| // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) |
| |
| /* |
| * 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. |
| * Copyright (C) 2019 Isovalent, Inc. |
| */ |
| |
| #ifndef _GNU_SOURCE |
| #define _GNU_SOURCE |
| #endif |
| #include <stdlib.h> |
| #include <stdio.h> |
| #include <stdarg.h> |
| #include <libgen.h> |
| #include <inttypes.h> |
| #include <string.h> |
| #include <unistd.h> |
| #include <endian.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/btf.h> |
| #include <linux/filter.h> |
| #include <linux/list.h> |
| #include <linux/limits.h> |
| #include <linux/perf_event.h> |
| #include <linux/ring_buffer.h> |
| #include <sys/epoll.h> |
| #include <sys/ioctl.h> |
| #include <sys/mman.h> |
| #include <sys/stat.h> |
| #include <sys/types.h> |
| #include <sys/vfs.h> |
| #include <tools/libc_compat.h> |
| #include <libelf.h> |
| #include <gelf.h> |
| |
| #include "libbpf.h" |
| #include "bpf.h" |
| #include "btf.h" |
| #include "str_error.h" |
| #include "libbpf_internal.h" |
| |
| #ifndef EM_BPF |
| #define EM_BPF 247 |
| #endif |
| |
| #ifndef BPF_FS_MAGIC |
| #define BPF_FS_MAGIC 0xcafe4a11 |
| #endif |
| |
| /* vsprintf() in __base_pr() uses nonliteral format string. It may break |
| * compilation if user enables corresponding warning. Disable it explicitly. |
| */ |
| #pragma GCC diagnostic ignored "-Wformat-nonliteral" |
| |
| #define __printf(a, b) __attribute__((format(printf, a, b))) |
| |
| static int __base_pr(enum libbpf_print_level level, const char *format, |
| va_list args) |
| { |
| if (level == LIBBPF_DEBUG) |
| return 0; |
| |
| return vfprintf(stderr, format, args); |
| } |
| |
| static libbpf_print_fn_t __libbpf_pr = __base_pr; |
| |
| void libbpf_set_print(libbpf_print_fn_t fn) |
| { |
| __libbpf_pr = fn; |
| } |
| |
| __printf(2, 3) |
| void libbpf_print(enum libbpf_print_level level, const char *format, ...) |
| { |
| va_list args; |
| |
| if (!__libbpf_pr) |
| return; |
| |
| va_start(args, format); |
| __libbpf_pr(level, format, args); |
| va_end(args); |
| } |
| |
| #define STRERR_BUFSIZE 128 |
| |
| #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 |
| |
| static inline __u64 ptr_to_u64(const void *ptr) |
| { |
| return (__u64) (unsigned long) ptr; |
| } |
| |
| struct bpf_capabilities { |
| /* v4.14: kernel support for program & map names. */ |
| __u32 name:1; |
| /* v5.2: kernel support for global data sections. */ |
| __u32 global_data:1; |
| /* BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO support */ |
| __u32 btf_func:1; |
| /* BTF_KIND_VAR and BTF_KIND_DATASEC support */ |
| __u32 btf_datasec:1; |
| }; |
| |
| /* |
| * 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 *name; |
| int prog_ifindex; |
| char *section_name; |
| /* section_name with / replaced by _; makes recursive pinning |
| * in bpf_object__pin_programs easier |
| */ |
| char *pin_name; |
| struct bpf_insn *insns; |
| size_t insns_cnt, main_prog_cnt; |
| enum bpf_prog_type type; |
| |
| struct reloc_desc { |
| enum { |
| RELO_LD64, |
| RELO_CALL, |
| RELO_DATA, |
| } type; |
| int insn_idx; |
| union { |
| int map_idx; |
| int text_off; |
| }; |
| } *reloc_desc; |
| int nr_reloc; |
| int log_level; |
| |
| struct { |
| int nr; |
| int *fds; |
| } instances; |
| bpf_program_prep_t preprocessor; |
| |
| struct bpf_object *obj; |
| void *priv; |
| bpf_program_clear_priv_t clear_priv; |
| |
| enum bpf_attach_type expected_attach_type; |
| void *func_info; |
| __u32 func_info_rec_size; |
| __u32 func_info_cnt; |
| |
| struct bpf_capabilities *caps; |
| |
| void *line_info; |
| __u32 line_info_rec_size; |
| __u32 line_info_cnt; |
| __u32 prog_flags; |
| }; |
| |
| enum libbpf_map_type { |
| LIBBPF_MAP_UNSPEC, |
| LIBBPF_MAP_DATA, |
| LIBBPF_MAP_BSS, |
| LIBBPF_MAP_RODATA, |
| }; |
| |
| static const char * const libbpf_type_to_btf_name[] = { |
| [LIBBPF_MAP_DATA] = ".data", |
| [LIBBPF_MAP_BSS] = ".bss", |
| [LIBBPF_MAP_RODATA] = ".rodata", |
| }; |
| |
| struct bpf_map { |
| int fd; |
| char *name; |
| int sec_idx; |
| size_t sec_offset; |
| int map_ifindex; |
| int inner_map_fd; |
| struct bpf_map_def def; |
| __u32 btf_key_type_id; |
| __u32 btf_value_type_id; |
| void *priv; |
| bpf_map_clear_priv_t clear_priv; |
| enum libbpf_map_type libbpf_type; |
| }; |
| |
| struct bpf_secdata { |
| void *rodata; |
| void *data; |
| }; |
| |
| static LIST_HEAD(bpf_objects_list); |
| |
| struct bpf_object { |
| char name[BPF_OBJ_NAME_LEN]; |
| char license[64]; |
| __u32 kern_version; |
| |
| struct bpf_program *programs; |
| size_t nr_programs; |
| struct bpf_map *maps; |
| size_t nr_maps; |
| size_t maps_cap; |
| struct bpf_secdata sections; |
| |
| bool loaded; |
| bool has_pseudo_calls; |
| |
| /* |
| * 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; |
| Elf_Data *data; |
| Elf_Data *rodata; |
| Elf_Data *bss; |
| size_t strtabidx; |
| struct { |
| GElf_Shdr shdr; |
| Elf_Data *data; |
| } *reloc; |
| int nr_reloc; |
| int maps_shndx; |
| int btf_maps_shndx; |
| int text_shndx; |
| int data_shndx; |
| int rodata_shndx; |
| int bss_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; |
| |
| struct btf *btf; |
| struct btf_ext *btf_ext; |
| |
| void *priv; |
| bpf_object_clear_priv_t clear_priv; |
| |
| struct bpf_capabilities caps; |
| |
| char path[]; |
| }; |
| #define obj_elf_valid(o) ((o)->efile.elf) |
| |
| 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); |
| |
| zfree(&prog->func_info); |
| zfree(&prog->line_info); |
| } |
| |
| 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->name); |
| zfree(&prog->section_name); |
| zfree(&prog->pin_name); |
| zfree(&prog->insns); |
| zfree(&prog->reloc_desc); |
| |
| prog->nr_reloc = 0; |
| prog->insns_cnt = 0; |
| prog->idx = -1; |
| } |
| |
| static char *__bpf_program__pin_name(struct bpf_program *prog) |
| { |
| char *name, *p; |
| |
| name = p = strdup(prog->section_name); |
| while ((p = strchr(p, '/'))) |
| *p = '_'; |
| |
| return name; |
| } |
| |
| static int |
| bpf_program__init(void *data, size_t size, char *section_name, int idx, |
| struct bpf_program *prog) |
| { |
| const size_t bpf_insn_sz = sizeof(struct bpf_insn); |
| |
| if (size == 0 || size % bpf_insn_sz) { |
| pr_warning("corrupted section '%s', size: %zu\n", |
| section_name, size); |
| return -EINVAL; |
| } |
| |
| memset(prog, 0, sizeof(*prog)); |
| |
| prog->section_name = strdup(section_name); |
| if (!prog->section_name) { |
| pr_warning("failed to alloc name for prog under section(%d) %s\n", |
| idx, section_name); |
| goto errout; |
| } |
| |
| prog->pin_name = __bpf_program__pin_name(prog); |
| if (!prog->pin_name) { |
| pr_warning("failed to alloc pin name for prog under section(%d) %s\n", |
| idx, section_name); |
| goto errout; |
| } |
| |
| prog->insns = malloc(size); |
| if (!prog->insns) { |
| pr_warning("failed to alloc insns for prog under section %s\n", |
| section_name); |
| goto errout; |
| } |
| prog->insns_cnt = size / bpf_insn_sz; |
| memcpy(prog->insns, data, size); |
| prog->idx = idx; |
| prog->instances.fds = NULL; |
| prog->instances.nr = -1; |
| prog->type = BPF_PROG_TYPE_UNSPEC; |
| |
| 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 *section_name, int idx) |
| { |
| struct bpf_program prog, *progs; |
| int nr_progs, err; |
| |
| err = bpf_program__init(data, size, section_name, idx, &prog); |
| if (err) |
| return err; |
| |
| prog.caps = &obj->caps; |
| progs = obj->programs; |
| nr_progs = obj->nr_programs; |
| |
| progs = reallocarray(progs, nr_progs + 1, sizeof(progs[0])); |
| 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 under section '%s'\n", |
| section_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 int |
| bpf_object__init_prog_names(struct bpf_object *obj) |
| { |
| Elf_Data *symbols = obj->efile.symbols; |
| struct bpf_program *prog; |
| size_t pi, si; |
| |
| for (pi = 0; pi < obj->nr_programs; pi++) { |
| const char *name = NULL; |
| |
| prog = &obj->programs[pi]; |
| |
| for (si = 0; si < symbols->d_size / sizeof(GElf_Sym) && !name; |
| si++) { |
| GElf_Sym sym; |
| |
| if (!gelf_getsym(symbols, si, &sym)) |
| continue; |
| if (sym.st_shndx != prog->idx) |
| continue; |
| if (GELF_ST_BIND(sym.st_info) != STB_GLOBAL) |
| continue; |
| |
| name = elf_strptr(obj->efile.elf, |
| obj->efile.strtabidx, |
| sym.st_name); |
| if (!name) { |
| pr_warning("failed to get sym name string for prog %s\n", |
| prog->section_name); |
| return -LIBBPF_ERRNO__LIBELF; |
| } |
| } |
| |
| if (!name && prog->idx == obj->efile.text_shndx) |
| name = ".text"; |
| |
| if (!name) { |
| pr_warning("failed to find sym for prog %s\n", |
| prog->section_name); |
| return -EINVAL; |
| } |
| |
| prog->name = strdup(name); |
| if (!prog->name) { |
| pr_warning("failed to allocate memory for prog sym %s\n", |
| name); |
| return -ENOMEM; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static struct bpf_object *bpf_object__new(const char *path, |
| void *obj_buf, |
| size_t obj_buf_sz) |
| { |
| struct bpf_object *obj; |
| char *end; |
| |
| 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); |
| /* Using basename() GNU version which doesn't modify arg. */ |
| strncpy(obj->name, basename((void *)path), sizeof(obj->name) - 1); |
| end = strchr(obj->name, '.'); |
| if (end) |
| *end = 0; |
| |
| obj->efile.fd = -1; |
| /* |
| * Caller of this function should also call |
| * 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->efile.btf_maps_shndx = -1; |
| obj->efile.data_shndx = -1; |
| obj->efile.rodata_shndx = -1; |
| obj->efile.bss_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; |
| obj->efile.data = NULL; |
| obj->efile.rodata = NULL; |
| obj->efile.bss = 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) { |
| char errmsg[STRERR_BUFSIZE], *cp; |
| |
| err = -errno; |
| cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); |
| pr_warning("failed to open %s: %s\n", obj->path, cp); |
| return err; |
| } |
| |
| 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) |
| { |
| #if __BYTE_ORDER == __LITTLE_ENDIAN |
| if (obj->efile.ehdr.e_ident[EI_DATA] == ELFDATA2LSB) |
| return 0; |
| #elif __BYTE_ORDER == __BIG_ENDIAN |
| if (obj->efile.ehdr.e_ident[EI_DATA] == ELFDATA2MSB) |
| return 0; |
| #else |
| # error "Unrecognized __BYTE_ORDER__" |
| #endif |
| pr_warning("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 compare_bpf_map(const void *_a, const void *_b) |
| { |
| const struct bpf_map *a = _a; |
| const struct bpf_map *b = _b; |
| |
| if (a->sec_idx != b->sec_idx) |
| return a->sec_idx - b->sec_idx; |
| return a->sec_offset - b->sec_offset; |
| } |
| |
| static bool bpf_map_type__is_map_in_map(enum bpf_map_type type) |
| { |
| if (type == BPF_MAP_TYPE_ARRAY_OF_MAPS || |
| type == BPF_MAP_TYPE_HASH_OF_MAPS) |
| return true; |
| return false; |
| } |
| |
| static int bpf_object_search_section_size(const struct bpf_object *obj, |
| const char *name, size_t *d_size) |
| { |
| const GElf_Ehdr *ep = &obj->efile.ehdr; |
| Elf *elf = obj->efile.elf; |
| Elf_Scn *scn = NULL; |
| int idx = 0; |
| |
| while ((scn = elf_nextscn(elf, scn)) != NULL) { |
| const char *sec_name; |
| Elf_Data *data; |
| GElf_Shdr sh; |
| |
| idx++; |
| if (gelf_getshdr(scn, &sh) != &sh) { |
| pr_warning("failed to get section(%d) header from %s\n", |
| idx, obj->path); |
| return -EIO; |
| } |
| |
| sec_name = elf_strptr(elf, ep->e_shstrndx, sh.sh_name); |
| if (!sec_name) { |
| pr_warning("failed to get section(%d) name from %s\n", |
| idx, obj->path); |
| return -EIO; |
| } |
| |
| if (strcmp(name, sec_name)) |
| continue; |
| |
| data = elf_getdata(scn, 0); |
| if (!data) { |
| pr_warning("failed to get section(%d) data from %s(%s)\n", |
| idx, name, obj->path); |
| return -EIO; |
| } |
| |
| *d_size = data->d_size; |
| return 0; |
| } |
| |
| return -ENOENT; |
| } |
| |
| int bpf_object__section_size(const struct bpf_object *obj, const char *name, |
| __u32 *size) |
| { |
| int ret = -ENOENT; |
| size_t d_size; |
| |
| *size = 0; |
| if (!name) { |
| return -EINVAL; |
| } else if (!strcmp(name, ".data")) { |
| if (obj->efile.data) |
| *size = obj->efile.data->d_size; |
| } else if (!strcmp(name, ".bss")) { |
| if (obj->efile.bss) |
| *size = obj->efile.bss->d_size; |
| } else if (!strcmp(name, ".rodata")) { |
| if (obj->efile.rodata) |
| *size = obj->efile.rodata->d_size; |
| } else { |
| ret = bpf_object_search_section_size(obj, name, &d_size); |
| if (!ret) |
| *size = d_size; |
| } |
| |
| return *size ? 0 : ret; |
| } |
| |
| int bpf_object__variable_offset(const struct bpf_object *obj, const char *name, |
| __u32 *off) |
| { |
| Elf_Data *symbols = obj->efile.symbols; |
| const char *sname; |
| size_t si; |
| |
| if (!name || !off) |
| return -EINVAL; |
| |
| for (si = 0; si < symbols->d_size / sizeof(GElf_Sym); si++) { |
| GElf_Sym sym; |
| |
| if (!gelf_getsym(symbols, si, &sym)) |
| continue; |
| if (GELF_ST_BIND(sym.st_info) != STB_GLOBAL || |
| GELF_ST_TYPE(sym.st_info) != STT_OBJECT) |
| continue; |
| |
| sname = elf_strptr(obj->efile.elf, obj->efile.strtabidx, |
| sym.st_name); |
| if (!sname) { |
| pr_warning("failed to get sym name string for var %s\n", |
| name); |
| return -EIO; |
| } |
| if (strcmp(name, sname) == 0) { |
| *off = sym.st_value; |
| return 0; |
| } |
| } |
| |
| return -ENOENT; |
| } |
| |
| static struct bpf_map *bpf_object__add_map(struct bpf_object *obj) |
| { |
| struct bpf_map *new_maps; |
| size_t new_cap; |
| int i; |
| |
| if (obj->nr_maps < obj->maps_cap) |
| return &obj->maps[obj->nr_maps++]; |
| |
| new_cap = max((size_t)4, obj->maps_cap * 3 / 2); |
| new_maps = realloc(obj->maps, new_cap * sizeof(*obj->maps)); |
| if (!new_maps) { |
| pr_warning("alloc maps for object failed\n"); |
| return ERR_PTR(-ENOMEM); |
| } |
| |
| obj->maps_cap = new_cap; |
| obj->maps = new_maps; |
| |
| /* zero out new maps */ |
| memset(obj->maps + obj->nr_maps, 0, |
| (obj->maps_cap - obj->nr_maps) * sizeof(*obj->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 = obj->nr_maps; i < obj->maps_cap; i++) { |
| obj->maps[i].fd = -1; |
| obj->maps[i].inner_map_fd = -1; |
| } |
| |
| return &obj->maps[obj->nr_maps++]; |
| } |
| |
| static int |
| bpf_object__init_internal_map(struct bpf_object *obj, enum libbpf_map_type type, |
| int sec_idx, Elf_Data *data, void **data_buff) |
| { |
| char map_name[BPF_OBJ_NAME_LEN]; |
| struct bpf_map_def *def; |
| struct bpf_map *map; |
| |
| map = bpf_object__add_map(obj); |
| if (IS_ERR(map)) |
| return PTR_ERR(map); |
