ref: 4d4107b38547c7f9f135cc22d3a29fcbad4a8c34
dir: /sys/src/cmd/ndb/cs.c/
#include <u.h>
#include <libc.h>
#include <auth.h>
#include <fcall.h>
#include <bio.h>
#include <ctype.h>
#include <ndb.h>
#include <ip.h>
#include <String.h>
enum
{
Nreply= 20,
Maxreply= 256,
Maxrequest= 128,
Maxpath= 128,
Maxfdata= 8192,
Maxhost= 64, /* maximum host name size */
Maxservice= 64, /* maximum service name size */
Maxactive= 200, /* maximum number of active slave procs */
Qdir= 0,
Qcs= 1,
};
typedef struct Mfile Mfile;
typedef struct Mlist Mlist;
typedef struct Network Network;
typedef struct Flushreq Flushreq;
typedef struct Job Job;
int vers; /* incremented each clone/attach */
struct Mfile
{
int busy; /* fid in use */
int ref; /* cleanup when drops to zero */
char *user;
Qid qid;
int fid;
/*
* current request
*/
char *net;
char *host;
char *serv;
char *rem;
/*
* result of the last lookup
*/
Network *nextnet;
int nreply;
char *reply[Nreply];
int replylen[Nreply];
};
struct Mlist
{
Mlist *next;
Mfile mf;
};
/*
* active requests
*/
struct Job
{
Job *next;
int flushed;
Fcall request;
Fcall reply;
};
QLock joblock;
Job *joblist;
Mlist *mlist;
int mfd[2];
int debug;
jmp_buf masterjmp; /* return through here after a slave process has been created */
int *isslave; /* *isslave non-zero means this is a slave process */
long active; /* number of active slaves */
char *dbfile;
Ndb *db, *netdb;
char *csuser;
void rversion(Job*);
void rflush(Job*);
void rattach(Job*, Mfile*);
char* rwalk(Job*, Mfile*);
void ropen(Job*, Mfile*);
void rcreate(Job*, Mfile*);
void rread(Job*, Mfile*);
void rwrite(Job*, Mfile*);
void rclunk(Job*, Mfile*);
void rremove(Job*, Mfile*);
void rstat(Job*, Mfile*);
void rwstat(Job*, Mfile*);
void rauth(Job*);
void sendmsg(Job*, char*);
void error(char*);
void mountinit(char*, char*);
void io(void);
void ndbinit(void);
void netinit(int);
void netadd(char*);
char *genquery(Mfile*, char*);
char* ipinfoquery(Mfile*, char**, int);
int needproto(Network*, Ndbtuple*);
int lookup(Mfile*);
void ipid(void);
void readipinterfaces(void);
void* emalloc(int);
char* estrdup(char*);
Job* newjob(void);
void freejob(Job*);
void setext(char*, int, char*);
void cleanmf(Mfile*);
QLock dblock; /* mutex on database operations */
QLock netlock; /* mutex for netinit() */
char *logfile = "cs";
char mntpt[Maxpath];
char netndb[Maxpath];
/*
* Network specific translators
*/
Ndbtuple* iplookup(Network*, char*, char*);
char* iptrans(Ndbtuple*, Network*, char*, char*, int);
Ndbtuple* telcolookup(Network*, char*, char*);
char* telcotrans(Ndbtuple*, Network*, char*, char*, int);
Ndbtuple* dnsiplookup(char*, Ndbs*, int);
Ndbtuple* myipinfo(Ndb *db, char **list, int n);
struct Network
{
char *net;
Ndbtuple *(*lookup)(Network*, char*, char*);
char *(*trans)(Ndbtuple*, Network*, char*, char*, int);
char considered; /* flag: ignored for "net!"? */
char fasttimeout; /* flag. was for IL */
char ipvers; /* flag: V4, V6 */
Network *next;
};
enum {
Ntcp = 1,
V4 = 1,
V6 = 2,
};
/*
* net doesn't apply to (r)udp, icmp(v6), or telco (for speed).
*/
Network network[] = {
{ "il", iplookup, iptrans, 0, 1, V4, },
{ "tcp", iplookup, iptrans, 0, 0, V4|V6, },
{ "il", iplookup, iptrans, 0, 0, V4, },
{ "udp", iplookup, iptrans, 1, 0, V4|V6, },
{ "icmp", iplookup, iptrans, 1, 0, V4, },
{ "icmpv6", iplookup, iptrans, 1, 0, V6, },
{ "rudp", iplookup, iptrans, 1, 0, V4, },
{ "ssh", iplookup, iptrans, 1, 0, V4|V6, },
{ "telco", telcolookup, telcotrans, 1, 0, 0, },
{ 0 },
};
QLock ipifclock;
Ipifc *ipifcs;
int confipvers;
int dnsipvers;
int lookipvers = V4|V6;
char *mysysname;
