慎用strip(2)

2007-10-12 10:51

>readelf -a test >1
>readelf -a test.orig >2
>cat 1
ELF 头：
Magic： 7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00
Class:                             ELF32
Data:                              2's complement, little endian
Version:                           1 (current)
OS/ABI:                            UNIX - System V
ABI Version:                       0
Type:                              EXEC (可执行文件)
Machine:                           Intel 80386
Version:                           0x1
入口点地址：              0x8048350
程序头起点：              52 (bytes into file)
Start of section headers:          2196 (bytes into file)
标志：             0x0
本头的大小：       52 (字节)
程序头大小：       32 (字节)
程序头数量：       8
节头大小：         40 (字节)
节头数量：         27
字符串表索引节头： 26

节头：
[Nr] Name              Type            Addr     Off    Size   ES Flg Lk Inf Al
[ 0]                   NULL            00000000 000000 000000 00      0   0 0
[ 1] .interp           PROGBITS        08048134 000134 000013 00   A 0   0 1
[ 2] .note.ABI-tag     NOTE            08048148 000148 000020 00   A 0   0 4
[ 3] .note.SuSE        NOTE            08048168 000168 000018 00   A 0   0 4
[ 4] .hash             HASH            08048180 000180 000030 04   A 5   0 4
[ 5] .dynsym           DYNSYM          080481b0 0001b0 000070 10   A 6   1 4
[ 6] .dynstr           STRTAB          08048220 000220 000066 00   A 0   0 1
[ 7] .gnu.version      VERSYM          08048286 000286 00000e 02   A 5   0 2
[ 8] .gnu.version_r    VERNEED         08048294 000294 000020 00   A 6   1 4
[ 9] .rel.dyn          REL             080482b4 0002b4 000008 08   A 5   0 4
[10] .rel.plt          REL             080482bc 0002bc 000020 08   A 5 12 4
[11] .init             PROGBITS        080482dc 0002dc 000017 00 AX 0   0 4
[12] .plt              PROGBITS        080482f4 0002f4 000050 04 AX 0   0 4
[13] .text             PROGBITS        08048350 000350 00021c 00 AX 0   0 16
[14] .fini             PROGBITS        0804856c 00056c 00001c 00 AX 0   0 4
[15] .rodata           PROGBITS        08048588 000588 000013 00   A 0   0 4
[16] .eh_frame         PROGBITS        0804859c 00059c 000004 00   A 0   0 4
[17] .ctors            PROGBITS        080495a0 0005a0 000008 00 WA 0   0 4
[18] .dtors            PROGBITS        080495a8 0005a8 000008 00 WA 0   0 4
[19] .jcr              PROGBITS        080495b0 0005b0 000004 00 WA 0   0 4
[20] .dynamic          DYNAMIC         080495b4 0005b4 0000c8 08 WA 6   0 4
[21] .got              PROGBITS        0804967c 00067c 000004 04 WA 0   0 4
[22] .got.plt          PROGBITS        08049680 000680 00001c 04 WA 0   0 4
[23] .data             PROGBITS        0804969c 00069c 00000c 00 WA 0   0 4
[24] .bss              NOBITS          080496a8 0006a8 000004 00 WA 0   0 4
[25] .comment          PROGBITS        00000000 0006a8 000117 00      0   0 1
[26] .shstrtab         STRTAB          00000000 0007bf 0000d2 00      0   0 1
Key to Flags:
W (write), A (alloc), X (execute), M (merge), S (strings)
I (info), L (link order), G (group), x (unknown)
O (extra OS processing required) o (OS specific), p (processor specific)

There are no section groups in this file.

