Add support for Packet MMAP

Author: DBLouis

Cargo.toml

@@ -36,7 +36,7 @@ once_cell = { version = "1.5.2", optional = true }
 # libc backend can be selected via adding `--cfg=rustix_use_libc` to
 # `RUSTFLAGS` or enabling the `use-libc` cargo feature.
 [target.'cfg(all(not(rustix_use_libc), not(miri), target_os = "linux", target_endian = "little", any(target_arch = "arm", all(target_arch = "aarch64", target_pointer_width = "64"), target_arch = "riscv64", all(rustix_use_experimental_asm, target_arch = "powerpc64"), all(rustix_use_experimental_asm, target_arch = "mips"), all(rustix_use_experimental_asm, target_arch = "mips32r6"), all(rustix_use_experimental_asm, target_arch = "mips64"), all(rustix_use_experimental_asm, target_arch = "mips64r6"), target_arch = "x86", all(target_arch = "x86_64", target_pointer_width = "64"))))'.dependencies]
-linux-raw-sys = { version = "0.4.12", default-features = false, features = ["general", "errno", "ioctl", "no_std", "elf"] }
+linux-raw-sys = { version = "0.6.4", default-features = false, features = ["general", "errno", "ioctl", "no_std", "elf"] }
 libc_errno = { package = "errno", version = "0.3.8", default-features = false, optional = true }
 libc = { version = "0.2.152", default-features = false, features = ["extra_traits"], optional = true }
 
@@ -53,7 +53,7 @@ libc = { version = "0.2.152", default-features = false, features = ["extra_trait
 # Some syscalls do not have libc wrappers, such as in `io_uring`. For these,
 # the libc backend uses the linux-raw-sys ABI and `libc::syscall`.
 [target.'cfg(all(any(target_os = "android", target_os = "linux"), any(rustix_use_libc, miri, not(all(target_os = "linux", target_endian = "little", any(target_arch = "arm", all(target_arch = "aarch64", target_pointer_width = "64"), target_arch = "riscv64", all(rustix_use_experimental_asm, target_arch = "powerpc64"), all(rustix_use_experimental_asm, target_arch = "mips"), all(rustix_use_experimental_asm, target_arch = "mips32r6"), all(rustix_use_experimental_asm, target_arch = "mips64"), all(rustix_use_experimental_asm, target_arch = "mips64r6"), target_arch = "x86", all(target_arch = "x86_64", target_pointer_width = "64")))))))'.dependencies]
-linux-raw-sys = { version = "0.4.12", default-features = false, features = ["general", "ioctl", "no_std"] }
+linux-raw-sys = { version = "0.6.4", default-features = false, features = ["general", "ioctl", "no_std"] }
 
 # For the libc backend on Windows, use the Winsock API in windows-sys.
 [target.'cfg(windows)'.dependencies.windows-sys]
@@ -141,7 +141,7 @@ io_uring = ["event", "fs", "net", "linux-raw-sys/io_uring"]
 mount = []
 
 # Enable `rustix::net::*`.
-net = ["linux-raw-sys/net", "linux-raw-sys/netlink", "linux-raw-sys/if_ether", "linux-raw-sys/xdp"]
+net = ["linux-raw-sys/net", "linux-raw-sys/netlink", "linux-raw-sys/if_ether", "linux-raw-sys/if_packet", "linux-raw-sys/xdp"]
 
