diff options
Diffstat (limited to 'tools/bpf/bpftool/btf_dumper.c')
-rw-r--r-- | tools/bpf/bpftool/btf_dumper.c | 245 |
1 files changed, 226 insertions, 19 deletions
diff --git a/tools/bpf/bpftool/btf_dumper.c b/tools/bpf/bpftool/btf_dumper.c index 01cc52b834fa..19924b6ce796 100644 --- a/tools/bpf/bpftool/btf_dumper.c +++ b/tools/bpf/bpftool/btf_dumper.c @@ -4,11 +4,13 @@ #include <ctype.h> #include <stdio.h> /* for (FILE *) used by json_writer */ #include <string.h> +#include <unistd.h> #include <asm/byteorder.h> #include <linux/bitops.h> #include <linux/btf.h> #include <linux/err.h> #include <bpf/btf.h> +#include <bpf/bpf.h> #include "json_writer.h" #include "main.h" @@ -22,13 +24,112 @@ 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) +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 dump_prog_id_as_func_ptr(const struct btf_dumper *d, + const struct btf_type *func_proto, + __u32 prog_id) { - if (is_plain_text) - jsonw_printf(jw, "%p", *(void **)data); + const struct btf_type *func_type; + int prog_fd = -1, func_sig_len; + struct bpf_prog_info info = {}; + __u32 info_len = sizeof(info); + const char *prog_name = NULL; + struct btf *prog_btf = NULL; + struct bpf_func_info finfo; + __u32 finfo_rec_size; + char prog_str[1024]; + int err; + + /* Get the ptr's func_proto */ + func_sig_len = btf_dump_func(d->btf, prog_str, func_proto, NULL, 0, + sizeof(prog_str)); + if (func_sig_len == -1) + return -1; + + if (!prog_id) + goto print; + + /* Get the bpf_prog's name. Obtain from func_info. */ + prog_fd = bpf_prog_get_fd_by_id(prog_id); + if (prog_fd < 0) + goto print; + + err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len); + if (err) + goto print; + + if (!info.btf_id || !info.nr_func_info) + goto print; + + finfo_rec_size = info.func_info_rec_size; + memset(&info, 0, sizeof(info)); + info.nr_func_info = 1; + info.func_info_rec_size = finfo_rec_size; + info.func_info = ptr_to_u64(&finfo); + + err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len); + if (err) + goto print; + + prog_btf = btf__load_from_kernel_by_id(info.btf_id); + if (libbpf_get_error(prog_btf)) + goto print; + func_type = btf__type_by_id(prog_btf, finfo.type_id); + if (!func_type || !btf_is_func(func_type)) + goto print; + + prog_name = btf__name_by_offset(prog_btf, func_type->name_off); + +print: + if (!prog_id) + snprintf(&prog_str[func_sig_len], + sizeof(prog_str) - func_sig_len, " 0"); + else if (prog_name) + snprintf(&prog_str[func_sig_len], + sizeof(prog_str) - func_sig_len, + " %s/prog_id:%u", prog_name, prog_id); else - jsonw_printf(jw, "%lu", *(unsigned long *)data); + snprintf(&prog_str[func_sig_len], + sizeof(prog_str) - func_sig_len, + " <unknown_prog_name>/prog_id:%u", prog_id); + + prog_str[sizeof(prog_str) - 1] = '\0'; + jsonw_string(d->jw, prog_str); + btf__free(prog_btf); + if (prog_fd >= 0) + close(prog_fd); + return 0; +} + +static void btf_dumper_ptr(const struct btf_dumper *d, + const struct btf_type *t, + const void *data) +{ + unsigned long value = *(unsigned long *)data; + const struct btf_type *ptr_type; + __s32 ptr_type_id; + + if (!d->prog_id_as_func_ptr || value > UINT32_MAX) + goto print_ptr_value; + + ptr_type_id = btf__resolve_type(d->btf, t->type); + if (ptr_type_id < 0) + goto print_ptr_value; + ptr_type = btf__type_by_id(d->btf, ptr_type_id); + if (!ptr_type || !btf_is_func_proto(ptr_type)) + goto print_ptr_value; + + if (!dump_prog_id_as_func_ptr(d, ptr_type, value)) + return; + +print_ptr_value: + if (d->is_plain_text) + jsonw_printf(d->jw, "%p", (void *)value); + else + jsonw_printf(d->jw, "%lu", value); } static int btf_dumper_modifier(const struct btf_dumper *d, __u32 type_id, @@ -43,9 +144,104 @@ static int btf_dumper_modifier(const struct btf_dumper *d, __u32 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) +static int btf_dumper_enum(const struct btf_dumper *d, + const struct btf_type *t, + const void *data) { - jsonw_printf(jw, "%d", *(int *)data); + const struct btf_enum *enums = btf_enum(t); + __s64 value; + __u16 i; + + switch (t->size) { + case 8: + value = *(__s64 *)data; + break; + case 4: + value = *(__s32 *)data; + break; + case 2: + value = *(__s16 *)data; + break; + case 1: + value = *(__s8 *)data; + break; + default: + return -EINVAL; + } + + for (i = 0; i < btf_vlen(t); i++) { + if (value == enums[i].val) { + jsonw_string(d->jw, + btf__name_by_offset(d->btf, + enums[i].name_off)); + return 0; + } + } + + jsonw_int(d->jw, value); + return 0; +} + +static int btf_dumper_enum64(const struct btf_dumper *d, + const struct btf_type *t, + const void *data) +{ + const struct btf_enum64 *enums = btf_enum64(t); + __u32 val_lo32, val_hi32; + __u64 value; + __u16 i; + + value = *(__u64 *)data; + val_lo32 = (__u32)value; + val_hi32 = value >> 32; + + for (i = 0; i < btf_vlen(t); i++) { + if (val_lo32 == enums[i].val_lo32 && val_hi32 == enums[i].val_hi32) { + jsonw_string(d->jw, + btf__name_by_offset(d->btf, + enums[i].name_off)); + return 0; + } + } + + jsonw_int(d->jw, value); + return 0; +} + +static bool is_str_array(const struct btf *btf, const struct btf_array *arr, + const char *s) +{ + const struct btf_type *elem_type; + const char *end_s; + + if (!arr->nelems) + return false; + + elem_type = btf__type_by_id(btf, arr->type); + /* Not skipping typedef. typedef to char does not count as + * a string now. + */ + while (elem_type && btf_is_mod(elem_type)) + elem_type = btf__type_by_id(btf, elem_type->type); + + if (!elem_type || !btf_is_int(elem_type) || elem_type->size != 1) + return false; + + if (btf_int_encoding(elem_type) != BTF_INT_CHAR && + strcmp("char", btf__name_by_offset(btf, elem_type->name_off))) + return false; + + end_s = s + arr->nelems; + while (s < end_s) { + if (!*s) + return true; + if (*s <= 0x1f || *s >= 0x7f) + return false; + s++; + } + + /* '\0' is not found */ + return false; } static int btf_dumper_array(const struct btf_dumper *d, __u32 type_id, @@ -57,6 +253,11 @@ static int btf_dumper_array(const struct btf_dumper *d, __u32 type_id, int ret = 0; __u32 i; + if (is_str_array(d->btf, arr, data)) { + jsonw_string(d->jw, data); + return 0; + } + elem_size = btf__resolve_size(d->btf, arr->type); if (elem_size < 0) return elem_size; @@ -106,8 +307,8 @@ static void btf_int128_print(json_writer_t *jw, const void *data, } } -static void btf_int128_shift(__u64 *print_num, u16 left_shift_bits, - u16 right_shift_bits) +static void btf_int128_shift(__u64 *print_num, __u16 left_shift_bits, + __u16 right_shift_bits) { __u64 upper_num, lower_num; @@ -251,7 +452,7 @@ static int btf_dumper_int(const struct btf_type *t, __u8 bit_offset, *(char *)data); break; case BTF_INT_BOOL: - jsonw_bool(jw, *(int *)data); + jsonw_bool(jw, *(bool *)data); break; default: /* shouldn't happen */ @@ -366,10 +567,11 @@ static int btf_dumper_do_type(const struct btf_dumper *d, __u32 type_id, case BTF_KIND_ARRAY: return btf_dumper_array(d, type_id, data); case BTF_KIND_ENUM: - btf_dumper_enum(data, d->jw); - return 0; + return btf_dumper_enum(d, t, data); + case BTF_KIND_ENUM64: + return btf_dumper_enum64(d, t, data); case BTF_KIND_PTR: - btf_dumper_ptr(data, d->jw, d->is_plain_text); + btf_dumper_ptr(d, t, data); return 0; case BTF_KIND_UNKN: jsonw_printf(d->jw, "(unknown)"); @@ -414,10 +616,6 @@ int btf_dumper_type(const struct btf_dumper *d, __u32 type_id, 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) { @@ -436,6 +634,7 @@ static int __btf_dumper_type_only(const struct btf *btf, __u32 type_id, switch (BTF_INFO_KIND(t->info)) { case BTF_KIND_INT: case BTF_KIND_TYPEDEF: + case BTF_KIND_FLOAT: BTF_PRINT_ARG("%s ", btf__name_by_offset(btf, t->name_off)); break; case BTF_KIND_STRUCT: @@ -447,6 +646,7 @@ static int __btf_dumper_type_only(const struct btf *btf, __u32 type_id, btf__name_by_offset(btf, t->name_off)); break; case BTF_KIND_ENUM: + case BTF_KIND_ENUM64: BTF_PRINT_ARG("enum %s ", btf__name_by_offset(btf, t->name_off)); break; @@ -526,8 +726,15 @@ static int btf_dump_func(const struct btf *btf, char *func_sig, BTF_PRINT_ARG(", "); if (arg->type) { BTF_PRINT_TYPE(arg->type); - BTF_PRINT_ARG("%s", - btf__name_by_offset(btf, arg->name_off)); + if (arg->name_off) + BTF_PRINT_ARG("%s", + btf__name_by_offset(btf, arg->name_off)); + else if (pos && func_sig[pos - 1] == ' ') + /* Remove unnecessary space for + * FUNC_PROTO that does not have + * arg->name_off + */ + func_sig[--pos] = '\0'; } else { BTF_PRINT_ARG("..."); } |