1 files changed, 39 insertions, 155 deletions
diff --git a/rust/daemon/src/wifi/frame.rs b/rust/daemon/src/wifi/frame.rs
index 4b8f462e..1ec89044 100644
--- a/rust/daemon/src/wifi/frame.rs
+++ b/rust/daemon/src/wifi/frame.rs
@@ -12,175 +12,59 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use super::ieee80211::Ieee80211;
-use super::packets::mac80211_hwsim::HwsimAttrChild::*;
-use super::packets::mac80211_hwsim::{HwsimAttr, HwsimMsg, HwsimMsgHdr, TxRate, TxRateFlag};
-use super::packets::netlink::{NlAttrHdr, NlMsgHdr};
+use super::ieee80211::{Ieee80211, MacAddress};
+use super::packets::mac80211_hwsim::{
+    HwsimAttr, HwsimCmd, HwsimMsg, HwsimMsgHdr, TxRate, TxRateFlag,
+};
+use crate::wifi::hwsim_attr_set::HwsimAttrSet;
 use anyhow::{anyhow, Context};
 use log::{info, warn};
-use std::mem;
 
-// Decode the hwsim Frame.
-//
-// HWSIM_CMD_FRAME is used to send/receive a broadcasted frame from/to
-// kernel/user space, uses these attributes:
-//
-//   HWSIM_ATTR_ADDR_TRANSMITTER,
-//   HWSIM_ATTR_ADDR_RECEIVER,
-//   HWSIM_ATTR_FRAME,
-//   HWSIM_ATTR_FLAGS,
-//   HWSIM_ATTR_RX_RATE,
-//   HWSIM_ATTR_SIGNAL,
-//   HWSIM_ATTR_COOKIE,
-//   HWSIM_ATTR_FREQ (optional)
-//   HWSIM_ATTR_TX_INFO (new use)
-//   HWSIM_ATTR_TX_INFO_FLAGS (new use)
-
-const NLA_ALIGNTO: usize = 4;
-
-fn nla_align(len: usize) -> usize {
-    len.wrapping_add(NLA_ALIGNTO - 1) & !(NLA_ALIGNTO - 1)
-}
-
-#[derive(Default)]
-struct FrameBuilder {
-    transmitter: Option<[u8; 6]>,
-    receiver: Option<[u8; 6]>,
-    data: Option<Vec<u8>>,
-    flags: Option<u32>,
-    rx_rate_idx: Option<u32>,
-    signal: Option<u32>,
-    cookie: Option<u64>,
-    freq: Option<u32>,
-    tx_rates: Option<Vec<TxRate>>,
-    tx_rate_flags: Option<Vec<TxRateFlag>>,
-}
+/// Parser for the hwsim Frame command (HWSIM_CMD_FRAME).
+///
+/// The Frame command is sent by the kernel's mac80211_hwsim subsystem
+/// and contains the IEEE 802.11 frame along with hwsim attributes.
+///
+/// This module parses the required and optional hwsim attributes and
+/// returns errors if any required attributes are missing.
 