| |
| map->libbpf_type = type; |
| map->sec_idx = sec_idx; |
| map->sec_offset = 0; |
| snprintf(map_name, sizeof(map_name), "%.8s%.7s", obj->name, |
| libbpf_type_to_btf_name[type]); |
| map->name = strdup(map_name); |
| if (!map->name) { |
| pr_warning("failed to alloc map name\n"); |
| return -ENOMEM; |
| } |
| pr_debug("map '%s' (global data): at sec_idx %d, offset %zu.\n", |
| map_name, map->sec_idx, map->sec_offset); |
| |
| def = &map->def; |
| def->type = BPF_MAP_TYPE_ARRAY; |
| def->key_size = sizeof(int); |
| def->value_size = data->d_size; |
| def->max_entries = 1; |
| def->map_flags = type == LIBBPF_MAP_RODATA ? BPF_F_RDONLY_PROG : 0; |
| if (data_buff) { |
| *data_buff = malloc(data->d_size); |
| if (!*data_buff) { |
| zfree(&map->name); |
| pr_warning("failed to alloc map content buffer\n"); |
| return -ENOMEM; |
| } |
| memcpy(*data_buff, data->d_buf, data->d_size); |
| } |
| |
| pr_debug("map %td is \"%s\"\n", map - obj->maps, map->name); |
| return 0; |
| } |
| |
| static int bpf_object__init_global_data_maps(struct bpf_object *obj) |
| { |
| int err; |
| |
| if (!obj->caps.global_data) |
| return 0; |
| /* |
| * Populate obj->maps with libbpf internal maps. |
| */ |
| if (obj->efile.data_shndx >= 0) { |
| err = bpf_object__init_internal_map(obj, LIBBPF_MAP_DATA, |
| obj->efile.data_shndx, |
| obj->efile.data, |
| &obj->sections.data); |
| if (err) |
| return err; |
| } |
| if (obj->efile.rodata_shndx >= 0) { |
| err = bpf_object__init_internal_map(obj, LIBBPF_MAP_RODATA, |
| obj->efile.rodata_shndx, |
| obj->efile.rodata, |
| &obj->sections.rodata); |
| if (err) |
| return err; |
| } |
| if (obj->efile.bss_shndx >= 0) { |
| err = bpf_object__init_internal_map(obj, LIBBPF_MAP_BSS, |
| obj->efile.bss_shndx, |
| obj->efile.bss, NULL); |
| if (err) |
| return err; |
| } |
| return 0; |
| } |
| |
| static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict) |
| { |
| Elf_Data *symbols = obj->efile.symbols; |
| int i, map_def_sz = 0, nr_maps = 0, nr_syms; |
| Elf_Data *data = NULL; |
| Elf_Scn *scn; |
| |
| if (obj->efile.maps_shndx < 0) |
| return 0; |
| |
| 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. |
| */ |
| nr_syms = symbols->d_size / sizeof(GElf_Sym); |
| for (i = 0; i < nr_syms; i++) { |
| GElf_Sym sym; |
| |
| if (!gelf_getsym(symbols, i, &sym)) |
| continue; |
| if (sym.st_shndx != obj->efile.maps_shndx) |
| continue; |
| nr_maps++; |
| } |
| /* Assume equally sized map definitions */ |
| pr_debug("maps in %s: %d maps in %zd bytes\n", |
| obj->path, nr_maps, data->d_size); |
| |
| map_def_sz = data->d_size / nr_maps; |
| if (!data->d_size || (data->d_size % nr_maps) != 0) { |
| pr_warning("unable to determine map definition size " |
| "section %s, %d maps in %zd bytes\n", |
| obj->path, nr_maps, data->d_size); |
| return -EINVAL; |
| } |
| |
| /* Fill obj->maps using data in "maps" section. */ |
| for (i = 0; i < nr_syms; i++) { |
| GElf_Sym sym; |
| const char *map_name; |
| struct bpf_map_def *def; |
| struct bpf_map *map; |
| |
| if (!gelf_getsym(symbols, i, &sym)) |
| continue; |
| if (sym.st_shndx != obj->efile.maps_shndx) |
| continue; |
| |
| map = bpf_object__add_map(obj); |
| if (IS_ERR(map)) |
| return PTR_ERR(map); |
| |
| map_name = elf_strptr(obj->efile.elf, obj->efile.strtabidx, |
| sym.st_name); |
| if (!map_name) { |
| pr_warning("failed to get map #%d name sym string for obj %s\n", |
| i, obj->path); |
| return -LIBBPF_ERRNO__FORMAT; |
| } |
| |
| map->libbpf_type = LIBBPF_MAP_UNSPEC; |
| map->sec_idx = sym.st_shndx; |
| map->sec_offset = sym.st_value; |
| pr_debug("map '%s' (legacy): at sec_idx %d, offset %zu.\n", |
| map_name, map->sec_idx, map->sec_offset); |
| if (sym.st_value + map_def_sz > data->d_size) { |
| pr_warning("corrupted maps section in %s: last map \"%s\" too small\n", |
| obj->path, map_name); |
| return -EINVAL; |
| } |
| |
| map->name = strdup(map_name); |
| if (!map->name) { |
| pr_warning("failed to alloc map name\n"); |
| return -ENOMEM; |
| } |
| pr_debug("map %d is \"%s\"\n", i, map->name); |
| def = (struct bpf_map_def *)(data->d_buf + sym.st_value); |
| /* |
| * If the definition of the map in the object file fits in |
| * bpf_map_def, copy it. Any extra fields in our version |
| * of bpf_map_def will default to zero as a result of the |
| * calloc above. |
| */ |
| if (map_def_sz <= sizeof(struct bpf_map_def)) { |
| memcpy(&map->def, def, map_def_sz); |
| } else { |
| /* |
| * Here the map structure being read is bigger than what |
| * we expect, truncate if the excess bits are all zero. |
| * If they are not zero, reject this map as |
| * incompatible. |
| */ |
| char *b; |
| for (b = ((char *)def) + sizeof(struct bpf_map_def); |
| b < ((char *)def) + map_def_sz; b++) { |
| if (*b != 0) { |
| pr_warning("maps section in %s: \"%s\" " |
| "has unrecognized, non-zero " |
| "options\n", |
| obj->path, map_name); |
| if (strict) |
| return -EINVAL; |
| } |
| } |
| memcpy(&map->def, def, sizeof(struct bpf_map_def)); |
| } |
| } |
| return 0; |
| } |
| |
| static const struct btf_type *skip_mods_and_typedefs(const struct btf *btf, |
| __u32 id) |
| { |
| const struct btf_type *t = btf__type_by_id(btf, id); |
| |
| while (true) { |
| switch (BTF_INFO_KIND(t->info)) { |
| case BTF_KIND_VOLATILE: |
| case BTF_KIND_CONST: |
| case BTF_KIND_RESTRICT: |
| case BTF_KIND_TYPEDEF: |
| t = btf__type_by_id(btf, t->type); |
| break; |
| default: |
| return t; |
| } |
| } |
| } |
| |
| /* |
| * Fetch integer attribute of BTF map definition. Such attributes are |
| * represented using a pointer to an array, in which dimensionality of array |
| * encodes specified integer value. E.g., int (*type)[BPF_MAP_TYPE_ARRAY]; |
| * encodes `type => BPF_MAP_TYPE_ARRAY` key/value pair completely using BTF |
| * type definition, while using only sizeof(void *) space in ELF data section. |
| */ |
| static bool get_map_field_int(const char *map_name, const struct btf *btf, |
| const struct btf_type *def, |
| const struct btf_member *m, __u32 *res) { |
| const struct btf_type *t = skip_mods_and_typedefs(btf, m->type); |
| const char *name = btf__name_by_offset(btf, m->name_off); |
| const struct btf_array *arr_info; |
| const struct btf_type *arr_t; |
| |
| if (BTF_INFO_KIND(t->info) != BTF_KIND_PTR) { |
| pr_warning("map '%s': attr '%s': expected PTR, got %u.\n", |
| map_name, name, BTF_INFO_KIND(t->info)); |
| return false; |
| } |
| |
| arr_t = btf__type_by_id(btf, t->type); |
| if (!arr_t) { |
| pr_warning("map '%s': attr '%s': type [%u] not found.\n", |
| map_name, name, t->type); |
| return false; |
| } |
| if (BTF_INFO_KIND(arr_t->info) != BTF_KIND_ARRAY) { |
| pr_warning("map '%s': attr '%s': expected ARRAY, got %u.\n", |
| map_name, name, BTF_INFO_KIND(arr_t->info)); |
| return false; |
| } |
| arr_info = (const void *)(arr_t + 1); |
| *res = arr_info->nelems; |
| return true; |
| } |
| |
| static int bpf_object__init_user_btf_map(struct bpf_object *obj, |
| const struct btf_type *sec, |
| int var_idx, int sec_idx, |
| const Elf_Data *data, bool strict) |
| { |
| const struct btf_type *var, *def, *t; |
| const struct btf_var_secinfo *vi; |
| const struct btf_var *var_extra; |
| const struct btf_member *m; |
| const char *map_name; |
| struct bpf_map *map; |
| int vlen, i; |
| |
| vi = (const struct btf_var_secinfo *)(const void *)(sec + 1) + var_idx; |
| var = btf__type_by_id(obj->btf, vi->type); |
| var_extra = (const void *)(var + 1); |
| map_name = btf__name_by_offset(obj->btf, var->name_off); |
| vlen = BTF_INFO_VLEN(var->info); |
| |
| if (map_name == NULL || map_name[0] == '\0') { |
| pr_warning("map #%d: empty name.\n", var_idx); |
| return -EINVAL; |
| } |
| if ((__u64)vi->offset + vi->size > data->d_size) { |
| pr_warning("map '%s' BTF data is corrupted.\n", map_name); |
| return -EINVAL; |
| } |
| if (BTF_INFO_KIND(var->info) != BTF_KIND_VAR) { |
| pr_warning("map '%s': unexpected var kind %u.\n", |
| map_name, BTF_INFO_KIND(var->info)); |
| return -EINVAL; |
| } |
| if (var_extra->linkage != BTF_VAR_GLOBAL_ALLOCATED && |
| var_extra->linkage != BTF_VAR_STATIC) { |
| pr_warning("map '%s': unsupported var linkage %u.\n", |
| map_name, var_extra->linkage); |
| return -EOPNOTSUPP; |
| } |
| |
| def = skip_mods_and_typedefs(obj->btf, var->type); |
| if (BTF_INFO_KIND(def->info) != BTF_KIND_STRUCT) { |
| pr_warning("map '%s': unexpected def kind %u.\n", |
| map_name, BTF_INFO_KIND(var->info)); |
| return -EINVAL; |
| } |
| if (def->size > vi->size) { |
| pr_warning("map '%s': invalid def size.\n", map_name); |
| return -EINVAL; |
| } |
| |
| map = bpf_object__add_map(obj); |
| if (IS_ERR(map)) |
| return PTR_ERR(map); |
| map->name = strdup(map_name); |
| if (!map->name) { |
| pr_warning("map '%s': failed to alloc map name.\n", map_name); |
| return -ENOMEM; |
| } |
| map->libbpf_type = LIBBPF_MAP_UNSPEC; |
| map->def.type = BPF_MAP_TYPE_UNSPEC; |
| map->sec_idx = sec_idx; |
| map->sec_offset = vi->offset; |
| pr_debug("map '%s': at sec_idx %d, offset %zu.\n", |
| map_name, map->sec_idx, map->sec_offset); |
| |
| vlen = BTF_INFO_VLEN(def->info); |
| m = (const void *)(def + 1); |
| for (i = 0; i < vlen; i++, m++) { |
| const char *name = btf__name_by_offset(obj->btf, m->name_off); |
| |
| if (!name) { |
| pr_warning("map '%s': invalid field #%d.\n", |
| map_name, i); |
| return -EINVAL; |
| } |
| if (strcmp(name, "type") == 0) { |
| if (!get_map_field_int(map_name, obj->btf, def, m, |
| &map->def.type)) |
| return -EINVAL; |
| pr_debug("map '%s': found type = %u.\n", |
| map_name, map->def.type); |
| } else if (strcmp(name, "max_entries") == 0) { |
| if (!get_map_field_int(map_name, obj->btf, def, m, |
| &map->def.max_entries)) |
| return -EINVAL; |
| pr_debug("map '%s': found max_entries = %u.\n", |
| map_name, map->def.max_entries); |
| } else if (strcmp(name, "map_flags") == 0) { |
| if (!get_map_field_int(map_name, obj->btf, def, m, |
| &map->def.map_flags)) |
| return -EINVAL; |
| pr_debug("map '%s': found map_flags = %u.\n", |
| map_name, map->def.map_flags); |
| } else if (strcmp(name, "key_size") == 0) { |
| __u32 sz; |
| |
| if (!get_map_field_int(map_name, obj->btf, def, m, |
| &sz)) |
| return -EINVAL; |
| pr_debug("map '%s': found key_size = %u.\n", |
| map_name, sz); |
| if (map->def.key_size && map->def.key_size != sz) { |
| pr_warning("map '%s': conflicting key size %u != %u.\n", |
| map_name, map->def.key_size, sz); |
| return -EINVAL; |
| } |
| map->def.key_size = sz; |
| } else if (strcmp(name, "key") == 0) { |
| __s64 sz; |
| |
| t = btf__type_by_id(obj->btf, m->type); |
| if (!t) { |
| pr_warning("map '%s': key type [%d] not found.\n", |
| map_name, m->type); |
| return -EINVAL; |
| } |
| if (BTF_INFO_KIND(t->info) != BTF_KIND_PTR) { |
| pr_warning("map '%s': key spec is not PTR: %u.\n", |
| map_name, BTF_INFO_KIND(t->info)); |
| return -EINVAL; |
| } |
| sz = btf__resolve_size(obj->btf, t->type); |
| if (sz < 0) { |
| pr_warning("map '%s': can't determine key size for type [%u]: %lld.\n", |
| map_name, t->type, sz); |
| return sz; |
| } |
| pr_debug("map '%s': found key [%u], sz = %lld.\n", |
| map_name, t->type, sz); |
| if (map->def.key_size && map->def.key_size != sz) { |
| pr_warning("map '%s': conflicting key size %u != %lld.\n", |
| map_name, map->def.key_size, sz); |
| return -EINVAL; |
| } |
| map->def.key_size = sz; |
| map->btf_key_type_id = t->type; |
| } else if (strcmp(name, "value_size") == 0) { |
| __u32 sz; |
| |
| if (!get_map_field_int(map_name, obj->btf, def, m, |
| &sz)) |
| return -EINVAL; |
| pr_debug("map '%s': found value_size = %u.\n", |
| map_name, sz); |
| if (map->def.value_size && map->def.value_size != sz) { |
| pr_warning("map '%s': conflicting value size %u != %u.\n", |
| map_name, map->def.value_size, sz); |
| return -EINVAL; |
| } |
| map->def.value_size = sz; |
| } else if (strcmp(name, "value") == 0) { |
| __s64 sz; |
| |
| t = btf__type_by_id(obj->btf, m->type); |
| if (!t) { |
| pr_warning("map '%s': value type [%d] not found.\n", |
| map_name, m->type); |
| return -EINVAL; |
| } |
| if (BTF_INFO_KIND(t->info) != BTF_KIND_PTR) { |
| pr_warning("map '%s': value spec is not PTR: %u.\n", |
| map_name, BTF_INFO_KIND(t->info)); |
| return -EINVAL; |
| } |
| sz = btf__resolve_size(obj->btf, t->type); |
| if (sz < 0) { |
| pr_warning("map '%s': can't determine value size for type [%u]: %lld.\n", |
| map_name, t->type, sz); |
| return sz; |
| } |
| pr_debug("map '%s': found value [%u], sz = %lld.\n", |
| map_name, t->type, sz); |
| if (map->def.value_size && map->def.value_size != sz) { |
| pr_warning("map '%s': conflicting value size %u != %lld.\n", |
| map_name, map->def.value_size, sz); |
| return -EINVAL; |
| } |
| map->def.value_size = sz; |
| map->btf_value_type_id = t->type; |
| } else { |
| if (strict) { |
| pr_warning("map '%s': unknown field '%s'.\n", |
| map_name, name); |
| return -ENOTSUP; |
| } |
| pr_debug("map '%s': ignoring unknown field '%s'.\n", |
| map_name, name); |
| } |
| } |
| |
| if (map->def.type == BPF_MAP_TYPE_UNSPEC) { |
| pr_warning("map '%s': map type isn't specified.\n", map_name); |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict) |
| { |
| const struct btf_type *sec = NULL; |
| int nr_types, i, vlen, err; |
| const struct btf_type *t; |
| const char *name; |
| Elf_Data *data; |
| Elf_Scn *scn; |
| |
| if (obj->efile.btf_maps_shndx < 0) |
| return 0; |
| |
| scn = elf_getscn(obj->efile.elf, obj->efile.btf_maps_shndx); |
| if (scn) |
| data = elf_getdata(scn, NULL); |
| if (!scn || !data) { |
| pr_warning("failed to get Elf_Data from map section %d (%s)\n", |
| obj->efile.maps_shndx, MAPS_ELF_SEC); |
| return -EINVAL; |
| } |
| |
| nr_types = btf__get_nr_types(obj->btf); |
| for (i = 1; i <= nr_types; i++) { |
| t = btf__type_by_id(obj->btf, i); |
| if (BTF_INFO_KIND(t->info) != BTF_KIND_DATASEC) |
| continue; |
| name = btf__name_by_offset(obj->btf, t->name_off); |
| if (strcmp(name, MAPS_ELF_SEC) == 0) { |
| sec = t; |
| break; |
| } |
| } |
| |
| if (!sec) { |
| pr_warning("DATASEC '%s' not found.\n", MAPS_ELF_SEC); |
| return -ENOENT; |
| } |
| |
| vlen = BTF_INFO_VLEN(sec->info); |
| for (i = 0; i < vlen; i++) { |
| err = bpf_object__init_user_btf_map(obj, sec, i, |
| obj->efile.btf_maps_shndx, |
| data, strict); |
| if (err) |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| static int bpf_object__init_maps(struct bpf_object *obj, int flags) |
| { |
| bool strict = !(flags & MAPS_RELAX_COMPAT); |
| int err; |
