mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-04 09:59:32 +00:00
![Alexei Starovoitov](/assets/img/avatar_default.png)
expose bpf_program__set_type() to set program type Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1746 lines
38 KiB
C
1746 lines
38 KiB
C
/*
|
|
* Common eBPF ELF object loading operations.
|
|
*
|
|
* Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
|
|
* Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
|
|
* Copyright (C) 2015 Huawei Inc.
|
|
* Copyright (C) 2017 Nicira, Inc.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation;
|
|
* version 2.1 of the License (not later!)
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this program; if not, see <http://www.gnu.org/licenses>
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
#include <stdarg.h>
|
|
#include <libgen.h>
|
|
#include <inttypes.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <fcntl.h>
|
|
#include <errno.h>
|
|
#include <asm/unistd.h>
|
|
#include <linux/err.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/bpf.h>
|
|
#include <linux/list.h>
|
|
#include <linux/limits.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/types.h>
|
|
#include <sys/vfs.h>
|
|
#include <libelf.h>
|
|
#include <gelf.h>
|
|
|
|
#include "libbpf.h"
|
|
#include "bpf.h"
|
|
|
|
#ifndef EM_BPF
|
|
#define EM_BPF 247
|
|
#endif
|
|
|
|
#ifndef BPF_FS_MAGIC
|
|
#define BPF_FS_MAGIC 0xcafe4a11
|
|
#endif
|
|
|
|
#define __printf(a, b) __attribute__((format(printf, a, b)))
|
|
|
|
__printf(1, 2)
|
|
static int __base_pr(const char *format, ...)
|
|
{
|
|
va_list args;
|
|
int err;
|
|
|
|
va_start(args, format);
|
|
err = vfprintf(stderr, format, args);
|
|
va_end(args);
|
|
return err;
|
|
}
|
|
|
|
static __printf(1, 2) libbpf_print_fn_t __pr_warning = __base_pr;
|
|
static __printf(1, 2) libbpf_print_fn_t __pr_info = __base_pr;
|
|
static __printf(1, 2) libbpf_print_fn_t __pr_debug;
|
|
|
|
#define __pr(func, fmt, ...) \
|
|
do { \
|
|
if ((func)) \
|
|
(func)("libbpf: " fmt, ##__VA_ARGS__); \
|
|
} while (0)
|
|
|
|
#define pr_warning(fmt, ...) __pr(__pr_warning, fmt, ##__VA_ARGS__)
|
|
#define pr_info(fmt, ...) __pr(__pr_info, fmt, ##__VA_ARGS__)
|
|
#define pr_debug(fmt, ...) __pr(__pr_debug, fmt, ##__VA_ARGS__)
|
|
|
|
void libbpf_set_print(libbpf_print_fn_t warn,
|
|
libbpf_print_fn_t info,
|
|
libbpf_print_fn_t debug)
|
|
{
|
|
__pr_warning = warn;
|
|
__pr_info = info;
|
|
__pr_debug = debug;
|
|
}
|
|
|
|
#define STRERR_BUFSIZE 128
|
|
|
|
#define ERRNO_OFFSET(e) ((e) - __LIBBPF_ERRNO__START)
|
|
#define ERRCODE_OFFSET(c) ERRNO_OFFSET(LIBBPF_ERRNO__##c)
|
|
#define NR_ERRNO (__LIBBPF_ERRNO__END - __LIBBPF_ERRNO__START)
|
|
|
|
static const char *libbpf_strerror_table[NR_ERRNO] = {
|
|
[ERRCODE_OFFSET(LIBELF)] = "Something wrong in libelf",
|
|
[ERRCODE_OFFSET(FORMAT)] = "BPF object format invalid",
|
|
[ERRCODE_OFFSET(KVERSION)] = "'version' section incorrect or lost",
|
|
[ERRCODE_OFFSET(ENDIAN)] = "Endian mismatch",
|
|
[ERRCODE_OFFSET(INTERNAL)] = "Internal error in libbpf",
|
|
[ERRCODE_OFFSET(RELOC)] = "Relocation failed",
|
|
[ERRCODE_OFFSET(VERIFY)] = "Kernel verifier blocks program loading",
|
|
[ERRCODE_OFFSET(PROG2BIG)] = "Program too big",
|
|
[ERRCODE_OFFSET(KVER)] = "Incorrect kernel version",
|
|
[ERRCODE_OFFSET(PROGTYPE)] = "Kernel doesn't support this program type",
|
|
};
|
|
|
|
int libbpf_strerror(int err, char *buf, size_t size)
|
|
{
|
|
if (!buf || !size)
|
|
return -1;
|
|
|
|
err = err > 0 ? err : -err;
|
|
|
|
if (err < __LIBBPF_ERRNO__START) {
|
|
int ret;
|
|
|
|
ret = strerror_r(err, buf, size);
|
|
buf[size - 1] = '\0';
|
|
return ret;
|
|
}
|
|
|
|
if (err < __LIBBPF_ERRNO__END) {
|
|
const char *msg;
|
|
|
|
msg = libbpf_strerror_table[ERRNO_OFFSET(err)];
|
|
snprintf(buf, size, "%s", msg);
|
|
buf[size - 1] = '\0';
|
|
return 0;
|
|
}
|
|
|
|
snprintf(buf, size, "Unknown libbpf error %d", err);
|
|
buf[size - 1] = '\0';
|
|
return -1;
|
|
}
|
|
|
|
#define CHECK_ERR(action, err, out) do { \
|
|
err = action; \
|
|
if (err) \
|
|
goto out; \
|
|
} while(0)
|
|
|
|
|
|
/* Copied from tools/perf/util/util.h */
|
|
#ifndef zfree
|
|
# define zfree(ptr) ({ free(*ptr); *ptr = NULL; })
|
|
#endif
|
|
|
|
#ifndef zclose
|
|
# define zclose(fd) ({ \
|
|
int ___err = 0; \
|
|
if ((fd) >= 0) \
|
|
___err = close((fd)); \
|
|
fd = -1; \
|
|
___err; })
|
|
#endif
|
|
|
|
#ifdef HAVE_LIBELF_MMAP_SUPPORT
|
|
# define LIBBPF_ELF_C_READ_MMAP ELF_C_READ_MMAP
|
|
#else
|
|
# define LIBBPF_ELF_C_READ_MMAP ELF_C_READ
|
|
#endif
|
|
|
|
/*
|
|
* bpf_prog should be a better name but it has been used in
|
|
* linux/filter.h.
|
|
*/
|
|
struct bpf_program {
|
|
/* Index in elf obj file, for relocation use. */
|
|
int idx;
|
|
char *section_name;
|
|
struct bpf_insn *insns;
|
|
size_t insns_cnt;
|
|
enum bpf_prog_type type;
|
|
|
|
struct {
|
|
int insn_idx;
|
|
int map_idx;
|
|
} *reloc_desc;
|
|
int nr_reloc;
|
|
|
|
struct {
|
|
int nr;
|
|
int *fds;
|
|
} instances;
|
|
bpf_program_prep_t preprocessor;
|
|
|
|
struct bpf_object *obj;
|
|
void *priv;
|
|
bpf_program_clear_priv_t clear_priv;
|
|
};
|
|
|
|
struct bpf_map {
|
|
int fd;
|
|
char *name;
|
|
size_t offset;
|
|
struct bpf_map_def def;
|
|
void *priv;
|
|
bpf_map_clear_priv_t clear_priv;
|
|
};
|
|
|
|
static LIST_HEAD(bpf_objects_list);
|
|
|
|
struct bpf_object {
|
|
char license[64];
|
|
u32 kern_version;
|
|
|
|
struct bpf_program *programs;
|
|
size_t nr_programs;
|
|
struct bpf_map *maps;
|
|
size_t nr_maps;
|
|
|
|
bool loaded;
|
|
|
|
/*
|
|
* Information when doing elf related work. Only valid if fd
|
|
* is valid.
