| // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) |
| /* Copyright (C) 2018 Netronome Systems, Inc. */ |
| |
| #define _GNU_SOURCE |
| #include <stdarg.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/types.h> |
| #include <bpf/libbpf.h> |
| #include <bpf/libbpf_internal.h> |
| |
| #include "disasm.h" |
| #include "json_writer.h" |
| #include "main.h" |
| #include "xlated_dumper.h" |
| |
| static int kernel_syms_cmp(const void *sym_a, const void *sym_b) |
| { |
| return ((struct kernel_sym *)sym_a)->address - |
| ((struct kernel_sym *)sym_b)->address; |
| } |
| |
| void kernel_syms_load(struct dump_data *dd) |
| { |
| struct kernel_sym *sym; |
| char buff[256]; |
| void *tmp, *address; |
| FILE *fp; |
| |
| fp = fopen("/proc/kallsyms", "r"); |
| if (!fp) |
| return; |
| |
| while (fgets(buff, sizeof(buff), fp)) { |
| tmp = libbpf_reallocarray(dd->sym_mapping, dd->sym_count + 1, |
| sizeof(*dd->sym_mapping)); |
| if (!tmp) { |
| out: |
| free(dd->sym_mapping); |
| dd->sym_mapping = NULL; |
| fclose(fp); |
| return; |
| } |
| dd->sym_mapping = tmp; |
| sym = &dd->sym_mapping[dd->sym_count]; |
| if (sscanf(buff, "%p %*c %s", &address, sym->name) != 2) |
| continue; |
| sym->address = (unsigned long)address; |
| if (!strcmp(sym->name, "__bpf_call_base")) { |
| dd->address_call_base = sym->address; |
| /* sysctl kernel.kptr_restrict was set */ |
| if (!sym->address) |
| goto out; |
| } |
| if (sym->address) |
| dd->sym_count++; |
| } |
| |
| fclose(fp); |
| |
| qsort(dd->sym_mapping, dd->sym_count, |
| sizeof(*dd->sym_mapping), kernel_syms_cmp); |
| } |
| |
| void kernel_syms_destroy(struct dump_data *dd) |
| { |
| free(dd->sym_mapping); |
| } |
| |
| struct kernel_sym *kernel_syms_search(struct dump_data *dd, |
| unsigned long key) |
| { |
| struct kernel_sym sym = { |
| .address = key, |
| }; |
| |
| return dd->sym_mapping ? |
| bsearch(&sym, dd->sym_mapping, dd->sym_count, |
| sizeof(*dd->sym_mapping), kernel_syms_cmp) : NULL; |
| } |
| |
| static void __printf(2, 3) print_insn(void *private_data, const char *fmt, ...) |
| { |
| va_list args; |
| |
| va_start(args, fmt); |
| vprintf(fmt, args); |
| va_end(args); |
| } |
| |
| static void __printf(2, 3) |
| print_insn_for_graph(void *private_data, const char *fmt, ...) |
| { |
| char buf[64], *p; |
| va_list args; |
| |
| va_start(args, fmt); |
| vsnprintf(buf, sizeof(buf), fmt, args); |
| va_end(args); |
| |
| p = buf; |
| while (*p != '\0') { |
| if (*p == '\n') { |
| memmove(p + 3, p, strlen(buf) + 1 - (p - buf)); |
| /* Align each instruction dump row left. */ |
| *p++ = '\\'; |
| *p++ = 'l'; |
| /* Output multiline concatenation. */ |
| *p++ = '\\'; |
| } else if (*p == '<' || *p == '>' || *p == '|' || *p == '&') { |
| memmove(p + 1, p, strlen(buf) + 1 - (p - buf)); |
| /* Escape special character. */ |
| *p++ = '\\'; |
| } |
| |
| p++; |
| } |
| |
| printf("%s", buf); |
| } |
| |
| static void __printf(2, 3) |
| print_insn_json(void *private_data, const char *fmt, ...) |
| { |
| unsigned int l = strlen(fmt); |
| char chomped_fmt[l]; |
| va_list args; |
| |
| va_start(args, fmt); |
| if (l > 0) { |
| strncpy(chomped_fmt, fmt, l - 1); |
| chomped_fmt[l - 1] = '\0'; |
| } |
| jsonw_vprintf_enquote(json_wtr, chomped_fmt, args); |
| va_end(args); |
| } |
| |
| static const char *print_call_pcrel(struct dump_data *dd, |
