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 <stdio.h>
  47
  48 #include <rpc/types.h>
  49 #include <rpc/xdr.h>
  50 #include <rpc/auth.h>
  51 #include <rpc/auth_unix.h>
  52
  53 /*
  54  * Unix authenticator operations vector
  55  */
  56 static void     authunix_nextverf();
  57 static bool_t   authunix_marshal();
  58 static bool_t   authunix_validate();
  59 static bool_t   authunix_refresh();
  60 static void     authunix_destroy();
  61
  62 static struct auth_ops auth_unix_ops = {
  63         authunix_nextverf,
  64         authunix_marshal,
  65         authunix_validate,
  66         authunix_refresh,
  67         authunix_destroy
  68 };
  69
  70 /*
  71  * This struct is pointed to by the ah_private field of an auth_handle.
  72  */
  73 struct audata {
  74         struct opaque_auth      au_origcred;    /* original credentials */
  75         struct opaque_auth      au_shcred;      /* short hand cred */
  76         u_long                  au_shfaults;    /* short hand cache faults */
  77         char                    au_marshed[MAX_AUTH_BYTES];
  78         u_int                   au_mpos;        /* xdr pos at end of marshed */
  79 };
  80 #define AUTH_PRIVATE(auth)      ((struct audata *)auth->ah_private)
  81
  82 static bool_t marshal_new_auth();
  83
  84
  85 /*
  86  * Create a unix style authenticator.
  87  * Returns an auth handle with the given stuff in it.
  88  */
  89 AUTH *
  90 authunix_create(machname, uid, gid, len, aup_gids)
  91         char *machname;
  92         int uid;
  93         int gid;
  94         register int len;
  95         int *aup_gids;
  96 {
  97         struct authunix_parms aup;
  98         char mymem[MAX_AUTH_BYTES];
  99         struct timeval now;
 100         XDR xdrs;
 101         register AUTH *auth;
 102         register struct audata *au;
 103
 104         /*
 105          * Allocate and set up auth handle
 106          */
 107         auth = (AUTH *)mem_alloc(sizeof(*auth));
 108 #ifndef KERNEL
 109         if (auth == NULL) {
 110                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 111                 return (NULL);
 112         }
 113 #endif
 114         au = (struct audata *)mem_alloc(sizeof(*au));
 115 #ifndef KERNEL
 116         if (au == NULL) {
 117                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 118                 return (NULL);
 119         }
 120 #endif
 121         auth->ah_ops = &auth_unix_ops;
 122         auth->ah_private = (caddr_t)au;
 123         auth->ah_verf = au->au_shcred = _null_auth;
 124         au->au_shfaults = 0;
 125
 126         /*
 127          * fill in param struct from the given params
 128          */
 129         (void)gettimeofday(&now,  (struct timezone *)0);
 130         aup.aup_time = now.tv_sec;
 131         aup.aup_machname = machname;
 132         aup.aup_uid = uid;
 133         aup.aup_gid = gid;
 134         aup.aup_len = (u_int)len;
 135         aup.aup_gids = aup_gids;
 136
 137         /*
 138          * Serialize the parameters into origcred
 139          */
 140         xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE);
 141         if (! xdr_authunix_parms(&xdrs, &aup))
 142                 abort();
 143         au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs);
 144         au->au_origcred.oa_flavor = AUTH_UNIX;
 145 #ifdef KERNEL
 146         au->au_origcred.oa_base = mem_alloc((u_int) len);
 147 #else
 148         if ((au->au_origcred.oa_base = mem_alloc((u_int) len)) == NULL) {
 149                 (void)fprintf(stderr, "authunix_create: out of memory\n");
 150                 return (NULL);
 151         }
 152 #endif
 153         bcopy(mymem, au->au_origcred.oa_base, (u_int)len);
 154
 155         /*
 156          * set auth handle to reflect new cred.
 157          */
 158         auth->ah_cred = au->au_origcred;
 159         marshal_new_auth(auth);
 160         return (auth);
 161 }
 162
 163 /*
 164  * Returns an auth handle with parameters determined by doing lots of
 165  * syscalls.
