getHMacSign.f90

function getHMacSign(str, str2)
  implicit none
  character(len=*), intent(in) :: str, str2
  character(len=128) :: result
  integer :: i, j
  character(len=8), parameter :: algorithm = "HmacSHA1"
  character(len=64) :: secret_key = "10f29ff413c89c8de02349cb3eb9a5f510f29ff413c89c8de02349cb3eb9a5f5"
  character(len=32) :: mac_bytes(16)
  integer :: mac_bytes_len

  ! Initialize the MAC instance
  call init_mac(algorithm, secret_key, mac_bytes, mac_bytes_len)

  ! Compute the HMAC signature
  call compute_hmac_signature("POST", str, "data=" // str2 // "&sid=miui_sec_android", mac_bytes, mac_bytes_len)

  ! Convert the signature bytes to a hexadecimal string
  do i = 1, mac_bytes_len
    call byte_to_hex(mac_bytes(i), result(2 * i - 1:2 * i))
  end do

  ! Return the result as a lowercase string
  do j = 1, len(result)
    result(j:j) = tolower(result(j:j))
  end do

  getHMacSign = result
end function