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#include <u.h>
#include <libc.h>
#include <ip.h>
#include "dat.h"
#include "protos.h"
enum
{
OfferTimeout= 60, /* when an offer times out */
MaxLease= 60*60, /* longest lease for dynamic binding */
MinLease= 15*60, /* shortest lease for dynamic binding */
StaticLease= 30*60, /* lease for static binding */
IPUDPHDRSIZE= 28, /* size of an IP plus UDP header */
MINSUPPORTED= 576, /* biggest IP message the client must support */
/* lengths of some bootp fields */
Maxhwlen= 16,
Maxfilelen= 128,
Maxoptlen= 312-4,
/* bootp types */
Bootrequest= 1,
Bootreply= 2,
/* bootp flags */
Fbroadcast= 1<<15
};
typedef struct Hdr Hdr;
struct Hdr
{
uchar op; /* opcode */
uchar htype; /* hardware type */
uchar hlen; /* hardware address len */
uchar hops; /* hops */
uchar xid[4]; /* a random number */
uchar secs[2]; /* elapsed since client started booting */
uchar flags[2];
uchar ciaddr[IPv4addrlen]; /* client IP address (client tells server) */
uchar yiaddr[IPv4addrlen]; /* client IP address (server tells client) */
uchar siaddr[IPv4addrlen]; /* server IP address */
uchar giaddr[IPv4addrlen]; /* gateway IP address */
uchar chaddr[Maxhwlen]; /* client hardware address */
char sname[64]; /* server host name (optional) */
char file[Maxfilelen]; /* boot file name */
uchar optmagic[4];
uchar optdata[Maxoptlen];
};
enum
{
Oca,
Osa,
Ot
};
static Field p_fields[] =
{
{"ca", Fv4ip, Oca, "client IP addr", } ,
{"sa", Fv4ip, Osa, "server IP addr", } ,
{0}
};
#define plan9opt ((ulong)(('p'<<24) | ('9'<<16) | (' '<<8) | ' '))
#define genericopt (0x63825363UL)
static Mux p_mux[] =
{
{"dhcp", genericopt,},
{"plan9bootp", plan9opt,},
{"dump", 0,},
{0}
};
static void
p_compile(Filter *f)
{
Mux *m;
if(f->op == '='){
compile_cmp(arp.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 = Ot;
return;
}
sysfatal("unknown bootp field: %s", f->s);
}
static int
p_filter(Filter *f, Msg *m)
{
Hdr *h;
h = (Hdr*)m->ps;
if(m->pe < (uchar*)h->sname)
return 0;
m->ps = h->optdata;
switch(f->subop){
case Oca:
return NetL(h->ciaddr) == f->ulv || NetL(h->yiaddr) == f->ulv;
case Osa:
return NetL(h->siaddr) == f->ulv;
case Ot:
return NetL(h->optmagic) == f->ulv;
}
return 0;
}
static char*
op(int i)
{
static char x[20];
switch(i){
case Bootrequest:
return "Req";
case Bootreply:
return "Rep";
default:
sprint(x, "%d", i);
return x;
}
}
static int
p_seprint(Msg *m)
{
Hdr *h;
ulong x;
h = (Hdr*)m->ps;
if(m->pe < (uchar*)h->sname)
return -1;
/* point past data */
m->ps = h->optdata;
/* next protocol */
m->pr = nil;
if(m->pe >= (uchar*)h->optdata){
x = NetL(h->optmagic);
demux(p_mux, x, x, m, &dump);
}
m->p = seprint(m->p, m->e, "t=%s ht=%d hl=%d hp=%d xid=%ux sec=%d fl=%4.4ux ca=%V ya=%V sa=%V ga=%V cha=%E magic=%lux",
op(h->op), h->htype, h->hlen, h->hops,
NetL(h->xid), NetS(h->secs), NetS(h->flags),
h->ciaddr, h->yiaddr, h->siaddr, h->giaddr, h->chaddr,
(ulong)NetL(h->optmagic));
if(m->pe > (uchar*)h->sname && *h->sname)
m->p = seprint(m->p, m->e, " snam=%s", h->sname);
if(m->pe > (uchar*)h->file && *h->file)
m->p = seprint(m->p, m->e, " file=%s", h->file);
return 0;
}
Proto bootp =
{
"bootp",
p_compile,
p_filter,
p_seprint,
p_mux,
"%#.8lux",
p_fields,
defaultframer
};
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