Network *netlist; /* networks ordered by preference */
Network *last;
static void
nstrcpy(char *to, char *from, int len)
{
strncpy(to, from, len);
to[len-1] = 0;
}
void
usage(void)
{
fprint(2, "usage: %s [-46dn] [-f ndb-file] [-x netmtpt]\n", argv0);
exits("usage");
}
void
main(int argc, char *argv[])
{
int justsetname;
char ext[Maxpath], servefile[Maxpath];
justsetname = 0;
setnetmtpt(mntpt, sizeof(mntpt), nil);
ext[0] = 0;
ARGBEGIN{
case '4':
lookipvers = V4;
break;
case '6':
lookipvers = V6;
break;
case 'd':
debug = 1;
break;
case 'f':
dbfile = EARGF(usage());
break;
case 'n':
justsetname = 1;
break;
case 'x':
setnetmtpt(mntpt, sizeof(mntpt), EARGF(usage()));
setext(ext, sizeof(ext), mntpt);
break;
}ARGEND
USED(argc);
USED(argv);
snprint(netndb, sizeof(netndb), "%s/ndb", mntpt);
fmtinstall('E', eipfmt);
fmtinstall('I', eipfmt);
fmtinstall('M', eipfmt);
fmtinstall('F', fcallfmt);
ndbinit();
netinit(0);
if(!justsetname){
snprint(servefile, sizeof(servefile), "#s/cs%s", ext);
unmount(servefile, mntpt);
remove(servefile);
rfork(RFREND|RFNOTEG);
csuser = estrdup(getuser());
mountinit(servefile, mntpt);
io();
}
exits(0);
}
/*
* if a mount point is specified, set the cs extention to be the mount point
* with '_'s replacing '/'s
*/
void
setext(char *ext, int n, char *p)
{
int i, c;
n--;
for(i = 0; i < n; i++){
c = p[i];
if(c == 0)
break;
if(c == '/')
c = '_';
ext[i] = c;
}
ext[i] = 0;
}
void
mountinit(char *service, char *mntpt)
{
int f;
int p[2];
char buf[32];
if(pipe(p) < 0)
error("pipe failed");
/*
* make a /srv/cs
*/
f = create(service, OWRITE|ORCLOSE, 0666);
if(f < 0)
error(service);
snprint(buf, sizeof(buf), "%d", p[1]);
if(write(f, buf, strlen(buf)) != strlen(buf))
error("write /srv/cs");
switch(rfork(RFFDG|RFPROC|RFNAMEG)){
case 0:
close(p[1]);
procsetname("%s", mntpt);
break;
case -1:
error("fork failed");
default:
/*
* put ourselves into the file system
*/
close(p[0]);
if(mount(p[1], -1, mntpt, MAFTER, "") < 0)
error("mount failed");
_exits(0);
}
mfd[0] = mfd[1] = p[0];
}
void
ndbinit(void)
{
db = ndbopen(dbfile);
if(db == nil)
error("can't open network database");
for(netdb = db; netdb != nil; netdb = netdb->next)
if(strcmp(netdb->file, netndb) == 0)
return;
netdb = ndbopen(netndb);
if(netdb != nil){
netdb->nohash = 1;
db = ndbcat(netdb, db);
}
}
Mfile*
newfid(int fid)
{
Mlist *f, *ff;
Mfile *mf;
ff = nil;
for(f = mlist; f != nil; f = f->next)
if(f->mf.busy && f->mf.fid == fid)
return &f->mf;
else if(ff == nil && !f->mf.busy && !f->mf.ref)
ff = f;
if(ff == nil){
ff = emalloc(sizeof *f);
ff->next = mlist;
mlist = ff;
}
mf = &ff->mf;
memset(mf, 0, sizeof *mf);
mf->fid = fid;
return mf;
}
Job*
newjob(void)
{
Job *job;
job = emalloc(sizeof *job);
qlock(&joblock);
job->next = joblist;
joblist = job;
job->request.tag = -1;
qunlock(&joblock);
return job;
}
void
freejob(Job *job)
{
Job **l;
qlock(&joblock);
for(l = &joblist; *l != nil; l = &(*l)->next){
if((*l) == job){
*l = job->next;
break;
}
}
qunlock(&joblock);
free(job);
}
void
flushjob(int tag)
{
Job *job;
qlock(&joblock);
for(job = joblist; job != nil; job = job->next){
if(job->request.tag == tag && job->request.type != Tflush){
job->flushed = 1;
break;
}
}
qunlock(&joblock);
}
void
io(void)
{
long n;
Mfile *mf;
int slaveflag;
uchar mdata[IOHDRSZ + Maxfdata];
Job *job;
/*
* if we ask dns to fulfill requests,
* a slave process is created to wait for replies. The
* master process returns immediately via a longjmp
* through 'masterjmp'.
*
* *isslave is a pointer into the call stack to a variable
* that tells whether or not the current process is a slave.
