)) | |
386 | return; | |
387 | ||
388 | if (obj->efile.elf) { | |
389 | elf_end(obj->efile.elf); | |
390 | obj->efile.elf = NULL; | |
391 | } | |
bec7d68c | 392 | obj->efile.symbols = NULL; |
b62f06e8 WN |
393 | |
394 | zfree(&obj->efile.reloc); | |
395 | obj->efile.nr_reloc = 0; | |
1a5e3fb1 | 396 | zclose(obj->efile.fd); |
6c956392 WN |
397 | obj->efile.obj_buf = NULL; |
398 | obj->efile.obj_buf_sz = 0; | |
1a5e3fb1 WN |
399 | } |
400 | ||
401 | static int bpf_object__elf_init(struct bpf_object *obj) | |
402 | { | |
403 | int err = 0; | |
404 | GElf_Ehdr *ep; | |
405 | ||
406 | if (obj_elf_valid(obj)) { | |
407 | pr_warning("elf init: internal error\n"); | |
6371ca3b | 408 | return -LIBBPF_ERRNO__LIBELF; |
1a5e3fb1 WN |
409 | } |
410 | ||
6c956392 WN |
411 | if (obj->efile.obj_buf_sz > 0) { |
412 | /* | |
413 | * obj_buf should have been validated by | |
414 | * bpf_object__open_buffer(). | |
415 | */ | |
416 | obj->efile.elf = elf_memory(obj->efile.obj_buf, | |
417 | obj->efile.obj_buf_sz); | |
418 | } else { | |
419 | obj->efile.fd = open(obj->path, O_RDONLY); | |
420 | if (obj->efile.fd < 0) { | |
421 | pr_warning("failed to open %s: %s\n", obj->path, | |
422 | strerror(errno)); | |
423 | return -errno; | |
424 | } | |
425 | ||
426 | obj->efile.elf = elf_begin(obj->efile.fd, | |
427 | LIBBPF_ELF_C_READ_MMAP, | |
428 | NULL); | |
1a5e3fb1 WN |
429 | } |
430 | ||
1a5e3fb1 WN |
431 | if (!obj->efile.elf) { |
432 | pr_warning("failed to open %s as ELF file\n", | |
433 | obj->path); | |
6371ca3b | 434 | err = -LIBBPF_ERRNO__LIBELF; |
1a5e3fb1 WN |
435 | goto errout; |
436 | } | |
437 | ||
438 | if (!gelf_getehdr(obj->efile.elf, &obj->efile.ehdr)) { | |
439 | pr_warning("failed to get EHDR from %s\n", | |
440 | obj->path); | |
6371ca3b | 441 | err = -LIBBPF_ERRNO__FORMAT; |
1a5e3fb1 WN |
442 | goto errout; |
443 | } | |
444 | ep = &obj->efile.ehdr; | |
445 | ||
9b16137a WN |
446 | /* Old LLVM set e_machine to EM_NONE */ |
447 | if ((ep->e_type != ET_REL) || (ep->e_machine && (ep->e_machine != EM_BPF))) { | |
1a5e3fb1 WN |
448 | pr_warning("%s is not an eBPF object file\n", |
449 | obj->path); | |
6371ca3b | 450 | err = -LIBBPF_ERRNO__FORMAT; |
1a5e3fb1 WN |
451 | goto errout; |
452 | } | |
453 | ||
454 | return 0; | |
455 | errout: | |
456 | bpf_object__elf_finish(obj); | |
457 | return err; | |
458 | } | |
459 | ||
cc4228d5 WN |
460 | static int |
461 | bpf_object__check_endianness(struct bpf_object *obj) | |
462 | { | |
463 | static unsigned int const endian = 1; | |
464 | ||
465 | switch (obj->efile.ehdr.e_ident[EI_DATA]) { | |
466 | case ELFDATA2LSB: | |
467 | /* We are big endian, BPF obj is little endian. */ | |
468 | if (*(unsigned char const *)&endian != 1) | |
469 | goto mismatch; | |
470 | break; | |
471 | ||
472 | case ELFDATA2MSB: | |
473 | /* We are little endian, BPF obj is big endian. */ | |
474 | if (*(unsigned char const *)&endian != 0) | |
475 | goto mismatch; | |
476 | break; | |
477 | default: | |
6371ca3b | 478 | return -LIBBPF_ERRNO__ENDIAN; |
cc4228d5 WN |
479 | } |
480 | ||
481 | return 0; | |
482 | ||
483 | mismatch: | |
484 | pr_warning("Error: endianness mismatch.\n"); | |
6371ca3b | 485 | return -LIBBPF_ERRNO__ENDIAN; |
cc4228d5 WN |
486 | } |
487 | ||
cb1e5e96 WN |
488 | static int |
489 | bpf_object__init_license(struct bpf_object *obj, | |
490 | void *data, size_t size) | |
491 | { | |
492 | memcpy(obj->license, data, | |
493 | min(size, sizeof(obj->license) - 1)); | |
494 | pr_debug("license of %s is %s\n", obj->path, obj->license); | |
495 | return 0; | |
496 | } | |
497 | ||
498 | static int | |
499 | bpf_object__init_kversion(struct bpf_object *obj, | |
500 | void *data, size_t size) | |
501 | { | |
502 | u32 kver; | |
503 | ||
504 | if (size != sizeof(kver)) { | |
505 | pr_warning("invalid kver section in %s\n", obj->path); | |
6371ca3b | 506 | return -LIBBPF_ERRNO__FORMAT; |
cb1e5e96 WN |
507 | } |
508 | memcpy(&kver, data, sizeof(kver)); | |
509 | obj->kern_version = kver; | |
510 | pr_debug("kernel version of %s is %x\n", obj->path, | |
511 | obj->kern_version); | |
512 | return 0; | |
513 | } | |
514 | ||
0b3d1efa WN |
515 | static int |
516 | bpf_object__init_maps(struct bpf_object *obj, void *data, | |
517 | size_t size) | |
518 | { | |
9d759a9b WN |
519 | size_t nr_maps; |
520 | int i; | |
521 | ||
522 | nr_maps = size / sizeof(struct bpf_map_def); | |
523 | if (!data || !nr_maps) { | |
