From 41fb358473e52233b99225597be23265311d0f09 Mon Sep 17 00:00:00 2001
From: pbonilla <pbonilla@student.42.fr>
Date: Wed, 17 Apr 2024 12:14:08 +0200
Subject: [PATCH] start rot 1

---
 includes/woody.h |  2 ++
 print.s          | 18 ++++++++++++++++--
 srcs/encrypt.c   |  2 +-
 srcs/woody.c     | 18 ++++++++++--------
 4 files changed, 29 insertions(+), 11 deletions(-)

diff --git a/includes/woody.h b/includes/woody.h
index 2807779..459e691 100644
--- a/includes/woody.h
+++ b/includes/woody.h
@@ -14,7 +14,9 @@
 #include <elf.h>
 #include <stdint.h>
 
+
 #define JUMP "\xe9"
+#define WOODY "..WOODY.."
 #define TEXT_OFFSET "\xba\xba\xba\xba\xba\xba\xba\xba"
 #define SECTION_SIZE "\xca\xca\xca\xca\xca\xca\xca\xca"
 
diff --git a/print.s b/print.s
index 519afa7..51adbe6 100644
--- a/print.s
+++ b/print.s
@@ -9,7 +9,20 @@ _start:
 
 		mov rdi, 1
 		lea     rsi, [rel msg]
-		mov byte[rsi - 317], 0x90
+		mov rax, rsi
+		sub rax, qword [rel text_section] ;text_section address
+		mov r8, qword [rel section_sisze] ;text_section size
+		mov r9, 0 ;increment register
+		xor r10, r10
+	; encrypt:
+	; 	cmp r8, r9
+	; 	je end_encrypt
+	; 	mov r10b, byte[rax + r9]
+	; 	inc r10b ;rot + 1
+	; 	mov byte[rax + r9], r10b
+	; 	inc r9
+	; 	jmp encrypt
+	; end_encrypt:
 		mov rdx, 10
 		mov rax, 1
 		syscall
@@ -17,7 +30,8 @@ _start:
         pop rsi
         pop rdi
         pop rax
-        jmp 0x00000000
+
+        jmp 0x00000000 ;for now it needs to be the first jmp
 		msg     db "..WOODY..",10
 		text_section      dq 0xbabababababababa
 		section_sisze     dq 0xcacacacacacacaca
\ No newline at end of file
diff --git a/srcs/encrypt.c b/srcs/encrypt.c
index 833b63a..f7866d7 100644
--- a/srcs/encrypt.c
+++ b/srcs/encrypt.c
@@ -5,7 +5,7 @@ void	encrypt(char *file, unsigned long int offset, unsigned long int size)
 	size_t i = 0;
 	while (i < size)
 	{
-		file[offset + i] = file[offset + i] + 1;
+		file[offset + i] = file[offset + i] - 1;
 		++i;
 	}
 }
\ No newline at end of file
diff --git a/srcs/woody.c b/srcs/woody.c
index 21176da..37b3ecd 100644
--- a/srcs/woody.c
+++ b/srcs/woody.c
@@ -101,29 +101,31 @@ t_payload *get_payload()
 int	insert_payload(t_elf_content *woody, t_payload *payload, size_t payload_position)
 {
 	char *ptr_jmp = ft_strnstr_nullterminated(payload->payload, JUMP, payload->len);
+	char *ptr_woody = ft_strnstr_nullterminated(payload->payload, WOODY, payload->len);
 	char *ptr_text_section = ft_strnstr_nullterminated(payload->payload, TEXT_OFFSET, payload->len);
 	char *ptr_section_size = ft_strnstr_nullterminated(payload->payload, SECTION_SIZE, payload->len);
-	if (ptr_jmp && ptr_text_section && ptr_section_size)
+	if (ptr_jmp && ptr_woody && ptr_text_section && ptr_section_size)
 	{
-		printf("test a jumo = %ld\n", ptr_jmp - payload->payload);
-		printf("test a jumo = %ld\n", ptr_jmp - payload->payload + sizeof(JUMP));
-		printf("jump base = %ld\n", payload->len);
-		printf("the jump = %ld\n", payload->len - 16);
+		int32_t woody_index = ptr_woody - payload->payload;
 
 		int32_t jmp_index = ptr_jmp - payload->payload;
 		int32_t jump_value = (payload_position - woody->Ehdr->e_entry + jmp_index - 1) * -1;
 		ft_memcpy(&payload->payload[jmp_index + 1], &jump_value, sizeof(jump_value));
 
 		int64_t text_index = ptr_text_section - payload->payload;
-		int64_t text_value = (payload_position - woody->text_section->sh_offset + text_index - 1) * -1;
-		text_value = 0;
+		int64_t text_value = payload_position - woody->Ehdr->e_entry + woody_index;
 		ft_memcpy(&payload->payload[text_index], &text_value, sizeof(text_value));
 		
 		int64_t section_index = ptr_section_size - payload->payload;
-		int64_t section_value = (payload_position - woody->text_section->sh_size + section_index - 1) * -1;
+		int64_t section_value = woody->text_section->sh_size;
 		ft_memcpy(&payload->payload[section_index], &section_value, sizeof(section_value));
 
 		ft_memcpy(woody->file + payload_position, payload->payload, payload->len);
+		
+		printf("jmp_index : %d (%x)\n", jmp_index, jmp_index);
+		printf("woody index :%d (%x)\n", woody_index, woody_index);
+		printf("jmp_index++ : %ld (%lx)\n", jmp_index + sizeof(JUMP) + sizeof(jump_value), jmp_index + sizeof(JUMP) + sizeof(jump_value) - 1);
+		printf("text_value : %ld (%lx)\n", text_value, text_value);
 		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);