|
|
*/
|
|
struct {
|
|
int fd;
|
|
void *obj_buf;
|
|
size_t obj_buf_sz;
|
|
Elf *elf;
|
|
GElf_Ehdr ehdr;
|
|
Elf_Data *symbols;
|
|
size_t strtabidx;
|
|
struct {
|
|
GElf_Shdr shdr;
|
|
Elf_Data *data;
|
|
} *reloc;
|
|
int nr_reloc;
|
|
int maps_shndx;
|
|
} efile;
|
|
/*
|
|
* All loaded bpf_object is linked in a list, which is
|
|
* hidden to caller. bpf_objects__<func> handlers deal with
|
|
* all objects.
|
|
*/
|
|
struct list_head list;
|
|
|
|
void *priv;
|
|
bpf_object_clear_priv_t clear_priv;
|
|
|
|
char path[];
|
|
};
|
|
#define obj_elf_valid(o) ((o)->efile.elf)
|
|
|
|
static void bpf_program__unload(struct bpf_program *prog)
|
|
{
|
|
int i;
|
|
|
|
if (!prog)
|
|
return;
|
|
|
|
/*
|
|
* If the object is opened but the program was never loaded,
|
|
* it is possible that prog->instances.nr == -1.
|
|
*/
|
|
if (prog->instances.nr > 0) {
|
|
for (i = 0; i < prog->instances.nr; i++)
|
|
zclose(prog->instances.fds[i]);
|
|
} else if (prog->instances.nr != -1) {
|
|
pr_warning("Internal error: instances.nr is %d\n",
|
|
prog->instances.nr);
|
|
}
|
|
|
|
prog->instances.nr = -1;
|
|
zfree(&prog->instances.fds);
|
|
}
|
|
|
|
static void bpf_program__exit(struct bpf_program *prog)
|
|
{
|
|
if (!prog)
|
|
return;
|
|
|
|
if (prog->clear_priv)
|
|
prog->clear_priv(prog, prog->priv);
|
|
|
|
prog->priv = NULL;
|
|
prog->clear_priv = NULL;
|
|
|
|
bpf_program__unload(prog);
|
|
zfree(&prog->section_name);
|
|
zfree(&prog->insns);
|
|
zfree(&prog->reloc_desc);
|
|
|
|
prog->nr_reloc = 0;
|
|
prog->insns_cnt = 0;
|
|
prog->idx = -1;
|
|
}
|
|
|
|
static int
|
|
bpf_program__init(void *data, size_t size, char *name, int idx,
|
|
struct bpf_program *prog)
|
|
{
|
|
if (size < sizeof(struct bpf_insn)) {
|
|
pr_warning("corrupted section '%s'\n", name);
|
|
return -EINVAL;
|
|
}
|
|
|
|
bzero(prog, sizeof(*prog));
|
|
|
|
prog->section_name = strdup(name);
|
|
if (!prog->section_name) {
|
|
pr_warning("failed to alloc name for prog %s\n",
|
|
name);
|
|
goto errout;
|
|
}
|
|
|
|
prog->insns = malloc(size);
|
|
if (!prog->insns) {
|
|
pr_warning("failed to alloc insns for %s\n", name);
|
|
goto errout;
|
|
}
|
|
prog->insns_cnt = size / sizeof(struct bpf_insn);
|
|
memcpy(prog->insns, data,
|
|
prog->insns_cnt * sizeof(struct bpf_insn));
|
|
prog->idx = idx;
|
|
prog->instances.fds = NULL;
|
|
prog->instances.nr = -1;
|
|
prog->type = BPF_PROG_TYPE_KPROBE;
|
|
|
|
return 0;
|
|
errout:
|
|
bpf_program__exit(prog);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static int
|
|
bpf_object__add_program(struct bpf_object *obj, void *data, size_t size,
|
|
char *name, int idx)
|
|
{
|
|
struct bpf_program prog, *progs;
|
|
int nr_progs, err;
|
|
|
|
err = bpf_program__init(data, size, name, idx, &prog);
|
|
if (err)
|
|
return err;
|
|
|
|
progs = obj->programs;
|
|
nr_progs = obj->nr_programs;
|
|
|
|
progs = realloc(progs, sizeof(progs[0]) * (nr_progs + 1));
|
|
if (!progs) {
|
|
/*
|
|
* In this case the original obj->programs
|
|
* is still valid, so don't need special treat for
|
|
* bpf_close_object().
|
|
*/
|
|
pr_warning("failed to alloc a new program '%s'\n",
|
|
name);
|
|
bpf_program__exit(&prog);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
pr_debug("found program %s\n", prog.section_name);
|
|
obj->programs = progs;
|
|
obj->nr_programs = nr_progs + 1;
|
|
prog.obj = obj;
|
|
progs[nr_progs] = prog;
|
|
return 0;
|
|
}
|
|
|
|
static struct bpf_object *bpf_object__new(const char *path,
|
|
void *obj_buf,
|
|
size_t obj_buf_sz)
|
|
{
|
|
struct bpf_object *obj;
|
|
|
|
obj = calloc(1, sizeof(struct bpf_object) + strlen(path) + 1);
|
|
if (!obj) {
|
|
pr_warning("alloc memory failed for %s\n", path);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
strcpy(obj->path, path);
|
|
obj->efile.fd = -1;
|
|
|
|
/*
|
|
* Caller of this function should also calls
|
|
* bpf_object__elf_finish() after data collection to return
|
|
* obj_buf to user. If not, we should duplicate the buffer to
|
|
* avoid user freeing them before elf finish.
|
|
*/
|
|
obj->efile.obj_buf = obj_buf;
|
|
obj->efile.obj_buf_sz = obj_buf_sz;
|
|
obj->efile.maps_shndx = -1;
|
|
|
|
obj->loaded = false;
|
|
|
|
INIT_LIST_HEAD(&obj->list);
|
|
list_add(&obj->list, &bpf_objects_list);
|
|
return obj;
|
|
}
|
|
|
|
static void bpf_object__elf_finish(struct bpf_object *obj)
|
|
{
|
|
if (!obj_elf_valid(obj))
|
|
return;
|
|
|
|
if (obj->efile.elf) {
|
|
elf_end(obj->efile.elf);
|
|
obj->efile.elf = NULL;
|
|
}
|
|
obj->efile.symbols = NULL;
|
|
|
|
zfree(&obj->efile.reloc);
|
|
obj->efile.nr_reloc = 0;
|
|
zclose(obj->efile.fd);
|
|
obj->efile.obj_buf = NULL;
|
|
obj->efile.obj_buf_sz = 0;
|
|
}
|
|
|
|
static int bpf_object__elf_init(struct bpf_object *obj)
|
|
{
|
|
int err = 0;
|
|
GElf_Ehdr *ep;
|
|
|
|
if (obj_elf_valid(obj)) {
|
|
pr_warning("elf init: internal error\n");
|
|
return -LIBBPF_ERRNO__LIBELF;
|
|
}
|
|
|
|
if (obj->efile.obj_buf_sz > 0) {
|
|
/*
|
|
* obj_buf should have been validated by
|
|
* bpf_object__open_buffer().
