lib/pdu.c

   1 /*
   2    Copyright (C) 2010 by Ronnie Sahlberg <ronniesahlberg@gmail.com>
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as published by
   6    the Free Software Foundation; either version 2.1 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program; if not, see <http://www.gnu.org/licenses/>.
  16 */
  17 #ifdef HAVE_CONFIG_H
  18 #include "config.h"
  19 #endif
  20
  21 #ifdef AROS
  22 #include "aros_compat.h"
  23 #endif
  24
  25 #ifdef WIN32
  26 #include "win32_compat.h"
  27 #endif
  28
  29 #ifdef HAVE_NETINET_IN_H
  30 #include <netinet/in.h>
  31 #endif
  32
  33 #ifdef HAVE_SYS_SOCKET_H
  34 #include <sys/socket.h>
  35 #endif
  36
  37 #ifdef HAVE_STRINGS_H
  38 #include <strings.h>
  39 #endif
  40
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <string.h>
  44 #include <assert.h>
  45 #include <errno.h>
  46 #include "slist.h"
  47 #include "libnfs-zdr.h"
  48 #include "libnfs.h"
  49 #include "libnfs-raw.h"
  50 #include "libnfs-private.h"
  51
  52 void rpc_reset_queue(struct rpc_queue *q)
  53 {
  54         q->head = NULL;
  55         q->tail = NULL;
  56 }
  57
  58 /*
  59  * Push to the tail end of the queue
  60  */
  61 void rpc_enqueue(struct rpc_queue *q, struct rpc_pdu *pdu)
  62 {
  63         if (q->head == NULL)
  64                 q->head = pdu;
  65         else
  66                 q->tail->next = pdu;
  67         q->tail = pdu;
  68 }
  69
  70 /*
  71  * Push to the front/head of the queue
  72  */
  73 void rpc_return_to_queue(struct rpc_queue *q, struct rpc_pdu *pdu)
  74 {
  75         pdu->next = q->head;
  76         q->head = pdu;
  77         if (q->tail == NULL)
  78                 q->tail = pdu;
  79 }
  80
  81 struct rpc_pdu *rpc_allocate_pdu(struct rpc_context *rpc, int program, int version, int procedure, rpc_cb cb, void *private_data, zdrproc_t zdr_decode_fn, int zdr_decode_bufsize)
  82 {
  83         struct rpc_pdu *pdu;
  84         struct rpc_msg msg;
  85
  86         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  87
  88         pdu = malloc(sizeof(struct rpc_pdu));
  89         if (pdu == NULL) {
  90                 rpc_set_error(rpc, "Out of memory: Failed to allocate pdu structure");
  91                 return NULL;
  92         }
  93         memset(pdu, 0, sizeof(struct rpc_pdu));
  94         pdu->xid                = rpc->xid++;
  95         pdu->cb                 = cb;
  96         pdu->private_data       = private_data;
  97         pdu->zdr_decode_fn      = zdr_decode_fn;
  98         pdu->zdr_decode_bufsize = zdr_decode_bufsize;
  99
 100         zdrmem_create(&pdu->zdr, rpc->encodebuf, rpc->encodebuflen, ZDR_ENCODE);
 101         if (rpc->is_udp == 0) {
 102                 zdr_setpos(&pdu->zdr, 4); /* skip past the record marker */
 103         }
 104
 105         memset(&msg, 0, sizeof(struct rpc_msg));
 106         msg.xid                = pdu->xid;
 107         msg.direction          = CALL;
 108         msg.body.cbody.rpcvers = RPC_MSG_VERSION;
 109         msg.body.cbody.prog    = program;
 110         msg.body.cbody.vers    = version;
 111         msg.body.cbody.proc    = procedure;
 112         msg.body.cbody.cred    = rpc->auth->ah_cred;
 113         msg.body.cbody.verf    = rpc->auth->ah_verf;
 114
 115         if (zdr_callmsg(rpc, &pdu->zdr, &msg) == 0) {
 116                 rpc_set_error(rpc, "zdr_callmsg failed with %s",
 117                               rpc_get_error(rpc));
 118                 zdr_destroy(&pdu->zdr);
 119                 free(pdu);
 120                 return NULL;
 121         }
 122
 123         return pdu;
 124 }
 125
 126 void rpc_free_pdu(struct rpc_context *rpc, struct rpc_pdu *pdu)
 127 {
 128         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 129
 130         if (pdu->outdata.data != NULL) {
 131                 free(pdu->outdata.data);
 132                 pdu->outdata.data = NULL;
 133         }
 134
 135         if (pdu->zdr_decode_buf != NULL) {
 136                 zdr_free(pdu->zdr_decode_fn, pdu->zdr_decode_buf);
 137                 free(pdu->zdr_decode_buf);
 138                 pdu->zdr_decode_buf = NULL;
 139         }
 140
 141         zdr_destroy(&pdu->zdr);
 142
 143         free(pdu);
 144 }
 145
 146 void rpc_set_next_xid(struct rpc_context *rpc, uint32_t xid)
 147 {
 148         rpc->xid = xid;
 149 }
 150
 151 int rpc_queue_pdu(struct rpc_context *rpc, struct rpc_pdu *pdu)
 152 {
 153         int size, recordmarker;
 154
 155         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 156
 157         size = zdr_getpos(&pdu->zdr);
 158
 159         /* for udp we dont queue, we just send it straight away */
