Merge pull request 'Fix ipv4 port extraction; Fix ipv6 presentation; Implement Display for PacketInfo' (#4) from fix-port-parse into main

Reviewed-on: https://codeberg.org/NamelessTeam/nsc/pulls/4

src/sniffing/headers.rs

@@ -1,4 +1,5 @@
 use tun::Error;
+use std::fmt;
 
 // Here we will recieve bytes and try to get their destanation & apply Rules for them.
 use crate::config::Config;
@@ -9,8 +10,15 @@ pub enum Protocol {
     UDP,
     Unsupported(u8)
 }
+type SourceV4Ip = Ipv4;
+type SourceV6Ip = Ipv6;
+#[derive(PartialEq, Debug)]
+pub enum IpVersion {
+    V4,
+    V6
+}
 type Ipv4 = [u8; 4];
-type Ipv6 = [u8; 16];
+type Ipv6 = [u16; 8];
 type Port = u16;
 #[derive(Debug, PartialEq)]
 pub enum PacketInfo {
@@ -34,7 +42,70 @@ pub enum PacketInfo {
     }
 }
 
+impl fmt::Display for PacketInfo {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        if self.version() == &IpVersion::V4 {
+             let src_ip = self.src_ipv4_ip().unwrap();
+             let dst_ip = self.dst_ipv4_ip().unwrap();
+             write!(f, "{}.{}.{}.{}:{} -> {}.{}.{}.{}:{} {:?} is dns? {:?}", src_ip[0], src_ip[1], src_ip[2], src_ip[3], self.src_port(), dst_ip[0], dst_ip[1], dst_ip[2], dst_ip[3], self.dst_port(), self.protocol(), self.dns())
+        } else {
+             let src_ip = self.src_ipv6_ip().unwrap();
+             let dst_ip = self.dst_ipv6_ip().unwrap();
+            // y:y:y:y:y:y:y:y = 8 hexademical; y = segment, pair of 2 u8 big endian
+             write!(f, "{:x}:{:x}:{:x}:{:x}:{:x}:{:x}:{:x}:{:x} port:{} -> {:x}:{:x}:{:x}:{:x}:{:x}:{:x}:{:x}:{:x} port:{} {:?} is dns? {:?}", src_ip[0], src_ip[1], src_ip[2], src_ip[3], src_ip[4], src_ip[5], src_ip[6], src_ip[7], self.src_port(), dst_ip[0], dst_ip[1], dst_ip[2], dst_ip[3], dst_ip[4], dst_ip[5], dst_ip[6], dst_ip[7], self.dst_port(), self.protocol(), self.dns())
+        }
+    }
+}
+
 impl PacketInfo {
+    pub fn dns(&self) -> &bool {
+        match self {
+            PacketInfo::V4 { dns, ..} => dns,
+            PacketInfo::V6 { dns, ..} => dns,
+        }
+    }
+    pub fn src_ipv6_ip(&self) -> Option<&SourceV6Ip> {
+        match self {
+            PacketInfo::V6 { src_ip, .. } => Some(src_ip),
+            _ => None
+        }
+    }
+    pub fn dst_ipv6_ip(&self) -> Option<&SourceV6Ip> {
+        match self {
+            PacketInfo::V6 { dst_ip, .. } => Some(dst_ip),
+            _ => None
+        }
+    }
+    pub fn src_ipv4_ip(&self) -> Option<&SourceV4Ip> {
+        match self {
+            PacketInfo::V4 { src_ip, .. } => Some(src_ip),
+            _ => None,
+        }
+    }
+    pub fn dst_ipv4_ip(&self) -> Option<&SourceV4Ip> {
+        match self {
+            PacketInfo::V4 { dst_ip, .. } => Some(dst_ip),
+            _ => None
+        }
+    }
+    pub fn src_port(&self) -> &Port {
+        match self {
+            PacketInfo::V4 { src_port, .. } => src_port,
+            PacketInfo::V6 { src_port, .. } => src_port
+        }
+    }
+    pub fn dst_port(&self) -> &Port {
+        match self {
+            PacketInfo::V4 { dst_port, .. } => dst_port,
+            PacketInfo::V6 { dst_port, .. } => dst_port
+        }
+    }
+    pub fn version(&self) -> &IpVersion {
+        match self {
+            PacketInfo::V4 { .. }=> &IpVersion::V4,
+            PacketInfo::V6 { .. }=> &IpVersion::V6
+        }
+    }
     pub fn protocol(&self) -> &Protocol {
         match self {
             PacketInfo::V4 { protocol, .. } => protocol,
@@ -52,13 +123,14 @@ pub fn sniff_raw_packets(packet: &Packet) -> SniffedPacket {
     let ver = packet[0] >> 4;
     match ver {
         4 => {
-            let dst_port = Port::from_be_bytes([packet[22], packet[23]]);
+            // Internet Header Length (IHL).
+            let ihl = (packet[0] & 0x0F) as usize * 4;
+            let dst_port = Port::from_be_bytes([packet[ihl+2], packet[ihl+3]]);
             let dns;
             if dst_port == 53 { dns = true; } else { dns = false; };
-            // FIXME: hardcoded IPv4 port offset
             let v4 = PacketInfo::V4{
                 src_ip: <Ipv4>::try_from(&packet[12..16])?,
-                src_port: Port::from_be_bytes([packet[20], packet[21]]),
+                src_port: Port::from_be_bytes([packet[ihl], packet[ihl+1]]),
                 dst_ip: <Ipv4>::try_from(&packet[16..20])?,
                 dst_port,
                 protocol: match packet[9] {
@@ -69,7 +141,7 @@ pub fn sniff_raw_packets(packet: &Packet) -> SniffedPacket {
                 dns
             };
         if !matches!(v4.protocol(), Protocol::Unsupported(_)) {
-            println!("{v4:?}");
+            println!("{v4}");
         } else {
             // TODO: make --debug option which will include this diagnostic, for general use this
                 // should be off
@@ -78,13 +150,17 @@ pub fn sniff_raw_packets(packet: &Packet) -> SniffedPacket {
             Ok(v4)
         },
         6 => {
-            let dst_port = Port::from_be_bytes([packet[22], packet[23]]);
+            // y:y:y:y:y:y:y:y hexademical; y = segment, pair of 2 u8 in big endian
+            let src_ip = std::array::from_fn(|i| u16::from_be_bytes([packet[8 + i*2], packet[8 + i*2 + 1]]));
+            let dst_ip = std::array::from_fn(|i| u16::from_be_bytes([packet[24 + i*2], packet[24 + i*2 + 1]]));
+
+            let dst_port = Port::from_be_bytes([packet[42], packet[43]]);
             let dns;
             if dst_port == 53 { dns = true; } else { dns = false; };
             let v6 = PacketInfo::V6{
-                src_ip: <Ipv6>::try_from(&packet[8..24])?,
+                src_ip,
                 src_port: Port::from_be_bytes([packet[40], packet[41]]),
-                dst_ip: <Ipv6>::try_from(&packet[24..40])?,
+                dst_ip,
                 dst_port,
                 protocol: match packet[6] {
                     6 => Protocol::TCP,
@@ -94,7 +170,7 @@ pub fn sniff_raw_packets(packet: &Packet) -> SniffedPacket {
                 dns
             };
         if !matches!(v6.protocol(), Protocol::Unsupported(_)) {
-            println!("{v6:?}");
+            println!("{v6}");
         } else {
             // TODO: make --debug option which will include this diagnostic, for general use this
                 // should be off