glibc/sunrpc/key_call.c

368 lines
9.3 KiB
C

/*
* Copyright (c) 1988 by Sun Microsystems, Inc.
*/
/*
* Sun RPC is a product of Sun Microsystems, Inc. and is provided for
* unrestricted use provided that this legend is included on all tape
* media and as a part of the software program in whole or part. Users
* may copy or modify Sun RPC without charge, but are not authorized
* to license or distribute it to anyone else except as part of a product or
* program developed by the user.
*
* SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
* WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
* PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
*
* Sun RPC is provided with no support and without any obligation on the
* part of Sun Microsystems, Inc. to assist in its use, correction,
* modification or enhancement.
*
* SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
* INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
* OR ANY PART THEREOF.
*
* In no event will Sun Microsystems, Inc. be liable for any lost revenue
* or profits or other special, indirect and consequential damages, even if
* Sun has been advised of the possibility of such damages.
*
* Sun Microsystems, Inc.
* 2550 Garcia Avenue
* Mountain View, California 94043
*/
/*
* The original source is from the RPCSRC 4.0 package from Sun Microsystems.
* The Interface to keyserver protocoll 2 was added by
* Thorsten Kukuk <kukuk@vt.uni-paderborn.de>
*/
#include <stdio.h>
#include <errno.h>
#include <signal.h>
#include <unistd.h>
#include <string.h>
#include <rpc/rpc.h>
#include <rpc/auth.h>
#include <sys/wait.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <rpc/key_prot.h>
#define KEY_TIMEOUT 5 /* per-try timeout in seconds */
#define KEY_NRETRY 12 /* number of retries */
#define debug(msg) /* turn off debugging */
extern int _openchild (char *command, FILE **fto, FILE **ffrom);
static int key_call (u_long, xdrproc_t xdr_arg, char *,
xdrproc_t xdr_rslt, char *) internal_function;
static struct timeval trytimeout = {KEY_TIMEOUT, 0};
static struct timeval tottimeout = {KEY_TIMEOUT *KEY_NRETRY, 0};
int
key_setsecret (char *secretkey)
{
keystatus status;
if (!key_call ((u_long) KEY_SET, (xdrproc_t) xdr_keybuf, secretkey,
(xdrproc_t) xdr_keystatus, (char *) &status))
return -1;
if (status != KEY_SUCCESS)
{
debug ("set status is nonzero");
return -1;
}
return 0;
}
/* key_secretkey_is_set() returns 1 if the keyserver has a secret key
* stored for the caller's effective uid; it returns 0 otherwise
*
* N.B.: The KEY_NET_GET key call is undocumented. Applications shouldn't
* be using it, because it allows them to get the user's secret key.
*/
int
key_secretkey_is_set (void)
{
struct key_netstres kres;
memset (&kres, 0, sizeof (kres));
if (key_call ((u_long) KEY_NET_GET, (xdrproc_t) xdr_void, (char *) NULL,
(xdrproc_t) xdr_key_netstres, (char *) &kres) &&
(kres.status == KEY_SUCCESS) &&
(kres.key_netstres_u.knet.st_priv_key[0] != 0))
{
/* avoid leaving secret key in memory */
memset (kres.key_netstres_u.knet.st_priv_key, 0, HEXKEYBYTES);
return 1;
}
return 0;
}
int
key_encryptsession (char *remotename, des_block *deskey)
{
cryptkeyarg arg;
cryptkeyres res;
arg.remotename = remotename;
arg.deskey = *deskey;
if (!key_call ((u_long) KEY_ENCRYPT, (xdrproc_t) xdr_cryptkeyarg,
(char *) &arg, (xdrproc_t) xdr_cryptkeyres, (char *) &res))
return -1;
if (res.status != KEY_SUCCESS)
{
debug ("encrypt status is nonzero");
return -1;
}
*deskey = res.cryptkeyres_u.deskey;
return 0;
}
int
key_decryptsession (char *remotename, des_block *deskey)
{
cryptkeyarg arg;
cryptkeyres res;
arg.remotename = remotename;
arg.deskey = *deskey;
if (!key_call ((u_long) KEY_DECRYPT, (xdrproc_t) xdr_cryptkeyarg,
(char *) &arg, (xdrproc_t) xdr_cryptkeyres, (char *) &res))
return -1;
if (res.status != KEY_SUCCESS)
{
debug ("decrypt status is nonzero");
return -1;
}
*deskey = res.cryptkeyres_u.deskey;
return 0;
}
int
key_encryptsession_pk (char *remotename, netobj *remotekey,
des_block *deskey)
{
cryptkeyarg2 arg;
cryptkeyres res;
arg.remotename = remotename;
arg.remotekey = *remotekey;
arg.deskey = *deskey;
if (!key_call ((u_long) KEY_ENCRYPT_PK, (xdrproc_t) xdr_cryptkeyarg2,
(char *) &arg, (xdrproc_t) xdr_cryptkeyres, (char *) &res))
return -1;
if (res.status != KEY_SUCCESS)
{
debug ("encrypt status is nonzero");
return -1;
}