 160         if (rpc->is_udp != 0) {
 161 // XXX add a rpc->udp_dest_sock_size  and get rid of sys/socket.h and netinet/in.h
 162                 if (sendto(rpc->fd, rpc->encodebuf, size, MSG_DONTWAIT, rpc->udp_dest, sizeof(struct sockaddr_in)) < 0) {
 163                         rpc_set_error(rpc, "Sendto failed with errno %s", strerror(errno));
 164                         rpc_free_pdu(rpc, pdu);
 165                         return -1;
 166                 }
 167                 rpc_enqueue(&rpc->waitpdu, pdu);
 168                 return 0;
 169         }
 170
 171         /* write recordmarker */
 172         zdr_setpos(&pdu->zdr, 0);
 173         recordmarker = (size - 4) | 0x80000000;
 174         zdr_int(&pdu->zdr, &recordmarker);
 175
 176         pdu->outdata.size = size;
 177         pdu->outdata.data = malloc(pdu->outdata.size);
 178         if (pdu->outdata.data == NULL) {
 179                 rpc_set_error(rpc, "Out of memory. Failed to allocate buffer for pdu\n");
 180                 rpc_free_pdu(rpc, pdu);
 181                 return -1;
 182         }
 183
 184         memcpy(pdu->outdata.data, rpc->encodebuf, pdu->outdata.size);
 185         rpc_enqueue(&rpc->outqueue, pdu);
 186
 187         return 0;
 188 }
 189
 190 int rpc_get_pdu_size(char *buf)
 191 {
 192         uint32_t size;
 193
 194         size = ntohl(*(uint32_t *)buf);
 195
 196         return (size & 0x7fffffff) + 4;
 197 }
 198
 199 static int rpc_process_reply(struct rpc_context *rpc, struct rpc_pdu *pdu, ZDR *zdr)
 200 {
 201         struct rpc_msg msg;
 202
 203         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 204
 205         memset(&msg, 0, sizeof(struct rpc_msg));
 206         msg.body.rbody.reply.areply.verf = _null_auth;
 207         if (pdu->zdr_decode_bufsize > 0) {
 208                 if (pdu->zdr_decode_buf != NULL) {
 209                         free(pdu->zdr_decode_buf);
 210                 }
 211                 pdu->zdr_decode_buf = malloc(pdu->zdr_decode_bufsize);
 212                 if (pdu->zdr_decode_buf == NULL) {
 213                         rpc_set_error(rpc, "Failed to allocate memory for "
 214                                       "zdr_encode_buf in rpc_process_reply");
 215                         pdu->cb(rpc, RPC_STATUS_ERROR, "Failed to allocate "
 216                                 "buffer for decoding of ZDR reply",
 217                                 pdu->private_data);
 218                         return 0;
 219                 }
 220                 memset(pdu->zdr_decode_buf, 0, pdu->zdr_decode_bufsize);
 221         }
 222         msg.body.rbody.reply.areply.reply_data.results.where = pdu->zdr_decode_buf;
 223         msg.body.rbody.reply.areply.reply_data.results.proc  = pdu->zdr_decode_fn;
 224
 225         if (zdr_replymsg(rpc, zdr, &msg) == 0) {
 226                 rpc_set_error(rpc, "zdr_replymsg failed in rpc_process_reply: "
 227                               "%s", rpc_get_error(rpc));
 228                 pdu->cb(rpc, RPC_STATUS_ERROR, "Message rejected by server",
 229                         pdu->private_data);
 230                 if (pdu->zdr_decode_buf != NULL) {
 231                         free(pdu->zdr_decode_buf);
 232                         pdu->zdr_decode_buf = NULL;
 233                 }
 234                 return 0;
 235         }
 236         if (msg.body.rbody.stat != MSG_ACCEPTED) {
 237                 pdu->cb(rpc, RPC_STATUS_ERROR, "RPC Packet not accepted by the server", pdu->private_data);
 238                 return 0;
 239         }
 240         switch (msg.body.rbody.reply.areply.stat) {
 241         case SUCCESS:
 242                 pdu->cb(rpc, RPC_STATUS_SUCCESS, pdu->zdr_decode_buf, pdu->private_data);
 243                 break;
 244         case PROG_UNAVAIL:
 245                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Program not available", pdu->private_data);
 246                 break;
 247         case PROG_MISMATCH:
 248                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Program version mismatch", pdu->private_data);
 249                 break;
 250         case PROC_UNAVAIL:
 251                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Procedure not available", pdu->private_data);
 252                 break;
 253         case GARBAGE_ARGS:
 254                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Garbage arguments", pdu->private_data);
 255                 break;
 256         case SYSTEM_ERR:
 257                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: System Error", pdu->private_data);
