| // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) |
| /* Copyright (C) 2019 Facebook */ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <linux/err.h> |
| #include <stdbool.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <unistd.h> |
| #include <linux/btf.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| |
| #include <bpf/bpf.h> |
| #include <bpf/btf.h> |
| #include <bpf/hashmap.h> |
| #include <bpf/libbpf.h> |
| |
| #include "json_writer.h" |
| #include "main.h" |
| |
| static const char * const btf_kind_str[NR_BTF_KINDS] = { |
| [BTF_KIND_UNKN] = "UNKNOWN", |
| [BTF_KIND_INT] = "INT", |
| [BTF_KIND_PTR] = "PTR", |
| [BTF_KIND_ARRAY] = "ARRAY", |
| [BTF_KIND_STRUCT] = "STRUCT", |
| [BTF_KIND_UNION] = "UNION", |
| [BTF_KIND_ENUM] = "ENUM", |
| [BTF_KIND_FWD] = "FWD", |
| [BTF_KIND_TYPEDEF] = "TYPEDEF", |
| [BTF_KIND_VOLATILE] = "VOLATILE", |
| [BTF_KIND_CONST] = "CONST", |
| [BTF_KIND_RESTRICT] = "RESTRICT", |
| [BTF_KIND_FUNC] = "FUNC", |
| [BTF_KIND_FUNC_PROTO] = "FUNC_PROTO", |
| [BTF_KIND_VAR] = "VAR", |
| [BTF_KIND_DATASEC] = "DATASEC", |
| [BTF_KIND_FLOAT] = "FLOAT", |
| [BTF_KIND_DECL_TAG] = "DECL_TAG", |
| [BTF_KIND_TYPE_TAG] = "TYPE_TAG", |
| [BTF_KIND_ENUM64] = "ENUM64", |
| }; |
| |
| struct btf_attach_point { |
| __u32 obj_id; |
| __u32 btf_id; |
| }; |
| |
| static const char *btf_int_enc_str(__u8 encoding) |
| { |
| switch (encoding) { |
| case 0: |
| return "(none)"; |
| case BTF_INT_SIGNED: |
| return "SIGNED"; |
| case BTF_INT_CHAR: |
| return "CHAR"; |
| case BTF_INT_BOOL: |
| return "BOOL"; |
| default: |
| return "UNKN"; |
| } |
| } |
| |
| static const char *btf_var_linkage_str(__u32 linkage) |
| { |
| switch (linkage) { |
| case BTF_VAR_STATIC: |
| return "static"; |
| case BTF_VAR_GLOBAL_ALLOCATED: |
| return "global"; |
| case BTF_VAR_GLOBAL_EXTERN: |
| return "extern"; |
| default: |
| return "(unknown)"; |
| } |
| } |
| |
| static const char *btf_func_linkage_str(const struct btf_type *t) |
| { |
| switch (btf_vlen(t)) { |
| case BTF_FUNC_STATIC: |
| return "static"; |
| case BTF_FUNC_GLOBAL: |
| return "global"; |
| case BTF_FUNC_EXTERN: |
| return "extern"; |
| default: |
| return "(unknown)"; |
| } |
| } |
| |
| static const char *btf_str(const struct btf *btf, __u32 off) |
| { |
| if (!off) |
| return "(anon)"; |
| return btf__name_by_offset(btf, off) ? : "(invalid)"; |
| } |
| |
| static int btf_kind_safe(int kind) |
| { |
| return kind <= BTF_KIND_MAX ? kind : BTF_KIND_UNKN; |
| } |
| |
| static int dump_btf_type(const struct btf *btf, __u32 id, |
| const struct btf_type *t) |
| { |
| json_writer_t *w = json_wtr; |
| int kind = btf_kind(t); |
| |
| if (json_output) { |
| jsonw_start_object(w); |
| jsonw_uint_field(w, "id", id); |
| jsonw_string_field(w, "kind", btf_kind_str[btf_kind_safe(kind)]); |
| jsonw_string_field(w, "name", btf_str(btf, t->name_off)); |
| } else { |
| printf("[%u] %s '%s'", id, btf_kind_str[btf_kind_safe(kind)], |
| btf_str(btf, t->name_off)); |
| } |
| |
| switch (kind) { |
| case BTF_KIND_INT: { |
| __u32 v = *(__u32 *)(t + 1); |
| const char *enc; |
| |
| enc = btf_int_enc_str(BTF_INT_ENCODING(v)); |
| |
| if (json_output) { |
| jsonw_uint_field(w, "size", t->size); |
| jsonw_uint_field(w, "bits_offset", BTF_INT_OFFSET(v)); |
| jsonw_uint_field(w, "nr_bits", BTF_INT_BITS(v)); |
| jsonw_string_field(w, "encoding", enc); |
| } else { |
| printf(" size=%u bits_offset=%u nr_bits=%u encoding=%s", |
