| // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) |
| /* Copyright (c) 2018 Facebook */ |
| |
| #include <ctype.h> |
| #include <stdio.h> /* for (FILE *) used by json_writer */ |
| #include <string.h> |
| #include <asm/byteorder.h> |
| #include <linux/bitops.h> |
| #include <linux/btf.h> |
| #include <linux/err.h> |
| |
| #include "btf.h" |
| #include "json_writer.h" |
| #include "main.h" |
| |
| #define BITS_PER_BYTE_MASK (BITS_PER_BYTE - 1) |
| #define BITS_PER_BYTE_MASKED(bits) ((bits) & BITS_PER_BYTE_MASK) |
| #define BITS_ROUNDDOWN_BYTES(bits) ((bits) >> 3) |
| #define BITS_ROUNDUP_BYTES(bits) \ |
| (BITS_ROUNDDOWN_BYTES(bits) + !!BITS_PER_BYTE_MASKED(bits)) |
| |
| static int btf_dumper_do_type(const struct btf_dumper *d, __u32 type_id, |
| __u8 bit_offset, const void *data); |
| |
| static void btf_dumper_ptr(const void *data, json_writer_t *jw, |
| bool is_plain_text) |
| { |
| if (is_plain_text) |
| jsonw_printf(jw, "%p", *(void **)data); |
| else |
| jsonw_printf(jw, "%lu", *(unsigned long *)data); |
| } |
| |
| static int btf_dumper_modifier(const struct btf_dumper *d, __u32 type_id, |
| __u8 bit_offset, const void *data) |
| { |
| int actual_type_id; |
| |
| actual_type_id = btf__resolve_type(d->btf, type_id); |
| if (actual_type_id < 0) |
| return actual_type_id; |
| |
| return btf_dumper_do_type(d, actual_type_id, bit_offset, data); |
| } |
| |
| static void btf_dumper_enum(const void *data, json_writer_t *jw) |
| { |
| jsonw_printf(jw, "%d", *(int *)data); |
| } |
| |
| static int btf_dumper_array(const struct btf_dumper *d, __u32 type_id, |
| const void *data) |
| { |
| const struct btf_type *t = btf__type_by_id(d->btf, type_id); |
| struct btf_array *arr = (struct btf_array *)(t + 1); |
| long long elem_size; |
| int ret = 0; |
| __u32 i; |
| |
| elem_size = btf__resolve_size(d->btf, arr->type); |
| if (elem_size < 0) |
| return elem_size; |
| |
| jsonw_start_array(d->jw); |
| for (i = 0; i < arr->nelems; i++) { |
| ret = btf_dumper_do_type(d, arr->type, 0, |
| data + i * elem_size); |
| if (ret) |
| break; |
| } |
| |
| jsonw_end_array(d->jw); |
| return ret; |
| } |
| |
| static void btf_int128_print(json_writer_t *jw, const void *data, |
| bool is_plain_text) |
| { |
| /* data points to a __int128 number. |
| * Suppose |
| * int128_num = *(__int128 *)data; |
| * The below formulas shows what upper_num and lower_num represents: |
| * upper_num = int128_num >> 64; |
| * lower_num = int128_num & 0xffffffffFFFFFFFFULL; |
| */ |
| __u64 upper_num, lower_num; |
| |
| #ifdef __BIG_ENDIAN_BITFIELD |
| upper_num = *(__u64 *)data; |
| lower_num = *(__u64 *)(data + 8); |
| #else |
| upper_num = *(__u64 *)(data + 8); |
| lower_num = *(__u64 *)data; |
| #endif |
| |
| if (is_plain_text) { |
| if (upper_num == 0) |
| jsonw_printf(jw, "0x%llx", lower_num); |
| else |
| jsonw_printf(jw, "0x%llx%016llx", upper_num, lower_num); |
| } else { |
| if (upper_num == 0) |
| jsonw_printf(jw, "\"0x%llx\"", lower_num); |
| else |
| jsonw_printf(jw, "\"0x%llx%016llx\"", upper_num, lower_num); |
| } |
| } |
| |
| static void btf_int128_shift(__u64 *print_num, u16 left_shift_bits, |
| u16 right_shift_bits) |
| { |
| __u64 upper_num, lower_num; |
| |
| #ifdef __BIG_ENDIAN_BITFIELD |
| upper_num = print_num[0]; |
| lower_num = print_num[1]; |
| #else |
| upper_num = print_num[1]; |