0b3d1efa WN |
524 | pr_debug("%s doesn't need map definition\n", |
525 | obj->path); | |
526 | return 0; | |
527 | } | |
528 | ||
9d759a9b WN |
529 | pr_debug("maps in %s: %zd bytes\n", obj->path, size); |
530 | ||
531 | obj->maps = calloc(nr_maps, sizeof(obj->maps[0])); | |
532 | if (!obj->maps) { | |
533 | pr_warning("alloc maps for object failed\n"); | |
0b3d1efa WN |
534 | return -ENOMEM; |
535 | } | |
9d759a9b WN |
536 | obj->nr_maps = nr_maps; |
537 | ||
538 | for (i = 0; i < nr_maps; i++) { | |
539 | struct bpf_map_def *def = &obj->maps[i].def; | |
0b3d1efa | 540 | |
9d759a9b WN |
541 | /* |
542 | * fill all fd with -1 so won't close incorrect | |
543 | * fd (fd=0 is stdin) when failure (zclose won't close | |
544 | * negative fd)). | |
545 | */ | |
546 | obj->maps[i].fd = -1; | |
547 | ||
548 | /* Save map definition into obj->maps */ | |
549 | *def = ((struct bpf_map_def *)data)[i]; | |
550 | } | |
0b3d1efa WN |
551 | return 0; |
552 | } | |
553 | ||
973170e6 | 554 | static int |
666810e8 | 555 | bpf_object__init_maps_name(struct bpf_object *obj) |
561bbcca WN |
556 | { |
557 | int i; | |
558 | Elf_Data *symbols = obj->efile.symbols; | |
559 | ||
666810e8 | 560 | if (!symbols || obj->efile.maps_shndx < 0) |
973170e6 | 561 | return -EINVAL; |
561bbcca WN |
562 | |
563 | for (i = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) { | |
564 | GElf_Sym sym; | |
565 | size_t map_idx; | |
566 | const char *map_name; | |
567 | ||
568 | if (!gelf_getsym(symbols, i, &sym)) | |
569 | continue; | |
666810e8 | 570 | if (sym.st_shndx != obj->efile.maps_shndx) |
561bbcca WN |
571 | continue; |
572 | ||
573 | map_name = elf_strptr(obj->efile.elf, | |
77ba9a5b | 574 | obj->efile.strtabidx, |
561bbcca WN |
575 | sym.st_name); |
576 | map_idx = sym.st_value / sizeof(struct bpf_map_def); | |
577 | if (map_idx >= obj->nr_maps) { | |
578 | pr_warning("index of map \"%s\" is buggy: %zu > %zu\n", | |
579 | map_name, map_idx, obj->nr_maps); | |
580 | continue; | |
581 | } | |
582 | obj->maps[map_idx].name = strdup(map_name); | |
973170e6 WN |
583 | if (!obj->maps[map_idx].name) { |
584 | pr_warning("failed to alloc map name\n"); | |
585 | return -ENOMEM; | |
586 | } | |
561bbcca WN |
587 | pr_debug("map %zu is \"%s\"\n", map_idx, |
588 | obj->maps[map_idx].name); | |
589 | } | |
973170e6 | 590 | return 0; |
561bbcca WN |
591 | } |
592 | ||
29603665 WN |
593 | static int bpf_object__elf_collect(struct bpf_object *obj) |
594 | { | |
595 | Elf *elf = obj->efile.elf; | |
596 | GElf_Ehdr *ep = &obj->efile.ehdr; | |
597 | Elf_Scn *scn = NULL; | |
666810e8 | 598 | int idx = 0, err = 0; |
29603665 WN |
599 | |
600 | /* Elf is corrupted/truncated, avoid calling elf_strptr. */ | |
601 | if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) { | |
602 | pr_warning("failed to get e_shstrndx from %s\n", | |
603 | obj->path); | |
6371ca3b | 604 | return -LIBBPF_ERRNO__FORMAT; |
29603665 WN |
605 | } |
606 | ||
607 | while ((scn = elf_nextscn(elf, scn)) != NULL) { | |
608 | char *name; | |
609 | GElf_Shdr sh; | |
610 | Elf_Data *data; | |
611 | ||
612 | idx++; | |
613 | if (gelf_getshdr(scn, &sh) != &sh) { | |
614 | pr_warning("failed to get section header from %s\n", | |
615 | obj->path); | |
6371ca3b | 616 | err = -LIBBPF_ERRNO__FORMAT; |
29603665 WN |
617 | goto out; |
618 | } | |
619 | ||
620 | name = elf_strptr(elf, ep->e_shstrndx, sh.sh_name); | |
621 | if (!name) { | |
622 | pr_warning("failed to get section name from %s\n", | |
623 | obj->path); | |
6371ca3b | 624 | err = -LIBBPF_ERRNO__FORMAT; |
29603665 WN |
625 | goto out; |
626 | } | |
627 | ||
628 | data = elf_getdata(scn, 0); | |
629 | if (!data) { | |
630 | pr_warning("failed to get section data from %s(%s)\n", | |
631 | name, obj->path); | |
6371ca3b | 632 | err = -LIBBPF_ERRNO__FORMAT; |
29603665 WN |
633 | goto out; |
634 | } | |
635 | pr_debug("section %s, size %ld, link %d, flags %lx, type=%d\n", | |
636 | name, (unsigned long)data->d_size, | |
637 | (int)sh.sh_link, (unsigned long)sh.sh_flags, | |
638 | (int)sh.sh_type); | |
cb1e5e96 WN |
639 | |
640 | if (strcmp(name, "license") == 0) | |
641 | err = bpf_object__init_license(obj, | |
642 | data->d_buf, | |
643 | data->d_size); | |
644 | else if (strcmp(name, "version") == 0) | |
645 | err = bpf_object__init_kversion(obj, | |
646 | data->d_buf, | |
647 | data->d_size); | |
561bbcca | 648 | else if (strcmp(name, "maps") == 0) { |