| t->size, BTF_INT_OFFSET(v), BTF_INT_BITS(v), |
| enc); |
| } |
| break; |
| } |
| case BTF_KIND_PTR: |
| case BTF_KIND_CONST: |
| case BTF_KIND_VOLATILE: |
| case BTF_KIND_RESTRICT: |
| case BTF_KIND_TYPEDEF: |
| case BTF_KIND_TYPE_TAG: |
| if (json_output) |
| jsonw_uint_field(w, "type_id", t->type); |
| else |
| printf(" type_id=%u", t->type); |
| break; |
| case BTF_KIND_ARRAY: { |
| const struct btf_array *arr = (const void *)(t + 1); |
| |
| if (json_output) { |
| jsonw_uint_field(w, "type_id", arr->type); |
| jsonw_uint_field(w, "index_type_id", arr->index_type); |
| jsonw_uint_field(w, "nr_elems", arr->nelems); |
| } else { |
| printf(" type_id=%u index_type_id=%u nr_elems=%u", |
| arr->type, arr->index_type, arr->nelems); |
| } |
| break; |
| } |
| case BTF_KIND_STRUCT: |
| case BTF_KIND_UNION: { |
| const struct btf_member *m = (const void *)(t + 1); |
| __u16 vlen = BTF_INFO_VLEN(t->info); |
| int i; |
| |
| if (json_output) { |
| jsonw_uint_field(w, "size", t->size); |
| jsonw_uint_field(w, "vlen", vlen); |
| jsonw_name(w, "members"); |
| jsonw_start_array(w); |
| } else { |
| printf(" size=%u vlen=%u", t->size, vlen); |
| } |
| for (i = 0; i < vlen; i++, m++) { |
| const char *name = btf_str(btf, m->name_off); |
| __u32 bit_off, bit_sz; |
| |
| if (BTF_INFO_KFLAG(t->info)) { |
| bit_off = BTF_MEMBER_BIT_OFFSET(m->offset); |
| bit_sz = BTF_MEMBER_BITFIELD_SIZE(m->offset); |
| } else { |
| bit_off = m->offset; |
| bit_sz = 0; |
| } |
| |
| if (json_output) { |
| jsonw_start_object(w); |
| jsonw_string_field(w, "name", name); |
| jsonw_uint_field(w, "type_id", m->type); |
| jsonw_uint_field(w, "bits_offset", bit_off); |
| if (bit_sz) { |
| jsonw_uint_field(w, "bitfield_size", |
| bit_sz); |
| } |
| jsonw_end_object(w); |
| } else { |
| printf("\n\t'%s' type_id=%u bits_offset=%u", |
| name, m->type, bit_off); |
| if (bit_sz) |
| printf(" bitfield_size=%u", bit_sz); |
| } |
| } |
| if (json_output) |
| jsonw_end_array(w); |
| break; |
| } |
| case BTF_KIND_ENUM: { |
| const struct btf_enum *v = (const void *)(t + 1); |
| __u16 vlen = BTF_INFO_VLEN(t->info); |
| const char *encoding; |
| int i; |
| |
| encoding = btf_kflag(t) ? "SIGNED" : "UNSIGNED"; |
| if (json_output) { |
| jsonw_string_field(w, "encoding", encoding); |
| jsonw_uint_field(w, "size", t->size); |
| jsonw_uint_field(w, "vlen", vlen); |
| jsonw_name(w, "values"); |
| jsonw_start_array(w); |
| } else { |
| printf(" encoding=%s size=%u vlen=%u", encoding, t->size, vlen); |
| } |
| for (i = 0; i < vlen; i++, v++) { |
| const char *name = btf_str(btf, v->name_off); |
| |
| if (json_output) { |
| jsonw_start_object(w); |
| jsonw_string_field(w, "name", name); |
| if (btf_kflag(t)) |
| jsonw_int_field(w, "val", v->val); |
| else |
| jsonw_uint_field(w, "val", v->val); |
| jsonw_end_object(w); |
| } else { |
| if (btf_kflag(t)) |
| printf("\n\t'%s' val=%d", name, v->val); |
| else |
| printf("\n\t'%s' val=%u", name, v->val); |
| } |
| } |
| if (json_output) |
| jsonw_end_array(w); |
| break; |
| } |
| case BTF_KIND_ENUM64: { |
| const struct btf_enum64 *v = btf_enum64(t); |
| __u16 vlen = btf_vlen(t); |
| const char *encoding; |
| int i; |
| |
| encoding = btf_kflag(t) ? "SIGNED" : "UNSIGNED"; |
| if (json_output) { |
| jsonw_string_field(w, "encoding", encoding); |
| jsonw_uint_field(w, "size", t->size); |
| jsonw_uint_field(w, "vlen", vlen); |
