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woody-woodpacker
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Merge branch 'debug-double-packing'

This commit is contained in:
gbrochar 2024-04-17 09:02:51 +02:00
parent d1c86e7165 c04078e5a2
commit d7668b88a8
5 changed files with 16 additions and 11 deletions
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1
gen_payload.sh Executable file
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@ -0,0 +1 @@
nasm -f elf64 -o print.o print.s && ld -o print print.o && nasm -f bin -o payload print.s && hexdump -v -e '"\\\x\" 1/1 "%02x"' payload

1
includes/woody.h
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@ -49,3 +49,4 @@ int prepare_injection(t_elf_content *woody);
void encrypt(char *file, unsigned long int offset, unsigned long int size);
#endif

5
print.s
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@ -9,7 +9,7 @@ _start:
mov rdi, 1
lea rsi, [rel msg]
mov rdx, 10
mov rdx, 14
mov rax, 1
syscall
pop rdx
@ -17,6 +17,7 @@ _start:
pop rdi
pop rax
jmp 0x00000000
msg db "..WOODY..",10
msg db "....WOODY....",10
text_section dq 0xbabababababababa
section_sisze dq 0xcacacacacacacaca

1
srcs/main.c
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@ -43,3 +43,4 @@ int main(int ac, char **av)
return ret;
return prepare_injection(&woody);
}

7
srcs/woody.c
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@ -1,6 +1,5 @@
#include "../includes/woody.h"
int elf_magic_numbers(char *str)
{
return (!ft_strncmp(str, ELFMAG, SELFMAG));
@ -111,7 +110,7 @@ int insert_payload(t_elf_content *woody, t_payload *payload, size_t payload_posi
printf("the jump = %ld\n", payload->len - 16);
int32_t jmp_index = ptr_jmp - payload->payload;
int32_t jump_value = (payload_position - woody->Ehdr->e_entry + jmp_index - 1) * -1;
int32_t jump_value = ((payload_position + jmp_index + 5) - woody->Ehdr->e_entry) * -1; // 5 = JUMP SIZE (OPCODE + 4 bytes operand)
ft_memcpy(&payload->payload[jmp_index + 1], &jump_value, sizeof(jump_value));
int64_t text_index = ptr_text_section - payload->payload;
@ -127,7 +126,7 @@ int insert_payload(t_elf_content *woody, t_payload *payload, size_t payload_posi
printf("Old entry : %ld (%lx)\n", woody->Ehdr->e_entry, woody->Ehdr->e_entry);
printf("Code cave start = %ld (%lx)\n", payload_position, payload_position);
printf("Payload size = %ld (%lx)\n", payload->len, payload->len);
printf("Backwar d offset = %d (%x)(%x)\n", jump_value, jump_value, -jump_value);
printf("Backward offset = %d (%x)(%x)\n", jump_value, jump_value, -jump_value);
return EXIT_SUCCESS;
}
return EXIT_FAILURE;
@ -205,6 +204,7 @@ int get_elf_sections(t_elf_content *woody)
break;
}
}
return EXIT_SUCCESS;
}
@ -224,3 +224,4 @@ int prepare_injection(t_elf_content *woody)
free(woody_file);
return EXIT_SUCCESS;
}