程序头：
Type           Offset   VirtAddr   PhysAddr   FileSiz MemSiz Flg Align
PHDR           0x000034 0x08048034 0x08048034 0x00100 0x00100 R E 0x4
INTERP         0x000134 0x08048134 0x08048134 0x00013 0x00013 R   0x1
      [正在请求程序解释器：/lib/ld-linux.so.2]
LOAD           0x000000 0x08048000 0x08048000 0x005a0 0x005a0 R E 0x1000
LOAD           0x0005a0 0x080495a0 0x080495a0 0x00108 0x0010c RW 0x1000
DYNAMIC        0x0005b4 0x080495b4 0x080495b4 0x000c8 0x000c8 RW 0x4
NOTE           0x000148 0x08048148 0x08048148 0x00020 0x00020 R   0x4
NOTE           0x000168 0x08048168 0x08048168 0x00018 0x00018 R   0x4
GNU_STACK      0x000000 0x00000000 0x00000000 0x00000 0x00000 RW 0x4

Section to Segment mapping:
段节...
   00
   01     .interp
   02     .interp .note.ABI-tag .note.SuSE .hash .dynsym .dynstr .gnu.version .gnu.version_r .rel.dyn .rel.plt .init .plt .text .fini .rodata .eh_frame
   03     .ctors .dtors .jcr .dynamic .got .got.plt .data .bss
   04     .dynamic
   05     .note.ABI-tag
   06     .note.SuSE
   07

Dynamic section at offset 0x5b4 contains 20 entries:
标记        类型                         名称/值
0x00000001 (NEEDED)                     共享库：[libc.so.6]
0x0000000c (INIT)                       0x80482dc
0x0000000d (FINI)                       0x804856c
0x00000004 (HASH)                       0x8048180
0x00000005 (STRTAB)                     0x8048220
0x00000006 (SYMTAB)                     0x80481b0
0x0000000a (STRSZ)                      102 (bytes)
0x0000000b (SYMENT)                     16 (bytes)
0x00000015 (DEBUG)                      0x0
0x00000003 (PLTGOT)                     0x8049680
0x00000002 (PLTRELSZ)                   32 (bytes)
0x00000014 (PLTREL)                     REL
0x00000017 (JMPREL)                     0x80482bc
0x00000011 (REL)                        0x80482b4
0x00000012 (RELSZ)                      8 (bytes)
0x00000013 (RELENT)                     8 (bytes)
0x6ffffffe (VERNEED)                    0x8048294
0x6fffffff (VERNEEDNUM)                 1
0x6ffffff0 (VERSYM)                     0x8048286
0x00000000 (NULL)                       0x0

重定位节 “.rel.dyn” 位于偏移量 0x2b4 含有 1 个条目：
Offset     Info    Type            Sym.Value Sym. Name
0804967c 00000606 R_386_GLOB_DAT    00000000   __gmon_start__

重定位节 “.rel.plt” 位于偏移量 0x2bc 含有 4 个条目：
Offset     Info    Type            Sym.Value Sym. Name
0804968c 00000107 R_386_JUMP_SLOT   00000000   scanf
08049690 00000207 R_386_JUMP_SLOT   00000000   __libc_start_main
08049694 00000307 R_386_JUMP_SLOT   00000000   printf
08049698 00000607 R_386_JUMP_SLOT   00000000   __gmon_start__

There are no unwind sections in this file.

Symbol table '.dynsym' contains 7 entries:
   Num:    Value Size Type    Bind   Vis      Ndx Name
     0: 00000000     0 NOTYPE LOCAL DEFAULT UND
     1: 00000000    65 FUNC    GLOBAL DEFAULT UND scanf@GLIBC_2.0 (2)
     2: 00000000   415 FUNC    GLOBAL DEFAULT UND __libc_start_main@GLIBC_2.0 (2)
     3: 00000000    57 FUNC    GLOBAL DEFAULT UND printf@GLIBC_2.0 (2)
     4: 0804858c     4 OBJECT GLOBAL DEFAULT   15 _IO_stdin_used
     5: 00000000     0 NOTYPE WEAK   DEFAULT UND _Jv_RegisterClasses
     6: 00000000     0 NOTYPE WEAK   DEFAULT UND __gmon_start__

Histogram for bucket list length (total of 3 buckets):
Length Number     % of total Coverage
      0 0          ( 0.0%)
      1 0          ( 0.0%)      0.0%
      2 3          (100.0%)    100.0%

