1 files changed, 90 insertions, 0 deletions
diff --git a/crates/windivert/src/packet.rs b/crates/windivert/src/packet.rs
new file mode 100644
index 0000000..ea81fe9
--- /dev/null
+++ b/crates/windivert/src/packet.rs
@@ -0,0 +1,90 @@
+use windivert_sys::{ChecksumFlags, WinDivertHelperCalcChecksums};
+
+use crate::{address::WinDivertAddress, layer, prelude::WinDivertError};
+
+use std::{
+    borrow::{BorrowMut, Cow},
+    ffi::c_void,
+    fmt::Debug,
+};
+
+/// Raw captured packet
+#[derive(Debug, Clone)]
+pub struct WinDivertPacket<'a, L: layer::WinDivertLayerTrait> {
+    /// Address data
+    pub address: WinDivertAddress<L>,
+    /// Raw captured data
+    pub data: Cow<'a, [u8]>,
+}
+
+impl<'a> WinDivertPacket<'a, layer::NetworkLayer> {
+    /// Create a new network packet from a raw buffer
+    /// # Safety
+    /// `address` is zeroed, user must fill it with correct data before sending.
+    pub unsafe fn new(data: Vec<u8>) -> Self {
+        Self {
+            address: WinDivertAddress::<layer::NetworkLayer>::new(),
+            data: Cow::from(data),
+        }
+    }
+
+    /// Recalculate the checksums of the packet
+    /// This is a noop if the packet is not owned.
+    pub fn recalculate_checksums(&mut self, flags: ChecksumFlags) -> Result<(), WinDivertError> {
+        if let Cow::Owned(ref mut data) = self.data.borrow_mut() {
+            let res = unsafe {
+                WinDivertHelperCalcChecksums(
+                    data.as_mut_ptr() as *mut c_void,
+                    data.len() as u32,
+                    self.address.as_mut(),
+                    flags,
+                )
+            };
+            if !res.as_bool() {
+                return Err(WinDivertError::from(windows::core::Error::from_win32()));
+            }
+        }
+        Ok(())
+    }
+}
+
+impl<'a> WinDivertPacket<'a, layer::ForwardLayer> {
+    /// Create a new network forward packet from a raw buffer
+    /// # Safety
+    /// `address` is zeroed, user must fill it with correct data before sending.
+    pub unsafe fn new(data: Vec<u8>) -> Self {
+        Self {
+            address: WinDivertAddress::<layer::ForwardLayer>::new(),
+            data: Cow::from(data),
+        }
+    }
+
+    /// Recalculate the checksums of the packet
+    /// This is a noop if the packet is not owned.
+    pub fn recalculate_checksums(&mut self, flags: ChecksumFlags) -> Result<(), WinDivertError> {
+        if let Cow::Owned(ref mut data) = self.data.borrow_mut() {
+            let res = unsafe {
+                WinDivertHelperCalcChecksums(
+                    data.as_mut_ptr() as *mut c_void,
+                    data.len() as u32,
+                    self.address.as_mut(),
+                    flags,
+                )
+            };
+            if !res.as_bool() {
+                return Err(WinDivertError::from(windows::core::Error::from_win32()));
+            }
+        }
+        Ok(())
+    }
+}
+
+impl<'a, L: layer::WinDivertLayerTrait> WinDivertPacket<'a, L> {
+    /// Create an owned packet from a borrowed packet
+    pub fn into_owned(self) -> WinDivertPacket<'static, L> {
+        WinDivertPacket {
+            address: self.address,
+            data: self.data.into_owned().into(),
+        }
+    }
+}