*/
slaveflag = 0; /* init slave variable */
isslave = &slaveflag;
setjmp(masterjmp);
for(;;){
n = read9pmsg(mfd[0], mdata, sizeof mdata);
if(n < 0)
error("mount read");
if(n == 0)
break;
job = newjob();
if(convM2S(mdata, n, &job->request) != n){
syslog(1, logfile, "format error %ux %ux %ux %ux %ux",
mdata[0], mdata[1], mdata[2], mdata[3], mdata[4]);
freejob(job);
break;
}
qlock(&dblock);
mf = newfid(job->request.fid);
if(debug)
syslog(0, logfile, "%F", &job->request);
switch(job->request.type){
default:
syslog(1, logfile, "unknown request type %d", job->request.type);
break;
case Tversion:
rversion(job);
break;
case Tauth:
rauth(job);
break;
case Tflush:
rflush(job);
break;
case Tattach:
rattach(job, mf);
break;
case Twalk:
rwalk(job, mf);
break;
case Topen:
ropen(job, mf);
break;
case Tcreate:
rcreate(job, mf);
break;
case Tread:
rread(job, mf);
break;
case Twrite:
rwrite(job, mf);
break;
case Tclunk:
rclunk(job, mf);
break;
case Tremove:
rremove(job, mf);
break;
case Tstat:
rstat(job, mf);
break;
case Twstat:
rwstat(job, mf);
break;
}
qunlock(&dblock);
freejob(job);
/*
* slave processes die after replying
*/
if(*isslave){
if(debug)
syslog(0, logfile, "slave death %d", getpid());
adec(&active);
_exits(0);
}
}
}
void
rversion(Job *job)
{
if(job->request.msize > IOHDRSZ + Maxfdata)
job->reply.msize = IOHDRSZ + Maxfdata;
else
job->reply.msize = job->request.msize;
if(strncmp(job->request.version, "9P2000", 6) != 0)
sendmsg(job, "unknown 9P version");
else{
job->reply.version = "9P2000";
sendmsg(job, nil);
}
}
void
rauth(Job *job)
{
sendmsg(job, "cs: authentication not required");
}
/*
* don't flush till all the slaves are done
*/
void
rflush(Job *job)
{
flushjob(job->request.oldtag);
sendmsg(job, nil);
}
void
rattach(Job *job, Mfile *mf)
{
if(mf->busy == 0){
mf->busy = 1;
mf->user = estrdup(job->request.uname);
}
mf->qid.vers = vers++;
mf->qid.type = QTDIR;
mf->qid.path = 0LL;
job->reply.qid = mf->qid;
sendmsg(job, nil);
}
char*
rwalk(Job *job, Mfile *mf)
{
char *err;
char **elems;
int nelems;
int i;
Mfile *nmf;
Qid qid;
err = nil;
nmf = nil;
elems = job->request.wname;
nelems = job->request.nwname;
job->reply.nwqid = 0;
if(job->request.newfid != job->request.fid){
/* clone fid */
nmf = newfid(job->request.newfid);
if(nmf->busy){
nmf = nil;
err = "clone to used channel";
goto send;
}
*nmf = *mf;
nmf->user = estrdup(mf->user);
nmf->fid = job->request.newfid;
nmf->qid.vers = vers++;
mf = nmf;
}
/* else nmf will be nil */
qid = mf->qid;
if(nelems > 0){
/* walk fid */
for(i=0; i<nelems && i<MAXWELEM; i++){
if((qid.type & QTDIR) == 0){
err = "not a directory";
break;
}
if(strcmp(elems[i], "..") == 0 || strcmp(elems[i], ".") == 0){
qid.type = QTDIR;
qid.path = Qdir;
Found:
job->reply.wqid[i] = qid;
job->reply.nwqid++;
continue;
}
if(strcmp(elems[i], "cs") == 0){
qid.type = QTFILE;
qid.path = Qcs;
goto Found;
}
err = "file does not exist";
break;
}
}
send:
if(nmf != nil && (err!=nil || job->reply.nwqid<nelems)){
cleanmf(nmf);
free(nmf->user);
nmf->user = nil;
nmf->busy = 0;
nmf->fid = 0;
}
if(err == nil)
mf->qid = qid;
sendmsg(job, err);
return err;
}
void
ropen(Job *job, Mfile *mf)
{
int mode;
char *err;
err = nil;
mode = job->request.mode;
if(mf->qid.type & QTDIR){
if(mode)
err = "permission denied";
}
job->reply.qid = mf->qid;
job->reply.iounit = 0;
sendmsg(job, err);
}
void
rcreate(Job *job, Mfile *mf)
{
USED(mf);
sendmsg(job, "creation permission denied");
}
void
rread(Job *job, Mfile *mf)
{
int i, n, cnt;
long off, toff, clock;
Dir dir;
uchar buf[Maxfdata];
char *err;
n = 0;
err = nil;
off = job->request.offset;
cnt = job->request.count;
mf->ref++;
if(mf->qid.type & QTDIR){
clock = time(0);
if(off == 0){
memset(&dir, 0, sizeof dir);
dir.name = "cs";
dir.qid.type = QTFILE;
dir.qid.vers = vers;
dir.qid.path = Qcs;
dir.mode = 0666;
dir.length = 0;
dir.uid = mf->user;
dir.gid = mf->user;
dir.muid = mf->user;
dir.atime = clock; /* wrong */
dir.mtime = clock; /* wrong */
n = convD2M(&dir, buf, sizeof buf);
}
job->reply.data = (char*)buf;
goto send;
}
for(;;){
/* look for an answer at the right offset */
toff = 0;
for(i = 0; mf->reply[i] != nil && i < mf->nreply; i++){
n = mf->replylen[i];
if(off < toff + n)
break;
toff += n;
}
if(i < mf->nreply)
break; /* got something to return */
/* try looking up more answers */
if(lookup(mf) == 0 || job->flushed){
/* no more */
n = 0;
goto send;
}
}
/* give back a single reply (or part of one) */
job->reply.data = mf->reply[i] + (off - toff);
if(cnt > toff - off + n)
n = toff - off + n;
else
n = cnt;
send:
job->reply.count = n;
sendmsg(job, err);
if(--mf->ref == 0 && mf->busy == 0)
cleanmf(mf);
}
void
cleanmf(Mfile *mf)
{
int i;
if(mf->net != nil){
free(mf->net);
mf->net = nil;
}
if(mf->host != nil){
free(mf->host);
mf->host = nil;
}
if(mf->serv != nil){
free(mf->serv);
mf->serv = nil;
}
if(mf->rem != nil){
free(mf->rem);
