Add support for XChannel field on RadioTap

include/tins/radiotap.h

@@ -84,7 +84,7 @@ public:
      */
     enum PresentFlags {
         TSFT                = 1 << 0,
-        TSTF                = 1 << 0, // Deprecated (typo in the name...)
+        TSTF                = 1 << 0, ///< Deprecated (typo), use TSFT
         FLAGS               = 1 << 1,
         RATE                = 1 << 2,
         CHANNEL             = 1 << 3,
@@ -101,6 +101,7 @@ public:
         RX_FLAGS            = 1 << 14,
         TX_FLAGS            = 1 << 15,
         DATA_RETRIES        = 1 << 17,
+        XCHANNEL            = 1 << 18,
         CHANNEL_PLUS        = 1 << 18,
         MCS                 = 1 << 19
     };
@@ -128,6 +129,17 @@ public:
         uint8_t flags;
         uint8_t mcs;
     } TINS_END_PACK;
+
+    /**
+     * \brief The type used to represent the XChannel field
+     */
+    TINS_BEGIN_PACK
+    struct xchannel_type {
+        uint32_t flags;
+        uint16_t frequency;
+        uint8_t channel;
+        uint8_t max_power;
+    } TINS_END_PACK;
     
     /**
      * The type used to store RadioTap options
@@ -250,6 +262,12 @@ public:
      */
     void tx_flags(uint16_t new_tx_flag);
 
+    /**
+     * \brief Setter for the xchannel field.
+     * \param new_xchannel The xchannel field
+     */
+    void xchannel(xchannel_type new_xchannel);
+
     /**
      * \brief Setter for the data retries field.
      * \param new_rx_flag The data retries.
@@ -343,10 +361,10 @@ public:
     uint8_t db_signal() const;
     
     /**
-     * \brief Getter for the channel+ field.
-     * \return The channel+ field.
+     * \brief Getter for the XChannel field.
+     * \return The XChannel field.
      */
-    uint32_t channel_plus() const;
+    xchannel_type xchannel() const;
     
     /**
      * \brief Getter for the data retries field

src/radiotap.cpp

@@ -180,6 +180,14 @@ void RadioTap::tx_flags(uint16_t new_tx_flags) {
     add_integral_option(*this, TX_FLAGS, new_tx_flags);
 }
 
+void RadioTap::xchannel(xchannel_type new_xchannel) {
+    uint8_t buffer[sizeof(new_xchannel)];
+    new_xchannel.flags = Endian::host_to_le(new_xchannel.flags);
+    new_xchannel.frequency = Endian::host_to_le(new_xchannel.frequency);
+    memcpy(buffer, &new_xchannel, sizeof(new_xchannel));
+    add_option(RadioTap::option(XCHANNEL, sizeof(buffer), buffer));
+}
+
 void RadioTap::mcs(const mcs_type& new_mcs) {
     uint8_t buffer[sizeof(new_mcs)];
     memcpy(buffer, &new_mcs, sizeof(new_mcs));
@@ -279,7 +287,7 @@ uint8_t RadioTap::antenna() const {
 RadioTap::mcs_type RadioTap::mcs() const {
     const option opt = do_find_option(MCS);
     mcs_type output;
-    memcpy(&output, opt.data_ptr(), sizeof(mcs_type));
+    memcpy(&output, opt.data_ptr(), sizeof(output));
     return output;
 }
 
@@ -287,13 +295,13 @@ uint8_t RadioTap::db_signal() const {
     return do_find_option(DB_SIGNAL).to<uint8_t>();
 }
 
-uint32_t RadioTap::channel_plus() const {
-    /*if (!header_.flags.channel_plus) {
-        throw field_not_present();
-    }
-    return Endian::le_to_host<uint32_t>(channel_type_);*/
-    // TODO: wat
-    return 0xdadedade;
+RadioTap::xchannel_type RadioTap::xchannel() const {
+    const option opt = do_find_option(XCHANNEL);
+    xchannel_type output;
+    memcpy(&output, opt.data_ptr(), sizeof(output));
+    output.flags = Endian::le_to_host(output.flags);
+    output.frequency = Endian::le_to_host(output.frequency);
+    return output;
 }
 
 uint16_t RadioTap::rx_flags() const {
@@ -355,19 +363,6 @@ void RadioTap::write_serialization(uint8_t* buffer, uint32_t total_sz) {
     header_.it_len = Endian::host_to_le<uint16_t>(header_size());
     stream.write(header_);
     stream.write(options_payload_.begin(), options_payload_.end());
-    /*if (header_.flags.channel_plus) {
-        const uint32_t padding = ((stream.pointer() - buffer_start) % 4);
-        if (padding != 0) {
-            stream.fill(4 - padding, 0);
-        }
-        uint32_t dummy = channel_type_;
-        // nasty Big Endian fix
-        dummy = Endian::le_to_host<uint32_t>(Endian::host_to_le<uint16_t>(dummy));
-        stream.write(dummy);
-        stream.write(channel_freq_);
-        stream.write(channel_);
-        stream.write(max_power_);
-    }*/
 
     // If we have a trailer size, then we have the FCS flag on
     if (trailer_size() > 0 && inner_pdu()) {

tests/src/radiotap_test.cpp

@@ -346,7 +346,7 @@ TEST_F(RadioTapTest, ConstructorFromBuffer) {
     EXPECT_TRUE((radio.present() & RadioTap::RATE) != 0);
     EXPECT_TRUE((radio.present() & RadioTap::DBM_SIGNAL) != 0);
     EXPECT_TRUE((radio.present() & RadioTap::ANTENNA) != 0);
-    EXPECT_TRUE((radio.present() & RadioTap::CHANNEL_PLUS) != 0);
+    EXPECT_TRUE((radio.present() & RadioTap::XCHANNEL) != 0);
     
     EXPECT_TRUE((radio.flags() & RadioTap::FCS) != 0);
     EXPECT_THROW(radio.channel_type(), field_not_present);
@@ -507,6 +507,22 @@ TEST_F(RadioTapTest, TSFT) {
     EXPECT_EQ(radio.tsft(), 0x7afb9a8dU);
 }
 
+TEST_F(RadioTapTest, XChannel) {
+    RadioTap radio;
+    RadioTap::xchannel_type xchannel;
+    xchannel.flags = 0xabcd1234;
+    xchannel.frequency = 0xda21;
+    xchannel.max_power = 0x19;
+    xchannel.channel = 0x99;
+    radio.xchannel(xchannel);
+
+    RadioTap::xchannel_type found_xchannel = radio.xchannel();
+    EXPECT_EQ(xchannel.flags, found_xchannel.flags);
+    EXPECT_EQ(xchannel.frequency, found_xchannel.frequency);
+    EXPECT_EQ(xchannel.max_power, found_xchannel.max_power);
+    EXPECT_EQ(xchannel.channel, found_xchannel.channel);
+}
+
 TEST_F(RadioTapTest, SerializationWorksFine) {
     const uint8_t expected[] = {
         0, 0, 26, 0, 43, 72, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 0, 108,
@@ -555,7 +571,7 @@ TEST_F(RadioTapTest, RadioTapParsing) {
     EXPECT_EQ(2, parser.current_option().to<uint8_t>());
     EXPECT_TRUE(parser.advance_field());
     
-    EXPECT_EQ(RadioTap::CHANNEL_PLUS,parser.current_field());
+    EXPECT_EQ(RadioTap::XCHANNEL,parser.current_field());
     EXPECT_EQ(0x1124143c00000140ULL, parser.current_option().to<uint64_t>());
 
     EXPECT_FALSE(parser.advance_field());