rpc.subproj/auth_unix.c

   1 /*
   2  * Copyright (c) 1999-2018 Apple 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 "libinfo_common.h"
  72
  73 #include <stdio.h>
  74 #include <stdlib.h>
  75 #include <string.h>
  76 #include <unistd.h>
  77 #include <sys/param.h>
  78 #include <sys/types.h>
  79 #include <netinet/in.h>
  80
  81 #include <rpc/types.h>
  82 #include <rpc/xdr.h>
  83 #include <rpc/auth.h>
  84 #include <rpc/auth_unix.h>
  85
  86 extern bool_t   xdr_opaque_auth();
  87
  88 /*
  89  * Unix authenticator operations vector
  90  */
  91 static void     authunix_nextverf();
  92 static bool_t   authunix_marshal();
  93 static bool_t   authunix_validate();
  94 static bool_t   authunix_refresh();
  95 static void     authunix_destroy();
  96
  97 static struct auth_ops auth_unix_ops = {
  98         authunix_nextverf,
  99         authunix_marshal,
 100         authunix_validate,
 101         authunix_refresh,
 102         authunix_destroy
 103 };
 104
 105 /*
 106  * This struct is pointed to by the ah_private field of an auth_handle.
 107  */
 108 struct audata {
 109         struct opaque_auth      au_origcred;    /* original credentials */
 110         struct opaque_auth      au_shcred;      /* short hand cred */
 111 #ifdef __LP64__
 112         uint32_t                        au_shfaults;    /* short hand cache faults */
 113 #else
 114         u_long                  au_shfaults;    /* short hand cache faults */
 115 #endif
 116         char                    au_marshed[MAX_AUTH_BYTES];
 117         u_int                   au_mpos;        /* xdr pos at end of marshed */
 118 };
 119 #define AUTH_PRIVATE(auth)      ((struct audata *)auth->ah_private)
 120
 121 static void marshal_new_auth();
 122
 123
 124 /*
 125  * Create a unix style authenticator.
 126  * Returns an auth handle with the given stuff in it.
 127  */
 128 LIBINFO_EXPORT
 129 AUTH *
 130 authunix_create(machname, uid, gid, len, aup_gids)
 131         char *machname;
 132         int uid;
 133         int gid;
 134         register int len;
 135         int *aup_gids;
 136 {
 137         struct authunix_parms aup;
 138         char mymem[MAX_AUTH_BYTES];
 139         struct timeval now;
 140         XDR xdrs;
 141         register AUTH *auth;
 142         register struct audata *au;
 143
 144         /*
 145          * Allocate and set up auth handle
 146          */
 147         auth = (AUTH *)mem_alloc(sizeof(*auth));
 148 #ifndef KERNEL
 149         if (auth == NULL) {
 150                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 151                 return (NULL);
 152         }
 153 #endif
 154         au = (struct audata *)mem_alloc(sizeof(*au));
 155 #ifndef KERNEL
 156         if (au == NULL) {
 157                 mem_free(auth, sizeof(*auth));
 158                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 159                 return (NULL);
 160         }
 161 #endif
 162         auth->ah_ops = &auth_unix_ops;
 163         auth->ah_private = (caddr_t)au;
 164         auth->ah_verf = au->au_shcred = _null_auth;
 165         au->au_shfaults = 0;
 166
 167         /*
 168          * fill in param struct from the given params
 169          */
 170         (void)gettimeofday(&now,  (struct timezone *)0);
 171         aup.aup_time = now.tv_sec;
 172         aup.aup_machname = machname;
 173         aup.aup_uid = uid;
 174         aup.aup_gid = gid;
 175         aup.aup_len = (u_int)len;
 176         aup.aup_gids = aup_gids;
 177
 178         /*
 179          * Serialize the parameters into origcred
 180          */
 181         xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE);
 182         if (! xdr_authunix_parms(&xdrs, &aup))
 183                 abort();
 184         au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs);
 185         au->au_origcred.oa_flavor = AUTH_UNIX;
 186 #ifdef KERNEL
 187         au->au_origcred.oa_base = mem_alloc((u_int) len);
 188 #else
 189         if ((au->au_origcred.oa_base = mem_alloc((u_int) len)) == NULL) {
 190                 mem_free(auth, sizeof(*auth));
 191                 mem_free(au, sizeof(*au));
 192                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 193                 return (NULL);
 194         }
 195 #endif
 196         bcopy(mymem, au->au_origcred.oa_base, (u_int)len);
 197
 198         /*
 199          * set auth handle to reflect new cred.
 200          */
 201         auth->ah_cred = au->au_origcred;
 202         marshal_new_auth(auth);
 203         return (auth);
 204 }
 205
 206 /*
 207 * Some servers will refuse mounts if the group list is larger
 208 * than it expects (like 8). This allows the application to set
 209 * the maximum size of the group list that will be sent.
 210 */
 211
 212 static int maxgrplist = NGROUPS;
 213
 214 void
 215 set_rpc_maxgrouplist(num)
 216         int num;
 217 {
 218     if (num < NGROUPS)
 219         maxgrplist = num;
 220 }
 221
 222 /*
 223  * Returns an auth handle with parameters determined by doing lots of
 224  * syscalls.