mf->rem = nil;
}
for(i = 0; i < mf->nreply; i++){
free(mf->reply[i]);
mf->reply[i] = nil;
mf->replylen[i] = 0;
}
mf->nreply = 0;
mf->nextnet = netlist;
}
void
rwrite(Job *job, Mfile *mf)
{
int cnt, n;
char *err;
char *field[4];
char curerr[64];
err = nil;
cnt = job->request.count;
if(mf->qid.type & QTDIR){
err = "can't write directory";
goto send;
}
if(cnt >= Maxrequest){
err = "request too long";
goto send;
}
job->request.data[cnt] = 0;
if(strcmp(mf->user, "none") == 0 || strcmp(mf->user, csuser) != 0)
goto query; /* skip special commands if not owner */
/*
* toggle debugging
*/
if(strncmp(job->request.data, "debug", 5)==0){
debug ^= 1;
syslog(1, logfile, "debug %d", debug);
goto send;
}
/*
* toggle ipv4 lookups
*/
if(strncmp(job->request.data, "ipv4", 4)==0){
lookipvers ^= V4;
syslog(1, logfile, "ipv4lookups %d", (lookipvers & V4) != 0);
goto send;
}
/*
* toggle ipv6 lookups
*/
if(strncmp(job->request.data, "ipv6", 4)==0){
lookipvers ^= V6;
syslog(1, logfile, "ipv6lookups %d", (lookipvers & V6) != 0);
goto send;
}
/*
* add networks to the default list
*/
if(strncmp(job->request.data, "add ", 4)==0){
if(job->request.data[cnt-1] == '\n')
job->request.data[cnt-1] = 0;
netadd(job->request.data+4);
readipinterfaces();
goto send;
}
/*
* refresh all state
*/
if(strncmp(job->request.data, "refresh", 7)==0){
netinit(1);
goto send;
}
query:
if(mf->ref){
err = "query already in progress";
goto send;
}
mf->ref++;
/* start transaction with a clean slate */
cleanmf(mf);
/*
* look for a general query
*/
if(*job->request.data == '!'){
err = genquery(mf, job->request.data+1);
goto done;
}
if(debug)
syslog(0, logfile, "write %s", job->request.data);
/*
* break up name
*/
n = getfields(job->request.data, field, 4, 1, "!");
switch(n){
case 1:
mf->net = estrdup("net");
mf->host = estrdup(field[0]);
break;
case 4:
mf->rem = estrdup(field[3]);
/* fall through */
case 3:
mf->serv = estrdup(field[2]);
/* fall through */
case 2:
mf->host = estrdup(field[1]);
mf->net = estrdup(field[0]);
break;
}
/*
* do the first net worth of lookup
*/
if(lookup(mf) == 0){
rerrstr(curerr, sizeof curerr);
err = curerr;
}
done:
if(--mf->ref == 0 && mf->busy == 0)
cleanmf(mf);
send:
job->reply.count = cnt;
sendmsg(job, err);
}
void
rclunk(Job *job, Mfile *mf)
{
if(mf->ref == 0)
cleanmf(mf);
free(mf->user);
mf->user = nil;
mf->fid = 0;
mf->busy = 0;
sendmsg(job, nil);
}
void
rremove(Job *job, Mfile *mf)
{
USED(mf);
sendmsg(job, "remove permission denied");
}
void
rstat(Job *job, Mfile *mf)
{
Dir dir;
uchar buf[IOHDRSZ+Maxfdata];
memset(&dir, 0, sizeof dir);
if(mf->qid.type & QTDIR){
dir.name = ".";
dir.mode = DMDIR|0555;
} else {
dir.name = "cs";
dir.mode = 0666;
}
dir.qid = mf->qid;
dir.length = 0;
dir.uid = mf->user;
dir.gid = mf->user;
dir.muid = mf->user;
dir.atime = dir.mtime = time(0);
job->reply.nstat = convD2M(&dir, buf, sizeof buf);
job->reply.stat = buf;
sendmsg(job, nil);
}
void
rwstat(Job *job, Mfile *mf)
{
USED(mf);
sendmsg(job, "wstat permission denied");
}
void
sendmsg(Job *job, char *err)
{
int n;
uchar mdata[IOHDRSZ + Maxfdata];
char ename[ERRMAX];
if(err){
job->reply.type = Rerror;
snprint(ename, sizeof(ename), "cs: %s", err);
job->reply.ename = ename;
}else{
job->reply.type = job->request.type+1;
}
job->reply.tag = job->request.tag;
n = convS2M(&job->reply, mdata, sizeof mdata);
if(n == 0){
syslog(1, logfile, "sendmsg convS2M of %F returns 0", &job->reply);
abort();
}
qlock(&joblock);
if(job->flushed == 0)
if(write(mfd[1], mdata, n)!=n)
error("mount write");
qunlock(&joblock);
if(debug)
syslog(0, logfile, "%F %d", &job->reply, n);
}
void
error(char *s)
{
syslog(1, logfile, "%s: %r", s);
_exits(0);
}
static uchar loopbacknet[IPaddrlen] = {
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0xff, 0xff,
127, 0, 0, 0
};
static uchar loopbackmask[IPaddrlen] = {
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff,
0xff, 0, 0, 0
};
static uchar loopback6[IPaddrlen] = {
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0, 0,
0, 0, 0, 1
};
void
readipinterfaces(void)
{
uchar mynet[IPaddrlen];
Ipifc *ifc;
Iplifc *lifc;
int conf, dns;
conf = dns = 0;
qlock(&ipifclock);
ipifcs = readipifc(mntpt, ipifcs, -1);
for(ifc = ipifcs; ifc != nil; ifc = ifc->next){
for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){
if(ipcmp(lifc->ip, IPnoaddr) == 0)
continue;
if(isv4(lifc->ip)){
conf |= V4;
maskip(lifc->ip, loopbackmask, mynet);
if(ipcmp(mynet, loopbacknet) == 0)
continue;
dns |= V4;
} else {
conf |= V6;
if(ISIPV6LINKLOCAL(lifc->ip))
continue;
if(ipcmp(lifc->ip, loopback6) == 0)
continue;
dns |= V6;
}
}
}
qunlock(&ipifclock);
confipvers = conf;
dnsipvers = dns;
}
/*
* get the system name
*/
void
ipid(void)
{
char eaddr[16], buf[Maxpath];
uchar addr[6];
Ndbtuple *t, *tt;
char *p, *attr;
Ndbs s;
int f, n;
Dir *d;
if(mysysname != nil)
return;
/*
* environment has priority.
