ptrace-arm.c revision 501edd29b823ce1301d2effdd3a9e4b6e2b20b76 
1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "Corkscrew"
18//#define LOG_NDEBUG 0
19
20#include "../ptrace-arch.h"
21
22#include <sys/exec_elf.h>
23#include <cutils/log.h>
24
25#ifndef PT_ARM_EXIDX
26#define PT_ARM_EXIDX 0x70000001
27#endif
28
29static void load_exidx_header(pid_t pid, map_info_t* mi,
30        uintptr_t* out_exidx_start, size_t* out_exidx_size) {
31    uint32_t elf_phoff;
32    uint32_t elf_phnum;
33    if (try_get_word(pid, mi->start + offsetof(Elf32_Ehdr, e_phoff), &elf_phoff)
34            && try_get_word(pid, mi->start + offsetof(Elf32_Ehdr, e_phnum), &elf_phnum)) {
35        for (uint32_t i = 0; i < elf_phnum; i++) {
36            uintptr_t elf_phdr = mi->start + elf_phoff + i * sizeof(Elf32_Phdr);
37            uint32_t elf_phdr_type;
38            if (!try_get_word(pid, elf_phdr + offsetof(Elf32_Phdr, p_type), &elf_phdr_type)) {
39                break;
40            }
41            if (elf_phdr_type == PT_ARM_EXIDX) {
42                uint32_t elf_phdr_offset;
43                uint32_t elf_phdr_filesz;
44                if (!try_get_word(pid, elf_phdr + offsetof(Elf32_Phdr, p_offset),
45                        &elf_phdr_offset)
46                        || !try_get_word(pid, elf_phdr + offsetof(Elf32_Phdr, p_filesz),
47                                &elf_phdr_filesz)) {
48                    break;
49                }
50                *out_exidx_start = mi->start + elf_phdr_offset;
51                *out_exidx_size = elf_phdr_filesz;
52                return;
53            }
54        }
55    }
56    *out_exidx_start = 0;
57    *out_exidx_size = 0;
58}
59
60void load_ptrace_map_info_data_arch(pid_t pid, map_info_t* mi, map_info_data_t* data) {
61    load_exidx_header(pid, mi, &data->exidx_start, &data->exidx_size);
62}
63
64void free_ptrace_map_info_data_arch(map_info_t* mi, map_info_data_t* data) {
65}
66