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 <errno.h>
  32 #include "slist.h"
  33 #include "libnfs-zdr.h"
  34 #include "libnfs.h"
  35 #include "libnfs-raw.h"
  36 #include "libnfs-private.h"
  37
  38 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)
  39 {
  40         struct rpc_pdu *pdu;
  41         struct rpc_msg msg;
  42
  43         if (rpc == NULL) {
  44                 return NULL;
  45         }
  46
  47         pdu = malloc(sizeof(struct rpc_pdu));
  48         if (pdu == NULL) {
  49                 rpc_set_error(rpc, "Out of memory: Failed to allocate pdu structure");
  50                 return NULL;
  51         }
  52         memset(pdu, 0, sizeof(struct rpc_pdu));
  53         pdu->xid                = rpc->xid++;
  54         pdu->cb                 = cb;
  55         pdu->private_data       = private_data;
  56         pdu->zdr_decode_fn      = zdr_decode_fn;
  57         pdu->zdr_decode_bufsize = zdr_decode_bufsize;
  58
  59         zdrmem_create(&pdu->zdr, rpc->encodebuf, rpc->encodebuflen, ZDR_ENCODE);
  60         if (rpc->is_udp == 0) {
  61                 zdr_setpos(&pdu->zdr, 4); /* skip past the record marker */
  62         }
  63
  64         memset(&msg, 0, sizeof(struct rpc_msg));
  65         msg.rm_xid = pdu->xid;
  66         msg.rm_direction = CALL;
  67         msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
  68         msg.rm_call.cb_prog = program;
  69         msg.rm_call.cb_vers = version;
  70         msg.rm_call.cb_proc = procedure;
  71         msg.rm_call.cb_cred = rpc->auth->ah_cred;
  72         msg.rm_call.cb_verf = rpc->auth->ah_verf;
  73
  74         if (zdr_callmsg(&pdu->zdr, &msg) == 0) {
  75                 rpc_set_error(rpc, "zdr_callmsg failed");
  76                 zdr_destroy(&pdu->zdr);
  77                 free(pdu);
  78                 return NULL;
  79         }
  80
  81         return pdu;
  82 }
  83
  84 void rpc_free_pdu(struct rpc_context *rpc _U_, struct rpc_pdu *pdu)
  85 {
  86         if (pdu->outdata.data != NULL) {
  87                 free(pdu->outdata.data);
  88                 pdu->outdata.data = NULL;
  89         }
  90
  91         if (pdu->zdr_decode_buf != NULL) {
  92                 zdr_free(pdu->zdr_decode_fn, pdu->zdr_decode_buf);
  93                 free(pdu->zdr_decode_buf);
  94                 pdu->zdr_decode_buf = NULL;
  95         }
  96
  97         zdr_destroy(&pdu->zdr);
  98
  99         free(pdu);
 100 }
 101
 102
 103 int rpc_queue_pdu(struct rpc_context *rpc, struct rpc_pdu *pdu)
 104 {
 105         int size, recordmarker;
 106
 107         size = zdr_getpos(&pdu->zdr);
 108
 109         /* for udp we dont queue, we just send it straight away */
 110         if (rpc->is_udp != 0) {
 111 // XXX add a rpc->udp_dest_sock_size  and get rid of sys/socket.h and netinet/in.h
 112                 if (sendto(rpc->fd, rpc->encodebuf, size, MSG_DONTWAIT, rpc->udp_dest, sizeof(struct sockaddr_in)) < 0) {
 113                         rpc_set_error(rpc, "Sendto failed with errno %s", strerror(errno));
 114                         rpc_free_pdu(rpc, pdu);
 115                         return -1;
 116                 }
 117                 SLIST_ADD_END(&rpc->waitpdu, pdu);
 118                 return 0;
 119         }
 120
 121         /* write recordmarker */
 122         zdr_setpos(&pdu->zdr, 0);
 123         recordmarker = (size - 4) | 0x80000000;
 124         zdr_int(&pdu->zdr, &recordmarker);
 125
 126         pdu->outdata.size = size;
 127         pdu->outdata.data = malloc(pdu->outdata.size);
 128         if (pdu->outdata.data == NULL) {
