user: 这段汇编代码用C语言表示是什么样的？

```asm
<tls1_prf>:
  endbr64
  push   %r15
  mov    %rdx,%r15
  push   %r14
  mov    %r8d,%r14d
  push   %r13
  mov    %rdi,%r13
  mov    %rdx,%rdi
  push   %r12
  movslq %esi,%r12
  push   %rbp
  push   %rbx
  mov    %r9,%rbx
  sub    $0xe8,%rsp
  mov    %rcx,(%rsp)
  mov    %fs:0x28,%rax
  mov    %rax,0xd8(%rsp)
  xor    %eax,%eax
  call   <strlen@plt>
  lea    0x14(%r14,%rax,1),%eax
  cmp    $0x80,%eax
  ja     L125
  lea    0x1(%r12),%eax
  mov    %r15,%rdi
  mov    %r13,0x8(%rsp)
  mov    %eax,%ebp
  shr    $0x1f,%ebp
  add    %eax,%ebp
  sar    %ebp
  movslq %ebp,%rax
  sub    %rax,%r12
  add    %r13,%r12
  mov    %r12,0x18(%rsp)
  lea    0x50(%rsp),%r12
  call   <strlen@plt>
  mov    %r15,%rsi
  lea    0x54(%rsp),%r15
  mov    %eax,%r13d
  lea    0x64(%rsp),%rax
  mov    %rax,%rdi
  mov    %rax,0x10(%rsp)
  mov    %r13d,%edx
  xor    %eax,%eax
  call   <memcpy@plt>
  mov    (%rsp),%rsi
  movslq %r13d,%rax
  mov    %r14d,%edx
  lea    0x14(%r12,%rax,1),%rdi
  xor    %eax,%eax
  add    %r13d,%r14d
  call   <memcpy@plt>
  mov    0x10(%rsp),%rdx
  mov    %r15,%r8
  mov    %r14d,%ecx
  mov    0x8(%rsp),%rdi
  mov    %ebp,%esi
  mov    %r14d,0x24(%rsp)
  call   <md5_hmac@plt>
  mov    0x120(%rsp),%eax
  test   %eax,%eax
  jle    L145
  lea    0x10(%r14),%eax
  lea    0x30(%rsp),%r13
  mov    %rbx,%r14
  mov    $0xf,%r10d
  mov    %eax,0x20(%rsp)
  mov    0x120(%rsp),%eax
  mov    %rbx,0x28(%rsp)
  mov    0x8(%rsp),%rbx
  sub    $0x1,%eax
  mov    %r12,0x8(%rsp)
  mov    %r15,%r12
  mov    %r14,%r15
  and    $0xfffffff0,%eax
  mov    %r13,%r14
  mov    %r10d,%r13d
  add    $0x1f,%eax
  mov    %eax,(%rsp)
  jmp    L148
  nopl   (%rax)
L26:
  and    $0x4,%ecx
  jne    L194
  test   %eax,%eax
  je     L182
  movzbl (%r14),%ecx
  mov    %cl,(%r15)
  test   $0x2,%al
  jne    L164
L182:
  add    $0x10,%r13d
  add    $0x10,%r15
  cmp    (%rsp),%r13d
  je     L102
L148:
  mov    0x20(%rsp),%ecx
  mov    %r14,%r8
  mov    %r12,%rdx
  mov    %ebp,%esi
  mov    %rbx,%rdi
  call   <md5_hmac@plt>
  mov    %r12,%r8
  mov    $0x10,%ecx
  mov    %r12,%rdx
  mov    %ebp,%esi
  mov    %rbx,%rdi
  call   <md5_hmac@plt>
  mov    $0x10,%eax
  cmp    %r13d,0x120(%rsp)
  jle    L71
L111:
  movslq %eax,%rcx
  test   %eax,%eax
  mov    $0x1,%eax
  cmovle %rax,%rcx
  mov    %ecx,%eax
  cmp    $0x8,%ecx
  jb     L26
  mov    (%r14),%rax
  lea    0x8(%r15),%rdi
  mov    %r14,%r8
  and    $0xfffffffffffffff8,%rdi
  mov    %rax,(%r15)
  mov    %ecx,%eax
  mov    -0x8(%r14,%rax,1),%rsi
  mov    %rsi,-0x8(%r15,%rax,1)
  mov    %r15,%rax
  sub    %rdi,%rax
  sub    %rax,%r8
  add    %ecx,%eax
  and    $0xfffffff8,%eax
  cmp    $0x8,%eax
  jb     L182
  and    $0xfffffff8,%eax
  xor    %ecx,%ecx
L89:
  mov    %ecx,%edx
  add    $0x8,%ecx
  mov    (%r8,%rdx,1),%rsi
  mov    %rsi,(%rdi,%rdx,1)
  cmp    %eax,%ecx
  jb     L89
  add    $0x10,%r13d
  add    $0x10,%r15
  cmp    (%rsp),%r13d
  jne    L148
L102:
  mov    0x8(%rsp),%r12
  mov    0x24(%rsp),%r15d
  mov    %ebp,%esi
  mov    %r14,%r13
  mov    0x10(%rsp),%rdx
  mov    0x18(%rsp),%rdi
  mov    %r12,%r8
  mov    %r15d,%ecx
  mov    0x28(%rsp),%rbx
  add    $0x14,%r15d
  call   <sha1_hmac@plt>
  mov    0x120(%rsp),%eax
