user: Demonstrate the C code that generates the assembly output below:

```asm
<challenge11>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x50,%rsp
  mov    %rdi,-0x48(%rbp)
  mov    %fs:0x28,%rax
  mov    %rax,-0x8(%rbp)
  xor    %eax,%eax
  lea    D68(%rip),%rax
  mov    %rax,%rdi
  call   <puts@plt>
  mov    $0x0,%edi
  call   <time@plt>
  mov    %eax,%edi
  call   <srand@plt>
  mov    -0x48(%rbp),%rax
  mov    %rax,%rdi
  call   <strlen@plt>
  mov    %eax,-0x1c(%rbp)
  movl   $0x0,-0x24(%rbp)
  movl   $0x0,-0x2c(%rbp)
  movl   $0x0,-0x28(%rbp)
  movl   $0x0,-0x20(%rbp)
  jmp    L17
L30:
  lea    -0x34(%rbp),%rcx
  lea    -0x30(%rbp),%rdx
  mov    -0x1c(%rbp),%esi
  mov    -0x48(%rbp),%rax
  mov    %rax,%rdi
  call   <encryption_oracle@plt>
  mov    %rax,-0x10(%rbp)
  mov    -0x34(%rbp),%edx
  mov    -0x10(%rbp),%rax
  mov    %edx,%esi
  mov    %rax,%rdi
  call   <detect_mode@plt>
  mov    %eax,-0x14(%rbp)
  mov    -0x30(%rbp),%eax
  test   %eax,%eax
  jne    L46
  addl   $0x1,-0x2c(%rbp)
  jmp    L5
L46:
  addl   $0x1,-0x28(%rbp)
L5:
  mov    -0x30(%rbp),%eax
  cmp    %eax,-0x14(%rbp)
  jne    L2
  addl   $0x1,-0x24(%rbp)
L2:
  mov    -0x10(%rbp),%rax
  mov    %rax,%rdi
  call   <free@plt>
  addl   $0x1,-0x20(%rbp)
L17:
  cmpl   $0x63,-0x20(%rbp)
  jle    L30
  pxor   %xmm1,%xmm1
  cvtsi2ssl -0x2c(%rbp),%xmm1
  movss  D94(%rip),%xmm0
  mulss  %xmm1,%xmm0
  movss  D94(%rip),%xmm1
  divss  %xmm1,%xmm0
  movss  %xmm0,-0x18(%rbp)
  pxor   %xmm2,%xmm2
  cvtss2sd -0x18(%rbp),%xmm2
  movq   %xmm2,%rax
  movq   %rax,%xmm0
  lea    D80(%rip),%rax
  mov    %rax,%rdi
  mov    $0x1,%eax
  call   <printf@plt>
  pxor   %xmm1,%xmm1
  cvtsi2ssl -0x28(%rbp),%xmm1
  movss  D94(%rip),%xmm0
  mulss  %xmm1,%xmm0
  movss  D94(%rip),%xmm1
  divss  %xmm1,%xmm0
  movss  %xmm0,-0x18(%rbp)
  pxor   %xmm3,%xmm3
  cvtss2sd -0x18(%rbp),%xmm3
  movq   %xmm3,%rax
  movq   %rax,%xmm0
  lea    D35(%rip),%rax
  mov    %rax,%rdi
  mov    $0x1,%eax
  call   <printf@plt>
  pxor   %xmm1,%xmm1
  cvtsi2ssl -0x24(%rbp),%xmm1
  movss  D94(%rip),%xmm0
  mulss  %xmm1,%xmm0
  movss  D94(%rip),%xmm1
  divss  %xmm1,%xmm0
  movss  %xmm0,-0x18(%rbp)
  pxor   %xmm4,%xmm4
  cvtss2sd -0x18(%rbp),%xmm4
  movq   %xmm4,%rax
  movq   %rax,%xmm0
  lea    D63(%rip),%rax
  mov    %rax,%rdi
  mov    $0x1,%eax
  call   <printf@plt>
  nop
  mov    -0x8(%rbp),%rax
  sub    %fs:0x28,%rax
  je     L21
  call   <__stack_chk_fail@plt>
L21:
  leave
  ret
```

tool_calls: name: read_data
arguments: tag: D68
type: string
name: read_data
arguments: tag: D94
type: byte[4]
name: read_data
arguments: tag: D80
type: string
name: read_data
arguments: tag: D35
type: string
name: read_data
arguments: tag: D63
type: string

tool: D68: *** Challenge 11: An ECB/CBC detection oracle

tool: {"D94": [0x00,0x00,0xc8,0x42]}

tool: D80: ECB encryption rate: %.0f%%


tool: D35: CBC encryption rate: %.0f%%


tool: D63: Detection success rate: %.0f%%


assistant: ```c
void challenge11(char *str) {
  uint8_t *enc;
  int out_len;
  int real;
  int detected;
  int num_ecb;
  int num_cbc;
  int successes;
  int len;
  int i;
  float percentage;
  printf("*** Challenge 11: An ECB/CBC detection oracle\n");
  srand(time(NULL));
  len = strlen(str);
  successes = 0;
  num_ecb = 0;
  num_cbc = 0;
  for (i = 0; i < 100; i++) {
    enc = encryption_oracle((uint8_t *)str, len, &real, &out_len);
    detected = detect_mode(enc, out_len);
    if (real == 0)
      num_ecb++;
    else
      num_cbc++;
    if (real == detected)
      successes++;
    free(enc);
  }
  percentage = 100 * (float)num_ecb / 100;
  printf("ECB encryption rate: %.0f%%\n", percentage);
  percentage = 100 * (float)num_cbc / 100;
  printf("CBC encryption rate: %.0f%%\n", percentage);
  percentage = 100 * (float)successes / 100;
  printf("Detection success rate: %.0f%%\n", percentage);
}
```