1 /* $NetBSD: auth_unix.c,v 1.18 2000/07/06 03:03:30 christos Exp $ */ 2 3 /* 4 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for 5 * unrestricted use provided that this legend is included on all tape 6 * media and as a part of the software program in whole or part. Users 7 * may copy or modify Sun RPC without charge, but are not authorized 8 * to license or distribute it to anyone else except as part of a product or 9 * program developed by the user. 10 * 11 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE 12 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR 13 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE. 14 * 15 * Sun RPC is provided with no support and without any obligation on the 16 * part of Sun Microsystems, Inc. to assist in its use, correction, 17 * modification or enhancement. 18 * 19 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE 20 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC 21 * OR ANY PART THEREOF. 22 * 23 * In no event will Sun Microsystems, Inc. be liable for any lost revenue 24 * or profits or other special, indirect and consequential damages, even if 25 * Sun has been advised of the possibility of such damages. 26 * 27 * Sun Microsystems, Inc. 28 * 2550 Garcia Avenue 29 * Mountain View, California 94043 30 */ 31 32 #if defined(LIBC_SCCS) && !defined(lint) 33 static char *sccsid2 = "@(#)auth_unix.c 1.19 87/08/11 Copyr 1984 Sun Micro"; 34 static char *sccsid = "@(#)auth_unix.c 2.2 88/08/01 4.0 RPCSRC"; 35 #endif 36 #include <sys/cdefs.h> 37 __FBSDID("$FreeBSD$"); 38 39 /* 40 * auth_unix.c, Implements UNIX style authentication parameters. 41 * 42 * Copyright (C) 1984, Sun Microsystems, Inc. 43 * 44 * The system is very weak. The client uses no encryption for it's 45 * credentials and only sends null verifiers. The server sends backs 46 * null verifiers or optionally a verifier that suggests a new short hand 47 * for the credentials. 48 * 49 */ 50 51 #include "namespace.h" 52 #include "reentrant.h" 53 #include <sys/param.h> 54 55 #include <assert.h> 56 #include <err.h> 57 #include <stdio.h> 58 #include <stdlib.h> 59 #include <unistd.h> 60 #include <string.h> 61 62 #include <rpc/types.h> 63 #include <rpc/xdr.h> 64 #include <rpc/auth.h> 65 #include <rpc/auth_unix.h> 66 #include "un-namespace.h" 67 #include "mt_misc.h" 68 69 /* auth_unix.c */ 70 static void authunix_nextverf (AUTH *); 71 static bool_t authunix_marshal (AUTH *, XDR *); 72 static bool_t authunix_validate (AUTH *, struct opaque_auth *); 73 static bool_t authunix_refresh (AUTH *, void *); 74 static void authunix_destroy (AUTH *); 75 static void marshal_new_auth (AUTH *); 76 static struct auth_ops *authunix_ops (void); 77 78 /* 79 * This struct is pointed to by the ah_private field of an auth_handle. 80 */ 81 struct audata { 82 struct opaque_auth au_origcred; /* original credentials */ 83 struct opaque_auth au_shcred; /* short hand cred */ 84 u_long au_shfaults; /* short hand cache faults */ 85 char au_marshed[MAX_AUTH_BYTES]; 86 u_int au_mpos; /* xdr pos at end of marshed */ 87 }; 88 #define AUTH_PRIVATE(auth) ((struct audata *)auth->ah_private) 89 90 /* 91 * Create a unix style authenticator. 