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/*
* guard service
*/
#include <u.h>
#include <libc.h>
#include <fcall.h>
#include <bio.h>
#include <ndb.h>
#include <authsrv.h>
#include "authcmdlib.h"
enum {
Pinlen = 4,
};
/*
* c -> a client
* a -> c challenge prompt
* c -> a KC'{challenge}
* a -> c OK or NO
*/
void catchalarm(void*, char*);
void getraddr(char*);
char user[ANAMELEN];
char raddr[128];
int debug;
Ndb *db;
void
main(int argc, char *argv[])
{
int n;
long chal;
char *err;
char ukey[DESKEYLEN], resp[32], buf[NETCHLEN];
Ndb *db2;
ARGBEGIN{
case 'd':
debug = 1;
break;
}ARGEND;
db = ndbopen("/lib/ndb/auth");
if(db == 0)
syslog(0, AUTHLOG, "no /lib/ndb/auth");
db2 = ndbopen(0);
if(db2 == 0)
syslog(0, AUTHLOG, "no /lib/ndb/local");
db = ndbcat(db, db2);
werrstr("");
strcpy(raddr, "unknown");
if(argc >= 1)
getraddr(argv[argc-1]);
argv0 = "guard";
srand((getpid()*1103515245)^time(0));
notify(catchalarm);
/*
* read the host and client and get their keys
*/
if(readarg(0, user, sizeof user) < 0)
fail(0);
/*
* challenge-response
*/
chal = lnrand(MAXNETCHAL);
sprint(buf, "challenge: %lud\nresponse: ", chal);
n = strlen(buf) + 1;
if(write(1, buf, n) != n){
if(debug)
syslog(0, AUTHLOG, "g-fail %s@%s: %r sending chal",
user, raddr);
exits("replying to server");
}
alarm(3*60*1000);
werrstr("");
if(readarg(0, resp, sizeof resp) < 0){
if(debug)
syslog(0, AUTHLOG, "g-fail %s@%s: %r reading resp",
user, raddr);
fail(0);
}
alarm(0);
/* remove password login from guard.research.bell-labs.com, sucre, etc. */
// if(!findkey(KEYDB, user, ukey) || !netcheck(ukey, chal, resp))
if(!findkey(NETKEYDB, user, ukey) || !netcheck(ukey, chal, resp))
if((err = secureidcheck(user, resp)) != nil){
print("NO %s", err);
write(1, "NO", 2);
if(debug) {
char *r;
/*
* don't log the entire response, since the first
* Pinlen digits may be the user's secure-id pin.
*/
if (strlen(resp) < Pinlen)
r = strdup("<too short for pin>");
else if (strlen(resp) == Pinlen)
r = strdup("<pin only>");
else
r = smprint("%.*s%s", Pinlen,
"******************", resp + Pinlen);
syslog(0, AUTHLOG,
"g-fail %s@%s: %s: resp %s to chal %lud",
user, raddr, err, r, chal);
free(r);
}
fail(user);
}
write(1, "OK", 2);
if(debug)
syslog(0, AUTHLOG, "g-ok %s@%s", user, raddr);
succeed(user);
exits(0);
}
void
catchalarm(void *x, char *msg)
{
USED(x, msg);
if(debug)
syslog(0, AUTHLOG, "g-timed out %s", raddr);
fail(0);
}
void
getraddr(char *dir)
{
int n, fd;
char *cp;
char file[128];
snprint(file, sizeof(file), "%s/remote", dir);
fd = open(file, OREAD);
if(fd < 0)
return;
n = read(fd, raddr, sizeof(raddr)-1);
close(fd);
if(n <= 0)
return;
raddr[n] = 0;
cp = strchr(raddr, '\n');
if(cp)
*cp = 0;
cp = strchr(raddr, '!');
if(cp)
*cp = 0;
}
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