*
* on the sgi power the default system name
* is the ip address. ignore that.
*
*/
p = getenv("sysname");
if(p != nil && *p != 0){
attr = ipattr(p);
if(strcmp(attr, "ip") != 0) {
mysysname = p;
goto setsys;
}
free(p);
}
/* try configured interfaces */
attr = "sys";
t = s.t = myipinfo(db, &attr, 1);
if(t != nil)
goto found;
/* try ethernet interfaces */
n = 0;
d = nil;
f = open(mntpt, OREAD);
if(f >= 0){
n = dirreadall(f, &d);
close(f);
}
for(f = 0; f < n; f++){
if((d[f].mode & DMDIR) == 0 || strncmp(d[f].name, "ether", 5) != 0)
continue;
snprint(buf, sizeof buf, "%s/%s", mntpt, d[f].name);
if(myetheraddr(addr, buf) >= 0){
snprint(eaddr, sizeof(eaddr), "%E", addr);
free(ndbgetvalue(db, &s, "ether", eaddr, "sys", &t));
if(t != nil){
free(d);
goto found;
}
}
}
free(d);
/* nothing else worked, use ip address */
attr = "ip";
t = s.t = myipinfo(db, &attr, 1);
if(t == nil)
return;
found:
/* found in database */
if((tt = ndbfindattr(t, s.t, "sys")) != nil)
mysysname = estrdup(tt->val);
else if((tt = ndbfindattr(t, s.t, "ip")) != nil)
mysysname = estrdup(tt->val);
ndbfree(t);
if(mysysname == nil)
return;
setsys:
/* set /dev/sysname if we now know it */
f = open("/dev/sysname", OWRITE);
if(f >= 0){
write(f, mysysname, strlen(mysysname));
close(f);
}
}
/*
* Set up a list of default networks by looking for
* /net/^*^/clone.
*/
void
netinit(int background)
{
char clone[Maxpath];
Network *np;
if(background){
if(rfork(RFPROC|RFNOTEG|RFMEM|RFNOWAIT) != 0)
return;
qlock(&netlock);
}
/* add the mounted networks to the default list */
for(np = network; np->net != nil; np++){
if(np->considered)
continue;
snprint(clone, sizeof(clone), "%s/%s/clone", mntpt, np->net);
if(access(clone, AEXIST) < 0)
continue;
if(netlist != nil)
last->next = np;
else
netlist = np;
last = np;
np->next = nil;
np->considered = 1;
}
/* find out what our ip addresses are */
readipinterfaces();
/* set the system name if we need to, these days ip is all we have */
ipid();
if(debug)
syslog(0, logfile, "mysysname %s", mysysname?mysysname:"???");
if(background){
qunlock(&netlock);
_exits(0);
}
}
/*
* add networks to the standard list
*/
void
netadd(char *p)
{
Network *np;
char *field[12];
int i, n;
n = getfields(p, field, 12, 1, " ");
for(i = 0; i < n; i++){
for(np = network; np->net != nil; np++){
if(strcmp(field[i], np->net) != 0)
continue;
if(np->considered)
break;
if(netlist != nil)
last->next = np;
else
netlist = np;
last = np;
np->next = nil;
np->considered = 1;
}
}
}
int
lookforproto(Ndbtuple *t, char *proto)
{
for(; t != nil; t = t->entry)
if(strcmp(t->attr, "proto") == 0 && strcmp(t->val, proto) == 0)
return 1;
return 0;
}
/*
* lookup a request. the network "net" means we should pick the
* best network to get there.
*/
int
lookup(Mfile *mf)
{
Network *np;
char *cp;
Ndbtuple *nt, *t;
char reply[Maxreply];
int i, rv, fasttimeout;
/* open up the standard db files */
if(db == nil)
ndbinit();
if(db == nil)
error("can't open mf->network database\n");
if(mf->net == nil)
return 0; /* must have been a genquery */
rv = 0;
if(strcmp(mf->net, "net") == 0){
/*
* go through set of default nets
*/
for(np = mf->nextnet; np != nil && rv == 0; np = np->next){
nt = (*np->lookup)(np, mf->host, mf->serv);
if(nt == nil)
continue;
fasttimeout = np->fasttimeout && !lookforproto(nt, np->net);
for(t = nt; mf->nreply < Nreply && t != nil; t = t->entry){
cp = (*np->trans)(t, np, mf->serv, mf->rem, fasttimeout);
if(cp != nil){
/* avoid duplicates */
for(i = 0; i < mf->nreply; i++)
if(strcmp(mf->reply[i], cp) == 0)
break;
if(i == mf->nreply){
/* save the reply */
mf->replylen[mf->nreply] = strlen(cp);
mf->reply[mf->nreply++] = cp;
rv++;
} else
free(cp);
}
}
ndbfree(nt);
}
mf->nextnet = np;
return rv;
}
/*
* if not /net, we only get one lookup
*/
if(mf->nreply != 0)
return 0;
/*
* look for a specific network
*/
for(np = network; np->net != nil; np++){
if(np->fasttimeout)
continue;
if(strcmp(np->net, mf->net) == 0)
break;
}
if(np->net != nil){
/*
* known network
*/
nt = (*np->lookup)(np, mf->host, mf->serv);
for(t = nt; mf->nreply < Nreply && t != nil; t = t->entry){
cp = (*np->trans)(t, np, mf->serv, mf->rem, 0);
if(cp != nil){
mf->replylen[mf->nreply] = strlen(cp);
mf->reply[mf->nreply++] = cp;
rv++;
}
}
ndbfree(nt);
return rv;
} else {
/*
* not a known network, don't translate host or service
*/
if(mf->serv != nil)
snprint(reply, sizeof(reply), "%s/%s/clone %s!%s",
mntpt, mf->net, mf->host, mf->serv);
else
snprint(reply, sizeof(reply), "%s/%s/clone %s",
mntpt, mf->net, mf->host);
mf->reply[0] = estrdup(reply);
mf->replylen[0] = strlen(reply);
mf->nreply = 1;
return 1;
}
}
/*
* translate an ip service name into a port number. If it's a numeric port
* number, look for restricted access.