0b3d1efa WN |
649 | err = bpf_object__init_maps(obj, data->d_buf, |
650 | data->d_size); | |
666810e8 | 651 | obj->efile.maps_shndx = idx; |
561bbcca | 652 | } else if (sh.sh_type == SHT_SYMTAB) { |
bec7d68c WN |
653 | if (obj->efile.symbols) { |
654 | pr_warning("bpf: multiple SYMTAB in %s\n", | |
655 | obj->path); | |
6371ca3b | 656 | err = -LIBBPF_ERRNO__FORMAT; |
77ba9a5b | 657 | } else { |
bec7d68c | 658 | obj->efile.symbols = data; |
77ba9a5b WN |
659 | obj->efile.strtabidx = sh.sh_link; |
660 | } | |
a5b8bd47 WN |
661 | } else if ((sh.sh_type == SHT_PROGBITS) && |
662 | (sh.sh_flags & SHF_EXECINSTR) && | |
663 | (data->d_size > 0)) { | |
664 | err = bpf_object__add_program(obj, data->d_buf, | |
665 | data->d_size, name, idx); | |
666 | if (err) { | |
6371ca3b WN |
667 | char errmsg[STRERR_BUFSIZE]; |
668 | ||
a5b8bd47 WN |
669 | strerror_r(-err, errmsg, sizeof(errmsg)); |
670 | pr_warning("failed to alloc program %s (%s): %s", | |
671 | name, obj->path, errmsg); | |
672 | } | |
b62f06e8 WN |
673 | } else if (sh.sh_type == SHT_REL) { |
674 | void *reloc = obj->efile.reloc; | |
675 | int nr_reloc = obj->efile.nr_reloc + 1; | |
676 | ||
677 | reloc = realloc(reloc, | |
678 | sizeof(*obj->efile.reloc) * nr_reloc); | |
679 | if (!reloc) { | |
680 | pr_warning("realloc failed\n"); | |
681 | err = -ENOMEM; | |
682 | } else { | |
683 | int n = nr_reloc - 1; | |
684 | ||
685 | obj->efile.reloc = reloc; | |
686 | obj->efile.nr_reloc = nr_reloc; | |
687 | ||
688 | obj->efile.reloc[n].shdr = sh; | |
689 | obj->efile.reloc[n].data = data; | |
690 | } | |
bec7d68c | 691 | } |
cb1e5e96 WN |
692 | if (err) |
693 | goto out; | |
29603665 | 694 | } |
561bbcca | 695 | |
77ba9a5b WN |
696 | if (!obj->efile.strtabidx || obj->efile.strtabidx >= idx) { |
697 | pr_warning("Corrupted ELF file: index of strtab invalid\n"); | |
698 | return LIBBPF_ERRNO__FORMAT; | |
699 | } | |
666810e8 WN |
700 | if (obj->efile.maps_shndx >= 0) |
701 | err = bpf_object__init_maps_name(obj); | |
29603665 WN |
702 | out: |
703 | return err; | |
704 | } | |
705 | ||
34090915 WN |
706 | static struct bpf_program * |
707 | bpf_object__find_prog_by_idx(struct bpf_object *obj, int idx) | |
708 | { | |
709 | struct bpf_program *prog; | |
710 | size_t i; | |
711 | ||
712 | for (i = 0; i < obj->nr_programs; i++) { | |
713 | prog = &obj->programs[i]; | |
714 | if (prog->idx == idx) | |
715 | return prog; | |
716 | } | |
717 | return NULL; | |
718 | } | |
719 | ||
720 | static int | |
721 | bpf_program__collect_reloc(struct bpf_program *prog, | |
722 | size_t nr_maps, GElf_Shdr *shdr, | |
666810e8 WN |
723 | Elf_Data *data, Elf_Data *symbols, |
724 | int maps_shndx) | |
34090915 WN |
725 | { |
726 | int i, nrels; | |
727 | ||
728 | pr_debug("collecting relocating info for: '%s'\n", | |
729 | prog->section_name); | |
730 | nrels = shdr->sh_size / shdr->sh_entsize; | |
731 | ||
732 | prog->reloc_desc = malloc(sizeof(*prog->reloc_desc) * nrels); | |
733 | if (!prog->reloc_desc) { | |
734 | pr_warning("failed to alloc memory in relocation\n"); | |
735 | return -ENOMEM; | |
736 | } | |
737 | prog->nr_reloc = nrels; | |
738 | ||
739 | for (i = 0; i < nrels; i++) { | |
740 | GElf_Sym sym; | |
741 | GElf_Rel rel; | |
742 | unsigned int insn_idx; | |
743 | struct bpf_insn *insns = prog->insns; | |
744 | size_t map_idx; | |
745 | ||
746 | if (!gelf_getrel(data, i, &rel)) { | |
747 | pr_warning("relocation: failed to get %d reloc\n", i); | |
6371ca3b | 748 | return -LIBBPF_ERRNO__FORMAT; |
34090915 WN |
749 | } |
750 | ||
34090915 WN |
751 | if (!gelf_getsym(symbols, |
752 | GELF_R_SYM(rel.r_info), | |
753 | &sym)) { | |
754 | pr_warning("relocation: symbol %"PRIx64" not found\n", | |
755 | GELF_R_SYM(rel.r_info)); | |
6371ca3b | 756 | return -LIBBPF_ERRNO__FORMAT; |
34090915 WN |
757 | } |
758 | ||
666810e8 WN |
759 | if (sym.st_shndx != maps_shndx) { |
760 | pr_warning("Program '%s' contains non-map related relo data pointing to section %u\n", | |
761 | prog->section_name, sym.st_shndx); | |
762 | return -LIBBPF_ERRNO__RELOC; | |
763 | } | |
764 | ||
765 | insn_idx = rel.r_offset / sizeof(struct bpf_insn); | |
766 | pr_debug("relocation: insn_idx=%u\n", insn_idx); | |
767 | ||
34090915 WN |
768 | if (insns[insn_idx].code != (BPF_LD | BPF_IMM | BPF_DW)) { |
769 | pr_warning("bpf: relocation: invalid relo for insns[%d].code 0x%x\n", | |
770 | insn_idx, insns[insn_idx].code); | |
