use crate::NetEaseCryptoError; use aes::Aes128Dec; use cipher::block_padding::Pkcs7; use cipher::generic_array::GenericArray; use cipher::{BlockDecrypt, KeyInit}; use itertools::Itertools; use umc_utils::base64; const METADATA_KEY: [u8; 0x10] = *b"#14ljk_!\\]&0U<'("; /// Decrypt metadata /// /// # Arguments /// /// * `key`: Encrypted metadata /// /// returns: Result, NetEaseCryptoError> pub fn decrypt(enciphered_metadata: T) -> Result, NetEaseCryptoError> where T: AsRef<[u8]>, { let data = enciphered_metadata .as_ref() .iter() .map(|&b| b ^ 0x63) .collect_vec(); let data = match data.strip_prefix(b"163 key(Don't modify):") { None => Err(NetEaseCryptoError::MetadataWrongPrefix( String::from_utf8_lossy(&data[..]).to_string(), ))?, Some(data) => data, }; let mut data = base64::decode(data).map_err(NetEaseCryptoError::MetadataDecodeError)?; let aes = Aes128Dec::new(&GenericArray::from(METADATA_KEY)); let metadata = aes .decrypt_padded::(&mut data[..]) .map_err(NetEaseCryptoError::MetadataDecryptError)?; let metadata = match metadata.strip_prefix(b"music:") { None => Err(NetEaseCryptoError::MetadataInvalidJsonPrefix( String::from_utf8_lossy(metadata).to_string(), ))?, Some(stripped) => stripped, }; Ok(Vec::from(metadata)) } #[test] fn test_decrypt_metadata() -> Result<(), NetEaseCryptoError> { let enciphered_metadata = [ 0x52, 0x55, 0x50, 0x43, 0x08, 0x06, 0x1A, 0x4B, 0x27, 0x0C, 0x0D, 0x44, 0x17, 0x43, 0x0E, 0x0C, 0x07, 0x0A, 0x05, 0x1A, 0x4A, 0x59, 0x2F, 0x55, 0x57, 0x25, 0x36, 0x50, 0x34, 0x57, 0x3A, 0x1B, 0x3B, 0x50, 0x39, 0x25, 0x37, 0x0E, 0x01, 0x39, 0x48, 0x5B, 0x4C, 0x05, 0x09, 0x07, 0x2B, 0x55, 0x22, 0x00, 0x48, 0x31, 0x32, 0x4C, 0x17, 0x07, 0x0D, 0x24, 0x1A, 0x39, 0x11, 0x26, 0x5A, 0x15, 0x29, 0x24, 0x50, 0x02, 0x07, 0x20, 0x56, 0x2D, 0x33, 0x5A, 0x0C, 0x10, 0x29, 0x26, 0x22, 0x28, 0x4C, 0x1A, 0x0D, 0x0B, 0x06, 0x28, 0x0D, 0x2C, 0x1B, 0x09, 0x2E, 0x0B, 0x2B, 0x28, 0x02, 0x13, 0x0F, 0x2F, 0x2C, 0x0E, 0x25, 0x1B, 0x4C, 0x2B, 0x52, 0x33, 0x36, 0x09, 0x37, 0x2D, 0x0B, 0x25, 0x27, 0x2C, 0x0C, 0x0D, 0x02, 0x51, 0x35, 0x5A, 0x1A, 0x35, 0x2D, 0x2F, 0x3B, 0x54, 0x2A, 0x0D, 0x4C, 0x2B, 0x16, 0x1B, 0x0C, 0x26, 0x21, 0x0B, 0x52, 0x25, 0x52, 0x36, 