freebsd-src/eBones/krb/read_service_key.c
Geoff Rehmet 60643d379b Initial import of eBones.
(Including all changes for FreeBSD - importing the original eBones distribution
would be too complex at this stage, since I don't have access to Piero's 
CVS.)
(If you want to include eBones in your system, don't forget to include
MAKE_EBONES in /etc/make.conf.)
(This stuff is now also suppable from braae.ru.ac.za.)

Bones originally from MIT SIPB.
Original port to FreeBSD 1.x  by Piero Serini.
Moved to FreeBSD 2.0 by Doug Rabson and Geoff Rehmet.
Nice bug fixes from Doug Rabson.
1994-09-30 14:50:09 +00:00

121 lines
3.6 KiB
C

/*
* Copyright 1985, 1986, 1987, 1988 by the Massachusetts Institute
* of Technology.
* For copying and distribution information, please see the file
* <Copyright.MIT>.
*
* from: _service_key.c,v 4.10 90/03/10 19:06:56 jon Exp $
* $Id: read_service_key.c,v 1.2 1994/07/19 19:26:16 g89r4222 Exp $
*/
#ifndef lint
static char *rcsid =
"$Id: read_service_key.c,v 1.2 1994/07/19 19:26:16 g89r4222 Exp $";
#endif /* lint */
#include <krb.h>
#include <stdio.h>
#include <strings.h>
/*
* The private keys for servers on a given host are stored in a
* "srvtab" file (typically "/etc/srvtab"). This routine extracts
* a given server's key from the file.
*
* read_service_key() takes the server's name ("service"), "instance",
* and "realm" and a key version number "kvno", and looks in the given
* "file" for the corresponding entry, and if found, returns the entry's
* key field in "key".
*
* If "instance" contains the string "*", then it will match
* any instance, and the chosen instance will be copied to that
* string. For this reason it is important that the there is enough
* space beyond the "*" to receive the entry.
*
* If "kvno" is 0, it is treated as a wild card and the first
* matching entry regardless of the "vno" field is returned.
*
* This routine returns KSUCCESS on success, otherwise KFAILURE.
*
* The format of each "srvtab" entry is as follows:
*
* Size Variable Field in file
* ---- -------- -------------
* string serv server name
* string inst server instance
* string realm server realm
* 1 byte vno server key version #
* 8 bytes key server's key
* ... ... ...
*/
/*ARGSUSED */
read_service_key(service,instance,realm,kvno,file,key)
char *service; /* Service Name */
char *instance; /* Instance name or "*" */
char *realm; /* Realm */
int kvno; /* Key version number */
char *file; /* Filename */
char *key; /* Pointer to key to be filled in */
{
char serv[SNAME_SZ];
char inst[INST_SZ];
char rlm[REALM_SZ];
unsigned char vno; /* Key version number */
int wcard;
int stab, open();
if ((stab = open(file, 0, 0)) < NULL)
return(KFAILURE);
wcard = (instance[0] == '*') && (instance[1] == '\0');
while(getst(stab,serv,SNAME_SZ) > 0) { /* Read sname */
(void) getst(stab,inst,INST_SZ); /* Instance */
(void) getst(stab,rlm,REALM_SZ); /* Realm */
/* Vers number */
if (read(stab,(char *)&vno,1) != 1) {
close(stab);
return(KFAILURE);
}
/* Key */
if (read(stab,key,8) != 8) {
close(stab);
return(KFAILURE);
}
/* Is this the right service */
if (strcmp(serv,service))
continue;
/* How about instance */
if (!wcard && strcmp(inst,instance))
continue;
if (wcard)
(void) strncpy(instance,inst,INST_SZ);
/* Is this the right realm */
#ifdef ATHENA_COMPAT
/* XXX For backward compatibility: if keyfile says "Athena"
and caller wants "ATHENA.MIT.EDU", call it a match */
if (strcmp(rlm,realm) &&
(strcmp(rlm,"Athena") ||
strcmp(realm,"ATHENA.MIT.EDU")))
continue;
#else /* ! ATHENA_COMPAT */
if (strcmp(rlm,realm))
continue;
#endif /* ATHENA_COMPAT */
/* How about the key version number */
if (kvno && kvno != (int) vno)
continue;
(void) close(stab);
return(KSUCCESS);
}
/* Can't find the requested service */
(void) close(stab);
return(KFAILURE);
}