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 WIN32
  18 #include "win32_compat.h"
  19 #ifndef MSG_DONTWAIT
  20 #define MSG_DONTWAIT 0
  21 #endif
  22 #else
  23 #include <strings.h>
  24 #endif/*WIN32*/
  25
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <sys/socket.h>
  30 #include <netinet/in.h>
  31 #include <assert.h>
  32 #include <errno.h>
  33 #include "slist.h"
  34 #include "libnfs-zdr.h"
  35 #include "libnfs.h"
  36 #include "libnfs-raw.h"
  37 #include "libnfs-private.h"
  38
  39 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)
  40 {
  41         struct rpc_pdu *pdu;
  42         struct rpc_msg msg;
  43
  44         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  45
  46         pdu = malloc(sizeof(struct rpc_pdu));
  47         if (pdu == NULL) {
  48                 rpc_set_error(rpc, "Out of memory: Failed to allocate pdu structure");
  49                 return NULL;
  50         }
  51         memset(pdu, 0, sizeof(struct rpc_pdu));
  52         pdu->xid                = rpc->xid++;
  53         pdu->cb                 = cb;
  54         pdu->private_data       = private_data;
  55         pdu->zdr_decode_fn      = zdr_decode_fn;
  56         pdu->zdr_decode_bufsize = zdr_decode_bufsize;
  57
  58         zdrmem_create(&pdu->zdr, rpc->encodebuf, rpc->encodebuflen, ZDR_ENCODE);
  59         if (rpc->is_udp == 0) {
  60                 zdr_setpos(&pdu->zdr, 4); /* skip past the record marker */
  61         }
  62
  63         memset(&msg, 0, sizeof(struct rpc_msg));
  64         msg.xid                = pdu->xid;
  65         msg.direction          = CALL;
  66         msg.body.cbody.rpcvers = RPC_MSG_VERSION;
  67         msg.body.cbody.prog    = program;
  68         msg.body.cbody.vers    = version;
  69         msg.body.cbody.proc    = procedure;
  70         msg.body.cbody.cred    = rpc->auth->ah_cred;
  71         msg.body.cbody.verf    = rpc->auth->ah_verf;
  72
  73         if (zdr_callmsg(&pdu->zdr, &msg) == 0) {
  74                 rpc_set_error(rpc, "zdr_callmsg failed");
  75                 zdr_destroy(&pdu->zdr);
  76                 free(pdu);
  77                 return NULL;
  78         }
  79
  80         return pdu;
  81 }
  82
  83 void rpc_free_pdu(struct rpc_context *rpc, struct rpc_pdu *pdu)
  84 {
  85         assert(rpc->magic == RPC_CONTEXT_MAGIC);
  86
  87         if (pdu->outdata.data != NULL) {
  88                 free(pdu->outdata.data);
  89                 pdu->outdata.data = NULL;
  90         }
  91
  92         if (pdu->zdr_decode_buf != NULL) {
  93                 zdr_free(pdu->zdr_decode_fn, pdu->zdr_decode_buf);
  94                 free(pdu->zdr_decode_buf);
  95                 pdu->zdr_decode_buf = NULL;
  96         }
  97
  98         zdr_destroy(&pdu->zdr);
  99
 100         free(pdu);
 101 }
 102
 103
 104 int rpc_queue_pdu(struct rpc_context *rpc, struct rpc_pdu *pdu)
 105 {
 106         int size, recordmarker;
 107
 108         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 109
 110         size = zdr_getpos(&pdu->zdr);
 111
 112         /* for udp we dont queue, we just send it straight away */
 113         if (rpc->is_udp != 0) {
 114 // XXX add a rpc->udp_dest_sock_size  and get rid of sys/socket.h and netinet/in.h
 115                 if (sendto(rpc->fd, rpc->encodebuf, size, MSG_DONTWAIT, rpc->udp_dest, sizeof(struct sockaddr_in)) < 0) {
 116                         rpc_set_error(rpc, "Sendto failed with errno %s", strerror(errno));
 117                         rpc_free_pdu(rpc, pdu);
 118                         return -1;
 119                 }
 120                 SLIST_ADD_END(&rpc->waitpdu, pdu);
 121                 return 0;
 122         }
 123
 124         /* write recordmarker */
 125         zdr_setpos(&pdu->zdr, 0);
 126         recordmarker = (size - 4) | 0x80000000;
