1 /* $NetBSD: auth_unix.c,v 1.23 2012/03/20 17:14:50 matt 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 #include <sys/cdefs.h> 33 #if defined(LIBC_SCCS) && !defined(lint) 34 #if 0 35 static char *sccsid = "@(#)auth_unix.c 1.19 87/08/11 Copyr 1984 Sun Micro"; 36 static char *sccsid = "@(#)auth_unix.c 2.2 88/08/01 4.0 RPCSRC"; 37 #else 38 __RCSID("$NetBSD: auth_unix.c,v 1.23 2012/03/20 17:14:50 matt Exp $"); 39 #endif 40 #endif 41 42 /* 43 * auth_unix.c, Implements UNIX style authentication parameters. 44 * 45 * Copyright (C) 1984, Sun Microsystems, Inc. 46 * 47 * The system is very weak. The client uses no encryption for it's 48 * credentials and only sends null verifiers. The server sends backs 49 * null verifiers or optionally a verifier that suggests a new short hand 50 * for the credentials. 51 * 52 */ 53 54 #include "namespace.h" 55 #include "reentrant.h" 56 #include <sys/param.h> 57 58 #include <assert.h> 59 #include <err.h> 60 #include <stdio.h> 61 #include <stdlib.h> 62 #include <string.h> 63 #include <unistd.h> 64 65 #include <rpc/types.h> 66 #include <rpc/xdr.h> 67 #include <rpc/auth.h> 68 #include <rpc/auth_unix.h> 69 70 #ifdef __weak_alias 71 __weak_alias(authunix_create,_authunix_create) 72 __weak_alias(authunix_create_default,_authunix_create_default) 73 #endif 74 75 76 /* auth_unix.c */ 77 static void authunix_nextverf(AUTH *); 78 static bool_t authunix_marshal(AUTH *, XDR *); 79 static bool_t authunix_validate(AUTH *, struct opaque_auth *); 80 static bool_t authunix_refresh(AUTH *); 81 static void authunix_destroy(AUTH *); 82 static void marshal_new_auth(AUTH *); 83 static const struct auth_ops *authunix_ops(void); 84 85 /* 86 * This struct is pointed to by the ah_private field of an auth_handle. 87 */ 88 struct audata { 89 struct opaque_auth au_origcred; /* original credentials */ 90 struct opaque_auth au_shcred; /* short hand cred */ 91 u_long au_shfaults; /* short hand cache faults */ 92 char au_marshed[MAX_AUTH_BYTES]; 93 u_int au_mpos; /* xdr pos at end of marshed */ 94 }; 95 #define AUTH_PRIVATE(auth) ((struct audata *)auth->ah_private) 96 97 /* 98 * Create a unix style authenticator. 99 * Returns an auth handle with the given stuff in it. 100 */ 101 AUTH * 102 authunix_create(char *machname, int uid, int gid, int len, int *aup_gids) 103 { 104 struct authunix_parms aup; 105 char mymem[MAX_AUTH_BYTES]; 106 struct timeval now; 107 XDR xdrs; 108 AUTH *auth; 109 struct audata *au; 110 111 /* 112 * Allocate and set up auth handle 113 */ 114 au = NULL; 115 auth = mem_alloc(sizeof(*auth)); 116 #ifndef KERNEL 117 if (auth == NULL) { 118 warnx("authunix_create: out of memory"); 119 goto cleanup_authunix_create; 120 } 121 #endif 122 au = mem_alloc(sizeof(*au)); 123 #ifndef KERNEL 124 if (au == NULL) { 125 warnx("authunix_create: out of memory"); 126 goto cleanup_authunix_create; 127 } 128 #endif 129 auth->ah_ops = authunix_ops(); 130 auth->ah_private = au; 131 auth->ah_verf = au->au_shcred = _null_auth; 132 au->au_shfaults = 0; 133 au->au_origcred.oa_base = NULL; 134 