sunrpc/auth_unix.c

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