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 #ifdef __LP64__
 110         uint32_t                        au_shfaults;    /* short hand cache faults */
 111 #else
 112         u_long                  au_shfaults;    /* short hand cache faults */
 113 #endif
 114         char                    au_marshed[MAX_AUTH_BYTES];
 115         u_int                   au_mpos;        /* xdr pos at end of marshed */
 116 };
 117 #define AUTH_PRIVATE(auth)      ((struct audata *)auth->ah_private)
 118
 119 static void marshal_new_auth();
 120
 121
 122 /*
 123  * Create a unix style authenticator.
 124  * Returns an auth handle with the given stuff in it.
 125  */
 126 AUTH *
 127 authunix_create(machname, uid, gid, len, aup_gids)
 128         char *machname;
 129         int uid;
 130         int gid;
 131         register int len;
 132         int *aup_gids;
 133 {
 134         struct authunix_parms aup;
 135         char mymem[MAX_AUTH_BYTES];
 136         struct timeval now;
 137         XDR xdrs;
 138         register AUTH *auth;
 139         register struct audata *au;
 140
 141         /*
 142          * Allocate and set up auth handle
 143          */
 144         auth = (AUTH *)mem_alloc(sizeof(*auth));
 145 #ifndef KERNEL
 146         if (auth == NULL) {
 147                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 148                 return (NULL);
 149         }
 150 #endif
 151         au = (struct audata *)mem_alloc(sizeof(*au));
 152 #ifndef KERNEL
 153         if (au == NULL) {
 154                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 155                 return (NULL);
 156         }
 157 #endif
 158         auth->ah_ops = &auth_unix_ops;
 159         auth->ah_private = (caddr_t)au;
 160         auth->ah_verf = au->au_shcred = _null_auth;
 161         au->au_shfaults = 0;
 162
 163         /*
 164          * fill in param struct from the given params
 165          */
 166         (void)gettimeofday(&now,  (struct timezone *)0);
 167         aup.aup_time = now.tv_sec;
 168         aup.aup_machname = machname;
 169         aup.aup_uid = uid;
 170         aup.aup_gid = gid;
 171         aup.aup_len = (u_int)len;
 172         aup.aup_gids = aup_gids;
 173
 174         /*
 175          * Serialize the parameters into origcred
 176          */
 177         xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE);
 178         if (! xdr_authunix_parms(&xdrs, &aup))
 179                 abort();
 180         au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs);
 181         au->au_origcred.oa_flavor = AUTH_UNIX;
 182 #ifdef KERNEL
 183         au->au_origcred.oa_base = mem_alloc((u_int) len);
 184 #else
 185         if ((au->au_origcred.oa_base = mem_alloc((u_int) len)) == NULL) {
 186                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 187                 return (NULL);
 188         }
 189 #endif
 190         bcopy(mymem, au->au_origcred.oa_base, (u_int)len);
 191
 192         /*
 193          * set auth handle to reflect new cred.
 194          */
 195         auth->ah_cred = au->au_origcred;
 196         marshal_new_auth(auth);
 197         return (auth);
 198 }
 199
 200 /*
 201 * Some servers will refuse mounts if the group list is larger
 202 * than it expects (like 8). This allows the application to set
 203 * the maximum size of the group list that will be sent.
 204 */
 205
 206 static int maxgrplist = NGROUPS;
 207
 208 void
 209 set_rpc_maxgrouplist(num)
 210         int num;
 211 {
 212     if (num < NGROUPS)
 213         maxgrplist = num;
 214 }
 215
 216 /*
 217  * Returns an auth handle with parameters determined by doing lots of
 218  * syscalls.
