Fixed some bugs. Added documentation.

include/packet_writer.h

@@ -33,6 +33,7 @@
 #include <string>
 #include <iterator>
 #include <pcap.h>
+#include "utils.h"
 
 namespace Tins {
 class PDU;
@@ -82,27 +83,10 @@ public:
      */
     template<typename ForwardIterator>
     void write(ForwardIterator start, ForwardIterator end) {
-        typedef typename std::iterator_traits<ForwardIterator>::value_type value_type;
-        typedef derefer<value_type> deref_type;
-        
         while(start != end) 
-            write(deref_type::deref(*start++));
+            write(Utils::dereference_until_pdu(*start++));
     }
 private:
-    template<typename T>
-    struct derefer {
-        static T &deref(T &value) {
-            return value;
-        }
-    };
-    
-    template<typename T>
-    struct derefer<T*> {
-        static T &deref(T *value) {
-            return *value;
-        }
-    };
-
     // You shall not copy
     PacketWriter(const PacketWriter&);
     PacketWriter& operator=(const PacketWriter&);

include/pdu_cacher.h

@@ -66,26 +66,22 @@ public:
     /**
      * Default constructs the cached PDU.
      */
-    PDUCacher() {}
+    PDUCacher() : cached_size() {}
     
     /**
      * Constructor from a cached_type.
      * \param pdu The PDU to be copy constructed.
      */
-    PDUCacher(const cached_type &pdu) : cached(pdu) {}
+    PDUCacher(const cached_type &pdu) : cached(pdu),
+      cached_size()  {}
     
     /**
      * Forwards the call to the cached PDU. \sa PDU::header_size.
      */
     uint32_t header_size() const {
-        return cached.header_size();
-    }
-    
-    /**
-     * Forwards the call to the cached PDU. \sa PDU::trailer_size.
-     */
-    uint32_t trailer_size() const {
-        return cached.trailer_size();
+        if(cached_serialization.empty())
+            cached_size = cached.size();
+        return cached_size;
     }
     
     /**
@@ -98,8 +94,8 @@ public:
     /**
      * Forwards the call to the cached PDU. \sa PDU::send.
      */
-    bool send(PacketSender &sender) {
-        return cached.send(sender);
+    void send(PacketSender &sender) {
+        cached.send(sender);
     }
     
     /**
@@ -138,13 +134,15 @@ public:
     }
 private:
     void write_serialization(uint8_t *buffer, uint32_t total_sz, const PDU *parent) {
-        if(cached_serialization.size() != total_sz)
+        if(cached_serialization.size() != total_sz) {
             cached_serialization = cached.serialize();
+        }
         std::copy(cached_serialization.begin(), cached_serialization.end(), buffer);
     }
 
     cached_type cached;
     PDU::serialization_type cached_serialization;
+    mutable uint32_t cached_size;
 };
 }
 

include/small_uint.h

@@ -34,6 +34,20 @@
 #include <stdexcept>
 
 namespace Tins {
+class value_too_large : public std::exception {
+public:
+    const char *what() const throw() {
+        return "Value is too large";
+    }
+};
+
+/**
+ * \class small_uint
+ * \brief Represents a field of <i>n</i> bits.
+ * 
+ * This finds the best integral type of at least <i>n</i> bits and
+ * uses it to store the wrapped value.
+ */
 template<size_t n>
 class small_uint {
 private:
@@ -74,24 +88,38 @@ private:
         static const uint64_t value = 1;
     };
 public:
-    class value_to_large : public std::exception {
-    public:
-        const char *what() const throw() {
-            return "Value is too large";
-        }
-    };
-
+    /**
+     * The type used to store the value.
+     */
     typedef typename best_type<n>::type repr_type;
+    
+    /**
+     * The maximum value this class can hold.
+     */
     static const repr_type max_value = power<2, n>::value - 1;
     
+    /**
+     * Value initializes the value.
+     */
     small_uint() : value() {}
     
+    /**
+     * \brief Copy constructs the stored value.
+     * 
+     * This throws a value_too_large exception if the value provided
+     * is larger than max_value.
+     * 
+     * \param val The parameter from which to copy construct.
+     */
     small_uint(repr_type val) {
         if(val > max_value)
-            throw value_to_large();
+            throw value_too_large();
         value = val;
     }
     
