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                 mem_free(auth, sizeof(*auth));
 155                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 156                 return (NULL);
 157         }
 158 #endif
 159         auth->ah_ops = &auth_unix_ops;
 160         auth->ah_private = (caddr_t)au;
 161         auth->ah_verf = au->au_shcred = _null_auth;
 162         au->au_shfaults = 0;
 163
 164         /*
 165          * fill in param struct from the given params
 166          */
 167         (void)gettimeofday(&now,  (struct timezone *)0);
 168         aup.aup_time = now.tv_sec;
 169         aup.aup_machname = machname;
 170         aup.aup_uid = uid;
 171         aup.aup_gid = gid;
 172         aup.aup_len = (u_int)len;
 173         aup.aup_gids = aup_gids;
 174
 175         /*
 176          * Serialize the parameters into origcred
 177          */
 178         xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE);
 179         if (! xdr_authunix_parms(&xdrs, &aup))
 180                 abort();
 181         au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs);
 182         au->au_origcred.oa_flavor = AUTH_UNIX;
 183 #ifdef KERNEL
 184         au->au_origcred.oa_base = mem_alloc((u_int) len);
 185 #else
 186         if ((au->au_origcred.oa_base = mem_alloc((u_int) len)) == NULL) {
 187                 mem_free(auth, sizeof(*auth));
 188                 mem_free(au, sizeof(*au));
 189                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 190                 return (NULL);
 191         }
 192 #endif
 193         bcopy(mymem, au->au_origcred.oa_base, (u_int)len);
 194
 195         /*
 196          * set auth handle to reflect new cred.
 197          */
 198         auth->ah_cred = au->au_origcred;
 199         marshal_new_auth(auth);
 200         return (auth);
 201 }
 202
 203 /*
 204 * Some servers will refuse mounts if the group list is larger
 205 * than it expects (like 8). This allows the application to set
 206 * the maximum size of the group list that will be sent.
 207 */
 208
 209 static int maxgrplist = NGROUPS;
 210
 211 void
 212 set_rpc_maxgrouplist(num)
 213         int num;
 214 {
 215     if (num < NGROUPS)
 216         maxgrplist = num;
 217 }
 218
 219 /*
 220  * Returns an auth handle with parameters determined by doing lots of
 221  * syscalls.
 222  */
 223 AUTH *
 224 authunix_create_default()
 225 {
 226         register int len;
 227         char machname[MAX_MACHINE_NAME + 1];
 228         register int uid;
 229         register int gid;
 230         gid_t gids[NGROUPS];
 231
 232         if (gethostname(machname, MAX_MACHINE_NAME) == -1)
 233                 abort();
 234         machname[MAX_MACHINE_NAME] = 0;
 235         uid = geteuid();
 236         gid = getegid();
 237         if ((len = getgroups(NGROUPS, gids)) < 0)
 238                 abort();
 239         if (len > maxgrplist) {
 240             len = maxgrplist;
 241         }
 242         return (authunix_create(machname, uid, gid, len, (int *)gids));
 243 }
 244
 245 /*
 246  * authunix operations
 247  */
 248
 249 static void
 250 authunix_nextverf(auth)
 251         AUTH *auth;
 252 {
 253         /* no action necessary */
 254 }
 255
 256 static bool_t
 257 authunix_marshal(auth, xdrs)
 258         AUTH *auth;
 259         XDR *xdrs;
 260 {
 261         register struct audata *au = AUTH_PRIVATE(auth);
 262
 263         return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos));
 264 }
 265
 266 static bool_t
 267 authunix_validate(auth, verf)
 268         register AUTH *auth;
 269         struct opaque_auth verf;
 270 {
 271         register struct audata *au;
 272         XDR xdrs;
 273
 274         if (verf.oa_flavor == AUTH_SHORT) {
 275                 au = AUTH_PRIVATE(auth);