|
|
*/
|
|
obj->efile.elf = elf_memory(obj->efile.obj_buf,
|
|
obj->efile.obj_buf_sz);
|
|
} else {
|
|
obj->efile.fd = open(obj->path, O_RDONLY);
|
|
if (obj->efile.fd < 0) {
|
|
pr_warning("failed to open %s: %s\n", obj->path,
|
|
strerror(errno));
|
|
return -errno;
|
|
}
|
|
|
|
obj->efile.elf = elf_begin(obj->efile.fd,
|
|
LIBBPF_ELF_C_READ_MMAP,
|
|
NULL);
|
|
}
|
|
|
|
if (!obj->efile.elf) {
|
|
pr_warning("failed to open %s as ELF file\n",
|
|
obj->path);
|
|
err = -LIBBPF_ERRNO__LIBELF;
|
|
goto errout;
|
|
}
|
|
|
|
if (!gelf_getehdr(obj->efile.elf, &obj->efile.ehdr)) {
|
|
pr_warning("failed to get EHDR from %s\n",
|
|
obj->path);
|
|
err = -LIBBPF_ERRNO__FORMAT;
|
|
goto errout;
|
|
}
|
|
ep = &obj->efile.ehdr;
|
|
|
|
/* Old LLVM set e_machine to EM_NONE */
|
|
if ((ep->e_type != ET_REL) || (ep->e_machine && (ep->e_machine != EM_BPF))) {
|
|
pr_warning("%s is not an eBPF object file\n",
|
|
obj->path);
|
|
err = -LIBBPF_ERRNO__FORMAT;
|
|
goto errout;
|
|
}
|
|
|
|
return 0;
|
|
errout:
|
|
bpf_object__elf_finish(obj);
|
|
return err;
|
|
}
|
|
|
|
static int
|
|
bpf_object__check_endianness(struct bpf_object *obj)
|
|
{
|
|
static unsigned int const endian = 1;
|
|
|
|
switch (obj->efile.ehdr.e_ident[EI_DATA]) {
|
|
case ELFDATA2LSB:
|
|
/* We are big endian, BPF obj is little endian. */
|
|
if (*(unsigned char const *)&endian != 1)
|
|
goto mismatch;
|
|
break;
|
|
|
|
case ELFDATA2MSB:
|
|
/* We are little endian, BPF obj is big endian. */
|
|
if (*(unsigned char const *)&endian != 0)
|
|
goto mismatch;
|
|
break;
|
|
default:
|
|
return -LIBBPF_ERRNO__ENDIAN;
|
|
}
|
|
|
|
return 0;
|
|
|
|
mismatch:
|
|
pr_warning("Error: endianness mismatch.\n");
|
|
return -LIBBPF_ERRNO__ENDIAN;
|
|
}
|
|
|
|
static int
|
|
bpf_object__init_license(struct bpf_object *obj,
|
|
void *data, size_t size)
|
|
{
|
|
memcpy(obj->license, data,
|
|
min(size, sizeof(obj->license) - 1));
|
|
pr_debug("license of %s is %s\n", obj->path, obj->license);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
bpf_object__init_kversion(struct bpf_object *obj,
|
|
void *data, size_t size)
|
|
{
|
|
u32 kver;
|
|
|
|
if (size != sizeof(kver)) {
|
|
pr_warning("invalid kver section in %s\n", obj->path);
|
|
return -LIBBPF_ERRNO__FORMAT;
|
|
}
|
|
memcpy(&kver, data, sizeof(kver));
|
|
obj->kern_version = kver;
|
|
pr_debug("kernel version of %s is %x\n", obj->path,
|
|
obj->kern_version);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
bpf_object__validate_maps(struct bpf_object *obj)
|
|
{
|
|
int i;
|
|
|
|
/*
|
|
* If there's only 1 map, the only error case should have been
|
|
* catched in bpf_object__init_maps().
|
|
*/
|
|
if (!obj->maps || !obj->nr_maps || (obj->nr_maps == 1))
|
|
return 0;
|
|
|
|
for (i = 1; i < obj->nr_maps; i++) {
|
|
const struct bpf_map *a = &obj->maps[i - 1];
|
|
const struct bpf_map *b = &obj->maps[i];
|
|
|
|
if (b->offset - a->offset < sizeof(struct bpf_map_def)) {
|
|
pr_warning("corrupted map section in %s: map \"%s\" too small\n",
|
|
obj->path, a->name);
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int compare_bpf_map(const void *_a, const void *_b)
|
|
{
|
|
const struct bpf_map *a = _a;
|
|
const struct bpf_map *b = _b;
|
|
|
|
return a->offset - b->offset;
|
|
}
|
|
|
|
static int
|
|
bpf_object__init_maps(struct bpf_object *obj)
|
|
{
|
|
int i, map_idx, nr_maps = 0;
|
|
Elf_Scn *scn;
|
|
Elf_Data *data;
|
|
Elf_Data *symbols = obj->efile.symbols;
|
|
|
|
if (obj->efile.maps_shndx < 0)
|
|
return -EINVAL;
|
|
if (!symbols)
|
|
return -EINVAL;
|
|
|
|
scn = elf_getscn(obj->efile.elf, obj->efile.maps_shndx);
|
|
if (scn)
|
|
data = elf_getdata(scn, NULL);
|
|
if (!scn || !data) {
|
|
pr_warning("failed to get Elf_Data from map section %d\n",
|
|
obj->efile.maps_shndx);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* Count number of maps. Each map has a name.
|
|
* Array of maps is not supported: only the first element is
|
|
* considered.
|
|
*
|
|
* TODO: Detect array of map and report error.
|
|
*/
|
|
for (i = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) {
|
|
GElf_Sym sym;
|
|
|
|
if (!gelf_getsym(symbols, i, &sym))
|
|
continue;
|
|
if (sym.st_shndx != obj->efile.maps_shndx)
|
|
continue;
|
|
nr_maps++;
|
|
}
|
|
|
|
/* Alloc obj->maps and fill nr_maps. */
|
|
pr_debug("maps in %s: %d maps in %zd bytes\n", obj->path,
|
|
nr_maps, data->d_size);
|
|
|
|
if (!nr_maps)
|
|
return 0;
|
|
|
|
obj->maps = calloc(nr_maps, sizeof(obj->maps[0]));
|
|
if (!obj->maps) {
|
|
pr_warning("alloc maps for object failed\n");
|
|
return -ENOMEM;
|
|
}
|
|
obj->nr_maps = nr_maps;
|
|
|
|
/*
|
|
* fill all fd with -1 so won't close incorrect
|
|
* fd (fd=0 is stdin) when failure (zclose won't close
|
|
* negative fd)).
|
|
*/
|
|
for (i = 0; i < nr_maps; i++)
|
|
obj->maps[i].fd = -1;
|
|
|
|
/*
|
|
* Fill obj->maps using data in "maps" section.
