rpc.subproj/auth_unix.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.1 (the "License").  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License.
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*
  25  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
  26  * unrestricted use provided that this legend is included on all tape
  27  * media and as a part of the software program in whole or part.  Users
  28  * may copy or modify Sun RPC without charge, but are not authorized
  29  * to license or distribute it to anyone else except as part of a product or
  30  * program developed by the user.
  31  *
  32  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  33  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  34  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  35  *
  36  * Sun RPC is provided with no support and without any obligation on the
  37  * part of Sun Microsystems, Inc. to assist in its use, correction,
  38  * modification or enhancement.
  39  *
  40  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  41  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  42  * OR ANY PART THEREOF.
  43  *
  44  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  45  * or profits or other special, indirect and consequential damages, even if
  46  * Sun has been advised of the possibility of such damages.
  47  *
  48  * Sun Microsystems, Inc.
  49  * 2550 Garcia Avenue
  50  * Mountain View, California  94043
  51  */
  52
  53 #if defined(LIBC_SCCS) && !defined(lint)
  54 /*static char *sccsid = "from: @(#)auth_unix.c 1.19 87/08/11 Copyr 1984 Sun Micro";*/
  55 /*static char *sccsid = "from: @(#)auth_unix.c  2.2 88/08/01 4.0 RPCSRC";*/
  56 static char *rcsid = "$Id: auth_unix.c,v 1.3 2001/01/17 19:05:42 majka Exp $";
  57 #endif
  58
  59 /*
  60  * auth_unix.c, Implements UNIX style authentication parameters.
  61  *
  62  * Copyright (C) 1984, Sun Microsystems, Inc.
  63  *
  64  * The system is very weak.  The client uses no encryption for it's
  65  * credentials and only sends null verifiers.  The server sends backs
  66  * null verifiers or optionally a verifier that suggests a new short hand
  67  * for the credentials.
  68  *
  69  */
  70
  71 #include <stdio.h>
  72 #include <stdlib.h>
  73 #include <sys/param.h>
  74
  75 #include <rpc/types.h>
  76 #include <rpc/xdr.h>
  77 #include <rpc/auth.h>
  78 #include <rpc/auth_unix.h>
  79
  80 /*
  81  * Unix authenticator operations vector
  82  */
  83 static void     authunix_nextverf();
  84 static bool_t   authunix_marshal();
  85 static bool_t   authunix_validate();
  86 static bool_t   authunix_refresh();
  87 static void     authunix_destroy();
  88
  89 static struct auth_ops auth_unix_ops = {
  90         authunix_nextverf,
  91         authunix_marshal,
  92         authunix_validate,
  93         authunix_refresh,
  94         authunix_destroy
  95 };
  96
  97 /*
  98  * This struct is pointed to by the ah_private field of an auth_handle.
  99  */
 100 struct audata {
 101         struct opaque_auth      au_origcred;    /* original credentials */
 102         struct opaque_auth      au_shcred;      /* short hand cred */
 103         u_long                  au_shfaults;    /* short hand cache faults */
 104         char                    au_marshed[MAX_AUTH_BYTES];
 105         u_int                   au_mpos;        /* xdr pos at end of marshed */
 106 };
 107 #define AUTH_PRIVATE(auth)      ((struct audata *)auth->ah_private)
 108
 109 static bool_t marshal_new_auth();
 110
 111
 112 /*
 113  * Create a unix style authenticator.
 114  * Returns an auth handle with the given stuff in it.