*
* the service '*' needs no translation.
*/
char*
ipserv(Network *np, char *name, char *buf, int blen)
{
char *p;
int alpha = 0;
int restr = 0;
Ndbtuple *t, *nt;
Ndbs s;
/* '*' means any service */
if(strcmp(name, "*") == 0){
nstrcpy(buf, name, blen);
return buf;
}
/* see if it's numeric or symbolic */
for(p = name; *p; p++){
if(isdigit(*p))
{}
else if(isalpha(*p) || *p == '-' || *p == '$')
alpha = 1;
else
return nil;
}
t = nil;
p = nil;
if(alpha){
p = ndbgetvalue(db, &s, np->net, name, "port", &t);
if(p == nil)
return nil;
} else {
/* look up only for tcp ports < 1024 to get the restricted
* attribute
*/
if(atoi(name) < 1024 && strcmp(np->net, "tcp") == 0)
p = ndbgetvalue(db, &s, "port", name, "port", &t);
if(p == nil)
p = estrdup(name);
}
if(t){
for(nt = t; nt != nil; nt = nt->entry)
if(strcmp(nt->attr, "restricted") == 0)
restr = 1;
ndbfree(t);
}
snprint(buf, blen, "%s%s", p, restr ? "!r" : "");
free(p);
return buf;
}
Ndbtuple*
myipinfo(Ndb *db, char **list, int n)
{
Ndbtuple *t, *nt;
char ip[64];
Ipifc *ifc;
Iplifc *lifc;
t = nil;
qlock(&ipifclock);
for(ifc = ipifcs; ifc != nil; ifc = ifc->next){
for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){
snprint(ip, sizeof(ip), "%I", lifc->ip);
nt = ndbipinfo(db, "ip", ip, list, n);
t = ndbconcatenate(t, nt);
}
}
qunlock(&ipifclock);
return ndbdedup(t);
}
/*
* reorder according to our interfaces
*/
static Ndbtuple*
ipreorder(Ndbtuple *t)
{
Ndbtuple *nt;
uchar ip[IPaddrlen];
uchar net[IPaddrlen];
uchar tnet[IPaddrlen];
Ipifc *ifc;
Iplifc *lifc;
if(t == nil)
return nil;
qlock(&ipifclock);
for(ifc = ipifcs; ifc != nil; ifc = ifc->next){
for(lifc = ifc->lifc; lifc != nil; lifc = lifc->next){
maskip(lifc->ip, lifc->mask, net);
for(nt = t; nt != nil; nt = nt->entry){
if(strcmp(nt->attr, "ip") != 0)
continue;
if(parseip(ip, nt->val) == -1)
continue;
maskip(ip, lifc->mask, tnet);
if(memcmp(net, tnet, IPaddrlen) == 0){
qunlock(&ipifclock);
return ndbreorder(t, nt);
}
}
}
}
qunlock(&ipifclock);
return t;
}
static Ndbtuple*
ndbline(Ndbtuple *t)
{
Ndbtuple *nt;
for(nt = t; nt != nil; nt = nt->entry){
if(nt->entry == nil)
nt->line = t;
else
nt->line = nt->entry;
}
return t;
}
/*
* lookup an ip destination
*/
static Ndbtuple*
iplookuphost(Network *np, char *host)
{
char *attr, *dnsname;
Ndbtuple *t, *nt;
Ndbs s;
/*
* turn '[ip address]' into just 'ip address'
*/
if(*host == '['){
char tmp[Maxhost], *x;
nstrcpy(tmp, host, sizeof tmp);
host = tmp;
if((x = strchr(++host, ']')) != nil)
*x = 0;
}
/* for dial strings with no host */
if(strcmp(host, "*") == 0)
return ndbline(ndbnew("ip", "*"));
/*
* hack till we go v6 :: = 0.0.0.0
*/
if(strcmp("::", host) == 0)
return ndbline(ndbnew("ip", "*"));
/*
* just accept addresses
*/
attr = ipattr(host);
if(strcmp(attr, "ip") == 0)
return ndbline(ndbnew("ip", host));
/*
* give the domain name server the first opportunity to
* resolve domain names. if that fails try the database.
*/
t = nil;
if(strcmp(attr, "dom") == 0)
t = dnsiplookup(host, &s, np->ipvers);
if(t == nil){
for(nt = ndbsearch(db, &s, attr, host); nt != nil; nt = ndbsnext(&s, attr, host)){
if(ndbfindattr(nt, s.t, "ip") == nil){
ndbfree(nt);
continue;
}
t = ndbconcatenate(t, ndbreorder(nt, s.t));
}
s.t = t;
}
if(t == nil){
if(strcmp(attr, "dom") != 0){
dnsname = ndbgetvalue(db, &s, attr, host, "dom", nil);
if(dnsname != nil){
t = dnsiplookup(dnsname, &s, np->ipvers);
free(dnsname);
}
}
if(t == nil)
t = dnsiplookup(host, &s, np->ipvers);
}
if(t == nil)
return nil;
/*
* reorder the tuple to have the matched line first and
* save that in the request structure.