| jsonw_name(w, "values"); |
| jsonw_start_array(w); |
| } else { |
| printf(" encoding=%s size=%u vlen=%u", encoding, t->size, vlen); |
| } |
| for (i = 0; i < vlen; i++, v++) { |
| const char *name = btf_str(btf, v->name_off); |
| __u64 val = ((__u64)v->val_hi32 << 32) | v->val_lo32; |
| |
| if (json_output) { |
| jsonw_start_object(w); |
| jsonw_string_field(w, "name", name); |
| if (btf_kflag(t)) |
| jsonw_int_field(w, "val", val); |
| else |
| jsonw_uint_field(w, "val", val); |
| jsonw_end_object(w); |
| } else { |
| if (btf_kflag(t)) |
| printf("\n\t'%s' val=%lldLL", name, |
| (unsigned long long)val); |
| else |
| printf("\n\t'%s' val=%lluULL", name, |
| (unsigned long long)val); |
| } |
| } |
| if (json_output) |
| jsonw_end_array(w); |
| break; |
| } |
| case BTF_KIND_FWD: { |
| const char *fwd_kind = BTF_INFO_KFLAG(t->info) ? "union" |
| : "struct"; |
| |
| if (json_output) |
| jsonw_string_field(w, "fwd_kind", fwd_kind); |
| else |
| printf(" fwd_kind=%s", fwd_kind); |
| break; |
| } |
| case BTF_KIND_FUNC: { |
| const char *linkage = btf_func_linkage_str(t); |
| |
| if (json_output) { |
| jsonw_uint_field(w, "type_id", t->type); |
| jsonw_string_field(w, "linkage", linkage); |
| } else { |
| printf(" type_id=%u linkage=%s", t->type, linkage); |
| } |
| break; |
| } |
| case BTF_KIND_FUNC_PROTO: { |
| const struct btf_param *p = (const void *)(t + 1); |
| __u16 vlen = BTF_INFO_VLEN(t->info); |
| int i; |
| |
| if (json_output) { |
| jsonw_uint_field(w, "ret_type_id", t->type); |
| jsonw_uint_field(w, "vlen", vlen); |
| jsonw_name(w, "params"); |
| jsonw_start_array(w); |
| } else { |
| printf(" ret_type_id=%u vlen=%u", t->type, vlen); |
| } |
| for (i = 0; i < vlen; i++, p++) { |
| const char *name = btf_str(btf, p->name_off); |
| |
| if (json_output) { |
| jsonw_start_object(w); |
| jsonw_string_field(w, "name", name); |
| jsonw_uint_field(w, "type_id", p->type); |
| jsonw_end_object(w); |
| } else { |
| printf("\n\t'%s' type_id=%u", name, p->type); |
| } |
| } |
| if (json_output) |
| jsonw_end_array(w); |
| break; |
| } |
| case BTF_KIND_VAR: { |
| const struct btf_var *v = (const void *)(t + 1); |
| const char *linkage; |
| |
| linkage = btf_var_linkage_str(v->linkage); |
| |
| if (json_output) { |
| jsonw_uint_field(w, "type_id", t->type); |
| jsonw_string_field(w, "linkage", linkage); |
| } else { |
| printf(" type_id=%u, linkage=%s", t->type, linkage); |
| } |
| break; |
| } |
| case BTF_KIND_DATASEC: { |
| const struct btf_var_secinfo *v = (const void *)(t + 1); |
| const struct btf_type *vt; |
| __u16 vlen = BTF_INFO_VLEN(t->info); |
| int i; |
| |
| if (json_output) { |
| jsonw_uint_field(w, "size", t->size); |
| jsonw_uint_field(w, "vlen", vlen); |
| jsonw_name(w, "vars"); |
| jsonw_start_array(w); |
| } else { |
| printf(" size=%u vlen=%u", t->size, vlen); |
| } |
| for (i = 0; i < vlen; i++, v++) { |
| if (json_output) { |
| jsonw_start_object(w); |
| jsonw_uint_field(w, "type_id", v->type); |
| jsonw_uint_field(w, "offset", v->offset); |
| jsonw_uint_field(w, "size", v->size); |
| jsonw_end_object(w); |
| } else { |
| printf("\n\ttype_id=%u offset=%u size=%u", |
| v->type, v->offset, v->size); |
| |
| if (v->type < btf__type_cnt(btf)) { |
| vt = btf__type_by_id(btf, v->type); |
| printf(" (%s '%s')", |
| btf_kind_str[btf_kind_safe(btf_kind(vt))], |
| btf_str(btf, vt->name_off)); |
| } |
| } |
| } |
| if (json_output) |
| jsonw_end_array(w); |