0x5B, 0x51, 0x50, 0x56, 0x01, 0x0A, 0x19, 0x14, 0x5B, 0x57, 0x32, 0x07, 0x06, 0x50, 0x25, 0x55, 0x54, 0x53, 0x30, 0x2C, 0x32, 0x52, 0x15, 0x00, 0x50, 0x37, 0x39, 0x28, 0x0E, 0x15, 0x0F, 0x36, 0x48, 0x11, 0x24, 0x33, 0x56, 0x07, 0x22, 0x20, 0x29, 0x14, 0x28, 0x06, 0x16, 0x01, 0x54, 0x48, 0x0B, 0x17, 0x20, 0x25, 0x36, 0x02, 0x01, 0x16, 0x07, 0x27, 0x16, 0x0C, 0x37, 0x20, 0x2A, 0x24, 0x21, 0x22, 0x50, 0x56, 0x0E, 0x34, 0x52, 0x37, 0x14, 0x29, 0x10, 0x32, 0x20, 0x36, 0x2D, 0x52, 0x21, 0x02, 0x09, 0x3B, 0x0B, 0x01, 0x17, 0x00, 0x33, 0x36, 0x0D, 0x01, 0x21, 0x2B, 0x17, 0x4C, 0x39, 0x02, 0x33, 0x51, 0x02, 0x20, 0x07, 0x37, 0x4C, 0x5A, 0x25, 0x39, 0x09, 0x51, 0x25, 0x50, 0x54, 0x4C, 0x19, 0x32, 0x37, 0x08, 0x06, 0x32, 0x55, 0x1B, 0x53, 0x0B, 0x0B, 0x4C, 0x08, 0x16, 0x33, 0x54, 0x27, 0x11, 0x02, 0x1A, 0x30, 0x28, 0x57, 0x25, 0x50, 0x3B, 0x2E, 0x28, 0x34, 0x51, 0x3B, 0x36, 0x11, 0x53, 0x12, 0x56, 0x09, 0x21, 0x2B, 0x2C, 0x14, 0x2D, 0x24, 0x5A, 0x02, 0x53, 0x16, 0x21, 0x29, 0x16, 0x02, 0x53, 0x02, 0x2A, 0x31, 0x2D, 0x31, 0x56, 0x3B, 0x17, 0x51, 0x52, 0x0F, 0x56, 0x50, 0x56, 0x00, 0x17, 0x57, 0x2F, 0x08, 0x1A, 0x52, 0x25, 0x12, 0x2D, 0x48, 0x05, 0x02, 0x37, 0x0F, 0x36, 0x30, 0x05, 0x14, 0x5A, 0x37, 0x5A, 0x50, 0x55, 0x16, 0x09, 0x53, 0x3B, 0x1B, 0x24, 0x1A, 0x1A, 0x21, 0x50, 0x06, 0x37, 0x2E, 0x57, 0x09, 0x39, 0x17, 0x13, 0x26, 0x31, 0x04, 0x52, 0x50, 0x55, 0x10, 0x53, 0x52, 0x57, 0x02, 0x04, 0x02, 0x2F, 0x01, 0x5A, 0x02, 0x2A, 0x2F, 0x19, 0x4C, 0x0C, 0x55, 0x00, 0x50, 0x2D, 0x29, 0x06, 0x16, 0x11, 0x20, 0x0D, 0x01, 0x53, 0x22, 0x32, 0x1B, 0x34, 0x00, 0x0A, 0x06, 0x02, 0x15, 0x0F, 0x25, 0x5A, 0x1A, 0x22, 0x11, 0x0E, 0x21, 0x32, 0x31, 0x22, 0x39, 0x56, 0x5A, 0x09, 0x16, 0x35, 0x16, 0x30, 0x29, 0x0F, 0x30, 0x27, 0x2C, 0x55, 0x52, 0x12, 0x48, 0x16, 0x0F, 0x0C, 0x36, 0x0C, 0x25, 0x27, 0x28, 0x35, 0x0A, 0x1A, 0x06, 0x09, 0x16, 0x39, 0x1B, 0x08, 0x10, 0x27, 0x12, 0x2C, 0x2C, 0x5B, 0x48, 0x01, 0x48, 0x33, 0x48, 0x0E, 0x1B, 0x54, 0x1B, 0x02, 0x36, 0x25, 0x20, 0x48, 0x31, 0x0B, 0x06, 0x0D, 0x15, 0x11, 0x17, 0x01, 0x24, 0x20, 0x27, 0x31, 0x30, 0x22, 0x0F, 0x22, 0x08, 0x17, 0x0F, 0x13, 0x0C, 0x0C, 0x1A, 0x12, 0x12, 0x51, 0x4C, 0x3B, 0x53, 0x3B, 0x37, 0x39, 0x16, 0x25, 