 276                 xdrmem_create(&xdrs, verf.oa_base, verf.oa_length, XDR_DECODE);
 277
 278                 if (au->au_shcred.oa_base != NULL) {
 279                         mem_free(au->au_shcred.oa_base,
 280                             au->au_shcred.oa_length);
 281                         au->au_shcred.oa_base = NULL;
 282                 }
 283                 if (xdr_opaque_auth(&xdrs, &au->au_shcred)) {
 284                         auth->ah_cred = au->au_shcred;
 285                 } else {
 286                         xdrs.x_op = XDR_FREE;
 287                         (void)xdr_opaque_auth(&xdrs, &au->au_shcred);
 288                         au->au_shcred.oa_base = NULL;
 289                         auth->ah_cred = au->au_origcred;
 290                 }
 291                 marshal_new_auth(auth);
 292         }
 293         return (TRUE);
 294 }
 295
 296 static bool_t
 297 authunix_refresh(auth)
 298         register AUTH *auth;
 299 {
 300         register struct audata *au = AUTH_PRIVATE(auth);
 301         struct authunix_parms aup;
 302         struct timeval now;
 303         XDR xdrs;
 304         register int stat;
 305
 306         if (auth->ah_cred.oa_base == au->au_origcred.oa_base) {
 307                 /* there is no hope.  Punt */
 308                 return (FALSE);
 309         }
 310         au->au_shfaults ++;
 311
 312         /* first deserialize the creds back into a struct authunix_parms */
 313         aup.aup_machname = NULL;
 314         aup.aup_gids = (int *)NULL;
 315         xdrmem_create(&xdrs, au->au_origcred.oa_base,
 316             au->au_origcred.oa_length, XDR_DECODE);
 317         stat = xdr_authunix_parms(&xdrs, &aup);
 318         if (! stat)
 319                 goto done;
 320
 321         /* update the time and serialize in place */
 322         (void)gettimeofday(&now, (struct timezone *)0);
 323         aup.aup_time = now.tv_sec;
 324         xdrs.x_op = XDR_ENCODE;
 325         XDR_SETPOS(&xdrs, 0);
 326         stat = xdr_authunix_parms(&xdrs, &aup);
 327         if (! stat)
 328                 goto done;
 329         auth->ah_cred = au->au_origcred;
 330         marshal_new_auth(auth);
 331 done:
 332         /* free the struct authunix_parms created by deserializing */
 333         xdrs.x_op = XDR_FREE;
 334         (void)xdr_authunix_parms(&xdrs, &aup);
 335         XDR_DESTROY(&xdrs);
 336         return (stat);
 337 }
 338
 339 static void
 340 authunix_destroy(auth)
 341         register AUTH *auth;
 342 {
 343         register struct audata *au = AUTH_PRIVATE(auth);
 344
 345         mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length);
 346
 347         if (au->au_shcred.oa_base != NULL)
 348                 mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length);
 349
 350         mem_free(auth->ah_private, sizeof(struct audata));
 351
 352         if (auth->ah_verf.oa_base != NULL)
 353                 mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length);
 354
 355         mem_free((caddr_t)auth, sizeof(*auth));
 356 }
 357
 358 /*
 359  * Marshals (pre-serializes) an auth struct.
 360  * sets private data, au_marshed and au_mpos
 361  */
 362 static void
 363 marshal_new_auth(auth)
 364         register AUTH *auth;
 365 {
 366         XDR             xdr_stream;
 367         register XDR    *xdrs = &xdr_stream;
 368         register struct audata *au = AUTH_PRIVATE(auth);
 369
 370         xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE);
 371         if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) ||
 372             (! xdr_opaque_auth(xdrs, &(auth->ah_verf)))) {
 373                 perror("auth_none.c - Fatal marshalling problem");
 374         } else {
 375                 au->au_mpos = XDR_GETPOS(xdrs);
 376         }
 377         XDR_DESTROY(xdrs);
 378 }