调整项目结构、尝试支持安卓

switch/packet/src/icmp/icmp.rs

@@ -0,0 +1,174 @@
+use std::fmt;
+
+use byteorder::{BigEndian, ReadBytesExt};
+
+use crate::cal_checksum;
+use crate::error::*;
+/// icmp 协议
+/*  https://www.rfc-editor.org/rfc/rfc792
+   0                   1                   2                   3
+   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+  |     Type      |     Code      |          Checksum             |
+  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+  |                      不同Type和Code有不同含义                    |
+  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+  |                 数据体 不同Type和Code有不同含义                    |
+  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+*/
+use crate::icmp::{Code, Kind};
+use crate::ip::ipv4::packet::IpV4Packet;
+
+pub struct IcmpPacket<B> {
+    buffer: B,
+}
+
+impl<B: AsRef<[u8]>> IcmpPacket<B> {
+    pub fn unchecked(buffer: B) -> Self {
+        Self { buffer }
+    }
+    pub fn new(buffer: B) -> Result<Self> {
+        if buffer.as_ref().len() < 8 {
+            Err(Error::SmallBuffer)?
+        }
+        let packet = Self::unchecked(buffer);
+        Ok(packet)
+    }
+}
+
+impl<B: AsRef<[u8]> + AsMut<[u8]>> IcmpPacket<B> {
+    pub fn set_kind(&mut self, kind: Kind) {
+        self.buffer.as_mut()[0] = kind.into();
+    }
+    pub fn update_checksum(&mut self) {
+        self.buffer.as_mut()[2..4].copy_from_slice(&[0, 0]);
+        let checksum = cal_checksum(self.buffer.as_ref());
+        self.buffer.as_mut()[2..4].copy_from_slice(&checksum.to_be_bytes());
+    }
+}
+
+impl<B: AsRef<[u8]>> IcmpPacket<B> {
+    pub fn kind(&self) -> Kind {
+        Kind::from(self.buffer.as_ref()[0])
+    }
+    pub fn code(&self) -> Code {
+        Code::from(self.kind(), self.buffer.as_ref()[1])
+    }
+    pub fn checksum(&self) -> u16 {
+        (&self.buffer.as_ref()[2..])
+            .read_u16::<BigEndian>()
+            .unwrap()
+    }
+    pub fn is_valid(&self) -> bool {
+        self.checksum() == 0 || cal_checksum(self.buffer.as_ref()) == 0
+    }
+    pub fn header_other(&self) -> HeaderOther {
+        match self.kind() {
+            Kind::EchoReply
+            | Kind::EchoRequest
+            | Kind::TimestampRequest
+            | Kind::TimestampReply
+            | Kind::InformationRequest
+            | Kind::InformationReply => {
+                let ide = (&self.buffer.as_ref()[4..])
+                    .read_u16::<BigEndian>()
+                    .unwrap();
+                let seq = (&self.buffer.as_ref()[6..])
+                    .read_u16::<BigEndian>()
+                    .unwrap();
+                HeaderOther::Identifier(ide, seq)
+            }
+            Kind::DestinationUnreachable | Kind::TimeExceeded | Kind::SourceQuench => {
+                let bytes = self.buffer.as_ref();
+                HeaderOther::Unused(bytes[4], bytes[5], bytes[6], bytes[7])
+            }
+            Kind::Redirect => {
+                let bytes = self.buffer.as_ref();
+                HeaderOther::Address(bytes[4], bytes[5], bytes[6], bytes[7])
+            }
+            Kind::ParameterProblem => HeaderOther::Pointer(self.buffer.as_ref()[4]),
+            _ => {
+                let bytes = self.buffer.as_ref();
+                HeaderOther::UnKnown(bytes[4], bytes[5], bytes[6], bytes[7])
+            }
+        }
+    }
+    pub fn payload(&self) -> &[u8] {
+        &self.buffer.as_ref()[8..]
+    }
+    pub fn description(&self) -> Description<&[u8]> {
+        use std::io::Cursor;
+        match self.kind() {
+            Kind::DestinationUnreachable
+            | Kind::TimeExceeded
+            | Kind::ParameterProblem
+            | Kind::SourceQuench
+            | Kind::Redirect => match IpV4Packet::new(self.payload()) {
+                Ok(d) => Description::Ip(d),
+                Err(_) => Description::Other(self.payload()),
+            },
+            Kind::TimestampRequest | Kind::TimestampReply => {
+                let mut buffer = Cursor::new(self.payload());
+                Description::Timestamp(
+                    buffer.read_u32::<BigEndian>().unwrap(),
+                    buffer.read_u32::<BigEndian>().unwrap(),
+                    buffer.read_u32::<BigEndian>().unwrap(),
+                )
+            }
+            _ => Description::Other(self.payload()),
+        }
+    }
+}
+
+impl<B: AsRef<[u8]>> fmt::Debug for IcmpPacket<B> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct(if self.is_valid() {
+            "icmp::Packet"
+        } else {
+            "icmp::Packet!"
+        })
+        .field("kind", &self.kind())
+        .field("code", &self.code())
+        .field("checksum", &self.checksum())
+        .field("payload", &self.payload())
+        .finish()
+    }
+}
+
+#[derive(Debug)]
+pub enum HeaderOther {
+    /// 全零
+    Unused(u8, u8, u8, u8),
+    /// If code = 0, identifies the octet where an error was detected.
+    Pointer(u8),
+    /// Address of the gateway to which traffic for the network specified
+    ///       in the internet destination network field of the original
+    ///       datagram's data should be sent.
+    Address(u8, u8, u8, u8),
+    ///      Identifier          |        Sequence Number
+    Identifier(u16, u16),
+    UnKnown(u8, u8, u8, u8),
+}
+
+pub enum Description<B> {
+    Ip(IpV4Packet<B>),
+    ///时间戳  Originate Timestamp,Receive Timestamp,Transmit Timestamp
+    Timestamp(u32, u32, u32),
+    Other(B),
+}
+
+impl<B: AsRef<[u8]> + std::fmt::Debug> fmt::Debug for Description<B> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Description::Ip(packet) => f.debug_struct(&format!("{:?}", packet)).finish(),
+            Description::Timestamp(originate, receive, transmit) => f
+                .debug_struct("")
+                .field("originate", originate)
+                .field("receive", receive)
+                .field("transmit", transmit)
+                .finish(),
+            Description::Other(bytes) => f.debug_struct(&format!("{:?}", bytes)).finish(),
+        }
+    }
+}