 # Enable `rustix::thread::*`.
 thread = ["linux-raw-sys/prctl"]

examples/packet.rs

@@ -0,0 +1,75 @@
+//! Packet MMAP.
+
+#[cfg(all(feature = "mm", feature = "net", feature = "std", target_os = "linux"))]
+fn main() -> std::io::Result<()> {
+    use rustix::mm::{mmap, munmap, MapFlags, ProtFlags};
+    use rustix::net::{
+        bind_link, eth,
+        netdevice::name_to_index,
+        packet::{PacketReq, PacketReqAny, SocketAddrLink},
+        recvfrom, socket_with,
+        sockopt::{
+            get_packet_stats, set_packet_rx_ring, set_packet_tx_ring, set_packet_version,
+            PacketVersion,
+        },
+        AddressFamily, RecvFlags, SocketFlags, SocketType,
+    };
+    use std::{env::args, ptr};
+
+    let name = args().nth(0).unwrap();
+
+    let family = AddressFamily::PACKET;
+    let type_ = SocketType::RAW;
+    let flags = SocketFlags::empty();
+    let fd = socket_with(family, type_, flags, None)?;
+
+    let index = name_to_index(&fd, &name)?;
+
+    set_packet_version(&fd, PacketVersion::V2)?;
+
+    let req = PacketReq {
+        block_size: 4096,
+        block_nr: 4,
+        frame_size: 2048,
+        frame_nr: 8,
+    };
+    let size = req.block_size as usize * req.block_nr as usize;
+
+    let req = PacketReqAny::V2(req);
+    set_packet_rx_ring(&fd, &req)?;
+    set_packet_tx_ring(&fd, &req)?;
+
+    let rx = unsafe {
+        mmap(
+            ptr::null_mut(),
+            size * 2,
+            ProtFlags::READ | ProtFlags::WRITE,
+            MapFlags::SHARED,
+            &fd,
+            0,
+        )
+    }?;
+    let _tx = rx.wrapping_add(size);
+
+    let addr = SocketAddrLink::new(eth::ALL, index);
+    bind_link(&fd, &addr)?;
+
+    while let Ok(_) = recvfrom(&fd, &mut [], RecvFlags::empty()) {}
+
+    let stats = get_packet_stats(&fd, PacketVersion::V2)?;
+    println!("{:?}", stats);
+
+    unsafe { munmap(rx, size * 2) }?;
+
+    Ok(())
+}
+
+#[cfg(any(
+    not(feature = "mm"),
+    not(feature = "net"),
+    not(feature = "std"),
+    not(target_os = "linux")
+))]
+fn main() -> Result<(), &'static str> {
+    Err("This example requires --features=mm,net,std and is only supported on Linux.")
+}