*/
return ndbreorder(t, s.t);
}
Ndbtuple*
iplookup(Network *np, char *host, char *serv)
{
Ndbtuple *l, *t, *nt;
char ts[Maxservice], *attr;
/*
* start with the service since it's the most likely to fail
* and costs the least
*/
if(serv == nil || ipserv(np, serv, ts, sizeof ts) == nil){
werrstr("can't translate service");
return nil;
}
/*
* '$' means the rest of the name is an attribute that we
* need to search for
*/
werrstr("can't translate address");
if(*host == '$'){
t = nil;
attr = host+1;
l = myipinfo(db, &attr, 1);
for(nt = l; nt != nil; nt = nt->entry){
if(strcmp(nt->attr, attr) == 0)
t = ndbconcatenate(t, iplookuphost(np, nt->val));
}
ndbfree(l);
} else
t = iplookuphost(np, host);
return ipreorder(t);
}
/*
* translate an ip address
*/
char*
iptrans(Ndbtuple *t, Network *np, char *serv, char *rem, int fasttimeout)
{
char ts[Maxservice];
char reply[Maxreply];
char x[Maxservice];
uchar ip[IPaddrlen];
if(strcmp(t->attr, "ip") != 0)
return nil;
if(serv == nil || ipserv(np, serv, ts, sizeof ts) == nil){
werrstr("can't translate service");
return nil;
}
if(rem != nil)
snprint(x, sizeof(x), "!%s", rem);
else
*x = 0;
if(*t->val == '*')
snprint(reply, sizeof(reply), "%s/%s/clone %s%s",
mntpt, np->net, ts, x);
else {
if(parseip(ip, t->val) == -1)
return nil;
if((np->ipvers & confipvers & (isv4(ip) ? V4 : V6)) == 0)
return nil;
snprint(reply, sizeof(reply), "%s/%s/clone %I!%s%s%s",
mntpt, np->net, ip, ts, x, fasttimeout? "!fasttimeout": "");
}
return estrdup(reply);
}
/*
* lookup a telephone number
*/
Ndbtuple*
telcolookup(Network *np, char *host, char *serv)
{
Ndbtuple *t;
Ndbs s;
USED(np, serv);
werrstr("can't translate address");
free(ndbgetvalue(db, &s, "sys", host, "telco", &t));
if(t == nil)
return ndbline(ndbnew("telco", host));
return ndbreorder(t, s.t);
}
/*
* translate a telephone address
*/
char*
telcotrans(Ndbtuple *t, Network *np, char *serv, char *rem, int)
{
char reply[Maxreply];
char x[Maxservice];
if(strcmp(t->attr, "telco") != 0)
return nil;
if(rem != nil)
snprint(x, sizeof(x), "!%s", rem);
else
*x = 0;
if(serv != nil)
snprint(reply, sizeof(reply), "%s/%s/clone %s!%s%s", mntpt, np->net,
t->val, serv, x);
else
snprint(reply, sizeof(reply), "%s/%s/clone %s%s", mntpt, np->net,
t->val, x);
return estrdup(reply);
}
/*
* create a slave process to handle a request to avoid one request blocking
* another. parent returns to job loop.
*/
void
slave(char *host)
{
if(*isslave)
return; /* we're already a slave process */
if(ainc(&active) >= Maxactive){
adec(&active);
return;
}
switch(rfork(RFPROC|RFNOTEG|RFMEM|RFNOWAIT)){
case -1:
adec(&active);
break;
case 0:
*isslave = 1;
if(debug)
syslog(0, logfile, "slave %d", getpid());
procsetname("%s", host);
break;
default:
longjmp(masterjmp, 1);
}
}
static int
mountdns(void)
{
static QLock mountlock;
static int mounted;
char buf[128], *p;
int fd;
if(mounted)
return 0;
qlock(&mountlock);
snprint(buf, sizeof(buf), "%s/dns", mntpt);
if(access(buf, AEXIST) == 0)
goto done;
if(strcmp(mntpt, "/net") == 0)
snprint(buf, sizeof(buf), "/srv/dns");
else {
snprint(buf, sizeof(buf), "/srv/dns%s", mntpt);
while((p = strchr(buf+8, '/')) != nil)
*p = '_';
}
if((fd = open(buf, ORDWR)) < 0){
err:
qunlock(&mountlock);
return -1;
}
if(mount(fd, -1, mntpt, MAFTER, "") < 0){
close(fd);
goto err;
}
done:
mounted = 1;
qunlock(&mountlock);
return 0;
}
static Ndbtuple*
dnsip6lookup(char *mntpt, char *buf, Ndbtuple *t)
{
Ndbtuple *t6, *tt;
t6 = dnsquery(mntpt, buf, "ipv6"); /* lookup AAAA dns RRs */
if (t6 == nil)
return t;
/* convert ipv6 attr to ip */
for (tt = t6; tt != nil; tt = tt->entry)
if (strcmp(tt->attr, "ipv6") == 0)
strcpy(tt->attr, "ip");
/* append t6 list to t list */
return ndbconcatenate(t, t6);
}
/*
* call the dns process and have it try to translate a name
*/
Ndbtuple*
dnsiplookup(char *host, Ndbs *s, int ipvers)
{
char buf[Maxreply];
Ndbtuple *t;
ipvers &= dnsipvers & lookipvers;
if(ipvers == 0){
werrstr("no ip address");
return nil;
}
qunlock(&dblock);
slave(host);
if(*isslave == 0){
qlock(&dblock);
werrstr("too much activity");
return nil;
}
if(mountdns() < 0){
qlock(&dblock);
return nil;
}
if(strcmp(ipattr(host), "ip") == 0)
t = dnsquery(mntpt, host, "ptr");
else {
t = nil;
if(ipvers & V4)
t = dnsquery(mntpt, host, "ip");
if(ipvers & V6)
t = dnsip6lookup(mntpt, host, t);
}
s->t = t;
if(t == nil){
rerrstr(buf, sizeof buf);
if(strstr(buf, "exist") != nil)
werrstr("can't translate address: %s", buf);
else if(strstr(buf, "dns failure") != nil)
werrstr("temporary problem: %s", buf);
}
qlock(&dblock);
return t;
}
int
qmatch(Ndbtuple *t, char **attr, char **val, int n)
{
int i, found;
Ndbtuple *nt;
for(i = 1; i < n; i++){
found = 0;
for(nt = t; nt != nil; nt = nt->entry)
if(strcmp(attr[i], nt->attr) == 0)
if(strcmp(val[i], "*") == 0
|| strcmp(val[i], nt->val) == 0){
found = 1;
break;
}
if(found == 0)
break;
}
return i == n;
}
void
qreply(Mfile *mf, Ndbtuple *t)
{
Ndbtuple *nt;
String *s;
s = s_new();
for(nt = t; mf->nreply < Nreply && nt != nil; nt = nt->entry){
s_append(s, nt->attr);
s_append(s, "=");
s_append(s, nt->val);
if(nt->line != nt->entry){
mf->replylen[mf->nreply] = s_len(s);
mf->reply[mf->nreply++] = estrdup(s_to_c(s));
s_restart(s);
} else
s_append(s, " ");
}
s_free(s);
}
enum
{
Maxattr= 32,
};
/*
* generic query lookup. The query is of one of the following
* forms:
*
* attr1=val1 attr2=val2 attr3=val3 ...