| lower_num = print_num[0]; |
| #endif |
| |
| /* shake out un-needed bits by shift/or operations */ |
| if (left_shift_bits >= 64) { |
| upper_num = lower_num << (left_shift_bits - 64); |
| lower_num = 0; |
| } else { |
| upper_num = (upper_num << left_shift_bits) | |
| (lower_num >> (64 - left_shift_bits)); |
| lower_num = lower_num << left_shift_bits; |
| } |
| |
| if (right_shift_bits >= 64) { |
| lower_num = upper_num >> (right_shift_bits - 64); |
| upper_num = 0; |
| } else { |
| lower_num = (lower_num >> right_shift_bits) | |
| (upper_num << (64 - right_shift_bits)); |
| upper_num = upper_num >> right_shift_bits; |
| } |
| |
| #ifdef __BIG_ENDIAN_BITFIELD |
| print_num[0] = upper_num; |
| print_num[1] = lower_num; |
| #else |
| print_num[0] = lower_num; |
| print_num[1] = upper_num; |
| #endif |
| } |
| |
| static void btf_dumper_bitfield(__u32 nr_bits, __u8 bit_offset, |
| const void *data, json_writer_t *jw, |
| bool is_plain_text) |
| { |
| int left_shift_bits, right_shift_bits; |
| __u64 print_num[2] = {}; |
| int bytes_to_copy; |
| int bits_to_copy; |
| |
| bits_to_copy = bit_offset + nr_bits; |
| bytes_to_copy = BITS_ROUNDUP_BYTES(bits_to_copy); |
| |
| memcpy(print_num, data, bytes_to_copy); |
| #if defined(__BIG_ENDIAN_BITFIELD) |
| left_shift_bits = bit_offset; |
| #elif defined(__LITTLE_ENDIAN_BITFIELD) |
| left_shift_bits = 128 - bits_to_copy; |
| #else |
| #error neither big nor little endian |
| #endif |
| right_shift_bits = 128 - nr_bits; |
| |
| btf_int128_shift(print_num, left_shift_bits, right_shift_bits); |
| btf_int128_print(jw, print_num, is_plain_text); |
| } |
| |
| |
| static void btf_dumper_int_bits(__u32 int_type, __u8 bit_offset, |
| const void *data, json_writer_t *jw, |
| bool is_plain_text) |
| { |
| int nr_bits = BTF_INT_BITS(int_type); |
| int total_bits_offset; |
| |
| /* bits_offset is at most 7. |
| * BTF_INT_OFFSET() cannot exceed 128 bits. |
| */ |
| total_bits_offset = bit_offset + BTF_INT_OFFSET(int_type); |
| data += BITS_ROUNDDOWN_BYTES(total_bits_offset); |
| bit_offset = BITS_PER_BYTE_MASKED(total_bits_offset); |
| btf_dumper_bitfield(nr_bits, bit_offset, data, jw, |
| is_plain_text); |
| } |
| |
| static int btf_dumper_int(const struct btf_type *t, __u8 bit_offset, |
| const void *data, json_writer_t *jw, |
| bool is_plain_text) |
| { |
| __u32 *int_type; |
| __u32 nr_bits; |
| |
| int_type = (__u32 *)(t + 1); |
| nr_bits = BTF_INT_BITS(*int_type); |
| /* if this is bit field */ |
| if (bit_offset || BTF_INT_OFFSET(*int_type) || |
| BITS_PER_BYTE_MASKED(nr_bits)) { |
| btf_dumper_int_bits(*int_type, bit_offset, data, jw, |
| is_plain_text); |
| return 0; |
| } |
| |
| if (nr_bits == 128) { |
| btf_int128_print(jw, data, is_plain_text); |
| return 0; |
| } |
| |
| switch (BTF_INT_ENCODING(*int_type)) { |
| case 0: |
| if (BTF_INT_BITS(*int_type) == 64) |
| jsonw_printf(jw, "%llu", *(__u64 *)data); |
| else if (BTF_INT_BITS(*int_type) == 32) |
| jsonw_printf(jw, "%u", *(__u32 *)data); |
| else if (BTF_INT_BITS(*int_type) == 16) |
| jsonw_printf(jw, "%hu", *(__u16 *)data); |
| else if (BTF_INT_BITS(*int_type) == 8) |
| jsonw_printf(jw, "%hhu", *(__u8 *)data); |
| else |
| btf_dumper_int_bits(*int_type, bit_offset, data, jw, |
| is_plain_text); |
| break; |
| case BTF_INT_SIGNED: |
| if (BTF_INT_BITS(*int_type) == 64) |
| jsonw_printf(jw, "%lld", *(long long *)data); |