src/backend/linux_raw/c.rs

@@ -55,13 +55,14 @@ pub(crate) use linux_raw_sys::{
     cmsg_macros::*,
     general::{O_CLOEXEC as SOCK_CLOEXEC, O_NONBLOCK as SOCK_NONBLOCK},
     if_ether::*,
+    if_packet::*,
     net::{
         linger, msghdr, sockaddr, sockaddr_in, sockaddr_in6, sockaddr_un, socklen_t, AF_DECnet,
         __kernel_sa_family_t as sa_family_t, __kernel_sockaddr_storage as sockaddr_storage,
-        cmsghdr, in6_addr, in_addr, ip_mreq, ip_mreq_source, ip_mreqn, ipv6_mreq, AF_APPLETALK,
-        AF_ASH, AF_ATMPVC, AF_ATMSVC, AF_AX25, AF_BLUETOOTH, AF_BRIDGE, AF_CAN, AF_ECONET,
-        AF_IEEE802154, AF_INET, AF_INET6, AF_IPX, AF_IRDA, AF_ISDN, AF_IUCV, AF_KEY, AF_LLC,
-        AF_NETBEUI, AF_NETLINK, AF_NETROM, AF_PACKET, AF_PHONET, AF_PPPOX, AF_RDS, AF_ROSE,
+        cmsghdr, ifreq, in6_addr, in_addr, ip_mreq, ip_mreq_source, ip_mreqn, ipv6_mreq,
+        AF_APPLETALK, AF_ASH, AF_ATMPVC, AF_ATMSVC, AF_AX25, AF_BLUETOOTH, AF_BRIDGE, AF_CAN,
+        AF_ECONET, AF_IEEE802154, AF_INET, AF_INET6, AF_IPX, AF_IRDA, AF_ISDN, AF_IUCV, AF_KEY,
+        AF_LLC, AF_NETBEUI, AF_NETLINK, AF_NETROM, AF_PACKET, AF_PHONET, AF_PPPOX, AF_RDS, AF_ROSE,
         AF_RXRPC, AF_SECURITY, AF_SNA, AF_TIPC, AF_UNIX, AF_UNSPEC, AF_WANPIPE, AF_X25, AF_XDP,
         IP6T_SO_ORIGINAL_DST, IPPROTO_FRAGMENT, IPPROTO_ICMPV6, IPPROTO_MH, IPPROTO_ROUTING,
         IPV6_ADD_MEMBERSHIP, IPV6_DROP_MEMBERSHIP, IPV6_FREEBIND, IPV6_MULTICAST_HOPS,
@@ -71,12 +72,12 @@ pub(crate) use linux_raw_sys::{
         MSG_CMSG_CLOEXEC, MSG_CONFIRM, MSG_DONTROUTE, MSG_DONTWAIT, MSG_EOR, MSG_ERRQUEUE,
         MSG_MORE, MSG_NOSIGNAL, MSG_OOB, MSG_PEEK, MSG_TRUNC, MSG_WAITALL, SCM_CREDENTIALS,
         SCM_RIGHTS, SHUT_RD, SHUT_RDWR, SHUT_WR, SOCK_DGRAM, SOCK_RAW, SOCK_RDM, SOCK_SEQPACKET,
-        SOCK_STREAM, SOL_SOCKET, SOL_XDP, SO_ACCEPTCONN, SO_BROADCAST, SO_COOKIE, SO_DOMAIN,
-        SO_ERROR, SO_INCOMING_CPU, SO_KEEPALIVE, SO_LINGER, SO_OOBINLINE, SO_ORIGINAL_DST,
-        SO_PASSCRED, SO_PROTOCOL, SO_RCVBUF, SO_RCVTIMEO_NEW, SO_RCVTIMEO_NEW as SO_RCVTIMEO,
-        SO_RCVTIMEO_OLD, SO_REUSEADDR, SO_REUSEPORT, SO_SNDBUF, SO_SNDTIMEO_NEW,
-        SO_SNDTIMEO_NEW as SO_SNDTIMEO, SO_SNDTIMEO_OLD, SO_TYPE, TCP_CONGESTION, TCP_CORK,
-        TCP_KEEPCNT, TCP_KEEPIDLE, TCP_KEEPINTVL, TCP_NODELAY, TCP_QUICKACK,
+        SOCK_STREAM, SOL_PACKET, SOL_SOCKET, SOL_XDP, SO_ACCEPTCONN, SO_BROADCAST, SO_COOKIE,
+        SO_DOMAIN, SO_ERROR, SO_INCOMING_CPU, SO_KEEPALIVE, SO_LINGER, SO_OOBINLINE,
+        SO_ORIGINAL_DST, SO_PASSCRED, SO_PROTOCOL, SO_RCVBUF, SO_RCVTIMEO_NEW,
+        SO_RCVTIMEO_NEW as SO_RCVTIMEO, SO_RCVTIMEO_OLD, SO_REUSEADDR, SO_REUSEPORT, SO_SNDBUF,
+        SO_SNDTIMEO_NEW, SO_SNDTIMEO_NEW as SO_SNDTIMEO, SO_SNDTIMEO_OLD, SO_TYPE, TCP_CONGESTION,
+        TCP_CORK, TCP_KEEPCNT, TCP_KEEPIDLE, TCP_KEEPINTVL, TCP_NODELAY, TCP_QUICKACK,
         TCP_THIN_LINEAR_TIMEOUTS, TCP_USER_TIMEOUT,
     },
     netlink::*,