6371ca3b | 771 | return -LIBBPF_ERRNO__RELOC; |
34090915 WN |
772 | } |
773 | ||
774 | map_idx = sym.st_value / sizeof(struct bpf_map_def); | |
775 | if (map_idx >= nr_maps) { | |
776 | pr_warning("bpf relocation: map_idx %d large than %d\n", | |
777 | (int)map_idx, (int)nr_maps - 1); | |
6371ca3b | 778 | return -LIBBPF_ERRNO__RELOC; |
34090915 WN |
779 | } |
780 | ||
781 | prog->reloc_desc[i].insn_idx = insn_idx; | |
782 | prog->reloc_desc[i].map_idx = map_idx; | |
783 | } | |
784 | return 0; | |
785 | } | |
786 | ||
52d3352e WN |
787 | static int |
788 | bpf_object__create_maps(struct bpf_object *obj) | |
789 | { | |
790 | unsigned int i; | |
52d3352e | 791 | |
9d759a9b WN |
792 | for (i = 0; i < obj->nr_maps; i++) { |
793 | struct bpf_map_def *def = &obj->maps[i].def; | |
794 | int *pfd = &obj->maps[i].fd; | |
52d3352e | 795 | |
9d759a9b WN |
796 | *pfd = bpf_create_map(def->type, |
797 | def->key_size, | |
798 | def->value_size, | |
799 | def->max_entries); | |
52d3352e WN |
800 | if (*pfd < 0) { |
801 | size_t j; | |
802 | int err = *pfd; | |
803 | ||
804 | pr_warning("failed to create map: %s\n", | |
805 | strerror(errno)); | |
806 | for (j = 0; j < i; j++) | |
9d759a9b | 807 | zclose(obj->maps[j].fd); |
52d3352e WN |
808 | return err; |
809 | } | |
810 | pr_debug("create map: fd=%d\n", *pfd); | |
52d3352e WN |
811 | } |
812 | ||
52d3352e WN |
813 | return 0; |
814 | } | |
815 | ||
8a47a6c5 | 816 | static int |
9d759a9b | 817 | bpf_program__relocate(struct bpf_program *prog, struct bpf_object *obj) |
8a47a6c5 WN |
818 | { |
819 | int i; | |
820 | ||
821 | if (!prog || !prog->reloc_desc) | |
822 | return 0; | |
823 | ||
824 | for (i = 0; i < prog->nr_reloc; i++) { | |
825 | int insn_idx, map_idx; | |
826 | struct bpf_insn *insns = prog->insns; | |
827 | ||
828 | insn_idx = prog->reloc_desc[i].insn_idx; | |
829 | map_idx = prog->reloc_desc[i].map_idx; | |
830 | ||
831 | if (insn_idx >= (int)prog->insns_cnt) { | |
832 | pr_warning("relocation out of range: '%s'\n", | |
833 | prog->section_name); | |
6371ca3b | 834 | return -LIBBPF_ERRNO__RELOC; |
8a47a6c5 WN |
835 | } |
836 | insns[insn_idx].src_reg = BPF_PSEUDO_MAP_FD; | |
9d759a9b | 837 | insns[insn_idx].imm = obj->maps[map_idx].fd; |
8a47a6c5 WN |
838 | } |
839 | ||
840 | zfree(&prog->reloc_desc); | |
841 | prog->nr_reloc = 0; | |
842 | return 0; | |
843 | } | |
844 | ||
845 | ||
846 | static int | |
847 | bpf_object__relocate(struct bpf_object *obj) | |
848 | { | |
849 | struct bpf_program *prog; | |
850 | size_t i; | |
851 | int err; | |
852 | ||
853 | for (i = 0; i < obj->nr_programs; i++) { | |
854 | prog = &obj->programs[i]; | |
855 | ||
9d759a9b | 856 | err = bpf_program__relocate(prog, obj); |
8a47a6c5 WN |
857 | if (err) { |
858 | pr_warning("failed to relocate '%s'\n", | |
859 | prog->section_name); | |
860 | return err; | |
861 | } | |
862 | } | |
863 | return 0; | |
864 | } | |
865 | ||
34090915 WN |
866 | static int bpf_object__collect_reloc(struct bpf_object *obj) |
867 | { | |
868 | int i, err; | |
869 | ||
870 | if (!obj_elf_valid(obj)) { | |
871 | pr_warning("Internal error: elf object is closed\n"); | |
6371ca3b | 872 | return -LIBBPF_ERRNO__INTERNAL; |
34090915 WN |
873 | } |
874 | ||
875 | for (i = 0; i < obj->efile.nr_reloc; i++) { | |
876 | GElf_Shdr *shdr = &obj->efile.reloc[i].shdr; | |
877 | Elf_Data *data = obj->efile.reloc[i].data; | |
878 | int idx = shdr->sh_info; | |
879 | struct bpf_program *prog; | |
9d759a9b | 880 | size_t nr_maps = obj->nr_maps; |
34090915 WN |
881 | |
882 | if (shdr->sh_type != SHT_REL) { | |
883 | pr_warning("internal error at %d\n", __LINE__); | |
6371ca3b | 884 | return -LIBBPF_ERRNO__INTERNAL; |
34090915 WN |
885 | } |
886 | ||
887 | prog = bpf_object__find_prog_by_idx(obj, idx); | |
888 | if (!prog) { | |
889 | pr_warning("relocation failed: no %d section\n", | |
890 | idx); | |
6371ca3b | 891 | return -LIBBPF_ERRNO__RELOC; |
34090915 WN |
892 | } |
893 | ||
894 | err = bpf_program__collect_reloc(prog, nr_maps, | |
895 | shdr, data, | |
666810e8 WN |
896 | obj->efile.symbols, |
897 | obj->efile.maps_shndx); | |
34090915 | 898 | if (err) |
6371ca3b | 899 | return err; |
34090915 WN |
900 | } |
901 | return 0; | |
902 | } | |
903 | ||
55cffde2 | 904 | static int |
5f44e4c8 WN |
905 | load_program(enum bpf_prog_type type, struct bpf_insn *insns, |
906 | int insns_cnt, char *license, u32 kern_version, int *pfd) | |