| else if (BTF_INT_BITS(*int_type) == 32) |
| jsonw_printf(jw, "%d", *(int *)data); |
| else if (BTF_INT_BITS(*int_type) == 16) |
| jsonw_printf(jw, "%hd", *(short *)data); |
| else if (BTF_INT_BITS(*int_type) == 8) |
| jsonw_printf(jw, "%hhd", *(char *)data); |
| else |
| btf_dumper_int_bits(*int_type, bit_offset, data, jw, |
| is_plain_text); |
| break; |
| case BTF_INT_CHAR: |
| if (isprint(*(char *)data)) |
| jsonw_printf(jw, "\"%c\"", *(char *)data); |
| else |
| if (is_plain_text) |
| jsonw_printf(jw, "0x%hhx", *(char *)data); |
| else |
| jsonw_printf(jw, "\"\\u00%02hhx\"", |
| *(char *)data); |
| break; |
| case BTF_INT_BOOL: |
| jsonw_bool(jw, *(int *)data); |
| break; |
| default: |
| /* shouldn't happen */ |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| static int btf_dumper_struct(const struct btf_dumper *d, __u32 type_id, |
| const void *data) |
| { |
| const struct btf_type *t; |
| struct btf_member *m; |
| const void *data_off; |
| int kind_flag; |
| int ret = 0; |
| int i, vlen; |
| |
| t = btf__type_by_id(d->btf, type_id); |
| if (!t) |
| return -EINVAL; |
| |
| kind_flag = BTF_INFO_KFLAG(t->info); |
| vlen = BTF_INFO_VLEN(t->info); |
| jsonw_start_object(d->jw); |
| m = (struct btf_member *)(t + 1); |
| |
| for (i = 0; i < vlen; i++) { |
| __u32 bit_offset = m[i].offset; |
| __u32 bitfield_size = 0; |
| |
| if (kind_flag) { |
| bitfield_size = BTF_MEMBER_BITFIELD_SIZE(bit_offset); |
| bit_offset = BTF_MEMBER_BIT_OFFSET(bit_offset); |
| } |
| |
| jsonw_name(d->jw, btf__name_by_offset(d->btf, m[i].name_off)); |
| data_off = data + BITS_ROUNDDOWN_BYTES(bit_offset); |
| if (bitfield_size) { |
| btf_dumper_bitfield(bitfield_size, |
| BITS_PER_BYTE_MASKED(bit_offset), |
| data_off, d->jw, d->is_plain_text); |
| } else { |
| ret = btf_dumper_do_type(d, m[i].type, |
| BITS_PER_BYTE_MASKED(bit_offset), |
| data_off); |
| if (ret) |
| break; |
| } |
| } |
| |
| jsonw_end_object(d->jw); |
| |
| return ret; |
| } |
| |
| static int btf_dumper_var(const struct btf_dumper *d, __u32 type_id, |
| __u8 bit_offset, const void *data) |
| { |
| const struct btf_type *t = btf__type_by_id(d->btf, type_id); |
| int ret; |
| |
| jsonw_start_object(d->jw); |
| jsonw_name(d->jw, btf__name_by_offset(d->btf, t->name_off)); |
| ret = btf_dumper_do_type(d, t->type, bit_offset, data); |
| jsonw_end_object(d->jw); |
| |
| return ret; |
| } |
| |
| static int btf_dumper_datasec(const struct btf_dumper *d, __u32 type_id, |
| const void *data) |
| { |
| struct btf_var_secinfo *vsi; |
| const struct btf_type *t; |
| int ret = 0, i, vlen; |
| |
| t = btf__type_by_id(d->btf, type_id); |
| if (!t) |
| return -EINVAL; |
| |
| vlen = BTF_INFO_VLEN(t->info); |
| vsi = (struct btf_var_secinfo *)(t + 1); |
| |
| jsonw_start_object(d->jw); |
| jsonw_name(d->jw, btf__name_by_offset(d->btf, t->name_off)); |
| jsonw_start_array(d->jw); |
| for (i = 0; i < vlen; i++) { |
| ret = btf_dumper_do_type(d, vsi[i].type, 0, data + vsi[i].offset); |
| if (ret) |
| break; |
| } |
| jsonw_end_array(d->jw); |
| jsonw_end_object(d->jw); |
| |
| return ret; |
| } |
| |
| static int btf_dumper_do_type(const struct btf_dumper *d, __u32 type_id, |
| __u8 bit_offset, const void *data) |
| { |
| const struct btf_type *t = btf__type_by_id(d->btf, type_id); |
| |
| switch (BTF_INFO_KIND(t->info)) { |
| case BTF_KIND_INT: |
