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源代码如下：
typedef struct _IMAGE_BASE_RELOCATION { DWORD VirtualAddress; DWORD SizeOfBlock; // WORD TypeOffset[1]; } IMAGE_BASE_RELOCATION; typedef IMAGE_BASE_RELOCATION UNALIGNED * PIMAGE_BASE_RELOCATION;
重定位表是一个数组，这个数组的大小记载在 _IMAGE_OPTIONAL_HEADER 的
.DataDirect??ory[IMAGE_DIRECTORY_E??NTRY_BASERELOC].Size 成员中
结构图如下，图片中 0 和 000 都表示16进制数，转换到二进制是 0000 和 0000 0000 0000：
每个元素的大小都记载在 SizeOfBlock 中，这个元素是由 一个 _IMAGE_BASE_RELOCATION 结构体和一个TypeOffset 数组组成的。TypeOffset 数组的每个元素占2个字节，其中，高4位是偏移类型（type），低12位表示需要重定位的地址（Offset），即，它与 VirtualAddress 相加即是指向 PE 映像中需要修改的那个代码的RVA。
偏移类型的含义如下：
|
Constant |
Value |
Description |
|
IMAGE_REL_BASED_ABSOLUTE |
0 |
The base relocation is skipped. This type can be used to pad a block. |
|
IMAGE_REL_BASED_HIGH |
1 |
The base relocation adds the high 16 bits of the difference to the 16bit field at offset. The 16-bit field represents the high value of a 32-bit word. |
|
IMAGE_REL_BASED_LOW |
2 |
The base relocation adds the low 16 bits of the difference to the 16-bit field at offset. The 16-bit field represents the low half of a 32-bit word. |
|
IMAGE_REL_BASED_HIGHLOW |
3 |
The base relocation applies all 32 bits of the difference to the 32-bit field at offset. |
|
IMAGE_REL_BASED_HIGHADJ |
4 |
The base relocation adds the high 16 bits of the difference to the 16-bit field at offset. The 16-bit field represents the high value of a 32-bit word. The low 16 bits of the 32-bit value are stored in the 16-bit word that follows this base relocation. This means that this base relocation occupies two slots. |
|
IMAGE_REL_BASED_MIPS_JMPADDR |
5 |
The relocation interpretation is dependent on the machine type. When the machine type is MIPS, the base relocation applies to a MIPS jump instruction. |
|
IMAGE_REL_BASED_ARM_MOV32 |
5 |
This relocation is meaningfull only when the machine type is ARM or Thumb. The base relocation applies the 32-bit address of a symbol across a consecutive MOVW/MOVT instruction pair. |
|
IMAGE_REL_BASED_RISCV_HIGH20 |
5 |
This relocation is only meaningful when the machine type is RISC-V. The base relocation applies to the high 20 bits of a 32-bit absolute address. |
|
|
6 |
Reserved, must be zero. |
|
IMAGE_REL_BASED_THUMB_MOV32 |
7 |
This relocation is meaningful only when the machine type is Thumb. The base relocation applies the 32-bit address of a symbol to a consecutive MOVW/MOVT instruction pair. |
|
IMAGE_REL_BASED_RISCV_LOW12I |
7 |
This relocation is only meaningful when the machine type is RISC-V. The base relocation applies to the low 12 bits of a 32-bit absolute address formed in RISC-V I-type instruction format. |
|
IMAGE_REL_BASED_RISCV_LOW12S |
8 |
This relocation is only meaningful when the machine type is RISC-V. The base relocation applies to the low 12 bits of a 32-bit absolute address formed in RISC-V S-type instruction format. |
|
IMAGE_REL_BASED_MIPS_JMPADDR16 |
9 |
The relocation is only meaningful when the machine type is MIPS. The base relocation applies to a MIPS16 jump instruction. |
|
IMAGE_REL_BASED_DIR64 |
10 |
The base relocation applies the difference to the 64-bit field at offset. |
其他中文翻译：
| 常量 | 值 | 描述 |
| IMAGE_REL_BASED_ABSOLUTE | 0x0 | 使块按照32位对齐，位置为0。 |
| IMAGE_REL_BASED_HIGH | 0x1 | 高16位必须应用于偏移量所指高字16位。 |
| IMAGE_REL_BASED_LOW | 0x2 | 低16位必须应用于偏移量所指低字16位。 |
| IMAGE_REL_BASED_HIGHLOW | 0x3 | 全部32位应用于所有32位。 |
| IMAGE_REL_BASED_HIGHADJ | 0x4 | 需要32位，高16位位于偏移量，低16位位于下一个偏移量数组元素，组合为一个带符号数，加上32位的一个数，然后加上8000然后把高16位保存在偏移量的16位域内。 |
例子：
分析常见的dll：在QQ中的 zlib.dll 文件 （在QQ安装目录下的bin文件夹中）：
首先找到重定位表，这里使用工具：
找到数据：
VirtualAddress 为 0x1000，SizeOfBlock 为 0x64。第一个条目为 0x338C，高四位为 0x3，offset为 0x38C，即偏移地址为 0x138C （由 0x1000 + 0x38C得来）应用于此地址上全部32位。打开C32Asm反汇编查看：
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原文地址：http://www.cnblogs.com/night-ride-depart/p/5779043.html