55cffde2 WN |
907 | { |
908 | int ret; | |
909 | char *log_buf; | |
910 | ||
911 | if (!insns || !insns_cnt) | |
912 | return -EINVAL; | |
913 | ||
914 | log_buf = malloc(BPF_LOG_BUF_SIZE); | |
915 | if (!log_buf) | |
916 | pr_warning("Alloc log buffer for bpf loader error, continue without log\n"); | |
917 | ||
5f44e4c8 WN |
918 | ret = bpf_load_program(type, insns, insns_cnt, license, |
919 | kern_version, log_buf, BPF_LOG_BUF_SIZE); | |
55cffde2 WN |
920 | |
921 | if (ret >= 0) { | |
922 | *pfd = ret; | |
923 | ret = 0; | |
924 | goto out; | |
925 | } | |
926 | ||
6371ca3b | 927 | ret = -LIBBPF_ERRNO__LOAD; |
55cffde2 WN |
928 | pr_warning("load bpf program failed: %s\n", strerror(errno)); |
929 | ||
6371ca3b WN |
930 | if (log_buf && log_buf[0] != '\0') { |
931 | ret = -LIBBPF_ERRNO__VERIFY; | |
55cffde2 WN |
932 | pr_warning("-- BEGIN DUMP LOG ---\n"); |
933 | pr_warning("\n%s\n", log_buf); | |
934 | pr_warning("-- END LOG --\n"); | |
705fa219 WN |
935 | } else if (insns_cnt >= BPF_MAXINSNS) { |
936 | pr_warning("Program too large (%d insns), at most %d insns\n", | |
937 | insns_cnt, BPF_MAXINSNS); | |
938 | ret = -LIBBPF_ERRNO__PROG2BIG; | |
6371ca3b | 939 | } else { |
705fa219 WN |
940 | /* Wrong program type? */ |
941 | if (type != BPF_PROG_TYPE_KPROBE) { | |
942 | int fd; | |
943 | ||
944 | fd = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns, | |
945 | insns_cnt, license, kern_version, | |
946 | NULL, 0); | |
947 | if (fd >= 0) { | |
948 | close(fd); | |
949 | ret = -LIBBPF_ERRNO__PROGTYPE; | |
950 | goto out; | |
951 | } | |
6371ca3b | 952 | } |
705fa219 WN |
953 | |
954 | if (log_buf) | |
955 | ret = -LIBBPF_ERRNO__KVER; | |
55cffde2 WN |
956 | } |
957 | ||
958 | out: | |
959 | free(log_buf); | |
960 | return ret; | |
961 | } | |
962 | ||
963 | static int | |
964 | bpf_program__load(struct bpf_program *prog, | |
965 | char *license, u32 kern_version) | |
966 | { | |
b580563e | 967 | int err = 0, fd, i; |
55cffde2 | 968 | |
b580563e WN |
969 | if (prog->instances.nr < 0 || !prog->instances.fds) { |
970 | if (prog->preprocessor) { | |
971 | pr_warning("Internal error: can't load program '%s'\n", | |
972 | prog->section_name); | |
973 | return -LIBBPF_ERRNO__INTERNAL; | |
974 | } | |
55cffde2 | 975 | |
b580563e WN |
976 | prog->instances.fds = malloc(sizeof(int)); |
977 | if (!prog->instances.fds) { | |
978 | pr_warning("Not enough memory for BPF fds\n"); | |
979 | return -ENOMEM; | |
980 | } | |
981 | prog->instances.nr = 1; | |
982 | prog->instances.fds[0] = -1; | |
983 | } | |
984 | ||
985 | if (!prog->preprocessor) { | |
986 | if (prog->instances.nr != 1) { | |
987 | pr_warning("Program '%s' is inconsistent: nr(%d) != 1\n", | |
988 | prog->section_name, prog->instances.nr); | |
989 | } | |
5f44e4c8 | 990 | err = load_program(prog->type, prog->insns, prog->insns_cnt, |
b580563e WN |
991 | license, kern_version, &fd); |
992 | if (!err) | |
993 | prog->instances.fds[0] = fd; | |
994 | goto out; | |
995 | } | |
996 | ||
997 | for (i = 0; i < prog->instances.nr; i++) { | |
998 | struct bpf_prog_prep_result result; | |
999 | bpf_program_prep_t preprocessor = prog->preprocessor; | |
1000 | ||
1001 | bzero(&result, sizeof(result)); | |
1002 | err = preprocessor(prog, i, prog->insns, | |
1003 | prog->insns_cnt, &result); | |
1004 | if (err) { | |
1005 | pr_warning("Preprocessing the %dth instance of program '%s' failed\n", | |
1006 | i, prog->section_name); | |
1007 | goto out; | |
1008 | } | |
1009 | ||
1010 | if (!result.new_insn_ptr || !result.new_insn_cnt) { | |
1011 | pr_debug("Skip loading the %dth instance of program '%s'\n", | |
1012 | i, prog->section_name); | |
1013 | prog->instances.fds[i] = -1; | |
1014 | if (result.pfd) | |
1015 | *result.pfd = -1; | |
1016 | continue; | |
1017 | } | |
1018 | ||
5f44e4c8 | 1019 | err = load_program(prog->type, result.new_insn_ptr, |
b580563e WN |
1020 | result.new_insn_cnt, |
1021 | license, kern_version, &fd); | |
1022 | ||
1023 | if (err) { | |
1024 | pr_warning("Loading the %dth instance of program '%s' failed\n", | |
1025 | i, prog->section_name); | |
1026 | goto out; | |
1027 | } | |
1028 | ||
1029 | if (result.pfd) | |
1030 | *result.pfd = fd; | |
1031 | prog->instances.fds[i] = fd; | |
1032 | } | |
1033 | out: | |
55cffde2 WN |
1034 | if (err) |
1035 | pr_warning("failed to load program '%s'\n", | |
1036 | prog->section_name); | |
1037 | zfree(&prog->insns); | |
