1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2000 by Cisco Systems, Inc. All rights reserved. 24 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 25 * Use is subject to license terms. 26 * Copyright 2014 Nexenta Systems, Inc. All rights reserved. 27 */ 28 29 /* 30 * iSCSI Software Initiator 31 */ 32 33 #include <sys/types.h> 34 #include <sys/errno.h> 35 #include <sys/conf.h> 36 #include <sys/cmn_err.h> 37 #include <sys/stat.h> 38 #include <sys/pathname.h> 39 #include <sys/door.h> 40 #include <sys/kmem.h> 41 #include <sys/socket.h> 42 #include <sys/fs/snode.h> 43 #include <netinet/in.h> 44 45 #include <sys/scsi/adapters/iscsi_door.h> 46 #include "iscsi.h" 47 48 #define ISCSI_DOOR_MAX_SEMA_VALUE 16 49 50 static boolean_t iscsi_door_init = B_FALSE; 51 static ksema_t iscsi_door_sema; 52 static krwlock_t iscsi_door_lock; 53 static door_handle_t iscsi_door_handle; 54 55 typedef struct _mybuffer { 56 size_t signature; 57 size_t size; 58 } mybuffer_t; 59 60 /* 61 * iscsi_door_ini 62 * 63 * This function initializes the variables needed to handle the door upcall. 64 */ 65 boolean_t 66 iscsi_door_ini(void) 67 { 68 ASSERT(!iscsi_door_init); 69 if (!iscsi_door_init) { 70 rw_init( 71 &iscsi_door_lock, 72 NULL, 73 RW_DRIVER, 74 NULL); 75 76 sema_init( 77 &iscsi_door_sema, 78 ISCSI_DOOR_MAX_SEMA_VALUE, 79 NULL, 80 SEMA_DRIVER, 81 NULL); 82 83 iscsi_door_handle = NULL; 84 iscsi_door_init = B_TRUE; 85 return (B_TRUE); 86 } 87 return (B_FALSE); 88 } 89 90 /* 91 * iscsi_door_term 92 * 93 * This function releases the resources allocated to handle the door 94 * upcall. It disconnects from the door if currently connected. 95 */ 96 boolean_t 97 iscsi_door_term(void) 98 { 99 ASSERT(iscsi_door_init); 100 if (iscsi_door_init) { 101 iscsi_door_init = B_FALSE; 102 iscsi_door_unbind(); 103 rw_destroy(&iscsi_door_lock); 104 sema_destroy(&iscsi_door_sema); 105 return (B_TRUE); 106 } 107 return (B_FALSE); 108 } 109 110 /* 111 * iscsi_door_bind 112 * 113 * This function tries to connect the iscsi_door. If it succeeds 114 * it keeps the vnode. 115 */ 116 boolean_t 117 iscsi_door_bind( 118 int did 119 ) 120 { 121 door_handle_t new_handle; 122 123 new_handle = door_ki_lookup(did); 124 if (new_handle == NULL) { 125 /* The lookup failed. */ 126 return (B_FALSE); 127 } 128 129 /* The new handle is stored. If we had one, it is released. */ 130 rw_enter(&iscsi_door_lock, RW_WRITER); 131 if (iscsi_door_handle != NULL) { 132 door_ki_rele(iscsi_door_handle); 133 } 134 iscsi_door_handle = new_handle; 135 rw_exit(&iscsi_door_lock); 136 137 return (B_TRUE); 138 } 139 140 /* 141 * iscsi_door_unbind 142 * 143 * This function releases the current door handle. 144 */ 145 void 146 iscsi_door_unbind(void) 147 { 148 rw_enter(&iscsi_door_lock, RW_WRITER); 149 if (iscsi_door_handle != NULL) { 150 door_ki_rele(iscsi_door_handle); 151 iscsi_door_handle = NULL; 152 } 153 rw_exit(&iscsi_door_lock); 154 } 155 156 /* 157 * iscsi_door_upcall 158 * 159 * This function tries to call the iscsi_door. 160 */ 161 static 162 boolean_t 163 iscsi_door_upcall(door_arg_t *arg) 164 { 165 int error; 166 167 /* 168 * This semaphore limits the number of simultaneous calls 169 * to the door. 170 */ 171 sema_p(&iscsi_door_sema); 172 /* 173 * The mutex protecting the iscsi_door_handle is entered. 