| |
| err = bpf_object__init_user_maps(obj, strict); |
| if (err) |
| return err; |
| |
| err = bpf_object__init_user_btf_maps(obj, strict); |
| if (err) |
| return err; |
| |
| err = bpf_object__init_global_data_maps(obj); |
| if (err) |
| return err; |
| |
| if (obj->nr_maps) { |
| qsort(obj->maps, obj->nr_maps, sizeof(obj->maps[0]), |
| compare_bpf_map); |
| } |
| return 0; |
| } |
| |
| static bool section_have_execinstr(struct bpf_object *obj, int idx) |
| { |
| Elf_Scn *scn; |
| GElf_Shdr sh; |
| |
| scn = elf_getscn(obj->efile.elf, idx); |
| if (!scn) |
| return false; |
| |
| if (gelf_getshdr(scn, &sh) != &sh) |
| return false; |
| |
| if (sh.sh_flags & SHF_EXECINSTR) |
| return true; |
| |
| return false; |
| } |
| |
| static void bpf_object__sanitize_btf(struct bpf_object *obj) |
| { |
| bool has_datasec = obj->caps.btf_datasec; |
| bool has_func = obj->caps.btf_func; |
| struct btf *btf = obj->btf; |
| struct btf_type *t; |
| int i, j, vlen; |
| __u16 kind; |
| |
| if (!obj->btf || (has_func && has_datasec)) |
| return; |
| |
| for (i = 1; i <= btf__get_nr_types(btf); i++) { |
| t = (struct btf_type *)btf__type_by_id(btf, i); |
| kind = BTF_INFO_KIND(t->info); |
| |
| if (!has_datasec && kind == BTF_KIND_VAR) { |
| /* replace VAR with INT */ |
| t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0); |
| /* |
| * using size = 1 is the safest choice, 4 will be too |
| * big and cause kernel BTF validation failure if |
| * original variable took less than 4 bytes |
| */ |
| t->size = 1; |
| *(int *)(t+1) = BTF_INT_ENC(0, 0, 8); |
| } else if (!has_datasec && kind == BTF_KIND_DATASEC) { |
| /* replace DATASEC with STRUCT */ |
| struct btf_var_secinfo *v = (void *)(t + 1); |
| struct btf_member *m = (void *)(t + 1); |
| struct btf_type *vt; |
| char *name; |
| |
| name = (char *)btf__name_by_offset(btf, t->name_off); |
| while (*name) { |
| if (*name == '.') |
| *name = '_'; |
| name++; |
| } |
| |
| vlen = BTF_INFO_VLEN(t->info); |
| t->info = BTF_INFO_ENC(BTF_KIND_STRUCT, 0, vlen); |
| for (j = 0; j < vlen; j++, v++, m++) { |
| /* order of field assignments is important */ |
| m->offset = v->offset * 8; |
| m->type = v->type; |
| /* preserve variable name as member name */ |
| vt = (void *)btf__type_by_id(btf, v->type); |
| m->name_off = vt->name_off; |
| } |
| } else if (!has_func && kind == BTF_KIND_FUNC_PROTO) { |
| /* replace FUNC_PROTO with ENUM */ |
| vlen = BTF_INFO_VLEN(t->info); |
| t->info = BTF_INFO_ENC(BTF_KIND_ENUM, 0, vlen); |
| t->size = sizeof(__u32); /* kernel enforced */ |
| } else if (!has_func && kind == BTF_KIND_FUNC) { |
| /* replace FUNC with TYPEDEF */ |
| t->info = BTF_INFO_ENC(BTF_KIND_TYPEDEF, 0, 0); |
| } |
| } |
| } |
| |
| static void bpf_object__sanitize_btf_ext(struct bpf_object *obj) |
| { |
| if (!obj->btf_ext) |
| return; |
| |
| if (!obj->caps.btf_func) { |
| btf_ext__free(obj->btf_ext); |
| obj->btf_ext = NULL; |
| } |
| } |
| |
| static bool bpf_object__is_btf_mandatory(const struct bpf_object *obj) |
| { |
| return obj->efile.btf_maps_shndx >= 0; |
| } |
| |
| static int bpf_object__init_btf(struct bpf_object *obj, |
| Elf_Data *btf_data, |
| Elf_Data *btf_ext_data) |
| { |
| bool btf_required = bpf_object__is_btf_mandatory(obj); |
| int err = 0; |
| |
| if (btf_data) { |
| obj->btf = btf__new(btf_data->d_buf, btf_data->d_size); |
| if (IS_ERR(obj->btf)) { |
| pr_warning("Error loading ELF section %s: %d.\n", |
| BTF_ELF_SEC, err); |
| goto out; |
| } |
| err = btf__finalize_data(obj, obj->btf); |
| if (err) { |
| pr_warning("Error finalizing %s: %d.\n", |
| BTF_ELF_SEC, err); |
| goto out; |
| } |
| } |
| if (btf_ext_data) { |
| if (!obj->btf) { |
| pr_debug("Ignore ELF section %s because its depending ELF section %s is not found.\n", |
| BTF_EXT_ELF_SEC, BTF_ELF_SEC); |
| goto out; |
| } |
| obj->btf_ext = btf_ext__new(btf_ext_data->d_buf, |
| btf_ext_data->d_size); |
| if (IS_ERR(obj->btf_ext)) { |
| pr_warning("Error loading ELF section %s: %ld. Ignored and continue.\n", |
| BTF_EXT_ELF_SEC, PTR_ERR(obj->btf_ext)); |
| obj->btf_ext = NULL; |
| goto out; |
| } |
| } |
| out: |
| if (err || IS_ERR(obj->btf)) { |
| if (btf_required) |
| err = err ? : PTR_ERR(obj->btf); |
| else |
| err = 0; |
| if (!IS_ERR_OR_NULL(obj->btf)) |
| btf__free(obj->btf); |
| obj->btf = NULL; |
| } |
| if (btf_required && !obj->btf) { |
| pr_warning("BTF is required, but is missing or corrupted.\n"); |
| return err == 0 ? -ENOENT : err; |
| } |
| return 0; |
| } |
| |
| static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj) |
| { |
| int err = 0; |
| |
| if (!obj->btf) |
| return 0; |
| |
| bpf_object__sanitize_btf(obj); |
| bpf_object__sanitize_btf_ext(obj); |
| |
| err = btf__load(obj->btf); |
| if (err) { |
| pr_warning("Error loading %s into kernel: %d.\n", |
| BTF_ELF_SEC, err); |
| btf__free(obj->btf); |
| obj->btf = NULL; |
| /* btf_ext can't exist without btf, so free it as well */ |
| if (obj->btf_ext) { |
| btf_ext__free(obj->btf_ext); |
| obj->btf_ext = NULL; |
| } |
| |
| if (bpf_object__is_btf_mandatory(obj)) |
| return err; |
| } |
| return 0; |
| } |
| |
| static int bpf_object__elf_collect(struct bpf_object *obj, int flags) |
| { |
| Elf *elf = obj->efile.elf; |
| GElf_Ehdr *ep = &obj->efile.ehdr; |
| Elf_Data *btf_ext_data = NULL; |
| Elf_Data *btf_data = NULL; |
| 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(%d) header from %s\n", |
| idx, obj->path); |
| return -LIBBPF_ERRNO__FORMAT; |
| } |
| |
| name = elf_strptr(elf, ep->e_shstrndx, sh.sh_name); |
| if (!name) { |
| pr_warning("failed to get section(%d) name from %s\n", |
| idx, obj->path); |
| return -LIBBPF_ERRNO__FORMAT; |
| } |
| |
| data = elf_getdata(scn, 0); |
| if (!data) { |
| pr_warning("failed to get section(%d) data from %s(%s)\n", |
| idx, name, obj->path); |
| return -LIBBPF_ERRNO__FORMAT; |
| } |
| pr_debug("section(%d) %s, size %ld, link %d, flags %lx, type=%d\n", |
| idx, 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); |
| if (err) |
| return err; |
| } else if (strcmp(name, "version") == 0) { |
| err = bpf_object__init_kversion(obj, |
| data->d_buf, |
| data->d_size); |
| if (err) |
| return err; |
| } else if (strcmp(name, "maps") == 0) { |
| obj->efile.maps_shndx = idx; |
| } else if (strcmp(name, MAPS_ELF_SEC) == 0) { |
| obj->efile.btf_maps_shndx = idx; |
| } else if (strcmp(name, BTF_ELF_SEC) == 0) { |
| btf_data = data; |
| } else if (strcmp(name, BTF_EXT_ELF_SEC) == 0) { |
| btf_ext_data = data; |
| } else if (sh.sh_type == SHT_SYMTAB) { |
| if (obj->efile.symbols) { |
| pr_warning("bpf: multiple SYMTAB in %s\n", |
| obj->path); |
| return -LIBBPF_ERRNO__FORMAT; |
| } |
| obj->efile.symbols = data; |
| obj->efile.strtabidx = sh.sh_link; |
| } else if (sh.sh_type == SHT_PROGBITS && data->d_size > 0) { |
| if (sh.sh_flags & SHF_EXECINSTR) { |
| if (strcmp(name, ".text") == 0) |
| obj->efile.text_shndx = idx; |
| err = bpf_object__add_program(obj, data->d_buf, |
| data->d_size, name, idx); |
| if (err) { |
| char errmsg[STRERR_BUFSIZE]; |
| char *cp = libbpf_strerror_r(-err, errmsg, |
| sizeof(errmsg)); |
| |
| pr_warning("failed to alloc program %s (%s): %s", |
| name, obj->path, cp); |
| return err; |
| } |
| } else if (strcmp(name, ".data") == 0) { |
| obj->efile.data = data; |
| obj->efile.data_shndx = idx; |
| } else if (strcmp(name, ".rodata") == 0) { |
| obj->efile.rodata = data; |
| obj->efile.rodata_shndx = idx; |
| } else { |
| pr_debug("skip section(%d) %s\n", idx, name); |
| } |
| } else if (sh.sh_type == SHT_REL) { |
| int nr_reloc = obj->efile.nr_reloc; |
| void *reloc = obj->efile.reloc; |
| int sec = sh.sh_info; /* points to other section */ |
| |
| /* Only do relo for section with exec instructions */ |
| if (!section_have_execinstr(obj, sec)) { |
| pr_debug("skip relo %s(%d) for section(%d)\n", |
| name, idx, sec); |
| continue; |
| } |
| |
| reloc = reallocarray(reloc, nr_reloc + 1, |
| sizeof(*obj->efile.reloc)); |
| if (!reloc) { |
| pr_warning("realloc failed\n"); |
| return -ENOMEM; |
| } |
| |
| obj->efile.reloc = reloc; |
| obj->efile.nr_reloc++; |
| |
| obj->efile.reloc[nr_reloc].shdr = sh; |
| obj->efile.reloc[nr_reloc].data = data; |
| } else if (sh.sh_type == SHT_NOBITS && strcmp(name, ".bss") == 0) { |
| obj->efile.bss = data; |
| obj->efile.bss_shndx = idx; |
| } else { |
| pr_debug("skip section(%d) %s\n", idx, name); |
| } |
| } |
| |
| if (!obj->efile.strtabidx || obj->efile.strtabidx >= idx) { |
| pr_warning("Corrupted ELF file: index of strtab invalid\n"); |
| return -LIBBPF_ERRNO__FORMAT; |
| } |
| err = bpf_object__init_btf(obj, btf_data, btf_ext_data); |
| if (!err) |
| err = bpf_object__init_maps(obj, flags); |
| if (!err) |
| err = bpf_object__sanitize_and_load_btf(obj); |
| if (!err) |
| err = bpf_object__init_prog_names(obj); |
| 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; |
| } |
| |
| struct bpf_program * |
| bpf_object__find_program_by_title(const struct bpf_object *obj, |
| const char *title) |
| { |
| struct bpf_program *pos; |
| |
| bpf_object__for_each_program(pos, obj) { |
| if (pos->section_name && !strcmp(pos->section_name, title)) |
| return pos; |
| } |
| return NULL; |
| } |
| |
| static bool bpf_object__shndx_is_data(const struct bpf_object *obj, |
| int shndx) |
| { |
| return shndx == obj->efile.data_shndx || |
| shndx == obj->efile.bss_shndx || |
| shndx == obj->efile.rodata_shndx; |
| } |
| |
| static bool bpf_object__shndx_is_maps(const struct bpf_object *obj, |
| int shndx) |
| { |
| return shndx == obj->efile.maps_shndx || |
| shndx == obj->efile.btf_maps_shndx; |
| } |
| |
| static bool bpf_object__relo_in_known_section(const struct bpf_object *obj, |
| int shndx) |
| { |
| return shndx == obj->efile.text_shndx || |
| bpf_object__shndx_is_maps(obj, shndx) || |
| bpf_object__shndx_is_data(obj, shndx); |
| } |
| |
| static enum libbpf_map_type |
| bpf_object__section_to_libbpf_map_type(const struct bpf_object *obj, int shndx) |
| { |
| if (shndx == obj->efile.data_shndx) |
| return LIBBPF_MAP_DATA; |
| else if (shndx == obj->efile.bss_shndx) |
| return LIBBPF_MAP_BSS; |
| else if (shndx == obj->efile.rodata_shndx) |
| return LIBBPF_MAP_RODATA; |
| else |
| return LIBBPF_MAP_UNSPEC; |
| } |
| |
| static int |
| bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr, |
| Elf_Data *data, struct bpf_object *obj) |
| { |
| Elf_Data *symbols = obj->efile.symbols; |
| struct bpf_map *maps = obj->maps; |
| size_t nr_maps = obj->nr_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++) { |
| struct bpf_insn *insns = prog->insns; |
| enum libbpf_map_type type; |
| unsigned int insn_idx; |
| unsigned int shdr_idx; |
| const char *name; |
| size_t map_idx; |
| GElf_Sym sym; |
| GElf_Rel rel; |
| |
| 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; |
| } |
| |
| name = elf_strptr(obj->efile.elf, obj->efile.strtabidx, |
| sym.st_name) ? : "<?>"; |
| |
| pr_debug("relo for %lld value %lld name %d (\'%s\')\n", |
| (long long) (rel.r_info >> 32), |
| (long long) sym.st_value, sym.st_name, name); |
| |
| shdr_idx = sym.st_shndx; |
| if (!bpf_object__relo_in_known_section(obj, shdr_idx)) { |
| pr_warning("Program '%s' contains unrecognized relo data pointing to section %u\n", |
| prog->section_name, shdr_idx); |
| 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_JMP | BPF_CALL)) { |
| if (insns[insn_idx].src_reg != BPF_PSEUDO_CALL) { |
| pr_warning("incorrect bpf_call opcode\n"); |
| return -LIBBPF_ERRNO__RELOC; |
| } |
| prog->reloc_desc[i].type = RELO_CALL; |
| prog->reloc_desc[i].insn_idx = insn_idx; |
| prog->reloc_desc[i].text_off = sym.st_value; |
| obj->has_pseudo_calls = true; |
| continue; |
| } |
| |
| 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; |
| } |
| |
| if (bpf_object__shndx_is_maps(obj, shdr_idx) || |
| bpf_object__shndx_is_data(obj, shdr_idx)) { |
| type = bpf_object__section_to_libbpf_map_type(obj, shdr_idx); |
| if (type != LIBBPF_MAP_UNSPEC) { |
| if (GELF_ST_BIND(sym.st_info) == STB_GLOBAL) { |
| pr_warning("bpf: relocation: not yet supported relo for non-static global \'%s\' variable found in insns[%d].code 0x%x\n", |
| name, insn_idx, insns[insn_idx].code); |
| return -LIBBPF_ERRNO__RELOC; |
| } |
| if (!obj->caps.global_data) { |
| pr_warning("bpf: relocation: kernel does not support global \'%s\' variable access in insns[%d]\n", |
| name, insn_idx); |
| return -LIBBPF_ERRNO__RELOC; |
| } |
| } |
| |
| for (map_idx = 0; map_idx < nr_maps; map_idx++) { |
| if (maps[map_idx].libbpf_type != type) |
| continue; |
| if (type != LIBBPF_MAP_UNSPEC || |
| (maps[map_idx].sec_idx == sym.st_shndx && |
| maps[map_idx].sec_offset == sym.st_value)) { |
| pr_debug("relocation: found map %zd (%s, sec_idx %d, offset %zu) for insn %u\n", |
| map_idx, maps[map_idx].name, |
| maps[map_idx].sec_idx, |
| maps[map_idx].sec_offset, |
| insn_idx); |
| break; |
| } |
| } |
| |
| if (map_idx >= nr_maps) { |
| pr_warning("bpf relocation: map_idx %d larger than %d\n", |
| (int)map_idx, (int)nr_maps - 1); |
| return -LIBBPF_ERRNO__RELOC; |
| } |
| |
| prog->reloc_desc[i].type = type != LIBBPF_MAP_UNSPEC ? |
| RELO_DATA : RELO_LD64; |
| prog->reloc_desc[i].insn_idx = insn_idx; |
| prog->reloc_desc[i].map_idx = map_idx; |
| } |
| } |
| return 0; |
| } |
| |
| static int bpf_map_find_btf_info(struct bpf_object *obj, struct bpf_map *map) |
| { |
| struct bpf_map_def *def = &map->def; |
| __u32 key_type_id = 0, value_type_id = 0; |
| int ret; |
| |
| /* if it's BTF-defined map, we don't need to search for type IDs */ |
| if (map->sec_idx == obj->efile.btf_maps_shndx) |
| return 0; |
| |
| if (!bpf_map__is_internal(map)) { |
| ret = btf__get_map_kv_tids(obj->btf, map->name, def->key_size, |
| def->value_size, &key_type_id, |
| &value_type_id); |
| } else { |
| /* |
| * LLVM annotates global data differently in BTF, that is, |
| * only as '.data', '.bss' or '.rodata'. |
| */ |
| ret = btf__find_by_name(obj->btf, |
| libbpf_type_to_btf_name[map->libbpf_type]); |
| } |
| if (ret < 0) |
| return ret; |
| |
| map->btf_key_type_id = key_type_id; |
| map->btf_value_type_id = bpf_map__is_internal(map) ? |
| ret : value_type_id; |
| return 0; |
| } |
| |
| int bpf_map__reuse_fd(struct bpf_map *map, int fd) |
| { |
| struct bpf_map_info info = {}; |
| __u32 len = sizeof(info); |
| int new_fd, err; |
| char *new_name; |
| |
| err = bpf_obj_get_info_by_fd(fd, &info, &len); |
| if (err) |
| return err; |
| |
| new_name = strdup(info.name); |
| if (!new_name) |
| return -errno; |