1038 | prog->insns_cnt = 0; | |
1039 | return err; | |
1040 | } | |
1041 | ||
1042 | static int | |
1043 | bpf_object__load_progs(struct bpf_object *obj) | |
1044 | { | |
1045 | size_t i; | |
1046 | int err; | |
1047 | ||
1048 | for (i = 0; i < obj->nr_programs; i++) { | |
1049 | err = bpf_program__load(&obj->programs[i], | |
1050 | obj->license, | |
1051 | obj->kern_version); | |
1052 | if (err) | |
1053 | return err; | |
1054 | } | |
1055 | return 0; | |
1056 | } | |
1057 | ||
cb1e5e96 WN |
1058 | static int bpf_object__validate(struct bpf_object *obj) |
1059 | { | |
1060 | if (obj->kern_version == 0) { | |
1061 | pr_warning("%s doesn't provide kernel version\n", | |
1062 | obj->path); | |
6371ca3b | 1063 | return -LIBBPF_ERRNO__KVERSION; |
cb1e5e96 WN |
1064 | } |
1065 | return 0; | |
1066 | } | |
1067 | ||
1a5e3fb1 | 1068 | static struct bpf_object * |
6c956392 | 1069 | __bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz) |
1a5e3fb1 WN |
1070 | { |
1071 | struct bpf_object *obj; | |
6371ca3b | 1072 | int err; |
1a5e3fb1 WN |
1073 | |
1074 | if (elf_version(EV_CURRENT) == EV_NONE) { | |
1075 | pr_warning("failed to init libelf for %s\n", path); | |
6371ca3b | 1076 | return ERR_PTR(-LIBBPF_ERRNO__LIBELF); |
1a5e3fb1 WN |
1077 | } |
1078 | ||
6c956392 | 1079 | obj = bpf_object__new(path, obj_buf, obj_buf_sz); |
6371ca3b WN |
1080 | if (IS_ERR(obj)) |
1081 | return obj; | |
1a5e3fb1 | 1082 | |
6371ca3b WN |
1083 | CHECK_ERR(bpf_object__elf_init(obj), err, out); |
1084 | CHECK_ERR(bpf_object__check_endianness(obj), err, out); | |
1085 | CHECK_ERR(bpf_object__elf_collect(obj), err, out); | |
1086 | CHECK_ERR(bpf_object__collect_reloc(obj), err, out); | |
1087 | CHECK_ERR(bpf_object__validate(obj), err, out); | |
1a5e3fb1 WN |
1088 | |
1089 | bpf_object__elf_finish(obj); | |
1090 | return obj; | |
1091 | out: | |
1092 | bpf_object__close(obj); | |
6371ca3b | 1093 | return ERR_PTR(err); |
1a5e3fb1 WN |
1094 | } |
1095 | ||
1096 | struct bpf_object *bpf_object__open(const char *path) | |
1097 | { | |
1098 | /* param validation */ | |
1099 | if (!path) | |
1100 | return NULL; | |
1101 | ||
1102 | pr_debug("loading %s\n", path); | |
1103 | ||
6c956392 WN |
1104 | return __bpf_object__open(path, NULL, 0); |
1105 | } | |
1106 | ||
1107 | struct bpf_object *bpf_object__open_buffer(void *obj_buf, | |
acf860ae WN |
1108 | size_t obj_buf_sz, |
1109 | const char *name) | |
6c956392 | 1110 | { |
acf860ae WN |
1111 | char tmp_name[64]; |
1112 | ||
6c956392 WN |
1113 | /* param validation */ |
1114 | if (!obj_buf || obj_buf_sz <= 0) | |
1115 | return NULL; | |
1116 | ||
acf860ae WN |
1117 | if (!name) { |
1118 | snprintf(tmp_name, sizeof(tmp_name), "%lx-%lx", | |
1119 | (unsigned long)obj_buf, | |
1120 | (unsigned long)obj_buf_sz); | |
1121 | tmp_name[sizeof(tmp_name) - 1] = '\0'; | |
1122 | name = tmp_name; | |
1123 | } | |
1124 | pr_debug("loading object '%s' from buffer\n", | |
1125 | name); | |
6c956392 | 1126 | |
acf860ae | 1127 | return __bpf_object__open(name, obj_buf, obj_buf_sz); |
1a5e3fb1 WN |
1128 | } |
1129 | ||
52d3352e WN |
1130 | int bpf_object__unload(struct bpf_object *obj) |
1131 | { | |
1132 | size_t i; | |
1133 | ||
1134 | if (!obj) | |
1135 | return -EINVAL; | |
1136 | ||
9d759a9b WN |
1137 | for (i = 0; i < obj->nr_maps; i++) |
1138 | zclose(obj->maps[i].fd); | |
52d3352e | 1139 | |
55cffde2 WN |
1140 | for (i = 0; i < obj->nr_programs; i++) |
1141 | bpf_program__unload(&obj->programs[i]); | |
1142 | ||
52d3352e WN |
1143 | return 0; |
1144 | } | |
1145 | ||
1146 | int bpf_object__load(struct bpf_object *obj) | |
1147 | { | |
6371ca3b WN |
1148 | int err; |
1149 | ||
52d3352e WN |
1150 | if (!obj) |
1151 | return -EINVAL; | |
1152 | ||
1153 | if (obj->loaded) { | |
1154 | pr_warning("object should not be loaded twice\n"); | |
1155 | return -EINVAL; | |
1156 | } | |
1157 | ||
1158 | obj->loaded = true; | |
6371ca3b WN |
1159 | |
1160 | CHECK_ERR(bpf_object__create_maps(obj), err, out); | |
1161 | CHECK_ERR(bpf_object__relocate(obj), err, out); | |
1162 | CHECK_ERR(bpf_object__load_progs(obj), err, out); | |
52d3352e WN |
1163 | |
1164 | return 0; | |
1165 | out: | |
1166 | bpf_object__unload(obj); | |
1167 | pr_warning("failed to load object '%s'\n", obj->path); | |
6371ca3b | 1168 | return err; |
52d3352e WN |
1169 | } |
1170 | ||
1a5e3fb1 WN |
1171 | void bpf_object__close(struct bpf_object *obj) |
1172 | { | |