|
|
*/
|
|
for (i = 0, map_idx = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) {
|
|
GElf_Sym sym;
|
|
const char *map_name;
|
|
struct bpf_map_def *def;
|
|
|
|
if (!gelf_getsym(symbols, i, &sym))
|
|
continue;
|
|
if (sym.st_shndx != obj->efile.maps_shndx)
|
|
continue;
|
|
|
|
map_name = elf_strptr(obj->efile.elf,
|
|
obj->efile.strtabidx,
|
|
sym.st_name);
|
|
obj->maps[map_idx].offset = sym.st_value;
|
|
if (sym.st_value + sizeof(struct bpf_map_def) > data->d_size) {
|
|
pr_warning("corrupted maps section in %s: last map \"%s\" too small\n",
|
|
obj->path, map_name);
|
|
return -EINVAL;
|
|
}
|
|
|
|
obj->maps[map_idx].name = strdup(map_name);
|
|
if (!obj->maps[map_idx].name) {
|
|
pr_warning("failed to alloc map name\n");
|
|
return -ENOMEM;
|
|
}
|
|
pr_debug("map %d is \"%s\"\n", map_idx,
|
|
obj->maps[map_idx].name);
|
|
def = (struct bpf_map_def *)(data->d_buf + sym.st_value);
|
|
obj->maps[map_idx].def = *def;
|
|
map_idx++;
|
|
}
|
|
|
|
qsort(obj->maps, obj->nr_maps, sizeof(obj->maps[0]), compare_bpf_map);
|
|
return bpf_object__validate_maps(obj);
|
|
}
|
|
|
|
static int bpf_object__elf_collect(struct bpf_object *obj)
|
|
{
|
|
Elf *elf = obj->efile.elf;
|
|
GElf_Ehdr *ep = &obj->efile.ehdr;
|
|
Elf_Scn *scn = NULL;
|
|
int idx = 0, err = 0;
|
|
|
|
/* Elf is corrupted/truncated, avoid calling elf_strptr. */
|
|
if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) {
|
|
pr_warning("failed to get e_shstrndx from %s\n",
|
|
obj->path);
|
|
return -LIBBPF_ERRNO__FORMAT;
|
|
}
|
|
|
|
while ((scn = elf_nextscn(elf, scn)) != NULL) {
|
|
char *name;
|
|
GElf_Shdr sh;
|
|
Elf_Data *data;
|
|
|
|
idx++;
|
|
if (gelf_getshdr(scn, &sh) != &sh) {
|
|
pr_warning("failed to get section header from %s\n",
|
|
obj->path);
|
|
err = -LIBBPF_ERRNO__FORMAT;
|
|
goto out;
|
|
}
|
|
|
|
name = elf_strptr(elf, ep->e_shstrndx, sh.sh_name);
|
|
if (!name) {
|
|
pr_warning("failed to get section name from %s\n",
|
|
obj->path);
|
|
err = -LIBBPF_ERRNO__FORMAT;
|
|
goto out;
|
|
}
|
|
|
|
data = elf_getdata(scn, 0);
|
|
if (!data) {
|
|
pr_warning("failed to get section data from %s(%s)\n",
|
|
name, obj->path);
|
|
err = -LIBBPF_ERRNO__FORMAT;
|
|
goto out;
|
|
}
|
|
pr_debug("section %s, size %ld, link %d, flags %lx, type=%d\n",
|
|
name, (unsigned long)data->d_size,
|
|
(int)sh.sh_link, (unsigned long)sh.sh_flags,
|
|
(int)sh.sh_type);
|
|
|
|
if (strcmp(name, "license") == 0)
|
|
err = bpf_object__init_license(obj,
|
|
data->d_buf,
|
|
data->d_size);
|
|
else if (strcmp(name, "version") == 0)
|
|
err = bpf_object__init_kversion(obj,
|
|
data->d_buf,
|
|
data->d_size);
|
|
else if (strcmp(name, "maps") == 0)
|
|
obj->efile.maps_shndx = idx;
|
|
else if (sh.sh_type == SHT_SYMTAB) {
|
|
if (obj->efile.symbols) {
|
|
pr_warning("bpf: multiple SYMTAB in %s\n",
|
|
obj->path);
|
|
err = -LIBBPF_ERRNO__FORMAT;
|
|
} else {
|
|
obj->efile.symbols = data;
|
|
obj->efile.strtabidx = sh.sh_link;
|
|
}
|
|
} else if ((sh.sh_type == SHT_PROGBITS) &&
|
|
(sh.sh_flags & SHF_EXECINSTR) &&
|
|
(data->d_size > 0)) {
|
|
err = bpf_object__add_program(obj, data->d_buf,
|
|
data->d_size, name, idx);
|
|
if (err) {
|
|
char errmsg[STRERR_BUFSIZE];
|
|
|
|
strerror_r(-err, errmsg, sizeof(errmsg));
|
|
pr_warning("failed to alloc program %s (%s): %s",
|
|
name, obj->path, errmsg);
|
|
}
|
|
} else if (sh.sh_type == SHT_REL) {
|
|
void *reloc = obj->efile.reloc;
|
|
int nr_reloc = obj->efile.nr_reloc + 1;
|
|
|
|
reloc = realloc(reloc,
|
|
sizeof(*obj->efile.reloc) * nr_reloc);
|
|
if (!reloc) {
|
|
pr_warning("realloc failed\n");
|
|
err = -ENOMEM;
|
|
} else {
|
|
int n = nr_reloc - 1;
|
|
|
|
obj->efile.reloc = reloc;
|
|
obj->efile.nr_reloc = nr_reloc;
|
|
|
|
obj->efile.reloc[n].shdr = sh;
|
|
obj->efile.reloc[n].data = data;
|
|
}
|
|
}
|
|
if (err)
|
|
goto out;
|
|
}
|
|
|
|
if (!obj->efile.strtabidx || obj->efile.strtabidx >= idx) {
|
|
pr_warning("Corrupted ELF file: index of strtab invalid\n");
|
|
return LIBBPF_ERRNO__FORMAT;
|
|
}
|
|
if (obj->efile.maps_shndx >= 0)
|
|
err = bpf_object__init_maps(obj);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static struct bpf_program *
|
|
bpf_object__find_prog_by_idx(struct bpf_object *obj, int idx)
|
|
{
|
|
struct bpf_program *prog;
|
|
size_t i;
|
|
|
|
for (i = 0; i < obj->nr_programs; i++) {
|
|
prog = &obj->programs[i];
|
|
if (prog->idx == idx)
|
|
return prog;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static int
|
|
bpf_program__collect_reloc(struct bpf_program *prog,
|
|
size_t nr_maps, GElf_Shdr *shdr,
|
|
Elf_Data *data, Elf_Data *symbols,
|
|
int maps_shndx, struct bpf_map *maps)
|
|
{
|
|
int i, nrels;
|
|
|
|
pr_debug("collecting relocating info for: '%s'\n",
|
|
prog->section_name);
|
|
nrels = shdr->sh_size / shdr->sh_entsize;
|
|
|
|
prog->reloc_desc = malloc(sizeof(*prog->reloc_desc) * nrels);
|
|
if (!prog->reloc_desc) {
|
|
pr_warning("failed to alloc memory in relocation\n");
|
|
return -ENOMEM;
|
|
}
|
|
prog->nr_reloc = nrels;
|
|
|
|
for (i = 0; i < nrels; i++) {
|
|
GElf_Sym sym;
|
|
GElf_Rel rel;
|
|
unsigned int insn_idx;
|
|
struct bpf_insn *insns = prog->insns;
|
|
size_t map_idx;
|
|
|
|
if (!gelf_getrel(data, i, &rel)) {
|
|
pr_warning("relocation: failed to get %d reloc\n", i);
|
|
return -LIBBPF_ERRNO__FORMAT;
|
|
}
|
|
|
|
if (!gelf_getsym(symbols,
|
|
GELF_R_SYM(rel.r_info),
|
|
&sym)) {
|
|
pr_warning("relocation: symbol %"PRIx64" not found\n",
|
|
GELF_R_SYM(rel.r_info));