| |
| new_fd = open("/", O_RDONLY | O_CLOEXEC); |
| if (new_fd < 0) |
| goto err_free_new_name; |
| |
| new_fd = dup3(fd, new_fd, O_CLOEXEC); |
| if (new_fd < 0) |
| goto err_close_new_fd; |
| |
| err = zclose(map->fd); |
| if (err) |
| goto err_close_new_fd; |
| free(map->name); |
| |
| map->fd = new_fd; |
| map->name = new_name; |
| map->def.type = info.type; |
| map->def.key_size = info.key_size; |
| map->def.value_size = info.value_size; |
| map->def.max_entries = info.max_entries; |
| map->def.map_flags = info.map_flags; |
| map->btf_key_type_id = info.btf_key_type_id; |
| map->btf_value_type_id = info.btf_value_type_id; |
| |
| return 0; |
| |
| err_close_new_fd: |
| close(new_fd); |
| err_free_new_name: |
| free(new_name); |
| return -errno; |
| } |
| |
| int bpf_map__resize(struct bpf_map *map, __u32 max_entries) |
| { |
| if (!map || !max_entries) |
| return -EINVAL; |
| |
| /* If map already created, its attributes can't be changed. */ |
| if (map->fd >= 0) |
| return -EBUSY; |
| |
| map->def.max_entries = max_entries; |
| |
| return 0; |
| } |
| |
| static int |
| bpf_object__probe_name(struct bpf_object *obj) |
| { |
| struct bpf_load_program_attr attr; |
| char *cp, errmsg[STRERR_BUFSIZE]; |
| struct bpf_insn insns[] = { |
| BPF_MOV64_IMM(BPF_REG_0, 0), |
| BPF_EXIT_INSN(), |
| }; |
| int ret; |
| |
| /* make sure basic loading works */ |
| |
| memset(&attr, 0, sizeof(attr)); |
| attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; |
| attr.insns = insns; |
| attr.insns_cnt = ARRAY_SIZE(insns); |
| attr.license = "GPL"; |
| |
| ret = bpf_load_program_xattr(&attr, NULL, 0); |
| if (ret < 0) { |
| cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
| pr_warning("Error in %s():%s(%d). Couldn't load basic 'r0 = 0' BPF program.\n", |
| __func__, cp, errno); |
| return -errno; |
| } |
| close(ret); |
| |
| /* now try the same program, but with the name */ |
| |
| attr.name = "test"; |
| ret = bpf_load_program_xattr(&attr, NULL, 0); |
| if (ret >= 0) { |
| obj->caps.name = 1; |
| close(ret); |
| } |
| |
| return 0; |
| } |
| |
| static int |
| bpf_object__probe_global_data(struct bpf_object *obj) |
| { |
| struct bpf_load_program_attr prg_attr; |
| struct bpf_create_map_attr map_attr; |
| char *cp, errmsg[STRERR_BUFSIZE]; |
| struct bpf_insn insns[] = { |
| BPF_LD_MAP_VALUE(BPF_REG_1, 0, 16), |
| BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 42), |
| BPF_MOV64_IMM(BPF_REG_0, 0), |
| BPF_EXIT_INSN(), |
| }; |
| int ret, map; |
| |
| memset(&map_attr, 0, sizeof(map_attr)); |
| map_attr.map_type = BPF_MAP_TYPE_ARRAY; |
| map_attr.key_size = sizeof(int); |
| map_attr.value_size = 32; |
| map_attr.max_entries = 1; |
| |
| map = bpf_create_map_xattr(&map_attr); |
| if (map < 0) { |
| cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
| pr_warning("Error in %s():%s(%d). Couldn't create simple array map.\n", |
| __func__, cp, errno); |
| return -errno; |
| } |
| |
| insns[0].imm = map; |
| |
| memset(&prg_attr, 0, sizeof(prg_attr)); |
| prg_attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; |
| prg_attr.insns = insns; |
| prg_attr.insns_cnt = ARRAY_SIZE(insns); |
| prg_attr.license = "GPL"; |
| |
| ret = bpf_load_program_xattr(&prg_attr, NULL, 0); |
| if (ret >= 0) { |
| obj->caps.global_data = 1; |
| close(ret); |
| } |
| |
| close(map); |
| return 0; |
| } |
| |
| static int bpf_object__probe_btf_func(struct bpf_object *obj) |
| { |
| const char strs[] = "\0int\0x\0a"; |
| /* void x(int a) {} */ |
| __u32 types[] = { |
| /* int */ |
| BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ |
| /* FUNC_PROTO */ /* [2] */ |
| BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), |
| BTF_PARAM_ENC(7, 1), |
| /* FUNC x */ /* [3] */ |
| BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0), 2), |
| }; |
| int btf_fd; |
| |
| btf_fd = libbpf__load_raw_btf((char *)types, sizeof(types), |
| strs, sizeof(strs)); |
| if (btf_fd >= 0) { |
| obj->caps.btf_func = 1; |
| close(btf_fd); |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| static int bpf_object__probe_btf_datasec(struct bpf_object *obj) |
| { |
| const char strs[] = "\0x\0.data"; |
| /* static int a; */ |
| __u32 types[] = { |
| /* int */ |
| BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ |
| /* VAR x */ /* [2] */ |
| BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1), |
| BTF_VAR_STATIC, |
| /* DATASEC val */ /* [3] */ |
| BTF_TYPE_ENC(3, BTF_INFO_ENC(BTF_KIND_DATASEC, 0, 1), 4), |
| BTF_VAR_SECINFO_ENC(2, 0, 4), |
| }; |
| int btf_fd; |
| |
| btf_fd = libbpf__load_raw_btf((char *)types, sizeof(types), |
| strs, sizeof(strs)); |
| if (btf_fd >= 0) { |
| obj->caps.btf_datasec = 1; |
| close(btf_fd); |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| static int |
| bpf_object__probe_caps(struct bpf_object *obj) |
| { |
| int (*probe_fn[])(struct bpf_object *obj) = { |
| bpf_object__probe_name, |
| bpf_object__probe_global_data, |
| bpf_object__probe_btf_func, |
| bpf_object__probe_btf_datasec, |
| }; |
| int i, ret; |
| |
| for (i = 0; i < ARRAY_SIZE(probe_fn); i++) { |
| ret = probe_fn[i](obj); |
| if (ret < 0) |
| pr_debug("Probe #%d failed with %d.\n", i, ret); |
| } |
| |
| return 0; |
| } |
| |
| static int |
| bpf_object__populate_internal_map(struct bpf_object *obj, struct bpf_map *map) |
| { |
| char *cp, errmsg[STRERR_BUFSIZE]; |
| int err, zero = 0; |
| __u8 *data; |
| |
| /* Nothing to do here since kernel already zero-initializes .bss map. */ |
| if (map->libbpf_type == LIBBPF_MAP_BSS) |
| return 0; |
| |
| data = map->libbpf_type == LIBBPF_MAP_DATA ? |
| obj->sections.data : obj->sections.rodata; |
| |
| err = bpf_map_update_elem(map->fd, &zero, data, 0); |
| /* Freeze .rodata map as read-only from syscall side. */ |
| if (!err && map->libbpf_type == LIBBPF_MAP_RODATA) { |
| err = bpf_map_freeze(map->fd); |
| if (err) { |
| cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
| pr_warning("Error freezing map(%s) as read-only: %s\n", |
| map->name, cp); |
| err = 0; |
| } |
| } |
| return err; |
| } |
| |
| static int |
| bpf_object__create_maps(struct bpf_object *obj) |
| { |
| struct bpf_create_map_attr create_attr = {}; |
| int nr_cpus = 0; |
| unsigned int i; |
| int err; |
| |
| for (i = 0; i < obj->nr_maps; i++) { |
| struct bpf_map *map = &obj->maps[i]; |
| struct bpf_map_def *def = &map->def; |
| char *cp, errmsg[STRERR_BUFSIZE]; |
| int *pfd = &map->fd; |
| |
| if (map->fd >= 0) { |
| pr_debug("skip map create (preset) %s: fd=%d\n", |
| map->name, map->fd); |
| continue; |
| } |
| |
| if (obj->caps.name) |
| create_attr.name = map->name; |
| create_attr.map_ifindex = map->map_ifindex; |
| create_attr.map_type = def->type; |
| create_attr.map_flags = def->map_flags; |
| create_attr.key_size = def->key_size; |
| create_attr.value_size = def->value_size; |
| if (def->type == BPF_MAP_TYPE_PERF_EVENT_ARRAY && |
| !def->max_entries) { |
| if (!nr_cpus) |
| nr_cpus = libbpf_num_possible_cpus(); |
| if (nr_cpus < 0) { |
| pr_warning("failed to determine number of system CPUs: %d\n", |
| nr_cpus); |
| err = nr_cpus; |
| goto err_out; |
| } |
| pr_debug("map '%s': setting size to %d\n", |
| map->name, nr_cpus); |
| create_attr.max_entries = nr_cpus; |
| } else { |
| create_attr.max_entries = def->max_entries; |
| } |
| create_attr.btf_fd = 0; |
| create_attr.btf_key_type_id = 0; |
| create_attr.btf_value_type_id = 0; |
| if (bpf_map_type__is_map_in_map(def->type) && |
| map->inner_map_fd >= 0) |
| create_attr.inner_map_fd = map->inner_map_fd; |
| |
| if (obj->btf && !bpf_map_find_btf_info(obj, map)) { |
| create_attr.btf_fd = btf__fd(obj->btf); |
| create_attr.btf_key_type_id = map->btf_key_type_id; |
| create_attr.btf_value_type_id = map->btf_value_type_id; |
| } |
| |
| *pfd = bpf_create_map_xattr(&create_attr); |
| if (*pfd < 0 && (create_attr.btf_key_type_id || |
| create_attr.btf_value_type_id)) { |
| err = -errno; |
| cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); |
| pr_warning("Error in bpf_create_map_xattr(%s):%s(%d). Retrying without BTF.\n", |
| map->name, cp, err); |
| create_attr.btf_fd = 0; |
| create_attr.btf_key_type_id = 0; |
| create_attr.btf_value_type_id = 0; |
| map->btf_key_type_id = 0; |
| map->btf_value_type_id = 0; |
| *pfd = bpf_create_map_xattr(&create_attr); |
| } |
| |
| if (*pfd < 0) { |
| size_t j; |
| |
| err = -errno; |
| err_out: |
| cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); |
| pr_warning("failed to create map (name: '%s'): %s(%d)\n", |
| map->name, cp, err); |
| for (j = 0; j < i; j++) |
| zclose(obj->maps[j].fd); |
| return err; |
| } |
| |
| if (bpf_map__is_internal(map)) { |
| err = bpf_object__populate_internal_map(obj, map); |
| if (err < 0) { |
| zclose(*pfd); |
| goto err_out; |
| } |
| } |
| |
| pr_debug("created map %s: fd=%d\n", map->name, *pfd); |
| } |
| |
| return 0; |
| } |
| |
| static int |
| check_btf_ext_reloc_err(struct bpf_program *prog, int err, |
| void *btf_prog_info, const char *info_name) |
| { |
| if (err != -ENOENT) { |
| pr_warning("Error in loading %s for sec %s.\n", |
| info_name, prog->section_name); |
| return err; |
| } |
| |
| /* err == -ENOENT (i.e. prog->section_name not found in btf_ext) */ |
| |
| if (btf_prog_info) { |
| /* |
| * Some info has already been found but has problem |
| * in the last btf_ext reloc. Must have to error out. |
| */ |
| pr_warning("Error in relocating %s for sec %s.\n", |
| info_name, prog->section_name); |
| return err; |
| } |
| |
| /* Have problem loading the very first info. Ignore the rest. */ |
| pr_warning("Cannot find %s for main program sec %s. Ignore all %s.\n", |
| info_name, prog->section_name, info_name); |
| return 0; |
| } |
| |
| static int |
| bpf_program_reloc_btf_ext(struct bpf_program *prog, struct bpf_object *obj, |
| const char *section_name, __u32 insn_offset) |
| { |
| int err; |
| |
| if (!insn_offset || prog->func_info) { |
| /* |
| * !insn_offset => main program |
| * |
| * For sub prog, the main program's func_info has to |
| * be loaded first (i.e. prog->func_info != NULL) |
| */ |
| err = btf_ext__reloc_func_info(obj->btf, obj->btf_ext, |
| section_name, insn_offset, |
| &prog->func_info, |
| &prog->func_info_cnt); |
| if (err) |
| return check_btf_ext_reloc_err(prog, err, |
| prog->func_info, |
| "bpf_func_info"); |
| |
| prog->func_info_rec_size = btf_ext__func_info_rec_size(obj->btf_ext); |
| } |
| |
| if (!insn_offset || prog->line_info) { |
| err = btf_ext__reloc_line_info(obj->btf, obj->btf_ext, |
| section_name, insn_offset, |
| &prog->line_info, |
| &prog->line_info_cnt); |
| if (err) |
| return check_btf_ext_reloc_err(prog, err, |
| prog->line_info, |
| "bpf_line_info"); |
| |
| prog->line_info_rec_size = btf_ext__line_info_rec_size(obj->btf_ext); |
| } |
| |
| return 0; |
| } |
| |
| static int |
| bpf_program__reloc_text(struct bpf_program *prog, struct bpf_object *obj, |
| struct reloc_desc *relo) |
| { |
| struct bpf_insn *insn, *new_insn; |
| struct bpf_program *text; |
| size_t new_cnt; |
| int err; |
| |
| if (relo->type != RELO_CALL) |
| return -LIBBPF_ERRNO__RELOC; |
| |
| if (prog->idx == obj->efile.text_shndx) { |
| pr_warning("relo in .text insn %d into off %d\n", |
| relo->insn_idx, relo->text_off); |
| return -LIBBPF_ERRNO__RELOC; |
| } |
| |
| if (prog->main_prog_cnt == 0) { |
| text = bpf_object__find_prog_by_idx(obj, obj->efile.text_shndx); |
| if (!text) { |
| pr_warning("no .text section found yet relo into text exist\n"); |
| return -LIBBPF_ERRNO__RELOC; |
| } |
| new_cnt = prog->insns_cnt + text->insns_cnt; |
| new_insn = reallocarray(prog->insns, new_cnt, sizeof(*insn)); |
| if (!new_insn) { |
| pr_warning("oom in prog realloc\n"); |
| return -ENOMEM; |
| } |
| |
| if (obj->btf_ext) { |
| err = bpf_program_reloc_btf_ext(prog, obj, |
| text->section_name, |
| prog->insns_cnt); |
| if (err) |
| return err; |
| } |
| |
| memcpy(new_insn + prog->insns_cnt, text->insns, |
| text->insns_cnt * sizeof(*insn)); |
| prog->insns = new_insn; |
| prog->main_prog_cnt = prog->insns_cnt; |
| prog->insns_cnt = new_cnt; |
| pr_debug("added %zd insn from %s to prog %s\n", |
| text->insns_cnt, text->section_name, |
| prog->section_name); |
| } |
| insn = &prog->insns[relo->insn_idx]; |
| insn->imm += prog->main_prog_cnt - relo->insn_idx; |
| return 0; |
| } |
| |
| static int |
| bpf_program__relocate(struct bpf_program *prog, struct bpf_object *obj) |
| { |
| int i, err; |
| |
| if (!prog) |
| return 0; |
| |
| if (obj->btf_ext) { |
| err = bpf_program_reloc_btf_ext(prog, obj, |
| prog->section_name, 0); |
| if (err) |
| return err; |
| } |
| |
| if (!prog->reloc_desc) |
| return 0; |
| |
| for (i = 0; i < prog->nr_reloc; i++) { |
| if (prog->reloc_desc[i].type == RELO_LD64 || |
| prog->reloc_desc[i].type == RELO_DATA) { |
| bool relo_data = prog->reloc_desc[i].type == RELO_DATA; |
| struct bpf_insn *insns = prog->insns; |
| int insn_idx, map_idx; |
| |
| insn_idx = prog->reloc_desc[i].insn_idx; |
| map_idx = prog->reloc_desc[i].map_idx; |
| |
| if (insn_idx + 1 >= (int)prog->insns_cnt) { |
| pr_warning("relocation out of range: '%s'\n", |
| prog->section_name); |
| return -LIBBPF_ERRNO__RELOC; |
| } |
| |
| if (!relo_data) { |
| insns[insn_idx].src_reg = BPF_PSEUDO_MAP_FD; |
| } else { |
| insns[insn_idx].src_reg = BPF_PSEUDO_MAP_VALUE; |
| insns[insn_idx + 1].imm = insns[insn_idx].imm; |
| } |
| insns[insn_idx].imm = obj->maps[map_idx].fd; |
| } else if (prog->reloc_desc[i].type == RELO_CALL) { |
| err = bpf_program__reloc_text(prog, obj, |
| &prog->reloc_desc[i]); |
| if (err) |
| return err; |
| } |
| } |
| |
| 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; |
| |
| 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 section(%d)\n", idx); |
| return -LIBBPF_ERRNO__RELOC; |
| } |
| |
| err = bpf_program__collect_reloc(prog, shdr, data, obj); |
| if (err) |
| return err; |
| } |
| return 0; |
| } |
| |
| static int |
| load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, |
| char *license, __u32 kern_version, int *pfd) |
| { |
| struct bpf_load_program_attr load_attr; |
| char *cp, errmsg[STRERR_BUFSIZE]; |
| int log_buf_size = BPF_LOG_BUF_SIZE; |
| char *log_buf; |
| int btf_fd, ret; |
| |
| if (!insns || !insns_cnt) |
| return -EINVAL; |
| |
| memset(&load_attr, 0, sizeof(struct bpf_load_program_attr)); |
| load_attr.prog_type = prog->type; |
| load_attr.expected_attach_type = prog->expected_attach_type; |
| if (prog->caps->name) |
| load_attr.name = prog->name; |