 129                 rpc_set_error(rpc, "Out of memory. Failed to allocate buffer for pdu\n");
 130                 rpc_free_pdu(rpc, pdu);
 131                 return -1;
 132         }
 133
 134         memcpy(pdu->outdata.data, rpc->encodebuf, pdu->outdata.size);
 135         SLIST_ADD_END(&rpc->outqueue, pdu);
 136
 137         return 0;
 138 }
 139
 140 int rpc_get_pdu_size(char *buf)
 141 {
 142         uint32_t size;
 143
 144         size = ntohl(*(uint32_t *)buf);
 145
 146         return (size & 0x7fffffff) + 4;
 147 }
 148
 149 static int rpc_process_reply(struct rpc_context *rpc, struct rpc_pdu *pdu, ZDR *zdr)
 150 {
 151         struct rpc_msg msg;
 152
 153         memset(&msg, 0, sizeof(struct rpc_msg));
 154         msg.acpted_rply.ar_verf = _null_auth;
 155         if (pdu->zdr_decode_bufsize > 0) {
 156                 if (pdu->zdr_decode_buf != NULL) {
 157                         free(pdu->zdr_decode_buf);
 158                 }
 159                 pdu->zdr_decode_buf = malloc(pdu->zdr_decode_bufsize);
 160                 if (pdu->zdr_decode_buf == NULL) {
 161                         rpc_set_error(rpc, "zdr_replymsg failed in portmap_getport_reply");
 162                         pdu->cb(rpc, RPC_STATUS_ERROR, "Failed to allocate buffer for decoding of ZDR reply", pdu->private_data);
 163                         return 0;
 164                 }
 165                 memset(pdu->zdr_decode_buf, 0, pdu->zdr_decode_bufsize);
 166         }
 167         msg.acpted_rply.ar_results.where = pdu->zdr_decode_buf;
 168         msg.acpted_rply.ar_results.proc  = pdu->zdr_decode_fn;
 169
 170         if (zdr_replymsg(zdr, &msg) == 0) {
 171                 rpc_set_error(rpc, "zdr_replymsg failed in portmap_getport_reply");
 172                 pdu->cb(rpc, RPC_STATUS_ERROR, "Message rejected by server", pdu->private_data);
 173                 if (pdu->zdr_decode_buf != NULL) {
 174                         free(pdu->zdr_decode_buf);
 175                         pdu->zdr_decode_buf = NULL;
 176                 }
 177                 return 0;
 178         }
 179         if (msg.rm_reply.rp_stat != MSG_ACCEPTED) {
 180                 pdu->cb(rpc, RPC_STATUS_ERROR, "RPC Packet not accepted by the server", pdu->private_data);
 181                 return 0;
 182         }
 183         switch (msg.rm_reply.rp_acpt.ar_stat) {
 184         case SUCCESS:
 185                 pdu->cb(rpc, RPC_STATUS_SUCCESS, pdu->zdr_decode_buf, pdu->private_data);
 186                 break;
 187         case PROG_UNAVAIL:
 188                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Program not available", pdu->private_data);
 189                 break;
 190         case PROG_MISMATCH:
 191                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Program version mismatch", pdu->private_data);
 192                 break;
 193         case PROC_UNAVAIL:
 194                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Procedure not available", pdu->private_data);
 195                 break;
 196         case GARBAGE_ARGS:
 197                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Garbage arguments", pdu->private_data);
 198                 break;
 199         case SYSTEM_ERR:
 200                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: System Error", pdu->private_data);
 201                 break;
 202         default:
 203                 pdu->cb(rpc, RPC_STATUS_ERROR, "Unknown rpc response from server", pdu->private_data);
 204                 break;
 205         }
 206
 207         return 0;
 208 }
 209
 210 int rpc_process_pdu(struct rpc_context *rpc, char *buf, int size)
 211 {