|
|
return -LIBBPF_ERRNO__FORMAT;
|
|
}
|
|
|
|
if (sym.st_shndx != maps_shndx) {
|
|
pr_warning("Program '%s' contains non-map related relo data pointing to section %u\n",
|
|
prog->section_name, sym.st_shndx);
|
|
return -LIBBPF_ERRNO__RELOC;
|
|
}
|
|
|
|
insn_idx = rel.r_offset / sizeof(struct bpf_insn);
|
|
pr_debug("relocation: insn_idx=%u\n", insn_idx);
|
|
|
|
if (insns[insn_idx].code != (BPF_LD | BPF_IMM | BPF_DW)) {
|
|
pr_warning("bpf: relocation: invalid relo for insns[%d].code 0x%x\n",
|
|
insn_idx, insns[insn_idx].code);
|
|
return -LIBBPF_ERRNO__RELOC;
|
|
}
|
|
|
|
/* TODO: 'maps' is sorted. We can use bsearch to make it faster. */
|
|
for (map_idx = 0; map_idx < nr_maps; map_idx++) {
|
|
if (maps[map_idx].offset == sym.st_value) {
|
|
pr_debug("relocation: find map %zd (%s) for insn %u\n",
|
|
map_idx, maps[map_idx].name, insn_idx);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (map_idx >= nr_maps) {
|
|
pr_warning("bpf relocation: map_idx %d large than %d\n",
|
|
(int)map_idx, (int)nr_maps - 1);
|
|
return -LIBBPF_ERRNO__RELOC;
|
|
}
|
|
|
|
prog->reloc_desc[i].insn_idx = insn_idx;
|
|
prog->reloc_desc[i].map_idx = map_idx;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
bpf_object__create_maps(struct bpf_object *obj)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < obj->nr_maps; i++) {
|
|
struct bpf_map_def *def = &obj->maps[i].def;
|
|
int *pfd = &obj->maps[i].fd;
|
|
|
|
*pfd = bpf_create_map(def->type,
|
|
def->key_size,
|
|
def->value_size,
|
|
def->max_entries,
|
|
0);
|
|
if (*pfd < 0) {
|
|
size_t j;
|
|
int err = *pfd;
|
|
|
|
pr_warning("failed to create map: %s\n",
|
|
strerror(errno));
|
|
for (j = 0; j < i; j++)
|
|
zclose(obj->maps[j].fd);
|
|
return err;
|
|
}
|
|
pr_debug("create map %s: fd=%d\n", obj->maps[i].name, *pfd);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
bpf_program__relocate(struct bpf_program *prog, struct bpf_object *obj)
|
|
{
|
|
int i;
|
|
|
|
if (!prog || !prog->reloc_desc)
|
|
return 0;
|
|
|
|
for (i = 0; i < prog->nr_reloc; i++) {
|
|
int insn_idx, map_idx;
|
|
struct bpf_insn *insns = prog->insns;
|
|
|
|
insn_idx = prog->reloc_desc[i].insn_idx;
|
|
map_idx = prog->reloc_desc[i].map_idx;
|
|
|
|
if (insn_idx >= (int)prog->insns_cnt) {
|
|
pr_warning("relocation out of range: '%s'\n",
|
|
prog->section_name);
|
|
return -LIBBPF_ERRNO__RELOC;
|
|
}
|
|
insns[insn_idx].src_reg = BPF_PSEUDO_MAP_FD;
|
|
insns[insn_idx].imm = obj->maps[map_idx].fd;
|
|
}
|
|
|
|
zfree(&prog->reloc_desc);
|
|
prog->nr_reloc = 0;
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int
|
|
bpf_object__relocate(struct bpf_object *obj)
|
|
{
|
|
struct bpf_program *prog;
|
|
size_t i;
|
|
int err;
|
|
|
|
for (i = 0; i < obj->nr_programs; i++) {
|
|
prog = &obj->programs[i];
|
|
|
|
err = bpf_program__relocate(prog, obj);
|
|
if (err) {
|
|
pr_warning("failed to relocate '%s'\n",
|
|
prog->section_name);
|
|
return err;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int bpf_object__collect_reloc(struct bpf_object *obj)
|
|
{
|
|
int i, err;
|
|
|
|
if (!obj_elf_valid(obj)) {
|
|
pr_warning("Internal error: elf object is closed\n");
|
|
return -LIBBPF_ERRNO__INTERNAL;
|
|
}
|
|
|
|
for (i = 0; i < obj->efile.nr_reloc; i++) {
|
|
GElf_Shdr *shdr = &obj->efile.reloc[i].shdr;
|
|
Elf_Data *data = obj->efile.reloc[i].data;
|
|
int idx = shdr->sh_info;
|
|
struct bpf_program *prog;
|
|
size_t nr_maps = obj->nr_maps;
|
|
|
|
if (shdr->sh_type != SHT_REL) {
|
|
pr_warning("internal error at %d\n", __LINE__);
|
|
return -LIBBPF_ERRNO__INTERNAL;
|
|
}
|
|
|
|
prog = bpf_object__find_prog_by_idx(obj, idx);
|
|
if (!prog) {
|
|
pr_warning("relocation failed: no %d section\n",
|
|
idx);
|
|
return -LIBBPF_ERRNO__RELOC;
|
|
}
|
|
|
|
err = bpf_program__collect_reloc(prog, nr_maps,
|
|
shdr, data,
|
|
obj->efile.symbols,
|
|
obj->efile.maps_shndx,
|
|
obj->maps);
|
|
if (err)
|
|
return err;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
load_program(enum bpf_prog_type type, struct bpf_insn *insns,
|
|
int insns_cnt, char *license, u32 kern_version, int *pfd)
|
|
{
|
|
int ret;
|
|
char *log_buf;
|
|
|
|
if (!insns || !insns_cnt)
|
|
return -EINVAL;
|
|
|
|
log_buf = malloc(BPF_LOG_BUF_SIZE);
|
|
if (!log_buf)
|
|
pr_warning("Alloc log buffer for bpf loader error, continue without log\n");
|
|
|
|
ret = bpf_load_program(type, insns, insns_cnt, license,
|
|
kern_version, log_buf, BPF_LOG_BUF_SIZE);
|
|
|
|
if (ret >= 0) {
|
|
*pfd = ret;
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
|
|
ret = -LIBBPF_ERRNO__LOAD;
|
|
pr_warning("load bpf program failed: %s\n", strerror(errno));
|
|
|
|
if (log_buf && log_buf[0] != '\0') {
|
|
ret = -LIBBPF_ERRNO__VERIFY;
|
|
pr_warning("-- BEGIN DUMP LOG ---\n");
|
|
pr_warning("\n%s\n", log_buf);
|
|
pr_warning("-- END LOG --\n");
|
|
} else if (insns_cnt >= BPF_MAXINSNS) {
|
|
pr_warning("Program too large (%d insns), at most %d insns\n",
|
|
insns_cnt, BPF_MAXINSNS);
|
|
ret = -LIBBPF_ERRNO__PROG2BIG;
|
|
} else {
|
|
/* Wrong program type? */
|
|
if (type != BPF_PROG_TYPE_KPROBE) {
|
|
int fd;
|
|
|
|
fd = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns,
|
|
insns_cnt, license, kern_version,
|
|
NULL, 0);
|
|
if (fd >= 0) {
|
|
close(fd);
|
|
ret = -LIBBPF_ERRNO__PROGTYPE;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (log_buf)
|
|
ret = -LIBBPF_ERRNO__KVER;
|
|
}
|
|
|
|
out:
|
|
free(log_buf);
|
|
return ret;
|
|
}
|
|
|
|
static int
|
|