版本符号节“.gnu.version”含有 7 个条目：
地址：0000000008048286 偏移量：0x000286 连接：5 (.dynsym)
000:   0 (*本地*)       2 (GLIBC_2.0)     2 (GLIBC_2.0)     2 (GLIBC_2.0)
004:   1 (*全局*)      0 (*本地*)       0 (*本地*)

Version needs section '.gnu.version_r' contains 1 entries:
地址：0x0000000008048294 Offset: 0x000294 Link to section: 6 (.dynstr)
000000: Version: 1 文件：libc.so.6 计数：1
0x0010:   Name: GLIBC_2.0 标志：无 版本：2

注释位于偏移量 0x00000148 长度为 0x00000020：
所有者                数据大小        描述
GNU           0x00000010      NT_VERSION (version)

注释位于偏移量 0x00000168 长度为 0x00000018：
所有者                数据大小        描述
SuSE          0x00000004      未知的注释类型：(0x45537553)



>cat 2
ELF 头：
Magic： 7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00
Class:                             ELF32
Data:                              2's complement, little endian
Version:                           1 (current)
OS/ABI:                            UNIX - System V
ABI Version:                       0
Type:                              EXEC (可执行文件)
Machine:                           Intel 80386
Version:                           0x1
入口点地址：              0x8048350
程序头起点：              52 (bytes into file)
Start of section headers:          3392 (bytes into file)
标志：             0x0
本头的大小：       52 (字节)
程序头大小：       32 (字节)
程序头数量：       8
节头大小：         40 (字节)
节头数量：         35
字符串表索引节头： 32

节头：
[Nr] Name              Type            Addr     Off    Size   ES Flg Lk Inf Al
[ 0]                   NULL            00000000 000000 000000 00      0   0 0
[ 1] .interp           PROGBITS        08048134 000134 000013 00   A 0   0 1
[ 2] .note.ABI-tag     NOTE            08048148 000148 000020 00   A 0   0 4
[ 3] .note.SuSE        NOTE            08048168 000168 000018 00   A 0   0 4
[ 4] .hash             HASH            08048180 000180 000030 04   A 5   0 4
[ 5] .dynsym           DYNSYM          080481b0 0001b0 000070 10   A 6   1 4
[ 6] .dynstr           STRTAB          08048220 000220 000066 00   A 0   0 1
[ 7] .gnu.version      VERSYM          08048286 000286 00000e 02   A 5   0 2
[ 8] .gnu.version_r    VERNEED         08048294 000294 000020 00   A 6   1 4
[ 9] .rel.dyn          REL             080482b4 0002b4 000008 08   A 5   0 4
[10] .rel.plt          REL             080482bc 0002bc 000020 08   A 5 12 4
[11] .init             PROGBITS        080482dc 0002dc 000017 00 AX 0   0 4
[12] .plt              PROGBITS        080482f4 0002f4 000050 04 AX 0   0 4
[13] .text             PROGBITS        08048350 000350 00021c 00 AX 0   0 16
[14] .fini             PROGBITS        0804856c 00056c 00001c 00 AX 0   0 4
[15] .rodata           PROGBITS        08048588 000588 000013 00   A 0   0 4
[16] .eh_frame         PROGBITS        0804859c 00059c 000004 00   A 0   0 4
[17] .ctors            PROGBITS        080495a0 0005a0 000008 00 WA 0   0 4
[18] .dtors            PROGBITS        080495a8 0005a8 000008 00 WA 0   0 4
[19] .jcr              PROGBITS        080495b0 0005b0 000004 00 WA 0   0 4
[20] .dynamic          DYNAMIC         080495b4 0005b4 0000c8 08 WA 6   0 4
[21] .got              PROGBITS        0804967c 00067c 000004 04 WA 0   0 4
[22] .got.plt          PROGBITS        08049680 000680 00001c 04 WA 0   0 4
[23] .data             PROGBITS        0804969c 00069c 00000c 00 WA 0   0 4
[24] .bss              NOBITS          080496a8 0006a8 000004 00 WA 0   0 4
[25] .comment          PROGBITS        00000000 0006a8 000117 00      0   0 1
[26] .debug_aranges    PROGBITS        00000000 0007c0 000058 00      0   0 8
[27] .debug_pubnames   PROGBITS        00000000 000818 000025 00      0   0 1
[28] .debug_info       PROGBITS        00000000 00083d 000191 00      0   0 1
[29] .debug_abbrev     PROGBITS        00000000 0009ce 000062 00      0   0 1
[30] .debug_line       PROGBITS        00000000 000a30 000137 00      0   0 1
[31] .debug_str        PROGBITS        00000000 000b67 0000a5 01 MS 0   0 1
[32] .shstrtab         STRTAB          00000000 000c0c 000132 00      0   0 1
[33] .symtab           SYMTAB          00000000 0012b8 000570 10     34 65 4
[34] .strtab           STRTAB          00000000 001828 0002d9 00      0   0 1
Key to Flags:
W (write), A (alloc), X (execute), M (merge), S (strings)
I (info), L (link order), G (group), x (unknown)
O (extra OS processing required) o (OS specific), p (processor specific)