174 */ 175 rw_enter(&iscsi_door_lock, RW_READER); 176 177 if (iscsi_door_handle == NULL) { 178 /* There's no door handle. */ 179 rw_exit(&iscsi_door_lock); 180 sema_v(&iscsi_door_sema); 181 return (B_FALSE); 182 } 183 error = door_ki_upcall(iscsi_door_handle, arg); 184 185 rw_exit(&iscsi_door_lock); 186 sema_v(&iscsi_door_sema); 187 188 if (error != 0) { 189 return (B_FALSE); 190 } else { 191 return (B_TRUE); 192 } 193 } 194 195 /* 196 * kfreehostent 197 * 198 * This function frees the memory returned by kgetipnodebyname. 199 */ 200 void 201 kfreehostent( 202 struct hostent *hptr 203 ) 204 { 205 mybuffer_t *buffer; 206 207 ASSERT(hptr != NULL); 208 if (hptr) { 209 buffer = (mybuffer_t *)((char *)hptr - sizeof (mybuffer_t)); 210 ASSERT(buffer->signature == ISCSI_DOOR_REQ_SIGNATURE); 211 if (buffer->signature == ISCSI_DOOR_REQ_SIGNATURE) { 212 kmem_free((void *)buffer, buffer->size); 213 return; 214 } 215 } 216 /* A message should be logged here. */ 217 } 218 219 /* 220 * kgetipnodebyname 221 * 222 * This function builds a request that will be sent to the iscsi_door. 223 * The iSCSI door after receiving the request calls getipnodebyaddr(). 224 * for more information on the input, output parameter and return value, 225 * consult the man page for getipnodebyname(). 226 * 227 * Before calling the iscsi door this function tries to do the conversion 228 * locally. If a name resolution is needed the iscsi door is called. 229 * 230 * There's some limitations to the information returned by this function. 231 * Only one address of the address list returned by getipnodebyname() is 232 * returned. The other parameters of the structure should be ignored. 233 */ 234 struct hostent * 235 kgetipnodebyname( 236 const char *name, 237 int af, 238 int flags, 239 int *error_num 240 ) 241 { 242 door_arg_t arg; 243 mybuffer_t *buffer; 244 size_t msg_size = ISCSI_DOOR_MAX_DATA_SIZE; 245 size_t hostent_size = ISCSI_DOOR_MAX_DATA_SIZE; 246 size_t buffer_size; 247 getipnodebyname_req_t *req; 248 getipnodebyname_cnf_t *cnf; 249 struct hostent *hptr; 250 251 252 buffer_size = msg_size + hostent_size + sizeof (mybuffer_t); 253 buffer = (mybuffer_t *)kmem_zalloc(buffer_size, KM_SLEEP); 254 255 if (buffer) { 256 257 /* 258 * The buffer was successfully allocated. 259 * 260 * Buffer 261 * 262 * +--------------------+ <--- buffer 263 * | mybuffer_t | 264 * +--------------------+ <--- hptr 265 * | | 266 * | | 267 * | hostent_size | 268 * | | 269 * | | 270 * | | 271 * +--------------------+ <--- req, cnf 272 * | | 273 * | | 274 * | | 275 * | msg_size | 276 * | | 277 * | | 278 * | | 279 * +--------------------+ 280 */ 281 buffer->signature = ISCSI_DOOR_REQ_SIGNATURE; 282 buffer->size = buffer_size; 283 284 hptr = (struct hostent *)((char *)buffer + sizeof (mybuffer_t)); 285 req = (getipnodebyname_req_t *)((char *)hptr + hostent_size); 286 cnf = (getipnodebyname_cnf_t *)((char *)hptr + hostent_size); 287 288 hostent_size -= sizeof (struct hostent); 289 290 /* 291 * We try first locally. If the conversion cannot be done 292 * by inet_pton the door is called. 