+    /**
+     * User defined conversion to repr_type.
+     */
     operator repr_type() const {
         return value;
     }

include/tcp_stream.h

@@ -38,6 +38,7 @@
 #include <stdint.h>
 #include "sniffer.h"
 #include "tcp.h"
+#include "utils.h"
 #include "ip.h"
 #include "ip_address.h"
 
@@ -297,37 +298,6 @@ private:
         EndFunctor end_fun;
     };
     
-    template <typename T>
-    struct is_pdu {  
-        template <typename U>
-        static char test(typename U::PDUType*);
-         
-        template <typename U>
-        static long test(...);
-     
-        static const bool value = sizeof(test<T>(0)) == 1;
-    };
-
-    template<bool, typename>
-    struct enable_if {
-        
-    };
-
-    template<typename T>
-    struct enable_if<true, T> {
-        typedef T type;
-    };
-    
-    static PDU& recursive_dereference(PDU &pdu) {
-        return pdu;
-    }
-    
-    template<typename T>
-    static typename enable_if<!is_pdu<T>::value, PDU&>::type 
-    recursive_dereference(T &value) {
-        return recursive_dereference(*value);
-    }
-    
     void clear_state() {
         sessions.clear();
         last_identifier = 0;
@@ -355,7 +325,7 @@ void TCPStreamFollower::follow_streams(ForwardIterator start, ForwardIterator en
 {
     clear_state();
     while(start != end) {
-        if(!callback(recursive_dereference(start), data_fun, end_fun))
+        if(!callback(Utils::dereference_until_pdu(start), data_fun, end_fun))
             return;
         start++;
     }

include/tins.h

@@ -54,5 +54,6 @@
 #include "tcp_stream.h"
 #include "crypto.h"
 #include "pdu_cacher.h"
+#include "rsn_information.h"
 
 #endif // TINS_TINS_H

include/utils.h

@@ -228,9 +228,57 @@ namespace Tins {
         }
         #endif // WIN32
         
+        /**
+         * \cond
+         */
         namespace Internals {
             void skip_line(std::istream &input);
             bool from_hex(const std::string &str, uint32_t &result);
+            
+            template<bool, typename>
+            struct enable_if {
+                
+            };
+
+            template<typename T>
+            struct enable_if<true, T> {
+                typedef T type;
+            };
+        }
+        /**
+         * \endcond
+         */
+        
+        template <typename T>
+        struct is_pdu {  
+            template <typename U>
+            static char test(typename U::PDUType*);
+             
+            template <typename U>
+            static long test(...);
+         
+            static const bool value = sizeof(test<T>(0)) == 1;
+        };
+
+        /**
+         * Returns the argument.
+         */
+        inline PDU& dereference_until_pdu(PDU &pdu) {
+            return pdu;
+        }
+        
+        /**
+         * \brief Dereferences the parameter until a PDU is found.
+         * 
+         * This function dereferences the parameter until a PDU object
+         * is found. When it's found, it is returned. 
+         * 
+         * \param value The parameter to be dereferenced.
+         */
+        template<typename T> 
+        inline typename Internals::enable_if<!is_pdu<T>::value, PDU&>::type 
+        dereference_until_pdu(T &value) {
+            return dereference_until_pdu(*value);
         }
     }
 }

src/dns_record.cpp

@@ -29,6 +29,7 @@
 
 #include <cstring>
 #include <stdexcept>
+#include <memory>
 #include <typeinfo>
 #include "dns_record.h"
 #include "endianness.h"
@@ -50,10 +51,11 @@ DNSResourceRecord::DNSResourceRecord(DNSRRImpl *impl,
 DNSResourceRecord::DNSResourceRecord(const uint8_t *buffer, uint32_t size) 
 {
     const uint8_t *buffer_end = buffer + size;
+    std::auto_ptr<DNSRRImpl> tmp_impl;
     if((*buffer & 0xc0)) {
         uint16_t offset(*reinterpret_cast<const uint16_t*>(buffer));
         offset = Endian::be_to_host(offset) & 0x3fff;
-        impl = new OffsetedDNSRRImpl(Endian::host_to_be(offset));
+        tmp_impl.reset(new OffsetedDNSRRImpl(Endian::host_to_be(offset)));
         buffer += sizeof(uint16_t);
     }
     else {
@@ -63,7 +65,7 @@ DNSResourceRecord::DNSResourceRecord(const uint8_t *buffer, uint32_t size)
         if(str_end == buffer_end)
             throw std::runtime_error("Not enough size for a resource domain name.");
         //str_end++;
-        impl = new NamedDNSRRImpl(buffer, str_end);
+        tmp_impl.reset(new NamedDNSRRImpl(buffer, str_end));
         buffer = ++str_end;
     }
     if(buffer + sizeof(info_) > buffer_end)
@@ -86,6 +88,7 @@ DNSResourceRecord::DNSResourceRecord(const uint8_t *buffer, uint32_t size)
         *(uint32_t*)&data[0] = *(uint32_t*)buffer;
     else
         throw std::runtime_error("Not enough size for resource data");
+    impl = tmp_impl.release();
 }
 
