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 1.4 2002/02/19 20:36:22 epeyton 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 <string.h>
  74 #include <unistd.h>
  75 #include <sys/param.h>
  76 #include <sys/types.h>
  77 #include <netinet/in.h>
  78
  79 #include <rpc/types.h>
  80 #include <rpc/xdr.h>
  81 #include <rpc/auth.h>
  82 #include <rpc/auth_unix.h>
  83
  84 extern bool_t   xdr_opaque_auth();
  85
  86 /*
  87  * Unix authenticator operations vector
  88  */
  89 static void     authunix_nextverf();
  90 static bool_t   authunix_marshal();
  91 static bool_t   authunix_validate();
  92 static bool_t   authunix_refresh();
  93 static void     authunix_destroy();
  94
  95 static struct auth_ops auth_unix_ops = {
  96         authunix_nextverf,
  97         authunix_marshal,
  98         authunix_validate,
  99         authunix_refresh,
 100         authunix_destroy
 101 };
 102
 103 /*
 104  * This struct is pointed to by the ah_private field of an auth_handle.
 105  */
 106 struct audata {
 107         struct opaque_auth      au_origcred;    /* original credentials */
 108         struct opaque_auth      au_shcred;      /* short hand cred */
 109         u_long                  au_shfaults;    /* short hand cache faults */
 110         char                    au_marshed[MAX_AUTH_BYTES];
 111         u_int                   au_mpos;        /* xdr pos at end of marshed */
 112 };
 113 #define AUTH_PRIVATE(auth)      ((struct audata *)auth->ah_private)
 114
 115 static void marshal_new_auth();
 116
 117
 118 /*
 119  * Create a unix style authenticator.
 120  * Returns an auth handle with the given stuff in it.
 121  */
 122 AUTH *
 123 authunix_create(machname, uid, gid, len, aup_gids)
 124         char *machname;
 125         int uid;
 126         int gid;
 127         register int len;
 128         int *aup_gids;
 129 {
 130         struct authunix_parms aup;
 131         char mymem[MAX_AUTH_BYTES];
 132         struct timeval now;
 133         XDR xdrs;
 134         register AUTH *auth;
 135         register struct audata *au;
 136
 137         /*
 138          * Allocate and set up auth handle
 139          */
 140         auth = (AUTH *)mem_alloc(sizeof(*auth));
 141 #ifndef KERNEL
 142         if (auth == NULL) {
 143                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 144                 return (NULL);
 145         }
 146 #endif
 147         au = (struct audata *)mem_alloc(sizeof(*au));
 148 #ifndef KERNEL
 149         if (au == NULL) {
 150                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 151                 return (NULL);
 152         }
 153 #endif
 154         auth->ah_ops = &auth_unix_ops;
 155         auth->ah_private = (caddr_t)au;
 156         auth->ah_verf = au->au_shcred = _null_auth;
 157         au->au_shfaults = 0;
 158
 159         /*
 160          * fill in param struct from the given params
 161          */
 162         (void)gettimeofday(&now,  (struct timezone *)0);
 163         aup.aup_time = now.tv_sec;
 164         aup.aup_machname = machname;
 165         aup.aup_uid = uid;
 166         aup.aup_gid = gid;
 167         aup.aup_len = (u_int)len;
 168         aup.aup_gids = aup_gids;
 169
 170         /*
 171          * Serialize the parameters into origcred
 172          */
 173         xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE);
 174         if (! xdr_authunix_parms(&xdrs, &aup))
 175                 abort();
 176         au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs);
 177         au->au_origcred.oa_flavor = AUTH_UNIX;
 178 #ifdef KERNEL
 179         au->au_origcred.oa_base = mem_alloc((u_int) len);
 180 #else
 181         if ((au->au_origcred.oa_base = mem_alloc((u_int) len)) == NULL) {
 182                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 183                 return (NULL);
 184         }
 185 #endif
 186         bcopy(mymem, au->au_origcred.oa_base, (u_int)len);
 187
 188         /*
 189          * set auth handle to reflect new cred.
 190          */
 191         auth->ah_cred = au->au_origcred;
 192         marshal_new_auth(auth);
 193         return (auth);
 194 }
 195
 196 /*
 197 * Some servers will refuse mounts if the group list is larger
 198 * than it expects (like 8). This allows the application to set
 199 * the maximum size of the group list that will be sent.
 200 */
 201
 202 static int maxgrplist = NGROUPS;
 203
 204 void
 205 set_rpc_maxgrouplist(num)
 206         int num;
 207 {
 208     if (num < NGROUPS)
 209         maxgrplist = num;
 210 }
 211
 212 /*
 213  * Returns an auth handle with parameters determined by doing lots of
 214  * syscalls.