 115  */
 116 AUTH *
 117 authunix_create(machname, uid, gid, len, aup_gids)
 118         char *machname;
 119         int uid;
 120         int gid;
 121         register int len;
 122         int *aup_gids;
 123 {
 124         struct authunix_parms aup;
 125         char mymem[MAX_AUTH_BYTES];
 126         struct timeval now;
 127         XDR xdrs;
 128         register AUTH *auth;
 129         register struct audata *au;
 130
 131         /*
 132          * Allocate and set up auth handle
 133          */
 134         auth = (AUTH *)mem_alloc(sizeof(*auth));
 135 #ifndef KERNEL
 136         if (auth == NULL) {
 137                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 138                 return (NULL);
 139         }
 140 #endif
 141         au = (struct audata *)mem_alloc(sizeof(*au));
 142 #ifndef KERNEL
 143         if (au == NULL) {
 144                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 145                 return (NULL);
 146         }
 147 #endif
 148         auth->ah_ops = &auth_unix_ops;
 149         auth->ah_private = (caddr_t)au;
 150         auth->ah_verf = au->au_shcred = _null_auth;
 151         au->au_shfaults = 0;
 152
 153         /*
 154          * fill in param struct from the given params
 155          */
 156         (void)gettimeofday(&now,  (struct timezone *)0);
 157         aup.aup_time = now.tv_sec;
 158         aup.aup_machname = machname;
 159         aup.aup_uid = uid;
 160         aup.aup_gid = gid;
 161         aup.aup_len = (u_int)len;
 162         aup.aup_gids = aup_gids;
 163
 164         /*
 165          * Serialize the parameters into origcred
 166          */
 167         xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE);
 168         if (! xdr_authunix_parms(&xdrs, &aup))
 169                 abort();
 170         au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs);
 171         au->au_origcred.oa_flavor = AUTH_UNIX;
 172 #ifdef KERNEL
 173         au->au_origcred.oa_base = mem_alloc((u_int) len);
 174 #else
 175         if ((au->au_origcred.oa_base = mem_alloc((u_int) len)) == NULL) {
 176                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 177                 return (NULL);
 178         }
 179 #endif
 180         bcopy(mymem, au->au_origcred.oa_base, (u_int)len);
 181
 182         /*
 183          * set auth handle to reflect new cred.
 184          */
 185         auth->ah_cred = au->au_origcred;
 186         marshal_new_auth(auth);
 187         return (auth);
 188 }
 189
 190 /*
 191 * Some servers will refuse mounts if the group list is larger
 192 * than it expects (like 8). This allows the application to set
 193 * the maximum size of the group list that will be sent.
 194 */
 195
 196 static maxgrplist = NGROUPS;
 197
 198 set_rpc_maxgrouplist(num)
 199         int num;
 200 {
 201     if (num < NGROUPS)
 202         maxgrplist = num;
 203 }
 204
 205 /*
 206  * Returns an auth handle with parameters determined by doing lots of
 207  * syscalls.
 208  */
 209 AUTH *
 210 authunix_create_default()
 211 {
 212         register int len;
 213         char machname[MAX_MACHINE_NAME + 1];
 214         register int uid;
 215         register int gid;
 216         int gids[NGROUPS];
 217
 218         if (gethostname(machname, MAX_MACHINE_NAME) == -1)
 219                 abort();
 220         machname[MAX_MACHINE_NAME] = 0;
 221         uid = geteuid();
 222         gid = getegid();
 223         if ((len = getgroups(NGROUPS, gids)) < 0)
 224                 abort();
 225         if (len > maxgrplist) {
 226             len = maxgrplist;
 227         }
 228         return (authunix_create(machname, uid, gid, len, gids));
 229 }
 230
 231 /*
 232  * authunix operations
 233  */
 234
 235 static void
 236 authunix_nextverf(auth)
 237         AUTH *auth;
 238 {
 239         /* no action necessary */
 240 }
 241
 242 static bool_t
 243 authunix_marshal(auth, xdrs)
 244         AUTH *auth;
 245         XDR *xdrs;
 246 {
 247         register struct audata *au = AUTH_PRIVATE(auth);
 248
 249         return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos));
 250 }