src/backend/linux_raw/net/sockopt.rs

@@ -11,7 +11,9 @@ use crate::fd::BorrowedFd;
 #[cfg(feature = "alloc")]
 use crate::ffi::CStr;
 use crate::io;
-use crate::net::sockopt::Timeout;
+#[cfg(target_os = "linux")]
+use crate::net::packet::{PacketReqAny, PacketStats, PacketStats3, PacketStatsAny};
+use crate::net::sockopt::{PacketVersion, Timeout};
 #[cfg(target_os = "linux")]
 use crate::net::xdp::{XdpMmapOffsets, XdpOptionsFlags, XdpRingOffset, XdpStatistics, XdpUmemReg};
 use crate::net::{
@@ -967,6 +969,62 @@ pub(crate) fn get_xdp_options(fd: BorrowedFd<'_>) -> io::Result<XdpOptionsFlags>
     getsockopt(fd, c::SOL_XDP, c::XDP_OPTIONS)
 }
 
+#[cfg(target_os = "linux")]
+#[inline]
+pub(crate) fn set_packet_rx_ring(fd: BorrowedFd<'_>, value: &PacketReqAny) -> io::Result<()> {
+    match value {
+        PacketReqAny::V1(value) | PacketReqAny::V2(value) => {
+            setsockopt(fd, c::SOL_PACKET, c::PACKET_RX_RING, value)
+        }
+        PacketReqAny::V3(value) => setsockopt(fd, c::SOL_PACKET, c::PACKET_RX_RING, value),
+    }
+}
+
+#[cfg(target_os = "linux")]
+#[inline]
+pub(crate) fn set_packet_tx_ring(fd: BorrowedFd<'_>, value: &PacketReqAny) -> io::Result<()> {
+    match value {
+        PacketReqAny::V1(value) | PacketReqAny::V2(value) => {
+            setsockopt(fd, c::SOL_PACKET, c::PACKET_TX_RING, value)
+        }
+        PacketReqAny::V3(value) => setsockopt(fd, c::SOL_PACKET, c::PACKET_TX_RING, value),
+    }
+}
+
+#[cfg(target_os = "linux")]
+#[inline]
+pub(crate) fn set_packet_version(fd: BorrowedFd<'_>, value: PacketVersion) -> io::Result<()> {
+    setsockopt(fd, c::SOL_PACKET, c::PACKET_VERSION, value)
+}
+
+#[cfg(target_os = "linux")]
+#[inline]
+pub(crate) fn get_packet_version(fd: BorrowedFd<'_>) -> io::Result<PacketVersion> {
+    getsockopt(fd, c::SOL_PACKET, c::PACKET_VERSION)
+}
+
+#[cfg(target_os = "linux")]
+#[inline]
+pub(crate) fn get_packet_stats(
+    fd: BorrowedFd<'_>,
+    version: PacketVersion,
+) -> io::Result<PacketStatsAny> {
+    match version {
+        PacketVersion::V1 => {
+            let stats: PacketStats = getsockopt(fd, c::SOL_PACKET, c::PACKET_STATISTICS)?;
+            Ok(PacketStatsAny::V1(stats))
+        }
+        PacketVersion::V2 => {
+            let stats: PacketStats = getsockopt(fd, c::SOL_PACKET, c::PACKET_STATISTICS)?;
+            Ok(PacketStatsAny::V2(stats))
+        }
+        PacketVersion::V3 => {
+            let stats: PacketStats3 = getsockopt(fd, c::SOL_PACKET, c::PACKET_STATISTICS)?;
+            Ok(PacketStatsAny::V3(stats))
+        }
+    }
+}
+
 #[inline]
 fn to_ip_mreq(multiaddr: &Ipv4Addr, interface: &Ipv4Addr) -> c::ip_mreq {
     c::ip_mreq {

src/backend/linux_raw/net/syscalls.rs

@@ -23,6 +23,8 @@ use crate::backend::conv::{
 use crate::fd::{BorrowedFd, OwnedFd};
 use crate::io::{self, IoSlice, IoSliceMut};
 #[cfg(target_os = "linux")]
+use crate::net::packet::SocketAddrLink;
+#[cfg(target_os = "linux")]
 use crate::net::xdp::SocketAddrXdp;
 use crate::net::{
     AddressFamily, Protocol, RecvAncillaryBuffer, RecvMsgReturn, SendAncillaryBuffer, Shutdown,
@@ -439,6 +441,18 @@ pub(crate) fn sendmsg_xdp(
     })
 }
 