a5b8bd47 WN |
1173 | size_t i; |
1174 | ||
1a5e3fb1 WN |
1175 | if (!obj) |
1176 | return; | |
1177 | ||
1178 | bpf_object__elf_finish(obj); | |
52d3352e | 1179 | bpf_object__unload(obj); |
1a5e3fb1 | 1180 | |
9d759a9b | 1181 | for (i = 0; i < obj->nr_maps; i++) { |
561bbcca | 1182 | zfree(&obj->maps[i].name); |
9d759a9b WN |
1183 | if (obj->maps[i].clear_priv) |
1184 | obj->maps[i].clear_priv(&obj->maps[i], | |
1185 | obj->maps[i].priv); | |
1186 | obj->maps[i].priv = NULL; | |
1187 | obj->maps[i].clear_priv = NULL; | |
1188 | } | |
1189 | zfree(&obj->maps); | |
1190 | obj->nr_maps = 0; | |
a5b8bd47 WN |
1191 | |
1192 | if (obj->programs && obj->nr_programs) { | |
1193 | for (i = 0; i < obj->nr_programs; i++) | |
1194 | bpf_program__exit(&obj->programs[i]); | |
1195 | } | |
1196 | zfree(&obj->programs); | |
1197 | ||
9a208eff | 1198 | list_del(&obj->list); |
1a5e3fb1 WN |
1199 | free(obj); |
1200 | } | |
aa9b1ac3 | 1201 | |
9a208eff WN |
1202 | struct bpf_object * |
1203 | bpf_object__next(struct bpf_object *prev) | |
1204 | { | |
1205 | struct bpf_object *next; | |
1206 | ||
1207 | if (!prev) | |
1208 | next = list_first_entry(&bpf_objects_list, | |
1209 | struct bpf_object, | |
1210 | list); | |
1211 | else | |
1212 | next = list_next_entry(prev, list); | |
1213 | ||
1214 | /* Empty list is noticed here so don't need checking on entry. */ | |
1215 | if (&next->list == &bpf_objects_list) | |
1216 | return NULL; | |
1217 | ||
1218 | return next; | |
1219 | } | |
1220 | ||
a7fe0450 | 1221 | const char *bpf_object__name(struct bpf_object *obj) |
acf860ae | 1222 | { |
a7fe0450 | 1223 | return obj ? obj->path : ERR_PTR(-EINVAL); |
acf860ae WN |
1224 | } |
1225 | ||
a7fe0450 | 1226 | unsigned int bpf_object__kversion(struct bpf_object *obj) |
45825d8a | 1227 | { |
a7fe0450 | 1228 | return obj ? obj->kern_version : 0; |
45825d8a WN |
1229 | } |
1230 | ||
aa9b1ac3 WN |
1231 | struct bpf_program * |
1232 | bpf_program__next(struct bpf_program *prev, struct bpf_object *obj) | |
1233 | { | |
1234 | size_t idx; | |
1235 | ||
1236 | if (!obj->programs) | |
1237 | return NULL; | |
1238 | /* First handler */ | |
1239 | if (prev == NULL) | |
1240 | return &obj->programs[0]; | |
1241 | ||
1242 | if (prev->obj != obj) { | |
1243 | pr_warning("error: program handler doesn't match object\n"); | |
1244 | return NULL; | |
1245 | } | |
1246 | ||
1247 | idx = (prev - obj->programs) + 1; | |
1248 | if (idx >= obj->nr_programs) | |
1249 | return NULL; | |
1250 | return &obj->programs[idx]; | |
1251 | } | |
1252 | ||
edb13ed4 ACM |
1253 | int bpf_program__set_priv(struct bpf_program *prog, void *priv, |
1254 | bpf_program_clear_priv_t clear_priv) | |
aa9b1ac3 WN |
1255 | { |
1256 | if (prog->priv && prog->clear_priv) | |
1257 | prog->clear_priv(prog, prog->priv); | |
1258 | ||
1259 | prog->priv = priv; | |
1260 | prog->clear_priv = clear_priv; | |
1261 | return 0; | |
1262 | } | |
1263 | ||
be834ffb | 1264 | void *bpf_program__priv(struct bpf_program *prog) |
aa9b1ac3 | 1265 | { |
be834ffb | 1266 | return prog ? prog->priv : ERR_PTR(-EINVAL); |
aa9b1ac3 WN |
1267 | } |
1268 | ||
715f8db9 | 1269 | const char *bpf_program__title(struct bpf_program *prog, bool needs_copy) |
aa9b1ac3 WN |
1270 | { |
1271 | const char *title; | |
1272 | ||
1273 | title = prog->section_name; | |
715f8db9 | 1274 | if (needs_copy) { |
aa9b1ac3 WN |
1275 | title = strdup(title); |
1276 | if (!title) { | |
1277 | pr_warning("failed to strdup program title\n"); | |
6371ca3b | 1278 | return ERR_PTR(-ENOMEM); |
aa9b1ac3 WN |
1279 | } |
1280 | } | |
1281 | ||
1282 | return title; | |
1283 | } | |
1284 | ||
1285 | int bpf_program__fd(struct bpf_program *prog) | |
1286 | { | |
b580563e WN |
1287 | return bpf_program__nth_fd(prog, 0); |
1288 | } | |
1289 | ||
1290 | int bpf_program__set_prep(struct bpf_program *prog, int nr_instances, | |
1291 | bpf_program_prep_t prep) | |
1292 | { | |
1293 | int *instances_fds; | |
1294 | ||
1295 | if (nr_instances <= 0 || !prep) | |
1296 | return -EINVAL; | |
1297 | ||
1298 | if (prog->instances.nr > 0 || prog->instances.fds) { | |
1299 | pr_warning("Can't set pre-processor after loading\n"); | |
1300 | return -EINVAL; | |
1301 | } | |
1302 | ||
1303 | instances_fds = malloc(sizeof(int) * nr_instances); | |
1304 | if (!instances_fds) { | |
1305 | pr_warning("alloc memory failed for fds\n"); | |
1306 | return -ENOMEM; | |
1307 | } | |
1308 | ||
