Added DHCP and BootP constructors from uint8_t buffer. Normalized IP destination and source address getters/setters.

src/dhcp.cpp

@@ -19,6 +19,7 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
+#include <stdexcept>
 #include <cstring>
 #include <cassert>
 #include "utils.h"
@@ -36,6 +37,26 @@ Tins::DHCP::DHCP() : _size(sizeof(uint32_t) + 1) {
     hlen(6);
 }
 
+Tins::DHCP::DHCP(const uint8_t *buffer, uint32_t total_sz) : BootP(buffer, total_sz, 0) {
+    buffer += BootP::header_size();
+    total_sz -= BootP::header_size();
+    uint8_t args[2];
+    while(total_sz) {
+        for(unsigned i(0); i < 2; ++i) {
+            args[i] = *(buffer++);
+            total_sz--;
+            if(!total_sz)
+                throw std::runtime_error("Not enought size for a DHCP header in the buffer.");
+        }
+        // Not enough size for this option
+        if(total_sz < args[1])
+            throw std::runtime_error("Not enought size for a DHCP header in the buffer.");
+        add_option((Options)args[0], args[1], buffer);
+        buffer += args[1];
+        total_sz -= args[1];
+    }
+}
+
 Tins::DHCP::~DHCP() {
     while(_options.size()) {
         delete[] _options.front().value;