 215  */
 216 AUTH *
 217 authunix_create_default()
 218 {
 219         register int len;
 220         char machname[MAX_MACHINE_NAME + 1];
 221         register int uid;
 222         register int gid;
 223         gid_t gids[NGROUPS];
 224
 225         if (gethostname(machname, MAX_MACHINE_NAME) == -1)
 226                 abort();
 227         machname[MAX_MACHINE_NAME] = 0;
 228         uid = geteuid();
 229         gid = getegid();
 230         if ((len = getgroups(NGROUPS, gids)) < 0)
 231                 abort();
 232         if (len > maxgrplist) {
 233             len = maxgrplist;
 234         }
 235         return (authunix_create(machname, uid, gid, len, (int *)gids));
 236 }
 237
 238 /*
 239  * authunix operations
 240  */
 241
 242 static void
 243 authunix_nextverf(auth)
 244         AUTH *auth;
 245 {
 246         /* no action necessary */
 247 }
 248
 249 static bool_t
 250 authunix_marshal(auth, xdrs)
 251         AUTH *auth;
 252         XDR *xdrs;
 253 {
 254         register struct audata *au = AUTH_PRIVATE(auth);
 255
 256         return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos));
 257 }
 258
 259 static bool_t
 260 authunix_validate(auth, verf)
 261         register AUTH *auth;
 262         struct opaque_auth verf;
 263 {
 264         register struct audata *au;
 265         XDR xdrs;
 266
 267         if (verf.oa_flavor == AUTH_SHORT) {
 268                 au = AUTH_PRIVATE(auth);
 269                 xdrmem_create(&xdrs, verf.oa_base, verf.oa_length, XDR_DECODE);
 270
 271                 if (au->au_shcred.oa_base != NULL) {
 272                         mem_free(au->au_shcred.oa_base,
 273                             au->au_shcred.oa_length);
 274                         au->au_shcred.oa_base = NULL;
 275                 }
 276                 if (xdr_opaque_auth(&xdrs, &au->au_shcred)) {
 277                         auth->ah_cred = au->au_shcred;
 278                 } else {
 279                         xdrs.x_op = XDR_FREE;
 280                         (void)xdr_opaque_auth(&xdrs, &au->au_shcred);
 281                         au->au_shcred.oa_base = NULL;
 282                         auth->ah_cred = au->au_origcred;
 283                 }
 284                 marshal_new_auth(auth);
 285         }
 286         return (TRUE);
 287 }
 288
 289 static bool_t
 290 authunix_refresh(auth)
 291         register AUTH *auth;
 292 {
 293         register struct audata *au = AUTH_PRIVATE(auth);
 294         struct authunix_parms aup;
 295         struct timeval now;
 296         XDR xdrs;
 297         register int stat;
 298
 299         if (auth->ah_cred.oa_base == au->au_origcred.oa_base) {
 300                 /* there is no hope.  Punt */
 301                 return (FALSE);
 302         }
 303         au->au_shfaults ++;
 304
 305         /* first deserialize the creds back into a struct authunix_parms */
 306         aup.aup_machname = NULL;
 307         aup.aup_gids = (int *)NULL;
 308         xdrmem_create(&xdrs, au->au_origcred.oa_base,
 309             au->au_origcred.oa_length, XDR_DECODE);
 310         stat = xdr_authunix_parms(&xdrs, &aup);
 311         if (! stat)
 312                 goto done;
 313
 314         /* update the time and serialize in place */
 315         (void)gettimeofday(&now, (struct timezone *)0);
 316         aup.aup_time = now.tv_sec;
 317         xdrs.x_op = XDR_ENCODE;
 318         XDR_SETPOS(&xdrs, 0);
 319         stat = xdr_authunix_parms(&xdrs, &aup);
 320         if (! stat)
 321                 goto done;
 322         auth->ah_cred = au->au_origcred;
 323         marshal_new_auth(auth);
 324 done:
 325         /* free the struct authunix_parms created by deserializing */
 326         xdrs.x_op = XDR_FREE;
 327         (void)xdr_authunix_parms(&xdrs, &aup);
 328         XDR_DESTROY(&xdrs);
 329         return (stat);
 330 }
 331
 332 static void
 333 authunix_destroy(auth)
 334         register AUTH *auth;
 335 {
 336         register struct audata *au = AUTH_PRIVATE(auth);
 337
 338         mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length);
 339
 340         if (au->au_shcred.oa_base != NULL)
 341                 mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length);
 342
 343         mem_free(auth->ah_private, sizeof(struct audata));
 344
 345         if (auth->ah_verf.oa_base != NULL)
 346                 mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length);
 347
 348         mem_free((caddr_t)auth, sizeof(*auth));
 349 }
 350
 351 /*
 352  * Marshals (pre-serializes) an auth struct.
 353  * sets private data, au_marshed and au_mpos
 354  */
 355 static void
 356 marshal_new_auth(auth)
 357         register AUTH *auth;
 358 {
 359         XDR             xdr_stream;
 360         register XDR    *xdrs = &xdr_stream;
 361         register struct audata *au = AUTH_PRIVATE(auth);
 362
 363         xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE);
 364         if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) ||
 365             (! xdr_opaque_auth(xdrs, &(auth->ah_verf)))) {
 366                 perror("auth_none.c - Fatal marshalling problem");
 367         } else {
 368                 au->au_mpos = XDR_GETPOS(xdrs);
 369         }
 370         XDR_DESTROY(xdrs);
 371 }