| break; |
| } |
| case BTF_KIND_FLOAT: { |
| if (json_output) |
| jsonw_uint_field(w, "size", t->size); |
| else |
| printf(" size=%u", t->size); |
| break; |
| } |
| case BTF_KIND_DECL_TAG: { |
| const struct btf_decl_tag *tag = (const void *)(t + 1); |
| |
| if (json_output) { |
| jsonw_uint_field(w, "type_id", t->type); |
| jsonw_int_field(w, "component_idx", tag->component_idx); |
| } else { |
| printf(" type_id=%u component_idx=%d", t->type, tag->component_idx); |
| } |
| break; |
| } |
| default: |
| break; |
| } |
| |
| if (json_output) |
| jsonw_end_object(json_wtr); |
| else |
| printf("\n"); |
| |
| return 0; |
| } |
| |
| static int dump_btf_raw(const struct btf *btf, |
| __u32 *root_type_ids, int root_type_cnt) |
| { |
| const struct btf_type *t; |
| int i; |
| |
| if (json_output) { |
| jsonw_start_object(json_wtr); |
| jsonw_name(json_wtr, "types"); |
| jsonw_start_array(json_wtr); |
| } |
| |
| if (root_type_cnt) { |
| for (i = 0; i < root_type_cnt; i++) { |
| t = btf__type_by_id(btf, root_type_ids[i]); |
| dump_btf_type(btf, root_type_ids[i], t); |
| } |
| } else { |
| const struct btf *base; |
| int cnt = btf__type_cnt(btf); |
| int start_id = 1; |
| |
| base = btf__base_btf(btf); |
| if (base) |
| start_id = btf__type_cnt(base); |
| |
| for (i = start_id; i < cnt; i++) { |
| t = btf__type_by_id(btf, i); |
| dump_btf_type(btf, i, t); |
| } |
| } |
| |
| if (json_output) { |
| jsonw_end_array(json_wtr); |
| jsonw_end_object(json_wtr); |
| } |
| return 0; |
| } |
| |
| static void __printf(2, 0) btf_dump_printf(void *ctx, |
| const char *fmt, va_list args) |
| { |
| vfprintf(stdout, fmt, args); |
| } |
| |
| static int dump_btf_c(const struct btf *btf, |
| __u32 *root_type_ids, int root_type_cnt) |
| { |
| struct btf_dump *d; |
| int err = 0, i; |
| |
| d = btf_dump__new(btf, btf_dump_printf, NULL, NULL); |
| err = libbpf_get_error(d); |
| if (err) |
| return err; |
| |
| printf("#ifndef __VMLINUX_H__\n"); |
| printf("#define __VMLINUX_H__\n"); |
| printf("\n"); |
| printf("#ifndef BPF_NO_PRESERVE_ACCESS_INDEX\n"); |
| printf("#pragma clang attribute push (__attribute__((preserve_access_index)), apply_to = record)\n"); |
| printf("#endif\n\n"); |
| |
| if (root_type_cnt) { |
| for (i = 0; i < root_type_cnt; i++) { |
| err = btf_dump__dump_type(d, root_type_ids[i]); |
| if (err) |
| goto done; |
| } |
| } else { |
| int cnt = btf__type_cnt(btf); |
| |
| for (i = 1; i < cnt; i++) { |
| err = btf_dump__dump_type(d, i); |
| if (err) |
| goto done; |
| } |
| } |
| |
| printf("#ifndef BPF_NO_PRESERVE_ACCESS_INDEX\n"); |
| printf("#pragma clang attribute pop\n"); |
| printf("#endif\n"); |
| printf("\n"); |
| printf("#endif /* __VMLINUX_H__ */\n"); |
| |
| done: |
| btf_dump__free(d); |
| return err; |
| } |
| |
| static const char sysfs_vmlinux[] = "/sys/kernel/btf/vmlinux"; |
| |
| static struct btf *get_vmlinux_btf_from_sysfs(void) |
| { |
| struct btf *base; |
| |
| base = btf__parse(sysfs_vmlinux, NULL); |
| if (libbpf_get_error(base)) { |
| p_err("failed to parse vmlinux BTF at '%s': %ld\n", |
| sysfs_vmlinux, libbpf_get_error(base)); |
| base = NULL; |
| } |
| |
| return base; |
| } |
| |
| #define BTF_NAME_BUFF_LEN 64 |
| |
| static bool btf_is_kernel_module(__u32 btf_id) |
| { |
| struct bpf_btf_info btf_info = {}; |
| char btf_name[BTF_NAME_BUFF_LEN]; |
| int btf_fd; |
| __u32 len; |
| int err; |
| |