| return btf_dumper_int(t, bit_offset, data, d->jw, |
| d->is_plain_text); |
| case BTF_KIND_STRUCT: |
| case BTF_KIND_UNION: |
| return btf_dumper_struct(d, type_id, data); |
| case BTF_KIND_ARRAY: |
| return btf_dumper_array(d, type_id, data); |
| case BTF_KIND_ENUM: |
| btf_dumper_enum(data, d->jw); |
| return 0; |
| case BTF_KIND_PTR: |
| btf_dumper_ptr(data, d->jw, d->is_plain_text); |
| return 0; |
| case BTF_KIND_UNKN: |
| jsonw_printf(d->jw, "(unknown)"); |
| return 0; |
| case BTF_KIND_FWD: |
| /* map key or value can't be forward */ |
| jsonw_printf(d->jw, "(fwd-kind-invalid)"); |
| return -EINVAL; |
| case BTF_KIND_TYPEDEF: |
| case BTF_KIND_VOLATILE: |
| case BTF_KIND_CONST: |
| case BTF_KIND_RESTRICT: |
| return btf_dumper_modifier(d, type_id, bit_offset, data); |
| case BTF_KIND_VAR: |
| return btf_dumper_var(d, type_id, bit_offset, data); |
| case BTF_KIND_DATASEC: |
| return btf_dumper_datasec(d, type_id, data); |
| default: |
| jsonw_printf(d->jw, "(unsupported-kind"); |
| return -EINVAL; |
| } |
| } |
| |
| int btf_dumper_type(const struct btf_dumper *d, __u32 type_id, |
| const void *data) |
| { |
| return btf_dumper_do_type(d, type_id, 0, data); |
| } |
| |
| #define BTF_PRINT_ARG(...) \ |
| do { \ |
| pos += snprintf(func_sig + pos, size - pos, \ |
| __VA_ARGS__); \ |
| if (pos >= size) \ |
| return -1; \ |
| } while (0) |
| #define BTF_PRINT_TYPE(type) \ |
| do { \ |
| pos = __btf_dumper_type_only(btf, type, func_sig, \ |
| pos, size); \ |
| if (pos == -1) \ |
| return -1; \ |
| } while (0) |
| |
| static int btf_dump_func(const struct btf *btf, char *func_sig, |
| const struct btf_type *func_proto, |
| const struct btf_type *func, int pos, int size); |
| |
| static int __btf_dumper_type_only(const struct btf *btf, __u32 type_id, |
| char *func_sig, int pos, int size) |
| { |
| const struct btf_type *proto_type; |
| const struct btf_array *array; |
| const struct btf_var *var; |
| const struct btf_type *t; |
| |
| if (!type_id) { |
| BTF_PRINT_ARG("void "); |
| return pos; |
| } |
| |
| t = btf__type_by_id(btf, type_id); |
| |
| switch (BTF_INFO_KIND(t->info)) { |
| case BTF_KIND_INT: |
| case BTF_KIND_TYPEDEF: |
| BTF_PRINT_ARG("%s ", btf__name_by_offset(btf, t->name_off)); |
| break; |
| case BTF_KIND_STRUCT: |
| BTF_PRINT_ARG("struct %s ", |
| btf__name_by_offset(btf, t->name_off)); |
| break; |
| case BTF_KIND_UNION: |
| BTF_PRINT_ARG("union %s ", |
| btf__name_by_offset(btf, t->name_off)); |
| break; |
| case BTF_KIND_ENUM: |
| BTF_PRINT_ARG("enum %s ", |
| btf__name_by_offset(btf, t->name_off)); |
| break; |
| case BTF_KIND_ARRAY: |
| array = (struct btf_array *)(t + 1); |
| BTF_PRINT_TYPE(array->type); |
| BTF_PRINT_ARG("[%d]", array->nelems); |
| break; |
| case BTF_KIND_PTR: |
| BTF_PRINT_TYPE(t->type); |
| BTF_PRINT_ARG("* "); |
| break; |
| case BTF_KIND_FWD: |
| BTF_PRINT_ARG("%s %s ", |
| BTF_INFO_KFLAG(t->info) ? "union" : "struct", |
| btf__name_by_offset(btf, t->name_off)); |
| break; |
| case BTF_KIND_VOLATILE: |
| BTF_PRINT_ARG("volatile "); |
| BTF_PRINT_TYPE(t->type); |
| break; |
| case BTF_KIND_CONST: |
| BTF_PRINT_ARG("const "); |
| BTF_PRINT_TYPE(t->type); |
| break; |
| case BTF_KIND_RESTRICT: |
| BTF_PRINT_ARG("restrict "); |
| BTF_PRINT_TYPE(t->type); |
| break; |
| case BTF_KIND_FUNC_PROTO: |
| pos = btf_dump_func(btf, func_sig, t, NULL, pos, size); |