 127         zdr_int(&pdu->zdr, &recordmarker);
 128
 129         pdu->outdata.size = size;
 130         pdu->outdata.data = malloc(pdu->outdata.size);
 131         if (pdu->outdata.data == NULL) {
 132                 rpc_set_error(rpc, "Out of memory. Failed to allocate buffer for pdu\n");
 133                 rpc_free_pdu(rpc, pdu);
 134                 return -1;
 135         }
 136
 137         memcpy(pdu->outdata.data, rpc->encodebuf, pdu->outdata.size);
 138         SLIST_ADD_END(&rpc->outqueue, pdu);
 139
 140         return 0;
 141 }
 142
 143 int rpc_get_pdu_size(char *buf)
 144 {
 145         uint32_t size;
 146
 147         size = ntohl(*(uint32_t *)buf);
 148
 149         return (size & 0x7fffffff) + 4;
 150 }
 151
 152 static int rpc_process_reply(struct rpc_context *rpc, struct rpc_pdu *pdu, ZDR *zdr)
 153 {
 154         struct rpc_msg msg;
 155
 156         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 157
 158         memset(&msg, 0, sizeof(struct rpc_msg));
 159         msg.body.rbody.reply.areply.verf = _null_auth;
 160         if (pdu->zdr_decode_bufsize > 0) {
 161                 if (pdu->zdr_decode_buf != NULL) {
 162                         free(pdu->zdr_decode_buf);
 163                 }
 164                 pdu->zdr_decode_buf = malloc(pdu->zdr_decode_bufsize);
 165                 if (pdu->zdr_decode_buf == NULL) {
 166                         rpc_set_error(rpc, "zdr_replymsg failed in portmap_getport_reply");
 167                         pdu->cb(rpc, RPC_STATUS_ERROR, "Failed to allocate buffer for decoding of ZDR reply", pdu->private_data);
 168                         return 0;
 169                 }
 170                 memset(pdu->zdr_decode_buf, 0, pdu->zdr_decode_bufsize);
 171         }
 172         msg.body.rbody.reply.areply.reply_data.results.where = pdu->zdr_decode_buf;
 173         msg.body.rbody.reply.areply.reply_data.results.proc  = pdu->zdr_decode_fn;
 174
 175         if (zdr_replymsg(zdr, &msg) == 0) {
 176                 rpc_set_error(rpc, "zdr_replymsg failed in portmap_getport_reply");
 177                 pdu->cb(rpc, RPC_STATUS_ERROR, "Message rejected by server", pdu->private_data);
 178                 if (pdu->zdr_decode_buf != NULL) {
 179                         free(pdu->zdr_decode_buf);
 180                         pdu->zdr_decode_buf = NULL;
 181                 }
 182                 return 0;
 183         }
 184         if (msg.body.rbody.stat != MSG_ACCEPTED) {
 185                 pdu->cb(rpc, RPC_STATUS_ERROR, "RPC Packet not accepted by the server", pdu->private_data);
 186                 return 0;
 187         }
 188         switch (msg.body.rbody.reply.areply.stat) {
 189         case SUCCESS:
 190                 pdu->cb(rpc, RPC_STATUS_SUCCESS, pdu->zdr_decode_buf, pdu->private_data);
 191                 break;
 192         case PROG_UNAVAIL:
 193                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Program not available", pdu->private_data);
 194                 break;
 195         case PROG_MISMATCH:
 196                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Program version mismatch", pdu->private_data);
 197                 break;
 198         case PROC_UNAVAIL:
 199                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Procedure not available", pdu->private_data);
 200                 break;
 201         case GARBAGE_ARGS:
 202                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Garbage arguments", pdu->private_data);
 203                 break;
 204         case SYSTEM_ERR:
 205                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: System Error", pdu->private_data);
 206                 break;
 207         default:
 208                 pdu->cb(rpc, RPC_STATUS_ERROR, "Unknown rpc response from server", pdu->private_data);
 209                 break;