bpf_program__load(struct bpf_program *prog,
|
|
char *license, u32 kern_version)
|
|
{
|
|
int err = 0, fd, i;
|
|
|
|
if (prog->instances.nr < 0 || !prog->instances.fds) {
|
|
if (prog->preprocessor) {
|
|
pr_warning("Internal error: can't load program '%s'\n",
|
|
prog->section_name);
|
|
return -LIBBPF_ERRNO__INTERNAL;
|
|
}
|
|
|
|
prog->instances.fds = malloc(sizeof(int));
|
|
if (!prog->instances.fds) {
|
|
pr_warning("Not enough memory for BPF fds\n");
|
|
return -ENOMEM;
|
|
}
|
|
prog->instances.nr = 1;
|
|
prog->instances.fds[0] = -1;
|
|
}
|
|
|
|
if (!prog->preprocessor) {
|
|
if (prog->instances.nr != 1) {
|
|
pr_warning("Program '%s' is inconsistent: nr(%d) != 1\n",
|
|
prog->section_name, prog->instances.nr);
|
|
}
|
|
err = load_program(prog->type, prog->insns, prog->insns_cnt,
|
|
license, kern_version, &fd);
|
|
if (!err)
|
|
prog->instances.fds[0] = fd;
|
|
goto out;
|
|
}
|
|
|
|
for (i = 0; i < prog->instances.nr; i++) {
|
|
struct bpf_prog_prep_result result;
|
|
bpf_program_prep_t preprocessor = prog->preprocessor;
|
|
|
|
bzero(&result, sizeof(result));
|
|
err = preprocessor(prog, i, prog->insns,
|
|
prog->insns_cnt, &result);
|
|
if (err) {
|
|
pr_warning("Preprocessing the %dth instance of program '%s' failed\n",
|
|
i, prog->section_name);
|
|
goto out;
|
|
}
|
|
|
|
if (!result.new_insn_ptr || !result.new_insn_cnt) {
|
|
pr_debug("Skip loading the %dth instance of program '%s'\n",
|
|
i, prog->section_name);
|
|
prog->instances.fds[i] = -1;
|
|
if (result.pfd)
|
|
*result.pfd = -1;
|
|
continue;
|
|
}
|
|
|
|
err = load_program(prog->type, result.new_insn_ptr,
|
|
result.new_insn_cnt,
|
|
license, kern_version, &fd);
|
|
|
|
if (err) {
|
|
pr_warning("Loading the %dth instance of program '%s' failed\n",
|
|
i, prog->section_name);
|
|
goto out;
|
|
}
|
|
|
|
if (result.pfd)
|
|
*result.pfd = fd;
|
|
prog->instances.fds[i] = fd;
|
|
}
|
|
out:
|
|
if (err)
|
|
pr_warning("failed to load program '%s'\n",
|
|
prog->section_name);
|
|
zfree(&prog->insns);
|
|
prog->insns_cnt = 0;
|
|
return err;
|
|
}
|
|
|
|
static int
|
|
bpf_object__load_progs(struct bpf_object *obj)
|
|
{
|
|
size_t i;
|
|
int err;
|
|
|
|
for (i = 0; i < obj->nr_programs; i++) {
|
|
err = bpf_program__load(&obj->programs[i],
|
|
obj->license,
|
|
obj->kern_version);
|
|
if (err)
|
|
return err;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int bpf_object__validate(struct bpf_object *obj)
|
|
{
|
|
if (obj->kern_version == 0) {
|
|
pr_warning("%s doesn't provide kernel version\n",
|
|
obj->path);
|
|
return -LIBBPF_ERRNO__KVERSION;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static struct bpf_object *
|
|
__bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz)
|
|
{
|
|
struct bpf_object *obj;
|
|
int err;
|
|
|
|
if (elf_version(EV_CURRENT) == EV_NONE) {
|
|
pr_warning("failed to init libelf for %s\n", path);
|
|
return ERR_PTR(-LIBBPF_ERRNO__LIBELF);
|
|
}
|
|
|
|
obj = bpf_object__new(path, obj_buf, obj_buf_sz);
|
|
if (IS_ERR(obj))
|
|
return obj;
|
|
|
|
CHECK_ERR(bpf_object__elf_init(obj), err, out);
|
|
CHECK_ERR(bpf_object__check_endianness(obj), err, out);
|
|
CHECK_ERR(bpf_object__elf_collect(obj), err, out);
|
|
CHECK_ERR(bpf_object__collect_reloc(obj), err, out);
|
|
CHECK_ERR(bpf_object__validate(obj), err, out);
|
|
|
|
bpf_object__elf_finish(obj);
|
|
return obj;
|
|
out:
|
|
bpf_object__close(obj);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
struct bpf_object *bpf_object__open(const char *path)
|
|
{
|
|
/* param validation */
|
|
if (!path)
|
|
return NULL;
|
|
|
|
pr_debug("loading %s\n", path);
|
|
|
|
return __bpf_object__open(path, NULL, 0);
|
|
}
|
|
|
|
struct bpf_object *bpf_object__open_buffer(void *obj_buf,
|
|
size_t obj_buf_sz,
|
|
const char *name)
|
|
{
|
|
char tmp_name[64];
|
|
|
|
/* param validation */
|
|
if (!obj_buf || obj_buf_sz <= 0)
|
|
return NULL;
|
|
|
|
if (!name) {
|
|
snprintf(tmp_name, sizeof(tmp_name), "%lx-%lx",
|
|
(unsigned long)obj_buf,
|
|
(unsigned long)obj_buf_sz);
|
|
tmp_name[sizeof(tmp_name) - 1] = '\0';
|
|
name = tmp_name;
|
|
}
|
|
pr_debug("loading object '%s' from buffer\n",
|
|
name);
|
|
|
|
return __bpf_object__open(name, obj_buf, obj_buf_sz);
|
|
}
|
|
|
|
int bpf_object__unload(struct bpf_object *obj)
|
|
{
|
|
size_t i;
|
|
|
|
if (!obj)
|
|
return -EINVAL;
|
|
|
|
for (i = 0; i < obj->nr_maps; i++)
|
|
zclose(obj->maps[i].fd);
|
|
|
|
for (i = 0; i < obj->nr_programs; i++)
|
|
bpf_program__unload(&obj->programs[i]);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int bpf_object__load(struct bpf_object *obj)
|
|
{
|
|
int err;
|
|
|
|
if (!obj)
|
|
return -EINVAL;
|
|
|
|
if (obj->loaded) {
|
|
pr_warning("object should not be loaded twice\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
obj->loaded = true;
|
|
|
|
CHECK_ERR(bpf_object__create_maps(obj), err, out);
|
|
CHECK_ERR(bpf_object__relocate(obj), err, out);
|
|
CHECK_ERR(bpf_object__load_progs(obj), err, out);
|
|
|
|
return 0;
|
|
out:
|
|
bpf_object__unload(obj);
|
|
pr_warning("failed to load object '%s'\n", obj->path);
|
|
return err;
|
|
}
|
|
|
|
static int check_path(const char *path)
|
|
{
|
|
struct statfs st_fs;
|
|
char *dname, *dir;
|
|
int err = 0;
|
|
|
|
if (path == NULL)
|
|
return -EINVAL;
|
|
|
|
dname = strdup(path);
|
|
if (dname == NULL)
|
|
return -ENOMEM;
|
|
|
|
dir = dirname(dname);
|
|
if (statfs(dir, &st_fs)) {
|
|
pr_warning("failed to statfs %s: %s\n", dir, strerror(errno));