| load_attr.insns = insns; |
| load_attr.insns_cnt = insns_cnt; |
| load_attr.license = license; |
| load_attr.kern_version = kern_version; |
| load_attr.prog_ifindex = prog->prog_ifindex; |
| /* if .BTF.ext was loaded, kernel supports associated BTF for prog */ |
| if (prog->obj->btf_ext) |
| btf_fd = bpf_object__btf_fd(prog->obj); |
| else |
| btf_fd = -1; |
| load_attr.prog_btf_fd = btf_fd >= 0 ? btf_fd : 0; |
| load_attr.func_info = prog->func_info; |
| load_attr.func_info_rec_size = prog->func_info_rec_size; |
| load_attr.func_info_cnt = prog->func_info_cnt; |
| load_attr.line_info = prog->line_info; |
| load_attr.line_info_rec_size = prog->line_info_rec_size; |
| load_attr.line_info_cnt = prog->line_info_cnt; |
| load_attr.log_level = prog->log_level; |
| load_attr.prog_flags = prog->prog_flags; |
| |
| retry_load: |
| log_buf = malloc(log_buf_size); |
| if (!log_buf) |
| pr_warning("Alloc log buffer for bpf loader error, continue without log\n"); |
| |
| ret = bpf_load_program_xattr(&load_attr, log_buf, log_buf_size); |
| |
| if (ret >= 0) { |
| if (load_attr.log_level) |
| pr_debug("verifier log:\n%s", log_buf); |
| *pfd = ret; |
| ret = 0; |
| goto out; |
| } |
| |
| if (errno == ENOSPC) { |
| log_buf_size <<= 1; |
| free(log_buf); |
| goto retry_load; |
| } |
| ret = -LIBBPF_ERRNO__LOAD; |
| cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
| pr_warning("load bpf program failed: %s\n", cp); |
| |
| 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 (load_attr.insns_cnt >= BPF_MAXINSNS) { |
| pr_warning("Program too large (%zu insns), at most %d insns\n", |
| load_attr.insns_cnt, BPF_MAXINSNS); |
| ret = -LIBBPF_ERRNO__PROG2BIG; |
| } else { |
| /* Wrong program type? */ |
| if (load_attr.prog_type != BPF_PROG_TYPE_KPROBE) { |
| int fd; |
| |
| load_attr.prog_type = BPF_PROG_TYPE_KPROBE; |
| load_attr.expected_attach_type = 0; |
| fd = bpf_load_program_xattr(&load_attr, 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; |
| } |
| |
| 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, 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; |
| |
| memset(&result, 0, 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, 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 bool bpf_program__is_function_storage(const struct bpf_program *prog, |
| const struct bpf_object *obj) |
| { |
| return prog->idx == obj->efile.text_shndx && obj->has_pseudo_calls; |
| } |
| |
| static int |
| bpf_object__load_progs(struct bpf_object *obj, int log_level) |
| { |
| size_t i; |
| int err; |
| |
| for (i = 0; i < obj->nr_programs; i++) { |
| if (bpf_program__is_function_storage(&obj->programs[i], obj)) |
| continue; |
| obj->programs[i].log_level |= log_level; |
| err = bpf_program__load(&obj->programs[i], |
| obj->license, |
| obj->kern_version); |
| if (err) |
| return err; |
| } |
| return 0; |
| } |
| |
| static bool bpf_prog_type__needs_kver(enum bpf_prog_type type) |
| { |
| switch (type) { |
| case BPF_PROG_TYPE_SOCKET_FILTER: |
| case BPF_PROG_TYPE_SCHED_CLS: |
| case BPF_PROG_TYPE_SCHED_ACT: |
| case BPF_PROG_TYPE_XDP: |
| case BPF_PROG_TYPE_CGROUP_SKB: |
| case BPF_PROG_TYPE_CGROUP_SOCK: |
| case BPF_PROG_TYPE_LWT_IN: |
| case BPF_PROG_TYPE_LWT_OUT: |
| case BPF_PROG_TYPE_LWT_XMIT: |
| case BPF_PROG_TYPE_LWT_SEG6LOCAL: |
| case BPF_PROG_TYPE_SOCK_OPS: |
| case BPF_PROG_TYPE_SK_SKB: |
| case BPF_PROG_TYPE_CGROUP_DEVICE: |
| case BPF_PROG_TYPE_SK_MSG: |
| case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: |
| case BPF_PROG_TYPE_LIRC_MODE2: |
| case BPF_PROG_TYPE_SK_REUSEPORT: |
| case BPF_PROG_TYPE_FLOW_DISSECTOR: |
| case BPF_PROG_TYPE_UNSPEC: |
| case BPF_PROG_TYPE_TRACEPOINT: |
| case BPF_PROG_TYPE_RAW_TRACEPOINT: |
| case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE: |
| case BPF_PROG_TYPE_PERF_EVENT: |
| case BPF_PROG_TYPE_CGROUP_SYSCTL: |
| case BPF_PROG_TYPE_CGROUP_SOCKOPT: |
| return false; |
| case BPF_PROG_TYPE_KPROBE: |
| default: |
| return true; |
| } |
| } |
| |
| static int bpf_object__validate(struct bpf_object *obj, bool needs_kver) |
| { |
| if (needs_kver && 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, |
| bool needs_kver, int flags) |
| { |
| 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__probe_caps(obj), err, out); |
| CHECK_ERR(bpf_object__elf_collect(obj, flags), err, out); |
| CHECK_ERR(bpf_object__collect_reloc(obj), err, out); |
| CHECK_ERR(bpf_object__validate(obj, needs_kver), err, out); |
| |
| bpf_object__elf_finish(obj); |
| return obj; |
| out: |
| bpf_object__close(obj); |
| return ERR_PTR(err); |
| } |
| |
| struct bpf_object *__bpf_object__open_xattr(struct bpf_object_open_attr *attr, |
| int flags) |
| { |
| /* param validation */ |
| if (!attr->file) |
| return NULL; |
| |
| pr_debug("loading %s\n", attr->file); |
| |
| return __bpf_object__open(attr->file, NULL, 0, |
| bpf_prog_type__needs_kver(attr->prog_type), |
| flags); |
| } |
| |
| struct bpf_object *bpf_object__open_xattr(struct bpf_object_open_attr *attr) |
| { |
| return __bpf_object__open_xattr(attr, 0); |
| } |
| |
| struct bpf_object *bpf_object__open(const char *path) |
| { |
| struct bpf_object_open_attr attr = { |
| .file = path, |
| .prog_type = BPF_PROG_TYPE_UNSPEC, |
| }; |
| |
| return bpf_object__open_xattr(&attr); |
| } |
| |
| 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); |
| name = tmp_name; |
| } |
| pr_debug("loading object '%s' from buffer\n", name); |
| |
| return __bpf_object__open(name, obj_buf, obj_buf_sz, true, true); |
| } |
| |
| 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_xattr(struct bpf_object_load_attr *attr) |
| { |
| struct bpf_object *obj; |
| int err; |
| |
| if (!attr) |
| return -EINVAL; |
| obj = attr->obj; |
| 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, attr->log_level), err, out); |
| |
| return 0; |
| out: |
| bpf_object__unload(obj); |
| pr_warning("failed to load object '%s'\n", obj->path); |
| return err; |
| } |
| |
| int bpf_object__load(struct bpf_object *obj) |
| { |
| struct bpf_object_load_attr attr = { |
| .obj = obj, |
| }; |
| |
| return bpf_object__load_xattr(&attr); |
| } |
| |
| static int check_path(const char *path) |
| { |
| char *cp, errmsg[STRERR_BUFSIZE]; |
| 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)) { |
| cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
| pr_warning("failed to statfs %s: %s\n", dir, cp); |
| 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) |
| { |
| char *cp, errmsg[STRERR_BUFSIZE]; |
| 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)) { |
| cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
| pr_warning("failed to pin program: %s\n", cp); |
| return -errno; |
| } |
| pr_debug("pinned program '%s'\n", path); |
| |
| return 0; |
| } |
| |
| int bpf_program__unpin_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; |
| } |
| |
| err = unlink(path); |
| if (err != 0) |
| return -errno; |
| pr_debug("unpinned program '%s'\n", path); |
| |
| return 0; |
| } |
| |
| static int make_dir(const char *path) |
| { |
| char *cp, errmsg[STRERR_BUFSIZE]; |
| int err = 0; |
| |
| if (mkdir(path, 0700) && errno != EEXIST) |
| err = -errno; |
| |
| if (err) { |
| cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); |
| pr_warning("failed to mkdir %s: %s\n", path, cp); |
| } |
| 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; |
| } |
| |
| if (prog->instances.nr == 1) { |
| /* don't create subdirs when pinning single instance */ |
| return bpf_program__pin_instance(prog, path, 0); |
| } |
| |
| 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) { |
| err = -EINVAL; |
| goto err_unpin; |
| } else if (len >= PATH_MAX) { |
| err = -ENAMETOOLONG; |
| goto err_unpin; |
| } |
| |
| err = bpf_program__pin_instance(prog, buf, i); |
| if (err) |
| goto err_unpin; |
| } |
| |
| return 0; |
| |
| err_unpin: |
| for (i = i - 1; i >= 0; i--) { |
| char buf[PATH_MAX]; |
| int len; |
| |
| len = snprintf(buf, PATH_MAX, "%s/%d", path, i); |
| if (len < 0) |
| continue; |
| else if (len >= PATH_MAX) |
| continue; |
| |
| bpf_program__unpin_instance(prog, buf, i); |
| } |
| |
| rmdir(path); |
| |
| return err; |
| } |
| |
| int bpf_program__unpin(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; |
| } |
| |
| if (prog->instances.nr == 1) { |
| /* don't create subdirs when pinning single instance */ |
| return bpf_program__unpin_instance(prog, path, 0); |
| } |
| |
| 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__unpin_instance(prog, buf, i); |
| if (err) |
| return err; |
| } |
| |
| err = rmdir(path); |
| if (err) |
| return -errno; |
| |
| return 0; |
| } |
| |
| int bpf_map__pin(struct bpf_map *map, const char *path) |
| { |
| char *cp, errmsg[STRERR_BUFSIZE]; |
| 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)) { |
| cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
| pr_warning("failed to pin map: %s\n", cp); |
| return -errno; |
| } |
| |
| pr_debug("pinned map '%s'\n", path); |
| |
| return 0; |
| } |
| |
| int bpf_map__unpin(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; |
| } |
| |
| err = unlink(path); |
| if (err != 0) |
| return -errno; |
| pr_debug("unpinned map '%s'\n", path); |
| |
| return 0; |
| } |
| |
| int bpf_object__pin_maps(struct bpf_object *obj, const char *path) |
| { |
| 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_object__for_each_map(map, obj) { |
| char buf[PATH_MAX]; |
| int len; |
| |
| len = snprintf(buf, PATH_MAX, "%s/%s", path, |
| bpf_map__name(map)); |
| if (len < 0) { |
| err = -EINVAL; |
| goto err_unpin_maps; |
| } else if (len >= PATH_MAX) { |
| err = -ENAMETOOLONG; |
| goto err_unpin_maps; |
| } |
| |
| err = bpf_map__pin(map, buf); |
| if (err) |
| goto err_unpin_maps; |
| } |
| |
| return 0; |
| |
| err_unpin_maps: |
| while ((map = bpf_map__prev(map, obj))) { |
| char buf[PATH_MAX]; |
| int len; |
| |
| len = snprintf(buf, PATH_MAX, "%s/%s", path, |
| bpf_map__name(map)); |
| if (len < 0) |
| continue; |
| else if (len >= PATH_MAX) |
| continue; |
| |
| bpf_map__unpin(map, buf); |
| } |
| |
| return err; |
| } |
| |
| int bpf_object__unpin_maps(struct bpf_object *obj, const char *path) |
| { |
| struct bpf_map *map; |
| int err; |
| |
| if (!obj) |
| return -ENOENT; |
| |
| bpf_object__for_each_map(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__unpin(map, buf); |
| if (err) |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| int bpf_object__pin_programs(struct bpf_object *obj, const char *path) |
| { |
| struct bpf_program *prog; |
| 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_object__for_each_program(prog, obj) { |
| char buf[PATH_MAX]; |
| int len; |
| |
| len = snprintf(buf, PATH_MAX, "%s/%s", path, |
| prog->pin_name); |
| if (len < 0) { |
| err = -EINVAL; |
| goto err_unpin_programs; |
| } else if (len >= PATH_MAX) { |
| err = -ENAMETOOLONG; |
| goto err_unpin_programs; |
| } |
| |
| err = bpf_program__pin(prog, buf); |
| if (err) |
| goto err_unpin_programs; |
| } |
| |
| return 0; |
| |
| err_unpin_programs: |
| while ((prog = bpf_program__prev(prog, obj))) { |
| char buf[PATH_MAX]; |
| int len; |
| |
| len = snprintf(buf, PATH_MAX, "%s/%s", path, |
| prog->pin_name); |
| if (len < 0) |
| continue; |
| else if (len >= PATH_MAX) |
| continue; |
| |
| bpf_program__unpin(prog, buf); |
| } |
| |
| return err; |
| } |
| |
| int bpf_object__unpin_programs(struct bpf_object *obj, const char *path) |
| { |
| struct bpf_program *prog; |
| int err; |
| |
| if (!obj) |
| return -ENOENT; |
| |
| bpf_object__for_each_program(prog, obj) { |
| char buf[PATH_MAX]; |
| int len; |
| |
| len = snprintf(buf, PATH_MAX, "%s/%s", path, |
| prog->pin_name); |
| if (len < 0) |
| return -EINVAL; |
| else if (len >= PATH_MAX) |
| return -ENAMETOOLONG; |
| |
| err = bpf_program__unpin(prog, buf); |
| if (err) |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| int bpf_object__pin(struct bpf_object *obj, const char *path) |
| { |
| int err; |
| |
| err = bpf_object__pin_maps(obj, path); |
| if (err) |
| return err; |
| |
| err = bpf_object__pin_programs(obj, path); |
| if (err) { |
| bpf_object__unpin_maps(obj, path); |
| 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); |
| btf__free(obj->btf); |
| btf_ext__free(obj->btf_ext); |
| |
| 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->sections.rodata); |
| zfree(&obj->sections.data); |
| 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(const struct bpf_object *obj) |
| { |
| return obj ? obj->path : ERR_PTR(-EINVAL); |
| } |
| |
| unsigned int bpf_object__kversion(const struct bpf_object *obj) |
| { |
| return obj ? obj->kern_version : 0; |
| } |
| |
| struct btf *bpf_object__btf(const struct bpf_object *obj) |
| { |
| return obj ? obj->btf : NULL; |
| } |
| |
| int bpf_object__btf_fd(const struct bpf_object *obj) |
| { |
| return obj->btf ? btf__fd(obj->btf) : -1; |
| } |
| |
| 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(const struct bpf_object *obj) |
| { |
| return obj ? obj->priv : ERR_PTR(-EINVAL); |
| } |
| |
| static struct bpf_program * |
| __bpf_program__iter(const struct bpf_program *p, const struct bpf_object *obj, |
| bool forward) |
| { |
| size_t nr_programs = obj->nr_programs; |
| ssize_t idx; |
| |
| if (!nr_programs) |
| return NULL; |
| |
| if (!p) |
| /* Iter from the beginning */ |
| return forward ? &obj->programs[0] : |
| &obj->programs[nr_programs - 1]; |
| |
| if (p->obj != obj) { |
| pr_warning("error: program handler doesn't match object\n"); |
| return NULL; |
| } |
| |
| idx = (p - obj->programs) + (forward ? 1 : -1); |
| if (idx >= obj->nr_programs || idx < 0) |
| return NULL; |
| return &obj->programs[idx]; |
| } |
| |
| struct bpf_program * |
| bpf_program__next(struct bpf_program *prev, const struct bpf_object *obj) |
| { |
| struct bpf_program *prog = prev; |
| |
| do { |
| prog = __bpf_program__iter(prog, obj, true); |
| } while (prog && bpf_program__is_function_storage(prog, obj)); |
| |
| return prog; |
| } |
| |
| struct bpf_program * |
| bpf_program__prev(struct bpf_program *next, const struct bpf_object *obj) |
| { |
| struct bpf_program *prog = next; |
| |
| do { |
| prog = __bpf_program__iter(prog, obj, false); |
| } while (prog && bpf_program__is_function_storage(prog, obj)); |
| |
| return prog; |
| } |
| |
| 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(const struct bpf_program *prog) |
| { |
| return prog ? prog->priv : ERR_PTR(-EINVAL); |
| } |
| |
| void bpf_program__set_ifindex(struct bpf_program *prog, __u32 ifindex) |