92 * Returns an auth handle with the given stuff in it. 93 */ 94 AUTH * 95 authunix_create(machname, uid, gid, len, aup_gids) 96 char *machname; 97 u_int uid; 98 u_int gid; 99 int len; 100 u_int *aup_gids; 101 { 102 struct authunix_parms aup; 103 char mymem[MAX_AUTH_BYTES]; 104 struct timeval now; 105 XDR xdrs; 106 AUTH *auth; 107 struct audata *au; 108 109 /* 110 * Allocate and set up auth handle 111 */ 112 au = NULL; 113 auth = mem_alloc(sizeof(*auth)); 114 #ifndef _KERNEL 115 if (auth == NULL) { 116 warnx("authunix_create: out of memory"); 117 goto cleanup_authunix_create; 118 } 119 #endif 120 au = mem_alloc(sizeof(*au)); 121 #ifndef _KERNEL 122 if (au == NULL) { 123 warnx("authunix_create: out of memory"); 124 goto cleanup_authunix_create; 125 } 126 #endif 127 auth->ah_ops = authunix_ops(); 128 auth->ah_private = (caddr_t)au; 129 auth->ah_verf = au->au_shcred = _null_auth; 130 au->au_shfaults = 0; 131 au->au_origcred.oa_base = NULL; 132 133 /* 134 * fill in param struct from the given params 135 */ 136 (void)gettimeofday(&now, NULL); 137 aup.aup_time = now.tv_sec; 138 aup.aup_machname = machname; 139 aup.aup_uid = uid; 140 aup.aup_gid = gid; 141 aup.aup_len = (u_int)len; 142 aup.aup_gids = aup_gids; 143 144 /* 145 * Serialize the parameters into origcred 146 */ 147 xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE); 148 if (! xdr_authunix_parms(&xdrs, &aup)) 149 abort(); 150 au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs); 151 au->au_origcred.oa_flavor = AUTH_UNIX; 152 #ifdef _KERNEL 153 au->au_origcred.oa_base = mem_alloc((u_int) len); 154 #else 155 if ((au->au_origcred.oa_base = mem_alloc((u_int) len)) == NULL) { 156 warnx("authunix_create: out of memory"); 157 goto cleanup_authunix_create; 158 } 159 #endif 160 memmove(au->au_origcred.oa_base, mymem, (size_t)len); 161 162 /* 163 * set auth handle to reflect new cred. 164 */ 165 auth->ah_cred = au->au_origcred; 166 marshal_new_auth(auth); 167 return (auth); 168 #ifndef _KERNEL 169 cleanup_authunix_create: 170 if (auth) 171 mem_free(auth, sizeof(*auth)); 172 if (au) { 173 if (au->au_origcred.oa_base) 174 mem_free(au->au_origcred.oa_base, (u_int)len); 175 mem_free(au, sizeof(*au)); 176 } 177 return (NULL); 178 #endif 179 } 180 181 /* 182 * Returns an auth handle with parameters determined by doing lots of 183 * syscalls. 184 */ 185 AUTH * 186 authunix_create_default() 187 { 188 AUTH *auth; 189 int ngids; 190 long ngids_max; 191 char machname[MAXHOSTNAMELEN + 1]; 192 uid_t uid; 193 gid_t gid; 194 gid_t *gids; 195 196 ngids_max = sysconf(_SC_NGROUPS_MAX) + 1; 197 gids = malloc(sizeof(gid_t) * ngids_max); 198 if (gids == NULL) 199 return (NULL); 200 201 if (gethostname(machname, sizeof machname) == -1) 202 abort(); 203 machname[sizeof(machname) - 1] = 0; 204 uid = geteuid(); 205 gid = getegid(); 206 if ((ngids = getgroups(ngids_max, gids)) < 0) 207 abort(); 208 if (ngids > NGRPS) 209 ngids = NGRPS; 210 /* XXX: interface problem; we should translate from uid_t and gid_t */ 211 auth = authunix_create(machname, uid, gid, ngids, gids); 212 free(gids); 213 return (auth); 214 } 215 216 /* 217 * authunix operations 218 */ 219 220 /* ARGSUSED */ 221 static void 222 authunix_nextverf(auth) 223 AUTH *auth; 224 { 225 /* no action necessary */ 226 } 227 228 static bool_t 229 authunix_marshal(auth, xdrs) 230 AUTH *auth; 231 XDR *xdrs; 232 { 233 struct audata *au; 234 235 assert(auth != NULL); 236 assert(xdrs != NULL); 237 238 au = AUTH_PRIVATE(auth); 239 return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos)); 240 } 241 242 static bool_t 243 authunix_validate(auth, verf) 244 AUTH *auth; 245 struct opaque_auth *verf; 246 { 247 struct audata *au; 248 XDR xdrs; 249 250 assert(auth != NULL); 251 