|
|
err = -errno;
|
|
}
|
|
free(dname);
|
|
|
|
if (!err && st_fs.f_type != BPF_FS_MAGIC) {
|
|
pr_warning("specified path %s is not on BPF FS\n", path);
|
|
err = -EINVAL;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
int bpf_program__pin_instance(struct bpf_program *prog, const char *path,
|
|
int instance)
|
|
{
|
|
int err;
|
|
|
|
err = check_path(path);
|
|
if (err)
|
|
return err;
|
|
|
|
if (prog == NULL) {
|
|
pr_warning("invalid program pointer\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (instance < 0 || instance >= prog->instances.nr) {
|
|
pr_warning("invalid prog instance %d of prog %s (max %d)\n",
|
|
instance, prog->section_name, prog->instances.nr);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (bpf_obj_pin(prog->instances.fds[instance], path)) {
|
|
pr_warning("failed to pin program: %s\n", strerror(errno));
|
|
return -errno;
|
|
}
|
|
pr_debug("pinned program '%s'\n", path);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int make_dir(const char *path)
|
|
{
|
|
int err = 0;
|
|
|
|
if (mkdir(path, 0700) && errno != EEXIST)
|
|
err = -errno;
|
|
|
|
if (err)
|
|
pr_warning("failed to mkdir %s: %s\n", path, strerror(-err));
|
|
return err;
|
|
}
|
|
|
|
int bpf_program__pin(struct bpf_program *prog, const char *path)
|
|
{
|
|
int i, err;
|
|
|
|
err = check_path(path);
|
|
if (err)
|
|
return err;
|
|
|
|
if (prog == NULL) {
|
|
pr_warning("invalid program pointer\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (prog->instances.nr <= 0) {
|
|
pr_warning("no instances of prog %s to pin\n",
|
|
prog->section_name);
|
|
return -EINVAL;
|
|
}
|
|
|
|
err = make_dir(path);
|
|
if (err)
|
|
return err;
|
|
|
|
for (i = 0; i < prog->instances.nr; i++) {
|
|
char buf[PATH_MAX];
|
|
int len;
|
|
|
|
len = snprintf(buf, PATH_MAX, "%s/%d", path, i);
|
|
if (len < 0)
|
|
return -EINVAL;
|
|
else if (len >= PATH_MAX)
|
|
return -ENAMETOOLONG;
|
|
|
|
err = bpf_program__pin_instance(prog, buf, i);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int bpf_map__pin(struct bpf_map *map, const char *path)
|
|
{
|
|
int err;
|
|
|
|
err = check_path(path);
|
|
if (err)
|
|
return err;
|
|
|
|
if (map == NULL) {
|
|
pr_warning("invalid map pointer\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (bpf_obj_pin(map->fd, path)) {
|
|
pr_warning("failed to pin map: %s\n", strerror(errno));
|
|
return -errno;
|
|
}
|
|
|
|
pr_debug("pinned map '%s'\n", path);
|
|
return 0;
|
|
}
|
|
|
|
int bpf_object__pin(struct bpf_object *obj, const char *path)
|
|
{
|
|
struct bpf_program *prog;
|
|
struct bpf_map *map;
|
|
int err;
|
|
|
|
if (!obj)
|
|
return -ENOENT;
|
|
|
|
if (!obj->loaded) {
|
|
pr_warning("object not yet loaded; load it first\n");
|
|
return -ENOENT;
|
|
}
|
|
|
|
err = make_dir(path);
|
|
if (err)
|
|
return err;
|
|
|
|
bpf_map__for_each(map, obj) {
|
|
char buf[PATH_MAX];
|
|
int len;
|
|
|
|
len = snprintf(buf, PATH_MAX, "%s/%s", path,
|
|
bpf_map__name(map));
|
|
if (len < 0)
|
|
return -EINVAL;
|
|
else if (len >= PATH_MAX)
|
|
return -ENAMETOOLONG;
|
|
|
|
err = bpf_map__pin(map, buf);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
bpf_object__for_each_program(prog, obj) {
|
|
char buf[PATH_MAX];
|
|
int len;
|
|
|
|
len = snprintf(buf, PATH_MAX, "%s/%s", path,
|
|
prog->section_name);
|
|
if (len < 0)
|
|
return -EINVAL;
|
|
else if (len >= PATH_MAX)
|
|
return -ENAMETOOLONG;
|
|
|
|
err = bpf_program__pin(prog, buf);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void bpf_object__close(struct bpf_object *obj)
|
|
{
|
|
size_t i;
|
|
|
|
if (!obj)
|
|
return;
|
|
|
|
if (obj->clear_priv)
|
|
obj->clear_priv(obj, obj->priv);
|
|
|
|
bpf_object__elf_finish(obj);
|
|
bpf_object__unload(obj);
|
|
|
|
for (i = 0; i < obj->nr_maps; i++) {
|
|
zfree(&obj->maps[i].name);
|
|
if (obj->maps[i].clear_priv)
|
|
obj->maps[i].clear_priv(&obj->maps[i],
|
|
obj->maps[i].priv);
|
|
obj->maps[i].priv = NULL;
|
|
obj->maps[i].clear_priv = NULL;
|
|
}
|
|
zfree(&obj->maps);
|
|
obj->nr_maps = 0;
|
|
|
|
if (obj->programs && obj->nr_programs) {
|
|
for (i = 0; i < obj->nr_programs; i++)
|
|
bpf_program__exit(&obj->programs[i]);
|
|
}
|
|
zfree(&obj->programs);
|
|
|
|
list_del(&obj->list);
|
|
free(obj);
|
|
}
|
|
|
|
struct bpf_object *
|
|
bpf_object__next(struct bpf_object *prev)
|
|
{
|
|
struct bpf_object *next;
|
|
|
|
if (!prev)
|
|
next = list_first_entry(&bpf_objects_list,
|
|
struct bpf_object,
|
|
list);
|
|
else
|
|
next = list_next_entry(prev, list);
|
|
|
|
/* Empty list is noticed here so don't need checking on entry. */
|
|
if (&next->list == &bpf_objects_list)
|
|
return NULL;
|
|
|
|
return next;
|
|
}
|
|
|
|
const char *bpf_object__name(struct bpf_object *obj)
|
|
{
|
|
return obj ? obj->path : ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
unsigned int bpf_object__kversion(struct bpf_object *obj)
|
|
{
|
|
return obj ? obj->kern_version : 0;
|
|
}
|
|
|
|
int bpf_object__set_priv(struct bpf_object *obj, void *priv,
|
|
bpf_object_clear_priv_t clear_priv)
|
|
{
|
|
if (obj->priv && obj->clear_priv)
|
|
obj->clear_priv(obj, obj->priv);
|
|
|
|
obj->priv = priv;
|
|
obj->clear_priv = clear_priv;
|
|
return 0;
|
|
}
|
|
|
|
void *bpf_object__priv(struct bpf_object *obj)
|
|
{
|
|
return obj ? obj->priv : ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
struct bpf_program *
|
|
bpf_program__next(struct bpf_program *prev, struct bpf_object *obj)
|
|
{
|
|
size_t idx;
|
|
|
|