 251
 252 static bool_t
 253 authunix_validate(auth, verf)
 254         register AUTH *auth;
 255         struct opaque_auth verf;
 256 {
 257         register struct audata *au;
 258         XDR xdrs;
 259
 260         if (verf.oa_flavor == AUTH_SHORT) {
 261                 au = AUTH_PRIVATE(auth);
 262                 xdrmem_create(&xdrs, verf.oa_base, verf.oa_length, XDR_DECODE);
 263
 264                 if (au->au_shcred.oa_base != NULL) {
 265                         mem_free(au->au_shcred.oa_base,
 266                             au->au_shcred.oa_length);
 267                         au->au_shcred.oa_base = NULL;
 268                 }
 269                 if (xdr_opaque_auth(&xdrs, &au->au_shcred)) {
 270                         auth->ah_cred = au->au_shcred;
 271                 } else {
 272                         xdrs.x_op = XDR_FREE;
 273                         (void)xdr_opaque_auth(&xdrs, &au->au_shcred);
 274                         au->au_shcred.oa_base = NULL;
 275                         auth->ah_cred = au->au_origcred;
 276                 }
 277                 marshal_new_auth(auth);
 278         }
 279         return (TRUE);
 280 }
 281
 282 static bool_t
 283 authunix_refresh(auth)
 284         register AUTH *auth;
 285 {
 286         register struct audata *au = AUTH_PRIVATE(auth);
 287         struct authunix_parms aup;
 288         struct timeval now;
 289         XDR xdrs;
 290         register int stat;
 291
 292         if (auth->ah_cred.oa_base == au->au_origcred.oa_base) {
 293                 /* there is no hope.  Punt */
 294                 return (FALSE);
 295         }
 296         au->au_shfaults ++;
 297
 298         /* first deserialize the creds back into a struct authunix_parms */
 299         aup.aup_machname = NULL;
 300         aup.aup_gids = (int *)NULL;
 301         xdrmem_create(&xdrs, au->au_origcred.oa_base,
 302             au->au_origcred.oa_length, XDR_DECODE);
 303         stat = xdr_authunix_parms(&xdrs, &aup);
 304         if (! stat)
 305                 goto done;
 306
 307         /* update the time and serialize in place */
 308         (void)gettimeofday(&now, (struct timezone *)0);
 309         aup.aup_time = now.tv_sec;
 310         xdrs.x_op = XDR_ENCODE;
 311         XDR_SETPOS(&xdrs, 0);
 312         stat = xdr_authunix_parms(&xdrs, &aup);
 313         if (! stat)
 314                 goto done;
 315         auth->ah_cred = au->au_origcred;
 316         marshal_new_auth(auth);
 317 done:
 318         /* free the struct authunix_parms created by deserializing */
 319         xdrs.x_op = XDR_FREE;
 320         (void)xdr_authunix_parms(&xdrs, &aup);
 321         XDR_DESTROY(&xdrs);
 322         return (stat);
 323 }
 324
 325 static void
 326 authunix_destroy(auth)
 327         register AUTH *auth;
 328 {
 329         register struct audata *au = AUTH_PRIVATE(auth);
 330
 331         mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length);
 332
 333         if (au->au_shcred.oa_base != NULL)
 334                 mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length);
 335
 336         mem_free(auth->ah_private, sizeof(struct audata));
 337
 338         if (auth->ah_verf.oa_base != NULL)
 339                 mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length);
 340
 341         mem_free((caddr_t)auth, sizeof(*auth));
 342 }
 343
 344 /*
 345  * Marshals (pre-serializes) an auth struct.
 346  * sets private data, au_marshed and au_mpos
 347  */
 348 static bool_t
 349 marshal_new_auth(auth)
 350         register AUTH *auth;
 351 {
 352         XDR             xdr_stream;
 353         register XDR    *xdrs = &xdr_stream;
 354         register struct audata *au = AUTH_PRIVATE(auth);
 355
 356         xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE);
 357         if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) ||
 358             (! xdr_opaque_auth(xdrs, &(auth->ah_verf)))) {
 359                 perror("auth_none.c - Fatal marshalling problem");
 360         } else {
 361                 au->au_mpos = XDR_GETPOS(xdrs);
 362         }
 363         XDR_DESTROY(xdrs);
 364 }