 210         }
 211
 212         return 0;
 213 }
 214
 215 int rpc_process_pdu(struct rpc_context *rpc, char *buf, int size)
 216 {
 217         struct rpc_pdu *pdu;
 218         ZDR zdr;
 219         int pos, recordmarker = 0;
 220         unsigned int xid;
 221         char *reasbuf = NULL;
 222
 223         assert(rpc->magic == RPC_CONTEXT_MAGIC);
 224
 225         memset(&zdr, 0, sizeof(ZDR));
 226
 227         zdrmem_create(&zdr, buf, size, ZDR_DECODE);
 228         if (rpc->is_udp == 0) {
 229                 if (zdr_int(&zdr, &recordmarker) == 0) {
 230                         rpc_set_error(rpc, "zdr_int reading recordmarker failed");
 231                         zdr_destroy(&zdr);
 232                         return -1;
 233                 }
 234                 if (!(recordmarker&0x80000000)) {
 235                         zdr_destroy(&zdr);
 236                         if (rpc_add_fragment(rpc, buf+4, size-4) != 0) {
 237                                 rpc_set_error(rpc, "Failed to queue fragment for reassembly.");
 238                                 return -1;
 239                         }
 240                         return 0;
 241                 }
 242         }
 243
 244         /* reassembly */
 245         if (recordmarker != 0 && rpc->fragments != NULL) {
 246                 struct rpc_fragment *fragment;
 247                 uint32_t total = size - 4;
 248                 char *ptr;
 249
 250                 zdr_destroy(&zdr);
 251                 for (fragment = rpc->fragments; fragment; fragment = fragment->next) {
 252                         total += fragment->size;
 253                 }
 254
 255                 reasbuf = malloc(total);
 256                 if (reasbuf == NULL) {
 257                         rpc_set_error(rpc, "Failed to reassemble PDU");
 258                         rpc_free_all_fragments(rpc);
 259                         return -1;
 260                 }
 261                 ptr = reasbuf;
 262                 for (fragment = rpc->fragments; fragment; fragment = fragment->next) {
 263                         memcpy(ptr, fragment->data, fragment->size);
 264                         ptr += fragment->size;
 265                 }
 266                 memcpy(ptr, buf + 4, size - 4);
 267                 zdrmem_create(&zdr, reasbuf, total, ZDR_DECODE);
 268                 rpc_free_all_fragments(rpc);
 269         }
 270
 271         pos = zdr_getpos(&zdr);
 272         if (zdr_int(&zdr, (int *)&xid) == 0) {
 273                 rpc_set_error(rpc, "zdr_int reading xid failed");
 274                 zdr_destroy(&zdr);
 275                 if (reasbuf != NULL) {
 276                         free(reasbuf);
 277                 }
 278                 return -1;
 279         }
 280         zdr_setpos(&zdr, pos);
 281
 282         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 283                 if (pdu->xid != xid) {
 284                         continue;
 285                 }
 286                 if (rpc->is_udp == 0 || rpc->is_broadcast == 0) {
 287                         SLIST_REMOVE(&rpc->waitpdu, pdu);
 288                 }
 289                 if (rpc_process_reply(rpc, pdu, &zdr) != 0) {
 290                         rpc_set_error(rpc, "rpc_procdess_reply failed");
 291                 }
 292                 zdr_destroy(&zdr);
 293                 if (rpc->is_udp == 0 || rpc->is_broadcast == 0) {
 294                         rpc_free_pdu(rpc, pdu);
 295                 }
 296                 if (reasbuf != NULL) {
 297                         free(reasbuf);
 298                 }
 299                 return 0;
 300         }
 301         rpc_set_error(rpc, "No matching pdu found for xid:%d", xid);
 302         zdr_destroy(&zdr);
 303         if (reasbuf != NULL) {
 304                 free(reasbuf);
 305         }
 306         return -1;
 307 }
 308