Restructure packet handling

diff --git a/source/host.h b/source/host.h
index ec2741d6b7127183381cb6f858b054b8d0fd5dc2..c41610fd25d4b786420b8ee030d98340020fe851 100644 (file)
--- a/source/host.h
+++ b/source/host.h
@@ -35,6 +35,7 @@ public:
        void set_name(const std::string &);
        const std::string &get_name() const { return name; }
        void set_local(bool);
+       bool is_local() const { return local; }
 
        void set_position(const Vector2 &);
        const Vector2 &get_position() const { return pos; }

diff --git a/source/netvis.cpp b/source/netvis.cpp
index 52f586456f4a51b117b40e25ea482aa2980679f2..22231b150a4b62356c312d403534fed34ff6f2ff 100644 (file)
--- a/source/netvis.cpp
+++ b/source/netvis.cpp
@@ -9,10 +9,6 @@ Distributed unter the GPL
 #include <cstdlib>
 #include <cmath>
 #include <signal.h>
-#include <netinet/ether.h>
-#include <netinet/ip.h>
-#include <netinet/tcp.h>
-#include <netinet/udp.h>
 #include <msp/core/getopt.h>
 #include <msp/debug/profilingscope.h>
 #include <msp/gl/blend.h>
@@ -23,6 +19,7 @@ Distributed unter the GPL
 #include <msp/gl/projection.h>
 #include <msp/gl/texture2d.h>
 #include <msp/gl/transform.h>
+#include <msp/io/print.h>
 #include <msp/strings/format.h>
 #include <msp/time/units.h>
 #include <msp/time/utils.h>
@@ -278,79 +275,120 @@ Port &NetVis::get_port(unsigned number)
        return *port;
 }
 
-void NetVis::capture_handler(unsigned char *user, const pcap_pkthdr *, const unsigned char *data)
+void NetVis::capture_handler(unsigned char *user, const pcap_pkthdr *cap, const unsigned char *data)
 {
        NetVis *self = reinterpret_cast<NetVis *>(user);
 
+       CaptureContext ctx;
+       ctx.cap_hdr = cap;
        const ethhdr *eth = reinterpret_cast<const ethhdr *>(data);
-       if(ntohs(eth->h_proto)==ETH_P_IP)
+       self->handle_ethernet(ctx, eth, cap->caplen);
+}
+
+void NetVis::handle_ethernet(CaptureContext &ctx, const ethhdr *eth, unsigned len)
+{
+       ctx.size = ctx.cap_hdr->len-sizeof(ethhdr);
+
+       int proto = ntohs(eth->h_proto);
+       if(proto==ETH_P_IP)
        {
                const iphdr *ip = reinterpret_cast<const iphdr *>(eth+1);
+               handle_ipv4(ctx, ip, len-sizeof(ethhdr));
+       }
+       else
+               IO::print("Unknown protocol in eth: %d\n", proto);
+}
 
-               unsigned size = ntohs(ip->tot_len);
+void NetVis::handle_ipv4(CaptureContext &ctx, const iphdr *ip, unsigned len)
+{
+       ctx.src_host = &get_host(ntohl(ip->saddr));
+       if((ntohl(ip->daddr)&0xFF)!=0xFF)
+               ctx.dst_host = &get_host(ntohl(ip->daddr));
 
-               Port *sport = 0;
-               Port *dport = 0;
-               if(ip->protocol==IPPROTO_TCP)
-               {
-                       const tcphdr *tcp = reinterpret_cast<const tcphdr *>(ip+1);
-                       sport = &self->get_port(ntohs(tcp->source));
-                       dport = &self->get_port(ntohs(tcp->dest));
-               }
-               else if(ip->protocol==IPPROTO_UDP)
-               {
-                       const udphdr *udp = reinterpret_cast<const udphdr *>(ip+1);
-                       sport = &self->get_port(ntohs(udp->source));
-                       dport = &self->get_port(ntohs(udp->dest));
-               }
+       if(ip->protocol==IPPROTO_TCP)
+       {
+               const tcphdr *tcp = reinterpret_cast<const tcphdr *>(ip+1);
+               handle_tcp(ctx, tcp, len-sizeof(iphdr));
+       }
+       else if(ip->protocol==IPPROTO_UDP)
+       {
+               const udphdr *udp = reinterpret_cast<const udphdr *>(ip+1);
+               handle_udp(ctx, udp, len-sizeof(iphdr));
+       }
+       else
+               IO::print("Unknown protocol in ip: %d\n", ip->protocol);
+}
 
-               Port *port = 0;
-               if(sport && dport)
-               {
-                       if(sport->is_registered()!=dport->is_registered())
-                       {
-                               if(sport->is_registered())
-                                       port = sport;
-                               else
-                                       port = dport;
-                       }
-                       else if(sport->get_number()<dport->get_number())
-                               port = sport;
-                       else
-                               port = dport;
-               }
-               else
-                       port = &self->get_port(0);
 