| struct kernel_sym *sym, |
| unsigned long address, |
| const struct bpf_insn *insn) |
| { |
| if (!dd->nr_jited_ksyms) |
| /* Do not show address for interpreted programs */ |
| snprintf(dd->scratch_buff, sizeof(dd->scratch_buff), |
| "%+d", insn->off); |
| else if (sym) |
| snprintf(dd->scratch_buff, sizeof(dd->scratch_buff), |
| "%+d#%s", insn->off, sym->name); |
| else |
| snprintf(dd->scratch_buff, sizeof(dd->scratch_buff), |
| "%+d#0x%lx", insn->off, address); |
| return dd->scratch_buff; |
| } |
| |
| static const char *print_call_helper(struct dump_data *dd, |
| struct kernel_sym *sym, |
| unsigned long address) |
| { |
| if (sym) |
| snprintf(dd->scratch_buff, sizeof(dd->scratch_buff), |
| "%s", sym->name); |
| else |
| snprintf(dd->scratch_buff, sizeof(dd->scratch_buff), |
| "0x%lx", address); |
| return dd->scratch_buff; |
| } |
| |
| static const char *print_call(void *private_data, |
| const struct bpf_insn *insn) |
| { |
| struct dump_data *dd = private_data; |
| unsigned long address = dd->address_call_base + insn->imm; |
| struct kernel_sym *sym; |
| |
| if (insn->src_reg == BPF_PSEUDO_CALL && |
| (__u32) insn->imm < dd->nr_jited_ksyms && dd->jited_ksyms) |
| address = dd->jited_ksyms[insn->imm]; |
| |
| sym = kernel_syms_search(dd, address); |
| if (insn->src_reg == BPF_PSEUDO_CALL) |
| return print_call_pcrel(dd, sym, address, insn); |
| else |
| return print_call_helper(dd, sym, address); |
| } |
| |
| static const char *print_imm(void *private_data, |
| const struct bpf_insn *insn, |
| __u64 full_imm) |
| { |
| struct dump_data *dd = private_data; |
| |
| if (insn->src_reg == BPF_PSEUDO_MAP_FD) |
| snprintf(dd->scratch_buff, sizeof(dd->scratch_buff), |
| "map[id:%u]", insn->imm); |
| else if (insn->src_reg == BPF_PSEUDO_MAP_VALUE) |
| snprintf(dd->scratch_buff, sizeof(dd->scratch_buff), |
| "map[id:%u][0]+%u", insn->imm, (insn + 1)->imm); |
| else if (insn->src_reg == BPF_PSEUDO_MAP_IDX_VALUE) |
| snprintf(dd->scratch_buff, sizeof(dd->scratch_buff), |
| "map[idx:%u]+%u", insn->imm, (insn + 1)->imm); |
| else if (insn->src_reg == BPF_PSEUDO_FUNC) |
| snprintf(dd->scratch_buff, sizeof(dd->scratch_buff), |
| "subprog[%+d]", insn->imm); |
| else |
| snprintf(dd->scratch_buff, sizeof(dd->scratch_buff), |
| "0x%llx", (unsigned long long)full_imm); |
| return dd->scratch_buff; |
| } |
| |
| void dump_xlated_json(struct dump_data *dd, void *buf, unsigned int len, |
| bool opcodes, bool linum) |
| { |
| const struct bpf_prog_linfo *prog_linfo = dd->prog_linfo; |
| const struct bpf_insn_cbs cbs = { |
| .cb_print = print_insn_json, |
| .cb_call = print_call, |
| .cb_imm = print_imm, |
| .private_data = dd, |
| }; |
| struct bpf_func_info *record; |
| struct bpf_insn *insn = buf; |
| struct btf *btf = dd->btf; |
| bool double_insn = false; |
| unsigned int nr_skip = 0; |
| char func_sig[1024]; |
| unsigned int i; |
| |
| jsonw_start_array(json_wtr); |
| record = dd->func_info; |
| for (i = 0; i < len / sizeof(*insn); i++) { |
| if (double_insn) { |
| double_insn = false; |
| continue; |
| } |
| double_insn = insn[i].code == (BPF_LD | BPF_IMM | BPF_DW); |
| |
| jsonw_start_object(json_wtr); |
| |
| if (btf && record) { |
| if (record->insn_off == i) { |
| btf_dumper_type_only(btf, record->type_id, |
| func_sig, |
| sizeof(func_sig)); |
| if (func_sig[0] != '\0') { |
| jsonw_name(json_wtr, "proto"); |