135 /* 136 * fill in param struct from the given params 137 */ 138 (void)gettimeofday(&now, NULL); 139 aup.aup_time = (u_long)now.tv_sec; /* XXX: truncate on 32 bit */ 140 aup.aup_machname = machname; 141 aup.aup_uid = uid; 142 aup.aup_gid = gid; 143 aup.aup_len = (u_int)len; 144 aup.aup_gids = aup_gids; 145 146 /* 147 * Serialize the parameters into origcred 148 */ 149 xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE); 150 if (! xdr_authunix_parms(&xdrs, &aup)) 151 abort(); 152 au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs); 153 au->au_origcred.oa_flavor = AUTH_UNIX; 154 #ifdef KERNEL 155 au->au_origcred.oa_base = mem_alloc((size_t)len); 156 #else 157 if ((au->au_origcred.oa_base = mem_alloc((size_t)len)) == NULL) { 158 warnx("authunix_create: out of memory"); 159 goto cleanup_authunix_create; 160 } 161 #endif 162 memmove(au->au_origcred.oa_base, mymem, (size_t)len); 163 164 /* 165 * set auth handle to reflect new cred. 166 */ 167 auth->ah_cred = au->au_origcred; 168 marshal_new_auth(auth); 169 return (auth); 170 #ifndef KERNEL 171 cleanup_authunix_create: 172 if (auth) 173 mem_free(auth, sizeof(*auth)); 174 if (au) { 175 if (au->au_origcred.oa_base) 176 mem_free(au->au_origcred.oa_base, (u_int)len); 177 mem_free(au, sizeof(*au)); 178 } 179 return (NULL); 180 #endif 181 } 182 183 /* 184 * Returns an auth handle with parameters determined by doing lots of 185 * syscalls. 186 */ 187 AUTH * 188 authunix_create_default(void) 189 { 190 int len; 191 char machname[MAXHOSTNAMELEN + 1]; 192 uid_t uid; 193 gid_t gid; 194 gid_t gids[NGRPS]; 195 196 if (gethostname(machname, sizeof machname) == -1) 197 abort(); 198 machname[sizeof(machname) - 1] = 0; 199 uid = geteuid(); 200 gid = getegid(); 201 if ((len = getgroups(NGRPS, gids)) < 0) 202 abort(); 203 /* XXX: interface problem; those should all have been unsigned */ 204 return (authunix_create(machname, (int)uid, (int)gid, len, 205 (int *)gids)); 206 } 207 208 /* 209 * authunix operations 210 */ 211 212 /* ARGSUSED */ 213 static void 214 authunix_nextverf(AUTH *auth) 215 { 216 /* no action necessary */ 217 } 218 219 static bool_t 220 authunix_marshal(AUTH *auth, XDR *xdrs) 221 { 222 struct audata *au; 223 224 _DIAGASSERT(auth != NULL); 225 _DIAGASSERT(xdrs != NULL); 226 227 au = AUTH_PRIVATE(auth); 228 return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos)); 229 } 230 231 static bool_t 232 authunix_validate(AUTH *auth, struct opaque_auth *verf) 233 { 234 struct audata *au; 235 XDR xdrs; 236 237 _DIAGASSERT(auth != NULL); 238 _DIAGASSERT(verf != NULL); 239 240 if (verf->oa_flavor == AUTH_SHORT) { 241 au = AUTH_PRIVATE(auth); 242 xdrmem_create(&xdrs, verf->oa_base, verf->oa_length, 243 XDR_DECODE); 244 245 if (au->au_shcred.oa_base != NULL) { 246 mem_free(au->au_shcred.oa_base, 247 au->au_shcred.oa_length); 248 au->au_shcred.oa_base = NULL; 249 } 250 if (xdr_opaque_auth(&xdrs, &au->au_shcred)) { 251 auth->ah_cred = au->au_shcred; 252 } else { 253 xdrs.x_op = XDR_FREE; 254 (void)xdr_opaque_auth(&xdrs, &au->au_shcred); 255 