  mov    0x120(%rsp),%edx
  mov    %r15d,(%rsp)
  movslq 0x120(%rsp),%r14
  mov    %r12,%r15
  sar    $0x1f,%eax
  imul   $0x66666667,%r14,%r14
  sar    $0x23,%r14
  sub    %eax,%r14d
  lea    (%r14,%r14,4),%eax
  xor    %r14d,%r14d
  shl    $0x2,%eax
  mov    %r14d,%r12d
  mov    %ebp,%r14d
  mov    0x18(%rsp),%rbp
  sub    %eax,%edx
  mov    %r13,%rax
  mov    %rbx,%r13
  mov    %edx,0x20(%rsp)
  mov    %rax,%rbx
  nopw   0x0(%rax,%rax,1)
L214:
  mov    (%rsp),%ecx
  mov    %rbx,%r8
  mov    %r15,%rdx
  mov    %r14d,%esi
  mov    %rbp,%rdi
  call   <sha1_hmac@plt>
  mov    %r14d,%esi
  mov    %r15,%r8
  mov    $0x14,%ecx
  mov    %r15,%rdx
  mov    %rbp,%rdi
  call   <sha1_hmac@plt>
  lea    0x13(%r12),%eax
  mov    $0x14,%esi
  cmp    0x120(%rsp),%eax
  jge    L104
L206:
  xor    %eax,%eax
  nopl   0x0(%rax,%rax,1)
L98:
  movzbl (%rbx,%rax,1),%ecx
  xor    %cl,0x0(%r13,%rax,1)
  add    $0x1,%rax
  cmp    %eax,%esi
  jg     L98
L122:
  add    $0x14,%r12d
  add    $0x14,%r13
  cmp    %r12d,0x120(%rsp)
  jg     L214
  mov    %rbx,%r13
  mov    %r15,%r12
L66:
  mov    $0x80,%edx
  xor    %esi,%esi
  mov    %r12,%rdi
  call   <memset@plt>
  mov    $0x14,%edx
  xor    %esi,%esi
  mov    %r13,%rdi
  call   <memset@plt>
  xor    %eax,%eax
L163:
  mov    0xd8(%rsp),%rdx
  sub    %fs:0x28,%rdx
  jne    L13
  add    $0xe8,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopw   0x0(%rax,%rax,1)
L71:
  mov    0x120(%rsp),%eax
  and    $0xf,%eax
  jne    L111
  jmp    L182
  nopl   (%rax)
L104:
  mov    0x20(%rsp),%eax
  mov    %eax,%esi
  test   %eax,%eax
  jne    L206
  jmp    L122
L194:
  mov    (%r14),%ecx
  mov    %ecx,(%r15)
  mov    -0x4(%r14,%rax,1),%ecx
  mov    %ecx,-0x4(%r15,%rax,1)
  jmp    L182
L164:
  movzwl -0x2(%r14,%rax,1),%ecx
  mov    %cx,-0x2(%r15,%rax,1)
  jmp    L182
L145:
  mov    0x24(%rsp),%ecx
  mov    0x10(%rsp),%rdx
  mov    %r12,%r8
  mov    %ebp,%esi
  mov    0x18(%rsp),%rdi
  lea    0x30(%rsp),%r13
  call   <sha1_hmac@plt>
  jmp    L66
L125:
  mov    $0xffffe800,%eax
  jmp    L163
L13:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
int tls1_prf(unsigned char *secret, int slen, char *label, unsigned char *random, int rlen, unsigned char *dstbuf, int dlen) {
  int nb, hs;
  int i, j, k;
  unsigned char *S1, *S2;
  unsigned char tmp[128];
  unsigned char h_i[20];
  if (sizeof(tmp) < 20 + strlen(label) + rlen)
    return (-0x1800);
  hs = (slen + 1) / 2;
  S1 = secret;
  S2 = secret + slen - hs;
  nb = strlen(label);
  memcpy(tmp + 20, label, nb);
  memcpy(tmp + 20 + nb, random, rlen);
  nb += rlen;
  md5_hmac(S1, hs, tmp + 20, nb, 4 + tmp);
  for (i = 0; i < dlen; i += 16) {
    md5_hmac(S1, hs, 4 + tmp, 16 + nb, h_i);
    md5_hmac(S1, hs, 4 + tmp, 16, 4 + tmp);
    k = (i + 16 > dlen) ? dlen % 16 : 16;
    for (j = 0; j < k; j++)
      dstbuf[i + j] = h_i[j];
  }
  sha1_hmac(S2, hs, tmp + 20, nb, tmp);
  for (i = 0; i < dlen; i += 20) {
    sha1_hmac(S2, hs, tmp, 20 + nb, h_i);
    sha1_hmac(S2, hs, tmp, 20, tmp);
    k = (i + 20 > dlen) ? dlen % 20 : 20;
    for (j = 0; j < k; j++)
      dstbuf[i + j] = (unsigned char)(dstbuf[i + j] ^ h_i[j]);
  }
  memset(tmp, 0, sizeof(tmp));
  memset(h_i, 0, sizeof(h_i));
  return (0);
}
```