| btf_fd = bpf_btf_get_fd_by_id(btf_id); |
| if (btf_fd < 0) { |
| p_err("can't get BTF object by id (%u): %s", btf_id, strerror(errno)); |
| return false; |
| } |
| |
| len = sizeof(btf_info); |
| btf_info.name = ptr_to_u64(btf_name); |
| btf_info.name_len = sizeof(btf_name); |
| err = bpf_obj_get_info_by_fd(btf_fd, &btf_info, &len); |
| close(btf_fd); |
| if (err) { |
| p_err("can't get BTF (ID %u) object info: %s", btf_id, strerror(errno)); |
| return false; |
| } |
| |
| return btf_info.kernel_btf && strncmp(btf_name, "vmlinux", sizeof(btf_name)) != 0; |
| } |
| |
| static int do_dump(int argc, char **argv) |
| { |
| struct btf *btf = NULL, *base = NULL; |
| __u32 root_type_ids[2]; |
| int root_type_cnt = 0; |
| bool dump_c = false; |
| __u32 btf_id = -1; |
| const char *src; |
| int fd = -1; |
| int err; |
| |
| if (!REQ_ARGS(2)) { |
| usage(); |
| return -1; |
| } |
| src = GET_ARG(); |
| if (is_prefix(src, "map")) { |
| struct bpf_map_info info = {}; |
| __u32 len = sizeof(info); |
| |
| if (!REQ_ARGS(2)) { |
| usage(); |
| return -1; |
| } |
| |
| fd = map_parse_fd_and_info(&argc, &argv, &info, &len); |
| if (fd < 0) |
| return -1; |
| |
| btf_id = info.btf_id; |
| if (argc && is_prefix(*argv, "key")) { |
| root_type_ids[root_type_cnt++] = info.btf_key_type_id; |
| NEXT_ARG(); |
| } else if (argc && is_prefix(*argv, "value")) { |
| root_type_ids[root_type_cnt++] = info.btf_value_type_id; |
| NEXT_ARG(); |
| } else if (argc && is_prefix(*argv, "all")) { |
| NEXT_ARG(); |
| } else if (argc && is_prefix(*argv, "kv")) { |
| root_type_ids[root_type_cnt++] = info.btf_key_type_id; |
| root_type_ids[root_type_cnt++] = info.btf_value_type_id; |
| NEXT_ARG(); |
| } else { |
| root_type_ids[root_type_cnt++] = info.btf_key_type_id; |
| root_type_ids[root_type_cnt++] = info.btf_value_type_id; |
| } |
| } else if (is_prefix(src, "prog")) { |
| struct bpf_prog_info info = {}; |
| __u32 len = sizeof(info); |
| |
| if (!REQ_ARGS(2)) { |
| usage(); |
| return -1; |
| } |
| |
| fd = prog_parse_fd(&argc, &argv); |
| if (fd < 0) |
| return -1; |
| |
| err = bpf_obj_get_info_by_fd(fd, &info, &len); |
| if (err) { |
| p_err("can't get prog info: %s", strerror(errno)); |
| goto done; |
| } |
| |
| btf_id = info.btf_id; |
| } else if (is_prefix(src, "id")) { |
| char *endptr; |
| |
| btf_id = strtoul(*argv, &endptr, 0); |
| if (*endptr) { |
| p_err("can't parse %s as ID", *argv); |
| return -1; |
| } |
| NEXT_ARG(); |
| } else if (is_prefix(src, "file")) { |
| const char sysfs_prefix[] = "/sys/kernel/btf/"; |
| |
| if (!base_btf && |
| strncmp(*argv, sysfs_prefix, sizeof(sysfs_prefix) - 1) == 0 && |
| strcmp(*argv, sysfs_vmlinux) != 0) |
| base = get_vmlinux_btf_from_sysfs(); |
| |
| btf = btf__parse_split(*argv, base ?: base_btf); |
| err = libbpf_get_error(btf); |
| if (err) { |
| btf = NULL; |
| p_err("failed to load BTF from %s: %s", |
| *argv, strerror(err)); |
| goto done; |
| } |
| NEXT_ARG(); |
| } else { |
| err = -1; |
| p_err("unrecognized BTF source specifier: '%s'", src); |
| goto done; |
| } |
| |
| while (argc) { |
| if (is_prefix(*argv, "format")) { |
| NEXT_ARG(); |
| if (argc < 1) { |
| p_err("expecting value for 'format' option\n"); |
| err = -EINVAL; |
| goto done; |
| } |
| if (strcmp(*argv, "c") == 0) { |
| dump_c = true; |
| } else if (strcmp(*argv, "raw") == 0) { |
| dump_c = false; |
| } else { |
| p_err("unrecognized format specifier: '%s', possible values: raw, c", |