*deskey = res.cryptkeyres_u.deskey;
return 0;
}
int
key_decryptsession_pk (char *remotename, netobj *remotekey,
des_block *deskey)
{
cryptkeyarg2 arg;
cryptkeyres res;
arg.remotename = remotename;
arg.remotekey = *remotekey;
arg.deskey = *deskey;
if (!key_call ((u_long) KEY_DECRYPT_PK, (xdrproc_t) xdr_cryptkeyarg2,
(char *) &arg, (xdrproc_t) xdr_cryptkeyres, (char *) &res))
return -1;
if (res.status != KEY_SUCCESS)
{
debug ("decrypt status is nonzero");
return -1;
}
*deskey = res.cryptkeyres_u.deskey;
return 0;
}
int
key_gendes (des_block *key)
{
struct sockaddr_in sin;
CLIENT *client;
int socket;
enum clnt_stat stat;
sin.sin_family = AF_INET;
sin.sin_port = 0;
sin.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
bzero (sin.sin_zero, sizeof (sin.sin_zero));
socket = RPC_ANYSOCK;
client = clntudp_bufcreate (&sin, (u_long) KEY_PROG, (u_long) KEY_VERS,
trytimeout, &socket, RPCSMALLMSGSIZE,
RPCSMALLMSGSIZE);
if (client == NULL)
return -1;
stat = clnt_call (client, KEY_GEN, (xdrproc_t) xdr_void, NULL,
(xdrproc_t) xdr_des_block, (caddr_t) key, tottimeout);
clnt_destroy (client);
close (socket);
if (stat != RPC_SUCCESS)
return -1;
return 0;
}
int
key_setnet (struct key_netstarg *arg)
{
keystatus status;
if (!key_call ((u_long) KEY_NET_PUT, (xdrproc_t) xdr_key_netstarg,
(char *) arg,(xdrproc_t) xdr_keystatus, (char *) &status))
return -1;
if (status != KEY_SUCCESS)
{
debug ("key_setnet status is nonzero");
return -1;
}
return 1;
}
int
key_get_conv (char *pkey, des_block *deskey)
{
cryptkeyres res;
if (!key_call ((u_long) KEY_GET_CONV, (xdrproc_t) xdr_keybuf, pkey,
(xdrproc_t) xdr_cryptkeyres, (char *) &res))
return -1;
if (res.status != KEY_SUCCESS)
{
debug ("get_conv status is nonzero");
return -1;
}
*deskey = res.cryptkeyres_u.deskey;
return 0;
}
/*
* Hack to allow the keyserver to use AUTH_DES (for authenticated
* NIS+ calls, for example). The only functions that get called
* are key_encryptsession_pk, key_decryptsession_pk, and key_gendes.
*
* The approach is to have the keyserver fill in pointers to local
* implementations of these functions, and to call those in key_call().
*/
cryptkeyres *(*__key_encryptsession_pk_LOCAL) (uid_t, char *) = 0;
cryptkeyres *(*__key_decryptsession_pk_LOCAL) (uid_t, char *) = 0;
des_block *(*__key_gendes_LOCAL) (uid_t, char *) = 0;
static int
internal_function
key_call (u_long proc, xdrproc_t xdr_arg, char *arg,
xdrproc_t xdr_rslt, char *rslt)
{
XDR xdrargs;
XDR xdrrslt;
FILE *fargs;
FILE *frslt;
sigset_t oldmask, mask;
union wait status;
int pid;
int success;
uid_t ruid;
uid_t euid;
static char MESSENGER[] = "/usr/etc/keyenvoy";
if (proc == KEY_ENCRYPT_PK && __key_encryptsession_pk_LOCAL)
{
cryptkeyres *res;
res = (*__key_encryptsession_pk_LOCAL) (geteuid (), arg);
*(cryptkeyres *) rslt = *res;
return 1;
}
else if (proc == KEY_DECRYPT_PK && __key_decryptsession_pk_LOCAL)
{
cryptkeyres *res;
res = (*__key_decryptsession_pk_LOCAL) (geteuid (), arg);
*(cryptkeyres *) rslt = *res;
return 1;
}
else if (proc == KEY_GEN && __key_gendes_LOCAL)
{
des_block *res;
res = (*__key_gendes_LOCAL) (geteuid (), 0);
*(des_block *) rslt = *res;
return 1;
}
success = 1;
sigemptyset (&mask);
sigaddset (&mask, SIGCHLD);
sigprocmask (SIG_BLOCK, &mask, &oldmask);
/*
* We are going to exec a set-uid program which makes our effective uid
* zero, and authenticates us with our real uid. We need to make the
* effective uid be the real uid for the setuid program, and
* the real uid be the effective uid so that we can change things back.
*/
euid = geteuid ();
ruid = getuid ();
setreuid (euid, ruid);
pid = _openchild (MESSENGER, &fargs, &frslt);
setreuid (ruid, euid);
if (pid < 0)
{
debug ("open_streams");
sigprocmask(SIG_SETMASK, &oldmask, NULL);
return (0);
}
xdrstdio_create (&xdrargs, fargs, XDR_ENCODE);
xdrstdio_create (&xdrrslt, frslt, XDR_DECODE);
if (!xdr_u_long (&xdrargs, &proc) || !(*xdr_arg) (&xdrargs, arg))
{
debug ("xdr args");
success = 0;
}
fclose (fargs);
if (success && !(*xdr_rslt) (&xdrrslt, rslt))
{
debug ("xdr rslt");
success = 0;
}
fclose(frslt);
wait_again:
if (wait4(pid, &status, 0, NULL) < 0)
{
if (errno == EINTR)
goto wait_again;
debug("wait4");
if (errno == ECHILD || errno == ESRCH)
perror("wait");
else
success = 0;
}
else
if (status.w_retcode)
{
debug("wait4 1");
success = 0;
}
sigprocmask(SIG_SETMASK, &oldmask, NULL);
return (success);
}