 225  */
 226 LIBINFO_EXPORT
 227 AUTH *
 228 authunix_create_default()
 229 {
 230         register int len;
 231         char machname[MAX_MACHINE_NAME + 1];
 232         register int uid;
 233         register int gid;
 234         gid_t gids[NGROUPS];
 235
 236         if (gethostname(machname, MAX_MACHINE_NAME) == -1)
 237                 abort();
 238         machname[MAX_MACHINE_NAME] = 0;
 239         uid = geteuid();
 240         gid = getegid();
 241         if ((len = getgroups(NGROUPS, gids)) < 0)
 242                 abort();
 243         if (len > maxgrplist) {
 244             len = maxgrplist;
 245         }
 246         return (authunix_create(machname, uid, gid, len, (int *)gids));
 247 }
 248
 249 /*
 250  * authunix operations
 251  */
 252
 253 static void
 254 authunix_nextverf(auth)
 255         AUTH *auth;
 256 {
 257         /* no action necessary */
 258 }
 259
 260 static bool_t
 261 authunix_marshal(auth, xdrs)
 262         AUTH *auth;
 263         XDR *xdrs;
 264 {
 265         register struct audata *au = AUTH_PRIVATE(auth);
 266
 267         return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos));
 268 }
 269
 270 static bool_t
 271 authunix_validate(auth, verf)
 272         register AUTH *auth;
 273         struct opaque_auth verf;
 274 {
 275         register struct audata *au;
 276         XDR xdrs;
 277
 278         if (verf.oa_flavor == AUTH_SHORT) {
 279                 au = AUTH_PRIVATE(auth);
 280                 xdrmem_create(&xdrs, verf.oa_base, verf.oa_length, XDR_DECODE);
 281
 282                 if (au->au_shcred.oa_base != NULL) {
 283                         mem_free(au->au_shcred.oa_base,
 284                             au->au_shcred.oa_length);
 285                         au->au_shcred.oa_base = NULL;
 286                 }
 287                 if (xdr_opaque_auth(&xdrs, &au->au_shcred)) {
 288                         auth->ah_cred = au->au_shcred;
 289                 } else {
 290                         xdrs.x_op = XDR_FREE;
 291                         (void)xdr_opaque_auth(&xdrs, &au->au_shcred);
 292                         au->au_shcred.oa_base = NULL;
 293                         auth->ah_cred = au->au_origcred;
 294                 }
 295                 marshal_new_auth(auth);
 296         }
 297         return (TRUE);
 298 }
 299
 300 static bool_t
 301 authunix_refresh(auth)
 302         register AUTH *auth;
 303 {
 304         register struct audata *au = AUTH_PRIVATE(auth);
 305         struct authunix_parms aup;
 306         struct timeval now;
 307         XDR xdrs;
 308         register int stat;
 309
 310         if (auth->ah_cred.oa_base == au->au_origcred.oa_base) {
 311                 /* there is no hope.  Punt */
 312                 return (FALSE);
 313         }
 314         au->au_shfaults ++;
 315
 316         /* first deserialize the creds back into a struct authunix_parms */
 317         aup.aup_machname = NULL;
 318         aup.aup_gids = (int *)NULL;
 319         xdrmem_create(&xdrs, au->au_origcred.oa_base,
 320             au->au_origcred.oa_length, XDR_DECODE);
 321         stat = xdr_authunix_parms(&xdrs, &aup);
 322         if (! stat)
 323                 goto done;
 324
 325         /* update the time and serialize in place */
 326         (void)gettimeofday(&now, (struct timezone *)0);
 327         aup.aup_time = now.tv_sec;
 328         xdrs.x_op = XDR_ENCODE;
 329         XDR_SETPOS(&xdrs, 0);
 330         stat = xdr_authunix_parms(&xdrs, &aup);
 331         if (! stat)
 332                 goto done;
 333         auth->ah_cred = au->au_origcred;
 334         marshal_new_auth(auth);
 335 done:
 336         /* free the struct authunix_parms created by deserializing */
 337         xdrs.x_op = XDR_FREE;
 338         (void)xdr_authunix_parms(&xdrs, &aup);
 339         XDR_DESTROY(&xdrs);
 340         return (stat);
 341 }
 342
 343 static void
 344 authunix_destroy(auth)
 345         register AUTH *auth;
 346 {
 347         register struct audata *au = AUTH_PRIVATE(auth);
 348
 349         mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length);
 350
 351         if (au->au_shcred.oa_base != NULL)
 352                 mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length);
 353
 354         mem_free(auth->ah_private, sizeof(struct audata));
 355
 356         if (auth->ah_verf.oa_base != NULL)
 357                 mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length);
 358
 359         mem_free((caddr_t)auth, sizeof(*auth));
 360 }
 361
 362 /*
 363  * Marshals (pre-serializes) an auth struct.
 364  * sets private data, au_marshed and au_mpos
 365  */
 366 static void
 367 marshal_new_auth(auth)
 368         register AUTH *auth;
 369 {
 370         XDR             xdr_stream;
 371         register XDR    *xdrs = &xdr_stream;
 372         register struct audata *au = AUTH_PRIVATE(auth);
 373
 374         xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE);
 375         if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) ||
 376             (! xdr_opaque_auth(xdrs, &(auth->ah_verf)))) {
 377                 perror("auth_none.c - Fatal marshalling problem");
 378         } else {
 379                 au->au_mpos = XDR_GETPOS(xdrs);
 380         }
 381         XDR_DESTROY(xdrs);
 382 }