| *argv); |
| err = -EINVAL; |
| goto done; |
| } |
| NEXT_ARG(); |
| } else { |
| p_err("unrecognized option: '%s'", *argv); |
| err = -EINVAL; |
| goto done; |
| } |
| } |
| |
| if (!btf) { |
| if (!base_btf && btf_is_kernel_module(btf_id)) { |
| p_info("Warning: valid base BTF was not specified with -B option, falling back to standard base BTF (%s)", |
| sysfs_vmlinux); |
| base_btf = get_vmlinux_btf_from_sysfs(); |
| } |
| |
| btf = btf__load_from_kernel_by_id_split(btf_id, base_btf); |
| err = libbpf_get_error(btf); |
| if (err) { |
| p_err("get btf by id (%u): %s", btf_id, strerror(err)); |
| goto done; |
| } |
| } |
| |
| if (dump_c) { |
| if (json_output) { |
| p_err("JSON output for C-syntax dump is not supported"); |
| err = -ENOTSUP; |
| goto done; |
| } |
| err = dump_btf_c(btf, root_type_ids, root_type_cnt); |
| } else { |
| err = dump_btf_raw(btf, root_type_ids, root_type_cnt); |
| } |
| |
| done: |
| close(fd); |
| btf__free(btf); |
| btf__free(base); |
| return err; |
| } |
| |
| static int btf_parse_fd(int *argc, char ***argv) |
| { |
| unsigned int id; |
| char *endptr; |
| int fd; |
| |
| if (!is_prefix(*argv[0], "id")) { |
| p_err("expected 'id', got: '%s'?", **argv); |
| return -1; |
| } |
| NEXT_ARGP(); |
| |
| id = strtoul(**argv, &endptr, 0); |
| if (*endptr) { |
| p_err("can't parse %s as ID", **argv); |
| return -1; |
| } |
| NEXT_ARGP(); |
| |
| fd = bpf_btf_get_fd_by_id(id); |
| if (fd < 0) |
| p_err("can't get BTF object by id (%u): %s", |
| id, strerror(errno)); |
| |
| return fd; |
| } |
| |
| static int |
| build_btf_type_table(struct hashmap *tab, enum bpf_obj_type type, |
| void *info, __u32 *len) |
| { |
| static const char * const names[] = { |
| [BPF_OBJ_UNKNOWN] = "unknown", |
| [BPF_OBJ_PROG] = "prog", |
| [BPF_OBJ_MAP] = "map", |
| }; |
| __u32 btf_id, id = 0; |
| int err; |
| int fd; |
| |
| while (true) { |
| switch (type) { |
| case BPF_OBJ_PROG: |
| err = bpf_prog_get_next_id(id, &id); |
| break; |
| case BPF_OBJ_MAP: |
| err = bpf_map_get_next_id(id, &id); |
| break; |
| default: |
| err = -1; |
| p_err("unexpected object type: %d", type); |
| goto err_free; |
| } |
| if (err) { |
| if (errno == ENOENT) { |
| err = 0; |
| break; |
| } |
| p_err("can't get next %s: %s%s", names[type], |
| strerror(errno), |
| errno == EINVAL ? " -- kernel too old?" : ""); |
| goto err_free; |
| } |
| |
| switch (type) { |
| case BPF_OBJ_PROG: |
| fd = bpf_prog_get_fd_by_id(id); |
| break; |
| case BPF_OBJ_MAP: |
| fd = bpf_map_get_fd_by_id(id); |
| break; |
| default: |
| err = -1; |
| p_err("unexpected object type: %d", type); |
| goto err_free; |
| } |
| if (fd < 0) { |
| if (errno == ENOENT) |
| continue; |
| p_err("can't get %s by id (%u): %s", names[type], id, |
| strerror(errno)); |
| err = -1; |
| goto err_free; |
| } |
| |
| memset(info, 0, *len); |
| err = bpf_obj_get_info_by_fd(fd, info, len); |
| close(fd); |
| if (err) { |
| p_err("can't get %s info: %s", names[type], |
| strerror(errno)); |
| goto err_free; |
| } |
| |
| switch (type) { |
| case BPF_OBJ_PROG: |
| btf_id = ((struct bpf_prog_info *)info)->btf_id; |
| break; |
| case BPF_OBJ_MAP: |
| btf_id = ((struct bpf_map_info *)info)->btf_id; |
| break; |
| default: |
| err = -1; |
| p_err("unexpected object type: %d", type); |
| goto err_free; |
| } |
| if (!btf_id) |
| continue; |
| |
| err = hashmap__append(tab, u32_as_hash_field(btf_id), |