1309 | /* fill all fd with -1 */ | |
1310 | memset(instances_fds, -1, sizeof(int) * nr_instances); | |
1311 | ||
1312 | prog->instances.nr = nr_instances; | |
1313 | prog->instances.fds = instances_fds; | |
1314 | prog->preprocessor = prep; | |
1315 | return 0; | |
1316 | } | |
1317 | ||
1318 | int bpf_program__nth_fd(struct bpf_program *prog, int n) | |
1319 | { | |
1320 | int fd; | |
1321 | ||
1322 | if (n >= prog->instances.nr || n < 0) { | |
1323 | pr_warning("Can't get the %dth fd from program %s: only %d instances\n", | |
1324 | n, prog->section_name, prog->instances.nr); | |
1325 | return -EINVAL; | |
1326 | } | |
1327 | ||
1328 | fd = prog->instances.fds[n]; | |
1329 | if (fd < 0) { | |
1330 | pr_warning("%dth instance of program '%s' is invalid\n", | |
1331 | n, prog->section_name); | |
1332 | return -ENOENT; | |
1333 | } | |
1334 | ||
1335 | return fd; | |
aa9b1ac3 | 1336 | } |
9d759a9b | 1337 | |
5f44e4c8 WN |
1338 | static void bpf_program__set_type(struct bpf_program *prog, |
1339 | enum bpf_prog_type type) | |
1340 | { | |
1341 | prog->type = type; | |
1342 | } | |
1343 | ||
1344 | int bpf_program__set_tracepoint(struct bpf_program *prog) | |
1345 | { | |
1346 | if (!prog) | |
1347 | return -EINVAL; | |
1348 | bpf_program__set_type(prog, BPF_PROG_TYPE_TRACEPOINT); | |
1349 | return 0; | |
1350 | } | |
1351 | ||
1352 | int bpf_program__set_kprobe(struct bpf_program *prog) | |
1353 | { | |
1354 | if (!prog) | |
1355 | return -EINVAL; | |
1356 | bpf_program__set_type(prog, BPF_PROG_TYPE_KPROBE); | |
1357 | return 0; | |
1358 | } | |
1359 | ||
1360 | static bool bpf_program__is_type(struct bpf_program *prog, | |
1361 | enum bpf_prog_type type) | |
1362 | { | |
1363 | return prog ? (prog->type == type) : false; | |
1364 | } | |
1365 | ||
1366 | bool bpf_program__is_tracepoint(struct bpf_program *prog) | |
1367 | { | |
1368 | return bpf_program__is_type(prog, BPF_PROG_TYPE_TRACEPOINT); | |
1369 | } | |
1370 | ||
1371 | bool bpf_program__is_kprobe(struct bpf_program *prog) | |
1372 | { | |
1373 | return bpf_program__is_type(prog, BPF_PROG_TYPE_KPROBE); | |
1374 | } | |
1375 | ||
6e009e65 | 1376 | int bpf_map__fd(struct bpf_map *map) |
9d759a9b | 1377 | { |
6e009e65 | 1378 | return map ? map->fd : -EINVAL; |
9d759a9b WN |
1379 | } |
1380 | ||
53897a78 | 1381 | const struct bpf_map_def *bpf_map__def(struct bpf_map *map) |
9d759a9b | 1382 | { |
53897a78 | 1383 | return map ? &map->def : ERR_PTR(-EINVAL); |
9d759a9b WN |
1384 | } |
1385 | ||
009ad5d5 | 1386 | const char *bpf_map__name(struct bpf_map *map) |
561bbcca | 1387 | { |
009ad5d5 | 1388 | return map ? map->name : NULL; |
561bbcca WN |
1389 | } |
1390 | ||
edb13ed4 ACM |
1391 | int bpf_map__set_priv(struct bpf_map *map, void *priv, |
1392 | bpf_map_clear_priv_t clear_priv) | |
9d759a9b WN |
1393 | { |
1394 | if (!map) | |
1395 | return -EINVAL; | |
1396 | ||
1397 | if (map->priv) { | |
1398 | if (map->clear_priv) | |
1399 | map->clear_priv(map, map->priv); | |
1400 | } | |
1401 | ||
1402 | map->priv = priv; | |
1403 | map->clear_priv = clear_priv; | |
1404 | return 0; | |
1405 | } | |
1406 | ||
b4cbfa56 | 1407 | void *bpf_map__priv(struct bpf_map *map) |
9d759a9b | 1408 | { |
b4cbfa56 | 1409 | return map ? map->priv : ERR_PTR(-EINVAL); |
9d759a9b WN |
1410 | } |
1411 | ||
1412 | struct bpf_map * | |
1413 | bpf_map__next(struct bpf_map *prev, struct bpf_object *obj) | |
1414 | { | |
1415 | size_t idx; | |
1416 | struct bpf_map *s, *e; | |
1417 | ||
1418 | if (!obj || !obj->maps) | |
1419 | return NULL; | |
1420 | ||
1421 | s = obj->maps; | |
1422 | e = obj->maps + obj->nr_maps; | |
1423 | ||
1424 | if (prev == NULL) | |
1425 | return s; | |
1426 | ||
1427 | if ((prev < s) || (prev >= e)) { | |
1428 | pr_warning("error in %s: map handler doesn't belong to object\n", | |
1429 | __func__); | |
1430 | return NULL; | |
1431 | } | |
1432 | ||
1433 | idx = (prev - obj->maps) + 1; | |
1434 | if (idx >= obj->nr_maps) | |
1435 | return NULL; | |
1436 | return &obj->maps[idx]; | |
1437 | } | |
561bbcca WN |
1438 | |
1439 | struct bpf_map * | |
a7fe0450 | 1440 | bpf_object__find_map_by_name(struct bpf_object *obj, const char *name) |
561bbcca WN |
1441 | { |
1442 | struct bpf_map *pos; | |
1443 | ||
1444 | bpf_map__for_each(pos, obj) { | |
973170e6 | 1445 | if (pos->name && !strcmp(pos->name, name)) |
561bbcca WN |
1446 | return pos; |
1447 | } | |
1448 | return NULL; | |
1449 | } |