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 int uid; 98 int gid; 99 int len; 100 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 int ngids; 189 long ngids_max; 190 char machname[MAXHOSTNAMELEN + 1]; 191 uid_t uid; 192 gid_t gid; 193 gid_t *gids; 194 195 ngids_max = sysconf(_SC_NGROUPS_MAX) + 1; 196 gids = malloc(sizeof(gid_t) * ngids_max); 197 if (gids == NULL) 198 return (NULL); 199 200 if (gethostname(machname, sizeof machname) == -1) 201 abort(); 202 machname[sizeof(machname) - 1] = 0; 203 uid = geteuid(); 204 gid = getegid(); 205 if ((ngids = getgroups(ngids_max, gids)) < 0) 206 abort(); 207 if (ngids > NGRPS) 208 ngids = NGRPS; 209 /* XXX: interface problem; those should all have been unsigned */ 210 return (authunix_create(machname, (int)uid, (int)gid, ngids, 211 (int *)gids)); 212 } 213 214 /* 215 * authunix operations 216 */ 217 218 /* ARGSUSED */ 219 static void 220 authunix_nextverf(auth) 221 AUTH *auth; 222 { 223 /* no action necessary */ 224 } 225 226 static bool_t 227 authunix_marshal(auth, xdrs) 228 AUTH *auth; 229 XDR *xdrs; 230 { 231 struct audata *au; 232 233 assert(auth != NULL); 234 assert(xdrs != NULL); 235 236 au = AUTH_PRIVATE(auth); 237 return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos)); 238 } 239 240 static bool_t 241 authunix_validate(auth, verf) 242 AUTH *auth; 243 struct opaque_auth *verf; 244 { 245 struct audata *au; 246 XDR xdrs; 247 248 assert(auth != NULL); 249 assert(verf != NULL); 250 251 if (verf->oa_flavor == AUTH_SHORT) { 252 au = AUTH_PRIVATE(auth); 253 xdrmem_create(&xdrs, verf->oa_base, verf->oa_length, 254 XDR_DECODE); 255 256 if (au->au_shcred.oa_base != NULL) { 257 mem_free(au->au_shcred.oa_base, 258 au->au_shcred.oa_length); 259 au->au_shcred.oa_base = NULL; 260 } 261 if (xdr_opaque_auth(&xdrs, &au->au_shcred)) { 262 auth->ah_cred = au->au_shcred; 263 } else { 264 xdrs.x_op = XDR_FREE; 265 (void)xdr_opaque_auth(&xdrs, &au->au_shcred); 266 au->au_shcred.oa_base = NULL; 267 auth->ah_cred = au->au_origcred; 268 } 269 marshal_new_auth(auth); 270 } 271 return (TRUE); 272 } 273 274 static bool_t 275 authunix_refresh(AUTH *auth, void *dummy) 276 { 277 struct audata *au = AUTH_PRIVATE(auth); 278 struct authunix_parms aup; 279 struct timeval now; 280 XDR xdrs; 281 int stat; 282 283 assert(auth != NULL); 284 285 if (auth->ah_cred.oa_base == au->au_origcred.oa_base) { 286 /* there is no hope. Punt */ 287 return (FALSE); 288 } 289 au->au_shfaults ++; 290 291 /* first deserialize the creds back into a struct authunix_parms */ 292 aup.aup_machname = NULL; 293 aup.aup_gids = NULL; 294 xdrmem_create(&xdrs, au->au_origcred.oa_base, 295 au->au_origcred.oa_length, XDR_DECODE); 296 stat = xdr_authunix_parms(&xdrs, &aup); 297 if (! stat) 298 goto done; 299 300 /* update the time and serialize in place */ 301 (void)gettimeofday(&now, NULL); 302 aup.aup_time = now.tv_sec; 303 xdrs.x_op = XDR_ENCODE; 304 XDR_SETPOS(&xdrs, 0); 305 stat = xdr_authunix_parms(&xdrs, &aup); 306 if (! stat) 307 goto done; 308 auth->ah_cred = au->au_origcred; 309 marshal_new_auth(auth); 310 done: 311 /* free the struct authunix_parms created by deserializing */ 312 xdrs.x_op = XDR_FREE; 313 (void)xdr_authunix_parms(&xdrs, &aup); 314 XDR_DESTROY(&xdrs); 315 return (stat); 316 } 317 318 static void 319 authunix_destroy(auth) 320 AUTH *auth; 321 { 322 struct audata *au; 323 324 assert(auth != NULL); 325 326 au = AUTH_PRIVATE(auth); 327 mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length); 328 329 if (au->au_shcred.oa_base != NULL) 330 mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length); 331 332 mem_free(auth->ah_private, sizeof(struct audata)); 333 334 if (auth->ah_verf.oa_base != NULL) 335 mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length); 336 337 mem_free(auth, sizeof(*auth)); 338 } 339 340 /* 341 * Marshals (pre-serializes) an auth struct. 342 * sets private data, au_marshed and au_mpos 343 */ 344 static void 345 marshal_new_auth(auth) 346 AUTH *auth; 347 { 348 XDR xdr_stream; 349 XDR *xdrs = &xdr_stream; 350 struct audata *au; 351 352 assert(auth != NULL); 353 354 au = AUTH_PRIVATE(auth); 355 xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE); 356 if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) || 357 (! xdr_opaque_auth(xdrs, &(auth->ah_verf)))) 358 warnx("auth_none.c - Fatal marshalling problem"); 359 else 360 au->au_mpos = XDR_GETPOS(xdrs); 361 XDR_DESTROY(xdrs); 362 } 363 364 static struct auth_ops * 365 authunix_ops() 366 { 367 static struct auth_ops ops; 368 369 /* VARIABLES PROTECTED BY ops_lock: ops */ 370 371 mutex_lock(&ops_lock); 372 if (ops.ah_nextverf == NULL) { 373 ops.ah_nextverf = authunix_nextverf; 374 ops.ah_marshal = authunix_marshal; 375 ops.ah_validate = authunix_validate; 376 ops.ah_refresh = authunix_refresh; 377 ops.ah_destroy = authunix_destroy; 378 } 379 mutex_unlock(&ops_lock); 380 return (&ops); 381 } 382