 166  */
 167 AUTH *
 168 authunix_create_default()
 169 {
 170         register int len;
 171         char machname[MAX_MACHINE_NAME + 1];
 172         register int uid;
 173         register int gid;
 174         int gids[NGRPS];
 175
 176         if (gethostname(machname, MAX_MACHINE_NAME) == -1)
 177                 abort();
 178         machname[MAX_MACHINE_NAME] = 0;
 179         uid = geteuid();
 180         gid = getegid();
 181         if ((len = getgroups(NGRPS, gids)) < 0)
 182                 abort();
 183         return (authunix_create(machname, uid, gid, len, gids));
 184 }
 185
 186 /*
 187  * authunix operations
 188  */
 189
 190 static void
 191 authunix_nextverf(auth)
 192         AUTH *auth;
 193 {
 194         /* no action necessary */
 195 }
 196
 197 static bool_t
 198 authunix_marshal(auth, xdrs)
 199         AUTH *auth;
 200         XDR *xdrs;
 201 {
 202         register struct audata *au = AUTH_PRIVATE(auth);
 203
 204         return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos));
 205 }
 206
 207 static bool_t
 208 authunix_validate(auth, verf)
 209         register AUTH *auth;
 210         struct opaque_auth verf;
 211 {
 212         register struct audata *au;
 213         XDR xdrs;
 214
 215         if (verf.oa_flavor == AUTH_SHORT) {
 216                 au = AUTH_PRIVATE(auth);
 217                 xdrmem_create(&xdrs, verf.oa_base, verf.oa_length, XDR_DECODE);
 218
 219                 if (au->au_shcred.oa_base != NULL) {
 220                         mem_free(au->au_shcred.oa_base,
 221                             au->au_shcred.oa_length);
 222                         au->au_shcred.oa_base = NULL;
 223                 }
 224                 if (xdr_opaque_auth(&xdrs, &au->au_shcred)) {
 225                         auth->ah_cred = au->au_shcred;
 226                 } else {
 227                         xdrs.x_op = XDR_FREE;
 228                         (void)xdr_opaque_auth(&xdrs, &au->au_shcred);
 229                         au->au_shcred.oa_base = NULL;
 230                         auth->ah_cred = au->au_origcred;
 231                 }
 232                 marshal_new_auth(auth);
 233         }
 234         return (TRUE);
 235 }
 236
 237 static bool_t
 238 authunix_refresh(auth)
 239         register AUTH *auth;
 240 {
 241         register struct audata *au = AUTH_PRIVATE(auth);
 242         struct authunix_parms aup;
 243         struct timeval now;
 244         XDR xdrs;
 245         register int stat;
 246
 247         if (auth->ah_cred.oa_base == au->au_origcred.oa_base) {
 248                 /* there is no hope.  Punt */
 249                 return (FALSE);
 250         }
 251         au->au_shfaults ++;
 252
 253         /* first deserialize the creds back into a struct authunix_parms */
 254         aup.aup_machname = NULL;
 255         aup.aup_gids = (int *)NULL;
 256         xdrmem_create(&xdrs, au->au_origcred.oa_base,
 257             au->au_origcred.oa_length, XDR_DECODE);
 258         stat = xdr_authunix_parms(&xdrs, &aup);
 259         if (! stat)
 260                 goto done;
 261
 262         /* update the time and serialize in place */
 263         (void)gettimeofday(&now, (struct timezone *)0);
 264         aup.aup_time = now.tv_sec;
 265         xdrs.x_op = XDR_ENCODE;
 266         XDR_SETPOS(&xdrs, 0);
 267         stat = xdr_authunix_parms(&xdrs, &aup);
 268         if (! stat)
 269                 goto done;
 270         auth->ah_cred = au->au_origcred;
 271         marshal_new_auth(auth);
 272 done:
 273         /* free the struct authunix_parms created by deserializing */
 274         xdrs.x_op = XDR_FREE;
 275         (void)xdr_authunix_parms(&xdrs, &aup);
 276         XDR_DESTROY(&xdrs);
 277         return (stat);
 278 }
 279
 280 static void
 281 authunix_destroy(auth)
 282         register AUTH *auth;
 283 {
 284         register struct audata *au = AUTH_PRIVATE(auth);
 285
 286         mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length);
 287
 288         if (au->au_shcred.oa_base != NULL)
 289                 mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length);
 290
 291         mem_free(auth->ah_private, sizeof(struct audata));
 292
 293         if (auth->ah_verf.oa_base != NULL)
 294                 mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length);
 295
 296         mem_free((caddr_t)auth, sizeof(*auth));
 297 }
 298
 299 /*
 300  * Marshals (pre-serializes) an auth struct.
 301  * sets private data, au_marshed and au_mpos
 302  */
 303 static bool_t
 304 marshal_new_auth(auth)
 305         register AUTH *auth;
 306 {
 307         XDR             xdr_stream;
 308         register XDR    *xdrs = &xdr_stream;
 309         register struct audata *au = AUTH_PRIVATE(auth);
 310
 311         xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE);
 312         if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) ||
 313             (! xdr_opaque_auth(xdrs, &(auth->ah_verf)))) {
 314                 perror("auth_none.c - Fatal marshalling problem");
 315         } else {
 316                 au->au_mpos = XDR_GETPOS(xdrs);
 317         }
 318         XDR_DESTROY(xdrs);
 319 }