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lib32: add .dynstr and .text sections
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@mewmew
mewmew committed Mar 19, 2019
1 parent a855b54 commit 3fc4757
Showing 1 changed file with 109 additions and 67 deletions.
176 changes: 109 additions & 67 deletions lib_elf32.asm
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Original file line number Diff line number Diff line change
Expand Up @@ -176,7 +176,30 @@ db 0x01, 0x00, 0x00, 0x00, 0x89, 0x73, 0x88, 0x0b, 0x00, 0x00, 0x00, 0x00, 0x00,
; 00000130
db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x00 ; |................|
; 00000140
db 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x05, 0x00, 0x00, 0x66, 0x6f, 0x6f, 0x00 ; |.........foo.|
db 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x05, 0x00

; 00000140

; --- [ .dynstr section ] ------------------------------------------------------

dynstr_off equ $ - BASE_R_SEG

; 000001a8

dynstr:

.null:
db 0

.foo:
db "foo", 0

.null_off equ .null - dynstr ; 0
.foo_off equ .foo - dynstr ; 1

dynstr.size equ $ - dynstr

; --- [/ .dynstr section ] -----------------------------------------------------

r_seg.size equ $ - r_seg

Expand All @@ -192,8 +215,21 @@ x_seg_off equ r_seg_off + round(r_seg.size, PAGE)

x_seg:

; --- [ .text section ] --------------------------------------------------------

text_off equ x_seg_off

; 00001000
db 0xb8, 0x2a, 0x00, 0x00, 0x00, 0xc3 ; |.*....|

text:

.start:
mov eax, 42
ret

text.size equ $ - text

; --- [/ .text section ] -------------------------------------------------------

x_seg.size equ $ - x_seg

Expand All @@ -209,7 +245,18 @@ rdata_seg_off equ x_seg_off + round(x_seg.size, PAGE)

rdata_seg:

; .rdata segment contains no data.
; --- [ .eh_frame section ] ----------------------------------------------------

eh_frame_off equ rdata_seg_off

; 00002000

eh_frame:
; no data

eh_frame.size equ $ - eh_frame

; --- [/ .eh_frame section ] ---------------------------------------------------

rdata_seg.size equ $ - rdata_seg

Expand Down Expand Up @@ -270,8 +317,6 @@ gnu_hash equ 0x108 ; TODO: remove
; Tag Type Name/Value
; 0x00000005 (STRTAB) 0x148

dynstr equ 0x148 ; TODO: remove

.strtab:
dd DT_STRTAB ; tag: Entry type.
dd dynstr ; val: Integer/Address value.
Expand All @@ -288,8 +333,6 @@ dynsym equ 0x128 ; TODO: remove
; Tag Type Name/Value
; 0x0000000a (STRSZ) 5 (bytes)

dynstr.size equ 5 ; TODO: remove

.strsz:
dd DT_STRSZ ; tag: Entry type.
dd dynstr.size ; val: Integer/Address value.
Expand Down Expand Up @@ -354,6 +397,8 @@ shstrtab:

shstrtab.size equ $ - shstrtab

; --- [/ .shstrtab section ] ---------------------------------------------------

align 0x4, db 0x00

; === [ Section headers ] ======================================================
Expand Down Expand Up @@ -401,7 +446,6 @@ shdr:
gnu_hash equ 0x108 ; TODO: remove
gnu_hash_off equ 0x108 ; TODO: remove
gnu_hash.size equ 0x20 ; TODO: remove
gnu_hash_link equ 2 ; TODO: remove
gnu_hash.entsize equ 4 ; TODO: remove