+#[cfg(target_os = "linux")]
+#[inline]
+pub(crate) fn sendmsg_link(
+    _sockfd: BorrowedFd<'_>,
+    _addr: &SocketAddrLink,
+    _iov: &[IoSlice<'_>],
+    _control: &mut SendAncillaryBuffer<'_, '_, '_>,
+    _msg_flags: SendFlags,
+) -> io::Result<usize> {
+    todo!()
+}
+
 #[inline]
 pub(crate) fn shutdown(fd: BorrowedFd<'_>, how: Shutdown) -> io::Result<()> {
     #[cfg(not(target_arch = "x86"))]
@@ -660,6 +674,17 @@ pub(crate) fn sendto_xdp(
     }
 }
 
+#[cfg(target_os = "linux")]
+#[inline]
+pub(crate) fn sendto_link(
+    _fd: BorrowedFd<'_>,
+    _buf: &[u8],
+    _flags: SendFlags,
+    _addr: &SocketAddrLink,
+) -> io::Result<usize> {
+    todo!()
+}
+
 #[inline]
 pub(crate) unsafe fn recv(
     fd: BorrowedFd<'_>,
@@ -931,6 +956,12 @@ pub(crate) fn bind_xdp(fd: BorrowedFd<'_>, addr: &SocketAddrXdp) -> io::Result<(
     }
 }
 
+#[cfg(target_os = "linux")]
+#[inline]
+pub(crate) fn bind_link(_fd: BorrowedFd<'_>, _addr: &SocketAddrLink) -> io::Result<()> {
+    todo!()
+}
+
 #[inline]
 pub(crate) fn connect_v4(fd: BorrowedFd<'_>, addr: &SocketAddrV4) -> io::Result<()> {
     #[cfg(not(target_arch = "x86"))]

src/backend/linux_raw/net/write_sockaddr.rs

@@ -4,6 +4,8 @@
 
 use crate::backend::c;
 #[cfg(target_os = "linux")]
+use crate::net::packet::SocketAddrLink;
+#[cfg(target_os = "linux")]
 use crate::net::xdp::SocketAddrXdp;
 use crate::net::{SocketAddrAny, SocketAddrStorage, SocketAddrUnix, SocketAddrV4, SocketAddrV6};
 use core::mem::size_of;
@@ -18,6 +20,8 @@ pub(crate) unsafe fn write_sockaddr(
         SocketAddrAny::Unix(unix) => write_sockaddr_unix(unix, storage),
         #[cfg(target_os = "linux")]
         SocketAddrAny::Xdp(xdp) => write_sockaddr_xdp(xdp, storage),
+        #[cfg(target_os = "linux")]
+        SocketAddrAny::Link(link) => write_sockaddr_link(link, storage),
     }
 }
 
@@ -80,3 +84,9 @@ unsafe fn write_sockaddr_xdp(xdp: &SocketAddrXdp, storage: *mut SocketAddrStorag
     core::ptr::write(storage.cast(), encoded);
     size_of::<c::sockaddr_xdp>()
 }
+
+#[cfg(target_os = "linux")]
+unsafe fn write_sockaddr_link(link: &SocketAddrLink, storage: *mut SocketAddrStorage) -> usize {
+    core::ptr::write(storage.cast(), link);
+    size_of::<c::sockaddr_ll>()
+}

src/net/mod.rs

@@ -18,6 +18,8 @@ mod wsa;
 
 #[cfg(linux_kernel)]
 pub mod netdevice;
+#[cfg(linux_kernel)]
+pub mod packet;
 pub mod sockopt;
 
 pub use crate::maybe_polyfill::net::{