implemented connection establishment with per client DHX.

1 files changed, 94 insertions, 0 deletions

diff --git a/net.c b/net.c
new file mode 100644
index 0000000..d645eb4
--- /dev/null
+++ b/net.c
@@ -0,0 +1,94 @@
+#include <u.h>
+#include <libc.h>
+#include <ip.h>
+#include <thread.h>
+#include <draw.h>
+#include <geometry.h>
+#include "dat.h"
+#include "fns.h"
+
+/* DHX */
+
+void
+dhgenpg(ulong *p, ulong *g)
+{
+	static ulong P = 97;
+	static ulong G = 71;
+
+	*p = P;
+	*g = G;
+}
+
+/*
+ * x = g^k mod p
+ */
+ulong
+dhgenkey(ulong g, ulong k, ulong p)
+{
+	ulong r, y;
+
+	y = 1;
+
+	while(k > 0){
+		r = k % 2;
+		if(r == 1)
+			y = y*g % p;
+		g = g*g % p;
+		k /= 2;
+	}
+	return y;
+}
+
+/* NetConn */
+
+NetConn *
+newnetconn(NCState s, Udphdr *u)
+{
+	NetConn *nc;
+
+	nc = emalloc(sizeof(NetConn));
+	memset(nc, 0, sizeof(NetConn));
+	if(u != nil)
+		memmove(&nc->udp, u, Udphdrsize);
+	nc->state = s;
+
+	return nc;
+}
+
+void
+delnetconn(NetConn *nc)
+{
+	free(nc);
+}
+
+/* Frame */
+
+Frame *
+newframe(Frame *pf, u8int type, u32int seq, u32int ack, u16int len, uchar *data)
+{
+	Frame *f;
+
+	f = emalloc(sizeof(Frame)+len);
+	f->id = ProtocolID;
+	f->type = type;
+	if(pf != nil){
+		memmove(&f->udp, &pf->udp, Udphdrsize);
+		f->seq = pf->seq+1;
+		f->ack = pf->seq;
+	}else{
+		memset(&f->udp, 0, Udphdrsize);
+		f->seq = seq;
+		f->ack = ack;
+	}
+	f->len = len;
+	if(data != nil)
+		memmove(f->data, data, f->len);
+
+	return f;
+}
+
+void
+delframe(Frame *f)
+{
+	free(f);
+}