create pppoe discovery socket

5 files changed, 72 insertions, 2 deletions

diff --git a/Cargo.lock b/Cargo.lock
index d6fb31e..31623ae 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -262,12 +262,14 @@ dependencies = [
 name = "rsdsl_pppoe3"
 version = "0.1.0"
 dependencies = [
+ "libc",
  "ppproperly",
  "rand",
  "rsdsl_ip_config",
  "serde",
  "serde_json",
  "socket2",
+ "thiserror",
  "tokio",
 ]
 
diff --git a/Cargo.toml b/Cargo.toml
index 8db6101..162ec85 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,10 +6,12 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+libc = "0.2.149"
 ppproperly = { git = "https://github.com/rsdsl/ppproperly.git", version = "0.1.0" }
 rand = "0.8.5"
 rsdsl_ip_config = { git = "https://github.com/rsdsl/ip_config.git", version = "0.2.3" }
 serde = "1.0"
 serde_json = "1.0"
 socket2 = "0.5.5"
+thiserror = "1.0"
 tokio = { version = "1.0", features = ["rt-multi-thread", "macros", "sync", "time"] }
diff --git a/src/error.rs b/src/error.rs
new file mode 100644
index 0000000..8da1cfc
--- /dev/null
+++ b/src/error.rs
@@ -0,0 +1,13 @@
+use std::{ffi, io};
+
+use thiserror::Error;
+
+#[derive(Debug, Error)]
+pub enum Error {
+    #[error("io: {0}")]
+    Io(#[from] io::Error),
+    #[error("interface name contains nul byte: {0}")]
+    Nul(#[from] ffi::NulError),
+}
+
+pub type Result<T> = std::result::Result<T, Error>;
diff --git a/src/lib.rs b/src/lib.rs
index 0e666a4..9692924 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,3 +1,6 @@
+mod error;
+pub use error::*;
+
 mod proto;
 pub use proto::*;
 
diff --git a/src/supervisor.rs b/src/supervisor.rs
index 6905a92..a5d349d 100644
--- a/src/supervisor.rs
+++ b/src/supervisor.rs
@@ -1,3 +1,4 @@
+use crate::Result;
 use crate::{
     chap::ChapClient,
     pap::PapClient,
@@ -5,10 +6,18 @@ use crate::{
     proto::{NegotiationProtocol, ProtocolConfig},
 };
 
+use std::ffi::CString;
 use std::net::Ipv4Addr;
+use std::{io, mem};
 
 use ppproperly::{IpCompressionProtocol, IpcpOpt, Ipv6cpOpt, LcpOpt, QualityProtocol};
-// use socket2::Socket;
+use socket2::{SockAddr, Socket};
+
+macro_rules! os_err {
+    () => {
+        return Err(io::Error::last_os_error().into());
+    };
+}
 
 /// A client control instance for full dual stack PPPoE sessions.
 #[derive(Debug)]
@@ -122,6 +131,47 @@ impl Client {
 
     /// Runs the connection. Blocks the caller forever unless a panic occurs.
     pub fn run(&self) {
-        // let sock_disc = self.new_discovery_socket();
+        let sock_disc = self.new_discovery_socket();
+    }
+
+    fn new_discovery_socket(&self) -> Result<Socket> {
+        use libc::{
+            sockaddr_ll, sockaddr_storage, socklen_t, AF_PACKET, ETH_P_PPP_DISC, PF_PACKET,
+            SOCK_RAW,
+        };
+
+        let sock = Socket::new(
+            PF_PACKET.into(),
+            SOCK_RAW.into(),
+            Some(ETH_P_PPP_DISC.into()),
+        )?;
+
+        sock.set_broadcast(true)?;
+
+        let c_link = CString::new(&*self.link)?;
+
+        let ifi = unsafe { libc::if_nametoindex(c_link.as_ptr()) };
+        if ifi == 0 {
+            os_err!();
+        }
+
+        let sa = sockaddr_ll {
+            sll_family: AF_PACKET as u16,
+            sll_protocol: (ETH_P_PPP_DISC as u16).to_be(),
+            sll_ifindex: ifi as i32,
+            sll_hatype: 0,
+            sll_pkttype: 0,
+            sll_halen: 0,
+            sll_addr: [0; 8],
+        };
+
+        sock.bind(&unsafe {
+            SockAddr::new(
+                *mem::transmute::<*const sockaddr_ll, *const sockaddr_storage>(&sa),
+                mem::size_of_val(&sa) as socklen_t,
+            )
+        })?;
+
+        Ok(sock)
     }
 }