if (!obj->programs)
|
|
return NULL;
|
|
/* First handler */
|
|
if (prev == NULL)
|
|
return &obj->programs[0];
|
|
|
|
if (prev->obj != obj) {
|
|
pr_warning("error: program handler doesn't match object\n");
|
|
return NULL;
|
|
}
|
|
|
|
idx = (prev - obj->programs) + 1;
|
|
if (idx >= obj->nr_programs)
|
|
return NULL;
|
|
return &obj->programs[idx];
|
|
}
|
|
|
|
int bpf_program__set_priv(struct bpf_program *prog, void *priv,
|
|
bpf_program_clear_priv_t clear_priv)
|
|
{
|
|
if (prog->priv && prog->clear_priv)
|
|
prog->clear_priv(prog, prog->priv);
|
|
|
|
prog->priv = priv;
|
|
prog->clear_priv = clear_priv;
|
|
return 0;
|
|
}
|
|
|
|
void *bpf_program__priv(struct bpf_program *prog)
|
|
{
|
|
return prog ? prog->priv : ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
const char *bpf_program__title(struct bpf_program *prog, bool needs_copy)
|
|
{
|
|
const char *title;
|
|
|
|
title = prog->section_name;
|
|
if (needs_copy) {
|
|
title = strdup(title);
|
|
if (!title) {
|
|
pr_warning("failed to strdup program title\n");
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
}
|
|
|
|
return title;
|
|
}
|
|
|
|
int bpf_program__fd(struct bpf_program *prog)
|
|
{
|
|
return bpf_program__nth_fd(prog, 0);
|
|
}
|
|
|
|
int bpf_program__set_prep(struct bpf_program *prog, int nr_instances,
|
|
bpf_program_prep_t prep)
|
|
{
|
|
int *instances_fds;
|
|
|
|
if (nr_instances <= 0 || !prep)
|
|
return -EINVAL;
|
|
|
|
if (prog->instances.nr > 0 || prog->instances.fds) {
|
|
pr_warning("Can't set pre-processor after loading\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
instances_fds = malloc(sizeof(int) * nr_instances);
|
|
if (!instances_fds) {
|
|
pr_warning("alloc memory failed for fds\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* fill all fd with -1 */
|
|
memset(instances_fds, -1, sizeof(int) * nr_instances);
|
|
|
|
prog->instances.nr = nr_instances;
|
|
prog->instances.fds = instances_fds;
|
|
prog->preprocessor = prep;
|
|
return 0;
|
|
}
|
|
|
|
int bpf_program__nth_fd(struct bpf_program *prog, int n)
|
|
{
|
|
int fd;
|
|
|
|
if (n >= prog->instances.nr || n < 0) {
|
|
pr_warning("Can't get the %dth fd from program %s: only %d instances\n",
|
|
n, prog->section_name, prog->instances.nr);
|
|
return -EINVAL;
|
|
}
|
|
|
|
fd = prog->instances.fds[n];
|
|
if (fd < 0) {
|
|
pr_warning("%dth instance of program '%s' is invalid\n",
|
|
n, prog->section_name);
|
|
return -ENOENT;
|
|
}
|
|
|
|
return fd;
|
|
}
|
|
|
|
void bpf_program__set_type(struct bpf_program *prog, enum bpf_prog_type type)
|
|
{
|
|
prog->type = type;
|
|
}
|
|
|
|
static bool bpf_program__is_type(struct bpf_program *prog,
|
|
enum bpf_prog_type type)
|
|
{
|
|
return prog ? (prog->type == type) : false;
|
|
}
|
|
|
|
#define BPF_PROG_TYPE_FNS(NAME, TYPE) \
|
|
int bpf_program__set_##NAME(struct bpf_program *prog) \
|
|
{ \
|
|
if (!prog) \
|
|
return -EINVAL; \
|
|
bpf_program__set_type(prog, TYPE); \
|
|
return 0; \
|
|
} \
|
|
\
|
|
bool bpf_program__is_##NAME(struct bpf_program *prog) \
|
|
{ \
|
|
return bpf_program__is_type(prog, TYPE); \
|
|
} \
|
|
|
|
BPF_PROG_TYPE_FNS(socket_filter, BPF_PROG_TYPE_SOCKET_FILTER);
|
|
BPF_PROG_TYPE_FNS(kprobe, BPF_PROG_TYPE_KPROBE);
|
|
BPF_PROG_TYPE_FNS(sched_cls, BPF_PROG_TYPE_SCHED_CLS);
|
|
BPF_PROG_TYPE_FNS(sched_act, BPF_PROG_TYPE_SCHED_ACT);
|
|
BPF_PROG_TYPE_FNS(tracepoint, BPF_PROG_TYPE_TRACEPOINT);
|
|
BPF_PROG_TYPE_FNS(xdp, BPF_PROG_TYPE_XDP);
|
|
BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT);
|
|
|
|
int bpf_map__fd(struct bpf_map *map)
|
|
{
|
|
return map ? map->fd : -EINVAL;
|
|
}
|
|
|
|
const struct bpf_map_def *bpf_map__def(struct bpf_map *map)
|
|
{
|
|
return map ? &map->def : ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
const char *bpf_map__name(struct bpf_map *map)
|
|
{
|
|
return map ? map->name : NULL;
|
|
}
|
|
|
|
int bpf_map__set_priv(struct bpf_map *map, void *priv,
|
|
bpf_map_clear_priv_t clear_priv)
|
|
{
|
|
if (!map)
|
|
return -EINVAL;
|
|
|
|
if (map->priv) {
|
|
if (map->clear_priv)
|
|
map->clear_priv(map, map->priv);
|
|
}
|
|
|
|
map->priv = priv;
|
|
map->clear_priv = clear_priv;
|
|
return 0;
|
|
}
|
|
|
|
void *bpf_map__priv(struct bpf_map *map)
|
|
{
|
|
return map ? map->priv : ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
struct bpf_map *
|
|
bpf_map__next(struct bpf_map *prev, struct bpf_object *obj)
|
|
{
|
|
size_t idx;
|
|
struct bpf_map *s, *e;
|
|
|
|
if (!obj || !obj->maps)
|
|
return NULL;
|
|
|
|
s = obj->maps;
|
|
e = obj->maps + obj->nr_maps;
|
|
|
|
if (prev == NULL)
|
|
return s;
|
|
|
|
if ((prev < s) || (prev >= e)) {
|
|
pr_warning("error in %s: map handler doesn't belong to object\n",
|
|
__func__);
|
|
return NULL;
|
|
}
|
|
|
|
idx = (prev - obj->maps) + 1;
|
|
if (idx >= obj->nr_maps)
|
|
return NULL;
|
|
return &obj->maps[idx];
|
|
}
|
|
|
|
struct bpf_map *
|
|
bpf_object__find_map_by_name(struct bpf_object *obj, const char *name)
|
|
{
|
|
struct bpf_map *pos;
|
|
|
|
bpf_map__for_each(pos, obj) {
|
|
if (pos->name && !strcmp(pos->name, name))
|
|
return pos;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
struct bpf_map *
|
|
bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < obj->nr_maps; i++) {
|
|
if (obj->maps[i].offset == offset)
|
|
return &obj->maps[i];
|
|
}
|
|
return ERR_PTR(-ENOENT);
|
|
}
|
|
|
|
long libbpf_get_error(const void *ptr)
|
|
{
|
|
if (IS_ERR(ptr))
|
|
return PTR_ERR(ptr);
|
|
return 0;
|
|
}
|