| { |
| prog->prog_ifindex = ifindex; |
| } |
| |
| const char *bpf_program__title(const 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(const 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(const struct bpf_program *prog, int n) |
| { |
| int fd; |
| |
| if (!prog) |
| return -EINVAL; |
| |
| 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(const 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(const 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(raw_tracepoint, BPF_PROG_TYPE_RAW_TRACEPOINT); |
| BPF_PROG_TYPE_FNS(xdp, BPF_PROG_TYPE_XDP); |
| BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT); |
| |
| void bpf_program__set_expected_attach_type(struct bpf_program *prog, |
| enum bpf_attach_type type) |
| { |
| prog->expected_attach_type = type; |
| } |
| |
| #define BPF_PROG_SEC_IMPL(string, ptype, eatype, is_attachable, atype) \ |
| { string, sizeof(string) - 1, ptype, eatype, is_attachable, atype } |
| |
| /* Programs that can NOT be attached. */ |
| #define BPF_PROG_SEC(string, ptype) BPF_PROG_SEC_IMPL(string, ptype, 0, 0, 0) |
| |
| /* Programs that can be attached. */ |
| #define BPF_APROG_SEC(string, ptype, atype) \ |
| BPF_PROG_SEC_IMPL(string, ptype, 0, 1, atype) |
| |
| /* Programs that must specify expected attach type at load time. */ |
| #define BPF_EAPROG_SEC(string, ptype, eatype) \ |
| BPF_PROG_SEC_IMPL(string, ptype, eatype, 1, eatype) |
| |
| /* Programs that can be attached but attach type can't be identified by section |
| * name. Kept for backward compatibility. |
| */ |
| #define BPF_APROG_COMPAT(string, ptype) BPF_PROG_SEC(string, ptype) |
| |
| static const struct { |
| const char *sec; |
| size_t len; |
| enum bpf_prog_type prog_type; |
| enum bpf_attach_type expected_attach_type; |
| int is_attachable; |
| enum bpf_attach_type attach_type; |
| } section_names[] = { |
| BPF_PROG_SEC("socket", BPF_PROG_TYPE_SOCKET_FILTER), |
| BPF_PROG_SEC("kprobe/", BPF_PROG_TYPE_KPROBE), |
| BPF_PROG_SEC("kretprobe/", BPF_PROG_TYPE_KPROBE), |
| BPF_PROG_SEC("classifier", BPF_PROG_TYPE_SCHED_CLS), |
| BPF_PROG_SEC("action", BPF_PROG_TYPE_SCHED_ACT), |
| BPF_PROG_SEC("tracepoint/", BPF_PROG_TYPE_TRACEPOINT), |
| BPF_PROG_SEC("raw_tracepoint/", BPF_PROG_TYPE_RAW_TRACEPOINT), |
| BPF_PROG_SEC("xdp", BPF_PROG_TYPE_XDP), |
| BPF_PROG_SEC("perf_event", BPF_PROG_TYPE_PERF_EVENT), |
| BPF_PROG_SEC("lwt_in", BPF_PROG_TYPE_LWT_IN), |
| BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), |
| BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), |
| BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), |
| BPF_APROG_SEC("cgroup_skb/ingress", BPF_PROG_TYPE_CGROUP_SKB, |
| BPF_CGROUP_INET_INGRESS), |
| BPF_APROG_SEC("cgroup_skb/egress", BPF_PROG_TYPE_CGROUP_SKB, |
| BPF_CGROUP_INET_EGRESS), |
| BPF_APROG_COMPAT("cgroup/skb", BPF_PROG_TYPE_CGROUP_SKB), |
| BPF_APROG_SEC("cgroup/sock", BPF_PROG_TYPE_CGROUP_SOCK, |
| BPF_CGROUP_INET_SOCK_CREATE), |
| BPF_EAPROG_SEC("cgroup/post_bind4", BPF_PROG_TYPE_CGROUP_SOCK, |
| BPF_CGROUP_INET4_POST_BIND), |
| BPF_EAPROG_SEC("cgroup/post_bind6", BPF_PROG_TYPE_CGROUP_SOCK, |
| BPF_CGROUP_INET6_POST_BIND), |
| BPF_APROG_SEC("cgroup/dev", BPF_PROG_TYPE_CGROUP_DEVICE, |
| BPF_CGROUP_DEVICE), |
| BPF_APROG_SEC("sockops", BPF_PROG_TYPE_SOCK_OPS, |
| BPF_CGROUP_SOCK_OPS), |
| BPF_APROG_SEC("sk_skb/stream_parser", BPF_PROG_TYPE_SK_SKB, |
| BPF_SK_SKB_STREAM_PARSER), |
| BPF_APROG_SEC("sk_skb/stream_verdict", BPF_PROG_TYPE_SK_SKB, |
| BPF_SK_SKB_STREAM_VERDICT), |
| BPF_APROG_COMPAT("sk_skb", BPF_PROG_TYPE_SK_SKB), |
| BPF_APROG_SEC("sk_msg", BPF_PROG_TYPE_SK_MSG, |
| BPF_SK_MSG_VERDICT), |
| BPF_APROG_SEC("lirc_mode2", BPF_PROG_TYPE_LIRC_MODE2, |
| BPF_LIRC_MODE2), |
| BPF_APROG_SEC("flow_dissector", BPF_PROG_TYPE_FLOW_DISSECTOR, |
| BPF_FLOW_DISSECTOR), |
| BPF_EAPROG_SEC("cgroup/bind4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
| BPF_CGROUP_INET4_BIND), |
| BPF_EAPROG_SEC("cgroup/bind6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
| BPF_CGROUP_INET6_BIND), |
| BPF_EAPROG_SEC("cgroup/connect4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
| BPF_CGROUP_INET4_CONNECT), |
| BPF_EAPROG_SEC("cgroup/connect6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
| BPF_CGROUP_INET6_CONNECT), |
| BPF_EAPROG_SEC("cgroup/sendmsg4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
| BPF_CGROUP_UDP4_SENDMSG), |
| BPF_EAPROG_SEC("cgroup/sendmsg6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
| BPF_CGROUP_UDP6_SENDMSG), |
| BPF_EAPROG_SEC("cgroup/recvmsg4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
| BPF_CGROUP_UDP4_RECVMSG), |
| BPF_EAPROG_SEC("cgroup/recvmsg6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
| BPF_CGROUP_UDP6_RECVMSG), |
| BPF_EAPROG_SEC("cgroup/sysctl", BPF_PROG_TYPE_CGROUP_SYSCTL, |
| BPF_CGROUP_SYSCTL), |
| BPF_EAPROG_SEC("cgroup/getsockopt", BPF_PROG_TYPE_CGROUP_SOCKOPT, |
| BPF_CGROUP_GETSOCKOPT), |
| BPF_EAPROG_SEC("cgroup/setsockopt", BPF_PROG_TYPE_CGROUP_SOCKOPT, |
| BPF_CGROUP_SETSOCKOPT), |
| }; |
| |
| #undef BPF_PROG_SEC_IMPL |
| #undef BPF_PROG_SEC |
| #undef BPF_APROG_SEC |
| #undef BPF_EAPROG_SEC |
| #undef BPF_APROG_COMPAT |
| |
| #define MAX_TYPE_NAME_SIZE 32 |
| |
| static char *libbpf_get_type_names(bool attach_type) |
| { |
| int i, len = ARRAY_SIZE(section_names) * MAX_TYPE_NAME_SIZE; |
| char *buf; |
| |
| buf = malloc(len); |
| if (!buf) |
| return NULL; |
| |
| buf[0] = '\0'; |
| /* Forge string buf with all available names */ |
| for (i = 0; i < ARRAY_SIZE(section_names); i++) { |
| if (attach_type && !section_names[i].is_attachable) |
| continue; |
| |
| if (strlen(buf) + strlen(section_names[i].sec) + 2 > len) { |
| free(buf); |
| return NULL; |
| } |
| strcat(buf, " "); |
| strcat(buf, section_names[i].sec); |
| } |
| |
| return buf; |
| } |
| |
| int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, |
| enum bpf_attach_type *expected_attach_type) |
| { |
| char *type_names; |
| int i; |
| |
| if (!name) |
| return -EINVAL; |
| |
| for (i = 0; i < ARRAY_SIZE(section_names); i++) { |
| if (strncmp(name, section_names[i].sec, section_names[i].len)) |
| continue; |
| *prog_type = section_names[i].prog_type; |
| *expected_attach_type = section_names[i].expected_attach_type; |
| return 0; |
| } |
| pr_warning("failed to guess program type based on ELF section name '%s'\n", name); |
| type_names = libbpf_get_type_names(false); |
| if (type_names != NULL) { |
| pr_info("supported section(type) names are:%s\n", type_names); |
| free(type_names); |
| } |
| |
| return -EINVAL; |
| } |
| |
| int libbpf_attach_type_by_name(const char *name, |
| enum bpf_attach_type *attach_type) |
| { |
| char *type_names; |
| int i; |
| |
| if (!name) |
| return -EINVAL; |
| |
| for (i = 0; i < ARRAY_SIZE(section_names); i++) { |
| if (strncmp(name, section_names[i].sec, section_names[i].len)) |
| continue; |
| if (!section_names[i].is_attachable) |
| return -EINVAL; |
| *attach_type = section_names[i].attach_type; |
| return 0; |
| } |
| pr_warning("failed to guess attach type based on ELF section name '%s'\n", name); |
| type_names = libbpf_get_type_names(true); |
| if (type_names != NULL) { |
| pr_info("attachable section(type) names are:%s\n", type_names); |
| free(type_names); |
| } |
| |
| return -EINVAL; |
| } |
| |
| static int |
| bpf_program__identify_section(struct bpf_program *prog, |
| enum bpf_prog_type *prog_type, |
| enum bpf_attach_type *expected_attach_type) |
| { |
| return libbpf_prog_type_by_name(prog->section_name, prog_type, |
| expected_attach_type); |
| } |
| |
| int bpf_map__fd(const struct bpf_map *map) |
| { |
| return map ? map->fd : -EINVAL; |
| } |
| |
| const struct bpf_map_def *bpf_map__def(const struct bpf_map *map) |
| { |
| return map ? &map->def : ERR_PTR(-EINVAL); |
| } |
| |
| const char *bpf_map__name(const struct bpf_map *map) |
| { |
| return map ? map->name : NULL; |
| } |
| |
| __u32 bpf_map__btf_key_type_id(const struct bpf_map *map) |
| { |
| return map ? map->btf_key_type_id : 0; |
| } |
| |
| __u32 bpf_map__btf_value_type_id(const struct bpf_map *map) |
| { |
| return map ? map->btf_value_type_id : 0; |
| } |
| |
| 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(const struct bpf_map *map) |
| { |
| return map ? map->priv : ERR_PTR(-EINVAL); |
| } |
| |
| bool bpf_map__is_offload_neutral(const struct bpf_map *map) |
| { |
| return map->def.type == BPF_MAP_TYPE_PERF_EVENT_ARRAY; |
| } |
| |
| bool bpf_map__is_internal(const struct bpf_map *map) |
| { |
| return map->libbpf_type != LIBBPF_MAP_UNSPEC; |
| } |
| |
| void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex) |
| { |
| map->map_ifindex = ifindex; |
| } |
| |
| int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd) |
| { |
| if (!bpf_map_type__is_map_in_map(map->def.type)) { |
| pr_warning("error: unsupported map type\n"); |
| return -EINVAL; |
| } |
| if (map->inner_map_fd != -1) { |
| pr_warning("error: inner_map_fd already specified\n"); |
| return -EINVAL; |
| } |
| map->inner_map_fd = fd; |
| return 0; |
| } |
| |
| static struct bpf_map * |
| __bpf_map__iter(const struct bpf_map *m, const struct bpf_object *obj, int i) |
| { |
| ssize_t idx; |
| struct bpf_map *s, *e; |
| |
| if (!obj || !obj->maps) |
| return NULL; |
| |
| s = obj->maps; |
| e = obj->maps + obj->nr_maps; |
| |
| if ((m < s) || (m >= e)) { |
| pr_warning("error in %s: map handler doesn't belong to object\n", |
| __func__); |
| return NULL; |
| } |
| |
| idx = (m - obj->maps) + i; |
| if (idx >= obj->nr_maps || idx < 0) |
| return NULL; |
| return &obj->maps[idx]; |
| } |
| |
| struct bpf_map * |
| bpf_map__next(const struct bpf_map *prev, const struct bpf_object *obj) |
| { |
| if (prev == NULL) |
| return obj->maps; |
| |
| return __bpf_map__iter(prev, obj, 1); |
| } |
| |
| struct bpf_map * |
| bpf_map__prev(const struct bpf_map *next, const struct bpf_object *obj) |
| { |
| if (next == NULL) { |
| if (!obj->nr_maps) |
| return NULL; |
| return obj->maps + obj->nr_maps - 1; |
| } |
| |
| return __bpf_map__iter(next, obj, -1); |
| } |
| |
| struct bpf_map * |
| bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name) |
| { |
| struct bpf_map *pos; |
| |
| bpf_object__for_each_map(pos, obj) { |
| if (pos->name && !strcmp(pos->name, name)) |
| return pos; |
| } |
| return NULL; |
| } |
| |
| int |
| bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name) |
| { |
| return bpf_map__fd(bpf_object__find_map_by_name(obj, name)); |
| } |
| |
| struct bpf_map * |
| bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset) |
| { |
| return ERR_PTR(-ENOTSUP); |
| } |
| |
| long libbpf_get_error(const void *ptr) |
| { |
| return PTR_ERR_OR_ZERO(ptr); |
| } |
| |
| int bpf_prog_load(const char *file, enum bpf_prog_type type, |
| struct bpf_object **pobj, int *prog_fd) |
| { |
| struct bpf_prog_load_attr attr; |
| |
| memset(&attr, 0, sizeof(struct bpf_prog_load_attr)); |
| attr.file = file; |
| attr.prog_type = type; |
| attr.expected_attach_type = 0; |
| |
| return bpf_prog_load_xattr(&attr, pobj, prog_fd); |
| } |
| |
| int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, |
| struct bpf_object **pobj, int *prog_fd) |
| { |
| struct bpf_object_open_attr open_attr = {}; |
| struct bpf_program *prog, *first_prog = NULL; |
| enum bpf_attach_type expected_attach_type; |
| enum bpf_prog_type prog_type; |
| struct bpf_object *obj; |
| struct bpf_map *map; |
| int err; |
| |
| if (!attr) |
| return -EINVAL; |
| if (!attr->file) |
| return -EINVAL; |
| |
| open_attr.file = attr->file; |
| open_attr.prog_type = attr->prog_type; |
| |
| obj = bpf_object__open_xattr(&open_attr); |
| if (IS_ERR_OR_NULL(obj)) |
| return -ENOENT; |
| |
| bpf_object__for_each_program(prog, obj) { |
| /* |
| * If type is not specified, try to guess it based on |
| * section name. |
| */ |
| prog_type = attr->prog_type; |
| prog->prog_ifindex = attr->ifindex; |
| expected_attach_type = attr->expected_attach_type; |
| if (prog_type == BPF_PROG_TYPE_UNSPEC) { |
| err = bpf_program__identify_section(prog, &prog_type, |
| &expected_attach_type); |
| if (err < 0) { |
| bpf_object__close(obj); |
| return -EINVAL; |
| } |
| } |
| |
| bpf_program__set_type(prog, prog_type); |
| bpf_program__set_expected_attach_type(prog, |
| expected_attach_type); |
| |
| prog->log_level = attr->log_level; |
| prog->prog_flags = attr->prog_flags; |
| if (!first_prog) |
| first_prog = prog; |
| } |
| |
| bpf_object__for_each_map(map, obj) { |
| if (!bpf_map__is_offload_neutral(map)) |
| map->map_ifindex = attr->ifindex; |
| } |
| |
| if (!first_prog) { |
| pr_warning("object file doesn't contain bpf program\n"); |
| bpf_object__close(obj); |
| return -ENOENT; |
| } |
| |
| err = bpf_object__load(obj); |
| if (err) { |
| bpf_object__close(obj); |
| return -EINVAL; |
| } |
| |
| *pobj = obj; |
| *prog_fd = bpf_program__fd(first_prog); |
| return 0; |
| } |
| |
| struct bpf_link { |
| int (*destroy)(struct bpf_link *link); |
| }; |
| |
| int bpf_link__destroy(struct bpf_link *link) |
| { |
| int err; |
| |
| if (!link) |
| return 0; |
| |
| err = link->destroy(link); |
| free(link); |
| |
| return err; |
| } |
| |
| struct bpf_link_fd { |
| struct bpf_link link; /* has to be at the top of struct */ |
| int fd; /* hook FD */ |
| }; |
| |
| static int bpf_link__destroy_perf_event(struct bpf_link *link) |
| { |
| struct bpf_link_fd *l = (void *)link; |
| int err; |
| |
| err = ioctl(l->fd, PERF_EVENT_IOC_DISABLE, 0); |
| if (err) |
| err = -errno; |
| |
| close(l->fd); |
| return err; |
| } |
| |
| struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog, |
| int pfd) |
| { |
| char errmsg[STRERR_BUFSIZE]; |
| struct bpf_link_fd *link; |
| int prog_fd, err; |
| |
| if (pfd < 0) { |
| pr_warning("program '%s': invalid perf event FD %d\n", |
| bpf_program__title(prog, false), pfd); |
| return ERR_PTR(-EINVAL); |
| } |
| prog_fd = bpf_program__fd(prog); |
| if (prog_fd < 0) { |
| pr_warning("program '%s': can't attach BPF program w/o FD (did you load it?)\n", |
| bpf_program__title(prog, false)); |
| return ERR_PTR(-EINVAL); |
| } |
| |
| link = malloc(sizeof(*link)); |
| if (!link) |
| return ERR_PTR(-ENOMEM); |
| link->link.destroy = &bpf_link__destroy_perf_event; |
| link->fd = pfd; |
| |
| if (ioctl(pfd, PERF_EVENT_IOC_SET_BPF, prog_fd) < 0) { |
| err = -errno; |
| free(link); |
| pr_warning("program '%s': failed to attach to pfd %d: %s\n", |
| bpf_program__title(prog, false), pfd, |
| libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
| return ERR_PTR(err); |
| } |
| if (ioctl(pfd, PERF_EVENT_IOC_ENABLE, 0) < 0) { |
| err = -errno; |
| free(link); |
| pr_warning("program '%s': failed to enable pfd %d: %s\n", |
| bpf_program__title(prog, false), pfd, |
| libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
| return ERR_PTR(err); |
| } |
| return (struct bpf_link *)link; |
| } |
| |
| /* |
| * this function is expected to parse integer in the range of [0, 2^31-1] from |
| * given file using scanf format string fmt. If actual parsed value is |
| * negative, the result might be indistinguishable from error |
| */ |
| static int parse_uint_from_file(const char *file, const char *fmt) |
| { |
| char buf[STRERR_BUFSIZE]; |
| int err, ret; |
| FILE *f; |
| |
| f = fopen(file, "r"); |
| if (!f) { |
| err = -errno; |
| pr_debug("failed to open '%s': %s\n", file, |
| libbpf_strerror_r(err, buf, sizeof(buf))); |
| return err; |
| } |
| err = fscanf(f, fmt, &ret); |
| if (err != 1) { |
| err = err == EOF ? -EIO : -errno; |
| pr_debug("failed to parse '%s': %s\n", file, |
| libbpf_strerror_r(err, buf, sizeof(buf))); |
| fclose(f); |
| return err; |
| } |
| fclose(f); |
| return ret; |
| } |
| |
| static int determine_kprobe_perf_type(void) |
| { |
| const char *file = "/sys/bus/event_source/devices/kprobe/type"; |
| |
| return parse_uint_from_file(file, "%d\n"); |
| } |
| |
| static int determine_uprobe_perf_type(void) |
| { |
| const char *file = "/sys/bus/event_source/devices/uprobe/type"; |
| |
| return parse_uint_from_file(file, "%d\n"); |
| } |
| |
| static int determine_kprobe_retprobe_bit(void) |
| { |
| const char *file = "/sys/bus/event_source/devices/kprobe/format/retprobe"; |
| |
| return parse_uint_from_file(file, "config:%d\n"); |
| } |
| |
| static int determine_uprobe_retprobe_bit(void) |
| { |
| const char *file = "/sys/bus/event_source/devices/uprobe/format/retprobe"; |
| |
| return parse_uint_from_file(file, "config:%d\n"); |
| } |
| |
| static int perf_event_open_probe(bool uprobe, bool retprobe, const char *name, |
| uint64_t offset, int pid) |
| { |
| struct perf_event_attr attr = {}; |
| char errmsg[STRERR_BUFSIZE]; |
| int type, pfd, err; |
| |
| type = uprobe ? determine_uprobe_perf_type() |
| : determine_kprobe_perf_type(); |
| if (type < 0) { |
| pr_warning("failed to determine %s perf type: %s\n", |
| uprobe ? "uprobe" : "kprobe", |
| libbpf_strerror_r(type, errmsg, sizeof(errmsg))); |
| return type; |
| } |
| if (retprobe) { |
| int bit = uprobe ? determine_uprobe_retprobe_bit() |
| : determine_kprobe_retprobe_bit(); |
| |
| if (bit < 0) { |
| pr_warning("failed to determine %s retprobe bit: %s\n", |
| uprobe ? "uprobe" : "kprobe", |
| libbpf_strerror_r(bit, errmsg, |
| sizeof(errmsg))); |
| return bit; |
| } |
| attr.config |= 1 << bit; |
| } |
| attr.size = sizeof(attr); |
| attr.type = type; |
| attr.config1 = ptr_to_u64(name); /* kprobe_func or uprobe_path */ |
| attr.config2 = offset; /* kprobe_addr or probe_offset */ |
| |
| /* pid filter is meaningful only for uprobes */ |
| pfd = syscall(__NR_perf_event_open, &attr, |
| pid < 0 ? -1 : pid /* pid */, |
| pid == -1 ? 0 : -1 /* cpu */, |
| -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); |
| if (pfd < 0) { |
| err = -errno; |
| pr_warning("%s perf_event_open() failed: %s\n", |
| uprobe ? "uprobe" : "kprobe", |
| libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
| return err; |
| } |
| return pfd; |
| } |
| |
| struct bpf_link *bpf_program__attach_kprobe(struct bpf_program *prog, |
| bool retprobe, |
| const char *func_name) |
| { |
| char errmsg[STRERR_BUFSIZE]; |
| struct bpf_link *link; |
| int pfd, err; |
| |
| pfd = perf_event_open_probe(false /* uprobe */, retprobe, func_name, |
| 0 /* offset */, -1 /* pid */); |
| if (pfd < 0) { |
| pr_warning("program '%s': failed to create %s '%s' perf event: %s\n", |
| bpf_program__title(prog, false), |
| retprobe ? "kretprobe" : "kprobe", func_name, |
| libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); |
| return ERR_PTR(pfd); |
| } |
| link = bpf_program__attach_perf_event(prog, pfd); |
| if (IS_ERR(link)) { |
| close(pfd); |
| err = PTR_ERR(link); |
| pr_warning("program '%s': failed to attach to %s '%s': %s\n", |
| bpf_program__title(prog, false), |
| retprobe ? "kretprobe" : "kprobe", func_name, |
| libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
| return link; |
| } |
| return link; |
| } |
| |
| struct bpf_link *bpf_program__attach_uprobe(struct bpf_program *prog, |
| bool retprobe, pid_t pid, |
| const char *binary_path, |
| size_t func_offset) |
| { |
| char errmsg[STRERR_BUFSIZE]; |
| struct bpf_link *link; |
| int pfd, err; |
| |
| pfd = perf_event_open_probe(true /* uprobe */, retprobe, |
| binary_path, func_offset, pid); |
| if (pfd < 0) { |
| pr_warning("program '%s': failed to create %s '%s:0x%zx' perf event: %s\n", |
| bpf_program__title(prog, false), |
| retprobe ? "uretprobe" : "uprobe", |
| binary_path, func_offset, |
| libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); |
| return ERR_PTR(pfd); |
| } |
| link = bpf_program__attach_perf_event(prog, pfd); |
| if (IS_ERR(link)) { |
| close(pfd); |
| err = PTR_ERR(link); |
| pr_warning("program '%s': failed to attach to %s '%s:0x%zx': %s\n", |
| bpf_program__title(prog, false), |
| retprobe ? "uretprobe" : "uprobe", |
| binary_path, func_offset, |
| libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
| return link; |
| } |
| return link; |
| } |
| |
| static int determine_tracepoint_id(const char *tp_category, |
| const char *tp_name) |
| { |
| char file[PATH_MAX]; |
| int ret; |
| |
| ret = snprintf(file, sizeof(file), |
| "/sys/kernel/debug/tracing/events/%s/%s/id", |
| tp_category, tp_name); |
| if (ret < 0) |
| return -errno; |
| if (ret >= sizeof(file)) { |
| pr_debug("tracepoint %s/%s path is too long\n", |
| tp_category, tp_name); |
| return -E2BIG; |
| } |
| return parse_uint_from_file(file, "%d\n"); |
| } |
| |
| static int perf_event_open_tracepoint(const char *tp_category, |
| const char *tp_name) |
| { |
| struct perf_event_attr attr = {}; |
| char errmsg[STRERR_BUFSIZE]; |
| int tp_id, pfd, err; |
| |
| tp_id = determine_tracepoint_id(tp_category, tp_name); |
| if (tp_id < 0) { |
| pr_warning("failed to determine tracepoint '%s/%s' perf event ID: %s\n", |
| tp_category, tp_name, |
| libbpf_strerror_r(tp_id, errmsg, sizeof(errmsg))); |
| return tp_id; |
| } |
| |
| attr.type = PERF_TYPE_TRACEPOINT; |
| attr.size = sizeof(attr); |
| attr.config = tp_id; |
| |
| pfd = syscall(__NR_perf_event_open, &attr, -1 /* pid */, 0 /* cpu */, |
| -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); |
| if (pfd < 0) { |
| err = -errno; |
| pr_warning("tracepoint '%s/%s' perf_event_open() failed: %s\n", |
| tp_category, tp_name, |
| libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
| return err; |
| } |
| return pfd; |
| } |
| |
| struct bpf_link *bpf_program__attach_tracepoint(struct bpf_program *prog, |
| const char *tp_category, |
| const char *tp_name) |
| { |
| char errmsg[STRERR_BUFSIZE]; |
| struct bpf_link *link; |
| int pfd, err; |
| |
| pfd = perf_event_open_tracepoint(tp_category, tp_name); |
| if (pfd < 0) { |
| pr_warning("program '%s': failed to create tracepoint '%s/%s' perf event: %s\n", |
| bpf_program__title(prog, false), |
| tp_category, tp_name, |
| libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); |
| return ERR_PTR(pfd); |
| } |
| link = bpf_program__attach_perf_event(prog, pfd); |
| if (IS_ERR(link)) { |
| close(pfd); |
| err = PTR_ERR(link); |
| pr_warning("program '%s': failed to attach to tracepoint '%s/%s': %s\n", |
| bpf_program__title(prog, false), |
| tp_category, tp_name, |
| libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
| return link; |
| } |
| return link; |
| } |
| |
| static int bpf_link__destroy_fd(struct bpf_link *link) |
| { |
| struct bpf_link_fd *l = (void *)link; |
| |
| return close(l->fd); |
| } |
| |
| struct bpf_link *bpf_program__attach_raw_tracepoint(struct bpf_program *prog, |
| const char *tp_name) |
| { |
| char errmsg[STRERR_BUFSIZE]; |
| struct bpf_link_fd *link; |
| int prog_fd, pfd; |
| |
| prog_fd = bpf_program__fd(prog); |
| if (prog_fd < 0) { |
| pr_warning("program '%s': can't attach before loaded\n", |
| bpf_program__title(prog, false)); |
| return ERR_PTR(-EINVAL); |
| } |
| |
| link = malloc(sizeof(*link)); |
| if (!link) |
| return ERR_PTR(-ENOMEM); |
| link->link.destroy = &bpf_link__destroy_fd; |
| |
| pfd = bpf_raw_tracepoint_open(tp_name, prog_fd); |
| if (pfd < 0) { |
| pfd = -errno; |
| free(link); |
| pr_warning("program '%s': failed to attach to raw tracepoint '%s': %s\n", |
| bpf_program__title(prog, false), tp_name, |
| libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); |
| return ERR_PTR(pfd); |
| } |
| link->fd = pfd; |
| return (struct bpf_link *)link; |
| } |
| |
| enum bpf_perf_event_ret |
| bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size, |
| void **copy_mem, size_t *copy_size, |
| bpf_perf_event_print_t fn, void *private_data) |
| { |
| struct perf_event_mmap_page *header = mmap_mem; |
| __u64 data_head = ring_buffer_read_head(header); |
| __u64 data_tail = header->data_tail; |
| void *base = ((__u8 *)header) + page_size; |
| int ret = LIBBPF_PERF_EVENT_CONT; |
| struct perf_event_header *ehdr; |
| size_t ehdr_size; |
| |
| while (data_head != data_tail) { |
| ehdr = base + (data_tail & (mmap_size - 1)); |
| ehdr_size = ehdr->size; |
| |
| if (((void *)ehdr) + ehdr_size > base + mmap_size) { |
| void *copy_start = ehdr; |
| size_t len_first = base + mmap_size - copy_start; |
| size_t len_secnd = ehdr_size - len_first; |
| |
| if (*copy_size < ehdr_size) { |
| free(*copy_mem); |
| *copy_mem = malloc(ehdr_size); |
| if (!*copy_mem) { |
| *copy_size = 0; |
| ret = LIBBPF_PERF_EVENT_ERROR; |
| break; |
| } |
| *copy_size = ehdr_size; |
| } |
| |
| memcpy(*copy_mem, copy_start, len_first); |
| memcpy(*copy_mem + len_first, base, len_secnd); |
| ehdr = *copy_mem; |
| } |
| |
| ret = fn(ehdr, private_data); |
| data_tail += ehdr_size; |
| if (ret != LIBBPF_PERF_EVENT_CONT) |
| break; |
| } |
| |
| ring_buffer_write_tail(header, data_tail); |
| return ret; |
| } |
| |
| struct perf_buffer; |
| |
| struct perf_buffer_params { |
| struct perf_event_attr *attr; |
| /* if event_cb is specified, it takes precendence */ |
| perf_buffer_event_fn event_cb; |
| /* sample_cb and lost_cb are higher-level common-case callbacks */ |
| perf_buffer_sample_fn sample_cb; |
| perf_buffer_lost_fn lost_cb; |
| void *ctx; |
| int cpu_cnt; |
| int *cpus; |
| int *map_keys; |
| }; |
| |
| struct perf_cpu_buf { |
| struct perf_buffer *pb; |
| void *base; /* mmap()'ed memory */ |
| void *buf; /* for reconstructing segmented data */ |
| size_t buf_size; |
| int fd; |
| int cpu; |
| int map_key; |
| }; |
| |
| struct perf_buffer { |
| perf_buffer_event_fn event_cb; |
| perf_buffer_sample_fn sample_cb; |
| perf_buffer_lost_fn lost_cb; |
| void *ctx; /* passed into callbacks */ |
| |
| size_t page_size; |
| size_t mmap_size; |
| struct perf_cpu_buf **cpu_bufs; |
| struct epoll_event *events; |
| int cpu_cnt; |
| int epoll_fd; /* perf event FD */ |
| int map_fd; /* BPF_MAP_TYPE_PERF_EVENT_ARRAY BPF map FD */ |
| }; |
| |
| static void perf_buffer__free_cpu_buf(struct perf_buffer *pb, |
| struct perf_cpu_buf *cpu_buf) |
| { |
| if (!cpu_buf) |
| return; |
| if (cpu_buf->base && |
| munmap(cpu_buf->base, pb->mmap_size + pb->page_size)) |
| pr_warning("failed to munmap cpu_buf #%d\n", cpu_buf->cpu); |
| if (cpu_buf->fd >= 0) { |
| ioctl(cpu_buf->fd, PERF_EVENT_IOC_DISABLE, 0); |
| close(cpu_buf->fd); |
| } |
| free(cpu_buf->buf); |
| free(cpu_buf); |
| } |
| |
| void perf_buffer__free(struct perf_buffer *pb) |
| { |
| int i; |
| |
| if (!pb) |
| return; |
| if (pb->cpu_bufs) { |
| for (i = 0; i < pb->cpu_cnt && pb->cpu_bufs[i]; i++) { |
| struct perf_cpu_buf *cpu_buf = pb->cpu_bufs[i]; |
| |
| bpf_map_delete_elem(pb->map_fd, &cpu_buf->map_key); |
| perf_buffer__free_cpu_buf(pb, cpu_buf); |
| } |
| free(pb->cpu_bufs); |
| } |
| if (pb->epoll_fd >= 0) |
| close(pb->epoll_fd); |
| free(pb->events); |
| free(pb); |
| } |
| |
| static struct perf_cpu_buf * |
| perf_buffer__open_cpu_buf(struct perf_buffer *pb, struct perf_event_attr *attr, |
| int cpu, int map_key) |
| { |
| struct perf_cpu_buf *cpu_buf; |
| char msg[STRERR_BUFSIZE]; |
| int err; |
| |
| cpu_buf = calloc(1, sizeof(*cpu_buf)); |
| if (!cpu_buf) |
| return ERR_PTR(-ENOMEM); |
| |
| cpu_buf->pb = pb; |
| cpu_buf->cpu = cpu; |
| cpu_buf->map_key = map_key; |
| |
| cpu_buf->fd = syscall(__NR_perf_event_open, attr, -1 /* pid */, cpu, |
| -1, PERF_FLAG_FD_CLOEXEC); |
| if (cpu_buf->fd < 0) { |
| err = -errno; |
| pr_warning("failed to open perf buffer event on cpu #%d: %s\n", |
| cpu, libbpf_strerror_r(err, msg, sizeof(msg))); |
| goto error; |
| } |
| |
| cpu_buf->base = mmap(NULL, pb->mmap_size + pb->page_size, |
| PROT_READ | PROT_WRITE, MAP_SHARED, |
| cpu_buf->fd, 0); |
| if (cpu_buf->base == MAP_FAILED) { |
| cpu_buf->base = NULL; |
| err = -errno; |
| pr_warning("failed to mmap perf buffer on cpu #%d: %s\n", |
| cpu, libbpf_strerror_r(err, msg, sizeof(msg))); |
| goto error; |
| } |
| |
| if (ioctl(cpu_buf->fd, PERF_EVENT_IOC_ENABLE, 0) < 0) { |
| err = -errno; |
| pr_warning("failed to enable perf buffer event on cpu #%d: %s\n", |
| cpu, libbpf_strerror_r(err, msg, sizeof(msg))); |
| goto error; |
| } |
| |
| return cpu_buf; |
| |
| error: |
| perf_buffer__free_cpu_buf(pb, cpu_buf); |
| return (struct perf_cpu_buf *)ERR_PTR(err); |
| } |
| |
| static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, |
| struct perf_buffer_params *p); |
| |
| struct perf_buffer *perf_buffer__new(int map_fd, size_t page_cnt, |
| const struct perf_buffer_opts *opts) |
| { |
| struct perf_buffer_params p = {}; |
| struct perf_event_attr attr = { 0, }; |
| |
| attr.config = PERF_COUNT_SW_BPF_OUTPUT, |
| attr.type = PERF_TYPE_SOFTWARE; |
| attr.sample_type = PERF_SAMPLE_RAW; |
| attr.sample_period = 1; |
| attr.wakeup_events = 1; |
| |
| p.attr = &attr; |
| p.sample_cb = opts ? opts->sample_cb : NULL; |
| p.lost_cb = opts ? opts->lost_cb : NULL; |
| p.ctx = opts ? opts->ctx : NULL; |
| |
| return __perf_buffer__new(map_fd, page_cnt, &p); |
| } |
| |
| struct perf_buffer * |
| perf_buffer__new_raw(int map_fd, size_t page_cnt, |
| const struct perf_buffer_raw_opts *opts) |
| { |
| struct perf_buffer_params p = {}; |
| |