 212         struct rpc_pdu *pdu;
 213         ZDR zdr;
 214         int pos, recordmarker = 0;
 215         unsigned int xid;
 216         char *reasbuf = NULL;
 217
 218         memset(&zdr, 0, sizeof(ZDR));
 219
 220         zdrmem_create(&zdr, buf, size, ZDR_DECODE);
 221         if (rpc->is_udp == 0) {
 222                 if (zdr_int(&zdr, &recordmarker) == 0) {
 223                         rpc_set_error(rpc, "zdr_int reading recordmarker failed");
 224                         zdr_destroy(&zdr);
 225                         return -1;
 226                 }
 227                 if (!(recordmarker&0x80000000)) {
 228                         zdr_destroy(&zdr);
 229                         if (rpc_add_fragment(rpc, buf+4, size-4) != 0) {
 230                                 rpc_set_error(rpc, "Failed to queue fragment for reassembly.");
 231                                 return -1;
 232                         }
 233                         return 0;
 234                 }
 235         }
 236
 237         /* reassembly */
 238         if (recordmarker != 0 && rpc->fragments != NULL) {
 239                 struct rpc_fragment *fragment;
 240                 uint64_t total = size - 4;
 241                 char *ptr;
 242
 243                 zdr_destroy(&zdr);
 244                 for (fragment = rpc->fragments; fragment; fragment = fragment->next) {
 245                         total += fragment->size;
 246                 }
 247
 248                 reasbuf = malloc(total);
 249                 if (reasbuf == NULL) {
 250                         rpc_set_error(rpc, "Failed to reassemble PDU");
 251                         rpc_free_all_fragments(rpc);
 252                         return -1;
 253                 }
 254                 ptr = reasbuf;
 255                 for (fragment = rpc->fragments; fragment; fragment = fragment->next) {
 256                         memcpy(ptr, fragment->data, fragment->size);
 257                         ptr += fragment->size;
 258                 }
 259                 memcpy(ptr, buf + 4, size - 4);
 260                 zdrmem_create(&zdr, reasbuf, total, ZDR_DECODE);
 261                 rpc_free_all_fragments(rpc);
 262         }
 263
 264         pos = zdr_getpos(&zdr);
 265         if (zdr_int(&zdr, (int *)&xid) == 0) {
 266                 rpc_set_error(rpc, "zdr_int reading xid failed");
 267                 zdr_destroy(&zdr);
 268                 if (reasbuf != NULL) {
 269                         free(reasbuf);
 270                 }
 271                 return -1;
 272         }
 273         zdr_setpos(&zdr, pos);
 274
 275         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 276                 if (pdu->xid != xid) {
 277                         continue;
 278                 }
 279                 if (rpc->is_udp == 0 || rpc->is_broadcast == 0) {
 280                         SLIST_REMOVE(&rpc->waitpdu, pdu);
 281                 }
 282                 if (rpc_process_reply(rpc, pdu, &zdr) != 0) {
 283                         rpc_set_error(rpc, "rpc_procdess_reply failed");
 284                 }
 285                 zdr_destroy(&zdr);
 286                 if (rpc->is_udp == 0 || rpc->is_broadcast == 0) {
 287                         rpc_free_pdu(rpc, pdu);
 288                 }
 289                 if (reasbuf != NULL) {
 290                         free(reasbuf);
 291                 }
 292                 return 0;
 293         }
 294         rpc_set_error(rpc, "No matching pdu found for xid:%d", xid);
 295         zdr_destroy(&zdr);
 296         if (reasbuf != NULL) {
 297                 free(reasbuf);
 298         }
 299         return -1;
 300 }
 301