user: What would the C source look like for the assembly code provided here?

```asm
<onion_decode_block>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x10,%rsp
  mov    %rdi,-0x8(%rbp)
  mov    %rsi,-0x10(%rbp)
  mov    -0x10(%rbp),%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <onion_value@plt>
  shl    $0x3,%eax
  and    $0xfffffff8,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x10(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <onion_value@plt>
  sar    $0x2,%eax
  and    $0x7,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  movzbl (%rax),%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  or     %ecx,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  mov    %dl,(%rax)
  mov    -0x10(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <onion_value@plt>
  shl    $0x6,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  add    $0x1,%rax
  and    $0xffffffc0,%edx
  mov    %dl,(%rax)
  mov    -0x10(%rbp),%rax
  add    $0x2,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <onion_value@plt>
  add    %eax,%eax
  and    $0x3e,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  or     %eax,%ecx
  mov    %ecx,%edx
  mov    -0x8(%rbp),%rax
  add    $0x1,%rax
  mov    %dl,(%rax)
  mov    -0x10(%rbp),%rax
  add    $0x3,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <onion_value@plt>
  sar    $0x4,%eax
  and    $0x1,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  add    $0x1,%rax
  movzbl (%rax),%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  or     %eax,%ecx
  mov    %ecx,%edx
  mov    -0x8(%rbp),%rax
  add    $0x1,%rax
  mov    %dl,(%rax)
  mov    -0x10(%rbp),%rax
  add    $0x3,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <onion_value@plt>
  shl    $0x4,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  add    $0x2,%rax
  and    $0xfffffff0,%edx
  mov    %dl,(%rax)
  mov    -0x10(%rbp),%rax
  add    $0x4,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <onion_value@plt>
  sar    %eax
  and    $0xf,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  add    $0x2,%rax
  movzbl (%rax),%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  or     %eax,%ecx
  mov    %ecx,%edx
  mov    -0x8(%rbp),%rax
  add    $0x2,%rax
  mov    %dl,(%rax)
  mov    -0x10(%rbp),%rax
  add    $0x4,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <onion_value@plt>
  shl    $0x7,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  add    $0x3,%rax
  and    $0xffffff80,%edx
  mov    %dl,(%rax)
  mov    -0x10(%rbp),%rax
  add    $0x5,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <onion_value@plt>
  shl    $0x2,%eax
  and    $0x7c,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  add    $0x3,%rax
  movzbl (%rax),%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  or     %eax,%ecx
  mov    %ecx,%edx
  mov    -0x8(%rbp),%rax
  add    $0x3,%rax
  mov    %dl,(%rax)
  mov    -0x10(%rbp),%rax
  add    $0x6,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <onion_value@plt>
  sar    $0x3,%eax
  and    $0x3,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  add    $0x3,%rax
  movzbl (%rax),%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  or     %eax,%ecx
  mov    %ecx,%edx
  mov    -0x8(%rbp),%rax
  add    $0x3,%rax
  mov    %dl,(%rax)
  mov    -0x10(%rbp),%rax
  add    $0x6,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <onion_value@plt>
  shl    $0x5,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  add    $0x4,%rax
  and    $0xffffffe0,%edx
  mov    %dl,(%rax)
  mov    -0x10(%rbp),%rax
  add    $0x7,%rax
  movzbl (%rax),%eax
  movzbl %al,%eax
  mov    %eax,%edi
  call   <onion_value@plt>
  and    $0x1f,%eax
  mov    %eax,%edx
  mov    -0x8(%rbp),%rax
  add    $0x4,%rax
  movzbl (%rax),%eax
  mov    %eax,%ecx
  mov    %edx,%eax
  or     %eax,%ecx
  mov    %ecx,%edx
  mov    -0x8(%rbp),%rax
  add    $0x4,%rax
  mov    %dl,(%rax)
  nop
  leave
  ret
```

assistant: ```c
void onion_decode_block(unsigned char *dst, const unsigned char *src) {
  dst[0] = onion_value(src[0]) << 3 & 0xf8;
  dst[0] |= onion_value(src[1]) >> 2 & 0x07;
  dst[1] = onion_value(src[1]) << 6 & 0xc0;
  dst[1] |= onion_value(src[2]) << 1 & 0x3e;
  dst[1] |= onion_value(src[3]) >> 4 & 0x01;
  dst[2] = onion_value(src[3]) << 4 & 0xf0;
  dst[2] |= onion_value(src[4]) >> 1 & 0x0f;
  dst[3] = onion_value(src[4]) << 7 & 0x80;
  dst[3] |= onion_value(src[5]) << 2 & 0x7c;
  dst[3] |= onion_value(src[6]) >> 3 & 0x3;
  dst[4] = onion_value(src[6]) << 5 & 0xe0;
  dst[4] |= onion_value(src[7]) & 0x1f;
}
```