| u32_as_hash_field(id)); |
| if (err) { |
| p_err("failed to append entry to hashmap for BTF ID %u, object ID %u: %s", |
| btf_id, id, strerror(errno)); |
| goto err_free; |
| } |
| } |
| |
| return 0; |
| |
| err_free: |
| hashmap__free(tab); |
| return err; |
| } |
| |
| static int |
| build_btf_tables(struct hashmap *btf_prog_table, |
| struct hashmap *btf_map_table) |
| { |
| struct bpf_prog_info prog_info; |
| __u32 prog_len = sizeof(prog_info); |
| struct bpf_map_info map_info; |
| __u32 map_len = sizeof(map_info); |
| int err = 0; |
| |
| err = build_btf_type_table(btf_prog_table, BPF_OBJ_PROG, &prog_info, |
| &prog_len); |
| if (err) |
| return err; |
| |
| err = build_btf_type_table(btf_map_table, BPF_OBJ_MAP, &map_info, |
| &map_len); |
| if (err) { |
| hashmap__free(btf_prog_table); |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| static void |
| show_btf_plain(struct bpf_btf_info *info, int fd, |
| struct hashmap *btf_prog_table, |
| struct hashmap *btf_map_table) |
| { |
| struct hashmap_entry *entry; |
| const char *name = u64_to_ptr(info->name); |
| int n; |
| |
| printf("%u: ", info->id); |
| if (info->kernel_btf) |
| printf("name [%s] ", name); |
| else if (name && name[0]) |
| printf("name %s ", name); |
| else |
| printf("name <anon> "); |
| printf("size %uB", info->btf_size); |
| |
| n = 0; |
| hashmap__for_each_key_entry(btf_prog_table, entry, |
| u32_as_hash_field(info->id)) { |
| printf("%s%u", n++ == 0 ? " prog_ids " : ",", |
| hash_field_as_u32(entry->value)); |
| } |
| |
| n = 0; |
| hashmap__for_each_key_entry(btf_map_table, entry, |
| u32_as_hash_field(info->id)) { |
| printf("%s%u", n++ == 0 ? " map_ids " : ",", |
| hash_field_as_u32(entry->value)); |
| } |
| |
| emit_obj_refs_plain(refs_table, info->id, "\n\tpids "); |
| |
| printf("\n"); |
| } |
| |
| static void |
| show_btf_json(struct bpf_btf_info *info, int fd, |
| struct hashmap *btf_prog_table, |
| struct hashmap *btf_map_table) |
| { |
| struct hashmap_entry *entry; |
| const char *name = u64_to_ptr(info->name); |
| |
| jsonw_start_object(json_wtr); /* btf object */ |
| jsonw_uint_field(json_wtr, "id", info->id); |
| jsonw_uint_field(json_wtr, "size", info->btf_size); |
| |
| jsonw_name(json_wtr, "prog_ids"); |
| jsonw_start_array(json_wtr); /* prog_ids */ |
| hashmap__for_each_key_entry(btf_prog_table, entry, |
| u32_as_hash_field(info->id)) { |
| jsonw_uint(json_wtr, hash_field_as_u32(entry->value)); |
| } |
| jsonw_end_array(json_wtr); /* prog_ids */ |
| |
| jsonw_name(json_wtr, "map_ids"); |
| jsonw_start_array(json_wtr); /* map_ids */ |
| hashmap__for_each_key_entry(btf_map_table, entry, |
| u32_as_hash_field(info->id)) { |
| jsonw_uint(json_wtr, hash_field_as_u32(entry->value)); |
| } |
| jsonw_end_array(json_wtr); /* map_ids */ |
| |
| emit_obj_refs_json(refs_table, info->id, json_wtr); /* pids */ |
| |
| jsonw_bool_field(json_wtr, "kernel", info->kernel_btf); |
| |
| if (name && name[0]) |
| jsonw_string_field(json_wtr, "name", name); |
| |
| jsonw_end_object(json_wtr); /* btf object */ |
| } |
| |
| static int |
| show_btf(int fd, struct hashmap *btf_prog_table, |
| struct hashmap *btf_map_table) |
| { |
| struct bpf_btf_info info; |
| __u32 len = sizeof(info); |
| char name[64]; |
| int err; |
| |
| memset(&info, 0, sizeof(info)); |
| err = bpf_obj_get_info_by_fd(fd, &info, &len); |
| if (err) { |
| p_err("can't get BTF object info: %s", strerror(errno)); |