| p.attr = opts->attr; |
| p.event_cb = opts->event_cb; |
| p.ctx = opts->ctx; |
| p.cpu_cnt = opts->cpu_cnt; |
| p.cpus = opts->cpus; |
| p.map_keys = opts->map_keys; |
| |
| return __perf_buffer__new(map_fd, page_cnt, &p); |
| } |
| |
| static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, |
| struct perf_buffer_params *p) |
| { |
| struct bpf_map_info map = {}; |
| char msg[STRERR_BUFSIZE]; |
| struct perf_buffer *pb; |
| __u32 map_info_len; |
| int err, i; |
| |
| if (page_cnt & (page_cnt - 1)) { |
| pr_warning("page count should be power of two, but is %zu\n", |
| page_cnt); |
| return ERR_PTR(-EINVAL); |
| } |
| |
| map_info_len = sizeof(map); |
| err = bpf_obj_get_info_by_fd(map_fd, &map, &map_info_len); |
| if (err) { |
| err = -errno; |
| pr_warning("failed to get map info for map FD %d: %s\n", |
| map_fd, libbpf_strerror_r(err, msg, sizeof(msg))); |
| return ERR_PTR(err); |
| } |
| |
| if (map.type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) { |
| pr_warning("map '%s' should be BPF_MAP_TYPE_PERF_EVENT_ARRAY\n", |
| map.name); |
| return ERR_PTR(-EINVAL); |
| } |
| |
| pb = calloc(1, sizeof(*pb)); |
| if (!pb) |
| return ERR_PTR(-ENOMEM); |
| |
| pb->event_cb = p->event_cb; |
| pb->sample_cb = p->sample_cb; |
| pb->lost_cb = p->lost_cb; |
| pb->ctx = p->ctx; |
| |
| pb->page_size = getpagesize(); |
| pb->mmap_size = pb->page_size * page_cnt; |
| pb->map_fd = map_fd; |
| |
| pb->epoll_fd = epoll_create1(EPOLL_CLOEXEC); |
| if (pb->epoll_fd < 0) { |
| err = -errno; |
| pr_warning("failed to create epoll instance: %s\n", |
| libbpf_strerror_r(err, msg, sizeof(msg))); |
| goto error; |
| } |
| |
| if (p->cpu_cnt > 0) { |
| pb->cpu_cnt = p->cpu_cnt; |
| } else { |
| pb->cpu_cnt = libbpf_num_possible_cpus(); |
| if (pb->cpu_cnt < 0) { |
| err = pb->cpu_cnt; |
| goto error; |
| } |
| if (map.max_entries < pb->cpu_cnt) |
| pb->cpu_cnt = map.max_entries; |
| } |
| |
| pb->events = calloc(pb->cpu_cnt, sizeof(*pb->events)); |
| if (!pb->events) { |
| err = -ENOMEM; |
| pr_warning("failed to allocate events: out of memory\n"); |
| goto error; |
| } |
| pb->cpu_bufs = calloc(pb->cpu_cnt, sizeof(*pb->cpu_bufs)); |
| if (!pb->cpu_bufs) { |
| err = -ENOMEM; |
| pr_warning("failed to allocate buffers: out of memory\n"); |
| goto error; |
| } |
| |
| for (i = 0; i < pb->cpu_cnt; i++) { |
| struct perf_cpu_buf *cpu_buf; |
| int cpu, map_key; |
| |
| cpu = p->cpu_cnt > 0 ? p->cpus[i] : i; |
| map_key = p->cpu_cnt > 0 ? p->map_keys[i] : i; |
| |
| cpu_buf = perf_buffer__open_cpu_buf(pb, p->attr, cpu, map_key); |
| if (IS_ERR(cpu_buf)) { |
| err = PTR_ERR(cpu_buf); |
| goto error; |
| } |
| |
| pb->cpu_bufs[i] = cpu_buf; |
| |
| err = bpf_map_update_elem(pb->map_fd, &map_key, |
| &cpu_buf->fd, 0); |
| if (err) { |
| err = -errno; |
| pr_warning("failed to set cpu #%d, key %d -> perf FD %d: %s\n", |
| cpu, map_key, cpu_buf->fd, |
| libbpf_strerror_r(err, msg, sizeof(msg))); |
| goto error; |
| } |
| |
| pb->events[i].events = EPOLLIN; |
| pb->events[i].data.ptr = cpu_buf; |
| if (epoll_ctl(pb->epoll_fd, EPOLL_CTL_ADD, cpu_buf->fd, |
| &pb->events[i]) < 0) { |
| err = -errno; |
| pr_warning("failed to epoll_ctl cpu #%d perf FD %d: %s\n", |
| cpu, cpu_buf->fd, |
| libbpf_strerror_r(err, msg, sizeof(msg))); |
| goto error; |
| } |
| } |
| |
| return pb; |
| |
| error: |
| if (pb) |
| perf_buffer__free(pb); |
| return ERR_PTR(err); |
| } |
| |
| struct perf_sample_raw { |
| struct perf_event_header header; |
| uint32_t size; |
| char data[0]; |
| }; |
| |
| struct perf_sample_lost { |
| struct perf_event_header header; |
| uint64_t id; |
| uint64_t lost; |
| uint64_t sample_id; |
| }; |
| |
| static enum bpf_perf_event_ret |
| perf_buffer__process_record(struct perf_event_header *e, void *ctx) |
| { |
| struct perf_cpu_buf *cpu_buf = ctx; |
| struct perf_buffer *pb = cpu_buf->pb; |
| void *data = e; |
| |
| /* user wants full control over parsing perf event */ |
| if (pb->event_cb) |
| return pb->event_cb(pb->ctx, cpu_buf->cpu, e); |
| |
| switch (e->type) { |
| case PERF_RECORD_SAMPLE: { |
| struct perf_sample_raw *s = data; |
| |
| if (pb->sample_cb) |
| pb->sample_cb(pb->ctx, cpu_buf->cpu, s->data, s->size); |
| break; |
| } |
| case PERF_RECORD_LOST: { |
| struct perf_sample_lost *s = data; |
| |
| if (pb->lost_cb) |
| pb->lost_cb(pb->ctx, cpu_buf->cpu, s->lost); |
| break; |
| } |
| default: |
| pr_warning("unknown perf sample type %d\n", e->type); |
| return LIBBPF_PERF_EVENT_ERROR; |
| } |
| return LIBBPF_PERF_EVENT_CONT; |
| } |
| |
| static int perf_buffer__process_records(struct perf_buffer *pb, |
| struct perf_cpu_buf *cpu_buf) |
| { |
| enum bpf_perf_event_ret ret; |
| |
| ret = bpf_perf_event_read_simple(cpu_buf->base, pb->mmap_size, |
| pb->page_size, &cpu_buf->buf, |
| &cpu_buf->buf_size, |
| perf_buffer__process_record, cpu_buf); |
| if (ret != LIBBPF_PERF_EVENT_CONT) |
| return ret; |
| return 0; |
| } |
| |
| int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms) |
| { |
| int i, cnt, err; |
| |
| cnt = epoll_wait(pb->epoll_fd, pb->events, pb->cpu_cnt, timeout_ms); |
| for (i = 0; i < cnt; i++) { |
| struct perf_cpu_buf *cpu_buf = pb->events[i].data.ptr; |
| |
| err = perf_buffer__process_records(pb, cpu_buf); |
| if (err) { |
| pr_warning("error while processing records: %d\n", err); |
| return err; |
| } |
| } |
| return cnt < 0 ? -errno : cnt; |
| } |
| |
| struct bpf_prog_info_array_desc { |
| int array_offset; /* e.g. offset of jited_prog_insns */ |
| int count_offset; /* e.g. offset of jited_prog_len */ |
| int size_offset; /* > 0: offset of rec size, |
| * < 0: fix size of -size_offset |
| */ |
| }; |
| |
| static struct bpf_prog_info_array_desc bpf_prog_info_array_desc[] = { |
| [BPF_PROG_INFO_JITED_INSNS] = { |
| offsetof(struct bpf_prog_info, jited_prog_insns), |
| offsetof(struct bpf_prog_info, jited_prog_len), |
| -1, |
| }, |
| [BPF_PROG_INFO_XLATED_INSNS] = { |
| offsetof(struct bpf_prog_info, xlated_prog_insns), |
| offsetof(struct bpf_prog_info, xlated_prog_len), |
| -1, |
| }, |
| [BPF_PROG_INFO_MAP_IDS] = { |
| offsetof(struct bpf_prog_info, map_ids), |
| offsetof(struct bpf_prog_info, nr_map_ids), |
| -(int)sizeof(__u32), |
| }, |
| [BPF_PROG_INFO_JITED_KSYMS] = { |
| offsetof(struct bpf_prog_info, jited_ksyms), |
| offsetof(struct bpf_prog_info, nr_jited_ksyms), |
| -(int)sizeof(__u64), |
| }, |
| [BPF_PROG_INFO_JITED_FUNC_LENS] = { |
| offsetof(struct bpf_prog_info, jited_func_lens), |
| offsetof(struct bpf_prog_info, nr_jited_func_lens), |
| -(int)sizeof(__u32), |
| }, |
| [BPF_PROG_INFO_FUNC_INFO] = { |
| offsetof(struct bpf_prog_info, func_info), |
| offsetof(struct bpf_prog_info, nr_func_info), |
| offsetof(struct bpf_prog_info, func_info_rec_size), |
| }, |
| [BPF_PROG_INFO_LINE_INFO] = { |
| offsetof(struct bpf_prog_info, line_info), |
| offsetof(struct bpf_prog_info, nr_line_info), |
| offsetof(struct bpf_prog_info, line_info_rec_size), |
| }, |
| [BPF_PROG_INFO_JITED_LINE_INFO] = { |
| offsetof(struct bpf_prog_info, jited_line_info), |
| offsetof(struct bpf_prog_info, nr_jited_line_info), |
| offsetof(struct bpf_prog_info, jited_line_info_rec_size), |
| }, |
| [BPF_PROG_INFO_PROG_TAGS] = { |
| offsetof(struct bpf_prog_info, prog_tags), |
| offsetof(struct bpf_prog_info, nr_prog_tags), |
| -(int)sizeof(__u8) * BPF_TAG_SIZE, |
| }, |
| |
| }; |
| |
| static __u32 bpf_prog_info_read_offset_u32(struct bpf_prog_info *info, int offset) |
| { |
| __u32 *array = (__u32 *)info; |
| |
| if (offset >= 0) |
| return array[offset / sizeof(__u32)]; |
| return -(int)offset; |
| } |
| |
| static __u64 bpf_prog_info_read_offset_u64(struct bpf_prog_info *info, int offset) |
| { |
| __u64 *array = (__u64 *)info; |
| |
| if (offset >= 0) |
| return array[offset / sizeof(__u64)]; |
| return -(int)offset; |
| } |
| |
| static void bpf_prog_info_set_offset_u32(struct bpf_prog_info *info, int offset, |
| __u32 val) |
| { |
| __u32 *array = (__u32 *)info; |
| |
| if (offset >= 0) |
| array[offset / sizeof(__u32)] = val; |
| } |
| |
| static void bpf_prog_info_set_offset_u64(struct bpf_prog_info *info, int offset, |
| __u64 val) |
| { |
| __u64 *array = (__u64 *)info; |
| |
| if (offset >= 0) |
| array[offset / sizeof(__u64)] = val; |
| } |
| |
| struct bpf_prog_info_linear * |
| bpf_program__get_prog_info_linear(int fd, __u64 arrays) |
| { |
| struct bpf_prog_info_linear *info_linear; |
| struct bpf_prog_info info = {}; |
| __u32 info_len = sizeof(info); |
| __u32 data_len = 0; |
| int i, err; |
| void *ptr; |
| |
| if (arrays >> BPF_PROG_INFO_LAST_ARRAY) |
| return ERR_PTR(-EINVAL); |
| |
| /* step 1: get array dimensions */ |
| err = bpf_obj_get_info_by_fd(fd, &info, &info_len); |
| if (err) { |
| pr_debug("can't get prog info: %s", strerror(errno)); |
| return ERR_PTR(-EFAULT); |
| } |
| |
| /* step 2: calculate total size of all arrays */ |
| for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { |
| bool include_array = (arrays & (1UL << i)) > 0; |
| struct bpf_prog_info_array_desc *desc; |
| __u32 count, size; |
| |
| desc = bpf_prog_info_array_desc + i; |
| |
| /* kernel is too old to support this field */ |
| if (info_len < desc->array_offset + sizeof(__u32) || |
| info_len < desc->count_offset + sizeof(__u32) || |
| (desc->size_offset > 0 && info_len < desc->size_offset)) |
| include_array = false; |
| |
| if (!include_array) { |
| arrays &= ~(1UL << i); /* clear the bit */ |
| continue; |
| } |
| |
| count = bpf_prog_info_read_offset_u32(&info, desc->count_offset); |
| size = bpf_prog_info_read_offset_u32(&info, desc->size_offset); |
| |
| data_len += count * size; |
| } |
| |
| /* step 3: allocate continuous memory */ |
| data_len = roundup(data_len, sizeof(__u64)); |
| info_linear = malloc(sizeof(struct bpf_prog_info_linear) + data_len); |
| if (!info_linear) |
| return ERR_PTR(-ENOMEM); |
| |
| /* step 4: fill data to info_linear->info */ |
| info_linear->arrays = arrays; |
| memset(&info_linear->info, 0, sizeof(info)); |
| ptr = info_linear->data; |
| |
| for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { |
| struct bpf_prog_info_array_desc *desc; |
| __u32 count, size; |
| |
| if ((arrays & (1UL << i)) == 0) |
| continue; |
| |
| desc = bpf_prog_info_array_desc + i; |
| count = bpf_prog_info_read_offset_u32(&info, desc->count_offset); |
| size = bpf_prog_info_read_offset_u32(&info, desc->size_offset); |
| bpf_prog_info_set_offset_u32(&info_linear->info, |
| desc->count_offset, count); |
| bpf_prog_info_set_offset_u32(&info_linear->info, |
| desc->size_offset, size); |
| bpf_prog_info_set_offset_u64(&info_linear->info, |
| desc->array_offset, |
| ptr_to_u64(ptr)); |
| ptr += count * size; |
| } |
| |
| /* step 5: call syscall again to get required arrays */ |
| err = bpf_obj_get_info_by_fd(fd, &info_linear->info, &info_len); |
| if (err) { |
| pr_debug("can't get prog info: %s", strerror(errno)); |
| free(info_linear); |
| return ERR_PTR(-EFAULT); |
| } |
| |
| /* step 6: verify the data */ |
| for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { |
| struct bpf_prog_info_array_desc *desc; |
| __u32 v1, v2; |
| |
| if ((arrays & (1UL << i)) == 0) |
| continue; |
| |
| desc = bpf_prog_info_array_desc + i; |
| v1 = bpf_prog_info_read_offset_u32(&info, desc->count_offset); |
| v2 = bpf_prog_info_read_offset_u32(&info_linear->info, |
| desc->count_offset); |
| if (v1 != v2) |
| pr_warning("%s: mismatch in element count\n", __func__); |
| |
| v1 = bpf_prog_info_read_offset_u32(&info, desc->size_offset); |
| v2 = bpf_prog_info_read_offset_u32(&info_linear->info, |
| desc->size_offset); |
| if (v1 != v2) |
| pr_warning("%s: mismatch in rec size\n", __func__); |
| } |
| |
| /* step 7: update info_len and data_len */ |
| info_linear->info_len = sizeof(struct bpf_prog_info); |
| info_linear->data_len = data_len; |
| |
| return info_linear; |
| } |
| |
| void bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear) |
| { |
| int i; |
| |
| for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { |
| struct bpf_prog_info_array_desc *desc; |
| __u64 addr, offs; |
| |
| if ((info_linear->arrays & (1UL << i)) == 0) |
| continue; |
| |
| desc = bpf_prog_info_array_desc + i; |
| addr = bpf_prog_info_read_offset_u64(&info_linear->info, |
| desc->array_offset); |
| offs = addr - ptr_to_u64(info_linear->data); |
| bpf_prog_info_set_offset_u64(&info_linear->info, |
| desc->array_offset, offs); |
| } |
| } |
| |
| void bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear) |
| { |
| int i; |
| |
| for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { |
| struct bpf_prog_info_array_desc *desc; |
| __u64 addr, offs; |
| |
| if ((info_linear->arrays & (1UL << i)) == 0) |
| continue; |
| |
| desc = bpf_prog_info_array_desc + i; |
| offs = bpf_prog_info_read_offset_u64(&info_linear->info, |
| desc->array_offset); |
| addr = offs + ptr_to_u64(info_linear->data); |
| bpf_prog_info_set_offset_u64(&info_linear->info, |
| desc->array_offset, addr); |
| } |
| } |
| |
| int libbpf_num_possible_cpus(void) |
| { |
| static const char *fcpu = "/sys/devices/system/cpu/possible"; |
| int len = 0, n = 0, il = 0, ir = 0; |
| unsigned int start = 0, end = 0; |
| int tmp_cpus = 0; |
| static int cpus; |
| char buf[128]; |
| int error = 0; |
| int fd = -1; |
| |
| tmp_cpus = READ_ONCE(cpus); |
| if (tmp_cpus > 0) |
| return tmp_cpus; |
| |
| fd = open(fcpu, O_RDONLY); |
| if (fd < 0) { |
| error = errno; |
| pr_warning("Failed to open file %s: %s\n", |
| fcpu, strerror(error)); |
| return -error; |
| } |
| len = read(fd, buf, sizeof(buf)); |
| close(fd); |
| if (len <= 0) { |
| error = len ? errno : EINVAL; |
| pr_warning("Failed to read # of possible cpus from %s: %s\n", |
| fcpu, strerror(error)); |
| return -error; |
| } |
| if (len == sizeof(buf)) { |
| pr_warning("File %s size overflow\n", fcpu); |
| return -EOVERFLOW; |
| } |
| buf[len] = '\0'; |
| |
| for (ir = 0, tmp_cpus = 0; ir <= len; ir++) { |
| /* Each sub string separated by ',' has format \d+-\d+ or \d+ */ |
| if (buf[ir] == ',' || buf[ir] == '\0') { |
| buf[ir] = '\0'; |
| n = sscanf(&buf[il], "%u-%u", &start, &end); |
| if (n <= 0) { |
| pr_warning("Failed to get # CPUs from %s\n", |
| &buf[il]); |
| return -EINVAL; |
| } else if (n == 1) { |
| end = start; |
| } |
| tmp_cpus += end - start + 1; |
| il = ir + 1; |
| } |
| } |
| if (tmp_cpus <= 0) { |
| pr_warning("Invalid #CPUs %d from %s\n", tmp_cpus, fcpu); |
| return -EINVAL; |
| } |
| |
| WRITE_ONCE(cpus, tmp_cpus); |
| return tmp_cpus; |
| } |