*
* returns the matching tuple
*
* ipinfo attr=val attr1 attr2 attr3 ...
*
* is like ipinfo and returns the attr{1-n}
* associated with the ip address.
*/
char*
genquery(Mfile *mf, char *query)
{
int i, n;
char *p;
char *attr[Maxattr];
char *val[Maxattr];
Ndbtuple *t;
Ndbs s;
n = getfields(query, attr, nelem(attr), 1, " ");
if(n == 0)
return "bad query";
if(strcmp(attr[0], "ipinfo") == 0)
return ipinfoquery(mf, attr, n);
/* parse pairs */
for(i = 0; i < n; i++){
p = strchr(attr[i], '=');
if(p == nil)
return "bad query";
*p++ = 0;
val[i] = p;
}
/* give dns a chance */
if((strcmp(attr[0], "dom") == 0 || strcmp(attr[0], "ip") == 0) && val[0]){
t = dnsiplookup(val[0], &s, lookipvers);
if(t != nil){
if(qmatch(t, attr, val, n)){
qreply(mf, t);
ndbfree(t);
return nil;
}
ndbfree(t);
}
}
/* first pair is always the key. It can't be a '*' */
t = ndbsearch(db, &s, attr[0], val[0]);
/* search is the and of all the pairs */
while(t != nil){
if(qmatch(t, attr, val, n)){
qreply(mf, t);
ndbfree(t);
return nil;
}
ndbfree(t);
t = ndbsnext(&s, attr[0], val[0]);
}
return "no match";
}
/*
* resolve an ip address
*/
static Ndbtuple*
ipresolve(char *attr, char *host)
{
Ndbtuple *t, *nt, **l;
t = iplookup(&network[Ntcp], host, "*");
for(l = &t; *l != nil; ){
nt = *l;
if(strcmp(nt->attr, "ip") != 0){
*l = nt->entry;
nt->entry = nil;
ndbfree(nt);
continue;
}
nstrcpy(nt->attr, attr, sizeof(nt->attr));
l = &nt->entry;
}
return t;
}
char*
ipinfoquery(Mfile *mf, char **list, int n)
{
int i, nresolve;
uchar resolve[Maxattr];
Ndbtuple *t, *nt, **l;
char *attr, *val;
/* skip 'ipinfo' */
list++; n--;
if(n < 1)
return "bad query";
/* get search attribute=value, or assume myip */
attr = *list;
if((val = strchr(attr, '=')) != nil){
*val++ = 0;
list++;
n--;
}else{
attr = nil;
val = nil;
}
if(n < 1)
return "bad query";
/*
* don't let ndbipinfo resolve the addresses, we're
* better at it.
*/
nresolve = 0;
for(i = 0; i < n; i++)
if(*list[i] == '@'){ /* @attr=val ? */
list[i]++;
resolve[i] = 1; /* we'll resolve it */
nresolve++;
} else
resolve[i] = 0;
if(attr == nil)
t = myipinfo(db, list, n);
else
t = ndbipinfo(db, attr, val, list, n);
if(t == nil)
return "no match";
if(nresolve != 0){
for(l = &t; *l != nil;){
nt = *l;
/* already an address? */
if(strcmp(ipattr(nt->val), "ip") == 0){
l = &(*l)->entry;
continue;
}
/* user wants it resolved? */
for(i = 0; i < n; i++)
if(strcmp(list[i], nt->attr) == 0)
break;
if(i >= n || resolve[i] == 0){
l = &(*l)->entry;
continue;
}
/* resolve address and replace entry */
*l = ipresolve(nt->attr, nt->val);
while(*l != nil)
l = &(*l)->entry;
*l = nt->entry;
nt->entry = nil;
ndbfree(nt);
}
t = ndbdedup(t);
}
/* make it all one line */
t = ndbline(t);
qreply(mf, t);
return nil;
}
void*
emalloc(int size)
{
void *x;
x = malloc(size);
if(x == nil)
error("out of memory");
memset(x, 0, size);
return x;
}
char*
estrdup(char *s)
{
int size;
char *p;
size = strlen(s);
p = malloc(size+1);
if(p == nil)
error("out of memory");
memmove(p, s, size);
p[size] = 0;
return p;
}