au->au_shcred.oa_base = NULL; 256 auth->ah_cred = au->au_origcred; 257 } 258 marshal_new_auth(auth); 259 } 260 return (TRUE); 261 } 262 263 static bool_t 264 authunix_refresh(AUTH *auth) 265 { 266 struct audata *au = AUTH_PRIVATE(auth); 267 struct authunix_parms aup; 268 struct timeval now; 269 XDR xdrs; 270 int stat; 271 272 _DIAGASSERT(auth != NULL); 273 274 if (auth->ah_cred.oa_base == au->au_origcred.oa_base) { 275 /* there is no hope. Punt */ 276 return (FALSE); 277 } 278 au->au_shfaults++; 279 280 /* first deserialize the creds back into a struct authunix_parms */ 281 aup.aup_machname = NULL; 282 aup.aup_gids = NULL; 283 xdrmem_create(&xdrs, au->au_origcred.oa_base, 284 au->au_origcred.oa_length, XDR_DECODE); 285 stat = xdr_authunix_parms(&xdrs, &aup); 286 if (! stat) 287 goto done; 288 289 /* update the time and serialize in place */ 290 (void)gettimeofday(&now, NULL); 291 aup.aup_time = (u_long)now.tv_sec; /* XXX: truncate on 32 bit */ 292 xdrs.x_op = XDR_ENCODE; 293 XDR_SETPOS(&xdrs, 0); 294 stat = xdr_authunix_parms(&xdrs, &aup); 295 if (! stat) 296 goto done; 297 auth->ah_cred = au->au_origcred; 298 marshal_new_auth(auth); 299 done: 300 /* free the struct authunix_parms created by deserializing */ 301 xdrs.x_op = XDR_FREE; 302 (void)xdr_authunix_parms(&xdrs, &aup); 303 XDR_DESTROY(&xdrs); 304 return (stat); 305 } 306 307 static void 308 authunix_destroy(AUTH *auth) 309 { 310 struct audata *au; 311 312 _DIAGASSERT(auth != NULL); 313 314 au = AUTH_PRIVATE(auth); 315 mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length); 316 317 if (au->au_shcred.oa_base != NULL) 318 mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length); 319 320 mem_free(auth->ah_private, sizeof(struct audata)); 321 322 if (auth->ah_verf.oa_base != NULL) 323 mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length); 324 325 mem_free(auth, sizeof(*auth)); 326 } 327 328 /* 329 * Marshals (pre-serializes) an auth struct. 330 * sets private data, au_marshed and au_mpos 331 */ 332 static void 333 marshal_new_auth(AUTH *auth) 334 { 335 XDR xdr_stream; 336 XDR *xdrs = &xdr_stream; 337 struct audata *au; 338 339 _DIAGASSERT(auth != NULL); 340 341 au = AUTH_PRIVATE(auth); 342 xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE); 343 if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) || 344 (! xdr_opaque_auth(xdrs, &(auth->ah_verf)))) 345 warnx("auth_none.c - Fatal marshalling problem"); 346 else 347 au->au_mpos = XDR_GETPOS(xdrs); 348 XDR_DESTROY(xdrs); 349 } 350 351 static const struct auth_ops * 352 authunix_ops(void) 353 { 354 static struct auth_ops ops; 355 #ifdef _REENTRANT 356 extern mutex_t ops_lock; 357 #endif 358 359 /* VARIABLES PROTECTED BY ops_lock: ops */ 360 361 mutex_lock(&ops_lock); 362 if (ops.ah_nextverf == NULL) { 363 ops.ah_nextverf = authunix_nextverf; 364 ops.ah_marshal = authunix_marshal; 365 ops.ah_validate = authunix_validate; 366 ops.ah_refresh = authunix_refresh; 367 ops.ah_destroy = authunix_destroy; 368 } 369 mutex_unlock(&ops_lock); 370 return (&ops); 371 } 372