ref: 3b7e03a30ed29ee0666c00568bf67b8179c28d12
dir: /sys/src/cmd/ip/dhcpd/ndb.c/
/*
* this currently only works for ethernet bootp's -- presotto
*/
#include <u.h>
#include <libc.h>
#include <ip.h>
#include <bio.h>
#include <ndb.h>
#include "dat.h"
static Ndb *db;
char *ndbfile;
/*
* open ndbfile as db if not already open. also check for stale data
* and reload as needed.
*/
static Ndb *
opendb(void)
{
static ulong lastcheck;
/* check no more often than once every minute */
if(db == nil) {
db = ndbopen(ndbfile);
if(db != nil)
lastcheck = now;
} else if(now >= lastcheck + 60) {
if (ndbchanged(db))
ndbreopen(db);
lastcheck = now;
}
return db;
}
Iplifc*
findlifc(uchar *ip)
{
uchar x[IPaddrlen];
Ipifc *ifc;
Iplifc *lifc;
for(ifc = ipifcs; ifc != nil; ifc = ifc->next){
for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){
if(lifc->net[0] == 0)
continue;
maskip(ip, lifc->mask, x);
if(ipcmp(x, lifc->net) == 0)
return lifc;
}
}
return nil;
}
int
forme(uchar *ip)
{
Ipifc *ifc;
Iplifc *lifc;
for(ifc = ipifcs; ifc != nil; ifc = ifc->next){
for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next)
if(ipcmp(ip, lifc->ip) == 0)
return 1;
}
return 0;
}
uchar noetheraddr[6];
static void
setipaddr(uchar *addr, char *ip)
{
if(ipcmp(addr, IPnoaddr) == 0)
parseip(addr, ip);
}
static void
setipmask(uchar *mask, char *ip)
{
if(ipcmp(mask, IPnoaddr) == 0)
parseipmask(mask, ip);
}
/*
* do an ipinfo with defaults
*/
int
lookupip(uchar *ipaddr, Info *iip, int gate)
{
char ip[32];
Ndbtuple *t, *nt;
char *attrs[32], **p;
if(opendb() == nil){
warning(1, "can't open db");
return -1;
}
p = attrs;
*p++ = "ip";
*p++ = "ipmask";
*p++ = "@ipgw";
if(!gate){
*p++ = "bootf";
*p++ = "bootf2";
*p++ = "@tftp";
*p++ = "@tftp2";
*p++ = "rootpath";
*p++ = "dhcp";
*p++ = "vendorclass";
*p++ = "ether";
*p++ = "dom";
*p++ = "@fs";
*p++ = "@auth";
}
*p = 0;
memset(iip, 0, sizeof(*iip));
snprint(ip, sizeof(ip), "%I", ipaddr);
t = ndbipinfo(db, "ip", ip, attrs, p - attrs);
if(t == nil)
return -1;
for(nt = t; nt != nil; nt = nt->entry){
if(strcmp(nt->attr, "ip") == 0)
setipaddr(iip->ipaddr, nt->val);
else
if(strcmp(nt->attr, "ipmask") == 0)
setipmask(iip->ipmask, nt->val);
else
if(strcmp(nt->attr, "fs") == 0)
setipaddr(iip->fsip, nt->val);
else
if(strcmp(nt->attr, "auth") == 0)
setipaddr(iip->auip, nt->val);
else
if(strcmp(nt->attr, "tftp") == 0)
setipaddr(iip->tftp, nt->val);
else
if(strcmp(nt->attr, "tftp2") == 0)
setipaddr(iip->tftp2, nt->val);
else
if(strcmp(nt->attr, "ipgw") == 0)
setipaddr(iip->gwip, nt->val);
else
if(strcmp(nt->attr, "ether") == 0){
/*
* this is probably wrong for machines with multiple
* ethers. bootp or dhcp requests could come from any
* of the ethers listed in the ndb entry.
