[feature] Support IPv4 Options Decodedev-lwp

1 files changed, 101 insertions, 3 deletions

diff --git a/src/protocol/ipv4.rs b/src/protocol/ipv4.rs
index 2297196..f2fc19b 100644
--- a/src/protocol/ipv4.rs
+++ b/src/protocol/ipv4.rs
@@ -45,6 +45,7 @@ pub struct IPv4Header {
     pub checksum: u16,
     pub source_address: Ipv4Addr,
     pub dest_address: Ipv4Addr,
+    pub options: Option<Vec<u8>>,
 }
 
 /******************************************************************************
@@ -84,8 +85,11 @@ impl Decode for IPv4Header {
         let (input, checksum) = number::streaming::be_u16(input)?;
         let (input, source_address) = address_v4_decode(input)?;
         let (input, dest_address) = address_v4_decode(input)?;
-
-        // TODO IPv4 Options Decode
+        let (input, options) = match verihl.1 > 5 {
+            true => nom::bytes::streaming::take((verihl.1 - 5) * 4)(input)
+                .map(|(i, l)| (i, Some(l.to_vec())))?,
+            false => (input, None),
+        };
 
         Ok((
             input,
@@ -102,6 +106,7 @@ impl Decode for IPv4Header {
                 checksum,
                 source_address,
                 dest_address,
+                options,
             },
         ))
     }
@@ -121,7 +126,8 @@ mod tests {
     const LAST_SLICE: &'static [u8] = &[0xff];
 
     #[test]
-    fn ipv4_header_decode() {
+    // Without Options
+    fn ipv4_header_decode1() {
         /*
          * Internet Protocol Version 4, Src: 192.168.0.101, Dst: 121.14.154.93
          *     0100 .... = Version: 4
@@ -173,6 +179,98 @@ mod tests {
             checksum: 0xc352,
             source_address: Ipv4Addr::new(192, 168, 0, 101),
             dest_address: Ipv4Addr::new(121, 14, 154, 93),
+            options: None,
+        };
+
+        assert_eq!(IPv4Header::decode(&bytes), Ok((LAST_SLICE, expectation)));
+
+        // example
+        let result = IPv4Header::decode(&bytes);
+        match result {
+            Ok((payload, header)) => {
+                println!("OK: {:?}, payload: {}", header, payload.len());
+            }
+            Err(e) => {
+                println!("ERR: {:?}", e);
+            }
+        }
+
+        // assert_eq!(1, 0);
+    }
+
+    #[test]
+    // With Options
+    fn ipv4_header_decode2() {
+        /*
+         * Internet Protocol Version 4, Src: 127.0.0.1, Dst: 127.0.0.1
+         *     0100 .... = Version: 4
+         *     .... 1111 = Header Length: 60 bytes (15)
+         *     Differentiated Services Field: 0x00 (DSCP: CS0, ECN: Not-ECT)
+         *         0000 00.. = Differentiated Services Codepoint: Default (0)
+         *         .... ..00 = Explicit Congestion Notification: Not ECN-Capable Transport (0)
+         *     Total Length: 124
+         *     Identification: 0x0000 (0)
+         *     010. .... = Flags: 0x2, Don't fragment
+         *         0... .... = Reserved bit: Not set
+         *         .1.. .... = Don't fragment: Set
+         *         ..0. .... = More fragments: Not set
+         *     ...0 0000 0000 0000 = Fragment Offset: 0
+         *     Time to Live: 64
+         *     Protocol: ICMP (1)
+         *     Header Checksum: 0xfd30 [correct]
+         *     [Header checksum status: Good]
+         *     [Calculated Checksum: 0xfd30]
+         *     Source Address: 127.0.0.1
+         *     Destination Address: 127.0.0.1
+         *     Options: (40 bytes), Commercial Security
+         *         IP Option - Commercial Security (40 bytes)
+         *             Type: 134
+         *                 1... .... = Copy on fragmentation: Yes
+         *                 .00. .... = Class: Control (0)
+         *                 ...0 0110 = Number: Commercial IP security option (6)
+         *             Length: 40
+         *             DOI: 1
+         *             Tag Type: Restrictive Category Bitmap (1)
+         *             Sensitivity Level: 1
+         *             Categories: 0,2,4,5,6,239
+         */
+
+        let bytes = [
+            0x4f, /* Version and Header length */
+            0x00, /* Differentiated Services Field */
+            0x00, 0x7c, /* Total Length */
+            0x00, 0x00, /* Identification */
+            0x40, 0x00, /* Flags and Fragment Offset */
+            0x40, /* Time to Live */
+            0x01, /* Protocol */
+            0xfd, 0x30, /* Header Checksum */
+            0x7f, 0x00, 0x00, 0x01, /* Source Address */
+            0x7f, 0x00, 0x00, 0x01, /* Destination Address */
+            0x86, 0x28, 0x00, 0x00, 0x00, 0x01, 0x01, 0x22, 0x00, 0x01, 0xae, 0x00, 0x00, 0x00,
+            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+            0x01, /* Options */
+            0xff, /* Payload */
+        ];
+
+        let expectation = IPv4Header {
+            version: 4,
+            ihl: 60,
+            tos: 0,
+            length: 124,
+            id: 0x0000,
+            flags: 0x2,
+            frag_offset: 0,
+            ttl: 64,
+            protocol: IPProtocol::ICMP,
+            checksum: 0xfd30,
+            source_address: Ipv4Addr::new(127, 0, 0, 1),
+            dest_address: Ipv4Addr::new(127, 0, 0, 1),
+            options: Some(vec![
+                0x86, 0x28, 0x00, 0x00, 0x00, 0x01, 0x01, 0x22, 0x00, 0x01, 0xae, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
+            ]),
         };
 
         assert_eq!(IPv4Header::decode(&bytes), Ok((LAST_SLICE, expectation)));