293 * The cnf address is used as output buffer. 294 * inet_pton returns '1' if the conversion was successful. 295 */ 296 switch (af) { 297 case AF_INET: 298 hptr->h_length = sizeof (struct in_addr); 299 break; 300 case AF_INET6: 301 hptr->h_length = sizeof (struct in6_addr); 302 break; 303 default: 304 kfreehostent(hptr); 305 *error_num = NO_RECOVERY; 306 return (NULL); 307 } 308 if ((msg_size < hptr->h_length) || 309 (hostent_size < sizeof (char *))) { 310 kfreehostent(hptr); 311 *error_num = NO_RECOVERY; 312 return (NULL); 313 } 314 if (inet_pton(af, (char *)name, cnf) == 1) { 315 /* 316 * inet_pton converted the string successfully. 317 */ 318 hptr->h_addrtype = af; 319 hptr->h_addr_list = (char **)((char *)hptr + 320 sizeof (struct hostent)); 321 *hptr->h_addr_list = (char *)cnf; 322 return (hptr); 323 } 324 325 /* 326 * The name couldn't ne converted by inet_pton. The door is 327 * called. 328 */ 329 330 /* Header initialization. */ 331 req->hdr.signature = ISCSI_DOOR_REQ_SIGNATURE; 332 req->hdr.version = ISCSI_DOOR_REQ_VERSION_1; 333 req->hdr.opcode = ISCSI_DOOR_GETIPNODEBYNAME_REQ; 334 335 /* Body initialization. */ 336 req->name_length = strlen(name); 337 if (req->name_length > 338 (msg_size - sizeof (getipnodebyname_req_t) - 1)) { 339 kfreehostent(hptr); 340 *error_num = NO_RECOVERY; 341 return (NULL); 342 } 343 344 req->name_offset = sizeof (getipnodebyname_req_t); 345 req->af = af; 346 req->flags = flags; 347 bcopy( 348 name, 349 ((char *)req + req->name_offset), 350 req->name_length); 351 352 /* Door argument initialization. */ 353 arg.data_ptr = (char *)req; 354 arg.data_size = msg_size; 355 arg.desc_num = 0; 356 arg.desc_ptr = NULL; 357 arg.rbuf = (char *)cnf; 358 arg.rsize = msg_size; 359 360 if (iscsi_door_upcall(&arg) == B_FALSE) { 361 /* The door call failed */ 362 kfreehostent(hptr); 363 *error_num = NO_RECOVERY; 364 return (NULL); 365 } 366 367 /* 368 * The door call itself was successful. The value returned 369 * in arg.rbuf should be cnf, but we never know. 370 */ 371 cnf = (getipnodebyname_cnf_t *)arg.rbuf; 372 373 if ((cnf == NULL) || 374 (arg.rsize < sizeof (getipnodebyname_cnf_t)) || 375 (cnf->hdr.signature != ISCSI_DOOR_REQ_SIGNATURE) || 376 (cnf->hdr.version != ISCSI_DOOR_REQ_VERSION_1) || 377 (cnf->hdr.opcode != ISCSI_DOOR_GETIPNODEBYNAME_CNF) || 378 ((cnf->hdr.status != ISCSI_DOOR_STATUS_SUCCESS) && 379 (cnf->hdr.status != ISCSI_DOOR_STATUS_MORE))) { 380 /* The door didn't like the request */ 381 kfreehostent(hptr); 382 *error_num = NO_RECOVERY; 383 return (NULL); 384 } 385 386 if (cnf->h_addr_list_length == 0) { 387 kfreehostent(hptr); 388 *error_num = HOST_NOT_FOUND; 389 return (NULL); 390 } 391 392 hptr->h_addrtype = cnf->h_addrtype; 393 hptr->h_length = cnf->h_addrlen; 394 hptr->h_addr_list = (char **)((char *)hptr + 395 sizeof (struct hostent)); 396 *hptr->h_addr_list = ((char *)cnf + cnf->h_addr_list_offset); 397 return (hptr); 398 } else { 399 *error_num = NO_RECOVERY; 400 return (NULL); 401 } 402 } 403