diff --git a/src/wire/ieee802154.rs b/src/wire/ieee802154.rs index b52a2d9f6..aca402e59 100644 --- a/src/wire/ieee802154.rs +++ b/src/wire/ieee802154.rs @@ -6,45 +6,6 @@ use crate::wire::ipv6::Address as Ipv6Address; use crate::Error; use crate::Result; -const CRC_TABLE: [u16; 256] = [ - 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf, 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, - 0xca6c, 0xdbe5, 0xe97e, 0xf8f7, 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e, - 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876, 0x2102, 0x308b, 0x0210, 0x1399, - 0x6726, 0x76af, 0x4434, 0x55bd, 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5, - 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c, 0xbdcb, 0xac42, 0x9ed9, 0x8f50, - 0xfbef, 0xea66, 0xd8fd, 0xc974, 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb, - 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3, 0x5285, 0x430c, 0x7197, 0x601e, - 0x14a1, 0x0528, 0x37b3, 0x263a, 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72, - 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9, 0xef4e, 0xfec7, 0xcc5c, 0xddd5, - 0xa96a, 0xb8e3, 0x8a78, 0x9bf1, 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738, - 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70, 0x8408, 0x9581, 0xa71a, 0xb693, - 0xc22c, 0xd3a5, 0xe13e, 0xf0b7, 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff, - 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036, 0x18c1, 0x0948, 0x3bd3, 0x2a5a, - 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e, 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5, - 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd, 0xb58b, 0xa402, 0x9699, 0x8710, - 0xf3af, 0xe226, 0xd0bd, 0xc134, 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c, - 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3, 0x4a44, 0x5bcd, 0x6956, 0x78df, - 0x0c60, 0x1de9, 0x2f72, 0x3efb, 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232, - 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a, 0xe70e, 0xf687, 0xc41c, 0xd595, - 0xa12a, 0xb0a3, 0x8238, 0x93b1, 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9, - 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330, 0x7bc7, 0x6a4e, 0x58d5, 0x495c, - 0x3de3, 0x2c6a, 0x1ef1, 0x0f78, -]; - -pub fn calculate_crc(buffer: &[u8]) -> u16 { - fn crc_byte(crc: u16, c: u8) -> u16 { - (crc >> 8) ^ CRC_TABLE[((crc ^ (c as u16)) & 0xff) as usize] - } - - let mut crc = 0; - - for b in buffer { - crc = crc_byte(crc, *b); - } - - crc -} - enum_with_unknown! { /// IEEE 802.15.4 frame type. pub enum FrameType(u8) { @@ -288,7 +249,8 @@ impl> Frame { /// Ensure that no accessor method will panic if called. /// Returns `Err(Error::Truncated)` if the buffer is too short. pub fn check_len(&self) -> Result<()> { - if self.buffer.as_ref().is_empty() { + // We need at least 3 bytes + if self.buffer.as_ref().len() < 3 { Err(Error::Truncated) } else { Ok(()) @@ -476,27 +438,118 @@ impl> Frame { } } - /// Return the Auxilliary Security Header Field - #[inline] - pub fn aux_security_header(&self) -> Option<&[u8]> { - match self.frame_type() { - FrameType::Beacon - | FrameType::Data - | FrameType::MacCommand - | FrameType::Multipurpose => (), - FrameType::Acknowledgement if self.frame_version() == FrameVersion::Ieee802154 => (), - FrameType::Acknowledgement - | FrameType::Extended - | FrameType::FragmentOrFrak - | FrameType::Unknown(_) => return None, + /// Return the index where the auxiliary security header starts. + fn aux_security_header_start(&self) -> usize { + // We start with 3, because 2 bytes for frame control and the sequence number. + let mut index = 3; + index += self.addressing_fields().unwrap().len(); + index + } + + /// Return the index where the payload starts. + fn payload_start(&self) -> usize { + let mut index = self.aux_security_header_start(); + + if self.security_enabled() { + // We add 5 because 1 byte for control bits and 4 bytes for frame counter. + index += 5; + index += if let Some(len) = self.key_identifier_length() { + len as usize + } else { + 0 + }; } - if !self.security_enabled() { - return None; + index + } + + /// Return the lenght of the key identifier field. + fn key_identifier_length(&self) -> Option { + Some(match self.key_identifier_mode() { + 0 => 0, + 1 => 1, + 2 => 5, + 3 => 9, + _ => return None, + }) + } + + /// Return the security level of the auxiliary security header. + pub fn security_level(&self) -> u8 { + let index = self.aux_security_header_start(); + let b = self.buffer.as_ref()[index..][0]; + b & 0b111 + } + + /// Return the key identifier mode used by the auxiliary security header. + pub fn key_identifier_mode(&self) -> u8 { + let index = self.aux_security_header_start(); + let b = self.buffer.as_ref()[index..][0]; + (b >> 3) & 0b11 + } + + /// Return the frame counter field. + pub fn frame_counter(&self) -> u32 { + let index = self.aux_security_header_start(); + let b = &self.buffer.as_ref()[index..]; + LittleEndian::read_u32(&b[1..1 + 4]) + } + + /// Return the Key Identifier field. + fn key_identifier(&self) -> &[u8] { + let index = self.aux_security_header_start(); + let b = &self.buffer.as_ref()[index..]; + let length = if let Some(len) = self.key_identifier_length() { + len as usize + } else { + 0 + }; + &b[5..][..length] + } + + /// Return the Key Source field. + pub fn key_source(&self) -> Option<&[u8]> { + let ki = self.key_identifier(); + let len = ki.len(); + if len > 1 { + Some(&ki[..len - 1]) + } else { + None + } + } + + /// Return the Key Index field. + pub fn key_index(&self) -> Option { + let ki = self.key_identifier(); + let len = ki.len(); + + if len > 0 { + Some(ki[len - 1]) + } else { + None } + } + + /// Return the Message Integrity Code (MIC). + pub fn message_integrity_code(&self) -> Option<&[u8]> { + let mic_len = match self.security_level() { + 0 | 4 => return None, + 1 | 5 => 4, + 2 | 6 => 8, + 3 | 7 => 16, + _ => panic!(), + }; + + let data = &self.buffer.as_ref(); + let len = data.len(); - net_debug!("Auxilliary security header is currently not supported."); - None + Some(&data[len - mic_len..]) + } + + /// Return the MAC header. + pub fn mac_header(&self) -> &[u8] { + let data = &self.buffer.as_ref(); + &data[..self.payload_start()] } } @@ -506,10 +559,10 @@ impl<'a, T: AsRef<[u8]> + ?Sized> Frame<&'a T> { pub fn payload(&self) -> Option<&'a [u8]> { match self.frame_type() { FrameType::Data => { - let data = &self.buffer.as_ref()[field::ADDRESSING]; - let offset = self.addressing_fields().unwrap().len(); + let index = self.payload_start(); + let data = &self.buffer.as_ref(); - Some(&data[offset..]) + Some(&data[index..]) } _ => None, } @@ -652,12 +705,9 @@ impl + AsMut<[u8]>> Frame { pub fn payload_mut(&mut self) -> Option<&mut [u8]> { match self.frame_type() { FrameType::Data => { - let mut start_offset = 3; - start_offset += self.addressing_fields().unwrap().len(); - + let index = self.payload_start(); let data = self.buffer.as_mut(); - let end_offset = start_offset + data.len() - 2; - Some(&mut data[start_offset..end_offset]) + Some(&mut data[index..]) } _ => None, } @@ -892,6 +942,49 @@ mod test { dst_addressing_mode -> AddressingMode::Short, frame_version -> FrameVersion::Ieee802154_2006, src_addressing_mode -> AddressingMode::Extended, - //payload -> Some(&[0x2b, 0x00, 0x00, 0x00]), + payload -> Some(&[0x2b, 0x00, 0x00, 0x00][..]), + } + + vector_test! { + security + [ + 0x69,0xdc, // frame control + 0x32, // sequence number + 0xcd,0xab, // destination PAN id + 0xbf,0x9b,0x15,0x06,0x00,0x4b,0x12,0x00, // extended destination address + 0xc7,0xd9,0xb5,0x14,0x00,0x4b,0x12,0x00, // extended source address + 0x05, // security control field + 0x31,0x01,0x00,0x00, // frame counter + 0x3e,0xe8,0xfb,0x85,0xe4,0xcc,0xf4,0x48,0x90,0xfe,0x56,0x66,0xf7,0x1c,0x65,0x9e,0xf9, // data + 0x93,0xc8,0x34,0x2e,// MIC + ]; + frame_type -> FrameType::Data, + security_enabled -> true, + frame_pending -> false, + ack_request -> true, + pan_id_compression -> true, + dst_addressing_mode -> AddressingMode::Extended, + frame_version -> FrameVersion::Ieee802154_2006, + src_addressing_mode -> AddressingMode::Extended, + dst_pan_id -> Some(Pan(0xabcd)), + dst_addr -> Some(Address::Extended([0x00,0x12,0x4b,0x00,0x06,0x15,0x9b,0xbf])), + src_pan_id -> None, + src_addr -> Some(Address::Extended([0x00,0x12,0x4b,0x00,0x14,0xb5,0xd9,0xc7])), + security_level -> 5, + key_identifier_mode -> 0, + frame_counter -> 305, + key_source -> None, + key_index -> None, + payload -> Some(&[0x3e,0xe8,0xfb,0x85,0xe4,0xcc,0xf4,0x48,0x90,0xfe,0x56,0x66,0xf7,0x1c,0x65,0x9e,0xf9,0x93,0xc8,0x34,0x2e][..]), + message_integrity_code -> Some(&[0x93, 0xC8, 0x34, 0x2E][..]), + mac_header -> &[ + 0x69,0xdc, // frame control + 0x32, // sequence number + 0xcd,0xab, // destination PAN id + 0xbf,0x9b,0x15,0x06,0x00,0x4b,0x12,0x00, // extended destination address + 0xc7,0xd9,0xb5,0x14,0x00,0x4b,0x12,0x00, // extended source address + 0x05, // security control field + 0x31,0x01,0x00,0x00, // frame counter + ][..], } }