.gnu_hash:
Expand All @@ -411,7 +455,7 @@ gnu_hash.entsize equ 4 ; TODO: remove
dd gnu_hash ; addr: Address in memory image.
dd gnu_hash_off ; off: Offset in file.
dd gnu_hash.size ; size: Size in bytes.
dd gnu_hash_link ; link: Index of a related section.
dd shdr.dynsym_idx ; link: Index of a related section.
dd 0 ; info: Depends on section type.
dd 0x4 ; addralign: Alignment in bytes.
dd gnu_hash.entsize ; entsize: Size of each entry in section.
Expand All @@ -422,8 +466,6 @@ gnu_hash.entsize equ 4 ; TODO: remove
dynsym equ 0x128 ; TODO: remove
dynsym_off equ 0x128 ; TODO: remove
dynsym.size equ 0x20 ; TODO: remove
dynsym_link equ 3 ; TODO: remove
dynsym_info equ 1 ; TODO: remove
dynsym.entsize equ 0x10 ; TODO: remove

.dynsym:
Expand All @@ -433,18 +475,14 @@ dynsym.entsize equ 0x10 ; TODO: remove
dd dynsym ; addr: Address in memory image.
dd dynsym_off ; off: Offset in file.
dd dynsym.size ; size: Size in bytes.
dd dynsym_link ; link: Index of a related section.
dd dynsym_info ; info: Depends on section type.
dd shdr.dynstr_idx ; link: Index of a related section.
dd shdr.gnu_hash_idx ; info: Depends on section type.
dd 0x4 ; addralign: Alignment in bytes.
dd dynsym.entsize ; entsize: Size of each entry in section.

; [Nr] Name Type Addr Off Size ES Flg Lk Inf Al
; [ 3] .dynstr STRTAB 00000148 000148 000005 00 A 0 0 1

dynstr equ 0x148 ; TODO: remove
dynstr_off equ 0x148 ; TODO: remove
dynstr.size equ 5 ; TODO: remove

.dynstr:
dd shstrtab.dynstr_idx ; name: Section name (index into the section header string table).
dd SHT_STRTAB ; type: Section type.
Expand All @@ -460,69 +498,73 @@ dynstr.size equ 5 ; TODO: remove
; [Nr] Name Type Addr Off Size ES Flg Lk Inf Al
; [ 4] .text PROGBITS 00001000 001000 000006 00 AX 0 0 16

text equ 0x1000 ; TODO: remove
text_off equ 0x1000 ; TODO: remove
text.size equ 6 ; TODO: remove

.text:
dd shstrtab.text_idx ; name: Section name (index into the section header string table).
dd SHT_PROGBITS ; type: Section type.
dd SHF_ALLOC | SHF_EXECINSTR ; flags: Section flags.
dd text ; addr: Address in memory image.
dd text_off ; off: Offset in file.
dd text.size ; size: Size in bytes.
dd 0 ; link: Index of a related section.
dd 0 ; info: Depends on section type.
dd 0x10 ; addralign: Alignment in bytes.
dd 0 ; entsize: Size of each entry in section.
dd shstrtab.text_idx ; name: Section name (index into the section header string table).
dd SHT_PROGBITS ; type: Section type.
dd SHF_ALLOC | SHF_EXECINSTR ; flags: Section flags.
dd text ; addr: Address in memory image.
dd text_off ; off: Offset in file.
dd text.size ; size: Size in bytes.
dd 0 ; link: Index of a related section.
dd 0 ; info: Depends on section type.
dd 0x10 ; addralign: Alignment in bytes.
dd 0 ; entsize: Size of each entry in section.

; [Nr] Name Type Addr Off Size ES Flg Lk Inf Al
; [ 5] .eh_frame PROGBITS 00002000 002000 000000 00 A 0 0 4

eh_frame equ 0x2000 ; TODO: remove
eh_frame_off equ 0x2000 ; TODO: remove
eh_frame.size equ 0 ; TODO: remove