| return -1; |
| } |
| /* if kernel support emitting BTF object name, pass name pointer */ |
| if (info.name_len) { |
| memset(&info, 0, sizeof(info)); |
| info.name_len = sizeof(name); |
| info.name = ptr_to_u64(name); |
| len = sizeof(info); |
| |
| err = bpf_obj_get_info_by_fd(fd, &info, &len); |
| if (err) { |
| p_err("can't get BTF object info: %s", strerror(errno)); |
| return -1; |
| } |
| } |
| |
| if (json_output) |
| show_btf_json(&info, fd, btf_prog_table, btf_map_table); |
| else |
| show_btf_plain(&info, fd, btf_prog_table, btf_map_table); |
| |
| return 0; |
| } |
| |
| static int do_show(int argc, char **argv) |
| { |
| struct hashmap *btf_prog_table; |
| struct hashmap *btf_map_table; |
| int err, fd = -1; |
| __u32 id = 0; |
| |
| if (argc == 2) { |
| fd = btf_parse_fd(&argc, &argv); |
| if (fd < 0) |
| return -1; |
| } |
| |
| if (argc) { |
| if (fd >= 0) |
| close(fd); |
| return BAD_ARG(); |
| } |
| |
| btf_prog_table = hashmap__new(hash_fn_for_key_as_id, |
| equal_fn_for_key_as_id, NULL); |
| btf_map_table = hashmap__new(hash_fn_for_key_as_id, |
| equal_fn_for_key_as_id, NULL); |
| if (IS_ERR(btf_prog_table) || IS_ERR(btf_map_table)) { |
| hashmap__free(btf_prog_table); |
| hashmap__free(btf_map_table); |
| if (fd >= 0) |
| close(fd); |
| p_err("failed to create hashmap for object references"); |
| return -1; |
| } |
| err = build_btf_tables(btf_prog_table, btf_map_table); |
| if (err) { |
| if (fd >= 0) |
| close(fd); |
| return err; |
| } |
| build_obj_refs_table(&refs_table, BPF_OBJ_BTF); |
| |
| if (fd >= 0) { |
| err = show_btf(fd, btf_prog_table, btf_map_table); |
| close(fd); |
| goto exit_free; |
| } |
| |
| if (json_output) |
| jsonw_start_array(json_wtr); /* root array */ |
| |
| while (true) { |
| err = bpf_btf_get_next_id(id, &id); |
| if (err) { |
| if (errno == ENOENT) { |
| err = 0; |
| break; |
| } |
| p_err("can't get next BTF object: %s%s", |
| strerror(errno), |
| errno == EINVAL ? " -- kernel too old?" : ""); |
| err = -1; |
| break; |
| } |
| |
| fd = bpf_btf_get_fd_by_id(id); |
| if (fd < 0) { |
| if (errno == ENOENT) |
| continue; |
| p_err("can't get BTF object by id (%u): %s", |
| id, strerror(errno)); |
| err = -1; |
| break; |
| } |
| |
| err = show_btf(fd, btf_prog_table, btf_map_table); |
| close(fd); |
| if (err) |
| break; |
| } |
| |
| if (json_output) |
| jsonw_end_array(json_wtr); /* root array */ |
| |
| exit_free: |
| hashmap__free(btf_prog_table); |
| hashmap__free(btf_map_table); |
| delete_obj_refs_table(refs_table); |
| |
| return err; |
| } |
| |
| static int do_help(int argc, char **argv) |
| { |
| if (json_output) { |
| jsonw_null(json_wtr); |
| return 0; |
| } |
| |
| fprintf(stderr, |
| "Usage: %1$s %2$s { show | list } [id BTF_ID]\n" |
| " %1$s %2$s dump BTF_SRC [format FORMAT]\n" |
| " %1$s %2$s help\n" |
| "\n" |
| " BTF_SRC := { id BTF_ID | prog PROG | map MAP [{key | value | kv | all}] | file FILE }\n" |
| " FORMAT := { raw | c }\n" |
| " " HELP_SPEC_MAP "\n" |
| " " HELP_SPEC_PROGRAM "\n" |
| " " HELP_SPEC_OPTIONS " |\n" |
| " {-B|--base-btf} }\n" |
| "", |
| bin_name, "btf"); |
| |
| return 0; |
| } |
| |
| static const struct cmd cmds[] = { |
| { "show", do_show }, |
| { "list", do_show }, |
| { "help", do_help }, |
| { "dump", do_dump }, |
| { 0 } |
| }; |
| |
| int do_btf(int argc, char **argv) |
| { |
| return cmd_select(cmds, argc, argv, do_help); |
| } |