-               Host &shost = self->get_host(ntohl(ip->saddr));
-               Host *dhost = 0;
-               if((ntohl(ip->daddr)&0xFF)!=0xFF)
-                       dhost = &self->get_host(ntohl(ip->daddr));
+void NetVis::handle_tcp(CaptureContext &ctx, const tcphdr *tcp, unsigned)
+{
+       ctx.src_port = &get_port(ntohs(tcp->source));
+       ctx.dst_port = &get_port(ntohs(tcp->dest));
+       handle_packet(ctx);
+}
+
+void NetVis::handle_udp(CaptureContext &ctx, const udphdr *udp, unsigned)
+{
+       ctx.src_port = &get_port(ntohs(udp->source));
+       ctx.dst_port = &get_port(ntohs(udp->dest));
+       handle_packet(ctx);
+}
 
-               float throttle = shost.send_packet();
-               if(throttle<1)
+void NetVis::handle_packet(CaptureContext &ctx)
+{
+       Port *port = 0;
+       if(ctx.src_port && ctx.dst_port)
+       {
+               if(ctx.src_port->is_registered()!=ctx.dst_port->is_registered())
                {
-                       self->packets.push_back(new Packet(shost, dhost, port->get_color(), size));
-                       self->packets.back()->tick(-throttle*Msp::Time::sec);
+                       if(ctx.src_port->is_registered())
+                               port = ctx.src_port;
+                       else
+                               port = ctx.dst_port;
                }
+               else if(ctx.src_port->get_number()<ctx.dst_port->get_number())
+                       port = ctx.src_port;
+               else
+                       port = ctx.dst_port;
+       }
+       else
+               port = &get_port(0);
 
-               shost.add_activity(size);
-               if(dhost)
-                       dhost->add_activity(size);
-
-               if(sport)
-                       sport->add_activity(size);
-               if(dport)
-                       dport->add_activity(size);
-
-               if((ntohl(ip->saddr)&self->localnet_mask)==self->localnet)
-                       self->history->activity(0, size);
-               else if((ntohl(ip->daddr)&self->localnet_mask)==self->localnet)
-                       self->history->activity(size, 0);
+       float throttle = ctx.src_host->send_packet();
+       if(throttle<1)
+       {
+               packets.push_back(new Packet(*ctx.src_host, ctx.dst_host, port->get_color(), ctx.size));
+               packets.back()->tick(-throttle*Msp::Time::sec);
        }
+
+       ctx.src_host->add_activity(ctx.size);
+       if(ctx.dst_host)
+               ctx.dst_host->add_activity(ctx.size);
+
+       if(ctx.src_port)
+               ctx.src_port->add_activity(ctx.size);
+       if(ctx.dst_port)
+               ctx.dst_port->add_activity(ctx.size);
+
+       bool local_src = ctx.src_host->is_local();
+       bool local_dst = (ctx.dst_host && ctx.dst_host->is_local());
+       if(local_src && !local_dst)
+               history->activity(0, ctx.size);
+       else if(local_dst && !local_src)
+               history->activity(ctx.size, 0);
 }
 
 void NetVis::sighandler(int)
 {
        exit(0);
 }
+
+
+NetVis::CaptureContext::CaptureContext():
+       cap_hdr(0),
+       src_host(0),
+       src_port(0),
+       dst_host(0),
+       dst_port(0),
+       size(0)
+{ }

diff --git a/source/netvis.h b/source/netvis.h
index 46b96a58a85d3779d00e80c5010d7af5ff9e5733..68eed052f3649255d4d9ee74655e624a89327968 100644 (file)
--- a/source/netvis.h
+++ b/source/netvis.h
@@ -11,6 +11,10 @@ Distributed unter the GPL
 #include <list>
 #include <map>
 #include <pcap.h>
+#include <netinet/ether.h>
+#include <netinet/ip.h>
+#include <netinet/tcp.h>
+#include <netinet/udp.h>
 #include <msp/core/application.h>
 #include <msp/debug/profiler.h>
 #include <msp/graphics/display.h>
@@ -29,6 +33,18 @@ class Resolver;
 class NetVis: public Msp::RegisteredApplication<NetVis>
 {
 private:
+       struct CaptureContext
+       {
+               const pcap_pkthdr *cap_hdr;
+               Host *src_host;
+               Port *src_port;
+               Host *dst_host;
+               Port *dst_port;
+               unsigned size;
+
+               CaptureContext();
+       };
+
        std::string iface;
        pcap_t *pcap;
        Resolver *resolver;
@@ -67,6 +83,11 @@ private:
        void create_history_texture();
 
        static void capture_handler(unsigned char *, const pcap_pkthdr *, const unsigned char *);
+       void handle_ethernet(CaptureContext &, const ethhdr *, unsigned);
+       void handle_ipv4(CaptureContext &, const iphdr *, unsigned);
+       void handle_tcp(CaptureContext &, const tcphdr *, unsigned);
+       void handle_udp(CaptureContext &, const udphdr *, unsigned);
+       void handle_packet(CaptureContext &);
 
        void sighandler(int);
 };