.eh_frame:
dd shstrtab.eh_frame_idx ; name: Section name (index into the section header string table).
dd SHT_PROGBITS ; type: Section type.
dd SHF_ALLOC ; flags: Section flags.
dd eh_frame ; addr: Address in memory image.
dd eh_frame_off ; off: Offset in file.
dd eh_frame.size ; size: Size in bytes.
dd 0 ; link: Index of a related section.
dd 0 ; info: Depends on section type.
dd 0x4 ; addralign: Alignment in bytes.
dd 0 ; entsize: Size of each entry in section.
dd shstrtab.eh_frame_idx ; name: Section name (index into the section header string table).
dd SHT_PROGBITS ; type: Section type.
dd SHF_ALLOC ; flags: Section flags.
dd eh_frame ; addr: Address in memory image.
dd eh_frame_off ; off: Offset in file.
dd eh_frame.size ; size: Size in bytes.
dd 0 ; link: Index of a related section.
dd 0 ; info: Depends on section type.
dd 0x4 ; addralign: Alignment in bytes.
dd 0 ; entsize: Size of each entry in section.

; [Nr] Name Type Addr Off Size ES Flg Lk Inf Al
; [ 6] .dynamic DYNAMIC 00002fa0 002fa0 000060 08 WA 3 0 4

dynamic_link equ 3 ; TODO: remove

.dynamic:
dd shstrtab.dynamic_idx ; name: Section name (index into the section header string table).
dd SHT_DYNAMIC ; type: Section type.
dd SHF_WRITE | SHF_ALLOC ; flags: Section flags.
dd dynamic ; addr: Address in memory image.
dd dynamic_off ; off: Offset in file.
dd dynamic.size ; size: Size in bytes.
dd dynamic_link ; link: Index of a related section.
dd 0 ; info: Depends on section type.
dd 0x4 ; addralign: Alignment in bytes.
dd dynamic.entsize ; entsize: Size of each entry in section.
dd shstrtab.dynamic_idx ; name: Section name (index into the section header string table).
dd SHT_DYNAMIC ; type: Section type.
dd SHF_WRITE | SHF_ALLOC ; flags: Section flags.
dd dynamic ; addr: Address in memory image.
dd dynamic_off ; off: Offset in file.
dd dynamic.size ; size: Size in bytes.
dd shdr.dynstr_idx ; link: Index of a related section.
dd 0 ; info: Depends on section type.
dd 0x4 ; addralign: Alignment in bytes.
dd dynamic.entsize ; entsize: Size of each entry in section.

; [Nr] Name Type Addr Off Size ES Flg Lk Inf Al
; [ 7] .shstrtab STRTAB 00000000 003000 00003e 00 0 0 1

.shstrtab:
dd shstrtab.shstrtab_idx ; name: Section name (index into the section header string table).
dd SHT_STRTAB ; type: Section type.
dd 0x0 ; flags: Section flags.
dd 0 ; addr: Address in memory image.
dd shstrtab_off ; off: Offset in file.
dd shstrtab.size ; size: Size in bytes.
dd 0 ; link: Index of a related section.
dd 0 ; info: Depends on section type.
dd 0x1 ; addralign: Alignment in bytes.
dd 0 ; entsize: Size of each entry in section.
dd shstrtab.shstrtab_idx ; name: Section name (index into the section header string table).
dd SHT_STRTAB ; type: Section type.
dd 0x0 ; flags: Section flags.
dd 0 ; addr: Address in memory image.
dd shstrtab_off ; off: Offset in file.
dd shstrtab.size ; size: Size in bytes.
dd 0 ; link: Index of a related section.
dd 0 ; info: Depends on section type.
dd 0x1 ; addralign: Alignment in bytes.
dd 0 ; entsize: Size of each entry in section.

.null_idx equ (.null - shdr) / .entsize
.gnu_hash_idx equ (.gnu_hash - shdr) / .entsize
.dynsym_idx equ (.dynsym - shdr) / .entsize
.dynstr_idx equ (.dynstr - shdr) / .entsize
.text_idx equ (.text - shdr) / .entsize
.eh_frame_idx equ (.eh_frame - shdr) / .entsize
.dynamic_idx equ (.dynamic - shdr) / .entsize
.shstrtab_idx equ (.shstrtab - shdr) / .entsize

shdr.size equ $ - shdr
shdr.count equ shdr.size / shdr.entsize

; === [/ Section headers ] =====================================================

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