*/
if(memcmp(iip->etheraddr, noetheraddr, 6) == 0)
parseether(iip->etheraddr, nt->val);
iip->indb = 1;
}
else
if(strcmp(nt->attr, "dhcp") == 0){
if(iip->dhcpgroup[0] == 0)
strncpy(iip->dhcpgroup, nt->val, sizeof(iip->dhcpgroup)-1);
}
else
if(strcmp(nt->attr, "bootf") == 0){
if(iip->bootf[0] == 0)
strncpy(iip->bootf, nt->val, sizeof(iip->bootf)-1);
}
else
if(strcmp(nt->attr, "bootf2") == 0){
if(iip->bootf2[0] == 0)
strncpy(iip->bootf2, nt->val, sizeof(iip->bootf2)-1);
}
else
if(strcmp(nt->attr, "vendor") == 0){
if(iip->vendor[0] == 0)
strncpy(iip->vendor, nt->val, sizeof(iip->vendor)-1);
}
else
if(strcmp(nt->attr, "dom") == 0){
if(iip->domain[0] == 0)
strncpy(iip->domain, nt->val, sizeof(iip->domain)-1);
}
else
if(strcmp(nt->attr, "rootpath") == 0){
if(iip->rootpath[0] == 0)
strncpy(iip->rootpath, nt->val, sizeof(iip->rootpath)-1);
}
}
ndbfree(t);
maskip(iip->ipaddr, iip->ipmask, iip->ipnet);
return 0;
}
static uchar zeroes[6];
/*
* lookup info about a client in the database. Find an address on the
* same net as riip.
*/
int
lookup(Bootp *bp, Info *iip, Info *riip)
{
Ndbtuple *t, *nt;
Ndbs s;
char *hwattr;
char *hwval, hwbuf[33];
uchar ciaddr[IPaddrlen];
if(opendb() == nil){
warning(1, "can't open db");
return -1;
}
memset(iip, 0, sizeof(*iip));
/* client knows its address? */
v4tov6(ciaddr, bp->ciaddr);
if(validip(ciaddr)){
if(lookupip(ciaddr, iip, 0) < 0) {
if (debug)
warning(0, "don't know %I", ciaddr);
return -1; /* don't know anything about it */
}
if(!samenet(riip->ipaddr, iip)){
warning(0, "%I not on %I", ciaddr, riip->ipnet);
return -1;
}
/*
* see if this is a masquerade, i.e., if the ether
* address doesn't match what we expected it to be.
*/
if(memcmp(iip->etheraddr, zeroes, 6) != 0)
if(memcmp(bp->chaddr, iip->etheraddr, 6) != 0)
warning(0, "ciaddr %I rcvd from %E instead of %E",
ciaddr, bp->chaddr, iip->etheraddr);
return 0;
}
if(bp->hlen > Maxhwlen)
return -1;
switch(bp->htype){
case 1:
hwattr = "ether";
hwval = hwbuf;
snprint(hwbuf, sizeof(hwbuf), "%E", bp->chaddr);
break;
default:
syslog(0, blog, "not ethernet %E, htype %d, hlen %d",
bp->chaddr, bp->htype, bp->hlen);
return -1;
}
/*
* use hardware address to find an ip address on
* same net as riip
*/
t = ndbsearch(db, &s, hwattr, hwval);
while(t != nil){
for(nt = t; nt != nil; nt = nt->entry){
if(strcmp(nt->attr, "ip") != 0)
continue;
if(parseip(ciaddr, nt->val) == -1)
continue;
if(!validip(ciaddr))
continue;
if(lookupip(ciaddr, iip, 0) < 0)
continue;
if(samenet(riip->ipaddr, iip)){
ndbfree(t);
return 0;
}
}
ndbfree(t);
t = ndbsnext(&s, hwattr, hwval);
}
return -1;
}
/*
* interface to ndbipinfo
*/
Ndbtuple*
lookupinfo(uchar *ipaddr, char **attr, int n)
{
char ip[64];
snprint(ip, sizeof ip, "%I", ipaddr);
return ndbipinfo(db, "ip", ip, attr, n);
}
/*
* return the ip addresses for a type of server for system ip
*/
int
lookupserver(char *attr, uchar **ipaddrs, int naddrs, Ndbtuple *t)
{
Ndbtuple *nt;
int rv = 0;
for(nt = t; rv < naddrs && nt != nil; nt = nt->entry){
if(strcmp(nt->attr, attr) != 0)
continue;
if(parseip(ipaddrs[rv], nt->val) == -1)
continue;
rv++;
}
return rv;
}
/*
* just lookup the name
*/
void
lookupname(char *val, int len, Ndbtuple *t)
{
Ndbtuple *nt;
for(nt = t; nt != nil; nt = nt->entry)
if(strcmp(nt->attr, "dom") == 0){
strncpy(val, nt->val, len-1);
val[len-1] = 0;
break;
}
}