1 files changed, 112 insertions, 0 deletions
diff --git a/src/cmd/ip/snoopy/snap.c b/src/cmd/ip/snoopy/snap.c
new file mode 100644
index 00000000..1854d1d6
--- /dev/null
+++ b/src/cmd/ip/snoopy/snap.c
@@ -0,0 +1,112 @@
+/* 
+ * SNAP.
+ */
+
+#include <u.h>
+#include <libc.h>
+#include <ip.h>
+#include "dat.h"
+#include "protos.h"
+
+enum
+{
+	Oorg,
+	Oet,
+	
+	OuiEther = 0,
+	OuiCisco = 0xc,
+	OuiCisco90 = 0xf8,
+	OuiRfc2684 = 0x80c2,
+	OuiAppletalk = 0x80007,
+};
+
+static Mux p_mux[] =
+{
+	{"ip",		0x0800,	} ,
+	{"arp",		0x0806,	} ,
+	{"rarp",	0x0806,	} ,
+	{"ip6", 	0x86dd, } ,
+	{"pppoe_disc",	0x8863, },
+	{"pppoe_sess",	0x8864, },
+	{"eapol",	0x888e, },
+	{ 0 }
+};
+
+typedef struct Hdr Hdr;
+struct Hdr
+{
+	uchar org[3];
+	uchar et[2];
+};
+
+static Field p_fields[] =
+{
+	{ "org",	Fnum,	Oorg,	"org" },
+	{ "et",	Fnum,	Oet,	"et" },
+	{ 0 }
+};
+
+static void
+p_compile(Filter *f)
+{
+	Mux *m;
+
+	if(f->op == '='){
+		compile_cmp(snap.name, f, p_fields);
+		return;
+	}
+	for(m = p_mux; m->name != nil; m++){
+		if(strcmp(f->s, m->name) == 0){
+			f->pr = m->pr;
+			f->ulv = m->val;
+			f->subop = Oet;
+			return;
+		}
+	}
+	sysfatal("unknown snap field or protocol: %s", f->s);
+}
+
+static int
+p_filter(Filter *f, Msg *m)
+{
+	Hdr *h;
+
+	if(m->pe - m->ps < sizeof(Hdr))
+		return 0;
+	h = (Hdr*)m->ps;
+	m->ps += 5;
+	switch(f->subop){
+	case Oorg:
+		return f->ulv == Net3(h->org);
+	case Oet:
+		return f->ulv == NetS(h->et);
+	}
+	return 0;
+}
+
+static int
+p_seprint(Msg *m)
+{
+	Hdr *h;
+
+	if(m->pe - m->ps < sizeof(Hdr))
+		return 0;
+	h = (Hdr*)m->ps;
+	m->ps += 5;
+	demux(p_mux, NetS(h->et), NetS(h->et), m, &dump);
+
+	m->p = seprint(m->p, m->e, "org=%06x et=%04x", Net3(h->org), NetS(h->et));
+	return 0;
+}
+
+Proto snap =
+{
+	"snap",
+	p_compile,
+	p_filter,
+	p_seprint,
+	p_mux,
+	nil,
+	nil,
+	defaultframer
+};