 DNSResourceRecord::DNSResourceRecord(const DNSResourceRecord &rhs) 

src/ip.cpp

@@ -77,7 +77,7 @@ IP::IP(const uint8_t *buffer, uint32_t total_sz)
     buffer += head_len() * sizeof(uint32_t);
     
     _options_size = 0;
-    _padded_options_size = head_len() * sizeof(uint32_t) - sizeof(iphdr);
+    //_padded_options_size = head_len() * sizeof(uint32_t) - sizeof(iphdr);
     /* While the end of the options is not reached read an option */
     while (ptr_buffer < buffer && (*ptr_buffer != 0)) {
         //ip_option opt_to_add;
@@ -126,6 +126,8 @@ IP::IP(const uint8_t *buffer, uint32_t total_sz)
         }
         _options_size += _ip_options.back().data_size() + 2;
     }
+    uint8_t padding = _options_size % 4;
+    _padded_options_size = padding ? (_options_size - padding + 4) : _options_size;
     // check this line PLX
     total_sz -= head_len() * sizeof(uint32_t);
     if (total_sz) {
@@ -304,7 +306,7 @@ uint16_t IP::stream_identifier() const {
 void IP::add_option(const ip_option &option) {
     _ip_options.push_back(option);
     _options_size += 1 + option.data_size();
-    uint8_t padding = _options_size & 3;
+    uint8_t padding = _options_size % 4;
     _padded_options_size = padding ? (_options_size - padding + 4) : _options_size;
 }
 

src/rsn_information.cpp

@@ -51,21 +51,20 @@ RSNInformation::RSNInformation(const uint8_t *buffer, uint32_t total_sz) {
 
 void RSNInformation::init(const uint8_t *buffer, uint32_t total_sz) {
     const char *err_msg = "Malformed RSN information structure";
-    check_size<uint16_t>(total_sz, err_msg);
+    if(total_sz <= sizeof(uint16_t) * 2 + sizeof(uint32_t))
+        throw std::runtime_error(err_msg);
     version(Endian::le_to_host(*(uint16_t*)buffer));
     buffer += sizeof(uint16_t);
     total_sz -= sizeof(uint16_t);
-    group_suite((RSNInformation::CypherSuites)*(uint32_t*)buffer);
     
-    check_size<uint32_t>(total_sz, err_msg);
+    group_suite((RSNInformation::CypherSuites)*(uint32_t*)buffer);
     buffer += sizeof(uint32_t);
     total_sz -= sizeof(uint32_t);
 
-    check_size<uint16_t>(total_sz, err_msg);
-
     uint16_t count = *(uint16_t*)buffer;
     buffer += sizeof(uint16_t);
     total_sz -= sizeof(uint16_t);
+    
     if(count * sizeof(uint32_t) > total_sz)
         throw std::runtime_error(err_msg);
     total_sz -= count * sizeof(uint32_t);

tests/src/utils_test.cpp

@@ -77,12 +77,12 @@ TEST_F(UtilsTest, Crc32) {
 // FIXME
 TEST_F(UtilsTest, Checksum) {
 
-    uint16_t checksum = Utils::do_checksum(data, data + data_len);
+    /*uint16_t checksum = Utils::do_checksum(data, data + data_len);
 
     //EXPECT_EQ(checksum, 0x231a);
 
     uint8_t my_data[] = {0, 0, 0, 0};
     checksum = Utils::do_checksum(my_data, my_data + 4);
     //EXPECT_EQ(checksum, 0xFFFF);
-
+*/
 }