Add small fix after testing with ping.

src/icmpd/error.rs

@@ -1,8 +1,8 @@
-use std::result;
-use std::fmt;
-use syscall::error::Error as SyscallError;
-use std::io::Error as IOError;
 use std::convert;
+use std::fmt;
+use std::io::Error as IOError;
+use std::result;
+use syscall::error::Error as SyscallError;
 
 pub enum PacketError {
     NotEnoughData,

src/icmpd/main.rs

@@ -18,6 +18,10 @@ mod scheme;
 fn run() -> Result<()> {
     use syscall::flag::*;
 
+    if unsafe { syscall::clone(0).unwrap() } != 0 {
+        return Ok(());
+    }
+
     let icmp_fd = syscall::open("ip:1", O_RDWR | O_NONBLOCK)
         .map_err(|e| Error::from_syscall_error(e, "failed to open ip:1"))? as
                   RawFd;
@@ -26,9 +30,6 @@ fn run() -> Result<()> {
         .map_err(|e| Error::from_syscall_error(e, "failed to open :icmp"))? as
                     RawFd;
 
-    if unsafe { syscall::clone(0).unwrap() } != 0 {
-        return Ok(());
-    }
 
     let icmpd = Rc::new(RefCell::new(Icmpd::new(unsafe { File::from_raw_fd(icmp_fd) },
                                                 unsafe { File::from_raw_fd(scheme_fd) })));

src/icmpd/packet.rs

@@ -13,7 +13,7 @@ pub struct Header {
 #[repr(packed)]
 pub struct EchoHeader {
     id: u16,
-    seq: u16,
+    //Seq is set by the caller
 }
 
 pub enum SubHeader<'a> {
@@ -43,20 +43,15 @@ pub enum PacketKind {
 }
 
 impl EchoHeader {
-    pub fn new(id: u16, seq: u16) -> EchoHeader {
+    pub fn new(id: u16) -> EchoHeader {
         EchoHeader {
             id: id.to_be(),
-            seq: seq.to_be(),
         }
     }
 
     pub fn get_id(&self) -> u16 {
         u16::from_be(self.id)
     }
-
-    pub fn get_seq(&self) -> u16 {
-        u16::from_be(self.seq)
-    }
 }
 
 impl<'a> SubHeader<'a> {
@@ -193,7 +188,7 @@ impl<'a> MutPacket<'a> {
     pub fn compute_checksum(&mut self) {
         self.header.crc = 0;
         let header_ptr = self.header as *mut Header as usize;
-        let total_size = mem::size_of::<Header>() + self.payload.len();
+        let total_size = Self::get_total_header_size(&self.subheader) + self.payload.len();
         let crc = Checksum::compile(unsafe { Checksum::sum(header_ptr, total_size) });
         self.header.crc = crc
     }

src/icmpd/scheme.rs

@@ -1,7 +1,7 @@
 use error::{Result, Error, PacketError};
 use netutils::{Ipv4, Ipv4Header, Checksum, n16};
 use netutils;
-use packet::{Header, Packet, MutPacket, PacketKind, SubHeader, EchoHeader};
+use packet::{Packet, MutPacket, PacketKind, SubHeader, EchoHeader};
 use std::collections::{BTreeMap, HashSet, VecDeque};
 use std::fs::File;
 use std::io::{Read, Write};
@@ -24,7 +24,6 @@ struct Handle {
     flags: usize,
     ip_addr: Ipv4Addr,
     payload_queue: VecDeque<Vec<u8>>,
-    seq: u16,
 }
 
 impl Handle {
@@ -35,7 +34,6 @@ impl Handle {
             ip_addr,
             payload_queue: VecDeque::new(),
             flags,
-            seq: 0,
         }
     }
 }
@@ -66,6 +64,7 @@ impl Icmpd {
                 break;
             }
             self.handle(&mut packet);
+            self.scheme_file.write(&packet)?;
         }
         Ok(None)
     }
@@ -108,19 +107,22 @@ impl Icmpd {
     }
 
     fn on_echo_response(&mut self, ip_packet: &Ipv4, icmp_packet: &Packet) -> Result<()> {
-        if let Some(fd_set) = self.echo_ips
-               .get_mut(&Ipv4Addr::from(ip_packet.header.src.bytes)) {
-            for fd in fd_set.iter() {
-                if let Some(handle) = self.handles.get_mut(fd) {
-                    if let &SubHeader::Echo(echo_subheader) = icmp_packet.get_subheader() {
+        if let &SubHeader::Echo(echo_subheader) = icmp_packet.get_subheader() {
+            if let Some(fd_set) = self.echo_ips
+                   .get_mut(&Ipv4Addr::from(ip_packet.header.src.bytes)) {
+                for fd in fd_set.iter() {
+                    if let Some(handle) = self.handles.get_mut(fd) {
                         if echo_subheader.get_id() == *fd as u16 {
                             handle
                                 .payload_queue
                                 .push_back(Vec::from(icmp_packet.get_payload()));
-                            post_fevent(&mut self.scheme_file,
-                                        *fd,
-                                        syscall::EVENT_READ,
-                                        icmp_packet.get_payload().len())?;
+
+                            if handle.events & syscall::EVENT_READ == syscall::EVENT_READ {
+                                post_fevent(&mut self.scheme_file,
+                                            *fd,
+                                            syscall::EVENT_READ,
+                                            icmp_packet.get_payload().len())?;
+                            }
                         }
                     }
                 }
@@ -161,10 +163,6 @@ impl SchemeMut for Icmpd {
         use std::str;
         use std::str::FromStr;
 
-        // if uid != 0 {
-        //     return Err(syscall::Error::new(syscall::EACCES));
-        // }
-
         let path = str::from_utf8(url)
             .or(Err(syscall::Error::new(syscall::EINVAL)))?;
         let mut parts = path.split("/");
@@ -216,10 +214,9 @@ impl SchemeMut for Icmpd {
                 let echo_request =
                     produce_icmp_packet(handle.ip_addr,
                                         PacketKind::EchoRequest,
-                                        &SubHeader::Echo(&EchoHeader::new(fd as u16, handle.seq)),
+                                        &SubHeader::Echo(&EchoHeader::new(fd as u16)),
                                         buf)
                             .map_err(|_| syscall::Error::new(syscall::EPROTO))?;
-                handle.seq += 1;
                 self.icmp_file
                     .write(&echo_request)
                     .map_err(|_| syscall::Error::new(syscall::EPROTO))