| if (pos == -1) |
| return -1; |
| break; |
| case BTF_KIND_FUNC: |
| proto_type = btf__type_by_id(btf, t->type); |
| pos = btf_dump_func(btf, func_sig, proto_type, t, pos, size); |
| if (pos == -1) |
| return -1; |
| break; |
| case BTF_KIND_VAR: |
| var = (struct btf_var *)(t + 1); |
| if (var->linkage == BTF_VAR_STATIC) |
| BTF_PRINT_ARG("static "); |
| BTF_PRINT_TYPE(t->type); |
| BTF_PRINT_ARG(" %s", |
| btf__name_by_offset(btf, t->name_off)); |
| break; |
| case BTF_KIND_DATASEC: |
| BTF_PRINT_ARG("section (\"%s\") ", |
| btf__name_by_offset(btf, t->name_off)); |
| break; |
| case BTF_KIND_UNKN: |
| default: |
| return -1; |
| } |
| |
| return pos; |
| } |
| |
| static int btf_dump_func(const struct btf *btf, char *func_sig, |
| const struct btf_type *func_proto, |
| const struct btf_type *func, int pos, int size) |
| { |
| int i, vlen; |
| |
| BTF_PRINT_TYPE(func_proto->type); |
| if (func) |
| BTF_PRINT_ARG("%s(", btf__name_by_offset(btf, func->name_off)); |
| else |
| BTF_PRINT_ARG("("); |
| vlen = BTF_INFO_VLEN(func_proto->info); |
| for (i = 0; i < vlen; i++) { |
| struct btf_param *arg = &((struct btf_param *)(func_proto + 1))[i]; |
| |
| if (i) |
| BTF_PRINT_ARG(", "); |
| if (arg->type) { |
| BTF_PRINT_TYPE(arg->type); |
| BTF_PRINT_ARG("%s", |
| btf__name_by_offset(btf, arg->name_off)); |
| } else { |
| BTF_PRINT_ARG("..."); |
| } |
| } |
| BTF_PRINT_ARG(")"); |
| |
| return pos; |
| } |
| |
| void btf_dumper_type_only(const struct btf *btf, __u32 type_id, char *func_sig, |
| int size) |
| { |
| int err; |
| |
| func_sig[0] = '\0'; |
| if (!btf) |
| return; |
| |
| err = __btf_dumper_type_only(btf, type_id, func_sig, 0, size); |
| if (err < 0) |
| func_sig[0] = '\0'; |
| } |
| |
| static const char *ltrim(const char *s) |
| { |
| while (isspace(*s)) |
| s++; |
| |
| return s; |
| } |
| |
| void btf_dump_linfo_plain(const struct btf *btf, |
| const struct bpf_line_info *linfo, |
| const char *prefix, bool linum) |
| { |
| const char *line = btf__name_by_offset(btf, linfo->line_off); |
| |
| if (!line) |
| return; |
| line = ltrim(line); |
| |
| if (!prefix) |
| prefix = ""; |
| |
| if (linum) { |
| const char *file = btf__name_by_offset(btf, linfo->file_name_off); |
| |
| /* More forgiving on file because linum option is |
| * expected to provide more info than the already |
| * available src line. |
| */ |
| if (!file) |
| file = ""; |
| |
| printf("%s%s [file:%s line_num:%u line_col:%u]\n", |
| prefix, line, file, |
| BPF_LINE_INFO_LINE_NUM(linfo->line_col), |
| BPF_LINE_INFO_LINE_COL(linfo->line_col)); |
| } else { |
| printf("%s%s\n", prefix, line); |
| } |
| } |
| |
| void btf_dump_linfo_json(const struct btf *btf, |
| const struct bpf_line_info *linfo, bool linum) |
| { |
| const char *line = btf__name_by_offset(btf, linfo->line_off); |
| |
| if (line) |
| jsonw_string_field(json_wtr, "src", ltrim(line)); |
| |
| if (linum) { |
| const char *file = btf__name_by_offset(btf, linfo->file_name_off); |
| |
| if (file) |
| jsonw_string_field(json_wtr, "file", file); |
| |
| if (BPF_LINE_INFO_LINE_NUM(linfo->line_col)) |
| jsonw_int_field(json_wtr, "line_num", |
| BPF_LINE_INFO_LINE_NUM(linfo->line_col)); |
| |
| if (BPF_LINE_INFO_LINE_COL(linfo->line_col)) |
| jsonw_int_field(json_wtr, "line_col", |
| BPF_LINE_INFO_LINE_COL(linfo->line_col)); |
| } |
| } |