| jsonw_string(json_wtr, func_sig); |
| } |
| record = (void *)record + dd->finfo_rec_size; |
| } |
| } |
| |
| if (prog_linfo) { |
| const struct bpf_line_info *linfo; |
| |
| linfo = bpf_prog_linfo__lfind(prog_linfo, i, nr_skip); |
| if (linfo) { |
| btf_dump_linfo_json(btf, linfo, linum); |
| nr_skip++; |
| } |
| } |
| |
| jsonw_name(json_wtr, "disasm"); |
| print_bpf_insn(&cbs, insn + i, true); |
| |
| if (opcodes) { |
| jsonw_name(json_wtr, "opcodes"); |
| jsonw_start_object(json_wtr); |
| |
| jsonw_name(json_wtr, "code"); |
| jsonw_printf(json_wtr, "\"0x%02hhx\"", insn[i].code); |
| |
| jsonw_name(json_wtr, "src_reg"); |
| jsonw_printf(json_wtr, "\"0x%hhx\"", insn[i].src_reg); |
| |
| jsonw_name(json_wtr, "dst_reg"); |
| jsonw_printf(json_wtr, "\"0x%hhx\"", insn[i].dst_reg); |
| |
| jsonw_name(json_wtr, "off"); |
| print_hex_data_json((uint8_t *)(&insn[i].off), 2); |
| |
| jsonw_name(json_wtr, "imm"); |
| if (double_insn && i < len - 1) |
| print_hex_data_json((uint8_t *)(&insn[i].imm), |
| 12); |
| else |
| print_hex_data_json((uint8_t *)(&insn[i].imm), |
| 4); |
| jsonw_end_object(json_wtr); |
| } |
| jsonw_end_object(json_wtr); |
| } |
| jsonw_end_array(json_wtr); |
| } |
| |
| void dump_xlated_plain(struct dump_data *dd, void *buf, unsigned int len, |
| bool opcodes, bool linum) |
| { |
| const struct bpf_prog_linfo *prog_linfo = dd->prog_linfo; |
| const struct bpf_insn_cbs cbs = { |
| .cb_print = print_insn, |
| .cb_call = print_call, |
| .cb_imm = print_imm, |
| .private_data = dd, |
| }; |
| struct bpf_func_info *record; |
| struct bpf_insn *insn = buf; |
| struct btf *btf = dd->btf; |
| unsigned int nr_skip = 0; |
| bool double_insn = false; |
| char func_sig[1024]; |
| unsigned int i; |
| |
| record = dd->func_info; |
| for (i = 0; i < len / sizeof(*insn); i++) { |
| if (double_insn) { |
| double_insn = false; |
| continue; |
| } |
| |
| if (btf && record) { |
| if (record->insn_off == i) { |
| btf_dumper_type_only(btf, record->type_id, |
| func_sig, |
| sizeof(func_sig)); |
| if (func_sig[0] != '\0') |
| printf("%s:\n", func_sig); |
| record = (void *)record + dd->finfo_rec_size; |
| } |
| } |
| |
| if (prog_linfo) { |
| const struct bpf_line_info *linfo; |
| |
| linfo = bpf_prog_linfo__lfind(prog_linfo, i, nr_skip); |
| if (linfo) { |
| btf_dump_linfo_plain(btf, linfo, "; ", |
| linum); |
| nr_skip++; |
| } |
| } |
| |
| double_insn = insn[i].code == (BPF_LD | BPF_IMM | BPF_DW); |
| |
| printf("% 4d: ", i); |
| print_bpf_insn(&cbs, insn + i, true); |
| |
| if (opcodes) { |
| printf(" "); |
| fprint_hex(stdout, insn + i, 8, " "); |
| if (double_insn && i < len - 1) { |
| printf(" "); |
| fprint_hex(stdout, insn + i + 1, 8, " "); |
| } |
| printf("\n"); |
| } |
| } |
| } |
| |
| void dump_xlated_for_graph(struct dump_data *dd, void *buf_start, void *buf_end, |
| unsigned int start_idx) |
| { |
| const struct bpf_insn_cbs cbs = { |
| .cb_print = print_insn_for_graph, |
| .cb_call = print_call, |
| .cb_imm = print_imm, |
| .private_data = dd, |
| }; |
| struct bpf_insn *insn_start = buf_start; |
| struct bpf_insn *insn_end = buf_end; |
| struct bpf_insn *cur = insn_start; |
| |
| for (; cur <= insn_end; cur++) { |
| printf("% 4d: ", (int)(cur - insn_start + start_idx)); |
| print_bpf_insn(&cbs, cur, true); |
| if (cur != insn_end) |
| printf(" | "); |
| } |
| } |