+// The Frame struct contains parsed attributes along with the raw and
+// parsed 802.11 frame in `data` and `ieee80211.`
 #[derive(Debug)]
 pub struct Frame {
-    transmitter: Option<[u8; 6]>,
-    receiver: Option<[u8; 6]>,
-    pub data: Vec<u8>,
-    pub ieee80211_hdr: Option<Ieee80211>,
-    pub flags: Option<u32>,
-    rx_rate_idx: Option<u32>,
+    pub transmitter: MacAddress,
+    pub flags: u32,
+    pub tx_info: Vec<TxRate>,
+    pub cookie: u64,
     pub signal: Option<u32>,
-    cookie: Option<u64>,
     pub freq: Option<u32>,
-    tx_rates: Option<Vec<TxRate>>,
-    tx_rate_flags: Option<Vec<TxRateFlag>>,
-}
-
-fn anymsg(attr: &str) -> anyhow::Error {
-    anyhow!("hwsim Frame missing {} attribute", attr)
-}
-
-impl FrameBuilder {
-    fn transmitter(&mut self, transmitter: &[u8; 6]) -> &mut Self {
-        self.transmitter = Some(*transmitter);
-        self
-    }
-
-    fn receiver(&mut self, receiver: &[u8; 6]) -> &mut Self {
-        self.receiver = Some(*receiver);
-        self
-    }
-
-    fn frame(&mut self, data: &[u8]) -> &mut Self {
-        self.data = Some(data.to_vec());
-        self
-    }
-
-    fn flags(&mut self, flags: u32) -> &mut Self {
-        self.flags = Some(flags);
-        self
-    }
-
-    fn rx_rate(&mut self, rx_rate_idx: u32) -> &mut Self {
-        self.rx_rate_idx = Some(rx_rate_idx);
-        self
-    }
-
-    fn signal(&mut self, signal: u32) -> &mut Self {
-        self.signal = Some(signal);
-        self
-    }
-
-    fn cookie(&mut self, cookie: u64) -> &mut Self {
-        self.cookie = Some(cookie);
-        self
-    }
-
-    fn freq(&mut self, freq: u32) -> &mut Self {
-        self.freq = Some(freq);
-        self
-    }
-
-    fn tx_rates(&mut self, tx_rates: &[TxRate]) -> &mut Self {
-        self.tx_rates = Some(tx_rates.to_vec());
-        self
-    }
-
-    fn tx_rate_flags(&mut self, tx_rate_flags: &[TxRateFlag]) -> &mut Self {
-        self.tx_rate_flags = Some(tx_rate_flags.to_vec());
-        self
-    }
-
-    fn build(mut self) -> anyhow::Result<Frame> {
-        let data = self.data.ok_or(anymsg("frame"))?;
-        let ieee80211_hdr = Ieee80211::parse(&data).ok();
-        Ok(Frame {
-            transmitter: self.transmitter,
-            receiver: self.receiver,
-            cookie: self.cookie,
-            flags: self.flags,
-            rx_rate_idx: self.rx_rate_idx,
-            signal: self.signal,
-            data,
-            ieee80211_hdr,
-            freq: self.freq,
-            tx_rates: self.tx_rates,
-            tx_rate_flags: self.tx_rate_flags,
-        })
-    }
+    pub data: Vec<u8>,
+    pub ieee80211: Ieee80211,
 }
 
 impl Frame {
-    fn builder() -> FrameBuilder {
-        FrameBuilder::default()
-    }
-
     // Builds and validates the Frame from the attributes in the
     // packet. Called when a hwsim packet with HwsimCmd::Frame is
     // found.
-    pub fn new(attributes: &[u8]) -> anyhow::Result<Frame> {
-        let mut index: usize = 0;
-        let mut builder = Frame::builder();
-        while (index < attributes.len()) {
-            // Parse a generic netlink attribute to get the size
-            let nla = NlAttrHdr::parse(&attributes[index..index + 4]).unwrap();
-            let nla_len = nla.nla_len as usize;
-            let hwsim_attr = HwsimAttr::parse(&attributes[index..index + nla_len])?;
-            match hwsim_attr.specialize() {
-                HwsimAttrAddrTransmitter(child) => builder.transmitter(child.get_address()),
-                HwsimAttrAddrReceiver(child) => builder.receiver(child.get_address()),
-                HwsimAttrFrame(child) => builder.frame(child.get_data()),
-                HwsimAttrFlags(child) => builder.flags(child.get_flags()),
-                HwsimAttrRxRate(child) => builder.rx_rate(child.get_rx_rate_idx()),
-                HwsimAttrSignal(child) => builder.signal(child.get_signal()),
-                HwsimAttrCookie(child) => builder.cookie(child.get_cookie()),
-                HwsimAttrFreq(child) => builder.freq(child.get_freq()),
-                HwsimAttrTxInfo(child) => builder.tx_rates(child.get_tx_rates()),
-                HwsimAttrTxInfoFlags(child) => builder.tx_rate_flags(child.get_tx_rate_flags()),
-                _ => {
-                    return Err(anyhow!(
-                        "Invalid attribute in frame: {:?}",
-                        hwsim_attr.get_nla_type() as u32
-                    ))
-                }
-            };
-            index += nla_align(nla_len);
+    pub fn parse(msg: &HwsimMsg) -> anyhow::Result<Frame> {
+        // Only expected to be called with HwsimCmd::Frame
+        if (msg.hwsim_hdr.hwsim_cmd != HwsimCmd::Frame) {
+            panic!("Invalid hwsim_cmd");
         }
-        builder.build()
+        let attrs = HwsimAttrSet::parse(&msg.attributes).context("HwsimAttrSet")?;
+        let frame = attrs.frame.clone().context("Frame")?;
+        let ieee80211 = Ieee80211::parse(&frame).context("Ieee80211")?;
+        // Required attributes are unwrapped and return an error if
+        // they are not present.
+        Ok(Frame {
+            transmitter: attrs.transmitter.context("transmitter")?,
+            flags: attrs.flags.context("flags")?,
+            tx_info: attrs.tx_info.clone().context("tx_info")?,
+            cookie: attrs.cookie.context("cookie")?,
+            signal: attrs.signal,
+            freq: attrs.freq,
+            data: frame,
+            ieee80211,
+        })
     }
 }