 258                 break;
 259         default:
 260                 pdu->cb(rpc, RPC_STATUS_ERROR, "Unknown rpc response from server", pdu->private_data);
 261                 break;
 262         }
 263
 264         return 0;
 265 }
 266
 267 int rpc_process_pdu(struct rpc_context *rpc, char *buf, int size)
 268 {
 269         struct rpc_pdu *pdu, *prev_pdu;
 270         ZDR zdr;
 271         int pos, recordmarker = 0;
 272         uint32_t xid;
 273         char *reasbuf = NULL;
 274
 275         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 276
 277         memset(&zdr, 0, sizeof(ZDR));
 278
 279         zdrmem_create(&zdr, buf, size, ZDR_DECODE);
 280         if (rpc->is_udp == 0) {
 281                 if (zdr_int(&zdr, &recordmarker) == 0) {
 282                         rpc_set_error(rpc, "zdr_int reading recordmarker failed");
 283                         zdr_destroy(&zdr);
 284                         return -1;
 285                 }
 286                 if (!(recordmarker&0x80000000)) {
 287                         zdr_destroy(&zdr);
 288                         if (rpc_add_fragment(rpc, buf+4, size-4) != 0) {
 289                                 rpc_set_error(rpc, "Failed to queue fragment for reassembly.");
 290                                 return -1;
 291                         }
 292                         return 0;
 293                 }
 294         }
 295
 296         /* reassembly */
 297         if (recordmarker != 0 && rpc->fragments != NULL) {
 298                 struct rpc_fragment *fragment;
 299                 uint32_t total = size - 4;
 300                 char *ptr;
 301
 302                 zdr_destroy(&zdr);
 303                 for (fragment = rpc->fragments; fragment; fragment = fragment->next) {
 304                         total += fragment->size;
 305                 }
 306
 307                 reasbuf = malloc(total);
 308                 if (reasbuf == NULL) {
 309                         rpc_set_error(rpc, "Failed to reassemble PDU");
 310                         rpc_free_all_fragments(rpc);
 311                         return -1;
 312                 }
 313                 ptr = reasbuf;
 314                 for (fragment = rpc->fragments; fragment; fragment = fragment->next) {
 315                         memcpy(ptr, fragment->data, fragment->size);
 316                         ptr += fragment->size;
 317                 }
 318                 memcpy(ptr, buf + 4, size - 4);
 319                 zdrmem_create(&zdr, reasbuf, total, ZDR_DECODE);
 320                 rpc_free_all_fragments(rpc);
 321         }
 322
 323         pos = zdr_getpos(&zdr);
 324         if (zdr_int(&zdr, (int *)&xid) == 0) {
 325                 rpc_set_error(rpc, "zdr_int reading xid failed");
 326                 zdr_destroy(&zdr);
 327                 if (reasbuf != NULL) {
 328                         free(reasbuf);
 329                 }
 330                 return -1;
 331         }
 332         zdr_setpos(&zdr, pos);
 333
 334         /* Linear traverse singly-linked list, but track previous
 335          * entry for optimised removal */
 336         prev_pdu = NULL;
 337         for (pdu=rpc->waitpdu.head; pdu; pdu=pdu->next) {
 338                 if (pdu->xid != xid) {
 339                         prev_pdu = pdu;
 340                         continue;
 341                 }
 342                 if (rpc->is_udp == 0 || rpc->is_broadcast == 0) {
 343                         /* Singly-linked but we track head and tail */
 344                         if (pdu == rpc->waitpdu.head)
 345                                 rpc->waitpdu.head = pdu->next;
 346                         if (pdu == rpc->waitpdu.tail)
 347                                 rpc->waitpdu.tail = prev_pdu;
 348                         if (prev_pdu != NULL)
 349                                 prev_pdu->next = pdu->next;
 350                 }
 351                 if (rpc_process_reply(rpc, pdu, &zdr) != 0) {
 352                         rpc_set_error(rpc, "rpc_procdess_reply failed");
 353                 }
 354                 zdr_destroy(&zdr);
 355                 if (rpc->is_udp == 0 || rpc->is_broadcast == 0) {
 356                         rpc_free_pdu(rpc, pdu);
 357                 }
 358                 if (reasbuf != NULL) {
 359                         free(reasbuf);
 360                 }
 361                 return 0;
 362         }
 363         rpc_set_error(rpc, "No matching pdu found for xid:%d", xid);
 364         zdr_destroy(&zdr);
 365         if (reasbuf != NULL) {
 366                 free(reasbuf);
 367         }
 368         return -1;
 369 }
 370