assert(verf != NULL); 252 253 if (verf->oa_flavor == AUTH_SHORT) { 254 au = AUTH_PRIVATE(auth); 255 xdrmem_create(&xdrs, verf->oa_base, verf->oa_length, 256 XDR_DECODE); 257 258 if (au->au_shcred.oa_base != NULL) { 259 mem_free(au->au_shcred.oa_base, 260 au->au_shcred.oa_length); 261 au->au_shcred.oa_base = NULL; 262 } 263 if (xdr_opaque_auth(&xdrs, &au->au_shcred)) { 264 auth->ah_cred = au->au_shcred; 265 } else { 266 xdrs.x_op = XDR_FREE; 267 (void)xdr_opaque_auth(&xdrs, &au->au_shcred); 268 au->au_shcred.oa_base = NULL; 269 auth->ah_cred = au->au_origcred; 270 } 271 marshal_new_auth(auth); 272 } 273 return (TRUE); 274 } 275 276 static bool_t 277 authunix_refresh(AUTH *auth, void *dummy) 278 { 279 struct audata *au = AUTH_PRIVATE(auth); 280 struct authunix_parms aup; 281 struct timeval now; 282 XDR xdrs; 283 int stat; 284 285 assert(auth != NULL); 286 287 if (auth->ah_cred.oa_base == au->au_origcred.oa_base) { 288 /* there is no hope. Punt */ 289 return (FALSE); 290 } 291 au->au_shfaults ++; 292 293 /* first deserialize the creds back into a struct authunix_parms */ 294 aup.aup_machname = NULL; 295 aup.aup_gids = NULL; 296 xdrmem_create(&xdrs, au->au_origcred.oa_base, 297 au->au_origcred.oa_length, XDR_DECODE); 298 stat = xdr_authunix_parms(&xdrs, &aup); 299 if (! stat) 300 goto done; 301 302 /* update the time and serialize in place */ 303 (void)gettimeofday(&now, NULL); 304 aup.aup_time = now.tv_sec; 305 xdrs.x_op = XDR_ENCODE; 306 XDR_SETPOS(&xdrs, 0); 307 stat = xdr_authunix_parms(&xdrs, &aup); 308 if (! stat) 309 goto done; 310 auth->ah_cred = au->au_origcred; 311 marshal_new_auth(auth); 312 done: 313 /* free the struct authunix_parms created by deserializing */ 314 xdrs.x_op = XDR_FREE; 315 (void)xdr_authunix_parms(&xdrs, &aup); 316 XDR_DESTROY(&xdrs); 317 return (stat); 318 } 319 320 static void 321 authunix_destroy(auth) 322 AUTH *auth; 323 { 324 struct audata *au; 325 326 assert(auth != NULL); 327 328 au = AUTH_PRIVATE(auth); 329 mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length); 330 331 if (au->au_shcred.oa_base != NULL) 332 mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length); 333 334 mem_free(auth->ah_private, sizeof(struct audata)); 335 336 if (auth->ah_verf.oa_base != NULL) 337 mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length); 338 339 mem_free(auth, sizeof(*auth)); 340 } 341 342 /* 343 * Marshals (pre-serializes) an auth struct. 344 * sets private data, au_marshed and au_mpos 345 */ 346 static void 347 marshal_new_auth(auth) 348 AUTH *auth; 349 { 350 XDR xdr_stream; 351 XDR *xdrs = &xdr_stream; 352 struct audata *au; 353 354 assert(auth != NULL); 355 356 au = AUTH_PRIVATE(auth); 357 xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE); 358 if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) || 359 (! xdr_opaque_auth(xdrs, &(auth->ah_verf)))) 360 warnx("auth_none.c - Fatal marshalling problem"); 361 else 362 au->au_mpos = XDR_GETPOS(xdrs); 363 XDR_DESTROY(xdrs); 364 } 365 366 static struct auth_ops * 367 authunix_ops() 368 { 369 static struct auth_ops ops; 370 371 /* VARIABLES PROTECTED BY ops_lock: ops */ 372 373 mutex_lock(&ops_lock); 374 if (ops.ah_nextverf == NULL) { 375 ops.ah_nextverf = authunix_nextverf; 376 ops.ah_marshal = authunix_marshal; 377 ops.ah_validate = authunix_validate; 378 ops.ah_refresh = authunix_refresh; 379 ops.ah_destroy = authunix_destroy; 380 } 381 mutex_unlock(&ops_lock); 382 return (&ops); 383 } 384