Subversion Repositories planix.SVN

#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(bootp.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,
};