There are no section groups in this file.

程序头：
Type           Offset   VirtAddr   PhysAddr   FileSiz MemSiz Flg Align
PHDR           0x000034 0x08048034 0x08048034 0x00100 0x00100 R E 0x4
INTERP         0x000134 0x08048134 0x08048134 0x00013 0x00013 R   0x1
      [正在请求程序解释器：/lib/ld-linux.so.2]
LOAD           0x000000 0x08048000 0x08048000 0x005a0 0x005a0 R E 0x1000
LOAD           0x0005a0 0x080495a0 0x080495a0 0x00108 0x0010c RW 0x1000
DYNAMIC        0x0005b4 0x080495b4 0x080495b4 0x000c8 0x000c8 RW 0x4
NOTE           0x000148 0x08048148 0x08048148 0x00020 0x00020 R   0x4
NOTE           0x000168 0x08048168 0x08048168 0x00018 0x00018 R   0x4
GNU_STACK      0x000000 0x00000000 0x00000000 0x00000 0x00000 RW 0x4

Section to Segment mapping:
段节...
   00
   01     .interp
   02     .interp .note.ABI-tag .note.SuSE .hash .dynsym .dynstr .gnu.version .gnu.version_r .rel.dyn .rel.plt .init .plt .text .fini .rodata .eh_frame
   03     .ctors .dtors .jcr .dynamic .got .got.plt .data .bss
   04     .dynamic
   05     .note.ABI-tag
   06     .note.SuSE
   07

Dynamic section at offset 0x5b4 contains 20 entries:
标记        类型                         名称/值
0x00000001 (NEEDED)                     共享库：[libc.so.6]
0x0000000c (INIT)                       0x80482dc
0x0000000d (FINI)                       0x804856c
0x00000004 (HASH)                       0x8048180
0x00000005 (STRTAB)                     0x8048220
0x00000006 (SYMTAB)                     0x80481b0
0x0000000a (STRSZ)                      102 (bytes)
0x0000000b (SYMENT)                     16 (bytes)
0x00000015 (DEBUG)                      0x0
0x00000003 (PLTGOT)                     0x8049680
0x00000002 (PLTRELSZ)                   32 (bytes)
0x00000014 (PLTREL)                     REL
0x00000017 (JMPREL)                     0x80482bc
0x00000011 (REL)                        0x80482b4
0x00000012 (RELSZ)                      8 (bytes)
0x00000013 (RELENT)                     8 (bytes)
0x6ffffffe (VERNEED)                    0x8048294
0x6fffffff (VERNEEDNUM)                 1
0x6ffffff0 (VERSYM)                     0x8048286
0x00000000 (NULL)                       0x0

重定位节 “.rel.dyn” 位于偏移量 0x2b4 含有 1 个条目：
Offset     Info    Type            Sym.Value Sym. Name
0804967c 00000606 R_386_GLOB_DAT    00000000   __gmon_start__

 

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