 219  */
 220 AUTH *
 221 authunix_create_default()
 222 {
 223         register int len;
 224         char machname[MAX_MACHINE_NAME + 1];
 225         register int uid;
 226         register int gid;
 227         gid_t gids[NGROUPS];
 228
 229         if (gethostname(machname, MAX_MACHINE_NAME) == -1)
 230                 abort();
 231         machname[MAX_MACHINE_NAME] = 0;
 232         uid = geteuid();
 233         gid = getegid();
 234         if ((len = getgroups(NGROUPS, gids)) < 0)
 235                 abort();
 236         if (len > maxgrplist) {
 237             len = maxgrplist;
 238         }
 239         return (authunix_create(machname, uid, gid, len, (int *)gids));
 240 }
 241
 242 /*
 243  * authunix operations
 244  */
 245
 246 static void
 247 authunix_nextverf(auth)
 248         AUTH *auth;
 249 {
 250         /* no action necessary */
 251 }
 252
 253 static bool_t
 254 authunix_marshal(auth, xdrs)
 255         AUTH *auth;
 256         XDR *xdrs;
 257 {
 258         register struct audata *au = AUTH_PRIVATE(auth);
 259
 260         return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos));
 261 }
 262
 263 static bool_t
 264 authunix_validate(auth, verf)
 265         register AUTH *auth;
 266         struct opaque_auth verf;
 267 {
 268         register struct audata *au;
 269         XDR xdrs;
 270
 271         if (verf.oa_flavor == AUTH_SHORT) {
 272                 au = AUTH_PRIVATE(auth);
 273                 xdrmem_create(&xdrs, verf.oa_base, verf.oa_length, XDR_DECODE);
 274
 275                 if (au->au_shcred.oa_base != NULL) {
 276                         mem_free(au->au_shcred.oa_base,
 277                             au->au_shcred.oa_length);
 278                         au->au_shcred.oa_base = NULL;
 279                 }
 280                 if (xdr_opaque_auth(&xdrs, &au->au_shcred)) {
 281                         auth->ah_cred = au->au_shcred;
 282                 } else {
 283                         xdrs.x_op = XDR_FREE;
 284                         (void)xdr_opaque_auth(&xdrs, &au->au_shcred);
 285                         au->au_shcred.oa_base = NULL;
 286                         auth->ah_cred = au->au_origcred;
 287                 }
 288                 marshal_new_auth(auth);
 289         }
 290         return (TRUE);
 291 }
 292
 293 static bool_t
 294 authunix_refresh(auth)
 295         register AUTH *auth;
 296 {
 297         register struct audata *au = AUTH_PRIVATE(auth);
 298         struct authunix_parms aup;
 299         struct timeval now;
 300         XDR xdrs;
 301         register int stat;
 302
 303         if (auth->ah_cred.oa_base == au->au_origcred.oa_base) {
 304                 /* there is no hope.  Punt */
 305                 return (FALSE);
 306         }
 307         au->au_shfaults ++;
 308
 309         /* first deserialize the creds back into a struct authunix_parms */
 310         aup.aup_machname = NULL;
 311         aup.aup_gids = (int *)NULL;
 312         xdrmem_create(&xdrs, au->au_origcred.oa_base,
 313             au->au_origcred.oa_length, XDR_DECODE);
 314         stat = xdr_authunix_parms(&xdrs, &aup);
 315         if (! stat)
 316                 goto done;
 317
 318         /* update the time and serialize in place */
 319         (void)gettimeofday(&now, (struct timezone *)0);
 320         aup.aup_time = now.tv_sec;
 321         xdrs.x_op = XDR_ENCODE;
 322         XDR_SETPOS(&xdrs, 0);
 323         stat = xdr_authunix_parms(&xdrs, &aup);
 324         if (! stat)
 325                 goto done;
 326         auth->ah_cred = au->au_origcred;
 327         marshal_new_auth(auth);
 328 done:
 329         /* free the struct authunix_parms created by deserializing */
 330         xdrs.x_op = XDR_FREE;
 331         (void)xdr_authunix_parms(&xdrs, &aup);
 332         XDR_DESTROY(&xdrs);
 333         return (stat);
 334 }
 335
 336 static void
 337 authunix_destroy(auth)
 338         register AUTH *auth;
 339 {
 340         register struct audata *au = AUTH_PRIVATE(auth);
 341
 342         mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length);
 343
 344         if (au->au_shcred.oa_base != NULL)
 345                 mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length);
 346
 347         mem_free(auth->ah_private, sizeof(struct audata));
 348
 349         if (auth->ah_verf.oa_base != NULL)
 350                 mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length);
 351
 352         mem_free((caddr_t)auth, sizeof(*auth));
 353 }
 354
 355 /*
 356  * Marshals (pre-serializes) an auth struct.
 357  * sets private data, au_marshed and au_mpos
 358  */
 359 static void
 360 marshal_new_auth(auth)
 361         register AUTH *auth;
 362 {
 363         XDR             xdr_stream;
 364         register XDR    *xdrs = &xdr_stream;
 365         register struct audata *au = AUTH_PRIVATE(auth);
 366
 367         xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE);
 368         if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) ||
 369             (! xdr_opaque_auth(xdrs, &(auth->ah_verf)))) {
 370                 perror("auth_none.c - Fatal marshalling problem");
 371         } else {
 372                 au->au_mpos = XDR_GETPOS(xdrs);
 373         }
 374         XDR_DESTROY(xdrs);
 375 }