0x05, 0x54, 0x10, 0x32, 0x0D, 0x48, 0x0C, 0x50, 0x5B, 0x20, 0x0B, 0x19, 0x22, 0x19, 0x0D, 0x0B, 0x28, 0x2C, 0x0B, 0x05, 0x3B, 0x51, 0x09, 0x54, 0x0A, 0x06, 0x0F, 0x57, 0x08, 0x51, 0x50, 0x24, 0x29, 0x16, 0x57, 0x33, 0x36, 0x15, 0x04, 0x50, 0x5B, 0x2F, 0x51, 0x56, 0x12, 0x09, 0x2F, 0x27, 0x30, 0x51, 0x2B, 0x37, 0x57, 0x24, 0x35, 0x5B, 0x0C, 0x0E, 0x0D, 0x0D, 0x53, 0x2A, 0x25, 0x06, 0x33, 0x22, 0x29, 0x51, 0x24, 0x08, 0x51, 0x3A, 0x06, 0x0E, 0x16, 0x31, 0x36, 0x2B, 0x10, 0x34, 0x30, 0x08, 0x0A, 0x2F, 0x19, 0x32, 0x5A, 0x04, 0x39, 0x52, 0x36, 0x1A, 0x26, 0x14, 0x0E, 0x0B, 0x2A, 0x4C, 0x39, 0x56, 0x1A, 0x01, 0x2F, 0x14, 0x33, 0x33, 0x56, 0x16, 0x25, 0x29, 0x33, 0x0E, 0x0B, 0x2D, 0x1A, 0x11, 0x29, 0x08, 0x15, 0x02, 0x2B, 0x4C, 0x01, 0x0C, 0x07, 0x0F, 0x15, 0x4C, 0x36, 0x36, 0x09, 0x4C, 0x13, 0x53, 0x11, 0x11, 0x12, 0x02, 0x0F, 0x11, 0x56, 0x2B, 0x5B, 0x21, 0x29, 0x0B, 0x51, 0x09, 0x02, 0x3B, 0x11, 0x02, 0x24, 0x16, 0x12, 0x04, 0x0A, 0x37, 0x0B, 0x22, 0x5A, 0x0B, 0x02, 0x0A, 0x02, 0x36, 0x36, 0x2A, 0x29, 0x1A, 0x14, 0x14, 0x13, 0x1B, 0x2C, 0x11, 0x31, 0x2A, 0x4C, 0x28, 0x11, 0x2B, 0x1B, 0x30, 0x51, 0x35, 0x11, 0x53, 0x0D, 0x09, 0x0F, 0x39, 0x0F, 0x25, 0x17, 0x02, 0x5B, 0x1A, 0x39, 0x26, 0x5B, 0x51, 0x3B, 0x2E, 0x04, 0x2E, 0x21, 0x36, 0x04, 0x3B, 0x11, 0x56, 0x0A, 0x2E, 0x2D, 0x1A, 0x27, 0x21, 0x10, 0x07, 0x53, 0x11, 0x37, 0x07, 0x2F, 0x51, 0x57, 0x2B, 0x24, 0x57, 0x01, 0x53, 0x35, 0x52, 0x0F, 0x2F, 0x2D, 0x48, 0x52, 0x56, 0x2B, 0x00, 0x17, 0x1A, 0x39, 0x00, 0x12, 0x09, 0x02, 0x07, 0x02, 0x52, 0x2C, 0x20, 0x4C, 0x39, 0x4C, 0x48, 0x50, 0x0D, 0x0F, 0x15, 0x4C, 0x00, 0x2B, 0x0F, 0x37, 0x48, 0x19, 0x17, 0x32, 0x35, 0x31, 0x28, 0x0B, 0x0D, 0x2D, 0x32, 0x10, 0x32, 0x56, 0x33, 0x28, 0x3B, 0x2B, 0x55, 0x12, 0x04, 0x07, 0x50, 0x24, 0x00, 0x08, 0x01, 0x10, 0x26, 0x30, 0x2C, 0x34, 0x10, 0x21, 0x0D, 0x25, 0x02, 0x2E, 0x53, 0x11, 0x2B, 0x19, 0x36, 0x31, 0x2E, 0x5A, 0x52, 0x33, 0x35, 0x20, 0x14, 0x53, 0x30, 0x04, 0x05, 0x08, 0x34, 0x13, 0x02, 0x54, 0x22, 0x05, 0x5A, 0x01, 0x20, 0x13, 0x14, 0x39, 0x2A, 0x25, 0x1B, 0x37, 0x48, 0x57, 0x53, 0x2A, 0x22, 0x3A, 0x00, 0x34, 0x53, 0x24, 0x12, ]; let key = decrypt(enciphered_metadata)?; assert_eq!(key[0], b'{'); Ok(()) }